@article {pmid40131314, year = {2025}, author = {Biyashev, B and Zhusanbayeva, A and Kirkimbayeva, Z and Zholdasbekova, A and Sarybayeva, D}, title = {Surveillance of Salmonella and antimicrobial resistance in industrial poultry enterprises: biofilm-forming strains and critical control points.}, journal = {Journal of medical microbiology}, volume = {74}, number = {3}, pages = {}, doi = {10.1099/jmm.0.001993}, pmid = {40131314}, issn = {1473-5644}, mesh = {Animals ; *Biofilms/drug effects/growth & development ; *Salmonella/drug effects/isolation & purification/physiology ; *Poultry/microbiology ; *Anti-Bacterial Agents/pharmacology ; *Salmonella Infections, Animal/microbiology/epidemiology/prevention & control ; *Poultry Diseases/microbiology/epidemiology ; *Drug Resistance, Bacterial ; Farms ; Microbial Sensitivity Tests ; Prevalence ; Chickens/microbiology ; Animal Husbandry/methods ; }, abstract = {Introduction. Salmonella contamination in the poultry industry poses substantial health risks, especially due to biofilm-forming strains that resist disinfection and antibiotic treatment. Biofilm-forming Salmonella strains are particularly challenging to control, as they adhere to surfaces in production environments, leading to persistent contamination. This study assesses the prevalence of Salmonella, examines antibiotic resistance patterns and evaluates biosecurity effectiveness at poultry farms in Kazakhstan.Hypothesis/Gap Statement. There is limited data on the prevalence and antibiotic resistance of biofilm-forming Salmonella strains in Kazakhstan's poultry industry, highlighting a need to characterize these strains to inform effective control measures.Aim. The purpose of this study was to systematically identify and characterize Salmonella strains, including biofilm-forming types, within industrial poultry enterprises in Kazakhstan.Methodology. A total of 660 samples were collected from various poultry production sites, including feed, water sources, cloacal flushes and shoe covers. Salmonella detection followed standardized protocols, and antibiotic sensitivity of identified strains was analysed to evaluate resistance patterns.Results. Salmonella was detected in 11.5% (95% CI) of the 660 samples, with the highest contamination observed in shoe covers, cloacal flushes, feed and water. This prevalence rate indicates a significant presence of the pathogen in the country's poultry production chain, falling between the higher rates seen in countries like China (22.2%) and Egypt (29.1%) and the lower rates observed in countries like Brazil (3.4%). The most prevalent strain was Salmonella gallinarum-pullorum (61.8%), followed by Salmonella typhimurium (18.4%) and Salmonella enteritidis (14.5%). Antibiotic sensitivity analysis revealed that S. gallinarum-pullorum was largely susceptible to common antibiotics, while S. typhimurium displayed considerable resistance, emphasizing the need for alternative treatments.Conclusion. The findings underscore the importance of strict sanitary and hygiene standards throughout poultry production, with a particular focus on managing biofilm-forming Salmonella strains. Implementing comprehensive Hazard Analysis and Critical Control Points protocols is essential to address contamination hotspots effectively. Future studies should investigate genetic mechanisms underlying biofilm formation and resistance in Salmonella strains to inform targeted interventions, ultimately improving food safety and public health outcomes.}, }
@article {pmid40130849, year = {2025}, author = {Varin-Simon, J and Haney, EF and Colin, M and Velard, F and Gangloff, SC and Hancock, REW and Reffuveille, F}, title = {D-enantiomeric antibiofilm peptides effective against anaerobic Cutibacterium acnes biofilm.}, journal = {Microbiology spectrum}, volume = {}, number = {}, pages = {e0252324}, doi = {10.1128/spectrum.02523-24}, pmid = {40130849}, issn = {2165-0497}, abstract = {The emergence of antibiotic resistance, biofilm formation, and internalization by host cells contribute to a high risk of chronic infections, highlighting the necessity to develop novel therapeutic strategies. Identification of natural host defense peptides (HDPs) with promising antimicrobial and antibiofilm activities led to the development of synthetic peptides with broad-spectrum efficacy. However, few studies have examined their effect on anaerobic bacterial species. This study aimed to test the effect of synthetic HDPs on Cutibacterium acnes, an anaerobe species involved in 10% of prosthesis joint infections (PJI). A preliminary screen identified three peptides (DJK5, AB009-D, and AB101-D) with promising activity against four C. acnes strains (two of which were isolated from PJI). A bactericidal effect was observed for the three peptides with 50% of planktonic bacteria killing for AB009-D and AB101-D after only 3 hours of contact. DJK5 and AB009-D inhibited the C. acnes adhesion on plastic and titanium supports with a 2-log decrease in bacterial cells. In the presence of peptides, the morphology of C. acnes cells was altered with an increase in cell length observed, especially for one of the non-PJI-related strains. Against mature biofilms, AB101-D was the most effective with an approximate 2-log decrease in adhered CFUs, indicating the induction of bacterial dispersion or death. DJK5 also inhibited C. acnes internalization by osteoblasts, with a reduction of the internalized bacteria quantity for three strains. Overall, this study demonstrates that synthetic HDPs are effective against anaerobic bacteria and hold promise as novel therapeutic candidates to prevent or treat C. acnes PJIs.IMPORTANCEThe emergence of antibiotic tolerance highlights the necessity to develop novel therapeutic strategies with promising antimicrobial but also antibiofilm activities. In this study, we tested the effect of synthetic host defense peptides (HDPs) on Cutibacterium acnes, an anaerobic species, rarely studied, whereas involved in 10% of prosthesis joint infections (PJI). In our study, we demonstrate that the selected synthetic HDPs are effective against this anaerobic bacteria, both as a preventive treatment (effect on planktonic growth, bacterial adhesion, and biofilm formation) and against internalization of C. acnes by osteoblasts, revealing that these peptides are promising as novel therapeutic candidates to prevent or treat C. acnes PJIs.}, }
@article {pmid40130064, year = {2025}, author = {Horng, YT and Chien, CC and Dewi Panjaitan, NS and Tseng, SW and Chen, HW and Yang, HC and Chen, YY and Soo, PC}, title = {Sucrose reduces biofilm formation by Klebsiella pneumoniae through the PTS components ScrA and Crr.}, journal = {Biofilm}, volume = {9}, number = {}, pages = {100269}, doi = {10.1016/j.bioflm.2025.100269}, pmid = {40130064}, issn = {2590-2075}, abstract = {The presence of sucrose at concentrations of 0.5-5% can either increase bacterial biofilms (Streptococcus mutans and Escherichia coli) or have no significant effect on biofilms (Pseudomonas aeruginosa and Staphylococcus aureus). However, our study revealed that 1 % sucrose reduced the biofilm formation by Klebsiella pneumoniae STU1. To explore the role of the phosphoenolpyruvate-dependent-carbohydrate: phosphotransferase system (PTS) in regulating this process, the scrA gene, which encodes the sucrose-specific EIIBC of the PTS, was deleted in K. pneumoniae to create a scrA mutant (ΔscrA). Thereafter, we observed that the biofilm formation and type 3 fimbriae production were not affected by sucrose in the ΔscrA while sucrose reduced these processes in the wild type. Furthermore, we discovered that Crr, the glucose-specific EIIA of PTS, was the primary but not the sole EIIA of ScrA in K. pneumoniae by sucrose fermentation test. In addition, deficiency of Crr reduced the biofilm formation in K. pneumoniae. Our proposed model suggests that, through the action of Crr in the absence of sucrose, the transcription of the mrk operon, which produces type 3 fimbriae, was increased, thereby influencing biofilm formation by K. pneumoniae and bacterial number in the gut of nematode. This observation differs from the regulation of polysaccharide and biofilm by sucrose in other bacteria. Our findings extend the understanding of the effects of sucrose on biofilm formation.}, }
@article {pmid40129480, year = {2025}, author = {Shrestha, A and Shringi, S and Shah, DH}, title = {Rapid serotype-independent differential detection of biofilm-positive and biofilm-negative Salmonella using Fourier transform infrared biotyping.}, journal = {One health (Amsterdam, Netherlands)}, volume = {20}, number = {}, pages = {101004}, doi = {10.1016/j.onehlt.2025.101004}, pmid = {40129480}, issn = {2352-7714}, abstract = {Foodborne illnesses caused by Salmonella represent a global one health challenge, with biofilm-forming strains exhibiting enhanced public health risks due to their ability to persist due to resistance to antimicrobial agents, disinfectants, and environmental stresses. While food-safety and public health investigation primarily focus on Salmonella identification and source tracing, they often overlook the biofilm-forming capacity of isolates, limiting their predictive value for risks posed by biofilm producing Salmonella. This study assessed fourier transform infrared (FTIR) biotyping for rapid serotype-independent differentiatial detection of biofilm-positive (BFP) from biofilm-negative (BFN) Salmonella. A total of 270 Salmonella strains representing 12 common serotypes were classified using three conventional biofilm assays (congo red and coomassie brilliant blue agar test, calcofluor test, and tube test) into true BFP (n = 80), true BFN (n = 64), and uncertain (n = 59) biofilm producers. Biofilm production for each group was also assessed with a microtiter plate assay. FTIR biotyping was applied to a subset of 115 strains (61 BFP, 54 BFN). Using spectral windows of 1180-1050 cm[-1] and 1400-1200 cm[-1], FTIR biotyping accurately differentiated BFP from BFN strains with 93.4 % sensitivity, 83.3 % specificity, and 88.6 % overall accuracy. FTIR biotyping differentiated 59 strains with uncertain biofilm status into BFN (n = 45) and BFP (n = 14). FTIR biotyping provides a rapid, sensitive and specific method for detection of biofilm-forming Salmonella strains. Incorporating FTIR biotyping for biofilm detection in current Salmonella surveillance and source-tracing protocols can enhance food safety risk assessments and improve Salmonella outbreak prevention.}, }
@article {pmid40128897, year = {2025}, author = {Fu, C and Wu, Y and Sørensen, SJ and Zhang, M and Dai, K and Gao, C and Qu, C and Huang, Q and Cai, P}, title = {The mitigation of spatial constraint in porous environments enhances biofilm phylogenetic and functional diversity.}, journal = {Microbiome}, volume = {13}, number = {1}, pages = {84}, pmid = {40128897}, issn = {2049-2618}, support = {42177283//National Natural Science Foundation of China/ ; 42225706//National Natural Science Foundation of China/ ; 2020YFC1806802//National Key Research Program of China/ ; 2662022ZHYJ001, 2662021JC012//Fundamental Research Funds for the Central Universities/ ; }, mesh = {*Biofilms/growth &amp; development ; Porosity ; *Phylogeny ; Bacteria/classification/genetics ; Microbiota ; Biodiversity ; }, abstract = {BACKGROUND: Porous environments constitute ubiquitous microbial habitats across natural, engineered, and medical settings, offering extensive internal surfaces for biofilm development. While the physical structure of the porous environment is known to shape the spatial organization of biofilm inhabitants and their interspecific interactions, its influence on biofilm community structure and functional diversity remains largely unknown. This study employed microfluidic chips with varying micropillar diameters to create distinct pore spaces that impose different levels of spatial constraints on biofilm development. The impact of pore spaces on biofilm architecture, community assembly, and metabolic functions was investigated through in situ visualization and multi-omics technologies.<br><br>RESULTS: Larger pore sizes were found to increase biofilm thickness and roughness while decreasing biofilm coverage over pore spaces. An increase in pore size resulted in reduced biofilm community evenness and increased phylogenetic diversity. Remarkably, biofilms in 300-&#x3bc;m pore spaces displayed the highest richness and the most complex and interconnected co-occurrence network pattern. The neutral model analysis demonstrated that biofilm assembly within different pore spaces was predominantly governed by stochastic processes, while deterministic processes became more influential as pore space increased. Exometabolomic analyses of effluents from the microfluidic chips further elucidated a significant correlation between the exometabolite profiles and biofilm community structure. The increased community richness in the 300-&#x3bc;m pore space was associated with the significantly higher exometabolome diversity.<br><br>CONCLUSIONS: Collectively, our results indicate that increased pore space, which alleviated spatial constraints on biofilm development, resulted in the formation of thicker biofilms with enhanced phylogenetic and functional diversity. Video Abstract.}, }
@article {pmid40128011, year = {2025}, author = {Sathiaseelan, A and Song, KP and Tan, HS and Choo, WS}, title = {Antibiofilm activity of Clitoria ternatea flowers anthocyanin fraction against biofilm-forming oral bacteria.}, journal = {FEMS microbiology letters}, volume = {}, number = {}, pages = {}, doi = {10.1093/femsle/fnaf035}, pmid = {40128011}, issn = {1574-6968}, abstract = {This study investigated the antibiofilm effects of Clitoria ternatea flowers anthocyanin fraction (AF) on Streptococcus mutans, Actinomyces viscosus and Aggregatibacter actinomycetemcomitans. AF was obtained using column chromatography, and liquid chromatography-mass spectrometry was employed for its characterization and identification. The crystal violet assay and scanning electron microscopy analysis revealed significant inhibition of early biofilm formation and destruction of preformed biofilms after AF treatment (0.94-15 mg mL-1). Anti-adhesion assay on acrylic teeth demonstrated that AF effectively hampered sucrose dependent and independent attachment. Importantly, growth curve and pH drop assays showed that AF inhibited pH reduction for all bacteria tested without hindering bacterial growth. Furthermore, the tetrazolium-based cytotoxicity assay indicated no toxicity towards normal human gingival fibroblasts (HGF-1) at 0.78-12.5 mg mL-1. These findings suggest C. ternatea anthocyanins are promising antibiofilm agents for oral biofilm control, acting during both initial formation and on mature biofilms.}, }
@article {pmid40127465, year = {2025}, author = {Song, Y and Zhu, J and Lv, Y and Liu, H and Kang, L and Shen, F and Zhang, C and Jiang, W and Yu, J and Wu, D}, title = {Temperature-Triggered Reversible Adhesion Hydrogel with Responsive Drug Release, Mild Photothermal Therapy, and Biofilm Clearance for Skin Infection Healing.}, journal = {ACS applied materials &amp; interfaces}, volume = {}, number = {}, pages = {}, doi = {10.1021/acsami.4c22647}, pmid = {40127465}, issn = {1944-8252}, abstract = {Bacterial infection gives rise to a hypoxic, H2O2-abundant, and acidic local microenvironment at the site of inflammation, which prevents the healing of skin tissues. In this work, gelatin and oxidized carboxymethyl cellulose were developed as the framework of hydrogels. Tannic acid and 3-formylphenylboronic acid served as small-molecule anchors. Through the introduction of multiple dynamic cross-linkings, the hydrogel was endowed with various functions. These functions encompassed mechanical compatibility with the skin, reversible adhesion characteristics, and rapid self-healing capabilities. In addition, nanoflower-like MnO2 microparticles loaded with berberine hydrochloride were embedded. MnO2 has the ability not only to kill bacteria through the photothermal effect (PTT) but also to catalyze the decomposition of H2O2 and release oxygen, effectively improving the inflammatory microenvironment. Remarkably, based on the drug/PTT synergistic strategy, the hydrogel exhibited significant antibacterial activity and biofilm removal ability under mild conditions (<50 °C), avoiding thermal damage to healthy tissues. Consequently, the hydrogels demonstrate favorable biocompatibility, significant cell proliferation, migration, angiogenesis, collagen deposition, and tissue regeneration. Therefore, the multifunctional antimicrobial hydrogel is expected to be a skin-friendly medical dressing with enormous potential in the treatment of skin and soft tissue infections.}, }
@article {pmid40126588, year = {2025}, author = {Duymaz, FZ and Budak, F and Okumuş, E}, title = {Genotypic analysis and biofilm formation of Acinetobacter baumannii clinical isolates.}, journal = {Acta microbiologica et immunologica Hungarica}, volume = {}, number = {}, pages = {}, doi = {10.1556/030.2025.02531}, pmid = {40126588}, issn = {1588-2640}, abstract = {Acinetobacter baumannii is a significant nosocomial pathogen recognized for its multidrug-resistance (MDR) and capacity to endure in hospital settings. This study aims to investigate the clonal relationships of A. baumannii isolates from diverse clinical samples, identify the sequence types of MDR isolates, and examine biofilm formation activity and biofilm-associated genes that contribute to persistence in hospital settings. A total of 90 A. baumannii isolates were analyzed. Bacterial identification and antibiotic susceptibility testing were conducted with MALDI-TOF MS and Vitek-2. REP-PCR was utilized to evaluate clonal connections, MLST was employed for specific isolates. Biofilm formation activity was assessed using the XTT reduction assay, and biofilm-associated genes were identified by PCR. REP-PCR revealed 29 genotypes, with Genotype A being identified as the endemic clone in 59% of isolates. Two isolates representing this genotype were found to belong to the ST2 clone. The majority of A. baumannii isolates possess biofilm-related genes and exhibit strong biofilm activity. In MDR isolates, ompA and csuE positivity were significantly higher than those non-MDR isolates (P = 0.003, P = 0.001). The csuE positive isolates were found to have significantly stronger biofilm activity than negative ones (P = 0.009). This study emphasizes the prevalence of a hospital-endemic, MDR A. baumannii genotype A, ST2 clone, and the genetic variability across isolates. No direct correlation was noted between MDR status and biofilm formation; however, some biofilm-related genes, notably csuE, were linked to stronger biofilm activity. These findings underscore the necessity for ongoing molecular surveillance and infection control measures to avert the dissemination of MDR A. baumannii in healthcare environments.}, }
@article {pmid40125431, year = {2025}, author = {Cai, R and Cheng, Q and Zhao, J and Zhou, P and Wu, Z and Ma, X and Hu, Y and Wang, H and Lan, X and Zhou, J and Tao, G}, title = {Sericin-Assisted Green Synthesis of Gold Nanoparticles as Broad-Spectrum Antimicrobial and Biofilm-Disrupting Agents for Therapy of Bacterial Infection.}, journal = {International journal of nanomedicine}, volume = {20}, number = {}, pages = {3559-3574}, doi = {10.2147/IJN.S494616}, pmid = {40125431}, issn = {1178-2013}, mesh = {*Gold/chemistry/pharmacology ; *Metal Nanoparticles/chemistry ; *Biofilms/drug effects ; *Sericins/chemistry/pharmacology ; Animals ; *Green Chemistry Technology ; Rats ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; Bacterial Infections/drug therapy ; Mice ; Staphylococcus aureus/drug effects ; Rats, Sprague-Dawley ; Wound Infection/drug therapy/microbiology ; Escherichia coli/drug effects ; Humans ; Male ; }, abstract = {BACKGROUND: Tens of millions of people die from wound infections globally each year, and nearly 80% of tissue infections are associated with bacterial biofilms. However, overuse of antibiotics can lead to bacterial resistance. Therefore, it is critical to develop simple and effective strategies to kill bacteria and remove biofilms.<br><br>METHODS: The present study used sericin as a reducing and stabilizing agent to synthesize sericin-gold nanoparticles (Ser-Au NPs) and tested its colloidal stability under different pH and salt concentration conditions. Subsequently, functional gold nanocomposites (Ser-Au@MMI) were synthesized by combining Ser-Au NPs with 2-mercapto-1-methylimidazole (MMI). The antimicrobial effect of Ser-Au@MMI was checked by MIC, antimicrobial activity test, and in vitro cytotoxicity was assessed using CCK-8 assay. In vitro anti-biofilm effect was observed by fluorescence microscopy and SEM. Finally, the anti-infective therapeutic efficacy of Ser-Au@MMI was determined in an in vivo rat-infected wound model.<br><br>RESULTS: Sericin as a reducing and stabilizing agent to synthesize Ser-Au NPs exhibited excellent colloidal stability under different pH and salt concentration conditions. The TEM, EDS, and XPS analyses confirmed the successful synthesis of Ser-Au@MMI. It exhibited higher antibacterial activity due to the synergistic effect of MMI and AuNP, which can achieve a bactericidal effect by destroying the integrity of bacterial cell walls and structure. In addition, Ser-Au@MMI10 (HAuCl4:MMI =1:10) concentration (64&#xa0;&#x3bc;g/mL) could effectively disrupt biofilms formed by four species of bacteria and kill them, including P. aeruginosa, B. subtilis, E. coli, and S. aureus, but was not cytotoxic to mouse fibroblasts (L929) cells. Infected wound modeling showed that Ser-Au@MMI10 accelerated infected wound healing in vivo.<br><br>CONCLUSION: Ser-Au@MMI nanocomposites are prepared through a facile and environmentally friendly strategy and have the advantages of excellent bactericidal effect and low toxicity, which has the potential for application as a broad-spectrum antimicrobial agent and biofilm disrupting agent in healthcare.}, }
@article {pmid40124935, year = {2025}, author = {Gerschler, S and Maaß, S and Gerth, P and Schulig, L and Wildgrube, T and Rockstroh, J and Wurster, M and Methling, K and Becher, D and Lalk, M and Schulze, C and Guenther, S and Schultze, N}, title = {Drosera rotundifolia L. as E. coli biofilm inhibitor: Insights into the mechanism of action using proteomics/metabolomics and toxicity studies.}, journal = {Biofilm}, volume = {9}, number = {}, pages = {100268}, doi = {10.1016/j.bioflm.2025.100268}, pmid = {40124935}, issn = {2590-2075}, abstract = {The successful sustainable cultivation of the well-known medicinal plant sundew on rewetted peatlands not only leads to the preservation of natural populations, but also provides a basis for the sustainable pharmaceutical use of the plant. The bioactive compounds of sundew, flavonoids and naphthoquinones, show biofilm-inhibiting properties against multidrug-resistant, ESBL-producing E. coli strains and open up new therapeutic possibilities. This study investigates the molecular mechanisms of these compounds in biofilm inhibition through proteomic analyses. Specific fractions of flavonoids and naphthoquinones, as well as individual substances like 7-methyljuglone and 2″-O-galloylhyperoside, are analyzed. Results show that naphthoquinones appear to act via central regulatory proteins such as OmpR and alter the stress response while flavonoids likely affect biofilm formation by creating an iron-poor environment through iron complexation and additionally influence polyamine balance, reducing intracellular spermidine levels. Further investigations including assays for iron complexation and analysis of polyamines confirmed the proteomic data. Safety evaluations through cytotoxicity tests in 3D cell cultures and the Galleria mellonella in vivo model confirm the safety of the extracts used. These findings highlight sundew as a promising candidate for new phytopharmaceuticals.}, }
@article {pmid40124492, year = {2025}, author = {Kakahi, FB and Martinez, JA and Avitia, FM and Volke, DC and Wirth, NT and Nikel, PI and Delvigne, F}, title = {Release of extracellular DNA by Pseudomonas sp. as a major determinant for biofilm switching and an early indicator for cell population control.}, journal = {iScience}, volume = {28}, number = {3}, pages = {112063}, doi = {10.1016/j.isci.2025.112063}, pmid = {40124492}, issn = {2589-0042}, abstract = {In Pseudomonas sp., the switch from planktonic to sessile state is driven by extracellular DNA release. We observed a subpopulation of cells associated with eDNA in the planktonic phase, as indicated by propidium iodide staining. Surprisingly, the size of this subpopulation was directly correlated with the overall biofilm-forming capacity of the population. This challenges the prevailing understanding of phenotypic switching and confirms that biofilm formation in Pseudomonas is a collective process governed by eDNA release. Automated flow cytometry tracked the process, and PI-positive cells were identified as an early indicator of biofilm formation. Automated glucose pulsing successfully reduced biofilm formation by interfering with PI-positive cell proliferation. This study provides insights into the collective determinants of biofilm switching in Pseudomonas putida and introduces a potential strategy for controlling biofilm formation.}, }
@article {pmid40123586, year = {2025}, author = {Javadi, K and Ahmadi, MH and Rajabnia, M and Halaji, M}, title = {Effects of Curcumin on Biofilm Production and Associated Gene in Multidrug-Resistant Acinetobacter baumannii Isolated from Hospitalized Patients.}, journal = {International journal of molecular and cellular medicine}, volume = {14}, number = {1}, pages = {567-575}, pmid = {40123586}, issn = {2251-9637}, abstract = {Multi-drug-resistant (MDR) Acinetobacter baumannii has become a major global healthcare concern due to its opportunistic infections and high antibiotic resistance. This investigation is intended to investigate curcumin's potential anti-bacterial and antibiofilm impacts on MDR A. baumannii and to present a promising strategy for fighting against infections caused by this pathogen. This cross-sectional investigation comprised 34 MDR A. baumannii clinical isolates. The Kirby-Bauer disc diffusion method evaluated the sensitivity of isolates to multifaceted anti-bacterial agents. The microdilution broth method quantified curcumin's minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC). The efficacy of curcumin in inhibiting MDR A. baumannii biofilm was assessed via 96-well microtiter plates. The expression of the biofilm-associated protein (bap) gene was evaluated by employing quantitative real-time PCR (qRT-PCR). Within the 34 MDR A. baumannii isolates, the highest resistance was noted for trimethoprim/sulfamethoxazole and ciprofloxacin, with all 34 isolates (100%) indicating resistance. The lowest resistance was noted for ampicillin/sulbactam, with 22 isolates (64.7%) exhibiting resistance. The MICs of curcumin ranged from 0.625 to 2.5 mg/ml, while the MBCs varied between 1.25 to 5 mg/ml. Curcumin reduced biofilm formation by 25% to 91%, depending on the concentration. In contrast to the untreated control, the average relative activity of the bap gene in MDR A. baumannii isolates declined by 62.07%. The findings indicate that curcumin demonstrates antimicrobial and anti-biofilm activities against MDR A. baumannii. The downregulation noted in the bap gene further supports the curcumin's anti-biofilm impact.}, }
@article {pmid40123553, year = {2025}, author = {Grzech-Leśniak, Z and Pyrkosz, J and Szwach, J and Lelonkiewicz, M and Pajączkowska, M and Nowicka, J and Matys, J and Grzech-Leśniak, K}, title = {In vitro evaluation of the effect of Er:YAG laser with a fractional PS04 handpiece on microbial biofilm survival.}, journal = {Dental and medical problems}, volume = {}, number = {}, pages = {}, doi = {10.17219/dmp/201941}, pmid = {40123553}, issn = {2300-9020}, abstract = {BACKGROUND: The oral microbiota consists of a diverse range of microorganisms, with Streptococcus spp. and Candida spp. frequently coexisting in oral infections.<br><br>OBJECTIVES: The aim of the study was to investigate the impact of Er:YAG (erbium-doped yttrium aluminum garnet) laser therapy, utilizing the PS04 fractional beam, on the in vitro growth and biofilm formation of clinical strains of Candida albicans, Candida glabrata and Streptococcus mutans.<br><br>MATERIAL AND METHODS: Singleand dual-species planktonic cultures and biofilms were exposed to an Er:YAG laser using a fractional PS04 handpiece. The effects of the laser were evaluated immediately after irradiation and 24 h post-irradiation by measuring colony-forming units per milliliter (CFU/mL). Biofilm biomass (singleand dual-species) was quantified using the crystal violet staining method. The study tested 2 sets of laser parameters: group 1 (T1): 1.5 W, 10 Hz, 30 s, 0.4 J/cm2, irradiance: 3.9 W/cm2; and group 2 (T2): 6.15 W, 10 Hz, 30 s, 1.6 J/cm2, irradiance: 16 W/cm2. Non-irradiated samples served as controls. The parameters were selected based on their frequent clinical use for snoring treatment and facial rejuvenation.<br><br>RESULTS: Candida albicans exhibited a significantly greater reduction under T2 settings in comparison to T1 (85.3 &#xb1;1.2% vs. 43.9 &#xb1;4.5%, respectively; p = 0.006) within single-species biofilms. For C. glabrata, a significant reduction was observed under T1 parameters (69.8 &#xb1;14.9%). Furthermore, S. mutans demonstrated a significantly higher reduction at T2 settings (97.1 &#xb1;0.6%) compared to T1 settings (81.1 &#xb1;19.6%), with statistically significant differences noted between S. mutans and both C. albicans and C. glabrata under T1, as well as between S. mutans and C. glabrata under T2. In dual-species biofilms, T2 fluence led to greater reductions in C. glabrata, S. mutans and C. albicans in mixed cultures (p < 0.05).<br><br>CONCLUSIONS: The Er:YAG laser, when used in conjunction with the PS04 handpiece, demonstrated a substantial reduction in the biofilms of C. albicans and C. glabrata. Higher fluence maintained reductions over a 24-h period, particularly in the case of C. glabrata and S. mutans. This study highlights the antifungal potential of low-fluence laser settings that are commonly used in facial aesthetic procedures and snoring treatment.}, }
@article {pmid40122434, year = {2025}, author = {Kanthenga, HT and Banicod, RJS and Ntege, W and Njiru, MN and Javaid, A and Tabassum, N and Kim, YM and Khan, F}, title = {Functional diversity of AI-2/LuxS system in Lactic Acid Bacteria: Impacts on Biofilm Formation and Environmental Resilience.}, journal = {Research in microbiology}, volume = {}, number = {}, pages = {104296}, doi = {10.1016/j.resmic.2025.104296}, pmid = {40122434}, issn = {1769-7123}, abstract = {A key component of microbial communication, autoinducer-2 (AI-2) signaling, affects several physiological processes, including environmental adaptation and biofilm formation in lactic acid bacteria (LAB). The multifarious contribution of AI-2, synthesized by LuxS, in improving biofilms and tolerance to hostile conditions in LAB has been investigated in this review. The evolutionary conservation and diversity of AI-2 are shown by a phylogenetic analysis of luxS gene among several LAB species. Furthermore, AI-2 signaling in LAB improves resistance to unfavorable environmental factors, including pH fluctuations, temperature extremes, and antimicrobial agents. Lactic acid bacteria could set off defenses against harmful impacts from environmental stresses.}, }
@article {pmid40122078, year = {2025}, author = {Ma, H and Liu, D and Song, C and Fan, H and Zhou, W and Zhao, H}, title = {Cefoxitin inhibits the formation of biofilm involved in antimicrobial resistance MDR Escherichia coli.}, journal = {Animal biotechnology}, volume = {36}, number = {1}, pages = {2480176}, doi = {10.1080/10495398.2025.2480176}, pmid = {40122078}, issn = {1532-2378}, mesh = {*Biofilms/drug effects ; *Cefoxitin/pharmacology ; *Escherichia coli/drug effects/physiology ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; *Drug Resistance, Multiple, Bacterial/drug effects ; Animals ; Cattle ; Escherichia coli Infections/veterinary/microbiology/drug therapy ; Gene Expression Regulation, Bacterial/drug effects ; Cattle Diseases/microbiology/drug therapy ; }, abstract = {The study investigates the relationship between biofilm formation and antibiotic resistance in Escherichia coli (E. coli) isolated from calves. Using biochemical and molecular methods, we identified the isolates and assessed their biofilm-forming ability through an improved crystal violet staining method. The minimum inhibitory concentrations (MICs) of 18 antibiotics against the isolates were determined using the broth microdilution method. The impact of cefoxitin on biofilm formation was analyzed using laser scanning confocal microscopy (LSCM). Additionally, qRT-PCR was employed to evaluate the expression levels of biofilm-related genes (luxS, motA, fliA, pfs, and csgD) in response to varying cefoxitin concentrations. Results indicated a significant correlation between antimicrobial resistance (AMR) and biofilm formation ability. Cefoxitin effectively reduced biofilm formation of multidrug-resistant E. coli isolates at 1/2 and 1 MIC, with enhanced inhibition at higher concentrations. The QS-related genes luxS, pfs, motA, and fliA were downregulated, leading to decreased csgD expression. At 1/2 MIC, csgD expression was significantly reduced. In conclusion, cefoxitin inhibits biofilm formation in multidrug-resistant E. coli by down-regulating key genes, offering a potential strategy to mitigate resistance and control infections in calves caused by biofilm-positive E. coli isolates.}, }
@article {pmid40121987, year = {2025}, author = {Wu, L and Li, P and Wang, G and Sijan, AH and Zhang, B}, title = {High-efficiency nitrogen and phosphorus removal for low C/N rural wastewater using a full-scale multi-stage A[2]O biofilm reactor combined with horizontal-vertical flow constructed wetlands system.}, journal = {Journal of environmental management}, volume = {380}, number = {}, pages = {125023}, doi = {10.1016/j.jenvman.2025.125023}, pmid = {40121987}, issn = {1095-8630}, abstract = {Rural wastewater treatment faces significant challenges in achieving stable effluent quality due to factors such as temperature fluctuations, variations in water quality and quantity, and low carbon-to-nitrogen (C/N) ratios. This study developed a full-scale, non-membrane, multi-stage anaerobic-anoxic-oxic (MSA[2]O) biofilm reactor integrated with horizontal-vertical flow constructed wetlands (HVCWs), which was operated continuously for approximately 320 days with an average flow of 11.9 m[3]/d in a rural area of northern China. Key parameters were optimized: hydraulic retention time (HRT) of 21-32 h, aeration rate of 4.0 m[3]/h, carbon source dosing at 1.25 L/h, PAC dosing at 0.55 L/h, and mixed liquor reflux ratio at 200 %. The system demonstrated high removal efficiencies for COD (74.2 %), NH4[+]-N (93.4 %), TN (90.6 %), and TP (86.3 %), consistently meeting the class 1A of GB18918-2002, China (COD ≤50 mg/L, NH4[+]-N ≤ 5 mg/L, TN ≤ 15 mg/L, TP ≤ 0.5 mg/L), even under challenging conditions such as low C/N (3.3) and rainy seasons. More than 70 % of nitrogen and phosphorus were removed in the MSA[2]O system. Microbial analysis revealed the enrichment of many functional bacteria. Proteobacteria play a key role in denitrification and phosphorus removal. Actinomycetes, Acidobacteria, and Firmicutes to nitrogen fixation and organic matter degradation. Nitrosomonas dominated ammonia oxidation, while Dechloromonas and Accumulibacter significantly contributed to phosphorus uptake. Seasonal variations in microbial diversity enabled consistent and highly efficient nutrient removal. The HVCWs system contributed 16.3 % of total phosphorus removal through selected plant species and phosphorus-absorbing modified ceramsite, ensuring effluent polishing and stability. With low operational costs ($0.12/m[3]), the integrated system provides an effective and scalable solution for rural wastewater treatment, delivering high-quality effluent with minimal energy consumption.}, }
@article {pmid40121868, year = {2025}, author = {Kim, YG and Jeon, H and Boya, BR and Lee, JH and Lee, J}, title = {Targeting biofilm formation in Candida albicans with halogenated pyrrolopyrimidine derivatives.}, journal = {European journal of medicinal chemistry}, volume = {290}, number = {}, pages = {117528}, doi = {10.1016/j.ejmech.2025.117528}, pmid = {40121868}, issn = {1768-3254}, abstract = {Growing concern over environmental contaminants, including pharmaceuticals and antifungal agents, highlights their role in promoting resistance and biofilm formation by microorganisms. Antifungal resistance, especially in drug-resistant Candida spp., poses a global threat, worsened by the widespread use of antifungal agents in both clinical applications and environmental contamination. This study investigates the antibiofilm properties of various halogenated pyrrolo pyrimidine derivatives, specifically 4-chloro-5-iodo-7H-pyrrolo[2,3-d]pyrimidine (10) and 2,4-dichloro-5-iodo-7H-pyrrolo[2,3-d]pyrimidine (16), against fluconazole-resistant C. albicans. Both compounds demonstrated strong biofilm inhibition, with 16 showing greater efficacy even at lower concentrations. qRT-PCR analysis revealed downregulation of key biofilm- and hyphae/germ tube-relating genes, including ALS3, HWP1, and ECE1, alongside upregulation of stress response and biofilm regulator genes such as CDR11, GST3, IFD6, UCF1, YWP1, and ZAP1, indicating complex regulatory responses to the treatments. Molecular docking analysis revealed that these compounds bind effectively to the binding cavity of the ALS3 protein, with halogen atoms playing a key role in stabilizing interaction. Compound 16 exhibited minimal cytotoxicity in Brassica rapa and Caenorhabditis elegans models, suggesting a favorable ADMET safety profile. Confocal microscopy analysis confirmed the compounds effectiveness in preventing biofilm formation when applied as biodegradable PLGA coatings on biomaterial surfaces. These findings suggest that 16 holds promise as a potent antifungal agent with reduced environmental impact, offering both efficacy and sustainability.}, }
@article {pmid40120989, year = {2025}, author = {Qin, S and Chen, W and Lin, Y and Tan, S and Liang, S and Liu, H and Zhang, Q}, title = {Effect of hydraulic retention time on the nitrogen removal performance of pure biofilm rotating biological contactor system inoculated with heterotrophic nitrification-aerobic denitrification bacteria and its corresponding mechanism.}, journal = {Bioresource technology}, volume = {}, number = {}, pages = {132428}, doi = {10.1016/j.biortech.2025.132428}, pmid = {40120989}, issn = {1873-2976}, abstract = {The traditional activated sludge biofilm system struggles with poor removal performance and long hydraulic retention time (HRT) in treating high ammonia nitrogen (NH4[+]-N) wastewater. To solve these problems, this study introduced a pure heterotrophic nitrification-aerobic denitrification (HN-AD) biofilm system which HN-AD bacteria were inoculated in the rotating biological contactor (PH-RBC), with free microorganisms discharged after biofilm formation. Under short HRT (12 h), PH-RBC exhibited 29.23 % and 31.03 % higher NH4[+]-N and total nitrogen (TN) removal than pure activated sludge biofilm RBC (PS-RBC) (the influent NH4[+]-N was 505 ± 45 mg/L). Flavobacterium and Azoarcus were crucial for nitrogen removal in the PH-RBC. Metabolic analysis revealed that genes CS and IDH3 are crucial for carbon metabolism, with dissimilatory nitrate reduction dominates nitrogen metabolism. Bugbase prediction indicated that decreasing HRT increased the presence of Potentially Pathogenic. This study provides a theoretical basis for using pure biofilm system in high NH4[+]-N wastewater treatment.}, }
@article {pmid40119885, year = {2025}, author = {Zhang, M and Zhu, Y and Li, X and Luo, X and Sun, H and Xiong, S and Lu, R and Zhang, Y}, title = {GepA, a GGDEF-EAL protein, regulates biofilm formation and swimming motility in Vibrio parahaemolyticus.}, journal = {Archives of microbiology}, volume = {207}, number = {5}, pages = {99}, pmid = {40119885}, issn = {1432-072X}, support = {QN2022044//Research Project of Nantong Health Commission/ ; JC2023045//Natural Science Foundation of Nantong University/ ; }, mesh = {*Biofilms/growth &amp; development ; *Vibrio parahaemolyticus/genetics/physiology/metabolism ; *Bacterial Proteins/genetics/metabolism ; *Cyclic GMP/metabolism/analogs &amp; derivatives ; *Gene Expression Regulation, Bacterial ; *Flagella/genetics/metabolism/physiology ; Protein Domains ; Phosphorus-Oxygen Lyases/metabolism/genetics ; Phosphoric Diester Hydrolases/metabolism/genetics ; Escherichia coli Proteins ; }, abstract = {Cyclic diguanylate monophosphate (c-di-GMP) is a second messenger that regulates multiple bacterial behaviors. It is synthesized by diguanylate cyclase (DGC) with the GGDEF domain, and degraded by phosphodiesterase (PDE) with the EAL or HD-GYP domain. The GepA (VP0117) protein in Vibrio parahaemolyticus contains both GGDEF and EAL domains, but its role remains unknown. This study found that deletion of the EAL domain or both the GGDEF and EAL domains in GepA increased intracellular c-di-GMP levels, enhanced biofilm formation, and inhibited polar flagellum-mediated swimming motility. Deletion of only the GGDEF domain had no such effects. Additionally, removing the EAL domain or both the GGDEF and EAL domains increased cpsA expression and decreased polar flagellar gene expression, while deleting the GGDEF domain alone had no impact on these genes. Overexpression of GepA or a GepA variant with a mutated GGDEF domain reduced biofilm formation but increased swimming motility. However, overexpression of GepA with a mutated EAL domain did not produce the expected phenotypic changes. In summary, GepA functions as a PDE to degrade c-di-GMP, thereby suppressing biofilm formation and enhancing swimming motility in V. parahaemolyticus.}, }
@article {pmid40119619, year = {2025}, author = {Scott, E and Bullerjahn, GS and Burkhart, CG}, title = {Targeting the Cutibacterium acnes Biofilm in Acne.}, journal = {International journal of dermatology}, volume = {}, number = {}, pages = {}, doi = {10.1111/ijd.17752}, pmid = {40119619}, issn = {1365-4632}, }
@article {pmid40118903, year = {2025}, author = {Francisco, M and Grau, R}, title = {Biofilm proficient Bacillus subtilis prevents neurodegeneration in Caenorhabditis elegans Parkinson's disease models via PMK-1/p38 MAPK and SKN-1/Nrf2 signaling.}, journal = {Scientific reports}, volume = {15}, number = {1}, pages = {9864}, pmid = {40118903}, issn = {2045-2322}, mesh = {Animals ; *Caenorhabditis elegans ; *Biofilms/drug effects/growth &amp; development ; *Caenorhabditis elegans Proteins/metabolism/genetics ; *Bacillus subtilis/physiology ; *Parkinson Disease/metabolism ; *p38 Mitogen-Activated Protein Kinases/metabolism ; *Dopaminergic Neurons/metabolism ; *Disease Models, Animal ; *NF-E2-Related Factor 2/metabolism ; *Signal Transduction ; *Oxidopamine ; *Transcription Factors/metabolism/genetics ; DNA-Binding Proteins/metabolism/genetics ; Humans ; alpha-Synuclein/metabolism/genetics ; Mitogen-Activated Protein Kinases ; }, abstract = {Parkinson's disease (PD) is a no-curable neurodegenerative disease of pandemic distribution for which only palliative treatments are available. A hallmark of PD is injury to dopaminergic neurons in the substantia nigra pars compacta. Here, we report that Caenorhabditis elegans colonized by biofilm-forming Bacillus subtilis is resistant to injury of dopaminergic neurons caused by treatment with the PD-related neurotoxin 6-hydroxydopamine (6-OHDA). Biofilm-forming B. subtilis-colonized C. elegans display dopamine-dependent behaviors indistinguishable from those of 6-OHDA-untreated worms colonized by gut commensal E. coli OP50. In C. elegans PD model strains with early dopaminergic neuron decay or overexpressing human alpha-synuclein, biofilm-forming B. subtilis colonization had neuroprotective effects and prevents alpha-synulcein aggregation, respectively. The B. subtilis-controlled insulin/IGF-1 signaling (ILS), whose downregulation prevents aging-related PD, is not involved in protecting against 6-OHDA-related injury. We demonstrate that biofilm-forming B. subtilis activates PMK-1 (p38 MAPK)/SKN-1 (Nrf2) signaling, which protects C. elegans from 6-OHDA-induced dopaminergic neuron injury.}, }
@article {pmid40118365, year = {2025}, author = {Sun, Z and Li, B and Liu, J}, title = {Synchronous vanadium bio-reduction/detoxification/recovery and nitrogen attenuation in a membrane aerated biofilm reactor.}, journal = {Environmental pollution (Barking, Essex : 1987)}, volume = {}, number = {}, pages = {126095}, doi = {10.1016/j.envpol.2025.126095}, pmid = {40118365}, issn = {1873-6424}, abstract = {The presence of both pentavalent vanadium [V(Ⅴ)] and nitrogen in wastewaters from vanadium smelting poses significant environmental challenges. However, it remains little in the way of continuous flow biological reactor to concurrently eliminated V(Ⅴ) and nitrogen in wastewaters. Herein, membrane-aerated biofilm reactor (MABR) system was designed to achieve simultaneous nitrification and denitrification (SND) alongside biological reduction, detoxification, and recovery of vanadium. Vanadium and nitrogen removal performances, solid-state characterization, microbial compositions and functional genes, and the mechanism related to the metabolism of vanadium and nitrogen were illuminated. Notably, we identified a potential role for biofilm-derived "secretion" in the transformation of V(Ⅴ) and nitrogen. Our findings revealed that the system achieved SND efficiency of 98.00 ± 0.57% and removed 91.10 ± 3.60% of total vanadium (TV) even at high influent V(Ⅴ) concentrations in continuous flow stage. Batch experiments implied that the conversion of NH4[+]-N was the limiting process of nitrogen removal in MABR system, and the extracellular polymeric substances (EPS) might play an important role in the conversion of V(Ⅴ) and nitrogen. V(Ⅴ) was reduced to V(Ⅳ), which was immobilized to biofilm and "secretion" by microbial surface functional groups, including C-O, O-C=O and -OH. Acinetobacter, Dechlorobacter, Denitratisoma and Nitrospira were verified as microbes associated with V(Ⅴ) and nitrogen metabolism. The abundance of functional genes pertaining to electron donor, electron transport, and electron acceptor systems increased under high V(V) stimulation. Collectively, the cooperation of biofilm and "secretion" ensured the intensive removal of vanadium and nitrogen. This study provides new insights into the concurrent removal of heavy metal and environmental nutrient.}, }
@article {pmid40118297, year = {2025}, author = {Habib, MB and Batool, G and Shah, NA and Muhammad, T and Akbar, NS and Shahid, A}, title = {Biofilm-Mediated Infections; Novel Therapeutic Approaches and Harnessing Artificial Intelligence for Early Detection and Treatment of Biofilm-Associated Infections.}, journal = {Microbial pathogenesis}, volume = {}, number = {}, pages = {107497}, doi = {10.1016/j.micpath.2025.107497}, pmid = {40118297}, issn = {1096-1208}, abstract = {A biofilm is a group of bacteria that have self-produced a matrix and are grouped together in a dense population. By resisting the host's immune system's phagocytosis process and attacking with anti-microbial chemicals such as reactive oxygen and nitrogen species, a biofilm enables pathogenic bacteria to evade elimination. One of the major problems in managing chronic injuries is treating wounds colonized by biofilms. These days, a major issue is the biofilms, which exacerbate infection pathogenesis and severity. Numerous investigators have already discovered cutting-edge methods for biofilm manipulation. Using phytochemicals is a practical tactic to control and prevent the production of biofilms. Numerous studies conducted in the last few years have demonstrated the antibacterial and antibiofilm qualities of nanoparticles (NPs) against bacteria, fungi, and protozoa. Because hydrogel has antibiofilm properties, it has been employed extensively in wound care recently. It may be removed with ease and without causing trauma. Today, artificial intelligence (AI) is being used to improve these tactics by providing customized treatment alternatives and predictive analytics. Artificial intelligence (AI) algorithms have the capability to examine extensive datasets and detect trends in biofilm formation and resistance mechanisms. This can aid in the creation of more potent antimicrobial drugs. AI models analyze complex datasets, predict biofilm formation, and guide the design of personalized treatment strategies by identifying resistance mechanisms and therapeutic targets with exceptional precision. This review provides an integrative perspective on biofilm formation mechanisms and their role in infections, highlighting the innovative applications of AI in this domain. By integrating data from diverse biological systems, AI accelerates drug discovery, optimizes treatment regimens, and enables real-time monitoring of biofilm dynamics. From predictive analytics to personalized care, we explore how AI enhances biofilm diagnostics and introduces precision medicine in biofilm-associated infections. This approach not only addresses the limitations of traditional methods but also paves the way for revolutionary advancements in infection control, antimicrobial resistance management, and improved patient outcomes.}, }
@article {pmid40117924, year = {2025}, author = {Sahu, S and Ghosal, P and Patel, H and Ghosal, PS}, title = {A comprehensive review on the treatment of pharmaceutically active compounds using moving bed biofilm reactor: A systematic meta-analysis coupled with meta-neural approach.}, journal = {Journal of environmental management}, volume = {380}, number = {}, pages = {124865}, doi = {10.1016/j.jenvman.2025.124865}, pmid = {40117924}, issn = {1095-8630}, abstract = {Pharmaceutically active compounds (PhACs) in wastewater pose challenges to cleaner environment due to their recalcitrance and toxicity, restricting the use of conventional treatment methods. On the other hand, advanced oxidation processes face technical complexity and financial constraints, which also discourage their applicability especially in large scale treatment system. Moving Bed Biofilm Reactor (MBBR) as an advanced biological treatment system has shown remarkable efficacy and cost-effectiveness in treating various PhACs. However, studies report significant variations in the efficacy of MBBR across removing different pollutants, leading to a complication in their performance assessment. The present review has targeted a systematic meta-analysis coupled with a meta-neural approach over the conventional bibliometric study. The statistical approach resolves the publication bias and associated formation of a pertinent databases, providing significant insights into MBBR's performance and process variables. The novel approach of meta-neural exhibited a multivariate prediction model with a significant F value of 257.66 and a p-value of <0.001 relating the role of various process parameters on the treatment efficacy. Among various pharmaceuticals, beta-blockers were eliminated most effectively by MBBR technology, with removal rates exceeding those of antibiotics, analgesics, antidepressants, fibrates, and anticonvulsants. Sensitivity analysis revealed the significant influence of the operating parameters on the outcome in the order of initial COD > HRT > filling ratio > pH > initial concentration of the contaminant. The present meta-analysis approach vis-à-vis meta-neural is instrumental for delineating the technology selection and design for removing PhACs or other emerging contaminants.}, }
@article {pmid40116703, year = {2025}, author = {Ghiraldelli, GHS and Iost, RM and Sedenho, GC and Colombo, RNP and Crespilho, FN}, title = {Yeast biofilm synapse: an intra-kingdom pathway to high-density current output in bioelectronic devices.}, journal = {Journal of materials chemistry. B}, volume = {}, number = {}, pages = {}, doi = {10.1039/d4tb02472a}, pmid = {40116703}, issn = {2050-7518}, abstract = {The quest to understand and harness microbial biofilms for energy generation has become increasingly important in the development of bioelectronic devices. Saccharomyces cerevisiae, a model organism, provides unique insights into how biofilms coordinate metabolic activities via extracellular polymeric substances (EPS). Beyond serving as a structural scaffold, EPS facilitates electrochemical signalling, enabling cellular communication and optimized electron transfer. This study demonstrates that encapsulating Saccharomyces cerevisiae in a hydrogel matrix enhances biofilm organization and significantly boosts bioelectricity generation, leveraging EPS as an electrochemical communication network. The concept of a "yeast synapse" is introduced, drawing parallels between microbial biofilms and synaptic signalling observed in higher organisms, with coordinated electron transfer and metabolic synchronization. It can drive advancements in bioelectrochemical system design and enhance the current output of sustainable bioelectronic devices.}, }
@article {pmid40116480, year = {2025}, author = {Bhattacharya, M and Scherr, TD and Lister, J and Kielian, T and Horswill, AR}, title = {Extracellular adherence proteins reduce matrix porosity and enhance Staphylococcus aureus biofilm survival during prosthetic joint infection.}, journal = {Infection and immunity}, volume = {}, number = {}, pages = {e0008625}, doi = {10.1128/iai.00086-25}, pmid = {40116480}, issn = {1098-5522}, abstract = {Biofilms are a cause of chronic, non-healing infections. Staphylococcus aureus is a proficient biofilm-forming pathogen commonly isolated from prosthetic joint infections that develop following primary arthroplasty. Extracellular adherence protein (Eap), previously characterized in planktonic or non-biofilm populations as being an adhesin and immune evasion factor, was recently identified in the exoproteome of S. aureus biofilms. This work demonstrates that Eap and its two functionally orphaned homologs EapH1 and EapH2 contribute to biofilm structure and prevent macrophage invasion and phagocytosis in these communities. Biofilms unable to express Eap proteins demonstrated increased porosity and reduced biomass. We describe the role of Eap proteins in vivo using a mouse model of S. aureus prosthetic joint infection. The Results suggest that the protection conferred to biofilms by Eap proteins is a function of biofilm structural stability that interferes with the leukocyte response to biofilm-associated bacteria.}, }
@article {pmid40116479, year = {2025}, author = {Tao, H and Zhang, W and Liu, J and Zhou, Y and Wang, G}, title = {The impact of the flagellar protein gene fliK on Helicobacter pylori biofilm formation.}, journal = {mSphere}, volume = {}, number = {}, pages = {e0001825}, doi = {10.1128/msphere.00018-25}, pmid = {40116479}, issn = {2379-5042}, abstract = {The biofilm structure of Helicobacter pylori is known to enhance its capabilities for antimicrobial resistance. This study aims to investigate the role of the flagellar hook length control protein gene fliK in the biofilm formation of H. pylori. Homologous recombination was employed to knock out the fliK gene in the H. pylori NCTC 11637 strain. The flagella of H. pylori were observed using transmission electron microscopy (TEM), whereas H. pylori motility and growth were examined through semi-solid agar assays and growth curve analyses, respectively. The bacterial biofilm and its constituents were visualized utilizing fluorescence confocal microscopy. Assessments of H. pylori adhesion to gastric mucosal cells, its vacuolar toxicity, and antibiotic resistance were evaluated using co-culture experiments and E-test methods. The fliK gene was successfully knocked out in H. pylori NCTC 11637. The ΔfliK mutant exhibited polyhook structures or lacked typical flagellar morphology, reduced mobility, and a slower bacterial growth rate compared with the wild-type strain. Fluorescence confocal microscopy revealed a decrease in the thickness of the biofilm formed by the ΔfliK strain, along with reductions in polysaccharide and DNA components. The deletion of fliK did not affect vacuolar toxicity or antibiotic resistance but did reduce the adhesive capacity of the bacterium to gastric mucosal cells. The deletion of the fliK gene significantly impairs H. pylori biofilm formation, leading to substantial decreases in biofilm components, bacterial growth, and adhesion capabilities. These findings underscore the importance of fliK in the pathogenicity of H. pylori.IMPORTANCEThe increasing antibiotic resistance of Helicobacter pylori has emerged as a global health concern, with biofilm formation serving as a crucial mechanism underlying this resistance. This study investigates the role of the fliK gene, which encodes the flagellar hook length control protein, in H. pylori biofilm formation. Furthermore, we examined the influence of fliK on H. pylori growth, motility, and cellular adhesion capabilities. Our findings elucidate the molecular mechanisms governing H. pylori biofilm formation and suggest potential therapeutic strategies for addressing H. pylori antibiotic resistance.}, }
@article {pmid40116065, year = {2025}, author = {Robinson, RL and Fisk, AT and Crevecoeur, S}, title = {Temporal and Depth-Driven Variability of Pelagic Bacterial Communities in Lake Erie: Biofilm and Plankton Dynamics.}, journal = {Environmental microbiology reports}, volume = {17}, number = {2}, pages = {e70079}, doi = {10.1111/1758-2229.70079}, pmid = {40116065}, issn = {1758-2229}, support = {ALLRP 555656-20//Natural Sciences and Engineering Research Council of Canada/ ; }, mesh = {*Biofilms/growth &amp; development ; *Lakes/microbiology ; *Plankton/genetics/classification/isolation &amp; purification ; *Bacteria/classification/genetics/isolation &amp; purification ; *RNA, Ribosomal, 16S/genetics ; Phylogeny ; Seasons ; Microbiota/genetics ; DNA, Bacterial/genetics ; Ecosystem ; Bacterial Physiological Phenomena ; Biodiversity ; }, abstract = {Despite constituting an important component of freshwater ecosystems, biofilm assemblages have remained relatively understudied compared to plankton, especially in freshwater systems such as the western basin of Lake Erie (WBLE). This study therefore aimed to elucidate temporal and vertical shifts of microbial communities of planktonic and biofilm growth on artificial substrates in the WBLE water column at discrete depths, investigating the overlap of shared taxa between community types. Sequencing of the 16S rRNA gene revealed concurrent biofilm-plankton samples shared a low percentage (~10%) of amplicon sequence variants (ASVs) indicating distinct communities between free-living and substrate-attached bacteria. Plankton communities did not significantly differ between surface and bottom depths (1 and 8 m), whereas biofilm communities differed between upper (1-4 m) and lower (5-8 m) water columns. Temporal variation in community composition was observed in biofilm, with early periods (June-July) showing significant dissimilarity followed by compositional convergence in late summer onwards (August-October). With the expansion of artificial infrastructure in aquatic systems, there is novel substrate material to observe spatiotemporal patterns of microbial colonisation throughout the pelagic zone. These results demonstrate the complexity of bacterial biofilm communities from plankton in freshwater, providing insight into microbial assembly through temporal succession and across depth.}, }
@article {pmid40115191, year = {2025}, author = {Shirmohammadpour, M and Mehrasbi, MR and Noshiranzadeh, N and Afshar, D and Mansori, K and Mirzaei, B}, title = {Investigation of the effect of anti-PIA/PNAG antibodies on biofilm formation in Escherichia coli.}, journal = {Frontiers in microbiology}, volume = {16}, number = {}, pages = {1552670}, pmid = {40115191}, issn = {1664-302X}, abstract = {Polysaccharide Intercellular Adhesin (PIA), a surface polysaccharide produced by Staphylococcus aureus and Staphylococcus epidermidis, is a compelling target for opsonic and protective antibodies against these bacteria. Escherichia coli has recently made an exopolysaccharide called poly-β(1,6)-N-acetylglucosamine (PNAG), biochemically indistinguishable from PIA. This study investigated the effect of antibodies generated against PNAG on biofilm formation and the opsonization activity of secreted antibodies in Escherichia coli. Following purification and structural confirmation of PIA polysaccharide from producing Staphylococcus epidermidis, the ability to inhibit biofilm and the function of secreted antibodies for the mentioned polysaccharide were evaluated using semi-quantitative methods in a mouse model. Subsequently, the opsonic activity of antibodies targeting Escherichia coli strain ATCC 25922 was evaluated. The extracted polysaccharide was confirmed using FTIR, NMR, and colorimetric methods, and the results showed that the purified PIA induced protective antibodies with 40.48% opsonization properties in E. coli. The sera of the PIA-immunized groups showed a significant increase in antibody production and protective IgG titer levels compared to the control group. Also, the antibodies produced showed a substantial difference in inhibiting biofilm production in vitro compared to non-immunized serum. Antibodies directed against PIA with a lethality of 40.48% showed a significant effect on the absence of biofilm formation in E. coli. Despite the opsonic properties of the antibodies for E. coli, the simultaneous impact of these antibodies on infections caused by S. epidermidis and E. coli may have a role that requires further investigation and studies in animal models.}, }
@article {pmid40111054, year = {2025}, author = {Ottaviano, E and Dei Cas, M and Ancona, S and Triva, F and Casati, S and Sisto, F and Borghi, E}, title = {Pilocarpine inhibits Candida albicans SC5314 biofilm maturation by altering lipid, sphingolipid, and protein content.}, journal = {Microbiology spectrum}, volume = {}, number = {}, pages = {e0298724}, doi = {10.1128/spectrum.02987-24}, pmid = {40111054}, issn = {2165-0497}, abstract = {UNLABELLED: Candida albicans filamentation and biofilm formation are key virulence factors tied to tissue invasion and antifungal tolerance. Pilocarpine hydrochloride (PHCl), a muscarinic receptor agonist, inhibits biofilm maturation, although its mechanism remains unclear. We explored PHCl effects by analyzing sphingolipid and lipid composition and proteomics in treated C. albicans SC5314 biofilms. PHCl significantly decreased polar lipid and ergosterol levels in biofilms while inducing phytoceramide and glucosylceramide accumulation. PHCl also induced reactive oxygen species and early apoptosis. Proteomic analysis revealed that PHCl treatment downregulated proteins associated with metabolism, cell wall remodeling, and DNA repair in biofilms to levels comparable to those observed in planktonic cells. Consistent with ergosterol reduction, Erg2 was found to be reduced. Overall, PHCl disrupts key pathways essential for biofilm integrity, decreasing its stability and promoting surface detachment, underscoring its potential as a versatile antifungal compound.<br><br>IMPORTANCE: Candida albicans filamentation and biofilm formation represent crucial virulence factors promoting fungus persistence and drug tolerance. The common eukaryotic nature of mammalian cells poses significant limitations to the development of new active nontoxic compounds. Understanding the mechanism underlying PHCl inhibitory activity on yeast-hypha transition, biofilm adhesion, and maturation can pave the way to efficient drug repurposing in a field where pharmaceutical investment is lacking.}, }
@article {pmid40110553, year = {2025}, author = {Mu, WB and Yao, LQ and Guo, ZY and Ma, YC and Wang, F and Yang, JH}, title = {Enhancing biofilm disruption and bactericidal efficiency using vancomycin-loaded microbubbles in sonodynamic therapy.}, journal = {JAC-antimicrobial resistance}, volume = {7}, number = {2}, pages = {dlaf045}, pmid = {40110553}, issn = {2632-1823}, abstract = {BACKGROUND: Periprosthetic joint infection (PJI) is a significant complication following arthroplasty, attributed to the biofilm formation. This study evaluates the effectiveness of vancomycin-loaded microbubbles (Van-MBs) in conjunction with ultrasound-targeted microbubble destruction (UTMD) on biofilm disruption and bactericidal efficiency.<br><br>METHODS: Van-MBs were prepared using the thin-film hydration method and characterized using microscopy, dynamic light scattering analysis, and high-performance liquid chromatography (HPLC). Confocal laser scanning microscopy (CLSM) was used to assess the penetration of Van and Van-MBs into biofilms. Biofilms were treated with Van, Van-MBs, UTMD, and Van-MBs&#x200a;+&#x200a;UTMD. CLSM and crystal violet staining were utilized to assess the morphology, viability, and biomass of the biofilms. Bacterial activity was examined through scanning electron microscopy (SEM) and plate counting, while gene expression was analyzed using quantitative real-time polymerase chain reaction (qRT-PCR).<br><br>RESULTS: The results demonstrated that Van-MBs penetrated deeper into methicillin-resistant Staphylococcus aureus (MRSA) biofilms compared with Van alone. The combination of Van-MBs and UTMD significantly reduced biofilm thickness, viability, and biomass. qRT-PCR analysis revealed that the Van-MBs&#x200a;+&#x200a;UTMD group exhibited lower transcription levels of the icaA gene, suggesting that the treatment disrupted biofilm formation by suppressing this key gene. SEM further confirmed the efficacy of the treatment, showing that Van-MBs&#x200a;+&#x200a;UTMD induced cytoplasmic shrinkage and separation of the outer and cytoplasmic membranes in MRSA cells, indicating substantial structural damage to the bacterial cells.<br><br>CONCLUSION: These findings demonstrate the potential of Van-MBs in combination with UTMD as an innovative approach to enhance antibiotic efficacy and eliminate biofilms in the treatment of PJI.}, }
@article {pmid40110395, year = {2025}, author = {Yoon, JH and Song, H and Lee, SY}, title = {Biofilm formation, slime production, and antibiotic susceptibility properties of the Bacillus cereus group isolated from fresh vegetables in the Republic of Korea.}, journal = {Food science and biotechnology}, volume = {34}, number = {6}, pages = {1525-1531}, pmid = {40110395}, issn = {2092-6456}, abstract = {This study aimed to characterize the ability of the Bacillus cereus group isolated from conventionally, organically or pesticide-freely grown vegetables to form biofilms with regard to cell surface hydrophobicity (CSH), slime production, and antibiotic susceptibility. Cellular properties (biofilm formation, CSH, and slime production) were measured using an in vitro microplate assay with crystal violet staining, adhesion to hydrocarbons assay, and Congo red broth method, respectively. Consequently, 16, 16, and 16 B. cereus strains were isolated from conventionally, organically, and pesticide-freely grown vegetables, respectively, and 16 (33%) B. cereus isolates were highly biofilm-positive producers. CSH values dramatically varied, ranging from 19 to 74%, among the B. cereus isolates. Additionally, 9, 8, and 8 B. cereus strains isolated from conventionally, organically, and pesticide-freely grown vegetables, respectively, were identified to be slime-positive producers. According to the disc diffusion method, 19 and 41 B. cereus isolates were highly resistant to ampicillin and penicillin, respectively.}, }
@article {pmid40107213, year = {2025}, author = {Lu, W and Guo, X and Wu, Y and Sun, S and Wang, Q and Guo, J and Zhao, HP and Lai, CY}, title = {Particulate methane monooxygenase and cytochrome P450-induced reactive oxygen species facilitate 17β-estradiol biodegradation in a methane-fed biofilm.}, journal = {Water research}, volume = {280}, number = {}, pages = {123501}, doi = {10.1016/j.watres.2025.123501}, pmid = {40107213}, issn = {1879-2448}, abstract = {Methane-fed biosystems have shown great potential for degrading various organic micropollutants, yet underlying molecular degradation mechanisms remain largely unexplored. In this study, we uncover the critical role of biogenic reactive oxygen species (ROS) in driving the degradation of 17β-estradiol (E2) within a methane-fed biofilm reactor. Metagenomic analyses confirm that aerobic methanotrophs, specifically Methylococcus and Methylomonas, are responsible for the efficient degradation of E2, achieving a degradation rate of 367.7 ± 8.3 μg/L/d. ROS scavenging in conjunction with enzyme inhibition experiments indicate that particulate methane monooxygenase (pMMO) and cytochrome P450 monooxygenase (CYP450) could generate hydroxyl radicals (•OH), which are the primary ROS involved in E2 degradation. Molecular dynamics simulations suggest that E2 can enter the active catalytic site of pMMO through electrostatic attraction. Four amino acid residues are found to form stable hydrogen bonds with E2, with a high binding free energy, indicating a high affinity for the substrate. Additionally, density functional theory calculations combined with transformation product analysis reveal that •OH targets carbon atoms on the benzene ring and the hydroxyl group attaches to the cyclopentane ring, primarily through hydrogen abstraction and hydroxylation reactions. This work provides critical insights into the mechanisms of E2 biodegradation in methane-fed systems and highlights the potential for optimizing microbial pathways to enhance the degradation of organic micropollutants from contaminated water.}, }
@article {pmid40106873, year = {2025}, author = {Liu, Y and Hu, L and Li, Z and Zhu, H and Dou, X and Ma, Y and Qin, X and Wang, X and Xia, X and Dong, Q}, title = {Elucidating the biofilm formation process, microstructure and functional gene expression of Listeria monocytogenes in beef juice.}, journal = {International journal of food microbiology}, volume = {434}, number = {}, pages = {111160}, doi = {10.1016/j.ijfoodmicro.2025.111160}, pmid = {40106873}, issn = {1879-3460}, abstract = {Listeria monocytogenes biofilm is recognized as a frequent cross-contamination source in the food industry, with raw beef and beef products as common food reservoirs. L. monocytogenes sequence types 9 (ST9) and ST8 are frequently isolated in meats and meat processing environment. In this study, beef juice was selected and compared to a laboratory medium (tryptone soy broth with 0.6 % yeast extract, TSB-YE). The purpose of this work was to investigate the effect of beef juice on the biofilm formation of ST9 and ST8 strains, including biofilm microstructure and modelling the biofilm formation process. Then the expression of biofilm functional genes in two culture media was also investigated. L. monocytogenes ST9 and ST8 can form a dense three-dimensional structure biofilm with multilayers of cells in beef juice after 48 h of incubation, but both strains formed a monolayer biofilm structure in TSB-YE. The ST9 strain developed more sessile cells on the stainless-steel surfaces than the ST8 strain under the same culture conditions. The Logistic model showed a good fit for with the biofilm formation process, and the estimated model parameters in beef juice and TSB-YE were considerably different. Under the same conditions, the maximum specific biofilm formation rate (μmax) in beef juice was higher than that in TSB-YE. This indicated that beef juice can facilitate the biofilm formation of L. monocytogenes, suggesting that the particles in beef juice act as a surface conditioner to support attachment. However, the maximum counts of L. monocytogenes biofilm formed on stainless steel coupon (Ymax) in beef juice was smaller than that in TSB-YE. The ST9 strain exhibited a stronger biofilm formation ability than the ST8 strain, and this was consistent with the scanning electron microscopy images. In the corresponding culture suspensions, the number of adherent cells increases with the number of planktonic cells. Moreover, the expression of biofilm functional genes was significantly different in the two culture media. Compared to biofilm cultured in TSB-YE, the expression of the agrA gene of biofilm in beef juice was significantly down-regulated for both the ST9 and the ST8 strains, and the expression of the inlB and the actA genes were dramatically up-regulated for the ST8 strain. Our results suggested that beef juice promotes biofilm formation of L. monocytogenes in meat processing and provide new insights into controlling biofilm.}, }
@article {pmid40106563, year = {2025}, author = {Fang, Z and Yang, X and Shang, L}, title = {Microfluidic-derived montmorillonite composite microparticles for oral codelivery of probiotic biofilm and postbiotics.}, journal = {Science advances}, volume = {11}, number = {12}, pages = {eadt2131}, doi = {10.1126/sciadv.adt2131}, pmid = {40106563}, issn = {2375-2548}, mesh = {*Probiotics/administration &amp; dosage/pharmacology ; *Bentonite/chemistry/pharmacology/administration &amp; dosage ; Animals ; *Biofilms/drug effects ; Mice ; Administration, Oral ; Lactobacillus acidophilus ; Microfluidics/methods ; Gastrointestinal Microbiome/drug effects ; Humans ; Disease Models, Animal ; Colitis, Ulcerative/therapy ; }, abstract = {Oral delivery of probiotics has shown promising effects in modulating the gut microbiota and treating ulcerative colitis (UC). However, the therapeutic efficacy is restricted by gastrointestinal assaults, poor mucosal adhesion, and single therapeutic modality. Here, we developed acid-resistant, gut-environment-responsive composite microparticles based on microfluidic electrospray for the oral codelivery of probiotic [Lactobacillus acidophilus (LA)] biofilm and postbiotics (indole-3-propionic acid). Montmorillonite was selected for supporting biofilm formation due to its cation-exchange capability and clearly defined biosafety. The montmorillonite-LA biofilm was effectively protected by the microparticles and markedly improved the intestinal retention. Upon oral administration, the composite microparticles notably alleviated colitis in mice, including reducing the inflammatory response, improving intestinal barrier function, and modulating the gut microbiota. Consequently, the composite microparticles show high potential for enhancing probiotic delivery efficacy and present a promising strategy for UC treatment.}, }
@article {pmid40106189, year = {2025}, author = {Wang, S and Wang, Y and Cheng, C and Zhang, H and Jin, J and Pang, X and Song, X and Xie, Y}, title = {PotF Affects the Antibacterial Activity of Plantaricin BM-1 Against Escherichia coli K12 by Modulating Biofilm Formation and Cell Membrane Integrity.}, journal = {Probiotics and antimicrobial proteins}, volume = {}, number = {}, pages = {}, pmid = {40106189}, issn = {1867-1314}, support = {11000024T000002961733//Classification Development of Beijing Municipal Universities-Construction of Urban Agriculture and Forestry Characteristic Teacher Team/ ; }, abstract = {Plantaricin BM-1 exhibits antibacterial activity against Escherichia coli; however, the underlying mechanism remains unclear. This study aimed to investigate the function of PotF, a putrescine-binding protein, in regulating the antibacterial activity of plantaricin BM-1 against E. coli K12. The antibacterial activity of plantaricin BM-1 against E. coli K12 and JW0838 cells was assessed using growth curves. The differences in biofilm formation between the two E. coli strains were evaluated by crystal violet staining and confocal laser scanning microscopy. The effects of plantaricin BM-1 on E. coli morphology and cell membrane integrity were investigated by electron microscopy and lactate dehydrogenase release assays. Proteomics was used to screen for differentially expressed proteins (DEPs) that are potentially involved in regulating the antibacterial mechanism. The null mutation of potF enhanced the antibacterial effects of plantaricin BM-1 on E. coli, and caused a significant decrease (p < 0.05) in the biofilms of E. coli JW0838. The plantaricin disrupted the cell membrane of E. coli JW0838. Proteomic analysis revealed that potF mutation significantly affected several DEPs involved in biofilm formation. Plantaricin BM-1 exhibited significantly enhanced antibacterial activity against biofilm-associated gene mutants compared to wild-type E. coli K12. These findings enhance our understanding of the bacteriostasis of class IIa bacteriocins against Gram-negative microorganisms.}, }
@article {pmid40104604, year = {2025}, author = {Nayak, D and Mishra, AK and Biswas, K and Sen, A and Malakar, C and Panda, J and Kungwani, NA and Rustagi, S and Panda, BP and Mohanta, YK}, title = {Mangrove pneumatophores as biocatalysts for the fabrication of silver nanoparticles and their potential applications against biofilm formation and hepatic carcinoma.}, journal = {Nanoscale advances}, volume = {}, number = {}, pages = {}, pmid = {40104604}, issn = {2516-0230}, abstract = {The current study demonstrates the biogenic synthesis of silver nanoparticles using the pneumatophores of Acanthus ilicifolius (AiP-AgNPs), which is cost-effective and biocompatible. A. ilicifolius possesses remarkable features to endure the harshest conditions for its entire life cycle and generates secondary metabolites for its sustainability in hostile mangrove ecosystems. The presence of a prominent UV-visible absorption band at 420 nm supported the distinct color change inference for the synthesized AiP-AgNPs. The size of the synthesized AiP-AgNPs was determined to be ∼15 nm through field emission-scanning electron microscopy (FE-SEM), transmission electron microscopy (cryo-TEM), and atomic force microscopy (AFM). The presence of secondary metabolites such as 2-bromo-1,1-dichloroethene, hemin and N-(sulfanylacetyl)-l-seryl-l-argininamide was indicated by prominent peaks in liquid chromatography, suggesting their probable roles in the synthesis of AgNPs. The synthesized AiP-AgNPs demonstrated a distinct zone of inhibition against Pseudomonas aeruginosa (15.33 mm), Vibrio cholerae (9.83 mm), and Bacillus subtilis (12 mm). They also exhibited concentration-dependent antioxidant activity in DPPH, nitric oxide, and hydrogen peroxide scavenging assays. The anticancer potential of the synthesized AiP-AgNPs against HepG2 hepatocarcinoma cells determined through MTT colorimetric assay and flow cytometry revealed their dose-dependent cytotoxicity with the occurrence of the sub-G0 phase (25.6%). Subsequent analysis using fluorescence microscopy, DNA damage, comet assay, and migration assay indicated that AiP-AgNPs hold significant potential and the ability to serve as a therapeutic candidate to pave the way for further in-depth investigations for pre-clinical and clinical research purposes.}, }
@article {pmid40104489, year = {2025}, author = {Modak, S and Mane, P and Patil, S}, title = {A Comprehensive Phenotypic Characterization of Biofilm-Producing Coagulase-Negative Staphylococci: Elucidating the Complexities of Antimicrobial Resistance and Susceptibility.}, journal = {Cureus}, volume = {17}, number = {2}, pages = {e79039}, pmid = {40104489}, issn = {2168-8184}, abstract = {Background Coagulase-negative staphylococci (CoNS) have emerged as significant pathogens in nosocomial infections, particularly in bloodstream infections and individuals linked to embedded therapeutic devices. CoNS predominantly affects immunocompromised or debilitated patients. Additionally, individuals with medical indwelling devices, such as a catheter for the urinary tract, valves for the cardiovascular system, pacemakers, and prosthetic joints, should receive medical attention. As a result of the organism's evolving resistance to multiple antibiotics, managing CoNS infections is becoming increasingly challenging. The formation of biofilms is a key factor contributing to the pathogenicity and antimicrobial resistance of CoNS, complicating treatment efforts and the resolution of infections. Aim The aim of this study is to identify CoNS species, examine their biofilm production, and evaluate their resistance to antibiotics. Materials and methods A cross-sectional study was conducted on patients admitted to the Microbiology Department at Krishna Hospital, Karad. Clinical samples included the following: blood, pus, urine, sputum, endotracheal tube aspirate, high vaginal swab, and central venous catheter. Results The occurrence of coagulase-negative Staphylococcus across the range of clinical samples consisted of blood (61 isolates, 75.3%), pus (seven isolates, 8.6%), urine (six isolates, 7.4%), sputum (three isolates, 3.7%), endotracheal tubes (two isolates, 2.5%), and high vaginal swab and central venous catheter (one isolate (1.2%) each). The most often isolated species was Staphylococcus haemolyticus (35 isolates, 43.2%) followed by Staphylococcus epidermidis (22 isolates, 27.2%) and Staphylococcus hominis (12 isolates, 14.8%). We assessed the production of biofilms using Congo red agar, with 62 isolates (76.5%) demonstrating biofilm formation. Among these, S. haemolyticus was the predominant species exhibiting biofilm production, with 29 isolates (46.8%) testing positive. This was followed by S. epidermidis with 19 isolates (30.7%) and S. hominis with nine isolates (14.5%). Conclusion The results of antibiotic susceptibility tests revealed multidrug resistance, with most isolates showing a high level of susceptibility to linezolid (84%) and complete resistance to penicillin. These findings highlight the clinical implications of limited treatment options and the need for alternative therapies, such as linezolid, in managing infections caused by coagulase-negative staphylococci.}, }
@article {pmid40102767, year = {2025}, author = {Eidaroos, NH and Algammal, AM and Mohamaden, WI and Alenzi, AM and Alghamdi, S and Kabrah, A and El-Mahallawy, HS and Eid, HM and Algwad, AA and Asfor, SA and Neubauer, H and Moawad, AA and El-Tarabili, RM}, title = {Virulence traits, agr typing, multidrug resistance patterns, and biofilm ability of MDR Staphylococcus aureus recovered from clinical and subclinical mastitis in dairy cows.}, journal = {BMC microbiology}, volume = {25}, number = {1}, pages = {155}, pmid = {40102767}, issn = {1471-2180}, mesh = {Animals ; Cattle ; *Biofilms/growth &amp; development/drug effects ; *Mastitis, Bovine/microbiology ; *Staphylococcal Infections/microbiology/veterinary ; Female ; *Bacterial Proteins/genetics ; *Staphylococcus aureus/genetics/drug effects/pathogenicity/isolation &amp; purification ; *Drug Resistance, Multiple, Bacterial/genetics ; *Anti-Bacterial Agents/pharmacology ; *Milk/microbiology ; *Virulence Factors/genetics ; Microbial Sensitivity Tests ; Methicillin-Resistant Staphylococcus aureus/genetics/drug effects/pathogenicity/isolation &amp; purification ; Trans-Activators/genetics ; Virulence/genetics ; Enterotoxins/genetics ; }, abstract = {BACKGROUND: Bovine mastitis caused by Staphylococcus aureus is considered a public health threat globally. Herein, we aimed to investigate the occurrence, agr typing, antimicrobial resistance patterns, biofilm production, and PCR-based detection of the virulence, biofilm, adhesion, and enterotoxins genes of S. aureus strains recovered from clinical and subclinical bovine mastitis.<br><br>RESULTS: The prevalence of S. aureus in the examined milk samples was 44.4%. Besides, 95% of the retrieved S. aureus strains were identified as MRSA. Herein, all the tested isolates were biofilm producers. PCR revealed that 85% of the retrieved S. aureus strains were positive for the agr I gene. Furthermore, the clfB, clfA, fnbB, fnbA, and cna genes were detected with a prevalence of 100%, 80%, 60%, 55%, and 30%, respectively. Also, all the tested S. aureus strains were positive for the coa gene (100%). Besides, 92.5% and 85% of the recovered strains harbored the lukF and spa genes, respectively. In addition, the prevalence of the hla, hlb, and hlg hemolysin genes was 70%, 50%, and 35%, respectively. Among the enterotoxin genes, the seb gene was detected in 30% of the tested strains. The prevalence of eno and icaA biofilm genes was 95% in the tested strains. Moreover, 15% of S. aureus strains were MDR to 8 antimicrobial agents and harbored the&#xa0;mecA, ermC, and ermB genes. As well, 12.5% of S. aureus strains were MDR to 8 antimicrobial agents and carried the mecA, ermC, ermB, tetK, and tetM genes. Also, 5% of S. aureus strains were XDR to 11 antimicrobial agents and carried the&#xa0;mecA, ermC, and ermB genes.<br><br>CONCLUSIONS: The existence of MDR and XDR MRSA strains in bovine milk is a public health hazard. The mecA, ermC, ermB, tetK, and tetM resistance genes and the coa, clfB, eno, icaA, lukF, spa, clfA, and hla virulence genes are commonly associated with the MDR and XDR MRSA strains. Moreover, the seb gene was the predominant enterotoxin gene in the MRSA strains recovered from milk.}, }
@article {pmid40102466, year = {2025}, author = {Xu, Y and Wang, L and Guo, D and Wang, Y and Liu, X and Sun, Y and Wang, R and Sun, L and Jiang, P and Liu, Q and Wang, B and Yan, M and Zhao, Y}, title = {Baohuoside I targets SaeR as an antivirulence strategy to disrupt MRSA biofilm formation and pathogenicity.}, journal = {NPJ biofilms and microbiomes}, volume = {11}, number = {1}, pages = {45}, pmid = {40102466}, issn = {2055-5008}, support = {YDZJ202401113ZYTS//Jilin Provincial Science and Technology Development Plan/ ; YDZJ202501ZYTS177//Jilin Provincial Science and Technology Development Plan/ ; 2024069//Jilin Provincial Traditional Chinese Medicine Science and Technology Program/ ; 20240207010CX//Jilin Provincial Scientific and Technological Development Program/ ; U22A20340//National Natural Science Foundation of China/ ; XZ202301ZY0011G//the Department of Science and Technology of the Tibet Autonomous Region, China/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Methicillin-Resistant Staphylococcus aureus/drug effects/pathogenicity ; Animals ; *Bacterial Proteins/metabolism/genetics ; *Staphylococcal Infections/drug therapy/microbiology ; Virulence/drug effects ; *Virulence Factors/metabolism ; Rats ; Anti-Bacterial Agents/pharmacology ; Gene Expression Regulation, Bacterial/drug effects ; Moths/microbiology ; Transcription Factors/metabolism/genetics ; Disease Models, Animal ; Flavonols/pharmacology ; Rats, Sprague-Dawley ; }, abstract = {The emergence of methicillin-resistant Staphylococcus aureus (MRSA) represents a critical global health challenge, making the SaeRS two-component system (TCS), a key regulator of S. aureus virulence, an ideal target for novel therapeutic approaches. In this study, virtual screening and thermal shift assays identified Baohuoside I (BI), a flavonol glycoside, as a potent inhibitor of the SaeR response regulator. BI significantly attenuated S. aureus pathogenicity without bactericidal effects, suppressing the expression of key virulence factors, such as hemolysin A (Hla) and Panton-Valentine leukocidin (PVL), while modulating immune evasion pathways. Additionally, BI disrupted biofilm formation, promoting the development of porous, less structured biofilms. Biochemical assays, including EMSA, CETSA, fluorescence quenching, and SPR, confirmed strong binding interactions between SaeR and BI. In vivo, BI demonstrated therapeutic efficacy in Galleria mellonella and rat MRSA models. These findings establish BI as a promising lead for nonbactericidal therapies to combat MRSA infections and mitigate resistance.}, }
@article {pmid40102278, year = {2025}, author = {Lazrak, K and Tazart, Z and Nothof, M and Filker, S and Hakkoum, Z and Kaczmarek, N and Berger, E and Mouhri, K and Loudiki, M}, title = {Assessment of the short-term salinity effect on algal biofilm through field transfer in the Drâa river (Southeastern Morocco) using metabarcoding and morphological analyses.}, journal = {Environmental monitoring and assessment}, volume = {197}, number = {4}, pages = {424}, pmid = {40102278}, issn = {1573-2959}, mesh = {Morocco ; *Salinity ; *Biofilms ; *Rivers/microbiology/chemistry ; *Environmental Monitoring ; *Microalgae/physiology ; *Diatoms/physiology ; Biomass ; DNA Barcoding, Taxonomic ; Ecosystem ; }, abstract = {As a result of human activities and climate change, salinity levels have risen considerably in many of the world's rivers, particularly in arid and semi-arid areas. This freshwater salinization primarily affects microalgal biofilms, the primary producers in aquatic ecosystems. This study is aimed at assessing short-term salinity effects on benthic algal communities in the Drâa river, Morocco, using biofilm field-transfer experiments. Artificial substrates were initially positioned in three sites of the Drâa river with different salinity levels. After 4 weeks, the biofilm-colonized substrates were transferred from one site to another in both directions. After a further 4 weeks, the algal biofilms were sampled to assess their community composition, alpha and beta diversity, and biomass in response to salinity changes using molecular and morphological analyses. Transferring biofilms from low-salt to saline sites significantly reduced biomass but increased it in the reverse transfer. Eliminating certain sensitive microalgae taxa decreased alpha diversity in all biofilm transfers from low-salt sites to the most saline one. Biofilm diversity increased significantly in the opposite transfer. Significant changes were observed in biofilm composition when transferred into saltwater showing an increase in halophilic and euryhaline diatom taxa. In contrast, transfers from saltwater sites to low-salt sites increased oligohaline diatom species. As a result, increasing salinity reduced algal biomass and diversity, while decreasing salinity caused the opposite effect. These results can help predict the salinity variations effects on benthic algae, highlight the potential dangers of increased river salinization, and promote salinity reduction in aquatic ecosystems subject to secondary salinization.}, }
@article {pmid40102043, year = {2025}, author = {Shental-Isaacs, M and Horev, G and Dosoretz, CG}, title = {Evaluation of biofilm carrier colonisation in a deammonification moving-bed biofilm reactor.}, journal = {Environmental technology}, volume = {}, number = {}, pages = {1-14}, doi = {10.1080/09593330.2025.2475522}, pmid = {40102043}, issn = {1479-487X}, abstract = {This study focused on the evaluation and characterisation of carrier colonisation of a deammonification moving-bed biofilm reactor (dMBBR) at a low carrier-inoculation ratio (≤5%v/v), applying multiple methodologies. The dMBBR (5 L working volume) was filled with Aqwise carriers (50%v/v filling ratio) and fed with synthetic feedstock. Carrier colonisation was differentially tracked using grey colour for new carriers and white colour for pre-colonised seed carriers. The reactor operated for 190 days at a nitrogen loading of 125-140 gN/m[3]/d. Multivariant heatmap analysis of the process parameters indicated stable deammonification performance from day 85 onwards albeit some occasional malfunctions occurred, with NH4[+] and total nitrogen removal rates amounting to 85% and 61%, respectively. Biofilm development on new carriers, evaluated by bulk density measurements via pycnometry, proved to be a reliable, simple, and non-destructive methodology. Anammox of genus Candidatus Brocadia and ammonia oxidising bacteria of genus Nitrosomonas were well established on the new carriers, in line with theoretical and empirical specific activity tests. This multi-parameter evaluation provides a broad insight into deammonification biomass development on the carriers and may assist in shortening the start-up period of dMBBRs.}, }
@article {pmid40101913, year = {2025}, author = {Liu, T and Lin, J and Zheng, X}, title = {[Role of antibiotic delivery system targeting bacterial biofilm based on ε-poly- L-lysine and cyclodextrin in treatment of bone and joint infections].}, journal = {Zhongguo xiu fu chong jian wai ke za zhi = Zhongguo xiufu chongjian waike zazhi = Chinese journal of reparative and reconstructive surgery}, volume = {39}, number = {3}, pages = {362-369}, doi = {10.7507/1002-1892.202412031}, pmid = {40101913}, issn = {1002-1892}, mesh = {*Biofilms/drug effects ; Animals ; Rats ; *Polylysine/chemistry ; *Anti-Bacterial Agents/pharmacology/administration &amp; dosage ; *Rats, Sprague-Dawley ; Male ; *Cyclodextrins/chemistry ; Mice ; *Microbial Sensitivity Tests ; Staphylococcus aureus/drug effects ; Humans ; Drug Delivery Systems ; Staphylococcal Infections/drug therapy ; }, abstract = {OBJECTIVE: To explore the mechanism of antibiotic delivery system targeting bacterial biofilm with linezolid (LZD) based on ε-poly- L-lysine (ε-PLL) and cyclodextrin (CD) (ε-PLL-CD-LZD), aiming to enhance antibiotic bioavailability, effectively penetrate and disrupt biofilm structures, and thereby improve the treatment of bone and joint infections.<br><br>METHODS: &#x3b5;-PLL-CD-LZD was synthesized via chemical methods. The grafting rate of CD was characterized using nuclear magnetic resonance. In vitro biocompatibility was evaluated through live/dead cell staining after co-culturing with mouse embryonic osteoblast precursor cells (MC3T3-E1), human umbilical vein endothelial cells, and mouse embryonic fibroblast cells (3T3-L1). The biofilm-enrichment capacity of &#x3b5;-PLL-CD-LZD was assessed using Staphylococcus aureus biofilms through enrichment studies. Its biofilm eradication efficacy was investigated via minimum inhibitory concentration (MIC) determination, scanning electron microscopy, and live/dead bacterial staining. A bone and joint infection model in male Sprague-Dawley rats was established to validate the antibacterial effects of &#x3b5;-PLL-CD-LZD.<br><br>RESULTS: In &#x3b5;-PLL-CD-LZD, the average grafting rate of CD reached 9.88%. The cell viability exceeded 90% after co-culturing with three types cells. The strong biofilm enrichment capability was observed with a MIC of 2 mg/L. Scanning electron microscopy observations revealed the effective disruption of biofilm structure, indicating potent biofilm eradication capacity. In vivo rat experiments demonstrated that &#x3b5;-PLL-CD-LZD significantly reduced bacterial load and infection positivity rate at the lesion site (P<0.05).<br><br>CONCLUSION: The &#x3b5;-PLL-CD antibiotic delivery system provides a treatment strategy for bone and joint infections with high clinical translational significance. By effectively enhancing antibiotic bioavailability, penetrating, and disrupting biofilms, it demonstrated significant anti-infection effects in animal models.}, }
@article {pmid40099915, year = {2025}, author = {Rooney, LJP and Marshall, A and Tunney, MM and Tabaei, SR}, title = {Phenylboronic Acid-Modified Polyethyleneimine: A Glycan-Targeting Anti-Biofilm Polymer for Inhibiting Bacterial Adhesion to Mucin and Enhancing Antibiotic Efficacy.}, journal = {ACS applied materials &amp; interfaces}, volume = {}, number = {}, pages = {}, doi = {10.1021/acsami.4c20874}, pmid = {40099915}, issn = {1944-8252}, abstract = {Bacterial biofilms present significant therapeutic challenges due to their resistance to conventional antimicrobial treatment. Mucins typically serve as a protective barrier against pathogens, yet certain bacteria, such as Pseudomonas aeruginosa (P. aeruginosa), can exploit these glycoproteins as attachment sites for biofilm formation. This study introduces boronic acid-functionalized polyethyleneimine (PEI-BA) as a promising antibiofilm agent that effectively blocks bacterial adhesion to mucin-rich surfaces. Through the multivalent presentation of boronic acid groups, PEI-BA reversibly forms boronate ester bonds with mucin glycans, creating a protective barrier. Our findings show that PEI-BA prevents bacterial attachment through a nonbactericidal mechanism, potentially reducing the risk of resistance development. Notably, PEI-BA synergizes with a conventional antibiotic, tobramycin, significantly enhancing biofilm inhibition compared to either treatment alone. Systematic evaluation of PEI-BA formulations identified optimal functionalization levels, balancing glycan-binding capability with solubility. From a biomaterials design perspective, we demonstrate how rational polymer modification can transform a potent but cytotoxic antimicrobial agent (i.e., PEI) into a safe and effective antibiofilm material, opening further possibilities for managing biofilm-associated infections in clinical settings. This work establishes boronic acid-based nanomaterials as promising candidates for biofilm prevention and antibiotic enhancement, particularly in conditions like cystic fibrosis, where mucin-bacterial interactions contribute to disease progression.}, }
@article {pmid40098712, year = {2025}, author = {Li, H and Zhang, S and Li, Q and Shu, Y and Li, S and Wu, B and Xu, Z}, title = {The Role of Yinqiao Powder in Modulating Pseudomonas aeruginosa Biofilm and Virulence Factors.}, journal = {Infection and drug resistance}, volume = {18}, number = {}, pages = {1405-1414}, pmid = {40098712}, issn = {1178-6973}, abstract = {PURPOSE: It is now understood that the primary challenges in treating Pseudomonas aeruginosa (P. aeruginosa) infections are the secretion of multiple virulence factors, the formation of biofilm, and the emergence of multi-drug resistance. Small regulatory RNAs (sRNAs) and quorum sensing (QS) play an important role in regulating bacterial biofilms and multiple virulence factors, presenting potential targets for novel anti-P. aeruginosa therapies. Yinqiao Powder has demonstrated inhibitory activity against various bacteria and viruses. The objective of this study was to elucidate the precise mechanism of Yinqiao Powder's impact on P. aeruginosa virulence and to ascertain its clinical utility.<br><br>METHODS: First, the effects of Yinqiao Powder on various virulence factors of P. aeruginosa were assessed through virulence phenotype experiments, including biofilm formation assay, pyocyanin production assay, rhamnolipid assay, and motility assay. Then, a cytotoxicity assay was used to evaluate the effect of P. aeruginosa treated by Yinqiao Powder on cells. Finally, an RT-qPCR assay was used to detect the effects of Yinqiao Powder on QS system and virulence-related gene expression.<br><br>RESULTS: This study revealed that sub-minimum inhibitory concentration (sub-MIC) levels of Yinqiao Powder significantly inhibit biofilm formation, swarming motility, pyocyanin and rhamnolipid production in a dose-dependent manner. The cytotoxicity assay also confirmed that Yinqiao Powder weakened the cytotoxicity of P. aeruginosa. Furthermore, Yinqiao Powder was found to modulate the P. aeruginosa sRNA-QS-virulence network. Specifically, it repressed the lasI, the rhlI, and sRNA P27 while upregulating sRNA PhrD. Additionally, the phzA and pqsA genes, associated with pyocyanin and rhamnolipid/biofilm regulation, respectively, were repressed by Yinqiao Powder.<br><br>CONCLUSION: Yinqiao Powder effectively inhibits QS system-related regulatory genes, sRNAs, biofilm formation, swarming motility, pyocyanin and rhamnolipid production at specific concentrations. These results support the potential of Yinqiao Powder as a quorum-sensing inhibitor.}, }
@article {pmid40098502, year = {2025}, author = {Yadav, P and Shyam Kumar Mishra,  and Shrestha, S and Sah, R and Rai, JR and Kattel, HP and Sharma, S and Willcox, M}, title = {Multidrug-Resistance and Biofilm Formation among Acinetobacter baumannii Isolated from Clinical Specimens.}, journal = {Journal of Nepal Health Research Council}, volume = {22}, number = {4}, pages = {662-669}, doi = {10.33314/jnhrc.v22i04.4694}, pmid = {40098502}, issn = {1999-6217}, mesh = {*Acinetobacter baumannii/drug effects/isolation &amp; purification ; *Biofilms/drug effects ; Cross-Sectional Studies ; Humans ; Nepal ; *Drug Resistance, Multiple, Bacterial ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; *Acinetobacter Infections/microbiology/drug therapy ; beta-Lactamases ; }, abstract = {BACKGROUND: Acinetobacter baumannii has emerged as a problematic pathogen due to its ability to become resistant to antibiotics and form biofilms. The aim of this study was to explore antibiotic resistance and biofilm formation, and examine any correlation between these in Acinetobacter baumannii isolates.<br><br>METHODS: This was a cross-sectional study conducted at the 750-bed Tribhuvan University Teaching Hospital in Nepal. Identification and antibiotic sensitivity of Acinetobacter baumannii isolates were performed following American Society for Microbiology guidelines. Different &#x3b2;-lactamases were detected by standard phenotypic tests. The microtiter plate method was used to screen strains of their ability to form biofilms.&#xa0; Results: Out of total 18,343 clinical samples processed, 4,249 (23.1%) showed bacterial growth. A. baumannii comprised of 4.7% of the total bacterial growth. Multidrug-resistant (MDR) was exhibited by 97.5% of Acinetobacter baumannii isolates. All multidrug-resistant Acinetobacter baumannii isolates were resistant to cephalosporins and carbapenems; however, they were sensitive to polymyxins. Only few isolates showed sensitivity to sulbactam-containing antibiotics (15.4-29.2%), fluoroquinolones (1.0-7.2%), aminoglycosides (2.6-5.6%), and cotrimoxazole (4.1%). Extended-spectrum-beta-lactamase (ESBL), metallo-beta-lactamase (MBL), Klebsiella pneumoniae carbapenemase (KPC) and AmpC production were found in 54.9%, 73.3%, 41.5% and 14.9% isolates, respectively. Among all tested isolates, 192 were able to produce biofilms, with 83.1% being classified as strong biofilm producers. Those strains that were resistant to gentamicin were more likely to produce biofilms (P<0.05). ESBL, MBL, KPC and AmpC were seen in 51.8%, 71.6%, 43.8% and 16.0% of strong biofilm producers respectively.<br><br>CONCLUSIONS: &#xa0; Only polymyxins were effective against Acinetobacter baumannii. Carbapenemase producers were generally strong biofilm producers, and gentamicin resistant strains were more likely to produce biofilms. The findings of this study may help to understand antibiotic-resistance mechanisms and provide valuable information in the treatment of MDR Acinetobacter baumannii infections.}, }
@article {pmid40098357, year = {2025}, author = {Chong, CSC and Lau, YY and Michels, PAM and Lim, CSY}, title = {Insights into biofilm-mediated mechanisms driving last-resort antibiotic resistance in clinical ESKAPE pathogens.}, journal = {Critical reviews in microbiology}, volume = {}, number = {}, pages = {1-26}, doi = {10.1080/1040841X.2025.2473332}, pmid = {40098357}, issn = {1549-7828}, abstract = {The rise of antibiotic-resistant bacteria poses a grave threat to global health, with the ESKAPE pathogens, which comprise Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp. being among the most notorious. The World Health Organization has reserved a group of last-resort antibiotics for treating multidrug-resistant bacterial infections, including those caused by ESKAPE pathogens. This situation calls for a comprehensive understanding of the resistance mechanisms as it threatens public health and hinder progress toward the Sustainable Development Goal (SDG) 3: Good Health and Well-being. The present article reviews resistance mechanisms, focusing on emerging resistance mutations in multidrug-resistant ESKAPE pathogens, particularly against last-resort antibiotics, and describes the role of biofilm formation in multidrug-resistant ESKAPE pathogens. It discusses the latest therapeutic advances, including the use of antimicrobial peptides and CRISPR-Cas systems, and the modulation of quorum sensing and iron homeostasis, which offer promising strategies for countering resistance. The integration of CRISPR-based tools and biofilm-targeted approaches provides a potential framework for managing ESKAPE infections. By highlighting the spread of current resistance mutations and biofilm-targeted approaches, the review aims to contribute significantly to advancing our understanding and strategies in combatting this pressing global health challenge.}, }
@article {pmid40097044, year = {2025}, author = {Lee, J and Shin, WR and Kim, YH and Ahn, JY and Chae, S and Min, J}, title = {Targeted Inhibition of Oral Biofilm Formation Using Phage-Derived High-Affinity Peptides.}, journal = {Journal of biotechnology}, volume = {}, number = {}, pages = {}, doi = {10.1016/j.jbiotec.2025.03.009}, pmid = {40097044}, issn = {1873-4863}, abstract = {Dental caries, commonly known as tooth decay, poses a significant oral health challenge affecting individuals of all age groups. While dietary factors play a role, tooth decay primarily results from the activity of various oral bacteria that form biofilms in the oral cavity. In this study, we employed the phage display technique to identify high-affinity peptides capable of binding specifically to three oral bacteria strains: Streptococcus mutans, Streptococcus oralis, and Lactobacillus casei. Four selected peptides underwent binding affinity testing for each target bacterium, revealing that three of them exhibited specific binding capabilities, effectively inhibiting biofilm formation. This study demonstrates the efficacy of engineered phages in identifying high-affinity peptides that selectively target oral bacteria. These peptides hold promise for preventing oral biofilm formation, a significant contributor to oral diseases and dental caries. This innovative approach opens doors to novel therapeutic strategies for addressing oral health issues. The findings may spur further research into the utilization of phages and peptides as potential anti-biofilm agents, potentially revolutionizing the field of oral health.}, }
@article {pmid40096907, year = {2025}, author = {Leite de Oliveira Rosa, I and de O Ferreira, E and Vieira Colombo, AP}, title = {Molecular detection of toxigenic Clostridioides difficile in subgingival biofilm of severe periodontitis.}, journal = {Anaerobe}, volume = {}, number = {}, pages = {102955}, doi = {10.1016/j.anaerobe.2025.102955}, pmid = {40096907}, issn = {1095-8274}, abstract = {OBJECTIVES: The oral cavity is the main gateway for the entry of C. difficile spores to the digestive tract. In conditions of poor oral hygiene and periodontal diseases, the dysbiotic oral microbiota may be a reservoir for several human pathogens. Here, we explored the prevalence of C. difficile in the oral microbiota of patients with severe periodontitis by the molecular detection of species specific genes.<br><br>METHODS: Subgingival biofilm, saliva and/or feces from 659 patients with gingivitis, periodontitis and no periodontal diseases were screened for the tpi and toxin A/B genes specific for C. difficile by multiplex PCR. Differences among groups were sought by the Chi-square test.<br><br>RESULTS: The overall frequency of C. difficile tpi gene was 29%, with a high detection of tcdB gene (44.8%). Patients with periodontitis showed a greater prevalence of this gene in the biofilm than individuals with gingivitis and periodontal health (p=0.001), particularly at more severe stages of disease (p<0.05). No toxin genes were detected in feces or biofilm from healthy patients, whereas >70% of the biofilm from patients with periodontal diseases were positive for these genes (p<0.001). Detection of C. difficile tpi gene in oral/fecal samples correlated with periodontal inflammation (p<0.05). A modest intra-individual agreement between tpi gene detection in feces and saliva was found within periodontitis patients (Kappa=0.314; p=0.003).<br><br>CONCLUSION: The high frequency of the C. difficile specific genes tpi and tcdB in the dysbiotic subgingival biofilm of advanced periodontitis could support the presence of this species in this niche.}, }
@article {pmid40096867, year = {2025}, author = {Ma, Z and Zhang, Z and Fu, S and Jiang, L and Sun, Y and Zhu, Y and Wang, Y and Cheng, W and Ma, X and Liang, H and Tang, X}, title = {Integration of moving bed biofilm reactor and gravity-driven membrane bioreactor for decentralized domestic wastewater treatment: Efficiency and mechanistic insights.}, journal = {Bioresource technology}, volume = {}, number = {}, pages = {132399}, doi = {10.1016/j.biortech.2025.132399}, pmid = {40096867}, issn = {1873-2976}, abstract = {This study investigated the coupling of a moving bed biofilm reactor (MBBR) with a gravity-driven membrane bioreactor (GDMBR) for the long-term treatment of decentralized domestic wastewater. The results indicated that the introduction of MBBR significantly improved the stable flux of GDMBR (by 8 %-22 %) and enhanced its resistance to the shock loading of influent quality. Such improvements were attributed to the reduction in extracellular polymeric substances (EPS) (by 30 %-46 %), positive modifications to the membrane biofilm, and improvements in microbial richness and community composition. Compared to GDMBR control, the start-up period of MBBR-GDMBR systems was reduced by 6-15 days, owing to the beneficial effects of MBBR-derived microorganisms, which promoted microbial evolution within the GDMBR membrane biofilm, thereby accelerating the stabilization of filtration performance. Overall, this study provides valuable insights into shortening the start-up period of the GDMBR process, enhancing its resistance to external shock loads, and improving flux levels.}, }
@article {pmid40096799, year = {2025}, author = {Wan, L and Kimball, K and Cusick, A and Morocco, F}, title = {Achromobacter xylosoxidans: An uncommon scalp infection leading to alopecia and biofilm formation.}, journal = {Diagnostic microbiology and infectious disease}, volume = {112}, number = {2}, pages = {116797}, doi = {10.1016/j.diagmicrobio.2025.116797}, pmid = {40096799}, issn = {1879-0070}, abstract = {Achromobacter xylosoxidans is an emerging opportunistic pathogen causing respiratory and systemic infections, mainly in immunocompromised individuals. Cutaneous infections remain uncommon. We present a unique case of a 60-year-old immunocompetent female with a persistent, pruritic, and malodorous scalp infection for over a year, leading to alopecia and biofilm formation, complicating treatment by increasing antibiotic resistance. Despite lacking typical risk factors, wound culture identified A. xylosoxidans with susceptibility to trimethoprim-sulfamethoxazole, which led to successful treatment alongside surgical debridement. This case highlights the need for clinicians to consider A. xylosoxidans in differential diagnoses of unusual skin infections, especially when biofilm formation is evident, and underscores the importance of targeted antibiotic therapy due to this pathogen's multidrug resistance.}, }
@article {pmid40095793, year = {2025}, author = {Moon, Y and Hong, J and Choi, S and Kim, H and Sohn, HM and Jo, S}, title = {Biofilm Growth on Different Materials Used in Contemporary Femoral Head Prosthesis: An In Vitro Study.}, journal = {Journal of clinical medicine}, volume = {14}, number = {5}, pages = {}, doi = {10.3390/jcm14051722}, pmid = {40095793}, issn = {2077-0383}, support = {RS-2023-00217471//National Research Foundation of Korea/ ; }, abstract = {Background/Objectives: Periprosthetic joint infection (PJI) primarily results from bacterial biofilms adhering to prosthetic surfaces, making treatment challenging without prosthesis removal. This in vitro study aims to investigate whether the materials used in contemporary femoral head prosthesis influences bacterial biofilm development. Methods: Femoral head prostheses made of three different materials-cobalt-chrome, oxinium, and ceramic-were inoculated with either Staphylococcus aureus or Pseudomonas aeruginosa in separate experiments, with each pathogen tested independently. The samples were cultured under shaking conditions at 37 °C for 96 h to promote biofilm formation. Scanning electron microscopy (SEM) was used to confirm the presence of biofilms, and adherent biofilms were quantified by counting colony-forming units (CFUs) after sonication. Additionally, crystal violet staining was performed to assess biofilm distribution on the femoral head surfaces. Statistical analyses compared CFU counts across the different materials. Results: The mean CFU counts for S. aureus were 7.6 × 10[5] ± 9.7 × 10[4] for cobalt-chrome, 6.9 × 10[5] ± 3.6 × 10[5] for oxinium, and 1.1 × 10[6] ± 3.0 × 10[5] for ceramic femoral head prostheses. For P. aeruginosa, the CFU counts were 2.3 × 10[6] ± 7.2 × 10[5], 3.7 × 10[6] ± 2.5 × 10[6], and 2.2 × 10[6] ± 8.9 × 10[5], respectively. Regardless of the bacterial strain, differences among the three materials were within one log range, and no statistical significance was observed. While biofilms were confirmed using SEM, limited adherence was observed on the bearing surface, with the biofilm predominantly localized in the taper hole. Conclusions: The findings suggest that the material used in contemporary femoral head prostheses has minimal impact on bacterial biofilm formation. Surgeons' choice of femoral head prosthesis material should base their material selection on factors other than PJI prevention.}, }
@article {pmid40094363, year = {2025}, author = {de Castro, PA and Akiyama, DY and Pinzan, CF and Dos Reis, TF and Delbaje, E and Rocha, P and Izidoro, MA and Schenkman, S and Sugimoto, S and Takeshita, N and Steffen, K and Aycock, JL and Dolan, SK and Rokas, A and Fill, T and Goldman, GH}, title = {Aspergillus fumigatus secondary metabolite pyripyropene is important for the dual biofilm formation with Pseudomonas aeruginosa.}, journal = {mBio}, volume = {}, number = {}, pages = {e0036325}, doi = {10.1128/mbio.00363-25}, pmid = {40094363}, issn = {2150-7511}, abstract = {The human pathogenic fungus Aspergillus fumigatus establishes dual biofilm interactions in the lungs with the pathogenic bacterium Pseudomonas aeruginosa. Screening of 21 A. fumigatus null mutants revealed seven mutants (two G protein-coupled receptors, three mitogen-activated protein kinase receptors, a Gα protein, and one histidine kinase receptor) with reduced biofilm formation, specifically in the presence of P. aeruginosa. Transcriptional profiling and metabolomics analysis of secondary metabolites produced by one of these mutants, ΔgpaB (gpaB encodes a Gα protein), showed GpaB controls the production of several important metabolites for the dual biofilm interaction, including pyripyropene A, a potent inhibitor of mammalian acyl-CoA cholesterol acyltransferase. Deletion of pyr2, encoding a non-reducing polyketide synthase essential for pyripyropene biosynthesis, showed reduced A. fumigatus Δpyr2-P. aeruginosa biofilm growth, altered macrophage responses, and attenuated mouse virulence in a chemotherapeutic murine model. We identified pyripyropene as a novel player in the ecology and pathogenic interactions of this important human fungal pathogen.IMPORTANCEAspergillus fumigatus and Pseudomonas aeruginosa are two important human pathogens. Both organisms establish biofilm interactions in patients affected with chronic lung pulmonary infections, such as cystic fibrosis (CF) and chronic obstructive pulmonary disease. Colonization with A. fumigatus is associated with an increased risk of P. aeruginosa colonization in CF patients, and disease prognosis is poor when both pathogens are present. Here, we identified A. fumigatus genetic determinants important for the establishment of in vitro dual A. fumigatus-P. aeruginosa biofilm interactions. Among them, an A. fumigatus Gα protein GpaB is important for this interaction controlling the production of the secondary metabolite pyripyropene. We demonstrate that the lack of pyripyropene production decreases the dual biofilm interaction between the two species as well as the virulence of A. fumigatus in a chemotherapeutic murine model of aspergillosis. These results reveal a complete novel role for this secondary metabolite in the ecology and pathogenic interactions of this important human fungal pathogen.}, }
@article {pmid40093894, year = {2025}, author = {Deng, Y and Zheng, J and Li, J and Liu, B and Chen, K and Xu, Y and Deng, L and Liu, H and Liu, YN}, title = {NIR light-driven nanomotor with cascade photodynamic therapy for MRSA biofilm eradication and diabetic wound healing.}, journal = {Theranostics}, volume = {15}, number = {8}, pages = {3474-3489}, pmid = {40093894}, issn = {1838-7640}, mesh = {*Methicillin-Resistant Staphylococcus aureus/drug effects ; *Biofilms/drug effects ; Animals ; *Wound Healing/drug effects ; *Photochemotherapy/methods ; Mice ; *Anti-Bacterial Agents/pharmacology ; *Indocyanine Green/pharmacology/administration &amp; dosage ; *Staphylococcal Infections/drug therapy/therapy ; *Nanoparticles/chemistry ; Infrared Rays ; Photosensitizing Agents/pharmacology ; Diabetes Mellitus, Experimental/complications ; Humans ; }, abstract = {Background: Diabetic wounds infected with methicillin-resistant Staphylococcus aureus (MRSA) are challenging to heal due to biofilm formation, which impairs conventional antibiotics with limited penetration and severe side effects. Near-infrared (NIR)-driven nanomotors with autonomous motion and photothermal effects show promise for antibacterial therapy but often lack targeted specificity. Lysostaphin (Ly), an enzyme targeting bacterial cell walls, offers excellent potential against drug-resistant MRSA. Methods: A novel NIR-driven CSIL nanomotor has fabricated by co-loading indocyanine green (ICG) and lysostaphin onto spinous yolk-shell structured C/SiO2@C nanoparticles. The autonomous motion, biofilm penetration, and antibacterial efficacy of CSIL nanomotors are evaluated in vitro, while their biofilm eradication and wound healing performance are assessed in an MRSA-infected diabetic mouse model using a cascade photodynamic therapy (CPDT) strategy. Results: CSIL nanomotors exhibit photothermal and photodynamic properties with MRSA-targeting specificity. They can effectively eradicate MRSA biofilms both in vitro and in vivo, suppress virulence and biofilm-related genes, thus promoting diabetic wound healing by shaping a microenvironment dominated by M2 macrophages. The CPDT strategy is able to avoid excessive ROS production and thermal damage, enabling safe and effective therapy. Conclusion: CSIL nanomotors, with integrated photothermal, photodynamic, and MRSA-targeting properties, represent a novel, efficient and targeted approach to antibacterial therapy in diabetic wounds, offering significant advantages over conventional antibiotics.}, }
@article {pmid40093892, year = {2025}, author = {Han, Z and Li, Y and Zhan, X and Sun, M and Liang, Y and Yuan, M and Sun, Y and Cao, J and Zhao, B and Li, F}, title = {A versatile nanoplatform with excellent biofilm permeability and spatiotemporal ROS regulation for peri-implantitis treatment.}, journal = {Theranostics}, volume = {15}, number = {8}, pages = {3490-3516}, pmid = {40093892}, issn = {1838-7640}, mesh = {*Peri-Implantitis/drug therapy/therapy ; *Biofilms/drug effects ; *Reactive Oxygen Species/metabolism ; Animals ; *Photochemotherapy/methods ; *Anti-Bacterial Agents/pharmacology ; Mice ; Photosensitizing Agents/pharmacology ; Nanoparticles/chemistry ; Permeability/drug effects ; Male ; RAW 264.7 Cells ; Rats ; Dental Implants/microbiology ; Humans ; Anti-Inflammatory Agents/pharmacology ; }, abstract = {Rationale: Dental implant restoration is essential for rehabilitating dentition defects. However, peri-implantitis (PI) seriously threatens the long-term stability of implants. Treating PI requires the complete eradication of plaque biofilm and the meticulous modulation of inflammatory responses. Antibacterial photodynamic therapy (aPDT) presents a promising potential in the antibacterial realm. Nonetheless, traditional aPDT for PI faces challenges such as inadequate biofilm penetration and distribution of photosensitizers, as well as a lack of precise bacteria targeting. Moreover, the excessive ROS generated by aPDT will aggravate the oxidative stress of peri-implant tissues, and this issue cannot be neglected. Methods: The CuTA-Por@ε-PL nanoplatforms (CPP NPs) were synthesized and characterized using dynamic light scattering, transmission electron microscopy, and dye probes in detail. The antibacterial and anti-inflammatory activities of CPP NPs were evaluated both in vitro and in vivo. Moreover, the in vivo therapeutic efficacy was successively analyzed through micro-CT, hematoxylin and eosin staining, Masson's staining, immunofluorescence staining, and colony formation units (CFU), among other techniques. Results: Porphyrin (Por), CuTA nanozyme with SOD/CAT activities, and ε-Polylysine (ε-PL) were combined to fabricate CPP NPs via a straightforward approach. The notable positive charge of CPP NPs facilitated biofilm penetration, distribution and precise bacteria targeting. Then, irradiation with a 660 nm laser triggered a ROS burst for biofilm elimination. After aPDT, CPP NPs scavenged the residual ROS and modulated host immunity by regulating macrophage polarization. As a result, CPP-treated groups demonstrated the most outstanding antibacterial and anti-inflammatory performance in the rat PI model. Conclusions: Given the pathogenesis of PI, this strategy rationally designed a multifunctional NP with antibacterial and anti-inflammatory functions via spatiotemporal ROS regulation. It provides a potentially novel approach for PI treatment, which may have a profound impact on improving the prognosis of patients with PI and advancing the field of implant dentistry.}, }
@article {pmid40093652, year = {2025}, author = {Van Roy, Z and Kielian, T}, title = {Immune-based strategies for the treatment of biofilm infections.}, journal = {Biofilm}, volume = {9}, number = {}, pages = {100264}, pmid = {40093652}, issn = {2590-2075}, abstract = {Biofilms are bacterial communities surrounded by a polymeric matrix that can form on implanted materials and biotic surfaces, resulting in chronic infection that is recalcitrant to immune- and antibiotic-mediated clearance. Therefore, biofilm infections present a substantial clinical challenge, as treatment often involves additional surgical interventions to remove the biofilm nidus, prolonged antimicrobial therapy to clear residual bacteria, and considerable risk of treatment failure or infection recurrence. These factors, combined with progressive increases in antimicrobial resistance, highlight the need for alternative therapeutic strategies to circumvent undue morbidity, mortality, and resource strain on the healthcare system resulting from biofilm infections. One promising option is reprogramming dysfunctional immune responses elicited by biofilm. Here, we review the literature describing immune responses to biofilm infection with a focus on targets or strategies ripe for clinical translation. This represents a complex and dynamic challenge, with context-dependent host-pathogen interactions that differ across infection models, microenvironments, and individuals. Nevertheless, consistencies among these variables exist, which could facilitate the development of immune-based strategies for the future treatment of biofilm infections.}, }
@article {pmid40093626, year = {2025}, author = {Baek, J and Lee, J and Jeong, YJ and Oh, SY and Kang, SS}, title = {Inhibition of Salmonella Typhimurium Biofilm Formation, Adhesion, and Invasion by Whey Beverage Supplemented with Triticum dicoccum (Farro) Enzyme.}, journal = {Food science of animal resources}, volume = {45}, number = {2}, pages = {648-661}, pmid = {40093626}, issn = {2636-0780}, abstract = {Triticum dicoccum (Farro) an ancient wheat species has recently gained attention for its exceptional health benefits. However, research on its antibacterial and anti-biofilm properties remains limited. Additionally, a growing trend has been observed in releasing enriched or fortified whey beverages to enhance their functionality. Therefore, this study aimed to investigate the inhibitory effects of whey beverages supplemented with enzyme-rich fermented farro (WF) on Salmonella Typhimurium biofilm formation and explore the underlying mechanisms. Treatment with WF significantly reduced biofilm formation and viability of S. Typhimurium. Moreover, WF decreased the bacterial adhesion to and invasion of human intestinal epithelial cells. WF also inhibited gene expression associated with motility and initial adhesion in S. Typhimurium, as well as genes involved in quorum sensing (QS), in a concentration-dependent manner. Furthermore, WF suppressed the production of the QS signaling molecule autoinducer-2 in a similar concentration-dependent manner. Consequently, our findings indicate that the addition of enzyme-rich fermented farro to whey beverage enhances anti-biofilm activity, which is probably attributed to its antimicrobial effects, inhibition of initial adhesion, and QS reduction. These findings offer a promising basis for developing fortified dairy beverages that can enhance food safety and promote human health.}, }
@article {pmid40092801, year = {2025}, author = {Islam, MH and Hosna Ara, M and Khan, MA and Naime, J and Khan, MAR and Rahman, ML and Ruhane, TA}, title = {Preparation of Cellulose Nanocrystals Biofilm from Coconut Coir as an Alternative Source of Food Packaging Material.}, journal = {ACS omega}, volume = {10}, number = {9}, pages = {8960-8970}, pmid = {40092801}, issn = {2470-1343}, abstract = {The current perspective emphasizes on the synthesis of a biofilm from cellulose nanocrystals (CNC) of coconut coir for the development of sustainable packaging materials as an alternative source of plastic. The biofilm was prepared by a solvent-casting method and investigated by various analytical techniques. Of them, surface morphology was observed by SEM, suggesting a crystalline rod shape with particle size of 104-318 nm and diameter of 15-70 nm. However, CNC was incorporated with starch at various ratios ranging from 10:0 to 1:9; the ratio 6:4 of CNC and the binder maximized the mechanical properties of the polymer. In the presence of a plasticizer and a cross-linker, the film possessed high tensile strength (38.4 ± 1.57 MPa) and elongation (8.2 ± 0.39%) compared to commercially available polyethylene (9.84 ± 0.32 MPa and 23 ± 0.74%). The biofilm possessed a great extent of cross-link structure, divulging through the change of contact angle (92°), surface morphology (rough surface), crystallinity (45.36%), water vapor transmission rate (427 g/m[2]/day), and thermal stability from 232 to 258 °C. The degree of deterioration was assessed by the soil burial test (30-45 days), highlighting the environmental compatibility of the film.}, }
@article {pmid40092759, year = {2025}, author = {Alves, GB and Calderari, MRDCM and Fonseca, END and Sant'anna, LO and Santos, LSD and Mattos-Guaraldi, AL}, title = {Photodynamic Inactivation Mediated by Endogenous Porphyrins of Corynebacterium diphtheriae in Planktonic and Biofilm Forms.}, journal = {ACS omega}, volume = {10}, number = {9}, pages = {9177-9186}, pmid = {40092759}, issn = {2470-1343}, abstract = {Photodynamic inactivation (PDI) has emerged as a promising approach to combat bacterial infections by using light activation of photosensitizers to induce microbial death. This study investigated the potential of endogenous porphyrins produced by Corynebacterium diphtheriae as photosensitizers for PDI. Qualitative analysis revealed the presence of porphyrins in all strains studied, with coproporphyrin III predominating. The addition of 5-aminolevulinic acid (ALA) enhanced porphyrin production, as evidenced by increased fluorescence intensity. In addition, high-performance liquid chromatography with diode array and mass spectrometry detection analyses confirmed the presence of coproporphyrin III and protoporphyrin IX in all strains, and the ALA supplementation did not alter the porphyrin profiles. Quantitative analysis showed that strain-dependent coproporphyrin III levels were significantly increased with ALA supplementation. Additionally, biofilm formation was positively correlated with porphyrin production, suggesting a role for porphyrins in biofilm formation. Photoinactivation experiments showed that the strains responded differently to light exposure, with ALA supplementation, reducing the time required for significant CFU/mL reduction. In addition, biofilm survival exceeded planktonic cell survival, highlighting the challenges posed by biofilm structures with regard to PDI efficacy. Despite the variable responses observed, all strains exhibited a reduction in viability following light exposure, demonstrating the potential of endogenous porphyrins for antimicrobial photoinactivation applications.}, }
@article {pmid40090255, year = {2025}, author = {Dong, J and Zhang, S and Chan, YK and Lai, S and Deng, Y}, title = {Vacancies-rich Z-scheme VdW heterojunction as H2S-sensitized synergistic therapeutic nanoplatform against refractory biofilm infections.}, journal = {Biomaterials}, volume = {320}, number = {}, pages = {123258}, doi = {10.1016/j.biomaterials.2025.123258}, pmid = {40090255}, issn = {1878-5905}, abstract = {Encapsulated in a self-produced negatively charged extracellular polymeric substance (EPS) matrix, the wound infected bacterial biofilms exhibit formidable resistance to conventional positively charged antibiotics and host's immune responses, which can undoubtedly lead to persistent infections and lethal complications. Nevertheless, developing efficacious strategies to root out stubborn biofilm and promote tissue regeneration still remains a challenge. To resolve this dilemma, a versatile vacancies-rich Z-scheme MoSSe Van der Waals heterojunction (MoSSe VdW HJ) is rationally fabricated as nanoplatform for hydrogen sulfide (H2S)-sensitized synergistic therapy of wound bacterial biofilm infection. The rich anion vacancies and Z-scheme heterostructure make the fabricated MoSSe VdW HJ can effectively augment H2S, localized hyperthermia, and reactive oxygen species production under the stimulation of biofilm microenvironments (BME) and irradiation of 808 nm near-infrared (NIR) light. Therefore, MoSSe VdW HJ is capable to integrate H2S gas, chemodynamic, photothermal, and photodynamic therapies to effectively destroy eDNA and polysaccharides in the EPS matrix, thereby breaching the biofilm barrier to eradicate bacteria and facilitate wound healing. The synergistic strategy exhibits superior anti-biofilm and wound repair effects both in vivo and in vitro, thus providing guideline for the development of BME and NIR light activated synergistic therapeutics to fight against refractory biofilm infections.}, }
@article {pmid40090148, year = {2025}, author = {Dong, KY and Yang, CX and Pang, JL and Chang, RR and Chen, KY and Yao, W and Huang, BC and Jin, RC}, title = {Antibiotics shape the core microbial community distribution between floc and biofilm in an endogenous partial denitrification system: Insight from metabolic pathway.}, journal = {Water research}, volume = {280}, number = {}, pages = {123491}, doi = {10.1016/j.watres.2025.123491}, pmid = {40090148}, issn = {1879-2448}, abstract = {The response mechanism of microorganisms in partial denitrification (PD) system under antibiotic stress, particularly microbial energy metabolism and electron transfer, remain inadequately understood. This knowledge gap hinders the establishment of ecological links between microbial dynamics and macro-level reactor performance. To address this, moving bed biofilm reactors were employed to investigate the dynamic changes of microbial community and metabolism under sulfadiazine (SDZ) and ciprofloxacin (CIP) stress. Results showed that dosing 2 mg/L SDZ or CIP accelerated nitrite accumulation, achieving this milestone 15 days earlier than in the control group. At the end of the operational phase, nitrate removal efficiencies reached 90.3 ± 18.3 % (Control), 83.5 ± 16.2 % (SDZ-treated) and 93.9 ± 12.4 % (CIP-treated), with nitrate-to nitrite-transformation rates of 61.3 ± 12.7 %, 65.6 ± 13.1 % and 58.0 ± 21.2 %, respectively. The abundances of energy supply related genes, i.e., sucC and PK were higher in the CIP-treated group, while those in the other two groups were similar. The promoted tricarboxylic acid cycle and glycolysis led to NADH and ATP accumulation, accelerating nitrogen metabolism and benefiting early nitrite accumulation in the antibiotic-stressed system. More importantly, increasing antibiotics concentration from 2 mg/L to 4 mg/L induced selective migration of Thauera from floc to biofilm (abundance in floc reduced to < 2.01 %). Metagenomic sequencing indicated that the higher abundance of narGHI in biofilms, compared to flocs, was crucial for maintaining stable PD performance under antibiotic stress. The electron transport related genes, such as IDH1, DLD and DLAT, were more abundant in biofilms than in flocs after SDZ and CIP addition. These findings provide a theoretical basis for understanding the response mechanism of PD consortia to antibiotic.}, }
@article {pmid40090043, year = {2025}, author = {Marín, A and Feijóo, P and Carbonetto, B and González-Torres, P and Tena-Medialdea, J and García-March, JR and Gámez-Pérez, J and Cabedo, L}, title = {Long-term monitoring of biofilm succession unveils differences between biodegradable and conventional plastic materials.}, journal = {Marine pollution bulletin}, volume = {214}, number = {}, pages = {117820}, doi = {10.1016/j.marpolbul.2025.117820}, pmid = {40090043}, issn = {1879-3363}, abstract = {A vast amount of plastic waste enters the ocean every year and the Mediterranean Sea is particularly affected by this issue. Biodegradable polymers like poly(lactic acid) (PLA) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), may help mitigate this problem. We investigated bacterial biofilm development and succession on these polymers over one year in the Western Mediterranean Sea. Scanning electron microscopy (SEM) and confocal laser scanning were used to examine microbial colonization and surface erosion, while bacterial community abundance and composition were assessed through culture plate counting and 16S rRNA gene amplicon sequencing. SEM revealed significant surface erosion on PHBV, indicative of microbial degradation, while PLA exhibited minor and irregular erosion. Culture-based quantification showed higher bacterial colonization on PHBV compared to PLA, suggesting that PHBV provides a more favourable surface for bacterial attachment Amplicon sequencing of the 16S rRNA gene revealed high bacterial diversity, with 17,781 operational taxonomic units across all samples. Proteobacteria, Bacteroidota, and Planctomycetota were the dominant phyla, with the Shannon index consistently exceeding 8, corroborating the bacterial diversity across all materials. Temporal shifts in bacterial community composition were significant, with exposure time explaining 29.8 % of the variation, suggesting biofilm succession as a key factor shaping microbial assemblages. While polymer type had a limited impact on bacterial composition, PHBV biofilms exhibited greater bacterial abundance and diversity compared to PLA. This study highlights PHBV's role in shaping biofilms and its relevance in assessing biodegradable plastics in marine environments. Understanding microbial interactions with bioplastics is crucial for evaluating their environmental impact and degradation dynamics.}, }
@article {pmid40089195, year = {2025}, author = {Senthil Kumar, SA and Praveenkumar, K and Jothipandian, S and Swaroop, S and Nithyanand, P}, title = {Nanoscale Surface Modifications on Titanium Plates- A Strategy to Mitigate MRSA Biofilm-mediated Implant Infections: a pilot Study.}, journal = {Microbial pathogenesis}, volume = {}, number = {}, pages = {107481}, doi = {10.1016/j.micpath.2025.107481}, pmid = {40089195}, issn = {1096-1208}, abstract = {Orthopaedic implant infections pose a major threat after implantation. Biofilms of pathogenic bacteria resistant to antibiotics cause biomaterial infections. Methicillin-resistant Staphylococcus aureus (MRSA) is one of the prevalent biofilm-forming pathogens associated with implant infection in high proportion. Loss of effectiveness of antibiotics against these drug-resistant pathogens demands alternative approaches to surmount this crisis. Various strategies involving antibiotics, biocides, and metal ions are employed as the prohibiting steps of biofilm formation. Hence, to prevent biofilm formation and infections caused by biofilms formed over the orthopaedic implants, we involved laser micro-machining to modify the surface of the Titanium (Ti) plate, the most widely used implant material. Interestingly, we found that the laser-peening process generated widespread nanosized pores and micro-roughness to the surface of the Ti plate. Laser-peened Ti plate reduced the adhesion of MRSA over the metal surface and also retained its capacity to inhibit biofilm formation, which was confirmed with scanning electron microscopy (SEM). The biofilm assays like quantification of biofilm by crystal violet, determination of colony forming unit from biofilm formed over the control and laser-peened Ti plates showed that the laser-peened Ti plate significantly reduced the adherence of biofilm-forming MRSA. Moreover, the genes responsible for biofilm adhesion were found to be downregulated which was confirmed by qPCR. From our results, it was found that laser-peened Ti implants would be an alternative strategy to prevent biofilm-mediated infection on orthopaedic implant material.}, }
@article {pmid40086759, year = {2025}, author = {Wu, T and Zhao, P and Pan, P and Zhao, Z and Zhu, Y and Cheng, J}, title = {Biofilm-disrupting DNA nanomedicines for targeted elimination of resistant wound microbiota.}, journal = {Journal of controlled release : official journal of the Controlled Release Society}, volume = {}, number = {}, pages = {113618}, doi = {10.1016/j.jconrel.2025.113618}, pmid = {40086759}, issn = {1873-4995}, abstract = {Biofilms are complex bacterial communities that significantly hinder the treatment of chronic and recurrent infections by enhancing bacterial virulence and conferring resistance to antimicrobial therapies. To address this challenge, an intelligent DNA nanomedicine has been engineered to dismantle biofilms and target resistant bacteria, offering an innovative solution for chronic wound infections. These nanomedicines initiate biofilm degradation through in situ generation of potent oxidative radicals, enabling deep biofilm penetration and precise bacterial targeting. Utilizing aptamers for specific bacterial identification, the nanomedicines concentrate therapeutic agents directly at infection sites. The combined effect of severe oxidative stress and sustained silver ion release ensures a continuous, focused assault on pathogens, effectively eradicating resistant bacteria. This strategy demonstrated broad-spectrum efficacy against both Gram-positive and Gram-negative bacteria, significantly enhancing wound healing in a diabetic infection model. By integrating intelligent bacterial eradication with modulation of the wound microenvironment, this approach presents a promising solution for overcoming biofilm-associated resistance and advancing chronic wound infection treatment.}, }
@article {pmid40084081, year = {2025}, author = {Nirmala, B and Omar, BJ}, title = {Microbial Biofilm Detection and Differentiation by Dual Staining Using Maneval's Stain.}, journal = {Bio-protocol}, volume = {15}, number = {5}, pages = {e5228}, pmid = {40084081}, issn = {2331-8325}, abstract = {Microbial biofilms are structured communities of microorganisms embedded in a self-produced extracellular matrix, adhering to surfaces. These biofilms enhance bacterial resistance to antibiotics, immune responses, and environmental stress. Current microscopy techniques, such as scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), and fluorescence microscopy, are commonly used to visualize and differentiate biofilms. However, their high cost and complexity often render them impractical. In contrast, simpler methods like crystal violet and Congo red staining are limited in distinguishing bacterial cells from the biofilm matrix. This study introduces a cost-effective, dual-staining method using Maneval's stain to visualize and differentiate microbial biofilms. It requires only basic equipment and minimal reagents, making it ideal for routine use in clinical diagnosis and microbial research. Key features • This dual-staining method differentiates bacterial cells, biofilm matrix, and capsules in a single stain. • This method applies to both bacterial and fungal biofilm. • This method requires no specialized training or equipment, with the entire process completed within 30-45 min. • Stained slides can be stored for extended periods (months) without degradation.}, }
@article {pmid40083859, year = {2025}, author = {Ketteler, HM and Johnson, EL and McGlennen, M and Dieser, M and Foreman, CM and Warnat, S}, title = {A simulated microgravity biofilm reactor with integrated microfabricated sensors: Advancing biofilm studies in near-space conditions.}, journal = {Biofilm}, volume = {9}, number = {}, pages = {100263}, pmid = {40083859}, issn = {2590-2075}, abstract = {Studying biofilms in a microgravity environment currently relies on one of two scenarios, collecting planktonic aggregates in rotating wall vessels or performing experiments in the microgravity environment of space on the International Space Station. While informative techniques, both have their limitations when studying surface-attached microbial communities. A simulated microgravity biofilm reactor (SMBR) was developed to study biofilms in microgravity, coupled with the integration of microfabricated sensors for internal system monitoring. The establishment of simulated microgravity was demonstrated through computational fluid dynamic modelling revealing low fluid shear stress conditions (<1 mPa) throughout the reactor and on the wall surface. Microfabricated resistance temperature devices integrated in the reactor walls confirmed the capability for continuous sensor measurements during operation with the ability to perform traditional microbiology analyses on the sensor surface following an experiment. Microbiological analyses established that there were no significant differences in biofilm growth between sensor and wall surfaces within the reactor. With the integration of defined sampling surfaces, the SMBR allows for in-depth biofilm analysis in a repeatable and accessible manner allowing for a greater understanding of the effects of microgravity on biofilm.}, }
@article {pmid40081688, year = {2025}, author = {Yang, T and Li, H and Yu, R and Yu, X and Li, Y and Duan, Z and Yang, J and Tao, G and Huang, A and Shi, Y}, title = {Lactoferrin-alginate-pectin composite hydrogel: Enhancing Lactobacillus plantarum B072 survival, density and biofilm formation.}, journal = {International journal of biological macromolecules}, volume = {}, number = {}, pages = {141983}, doi = {10.1016/j.ijbiomac.2025.141983}, pmid = {40081688}, issn = {1879-0003}, abstract = {This research established a novel ternary composite hydrogel matrix composed of lactoferrin (Lf), sodium alginate (SA), and high ester pectin (HEP) for encapsulation Lactobacillus plantarum B072. The synergy of these components creates a robust, stable, and protective environment for the encapsulation of L. plantarum B072. The hydrogel beads exhibited high a encapsulation efficiency of 76.43 %, excellent mechanical strength, and thermal stability, while promoting biofilm formation, significantly increasing bacterial density to 9.57 log CFU/mL, and enhancing acid resistance, thereby providing an effective physical barrier against gastrointestinal stress. Hydrogen bonds and electrostatic repulsion play a critical role in maintaining the compact structure of the hydrogel, while hydrogen bonds and hydrophobic interactions further enhance its structural stability. Molecular docking analysis demonstrated that LF-casein forms stable complexes with HEP by binding to specific active sites, including LEU-708, GLY-342, ARG-268, LEU-266, ARG-361, ASN-349, LEU-404, MET-622, and PRO-153. In simulated gastrointestinal digestion, the encapsulated L. plantarum B072 achieved a survival of 7.42 log CFU/mL, outperforming free bacteria. This work provides a new strategy for the development of probiotic delivery systems and the improvement of product stability.}, }
@article {pmid40081052, year = {2025}, author = {Zhang, Y and Ren, M and Su, J and Bai, Y and Li, X and Wang, Y}, title = {Simultaneous removal of carbamazepine, nitrate, and copper in a biofilm reactor filled with FeMn-modified ceramsite.}, journal = {Journal of hazardous materials}, volume = {491}, number = {}, pages = {137871}, doi = {10.1016/j.jhazmat.2025.137871}, pmid = {40081052}, issn = {1873-3336}, abstract = {Mixtures of pollutants are a significant challenge for conventional wastewater treatment processes. In the present work, the potential of a biofilm reactor to simultaneously remove nitrate (NO3[-]-N), carbamazepine (CBZ), and copper ions (Cu[2+]) was evaluated. The reactor was filled with FeMn-modified ceramsite (CS@FeMn) and inoculated with the strains of Cupriavidus sp. HY129 and Pantoea sp. MFG10, which contributed to the redox cycling of Mn. Under optimum conditions with the HRT, C/N and pH of 9.0 h, 2.0, and 7.0, respectively, the bioreactor incorporating CS@FeMn demonstrated a significant increase in nitrogen removal capacity compared to the CS carrier, achieving a NRE of 96.7 %. Moreover, the removal efficiencies of CBZ and Cu[2+] reached the values of 91.8 % and 85.6 %, respectively. The experimental results indicated that the removals of CBZ and Cu[2+] were closely associated with microbial activity, involving the combined effects of microbial metabolism, adsorption of CS@FeMn, and bioprecipitation. Analyses through high-throughput sequencing and KEGG pathway revealed that the presence of CBZ and Cu[2+] reshaped the structure of microbial community within the bioreactor, driving the regulation of functional genes and nitrogen metabolism-related genes to maintain metabolic stability. These findings indicated that the CS@FeMn bioreactor system presents an effective solution for simultaneously addressing multiple pollutants in water treatment, achieving high efficiencies in NO3[-]-N, CBZ, and Cu[2+] removal.}, }
@article {pmid40080180, year = {2025}, author = {Zhang, ZM and Zhao, SY and Liu, WQ and Wu, X and Tang, J and Li, YJ and Hu, XB and Zhou, YB and Dai, LX and Huang, MY and Lan, P and Sun, PH and Xu, J and Liu, J and Zheng, JX}, title = {Hybrid Molecules of Benzothiazole and Hydroxamic Acid as Dual-Acting Biofilm Inhibitors with Antibacterial Synergistic Effect against Pseudomonas aeruginosa Infections.}, journal = {Journal of medicinal chemistry}, volume = {}, number = {}, pages = {}, doi = {10.1021/acs.jmedchem.4c02517}, pmid = {40080180}, issn = {1520-4804}, abstract = {The ubiquitous opportunistic pathogen Pseudomonas aeruginosa (P. aeruginosa) causes biofilm-associated drug-resistant infections that often lead to treatment failure. Targeting the bacterium's quorum sensing (QS) and iron homeostasis presents a promising strategy to combat biofilm formation. This study synthesized benzothiazole-conjugated hydroxamic acid derivatives as dual-acting biofilm inhibitors, and compound JH21 was identified as the hit compound with potent submicromolar biofilm inhibitory activity (IC50 = 0.4 μM). Further mechanistic studies demonstrated not only that the production of virulence was decreased through mainly inhibiting QS system but also that JH21 competed for iron with the high-affinity siderophore pyoverdine, inducing iron deficiency and inhibiting biofilm. Moreover, JH21 significantly enhanced the efficacy of tobramycin and ciprofloxacin by 200- and 1000-fold, respectively, in a mouse wound infection model. These results emphasized the feasibility of dual-acting biofilm inhibitors against resistant P. aeruginosa infections and the potential of JH21 as a novel antibacterial synergist.}, }
@article {pmid40078565, year = {2025}, author = {Hong, S and Lu, H and Tian, D and Chang, Y and Lu, Q and Gao, F}, title = {Discovery of triazole derivatives for biofilm disruption, anti-inflammation and metal ion chelation.}, journal = {Frontiers in chemistry}, volume = {13}, number = {}, pages = {1545259}, doi = {10.3389/fchem.2025.1545259}, pmid = {40078565}, issn = {2296-2646}, abstract = {In the face of bacterial hazards to human health and resistance to multiple antibiotics, there is an urgent need to develop new antibiotics to meet the challenge. In this paper, the triazolyl heterocyclic (3-amino-1,2,4-triazole, D) was synthesised efficiently using thiourea as starting material. Finally, the end product E was obtained by aldehyde-amine condensation reaction and the structures of all compounds were determined by spectral analysis. In vitro antimicrobial activity showed that E10 had a MIC of 32 μg/mL against the tested Escherichia coli and 16 μg/mL against the tested Staphylococcus aureus strain. Meanwhile, E10 has a good anti-biofilm effect. Antibacterial mechanism studies have shown that E10 has a good membrane targeting ability, thus disrupting cell membranes, leading to leakage of intracellular proteins and DNA and accelerating bacterial death. In terms of anti-inflammation, E10 dose-dependently inhibits the levels of inflammatory factors NO and IL-6, which deserves further exploration in the treatment of asthma. The study of metal ion removal capacity showed that the synthesised triazole derivatives have high capacity to remove heavy metals Pb[2+], Cd[2+], Ca[2+], Mg[2+], Fe[3+],Cr[3+] and Al[3+] in the range of 42%-60%.}, }
@article {pmid40077829, year = {2025}, author = {Han, SL and Wang, J and Wang, HS and Yu, P and Wang, LY and Ou, YL and Ding, LJ and Washio, J and Takahashi, N and Zhang, LL}, title = {Extracellular Z-DNA Enhances Cariogenicity of Biofilm.}, journal = {Journal of dental research}, volume = {}, number = {}, pages = {220345251316822}, doi = {10.1177/00220345251316822}, pmid = {40077829}, issn = {1544-0591}, abstract = {Extracellular DNA (eDNA) is one of the core components of the extracellular matrix (ECM) in biofilms and provides attachment sites for microbes and other ECM components. However, little is known about the functions and underlying mechanisms of eDNA in the cariogenicity of dental plaque biofilms. A recent study demonstrated that conformational diversity of eDNA exists in biofilms, and the transition of eDNA from right-handed (B-DNA) to left-handed (Z-DNA) is associated with the structural stability and pathogenicity of biofilms. Caries-related biofilm is a complex multispecies microenvironment. The presence and biological function of the conformational transition of eDNA within this biofilm have not been previously reported. In this study, we found that extracellular Z-DNA is widely present in carious tissues and cariogenic biofilm, especially Streptococcus mutans, indicating its possible role in the occurrence and activity of dental caries. The content of extracellular Z-DNA showed species heterogeneity. The modulation of Z-DNA formation affected the level of extracellular polysaccharide. Increased formation of Z-DNA substantially strengthened the cariogenicity of the biofilm by increasing DNase resistance, structural density, and acid production. These insights provide a new perspective to understand the underlying function of the conformation transition of eDNA in promoting carious lesions, as well as a possible anti-biofilm strategy targeting extracellular Z-DNA.}, }
@article {pmid40076802, year = {2025}, author = {Guo, M and Ling, X and He, L and Gou, Y and Li, Z and Li, W}, title = {NapR Regulates the Expression of Phosphoserine Aminotransferase SerC to Modulate Biofilm Formation and Resistance to Serine Stress of Mycobacteria.}, journal = {International journal of molecular sciences}, volume = {26}, number = {5}, pages = {}, doi = {10.3390/ijms26052181}, pmid = {40076802}, issn = {1422-0067}, support = {2020YFA0907200//National Key R&amp;D Program of China/ ; 2022JJG130005//Guangxi Science Fund for Distinguished Young Scholars/ ; 32470034//National Natural Science Foundation of China/ ; 32360013//National Natural Science Foundation of China/ ; }, mesh = {*Biofilms/growth &amp; development ; *Gene Expression Regulation, Bacterial ; *Serine/metabolism ; *Bacterial Proteins/metabolism/genetics ; *Transaminases/metabolism/genetics ; *Promoter Regions, Genetic ; Mycobacterium smegmatis/genetics/metabolism/growth &amp; development ; Mycobacterium tuberculosis/genetics/metabolism ; Stress, Physiological ; Transcription Factors/metabolism/genetics ; }, abstract = {Mycobacterium tuberculosis is a formidable pathogen capable of establishing persistent infections within macrophages. To survive and thrive within the host environment, it has evolved intricate regulatory networks, including a diverse array of transcription factors that enable adaptation to various stresses encountered within the host. However, the mechanisms by which transcription factors regulate biofilm formation in M. tuberculosis remain incompletely understood. This study aimed to investigate the role of serC, encoding phosphoserine aminotransferase, and its regulation by NapR, a transcription factor, in mycobacterial physiology. NapR regulates serC through directly binding to its promoter. Notably, the regulatory effect and corresponding phenotypes vary due to distinct binding affinities of NapR for the serC promoter in different mycobacterial species. In Mycobacterium smegmatis, NapRMsm positively regulates biofilm formation, growth on solid media, and the transition from microcolonies to microcolonies by activating serCMsm. In the BCG vaccine, on the contrary, NapRBCG represses serCBCG, thus negatively regulating colony size and alleviating the growth inhibition caused by high concentrations of serine. Furthermore, proteomic analysis suggested NapR serves as a global transcriptional regulator in BCG vaccine strains by simultaneously modulating four metabolic pathways. These findings underscore the complex and strain-specific regulatory mechanisms governing serine metabolism in mycobacteria and provide valuable insights into the interplay between metabolism, gene regulation, and bacterial physiology.}, }
@article {pmid40076573, year = {2025}, author = {Bierowiec, K and Delmar, A and Karwańska, M and Siedlecka, M and Kumala-Ćwikła, A and Książczyk, M and Kapczyńska, K}, title = {Comparison of Staphylococcus pettenkoferi Isolated from Human Clinical Cases and Cat Carriers Regarding Antibiotic Susceptibility and Biofilm Production.}, journal = {International journal of molecular sciences}, volume = {26}, number = {5}, pages = {}, doi = {10.3390/ijms26051948}, pmid = {40076573}, issn = {1422-0067}, mesh = {Cats ; *Biofilms/drug effects/growth &amp; development ; Humans ; Animals ; *Staphylococcus/drug effects/genetics/isolation &amp; purification/physiology ; *Anti-Bacterial Agents/pharmacology ; *Staphylococcal Infections/microbiology/veterinary ; *Microbial Sensitivity Tests ; Drug Resistance, Multiple, Bacterial/genetics ; Cat Diseases/microbiology ; RNA, Ribosomal, 16S/genetics ; Male ; Female ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ; }, abstract = {Staphylococcus pettenkoferi (S. pettenkoferi) is a rare opportunistic bacterium not commonly found in healthy individuals or animals. S. pettenkoferi has increasing clinical significance in both veterinary and human medicine due to its multidrug resistance and biofilm-forming ability. This study analyzed 12 isolates of S. pettenkoferi collected from humans and cats and identified them using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and 16S rRNA and partial rpoB gene sequencing. All of the S. pettenkoferi were phenotypically resistant to penicillin, and almost all (except one human strain) were resistant to methicillin. Antibiotic susceptibility testing revealed a high prevalence of multidrug resistance in all human strains with frequent resistance to β-lactams, macrolides, and tetracyclines. A comparative analysis of human and feline isolates indicated the presence of shared resistance genes such as blaZ, mecA, and ermA. Biofilm production varied across isolates, with more potent biofilm formation abilities observed at elevated temperatures (39 °C) and time (48 h). These findings underscore the potential zoonotic risks of S. pettenkoferi and its role in managing multidrug-resistant infections.}, }
@article {pmid40076305, year = {2025}, author = {Komaniecka, I and Żebracki, K and Mazur, A and Suśniak, K and Sroka-Bartnicka, A and Swatek, A and Choma, A}, title = {The Absence of a Very Long Chain Fatty Acid (VLCFA) in Lipid A Impairs Agrobacterium fabrum Plant Infection and Biofilm Formation and Increases Susceptibility to Environmental Stressors.}, journal = {Molecules (Basel, Switzerland)}, volume = {30}, number = {5}, pages = {}, doi = {10.3390/molecules30051080}, pmid = {40076305}, issn = {1420-3049}, support = {2017/01/X/NZ1/00448 and 2018/31/B/NZ9/01755//National Centre of Sciences Poland/ ; }, mesh = {*Biofilms/growth &amp; development/drug effects ; *Lipid A/metabolism/chemistry ; *Fatty Acids/metabolism ; *Agrobacterium/genetics ; Plant Diseases/microbiology ; Mutation ; Stress, Physiological ; }, abstract = {The Agrobacterium fabrum C58 is a phytopathogen able to infect numerous species of cultivated and ornamental plants. During infection, bacteria genetically transform plant cells and induce the formation of tumours at the site of invasion. Bacterial cell wall components play a crucial role in the infection process. Lipopolysaccharide is the main component of Gram-negative bacteria's outer leaflet of outer membrane. Its lipophilic part, called lipid A, is built of di-glucosamine backbone substituted with a specific set of 3-hydroxyl fatty acids. A. fabrum incorporates a very long chain hydroxylated fatty acid (VLCFA), namely 27-hydroxyoctacosanoic acid (28:0-(27OH)), into its lipid A. A. fabrum C58 mutants deprived of this component due to mutation in the VLCFA's genomic region, have been characterised. High-resolution mass spectrometry was used to establish acylation patterns in the mutant's lipid A preparations. The physiological properties of mutants, as well as their motility, ability to biofilm formation and plant infectivity, were tested. The results obtained showed that the investigated mutants were more sensitive to environmental stress conditions, formed a weakened biofilm, exhibited impaired swimming motility and were less effective in infecting tomato seedlings compared to the wild strain.}, }
@article {pmid40076168, year = {2025}, author = {Almuhayya, S and Alshahrani, R and Alsania, R and Albassam, A and Alnemari, H and Babaier, R}, title = {Biofilm Formation on Three High-Performance Polymeric CAD/CAM Composites: An In Vitro Study.}, journal = {Polymers}, volume = {17}, number = {5}, pages = {}, doi = {10.3390/polym17050676}, pmid = {40076168}, issn = {2073-4360}, abstract = {Reinforced polymeric materials are investigated as novel non-metal alternatives for prosthetic frameworks. This study examined the adherence of Streptococcus mutans to three high-performance polymeric (HPP) composites focusing on their microstructural composition, wettability, and surface roughness. Three CAD/CAM HPP composites [two fiber-reinforced composites, CarboCad (CC) and TRINIA (TR), and one ceramic-reinforced polyether ether ketone, DentoPEEK (PK)], were sectioned into ten beam- and ten plate-shaped specimens from each material. Surface properties (n = 10) were analyzed by water wettability and roughness measurements (Ra and Rz). The biofilm adherence was determined by calculating the number of S. mutans through colony-forming units (CFUs). Representative images were obtained using a confocal laser scanning microscope (CLSM) and scanning electron microscopy (SEM). The data were analyzed using Welch one-way ANOVA and Dunnett T3 post hoc tests. The results showed significant differences in roughness (Ra) across the materials, ranked from highest to lowest as follows: TR, 0.231 µm; CC, 0.194 µm; and PK, 0.161 µm (p = 0.0001). The contact angle averages varied from 51.36° to 91.03°, with PK exhibiting the highest wettability (p = 0.0012). However, S. mutans adherence was markedly reduced in PK (1.96 CFU/mm[2], p = 0.0001) in comparison to TR and CC (2.86 and 2.98 CFU/mm[2], respectively). Consequently, the fiber-reinforced composites (CC and TR), despite their low wettability, exhibited greater susceptibility for bacterial adherence than the smoother and more wettable PK, highlighting the substantial impact of their surface roughness and microstructural variability.}, }
@article {pmid40074536, year = {2025}, author = {Lin, C and Zhang, N and Liang, Y and Gong, X and Zeng, Y and Long, H and Xie, Z}, title = {Roles of flgJ in biofilm formation of Vibrio alginolyticus.}, journal = {Journal of applied microbiology}, volume = {}, number = {}, pages = {}, doi = {10.1093/jambio/lxaf062}, pmid = {40074536}, issn = {1365-2672}, abstract = {AIM: This study aimed to investigate the role of two flgJ genes in flagellar assembly and biofilm regulation in Vibrio alginolyticus.<br><br>METHODS AND RESULTS: To investigate the functions of the flgJ, overexpression and gene knockout techniques were employed. Overexpression of flgJ1 enhanced the strain's growth capacity, leading to a rapid bacterial concentration that initiated biofilm formation. Additionally, this overexpression caused different aggregation patterns at various growth stages. In contrast, the knockout of flgJ1 resulted in the loss of the flagellum, reduced motility, and decreased growth. Interestingly, under static culture conditions, the flgJ1 mutant strain aggregated and grew at the air-liquid interface, accompanied by an increased concentration of intracellular c-di-GMP, which ultimately also promoted biofilm formation. Thus, both the absence and overexpression of flgJ1 led to increased biofilm formation. On the other hand, both gene knockout and overexpression of flgJ2 lacked any response under the experimental conditions.<br><br>CONCLUSION: FlgJ1 plays a crucial role in flagellar assembly and motility, while flgJ2 has been found to be non-functional. Both overexpression and knockout of the flgJ1 gene result in increased biofilm formation through distinct regulatory mechanisms. These findings enhance our understanding of the role of flgJ gene in regulating biofilm formation.}, }
@article {pmid40074093, year = {2025}, author = {He, L and He, X and Zhang, Y and Fan, X and Yang, T and Ji, X and Wang, Y and Zhou, J and Lin, C}, title = {Enhanced dissimilatory nitrate reduction to ammonium and electron transfer mechanisms in bidirectional electron transfer biofilm constructed by iron phthalocyanine.}, journal = {Bioresource technology}, volume = {}, number = {}, pages = {132381}, doi = {10.1016/j.biortech.2025.132381}, pmid = {40074093}, issn = {1873-2976}, abstract = {Bidirectional electron transfer biofilms (BETB) could efficiently reduce nitrate without accumulating nitrite, representing a promising biological electrochemical denitrification technology. This study utilized iron phthalocyanine modified carbon felt (FePc-CF) to enrich electroactive bacteria, constructing a long-term stable FePc-BETB. Its nitrate removal rate reached 91%, far exceeding the traditional nitrate-reducing biocathode (45%) and Con-BETB (46%). The dissimilatory nitrate reduction to ammonium (DNRA) dominated nitrate reduction in FePc-BETB, consuming 35% of the total electrons. Additionally, FePc-BETB effectively reduced the accumulation of NO2[-]-N and N2O. Electrochemical analysis demonstrated FePc-BETB exhibited stronger electrochemical activity and electron transfer capability. Mediated electron transfer (MET) enhanced by increased extracellular humic acid in FePc-BETB favored the electron supplement for nitrate removal. The relative abundance of nrfA, marker of the DNRA, increased significantly. This study provided new insights into regulating denitrification and DNRA pathways and treating nitrate wastewater lacking electron donors.}, }
@article {pmid40074047, year = {2025}, author = {Liaqat, I and Qaiser, I and Aftab, MN and Ali, S and Latif, AA and Naseem, S and Afzaal, M and Khalid, A}, title = {Anti-biofilm potential of some fish probiotics, alone and in combination with antibiotics against isolated aquaculture pathogens; a preliminary data.}, journal = {Microbial pathogenesis}, volume = {}, number = {}, pages = {107437}, doi = {10.1016/j.micpath.2025.107437}, pmid = {40074047}, issn = {1096-1208}, abstract = {This study aims to isolate and identify both diseased and healthy fish pathogens of Ctenopharyngodon idella, Labeo rohita and Oreochromis niloticus and assess their antibacterial and biofilm supressing activities against fish pathogens. It explores their potential to inhibit and degrade biofilms, serving as an alternative to antibiotics in aquaculture while enhancing fish health and disease resistance. Furthermore, the research endeavors to assess the biofilm degradation potential of antibiotics and probiotics, both individually and in combination. The biofilm-forming potential of pathogens was assessed both qualitatively and quantitatively using the Congo red assay, cover slip, and test tube methods. Additionally, genomic sequencing through 16S rRNA ribotyping revealed the species level identification of four pathogenic and twelve probiotic strains. Three pathogens, Staphylococcus sciuri, Pseudomonas aeruginosa, and Staphylococcus xylosus, showed significant biofilm formation at day 5, while the pathogen Niallia circulans expressed maximum biofilm formation on day 7. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of antibiotics were evaluated against pathogenic strains. Antibiotic susceptibility testing revealed significant inhibition zones. MIC and MBC values ranged from 0.10 mg/ml to 85.00 mg/ml, with the agar well and disk diffusion methods demonstrating strong inhibitory effects against the pathogenic strains. Notably, fish probiotics either alone or in combination with antibiotics exhibited significant inhibition and anti-biofouling activity across three different concentrations (1/2 MIC, 1MIC, 2XMIC). The biofilm eradication values were statistically significant (p < 0.005). The findings affirm the effectiveness of the antibiotics (ampicillin, levofloxacin, kanamycin and oxytetracycline) and probiotics (Bacullus altitudinis, Bacillus pumilus, Mammaliicoccus sciuri) employed in preventing and dispersing biofilms formed by isolated fish pathogens (S. sciuri, P. aeruginosa and N. circulans). The current study explores the use of probiotics to enhance fish immunity, reduce disease risk without promoting antibiotic resistance, and disrupt pathogenic biofilms to control infections. Unlike antibiotics, probiotics are biodegradable and eco-friendly, minimizing harm to aquatic ecosystems and beneficial microbes.}, }
@article {pmid40073550, year = {2025}, author = {Zhang, Q and E, J and Guo, X and Jiao, S and Wang, J}, title = {Sucrose improve Lactiplantibacillus plantarum LIP-1's tolerance to heat by increasing biofilm production.}, journal = {International journal of food microbiology}, volume = {434}, number = {}, pages = {111136}, doi = {10.1016/j.ijfoodmicro.2025.111136}, pmid = {40073550}, issn = {1879-3460}, abstract = {Optimizing the carbon source to increase biofilm production and thus boost the heat tolerance of strains is a promising strategy. However, related research is scarce. This study investigated the effects of varying glucose and sucrose amounts added to MRS medium on biofilm production and heat tolerance by Lactiplantibacillus plantarum LIP-1. Transcriptomic, proteomic, and metabolomic approaches were combined to analyze the intrinsic mechanism underlying the sucrose-induced increase in biofilm production. We then investigated the protective role of the biofilm for the strain. Compared with the control group (2 % glucose), biofilm production in the experimental group (2 % glucose+2 % sucrose) increased by 27 %, and after heat treatment (75 °C for 40 s), the experimental group demonstrated a 38 % increase in heat tolerance. Multiomic results unveiled that biofilm synthesis-related metabolism pathways were altered in the experimental group compared with the control group. When the expression of key genes and the enzymes they encode(sacA, metC, mccB, and CTH) was upregulated, L-homocysteine was synthesized. According to metabolomics results, the L-homocysteine content in the experimental group increased to twice that in the control group. This resulted in a 37 % increase in the extracellular protein content of biofilms. The biofilm inhibition test confirmed that this increase in extracellular protein content was the primary factor augmenting the strain's heat tolerance. The findings suggested that adding sucrose to MRS medium for boosting biofilm production is a viable technical approach that enhances cell tolerance to heat.}, }
@article {pmid40073138, year = {2025}, author = {Sun, B and Guo, J and Hao, B and Cao, Y and Chan, TKF and Sun, M and Sung, JJY and Zhang, L}, title = {Liquid-bodied antibiofilm robot with switchable viscoelastic response for biofilm eradication on complex surface topographies.}, journal = {Science advances}, volume = {11}, number = {11}, pages = {eadt8213}, doi = {10.1126/sciadv.adt8213}, pmid = {40073138}, issn = {2375-2548}, mesh = {*Biofilms/drug effects/growth &amp; development ; Animals ; *Robotics ; Mice ; Swine ; Viscosity ; Elasticity ; Humans ; Hydrogels/chemistry/pharmacology ; Surface Properties ; }, abstract = {Recalcitrant biofilm infections pose a great challenge to human health. Micro- and nanorobots have been used to eliminate biofilm infections in hard-to-reach regions inside the body. However, applying antibiofilm robots under physiological conditions is limited by the conflicting demands of accessibility and driving force. Here, we introduce a liquid-bodied antibiofilm robot constructed by a dynamically cross-linked magnetic hydrogel. Leveraging the viscoelastic response of the robot enables it to adapt to complex surface topographies such as medical meshes and stents. Upon actuation, the robot can mechanically destroy the biofilm matrix, chemically deactivate bacterial cells, and collect disrupted biofilm debris. The robot's antibiofilm performance is studied in vitro and demonstrated on a medical mesh and a biliary stent. Tracking and navigation under endoscopy and x-ray imaging in an ex vivo porcine bile duct are demonstrated. Last, in vivo antibiofilm treatment is conducted by indwelling infected stents into mice's abdominal cavity and clearing the biofilm infection using the proposed robot.}, }
@article {pmid40073033, year = {2025}, author = {, }, title = {Retraction: The biofilm formation and antibiotic resistance of bacterial profile from endotracheal tube of patients admitted to intensive care unit in southwest of Iran.}, journal = {PloS one}, volume = {20}, number = {3}, pages = {e0320615}, doi = {10.1371/journal.pone.0320615}, pmid = {40073033}, issn = {1932-6203}, }
@article {pmid40071724, year = {2025}, author = {Zhang, S and He, W and Dong, J and Chan, YK and Lai, S and Deng, Y}, title = {Tailoring Versatile Nanoheterojunction-Incorporated Hydrogel Dressing for Wound Bacterial Biofilm Infection Theranostics.}, journal = {ACS nano}, volume = {}, number = {}, pages = {}, doi = {10.1021/acsnano.4c15743}, pmid = {40071724}, issn = {1936-086X}, abstract = {Wound-infected bacterial biofilms are protected by self-secreted extracellular polymer substances (EPS), which can confer them with formidable resistance to the host's immune responses and antibiotics, and thus delays in diagnosis and treatment can cause stubborn infections and life-threatening complications. However, tailoring an integrated theranostic platform with the capability to promptly diagnose and treat wound biofilm infection still remains a challenge. Herein, a versatile erbium-doped carbon dot-encapsulated zeolitic imidazolate framework-8 (Er:CDs@ZIF-8) nanoheterojunction (C@Z nano-HJ) is tailored and incorporated into gelatin methacrylate/poly(N-hydroxyethyl acrylamide) (GelMA/PHEAA)-based tough and sticky hydrogel dressing (GH-C@Z) to achieve wound biofilm infection-integrated theranostic application. Stimulated by the acidic microenvironment of the biofilm, the turn-on response of the C@Z in the dressing assists the biofilm infection monitoring by exhibiting cyan fluorescence. Meanwhile, C@Z can effectively destroy the EPS barrier and accomplish photothermal-photodynamic-ion interference synergistic antibacterial therapy under near-infrared light. Furthermore, after the effective eradication of biofilm, the potent antioxidant properties of released Er:CDs allow the dressing to attenuate reactive oxygen species and mitigate inflammatory responses, which finally promote collagen deposition and neovascularization to accelerate wound healing. Overall, this tailored wound dressing provides insight into the development of versatile diagnostic and therapeutic platforms for bacterial biofilm infections.}, }
@article {pmid40071171, year = {2025}, author = {Rivet, C and Elliott, JT and Gunn, JR and Sottosanti, JS and Fearing, BV and Hsu, JR and Gitajn, IL}, title = {Rabbit model of a biofilm-contaminated, percutaneous orthopaedic endoprosthesis.}, journal = {OTA international : the open access journal of orthopaedic trauma}, volume = {8}, number = {1 Suppl}, pages = {e384}, doi = {10.1097/OI9.0000000000000384}, pmid = {40071171}, issn = {2574-2167}, abstract = {Preclinical models of osseointegrated orthopaedic implants tend to focus on implant stability, surface modifications to enhance integration with host tissue, and reduction in iatrogenic contamination through antibiotic-eluting/bacteria-resistant coatings. While these studies are imperative to early success in osseointegration, continued success of percutaneous devices throughout the lifespan of the patient is also critically important. A perpetual challenge to the implant is formation of bacterial biofilm on the abutment. Once adhered, biofilm-based bacteria are recalcitrant and readily contaminate the subcutaneous soft tissue of the stoma. To this end, the rabbit model reported herein replicates the clinical scenario of a patient with a biofilm-contaminated abutment. This model enables preclinical testing of advanced therapeutics beyond the traditional antibiotic-based approach, potentially increasing the longevity of the device.}, }
@article {pmid40070951, year = {2025}, author = {Aflakian, F and Hashemitabar, G}, title = {Biosynthesized silver nanoparticles at subinhibitory concentrations as inhibitors of quorum sensing, pathogenicity, and biofilm formation in Pseudomonas aeruginosa PAO1.}, journal = {Heliyon}, volume = {11}, number = {4}, pages = {e42899}, doi = {10.1016/j.heliyon.2025.e42899}, pmid = {40070951}, issn = {2405-8440}, abstract = {Pseudomonas aeruginosa infections associated with biofilm are a significant clinical challenge due to the limited efficacy of traditional antibiotics or combination therapies. Hence, exploring novel strategies and assessing different compounds for their anti-biofilm or anti-quorum sensing (QS) properties is imperative. One of the various applications of silver nanoparticles (AgNPs) is to use them as an antimicrobial agent to target bacteria resistant to common antibiotics. This study evaluates the anti-biofilm and anti-virulence effect of biosynthesized AgNPs against P. aeruginosa PAO1 at subinhibitory concentration levels. Minimum inhibitory concentrations (MICs) and biofilm formation capacity were evaluated by the microdilution method and crystal violet method, respectively. Motility assay and virulence factors were investigated in the presence of AgNPs. It was observed that green-synthesized AgNPs at sub-MIC (50 μg/mL) suppressed P. aeruginosa biofilm formation by 78 %. Increased dose-dependent inhibitory effects on virulence phenotypes (LasB elastase, LasA protease, pyocyanin, and motility) regulated by QS were observed. In addition, the relative expression levels of biofilm-related genes including algC, pslA, and pelA were analyzed using RT-qPCR. The expression level of QS-regulated biofilm genes after AgNPs treatment sub-MIC led to a decrease in the expression of algC, pslA, and pelA by 77 %, 83 %, and 68 %, respectively. The findings of this study demonstrated how green AgNPs can effectively inhibit QS at sub-MIC concentrations, indicating their potential as antivirulence agents to deal with challenges related to biofilm formation and antimicrobial resistance in P. aeruginosa. This presents a promising alternative to traditional antibiotics in antimicrobial therapy.}, }
@article {pmid40069969, year = {2025}, author = {Schneider, RE and Hamdan, JV and Rumbaugh, KP}, title = {Biofilm Dispersal and Wound Infection Clearance With Preclinical Debridement Agents.}, journal = {International wound journal}, volume = {22}, number = {3}, pages = {e70145}, doi = {10.1111/iwj.70145}, pmid = {40069969}, issn = {1742-481X}, support = {R21 AI175650-01A1/NH/NIH HHS/United States ; MIDRP MI230044//U.S. Department of Defense/ ; }, mesh = {*Biofilms/drug effects ; *Debridement/methods ; Animals ; *Pseudomonas aeruginosa/drug effects ; *Pseudomonas Infections/drug therapy/therapy ; Wound Infection/drug therapy/microbiology/therapy ; Disease Models, Animal ; Anti-Bacterial Agents/therapeutic use ; Wound Healing/drug effects ; Glycoside Hydrolases/pharmacology ; Humans ; Surgical Wound Infection/drug therapy/therapy/microbiology ; }, abstract = {Biofilms complicate wound care by causing recurrent infections that are often resistant to debridement and are highly antibiotic-tolerant. We investigated whether the addition of a biofilm dispersal agent could improve the efficacy of debridement. The previous studies have indicated that a glycoside hydrolase cocktail of alpha-amylase and cellulase can act as a potent biofilm dispersal agent. With in vitro and ex vivo Pseudomonas aeruginosa biofilm models, we compared glycoside hydrolases against other, clinically relevant, enzymatic debridement agents (papain, bromelain, and collagenase). Glycoside hydrolase biofilm dispersal was dose-dependent. However, at doses of 1% or above, glycoside hydrolases outperformed, or were comparable, to other enzymatic debridement agents. With our in vivo surgical wound infection model, we evaluated biofilm dispersal using infection dissemination as a proxy. We found that sharp debridement followed by multiple glycoside hydrolase treatments enhanced biofilm dispersal. Furthermore, a single dose of glycoside hydrolase in combination with debridement decreased infection load in acute wounds. Similarly, when we treated established 5-day-old infections, we saw a decrease in infection load and no infection dissemination. Overall, our data suggest that debridement enhances the efficacy of a topical antibiotic ointment, allowing for greater infection clearance.}, }
@article {pmid40069551, year = {2025}, author = {Balato, M and Vitelli, M and Petrarca, C and Minucci, S and Aversa, M and Galdiero, U and Catania, MR and Roscetto, E and Costanzo, L and Chiariello, AG and Mariconda, M and Balato, G}, title = {On the effectiveness of electrical characterization of mature Staphylococcal Biofilm.}, journal = {Scientific reports}, volume = {15}, number = {1}, pages = {8445}, pmid = {40069551}, issn = {2045-2322}, support = {2022Z8C472//Italian Ministero dell'Universit&#xe0; e della Ricerca (MUR) in the framework of "PRIN 2022 - "Progetti di Rilevante Interesse Nazionale/ ; 2022Z8C472//Italian Ministero dell'Universit&#xe0; e della Ricerca (MUR) in the framework of "PRIN 2022 - "Progetti di Rilevante Interesse Nazionale/ ; 2022Z8C472//Italian Ministero dell'Universit&#xe0; e della Ricerca (MUR) in the framework of "PRIN 2022 - "Progetti di Rilevante Interesse Nazionale/ ; 2022Z8C472//Italian Ministero dell'Universit&#xe0; e della Ricerca (MUR) in the framework of "PRIN 2022 - "Progetti di Rilevante Interesse Nazionale/ ; 2022Z8C472//Italian Ministero dell'Universit&#xe0; e della Ricerca (MUR) in the framework of "PRIN 2022 - "Progetti di Rilevante Interesse Nazionale/ ; 2022Z8C472//Italian Ministero dell'Universit&#xe0; e della Ricerca (MUR) in the framework of "PRIN 2022 - "Progetti di Rilevante Interesse Nazionale/ ; 2022Z8C472//Italian Ministero dell'Universit&#xe0; e della Ricerca (MUR) in the framework of "PRIN 2022 - "Progetti di Rilevante Interesse Nazionale/ ; 2022Z8C472//Italian Ministero dell'Universit&#xe0; e della Ricerca (MUR) in the framework of "PRIN 2022 - "Progetti di Rilevante Interesse Nazionale/ ; 2022Z8C472//Italian Ministero dell'Universit&#xe0; e della Ricerca (MUR) in the framework of "PRIN 2022 - "Progetti di Rilevante Interesse Nazionale/ ; }, mesh = {*Biofilms/growth &amp; development ; *Dielectric Spectroscopy ; *Methicillin-Resistant Staphylococcus aureus/physiology ; Microscopy, Confocal ; }, abstract = {In this paper, the authors describe an experimental study carried out on biological samples consisting of a 96-h mature Methicillin-Resistant-Staphylococcus-Aureus biofilm. The initial objective was to electrically characterize the biofilm using impedance spectroscopy, by scanning a wide range of frequencies [1 Hz ÷ 10 MHz]. Concurrently, confocal microscopy observations, XTT assays, crystal violet staining method and colony-forming unit assay were performed to characterize the biological activity. The experimental investigation unexpectedly demonstrated that the reproducibility of measurement data was significantly affected by the destructive interaction between the electric field and the biofilm. This interaction was found to be strongly dependent on both the amplitude of the field and the exposure time. Moreover, a significative reduction of total biomass of the biofilm was found in a specific frequency range [10 kHz ÷ 100 kHz]. The results suggest several limitations of impedance spectroscopy as a tool for biofilm identification, since the "sample under test" must not be altered during the measurement process. Conversely, they demonstrate the deleterious impact of the electric field on the biofilm, thereby unveiling a potentially efficacious therapeutic paradigm for biofilm treatment. We expect that the open issues highlighted in this paper will be a source of inspiration for further understanding of the mechanism of interaction between the electric field and biofilm, both in terms of treatment and diagnosis.}, }
@article {pmid40069148, year = {2025}, author = {Rindi, L and He, J and Miculan, M and Dell'Acqua, M and Pè, ME and Benedetti-Cecchi, L}, title = {Legacies of temperature fluctuations promote stability in marine biofilm communities.}, journal = {Nature communications}, volume = {16}, number = {1}, pages = {2442}, pmid = {40069148}, issn = {2041-1723}, mesh = {*Biofilms/growth &amp; development ; *Temperature ; *Climate Change ; *Ecosystem ; Biodiversity ; Microbiota/physiology ; Aquatic Organisms/physiology ; Seawater/microbiology ; }, abstract = {The increasing frequency and intensity of extreme climate events are driving significant biodiversity shifts across ecosystems. Yet, the extent to which these climate legacies will shape the response of ecosystems to future perturbations remains poorly understood. Here, we tracked taxon and trait dynamics of rocky intertidal biofilm communities under contrasting regimes of warming (fixed vs. fluctuating) and assessed how they influenced stability dimensions in response to temperature extremes. Fixed warming enhanced the resistance of biofilm by promoting the functional redundancy of stress-tolerance traits. In contrast, fluctuating warming boosted recovery rate through the selection of fast-growing taxa at the expense of functional redundancy. This selection intensified a trade-off between stress tolerance and growth further limiting the ability of biofilm to cope with temperature extremes. Anticipating the challenges posed by future extreme events, our findings offer a forward-looking perspective on the stability of microbial communities in the face of ongoing climatic change.}, }
@article {pmid40067245, year = {2025}, author = {Charles-Nino, CL and Desai, GM and Koroneos, N and Hamed, MF and Jain, N and Lopes, W and Braswell, A and Linares, A and Munzen, ME and Nosanchuk, JD and Vainstein, MH and Martinez, LR}, title = {Reduced growth and biofilm formation at high temperatures contribute to Cryptococcus deneoformans dermatotropism.}, journal = {Disease models &amp; mechanisms}, volume = {}, number = {}, pages = {}, doi = {10.1242/dmm.052141}, pmid = {40067245}, issn = {1754-8411}, support = {AI145559//National Institute of Allergy and Infectious Diseases/ ; T90DE021990/R90DE022530/DE/NIDCR NIH HHS/United States ; AI171093//Division of Intramural Research, National Institute of Allergy and Infectious Diseases/ ; 313620/2021-0//CNPq/ ; 405934/2022-0//The National Institute of Science and Technology INCT Funvir/ ; //UF McKnight Brain Institute Accelerator Program/ ; }, abstract = {Cryptococcus deneoformans (Cd) and C. neoformans (Cn) differ in geographic prevalence and dermatotropism, with Cd strains more commonly isolated from temperate regions and skin infections. Rising global temperatures prompt concerns regarding selection for environmental fungal species with increased thermotolerance, as high mammalian temperatures provide protection against many fungal species. Cd and Cn strains exhibit variations in thermal susceptibility, with Cd strains being more susceptible to higher temperatures. Here, we identified differences in capsular polysaccharide release, adhesion, and biofilm formation between strains both in vivo and in vitro. Histological results suggest the dermatotropic predilection associated with Cd relates to biofilm formation, possibly facilitating latency and extending fungal survival through protection from high temperatures. We demonstrated that Cn strains were more tolerant to mammalian and febrile temperatures than Cd strains. Similarly, Cd strains showed reduced expression of heat-shock protein 60 and 70, after prolonged exposure to high temperature. Our findings suggest that fungal adhesion, biofilm formation, inflammation, and thermotolerance contribute to tissue tropism and disease manifestation by Cn and Cd, supporting the recently assigned species distinction to each of these serotypes.}, }
@article {pmid40067049, year = {2025}, author = {Gross, N and Muhvich, J and Ching, C and Gomez, B and Horvath, E and Nahum, Y and Zaman, MH}, title = {Effects of microplastic concentration, composition, and size on Escherichia coli biofilm-associated antimicrobial resistance.}, journal = {Applied and environmental microbiology}, volume = {}, number = {}, pages = {e0228224}, doi = {10.1128/aem.02282-24}, pmid = {40067049}, issn = {1098-5336}, abstract = {UNLABELLED: Microplastics (MPs) have emerged as a significant environmental pollutant with profound implications for public health, particularly as substrates to facilitate bacterial antimicrobial resistance (AMR). Recently, studies have shown that MPs may accommodate biofilm communities, chemical contaminants, and genetic material containing AMR genes. This study investigated the effects of MP concentration, composition, and size on the development of multidrug resistance in Escherichia coli. Specifically, we exposed E. coli to varying concentrations of different MP types, including polyethylene, polystyrene, and polypropylene, across a range of sizes (3-10, 10-50, and 500 µm). Results indicated that the biofilm cells attached to MPs had elevated multidrug resistance (in E. coli. Notably, MPs exhibited a higher propensity for facilitating biofilm and resistance than control substrates such as glass, likely due to their hydrophobicity, greater adsorption capacities, and surface chemistries. Notably, we found that the bacteria passaged with MPs formed stronger biofilms once the MPs were removed, which was associated with changes in motility. Thus, MPs select cells that are better at forming biofilms, which can lead to biofilm-associated AMR and recalcitrant infections in the environment and healthcare setting. Our study highlights the importance of developing effective strategies to address the challenges posed by MPs.<br><br>IMPORTANCE: Antimicrobial resistance (AMR) is one of the world's most pressing global health crises. With the pipeline of antibiotics running dry, it is imperative that mitigation strategies understand the mechanisms that drive the genesis of AMR. One emerging dimension of AMR is the environment. This study highlights the relationship between a widespread environmental pollutant, microplastics (MPs), and the rise of drug-resistant bacteria. While it is known that MPs facilitate resistance through several modes (biofilm formation, plastic adsorption rates, etc.), this study fills the knowledge gap on how different types of MPs are contributing to AMR.}, }
@article {pmid40066382, year = {2025}, author = {Pandey, A and Yadav, R and Mishra, V and Sharma, A and Saroj, SK and Yadav, R and Rynjah, JO and Bhansali, S and Sharma, A and Shekar, GC and Yadav, S and Goyal, A and Tilak, R and Aggarwal, SK}, title = {To Study the Incidence of Biofilm Formation, its Microbiology and its Effect on the Development of Acute and Chronic Rhinosinusitis- A Prospective Study.}, journal = {Indian journal of otolaryngology and head and neck surgery : official publication of the Association of Otolaryngologists of India}, volume = {77}, number = {1}, pages = {34-40}, doi = {10.1007/s12070-024-05091-y}, pmid = {40066382}, issn = {2231-3796}, abstract = {Bacterial biofilms are organised complex structures having polymicrobial nature in a single community, which provide protection to bacteria from antibiotics by various means. The aim of our study was to determine the prevalence of biofilm-forming bacteria in clinical isolates of acute and chronic rhinosinusitis (ARS and CRS) patients with sinonasal mucopurulence. To know the incidence of bacterial biofilms in patient with ARS and CRS, to study the microbiology of bacterial biofilms in ARS and CRS, to assess the role and effects of biofilm in ARS and CRS and to correlate the association between the formation of the biofilm and development of rhinosinusitis. This prospective study was carried out at a tertiary care centre in Eastern part of India, in which 60 patients were taken as sample size. All patients of rhinosinusitis between age-group of 10 to70 years, who came to our out-patient department, were taken for our study. Biofilm formation was observed in 50% cases and were absent in 50% cases of chronic rhinosinusitis in our study. 83.3% (50) of patients out of 60 patients got improved after treatment and recurrence was observed in only 16.6% (10) of patients. Recurrence was more at 3 months follow-up as compared to follow-up at 1 month, though it was not statistically significant. Though our study highlighted the incidence and role of biofilms in the development of chronic rhinosinusitis, but few more randomized controlled studies involving larger sample sizes should be done to exactly determine the pathophysiological role of biofilms in the development and recurrence of acute and chronic rhinosinusuitis.}, }
@article {pmid40066315, year = {2025}, author = {Neetu,  and Pal, S and Subramanian, S and Ramya, TNC}, title = {Cellulophaga algicola alginate lyase and Pseudomonas aeruginosa Psl glycoside hydrolase inhibit biofilm formation by Pseudomonas aeruginosa CF2843 on three-dimensional aggregates of lung epithelial cells.}, journal = {Biofilm}, volume = {9}, number = {}, pages = {100265}, doi = {10.1016/j.bioflm.2025.100265}, pmid = {40066315}, issn = {2590-2075}, abstract = {Pseudomonas aeruginosa is an opportunistic pathogen that produces a biofilm containing the polysaccharides, alginate, Psl, and Pel, and causes chronic lung infection in cystic fibrosis patients. Others and we have previously explored the use of alginate lyases in inhibiting P. aeruginosa biofilm formation on plastic and lung epithelial cell monolayers. We now employ a more physiologically representative model system, i.e., three-dimensional aggregates of A549 lung epithelial cells cultured under conditions of microgravity in a rotary cell culture system to mimic the natural lung environment, and a previously isolated clinical strain, Pseudomonas aeruginosa CF2843 that we engineered by transposon-mediated integration to express Green Fluorescent Protein and for which we also report the complete genome sequence. Immunostaining and lectin binding studies indicated that the three-dimensional cell aggregates harbored sialylated and fucosylated epitopes as well as Muc1, Muc5Ac, and β-catenin on their surfaces, suggestive of mucin secretion and the presence of tight junctions, hallmark features of lung epithelial tissue. Using this validated model system with confocal microscopy and viable bacterial counts as readouts, we demonstrated that Cellulophaga algicola alginate lyase and Pseudomonas aeruginosa Psl glycoside hydrolase, but not Pseudomonas aeruginosa Pel glycoside hydrolase, inhibit biofilm formation by Pseudomonas aeruginosa on three-dimensional lung epithelial cell aggregates.}, }
@article {pmid40066272, year = {2025}, author = {Martinet, MG and Thomas, M and Bojunga, J and Pletz, MW and Vehreschild, MJGT and Würstle, S}, title = {The landscape of biofilm models for phage therapy: mimicking biofilms in diabetic foot ulcers using 3D models.}, journal = {Frontiers in microbiology}, volume = {16}, number = {}, pages = {1553979}, doi = {10.3389/fmicb.2025.1553979}, pmid = {40066272}, issn = {1664-302X}, abstract = {Diabetic foot ulcers (DFU) affect up to 15-25% of patients suffering from diabetes and are considered a global health concern. These ulcers may result in delayed wound healing and chronic infections, with the potential to lead to amputations. It has been estimated that 85% of diabetes-related amputations are preceded by a diagnosis of DFU. A critical factor in the persistence of this disease is the presence of polymicrobial biofilms, which generally include Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. The involvement of diabetic comorbidities such as ischemia, hyperglycemia, and immune-compromised status creates a perfect niche for these bacteria to evade the body's immune response and persist as biofilms. Bacteriophage therapy can target and lyse specific bacteria and is emerging as an effective treatment for biofilm-related infections. While this treatment shows promise in addressing chronic wounds, our current models, including animal and static systems, fail to capture the full complexity of DFU. Innovative approaches such as 3D bioengineered skin models, organoid models, and hydrogel-based systems are being developed to simulate DFU microenvironments more accurately in 3D without using ex vivo or animal tissues. These advanced models are critical for evaluating bacteriophage efficacy in biofilm-associated DFU, aiming to enhance preclinical assessments and improve therapeutic outcomes for DFU patients.}, }
@article {pmid40066049, year = {2025}, author = {Moreno, J and Diana, L and Martínez, M and Iribarnegaray, V and Puentes, R}, title = {Comprehensive analysis of antimicrobial resistance, biofilm formation and virulence factors of staphylococci isolated from bovine mastitis.}, journal = {Heliyon}, volume = {11}, number = {4}, pages = {e42749}, doi = {10.1016/j.heliyon.2025.e42749}, pmid = {40066049}, issn = {2405-8440}, abstract = {Bovine mastitis, a prevalent disease, is often attributed to staphylococci species. These microorganisms can express a diverse array of virulence genes and have the capability to form biofilms, establishing a robust defense against antimicrobials and host immune responses. In this study, we analyzed 191 Staphylococcus spp., of which 81 % were identified as Staphylococcus aureus, and 19 % as non-aureus staphylococci (NAS), including species such as S. borealis, S. chromogenes, S. haemolyticus, S. saprophyticus, S. capitis, S. ratti, and S. pasteuri. Our analysis involved determining antimicrobial susceptibility profiles, assessing biofilm-forming capacities, and identifying genes associated with virulence, biofilm formation, adhesion, and antimicrobial resistance. Notably, 17.2 % of the strains exhibited resistance to penicillin, with 97 % carrying the blaZ gene, while 9.4 % demonstrated resistance to erythromycin. All strains were sensitive to gentamicin and cefoxitin. Additionally, resistance was observed for clindamycin (8.4 %) and tetracycline (1.0 %). Concerning biofilm development, 2.6 % displayed no formation, 24.6 % were categorized as weak producers, 47.1 % as moderate, and 25.7 % as strong formers. Our investigation also unveiled the presence of virulence genes, such as superantigens like sea (4.7 %), seb (3.7 %), sec (8.4 %), sed (0.5 %), and tst (6.8 %); Panton-Valentine leukocidin (pvl) (59.7 %); haemolysins hla (88.5 %) and hlb (91.1 %); genes responsible for biofilm production icaA (87.9 %), icaD (78.5 %), and bap (4.2 %); and adhesion genes fnbpA (89.5 %), fnbpB (20.4 %), and clfA (89.0 %). Additionally, the strains were categorized into four groups based on their virulence attributes, revealing differences between S. aureus and NAS, with the latter showing a lower presence of the studied genes compared to S. aureus strains. This research sheds light on the resistance and virulence profiles of staphylococci strains associated with bovine mastitis, providing valuable insights for potential treatment approaches.}, }
@article {pmid40064461, year = {2025}, author = {Conquista, CM and Braga, AS and Francese, MM and Ferrari, CR and Silva, AL and Pollo, LHD and Santos, PSDS and Magalhães, AC}, title = {Effect of 70 Gy tumor therapeutic radiation applied intermittently or directly on microcosm biofilm composition and dental hard tissues and its potential to cause dental caries.}, journal = {Journal of dentistry}, volume = {}, number = {}, pages = {105678}, doi = {10.1016/j.jdent.2025.105678}, pmid = {40064461}, issn = {1879-176X}, abstract = {OBJECTIVES: This study compared total (70 Gy, one session) and intermittent (35 sessions of 2 Gy) tumor radiation protocols on tooth morphology (n=5) using Scanning Electron Microscopy-Energy Dispersive X-ray (SEM-EDX) and on microcosm biofilm microbiota (n=12) through colony-forming unit (CFU) counts for Candida spp., total microorganisms, Streptococcus mutans, and total lactobacillus. It also assessed "radiation caries" development via Transverse Microradiography (TMR, n=12).<br><br>METHODS: Bovine enamel and root dentin were divided into three groups (n=17): total radiation (1); intermittent radiation (2); and no radiation-control (3). Biofilm was produced using saliva from irradiated (for 1 and 2) or non-irradiated patients (for 3) (n=3 donors) combined with McBain saliva with 0.2% sucrose for 5 days. Data were analyzed using ANOVA/Tukey, t-test, and Kruskal-Wallis/Dunn's tests (p<0.05).<br><br>RESULTS: S. mutans and Candida spp. were observed on irradiated dentin compared to control, but these microorganisms were absent in enamel biofilm (S. mutans only in 50% and 12.5% of intermittent and total irradiated enamel). Total microorganisms and lactobacillus numbers were similar between groups, except for total microorganisms in irradiated enamel vs. control (p<0.037). No significant differences in mineral loss or lesion depth were detected between protocols or tissues (p>0.05). SEM-EDX revealed slight differences in magnesium (p=0.0439) and calcium (p=0.0216) content in intermittently irradiated dentin.<br><br>CONCLUSIONS: Despite increased cariogenic microorganisms in irradiated biofilm, no greater susceptibility to "radiation caries" was observed under this model.<br><br>CLINICAL SIGNIFICANCE: Although the radiotherapy alters oral microbiota and dental tissue morphology, these changes alone do not increase radiation-induced caries risk. Other factors, as salivary changes and diet, need to be better studied.}, }
@article {pmid40064370, year = {2025}, author = {Johnston, W and Kean, R}, title = {Development of a polymicrobial host-bacterial interface biofilm model for bacterial vaginosis.}, journal = {Anaerobe}, volume = {}, number = {}, pages = {102952}, doi = {10.1016/j.anaerobe.2025.102952}, pmid = {40064370}, issn = {1095-8274}, abstract = {Bacterial vaginosis (BV) is characterised by a polymicrobial biofilm forming on the vaginal epithelium. In this study, we have developed a host-pathogen model of BV to replicate disease. We demonstrated tissue colonisation by four key vaginal pathobionts that formed metronidazole tolerant biofilms, with subtle changes in cytotoxicity and inflammation.}, }
@article {pmid40062548, year = {2025}, author = {Mujica-Alarcon, JF and Gomez-Bolivar, J and Barnes, J and Chronopoulou, M and Ojeda, JJ and Thornton, SF and Rolfe, SA}, title = {The influence of surface materials on microbial biofilm formation in aviation fuel systems.}, journal = {Biofouling}, volume = {}, number = {}, pages = {1-18}, doi = {10.1080/08927014.2025.2471366}, pmid = {40062548}, issn = {1029-2454}, abstract = {The ability of different microbes to form biofilms on materials found in aviation fuel systems was assessed using both individual isolates and complex microbial communities. Biofilm formation by the Gram-negative bacterium, Pseudomonas putida, the fungus Amorphotheca resinae and the yeast, Candida tropicalis, was influenced by material surface properties although this differed between isolates. Biofilm formation was greatest at the fuel-water interface. The Gram-positive bacterium Rhodococcus erythropolis, in contrast, was able to grow on most surfaces. When a subset of materials was exposed to complex microbial communities, the attached microbial community structure was influenced by surface properties and selected for different genera best able to form biofilms on a specific surface. Distinct sub-populations of Pseudomonads were identified, which favoured growth on aluminium or painted surfaces, with a different subpopulation favouring growth on nitrile.}, }
@article {pmid40062463, year = {2025}, author = {Roth, BJ and Khooblall, P and Leelani, N and Suryavanshi, M and Shumaker, A and Werneburg, G and Miller, A and Bajic, P}, title = {Antimicrobial resistance and biofilm formation of penile prosthesis isolates: insights from in-vitro analysis.}, journal = {The journal of sexual medicine}, volume = {}, number = {}, pages = {}, doi = {10.1093/jsxmed/qdaf001}, pmid = {40062463}, issn = {1743-6109}, support = {//Coloplast Corporation/ ; }, abstract = {BACKGROUND: Inflatable penile prostheses (IPPs) have been shown to harbor biofilms in the presence and absence of infection despite exposure to various antimicrobials. Microbes persisting on IPPs following antibiotic exposure have not been adequately studied to assess biofilm formation capacity and antibiotic resistance.<br><br>AIM: In this study, we aimed to assess these properties of microbes obtained from explanted infected and non-infected IPPS using an in vitro model.<br><br>METHODS: 35 bacterial isolates were grown and tested against various single-agent or multiple agent antibiotic regimens including: bacitracin, cefaclor, cefazolin, gentamicin, levofloxacin, trimethoprim-sulfamethoxazole, tobramycin, vancomycin, piperacillin/tazobactam, gentamicin + piperacillin/tazobactam, gentamicin + cefazolin, and gentamicin + vancomycin. Zones of inhibition were averaged for each sample site and species. Statistics were analyzed with Holm's corrected, one-sample t-tests against a null hypothesis of 0. Isolates were also allowed to form biofilms in a 96-well polyvinyl plate and absorbance was tested at 570&#xa0;nm using a microplate reader.<br><br>OUTCOMES: Resistance was determined via clinical guidelines or previously established literature, and the mean and standard deviation of biofilm absorbance values were calculated and normalized to the optical density600 of the bacterial inoculum.<br><br>RESULTS: Every species tested was able to form robust biofilms with the exception of Staphylococcus warneri. As expected, most bacteria were resistant to common perioperative antimicrobial prophylaxis. Gentamicin dual therapy demonstrated somewhat greater efficacy.<br><br>STRENGTHS AND LIMITATIONS: This study examines a broad range of antimicrobials against clinically obtained bacterial isolates. However, not all species and antibiotics tested had standardized breakpoints, requiring the use of surrogate values from the literature. The microbes included in this study and their resistance genes are expectedly biased towards those that survived antibiotic exposure, and thus reflect the types of microbes which might "survive" in vivo exposure following revisional surgery.<br><br>CLINICAL TRANSLATION: Despite exposure to antimicrobials, bacteria isolated during penile prosthesis revision for both infected and non-infected cases exhibit biofilm forming capacity and extensive antibiotic resistance patterns in vitro. These microbes merit further investigation to understand when simple colonization vs re-infection might occur.<br><br>CONCLUSIONS: Although increasing evidence supports the concept that all IPPs harbor biofilms, even in the absence of infection, a deeper understanding of the characteristics of bacteria that survive revisional surgery is warranted. This study demonstrated extensive biofilm forming capabilities, and resistance patterns among bacteria isolated from both non-infected and infected IPP revision surgeries. Further investigation is warranted to determine why some devices become infected while others remain colonized but non-infected.}, }
@article {pmid40060289, year = {2025}, author = {Sarkar, A and Bhattacharjee, S}, title = {Biofilm-mediated bioremediation of xenobiotics and heavy metals: a comprehensive review of microbial ecology, molecular mechanisms, and emerging biotechnological applications.}, journal = {3 Biotech}, volume = {15}, number = {4}, pages = {78}, pmid = {40060289}, issn = {2190-572X}, abstract = {Environmental pollution, driven by rapid industrialization and urbanization, has emerged as a critical global challenge in the twenty-first century. This comprehensive review explores the potential of bacterial biofilms in bioremediation, focusing on their ability to degrade and transform a wide array of pollutants, including heavy metals, persistent organic pollutants (POPs), oil spills, pesticides, and emerging contaminants, such as pharmaceuticals and microplastics. The unique structural and functional characteristics of biofilms, including their extracellular polymeric substance (EPS) matrix, enhanced genetic exchange, and metabolic cooperation, contribute to their superior pollutant degradation capabilities compared to planktonic bacteria. Recent advancements in biofilm-mediated bioremediation include the application of genetically engineered microorganisms, nanoparticle-biofilm interactions, and innovative biofilm reactor designs. The CRISPR-Cas9 system has shown promise in enhancing the degradative capabilities of biofilm-forming bacteria while integrating nanoparticles with bacterial biofilms demonstrates significant improvements in pollutant degradation efficiency. As global pollution rises, biofilm-based bioremediation emerges as a cost-effective and environmentally friendly approach to address diverse contaminants. This review signifies the need for further research to optimize these techniques and harness their full potential in addressing pressing environmental challenges.}, }
@article {pmid40060157, year = {2025}, author = {Jin, HW and Eom, YB}, title = {Potent anti-biofilm properties of plumbagin against fluconazole-resistant Candida auris.}, journal = {Journal of traditional and complementary medicine}, volume = {15}, number = {2}, pages = {140-146}, pmid = {40060157}, issn = {2225-4110}, abstract = {BACKGROUND AND AIM: The escalation of fungal infections is driving an increase in disease and mortality rates. In particular, the emergence of Candida auris (C. auris), which shows powerful resistance to the antifungal drug fluconazole, is becoming a global concern. Furthermore, several biological hurdles need to be overcome by candidate therapeutics because C. auris has the ability to form biofilm. Therefore, this study aimed to investigate the antifungal and anti-biofilm effects of plumbagin, a natural extract, against fluconazole-resistant C. auris (FRCA).<br><br>EXPERIMENTAL PROCEDURE: The minimum inhibitory concentrations (MICs) of fluconazole and plumbagin were determined against clinically isolated C. auris. Inhibition of biofilm formation and eradication effects of plumbagin against FRCA were confirmed through minimum biofilm inhibition concentration (MBIC) and minimum biofilm eradication concentration (MBEC) assays. Additionally, the inhibition of metabolic activity in biofilm cells was verified through quantification by XTT reduction assay and visualization by confocal laser scanning microscopy (CLSM). The relative expression levels of the azole resistant gene ERG11, the efflux pump gene CDR1, and the extracellular matrix gene KRE6, were measured.<br><br>RESULTS AND CONCLUSION: Plumbagin exhibits antifungal efficacy against C. auris and has been shown to effectively inhibit both the formation and eradication of biofilms produced by FRCA. Furthermore, the metabolic activity inhibition in biofilm cells was both quantified and visually observed. The downregulation of all genes (ERG11, CDR1, and KRE6) by plumbagin was confirmed. Taken together, this study demonstrates that plumbagin has antifungal and anti-biofilm efficacy against FRCA, indicating its potential as an alternative to antifungal agents and a valuable resource in combating FRCA infections.}, }
@article {pmid40059987, year = {2025}, author = {Williams, D and Rothberg, D and Kay, W and Nehring, L and Falconer, R and Epperson, RT and Kawaguchi, B and Ardizzone, C and Barnum, B and Ashton, N}, title = {In vivo efficacy of a refillable intrawound drug delivery device in a sheep model of biofilm-compromised open fracture-related infection.}, journal = {Biofilm}, volume = {9}, number = {}, pages = {100262}, pmid = {40059987}, issn = {2590-2075}, abstract = {Open fracture-related infection challenges persist in healthcare. From the time open fractures were defined ∼50 years ago, infection rates have gone essentially unchanged. Contributing factors include compromised vasculature, biofilm, and stalled innovations in treatment and prophylaxis. In this study, we engineered and tested the efficacy of a refillable drug delivery device, the Purgo Pouch (Pouch), that sustains local, high dose intrawound antibiotic concentrations in wound sites. We hypothesized that it would manage biofilm-compromised open fracture-related infection better than clinical standards of care. Therapies were tested in a unique sheep model of long bone open fracture-related infection with compromised tissue and biofilm inocula of methicillin-resistant Staphylococcus aureus. Sheep (n = 5/group) were treated with IV vancomycin (10 days), gentamicin-loaded CaSO4 beads (single application), or the Pouch (10 days) loaded with gentamicin alone or a triple antibiotic combination. At 21 days, sheep were euthanized and microbiological and histological data collected. Results indicated that the Pouch managed infection more effectively, reducing bioburden to <10[5] colony forming units (CFU)/sample, which was statistically significant compared to clinical standards, which failed to reduce bioburden to below 10[5] CFU. The hypothesis was supported. The Pouch received Breakthrough Device Designation by the FDA, is being transitioned toward clinical trials, and is a potential solution to the long-standing problem of open fracture-related infection.}, }
@article {pmid40059312, year = {2025}, author = {Liu, XM and Yu, Y and Jiang, H and Wang, YF and Gao, Y and Xiao, L and Liang, M and Qi, J}, title = {Screening of Anti-Biofilm Compounds From Paeoniae Radix Alba Based on Oral Biofilm Biochromatography.}, journal = {Biomedical chromatography : BMC}, volume = {39}, number = {4}, pages = {e70019}, doi = {10.1002/bmc.70019}, pmid = {40059312}, issn = {1099-0801}, support = {//Qing Lan Project of Jiangsu Province/ ; //Infinitus (China) Company Limited/ ; }, mesh = {*Paeonia/chemistry ; *Biofilms/drug effects ; Chromatography, High Pressure Liquid/methods ; Plant Extracts/pharmacology/chemistry ; Streptococcus mutans/drug effects ; Reproducibility of Results ; Anti-Bacterial Agents/pharmacology/chemistry/isolation &amp; purification ; Humans ; Drugs, Chinese Herbal/pharmacology/chemistry ; Bridged-Ring Compounds ; }, abstract = {Oral biofilms, which are known as dental plaque, are the reason for a wide range of oral and systemic diseases, which contribute to serious health risks. Paeoniae Radix Alba (PRA) is traditionally used as a folk medicine with anti-inflammatory, cardioprotective, and hepatoprotective properties. PRA is currently used in a variety of therapeutic approaches for oral diseases. Nevertheless, its inhibitory effect on oral biofilm formation and the basis for its efficacy have not been clarified. This study intended to screen the potential compounds in PRA that inhibit oral biofilm formation using biochromatography. Two biofilm models based on S. mutans were used to determine the inhibitory effect of PRA on biofilm formation. The extraction of PRA was divided into fractions with different polarity, the active fraction screened, and an HPLC profile constructed for the active fraction. Three potential compounds were screened using targeted oral biofilm extraction, and subsequent validation of the efficacy indicated that albiflorin is the main compound in PRA exerting anti-biofilm activity. Our results have revealed the pharmacological substance basis of PRA in inhibiting the formation of oral biofilm and provide a reference for the further use of PRA in the development of oral health products.}, }
@article {pmid40058924, year = {2025}, author = {Kim, S and Jin, YH and Mah, JH}, title = {Inhibitory effects of garlic, cinnamon, and rosemary on viability, heat resistance, and biofilm formation of Bacillus cereus spores in the broth of a fermented soybean paste stew, Cheonggukjang jjigae.}, journal = {Food research international (Ottawa, Ont.)}, volume = {206}, number = {}, pages = {116078}, doi = {10.1016/j.foodres.2025.116078}, pmid = {40058924}, issn = {1873-7145}, mesh = {*Bacillus cereus/drug effects ; *Garlic/chemistry ; *Biofilms/drug effects ; *Cinnamomum zeylanicum/chemistry ; *Spores, Bacterial/drug effects ; *Rosmarinus/chemistry ; *Plant Extracts/pharmacology ; *Food Microbiology ; Hot Temperature ; Soy Foods/microbiology ; Microbial Viability/drug effects ; Anti-Bacterial Agents/pharmacology ; Fermented Foods/microbiology ; }, abstract = {Foods prepared through heating, including broths, have the potential and risk of survival of Bacillus cereus, which has the ability to form spores and biofilms. This study evaluated the efficacy of various natural products (particularly spices) in mitigating B. cereus contamination in Cheonggukjang jjigae (CJ) broth. The following characteristics of B. cereus were examined: viability of vegetative cells (including other pathogenic bacteria) and planktonic spores, heat resistance of planktonic spores and spores in intact biofilms, and biofilm formation and persistence. In an antimicrobial test to evaluate the inhibitory effects of spice and cruciferous vegetable extracts on B. cereus CH3 vegetative cells, cinnamon, garlic, and rosemary extracts were selected as they have shown significant inhibitory effects, with inhibition zones of 20-29 mm in diameter at the highest concentration tested (160 mg/mL, unless otherwise stated). These spice extracts also exhibited antimicrobial activity against other foodborne pathogens, including Staphylococcus aureus, Listeria monocytogenes, Salmonella Typhimurium, and Escherichia coli O157:H7. Garlic extract showed the greatest inhibitory effect on the viability and heat resistance of planktonic spores of B. cereus CH3, and cinnamon and rosemary extracts exhibited similar effects. Garlic extract reduced B. cereus CH3 spore counts in phosphate buffer solution (PBS) and CJ broth by 20.22 % and 14.08 %, respectively, compared to control (treated with the same ethanol amount instead of the extract), and effectively weakened spore heat resistance, reducing the D100°C-values of planktonic spores of B. cereus CH3 in PBS and CJ broth by 32.89 % and 23.08 %, respectively, compared to control. As for the characteristics related to biofilm, garlic extract showed the highest inhibitory effect on biofilm formation and persistence and heat resistance of spores in intact biofilms, followed by rosemary and cinnamon extracts. All three spice extracts completely inhibited biofilm formation even at the lowest concentration (20 mg/mL) at the early stage of biofilm formation. They completely eradicated biofilm persistence formed in brain heart infusion (BHI) and CJ broth at the highest concentration. A high garlic extract concentration (80 mg/mL) also reduced the D100°C-values of spores in biofilms formed in BHI and CJ broth by 16.34 % and 9.00 %, respectively, compared to control. Taken together, garlic extract was most effective in mitigating B. cereus contamination in a concentration-dependent manner in in vitro-menstrua and CJ broth. This study may provide one of the promising strategies to reduce the risk of B. cereus in soybean stews such as CJ.}, }
@article {pmid40058911, year = {2025}, author = {Yi, Y and Chen, M and Yang, H and Zong, X and Coldea, TE and Zhao, H}, title = {New insights into the role of cellular states, cell-secreted metabolites, and essential nutrients in biofilm formation and menaquinone-7 biosynthesis in Bacillus subtilis natto.}, journal = {Food research international (Ottawa, Ont.)}, volume = {206}, number = {}, pages = {116052}, doi = {10.1016/j.foodres.2025.116052}, pmid = {40058911}, issn = {1873-7145}, mesh = {*Biofilms/growth &amp; development ; *Bacillus subtilis/metabolism/genetics/physiology ; *Vitamin K 2/metabolism/analogs &amp; derivatives ; *Fermentation ; Quorum Sensing ; Gene Expression Regulation, Bacterial ; Protein Hydrolysates/metabolism ; Biomass ; }, abstract = {Menaquinone-7 (MK-7), known for its health benefits, is in high demand across the health and medical fields. Two-stage fermentation strategy can efficiently enhance MK-7 production by Bacillus subtilis natto (B. subtilis natto). However, B. subtilis natto at different growth phases exhibited significant differences in biofilm formation and MK-7 production during the two-stage fermentation, hindering the efficient and stable synthesis of MK-7. Specifically, 0.72 and 0.25 of biofilm biomass values for cells at the early exponential and stationary phases yield MK-7 concentrations of 55.90 and 12.67 mg/L, respectively, with significant variations in the expression levels of quorum sensing, MK-7 synthesis, and biofilm-related genes detected by RT-qPCR. Subsequently, based on experimental procedures involving fermentation supernatant intervention, nutrient supply, and medium renewal, it was found that the deficiency of essential nutrients, particularly low-molecular-weight (< 1 kDa) fractions of soy protein hydrolysate (SPH), was identified as the primary factor of these differences. Additionally, the influence of cell-secreted metabolites, including the downregulation of surfactin and bacilysin expression by 0.61-fold and 0.33-fold, respectively, further exacerbated these effects. Moreover, the increased proportion of depolarized cells and spores, along with reduced intracellular potassium levels in stationary phase cells, was a secondary effect resulting from the two primary causes. Supplementing with ultrafiltration and 75 % ethanol-precipitated fractions of SPH could restore the MK-7 production by 2.35 and 2.05-fold, and biofilm biomass by 2.43 and 2.11-fold, respectively, in B. subtilis natto at the stationary phase. These findings offer a new perspective on the factors influencing biofilm formation and MK-7 production in B. subtilis natto.}, }
@article {pmid40058893, year = {2025}, author = {Zhang, R and Yang, T and Liu, Z and Liao, X and Ahn, J and Sant'Ana, AS and Feng, J and Ding, T}, title = {Inducible adhesion and biofilm formation in Salmonella linked to adaptive fatty acid metabolism.}, journal = {Food research international (Ottawa, Ont.)}, volume = {206}, number = {}, pages = {116006}, doi = {10.1016/j.foodres.2025.116006}, pmid = {40058893}, issn = {1873-7145}, mesh = {*Biofilms/growth &amp; development ; *Salmonella typhimurium/physiology/metabolism/genetics ; *Bacterial Adhesion ; *Fatty Acids/metabolism ; Decanoic Acids/pharmacology/metabolism ; Bacterial Proteins/metabolism/genetics ; Gene Expression Regulation, Bacterial ; Fatty Acid Desaturases/metabolism/genetics ; Energy Metabolism ; Adaptation, Physiological ; Flagella/metabolism/physiology ; Food Microbiology ; }, abstract = {Salmonella is one of the leading causes of foodborne illness, worldwide. The biofilm formation of this bacterium may be caused by its persistence in the food environment. However, the trigger factors and adaptive metabolism in Salmonella for biofilm formation are not fully known. Here, we observed the distinct biofilm formation of S. typhimurium 2220 in response to the presence of medium-chain fatty acids and found that the level of biofilm formation was positively linked to the chain length of the medium-chain fatty acids. Through dynamics analysis of biofilm formation, we discovered that decanoic acid (10‑carbon fatty acid, C10) enhanced the initial attachment of strain 2220 on both biotic and abiotic surfaces, while compromising motility. The attachment was not achieved due to the inhibition of flagella expression but driven by enhanced energy metabolism which was shown as intracellular acidification and elevated ATP level. We found the S. typhimurium 2220 strain could adaptively metabolize fatty acid by enhancing the expression of fadL gene. In summary, Salmonella biofilm formation was inducible by adaptive fatty acid metabolism which resulted in the enhanced attachment. Our results uncovered valuable insights into the physiological alteration of this foodborne pathogen, suggesting the potential biofilm trigger in the food environment. These findings could facilitate the development of a new antibiofilm strategy.}, }
@article {pmid40058248, year = {2025}, author = {Llorente, M and Esteve-Núñez, A and Berenguer, R}, title = {The introduction of surface oxygen groups on fluid-like electrodes enhances biofilm growth of Geobacter sulfurreducens allowing continuous operation.}, journal = {Bioelectrochemistry (Amsterdam, Netherlands)}, volume = {165}, number = {}, pages = {108963}, doi = {10.1016/j.bioelechem.2025.108963}, pmid = {40058248}, issn = {1878-562X}, abstract = {Microbial Electrochemical Fluidized Reactors (ME-FBR) changed the paradigm for growing electroactive bacteria from a biofilm strategy to a planktonic mode, while still performing direct extracellular electron transfer from oxidative metabolism in absence of redox mediators. Glassy carbon was the material selected for growing planktonic Geobacter sulfurreducens in ME-FBR. However, the material was unable to retain cells so applications implying continuous operation have been compromised. In this context, a tailor-made chemical strategy was followed considering the large amount of cytochromes C present on the outermost membrane of bacteria form of the Geobacter genus. In this work, a commercial glassy carbon (GC) was chemically modified with surface oxygen groups (SOGs) mainly carboxylic type with high affinity for heme group of cytochrome C. The functionalized material did conserve the structural and textural features and i) promoted the biofilm formation of Geobacter using acetate as sole carbon and electron donor source, and ii) increased the current density and acetate removal rate in comparison with pristine carbon. Thus, the new material enriched in carboxylic-type SOGs facilitates a-la-carte anchorage of electroactive bacteria to move on from a planktonic-based to a biofilm-based strategy, so ME-FBR operation could be expanded from batch to continuous mode, while electrical current was still possible.}, }
@article {pmid40057915, year = {2025}, author = {Barreto, RA and Ribeiro, ER and de Menezes, CLA and Zaiter, MA and Boscolo, M and da Silva, R and Gomes, E and da Silva, RR}, title = {Production and Potential Application of an Alkaline Serine Peptidase from Myceliophtora heterothallica for Biofilm Removal.}, journal = {Current microbiology}, volume = {82}, number = {4}, pages = {179}, pmid = {40057915}, issn = {1432-0991}, mesh = {*Biofilms/growth &amp; development ; Hydrogen-Ion Concentration ; *Enzyme Stability ; *Temperature ; Fungal Proteins/metabolism/genetics/chemistry ; Serine Proteases/metabolism/chemistry/genetics/isolation &amp; purification ; Caseins/metabolism ; Substrate Specificity ; Fermentation ; }, abstract = {Peptidases belong to the hydrolase class (EC 3.4) and catalyze the hydrolysis of peptide bonds. These enzymes, particularly those of microbial origin, have significant commercial importance because of their ease of production and wide range of industrial applications. The expansion of this market justifies the search for new enzymes with different substrate specificities, increased thermostability, and reduced production costs. In this study, we investigated the production of peptidases by the thermophilic fungus Myceliophtora heterothallica F2.1.4, via submerged culture and functional biochemical characterization of the produced enzymes. Among the conditions assessed, the fungus exhibited the highest peptidase production after 48 h of growth in medium supplemented with 0.5% casein. Regarding the functional properties of the produced enzymes, higher caseinolytic activity was observed under alkaline pH (9.5-10.5) and a temperature range of 45-50 °C for the pure enzyme (molecular mass estimated at 31 kDa) and 50-55 °C for the fermentative extract. Peptidases from the fermentative extract and the pure enzyme retained more than 60% of their activities for 1 h at 50 °C and were stable over a wide pH range (5.5-10.5). The proteolytic activity was primarily suppressed by PMSF and copper (II) and positively modulated by cobalt, showing an increase of up to 58% at 15 mM of this ion. The fermentative extract from the culture was effective in removing Staphylococcus aureus and Candida albicans biofilms with dispersal rates of 25% and 35%, respectively.}, }
@article {pmid40057552, year = {2025}, author = {Jiang, Q and Xu, M and Chen, H and Zhang, Y and Sun, Y and Tao, L and Wang, Z and Yang, D}, title = {V-ATPase contributes to the cariogenicity of Candida albicans- Streptococcus mutans biofilm.}, journal = {NPJ biofilms and microbiomes}, volume = {11}, number = {1}, pages = {41}, pmid = {40057552}, issn = {2055-5008}, support = {32270888//National Natural Science Foundation of China (National Science Foundation of China)/ ; 82301055//National Natural Science Foundation of China (National Science Foundation of China)/ ; 32370202//National Natural Science Foundation of China (National Science Foundation of China)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Candida albicans/genetics/physiology ; *Streptococcus mutans/genetics ; *Dental Caries/microbiology ; *Vacuolar Proton-Translocating ATPases/genetics/metabolism ; Humans ; Child ; Gene Expression Profiling ; Virulence ; Fungal Proteins/genetics/metabolism ; Gene Expression Regulation, Fungal ; }, abstract = {The interaction between Candida albicans and Streptococcus mutans plays an important role in the progression of dental caries. The vacuolar proton pump (V-ATPase) is a vital enzyme regulating the growth and virulence of C. albicans, which is a potential target for caries prevention. However, the effect of V-ATPase on the cariogenicity of C. albicans-S. mutans biofilm remains to be explored. In this study, the detection rate of C. albicans in caries-active (group CA) (22.03%) was significantly higher than that in caries-free (group CF) children (8.00%), and the expression of V-ATPase related genes were higher in group CA. Then, the higher expressed V-ATPase coding genes VMA3, VMA4 and VMA11 in CA group were knocked out. Compared with the wild type SC5314, the mutants showed slower growth rate, inhibited hyphal growth, and defective integrity of cell wall. The biofilm biomass and extracellular polysaccharide (EPS) production of dual biofilm were significantly reduced, and the biofilm structure was impacted. Transcriptome analysis indicated that V-ATPase participated in various metabolisms and biosynthesis pathways of C. albicans, and influenced EPS metabolism of S. mutans. Finally, compared with the positive control, the caries severity, the biomass and EPS production of dental plaque were significantly reduced after deletion of VMA3, VMA4 and VMA11 in vivo. This study revealed for the first time the regulating effect of V-ATPase on the cariogenicity of C. albicans-S. mutans biofilm and its potential mechanisms. The results may provide basis for new strategies of ecological prevention and treatment of dental caries.}, }
@article {pmid40056461, year = {2025}, author = {Wang, L and Zhou, J and Xiong, J and Hu, T and Xia, Q}, title = {Denitrification efficiency and biofilm community succession in a bidirectional alternating influent biofilter.}, journal = {Environmental technology}, volume = {}, number = {}, pages = {1-15}, doi = {10.1080/09593330.2024.2448764}, pmid = {40056461}, issn = {1479-487X}, abstract = {Biofilters are widely used for nitrogen removal in wastewater treatment. This study developed a bidirectional alternating-influent biofilter to reduce clogging and enhance nitrogen removal. Alternating influent utilized biofilm on the media as a denitrification carbon source. With initial ammonium, nitrate, and total nitrogen concentrations of 8.49±0.30, 12.52±0.20, and 19.89±0.79 mg/L, the forward influent achieved ammonium, nitrate, and total nitrogen removal efficiencies of 81.6%, 66.8%, and 71.2%, increasing by 13.3%, 3.0%, and 4.8% at the effluent. Reverse influent further boosted nitrate and total nitrogen removal by 14.0% and 5.5%. The natural DO gradient under conventional influent conditions was simulated, and the nitrogen removal mechanism and treatment effect, mainly nitrification and denitrification, were discussed. Microbial analysis showed that endogenous carbon in the biofilm, derived from decaying cells and EPS, reduced clogging risk. Significant changes in bacterial count, EPS content, and microbial abundance were observed across influent directions, with Proteobacteria, Bacteroidetes, and Pseudomonas increasing under reverse flow. These results indicate that bidirectional alternating influent can significantly improve nitrogen removal and reduce clogging, offering an effective optimization for wastewater treatment.}, }
@article {pmid40056229, year = {2025}, author = {Ding, ZW and Xu, KZ and Dar, OI and Yin, LJ and Wang, YJ and Liao, YT and Wang, P and Jia, AQ}, title = {Deferiprone inhibits virulence and biofilm formation in Burkholderia cenocepacia.}, journal = {Medical microbiology and immunology}, volume = {214}, number = {1}, pages = {15}, pmid = {40056229}, issn = {1432-1831}, support = {Qhyb2023-71, SA2400003318//Innovative Research Projects for Postgraduates in Hainan Province/ ; HNDZDC-2024-3, HXY2024-026RR//Hainan Province Clinical Medical Center, Hainan Financial Public Welfare Project: Ground Substrate Survey to Hainan Cultivated Land (2024)/ ; 82160664//National Natural Science Foundation of China/ ; ZDYF2024SHFZ103//Hainan Province Science and Technology Special Fund/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Burkholderia cenocepacia/drug effects ; *Quorum Sensing/drug effects ; Virulence/drug effects ; Animals ; *Deferiprone/pharmacology ; *Microbial Sensitivity Tests ; *Molecular Docking Simulation ; Bacterial Proteins/metabolism/genetics ; Anti-Bacterial Agents/pharmacology ; Moths/microbiology/drug effects ; Burkholderia Infections/drug therapy/microbiology ; Tandem Mass Spectrometry ; Disease Models, Animal ; Repressor Proteins ; }, abstract = {Burkholderia cenocepacia, an opportunistic pathogen, poses a significant threat to human health, necessitating the discovery of effective quorum sensing inhibitors (QSIs). In this study, the quorum sensing inhibitory effects of deferiprone (DFP) on the B. cenocepacia 162,638 were validated. Notably, DFP demonstrated an ability to inhibit and disrupt bacterial biofilms, reducing biofilm formation by 44.59% at 1/4 MIC (minimum inhibitory concentration) and 24.32% at 1/8 MIC concentrations. The study also investigated DFP's impact on motility, virulence, and QS signal levels. LC-MS/MS analysis showed a gradual reduction in the QS molecule C6-HSL as DFP concentrations increased. Additionally, DFP's non-hemolytic properties and safety profile, as verified in Galleria mellonella infection models, highlighted its biocompatibility. RT-qPCR results further indicated that DFP downregulated QS-related gene expression, particularly those involved in ferric uptake regulation protein (Fur). Molecular docking studies identified Fur as a key target for DFP's inhibitory action. Collectively, DFP was shown as a potential QSI with practical applications for controlling B. cenocepacia infections.}, }
@article {pmid40055321, year = {2025}, author = {Cai, YM and Hong, F and De Craemer, A and Malone, JG and Crabbé, A and Coenye, T}, title = {Echinacoside reduces intracellular c-di-GMP levels and potentiates tobramycin activity against Pseudomonas aeruginosa biofilm aggregates.}, journal = {NPJ biofilms and microbiomes}, volume = {11}, number = {1}, pages = {40}, pmid = {40055321}, issn = {2055-5008}, support = {101023767//Marie Sk&#x142;odowska-Curie Standard European Fellowships/ ; 2021310031006618//National Advanced Functional Fiber Innovation Center/ ; BB/X010996/1/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom ; }, mesh = {*Pseudomonas aeruginosa/drug effects/genetics/physiology ; *Biofilms/drug effects/growth &amp; development ; *Cyclic GMP/analogs &amp; derivatives/metabolism ; *Tobramycin/pharmacology ; Animals ; *Anti-Bacterial Agents/pharmacology ; *Glycosides/pharmacology/metabolism ; Mice ; *Phosphorus-Oxygen Lyases/metabolism/genetics ; *Drug Synergism ; *Pseudomonas Infections/microbiology/drug therapy ; Humans ; Sputum/microbiology ; Bacterial Proteins/genetics/metabolism ; Cystic Fibrosis/microbiology ; Gene Expression Regulation, Bacterial/drug effects ; Microbial Sensitivity Tests ; Escherichia coli Proteins ; }, abstract = {Cyclic diguanylate (c-di-GMP) is a central biofilm regulator in Pseudomonas aeruginosa, where increased intracellular levels promote biofilm formation and antibiotic tolerance. Targeting the c-di-GMP network may be a promising anti-biofilm approach, but most strategies studied so far aimed at eliminating surface-attached biofilms, while in vivo P. aeruginosa biofilms often occur as suspended aggregates. Here, the expression profile of c-di-GMP metabolism-related genes was analysed among 32 P. aeruginosa strains grown as aggregates in synthetic cystic fibrosis sputum. The diguanylate cyclase SiaD proved essential for auto-aggregation under in vivo-like conditions. Virtual screening predicted a high binding affinity of echinacoside towards the active site of SiaD. Echinacoside reduced c-di-GMP levels and aggregate sizes and potentiated tobramycin activity against aggregates in >80% of strains tested. This synergism was also observed in P. aeruginosa-infected 3-D alveolar epithelial cells and murine lungs, demonstrating echinacoside's potential as an adjunctive therapy for recalcitrant P. aeruginosa infections.}, }
@article {pmid40055277, year = {2025}, author = {Ali, DS and Vazifehmand, R and Malik, MA and Rukayadi, Y and Radu, S and Mirpour, M and Nor-Khaizura, MAR}, title = {Molecular profiling and bioinformatics approaches of biofilm formation in ionizing radiation-resistant Bacillus subtilis, isolated from geothermal spring in Ramsar, the North of Iran.}, journal = {World journal of microbiology &amp; biotechnology}, volume = {41}, number = {3}, pages = {97}, pmid = {40055277}, issn = {1573-0972}, support = {Insentif Putra Siswazah, GP-IPS/2016/9488300//Universiti Putra Malaysia/ ; Insentif Putra Siswazah, GP-IPS/2016/9488300//Universiti Putra Malaysia/ ; }, mesh = {*Biofilms/growth &amp; development/radiation effects ; *Bacillus subtilis/genetics/radiation effects/physiology ; *Bacterial Proteins/genetics/metabolism ; *Hot Springs/microbiology ; *Gene Expression Regulation, Bacterial ; Iran ; *Operon ; *Computational Biology ; Radiation, Ionizing ; Gene Expression Profiling ; Genetic Variation ; Nucleic Acid Conformation ; }, abstract = {Biofilm formation and its molecular signaling in bacteria resistant to ionizing radiation is not fully understood. This study aimed to investigate the genetic variations and gene expression of biofilm in an ionizing radiation-resistant Bacillus subtilis in Ramsar. Direct sequencing and quantitative PCR were applied to determine nucleotide variations and gene expression profiles of tapA-sipW-tasA, sinR, sinI, ccpA, epsA-O, spoOB, spoOA, slrA, slrR, ymcA and abrB genes. RNAsnp-RNAfold and Phyre2 and the Swiss Model webserver were used to analyze the structural mRNA and protein respectively. At the molecular level, the tapA-sipW-tasA operon was significantly overexpressed and the expression of ccpA and slrR was significantly downregulated. The thermodynamic and ensemble diversity ratio of the tapA (G>C) gene showed the largest changes in RNA secondary structure. In addition, the largest protein pocket belonged to tapA (148.6 A[03]) compared to the normal structure (121.1 A[03]). A non-radiation Bacillus subtilis was served as a control group. These results support the hypothesis that the induction of robust biofilm formation is through the (tapA) operon signal in ionizing radiation-resistant B. subtilis and that genetic variation in tapA (G>C) was the major gene associated with diversity in robust biofilm formation.}, }
@article {pmid40057454, year = {2025}, author = {Sathishkumar, K and Kannan, VR and Alsalhi, MS and Rajasekar, A and Devanesan, S and Narenkumar, J and Kim, W and Liu, X}, title = {Retraction notice to "Intimately coupled gC3N4 photocatalysis and mixed culture biofilm enhanced detoxification of sulfamethoxazole: Elucidating degradation mechanism and toxicity assessment" [Environ. Res. 214-P1 (2022) 113824].}, journal = {Environmental research}, volume = {}, number = {}, pages = {121124}, doi = {10.1016/j.envres.2025.121124}, pmid = {40057454}, issn = {1096-0953}, }
@article {pmid40056594, year = {2025}, author = {Zhang, H and Zhang, Y and Li, L and Huang, S and Ma, W and Xu, B and Ng, HY and Kim, DH and Kang, S and Shi, X}, title = {An innovative high-rate biofilm-based process: Biopolymer production and recovery from wastewater organic pollutants.}, journal = {Journal of environmental management}, volume = {379}, number = {}, pages = {124800}, doi = {10.1016/j.jenvman.2025.124800}, pmid = {40056594}, issn = {1095-8630}, abstract = {In this study, a novel high-rate moving bed biofilm reactor (MBBR) was constructed to enhance wastewater COD bio-conversion and biopolymer recovery with a hydraulic retention time (HRT) of 1.0 h and an organic loading rate (OLR) of 4.8 kg COD·m[-3]·d[-1]. A superior specific COD reduction rate of 4.1 kg COD·m[-3]·d[-1] was obtained. The settleability analyses showed that within a settling time of 30 min, a low effluent suspended solids (SS) concentration (40.6 mg/L) with a high biomass recovery rate (83.3%) was achieved. From the recovered biomass, a remarkably higher alginate-like exopolymer (ALE) yield (274.2-385.1 mg/g VSS) was extracted as compared with seeding sludge (148.3 mg/g VSS). In addition, high protein/polysaccharide ratios of 8.5-12.4 were revealed owing to the short HRT condition. Moreover, key functional genes involving classic ALE synthesis were fully detected in such mixed-cultured bioprocess through metagenomic sequencing. Overall, this study offers a proof of concept that bio-refinery of organics into value-added biopolymers could provide a promising direction for the transformation of wastewater treatment plants from energy/resource-consuming factories to resource-recovery factories.}, }
@article {pmid40053510, year = {2025}, author = {Zhai, J and Nie, L and Tian, J and He, Y and Gu, Y}, title = {Stress resistance of the biofilm and planktonic forms of Lactobacillus delbrueckii in adverse environments.}, journal = {Letters in applied microbiology}, volume = {}, number = {}, pages = {}, doi = {10.1093/lambio/ovaf031}, pmid = {40053510}, issn = {1472-765X}, abstract = {Biofilm and planktonic forms are different kinds of self-protection mechanisms in microorganisms for resistance to adverse environments. The research explored the physicochemical properties, antimicrobial and antioxidant activities of Lactobacillus delbrueckii (L. delbrueckii) 5E, focusing on the biofilm's stress tolerance. L. delbrueckii 5E's high lactic acid production (709.1 g·L-1) enhances its antimicrobial activity, which is pH-dependent and decreases when the supernatant is adjusted to pH 6.5. The cell-free fermentation supernatant, bacterial suspension, and cell-free extract of L. delbrueckii 5E showed significant scavenging activity against DPPH, hydroxyl, and superoxide anion radicals. L. delbrueckii 5E formed biofilms with a bacterial count of 9.00 × 106 CFU·mL-1 on polyacrylonitrile electrospun membranes. Stress tolerance tests indicated that the biofilm form of L. delbrueckii 5E exhibited superior survival under high temperatures, osmotic pressures, bile salts, potassium sorbate, and H2O2 exposure. The biofilm consistently released free bacteria, maintaining a stable total colony count of 106 CFU·mL-1. The remarkable antibacterial and antioxidant properties of L. delbrueckii 5E, along with its resilience to harsh environments, establish its potential for applications in the food industry.}, }
@article {pmid40051528, year = {2025}, author = {Wei, G and Xiao, T and Xi, Y and Ju, R}, title = {A macrophage-like biomimetic nanoparticle with high-efficiency biofilm disruption and innate immunity activation for implant-related infection therapy.}, journal = {Materials today. Bio}, volume = {31}, number = {}, pages = {101575}, pmid = {40051528}, issn = {2590-0064}, abstract = {The innate immune system's inactivation and microbial biofilm-induced antibiotic resistance are the main causes of implant-associated infections (IAIs), which frequently result in implant surgical failure. Refractory recolonization is the consequence of standard therapies that are unable to consistently suppress escaping planktonic bacteria from biofilm, thereby enabling IAIs to thrive. Here, we specifically designed a macrophage-like biomimetic nanoparticle (F/R@PM) for a biofilm microenvironment (BME), which was fabricated by coating the cell membrane derived from macrophage onto poly (lactic-co-glycolic acid) (PLGA) namoparticles (NPs) loaded with FOT (NO donor) and R837 (TLR7 agonist). After injecting F/R@PM into mice with implant-associated infections, it was able to selectively target macrophages through macrophage membrane proteins on its surface and effectively release FOT and R837. Then, FOT that spreads outside the cell could react with glutathione (GSH) in the BEM to rapidly produce a large amount of NO inside biofilms to destroy the biofilm and kill bacteria. At the same time, R837 would encourage macrophages to scavenge planktonic bacteria that had escaped biofilm disintegration through improved phagocytosis. Overall, this work shows that NO treatment and immunotherapy together have promising potential for the long-term and efficient control and eradication of IAIs.}, }
@article {pmid40051112, year = {2022}, author = {Yamada, K and Fukushima, T and Freguia, S}, title = {Coke-oven wastewater treatment in a dual-chamber microbial fuel cell with thiocyanate-degrading biofilm enriched at the air cathode.}, journal = {Water science and technology : a journal of the International Association on Water Pollution Research}, volume = {85}, number = {7}, pages = {2254-2264}, pmid = {40051112}, issn = {0273-1223}, abstract = {Coke-oven wastewater is usually treated with the activated sludge process, which requires large amounts of electrical energy for aeration and sludge disposal. A more sustainable treatment is strongly required. Recently, microbial fuel cells (MFCs) are focused as a technology for the production of electricity from wastewaters with simultaneous removal of organic matter. However, no MFC has been reported that can remove phenol, thiosulfate and thiocyanate simultaneously without aeration. Phenol can generally be removed well, whereas thiocyanate is relatively difficult to degrade. In this study, a dual-chamber MFC (D-MFC) was designed and equipped with a thiocyanate-degrading biofilm enriched on an air cathode. The D-MFC degraded phenol and thiosulfate in the anode chamber at the rate of 104 and 331 mg/L/day, respectively and subsequently degraded thiocyanate in the cathode chamber at the rate of 250 mg/L/day. The D-MFC showed high thiocyanate degradation rate. This suggests that pre-enrichment could accelerate thiocyanate degradation in MFC. In addition, thiocyanate degradation was not inhibited by phenol as thiocyanate was removed in the cathode chamber after phenol was removed in the anode chamber. This study demonstrated the feasibility of treating coke-oven wastewater by a D-MFC with a thiocyanate-degrading biofilm enriched at the air cathode.}, }
@article {pmid40050626, year = {2025}, author = {Rana, ML and Ullah, MA and Hoque, MN and Hassan, J and Siddique, MP and Rahman, MT}, title = {Preliminary survey of biofilm forming, antibiotic resistant Escherichia coli in fishes from land based aquaculture systems and open water bodies in Bangladesh.}, journal = {Scientific reports}, volume = {15}, number = {1}, pages = {7811}, pmid = {40050626}, issn = {2045-2322}, mesh = {*Biofilms/drug effects/growth &amp; development ; Animals ; *Escherichia coli/genetics/isolation &amp; purification/drug effects ; Bangladesh/epidemiology ; *Aquaculture ; *Anti-Bacterial Agents/pharmacology ; *Fishes/microbiology ; Microbial Sensitivity Tests ; Drug Resistance, Bacterial/genetics ; Escherichia coli Infections/microbiology/veterinary/epidemiology ; Drug Resistance, Multiple, Bacterial/genetics ; Water Microbiology ; Fish Diseases/microbiology ; }, abstract = {The emergence and spread of multidrug-resistant pathogens, such as Escherichia coli, present major global public health challenges. This study aimed to investigate the prevalence, antibiotic resistance patterns, biofilm production, and the presence of antibiotic resistance genes (ARGs) and biofilm-forming genes in E. coli isolated from fish in open-body water (wild) sources and land-based aquaculture (cultured) systems in Mymensingh, Bangladesh. We collected 130 fish (Koi: Anabas testudineus and Shing: Heteropneustes fossilis) among which 70 were from wild sources and 60 from cultured systems. We screened 116 probable E. coli isolates through selective culture, Gram-staining, and biochemical tests. Using malB gene-specific PCR, we confirmed 87 isolates (67.0%) as E. coli. Cultured fish had a higher prevalence (70.0%) compared to wild fish (64.0%). Biofilm formation was detected in 20.0% E. coli by Congo red agar tests. However, crystal violet assays revealed that 70.0% of E. coli from cultured fish produced biofilm, compared to 20.0% from wild fish, with 7.0% of cultured fish isolates showing strong biofilm production. Antibiotic resistance profiling showed that 100.0% E. coli isolates were resistant to ampicillin and ceftazidime, beta-lactamase-producing antibiotics. Resistance patterns varied by source, with nearly 97.0% of E. coli from cultured fish being multidrug-resistant (MDR), compared to 60.0% in wild fish. E. coli from cultured fish were identified as potential reservoirs of ARGs such as blaTEM (83.0%), blaSHV (81.0%), blaCTX (78.57%), and the biofilm forming gene fimC (100.0%). Significant associations were observed for blaTEM (p = 0.033), blaSHV (p = 0.038), and fimC (p = 0.005). These findings highlight the need for monitoring β-lactamase-resistant and biofilm-forming E. coli in both wild and cultured fish in Bangladesh due to their potential threat to public health and animal populations.}, }
@article {pmid40049472, year = {2025}, author = {Pushpakaran, A and Gupta, A and Katdare, S and Ashtam, A and Pratap, V and Bharatam, PV and Panda, D}, title = {Enhancement of GTP hydrolysis and inhibition of polymerization of the cell division protein FtsZ by an N-heterocyclic imine derivative impede growth and biofilm formation in Streptococcus pneumoniae.}, journal = {International journal of biological macromolecules}, volume = {}, number = {}, pages = {141762}, doi = {10.1016/j.ijbiomac.2025.141762}, pmid = {40049472}, issn = {1879-0003}, abstract = {FtsZ polymerizes to form a cytokinetic Z-ring at the mid-cell and coordinates the partitioning of a bacterial cell. Its crucial role in bacterial cell division and widely conserved nature makes it a promising target for antibacterial drugs. Streptococcus pneumoniae, a prevalent respiratory pathogen, is acquiring antimicrobial resistance at an alarming rate, highlighting the need for developing potent anti-pneumococcal agents. In this work, we identified the FtsZ-inhibitory property of an N- heterocyclic imine derivative, 3-methyl-N-(3-(p-tolyl)-1,3-thiazetidin-2-ylidene)amino)-6-trifluoromethoxy)-benzo[d]thiazolium-trifluoromethane-sulfonate (TTMB). TTMB inhibited the growth of S. pneumoniae, Staphylococcus aureus, Bacillus subtilis, Vibrio cholerae, Staphylococcus saprophyticus, and Mycobacterium smegmatis, indicating its broad-spectrum antibacterial activity. Further, TTMB inhibited biofilm formation by the pathogenic strain of S. pneumoniae. TTMB destroyed the Z-ring in S. pneumoniae and B. subtilis. The compound binds to purified FtsZ, increases the GTPase activity of FtsZ, and inhibits FtsZ assembly. FtsZ forms short and thin polymers and aggregates in the presence of TTMB. Importantly, TTMB exhibited low cytotoxicity to mammalian cells and did not inhibit tubulin polymerization or the activity of metabolic enzymes like alkaline phosphatase and alcohol dehydrogenase, suggesting its safety for mammalian systems. The dual-acting property of TTMB, targeting both planktonic and biofilm-forming S. pneumoniae, makes it a promising antibacterial agent.}, }
@article {pmid40048555, year = {2025}, author = {Nahum, Y and Cerrone, A and Nerenberg, R}, title = {Impact of Low-Frequency Ultrasound on Physical Properties and Antibiotic Susceptibility of a Mucoid Biofilm.}, journal = {Langmuir : the ACS journal of surfaces and colloids}, volume = {}, number = {}, pages = {}, doi = {10.1021/acs.langmuir.4c04840}, pmid = {40048555}, issn = {1520-5827}, abstract = {Pseudomonas aeruginosa (P. aeruginosa) is a pathogen commonly associated with lung infections in cystic fibrosis (CF) patients, often developing a mucoid phenotype that overproduces alginate, a major component of the biofilm's extracellular polymeric substances (EPS) matrix, increasing tolerance to antibiotics. Past studies have shown that low-frequency ultrasound (LFU) increases the antibiotic susceptibility of P. aeruginosa in biofilms, but its effects on mucoid strains are unknown. In this study, we assessed the combined application of LFU and antibiotics on P. aeruginosa FRD1, a mucoid strain, and compared it to nonmucoid P. aeruginosa PAO1 biofilms. The mucoid biofilm exhibited greater stiffness, thickness, and density, with polysaccharides (likely alginate) comprising over 70% of the EPS matrix. Although LFU application led to a 50% increase in biofilm creep compliance, no synergistic effect was observed with tobramycin. However, the same LFU treatment significantly improved ciprofloxacin susceptibility. We implemented a one-dimensional model that estimated a 25-fold increase in the diffusion coefficient for ciprofloxacin following LFU, though higher intensities were needed to induce comparable effects in diffusivity and mechanical properties compared to the nonmucoid biofilm. The model also suggested that tobramycin likely sorbed to alginate, hindering diffusion to the biofilm interior, thereby reducing its inactivation efficiency. Our findings suggest that LFU can impact antibiotic diffusion through the biofilm and mechanical properties but not necessarily overcome antibiotic interactions with the EPS matrix. Additionally, variations in EPS matrix composition may require different LFU intensities for effective outcomes. These results may have significant implications for potential clinical applications, especially for CF patients.}, }
@article {pmid40047947, year = {2025}, author = {Wang, W and Zhong, Q and Huang, X}, title = {Antibacterial and anti-biofilm activities of Derazantinib (ARQ-087) against Staphylococcus aureus.}, journal = {Archives of microbiology}, volume = {207}, number = {4}, pages = {78}, pmid = {40047947}, issn = {1432-072X}, support = {202140032//The Science and Technology Project of Jiangxi Health Commission/ ; }, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology ; *Methicillin-Resistant Staphylococcus aureus/drug effects ; *Microbial Sensitivity Tests ; Animals ; *Staphylococcal Infections/drug therapy/microbiology ; Staphylococcus aureus/drug effects/physiology ; Humans ; Moths/microbiology/drug effects ; Reactive Oxygen Species/metabolism ; Larva/drug effects/microbiology ; }, abstract = {The global rise of multidrug-resistant pathogens, particularly methicillin-resistant Staphylococcus aureus (MRSA), represents a critical public health challenge. This study evaluates the antibacterial and anti-biofilm activities of Derazantinib (ARQ-087) against S. aureus. ARQ-087 exhibited minimum inhibitory concentration (MIC) values ranging from 4 to 16 µM against S. aureus reference laboratory strains and diverse clinical MRSA isolates, demonstrating strong antibacterial activity with minimal resistance development. Time-kill assays demonstrated a concentration- and time-dependent reduction in bacterial viability. Crystal violet staining assays revealed that ARQ-087 significantly inhibited MRSA biofilm formation in a dose-dependent manner. Additionally, ARQ-087 exhibited strong anti-biofilm activity against pre-formed biofilms, as shown by colony counts and confocal laser scanning microscopy, which indicated extensive biofilm disruption and bacterial cell death. Mechanistic studies revealed that ARQ-087 disrupts bacterial membrane integrity, as evidenced by SYTOX Green and DISC3(5) fluorescence assays, while inducing intracellular ATP depletion and reactive oxygen species generation, contributing to bacterial death. ARQ-087 also displayed negligible hemolytic activity and no acute toxicity observed in a Galleria mellonella infection model. In this model, ARQ-087 prolonged the survival of larvae infected with S. aureus. These findings highlight ARQ-087 as a promising therapeutic candidate for treating MRSA infections and biofilm-associated diseases. Further preclinical studies are needed to confirm its potential for clinical application.}, }
@article {pmid40043625, year = {2025}, author = {Cazals, M and Bédard, E and Guerra Maldonado, JF and Prévost, M}, title = {What happens in your water system? Impact of materials, temperature, stagnation and chlorination on water quality and biofilm formation.}, journal = {Chemosphere}, volume = {376}, number = {}, pages = {144248}, doi = {10.1016/j.chemosphere.2025.144248}, pmid = {40043625}, issn = {1879-1298}, abstract = {Building water distribution system materials are diverse and their impact on water quality depends on nutrients, stagnation, and temperature. The main objective was to investigate the interplay between material type, temperature and stagnation on water quality and biofilm formation potential. CDC biofilm reactors were used to compare concentrations of metals, total (DOC) and biodegradable (BDOC) dissolved organic carbon, and total and viable cells densities in water and biofilms in contact with coupons of 6 materials: polypropylene (PP), polyvinyl chloride (PVC), ethylene propylene diene monomer (EPDM), cross-linked polyethylene (PEX), stainless steel (SS) and copper (Cu). All materials were colonized by bacteria, with denser biofilm observed on EPDM > PP > PVC > PEX > Cu - SS. Copper and EPDM reactors showed different dynamics of accumulation and release of Cu and Pb, with bulk Pb concentrations exceeding 5 μg/L. Increasing temperatures from 25 °C to 40, 55 and 60 °C resulted in an increase by at least a factor 2 of DOC and BDOC, a temporary decrease in cell viability (%) and contrasting trends for suspended total bacteria (up to 1.4-log). Biofilm densities remained lower for all reactors after two months of constant heating at 40 °C, even further for copper reactors heated to 55 °C (2.5-log) and 60 °C (2.7-log). A 4-week stagnation at room temperature promoted total bacteria recovery in water and biofilm for all materials except copper. Extending stagnation to 6 months (COVID-19 shutdown) further increased total bacteria and the viable fraction in water, except in copper reactors.}, }
@article {pmid40043581, year = {2025}, author = {Yao, J and Li, Y and An, L and Wang, P and Liu, D and Ma, J and Wang, A and Wang, W}, title = {Tolerant and highly-permeable membrane aerated biofilm reactor enabled by selective armored membrane.}, journal = {Water research}, volume = {278}, number = {}, pages = {123337}, doi = {10.1016/j.watres.2025.123337}, pmid = {40043581}, issn = {1879-2448}, abstract = {Membrane aerated biofilm reactor (MABR) is a promising technology for dramatically reducing aeration energy consumption in wastewater treatment. However, the crucial membranes, including microporous hydrophobic membranes and dense membranes, are intolerant to fouling and possess high oxygen transfer resistance respectively, hindering their application potential. Herein, we developed a tolerant and highly-permeable membrane aerated biofilm reactor (THMABR) with a selective armor layer on the membrane to support the biofilm. The selective permeability of the selective armor layer enabled oxygen transfer efficiently and prevented interference by water, surfactant and microbial extracellular polymers. Besides, the composite of the 5 μm selective armor layer and microporous support significantly shortened the distance for solution-diffusion, reducing the transmembrane energy barrier of oxygen molecules. The THMABR's excellent and stable oxygen permeability solved the oxygen substrate concentration's limitation on oxidation rate, enabling functional bacteria to possess a higher oxidation potential and more abundant ecological niche. Based on the novel design, oxygen selective armor membrane (OSAM) performed notably higher oxygen transfer rates (9.61 gO2·m[-2]d[-1]) compared to the fouled microporous hydrophobic membrane (3.31 gO2·m[-2]d[-1]) and the dense membrane (4.04 gO2·m[-2]d[-1]). Besides, the OSAM exhibited more stable fouling resistance to water infiltration and pollutant intrusion compared to the microporous hydrophobic membrane after surfactant pretreatment. Municipal wastewater treatment tests further confirmed that the novel membrane support-selective armored layer-biofilm structure of THMABR can high-efficiently remove nitrogen. The structural characteristics, mechanisms of fouling resistance and oxygen transfer, as well as wastewater treatment performance of the THMABR and OSAM are discussed in detail. This work introduces a new design concept to overcome the bottleneck of traditional MABRs involving the disunity of tolerance and permeability, being expected to support the low-carbon and stable operation of wastewater biological treatment.}, }
@article {pmid40042559, year = {2025}, author = {Rawat, N and Sheoran, S and Khan, J and Khan, R and Alzobaidi, N and Alhalmi, A}, title = {Different aspects of Pseudomonas aeruginosa biofilm: an in-depth analysis from formation to detection.}, journal = {Naunyn-Schmiedeberg's archives of pharmacology}, volume = {}, number = {}, pages = {}, pmid = {40042559}, issn = {1432-1912}, abstract = {Planktonic pathogens pose a significant threat to the global community, especially as they develop into microbial biofilms. Pseudomonas aeruginosa, a gram-negative bacillus, is notorious for causing nosocomial infections and can easily transform into a multidrug-resistant form, particularly within biofilms. This transformation leads to chronic infections in immunocompromised individuals, increasing morbidity and mortality rates worldwide. P. aeruginosa uses biofilms to survive, becoming robust and evading the host's immune protection system. Biofilms also shield microorganisms from antibiotics, rendering them drug-resistant and causing treatment failures. P. aeruginosa biofilms are often associated with device-related infections, as indwelling medical devices (IMDs) serve as breeding grounds for microbial biofilm growth. The ubiquitous presence of P. aeruginosa on both living and abiotic surfaces makes it an excellent model for studying biofilms. The virulence factors of P. aeruginosa, such as lipopolysaccharides, pili, flagella, adhesins, and exopolysaccharides, facilitate disease progression and contribute to biofilm development and maturation. This review focuses on analyzing the characteristics of P. aeruginosa biofilms, including antimicrobial resistance and gene regulation. Methods for detecting biofilms are also briefly described. Additionally, this review provides a comprehensive exploration of the most effective methods for preventing and controlling microbial biofilms, particularly those formed by P. aeruginosa. This study aims to inspire future research and the development of innovative technologies to resist microbial adherence, colonization, and biofilm formation.}, }
@article {pmid40041091, year = {2025}, author = {Campos, JV and Pontes, JTC and Canales, CSC and Roque-Borda, CA and Pavan, FR}, title = {Advancing Nanotechnology: Targeting Biofilm-Forming Bacteria with Antimicrobial Peptides.}, journal = {BME frontiers}, volume = {6}, number = {}, pages = {0104}, pmid = {40041091}, issn = {2765-8031}, abstract = {Nanotechnology offers innovative solutions for addressing the challenges posed by biofilm-forming bacteria, which are highly resistant to conventional antimicrobial therapies. This review explores the integration of pharmaceutical nanotechnology with antimicrobial peptides (AMPs) to enhance the treatment of biofilm-related infections. The use of various nanoparticle systems-including inorganic/metallic, polymeric, lipid-based, and dendrimer nanostructures-provides promising avenues for improving drug delivery, targeting, and biofilm disruption. These nanocarriers facilitate the penetration of biofilms, down-regulate biofilm-associated genes, such as ALS1, ALS3, EFG1, and HWP1, and inhibit bacterial defense mechanisms through membrane disruption, reactive oxygen species generation, and intracellular targeting. Furthermore, nanoparticle formulations such as NZ2114-NPs demonstrate enhanced efficacy by reducing biofilm bacterial counts by several orders of magnitude. This review highlights the potential of combining nanotechnology with AMPs to create novel, targeted therapeutic approaches for combatting biofilm-related infections and overcoming the limitations of traditional antimicrobial treatments.}, }
@article {pmid40040432, year = {2025}, author = {Mukherjee, S and Chakravarty, S and Haldar, J}, title = {Revitalizing Antibiotics with Macromolecular Engineering: Tackling Gram-Negative Superbugs and Mixed Species Bacterial Biofilm Infections In Vivo.}, journal = {Biomacromolecules}, volume = {}, number = {}, pages = {}, doi = {10.1021/acs.biomac.4c01520}, pmid = {40040432}, issn = {1526-4602}, abstract = {The escalating prevalence of multidrug-resistant Gram-negative pathogens, coupled with dwindling antibiotic development, has created a critical void in the clinical pipeline. This alarming issue is exacerbated by the formation of biofilms by these superbugs and their frequent coexistence in mixed-species biofilms, conferring extreme antibiotic tolerance. Herein, we present an amphiphilic cationic macromolecule, ACM-AHex, as an innovative antibiotic adjuvant to rejuvenate and repurpose resistant antibiotics, for instance, rifampicin, fusidic acid, erythromycin, and chloramphenicol. ACM-AHex mildly perturbs the bacterial membrane, enhancing antibiotic permeability, hampers efflux machinery, and produces reactive oxygen species, resulting in a remarkable 64-1024-fold potentiation in antibacterial activity. The macromolecule reduces bacterial virulence and macromolecule-drug cocktail significantly eradicate both mono- and multispecies bacterial biofilms, achieving >99.9% bacterial reduction in the murine biofilm infection model. Demonstrating potent biocompatibility across multiple administration routes, ACM-AHex offers a promising strategy to restore obsolete antibiotics and combat recalcitrant Gram-negative biofilm-associated infections, advocating for further clinical evaluation as a next-generation macromolecular antibiotic adjuvant.}, }
@article {pmid40038354, year = {2025}, author = {Ammar, HA and Samy, R and Reda, FM and Hassanein, WA}, title = {Essential oils and Lactobacillus metabolites as alternative antibiofilm agents against foodborne bacteria and molecular analysis of biofilm regulatory genes.}, journal = {Scientific reports}, volume = {15}, number = {1}, pages = {7576}, pmid = {40038354}, issn = {2045-2322}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Oils, Volatile/pharmacology ; *Anti-Bacterial Agents/pharmacology ; *Bacillus cereus/drug effects/genetics/physiology ; *Microbial Sensitivity Tests ; Food Microbiology ; Lactobacillus/drug effects/genetics/metabolism ; Gene Expression Regulation, Bacterial/drug effects ; Foodborne Diseases/prevention &amp; control/microbiology ; Genes, Regulator ; Lactobacillus pentosus/genetics/metabolism ; }, abstract = {The formation of biofilm by foodborne pathogens increases the risk of foodborne diseases, resulting in major health risks. Research on strategies for eliminating biofilm formation by foodborne pathogens is urgently needed. Therefore, the objective of this study was to construct a new technique for controlling foodborne bacteria and inhibiting the biosynthesis of biofilm via using natural products. The essential orange oil (EOO) and cell-free filtrate of Lactobacillus pentosus RS2 were used as antibacterial and antibiofilm agents against B. cereus RS1, the strongest biofilm-forming strain. The mixture of cell-free filtrate (CFF) and EOO (CFF/EOO) was the best antibiofilm agent under all tested conditions. The minimal inhibitory concentration (MIC) test revealed that 400 μl ml[-1] CFF and 16 μl ml[-1] EOO completely inhibited the growth of B. cereus. The treatment of three commercial surfaces with CFF/EOO resulted in a high reduction in biofilm synthesis, with adhesion percentages of 33.3, 36.3, and 40.8% on stainless steel, aluminum foil, and aluminum, respectively. The aluminum surface had the greatest adhesion with B. cereus RS1 among the three tested surfaces. These results were confirmed by expression analysis of three essential coding genes, sinR, calY, and spo0A, participating in biofilm formation in B. cereus. The biofilm-negative regulator gene sinR was overexpressed, whereas the biofilm-positive regulator genes calY and spo0A were down-expressed in B. cereus RS1 after treatment with antibiofilm agents, compared with those in the untreated sample. This study revealed that CFF/EOO was more effective at activating sinR (2.099 ± 0.167-fold increase) and suppressing calY and spo0A (0.314 ± 0.058 and0.238 ± 0.04-fold decrease, respectively) compared to control. This result confirmed the biochemical estimation of biofilm formation in B. cereus after treatment with all the experimental agents. The EOO and CFF of L. pentosus RS2 can be used as strong antibacterial and antibiofilm agents against foodborne bacteria. These products reduced the biofilm formation on trade surfaces affecting the expression of three essential biofilm regulatory genes. This study considered novel research concerning the potential antibiofilm activity of EOO combined with CFF of L. pentosus and the molecular analysis of genes regulating biofilm production under stress of CFF/EOO.}, }
@article {pmid40037188, year = {2025}, author = {Ding, Y and Wang, J and Chen, Y and Yang, Y and Liu, X}, title = {Natural transformation of antibiotic resistance genes and the enhanced adaptability in bacterial biofilm under antibiotic and heavy metal stresses.}, journal = {Journal of hazardous materials}, volume = {490}, number = {}, pages = {137740}, doi = {10.1016/j.jhazmat.2025.137740}, pmid = {40037188}, issn = {1873-3336}, abstract = {Bacterial biofilms are hotspots for the natural transformation of antibiotic resistance genes (ARGs). Antibiotics and heavy metals at the sub-minimal inhibitory concentrations (sub-MICs) are ubiquitous in water environments, but their impact on the ARG dissemination via natural transformation in biofilms and the biofilm development remains poorly understood. This study found that the individual stressors including tetracycline, sulfamethoxazole, and Zn at the sub-MIC levels, significantly enhanced ARG transformation. Notably, Zn exhibited the most obvious effect, increasing transformation frequencies by up to 4.62-fold in B. subtilis and 6.42-fold in A. baylyi biofilms. Their combined stressors increased the higher ARG transformation compared to the individual. These stressors significantly elevated ARG transformation by stimulating reactive oxygen species generation, increasing membrane permeability, and enhancing polysaccharide production. Meanwhile, the bacterial adaptability in biofilm to stressors was achieved via ARG transformation, and the biofilm growth was increased by 25.4 % in B. subtilis and 49.6 % in A. baylyi, respectively, compared to biofilms without natural transformation. Except for ARG uptake via transformation, the enhanced bacterial adaptability in biofilms to stressors can also be attributed to the expression of the plasmid-borne SOS response-related genes. These findings broaden the understanding of the influence of sub-MIC stressors in ARG dissemination in biofilm.}, }
@article {pmid40037051, year = {2025}, author = {Gemba, M and Rosiak, E and Kołożyn-Krajewska, D}, title = {Development of predictive models of biofilm formation by C. sakazakii, E. cloacae on surfaces used in the food industry and medicine.}, journal = {International journal of food microbiology}, volume = {434}, number = {}, pages = {111131}, doi = {10.1016/j.ijfoodmicro.2025.111131}, pmid = {40037051}, issn = {1879-3460}, abstract = {Cronobacter sakazakii and Enterobacter cloacae exhibit the ability to form biofilms, making them resistant to drying, antibiotics, and changes in pH. These biofilms can adhere to different surfaces, including tissues, catheters, enteral feeding tubes, and work surfaces, potentially leading to cross-infection risks in both the food and medical sectors. The objective of this study was to develop a predictive model of biofilm formation over time by C. sakazakii and E. cloacae on medical polyvinyl chloride (PVC) at 37 °C and stainless steel (SS), polypropylene (PP) surfaces at 4 °C and different microbial inoculum concentration. A staining method and spectrophotometric measurement were used to assess biofilm formation. SyStat Software Inc. for Windows Table curve 3D v.4.0.05 and non-linear functions were used to develop predictive models. Analysis of biofilm formation on SS and PP surfaces at 4 °C by all analyzed bacteria suggests that hygiene procedures in refrigeration equipment should be performed daily, the maximum safe storage time for bottled milk is 24 h. At 37 °C E. cloacae posed the highest risk of biofilm formation on the surface of PVC tubing at 6-36 h. The six best response surface models of biofilm formation were selected for presentation. The majority of these models demonstrated good accuracy, as evidenced low mean standard errors (MSE), high coefficient R[2] and Adjusted R(Aung and Chang, 2014[2)]. These models can be utilized to evaluate the microbiological risks in settings such as human milk banks, neonatal intensive care units and food industry plants.}, }
@article {pmid40035601, year = {2025}, author = {Jones, LM and Salta, M and Lund Skovhus, T and Thomas, K and Illson, T and Wharton, J and Webb, JS}, title = {Toward simulating offshore oilfield conditions: insights into microbiologically influenced corrosion from a dual anaerobic biofilm reactor.}, journal = {Applied and environmental microbiology}, volume = {}, number = {}, pages = {e0222124}, doi = {10.1128/aem.02221-24}, pmid = {40035601}, issn = {1098-5336}, abstract = {UNLABELLED: Oilfield systems are a multifaceted ecological niche, which consistently experiences microbiologically influenced corrosion. However, simulating the environmental conditions of an offshore system within the laboratory is notoriously difficult. A novel dual anaerobic biofilm reactor protocol allowed a complex mixed-species marine biofilm to be studied. Interestingly, electroactive corrosive bacteria and fermentative electroactive bacteria growth was supported within the biofilm microenvironment. Critically, the biotic condition exhibited pits with a greater average area, which is characteristic of microbiologically influenced corrosion. This research seeks to bridge the gap between experimental and real-world scenarios, ultimately enhancing the reliability of biofilm management strategies in the industry.<br><br>IMPORTANCE: It is becoming more widely understood that any investigation of microbiologically influenced corrosion requires a multidisciplinary focus on multiple lines of evidence. Although there are numerous standards available to guide specific types of testing, there are none that focus on integrating biofilm testing. By developing a novel dual anaerobic reactor model to study biofilms, insights into the different abiotic and biotic corrosion mechanisms under relevant environmental conditions can be gained. Using multiple lines of evidence to gain a holistic understanding, more sustainable prevention and mitigation strategies can be designed. To our knowledge, this is the first time all these metrics have been combined in one unified approach. The overall aim of this paper was to explore recent advances in biofilm testing and corrosion research and provide recommendations for future standards being drafted. However, it is important to note that this article itself is not intending to serve as a standard.}, }
@article {pmid40034339, year = {2025}, author = {Oukrich, S and Hong, J and Leon-Grooters, M and van Cappellen, WA and Slotman, JA and Koenderink, GH and van Wamel, WJB and de Maat, MPM and Kooiman, K and Lattwein, KR}, title = {Early fibrin biofilm development in cardiovascular infections.}, journal = {Biofilm}, volume = {9}, number = {}, pages = {100261}, pmid = {40034339}, issn = {2590-2075}, abstract = {The single most common microbe causing cardiovascular infections is Staphylococcus aureus (S. aureus). S. aureus produces coagulase that converts fibrinogen to fibrin, which is incorporated into biofilms. This process aids in adherence to intravascular structures, defense against the host immune system, and resistance to antimicrobial treatment. Despite its significance, fibrin formation in S. aureus biofilms remains poorly understood. Therefore, this study aimed to elucidate the early development of cardiovascular biofilms. Clinically isolated coagulase-positive S. aureus and coagulase-negative Staphylococcus lugdunensis (S. lugdunensis) from patients with cardiovascular infections, and a coagulase mutant S. aureus Δcoa, were grown in tryptic soy broth (TSB), Iscove's Modified Dulbecco's Medium (IMDM), and pooled human plasma, with or without porcine heart valves. Bacterial growth, metabolic activity, and bacterial fibrinogen utilization were measured over 24 h at 37 °C. Time-lapse confocal microscopy was used to visualize and track biofilm development. S. aureus exhibited more growth in TSB and human plasma than S. lugdunensis and S. aureus Δcoa, but showed similar growth in IMDM after 24 h. Peak metabolic activity for all isolates was highest in TSB and lowest in human plasma. The presence of porcine valves caused strain-dependent alterations in time to peak metabolic activity. Confocal imaging revealed fibrin-based biofilm development exclusively in the coagulase-producing S. aureus strains. Between 2 and 6 h of biofilm development, 74.9 % (p = 0.034) of the fibrinogen from the medium was converted to fibrin. Variations in fibrin network porosity and density were observed among different coagulase-producing S. aureus strains. Fibrin formation is mediated by S. aureus coagulase and first strands occurred within 3 h for clinical strains after exposure to human plasma. This study stresses the importance of experimental design given the bacterial changes due to different media and substrates and provides insights into the early pathogenesis of S. aureus cardiovascular biofilms.}, }
@article {pmid40033797, year = {2025}, author = {Nick, SE and Bryers, JD and Daggett, V}, title = {Layer-By-Layer Functionalized Gauze With Designed α-Sheet Peptides Inhibits E. coli and S. aureus Biofilm Formation.}, journal = {Journal of biomedical materials research. Part A}, volume = {113}, number = {3}, pages = {e37879}, doi = {10.1002/jbm.a.37879}, pmid = {40033797}, issn = {1552-4965}, support = {//US Army Medical Research Acquisition Activity (USAMRAA)/ ; //Department of Defense Office of the Congressionally Directed Medical Research Programs (CDMRP)/ ; W81XWH-19-0050//Peer Reviewed Medical Research Program (PRMRP)/ ; 6R01AI074661//National Institutes of Health/National Institute of Allergies and Infectious Diseases/ ; TL1 TR002318/TR/NCATS NIH HHS/United States ; //the NIH National Center for Advancing Translational Sciences/ ; //Clinical and Translational Science Awards Program (CTSA)/ ; NNCI-1542101//National Science Foundation/ ; NNCI-2025489//National Science Foundation/ ; }, mesh = {*Biofilms/drug effects ; *Staphylococcus aureus/drug effects ; *Escherichia coli/drug effects ; Humans ; *Bandages ; Peptides/pharmacology/chemistry ; Alginates/chemistry/pharmacology ; Anti-Bacterial Agents/pharmacology ; Chitosan/chemistry/pharmacology ; }, abstract = {Microbial biofilms on wounds lead to longer hospital stays, mechanical debridement, and higher mortality. Amyloid fibrils stabilize the bacterial biofilm's extracellular matrix (ECM) and represent a potential anti-biofilm target. As previously reported, de novo α-sheet peptides inhibit amyloid fibrillization and reduce biofilm formation in several bacterial species. Alginate (ALG) and chitosan (CH) are widely used in wound dressings due to their adhesive and antimicrobial activity. Here, we describe a layer-by-layer (LbL) functionalized gauze with alternating layers of ALG and CH loaded with α-sheet peptides for controlled release and biofilm inhibition at a wound site. Material analysis indicated successful LbL polyelectrolyte deposition and peptide incorporation. The LbL gauze facilitated controlled peptide release for 72 h with an initial burst delivery and demonstrated good biocompatibility with no toxicity towards human fibroblasts. The LbL gauze was assessed against Escherichia coli biofilms and reduced colony forming units (CFUs) of adherent bacteria by 81% and 96% as compared to the plain gauze for non-antibiotic and antibiotic (+gentamicin) conditions, respectively. A similar reduction in biofilm formation and increase in antibiotic susceptibility was observed for tests with Staphylococcus aureus and vancomycin. Thus, LbL gauze with incorporated α-sheet peptides demonstrated anti-biofilm properties for both gram-negative and gram-positive bacteria and presents an alternative wound dressing for the prevention of biofilm-associated infections.}, }
@article {pmid40033365, year = {2025}, author = {Stephen, AS and Chala, V and Nicolas, CS and Jasmin, P and Allaker, RP}, title = {Antimicrobial activity of ear cleanser products against biofilm and planktonic phases of Staphylococcus spp. and Pseudomonas spp. isolated from canine skin and ear infections.}, journal = {BMC veterinary research}, volume = {21}, number = {1}, pages = {137}, pmid = {40033365}, issn = {1746-6148}, mesh = {Animals ; *Biofilms/drug effects ; Dogs ; *Staphylococcus/drug effects ; *Dog Diseases/microbiology/drug therapy ; *Microbial Sensitivity Tests ; Pseudomonas aeruginosa/drug effects/physiology ; Anti-Bacterial Agents/pharmacology ; Pseudomonas Infections/veterinary/microbiology/drug therapy ; Pseudomonas/drug effects/isolation &amp; purification ; Otitis Externa/veterinary/microbiology ; }, abstract = {BACKGROUND: Staphylococcus spp., and Pseudomonas spp., including multidrug resistant staphylococci are frequent isolates from canine otitis externa and atopic dermatitis. The ability of these bacteria to form biofilms significantly contributes to the chronic nature of otitis. To manage microbial overgrowth, ear cleanser products are commonly used. It is important therefore, to measure their antibiofilm effects. In this study, six ear cleansers (Epiotic[Ⓡ] SIS, Epiotic[Ⓡ] Advanced, Cleanaural[Ⓡ], Otifree[Ⓡ], Peptivet[Ⓡ] and Sonotix[Ⓡ]) were evaluated against clinical isolates of Pseudomonas aeruginosa, methicillin resistant and sensitive Staphylococcus aureus and Staphylococcus pseudintermedius. Antibiofilm activity was measured using a colorimetric assay that detects viable cells through the reduction of thiazolyl blue tetrazolium bromide (MTT). Additionally, minimum inhibitory concentration (MIC) of Epiotic SIS and Epiotic Advanced were determined using a broth micro-dilution assay to assess their ability to inhibit bacteria in the planktonic state.<br><br>RESULTS: Epiotic (SIS and Advanced), Cleanaural and Peptivet showed high antibiofilm activity, with Otifree and Sonotix showing moderate to low antibiofilm activity. Notably, Otifree was significantly less effective at inhibiting methicillin-resistant S. aureus compared to methicillin-sensitive strains. P. aeruginosa biofilms were less effectively disrupted by some ear cleansers, and the MIC results indicated that less diluted solutions were required to inhibit this isolate compared to the staphylococcal species. Differences in the antibacterial effects between Epiotic SIS and Epiotic Advanced solutions could also be detected from the MIC assays suggesting differences in formulations can affect antimicrobial efficacy.<br><br>CONCLUSIONS: Commonly used canine ear cleanser products showed variable activity against multidrug resistant and sensitive Staphylococcus spp. and P. aeruginosa isolates in both biofilm and planktonic phases. The observed differences between bacterial strains and cleanser formulations highlight the importance of selecting appropriate products for targeted microbial control, which can lead to more effective management of chronic otitis externa and atopic dermatitis in dogs.}, }
@article {pmid40032222, year = {2025}, author = {Higgins, A and Wood, PJ and Mathers, KL}, title = {Microfibre ingestion by the Asian Clam (Corbicula fluminea) is dependent on fibre type and biofilm development.}, journal = {Environmental pollution (Barking, Essex : 1987)}, volume = {}, number = {}, pages = {125962}, doi = {10.1016/j.envpol.2025.125962}, pmid = {40032222}, issn = {1873-6424}, abstract = {Fibrous microplastics represent an anthropogenic pollutant affecting aquatic systems globally. However, fibres formed from natural materials (e.g., cotton or wool) have only recently been recognised as potentially posing similar ecological threats as their synthetic counterparts. In this study we employed a laboratory-based aquarium experiment to examine the ingestion of preselected anthropogenic (polyester - microplastic) and 'natural' (cotton) microfibres by the Asian Clam (Corbicula fluminea). We considered how the ingestion, retention, and rejection of preselected microfibres (specific, distinctive colours), differed associated with fibre type (cotton vs polyester), biofilm development (control - no biofilm / uncultured, 1-week culturing and 4-week culturing) and time (1-48 hours). We found that the ingestion of microfibres was complex, dependent on the interaction of culturing and fibre type. Greater retention of synthetic microfibres was recorded compared to 'natural' microfibres as the duration of culturing increased. We also observed that ingestion of microfibres was immediate but that microfibres were rejected and visually observed in pseudofaeces. Our results suggest that the time microfibres spend within the environment, allowing biofilm to develop on their surface, influences the ingestion of microfibres and we call for further studies to consider this in the future.}, }
@article {pmid40032003, year = {2025}, author = {Liao, C and Hu, J and Mao, F and Li, Q and Li, H and Yu, C and Jia, Y and Ding, K}, title = {Extracellular TatD from Listeria monocytogenes displays DNase activity and contributes to biofilm dispersion.}, journal = {Microbial pathogenesis}, volume = {}, number = {}, pages = {107445}, doi = {10.1016/j.micpath.2025.107445}, pmid = {40032003}, issn = {1096-1208}, abstract = {TatD is evolutionarily conserved in a variety of organisms and has been implicated in DNA repair, apoptosis, and the disruption of extracellular traps. The aim of our study was to investigate the effects of TatD on L. monocytogenes biofilms. In our previous study, the deletion of the TatD gene from L. monocytogenes (named LmTatD) increased biofilm formation. However, the underlying mechanism remains unclear. In this study, we present a detailed analysis of the structural characteristics of TatD. Bioinformatic analysis revealed that the amino acid residues DPGEGDQHEDP are fully conserved. LmTatD belongs to the Class II TatD family (TATDN3) and contains a signal peptide. Recombinant LmTatD exhibited DNase activity regardless of the DNA substrate. Mutagenesis experiments confirmed the importance of glutamic acid, histidine, and aspartic acid residues in enzymatic activity. Biofilm formation was evaluated via a crystal violet assay, confocal laser scanning microscopy, and scanning electron microscopy. rLmTatD impaired biofilm formation and reduced eDNA levels without disrupting the integrity of the bacteria within biofilms. Moreover, deficiency of LmTatD led to a significant decrease in the DNase activity of the extracellular proteins from L. monocytogenes, whereas there was an increase in biofilm formation and eDNA production during the dispersion stage. However, no significant change in the total number of biofilm or planktonic bacteria was observed at any of the time points. Additionally, the mRNA level of LmTatD in the biofilm formed by the wild-type strain at the dispersion stage was greater than that at the attachment and maturation stages. The number of planktonic bacteria for the wild-type strain at the dispersion stage was significantly greater than that for the ΔLmTatD mutant. Collectively, these data suggest that LmTatD exhibits extracellular DNase activity and regulates L. monocytogenes biofilm dispersion.}, }
@article {pmid40032001, year = {2025}, author = {Van Nederveen, V and Johnson, YS and Ortega, E and Soc, A and Smith, MA and Melton-Celsa, AR}, title = {Role of aggregative adherence fimbriae from enteroaggregative Escherichia coli isolates in biofilm and colonization.}, journal = {Microbial pathogenesis}, volume = {}, number = {}, pages = {107444}, doi = {10.1016/j.micpath.2025.107444}, pmid = {40032001}, issn = {1096-1208}, abstract = {Enteroaggregative Escherichia coli (EAEC) are a diverse group of bacteria that cause diarrhea worldwide. EAEC significantly affect travelers to endemic regions, including military personnel, and children in developing countries where EAEC infection is associated with childhood failure-to-thrive. EAEC creates thick biofilms on the intestinal mucosa, a process that is thought to contribute to the development of both diarrhea and childhood failure-to-thrive. Typical EAEC strains encode and produce just one aggregative adherence fimbriae (AAF) out of the five different AAF types. The AAF are required for aggregative adherence to epithelial cells in vitro, but the degree of importance of each of the AAF types in both biofilm formation and pathogenesis is unknown. In this study, we investigated the role of the fimbriae in EAEC biofilms by deleting the major fimbrial subunit gene for the AAF from each of the five AAF categories and observing the impact on biofilm staining from recent EAEC clinical isolates. We found that biofilm was significantly reduced in all strains when the AAF gene was deleted, and that the defect could be overcome by complementation. In this work we also describe a modified murine EAEC model appropriate for colonization studies. In an antibiotic-treated mouse colonization model, some AAF mutant strains were attenuated for colonization, including AAF/II, AAF/IV, and AAF/V isolates. We did not observe complementation of the attenuated colonization phenotype in the mouse model. However, since we found a colonization defect for several EAEC mutant strains of different AAF types, a link between the fimbriae and colonization in the mice is supported. Taken together, our results show that the AAF are required for biofilm formation, and that some AAF contribute to colonization in a mouse model.}, }
@article {pmid40031973, year = {2025}, author = {Xie, M and Yang, M and Li, X and DU, Y}, title = {[Low-intensity pulsed ultrasound combined with nystatin treatment synergistically inhibits vaginal Candida albicans biofilm infection in rabbits].}, journal = {Nan fang yi ke da xue xue bao = Journal of Southern Medical University}, volume = {45}, number = {2}, pages = {296-303}, doi = {10.12122/j.issn.1673-4254.2025.02.10}, pmid = {40031973}, issn = {1673-4254}, mesh = {Animals ; Female ; Rabbits ; *Biofilms/drug effects ; *Nystatin/pharmacology ; *Candida albicans/drug effects ; *Antifungal Agents/pharmacology ; *Ultrasonic Waves ; *Microbial Sensitivity Tests ; Vagina/microbiology ; Reactive Oxygen Species/metabolism ; Candidiasis, Vulvovaginal/therapy/microbiology ; }, abstract = {OBJECTIVES: To explore the efficacy of low-intensity pulsed ultrasound (LIPUS) combined with nystatin for treatment of vaginal Candida albicans biofilm infection.<br><br>METHODS: In vitro cultured Candida albicans biofilm were treated with LIPUS, nystatin, or both, and the minimum inhibitory concentration (MIC) of nystatin was determined. Crystal violet staining, confocal laser microscopy (CLSM) and scanning electron microscopy were used to quantify the biofilm and observe the activity and morphological changes of the biofilms; DCFH-DA was used to detect the changes in reactive oxygen species (ROS). Twenty female New Zealand White rabbits with vaginal inoculation of Candida albicans biofilm were randomized into 4 groups for treatment with normal saline, LIPUS, nystatin, or both LIPUS and nystatin. The changes in vulvar symptoms of the rabbits were observed, and the histopathological and ultrastructural changes of the vagina before and after treatment were observed using HE staining and transmission electron microscopy.<br><br>RESULTS: In the combined treatment group, the MIC50 and MIC80 of nystatin in Candida albicans biofilms were both reduced by 50% compared with those in nystatin group, and the biofilm clearance rate increased by 26% and 68% compared with nystatin and LIPUS groups, respectively. Compared with nystatin and LIPUS treatment alone, the combined treatment produced stronger effects for inhibiting biofilm activity, causing structural disruption and promoting ROS production. In the rabbit models, the combined treatment more effectively improved vulvar symptoms and inflammatory infiltration, reduced residual vaginal hyphae/strains, and improved ultrastructure of the vaginal epithelium than LIPUS and nystatin treatment alone.<br><br>CONCLUSIONS: LIPUS combined with nystatin produces a significant synergistic antifungal effect against Candida albicans biofilm both in vitro and in vivo.}, }
@article {pmid40030140, year = {2025}, author = {Wang, Z and Yan, Q and Song, M and Aimaier, X and Liu, X and Zhang, B and Han, Z and Liu, Y and Dan, Y and Huang, J and Hu, X and Wen, J and Li, H}, title = {Bacillus licheniformis Extracellular Polymeric Substances Conditioning Layer Mediates the Bacterial Adhesion Behaviors toward Controlled Biofilm Formation.}, journal = {Langmuir : the ACS journal of surfaces and colloids}, volume = {}, number = {}, pages = {}, doi = {10.1021/acs.langmuir.4c04292}, pmid = {40030140}, issn = {1520-5827}, abstract = {In aquatic environments, conditioning layers play a crucial role in modulating the adhesion and aggregation of planktonic bacteria, ultimately facilitating biofilm formation and the irreversible onset of biofouling. This study reports the construction of a simplified conditioning layer using extracellular polymeric substances (EPS) secreted by Bacillus licheniformis and its influence on the adherence behaviors of bacteria. The results reveal that the EPS conditioning layer remarkably inhibits the Staphylococcus aureus adherence yet promotes the aggregation of Escherichia coli. The surface of the EPS conditioning layer shows a flat morphology with the highest height of approximately 12.9 nm. The conditioning layer alters the physicochemical properties of the substrate materials on their surfaces, with water contact angles changing from 61.23° to 8.76° and the zeta potential changing from -1.0 to -25.0 mV. Despite these changes, the overall effect of the EPS conditioning layer on bacterial adhesion was found to be minimal. Further investigation on the bacterial adhesion and aggregation behaviors shows that two main components of EPS, namely, polysaccharides and bacitracin, affect the bacterial adhesion and aggregation behaviors. Bacitracin plays a predominant role in inhibiting the Staphylococcus aureus attachment, and the polysaccharides promote Escherichia coli aggregation. These findings would give inspiring insight into developing environmentally friendly efficient biological measures for combating the worldwide persisting biofouling.}, }
@article {pmid40029802, year = {2025}, author = {Zhou, Y and Zhou, X and Zhang, J and Zhao, Y and Ye, Z and Xu, F and Li, F}, title = {Confined Mechanical Microenvironment Regulated Antibiotic Resistance in 3D Biofilm Aggregates Probed by Scanning Electrochemical Microscopy.}, journal = {Analytical chemistry}, volume = {}, number = {}, pages = {}, doi = {10.1021/acs.analchem.4c05503}, pmid = {40029802}, issn = {1520-6882}, abstract = {Antibiotic resistance is a significant global concern. Clinical trials have highlighted discrepancies in antibiotic doses between in vivo three-dimensional (3D) biofilms and in vitro two-dimensional biofilm models. A critical factor often overlooked is the confined mechanical microenvironment (e.g., host extracellular matrix (ECM) stiffness) surrounding the in vivo biofilms, leading to inaccurate diagnosis and increased antibiotic resistance. Herein, we designed a 3D agarose-gel-based in vitro biofilm model and applied scanning electrochemical microscopy (SECM) to monitor the metabolic dynamics in situ, including cellular respiration and reactive oxygen species of an embedded single biofilm aggregate. We discovered distinct respiration patterns for biofilm aggregates embedded in stiff and soft gels at the single aggregate level, which was corroborated by transcriptional analysis. Our findings indicate that mechanical cues mediate antibiotic tolerance by reducing metabolic activity and increasing the production of extracellular polymeric substances (EPS). Additionally, we identified that metabolite glycine enhances the tricarboxylic acid cycle, suggesting its potential as an adjuvant to improve antibiotic efficacy. Knocking out the upregulated EPS-related gene (ΔyjbE) results in significantly reduced survival rates of ΔyjbE mutants in stiff agarose gels compared to the wild type, thereby enhancing antibiotic efficacy. Overall, our study demonstrates the versatility of the SECM-based strategy for investigating both metabolic dynamics and antibiotic resistance in biofilms and uncovers the role of ECM stiffness in mediating antibiotic resistance in 3D biofilms, paving the way for improved clinical strategies in antibiotic treatment.}, }
@article {pmid40029176, year = {2025}, author = {Xiong, K and Long, L and Xing, J and Luo, L and Zhou, C and Wang, X and Shao, S}, title = {Biofilm-Induced Critical Flux in Dead-End Ultrafiltration Processes: Phenomenon, Mechanism, and Economic and Environmental Benefits.}, journal = {Environmental science &amp; technology}, volume = {}, number = {}, pages = {}, doi = {10.1021/acs.est.4c11760}, pmid = {40029176}, issn = {1520-5851}, abstract = {The concept of critical flux, introduced by R.W. Field, defines the flux below which the filtration resistance remains constant over time. Notably, this concept, originally for cross-flow filtration, faces challenges in dead-end filtration (the dominant mode used in drinking water ultrafiltration (UF)). Herein, leveraged by regulated membrane biofilms, we proposed a novel biofilm-induced critical flux specific to dead-end filtration. Below this critical flux, the membrane biofilm could act like a cross-flow to maintain mass balances by the biodegradation of foulants, thereby preventing a continuous increase in filtration resistance. Additionally, we demonstrated an optimized strategy to improve the critical flux─backwashing without air scouring, which doubled the critical flux from 6 to 12 L·m[-2]·h[-1]. A life cycle analysis revealed that operating at the biofilm-induced critical flux can reduce energy consumption and minimize membrane cleaning, thereby effectively lowering the overall operating costs (52%) and carbon emissions (61%) compared to conventional UF. Sensitivity analysis also indicated that extending membrane life and reducing membrane costs were crucial for lowering overall operating costs, while minimizing fossil energy usage was decisive for reducing carbon emissions. Overall, our study demonstrates that operating at a biofilm-induced critical flux offers a low-maintenance, cost-effective, and environmentally sustainable strategy for drinking water UF.}, }
@article {pmid40029048, year = {2025}, author = {Sales, LS and Silvestre, ALP and Chorilli, M and Meneguin, AB and Barud, HDS and Brighenti, FL}, title = {Evaluation of morin and carvacrol loaded-nanoparticles on oral polymicrobial biofilm control.}, journal = {Biofouling}, volume = {}, number = {}, pages = {1-17}, doi = {10.1080/08927014.2025.2471975}, pmid = {40029048}, issn = {1029-2454}, abstract = {This study aimed to develop and characterize sodium alginate (SA)/chitosan (CS) based nanoparticles (NPs), with or without morin or carvacrol, and to evaluate the antimicrobial and antibiofilm activity against polymicrobial oral biofilms. Three different NPs (0.15:1; 0.3:1; 0.5:1 CS:SA) whether or not containing morin or carvacrol were developed and characterized by particle size, zeta potential, scanning electron microscope (SEM), encapsulation efficiency, and in vitro drug release. NPs antibiofilm and antimicrobial activity were evaluated using polymicrobial oral biofilms by means of quantifying the biomass, assessment of viable microorganisms (CFU/mL), and acidogenicity of the biofilm by pH readings. The NPs presented nanometric size (<500 nm), with spherical shape and smooth surface. Encapsulation efficiency of the samples containing morin ranged from 46.17 to 55.15% and for carvacrol from 55.30 to 90.15%. Total release of carvacrol and morin occurred within 15 min. The NPs significantly reduced biofilm biomass and microbial viability compared to the control. However, did not significantly increase the biofilm pH. The NPs were effectively synthesized and showed antimicrobial and antibiofilm effect against oral biofilm and the addition of natural substances morin or carvacrol increased this effect. Combination of chitosan and sodium alginate and addition of morin or carvacrol in NPs can be a promising strategy for oral use, fighting biofilm and consequently biofilm dependent diseases.}, }
@article {pmid40028113, year = {2025}, author = {Marcolino, MC and Guimarães, ML and Fontes, ML and Resende, FA and Barud, HDS and Azevedo, AS and Azevedo, NF and de Oliveira, HP}, title = {Investigating Polypyrrole/Silver-Based Composite for Biofilm Prevention on Silicone Surfaces for Urinary Catheter Applications.}, journal = {ACS omega}, volume = {10}, number = {7}, pages = {7058-7068}, pmid = {40028113}, issn = {2470-1343}, abstract = {Catheter-associated urinary tract infections (CAUTIs) are among the most common healthcare-related infections caused by biofilm formation. This research investigated the efficacy of polypyrrole (PPy), silver nanoparticles (AgNPs), and their combination (PPy/AgNPs) as water-soluble additives applied in cleaning procedures for preventing the formation of Escherichia coli and Staphylococcus aureus (single and dual-species biofilms) on silicone. Ultraviolet-visible absorption assays, scanning electron microscopy (SEM) images, FTIR analysis, and dynamic light scattering experiments were conducted to evaluate the structure and physicochemical response of the antibiofilm compounds, with the biofilm prevention concentrations assessed by plate counting, flow cytometry, and SEM images. The composites proved to be dose-dependent agents preventing single- and dual-species biofilms from forming under simulated CAUTI conditions. Furthermore, cytotoxicity assays indicated that the materials are non-cytotoxic, supporting their suitability for biomedical applications. These findings pave the way for developing more effective, biocompatible catheter cleaning procedures, ultimately improving patient outcomes and addressing biofilms-related infections in clinical settings.}, }
@article {pmid40028012, year = {2025}, author = {Čukajne, T and Štravs, P and Sahin, O and Zhang, Q and Berlec, A and Klančnik, A}, title = {Campylobacter jejuni Biofilm Assessment by NanoLuc Luciferase Assay.}, journal = {Bio-protocol}, volume = {15}, number = {4}, pages = {e5192}, pmid = {40028012}, issn = {2331-8325}, abstract = {Campylobacter jejuni, a widespread pathogen found in birds and mammals, poses a significant risk for zoonosis worldwide despite its susceptibility to environmental and food-processing stressors. One of its main survival mechanisms is the formation of biofilms that can withstand various food-processing stressors, which is why efficient methods for assessing biofilms are crucial. Existing methods, including the classical culture-based plate counting method, biomass-staining methods (e.g., crystal violet and safranin), DNA-staining methods, those that use metabolic substrates to detect live bacteria (e.g., tetrazolium salts and resazurin), immunofluorescence with flow cytometry or fluorescence microscopy, and PCR-based methods for quantification of bacterial DNA, are diverse but often lack specificity, sensitivity, and suitability. In response to these limitations, we propose an innovative approach using NanoLuc as a reporter protein. The established protocol involves growing biofilms in microtiter plates, washing unattached cells, adding Nano-Glo luciferase substrate, and measuring bioluminescence. The bacterial concentrations in the biofilms are calculated by linear regression based on the calibration curve generated with known cell concentrations. The NanoLuc protein offers a number of advantages, such as its small size, temperature stability, and highly efficient bioluminescence, enabling rapid, non-invasive, and comprehensive assessment of biofilms together with quantification of a wide range of cell states. Although this method is limited to laboratory use due to the involvement of genetically modified organisms, it provides valuable insights into C. jejuni biofilm dynamics that could indirectly help in the development of improved food safety measures. Key features • Quantification of C. jejuni using NanoLuc luciferase. • The assay is linear in the range of 1.9 × 10[7] to 1.5 × 10[8] CFU/mL. • Following biofilm growth, less than 1 h is required for detection. • The assay requires genetically modified bacterial strains.}, }
@article {pmid40026327, year = {2024}, author = {Visvalingam, J and Zhang, P and Yang, X}, title = {Inter- and intra-species interactions between meat plant environmental bacteria and a non-biofilm-forming Escherichia coli O157:H7 strain in co-culture biofilms.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1517732}, pmid = {40026327}, issn = {1664-302X}, abstract = {This study evaluated the impact of meat-processing environmental bacteria (MPB) on biofilm formation by Escherichia coli O157:H7 in dual-species cultures. Biofilm development by 50 MPB and E. coli O157:H7 was assessed using crystal violet staining. Four MPB and E. coli O157:H7 combinations were evaluated further for viable cell numbers. A chlorinated alkaline agent and a quaternary ammonium-based agent were evaluated for their ability to remove biofilms. The E. coli O157:H7 strain was a non-biofilm former. In dual-species biofilms, if the companion MPB did not produce detectable biofilm, then the pairing did not produce measurable biofilms either. The interaction effect between MPB and E. coli O157:H7 was predominantly no-effect (neutral). Among the four MPB isolates tested by viable cell enumeration method, only generic E. coli genotype 136 reduced viable numbers of E. coli O157:H7 in dual-strain biofilm. Sequential treatment with cleaning and sanitizing treatment provided a better removal of biofilm than a single-agent treatment.}, }
@article {pmid40025994, year = {2025}, author = {Li, S and Ji, Y and Xue, X and Yang, Y and Huang, Y and Yang, S and Chen, X}, title = {Hierarchical biofilm models using sodium alginate beads containing bacteria embedded in a cellulose-chitosan hydrogel matrix.}, journal = {Journal of materials chemistry. B}, volume = {}, number = {}, pages = {}, doi = {10.1039/d4tb02015d}, pmid = {40025994}, issn = {2050-7518}, abstract = {In biofilm studies, a stable model is crucial for exploring infection mechanisms, antibiotic resistance, and evaluating materials' antibiofilm performance. Cultured biofilms often face challenges, such as slow maturation or rapid bacteria dispersion. Therefore, developing a stable, mature-stage biofilm model is critical for effective biofilm research. In this study, we report a beads-in-hydrogel biofilm model, in which sodium alginate (SA) hydrogel beads that contain bacteria are embedded within a chitosan-cellulose hydrogel film to simulate natural bacterial biofilms. This model can retain bacteria for a relatively long period of time, preventing their dispersion to the surrounding areas while keeping them viable. The reliability of the model was validated by measuring functional molecules, including extracellular DNA and biofilm-forming related proteins. Overall, this study presents a stable 3D beads-in-hydrogel biofilm model that effectively replicates natural biofilms, providing a reliable platform for exploring infection mechanisms, antibiotic resistance, and evaluating antibiofilm strategies.}, }
@article {pmid40023759, year = {2025}, author = {Kader, CB and de Smidt, O and Oosthuysen, J}, title = {Water Quality and Biofilm Formation in Dental Unit Waterline Systems in Mangaung, South Africa.}, journal = {International dental journal}, volume = {}, number = {}, pages = {}, doi = {10.1016/j.identj.2024.12.025}, pmid = {40023759}, issn = {1875-595X}, abstract = {BACKGROUND: Biofilm formation in dental unit waterlines (DUWLs) and the consequent microbial contamination of dental chair unit (DCU) water is a significant challenge. The South African government has no explicit requirements for water quality supplied to DCUs or for disinfection protocols for DUWLs.<br><br>AIM: To assess bacterial water quality and presence of biofilm-associated organisms in DUWLs of open and closed system DCUs.<br><br>METHODS: Standard water sampling was followed in accordance with the South African National Standard for drinking water (SANS 241:1) and used as reference for microbial water quality to measure heterotrophic plate counts (HPC) and total coliforms for possible water contamination. Pseudomonas aeruginosa and Legionella spp. are common opportunistic pathogens found in DUWL and were also assessed using selective media.<br><br>RESULTS: HPC exceeded the national standard of <10 &#xd7; 10[3] CFU mL[-1] in water from both open and closed systems (1.48-6.94 &#xd7; 10[4] CFU mL[-1] and 1.71 &#xd7; 10[4] CFU mL[-1]). P. aeruginosa was detected in fast handpieces, reservoir bottles, and distiller bottles of closed system DCUs. Legionella spp. (22 CFU mL[-1]) were present in the output water from one fast handpiece of an open system DCU. Internal surfaces of taps, fast handpieces, distiller bottles and reservoir bottles also exhibited mean HPC counts which exceeded the national standard. Total coliforms were identified in the fast handpieces of open system DCUs (5.09 &#xd7; 10[3] CFU 100 mL[-1]) and distiller bottles (6.23 &#xd7; 10[3] CFU 100 mL[-1]) of closed systems. P. aeruginosa (3.64 &#xd7; 10[4] CFU mL[-1]), was detected on the internal surfaces of the municipal tap supplying water to open system DCUs as well as, internal surfaces of reservoir bottles (5.9 &#xd7; 10[1] CFU 100 mL[-1]) and fast handpieces (1.5&#xd7;10[1] CFU 100 mL[-1]) of closed system DCUs.<br><br>CONCLUSION: Contamination levels of DUWL water and surfaces of open and closed system DCUs were high, highlighting the need for national regulations of DUWL quality and decontamination protocols in South Africa.}, }
@article {pmid40022849, year = {2025}, author = {Zhang, MY and Li, S and Han, YL and Shi, YF and Wu, YY and Cheng, J and Wang, CY and Zhou, XY and Zhang, YX}, title = {De novo-designed amphiphilic α-helical peptide Z2 exhibits broad-spectrum antimicrobial, anti-biofilm, and anti-inflammatory efficacy in acute Pseudomonas aeruginosa pneumonia.}, journal = {Bioorganic chemistry}, volume = {157}, number = {}, pages = {108309}, doi = {10.1016/j.bioorg.2025.108309}, pmid = {40022849}, issn = {1090-2120}, abstract = {Antimicrobial peptides (AMPs) show considerable promise in combating bacterial infections due to their broad-spectrum efficacy, unique mechanisms of action, and resistance capabilities. In this study, we de novo designed a series of α-helical AMPs (Z1-Z6) with enhanced antimicrobial activity, anti-biofilm, and anti-inflammatory effects. The design incorporated isoleucine with long alkyl side chains and carefully balanced the positive charge and hydrophobicity. Among the designed peptides, Z2 demonstrated remarkable properties. In vitro assays revealed a high therapeutic index, with effective inhibition of 10 pathogenic and drug-resistant bacterial strains by disrupting cell membranes and interacting with bacterial genomes. Z2 also significantly suppressed biofilm formation and reduced reactive oxygen species production in RAW264.7 cells, leading to a decrease in inflammatory cytokine expression, thus showing anti-inflammatory activity. In a mouse model of acute Pseudomonas aeruginosa pneumonia, Z2 significantly improved survival rates, efficiently cleared bacteria from the lungs, and alleviated lung damage. Overall, Z2's unique design endows it with excellent antimicrobial, anti-biofilm, and anti-inflammatory activities, suggesting its great potential as a novel antimicrobial agent for further development. Future research will focus on the studying the drug formulations, elucidating the mechanisms underlying Z2's anti-inflammatory effects and exploring its therapeutic potential in other infection models.}, }
@article {pmid40025436, year = {2025}, author = {Celebi, O and Baser, S and Guler, MC and Taghizadehghalehjoughi, A and Rakici, E and Aydin, E and Celebi, D}, title = {Molecular characterization of resistance and biofilm genes of ESKAPE pathogens isolated from clinical samples: examination of the effect of boric acid on biofilm ability by cell culture method.}, journal = {BMC microbiology}, volume = {25}, number = {1}, pages = {106}, pmid = {40025436}, issn = {1471-2180}, support = {Project No. TKP-2022-10754//Ataturk University Scientific Research Coordination Office/ ; Project No. TKP-2022-10754//Ataturk University Scientific Research Coordination Office/ ; Project No. TKP-2022-10754//Ataturk University Scientific Research Coordination Office/ ; Project No. TKP-2022-10754//Ataturk University Scientific Research Coordination Office/ ; Project No. TKP-2022-10754//Ataturk University Scientific Research Coordination Office/ ; Project No. TKP-2022-10754//Ataturk University Scientific Research Coordination Office/ ; Project No. TKP-2022-10754//Ataturk University Scientific Research Coordination Office/ ; }, abstract = {Biofilm formation ranks first among the resistance and virulence factors crucial in forming ESKAPE pathogens. Once biofilm is formed, treating the infection with existing drugs is often futile. Therefore, in this study, resistant ESKAPE pathogens were isolated from intensive care units and sent to Atatürk University Yakutiye Research Hospital Microbiology Laboratory. This study investigated the biofilm formation and molecular characterization of resistant ESKAPE pathogens isolated from intensive care units. The bacteria's biofilm formation abilities, genes responsible for biofilm formation, and resistance characteristics were identified. The effect of boric acid (BA) on resistance and bacterial genes was evaluated by a bacterial infection cell culture model. The highest biofilm formation was observed in Escherichia coli, Enterococcus spp., and Pseudomonas aeruginosa Enterococcus spp. isolates showed the vanA gene in 14.6% and the vanC gene in 61% of the samples. Among Staphylococcus spp. isolates, 48.3% were MSSA, 34.5% were MRCNS, and 17.2% were MRSA. The KPC gene was detected in 50%, the OXA-48 gene in 40%, and the NDM gene in 15% of the isolates. In P. aeruginosa, the LasI and LasR quorum sensing system genes were found in 38.5% and 30.8% of the isolates, respectively. In E. coli isolates, OXA-48 was present in 35%, KPC in 31.7%, and TEM in 12.5%. BA demonstrated significant activity against ESKAPE pathogens. The combined antimicrobial activity of boron compounds showed a decrease in the expression level of the resistance gene. It will be promising for preventing hospital-associated infections.}, }
@article {pmid40025431, year = {2025}, author = {Kakavan, M and Gholami, M and Ahanjan, M and Ebrahimzadeh, MA and Salehian, M and Roozbahani, F and Goli, HR}, title = {Expression of bap gene in multidrug-resistant and biofilm-producing Acinetobacter baumannii clinical isolates.}, journal = {BMC microbiology}, volume = {25}, number = {1}, pages = {108}, pmid = {40025431}, issn = {1471-2180}, support = {1431//Mazandaran University of Medical Sciences/ ; }, abstract = {INTRODUCTION: Acinetobacter baumannii is a significant biofilm-producer and antibiotic-resistant pathogen associated with various infections caused in humans. This study aimed to investigate the expression level of the bap gene in multidrug-resistant and biofilm-producer clinical isolates of A. baumannii.<br><br>MATERIALS AND METHODS: One Hundred A. baumannii clinical isolates were collected from hospitalized patients and identified by phenotypic and genotypic tests. The antibiotic resistance pattern of the isolates was determined by the disk agar diffusion method. The ability of biofilm production was investigated using the microtiter plate test. This study employed the Real-time PCR method to evaluate the expression level of the bap gene.<br><br>RESULTS: Ninety nine percent A. baumannii isolates were MDR. However, the highest resistance rate was observed against ciprofloxacin (100%), while ceftazidime was the most effective drug. Also, 49%, 49%, and 2% of the isolates were strong, moderate, and weak biofilm-producing, respectively. However, we detected no strain without the ability to produce biofilm. Most strong and moderate biofilm-former isolates were non-susceptible to all tested antibiotics. An increased expression level of the bap gene was detected in 99% of the isolates. The results of the present study suggest a correlation between the bap gene expression level and the development of multidrug resistance and biofilm formation in A. baumannii isolates.<br><br>CONCLUSION: This research emphasizes the importance of biofilm formation in the emergence of multidrug-resistant A. baumannii strains in healthcare settings, making them progressively difficult to control. The bap gene may be a considerable target for the development of novel anti-A. baumannii treatment option and eradication of the biofilm formation by this organism.}, }
@article {pmid40025202, year = {2025}, author = {Suchithra, KV and Hameed, A and Rekha, PD and Stothard, P and Arun, AB}, title = {A novel Kayvirus species phage RuSa1 removes biofilm and lyses multiple clinical strains of methicillin resistant Staphylococcus aureus.}, journal = {Scientific reports}, volume = {15}, number = {1}, pages = {7358}, pmid = {40025202}, issn = {2045-2322}, support = {YU/seed grant/127-2022//Yenepoya University/ ; }, mesh = {*Methicillin-Resistant Staphylococcus aureus/virology/genetics/physiology ; *Biofilms/growth &amp; development ; *Staphylococcus Phages/genetics/isolation &amp; purification/physiology ; *Phylogeny ; Genome, Viral ; Animals ; Staphylococcal Infections/microbiology/veterinary ; Deer/virology/microbiology ; India ; Humans ; }, abstract = {The emergence of methicillin-resistant Staphylococcus aureus (MRSA) infection is one of the global healthcare concerns. Here, we report the phenotypic and genotypic characterization of a novel multi-host Staphylococcus phage RuSa1, isolated from wastewater samples derived from a spotted sambar deer (Rusa unicolor) enclosure located at Mangalore, India. Clinical MRSA strains (n = 18) susceptible to RuSa1 were genetically and phenotypically diverse as determined by DNA fingerprinting and in vitro culture assays. RuSa1 displayed a latent period and burst size of 10 min and 50 PFU, respectively, and exhibited efficient biofilm removal activities against S. aureus ATCC BAA-44. The phage exhibited moderate UV stability (3 min) and high titre at 4-37 °C and pH 5‒9. RuSa1 possessed a linear double-stranded genomic DNA with a length of 140 kb. The genome contained 30.18% GC composition and shared 82.0‒94.9% sequence similarity with eleven authentic species of Kayvirus recognized by the International Committee on Taxonomy of Viruses based on VIRIDIC analysis. RuSa1 established distinct phyletic lineage in the maximum likelihood phylogenetic analysis of DNA encoding structural proteins and lacked genes that confer lysogeny. Based on the genotypic, phylogenetic and phenotypic data, RuSa1 is proposed to be a lytic phage and a new species of Kayvirus with a potential therapeutic ability against staphylococcal infections.}, }
@article {pmid40024356, year = {2025}, author = {Zhang, H and Zhang, Q and Zuo, T and Wang, Z and Liao, J and Lu, Y}, title = {2-Chloromethyl Anthraquinone Inhibits Candida Albicans Biofilm Formation by Inhibiting the Ras1-cAMP-Efg1 Pathway.}, journal = {Research in microbiology}, volume = {}, number = {}, pages = {104280}, doi = {10.1016/j.resmic.2025.104280}, pmid = {40024356}, issn = {1769-7123}, abstract = {Candida albicans is an opportunistic pathogen, and the formation of its biofilm makes it resistant to traditional antifungal therapy. Anthraquinones have universal antibacterial activity. We evaluated the inhibitory effects of 2-chloromethyl anthraquinone on C. albicans adhesion, mycelial morphology transformation, and biofilm formation. The results showed that 2-chloromethyl anthraquinone could inhibit C. albicans adhesion, mycelium formation, and biofilm formation in a dose-dependent manner at 2 μg/mL. In addition, 2-chloromethyl anthraquinone significantly inhibited the expression of biofilm formation-related genes in C. albicans, including ALS1, CPH1, ECE1, HWP1, TEC1, BCR1, and UME6. In addition, Ras1-cAMP-Efg1 pathway-related genes (RAC1, CYR1, and TPK2) were also significantly down-regulated, indicating that the inhibitory effect of 2-chloromethyl anthraquinone on C. albicans biofilms may be related to the Ras1-cAMP-Efg1 signaling pathway. In summary, the results of this study confirmed the inhibitory mechanism of 2-chloromethyl anthraquinone on the virulence factors of C. albicans, which laid a theoretical foundation for its use as an anti-biofilm agent against C. albicans.}, }
@article {pmid40023989, year = {2025}, author = {Wong, BC and Ling, FY and Ayub, Q and Tan, HS}, title = {Transposon mutagenesis identifies acid resistance and biofilm genes as Shigella sonnei virulence factors in Caenorhabditis elegans infection.}, journal = {Biochemical and biophysical research communications}, volume = {754}, number = {}, pages = {151546}, doi = {10.1016/j.bbrc.2025.151546}, pmid = {40023989}, issn = {1090-2104}, abstract = {Identifying essential genes in bacterial pathogens during infection can enhance knowledge and provide novel targets for antimicrobial agents' development. Currently, only Shigella flexneri essential genes during in vitro growth have been experimentally identified. This study used transposon insertion sequencing (TIS) to identify Shigella sonnei essential genes during Caenorhabditis elegans infection. 498 genes were predicted to be essential in S. sonnei during growth on nutrient-rich media. Some genes previously predicted to be essential in Shigella were found non-essential in S. sonnei, such as acetyl metabolism genes (aceEF, lpdA) and sulphate transport genes (cysA, cyst, cysW). Finally, 217 genes were predicted as S. sonnei virulence genes during infection, including acid resistance and biofilm formation genes which was not linked to S. sonnei virulence previously.}, }
@article {pmid40022417, year = {2025}, author = {Yuan, L and Liu, Y and Mi, Z and Xiong, D and Zhou, W and Xu, Z and Yang, Z and Jiao, XA}, title = {Dual-species biofilm and other profiles altered by interactions between Salmonella Typhimurium and Pseudomonas fluorescens isolated from meat.}, journal = {Food research international (Ottawa, Ont.)}, volume = {203}, number = {}, pages = {115914}, doi = {10.1016/j.foodres.2025.115914}, pmid = {40022417}, issn = {1873-7145}, mesh = {*Biofilms/growth &amp; development ; *Pseudomonas fluorescens/physiology/genetics/metabolism ; *Salmonella typhimurium/growth &amp; development/genetics/physiology ; *Meat/microbiology ; *Food Microbiology ; Animals ; }, abstract = {Salmonella Typhimurium is a significant foodborne pathogen that poses substantial health risks to humans. Pseudomonas fluorescens is a key bacterium responsible for meat deterioration through the production of spoilage-associated enzymes. Both species are widely presented in meat, and can form dense biofilms on slaughterhouse equipment surfaces, acting as persistent sources of bacterial contamination that compromise both safety and quality issues in the meat industry. However, how ecological interactions between S. Typhimurium and P. fluorescens affect the function and stability of mixed-species biofilms remain largely unexplored. The purpose of this work is to investigate the altered profiles of a mixed-species biofilm by meat-derived S. Typhimurium N25 and P. fluorescens PF2 through RNA-sequencing analysis in combined with phenotype validation, including the bacterial growth and antibiotic resistance of planktonic cells, biofilm-forming capacity, biofilm structures, and biofilm EPS production. The results demonstrated that the presence of S. Typhimurium inhibited the growth of P. fluorescens PF2 in its planktonic state, and reduced the biofilm cell count of P. fluorescens PF2 in mixed-species biofilm when compared to that in mono-species biofilm. Furthermore, the bacterial interaction led to decreased protein and carbohydrate contents in the biofilm matrix, and reductions in biofilm coverage, average thickness, and total biomass. RNA-sequencing analysis revealed that 580 differentially expressed genes (DEGs) were mainly involved in eight downregulated pathways related to carbohydrate, amino acid, and organic acid salt metabolism. Additionally, 62 DEGs in S. Typhimurium N25 were significantly enriched in five upregulated pathways (bacterial chemotaxis, bacterial invasion of epithelial cells, Salmonella infection, two-component system, and flagellar assembly). The results facilitate updated knowledge of the complex dynamics governing biofilms formation by S. Typhimurium and P. fluorescens, which provide a theoretical foundation for improved control strategies to ensure meat safety in the food industry.}, }
@article {pmid40022384, year = {2025}, author = {Chen, Y and Fan, X and Zhu, X and Xiao, J and Mu, Y and Wang, W and Wang, C and Peng, M and Zhou, M}, title = {Effects of luxS gene on biofilm formation and fermentation property in Lactobacillus plantarum R.}, journal = {Food research international (Ottawa, Ont.)}, volume = {203}, number = {}, pages = {115862}, doi = {10.1016/j.foodres.2025.115862}, pmid = {40022384}, issn = {1873-7145}, mesh = {*Biofilms/growth &amp; development ; *Lactobacillus plantarum/genetics/metabolism/physiology ; *Carbon-Sulfur Lyases/genetics/metabolism ; *Bacterial Proteins/genetics/metabolism ; *Fermentation ; *Quorum Sensing/genetics ; *Gene Expression Regulation, Bacterial ; Food Microbiology ; Homoserine/analogs &amp; derivatives/metabolism ; Lactones/metabolism ; }, abstract = {The biofilm formation of Lactobacilli is regulated by the LuxS/AI-2 quorum sensing (QS) system, but the mechanism of QS regulating the formation of Lactobacilli biofilm is not clear. This study aimed to investigate the mechanism of producing biofilm in L. plantarum R and its effect on the quality of fermented pickles based on LuxS/AI-2 QS system. Compared with L. plantarum R, the AI-2 activity of L. plantarum RΔluxS was significantly reduced, but the biofilm, extracellular protein, and eDNA were significantly increased. Moreover, expression of oppA, livJ, livH and comD genes was up-regulated and luxS, peg.3090 and peg.3093 was down-regulated. Results showed that peg.3093 was most significantly down-regulated in L. plantarum RΔluxS, and extremely significant negatively correlated with biofilm. The biofilm, eDNA, and extracellular protein of L. plantarum RΔpeg.3093 was higher than those of L. plantarum R. Moreover, metabolomics showed that deletion of luxS gene could decrease AI-2 level, promote anthocyanin and flavonol biosynthesis, lead to improving the antioxidant properties and quality of pickles. Thus, luxS gene knockout may increase biofilm by down-regulating the expression of peg.3093 to increase extracellular protein and eDNA. This study provides a theoretical basis for the enhancement of Lactobacillus biofilm and its application.}, }
@article {pmid40021740, year = {2025}, author = {Kim, Y and Kang, SM and Jo, KN and Roh, Y}, title = {Carbonate mineral precipitation induced by microorganisms enriched from the cave water and biofilm in a lime-decorated lava tube.}, journal = {Scientific reports}, volume = {15}, number = {1}, pages = {7182}, pmid = {40021740}, issn = {2045-2322}, support = {2022R1C1C2009540//National Research Foundation of Korea/ ; 2022R1A2C1005449//National Research Foundation of Korea/ ; }, mesh = {*Biofilms/growth &amp; development ; *Caves/microbiology ; *Calcium Compounds/chemistry ; *Oxides/chemistry ; *Calcium Carbonate/chemistry ; *Chemical Precipitation ; Bacteria ; Carbonates/chemistry ; Minerals/chemistry ; Magnesium/chemistry ; Strontium/chemistry ; Republic of Korea ; }, abstract = {Cave microorganisms associated with calcareous speleothems have been reported to facilitate calcium carbonate precipitation through crystal nucleation and mineral growth. In this study, we used carbonate-forming microorganisms enriched from cave water droplets and stalactite biofilm samples to induce precipitation of Mg[2+] or Sr[2+]-coprecipitated carbonate minerals and explored their mineralogical properties. The samples for these analyses were collected from Yongcheon Cave, a lime-decorated lava tube located on Jeju Island in South Korea. They included five soil and sediment samples from outside the cave, seven drip water samples from inside the cave, and nine biofilm samples swiped using sterilized cotton swabs from inside the cave. The microorganisms enriched from the drip water samples comprised bacterial genera, including Pseudomonas, Bacillus, Stenotrophomonas, Acinetobacter, and Morganella. which are known to contribute to carbonate formation. In contrast, the microorganisms enriched from the biofilms were dominated by Pseudomonas. When only Ca[2+] was present in the growth medium (Ca:Sr = 3:0), these microorganisms precipitated calcite and vaterite. Conversely, when Ca[2+] and Sr[2+] were present at varying ratios (Ca:Sr = 2:1, 1:1, and 1:2), calcian-strontianite was precipitated. Furthermore, when only Sr[2+] was present (Ca:Sr = 0:3), strontianite was formed. Adding Ca[2+] and Mg[2+] at varying ratios (Ca:Mg = 2:1, 1:1, and 1:2) led to the precipitation of magnesian-calcite and monohydrocalcite. When only Mg[2+] was added to the medium (Ca:Mg = 0:3), nesquehonite and struvite precipitated. These findings suggest that microorganisms enriched from the lava tube cave induce calcium carbonate precipitation through ureolysis and that Sr/Cr and Mg/Ca ratios influence the type of precipitated carbonate or phosphate minerals.}, }
@article {pmid40022258, year = {2025}, author = {Shang, L and Roffel, S and Slomka, V and D'Agostino, EM and Metris, A and Buijs, MJ and Brandt, BW and Deng, D and Gibbs, S and Krom, BP}, title = {An in vitro model demonstrating homeostatic interactions between reconstructed human gingiva and a saliva-derived multispecies biofilm.}, journal = {Microbiome}, volume = {13}, number = {1}, pages = {58}, pmid = {40022258}, issn = {2049-2618}, mesh = {Humans ; *Biofilms/growth &amp; development ; *Saliva/microbiology ; *Gingiva/microbiology ; *Coculture Techniques ; *Keratinocytes/microbiology/metabolism ; Bacteria/metabolism/classification/genetics ; Homeostasis ; RNA, Ribosomal, 16S/genetics ; Fibroblasts/microbiology ; Microbiota ; Cytokines/metabolism ; }, abstract = {BACKGROUND: In the oral cavity, host-microbe interactions (HMI) continuously occur and greatly impact oral health. In contrast to the well-studied disease-associated HMI during, for example, periodontitis, HMI that are essential in maintaining oral health have been rarely investigated, especially in a human-relevant context. The aim of this study was to extensively characterize homeostatic HMI between saliva-derived biofilms and a reconstructed human gingiva (RHG). RHG was reconstructed following the structure of native gingiva, composed of a multilayered epithelium formed by keratinocytes and a fibroblast-populated compartment. To mimic the oral environment, RHG were inoculated with pooled human saliva resuspended in different saliva substitute media and incubated for 2 or 4 days. The co-cultured biofilms were retrieved and characterized by viable bacterial counting and compositional profiling (16S rRNA gene sequencing). RHG was investigated for metabolic activity (MTT assay), tissue histology (hematoxylin and eosin staining), epithelial proliferation (Ki67 staining), antimicrobial peptide expression, and cytokine secretion.<br><br>RESULTS: Viable biofilms were detected up to day 4 of co-culturing. Bacterial counts indicated biofilm growth from the inoculation to day 2 and maintained thereafter at a similar level until day 4. All biofilms shared similar composition throughout 4&#xa0;days, independent of co-culture time and different saliva substitute media used during inoculation. Biofilms were diverse with Streptococcus, Haemophilus, and Neisseria being the dominating genera. While supporting biofilm development, RHG displayed no significant changes in metabolic activity, tissue histology, or epithelial proliferation. However, in the presence of biofilms, the antimicrobial peptides elafin and human &#x3b2;-defensin-2 were upregulated, and the secretion of cytokines IL-6, CXCL1, CXCL8, CCL5, and CCL20 increased.<br><br>CONCLUSION: This model mimicked homeostatic HMI where a healthy gingiva supported a viable, diverse, and stable microbial community, incorporating bacterial genera found on native gingiva. The gingiva model maintained its tissue integrity and exerted protective responses in the presence of biofilms over time. This study adds to the evidence that shows the important role of the host in maintaining homeostatic HMI that are essential for oral health. Video Abstract.}, }
@article {pmid40020861, year = {2025}, author = {Zhang, Y and Lu, X and Yu, S and Gu, H and Fei, X and Pan, T and Li, L and Ding, Y and Ni, M and Pan, Y}, title = {Study on the mechanisms of efficient phosphorus recovery by a pilot-scale biofilm sequencing batch reactor under low carbon demand.}, journal = {Environmental research}, volume = {}, number = {}, pages = {121204}, doi = {10.1016/j.envres.2025.121204}, pmid = {40020861}, issn = {1096-0953}, abstract = {To study the mechanism of a novel pilot-scale biofilm sequencing batch reactor (PS-BSBR) for efficient phosphorus recovery under low carbon demand. The phosphate uptake/release performance and carbon source utilization efficiency of PS-BSBR and a typical enhanced biological phosphate removal (EBPR) -A[2]O process were compared, and the detection methods of different phosphorus forms were improved. The results showed that phosphate uptake/release content of PS-BSBR were 3.07 times and 4.47 times of that of A[2]O process under high carbon source utilization efficiency, respectively. The PS-BSBR mainly used inorganic phosphorus (IP) in the form of non-apatite inorganic phosphorus (NAIP) in EPS (85-90%), which was dependent on the adsorption of biologically induced extracellular polymers (EPS). The A[2]O process was mainly based on the IP in the form of NAIP (60-70%) in the cell for phosphate uptake and release, that was, relying on the biological phosphorus metabolism in the cell of polyphosphate-accumulating organisms (PAOs). Macroomics sequencing revealed that PS-BSBR had a variety of PAOs and a high-abundance glycogen-accumulating organisms (GAOs). By up-regulating the expression of key genes related to cellular phosphorus metabolism and EPS secretion, PS-BSBR promoted the phosphorus metabolism of PAOs cells and the biologically induced phosphate adsorption and desorption, which were dominated by the synthesis and decomposition of EPS. Therefore, the phosphorus absorption and release performance of PS-BSBR process was significantly better than that of A[2]O process. This study could provide theoretical support and regulatory guidance for the application of PS-BSBR process in sewage phosphorus recovery under the consumption of low carbon sources.}, }
@article {pmid40017617, year = {2025}, author = {Scheithauer, TPM and Fernandes de Oliveira, IM and Ossendrijver, M and Dehay, E and van der Wurff, M and Rahaoui, H and Ballet, N and Keijser, BJF}, title = {Yeast cell wall derivatives as a potential strategy for modulating oral microbiota and dental plaque biofilm.}, journal = {Frontiers in oral health}, volume = {6}, number = {}, pages = {1543667}, pmid = {40017617}, issn = {2673-4842}, abstract = {INTRODUCTION: Derivatives from Saccharomyces cerevisiae yeast including yeast extracts and yeast cell walls are sustainable sources of valuable nutrients, including dietary fibers and proteins. Previous studies have shown that certain components from these yeast derivatives can inhibit the growth of harmful intestinal bacteria and promote the growth of beneficial bacteria. However, the effects of yeast derivatives on oral health have not yet been investigated.<br><br>METHODS: An in vitro oral biofilm model was employed to examine the impacts of yeast derivatives on the oral microbiota and their potential benefits for maintaining oral homeostasis. The model incorporated dental plaque donor material from both healthy and periodontitis diagnosed individuals. Biofilm formation, density, and microbial composition were quantified. Additionally, the production of short-chain fatty acids in the biofilm supernatants was measured.<br><br>RESULTS: Yeast extracts had only minor effects on oral biofilm formation. In contrast, yeast cell wall derivatives, which are rich in polysaccharides such as beta-glucans and mannans, significantly reduced the density of the oral biofilms in vitro. This reduction in biofilm density was associated with an overall shift in the bacterial community composition, including an increase in beneficial bacteria and a decrease in the abundance of Tannerella forsythia, an important species involved in bacterial coaggregation and the development and maturation of the oral biofilm. Furthermore, the yeast cell wall derivatives decreased the production of short-chain fatty acids, including acetic and butyric acid. These findings were consistent across both healthy and periodontitis microbiomes.<br><br>CONCLUSION: This study has demonstrated the potential of yeast cell wall derivatives to positively impact oral health by significantly reducing biofilm density, modulating the oral microbial composition, and decreasing the production of short-chain fatty acids. The observed effects highlight the promising applications of these yeast-based compounds as an approach to managing oral diseases. Further research is needed to fully elucidate the mechanisms of action and explore the clinical potential of yeast cell wall derivatives in promoting and maintaining oral health.}, }
@article {pmid40016146, year = {2025}, author = {Kim, D and Kim, JS and Bai, X and Zhang, J and Park, M and Lee, U and Lee, J and Bahn, YS and Xu, Y and Ha, NC}, title = {Development of Miniprotein-Type Inhibitors of Biofilm Formation in Candida albicans and Candida auris.}, journal = {Journal of microbiology and biotechnology}, volume = {35}, number = {}, pages = {e2411076}, doi = {10.4014/jmb.2411.11076}, pmid = {40016146}, issn = {1738-8872}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Antifungal Agents/pharmacology/chemistry ; *Molecular Dynamics Simulation ; *Candida albicans/drug effects/physiology ; *Candida auris/drug effects/genetics ; Microbial Sensitivity Tests ; Fungal Proteins/metabolism/antagonists &amp; inhibitors ; }, abstract = {Candida auris is a pathogenic fungus associated with high-mortality infections and forms resilient biofilms on various surfaces. In this study, we introduced a novel antifungal strategy against C. auris by integrating an AI-powered protein design tool, ProteinMPNN, with classical molecular dynamics (MD) simulations to design artificial proteins from a miniprotein library. This combined approach accelerated and enhanced the design process, enabling the rapid development of effective miniprotein inhibitors specifically targeting C. auris biofilm formation. The miniproteins developed in this study exhibited potent inhibitory effects on C. auris biofilms, representing a significant advancement in antifungal therapy. Notably, the combined application of these miniproteins enhanced suppression of biofilm formation. These findings highlight not only the strong therapeutic potential of these designed miniproteins but also the power of combining AI-driven protein design with MD simulations to advance biomedical research.}, }
@article {pmid40015993, year = {2025}, author = {Taniguchi, Y and Ouhara, K and Sato, Y and Shoji, M and Hou, Y and Zhai, R and Fujimori, R and Kuwahara, N and Tamura, T and Matsuda, S and Mizuno, N}, title = {Suppressive Effects of Kouboku on Methyl Mercaptan Production and Biofilm Formation in Porphyromonas gingivalis.}, journal = {Molecular oral microbiology}, volume = {}, number = {}, pages = {}, doi = {10.1111/omi.12493}, pmid = {40015993}, issn = {2041-1014}, support = {24K198800A 24K198811A//Encouragement of Young Scientists/ ; 24K198800A 24K198811A//Encouragement of Young Scientists/ ; 24K198800A 24K198811A//Encouragement of Young Scientists/ ; 22K099830A//Grants-in-Aid for Scientific Research/ ; 22K099830A//Grants-in-Aid for Scientific Research/ ; }, abstract = {Porphyromonas gingivalis, the bacterium responsible for periodontitis, produces several pathogenic factors, including methyl mercaptan, which contribute to the disease. Kouboku (Magnoliaceae), a Chinese herbal medicine, has been shown to suppress methyl mercaptan production from P. gingivalis. In this study, we investigated the inhibitory effect of Kouboku on methyl mercaptan production, biofilm formation, P. gingivalis-host cell interactions, and its potential synergistic antibacterial effect with antibiotics. Five standard and five clinically isolated P. gingivalis strains were evaluated. Methyl mercaptan production was measured using OralChroma. The mRNA expression of mgl and fimA, which are involved in methyl mercaptan synthesis and adhesion molecules, was assessed using quantitative PCR. Biofilm formation by P. gingivalis and epithelial cell adhesion were analyzed following treatment with or without Kouboku. Furthermore, the effects of the active ingredients of Kouboku, honokiol, and magnolol, on the minimum inhibitory concentrations (MICs) of antibiotics against P. gingivalis were determined. No significant differences were observed in the suppression of methyl mercaptan production among P. gingivalis strains with different FimA genotypes treated with Kouboku. Moreover, Kouboku inhibited biofilm formation in co-cultures of P. gingivalis and Fusobacterium nucleatum, as well as the adhesion of P. gingivalis to gingival epithelial cells through the downregulation of fimA. Treatment with honokiol and magnolol reduced the MICs of ampicillin, gentamicin, erythromycin, and tetracycline against P. gingivalis. These findings demonstrate that Kouboku affects P. gingivalis by modulating its adhesion to other bacteria and host cells, and enhances the antibacterial activity of certain antibiotics.}, }
@article {pmid40015968, year = {2025}, author = {Ali, P and Reeve, M and Carlson-Stadler, R and Vela, JD and Liu, L and Christenson, D and Shaw, A and Stadler, LB}, title = {Evaluation of biofilm scouring methods on the nitrification efficiency in a pilot-scale membrane-aerated biofilm reactor.}, journal = {Water environment research : a research publication of the Water Environment Federation}, volume = {97}, number = {3}, pages = {e70044}, doi = {10.1002/wer.70044}, pmid = {40015968}, issn = {1554-7531}, support = {//Water Environment Federation/ ; 1932000//NSF/ ; 931937//NSF/ ; }, mesh = {*Biofilms ; *Bioreactors ; *Nitrification ; Pilot Projects ; Membranes, Artificial ; Waste Disposal, Fluid/methods ; Nitrogen/chemistry/metabolism ; Water Purification/methods ; }, abstract = {Membrane-aerated biofilm reactors (MABRs) are being increasingly being implemented at full-scale for domestic wastewater treatment and effective biofilm control is critical to their performance. This study investigated the impact of three biofilm scouring strategies on nitrogen removal performance of a pilot-scale MABR operated in Houston, TX: (1) regular air scouring, (2) high intensity air scouring, and (3) high liquid flow scouring. Normal and high intensity air scouring regimes and a high liquid flow scour (10× baseline flow) were each tested sequentially. High NH4 [+]-N removal efficiency of 52% in flow-through mode was observed post-high liquid flow scouring, which was comparable to the performance during the intense scouring regime. The absolute abundance of amoA gene for ammonia oxidizing bacteria (AOB) increased significantly by over 200%, between pre- and post-high liquid flow scouring. The energy consumption was 43% lower for the combination of high liquid flow scouring with regular air scouring as compared to the intense air scouring. This study showed that high liquid flows may be utilized as an energy-efficient biofilm control strategy in nitrifying MABR systems. PRACTITIONER POINTS: Pilot-scale MABR reactors were operated with different scouring settings: regular aeration, intense aeration, and high liquid flow. High liquid flow scouring improved nitrification efficiency, comparable to intense scouring. High liquid flow scouring selected for nitrifiers as seen by an increase in AOB quantified as amoA gene abundance. Using high liquid flow with regular aeration scouring reduces electrical energy consumption by 43% as compared to intense aeration scouring. High liquid flows may be used as an energy-efficient biofilm control strategy to improve nitrification performance in MABR systems.}, }
@article {pmid40015666, year = {2025}, author = {Wang, X and Jiao, SY and Wang, J and Wu, RR and Zhang, TT and Wang, CM and Li, XJ}, title = {Description of three new Leptotrichia species isolated from dental biofilm: Leptotrichia rugosa sp. nov., Leptotrichia mesophila sp. nov. and Leptotrichia alba sp. nov.}, journal = {Anaerobe}, volume = {}, number = {}, pages = {102948}, doi = {10.1016/j.anaerobe.2025.102948}, pmid = {40015666}, issn = {1095-8274}, abstract = {Three bacterial strains, namely HSP-334[T], HSP-342[T] and HSP-536[T], were isolated from human oral dental biofilm. These strains were identified as Gram-stain-negative, straight or slightly curved anaerobes. Based on 16S rRNA genes analysis, strain HSP-334[T] exhibited the closest identity to Leptotrichia shahii LB37[T] (92.25%). Strain HSP-342[T] demonstrated the highest similarity to Leptotrichia hongkongensis HKU24[T] (98.03%), while strain HSP-536[T] displayed the greatest resemblance to Leptotrichia buccalis DSM 1135[T] (97.77%). Notably, the maximum sequence similarity among the three isolates ranged from 91.56% to 94.12%. All the phylogenies showed that strains HSP-334[T], HSP-342[T], HSP-536[T], all members of genus Leptotrichia and Pseudoleptotrichia goodfellowii JCM 16774[T] were clustered in one subclade within the family Leptotrichiaceae. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values calculated between these three strains and their phylogenetically related species were determined to be lower than the established species delineation threshold values. The major cellular fatty acids detected in these novel strains were C16:0 and C18:1ω7c. Strains HSP-334[T], HSP-342[T] and HSP-536[T] could be distinguished from each other by several phenotypic characteristics. Based on the comprehensive polyphasic taxonomic characterizations conducted, strains HSP-334[T], HSP-342[T] and HSP-536[T] represent three novel species of the genus Leptotrichia, for which the name Leptotrichia rugosa sp. nov. (type strain HSP-334[T] = JCM 36566[T] = CGMCC 1.18095[T] = MCCC 1K09354[T]), Leptotrichia mesophila sp. nov. (type strain HSP-342[T] = JCM 36567[T] = CGMCC 1.18052[T] = MCCC 1K09338[T]) and Leptotrichia alba sp. nov. (type strain HSP-536[T] = JCM 36662[T] = CGMCC 1.18096[T] = MCCC 1K09339[T]) are proposed.}, }
@article {pmid40015426, year = {2025}, author = {Sun, F and Jiao, Y and Liang, S and Zhuang, LL and Zhang, J}, title = {The Effect of Sulfamethoxazole on the Growth of Microalgae Biofilms and the Internal Transportation and Transformation of Nutrients in the Biofilm.}, journal = {Environmental research}, volume = {}, number = {}, pages = {121232}, doi = {10.1016/j.envres.2025.121232}, pmid = {40015426}, issn = {1096-0953}, abstract = {The resource recovery of nitrogen and phosphorus in wastewater can be realized based on microalgae biofilm cultivation. Antibiotic from wastewater could potentially transport along the microalgae biofilm and influence microalgae metabolism during the microalgae biofilm-based wastewater treatment technology. Therefore, how one typical antibiotic (sulfamethoxazole, SMX) transport inside algal biofilm was investigated in this study. Furtherly, the effects of SMX on the growth of Chlorella vulgaris and nutrients transfer dynamics along biofilm were studied by microelectrode, Raman spectroscopy and SEM-EDS. The results showed that 5 mg/L SMX could stimulate microalgae photosynthesis and increase the dry weight of microalgae biofilm by 28.56 % on the 30th day. At the same time, the algae density increased by 15.01 %. Sulfur element distribution showed that SMX accumulated 15 % ∼ 25 % more in the middle and bottom layers (40 μm ∼ 140 μm) than in the surface layer of the biofilm. SMX at the deeper layer stimulated the utilization of nitrogen, accelerating the uneven distribution of nitrogen (117 % ∼ 162 % more than the surface layer). 5mg/L SMX extended the effective photosynthetic region near the surface layer by 40 μm. This change intensified the chemical composition differences between the surface and bottom layers. The correlation analysis showed that nitrogen might be the key factor limiting the growth of microalgae biofilm. This study proved the positive effects of 5 mg/L SMX on microalgae biofilm growth, providing theoretical support for the application of microalgae biofilm technology in antibiotic treatment.}, }
@article {pmid40014816, year = {2024}, author = {Dubois, V&#xc1; and Salgado, PA and Molgatini, SL and Gliosca, LA}, title = {Subgingival biofilm colonization by Candida albicans and Candida dubliniensis in patients living with HIV from Buenos Aires, Argentina.}, journal = {Acta odontologica latinoamericana : AOL}, volume = {37}, number = {3}, pages = {191-202}, doi = {10.54589/aol.37/3/191}, pmid = {40014816}, issn = {1852-4834}, support = {01-02-18//Facultad de Odontolog&#xed;a de la Universidad de Buenos Aires, Programa de apoyo a la Investigaci&#xf3;n Integrada CONVOCATORIA 2019 -2024/ ; UBACYT 20720160100002BA//University of Buenos Aires/ ; }, mesh = {Humans ; *Biofilms ; Male ; *Candida albicans/isolation &amp; purification ; Adult ; Female ; *HIV Infections/microbiology/complications ; Argentina ; Candida/isolation &amp; purification ; Gingiva/microbiology ; Middle Aged ; Candidiasis, Oral/microbiology ; Cross-Sectional Studies ; }, abstract = {UNLABELLED: Oropharyngeal candidiasis (OC) is common among people living with HIV (PLWH). Persistent colonization of oral epithelial surfaces serves as an ecological niche for opportunistic pathogens and is a significant predisposing factor for OC development in PLWH. Mucosal colonization can lead to biofilm formation, directly impacting oral epithelium.<br><br>AIM: To assess Candida albicans and Candida dubliniensis colonization in subgingival biofilms of people living with HIV (PLWH) and undergoing antiretroviral therapy (ART).<br><br>MATERIALS AND METHOD: A sample of 51 PLWH who were receiving ART was studied, focusing on dental and periodontal parameters. Subgingival biofilm and mucosa samples were collected, and Candida spp. were identified using molecular techniques.<br><br>RESULTS: Men (average age: 41.11 &#xb1; 8.63) predominated. The main cause of HIV was sexual transmission. Fungal-related opportunistic diseases were observed in 18 patients, and LT CD4 counts were evaluated. A total 255 samples were collected, including 204 from gingivoperiodontal sites and 51 from oral mucosa. Candida spp. was detected in 55% of patients, with particular distribution patterns. Positive Candida spp. presence correlated with clinical attachment level and HIV treatments. Microscopic identification revealed the presence of hyphae at the time of microbiological sample collection. Molecular identification confirmed 16 Candida albicans and 36 Candida dubliniensis isolates, challenging their diagnostic importance.<br><br>CONCLUSIONS: The presence of yeast hyphae/pseudohyphae in subgingival biofilms indicates their role in gingivo-periodontal disease dysbiosis. PLWH in this Argentine region face challenges including limited access to healthcare. The study underscores the need for early oral health intervention, emphasizing the diagnostic significance of Candida.}, }
@article {pmid40014067, year = {2025}, author = {Kaur, J and Lather, A and Cheema, PS and Jangir, BL and Manoj, J and Singh, M and Joshi, VG and Chhabra, R}, title = {Designing, Synthesis and In Vitro Antimicrobial Activity of Peptide Against Biofilm Forming Methicillin Resistant Staphylococcus aureus.}, journal = {Current microbiology}, volume = {82}, number = {4}, pages = {159}, pmid = {40014067}, issn = {1432-0991}, mesh = {*Biofilms/drug effects ; *Methicillin-Resistant Staphylococcus aureus/drug effects/physiology ; Animals ; *Microbial Sensitivity Tests ; Mice ; Vero Cells ; *Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; Chlorocebus aethiops ; Antimicrobial Peptides/pharmacology/chemistry/chemical synthesis ; Hydrogen-Ion Concentration ; Staphylococcal Infections/microbiology/drug therapy ; Humans ; Drug Design ; }, abstract = {Increasing antimicrobial resistance and residue in an ecosystem is a huge threat to human as well as animal possibly inviting an uncontrollable outbreak and spoiling food. Use of alternative approaches in tackling the resistance problem has shown promising results in recent past. The present study was targeted to develop and evaluate the use synthetic peptide against biofilm forming methicillin resistant Staphylococcus aureus (MRSA). Peptide evaluation included determination of MIC, time kill kinetics, lysis activity, cell cytotoxicity assay, effect on biofilm formation, mechanism of action, thermo-stability and pH stability. Initially, a synthetic antimicrobial peptide, RWWKARIRL (ANLP-V3) was designed using bioinformatics tools and synthesized by solid phase synthesis using Fmoc chemistry. Peptide was found to exhibit antibacterial activity at 19.5 µg/mL concentration against both ATCC &amp; clinical isolates of S. aureus. The time kill kinetic studies revealed > 99% inhibition of growth after 3 h at MIC, whereas 100% cell inhibition was seen at 2 h at 2 × MIC and 4 × MIC. No cytotoxicity was observed against mice RBCs as well as Vero cells at 2 × MIC. The AMP was found to be thermo-stable as well as pH stable at a wide range. Field emission scanning electron microscopy study demonstrates cell morphological alterations in AMP treated cells indicating membrane interacting nature of AMP. At MIC concentration, effective inhibition of biofilm formation in ATCC strains was seen. In conclusion, designed peptide might be effective antimicrobial agent against methicillin resistant biofilm forming S. aureus underlining possibilities of its preclinical development against mastitis in dairy animals.}, }
@article {pmid40012871, year = {2025}, author = {Wu, X and He, F and Xu, X and Wu, L and Rong, J and Lin, S}, title = {Environmental Health and Safety Implications of the Interplay Between Microplastics and the Residing Biofilm.}, journal = {Environment &amp; health (Washington, D.C.)}, volume = {3}, number = {2}, pages = {118-132}, pmid = {40012871}, issn = {2833-8278}, abstract = {The increasing prevalence of microplastics in the environment has raised concerns about their potential environmental and health implications. Biofilms readily colonize microplastics upon their entry into the environment, altering their surface characteristics. While most studies have explored how biofilms influence the adsorption and transportation of other contaminants by microplastics, the reciprocal interplay between microplastics and biofilms and the resulting ecological risks remain understudied. This review comprehensively reviews the impact of microplastic properties on biofilm formation and composition, including the microbial community structure. We then explore the dynamic interactions between microplastics and biofilms, examining how biofilms alter the physicochemical properties, migration, and deposition of microplastics. Furthermore, we emphasize the potential of biofilm-colonized microplastics to influence the environmental fate of other pollutants. Lastly, we discuss how biofilm-microplastic interactions may modify the bioavailability, biotoxicity, and potential health implications of microplastics.}, }
@article {pmid40012443, year = {2025}, author = {Meng, X and Liu, Q and Wang, X and Han, X and Zhang, Q and Hu, HY}, title = {An Activatable Long-Fluorescence-Lifetime Probe for Exploring the Dual Function of StrH in Biofilm Formation and Necroptosis.}, journal = {Advanced healthcare materials}, volume = {}, number = {}, pages = {e2404252}, doi = {10.1002/adhm.202404252}, pmid = {40012443}, issn = {2192-2659}, support = {2021-I2M-1-054//Chinese Academy of Medical Sciences Initiative for Innovative Medicine/ ; 2242025//Natural Science Foundation of Beijing Municipality/ ; 22122705//National Natural Science Foundation of China/ ; 22277143//National Natural Science Foundation of China/ ; 22077139//National Natural Science Foundation of China/ ; }, abstract = {Streptococcus pneumoniae infections, particularly those associated with biofilm formation, pose significant therapeutic challenges due to their increased resistance to antibiotics and immune evasion. Identifying new biomarkers is crucial for accurate diagnosis and the development of innovative treatment strategies. StrH is recognized as a key enzyme in S. pneumoniae carbohydrate metabolism, however, its specific role in biofilm formation and its interactions with the host remain poorly understood. In this study, a highly sensitive and selective turn-on long-lifetime fluorescence probe, "HBT-PXZ-St," is designed to detect StrH activity and to reveal its functions. Using fluorescence lifetime imaging microscopy (FLIM), "HBT-PXZ-St" can quantify StrH activity and image live S. pneumoniae cells, achieving a fluorescence lifetime of ≈2 µs, which effectively minimizes background short-lived fluorescence interference. Additionally, the findings suggest that StrH activity significantly contributes to biofilm development and induces necroptosis in A549 host cells via the receptor-interacting serine/threonine-protein kinase 1 (RIPK1) pathway, thereby promoting bacterial colonization and invasion. This study provides insight into StrH's dual role as both a "sword and shield" during colonization and invasion, suggesting its potential as a therapeutic target for novel treatments against S. pneumoniae infections.}, }
@article {pmid40011382, year = {2025}, author = {Yuksekdag, Z and Kilickaya, R and Kara, F and Acar, BC}, title = {Biogenic-Synthesized Silver Nanoparticles Using the Ligilactobacillus salivarius KC27L Postbiotic: Antimicrobial, Anti-Biofilm, and Antioxidant Activity and Cytotoxic Effects.}, journal = {Probiotics and antimicrobial proteins}, volume = {}, number = {}, pages = {}, pmid = {40011382}, issn = {1867-1314}, abstract = {This study aimed to synthesize silver nanoparticles (AgNPs) using the postbiotic of the Ligilactobacillus salivarius KC27L strain and evaluate their multifunctional biological properties. The use of L. salivarius, a probiotic bacterium known for its ability to produce a wide range of metabolites, plays a crucial role in this process by acting as a natural, eco-friendly reducing, and stabilizing agent during AgNP synthesis. This approach not only eliminates the need for hazardous chemicals typically used in nanoparticle synthesis but also enhances the biocompatibility and biological efficacy of the resulting nanoparticles. Synthesized AgNPs were analyzed by Fourier transform infrared spectroscopy, FTIR (metabolites of postbiotic); UV-vis (peak of 435 nm); scanning electron microscope, SEM; transmission electron microscopy, TEM (spherical shapes, sizes < 50 nm), energy-dispersive spectrometry, EDS (peak at 3 keV); and zeta potential (- 18.6 mV). These nanoparticles (0.156-40 mg/mL) were evaluated for the antimicrobial and anti-biofilm activities against Escherichia coli ATCC 11229, Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 25923, Staphylococcus epidermidis ATCC 35984, and Streptococcus mutans ATCC 25175, and antioxidant activities using four different methods (2,2-diphenyl-1-picrylhydrazyl free radical scavenging, metal ion chelating, hydroxyl radical scavenging, and superoxide anion scavenging activities). Also, the cytotoxic activity was investigated against a normal cell line (L929) for 24, 48, and 72 h. At a concentration of 40 mg/mL, the AgNPs demonstrated the highest antimicrobial efficacy, with inhibition zones measured as 14.9 mm for P. aeruginosa, 9.5 mm for E. coli, 15.7 mm for S. epidermidis, and 12.9 mm for S. mutans. The AgNPs exhibited anti-biofilm activities against all Gram-positive and Gram-negative bacteria strains studied. According to the DPPH method, the highest antioxidant activity was determined at 40 mg/mL AgNP concentration (80.93%). AgNPs were found to have no toxic effect at low concentrations (0.39-25 µg/mL). Biogenic synthesized AgNPs could be used in biotechnological applications (biomaterials, health, environmental, etc.) with antibacterial, anti-biofilm, antioxidant, and nontoxic properties. However, further research is needed to understand the mechanisms of action of the particles fully.}, }
@article {pmid40011295, year = {2025}, author = {Yang, P and Huo, Y and Yang, Q and Zhao, F and Li, C and Ju, J}, title = {Synergistic anti-biofilm strategy based on essential oils and its application in the food industry.}, journal = {World journal of microbiology &amp; biotechnology}, volume = {41}, number = {3}, pages = {81}, pmid = {40011295}, issn = {1573-0972}, support = {32202192//The National Natural Science Foundation of China/ ; tsqn202211195//The special fund for Taishan Scholars project/ ; }, mesh = {*Biofilms/drug effects ; *Oils, Volatile/pharmacology ; *Food Industry ; *Quorum Sensing/drug effects ; *Anti-Bacterial Agents/pharmacology ; *Drug Synergism ; Bacteria/drug effects ; Food Microbiology ; }, abstract = {The microbial biofilm can induce a variety of food safety problems, and cause huge economic losses. Essential oils (EOs) not only have broad-spectrum antibacterial activity but also have a good ability to inhibit biofilm. However, the addition dose of EOs in practical application usually exceeds their flavor threshold, resulting in the appearance of undesired flavor. Therefore, synergistic antimicrobial may be a potential strategy to improve the antibacterial activity of EOs and to reduce their dosage. This paper focuses on the analysis of the synergistic anti-biofilm strategies based on EOs. Based on these, the action mechanism of EOs against biofilm and other commonly used anti-biofilm strategies in the food industry are summarized. The anti-biofilm mechanism of EOs is mainly related to inhibiting the synthesis of extracellular polysaccharides and proteins, destroying biofilm structure, inhibiting the metabolic activity of biofilm, inhibiting quorum sensing (QS) and regulating the formation of biofilm and the expression of toxicity-related genes. At present, the commonly used anti-biofilm strategies in the food industry mainly include physical strategies, chemical strategies and biological strategies, among which the combined application of different strategies is the future development trend. In particular, the synergistic anti-biofilm strategy based on EOs has shown great application value in the food industry. To sum up, some new information in this paper will give guidance and provide more reference for the development of efficient biofilm regulation strategies in future.}, }
@article {pmid40010280, year = {2025}, author = {Buakaew, T and Ratanatamskul, C}, title = {Enhanced pharmaceutical removal from building wastewater by the novel integrated system of anaerobic baffled biofilm-membrane bioreactor and UV/O3: Microbial community, occurrence of bio-intermediates and post-treatment.}, journal = {Journal of environmental management}, volume = {377}, number = {}, pages = {124657}, doi = {10.1016/j.jenvman.2025.124657}, pmid = {40010280}, issn = {1095-8630}, abstract = {This research aimed to develop the novel integrated system of anaerobic baffled biofilm-membrane bioreactor (AnBB-MBR) (with and without microaeration) and UV/O3 for removal of target pharmaceuticals (ciprofloxacin (CIP), caffeine (CAF), sulfamethoxazole (SMX) and diclofenac (DCF)) from building wastewater. The investigation was performed to elucidate how microaeration affected the removal performances, degradation kinetics and pathways of bio-intermediates of the AnBB-MBR. Two AnBB-MBR reactors - R1: AnBB-MBR (without microaeration) and R2: AnBB-MBR with microaeration at 0.93 LO2/LFeed - were operated at the same hydraulic retention time (HRT) of 30 h. The UV/O3 was selected as the post-treatment system. While UV alone slightly removed CIP without the removal of other compounds. After 150 min of the UV/O3, the R1 with UV/O3 achieved 97.31-100% removal efficiency of targeted pharmaceuticals and increased to 99.47-100% with the R2 integrated with UV/O3. The obtained pseudo-first order kinetic rate constants of the UV/O3 in treating the permeate of R1 were 0.0235, 0.004, 0.0423 and 0.097 min[-1] for CIP, CAF, SMX and DCF, respectively. Whereas the obtained pseudo-first order kinetic rate constants of the UV/O3 in treating the permeate of R2 were 0.021, 0.0338, 0.0511 and 0.0527 min[-1] for CIP, CAF, SMX and DCF, respectively. For the major microorganisms involved in targeted pharmaceutical removal in the R2 under microaerobic conditions included ammonia oxidizing bacteria (AOB) and methanotrophs, while Bacillus, Longilinea, Clostridium and Lactivibrio were possibly responsible for pharmaceutical removal in the R1 under anaerobic conditions. The differences of bio-intermediates between anaerobic and microaerobic conditions were exclusively identified. In addition, the integration of AnBB-MBR with microaeration and UV/O3 was more effective in removing a wide variety of bio-intermediates than the case of the integrated system without microaeration. Therefore, the integrated system of AnBB-MBR with microaeration and UV/O3 can be a promising technology for pharmaceutical removal from building wastewater.}, }
@article {pmid40010273, year = {2025}, author = {Wang, YY and Luo, BZ and Li, CM and Liang, JL and Liu, Z and Chen, WM and Guo, JL}, title = {Discovery of 3-hydroxypyridin-4(1H)-ones ester of ciprofloxacin as prodrug to combat biofilm-associated Pseudomonas aeruginosa.}, journal = {European journal of medicinal chemistry}, volume = {289}, number = {}, pages = {117396}, doi = {10.1016/j.ejmech.2025.117396}, pmid = {40010273}, issn = {1768-3254}, abstract = {Chronic infections by Pseudomonas aeruginosa (P. aeruginosa) are frequently complicated due to its ability to form biofilm, which also effectively enhance its resistance to antibiotics. Bacteria-specific antibiotic delivery could locally increase drug concentration to break antimicrobial resistance and reduce the drug's peripheral side effects. The standard-of-care drug ciprofloxacin suffers from severe systemic side effects and was therefore chosen for this approach. It has been identified that 3-hydroxypyridin-4(1H)-one as siderophore mimics could be utilized by P. aeruginosa, and reduced bacterial biofilm formation. In this work, ciprofloxacin was conjugated to 3-hydroxypyridin-4(1H)-one by cleavable linkers to yield prodrugs, which were strategically designed and synthesized to function as dual antibacterial and antibiofilm agents against P. aeruginosa. Conjugate 5c was identified and has the best minimum inhibitory concentrations of 1.07 μM against P. aeruginosa PAO1, and reduced 61.7 % of biofilm formation. In addition, 5c destroyed 75.7 % of mature biofilms. Further studies on the uptake mechanisms showed that the bacterial siderophore-dependent iron transport system was involved in the uptake of the conjugates. Conjugate 5c interfered with iron uptake by bacteria, inhibited their motilities and reduced the production of virulence. Furthermore, prodrug 5c reduced toxicity in vivo and in vitro and showed a positive therapeutic effect in the treatment of Caenorhabditis elegans (C. elegans) infected by P. aeruginosa. These results demonstrate that 3-hydroxypyridin-4(1H)-ones-ciprofloxacin prodrugs are potent in the treatment of biofilm-associated drug-resistant P. aeruginosa infections.}, }
@article {pmid40010214, year = {2025}, author = {Cheng, Y and Yu, Q and Zhang, W and Liu, Z and Ding, J and Pan, H and Li, Y and Wu, D and Zhu, M and Xie, X and Zhu, N}, title = {Diet dependent trophic transfer of nanoparticles (ZnO and TiO2) along the "photic biofilm-snail" food chain.}, journal = {Journal of hazardous materials}, volume = {489}, number = {}, pages = {137657}, doi = {10.1016/j.jhazmat.2025.137657}, pmid = {40010214}, issn = {1873-3336}, abstract = {Multispecies biofilm exhibited high resistance to nanotoxicity by secreting extracellular polymeric substances (EPS) and undergoing alterations in the community composition. Scarce information was available to assess how these changes could further influence the transfer of nanoparticles (NPs) through the biofilm-based food chain. Photic biofilm was exposed to two distinct NPs (ZnO and TiO2) and subsequently grazed by snails. Exposure to different NPs led to variations in biomass, chlorophyll content, EPS productivity, alpha diversity, and community composition of the photic biofilm. The presence of ZnO NPs facilitated the growth of phylum Cyanobacteria while TiO2 promoted EPS productivity of photic biofilm. EPS were capable of embedding NPs (TiO2 and ZnO) within its matrix, thereby mitigating their aggregation within the biofilm matrix. These alterations were subsequently confirmed to have an impact on the trophic transfer factors (TTF) of NPs through the constructed biofilm-snail food chain. The TTF of ZnO was lower than that of TiO2 in feeding scenario 1 (only fed on TiO2 or ZnO biofilm) but higher than that of TiO2 in feeding scenario 2 (fed on TiO2 and ZnO biofilm simultaneously), which was attributed to the shifts in the algae composition and a smaller size of ZnO NPs in EPS. This study demonstrated that the response of photic biofilm to NPs further affected the TTFs of NPs through the food chain.}, }
@article {pmid40010036, year = {2025}, author = {Maetens, L and Maiti, B and Cools, F and Verheye, S and Daelemans, D and Persoons, L and Temmerman, L and Kieswetter, A and Van der Eycken, EV and Coppola, GA and Vackier, T and Steenackers, HP}, title = {Optimizing biofilm inhibitors: Balancing activity and toxicity in 2N-aminated 5-aryl-2-aminoimidazoles.}, journal = {Bioorganic &amp; medicinal chemistry}, volume = {121}, number = {}, pages = {118115}, doi = {10.1016/j.bmc.2025.118115}, pmid = {40010036}, issn = {1464-3391}, abstract = {To evaluate the effect of amination on biofilm inhibition against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus, representative compounds of two previously described 5-aryl-2-aminoimidazole (5-Ar-2-AI) classes were aminated by installing an amino group at the end of the substituted n-alkyl chain. Amination led to an improvement in activity for one of the two classes, the 2N-substituted 5-Ar-2-AI class. Based on these findings, a more extensive library of 2N-substituted-aminated 5-Ar-2-AIs was synthesized having different n-alkyl and halogen substitutions on the 2N-position and the 4(5)-phenyl ring, respectively. Compounds were evaluated for their biofilm inhibitory activity against E. coli, P. aeruginosa, S. aureus, Staphylococcus epidermidis and MRSA. Additionally, their toxicity was tested on eight continuous cell lines, peripheral blood mononuclear cells and Caenorhabditis elegans, along with their genotoxicity on Capan-1. Halogenation and elongation of the n-alkyl substituent showed a positive effect on biofilm inhibitory activity, but also increased toxicity. Compromising between activity and toxicity, a non-halogenated 2N-substituted-aminated 5-Ar-2-AI compound with an intermediate n-heptyl substitution demonstrated promising broad-spectrum biofilm inhibition, making it a suitable candidate for further research in anti-infectious medical applications.}, }
@article {pmid40009776, year = {2025}, author = {Ghosh, A and Bhattacharya, T and Mandal, D and Dutta, K and Dey, S and Saha, K and Chattopadhyay, D}, title = {Synthesis of Yttria Nanoparticle-Loaded Electrospun Nanofibers for Enhanced Antimicrobial Activity, Biofilm Inhibition, and Alleviation of Diabetic Wounds.}, journal = {ACS applied bio materials}, volume = {}, number = {}, pages = {}, doi = {10.1021/acsabm.4c01818}, pmid = {40009776}, issn = {2576-6422}, abstract = {Diabetes-related sores and ulcers are quite common around the world and can cause complicated disruptions to both patient compliance and socioeconomic structure. Diabetic wounds take longer to heal due to pathophysiological causes, persistent infections, and increasingly severe medical problems. Nanoparticles (NPs) derived from nanotechnology have drawn interest due to their revolutionary potential in understanding the biological milieu and offering therapeutic strategies for wound healing. In this regard, the potential of yttrium oxide nanoparticles (YNPs) has been studied extensively to understand their efficacy in diabetic wound healing. Yttrium oxide nanoparticles having size in the range of 2-10 nm were prepared and incorporated into nanofibrous mats consisting of polyurethane as the matrix polymer, and leaf extract of Azadirachta indica and clindamycin hydrochloride as additive conventional antidiabetic and antibacterial agents to form S3. Physicochemical characterization tests confirmed the formation of nanofibers having average diameters in the range of 320-470 nm, respectively. The study demonstrated that S3 shows an enhanced zone of inhibition against E. coli (29 mm), S. aureus (32 mm), and P. aeruginosa (30 mm). Moreover, the nanofibrous mats also prevented microbial penetration and biofilm formation, as observed from MTT, CV, and confocal microscopy images. In vivo wound healing study conducted on diabetic mice revealed that S3 exhibited high wound contraction after 9 days of treatment. Additionally, the fabricated mat lowered plasma glucose levels, hepatotoxicity, and oxidative stress biomarkers. Therefore, it can be concluded that YNP-loaded nanofibrous composite mats have a strong potential in alleviating diabetic wounds.}, }
@article {pmid40008876, year = {2025}, author = {Borralho, J and Handem, S and Lança, J and Ferreira, B and Candeias, C and Henriques, AO and Hiller, NL and Valente, C and Sá-Leão, R}, title = {Inhibition of pneumococcal growth and biofilm formation by human isolates of Streptococcus mitis and Streptococcus oralis.}, journal = {Applied and environmental microbiology}, volume = {}, number = {}, pages = {e0133624}, doi = {10.1128/aem.01336-24}, pmid = {40008876}, issn = {1098-5336}, abstract = {UNLABELLED: In a world facing the unprecedented threat of antibiotic-resistant bacteria, targeted approaches to control colonization and prevent disease caused by common pathobionts offer a promising solution. Streptococcus pneumoniae (pneumococcus) is a leading cause of infections worldwide, affecting both children and adults despite available antimicrobials and vaccines. Colonization, which occurs in the form of a biofilm in the upper respiratory tract, is frequent and a prerequisite for disease and transmission. The use of live bacterial strains as biotherapeutics for infectious diseases is actively being explored. Here, we investigated the potential of commensal streptococci to control S. pneumoniae. Screening of over 300 human isolates led to the identification of seven strains (one Streptococcus oralis and six Streptococcus mitis, designated A22 to G22) with inhibitory activity against S. pneumoniae of multiple serotypes and genotypes. Characterization of A22 to G22 cell-free supernatants indicated the involvement of secreted proteins or peptides in the inhibitory effect of all S. mitis isolates. Genome analyses revealed the presence of 64 bacteriocin loci, encoding 70 putative bacteriocins, several of which are novel and absent or rare in over 7,000 publicly available pneumococcal genomes. Deletion mutants indicated that bacteriocins partially or completely explained the anti-pneumococcal activity of the commensal strains. Importantly, strains A22 to G22 were further able to prevent and disrupt pneumococcal biofilms, a proxy for nasopharyngeal colonization. These results highlight the intricacy of the interactions among nasopharyngeal colonizers and support the potential of strains A22 to G22 to be used as live biotherapeutics, alone or in combination, to control S. pneumoniae colonization.<br><br>IMPORTANCE: Streptococcus pneumoniae (pneumococcus) infections remain a major public health issue despite the use of vaccines and antibiotics. Pneumococci asymptomatically colonize the human upper respiratory tract, a niche shared with several commensal Streptococcus species. Competition for space and nutrients among species sharing the same niche is well documented and tends to be more intense among closely related species. Based on this rationale, a screening of several commensal streptococci isolated from the human upper respiratory tract led to the identification of strains of Streptococcus mitis and Streptococcus oralis capable of inhibiting most pneumococcal strains, across diverse serotypes and genotypes. This inhibition was partially or wholly linked to the expression of novel bacteriocins. The selected S. mitis and S. oralis strains significantly disrupted pneumococcal biofilms, indicating a potential for using commensals as biotherapeutics to control pneumococcal colonization, a key step in preventing disease and transmission.}, }
@article {pmid40008875, year = {2025}, author = {Reiche, T and Hageskal, G and Mares, M and Hoel, S and Tøndervik, A and Heggeset, TMB and Haugen, T and Sperstad, SB and Trøen, HH and Bjørkøy, S and Jakobsen, AN}, title = {Shifts in surface microbiota after cleaning and disinfection in broiler processing plants: incomplete biofilm eradication revealed by robotic high-throughput screening.}, journal = {Applied and environmental microbiology}, volume = {}, number = {}, pages = {e0240124}, doi = {10.1128/aem.02401-24}, pmid = {40008875}, issn = {1098-5336}, abstract = {Broiler processing environments are a source of spoilage bacteria and potential pathogens. The aim of this study was to investigate the impact of cleaning and disinfection (C&amp;D) on bacterial load and diversity in two broiler processing plants and to determine the efficacy of industry-standard disinfectants (DIs). C&amp;D significantly reduced average bacterial loads on surfaces from 3.7 to 1.8 log CFU/cm[2] in Plant A and from 7.0 to 3.8 log CFU/cm[2] in Plant B (P < 0.001). Metataxonomics revealed that Acinetobacter and an unknown Enterobacteriaceae genus dominated before C&amp;D in Plants A and B, respectively, while Pseudomonas was predominant after C&amp;D in both plants. Bacterial diversity only declined significantly after C&amp;D in Plant B. Bacterial loads also declined across hygienic zones along the broiler processing line in Plant A. During slaughter, Staphylococcus, Lactobacillus, and Anoxybacillus dominated, and bacterial loads were significantly higher compared with post-slaughter zones, which were dominated by Pseudomonas. Culture-dependent analyses confirmed the presence of Pseudomonas spp. and also bacteria affecting food safety, including Listeria monocytogenes, Escherichia coli, Yersinia enterocolitica, Acinetobacter baumannii, and Pseudomonas aeruginosa. A selection of these was tested against DIs using robotic high-throughput screening. At the recommended user concentrations, DIs effectively inhibited planktonic bacteria and significantly reduced mono-species biofilms. However, none of the DIs completely eradicated all biofilms at these concentrations, with survival rates ranging from 7% to 53%, depending on the DI. In conclusion, C&amp;D effectively reduces the bacterial burden and reshapes the bacterial microbiota with incomplete biofilm eradication by commercial DIs.IMPORTANCEBroiler meat continues to be involved in bacterial disease outbreaks. The surface microbiota in broiler processing environments can be a source of contaminating bacteria. Our study highlights the importance of effective C&amp;D routines since potential pathogens and spoilage bacteria are found in these environments. Furthermore, the study provides evidence of biofilms surviving high concentrations of industry-standard DIs. This emphasizes the importance of additional measures to facilitate biofilm removal, such as mechanical cleaning, but also suggests that there is a need for DIs with stronger biofilm eradication capabilities. Ultimately, it is important to understand and continuously improve the state of hygiene in broiler processing plants to mitigate the risk of foodborne disease outbreaks.}, }
@article {pmid40008689, year = {2025}, author = {Rodrigues, RS and Carvalho, AG and Silva, MEP and Ramos, IVG and Lima, NCS and Esquerdo, RP and Belém, MGL and Taborda, RLM and Carvalho-Assef, APD and Matos, NB}, title = {Antibiotic resistance and biofilm formation in Klebsiella spp. isolates from Intensive Care Units in the Brazilian Amazon.}, journal = {Brazilian journal of biology = Revista brasleira de biologia}, volume = {84}, number = {}, pages = {e286461}, doi = {10.1590/1519-6984.286461}, pmid = {40008689}, issn = {1678-4375}, mesh = {*Biofilms/drug effects ; *Intensive Care Units ; *Klebsiella/drug effects/isolation &amp; purification/physiology ; Humans ; Brazil ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; *beta-Lactamases ; Drug Resistance, Bacterial ; }, abstract = {Klebsiella spp. is an opportunistic pathogen which poses a significant threat to public health, especially due to antimicrobial resistance and biofilm formation. This study aimed to determine the antibiotic resistance profile, biofilm formation and β-lactamases production in Klebsiella spp. strains from clinical samples obtained from hospitalized patients, health professionals and hospital environment of intensive care units (ICUs) in Brazilian Amazon. The strains were obtained from clinical samples in different hospitals and identified using molecular techniques. The antimicrobial susceptibility was investigated via disk diffusion and microdilution. Biofilm formation was evaluated using a microtiter plate assay, while the extended-spectrum β-lactamases (ESBL) and carbapenemases production was assessed via disk approximation tests and combined disk tests, respectively. A total of 226 Klebsiella spp. strains were identified, with 141 coming from patients hospitalized in ICUs, 54 from healthcare workers, and 31 from hospital structures. Collection sites that showed the highest frequencies of isolated bacteria were the armpit (43,3%), oral cavity (42.6%), nasal cavity (70.4%), beds (54.8%) and mechanical ventilation (19.4%). Klebsiella spp. isolates from hospitalized patients and hospital ICU environments showed a high frequency of resistance (>50%) to the antibiotics, cefuroxime, cefotaxime, ceftriaxone, ciprofloxacin and aztreonam, and greater sensitivity (>70%) to carbapenems, amikacin and polymyxin B. Samples obtained from hospital structures (74.2%) and patients (51.8%) exhibited a high rate of multidrug resistant (MDR) isolates. In addition, 29% of Klebsiella isolates were found to produce ESBL and 15.5% carbapenemases. Biofilm formation was observed in 58.4% (132/226) of the isolates, with percentages of 64.5% (91/141) in hospitalized patients, 51.6% (16/31) on hospital structures, and 46.3% (25/54) among healthcare professionals. These results indicated a high percentage of antibiotics resistance and MDR in isolates from hospital structures and patients, which also showed ability to produce biofilms, ESBL and carbapenemases. Our findings reinforce the need to monitor resistance and adopt measures aimed at preventing the spread of MDR bacteria in ICUs.}, }
@article {pmid40008293, year = {2025}, author = {Volk, M and Šavli, D and Molan, K and Terlep, S and Levičnik-Höfferle, &#x160; and Trost, M and Gašpirc, B and Lukač, M and Jezeršek, M and Stopar, D}, title = {Er:YAG laser biofilm removal from zero-gap periodontal/peri-implant model system mimicking clinical attachment loss.}, journal = {Journal of biomedical optics}, volume = {30}, number = {2}, pages = {025002}, pmid = {40008293}, issn = {1560-2281}, mesh = {*Biofilms ; *Lasers, Solid-State ; *Dental Implants/microbiology ; Titanium/chemistry ; Humans ; Photoacoustic Techniques/methods ; Dimethylpolysiloxanes/chemistry ; Models, Biological ; }, abstract = {SIGNIFICANCE: Here, we present a photoacoustic method to remove biofilms from periodontal and peri-implant-constrained geometries.<br><br>AIM: We aim to remove biofilms from narrow periodontal and peri-implant model systems with the application of Er:YAG ultrashort laser pulses.<br><br>APPROACH: Construction of zero-gap model system from PDMS and titanium, growth of biofilms on titanium surfaces, and removal of biofilms with Er:YAG USP, 20 mJ, 15&#xa0;Hz, and 10&#xa0;s were performed.<br><br>RESULTS: The results suggest that geometry, the vertical position of the laser fiber tip, and the evolution of the primary cavitation bubble significantly affect cleaning effectiveness. Cleaning was higher in the wedge part of the model system. In the zero-gap part of the model system, biofilm cleaning effectiveness was highest at the position of the laser fiber tip and decreased above and below the fiber tip. The dimension of the space in which the cavitation bubble develops determines the size and dynamics of the expanded cavitation bubble and consequently the biofilm cleaning effectiveness.<br><br>CONCLUSIONS: The obtained results suggest a very good biofilm removal effectiveness in difficult-to-reach narrow geometries mimicking clinical attachment loss in the periodontal/peri-implant pocket.}, }
@article {pmid40008271, year = {2025}, author = {Martin, A and Doyle, N and O'Mahony, TF}, title = {Sodium dichloroisocyanurate: a promising candidate for the disinfection of resilient drain biofilm.}, journal = {Infection prevention in practice}, volume = {7}, number = {1}, pages = {100446}, pmid = {40008271}, issn = {2590-0889}, abstract = {BACKGROUND: Biofilms are complex multicellular communities of microorganisms embedded within a protective matrix which confers resistance to various antimicrobials, including biocides. Biofilms can cause a range of human diseases and are responsible for 1.7 million hospital-acquired infections in the US annually, providing an economic burden of $11.5 billion in treatment costs. Biofilm contained within drain and plumbing systems may contain pathogenic viruses and bacteria which pose a significant risk to patient safety within healthcare environments.<br><br>AIM: The aim of this study was to determine if three hospital-grade disinfectants (sodium dichloroisocyanurate, peracetic acid and sodium hypochlorite) were capable of killing microorganisms within biofilm, and thus, determining their potential as candidates for drain biofilm disinfection.<br><br>METHODS: Pseudomonas aeruginosa biofilms were cultivated using the CDC biofilm reactor, a standardised method for determining disinfectant efficacy against biofilm within the United States of America. Each disinfectant was tested using a one-minute contact time, using the highest concentration available on the product label.<br><br>FINDINGS: The sodium dichloroisocyanurate product was successful in killing biofilm microorganisms, resulting in a log reduction of &#x2265; 8.70. Peracetic acid reduced biofilm by 3.82 log10 units, followed by sodium hypochlorite, which produced a reduction of 3.78 log10 units.<br><br>CONCLUSIONS: The use of a highly effective disinfectant with proven biofilm efficacy can help ensure patient safety and reduce infection levels. Drains and plumbing systems provide a reservoir for potential pathogens and biofilm; thus, drain disinfection is critical in reducing the instance of hospital-acquired infections. Sodium dichloroisocyanurate may provide a reliable solution for drain applications and subsequently, patient wellbeing and safety.}, }
@article {pmid40008185, year = {2025}, author = {Robertsson, C and Davies, J and Svensäter, G and Nord, AB and Norrström, N and Wickström, C}, title = {MUC5B modulation of early oral biofilm glucose metabolism.}, journal = {Frontiers in oral health}, volume = {6}, number = {}, pages = {1516025}, pmid = {40008185}, issn = {2673-4842}, abstract = {INTRODUCTION: Salivary mucin MUC5B has been suggested to support eubiosis in early oral biofilms by regulating the attachment of commensals, while downregulating dysbiotic activities related to dental caries development, such as microbial carbohydrate transport and metabolism.<br><br>METHODS: To investigate how the metabolism of glucose, a potential driver for dental caries, in early mono- and dual-species biofilms of oral Actinomyces naeslundii and Streptococcus gordonii clinical isolates was affected by the presence of the complex salivary mucin MUC5B, this study employed nuclear magnetic resonance (NMR)-based metabolomics with the interpretation of network integration.<br><br>RESULTS AND DISCUSSION: MUC5B reduced early attachment in the presence of glucose compared with uncoated surfaces but maintained even species distribution. This suggests that MUC5B may represent an innate mechanism to regulate biofilm eubiosis by supporting early coadhesion while regulating total biomass. All annotated metabolites were intermediates in either carbohydrate metabolism, pyruvate conversion, or amino acid metabolism, which was not unexpected in biofilm glucose metabolomes from two saccharolytic species since pyruvate conversion represents a junction point between glycolysis and amino acid metabolic chains. The 10 metabolites present in all early biofilms represent a core metabolome shared by A. naeslundii and S. gordonii. Such core metabolomes can be used to detect deviations in future studies. Significant differences in metabolite abundance elicited by the presence of MUC5B were also detected. In early biofilms where they were each present, pyruvate, ethanol, and metabolite 134 were present in significantly higher abundance in the presence of 25% MUC5B with 20&#x2005;mM glucose (MUC5B&#x2009;+&#x2009;G) compared with a physiologic buffer with 20&#x2005;mM glucose (PBS&#x2009;+&#x2009;G), while metabolites 84, 97, and sarcosine were present at significantly lower abundance. Metabolite 72 was unique to biofilms grown in MUC5B&#x2009;+&#x2009;G, and eight unannotated metabolites were unique to biofilms grown in PBS&#x2009;+&#x2009;G. A pathway enrichment analysis of the metabolites that were differently expressed in early A. naeslundii, S. gordonii, and dual-species biofilms grown with 20&#x2005;mM glucose with or without MUC5B showed that pyruvate metabolism was significantly over-represented. Studying the metabolic interactions between commensal members of oral biofilms and modulatory effects of host factors such as glycoproteins in saliva during the metabolism of substrates that are potential drivers of dysbiosis, such as glucose, is essential to understand the roles of oral microbial ecosystems in oral health and disease.}, }
@article {pmid40007476, year = {2025}, author = {Li, Y and Wang, P and Liu, Y and Wu, X and Long, G and Chen, Y and Wang, J and Tong, F and Wang, X}, title = {Fe3O4-Based Nanospheres with High Photothermal Conversion Efficiency for Dual-Effect and Mild Biofilm Eradication against Periodontitis.}, journal = {ACS applied materials &amp; interfaces}, volume = {}, number = {}, pages = {}, doi = {10.1021/acsami.4c17966}, pmid = {40007476}, issn = {1944-8252}, abstract = {Periodontitis, a chronic inflammatory oral disease resulting from plaque biofilms, affects about 743 million individuals worldwide. However, the efficacy of current treatments is hampered by challenges in delivering antibiotics to recalcitrant oral biofilms and bacterial resistance, thereby impeding successful treatment of infectious diseases. To address the issues, an antibacterial photothermal material was designed, comprising a spherical structure of zinc oxide (ZnO) wrapped with triiron tetraoxide (Fe3O4). The outer layer of the material adsorbed epsilon-polylysine (EPL) by electrostatic action, ultimately leading to the fabrication of Fe3O4/ZnO/EPL nanoparticles (FZE NPs). The Fe3O4 core endowed the nanoparticles with efficient photothermal properties, facilitating the dispersion of dense biofilms, which dramatically promoted the adsorption and penetration of ZnO and EPL into the biofilms to effectively kill bacteria in biofilms in vitro with enhanced sterilization ability. Additionally, upon dissolution in aqueous media, EPL acts as a positively charged antimicrobial peptide that adsorbs onto the surface of negatively charged bacterial membranes, thereby effectively modulating inflammatory responses. In order to ascertain the efficacy of FZE NPs, an investigation was conducted into their antimicrobial effects against the periodontitis-associated pathogen Porphyromonas gingivalis (P. gingivalis) in vitro. Furthermore, the antiperiodontitis potential of FZE NPs was evaluated in Sprague-Dawley (SD) rats of ligamentous periodontitis. In addition, toxicity evaluations indicated that the material had an acceptable biosafety profile in vitro and in vivo. In summary, the nanospheres (FZE NPs) represent a promising therapeutic strategy for the treatment of periodontitis.}, }
@article {pmid40006756, year = {2025}, author = {Miranda, DG and Tomé, FM and Miguel, MMV and Liberato, SFDS and Marcucci, MC and Vigerelli, H and Rodrigues, FP and Pacheco-Soares, C and Godoi, BH and Carrouel, F and de Oliveira, LD and Ramos, LP}, title = {Gymnema sylvestre as a Potential Anti-Inflammatory and Anti-Biofilm Agent Against Anaerobic Infections: An In Vitro Study.}, journal = {Plants (Basel, Switzerland)}, volume = {14}, number = {4}, pages = {}, doi = {10.3390/plants14040497}, pmid = {40006756}, issn = {2223-7747}, abstract = {This study evaluates the antimicrobial activity of the glycolic extract of G. sylvestre against anaerobic pathogens, along with its cytotoxicity, genotoxicity, anti-inflammatory activity, antioxidant effects, and phytochemical composition. Phytochemical analysis was conducted using high-performance liquid chromatography and liquid chromatography-mass spectrometry, while the antioxidant effect was assessed through a DPPH assay. Antimicrobial action was tested on planktonic cultures and biofilms of Porphyromonas gingivalis, Porphyromonas endodontalis, Parvimonas micra, and Fusobacterium nucleatum. Cytotoxicity was evaluated using mouse macrophages (RAW 264.7), rat fibroblasts (L929), and human keratinocytes (HaCaT). Anti-inflammatory effects were measured by an immunoenzymatic assay (ELISA) on RAW 264.7 cells. Statistical analysis was performed using a one-way ANOVA and Tukey's test. Phytochemical analysis revealed the presence of phenolic compounds and flavonoids. The extract demonstrated a reduction of over 95% in biofilms of P. gingivalis, P. micra, and F. nucleatum within 5 min of treatment. Cell viability (HaCaT) remained above 80%. Antioxidant activity showed an EC50 of 353.43 µg/mL, achieving a 50% reduction in free radicals. A significant decrease in TNF-α (a pro-inflammatory cytokine) and an increase in IL-10 (an anti-inflammatory cytokine) were observed. In conclusion, the extract of G. sylvestre exhibits promising potential as a therapeutic agent for treating anaerobic infections, inflammation, and oxidative stress.}, }
@article {pmid40006039, year = {2025}, author = {Dzalamidze, E and Gorzynski, M and Vande Voorde, R and Nelson, D and Danelishvili, L}, title = {Discovery of Biofilm-Inhibiting Compounds to Enhance Antibiotic Effectiveness Against M. abscessus Infections.}, journal = {Pharmaceuticals (Basel, Switzerland)}, volume = {18}, number = {2}, pages = {}, doi = {10.3390/ph18020225}, pmid = {40006039}, issn = {1424-8247}, support = {1R15AI142609-01A1/AI/NIAID NIH HHS/United States ; }, abstract = {Background/Objectives: Mycobacterium abscessus (MAB) is a highly resilient pathogen that causes difficult-to-treat pulmonary infections, particularly in individuals with cystic fibrosis (CF) and other underlying conditions. Its ability to form robust biofilms within the CF lung environment is a major factor contributing to its resistance to antibiotics and evasion of the host immune response, making conventional treatments largely ineffective. These biofilms, encased in an extracellular matrix, enhance drug tolerance and facilitate metabolic adaptations in hypoxic conditions, driving the bacteria into a persistent, non-replicative state that further exacerbates antimicrobial resistance. Treatment options remain limited, with multidrug regimens showing low success rates, highlighting the urgent need for more effective therapeutic strategies. Methods: In this study, we employed artificial sputum media to simulate the CF lung environment and conducted high-throughput screening of 24,000 compounds from diverse chemical libraries to identify inhibitors of MAB biofilm formation, using the Crystal Violet (CV) assay. Results: The screen established 17 hits with ≥30% biofilm inhibitory activity in mycobacteria. Six of these compounds inhibited MAB biofilm formation by over 60%, disrupted established biofilms by ≥40%, and significantly impaired bacterial viability within the biofilms, as confirmed by reduced CFU counts. In conformational assays, select compounds showed potent inhibitory activity in biofilms formed by clinical isolates of both MAB and Mycobacterium avium subsp. hominissuis (MAH). Key compounds, including ethacridine, phenothiazine, and fluorene derivatives, demonstrated potent activity against pre- and post-biofilm conditions, enhanced antibiotic efficacy, and reduced intracellular bacterial loads in macrophages. Conclusions: This study results underscore the potential of these compounds to target biofilm-associated resistance mechanisms, making them valuable candidates for use as adjuncts to existing therapies. These findings also emphasize the need for further investigations, including the initiation of a medicinal chemistry campaign to leverage structure-activity relationship studies and optimize the biological activity of these underexplored class of compounds against nontuberculous mycobacterial (NTM) strains.}, }
@article {pmid40005975, year = {2025}, author = {Codru, IR and Vintilă, BI and Bereanu, AS and Sava, M and Popa, LM and Birlutiu, V}, title = {Antimicrobial Resistance Patterns and Biofilm Analysis via Sonication in Intensive Care Unit Patients at a County Emergency Hospital in Romania.}, journal = {Pharmaceuticals (Basel, Switzerland)}, volume = {18}, number = {2}, pages = {}, doi = {10.3390/ph18020161}, pmid = {40005975}, issn = {1424-8247}, abstract = {Background/Objectives: Ventilator-associated pneumonia (VAP) remains a critical challenge in ICU settings, often driven by the biofilm-mediated bacterial colonization of endotracheal tubes (ETTs). This study investigates antimicrobial resistance patterns and biofilm dynamics in ICU patients, focusing on microbial colonization and resistance trends in tracheal aspirates and endotracheal tube biofilms at a county emergency hospital in Romania. Methods: We conducted a longitudinal analysis of ICU patients requiring mechanical ventilation for more than 48 h. Tracheal aspirates and ETT biofilms were collected at three key time points: T1 (baseline), T2 (48 h post-intubation with ETT replacement), and T3 (92-100 h post-T2); these were analyzed using sonication and microbiological techniques to assess microbial colonization and antimicrobial resistance patterns. Results: In a total of 30 patients, bacteria from the ESKAPEE group (e.g., Klebsiella pneumoniae, Acinetobacter baumannii, Staphylococcus aureus) dominated the microbiota, increasing their prevalence over time. Resistance to carbapenems, colistin, and vancomycin was notably observed, particularly among K. pneumoniae and A. baumannii. Biofilm analysis revealed high persistence rates and the emergence of multidrug-resistant strains, underscoring the role of ETTs as reservoirs for resistant pathogens. The replacement of ETTs at T2 correlated with a shift in microbial composition and reduced biofilm-associated contamination. Conclusions: This study highlights the temporal evolution of antimicrobial resistance and biofilm-associated colonization in a limited number of ICU patients (30 patients). The findings support implementing routine ETT management strategies, including scheduled replacements and advanced biofilm-disruption techniques, to mitigate VAP risk and improve patient outcomes.}, }
@article {pmid40005812, year = {2025}, author = {Lira, RLS and Nogueira, FAB and Campos, RFPC and Ferreira, DRM and Roxo, PLBT and de Azevedo, CCS and Gimenes, ECM and Bastos, RLC and Nascimento, CEC and Nunes, FDO and Marques, MCP and Campos, CDL and Martinez, CG and Zagmignan, A and Silva, LCN and Ribeiro, RM and de Azevedo Dos Santos, APS and Carvalho, RC and de Sousa, EM}, title = {Mycobacterium abscessus subsp. massiliense: Biofilm Formation, Host Immune Response, and Therapeutic Strategies.}, journal = {Microorganisms}, volume = {13}, number = {2}, pages = {}, doi = {10.3390/microorganisms13020447}, pmid = {40005812}, issn = {2076-2607}, support = {FAPEMA: ACT-02510/23//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa e ao Desenvolvimento Cient&#xed;fico e Tecnol&#xf3;gico do Maranh&#xe3;o/ ; Universal-06536/22//Ceuma University/ ; }, abstract = {Infection by Mycobacterium abscessus subsp. massiliense poses a growing public health threat, especially to immunocompromised individuals. The pathogenicity of this mycobacterium is directly linked to its ability to form biofilms, complex structures that confer resistance to antibiotics and the host immune response. The extracellular matrix of the biofilm acts as a physical barrier, hindering the penetration of drugs and the action of the immune system, while also inducing a slow-growth state that reduces susceptibility to antibiotics. Current therapies, which involve prolonged use of multiple antibiotics, are often ineffective and cause significant side effects. Therefore, it is essential to explore new strategies targeting bacterial resistance and biofilm destruction. This narrative review explores the biofilm-forming capacity of Mycobacterium abscessus subsp. massiliense and the potential of novel therapeutic strategies. Promising approaches include inhibiting biofilm formation, developing drugs with improved penetration of the extracellular matrix, combination therapies with agents that destabilize the biofilm structure, and modulating the host immune response. Investing in research and development of new therapeutic strategies is essential to combat this resistant bacterium and improve patient outcomes.}, }
@article {pmid40005730, year = {2025}, author = {Leroy, G and Parizadeh, L and Cuny, H and Offret, C and Protat, M and Bazire, A and Rodrigues, S and Le Chevalier, P and Brillet, B and Gonzalez-Araya, R and Jégou, C and Fleury, Y}, title = {Pseudoalteromonas Strains as Biofilm Control Agents in Ostrea edulis Aquaculture: Reducing Biofilm Biovolume While Preserving Microbial Diversity.}, journal = {Microorganisms}, volume = {13}, number = {2}, pages = {}, doi = {10.3390/microorganisms13020363}, pmid = {40005730}, issn = {2076-2607}, abstract = {Biofilms in aquaculture tanks pose significant challenges, hindering cleaning processes and contributing to antibiotic resistance. This study investigated the effects of four Pseudoalteromonas strains on flat oyster (Ostrea edulis) rearing, with a specific focus on biofilm control and microbial communities. After confirming the safety of these strains for O. edulis, we monitored biofilm development and bacterial communities during a 4-month sexual maturation period. Biofilm biovolume was quantified using confocal laser scanning microscopy (CLSM), and bacterial community composition was analyzed via 16S rRNA gene metabarcoding of both biofilm and seawater samples. Our results revealed differences in bacterial community structure between biofilms and seawater. Furthermore, the presence of specific Pseudoalteromonas strains significantly impacted the composition of bacterial communities within the tanks. β-diversity analyses demonstrated that each strain exerted a unique influence on the bacterial community structure. Some Pseudoalteromonas strains effectively reduced biofilm biovolume without negatively impacting bacterial richness or diversity. These observations suggest that certain Pseudoalteromonas strains can effectively control biofilm formation while maintaining a diverse and potentially beneficial microbial community in O. edulis rearing tanks. The use of these strains as additives in aquaculture systems could offer several advantages, including reduced cleaning time and costs and a potential decrease in biocide usage.}, }
@article {pmid40005603, year = {2025}, author = {Zhang, T and Pei, Z and Wang, H and Zhao, J and Chen, W and Lu, W}, title = {Combined Analysis of Transcriptomes and Metabolomes Reveals Key Genes and Substances That Affect the Formation of a Multi-Species Biofilm by Nine Gut Bacteria.}, journal = {Microorganisms}, volume = {13}, number = {2}, pages = {}, doi = {10.3390/microorganisms13020234}, pmid = {40005603}, issn = {2076-2607}, support = {No. 32172216//National Natural Science Foundation of China/ ; No. 2022YFF1100203//National Key Research and Development Program of China/ ; }, abstract = {Biofilms are one of the ways microorganisms exist in natural environments. In recent years, research has gradually shifted its focus to exploring the complexity and interactions of multi-species biofilms. A study showed that nine gut bacteria can form a multi-species biofilm on wheat fibers (M9 biofilm). However, the previous study did not clarify the reasons why M9 exhibited a better biofilm formation ability than the mono-species biofilms. In this study, the gene expression levels and metabolic accumulation of the M9 multi-species biofilm and biofilms of each individual bacterium were analyzed using transcriptomes and metabolomes. The differentially expressed genes (DEGs) showed that there were 740 common DEGs that existed in all of the nine groups, and they could regulate five pathways related to bacterial motility, cellular communication, and signal transduction. The metabolome results revealed that many peptides/amino acids and derivatives were produced in the M9 biofilm. Furthermore, purine metabolism was significantly enhanced in the M9 biofilm. L-arginine, l-serine, guanosine, and hypoxanthine were the common differentially accumulated metabolites (DAMs). The combined analysis of the transcriptomes and metabolomes showed that there were 26 common DEGs highly correlated with the four common DAMs, and they were involved in five metabolic pathways related to amino acids and purines. These results indicate that M9 can regulate multi-species biofilm formation by modulating genes related to bacterial motility, cellular communication, signal transduction, and the metabolism of amino acids and purines. This study provides insights into the interactions of microbial biofilms.}, }
@article {pmid40002146, year = {2025}, author = {Fan, Q and Ning, M and Zeng, X and He, X and Bai, Z and Gu, S and Yuan, Y and Yue, T}, title = {Anti-Vibrio parahaemolyticus Mechanism of Hexanal and Its Inhibitory Effect on Biofilm Formation.}, journal = {Foods (Basel, Switzerland)}, volume = {14}, number = {4}, pages = {}, doi = {10.3390/foods14040703}, pmid = {40002146}, issn = {2304-8158}, support = {1348009//Doctor Scientific Research Start-up Fund of Henan University of Science and Technology/ ; 25A550011//Key Research Project Plan for Higher Education Institutions in Henan Province/ ; }, abstract = {Vibrio parahaemolyticus (V. parahaemolyticus) is one of the most prevalent foodborne pathogens worldwide. Hexanal is a natural aldehyde derived from plants. In this study, the antimicrobial and antibiofilm activities of hexanal against V. parahaemolyticus were investigated. Hexanal inhibited V. parahaemolyticus growth with a minimum inhibitory concentration (MIC) of 0.4 mg/mL. Hexanal (2 MIC and 4 MIC) increased the leakage of protein and lactic dehydrogenase, reduced intracellular ATP concentration, damaged membrane integrity, and induced abnormal V. parahaemolyticus morphology and ultrastructure. The results of colony enumeration suggested that hexanal exhibited bactericidal action against V. parahaemolyticus in different culture mediums and food systems (Spanish mackerel meat and shrimp paste). At 1/8 MIC and 1/4 MIC, hexanal inhibited biofilm formation of V. parahaemolyticus, as evidenced by crystal violet staining assay and scanning electron microscope (SEM) observation. Moreover, hexanal reduced the levels of extracellular polysaccharide, extracellular protein, and cyclic di-guanosine monophosphate (c-di-GMP) in V. parahaemolyticus. The result of real-time quantitative polymerase chain reaction (RT-qPCR) indicated that hexanal downregulated the expression of genes critical to V. parahaemolyticus biofilm development. This study provides a promising alternative for V. parahaemolyticus control and is conducive to promoting the application of hexanal in the food field.}, }
@article {pmid40001933, year = {2025}, author = {Almatroudi, A}, title = {Biofilm Resilience: Molecular Mechanisms Driving Antibiotic Resistance in Clinical Contexts.}, journal = {Biology}, volume = {14}, number = {2}, pages = {}, doi = {10.3390/biology14020165}, pmid = {40001933}, issn = {2079-7737}, support = {(QU-APC-2025)//Qassim University/ ; }, abstract = {Healthcare-associated infections pose a significant global health challenge, negatively impacting patient outcomes and burdening healthcare systems. A major contributing factor to healthcare-associated infections is the formation of biofilms, structured microbial communities encased in a self-produced extracellular polymeric substance matrix. Biofilms are critical in disease etiology and antibiotic resistance, complicating treatment and infection control efforts. Their inherent resistance mechanisms enable them to withstand antibiotic therapies, leading to recurrent infections and increased morbidity. This review explores the development of biofilms and their dual roles in health and disease. It highlights the structural and protective functions of the EPS matrix, which shields microbial populations from immune responses and antimicrobial agents. Key molecular mechanisms of biofilm resistance, including restricted antibiotic penetration, persister cell dormancy, and genetic adaptations, are identified as significant barriers to effective management. Biofilms are implicated in various clinical contexts, including chronic wounds, medical device-associated infections, oral health complications, and surgical site infections. Their prevalence in hospital environments exacerbates infection control challenges and underscores the urgent need for innovative preventive and therapeutic strategies. This review evaluates cutting-edge approaches such as DNase-mediated biofilm disruption, RNAIII-inhibiting peptides, DNABII proteins, bacteriophage therapies, antimicrobial peptides, nanoparticle-based solutions, antimicrobial coatings, and antimicrobial lock therapies. It also examines critical challenges associated with biofilm-related healthcare-associated infections, including diagnostic difficulties, disinfectant resistance, and economic implications. This review emphasizes the need for a multidisciplinary approach and underscores the importance of understanding biofilm dynamics, their role in disease pathogenesis, and the advancements in therapeutic strategies to combat biofilm-associated infections effectively in clinical settings. These insights aim to enhance treatment outcomes and reduce the burden of biofilm-related diseases.}, }
@article {pmid40001569, year = {2025}, author = {Fareid, MA and El-Sherbiny, GM and Askar, AA and Abdelaziz, AM and Hegazy, AM and Ab Aziz, R and Hamada, FA}, title = {Impeding Biofilm-Forming Mediated Methicillin-Resistant Staphylococcus aureus and Virulence Genes Using a Biosynthesized Silver Nanoparticles-Antibiotic Combination.}, journal = {Biomolecules}, volume = {15}, number = {2}, pages = {}, doi = {10.3390/biom15020266}, pmid = {40001569}, issn = {2218-273X}, support = {RG-24 070.//Scientific Research Deanship at University of Ha'il - Saudi Arabia/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Methicillin-Resistant Staphylococcus aureus/drug effects/genetics ; *Silver/pharmacology/chemistry ; *Metal Nanoparticles/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; Humans ; *Microbial Sensitivity Tests ; Oxacillin/pharmacology ; Streptomyces/genetics/metabolism ; Virulence/drug effects/genetics ; }, abstract = {Methicillin-resistant Staphylococcus aureus (MRSA) continues to represent a significant clinical challenge, characterized by consistently elevated rates of morbidity and mortality. Care regimen success is still difficult and necessitates assessing new antibiotics as well as supplemental services, including source control and searching for alternative approaches to combating it. Hence, we propose to synthesize silver nanoparticles (Ag-NPs) by employing a cell-free filter (CFF) of Streptomyces sp. to augment antibiotic activity and combat biofilm-forming MRSA. Seven bacterial isolates from clinical samples were identified, antibiotics were profiled with Vitek-2, and the phenotypic detecting of biofilm with Congo red medium and microplate assay was carried out. The PCR technique was used for detecting genes (icaA and icaD) coded in biofilm forming. The characterization of Ag-NPs was performed using several analytical methods, such as UV spectroscopy, dynamic light scattering (DLS), zeta potential measurement, transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The antibacterial properties of Ag-NPs and oxacillin-Ag-NPs were assessed against standard strains and clinical isolates by employing the agar well diffusion technique and the microdilution assay. The biogenic synthesis Ag-NPs resulted in uniformly spherical particles, with an average size of 20 nm. These Ag-NPs demonstrated significant activity against biofilm-forming MRSA, with minimum inhibitory concentrations (MICs) ranging from 12 to 15 μg/mL. Additionally, Ag-NPs completely impede biofilm formation by MRSA at sublethal doses of 0.75 MICs. The expression levels of the icaA and icaD genes were reduced by 1.9- to 2.2- and 2.4- to 2.8-fold, respectively. A significant synergistic effect was noted when Ag-NPs were used in combination with oxacillin, leading to reduced MICs of 1.87 μg/mL for oxacillin and 4.0 μg/mL for Ag-NPs against MRSA. The FICi of 0.375 further validated the synergistic relationship between oxacillin and Ag-NPs at the concentrations of 1.87 and 4 μg/mL. Findings from the time-kill test demonstrated the highest reduction in log10 (CFU)/mL of the initial MRSA inoculum after 12-hour exposure. The cytotoxicity analysis of Ag-NPs revealed no significant cytotoxic effects on the human skin cell line HFB-4 at low concentrations, with IC50 values of 61.40 µg/mL for HFB-4 and 34.2 µg/mL for HepG-2. Comparable with oxacillin-Ag-NPs, Ag-NPs showed no cytotoxic effects on HFB-4 at different concentrations and exhibited an IC50 value of 31.2 against HepG-2-cells. In conclusion, the biosynthesis of Ag-NPs has demonstrated effective antibacterial activity against MRSA and has completely hindered biofilm formation, suggesting a valuable alternative for clinical applications.}, }
@article {pmid40001426, year = {2025}, author = {Andrade, M and Neves, J and Bento, M and Marques, J and Seabra, SG and Silveira, H and Rodrigues, L and Armada, A and Viveiros, M and Couto, I and Costa, SS}, title = {Evaluation of Amlodipine and Imipramine Efficacy to Treat Galleria mellonella Infection by Biofilm-Producing and Antimicrobial-Resistant Staphylococcus aureus.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {14}, number = {2}, pages = {}, doi = {10.3390/antibiotics14020183}, pmid = {40001426}, issn = {2079-6382}, support = {LA/P/0117/2020//Funda&#xe7;&#xe3;o para a Ci&#xea;ncia e Tecnologia/ ; UIDB/04413/2020//Funda&#xe7;&#xe3;o para a Ci&#xea;ncia e Tecnologia/ ; 2022.07931.PTDC//Funda&#xe7;&#xe3;o para a Ci&#xea;ncia e Tecnologia/ ; UI/BD/154472/2022//Funda&#xe7;&#xe3;o para a Ci&#xea;ncia e Tecnologia/ ; CEECIND/00450/2017/CP1415/CT0001//Funda&#xe7;&#xe3;o para a Ci&#xea;ncia e Tecnologia/ ; CEECINST/00102/2018/CP1567/CT0040//Funda&#xe7;&#xe3;o para a Ci&#xea;ncia e Tecnologia/ ; CEECINST/00042/2021/CP1773/CT0009//Funda&#xe7;&#xe3;o para a Ci&#xea;ncia e Tecnologia/ ; }, abstract = {Background/Objectives: Antimicrobial-resistant Staphylococcus aureus is a growing threat to human health for which alternative therapeutic options are needed. In this study, we aimed to evaluate the efficacy of amlodipine (AML) and imipramine (IMI) to treat S. aureus infection in the Galleria mellonella larval model by targeting efflux and biofilms, which are relevant contributors to antimicrobial resistance and virulence in S. aureus. Methods: In-house reared G. mellonella were used in virulence assays to determine the infective dose of two S. aureus strains differing in the expression of norA (gene encoding the native NorA efflux pump). Toxicology assays were conducted to determine the drugs' LD50 for G. mellonella. Drug efficacy assays were performed to evaluate the potential of amlodipine, imipramine and the control drugs ciprofloxacin (CIP) and enalapril (ENA) to clear S. aureus infection in G. mellonella. Results: Survival analysis defined the infective dose as 1 × 10[7] CFU/larva for both strains. High LD50 values were determined (CIP: >1000 mg/kg; AML: >640 mg/kg; IMI: 1141 mg/kg; ENA: >1280 mg/kg), revealing a high tolerance of G. mellonella to these drugs. AML at 15 mg/kg and IMI at 100 mg/kg increased the larvae survival by 20% (p = 0.04) and 11% (p = 0.11), respectively, also positively affecting health score indexes. In agreement with the literature, ciprofloxacin at >100 mg/kg promoted larvae survival by >73%. Conclusions: Amlodipine and imipramine show mild potential as new therapeutic options for managing S. aureus infections but are promising as new lead molecules. This study also reinforces G. mellonella as a sustainable, reliable model for drug evaluation.}, }
@article {pmid40001424, year = {2025}, author = {Barak, TH and Eryilmaz, M and Karaca, B and Servi, H and Kara Ertekin, S and Dinc, M and Ustuner, H}, title = {Antimicrobial, Anti-Biofilm, Anti-Quorum Sensing and Cytotoxic Activities of Thymbra spicata L. subsp. spicata Essential Oils.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {14}, number = {2}, pages = {}, doi = {10.3390/antibiotics14020181}, pmid = {40001424}, issn = {2079-6382}, abstract = {Background/Objectives: Essential oils of Thymbra spicata subsp. spicata are known for their rich phytochemical content and bioactive properties. This study aimed to evaluate the antimicrobial, anti-biofilm and anti-quorum sensing, as well as the cytotoxic activities of T. spicata subsp. spicata essential oils (TS-EO1 and TS-EO2) obtained from two different localities in Türkiye, along with a detailed chemical composition analysis. Methods: TS-EO1 and TS-EO2 were obtained by the hydrodistillation method and analyzed using Gas Chromatography-Mass Spectrometry (GC-MS) to determine their phytochemical profiles. Antimicrobial activities were assessed against Gram-positive and Gram-negative bacteria, and fungal strains were assessed using the broth microdilution method. Anti-biofilm and anti-quorum sensing activities were evaluated using Pseudomonas aeruginosa PAO1 and Chromobacterium violaceum ATCC 12472, respectively. Cytotoxic properties were tested on four cell lines (A549, MCF-7, U87MG, and L929) using the MTT assay. Results: Both essential oil samples were rich in carvacrol (54.3% and 54.1%), followed by p-cymene and γ-terpinene. The essential oils exhibited significant antimicrobial activity, particularly against Staphylococcus aureus (6.25 mg/mL) and Candida parapsilosis (0.20 mg/mL). Sub-MIC concentrations significantly inhibited biofilm formation and quorum sensing. Both samples showed moderate cytotoxic properties against human cancer cell lines, particularly A549 (IC50: 116.3 and 134.4 μg/mL, respectively). Conclusions: This study showed that T. spicata subsp. spicata essential oils have significant antimicrobial, anti-biofilm, and anti-quorum sensing properties against various bacteria and fungi, along with moderate cytotoxic effects, indicating their medicinal and pharmaceutical potentials. This is the first study which revealed anti-biofilm and anti-quorum sensing properties of T. spicata essential oils to our knowledge.}, }
@article {pmid40001401, year = {2025}, author = {Wintachai, P and Santini, JM and Thonguppatham, R and Stroyakovski, M and Surachat, K and Atipairin, A}, title = {Isolation, Characterization, and Anti-Biofilm Activity of a Novel Kaypoctavirus Against K24 Capsular Type, Multidrug-Resistant Klebsiella pneumoniae Clinical Isolates.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {14}, number = {2}, pages = {}, doi = {10.3390/antibiotics14020157}, pmid = {40001401}, issn = {2079-6382}, support = {Grant No. RSPG-WU-09/2567 and Contract Number WU-CIA-00902/2024//The Plant Genetic Conservation Project under The Royal initiative of Her Royal Highness Princess Maha Chakri Sirindhorn (RSPG-WU-09/2567) and The International Research Collaboration Scheme (WU-CIA-00902/2024), Walailak University/ ; }, abstract = {Background/Objectives: The significant outbreak of multidrug-resistant Klebsiella pneumoniae has emerged as a primary global concern associated with high morbidity and mortality rates. Certain strains of K. pneumoniae are highly resistant to most antibiotics available in clinical practice, exacerbating the challenge of bacterial infections. Methods: Phage vB_KpnP_PW7 (vKPPW7) was isolated and characterized. Its morphology, stability, adsorption rate, one-step growth curve, lytic activity, whole-genome sequence analysis, and antibacterial and antibiofilm activities were evaluated. Results: The virulent phage has a 73,658 bp linear dsDNA genome and was classified as a new species of the genus Kaypoctavirus, subfamily Enquatrovirinae, and family Schitoviridae. Phage vKPPW7 has a high adsorption rate, a short latent period, and a large burst size. The phage showed activity against 18 K. pneumoniae isolates with the K24 capsular type but was unable to lyse K. pneumoniae isolates whose capsular type was not classified as K24. Additionally, phage vKPPW7 demonstrated strong stability across various temperatures and pH values. The phage exhibited antibacterial activity, and scanning electron microscopy (SEM) confirmed its ability to lyse MDR K. pneumoniae with the K24 capsular type. Furthermore, phage vKPPW7 effectively removed preformed biofilm and prevented biofilm formation, resulting in reduced biofilm biomass and biofilm viability compared to controls. The architecture of phage-treated biofilms was confirmed under SEM. Conclusions: These findings suggest that phage vKPPW7 holds promise for development as a therapeutic or biocontrol agent.}, }
@article {pmid40001359, year = {2025}, author = {Tabassum, N and Khan, F and Jeong, GJ and Oh, DK and Kim, YM}, title = {Controlling Oral Polymicrobial Biofilm Using Usnic Acid on the Surface of Titanium in the Artificial Saliva Media.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {14}, number = {2}, pages = {}, doi = {10.3390/antibiotics14020115}, pmid = {40001359}, issn = {2079-6382}, support = {2022R1A2B5B01001998 and RS-2023-00241461//Basic Science Research Program through the National Research Foundation (NRF) of Korea grant funded by the Ministry of Education/ ; 202416570001//Research Grant of Pukyong National University/ ; }, abstract = {Background/Objectives: Titanium dental implants, while highly successful, face challenges due to polymicrobial infections leading to peri-implantitis and implant failure. Biofilm formation on implant surfaces is the primary cause of these infections, with factors such as matrix production and cross-kingdom interactions contributing to the microbial accumulation of bacterial and fungal pathogens species. To combat this issue, naturally derived molecules have been reported to overcome the hurdle of antimicrobial resistance against the application of conventional antibiotics and antifungals. Methods: The present study aimed to employ the lichen-derived molecules, usnic acid (UA), to retard the development of biofilms of bacterial and fungal pathogens on the surface of titanium kept in the human artificial saliva (HAS) working as a growth-supporting, host-mimicking media. Results: The minimum inhibitory concentration of UA in HAS towards Candida albicans was >512 µg/mL, whereas against Staphylococcus aureus and Streptococcus mutans, it was determined to be 512 µg/mL. Whereas, in the standard growth media, the MIC value of UA towards S. mutans and S. aureus were 8 and 16 µg/mL; however, against C. albicans, it was 512 µg/mL. UA synergistically enhanced the efficacy of the antibiotics toward bacterial pathogens and the efficacy of antifungals against C. albicans. The antibiofilm results depict the fact that in the HAS, UA significantly reduced both mono-species of S. mutans, S. aureus, and C. albicans and mixed-species biofilm of C. albicans with S. mutans and S. aureus on the surface of the titanium. Conclusions: The present study showed that UA is a promising natural drug that can control oral polymicrobial disease as a result of the application of dental implants.}, }
@article {pmid39998686, year = {2025}, author = {Scala, V and Salustri, M and Merfa, MV and Beccaccioli, M and Lascala, L and De La Fuente, L and Reverberi, M}, title = {XadA-like adhesin XADA2 regulates biofilm formation in X. fastidiosa subsp. fastidiosa putatively by engaging oleic-acid derived oxylipins.}, journal = {Molecular biology reports}, volume = {52}, number = {1}, pages = {263}, pmid = {39998686}, issn = {1573-4978}, mesh = {*Biofilms/growth &amp; development ; *Adhesins, Bacterial/metabolism/genetics ; *Xylella/genetics/physiology/metabolism/pathogenicity ; *Oleic Acid/metabolism ; *Oxylipins/metabolism ; Bacterial Adhesion ; Bacterial Proteins/metabolism/genetics ; Nicotiana/microbiology ; }, abstract = {BACKGROUND: The oxylipins 10-HpOME and 7,10-DiHoME derive from oleic acid and have been extensively studied for their ability to regulate contractions, microcolony formation and biofilm formation in the model organism Pseudomonas aeruginosa.<br><br>METHODS AND RESULTS: Xylella fastidiosa subsp. pauca strain de Donno has been reported to produce 10-HpOME and 7,10-DiHOME in vivo when inoculated in the model plant Nicotiana tabacum or in naturally occurring infected olive trees. In this study, we deciphered the relationship among cell adhesion and oxylipins in Xylella fastidiosa subsp. fastidiosa (Temecula1 strain) and subsp. multiplex (AlmaEM3 strain). The role of the PD0744 gene, encoding for XadA2, a non-fimbrial adhesin belonging to the trimeric autotransporter family, probably involved in the surface attachment required in the initial phase of biofilm formation was investigated. PD0744 deletion mutants in two X. fastidiosa strains were generated, through homologous recombination, and the impact of its deletion on bacterial lifestyle was assessed. In vitro assays were performed to characterize the mutant phenotype, particularly in twitching motility and its capability to grow and form biofilm. Mutants showed a reduced twitching motility and biofilm formation compared to wild type strains. HPLC-MS/MS analysis revealed a decrease in 7,10-DiHOME production together with an increase of its precursor 10-HpOME in the mutants.<br><br>CONCLUSIONS: 7,10-DiHOME could be a crucial signaling molecule to promote biofilm formation and twitching motility, whose synthesis likely depends on a signal transduction requiring the presence of the adhesin XadA2 and thus not working if this protein is depleted. These results help understanding the complex regulation of biofilm formation in this devastating pathogen.}, }
@article {pmid39998317, year = {2025}, author = {Wang, J and Yu, G and Fang, Q and Xu, Y and Zhang, J and Hui, A and Xuan, S and Leung, KC}, title = {Hollow-Structured Nanorobot with Excellent Magnetic Propulsion for Catalytic Pollutant Degradation, Anti-Bacterial and Biofilm Removal.}, journal = {Advanced healthcare materials}, volume = {}, number = {}, pages = {e2404208}, doi = {10.1002/adhm.202404208}, pmid = {39998317}, issn = {2192-2659}, support = {12072338//National Natural Science Foundation of China/ ; S202305a12020030//Key Project of Anhui Province Science and Technology Innovation Platform/ ; Hwk2022zc044//Applied Medical Research Project of Hefei Health Commission/ ; RMGS-2022-13-07//Hong Kong Baptist University/ ; }, abstract = {Chemical pollution, pathogenic bacteria, and bacterial biofilms pose significant threats to public health. Although various nanoplatforms with both catalytic and antibacterial activities have been developed, creating a remotely controllable nanorobot with precise targeting and propulsion capabilities remains a challenge. This study presents the fabrication of a hollow-structured Fe3O4@AgAu@polydopamine (PDA) nanosphere, which demonstrated controllable catalytic activity and superior magnetically enhanced antibacterial and biofilm removal properties. The AgAu bimetallic nanorods are assembled between the Fe3O4 core and the biocompatible PDA, resulting in a magnetic nanorobot with high photothermal conversion efficiency (54%) and excellent catalytic activity. Importantly, due to the efficient propulsion behavior originating from the magnetic Fe3O4, organic pollutants such as 4-nitrophenol and methylene blue can be accurately degraded by the catalytic Fe3O4@AgAu@PDA magnetic nanorobots in a simulated wastewater pool. By incorporating the zinc phthalocyanine (ZnPc) photosensitizer, the Fe3O4@AgAu@PDA-ZnPc nanosphere exhibits a synergistic "photothermal-photodynamic-Ag[+]" antibacterial effect against Escherichia coli and Staphylococcus aureus. Remarkably, the antibacterial rate can be enhanced to 99.99% by applying magnetic propulsion via a rotating magnetic field (RMF). Furthermore, this unique magnetic propulsion endows the nanorobot with effective biofilm removal capabilities in both flat surfaces and tubular structures, highlighting its advantages over traditional antibacterial agents in dynamic removal applications.}, }
@article {pmid39998256, year = {2025}, author = {Williams, I and Tuckerman, JS and Peters, DI and Bangs, M and Williams, E and Shin, IJ and Kaspar, JR}, title = {A strain of Streptococcus mitis inhibits biofilm formation of caries pathogens via abundant hydrogen peroxide production.}, journal = {Applied and environmental microbiology}, volume = {}, number = {}, pages = {e0219224}, doi = {10.1128/aem.02192-24}, pmid = {39998256}, issn = {1098-5336}, abstract = {Commensal oral streptococci that colonize supragingival biofilms deploy mechanisms to combat competitors within their niche. Here, we determined that Streptococcus mitis more effectively inhibited biofilm formation of Streptococcus mutans compared to other oral streptococci. This phenotype was common among all isolates of S. mutans, but was specific to a single strain of S. mitis, ATCC 49456. We documented ATCC 49456 to accumulate four to five times more hydrogen peroxide (H2O2) than other Streptococcus species tested, and 5-18 times more than other S. mitis strains assayed. S. mutans biofilm formation inhibition was dependent on cell contact/proximity and reduced when grown in media containing catalase or with a S. mitis mutant of pyruvate oxidase (spxB; pox), confirming that SpxB-dependent H2O2 production was a major antagonistic factor. Addition of S. mitis within hours after S. mutans inoculation was effective at reducing biofilm biomass, but not for 24 h pre-formed biofilms in an SpxB-dependent manner. Transcriptome analysis revealed responses for both S. mitis and S. mutans, with several S. mutans differentially expressed genes following a gene expression pattern we have previously described, while others being unique to the interaction with S. mitis. Finally, we show that S. mitis also affected coculture biofilm formation of several other commensal streptococci as well as cariogenic Streptococcus sobrinus. Our study shows that strains with abundant H2O2 production are effective at inhibiting initial growth of caries pathogens like S. mutans, but are less effective at disrupting pre-formed biofilms and have the potential to influence the stability of other oral commensal strains.IMPORTANCEAntagonistic properties displayed by oral bacteria have been sought as therapeutic approaches against dental caries pathogens like Streptococcus mutans. An emergent theme has been the ability of select strains that produce high amounts of hydrogen peroxide to effectively inhibit the growth of S. mutans within in vitro and in vivo models. Our study builds on these previous findings by determining that Streptococcus mitis ATCC 49456 is a high hydrogen peroxide producer, compared to other Streptococcus species as well as additional strains of S. mitis. In addition to S. mutans, we show that ATCC 49456 also affects biofilm formation of other oral streptococci, a non-desirable trait that should be weighed heavily for strains under consideration as probiotics. Further phenotypic characterization of strains like S. mitis ATCC 49456 in mixed-species settings will allow us to hone in on qualities that are optimal for probiotic strains that are intended to prevent the emergence of odontopathogens.}, }
@article {pmid39998206, year = {2025}, author = {Zarnowski, R and Horton, MV and Johnson, CJ and Vang, PC and Uram, J and Fernando, LDP and Vlach, J and Heiss, C and Azadi, P and Nett, JE and Andes, DR}, title = {Dual function of Candida auris mannosyltransferase, MTN5, in biofilm community protection from antifungal therapy and the host.}, journal = {mBio}, volume = {}, number = {}, pages = {e0034625}, doi = {10.1128/mbio.00346-25}, pmid = {39998206}, issn = {2150-7511}, abstract = {UNLABELLED: Screen of mutants from a mannosyltransferase family identified the importance of MNT5 for C. auris biofilm drug resistance and neutrophil evasion. Biochemical analysis of the mnt5∆ mutant matrix and cell wall identified alterations in the mannan structures. Resistance and matrix for mnt5∆ were restored with delivery of wild-type matrix via extracellular vesicles. Analysis of the mnt5∆ cell wall revealed a reduction in mannan and compensatory increase in cell surface glucan and chitin, suggesting a role for MNT5 in mannan masking of pathogen-associated molecular patterns.<br><br>IMPORTANCE: C. auris recalcitrance is linked to biofilm drug resistance and immune evasion. The mannosyltransferase encoded by MNT5 is necessary for both phenotypes and may serve as a useful therapeutic target.}, }
@article {pmid39997604, year = {2025}, author = {Costa, TL and Puppin-Rontani, RM and de Castilho, ARF}, title = {Preventing Oral Dual Biofilm Development with Innovative Bioactive Varnishes.}, journal = {Journal of functional biomaterials}, volume = {16}, number = {2}, pages = {}, doi = {10.3390/jfb16020070}, pmid = {39997604}, issn = {2079-4983}, support = {124247/2019-9//National Council for Scientific and Technological Development/ ; 443036/2014-4//National Council for Scientific and Technological Development/ ; 2014/01723-9//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado de S&#xe3;o Paulo/ ; Finance Code 001//Coordena&#xe7;&#xe3;o de Aperfeicoamento de Pessoal de N&#xed;vel Superior/ ; }, abstract = {This study introduces innovative varnishes incorporating natural bioactive compounds to inhibit the formation of oral dual biofilms, a critical contributor to dental caries and other oral diseases. The purpose of this study was to evaluate the effectiveness of bioactive varnishes containing tt-farnesol, quercetin, and theobromine in inhibiting the formation of mixed Streptococcus mutans and Candida albicans biofilms. Mixed biofilms of Streptococcus mutans UA159 and Candida albicans SC5314 were grown in 96-well plates containing a specialized culture medium. Approximately 0.2 mL of experimental varnishes with A-1.5% or B-4.5% concentrations of tt-farnesol, quercetin, and theobromine were separately added to the wells using a disposable applicator, with a vehicle varnish (lacking bioactives) serving as the control. Biofilms were incubated at 37 °C with 5% CO2 for 24 h. Microbial viability was determined in terms of colony-forming units per milliliter (CFU/mL), and biofilm morphology was evaluated qualitatively via scanning electron microscopy (SEM). Statistical analyses were performed using ANOVA/Tukey tests at a 5% significance level. Varnishes A and B achieved significant reductions in microbial populations within the biofilms (p < 0.05) compared to the vehicle control (C). SEM imaging revealed marked structural disruptions in the biofilms, validating the quantitative results. Higher bioactive concentrations demonstrated enhanced inhibitory effects. Bioactive varnishes enriched with theobromine, quercetin, and tt-farnesol represent a novel and effective strategy for inhibiting oral dual biofilm development, offering a promising advancement in preventive dentistry.}, }
@article {pmid39997574, year = {2025}, author = {Franović, B and Čandrlić, M and Blašković, M and Renko, I and Komar Milas, K and Markova-Car, EP and Mohar Vitezić, B and Gabrić, D and Gobin, I and Vranić, SM and Perić Kačarević, &#x17d; and Peloza, OC}, title = {The Microbial Diversity and Biofilm Characteristics of d-PTFE Membranes Used for Socket Preservation: A Randomized Controlled Clinical Trial.}, journal = {Journal of functional biomaterials}, volume = {16}, number = {2}, pages = {}, doi = {10.3390/jfb16020040}, pmid = {39997574}, issn = {2079-4983}, support = {IP-2020-02-7875//Croatian science fond/ ; UNIRI-iskusni-biomed-23-167//University of Rijeka/ ; }, abstract = {BACKGROUND: Understanding microbial colonization on different membranes is critical for guided bone regeneration procedures such as socket preservation, as biofilm formation may affect healing and clinical outcomes. This randomized controlled clinical trial (RCT) investigates, for the first time, the microbiome of two different high-density polytetrafluoroethylene (d-PTFE) membranes that are used in socket preservation on a highly molecular level and in vivo.<br><br>METHODS: This RCT enrolled 39 participants, with a total of 48 extraction sites, requiring subsequent implant placement. Sites were assigned to two groups, each receiving socket grafting with a composite bone graft (50% autogenous bone, 50% bovine xenograft) and covered by either a permamem[&#xae;] (group P) or a Cytoplast&#x2122; (group C). The membranes were removed after four weeks and analyzed using scanning electron microscopy (SEM) for bacterial adherence, qPCR for bacterial species quantification, and next-generation sequencing (NGS) for microbial diversity and composition assessment.<br><br>RESULTS: The four-week healing period was uneventful in both groups. The SEM analysis revealed multispecies biofilms on both membranes, with membranes from group C showing a denser extracellular matrix compared with membranes from group P. The qPCR analysis indicated a higher overall bacterial load on group C membranes. The NGS demonstrated significantly higher alpha diversity on group C membranes, while beta diversity indicated comparable microbiota compositions between the groups.<br><br>CONCLUSION: This study highlights the distinct microbial profiles of two d-PTFE membranes during the four-week socket preservation period. Therefore, the membrane type and design do, indeed, influence the biofilm composition and microbial diversity. These findings may have implications for healing outcomes and the risk of infection in the dental implant bed and should therefore be further explored.}, }
@article {pmid39996995, year = {2025}, author = {Netsch, A and Sen, S and Horn, H and Wagner, M}, title = {In Situ Biofilm Monitoring Using a Heat Transfer Sensor: The Impact of Flow Velocity in a Pipe and Planar System.}, journal = {Biosensors}, volume = {15}, number = {2}, pages = {}, doi = {10.3390/bios15020093}, pmid = {39996995}, issn = {2079-6374}, support = {02WER1531//Federal Ministry of Education and Research/ ; }, mesh = {*Biofilms ; *Biosensing Techniques ; Hot Temperature ; Hydrodynamics ; Models, Theoretical ; }, abstract = {Industrially applied bioelectrochemical systems require long-term stable operation, and hence the control of biofilm accumulation on the electrodes. An optimized application of biofilm control mechanisms presupposes on-line, in-situ monitoring of the accumulated biofilm. Heat transfer sensors have successfully been integrated into industrial systems for on-line, non-invasive monitoring of biofilms. In this study, a mathematical model for the description of the sensitivity of a heat transfer biofilm sensor was developed, incorporating the hydrodynamic conditions of the fluid and the geometrical properties of the substratum. This model was experimentally validated at different flow velocities by integrating biofilm sensors into cylindrical pipes and planar mesofluidic flow cells with a carbonaceous substratum. Dimensionless sensor readings were correlated with the mean biovolume measured gravimetrically, and optical coherence tomography was used to determine the sensors' sensitivity. The biofilm sensors applied in the planar flow cells revealed an increase in sensitivity by a factor of 6 compared to standard stainless steel pipes, as well as improved sensitivity at higher flow velocities.}, }
@article {pmid39996440, year = {2025}, author = {Pan, G and Zheng, J and Li, Z and Duan, Q and Zhang, M and Wang, D}, title = {Dual-responsive polydopamine-embellished Zn-MOFs enabling synergistic photothermal and antibacterial metal ion therapy for oral biofilm eradication.}, journal = {Journal of materials chemistry. B}, volume = {}, number = {}, pages = {}, doi = {10.1039/d4tb02427c}, pmid = {39996440}, issn = {2050-7518}, abstract = {Oral biofilms are associated with various oral diseases causing pain and discomfort, and pose a severe threat to general health. Conventional surgical debridement and antibacterial therapy often yield unsatisfactory outcomes because they either fail to fully and painlessly eliminate biofilms or increase the risk of bacterial resistance. In this study, we synthesized polydopamine-embellished Zn-MOFs (ZIF-8@PDA NPs), which can degrade under mildly acidic conditions to release Zn[2+]. These nanoparticles also convert near-infrared light energy into heat, thereby enabling synergistic photothermal and antibacterial metal ion therapy for oral biofilm eradication. Our findings reveal that therapy with ZIF-8@PDA NPs, when exposed to near-infrared radiation, demonstrates exceptional antibacterial efficacy and is highly effective in eradicating oral biofilms both in vitro and ex vivo. Furthermore, we used an in vivo rodent tooth biofilm model to demonstrate the suppression of dental caries. This work presents a promising solution for preventing and suppressing dental caries as well as other treating diseases linked to oral biofilm infections.}, }
@article {pmid39996424, year = {2025}, author = {Ma, W and Luo, J and Liu, H and Du, Q and Hao, T and Jiang, Y and Huang, Z and Lan, L and Li, Z and Li, T}, title = {Chemoenzymatic Synthesis of Highly O-Glycosylated MUC7 Glycopeptides for Probing Inhibitory Activity against Pseudomonas aeruginosa Biofilm Formation.}, journal = {Angewandte Chemie (International ed. in English)}, volume = {}, number = {}, pages = {e202424312}, doi = {10.1002/anie.202424312}, pmid = {39996424}, issn = {1521-3773}, abstract = {MUC7, a highly glycosylated protein in saliva and respiratory tract, plays potential roles in facilitating bacterial clearance and preventing microbial invasion. The complexity of glycan structures and multiplicity of glycosylation sites of MUC7 make it very difficult to explore accurate biofunctions against pathogens. Here, we report an efficiently convergent chemoenzymatic approach to firstly synthesize highly O-glycosylated MUC7 glycopeptides with nine glycosylation sites bearing various glycoforms via the combined use of hydrophobic tag-assisted liquid-phase peptide synthesis and enymatic-catalyzed glycan elongation. Biological evaluations reveal that different glycoforms of synthetic MUC7 glycopeptides mediate unique activities against biofilm formation of Pseudomonas aeruginosa, among which sialylated MUC7 glycopeptide exhibits better inhibitory activity and has the potential to develop antibacterial drugs.}, }
@article {pmid39996001, year = {2025}, author = {Datta, A and Saha, R and Sahoo, S and Roy, AR and Basu, S and Mahajan, G and Panja, SC and Mukherjee, J}, title = {Production of an Innovative, Surface Area-Enhanced and Biodegradable Biofilm-Generating Device by 3D Printing.}, journal = {Engineering in life sciences}, volume = {25}, number = {2}, pages = {e202400046}, pmid = {39996001}, issn = {1618-0240}, abstract = {The enhanced surface cylindrical flask (ESCF) consists of an eight-striped inner arrangement holding 16 standard microscopic slides placed inside a cylindrical vessel. The specially designed spatula-accessible slides can be withdrawn from the vessel during cultivation without disturbing biofilm formation through an innovative window-flap accessibility mechanism. The vessel and its accessories were three-dimensional (3D) printed by applying a fused deposition modeling technique utilizing biodegradable polylactic acid. Biofilms of clinically relevant bacteria namely Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli were successfully grown in the ESCF and observed through confocal laser scanning microscopy. Advantages of the device include an enhanced surface area for biofilm formation, ease of insertion and removal of microscopic slides, convenient fitting into standard rotary shaker platforms, creation of anoxic/microaerophilic environment inside the vessel as well as the feasibility of pH, dissolved gases, and metabolite measurements in the liquid surrounding the biofilm. The ESCF will find widespread application in medical, industrial, and environmental disciplines.}, }
@article {pmid39994590, year = {2025}, author = {Mahshouri, P and Alikhani, MY and Momtaz, HE and Doosti-Irani, A and Shokoohizadeh, L}, title = {Analysis of phylogroups, biofilm formation, virulence factors, antibiotic resistance and molecular typing of uropathogenic Escherichia coli strains isolated from patients with recurrent and non-recurrent urinary tract infections.}, journal = {BMC infectious diseases}, volume = {25}, number = {1}, pages = {267}, pmid = {39994590}, issn = {1471-2334}, abstract = {BACKGROUND: Uropathogenic Escherichia coli (UPEC) is the predominant cause of urinary tract infections (UTIs), and the recurrence of these infections poses significant treatment challenges.<br><br>OBJECTIVE: This study aimed to compare the phylogroups, biofilm formation, virulence factors, and antibiotic resistance of UPEC strains in patients with recurrent versus non-recurrent UTIs in Hamadan City, Western Iran.<br><br>MATERIALS AND METHODS: A total of 110 E. coli isolates were collected from urine cultures across three major hospitals and laboratories. The isolates were confirmed through biochemical tests, and their antibiotic resistance profiles were evaluated using the disk diffusion method. Biofilm production was assessed using the microtiter plate method, while virulence genes and phylogroup determination were analyzed via PCR. Real-time PCR was employed to compare the expression levels of the pap and fimH virulence genes.<br><br>RESULTS: The results indicated that 73% of isolates were from non-recurrent UTI patients, with a higher incidence in females and children under 10 years. A significant difference was detected in the underlying diseases and the expression of the pap between the recurrent and non-recurrent groups. Antibiotic resistance was notably significant, particularly against Ampicillin-sulbactam, Trimethoprim-Sulfamethoxazole, Nalidixic acid, and Ciprofloxacin, with 77% of strains classified as multi-drug resistant (MDR). Despite differences in the rates of ESBL production between recurrent (53%) and non-recurrent (42.5%) strains, no significant differences were observed in antibiotic resistance, biofilm formation, virulence factors, or phylogroups between the two groups. Phylogenetic analysis revealed a predominance of phylogroups B2 and D, with high genetic diversity among the isolates.<br><br>CONCLUSION: The study highlights the traits of UPEC strains in recurrent and non-recurrent UTIs, showing high antibiotic resistance and genetic diversity among isolates. The study found notable differences in underlying diseases and the expression of the pap gene between recurrent and non-recurrent groups, suggesting that these factors may play a crucial role in the recurrence of infections. Further investigation into these differences could enhance our understanding and management of recurrent UTIs.}, }
@article {pmid39994536, year = {2025}, author = {Wu, CY and Huang, HT and Chiang, YT and Lee, KT}, title = {Surfactin inhibits enterococcal biofilm formation via interference with pilus and exopolysaccharide biosynthesis.}, journal = {BMC microbiology}, volume = {25}, number = {1}, pages = {85}, pmid = {39994536}, issn = {1471-2180}, support = {111-2313-B-002-010//National Science and Technology Council/ ; }, abstract = {Enterococcus faecalis is a significant pathogen in healthcare settings and is frequently resistant to multiple antibiotics. This resistance is compounded by its ability to form biofilms, dense bacterial communities that are challenging to eliminate via standard antibiotic therapies. As such, targeting biofilm formation is considered a viable strategy for addressing these infections. This study assessed the effectiveness of surfactin, a cyclic lipopeptide biosurfactant synthesized by Bacillus subtilis natto NTU-18, in preventing biofilm formation by E. faecalis. Analytical characterization of surfactin was performed via liquid chromatography‒mass spectrometry (LC‒MS). Additionally, transcriptomic sequencing and quantitative PCR (qPCR) were used to investigate alterations in E. faecalis gene expression following treatment with surfactin. The data revealed notable suppression of crucial virulence-related genes responsible for pilus construction and exopolysaccharide synthesis, both of which are vital for E. faecalis adhesion and biofilm structure. Functional tests confirmed that surfactin treatment substantially reduced E. faecalis attachment to Caco-2 cell monolayers and curtailed exopolysaccharide production. Moreover, confocal laser scanning microscopy revealed significant thinning of the biofilms. These observations support the potential utility of surfactin as a therapeutic agent to manage biofilm-associated infections caused by E. faecalis.}, }
@article {pmid39992185, year = {2025}, author = {Lv, X and Liu, S and Cao, Y and Wu, H and Zhang, C and Huang, B and Wang, J}, title = {Multiwalled Carbon Nanotubes Promoted Biofilm Formation and Rhizosphere Colonization of Bacillus subtilis Tpb55.}, journal = {Journal of agricultural and food chemistry}, volume = {}, number = {}, pages = {}, doi = {10.1021/acs.jafc.4c10818}, pmid = {39992185}, issn = {1520-5118}, abstract = {Plant growth-promoting bacteria (PGPB) achieve effective colonization by forming a biofilm on the root surface. However, the promoting effects and mechanisms of nanomaterials on PGPB biofilm formation and rhizosphere colonization are rarely studied. This study investigated the effects and the potential mechanism of multiwalled carbon nanotubes (MWCNTs) on biofilm formation and rhizosphere colonization of PGPB Bacillus subtilis. 10 and 100 mg/L MWCNTs increased biofilm biomass, extracellular polymeric substance components, live/dead cell ratio, and spores in biofilms. MWCNTs induced B. subtilis Tpb55 upregulated gene expressions of malL, sacX, tasA-tapA, and epsA-O correlated with carbohydrate metabolism and biofilm formation. MWCNTs first stimulated Tpb55 flagellar motility and then increased biofilm formation, thus promoting colonization in the tobacco rhizosphere. Greenhouse experiments showed that the combination of MWCNTs and Tpb55 reduced the occurrence of tobacco black shank. Therefore, MWCNTs have broad application potential in enhancing the effectiveness of PGPB in agricultural disease control and yield enhancement.}, }
@article {pmid39991392, year = {2025}, author = {Yadav, S and Pawar, S and Patil, S}, title = {Inhibition of Pseudomonas aeruginosa Biofilm Formation Using Silver Nanoparticles.}, journal = {Cureus}, volume = {17}, number = {1}, pages = {e77848}, pmid = {39991392}, issn = {2168-8184}, abstract = {Background and aim Nanotechnology explores the unique properties of nanoparticles, which are very dissimilar from their bulk forms. Silver (Ag) has been exhibited to have antimicrobial and antibiofilm properties; since ancient times, silver has been used for its therapeutic qualities. Currently, medical research is investigating the activity and potential uses of silver nanoparticles (AgNPs). Pseudomonas aeruginosa is frequently seen in nosocomial settings because of its capacity to form biofilms on medical devices, implants, and instruments, which increases the risk of infection in hospitalized patients. When P. aeruginosa forms biofilms, it becomes more resistant to antimicrobials and can persist on medical equipment. Biofilms contribute to drug resistance and can drive the progression from acute to chronic diseases. Novel approaches can be aimed at a co-treatment strategy that mixes a drug that disrupts biofilms with conventional antibiotics, and this may make the biofilms more susceptible to treatment. In the present investigation, we study the antibiofilm effect of AgNPs against the biofilm production of P . aeruginosa. Materials and methods The study included 196 P . aeruginosa isolates from specimens at Krishna Hospital &amp; Medical Research Center, Karad. Identification (ID) and antibiotic susceptibility testing (AST) were done by using the VITEK 2 compact system (BioMérieux, France). Biofilm production and antibiofilm assays were evaluated using the tissue culture plate (TCP) method. Results Biofilm production was observed in 171 (87.24%) of isolates, with 25 (12.76%) being non-biofilm producers. Among biofilm producers, 91 (46.43%) were weak, 58 (29.59%) moderate, and 22 (11.22%) strong. At 400 µg/mL of AgNP concentration, 68 (85%) of isolates showed 60%-90% inhibition. Conclusions P . aeruginosa is a significant hospital-associated pathogen, as indicated by its isolation rate of 16.15%, emphasizing its clinical importance. Notably, 87% of isolates were biofilm producers. Nanotechnology, particularly AgNPs, presents promising solutions for combating biofilms, offering versatile and effective approaches for healthcare and industrial applications.}, }
@article {pmid39990851, year = {2024}, author = {Liang, L and Chen, X and Zhuang, W and Liu, Y and Zhao, W}, title = {[Research Progress on Drug Intervention to Inhibit Dental Plaque Biofilm Formation by Streptococcus mutans Based on the Concept of Ecological Prevention of Dental Caries].}, journal = {Sichuan da xue xue bao. Yi xue ban = Journal of Sichuan University. Medical science edition}, volume = {55}, number = {6}, pages = {1597-1603}, pmid = {39990851}, issn = {1672-173X}, mesh = {*Biofilms/drug effects ; *Streptococcus mutans/drug effects ; *Dental Plaque/microbiology/prevention &amp; control ; *Dental Caries/prevention &amp; control/microbiology ; Humans ; *Anti-Bacterial Agents/pharmacology ; }, abstract = {Dental caries is the local destruction of hard tooth tissue caused by acidic byproducts generated by cariogenic bacteria, primarily Streptococcus mutans, which ferment free sugars in the presence of host factors, dietary components, and environmental conditions. A main feature of dental caries is the formation of dental plaque biofilm, which significantly improves the resistance of bacteria to drugs and host immunity. Traditional anti-caries drugs mainly exert anti-biofilm functions indirectly through antibacterial activities. However, they tend to interfere with the symbiotic microbiota while inhibiting cariogenic bacteria, which may cause imbalance within the oral microbial system. With increasing attention paid to the homeostasis of oral microbiota, new types of anti-caries drugs have been developed, such as natural extracts, artificially synthesized small molecules, and oligonucleotides. They act on key targets to inhibit the formation of biofilm substrates or regulate the interactions between oral microorganisms, thereby efficiently inhibiting biofilm formation. These drugs do not have bactericidal effects. Nevertheless, they exert indirect antimicrobial effects by interfering with biofilm substrate formation or microbial interactions. The optimization of delivery carriers, combination drug therapy, and biomimetic design further enhance the efficacy of these new types of anti-caries drugs. This article provides a review of the prevention and treatment principles and key targets of dental plaque biofilm. We also discussed the types, mechanisms of action, and development trends of relevant drugs.}, }
@article {pmid39988682, year = {2025}, author = {Babanouri, N and Sahmeddini, S and Khadang, S and Bazargani, A}, title = {Effect of Xylitol and Fluoride Varnish on Biofilm and Saliva in Orthodontic Patients: A Triple-Blind Randomized Clinical Trial.}, journal = {Clinical and experimental dental research}, volume = {11}, number = {1}, pages = {e70062}, doi = {10.1002/cre2.70062}, pmid = {39988682}, issn = {2057-4347}, support = {//This study was supported by the Shiraz University of Medical Sciences (Grant no. 22740)./ ; }, mesh = {Humans ; *Xylitol/pharmacology ; *Biofilms/drug effects ; *Saliva/microbiology/chemistry ; Female ; Male ; *Fluorides, Topical/pharmacology/administration &amp; dosage ; Adolescent ; *Streptococcus mutans/drug effects ; *Cariostatic Agents/pharmacology ; Young Adult ; *Dental Caries/prevention &amp; control/microbiology ; Lactobacillus/drug effects ; Adult ; Orthodontic Brackets/microbiology/adverse effects ; Orthodontic Appliances, Fixed ; Sodium Fluoride/pharmacology/administration &amp; dosage ; }, abstract = {OBJECTIVES: Fixed orthodontic appliances are associated with higher levels of plaque and saliva bacteria, which contribute to dental caries. The effects of combining xylitol and fluoride, both used in caries prevention, are uncertain. Thus, this study assessed the combined impact of fluoride and xylitol varnish on bacteria in saliva and biofilms around orthodontic brackets.<br><br>MATERIALS AND METHODS: A single-center, four-arm, parallel-group, triple-blind, randomized clinical trial was conducted. A total of 120 patients who required fixed orthodontic treatment were included. Patients were sorted into one of the following groups at random: fluoride, xylitol, combined fluoride and xylitol, and control. Biofilm and saliva sampling was performed at two intervals: T0 (first session of bracket bonding, before application of the varnish) and T1 (6 weeks after application of the varnish). The number of Streptococcus mutans and Lactobacillus was counted using the CFU method.<br><br>RESULTS: The relative number of S. mutans and lactobacilli in saliva and biofilm significantly decreased following the application of fluoride and combined fluoride/xylitol varnish (p&#x2009;<&#x2009;0.05) and were more effective than xylitol varnish. There was no significant difference between fluoride and combined fluoride/xylitol varnishes regarding changes in S. mutans and Lactobacillus colonies in saliva and dental biofilms. Additionally, there was no significant difference between xylitol and the two other active varnishes regarding reduction in biofilm S. mutans and Lactobacillus.<br><br>CONCLUSION: There was no significant difference between fluoride and combined fluoride/xylitol varnishes regarding changes in the studied bacteria in saliva and dental biofilms, and they were more effective than xylitol varnish.<br><br>TRIAL REGISTRATION: The Iranian Registry of Clinical Trial identifier: IRCT20181121041713N4; https://fa.irct.ir/trial/58543.}, }
@article {pmid39987875, year = {2025}, author = {Pourrostami Niavol, K and Andaluri, G and Achary, MP and Suri, RPS}, title = {How does carbon to nitrogen ratio and carrier type affect moving bed biofilm reactor (MBBR): Performance evaluation and the fate of antibiotic resistance genes.}, journal = {Journal of environmental management}, volume = {377}, number = {}, pages = {124619}, doi = {10.1016/j.jenvman.2025.124619}, pmid = {39987875}, issn = {1095-8630}, abstract = {With the spread of antibiotic resistance genes (ARGs) in the environment, monitoring and controlling ARGs have become an emerging issue of concern in biological processes. Moving bed biofilm reactors (MBBR) have been gaining attention for application in wastewater treatment. Since the performance of MBBR depends on operational parameters and biocarriers, selection of suitable biocarriers and start-up conditions are vital for efficiency of MBBRs. This study investigates the effects of different carbon-to-nitrogen (C/N) ratios and carrier types on the fate of selected ARGs and microbial communities in four MBBR systems using two conventional (K3 and sponge biocarrier (SB)) and two modified carriers (Fe-Ca@SB and Ze-AC@SB). Results showed that the modified biocarriers achieved higher NH4-N removal and better simultaneous nitrification and denitrification (SND) performance (90%) at C/N of 20. However, as the C/N ratio decreased to 10 and 7, the performance of all bioreactors was approximately similar. Moreover, COD removal of 90% was achieved in all reactors regardless of C/N ratio and carrier type. Further studies on the fate of selected ARGs (tetA, blaTEM, ampR) showed that the C/N ratio could affect the abundance of target ARGs, especially for K3 biocarrier, with tetA being the most abundant gene. Also, as the C/N ratio decreased, intl1 was enriched using K3 and SB. However, for Ze-AC@SB, the increase in the abundance of ARGs and intl1 was the lowest making it a reliable carrier not only in MBBR performance but in the control of ARGs. Metagenomic studies showed that the C/N ratio and carrier type could alter the diversity and structure of the bacterial communities in different MBBR systems, with Proteobacteria being the most abundant phylum in all four systems.}, }
@article {pmid39987511, year = {2025}, author = {Samy, S and Alagumuthu, M and Yalamaddi, OD and Dangate, MS}, title = {New Chlorophenyl Dioxo-Imidazolidines for Bacterial Biofilm.}, journal = {Drug development research}, volume = {86}, number = {2}, pages = {e70054}, doi = {10.1002/ddr.70054}, pmid = {39987511}, issn = {1098-2299}, mesh = {*Biofilms/drug effects ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Imidazolidines/pharmacology/chemistry ; Gram-Negative Bacteria/drug effects ; Gram-Positive Bacteria/drug effects ; Topoisomerase II Inhibitors/pharmacology ; }, abstract = {Biofilm is a "growing" problem and needs effective remedial agents. Here we report novel methyl 4-((4-(4-chlorophenyl)-2,5-dioxoimidazolidin-1-yl) methyl) benzoate derivatives (5a-l) as antibiofilm and antimicrobial agents evaluated with both in silico and in vitro techniques. When it comes to Gram-positive bacterial strains like Staphylococcus aureus (MTCC 737), MRSA and Streptococcus pneumoniae (MTCC 1936), and Gram-negative bacterial strains like Pseudomonas aeruginosa (MTCC 424) and Escherichia coli (MTCC 443), the minimum inhibitory concentration (MIC), minimum biofilm inhibition concentration (MBIC), and anti-biofilm activity were measured. Out of all the compounds (5a-l), 5b and 5d showed no toxicity to mammalian cells and were equally active against various Gram-positive and Gram-negative bacteria at low concentrations (MIC: 0.1-9.5 µg/mL). Compounds 5b and 5d were also validated for the DNA gyrase inhibition potential as an antimicrobial mechanism of action in vitro. These compounds showed high level DNA gyrase inhibition potentials (IC50 0.025 µM, ≥ 98 relative % activity and 0.24 µM, ≥ 94 relative % activity respectively. In the end, we have identified 5b and 5d as most effective among 5a-l and are considered for further preclinical studies.}, }
@article {pmid39986790, year = {2025}, author = {Yang, H and Dong, P and Huo, S and Nychas, GE and Luo, X and Zhu, L and Mao, Y and Han, G and Liu, M and Liu, Y and Zhang, Y}, title = {Deciphering the inhibitory mechanisms of cinnamaldehyde on biofilm formation of Listeria monocytogenes and implement these strategies to control its transfer to beef surfaces.}, journal = {Food research international (Ottawa, Ont.)}, volume = {204}, number = {}, pages = {115946}, doi = {10.1016/j.foodres.2025.115946}, pmid = {39986790}, issn = {1873-7145}, mesh = {*Acrolein/analogs &amp; derivatives/pharmacology ; *Biofilms/drug effects/growth &amp; development ; *Listeria monocytogenes/drug effects/physiology ; *Red Meat/microbiology ; Animals ; Microbial Sensitivity Tests ; Food Microbiology ; Cattle ; Bacterial Adhesion/drug effects ; Anti-Bacterial Agents/pharmacology ; Virulence Factors/genetics/metabolism ; }, abstract = {Natural essential oils have received widespread attention as promising microbial inhibitors, whereas a comprehensive understanding of their mechanisms underlying biofilm control and impact on biofilm cross-contamination on meat remains poorly understood. In this study, Listeria monocytogenes (Lm) biofilms were treated with sub-inhibitory concentrations of cinnamaldehyde (CA) and characterized over a 4-day period. Both 1/2 MIC (160 μg/mL) and 1/4 MIC (80 μg/mL) CA delayed the development of Lm biofilm on abiotic surfaces and reduced the maximum biofilm formation. The limited effect of 1/4 MIC CA on the flagellar-mediated motility of Lm during initial adhesion indicated that hindering bacterial motility was not the main reason for CA inhibition of biofilm formation. Transcriptomics results showed that CA was involved in inhibitory pathways dominated by energy metabolism and peptidoglycan synthesis during the initial adhesion period and the maturation period of the biofilm, respectively. This posed an obstacle to the polymers required for biofilm cell adhesion and the energy consumption required for their production. Down-regulation of genes associated with multiple signalling systems and virulence factors also suggested that CA further mitigated resistance and virulence in residual biofilm cells. In addition, quantification of biofilm cells transferred to beef surfaces confirmed that CA significantly reduces the biomass transferred and the risk of persistent biofilm contamination. This study provided the theoretical basis for the control of Lm biofilm and its cross-contamination in the food industry by natural essential oils.}, }
@article {pmid39986621, year = {2025}, author = {Liu, Z and Liu, X and Wang, H and Man, S and Yan, Q}, title = {Ferrihydrite regulated nitrogen metabolic pathway at biocathode of bioelectrochemical system - Insight into biofilm formation and bacterial composition.}, journal = {Bioresource technology}, volume = {}, number = {}, pages = {132275}, doi = {10.1016/j.biortech.2025.132275}, pmid = {39986621}, issn = {1873-2976}, abstract = {To further understand the nitrogen metabolism disrupted by anthropogenic activities, 2.5 g/L of ferrihydrite were added into cathodic chamber of bioelectrochemical system to expediate the nitrogen removal process. It was found that the nitrate removal constant was significantly improved and maintained at around 0.09 h[-1] with ferrihydrite addition, while the control group maintained only at around 0.05 h[-1]. Besides, it seemed that the addition of ferrihydrite lead to less biomass accumulation but higher biofilm viability. Meanwhile, ferrihydrite selectively enriched OTUs capable of participating in both iron and nitrogen metabolism, relative abundance of OTU1631 (Thiobacillus) and OTU1467 (Comamonas granuli) was accordingly upped to 58.75 % and 5.11 %, respectively. Moreover, denitrification related genes were enhanced while genes related to nitrogen fixation, dissimilatory nitrate reduction, assimilatory nitrate reduction and nitrification were downregulated, further confirming the redirected electron transfer for the promotion of denitrification.}, }
@article {pmid39985993, year = {2025}, author = {Park, K and Kim, KY and Kirk, MF and Kwon, MJ}, title = {Biofilm development on fractured rock in oligotrophic nitrate-rich groundwater: An in-situ bioreactor study.}, journal = {Water research}, volume = {277}, number = {}, pages = {123329}, doi = {10.1016/j.watres.2025.123329}, pmid = {39985993}, issn = {1879-2448}, abstract = {Biofilms drive all biogeochemical processes and represent the main mode of existence for active microbial life. Many past studies examined biofilm formation under static and eutrophic conditions, but those conditions are not representative of typical groundwater environments. In this study, we developed in situ bioreactors and methodologies to examine the influence of subsurface properties such as redox condition and lithology on the properties of naturally formed biofilms in two adjacent wells, a 30-m deep well completed in alluvium and a 120-m deep well in gneiss bedrock. The bulk chemistry of groundwater from the wells was similar, with neutral pH and abundant nitrate (21.9-24.6 mg/L), but redox conditions differed with depth (alluvial: oxic, gneiss bedrock: anoxic). Microbial community analysis revealed distinct clustering of biofilm community composition with the groundwater environment. Biofilm communities were consistently assembled by deterministic processes whereas planktonic communities had a higher influence of stochastic processes. Alluvial biofilms exhibited more diverse communities mainly composed of organotrophic aerobes capable of nitrate utilization. Bedrock biofilms indicated similar community compositions with groundwater where anaerobic denitrifiers coupled with sulfur oxidizers were dominant. Visualization and biomass quantification revealed distinct morphologies and development of biofilm along rock types and groundwater environments. Biofilm on gneiss surface had more biomass and formed a thin layered structure, compared to sandstone biofilm which had a randomly distributed pattern, implying that the morphology of biofilm was governed by the properties of the rock. Attached to unattached (planktonic) microbe ratios ranged from 3.9 × 10[3] to 1.2 × 10[4]: 1 in the gneiss surface and 3.4 × 10[2] to 4.2 × 10[2]: 1 in the sandstone surface in bedrock groundwater environment. Taken together, this study advances our understanding of subsurface biomass abundance and demonstrates that the in-situ bioreactors are effective for cultivating and analyzing of subsurface biofilms. Based on the specific field conditions tested, we found that biofilm can form stably on fractured rock surfaces within a year, with groundwater redox conditions shaping community composition and rock types determining biofilm volume and morphology. The methodologies presented here can be extended to other subsurface environments with varying groundwater geochemistry and lithology, which will help further refine estimates of microbial life and its role in subsurface ecosystems.}, }
@article {pmid39985209, year = {2025}, author = {Yan, N and Zhou, H and He, J and Li, T and Liu, Q and Ning, H and Ma, Z and Feng, L and Jin, T and Deng, Y and Wu, Z and Kennard, SC}, title = {Correction to "A Multifunctional Cobalt-Containing Implant for Treating Biofilm Infections and Promoting Osteointegration in Infected Bone Defects Through Macrophage-Mediated Immunomodulation".}, journal = {Advanced science (Weinheim, Baden-Wurttemberg, Germany)}, volume = {}, number = {}, pages = {e2502472}, doi = {10.1002/advs.202502472}, pmid = {39985209}, issn = {2198-3844}, }
@article {pmid39984582, year = {2025}, author = {Xue, J and Meng, K and Lv, J and Liu, L and Duan, F and Ji, X and Ding, L}, title = {NlpD as a crucial factor in desiccation resistance and biofilm formation in Cronobacter sakazakii.}, journal = {Scientific reports}, volume = {15}, number = {1}, pages = {6289}, pmid = {39984582}, issn = {2045-2322}, support = {32200156//National Natural Science Foundation of China/ ; WJ2023M168//Hubei Province Health and Family Planning Scientific Research Project/ ; }, mesh = {*Cronobacter sakazakii/physiology/metabolism/genetics ; *Biofilms/growth &amp; development ; *Desiccation ; Bacterial Proteins/metabolism/genetics ; Proteomics/methods ; Bacterial Outer Membrane Proteins/metabolism/genetics ; Lipoproteins/metabolism/genetics ; Humans ; Hydrophobic and Hydrophilic Interactions ; }, abstract = {Cronobacter sakazakii is a Gram-negative bacterium known for causing severe infections in neonates, particularly through contaminated infant formula. This study investigated the role of the outer membrane lipoprotein NlpD in the environmental tolerance of C. sakazakii. A nlpD knockout mutant was constructed, and its impact on desiccation resistance, biofilm formation, motility, and proteomic profiles was evaluated and compared with that of the wild-type strain. The nlpD mutant presented reduced desiccation tolerance, reduced ability to form a biofilm, and altered surface hydrophobicity and motility patterns. The complemented strain restored these phenotypic changes, confirming that the observed effects were specifically due to the deletion of nlpD. Proteomic analysis revealed significant differential expression of proteins involved in metabolic and biosynthetic pathways upon nlpD deletion. These findings emphasize the multifaceted role of NlpD in enhancing the environmental tolerance of C. sakazakii, suggesting its importance in the resilience and survival of the bacterium in adverse conditions.}, }
@article {pmid39984428, year = {2025}, author = {Scott, E and Bullerjahn, GS and Burkhart, CG}, title = {The Role of Cutibacterium acnes Biofilm as a Biological Glue in Acne and Dandruff: Current Insights and Future Directions.}, journal = {International journal of dermatology}, volume = {}, number = {}, pages = {}, doi = {10.1111/ijd.17694}, pmid = {39984428}, issn = {1365-4632}, }
@article {pmid39983883, year = {2025}, author = {Bhowmik, B and Chowdhury, A and Bhuiyan, MNI and Afrin, S and Sarkar, R and Dey, SS and Siddique, S and Satter Miah, MA}, title = {Biofilm associated growth inhibition of XDR Escherichia fergusonii strain ACE12 isolated from soil.}, journal = {Microbial pathogenesis}, volume = {}, number = {}, pages = {107400}, doi = {10.1016/j.micpath.2025.107400}, pmid = {39983883}, issn = {1096-1208}, abstract = {Biofilm formation by bacteria is highly recognized for virulence factors resulting in their resistance to antimicrobials that lead to biofilm-associated infections. In this study, we isolated Escherichia fergusonii from soil, characterized its biofilm-associated growth, and evaluated the inhibitory potential of anti-biofilm compunds. Test isolate ACE12 was precisely identified as E. fergusonii based on the morphological and 16S rRNA gene sequence analysis. The antibiotic susceptibility pattern of ACE12 showed its resistance to β-Lactams, Aminoglycosides, Macrolides, Tetracycline, Trimethoprim, Vancomycin, &amp; Nitrofurans and on the basis of its resistant pattern the isolate was categorized as extensively drug-resistant (XDR) bacteria. In addition, the research isolate ACE12 was found to harbor four distinct antibiotic resistant genes including dfrA1, blaTem-1, tetC, and sul1, encoding the resistant determinants for trimethoprim, β-lactam, tetracycline, and sulfonamide antibiotics, respectively. Initial screening of biofilm formation by Congo-Red Agar (CRA) and Tube method demonstrated that E. fergusonii ACE12 is a biofilm-forming bacterium. The respective biofilm was characterized by estimating the optical density (OD595) of crystal violet (CV)-stained biofilm by Microtiter plate assay, confirming E. fergusonii as a strong biofilm former. Evaluation of anti-biofilm activity of metal salt of zinc (ZnSO4.7H2O), 1,1-Diphenyl-2-Picrylhydrazyl (DPPH), and two phenolic acids including tannic acid (TA) and trans-cinnamic acid (trans-CA) showed that ≥80% of biofilm was inhibited at their minimum inhibitory concentrations of 15-100 μg/ml for ZnSO4.7H2O, 250-500μg/ml for DPPH, 40-50μg/ml for TA, and 500-1000 μg/ml for Trans-CA. Additionally, at a concentration of 2500 μg/ml, ZnO-1 exhibited approximately 80% biofilm reduction whereas 70% biofilm was inhibited by ZnO-6. These findings exhibit that, the studied anti-biofilm compounds can effectively inhibit the biofilm associated growth of E. fergusonii.}, }
@article {pmid39983264, year = {2025}, author = {Lin, B and Hu, T and Xu, Z and Ke, Y and Zhang, L and Zheng, J and Ma, J}, title = {Stratified biofilm structure of MABR enabling efficient ammonia removal from aquaculture medicated bath wastewater.}, journal = {Water research}, volume = {277}, number = {}, pages = {123326}, doi = {10.1016/j.watres.2025.123326}, pmid = {39983264}, issn = {1879-2448}, abstract = {The presence of high concentrations of residual antibiotics in aquaculture medicated bath wastewater poses challenges to conventional biological nitrogen removal processes. Membrane aerated biofilm reactor (MABR), known for its energy efficiency and stratified biofilm structure that supports diverse ecological niches, was therefore introduced. Experimental results revealed that MABR achieved an exceptional NH4[+]-N removal efficiency of 98.2 ± 1.8 % even under high oxytetracycline exposure, attributed to the protective effects of the biofilm on functional bacteria colonized in the inner layer (e.g., ammonia- and nitrite-oxidizing bacteria). Genes mediating the nitrification process, such as amoA/B and nxrA, showed an overall upward trend, with the activation of efflux pumps synergistically constituting the microbial response. Conversely, total nitrogen removal efficiency decreased from 95.3 ± 2.5 % to 76.0 ± 8.8 %, despite enrichment of Denitratisoma oestradiolicum (14.5 %) and denitrifying bacterium clone NOA-1-C (41.7 %), likely due to limited expression of the narG gene. After ceasing oxytetracycline dosing and adjusting operational parameters, total nitrogen removal improved to 87.4 ± 5.8 %. The results of this study underscore the significance and resilience of MABR technology in the treatment of aquaculture medicated bath wastewater.}, }
@article {pmid39982329, year = {2025}, author = {Pinna, A and Donadu, MG and Dore, S and Serra, R and Sacchi, M and Boscia, G and Bozó, A and Kovács, R}, title = {In Vitro Activity of a New Ophthalmic Spray Containing Biosecur[®] Citrus Extract (Oftasecur[®]) Against Candida auris and Candida albicans and Preformed Biofilm on Contact Lenses.}, journal = {Vision (Basel, Switzerland)}, volume = {9}, number = {1}, pages = {}, doi = {10.3390/vision9010012}, pmid = {39982329}, issn = {2411-5150}, abstract = {We investigated the in vitro antifungal activity of a new commercial ocular spray containing Biosecur[®] citrus extract (Oftasecur[®]) against Candida auris and C. albicans and assessed its activity against preformed Candida biofilm on contact lenses and plastic lens cases. The C. auris isolate 12 (NCPF 8973) and the SC5314 C. albicans wild-type reference strain were used. Oftasecur[®]'s effect on C. auris and C. albicans planktonic cells (1 × 10[6] cells/mL) was tested in RPMI-1640 medium. The concentrations tested were 0.39%, 1.56%, 6.25%, 12.5%, and 25%. The living planktonic cell number was obtained using time-kill experiments. Antifungal activity against preformed C. auris and C. albicans biofilm on etafilcon A and senofilcon A contact lenses and plastic lens cases was also tested. A significant decrease was found in the living cell number of C. albicans after 8-48 h in the presence of Oftasecur[®] concentrations ranging from 6.25% to 25% (p < 0.01-0.001). In the C. auris experiments, the cell number was significantly decreased after 8 h incubation in 25% Oftasecur[®] (p < 0.05-0.001). Similarly, 12.5% Oftasecur[®] was effective against preformed C. auris and C. albicans biofilm on contact lenses and plastic lens cases. The results suggest that the in vitro antifungal activity of Oftasecur[®] against C. albicans and C. auris planktonic cells and preformed fungal biofilm on contact lenses and plastic cases is dependent on the concentrations used. Further research is warranted to establish whether Oftasecur[®] may play a role in the prevention of contact lens-related Candida keratitis and other ocular-surface Candida infections.}, }
@article {pmid39982113, year = {2025}, author = {Pejov, L and Hristovski, KD and Burge, SR and Burge, RG and Boscovic, D}, title = {Temporal dynamics of the biofilm-mediated open circuit potentials: Understanding the fundamentals via a combined thermodynamic and kinetic modeling approach.}, journal = {Biointerphases}, volume = {20}, number = {1}, pages = {}, doi = {10.1116/6.0003996}, pmid = {39982113}, issn = {1559-4106}, mesh = {*Biofilms/growth &amp; development ; *Thermodynamics ; Kinetics ; Electrodes ; Models, Theoretical ; }, abstract = {This study provides in-depth insights into the thermodynamics of electrochemical processes that govern the generation and temporal modulation of open-circuit potentials in biofilms and presents the foundation and applications of open-circuit potential methods to study the bioelectrochemical behaviors of biofilms. This investigation was guided by an overarching hypothesis that models should adequately explain the open-circuit potential patterns generated by biofilms when environmental conditions change; and from this work, a generalized model of electrochemical processes endemic to the biofilm electrode was developed and validated. The proposed model accounts for open system thermodynamics and the kinetics of bioelectrochemical transformations, and the model is simplified to enable applicability to a wide range of processes that are possible within biofilms. As such, the model can account for different parameters associated with various biofilm systems and is extendable to include numerous other experimental conditions. The model predictions were compared to the experimental data generated by 48 equidistantly located microbial potentiometric sensor electrodes in a chamber capable of simulating naturally occurring water matrix, which was exposed to environmental conditions. By combining electrochemical-cell thermodynamics and kinetics approaches, the model explained the temporal dependences of the open circuit potentials in aerobic and anaerobic conditions and the interconversion of two regimes commonly observed in natural systems. At the same time, it enables extraction of the relevant kinetic parameters from experimentally measured time evolution of the open circuit potentials.}, }
@article {pmid39982068, year = {2025}, author = {Reichhardt, C and Matwichuk, ML and Lewerke, LT and Jacobs, HM and Yan, J and Parsek, MR}, title = {Non-disruptive matrix turnover is a conserved feature of biofilm aggregate growth in paradigm pathogenic species.}, journal = {mBio}, volume = {}, number = {}, pages = {e0393524}, doi = {10.1128/mbio.03935-24}, pmid = {39982068}, issn = {2150-7511}, abstract = {UNLABELLED: Bacteria form multicellular aggregates called biofilms. A crucial component of these aggregates is a protective matrix that holds the community together. Biofilm matrix composition varies depending upon bacterial species but typically includes exopolysaccharides (EPS), proteins, and extracellular DNA. Pseudomonas aeruginosa is a model organism for the study of biofilms, and in non-mucoid biofilms, it uses the structurally distinct EPS Psl and Pel, the EPS-binding protein CdrA, and eDNA as key matrix components. An interesting phenomenon that we and others have observed is that the periphery of a biofilm aggregate can be EPS-rich and contain very few cells. In this study, we investigated two possible models of assembly and dynamics of this EPS-rich peripheral region: (i) newly synthesized EPS is inserted and incorporated into the existing EPS-rich region at the periphery during biofilm aggregate growth or (ii) EPS is continuously turned over and newly synthesized EPS is deposited at the outermost edge of the aggregate. Our results support the latter model. Specifically, we observed that new EPS is continually deposited at the aggregate periphery, which is necessary for continued aggregate growth but not aggregate stability. We made similar observations in another paradigm biofilm-forming species, Vibrio cholerae. This pattern of deposition raises the question of how EPS is retained. Specifically, for P. aeruginosa biofilms, the matrix adhesin CdrA is thought to retain EPS. However, current thinking is that cell-associated CdrA is responsible for this retention, and it is not clear how CdrA might function in the relatively cell-free aggregate periphery. We observed that CdrA is enzymatically degraded during aggregate growth without negatively impacting biofilm stability and that cell-free CdrA can partially maintain aggregation and Psl retention. Overall, this study shows that the matrix of P. aeruginosa biofilms undergoes both continuous synthesis of matrix material and matrix turnover to accommodate biofilm aggregate growth and that cell-free matrix can at least partially maintain biofilm aggregation and EPS localization. Furthermore, our similar observations for V. cholerae biofilms suggest that our findings may represent basic principles of aggregate assembly in bacteria.<br><br>IMPORTANCE: Here, we show that, to accommodate growing cellular biomass, newly produced Psl is deposited over existing Psl at the periphery of biofilm aggregates. We demonstrated that V. cholerae employs a similar mechanism with its biofilm matrix EPS, VPS. In addition, we found that the protease LasB is present in the biofilm matrix, resulting in degradation of CdrA to lower molecular weight cell-free forms. We then show that the released forms of CdrA are retained in the matrix and remain functional. Together, our findings support that the P. aeruginosa biofilm matrix is dynamic during the course of aggregate growth and that other species may employ similar mechanisms to remodel their matrix.}, }
@article {pmid39981044, year = {2025}, author = {Kokilakanit, P and Dungkhuntod, N and Serikul, N and Koontongkaew, S and Utispan, K}, title = {Caffeic acid phenethyl ester inhibits multispecies biofilm formation and cariogenicity.}, journal = {PeerJ}, volume = {13}, number = {}, pages = {e18942}, pmid = {39981044}, issn = {2167-8359}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Caffeic Acids/pharmacology ; *Phenylethyl Alcohol/analogs &amp; derivatives/pharmacology ; *Streptococcus mutans/drug effects ; *Dental Caries/microbiology/prevention &amp; control ; *Anti-Bacterial Agents/pharmacology ; Streptococcus oralis/drug effects ; Streptococcus mitis/drug effects ; Humans ; Microbial Sensitivity Tests ; Bacterial Adhesion/drug effects ; }, abstract = {BACKGROUND: Caffeic acid phenethyl ester (CAPE), a natural phenolic compound, has demonstrated antibacterial effects. Dental caries etiology is multifactorial, including a cariogenic biofilm containing multispecies bacteria. However, the antibacterial property of CAPE on multispecies biofilm is unclear. The aim of this study was to assess the effect of CAPE on the formation and cariogenicity in biofilm containing Streptococcus mutans, Streptococcus oralis, and Streptococcus mitis.<br><br>METHODS: S. mutans (ATCC 25175), S. oralis (ATCC 35037), and S. mitis (ATCC 49456T) were employed in this investigation. Each bacterial strain was cultured in the presence of CAPE, followed by susceptibility assessment through optical density measurements at a 600 nm wavelength. Multispecies biofilm formation was achieved by co-culturing S. mutans, S. oralis, and S. mitis at a 1:1:1 ratio on hydroxyapatite-coated 96-well plates. The anti-adherence activity of CAPE on multispecies biofilm was evaluated using a crystal violet staining assay. Cariogenic gene expression level and glucosyltransferase (GTF) function in CAPE-treated mixed bacteria were evaluated using real-time PCR and enzyme activity assay, respectively. The thickness and bacterial viability in CAPE-treated multispecies biofilm were examined using confocal laser scanning microscopy.<br><br>RESULTS: CAPE demonstrated a significant antimicrobial effect on S. mutans, S. oralis, and S. mitis (p < 0.05). The inhibition concentration 50% (IC50) of CAPE against S. mutans, S. oralis, and S. mitis ranged from 1.6-6.4 mg/ml. CAPE significantly hindered the multispecies biofilm adherence (p < 0.05). Furthermore, the expression of genes involved in acidogenicity, aciduricity, sucrose-dependent adhesion and quorum sensing mechanism and GTF activity were significantly decreased in CAPE-treated mixed bacteria (p < 0.05). In a multispecies biofilm, CAPE significantly reduced its thickness and viable bacteria population (p < 0.05). In conclusion, CAPE exhibited antimicrobial, anti-adherence and anti-cariogenic effects within a multispecies biofilm. These findings suggest the potential use of CAPE as an adjunctive anti-cariogenic agent in future dental applications.}, }
@article {pmid39980138, year = {2025}, author = {Abushahba, F and Algahawi, A and Areid, N and Vallittu, PK and Närhi, T}, title = {Efficacy of biofilm decontamination methods of dental implant surfaces: A systematic review of in vitro studies.}, journal = {European journal of oral sciences}, volume = {}, number = {}, pages = {e70005}, doi = {10.1111/eos.70005}, pmid = {39980138}, issn = {1600-0722}, abstract = {This systematic review examines the decontamination techniques used to clean titanium (Ti) implant surfaces covered with in vitro bacterial biofilms. The selected studies were gathered from the PubMed and Web of Science databases. These include in vitro studies investigating decontamination methods used to clean Ti implant surfaces coated with bacterial biofilms until January 2024. The determined studies were filtered according to the PRISMA guidelines, and the Science in Risk Assessment and Policy (SciRAP) was used to assess the reporting and methodological quality of the included studies. A total of 634 full-length peer-reviewed articles were identified. After excluding duplicate papers between the databases and screening according to the predefined inclusion and exclusion criteria, 13 studies were included. The decontamination methods investigated included mechanical, chemical, and physical methods, either as a single or in a combined approach. Significant variability was observed among the included studies. Combining the mechanical and physical methods with a chemical yielded the most significant reduction in both single- and multiple-species biofilms. The current results do not indicate that any single decontamination technique is more effective than others in eradicating bacterial biofilm from Ti surfaces; the combined approach was more advantageous than the single ones.}, }
@article {pmid39979667, year = {2025}, author = {Hong, WQ and Lee, WH and Musa, SH and Kamaruzaman, NA and Loo, CY}, title = {Evaluation of hydrogel loading with curcumin and silver nanoparticles: biocompatibilities and anti-biofilm activities.}, journal = {Biometals : an international journal on the role of metal ions in biology, biochemistry, and medicine}, volume = {}, number = {}, pages = {}, pmid = {39979667}, issn = {1572-8773}, support = {FRGS/1/2020/STG01/UNIKL/02/4//Ministry of Higher Education (MOHE) Malaysia, Fundamental Research Grant Scheme/ ; }, abstract = {Chronic wound healing is associated with prolonged elevated inflammation and high levels of oxidative stress leading to cell death. The majority of wounds are colonized with antibiotic-resistant bacterial biofilms such as Pseudomonas aeruginosa and Staphylococcus aureus. An ideal wound treatment should include agents with antioxidant, anti-inflammatory, and antibiofilm behavior. Therefore, in this study, a combination of curcumin nanoparticle (Cur-NP) and silver nanoparticle (AgNP) (Cur-NP/AgNP) loaded PVA hydrogel was used to inhibit the bacterial attachment and subsequent biofilm formation of P. aeruginosa and S. aureus. Cur was known for its antioxidant and anti-inflammatory effect while being non-toxic to cells. Meanwhile, AgNP demonstrated superior anti-bacterial and antibiofilm activities against both P. aeruginosa and S. aureus. Cur-NP/AgNP loaded PVA hydrogels completely inhibited the bacterial attachment and biofilm formation, possibly due to synergistic effect of Cur-NPs and AgNPs in killing the bacterial cells. It should be highlighted that no surviving bacterial cells were noted for Cur-NP/AgNP loaded hydrogels. On the other hand, AgNPs or Cur-NPs alone loaded hydrogels were unable to achieve complete inhibition of biofilm formation, even though significant reduction in the biofilm mass was noted compared with control samples. Cur-NP and AgNP exerted oxidative-stress induced cell death in HaCaT cells via mitochondrial dysfunction, mitochondrial membrane potential (MMP) reduction, adenosine triphosphate inhibition, and increased cytochrome C release. The toxicity of formulation followed the decreasing trend: Cur-NP/AgNP < AgNPs alone < Cur-NPs alone. Taken together, the combination of Cur-NP/AgNP completely inhibited bacterial biofilm formation through bactericidal effect on the planktonic cells while exerted the least toxic effects towards skin cells.}, }
@article {pmid39978626, year = {2025}, author = {Dai, H and Zhong, Y and Xiang, S and Dong, S and Chen, S}, title = {Biofilm colonization on non-degradable and degradable microplastics change the adsorption of Cu(II) and facilitate the dominance of pathogenic microbes.}, journal = {Environmental research}, volume = {}, number = {}, pages = {121169}, doi = {10.1016/j.envres.2025.121169}, pmid = {39978626}, issn = {1096-0953}, abstract = {Microplastics (MPs) have become a global concern as they can accumulate pollutants in aquatic environments. In this research, Cu(II) and non-degradable (polyamide, PA), degradable (polylactic acid, PLA) MPs were employed to reveal the potential connection among different aged MPs and heavy metal pollutants. The aging processes of MPs induced alterations in the surface morphologies, led to an augmentation of the specific surface area, and formed more biofilm and oxygen-containing groups on the MPs surface. The Qe of PA and PLA MPs increased from 0.102 and 0.989 to 1.192 and 2.457 mg/g after aging, respectively. The analysis of site energy distribution further verified that the enhanced adsorption capacity resulted from more high-energy adsorption sites obtained during the aging processes of MPs. Moreover, pathogenic bacteria and resistant bacteria were accumulated on the surface of MPs regardless of the aging environment, and the abundance and diversity of pathogenic bacteria on the biofilm of the PA surface were greater than those on the PLA MPs. This research offers an insight into the mechanism underlying microbial colonization and adsorption in the relationship between MPs and Cu(II), which is beneficial for judging the enrichment of heavy metals on MPs within the aquatic environment.}, }
@article {pmid39978299, year = {2025}, author = {Wang, J and Dong, Q and Chen, X and Feng, B and Qu, Y and Lin, T and Bai, Y and Liu, P and Zhou, C and Suo, Y}, title = {Potential genetic markers of biofilm formation ability by Listeria monocytogenes isolated from fresh agricultural products.}, journal = {International journal of food microbiology}, volume = {433}, number = {}, pages = {111118}, doi = {10.1016/j.ijfoodmicro.2025.111118}, pmid = {39978299}, issn = {1879-3460}, abstract = {The ability of Listeria monocytogenes to form biofilms is the key to its persistence in the food industry. Biofilm phenotype assessment is mainly based on physical and chemical methods, which are time-consuming. The aim of this study was to analyze genetic differences in the biofilm-forming ability of L. monocytogenes, found potential genetic markers, and quickly determined the biofilm phenotype. In particular, 103 strains of L. monocytogenes from agricultural products, were evaluated through multilocus sequence typing and their biofilm formation assays. The genetic characteristics of 12 representative strains were analyzed by comparative genomics, and the relevant genetic characteristics of the 103 strains were verified by polymerase chain reaction technology. The 103 strains were divided into 22 sequence types (STs), and top six types were ranked from high to low according to the median of biofilm biomass as follows: ST91, ST87, ST8, ST9, ST121, ST155, and all of them exhibited 2-3 biofilm phenotypes (strong, medium and weak). Comparative genomics analysis and verification identified the vip gene as a preliminary genetic marker for biofilm phenotypes, and the accuracy of determination can be improved by combining vip with 1-3 genes (srmB, cycB, and uvrB) or STs (ST8, ST87, and ST121). In addition, the smc_4, srmB-inlH, inlH and ssbA genes could accurately distinguish the phenotypes of ST9, ST155, ST91 and other STs. These genetic markers could be used as key targets for rapid determination of the biofilm phenotype of L. monocytogenes, thereby providing useful guidance for the optimization of disinfection processes in the food industry.}, }
@article {pmid39978059, year = {2025}, author = {Huang, S and Wang, H and Tang, Y and Wang, Z and Li, G and Li, D}, title = {New insights into the assembly processes of biofilm microbiota communities: Taking the world's largest water diversion canal as a case study.}, journal = {The Science of the total environment}, volume = {968}, number = {}, pages = {178827}, doi = {10.1016/j.scitotenv.2025.178827}, pmid = {39978059}, issn = {1879-1026}, abstract = {Systematic studies on the assembly process and drivers of biofilm microbiota communities are still limited. In this study, we used the artificial concrete channel of the world's largest interbasin water diversion project, the middle route of the South-to-North Water Diversion Project in China, as a model system to investigate the assembly mechanisms of biofilm microbiota communities. Our study revealed that water temperature (p < 0.001) and hydrodynamic disturbance (p < 0.05) significantly influenced biofilm biomass. The bacterial communities exhibited substantial spatial heterogeneity, whereas the eukaryotic communities presented pronounced spatial and seasonal variations (PERMANOVA, p < 0.05). Neutral model and null model analyses indicated that dispersal limitation and homogeneous selection (54.8 %-69.7 % in bacteria and 55.9 %-76.1 % in eukaryotes) predominantly governed community assembly. Deterministic effects such as hydrodynamic conditions and temperature strongly influence eukaryotes (homogeneous selection accounts for 63.9 % of eukaryotes in spring). The metacommunity network could be divided into five primary modules with key nodes, including many species from Proteobacteria, Chlorophyta, Bacillariophyta, and Cyanobacteria. Bacteria, such as Proteobacteria, Chlorophyta, Cyanobacteria, and Bacteroidota, act as connectors and a vital role in maintaining the coexistence of modules. Finally, we confirmed that physicochemical (hydrodynamic conditions, temperature, dissolved oxygen conductivity permanganate index), spatial, and biological factors have significant effects on both bacterial and eukaryotic communities as well as metacommunity networks. Our findings provide new insights into the different assembly processes and drivers of bacterial and eukaryotic communities in biofilms, which is highly important for water quality monitoring and sustainable water diversion.}, }
@article {pmid39976031, year = {2025}, author = {Shilpi, JA and Sarker, DK and Seidel, V and Ali, MT and Uddin, SJ and Basak, A and Chakraborty, S and Khairuzzaman, M and Nahar, AU and Salam, FBA}, title = {In vitro Antibiofilm Activity-directed In silico Identification of Natural Products Targeting Bacterial Biofilm Regulators SarA and LasR.}, journal = {Current pharmaceutical biotechnology}, volume = {}, number = {}, pages = {}, doi = {10.2174/0113892010348855241113031323}, pmid = {39976031}, issn = {1873-4316}, abstract = {BACKGROUND: Antibiofilm agents serve as an essential tool in the fight against antibiotic resistance, and natural products provide a promising source for potential drug leads.<br><br>OBJECTIVE: This study investigates the activity of twenty Bangladeshi medicinal plants against Staphylococcus aureus and Pseudomonas aeruginosa biofilms and predicts the interactions of selected phytochemicals from five of the best performing plants with the active sites of transcriptional regulatory proteins SarA of S. aureus and LasR of P. aeruginosa.<br><br>METHODS: The plant extracts were tested by microtiter plate-based assay against S. aureus and P. aeruginosa biofilms. Molecular docking and molecular dynamics simulation (MD) were conducted using PyRx and GROMACS, respectively.<br><br>RESULTS: The best activity was identified for Cassia fistula and Ananas comosus, showing &#x2265; 75% inhibition of biofilm formation. ent-Epicatechin-(4&#x3b1;&#x2192;8)-epiafzelechin (EEE) of C. fistula, cyanidin-3,3',5-tri-O-&#x3b2;-D-glucopyranoside (CTG) of A. comosus, and 7-O-(4-hydroxy-Ecinnamoyl)- spinoside of A. spinosus showed the best predictive binding affinity (-7.6, -7.6 and - 7.7 kcal/mol, respectively) for SarA. EEE was the only ligand to exhibit a stable ligand-protein complex with SarA in the MD simulation of 200 ns (binding energy of MMPBSA analysis - 39.899 kJ/mol). Chrysophanol, epicatechin and physcion, of C. fistula (-10.5, -10.5, and -11.0 kcal/mol, respectively) and auraptene of F. limonia (-10.8 kcal/mol) showed the best predictive binding affinity for LasR. Epicatechin showed the most stable ligand-protein complex with LasR (binding energy of MMPBSA analysis -63.717 kJ/mol).<br><br>CONCLUSION: Epicatechin and its derivative EEE could be used as scaffolds for the d evelopment of new antibiofilm agents against P. aeruginosa and S. aureus, respectively.}, }
@article {pmid39974957, year = {2025}, author = {Antypas, H and Schmidtchen, V and Staiger, WI and Li, Y and Tan, RJW and Ng, KKF and Neo, CJY and Radhesh, SM and Tanoto, FR and da Silva, RAG and Colomer Winter, C and Manzano, C and Wong, JJ and Pethe, K and Hasse, B and Brugger, SD and Wong, SL and Van Tyne, D and Zinkernagel, AS and Kline, KA}, title = {Fsr quorum sensing system restricts biofilm growth and activates inflammation in enterococcal infective endocarditis.}, journal = {bioRxiv : the preprint server for biology}, volume = {}, number = {}, pages = {}, doi = {10.1101/2025.02.07.636843}, pmid = {39974957}, issn = {2692-8205}, abstract = {Infective endocarditis (IE) is a life-threatening biofilm-associated infection, yet the factors driving biofilm formation remain poorly understood. Here, we identified the Fsr quorum sensing (QS) system of Enterococcus faecalis as a potent negative regulator of IE pathogenesis. Using microfluidic and in vivo models, we show that Fsr is induced in late IE when bacteria become shielded from blood flow. Deleting Fsr altered biofilm metabolism and promoted robust biofilm growth and gentamicin tolerance in vivo. Furthermore, Fsr inactivation attenuated inflammation by disrupting IL-1β cleavage and activation via the Fsr-regulated gelatinase (gelE), allowing biofilm to grow unchecked by the immune system. Consistent with our pre-clinical findings, analysis of two IE patient cohorts linked naturally occurring Fsr-deficient E. faecalis to prolonged bacteremia. Overall, our findings provide insights into the role of QS in biofilm growth, persistence, and immune evasion in enterococcal IE.}, }
@article {pmid39974278, year = {2025}, author = {Javadi, K and Ghaemian, P and Baziboron, M and Pournajaf, A}, title = {Investigating the Link Between Biofilm Formation and Antibiotic Resistance in Clinical Isolates of Acinetobacter baumannii.}, journal = {International journal of microbiology}, volume = {2025}, number = {}, pages = {1009049}, pmid = {39974278}, issn = {1687-918X}, abstract = {Background: Acinetobacter baumannii has become a significant problem in hospitals worldwide during the last decades. Biofilm formation is a virulence factor that may affect antibiotic resistance. This study aimed to elucidate the correlation between biofilm formation and biofilm-related and oxacillinase genes in A. baumannii clinical isolates. Methods: This study was conducted on 53 A. baumannii isolates collected from hospitals affiliated with Babol University of Medical Sciences (Babol, Iran) from April to October 2023. Kirby-Bauer disc diffusion was used to determine antibacterial resistance. Biofilm formation was examined using crystal violet staining. Polymerase chain reaction was used to detect oxacillinase (bla OXA-23, bla OXA-24, bla OXA-51, and bla OXA-58) and biofilm-encoding (bap and bla PER-1) genes using specific primers. Results: The strains showed the highest resistance to trimethoprim/sulfamethoxazole and ciprofloxacin (98.11%) and the lowest resistance to ampicillin/sulbactam (66.03%). All isolates formed biofilms. Also, 67.92%, 18.86%, and 11.32% were strong, moderate, and weak biofilm producers, respectively. The frequencies of bla OXA-23, bla OXA-24, bla OXA-51, bap, and bla PER-1 genes were 92.45%, 71.69%, 100%, 73.58%, and 58.49%, respectively. None of the isolates harbored bla OXA-58. Conclusions: A high prevalence of antibiotic-resistant strains was found among A. baumannii clinical isolates. There was no significant correlation between the clinical sample type and biofilm formation, but a notable link was found between antimicrobial resistance and biofilm formation, except for ciprofloxacin. Oxacillinase genes were not significantly correlated with biofilm formation, but biofilm production was associated with bap rather than bla PER-1. Understanding the A. baumannii biofilm formation process is crucial for effective control of associated infections by targeting this mechanism.}, }
@article {pmid39971954, year = {2025}, author = {Adami, GR and Li, W and Green, SJ and Kim, EM and Wu, CD}, title = {Ex vivo oral biofilm model for rapid screening of antimicrobial agents including natural cranberry polyphenols.}, journal = {Scientific reports}, volume = {15}, number = {1}, pages = {6130}, pmid = {39971954}, issn = {2045-2322}, mesh = {*Biofilms/drug effects ; Humans ; *Polyphenols/pharmacology ; *Vaccinium macrocarpon/chemistry ; Saliva/microbiology ; Microbial Sensitivity Tests ; Anti-Bacterial Agents/pharmacology ; Mouth/microbiology ; Anti-Infective Agents/pharmacology ; Plant Extracts/pharmacology ; Male ; Female ; Adult ; }, abstract = {The search has been ongoing for safe and effective antimicrobial agents for control and prevention of oral biofilm associated with disease. Clinical trials for oral specific anti-bacterials are costly and often provide inconclusive results. The simple approach of ex vivo testing of these agents has not demonstrated utility, likely due to variability of effects observed even with a single donor. We show how shed oral biofilms, easily obtained from donor saliva, and tested under optimized conditions, respond reproducibly to anti-bacterial challenges measured by reductions in rRNA accumulation in susceptible taxa. Responses are in part donor specific, but many bacteria taxa were shown to be reproducibly susceptible over a group of donors. For two antibiotics, vancomycin and penicillin G tested at pharmacologic levels, a subset of Gram-positive bacteria was inhibited. A natural product with antibacterial properties, diluted Vaccinium macrocarpon (cranberry) juice, was shown to inhibit a range of oral taxa, including Alloprevotella sp__HMT_473, Granulicatella adiacens, Lachnoanaerobaculum umeaense, Lepotrichia sp__HMT_215, Peptostreptococcus stomatis, Prevotella nanceiensis, Stomatobaculum sp__HMT_097, Veillonella parvula, and kill some targets. The model discussed in this study has promise as a rapid, precise, and reproducible ex vivo method to test and identify potential clinically useful antimicrobial agents active against the oral biofilm community.}, }
@article {pmid39968375, year = {2025}, author = {Cadenas-Jiménez, I and Rybtke, ML and Higazy, D and Martí-Martí, S and Tolker-Nielsen, T and Ciofu, O and Høiby, N}, title = {Co-culture biofilm patterns among different Pseudomonas aeruginosa clones from cystic fibrosis patients.}, journal = {Biofilm}, volume = {9}, number = {}, pages = {100257}, pmid = {39968375}, issn = {2590-2075}, abstract = {BACKGROUND: Pseudomonas aeruginosa chronic lung infection is the leading cause of death in the cystic fibrosis (CF) population. The high genome versatility of this microorganism allows it to adapt to the hostile CF lung where the same clone can persist for decades. Paranasal sinuses serve as a reservoir for bacterial adaptation before lung infection. Our study investigates biofilm compatibility among identical and different P. aeruginosa genotypes from sinus and lungs of CF patients. Strains were further characterized by whole genome sequencing and motility assays were performed.<br><br>METHODOLOGY: Motility, gentamicin susceptibility and growth rates were assessed in four strains coming from three CF patients. The strains were subjected to whole genome sequencing with the Illumina MiSeq platform.Conjugation assays using the mini Tn7 transposon were performed in order to tag bacteria with the fluorescent proteins YFP (yellow) and CFP (cyan). Biofilm experiments were carried out in a flow cell system and images were acquired using a confocal laser microscope (CLSM) on days 3 and 5. Four experiments were performed: Experiment 1 with two clonal isolates from sinus and lungs from patient P01 (CF430-142, CF430-11621); experiments 2 (CF430-11621&#xa0;+&#xa0;75885-B) and 3 (CF430-11621&#xa0;+&#xa0;80271-B) with two lung isolates belonging to two different clones from different patients (P02, P03) and experiment 4 with one lung strain (CF430-11621) and P. aeruginosa PAO1 reference strain.<br><br>RESULTS: P. aeruginosa clonal isolates coming from paranasal sinuses and lungs from the same patient were able to form mixed biofilm. When different clones were employed no mixed biofilms were observed. Similar results were observed when combining the lung strain and the reference strain PAO1. Biofilms of both strains were observed in the flow-cell channels but no mixed biofilms of them were observed, with the exception of strain 75887-B which did not appear to form any biofilm when mixed with strain CF430-11621. All strains performed swarming while strains CF430-142 and 75887B lacked twitching motility. An aminoacidic change in SadB was observed in the strain 75887B.<br><br>CONCLUSION: Mixed biofilms were only observed when identical clones from the same patient were cultured together. Our experiments indicate that twitching motility does not significantly affect biofilm formation or architecture in our isolates.}, }
@article {pmid39968128, year = {2025}, author = {Zhao, L and Sun, M and Lyu, C and Meng, L and Liu, J and Wang, B}, title = {Polyhydroxyalkanoate production during electroactive biofilm formation and stabilization in wetland microbial fuel cells for petroleum hydrocarbon bioconversion.}, journal = {Synthetic and systems biotechnology}, volume = {10}, number = {2}, pages = {474-483}, pmid = {39968128}, issn = {2405-805X}, abstract = {This study presented new insights into the sustainable conversion of total petroleum hydrocarbon (TPHC) into polyhydroxyalkanoates (PHAs) using wetland microbial fuel cells (WMFCs). The main innovations included the following two points: (1) The integration of bioelectricity generation with efficient PHA production further underscored the potential of electroactive biofilms as a sustainable platform for simultaneous TPHC biotransformation, bioelectricity recovery and PHA production. (2) The interactive dynamics of PHAs, metabolites, extracellular polymeric substances (EPS) and microorganisms during the formation and stabilization of electroactive biofilms provided novel insights into microbial strategies for carbon utilization. As the electroactive biofilm formed and stabilized, the current density enhanced significantly from 0 to 101 mA m[-] [2], then stabilized, and finally dropped to 3.51 mA m[-2]. Similarly, the power density showed a trend of increasing in the initial stage, maintaining in the middle stage, and then descending in the later stage. The production of six types of PHAs was identified: poly(3-hydroxybutyrate) [P(3HB)], poly(3-hydroxyvalerate) [P(3HV)], poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)], poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate] [P(3HB-co-3HHX)], poly(3-hydroxyhexadecanoate) [P(3HHD)] and poly(3-hydroxyoctadecanoate) [P(3HOD)], highlighting the metabolic flexibility of electroactive biofilms. The total PHA content was initially undetectable (days 0-4), gradually increased (days 4-28), rose rapidly (days 28-48), gradually increased and descended (days 48-68). The maximum PHA content of 0.664 g g[-][1] DCW achieved highlighted the dual functionality of WMFCs in bioelectricity production and PHA biosynthesis, distinguishing it from conventional MFC applications. The TPHC biodegradation ratio demonstrated a gradual increase (days 0-28), with a more pronounced rise (days 28-48), and a gradual rise to 76.1 % (days 48-68). Throughout the process, the metabolite volatile fatty acids (VFAs) produced were primarily acetate, propionate, butyrate and valerate. The trend of VFA production from days 0-56 closely followed that of TPHC biodegradation. The trend of tyrosine/tryptophan proteins in EPS was aligned with that of biofilm thickness. The strong correlation between the increase in the biofilm thickness and the intensity and peak height of tyrosine/tryptophan proteins during the first 20 days suggested that these proteins were integral to the structural integrity of the biofilms, and from days 20-64, the minimal variation in their intensity and peak height indicated that the biofilms had reached a relatively stable state. The biofilms in turn provided a stable microbial substrate and energetic support for the subsequent efficient synthesis of PHA. During the early phase, the dual-function bacteria, such as Pseudomonas, Bacillus, Acinetobacter and Desulfosarcina, prioritized electron transfer and bioelectricity production using available carbon sources. As bioelectricity generation became less critical in the later phase, the bacteria shifted to intracellular PHA accumulation, transitioning from bioelectricity production to PHA biosynthesis. Finally, a comprehensive network connecting functional microorganisms with bioelectricity production, PHA content, TPHC biodegradation, VFA production and EPS peak height was established. Overall, these findings provided valuable insights into the dynamic interactions and metabolic strategies of electroactive biofilms in WMFCs, highlighting their potential for the efficient bioconversion of PHCs into PHAs.}, }
@article {pmid39965710, year = {2025}, author = {Qiu, H and Zhao, W and Qin, Y and Wang, Y and Bai, M and Su, S and Wang, C and Zhao, Z}, title = {Ammonia-oxidizing activity and microbial structure of ammonia-oxidizing bacteria, ammonia-oxidizing archaea and complete ammonia oxidizers in biofilm systems with different salinities.}, journal = {Bioresource technology}, volume = {}, number = {}, pages = {132248}, doi = {10.1016/j.biortech.2025.132248}, pmid = {39965710}, issn = {1873-2976}, abstract = {Ammonia-oxidizing activity of different ammonia-oxidizing microorganisms (AOMs), such as ammonia-oxidizing bacteria (AOB), ammonia-oxidizing archaea (AOA), and complete ammonia oxidizers (comammoxs), were investigated by adding the inhibitors such as 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide, octyne, and KCLO3 in biofilm systems with different salinities. It was found that the ammonia-oxidizing activity of all AOMs gradually decreased with increasing salinity. The ammonia-oxidizing activity of AOB was consistently higher than those of AOA and comammox at different salinities. Moreover, nitrite-oxidizing bacteria (NOB) were more sensitive to changes in salinity than AOMs. Metagenomic analysis revealed that nitrifiers were detected at high level, with the AOB Nitrosomonas sp. comprising 24.9 % and the NOB Nitrospira sp. comprising 47.2% of all nitrifiers. The main functional genes involved in the nitrification reaction were amoABC, hao, and nxrAB. This study demonstrates that higher abundance of functional microorganisms and genes is related to the ammonia-oxidizing activity and ammonia removal contribution rate.}, }
@article {pmid39964491, year = {2025}, author = {Ranaldi, R and Rugnini, L and Migliore, G and Tasso, F and Gabriele, F and Spreti, N and Scuderi, F and Braglia, R and Di Martino, P and Pujia, A and Canini, A}, title = {The role of essential oils as eco-friendly strategy to control biofilm collected in the Colosseum (Rome, Italy).}, journal = {Applied microbiology and biotechnology}, volume = {109}, number = {1}, pages = {48}, pmid = {39964491}, issn = {1432-0614}, mesh = {*Oils, Volatile/pharmacology ; *Biofilms/drug effects/growth &amp; development ; *Thymus Plant/chemistry ; *Origanum/chemistry ; *Lavandula/chemistry ; Italy ; *Disinfectants/pharmacology ; Bacteria/drug effects ; Ocimum basilicum/chemistry/microbiology ; Fungi/drug effects/physiology ; Melaleuca/chemistry ; Cinnamomum/chemistry ; Plant Oils/pharmacology ; Microbial Sensitivity Tests ; }, abstract = {The control of biodeteriogenic microorganisms is essential for the management of heritage sites. Many conventional biocides are no longer available because they have lost their efficacy or have been withdrawn from the market due to their danger to humans and the environment. Therefore, new effective and sustainable biocides are needed, such as plant extracts that could be a good alternative. In this study, essential oils (EOs) of Ocimum basilicum L., Cinnamomum verum Presl, Lavandula angustifolia Mill., Origanum vulgare L., Thymus vulgaris L. and Melaleuca alternifolia Maiden &amp; Betche were tested as green biocides against microorganisms collected from biofilms in the hypogeum of the Colosseum (Rome, Italy). Biocidal screening was first carried out on phototrophic microorganisms grown on BG11 agar culture medium. The efficacy was assessed by measuring photosynthetic activity with a mini-PAM portable fluorometer, and by determining morphological changes or the absence of autofluorescence using light microscopy and confocal laser scanning microscopy. The most effective EOs against phototrophs were further tested to inhibit the growth of heterotrophic fungi and bacteria in order to identify those with a broad-spectrum action. The EOs of cinnamon, oregano and thyme at 5% concentration (v/v) were the most effective against the microorganisms isolated from the biofilms in the Colosseum. These EOs represent a green alternative to traditional chemical biocides due to their activity against a wide range of microorganisms and their complex composition which suggests the potential to reduce the risk of microbial resistance. KEY POINTS: Biofilms collected from the Colosseum hypogeum were characterized EOs tested as biocides against phototrophs and heterotrophs in Colosseum biofilms. Cinnamon, oregano, and thyme EOs show broad-spectrum action at 5% concentration.}, }
@article {pmid39963351, year = {2025}, author = {Nisar, M and Rahman, H and Ahmad, S and Tabassum, T and Alzahrani, KJ and Alzahrani, FM and Alsharif, KF}, title = {Staphylococcus epidermidis: Antimicrobial Resistance Profiles of Biofilm-Forming Isolates From Pediatric Bacteremia in Pakistan.}, journal = {Journal of tropical medicine}, volume = {2025}, number = {}, pages = {8755082}, pmid = {39963351}, issn = {1687-9686}, abstract = {Background: Staphylococcus epidermidis is an important cause of nosocomial infections in children. The study undertaken identified antibiotic resistance markers among biofilm-forming S. epidermidis. Methods: A total of 105 bacteremia-positive samples from hospitalized children were processed for identification of S. epidermidis using species-specific rdr gene. Phenotypic antibiotic resistance was checked through Kirby-Bauer disc diffusion method. 96-well microtiter plate assays and PCR were used for biofilm production and antibiotic-resistant genes, respectively. Results: Among 105 clinical isolates, rdr gene was detected in 34 (32.38%) isolates. The rdr detected isolates exhibited biofilm formation (n = 34; 100%). Multidrug-resistant (MDR) pattern was observed among S. epidermidis, while the frequency of MDR was higher in very strong biofilm-forming S. epidermidis (n = 18; 52.9%, p ≤ 0.002) as compared to weak biofilm-forming S. epidermidis (n = 6; 17.6%). All S. epidermidis strains were resistant to cefoxitin, penicillin, and augmentin (n = 34; 100%). High resistance was observed against erythromycin (n = 29; 85.29%) and ciprofloxacin (n = 25; 73.5%). S. epidermidis displayed complete susceptibility (n = 34; 100%) toward vancomycin, tetracycline, and linezolid. Among the S. epidermidis isolates, the methicillin resistance gene (mecA, n = 29; 85.2%, p ≤ 0.000), the erythromycin resistance gene (msrA, n = 19; 55.7%) and the beta-lactamase resistance gene (blaZ, n = 17; 50%) were detected. Detection of mecA (n = 17; 94.4%), msrA (n = 8; 44.4%) and blaZ (n = 11; 61.1%) significantly (p ≤ 0.0052) correlated with very strong biofilm-forming S. epidermidis. Conclusion: Biofilm formation is significantly associated with antibiotic resistance. The study's result will help to understand the molecular mechanism of antimicrobial resistance in biofilm-forming S. epidermidis among pediatric patients.}, }
@article {pmid39962543, year = {2025}, author = {Charen, C and Waturangi, DE}, title = {Assessment of antibiofilm and quorum quenching potencies of environmental bacteria in controlling biofilm of food spoilage bacteria.}, journal = {BMC research notes}, volume = {18}, number = {1}, pages = {71}, pmid = {39962543}, issn = {1756-0500}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Quorum Sensing/drug effects ; *Food Microbiology ; *Bacillus cereus/drug effects/physiology ; Bacillus subtilis/drug effects/physiology ; RNA, Ribosomal, 16S/genetics ; Chromobacterium/drug effects/physiology ; Bacteria/drug effects/isolation &amp; purification ; Shewanella putrefaciens/drug effects/physiology ; }, abstract = {OBJECTIVES: This research aims to investigate anti-quorum sensing and antibiofilm activity of supernatants from environmental bacteria against the biofilm formed by food spoilage bacteria such as Bacillus cereus, Bacillus subtilis, and Shewanella putrefaciens.<br><br>RESULTS: Supernatants were generated from ten environmental bacteria isolates (A19, A30, A32, A40, B10, B212, C1, J70, J73, and T152), with four isolates (A19, A32, A40, B212) showed anti-quorum sensing activity against Chromobacterium violaceum wild type as indicator bacteria. In inhibition and destruction assays, the highest percentage inhibition of 81.42% and 81.33% by B10 and B212, respectively, against B. cereus and J73 against B. subtilis was recorded at 87.45%. While A32, T152, and C1 performed the highest destruction against B. cereus, B. subtilis, and S. putrefaciens with percentages of 45.4%, 83.81%, 74.81%, respectively. Observation using light microscopy and Scanning Electron Microscopy (SEM) revealed C, O, Na, Mg, Al, Si, K, and Ca elements were detected which might play role in biofilm formation. Based on 16s rRNA sequencing, the environmental bacteria isolates were identified as Enterobacter, Acinetobacter, Acinetobacter, Pantoea genera, C1, and T152. These results imply that these bacteria have destructing and inhibiting potential against Bacillus cereus, Bacillus subtillis, Shewanella putrefaciens.}, }
@article {pmid39960612, year = {2025}, author = {Ferreira, DG and Negri, M}, title = {In vivo and in vitro pathogenicity of Fusarium oxysporum and its biofilm components.}, journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]}, volume = {}, number = {}, pages = {}, pmid = {39960612}, issn = {1678-4405}, support = {001//Coordena&#xe7;&#xe3;o de Aperfei&#xe7;oamento de Pessoal de N&#xed;vel Superior/ ; 307777/2023-5//Conselho Nacional de Desenvolvimento Cient&#xed;fico e Tecnol&#xf3;gico/ ; }, abstract = {Fusarium oxysporum is a widely distributed phytopathogen that affects agricultural crops and has demonstrated relevance in human and veterinary medicine. The virulence of this fungus involves factors such as mycotoxins, immunomodulatory proteins, and the ability to form biofilm. We assessed the pathogenicity of F. oxysporum in its planktonic form, as well as the influence of the extracellular matrix (ECM) from its biofilm on T. molitor larvae and cell culture. F. oxysporum inoculum was injected into larvae at different concentrations, and the survival curve was observed over 10 days. To evaluate the effects of ECM components, biofilms of 24, 72, 96, and 168 h of maturation were used. After extracting the ECM from these biofilms, it was injected into the larvae to assess the hosts response. For the cytotoxicity test of the ECM, were used on Vero cells. The increase in fungal inoculum concentrations was directly proportional to the larval mortality rate. When larvae were infected with the ECM, there was a 40% mortality rate and signs of weakness in the surviving larvae. Furthermore, biofilm metabolites showed cytotoxic effects, with reductions in cellular activity ranging from 20 to 49%. This alternative host model proved effective in investigating the fungal pathogenicity. Additionally, ECM components negatively affected cell viability, suggesting their importance in the damage caused by the fungus in host tissues. This study provides insights for the first time into F. oxysporum virulence and highlights the importance of considering the biofilm ECM in the context of fungal infections.}, }
@article {pmid39959017, year = {2024}, author = {Subiksha, K and Jena, A and Sarangi, P and Mohanty, S and Sahoo, S and Mallick, RR}, title = {Comparative evaluation of antibacterial efficacy of N-acetylcysteine, Aegle marmelos, and chitosan as intracanal medicaments against Enterococcus faecalis biofilm - An in vitro study.}, journal = {Journal of conservative dentistry and endodontics}, volume = {27}, number = {12}, pages = {1246-1250}, pmid = {39959017}, issn = {2950-4708}, abstract = {CONTEXT: The main objective of root canal treatment is the removal of bacteria. Established medicaments and their combinations have been compromised in efficacy against Enterococcus faecalis, causing the need to explore novel intracanal medicaments.<br><br>AIM: The aim of the study was to evaluate the antibacterial efficacy of chitosan, N-acetylcysteine (NAC), and Aegle marmelos as intracanal medicaments against E. faecalis biofilm.<br><br>MATERIALS AND METHODOLOGY: Minimum inhibitory concentration and susceptibility of medicaments determined. Two hundred and forty dentin disc specimens were prepared and inoculated with E. faecalis for 21 days. Samples were divided into four groups (A - N-acetylcysteine; B - Aegle marmelos; C - Chitosan; D -Control) (n = 60), and two subgroups (n = 30) based on the duration of medicament placed (subgroup 1: 24 h, subgroup 2: 7 days). Thereafter, dentinal shavings were retrieved, incubated in agar plate, visible colonies counted, and statistically analyzed.<br><br>RESULTS: At 24 h Group C1 exhibited the lowest CFUs, followed by Group A1, Group B, and Group D1. On the 7[th] day, Group B2 showed the lowest CFUs, followed by Group A2, Group C2, and Group D2.<br><br>CONCLUSIONS: Against E. faecalis, NAC has the highest antimicrobial properties closely followed by Aegle marmelos and both provide promising novel possibilities for use as intracanal medicaments.}, }
@article {pmid39958935, year = {2025}, author = {Wei, M and Wang, P and Li, T and Liu, J and Wang, Y and Gu, L and Wang, S}, title = {Transcriptome analysis reveals the molecular mechanism of γ-linolenic acid eradicating the biofilm of vancomycin-resistant Enterococcus faecium.}, journal = {Frontiers in cellular and infection microbiology}, volume = {15}, number = {}, pages = {1525581}, pmid = {39958935}, issn = {2235-2988}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Gene Expression Profiling ; *Enterococcus faecium/drug effects/genetics/metabolism ; *Gene Expression Regulation, Bacterial/drug effects ; *Anti-Bacterial Agents/pharmacology ; *gamma-Linolenic Acid/pharmacology ; *Vancomycin-Resistant Enterococci/drug effects/genetics ; Enterococcus faecalis/drug effects/genetics/metabolism ; Bacterial Proteins/genetics/metabolism ; Humans ; Transcriptome ; Microbial Sensitivity Tests ; }, abstract = {INTRODUCTION: Vancomycin-resistant Enterococcus faecium (VRE-fm) biofilms pose a significant clinical challenge due to the limited effectiveness of traditional antibiotics. This study investigates the potential of γ-linolenic acid (GLA) as a novel antibiofilm agent.<br><br>METHODS: Transcriptome analysis was performed on the V27 isolate, comparing cells in mature biofilms treated with and without GLA. The findings were further validated using qRT-PCR on six VRE-fm isolates and two E. faecalis isolates.<br><br>RESULTS: Transcriptome analysis revealed a significant downregulation in the expression levels of genes associated with biofilm formation, including fruA, fruB, sgrA, lpxtg-cwa, tfpp, lafA, lafB, malP, fsrA, and fsrC', while a significant upregulation was observed in the expression of fsrBD. Validation by qRT-PCR in six VRE-fm isolates confirmed the significant changes in the expression levels of all genes except for lpxtg-cwa, with statistical significance. The expression of bgsB and bgsA genes, which are the homologs of lafA and lafB genes, along with the Fsr-regulated genes gelE and sprE in E. faecalis, were also found to be downregulated by GLA. In addition, KEGG analysis identified specific metabolic pathways that were significantly downregulated by GLA.<br><br>CONCLUSION: GLA effectively targets multiple aspects of biofilm formation in VRE-fm, including the downregulation of key biofilm-related genes, the inhibition of quorum sensing systems, and the modulation of metabolic pathways. GLA emerges as a promising candidate for eradicating Enterococcus biofilms.}, }
@article {pmid39958634, year = {2024}, author = {Mahendrarajan, V and Lazarus, H and Easwaran, N}, title = {Corrigendum to "Quorum quenching mediated biofilm impediment in Chromobacterium violaceum and Staphylococcus aureus by leaf extracts of Delonix elata".}, journal = {Heliyon}, volume = {10}, number = {17}, pages = {e35542}, doi = {10.1016/j.heliyon.2024.e35542}, pmid = {39958634}, issn = {2405-8440}, abstract = {[This corrects the article DOI: 10.1016/j.heliyon.2024.e31898.].}, }
@article {pmid39958633, year = {2024}, author = {Haque, MM and Bari Rupok, MR and Molla, AH and Rahman, MM and Shozib, HB and Mosharaf, MK}, title = {Corrigendum to "Rhizoengineering with biofilm producing rhizobacteria ameliorates oxidative stress and enhances bioactive compounds in tomato under nitrogen-deficient field conditions" [Heliyon Volume 10, Issue 14, July 2024, Article e34276].}, journal = {Heliyon}, volume = {10}, number = {17}, pages = {e36346}, doi = {10.1016/j.heliyon.2024.e36346}, pmid = {39958633}, issn = {2405-8440}, abstract = {[This corrects the article DOI: 10.1016/j.heliyon.2024.e34276.].}, }
@article {pmid39958232, year = {2025}, author = {Wang, Y and Li, Z and Ji, L and Sun, J and Gao, F and Yu, R and Li, K and Wang, W and Zhao, W and Zhong, QZ and Ge, S and Li, J}, title = {Adhesive micro-liquid for efficient removal of bacterial biofilm infection.}, journal = {Materials today. Bio}, volume = {31}, number = {}, pages = {101525}, pmid = {39958232}, issn = {2590-0064}, abstract = {Bacteria are common infectious pathogens that can cause invasive and potentially life-threatening infections. Ionic liquids have emerged as a novel class of alternatives to antibiotics, however their inherent hydrophobicity and immiscible in water exhibits poor adhesion to bacteria and diminishes its utilization and bioavailability for infection control. Herein, an adhesive metal phenolic encapsulated ionic liquid choline and geranate (CAGE@MPN) microcapsules is designed to address the aforementioned challenges and remove bacterial biofilm infections. The CAGE@MPN microcapsules are prepared through self-assembly of quercetin and ferrous ions on the interface of CAGE and water via metal-phenolic coordination. The MPN interface can stabilize the micro liquid and effectively adhere to bacterial surfaces. The microcapsules can disrupt bacterial cell walls to facilitate the release of cellular contents and destruct the biofilm, thereby exerting a pronounced bactericidal effect. The in vivo bactericidal effect of CAGE@MPN microcapsules is demonstrated in a murine model of Staphylococcus aureus (S. aureus) skin infection. The proposed adhesive micro-liquid system offers a promising strategy for noninvasive and efficient removal of bacterial biofilm infection.}, }
@article {pmid39957834, year = {2025}, author = {Silva, AR and Keevil, CW and Pereira, A}, title = {Legionella pneumophila response to shifts in biofilm structure mediated by hydrodynamics.}, journal = {Biofilm}, volume = {9}, number = {}, pages = {100258}, pmid = {39957834}, issn = {2590-2075}, abstract = {Preventing legionellosis in water systems demands effective hydrodynamic management and biofilm mitigation. This study investigates the complex relationship between hydrodynamics (80 RPM and stagnation), biofilm mesoscale structure and Legionella pneumophila colonization, by addressing three key questions: (1) How do low flow vs stagnation conditions affect biofilm response to L. pneumophila colonization?, (2) How do biofilm structural variations mediate L. pneumophila migration across the biofilm?, and (3) Can specific hydrodynamic conditions trigger L. pneumophila entrance in a viable but nonculturable (VBNC) state? It was found that Pseudomonas fluorescens biofilms exhibit different responses to L. pneumophila based on the prevailing hydrodynamic conditions. While biofilm thickness and porosity decreased under shear (80 RPM), thickness tends to significantly increase when pre-established 80 RPM-grown biofilms are set to stagnation upon L. pneumophila spiking. Imposing stagnation after the spiking also seemed to accelerate Legionella migration towards the bottom of the biofilm. Water structures in the biofilm seem to be key to Legionella migration across the biofilm. Finally, shear conditions favoured the transition of L. pneumophila to VBNC states (∼94 %), despite the high viable cell counts (∼8 log10 CFU/cm[2]) found throughout the experiments. This research highlights the increased risk posed by biofilms and stagnation, emphasizing the importance of understanding the mechanisms that govern Legionella behaviour in diverse biofilm environments. These insights are crucial for developing more effective monitoring and prevention strategies in water systems.}, }
@article {pmid39955677, year = {2025}, author = {Adhikary, R and Maiti, PK and Ghosh, N and Rajbanshi, B and Roy, MN and Mandal, S and Mandal, V}, title = {Lipopeptide iturin C3 from endophytic Bacillus sp. effectively inhibits biofilm formation and prevents the adhesion of topical and food-borne pathogens in vitro and on biomedical devices.}, journal = {Archives of microbiology}, volume = {207}, number = {3}, pages = {62}, pmid = {39955677}, issn = {1432-072X}, support = {Memo no. 285(Sanc.)/ST/P/S&amp;T/2G-10/2017, Dated 28.03.2018//Department of Science and Technology and Biotechnology, Govt of West Bengal/ ; Memo no. 285(Sanc.)/ST/P/S&amp;T/2G-10/2017, Dated 28.03.2018//Department of Science and Technology and Biotechnology, Govt of West Bengal/ ; DST-SERB/F/5369/2013-'14; dated 19.11.2013//Department of Science and Technology, Science and Engineering Board, Government of India/ ; }, mesh = {*Biofilms/drug effects ; *Bacillus/chemistry/physiology/drug effects ; Humans ; *Bacterial Adhesion/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; Microbial Sensitivity Tests ; Peptides, Cyclic/pharmacology/chemistry ; Lipopeptides/pharmacology/chemistry ; Surface-Active Agents/pharmacology/chemistry ; Endophytes/chemistry/physiology/metabolism ; Cell Line ; Bacteria/drug effects ; }, abstract = {Iturin, a structurally cyclic heptapeptides with a number of homologous derivatives has broad-spectrum antimicrobial and antibiofilm properties. The present study elucidates the structure and antimicrobial efficacy of iturin C3 biosurfactant (BS) produced by the endophytic bacterium Bacillus sp. LLB-04. Bacillus sp. LLB-04 was isolated from the leaves of hemiparasite Scurrula parasitica L. during the winter season. The biosurfactant was produced in a static batch culture of 120 h using Nutrient Broth (NB) medium and was extracted by a series of solvent systems. The BS was purified by solvent fractionation and preparative High-Performance Liquid Chromatography (HPLC) method, and then it was structurally characterized through various analytical methods. Its antimicrobial and antibiofilm activities were tested against 0, to 18 h old topical and food-borne pathogens. Furthermore, the cellular aggregation and bacterial cell adhesion on polystyrene and urethral catheters were checked at the Biofilm inhibitory concentration (BIC). The cell line toxicity of BS (0-1.568 mg/ml) was tested against the human embryonic lung tissue L-132 and human alveolar epithelial cancer cell line, and the in silico mode of action was studied using standard methods. From the spectroscopic studies of 96 h culture harvested BS revealed that Bacillus sp. LLB-04 (GenBank Accession No.: MF037706) produced the BS as iturin C3. The BS had broad-spectrum antimicrobial with minimum inhibitory concentration (MIC) values ranging from 0.1 to 1.6 mg/ml and an average biofilm inhibition concentration (BIC) of 0.8-1.6 mg/ml in 18 h old cells where biofilm formation was inhibited up to 46.4 times at 1.6 mg/ml concentration. It could also destabilize 40-48 h old preformed biofilm and had a synergistic response with streptomycin (Bacillus subtilis MTCC 411, Escherichia coli MTCC 730), ciprofloxacin (B. subtilis MTCC 411, E. coli MTCC 730), and vancomycin (Staphylococcus epidermidis MTCC 3086, B. subtilis MTCC 411). It had antiproliferative activity (0.1-0.8 mg/ml) on cancer cell lines. In-silico protein-ligand interactions predicted that it could interact with different membrane proteins of topical and food-borne pathogens. Thus, the study revealed for the first time that the endophytic Bacillus sp. could be exploited for large-scale production of iturin C3 that could be used in combating biofilm formation and cellular adhesion of topical and food-borne pathogens.}, }
@article {pmid39954737, year = {2025}, author = {Locke, SR and Vinayamohan, PG and Diaz-Campos, D and Habing, G}, title = {Biofilm forming abilities of Salmonella serovars isolated from clinically ill livestock at 48 and 168 hours.}, journal = {Journal of food protection}, volume = {}, number = {}, pages = {100466}, doi = {10.1016/j.jfp.2025.100466}, pmid = {39954737}, issn = {1944-9097}, abstract = {Little is known regarding the biofilm forming capabilities of a somewhat distinct population of Salmonellae present on-farm and responsible for illnesses in livestock and humans. Evaluation of cleaning and disinfection in preharvest environments has found little success in eradicating Salmonella biofilms to date. Disrupting environmental survival of Salmonella via biofilm removal will be critical to reducing carriage in livestock reservoirs and the risk of foodborne illness. Therefore, the objective of this study was to characterize the biofilm forming abilities of Salmonellae relevant to livestock and human health. Eighty-one isolates from 8 serovars (S. Typhimurium, Heidelberg, Montevideo, Agona, Newport, Dublin, 4,[5],12:i:-, Enteritidis) were sourced from poultry and clinically ill cattle, swine, and equine. We hypothesized that biofilm production rate would vary significantly between serovars, and biofilm density would increase from 48 to 168 hrs. Isolates were grown in 24-well microplates in tryptone soy broth at ambient temperature, with media refreshed every 48 hours. Biofilm density was quantified using crystal violet assays. Strong biofilm formers comprised 84% (68/81) of isolates tested, while 5.9% (4/81) were considered weak. Biofilm density was significantly greater at 168 hours versus 48 hours for all serovars except Dublin. Additionally, biofilm growth rate varied by serovar. Differences in biofilm-associated genes were evaluated, and only detection of csrB was significantly associated with categorization of biofilm producers. Results suggest inconsistent cleaning likely allows for the establishment of biofilms in on-farm environments. Further, some serovars may pose a greater risk for rapid biofilm establishment. This study provides data necessary to inform the development of evidence-based cleaning and disinfection protocols effective against the most prolific biofilm forming strains of virulent Salmonella.}, }
@article {pmid39954522, year = {2025}, author = {Yavarinasab, A and He, J and Mookherjee, A and Krishnan, N and Pestana, LR and Fusco, D and Bizzotto, D and Tropini, C}, title = {Electrogenic dynamics of biofilm formation: Correlation between genetic expression and electrochemical activity in Bacillus subtilis.}, journal = {Biosensors &amp; bioelectronics}, volume = {276}, number = {}, pages = {117218}, doi = {10.1016/j.bios.2025.117218}, pmid = {39954522}, issn = {1873-4235}, abstract = {Biofilms are structured microbial communities, known for their electron transfer properties, which are essential for metabolic processes and microbial survival. Here, we investigated the electrogenic properties of Bacillus subtilis, a bacterial producer of electron-donating biofilms. Interdigitated gold electrodes were utilized to continuously measure the electrochemical activity of biofilm-forming B. subtilis cells and genetic mutants unable to create them (biofilm-deficient). The formation of extracellular polymeric substances (EPS) and filamentous appendages was monitored via scanning electron microscopy (SEM). Chronoamperometry was used to assess electrochemical activity, which showed fluctuations in electrical current at specific time points in biofilm-forming cells. Cyclic voltammetry (CV) revealed significant differences between the voltammograms of biofilm-forming and biofilm-deficient cells, hypothesized to be a result of the reduction of secreted flavodoxin. Electrochemical impedance spectroscopy (EIS) was also performed at various intervals and analyzed using an equivalent circuit. We identified the presence of a charge transfer resistance (Rct) exclusively in biofilm which correlated to the time of increased electrochemical activity measured using chronoamperometry. Finally, through confocal microscopy, we found that the expression of a gene involved in biofilm matrix formation, tasA, was correlated with the time when charge transfer was measured. These results indicate that electrochemical activity is primarily present in biofilm-forming cells rather than in biofilm-deficient mutants. By combining electrochemical and microscopic methods, we developed a methodology to continuously monitor the stages of biofilm formation and showed that electrochemical activities within biofilms vary over time and there is a temporal relationship between these processes and the expression of genes responsible for biofilm development.}, }
@article {pmid39954282, year = {2025}, author = {Sobrinho, BP and Silva, BP and Andrade, KM and Sobrinho, BP and Ribeiro, DA and Santos, JN and Oliveira, LR and Cury, PR}, title = {Intelligent biofilm detection with ensemble of deep learning networks.}, journal = {Medicina oral, patologia oral y cirugia bucal}, volume = {}, number = {}, pages = {}, doi = {10.4317/medoral.26937}, pmid = {39954282}, issn = {1698-6946}, abstract = {BACKGROUND: Dental biofilm is traditionally identified visually, which can be challenging and time-consuming due to its color similarity with the tooth. The aim of this study was to evaluate the performance of U-Net neural networks for the automatic detection of dental biofilm without disclosing agents on intraoral photographs of deciduous and permanent teeth using an ensemble strategy.<br><br>MATERIAL AND METHODS: This retrospective exploratory study was conducted on two datasets of intraoral images obtained from deciduous and permanent dentitions. The first dataset was used to validate dental biofilm annotations by an expert with disclosing agents. The second dataset, without disclosing agents, was employed to train and evaluate the U-Net neural network in the identification of dental biofilms using an ensemble strategy.<br><br>RESULTS: The performance of the ensemble method was assessed using a cross-validation procedure, with six groups dedicated to training, one group for validation, and one group exclusively taken as a test set for the final evaluation of the ensemble. The performance of the neural network was evaluated using accuracy, F1 score, sensitivity, and specificity. The U-Net neural network achieved an accuracy of 93.1%, sensitivity of 65.1%, specificity of 95.9%, and an F1 score of 63.0%.<br><br>CONCLUSIONS: The U-Net neural network using the ensemble strategy was able to automatically identify visually detectable dental biofilms on intraoral photographs. The application of this new knowledge will soon be available in clinical practice.}, }
@article {pmid39953285, year = {2025}, author = {Krishnakumar, KA and Remya Babu, R and Sugathan, S and Lankalapalli, RS}, title = {KRN7000 analogues as biofilm disrupting agents against Streptococcus pyogenes and Proteus mirabilis.}, journal = {The Journal of antibiotics}, volume = {}, number = {}, pages = {}, pmid = {39953285}, issn = {1881-1469}, support = {VIR/17/2020/ECD-I//Indian Council of Medical Research (ICMR)/ ; }, abstract = {In this study, three KRN7000 analogues with variations in the sugar and glycosidic linkage were synthesised to assess their efficacy in disrupting the biofilms of S. pyogenes and P. mirabilis. All three analogues exhibited antibacterial activity, with the effects being more prominent at lower concentrations in S. pyogenes. The N-alkylated, 1-deoxy analogue emerged as the most effective, significantly reducing biofilm formation and extracellular polymeric substances (EPS) in both organisms. Microscopic analysis revealed notable disruption of biofilm structure by the analogue, resulting in a significant reduction in EPS for both organisms and decreasing cell surface hydrophobicity. These results position the KRN7000 analogue as a promising candidate for developing glycolipid-based antibiofilm agents.}, }
@article {pmid39952768, year = {2025}, author = {Yang, Y and Yan, X and Redding, M and Gu, G and Luo, Y and Patel, J and Nou, X}, title = {Biofilm formation of Escherichia coli O157:H7 strains associated with recent reoccurring lettuce outbreaks.}, journal = {Food microbiology}, volume = {128}, number = {}, pages = {104728}, doi = {10.1016/j.fm.2025.104728}, pmid = {39952768}, issn = {1095-9998}, mesh = {*Escherichia coli O157/physiology/drug effects/genetics/growth &amp; development ; *Biofilms/growth &amp; development ; *Lactuca/microbiology ; *Disease Outbreaks ; Humans ; Escherichia coli Infections/microbiology/epidemiology ; Quaternary Ammonium Compounds/pharmacology ; Anti-Bacterial Agents/pharmacology ; Food Microbiology ; Foodborne Diseases/microbiology/epidemiology ; }, abstract = {Genomically closely clustered E. coli O157:H7 strains have been implicated in several recent multistate outbreaks linked to romaine lettuce. The underlying factors contributing to their reoccurrence and persistence remain elusive. Biofilm formation and acid resistance are crucial factors for foodborne pathogens in their environmental persistence and success in host gastrointestinal invasion. Thus, the objective of this study was to investigate the biofilm-forming capability of outbreak strains, their resistance to antimicrobials, and their tolerance to gastric acid, by comparing O157:H7 strains associated with recent reoccurring outbreaks and those associated with previous lettuce, spinach, and hamburger outbreaks. The recent outbreak strains, which were collectively described as "reoccurring, emerging, and persistent (REP)", exhibited significantly stronger biofilm-forming capabilities and resistance to quaternary ammonium compounds (QACs) compared to other strains. They also exhibited strong tolerance to simulated gastric fluid. Their ability to form robust biofilms is likely attributed to their pronounced production of curli and cellulose, as demonstrated on Congo Red and Calcoflour White agar plates. Moreover, their exceptional resistance to sanitizers may stem from the formation of dense biofilms with higher cellulose content, as visualized using fluorescent dyes under confocal laser scanning microscopy. The findings of this study support the assertion that biofilm formation is a critical factor for the reoccurring outbreak strains for environmental persistence and provide insights for developing prevention strategies.}, }
@article {pmid39952760, year = {2025}, author = {Liu, Y and Ge, W and Sun, Y and Dai, H and Fan, L and Yuan, L and Yang, Z and Jiao, X}, title = {Unraveling the ecological interactions between dairy strains Bacillus licheniformis and Bacillus cereus during the dual-species biofilm formation.}, journal = {Food microbiology}, volume = {128}, number = {}, pages = {104716}, doi = {10.1016/j.fm.2024.104716}, pmid = {39952760}, issn = {1095-9998}, mesh = {*Bacillus cereus/genetics/physiology/growth &amp; development/metabolism ; *Biofilms/growth &amp; development ; *Bacillus licheniformis/genetics/metabolism/physiology/growth &amp; development ; Dairy Products/microbiology ; Microbial Interactions ; Food Microbiology ; Bacterial Proteins/genetics/metabolism ; }, abstract = {Bacillus cereus and Bacillus licheniformis are widely presented in dairy products. They can form thick biofilms on surfaces of dairy processing equipment, which may pose serious safety issues and spoilage of final dairy products. However, how ecological interactions between B. cereus and B. licheniformis affect the functions and stability of mixed-species biofilm remains uncovered. In this work, the altered profiles of a dual-species biofilm by dairy-derived B. cereus 121 and B. licheniformis 919 were investigated by RNA-sequencing analysis in combined with phenotype validation (bacterial growth, biofilm-forming capacity, biofilm EPS production, and biofilm structures). The results confirmed that the presence of B. cereus 121 reduced the growth of B. licheniformis 919 planktonic cells, and decreased the biofilm cell numbers of B. licheniformis 919 in the dual-species biofilm when compared to that in its single-species biofilm. The bacterial interaction also reduced the amount of proteins and carbohydrates in the biofilm matrix, and decreased the coverage, average thickness, and total biomass of biofilms. In addition, results from RNA-sequencing analysis showed that the bacterial interaction caused a total of 128 (B. licheniformis 919) and 216 (B. cereus 121) differentially expressed genes (DEGs) during the co-culture of planktonic cells. Functional annotation revealed that the DEGs of B. licheniformis 919 were mainly involved in 10 downregulated pathways including citrate cycle, pyruvate metabolism, nonribosomal peptide structures, glycolysis/gluconeogenesis, quorum sensing, alanine, aspartate and glutamate metabolism, oxidative phosphorylation, beta-Lactam resistance, arginine and proline metabolism, and beta-Alanine metabolism when co-cultured with B. cereus 121. On the other hand, the DEGs from B. cereus 121 were significantly enriched for two downregulated pathways (cysteine and methionine metabolism, and inositol phosphate metabolism) and four upregulated pathways (nitrogen metabolism, glyoxylate and dicarboxylate metabolism, glycine, serine and threonine metabolism, and propanoate metabolism). Results of this study facilitate updated knowledge of how bacterial interaction during the biofilm formation shapes the features of the mixed-species biofilm.}, }
@article {pmid39951665, year = {2025}, author = {Zeybek Sivas, Z and Yıldırım, N}, title = {The Possible Role of Biofilm Formation in Recidivism of Cholesteatomatous and Noncholesteatomatous Chronic Suppurative Otitis Media.}, journal = {Otology &amp; neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology}, volume = {46}, number = {3}, pages = {e74-e80}, doi = {10.1097/MAO.0000000000004424}, pmid = {39951665}, issn = {1537-4505}, mesh = {Humans ; *Biofilms/growth &amp; development ; *Otitis Media, Suppurative/microbiology/surgery ; Male ; Female ; Adult ; Middle Aged ; Chronic Disease ; *Staphylococcus aureus/physiology ; Pseudomonas aeruginosa/physiology ; Cholesteatoma, Middle Ear/surgery/microbiology ; Aged ; Young Adult ; Recurrence ; Adolescent ; Klebsiella pneumoniae ; }, abstract = {OBJECTIVE: Chronic suppurative otitis media (CSOM) is typically classified into two distinct types: CSOM (without cholestetoma) and CSOM with cholesteatoma (CCSOM). The main microbial agents in both types are Pseudomonas aeruginosa, Staphylococcus aureus, and Klebsiella pneumoniae. It is believed that the virulence of the infecting microorganisms and their biofilm production capacity play a role in the chronicity and persistence of the disease. The aim of this study was to investigate the pathogen microorganisms with their biofilm formation in CSOM, CCSOM, and their recidivism.<br><br>MATERIALS AND METHODS: A cohort of 57 patients was separated into four subgroups as primary CSOM (CSOM, CCSOM) and postoperatively recurring/residual CSOM [(R)CSOM, (R)CCSOM] groups. A control group was formed of 10 patients who underwent tympanotomy for conductive hearing loss without any known past/present ear inflammation. In all 67 patients, ear swabs for culture and the tissue samples for biofilm studies were obtained pre- or intraoperatively.<br><br>RESULTS: The most common bacteria grown in the culture mediums were Pseudomonas spp., S. aureus, coagulase-negative Staphylococcus, and coliform bacteria. In the SEM study, biofilms were detected in 9 of 15 CCSOM and 6 of 14 CSOM, and in 13 of 14 (R)CCSOM and 11 of 14 (R)CSOM ears. Statistical analysis showed significantly higher rates of biofilm formation in both recidivist cholesteatomatous and noncholesteatomatous CSOM groups than their primary counterpart groups.<br><br>CONCLUSION: The findings that biofilm is more prevalent in the recidivist cases substantiated that biofilm formation is correlated with the persistence and additionally aggressiveness of the disease in both CSOM types. S. aureus appeared as the leading biofilm-producing bacterium.}, }
@article {pmid39951131, year = {2025}, author = {George, T and Sivam, V and Vaiyapuri, M and Anandan, R and Sivaraman, GK and Joseph, TC}, title = {Standardizing biofilm quantification: harmonizing crystal violet absorbance measurements through extinction coefficient ratio adjustment.}, journal = {Archives of microbiology}, volume = {207}, number = {3}, pages = {59}, pmid = {39951131}, issn = {1432-072X}, mesh = {*Biofilms/growth &amp; development ; *Gentian Violet/chemistry ; *Staphylococcus aureus/physiology/drug effects ; *Escherichia coli/physiology/drug effects ; Ethanol/pharmacology ; Acetic Acid/chemistry/pharmacology ; }, abstract = {Precise quantification of biofilm is critical as the formation and persistence of biofilm have significant implications in the environmental, therapeutic and industrial contexts. The microtiter plate assay using crystal violet with 33% glacial acetic acid or 94-100% ethanol as the resolubilising agent is widely used for the categorisation of biofilms into weak, moderate and strong categories. But, the use of varying wavelengths for the measurement of biofilm resulted in discrepancies in categorisation across the studies due to the difference in the extinction coefficient of CV. This study emphasises the importance of measuring the biofilm at the absorbance maximum (λmax) of resolubilized CV, identified as 585 nm for 33% acetic acid and 580 nm for 94-100% ethanol. To address the challenge of harmonizing the results across studies, a method was developed to adjust the biofilm categorisation threshold based on the extinction coefficient ratios of CV at different wavelengths enabling consistent classification regardless of the wavelength used. Validation with E. coli and S. aureus demonstrated that the adjusted thresholds produced results similar to that obtained with the λmax. This standardised approach not only enables the researchers to obtain accurate and consistent results in the future studies, but also facilitates the comparison of previously published data on biofilm research, which is essential for the exploration of newer therapeutic strategies against biofilm related infections.}, }
@article {pmid39949693, year = {2024}, author = {Sangeeta, JP and Aishwarya, OB and Omkar, DB and Madhura, NB}, title = {Anti-biofilm effect of clove oil against Candida albicans: A systematic review.}, journal = {Journal of oral and maxillofacial pathology : JOMFP}, volume = {28}, number = {4}, pages = {665-671}, pmid = {39949693}, issn = {0973-029X}, abstract = {In recent years, Candida albicans has emerged as a significant opportunistic pathogen, causing various infections, particularly in immunocompromised geriatric individuals. One of the major hindrances in managing Candida infections lies in its potential to develop and survive in biofilms, which demonstrate resistance to conventional antifungal therapies, thereby complicating treatment strategies. While clove oil has shown promising results as a potential antifungal agent, its specific anti-biofilm effects against Candida albicans biofilms remain relatively underexplored. Therefore, there is a need for a comprehensive review to evaluate the existing literature on the anti-biofilm properties of clove oil and its mechanisms of action against Candida albicans biofilms. Such a review will provide valuable insights into the potential therapeutic applications of clove oil in combating biofilm-associated Candida infections. This review will enable us to infer and understand the potential effects of clove oil against Candida albicans. This systematic review aims to determine the anti-biofilm efficacy of clove oil against Candida albicans. This systematic review was registered in 'PROSPERO' (CRD42024524134) and followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The literature searches used Google Scholar, PubMed, and Science Direct databases. All original studies published in English from 2004 to 2023 were included. From 37 studies found online, only four were reviewed. Results showed that clove oil had significant anti-biofilm activity when assessed against Candida albicans. Our systematic review provides insights into clove oil's potential as a therapeutic agent against Candida albicans biofilms. Clove oil also represents a promising avenue for future research and development in managing Candida biofilms.}, }
@article {pmid39948126, year = {2025}, author = {Sabira, O and Ajaykumar, AP and Varma, SR and Jayaraj, KN and Kotakonda, M and Kumar, P and Vaikkathillam, P and Sivadasan Binitha, V and Alen, AP and Raghu, AV and Zeena, KV}, title = {Nepenthes pitcher fluid for the green synthesis of silver nanoparticles with biofilm inhibition, anticancer and antioxidant properties.}, journal = {Scientific reports}, volume = {15}, number = {1}, pages = {5349}, pmid = {39948126}, issn = {2045-2322}, mesh = {*Metal Nanoparticles/chemistry ; *Silver/chemistry/pharmacology ; *Biofilms/drug effects ; *Antioxidants/pharmacology/chemistry ; *Antineoplastic Agents/pharmacology/chemistry/chemical synthesis ; *Green Chemistry Technology ; *Pseudomonas aeruginosa/drug effects/physiology ; Humans ; Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; Cell Survival/drug effects ; }, abstract = {This is the first report of silver nanoparticles (AgNPs) synthesis utilizing the pitcher secretion from an insectivorous plant, specifically Nepenthes ventrata, through a microwave assisted green synthesis approach. The successful formation of AgNPs was validated through a comprehensive set of analyses, including UV-Vis spectroscopy, Fourier-transform infrared spectroscopy, transmission electron microscopy, DLS analysis and Zeta potential measurements. In addition gas chromatography-high-resolution mass spectrometry and liquid chromatography-high-resolution mass spectrometry analyses were conducted to examine the components present in the pitcher secretion. These analyses aimed to identify the capping and stabilizing agents in the secretion that facilitate the synthesis and stability of AgNPs. The synthesized AgNPs significantly inhibited biofilm formation by Pseudomonas aeruginosa PAO1, as demonstrated by Crystal Violet staining and fluorescence microscopy. Additionally, these AgNPs showed promising antioxidant properties through a DPPH radical scavenging assay. Furthermore, the anticancer properties of the AgNPs were analyzed using an MTT assay, which measures cell metabolic activity as an indicator of cell viability, proliferation, and cytotoxicity. Collectively, these findings suggest that the biosynthesized AgNPs possess multifaceted biological applications, showcasing their utility as both antimicrobial and antioxidative agents, and highlighting their potential in medical and environmental applications.}, }
@article {pmid39947354, year = {2025}, author = {Motaung, TE and Ratsoma, FM and Kunene, S and Santana, QC and Steenkamp, ET and Wingfield, BD}, title = {Harnessing exogenous membrane vesicles for studying Fusarium circinatum and its biofilm communities.}, journal = {Microbial pathogenesis}, volume = {}, number = {}, pages = {107368}, doi = {10.1016/j.micpath.2025.107368}, pmid = {39947354}, issn = {1096-1208}, abstract = {Extracellular vesicles (EVs) are tiny messengers that convey bioactive molecules from donor to recipient cells, leading to changes in their physiology and function. We investigated the role of EVs in shaping growth and the biofilm biology of the tree pathogen Fusarium circinatum and its interaction with the susceptible host, Pinus patula. Vesicles were collected from fungal planktonic and biofilm cultures and from pine seedling needles and roots. The physical properties of these vesicles were analysed using nanoparticle tracking analysis and transmission electron microscopy, which revealed a diverse range of sizes and shapes, respectively. Furthermore, uptake of vesicles by conidia was conducted. The results demonstrated that F. circinatum EVs significantly but variably affected spore viability during the early phase (2-4 h) although they enhanced fungal biofilm integrity. In contrast, P. patula EVs greatly inhibited hyphal formation and biofilm biomass, but failed to inhibit matrix production in the fungal biofilm. Our results therefore show that conidial germination is essential for late fungal development including hyphal and biofilm formation while matrix production is a counter measure against harsh environmental conditions including the effects of plant-derived EVs.}, }
@article {pmid39946969, year = {2025}, author = {Qi, S and Xu, Y and Fan, Z and Chen, S and Zhang, S and Zhang, L and Song, RB and Li, Z}, title = {Integrating MXene with carbon dots modified bacteria as hybrid biofilm for photo-assisted microbial fuel cells.}, journal = {Journal of colloid and interface science}, volume = {687}, number = {}, pages = {65-73}, doi = {10.1016/j.jcis.2025.02.052}, pmid = {39946969}, issn = {1095-7103}, abstract = {The development of microbial fuel cells (MFCs) places a high demand on the building of high-performance exoelctrogenic biofilm. In this study, by the electrostatic self-assemble between Ti3C2Tx MXene and carbon dots-modified exoelctrogenic bacteria (B@CDs), a MXene-based hybrid biofilm has been developed for MFCs. The modification of positively-charged CDs onto bacterial surface not only builds the bridge between negatively-charged MXene and bacterial cells for the construction of hybrid biofilm, but also endows the photoelectric conversion ability for the realization of multiple energy transfer in hybrid biofilm. Meanwhile, the MXene network paves high-speed pathways for electron transfer during microbial catalytic oxidation and photoelectric conversion processes. As a result, the MFC with this MXene-based hybrid biofilm has achieved a maximum power density of 7518.5 mW/m[2] in darkness, which increased to 9396.1 mW/m[2] under light illumination. This work not only offers a good start for the development of MXene-based hybrid biofilm, but also upgrades the performance of photo-assisted microbial fuel cells to a high level for highlighting their application potential as the green and sustainable energy source.}, }
@article {pmid39946758, year = {2025}, author = {Pagotto, LL and Cury, JA and Ricomini-Filho, AP}, title = {Extracellular polysaccharide-rich biofilm reduces chlorhexidine effect on enamel demineralization: An in situ study.}, journal = {Archives of oral biology}, volume = {173}, number = {}, pages = {106187}, doi = {10.1016/j.archoralbio.2025.106187}, pmid = {39946758}, issn = {1879-1506}, abstract = {OBJECTIVES: This study investigated the effect of chlorhexidine (CHX) on demineralization, cell viability and matrix composition in EPS-rich (EPS[+]) and poor (EPS[-]) oral biofilms.<br><br>DESIGN: A split-mouth and crossover in situ study was conducted with six participants over two phases of 14 days each. During a lead-in step, biofilms were formed under either sucrose exposure (EPS[+]) or glucose +&#x202f;fructose exposure (EPS[-]). In the experimental step, participants rinsed with either 0.9&#x202f;% NaCl (negative control) or 0.12&#x202f;% CHX for seven days.<br><br>RESULTS: Data showed that EPS[+] biofilms exhibited higher enamel surface hardness loss (%SHL), lesion area (&#x2206;S) and concentrations of soluble and insoluble EPS, compared to EPS[-] biofilms. After treatments, CHX significantly reduced the counts of colony-forming units (CFU) in both EPS[-] and EPS[+] biofilms. However, CHX only reduced &#x2206;S within the EPS[-] group. There was no significant difference in demineralization change (%&#x2206;S) among treatments. Additionally, CHX decreased soluble and insoluble EPS concentrations in the EPS[+] group.<br><br>CONCLUSION: While CHX effectively reduced bacterial counts, its antimicrobial effect may not be enough to reduce the enamel demineralization caused by mature EPS-rich biofilms.}, }
@article {pmid39944120, year = {2025}, author = {Samanta, P and Ghorai, S}, title = {Prediction of SafD adhesin strong binding peptides for pilus proteins assembly suppression in the prevention of Salmonella-induced biofilm formation using virtual mutagenesis studies.}, journal = {In silico pharmacology}, volume = {13}, number = {1}, pages = {25}, pmid = {39944120}, issn = {2193-9616}, abstract = {UNLABELLED: Clinical isolates of Salmonella enterica contain Saf pili that establish initial bacterial attachment with the human epithelium to form biofilms which are a common cause of several abdominal complications. Due to the rise in antibiotic-resistant strains of bacteria, an alternate strategy of inhibiting the initial bacterial contact with the epithelial layers is well-studied. Saf pili undergo a chaperone-usher pathway assembly mechanism to generate its host-recognizing functional form, SafDAA. Preventing the biogenesis of the pili by targeting the SafD and SafA proteins polymerization will prevent host recognition. In this study, virtual mutagenesis studies using the recently reported X-ray crystal structure of an N-terminal peptide co-crystallized with SafD led to the design of peptides that exhibit enhanced binding with SafD compared to its native peptide. Virtual alanine mutagenesis and protein-peptide interaction studies identified several hotspot residues. Molecular dynamics simulations and binding free energy calculations identified key pairwise interactions between the designed peptides and SafD. In addition, a library of 110 peptides that are predicted to bind strongly with SafD is prepared which can serve as an excellent resource for the discovery of novel SafD-binding peptides. This work provided new insights into the design of novel anti-virulence therapies targeting Salmonella enterica.<br><br>SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40203-025-00313-9.}, }
@article {pmid39942542, year = {2025}, author = {Santamarina, MP and Giménez-Santamarina, S and Santamarina, C and Larran, S and Roselló, J}, title = {Conservation of Tiger Nut Tubers with Natural Biofilm Formulated with Thymus zygis Essential Oil.}, journal = {Molecules (Basel, Switzerland)}, volume = {30}, number = {3}, pages = {}, doi = {10.3390/molecules30030436}, pmid = {39942542}, issn = {1420-3049}, mesh = {*Oils, Volatile/pharmacology/chemistry ; *Thymus Plant/chemistry ; *Biofilms/drug effects ; *Antifungal Agents/pharmacology/chemistry ; *Cymenes/pharmacology/chemistry ; *Thymol/pharmacology/chemistry ; Cyclohexane Monoterpenes/chemistry ; Alternaria/drug effects ; Microbial Sensitivity Tests ; Plant Tubers/chemistry ; Fusarium/drug effects ; Cyperus/chemistry ; Nuts/chemistry ; }, abstract = {Cyperus esculentus L. var sativus is cultivated in Spain, only in the L'Horta Nord in the Valencia region. In this country, tubers are consumed fresh to make a popular beverage in the Valencia region called "horchata de chufa" (chufa milk). This drink is considered beneficial for human health thanks to its high nutritional value and medicinal importance in several treatments. This work evaluates the antifungal potential of the Thymus zygis essential oil against fungi found in tiger nut warehouses to preserve tubers under the best conditions. The analyzed commercial thyme essential oil belongs to the thymol/p-cymene/γ-terpinene chemotype. Thymol was found in larger quantities (51.34%), followed by the identified biogenetic precursors p-cymene (35.16%) and γ-terpinene (3.53%). Carvacrol also appeared, but in small quantities (3.53%). During in vitro tests, the T. zygis EO showed strong inhibition (98.85% to 91.81% MGI) against fungi Alternaria alternata, Fusarium andiyazi, Fusarium incarnatum, and Fusarium oxysporum at 300 µg/mL. It totally inhibited their growth (100% MGI) at 400 µg/mL, and did so strongly (75.94%, 72.02%, and 70.78%) with fungi Podospora australis, Penicillium commune, and Cladosporium subuliforme, respectively. Under in vivo conditions, formulated as a protective biofilm, and by forcing the environmental conditions of temperature and humidity to the maximum for fungus F. andiyazi growth on tiger nut tubers, the created film acted as a strong protector against fungal attacks.}, }
@article {pmid39942124, year = {2025}, author = {Shen, T and Cao, C and Zhu, R and Chen, J and Wang, F and Wang, Y}, title = {Identification of a TonB-Dependent Siderophore Receptor as a Novel Anti-Biofilm Target and Virtual Screening for Its Inhibitor in Pseudomonas fluorescens PF08.}, journal = {Foods (Basel, Switzerland)}, volume = {14}, number = {3}, pages = {}, doi = {10.3390/foods14030531}, pmid = {39942124}, issn = {2304-8158}, support = {32302168//National Natural Science Foundation of China/ ; LQ24C200014//Zhejiang Provincial Natural Science Foundation/ ; }, abstract = {Pseudomonas fluorescens is a vital food spoilage bacterium that commonly spoils foods in the biofilm state. Uncovering the targets responsible for biofilm formation and disrupting their function is a promising way to control bacterial biofilms and food spoilage. In this work, using the combination of qRT-PCR and construction of the gene deletion strain, Δtdsr, TonB-dependent siderophore receptor D7M10_RS23410 was, for the first time, proven to play an essential part in the biofilm development of P. fluorescens. By utilizing structure-based virtual screening technology, a natural compound, adenosine monophosphate (AMP), with the highest binding activity to D7M10_RS23410, was obtained as an effective biofilm inhibitor. AMP significantly decreased the cell autoaggregation and biofilm biomass at sub-MIC concentrations (2.5, 1.25, and 0.625 mg/mL), mainly through inhibiting the generation of extracellular polymeric substances (EPS) in the biofilm matrix and promoting the cell motility. Furthermore, AMP was found to form hydrogen bonds with specific amino acid residues and stretched the protein structure of D7M10_RS23410, and this structural alteration undoubtedly interfered with the functionality of the D7M10_RS23410 protein.}, }
@article {pmid39939707, year = {2025}, author = {Cai, Y and Tao, H and Gaballa, A and Pi, H and Helmann, JD}, title = {The extracytoplasmic sigma factor σ[X] supports biofilm formation and increases biocontrol efficacy in Bacillus velezensis 118.}, journal = {Scientific reports}, volume = {15}, number = {1}, pages = {5315}, pmid = {39939707}, issn = {2045-2322}, support = {41471214 and 41977035//National Natural Science Foundation of China/ ; R00 AI168483/NH/NIH HHS/United States ; DP2 AI184552/NH/NIH HHS/United States ; }, mesh = {*Bacillus/genetics/physiology/metabolism ; *Biofilms/growth &amp; development ; *Sigma Factor/genetics/metabolism ; *Fusarium/physiology ; *Plant Diseases/microbiology/prevention &amp; control ; Musa/microbiology ; Plant Roots/microbiology ; Bacterial Proteins/genetics/metabolism ; Soil Microbiology ; Biological Control Agents ; }, abstract = {Plant growth promoting rhizobacteria (PGPR) offer an environmentally friendly and sustainable approach to combat pathogens and enhance crop production. The biocontrol activity of PGPR depends on their ability to colonize plant roots and synthesize antimicrobial compounds that inhibit pathogens. However, the regulatory mechanisms underlying these processes remain unclear. In this study, we isolated and characterized Bacillus velezensis 118, a soil isolate that exhibits potent biocontrol activity against Fusarium wilt of banana. Deletion of sigX, encoding an extracytoplasmic function (ECF) sigma factor previously implicated in controlling biofilm architecture in B. subtilis, reduced biocontrol efficacy. The B. velezensis 118 sigX mutant displayed reduced biofilm formation but had only a minor defect in swarming motility and a negligible impact on lipopeptide production. These findings highlight the importance of regulatory processes important for root colonization in the effectiveness of Bacillus spp. as biocontrol agents against phytopathogens.}, }
@article {pmid39938505, year = {2025}, author = {Dib, K}, title = {Histamine Promotes Pseudomonas aeruginosa Biofilm Formation and Renders Pseudomonas aeruginosa Biofilms More Resistant to Gentamicin and Azithromycin.}, journal = {Medical principles and practice : international journal of the Kuwait University, Health Science Centre}, volume = {}, number = {}, pages = {1-16}, doi = {10.1159/000544111}, pmid = {39938505}, issn = {1423-0151}, abstract = {OBJECTIVE: Pseudomonas aeruginosa biofilms contribute to the persistent presence of this bacterium in the cystic fibrosis airways. P. aeruginosa produces histamine in vitro and expresses histamine receptors. We investigated whether histamine regulated P. aeruginosa biofilm formation in vitro and contributed to bacterial virulence in Galleria mellonella.<br><br>SUBJECT AND METHODS: P. aeruginosa biofilms were measured by staining bacteria adhered on polystyrene with crystal violet. Histamine concentrations were measured by ELISA. G. mellonella survival upon inoculation with P. aeruginosa was measured in the absence or presence of histamine.<br><br>RESULTS: The concentration of histamine in the BHI broth was 140 ng/ml (1.3 &#xf06d;M). Addition to the broth of diamine oxidase (DAO), an enzyme that catabolizes histamine, reduced by ~ 3-fold the concentration of histamine and by 2-fold PAO1 strain biofilms. Addition of histamine (10-9 M - 10-4 M) to the LB medium augmented P. aeruginosa biofilms. Maximum effects were observed with concentrations of 10-5 M and 10-8 M for the mucoid NH57388A strain and the PAO1 strain, respectively. DAO reduced mucoid NH57388A biofilms induced by histamine (10-4 M) added to the LB medium. Addition of histamine to 48 h formed biofilms reduced anti-biofilm activities of gentamicin and azithromycin. Inoculation of G. mellonella with the PAO1 strain led to augmented histamine concentration in the haemolymph. Inoculation of histamine (10-8 M) reduced the survival rate of G. mellonella infected with the PAO1 strain.<br><br>CONCLUSION: Histamine produced during periods of infection may augment P. aeruginosa virulence by promoting the biofilm mode of life of this bacterium.}, }
@article {pmid39938856, year = {2025}, author = {Kumar, A and Yadav, B and Roy, A and Mishra, P and Poluri, KM and Gupta, P}, title = {Biochemical Insights into synergistic Candida Biofilm disintegrating ability of p-cymene inclusion complex and miconazole.}, journal = {European journal of pharmacology}, volume = {}, number = {}, pages = {177365}, doi = {10.1016/j.ejphar.2025.177365}, pmid = {39938856}, issn = {1879-0712}, abstract = {Phytoactive molecules emerge as a plentiful reservoir of adjuvant and antifungal agents. The resolution of solubility and stability issues has been facilitated by developing molecular complexes or inclusion complexes of phytoactive molecules. Miconazole (MCZ) is a favoured azole with low off-target impact, however, its pharmacological efficacy requires a revamp to enhance its suitability as an antifungal drug. Hence, the present investigation delves into the mechanism of action of the p-cymene/β-cyclodextrin inclusion complex (IC) along with MCZ against Candida albicans and C. glabrata biofilms. The synergy between IC and MCZ has been estimated at a concentration of 6.25 μg/mL IC + 0.5 μg/mL MCZ with a FICI of 0.19. The prepared IC + MCZ displayed remarkable antifungal properties against planktonic and sessile growth of Candida species. IC + MCZ exhibited a notable 80% biofilm eradication potential against both species, corroborated by morphological analysis using FE-SEM. The results indicated that IC/IC+MCZ acts by disrupting the biochemical composition of the ECM, altering the surface properties of the cells, reducing ergosterol, enhancing membrane permeability, and inducing oxidative stress. In conclusion, the study highlighted the synergistic antibiofilm activity of p-cymene IC with miconazole against Candida species. In summary, IC+MCZ has been established as a potent antifouling agent against Candida species, warranting further exploration for potential formulation with additional investigations.}, }
@article {pmid39938827, year = {2025}, author = {Li, W and Huang, C and Yuan, W and Xu, T and Shan, L and Xia, W and Ren, Y and Zhang, Z and Chen, J}, title = {Effects of the histone-like protein on biofilm formation and pathogenicity of Listeria monocytogenes.}, journal = {International journal of biological macromolecules}, volume = {}, number = {}, pages = {140908}, doi = {10.1016/j.ijbiomac.2025.140908}, pmid = {39938827}, issn = {1879-0003}, abstract = {Histone-like protein HU is essential for DNA recombination, repair, and transcriptional regulation in bacteria. However, the physiological roles of HU proteins in Listeria monocytogenes (LmHU) remain unexplored. Given the significant biofilm-forming ability of this foodborne pathogen and its associated cross-contamination risks, identifying novel control targets is critical. LmHU, as the sole double-stranded DNA-binding protein in L. monocytogenes, is a promising candidate. This study systematically explored its contributions to biofilm formation, motility, and the regulation of virulence factors. The results indicated that high levels of LmHU in vivo promoted cell cohesion, leading to a chain-like structure among L. monocytogenes. Additionally, LmHU could be secreted into the biofilm matrix, reinforcing the structure by interacting with extracellular polymeric substances. However, elevated LmHU levels inhibited bacterial motility, flagellar synthesis, and host invasion in Caco-2 cells. RNA-seq analysis revealed 374 differentially expressed genes in the Lmhu mutant relative to the wild-type strain, supporting these findings. Further enrichment analysis and validation experiments suggested that Lmhu overexpression impaired trehalose utilization. These results indicate that LmHU may serve as a potential target for novel disinfectants or therapies to reduce risks associated with L. monocytogenes in food safety and public health.}, }
@article {pmid39938706, year = {2025}, author = {Li, L and Wang, Y and Hu, S and Chang, X and Ding, Q and Wang, K and Chen, Y and Zheng, J}, title = {Peroxidase-like copper-doped carbon-dots embedded in hydrogels for stimuli-responsive bacterial biofilm elimination and wound healing.}, journal = {Acta biomaterialia}, volume = {}, number = {}, pages = {}, doi = {10.1016/j.actbio.2025.02.022}, pmid = {39938706}, issn = {1878-7568}, abstract = {Bacterial biofilms and their microenvironment are significant challenges that must be faced in the design of antibacterial drugs. Microenvironment-responsive mimetic peroxidases (POD) have been demonstrated to be an efficient solution to eliminating bacterial biofilms. However, they inevitably require additional H2O2 and/or acid due to the poor permeabilities towards biofilms. Herein, we reporte POD-like copper-doped carbon dots (named CuCD1) synthesized through a facile microwave-assisted carbonization manner. The characteristics of ultrasmall size (< 5 nm) and positive charge enabled it to possess a good penetrability toward bacterial biofilm. As expected, CuCD1 showed great damage to bacteria due to the generation of hydroxyl radicals (•OH), which originated from the catalytic decomposition of endogenous H2O2 under a weak acid bacterial biofilm microenvironment. This highly increased oxidative stress resulted in the alteration of cell membrane permeability, subsequent cell death, and the final eradication of the fragments of bacterial biofilm and the exposed bacteria. Moreover, to verify the practicality in vivo, CuCD1 was introduced to a routine hydrogel that was crosslinked by carboxymethyl chitosan (CMCS) and oxidized dextran (ODEX). In comparison with the control groups, the composite hydrogel, i.e., CuCD1-CMCS-ODEX revealed better antibacterial performance and thus accelerated wound healing and collagen disposition. This work would open opportunities to design CDs-based biofilm microenvironment-responsive antibacterial nanoagents. STATEMENT OF SIGNIFICANCE: (1) Ultrasmall size, positively charged, peroxidase (POD)-like CuCD1 were designed and harvested by a facile microwave-assisted carbonization method. (2) CuCD1 revealed a competitive in vitro antibacterial performance, good penetrability, and microenvironment-responsive clearing capacity towards bacterial biofilm. (3) By composing with CMCS-ODEX hydrogel, the composite hydrogel could continuously eliminate bacteria, promote wound healing, as well as collagen disposition. (4) This work would provide a new strategy in the design of CDs-based biofilm microenvironment-responsive antibacterial nano-agents.}, }
@article {pmid39935129, year = {2025}, author = {Gao, Y and Chen, X and Zou, Z and Qi, D and Geng, Y and Wang, Z and Zhang, Z and He, C and Yu, J}, title = {Tissue-Adhesive and Antibacterial Hydrogel Promotes MDR Bacteria-Infected Diabetic Wound Healing via Disrupting Bacterial Biofilm, Scavenging ROS and Promoting Angiogenesis.}, journal = {Advanced healthcare materials}, volume = {}, number = {}, pages = {e2404889}, doi = {10.1002/adhm.202404889}, pmid = {39935129}, issn = {2192-2659}, support = {2022YFE0138500//National Key Research and Development Program of China/ ; 52425312 52473157//National Natural Science Foundation of China/ ; }, abstract = {Effective treatment of diabetic wounds remains challenging because of multidrug-resistant (MDR) bacterial infections, excessive oxidative stress, and impaired angiogenesis. In this study, a tissue-adhesive and antibacterial hydrogel incorporating MXene and deferoxamine (DFO)-loaded microspheres is developed for the treatment of MDR bacteria-infected diabetic wounds. The hydrogel is built based on covalent crosslinking between ε-poly(L-lysine) and o-phthalaldehyde-terminated four-arm poly(ethylene glycol). The hydrogel exhibited excellent mechanical properties, tissue adhesion strength, biocompatibility, and biodegradability. Under near-infrared (NIR) irradiation, the MXene converted light into heat and elevated the local temperature rapidly, enabling the rapid disintegration of MDR bacterial biofilms. Simultaneously, the hydrogel exerted inherent antibacterial activity, persistently killing planktonic bacteria, and effectively controlling wound infections. The encapsulated DFO is then released from the hydrogel in a sustained and controlled manner, and promoted angiogenesis during diabetic wound healing. Additionally, MXenes can scavenge excessive reactive oxygen species and alleviate wound inflammation. In the methicillin-resistant Staphylococcus aureus-infected diabetic wound model in mice, the composite hydrogel along with NIR irradiation efficiently reduced the infectious bacteria, and accelerated the wound healing by promoting angiogenesis and alleviating inflammation. This composite hydrogel has great clinical potential for the treatment of diabetic wounds, particularly in challenging healing environments involving motion and infection.}, }
@article {pmid39934529, year = {2025}, author = {Roy, R and Das, A and Ganguly, D and Chakraborty, P and Paul, P and Das, S and Maity, A and Malik, M and Tribedi, P}, title = {Cuminaldehyde synergistically enhances the antimicrobial and antibiofilm potential of gentamicin: A direction towards an effective combination for the control of biofilm-linked threats of Staphylococcus aureus.}, journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]}, volume = {}, number = {}, pages = {}, pmid = {39934529}, issn = {1678-4405}, support = {TNU/R&amp;D/M/11//The Neotia University/ ; }, abstract = {Staphylococcus aureus, a Gram-positive, coccus-shaped bacterium often causes several infections on human hosts by exploiting biofilm. This current work investigates a potential strategy to manage the threats of biofilm-linked infections by embracing a combinatorial approach involving cuminaldehyde (phytochemical) and gentamicin (antibiotic). Despite showing antimicrobial properties individually, cuminaldehyde and gentamicin could exhibit enhanced antimicrobial potential when used together against S. aureus. The fractional inhibitory concentration index (FICI = 0.36) suggested that the selected compounds (cuminaldehyde and gentamicin) offered synergistic interaction while showing antimicrobial potential against the same organism. A series of experiments indicated that the selected compounds (cuminaldehyde and gentamicin) showed substantial antibiofilm potential against S. aureus when combined. The increased antibiofilm potential was linked to the accumulation of reactive oxygen species (ROS) and increased cell membrane permeability. Additionally, the combination of the selected compounds (cuminaldehyde and gentamicin) also impeded the cell surface hydrophobicity of S. aureus, aiding in the prevention of biofilm formation. The present study also showed that combining the mentioned compounds (cuminaldehyde and gentamicin) notably reduced the secretion of several virulence factors from S. aureus. Furthermore, the current research showed that these compounds (cuminaldehyde and gentamicin) could also exhibit antibiofilm potential against the clinical strains of Methicillin-Resistant S. aureus (MRSA). Taken together, this innovative approach not only enhances the potential of existing standard antibiotics but also opens up new therapeutic possibilities for combating biofilm-related infections.}, }
@article {pmid39932517, year = {2025}, author = {Alobaid, SA and Shrestha, S and Tasseff, M and Wang, B and van Hoek, ML and Dutta, PK}, title = {Activity of silver-zinc nanozeolite-based antibiofilm wound dressings in an in vitro biofilm model and comparison with commercial dressings.}, journal = {Discover nano}, volume = {20}, number = {1}, pages = {26}, pmid = {39932517}, issn = {2731-9229}, support = {2025819//National Science Foundation/ ; 2025819//National Science Foundation/ ; 2025819//National Science Foundation/ ; 2025819//National Science Foundation/ ; 2025819//National Science Foundation/ ; 2025819//National Science Foundation/ ; }, abstract = {BACKGROUND: Infected wounds are a major health problem as infection can delay wound healing. Wound dressings play an important part in wound care by maintaining a suitable environment that promotes healing. Silver sulfadiazine dressings have been used to prevent infection in burn wounds. Presently, many commercial silver dressings have obtained FDA clearance.<br><br>RESULTS: In this study, we report on a novel silver dressing using microporous aluminosilicate zeolites, termed ABF-XenoMEM. Silver and zinc ions are encapsulated in the zeolite supercages. We show that the silver-zinc zeolite (AM30) alone is effective at inhibiting biofilm formation. The encapsulation protects the silver from rapidly precipitating in biological fluids. We exploit the negatively charged zeolite surface to associate positively charged quaternary ammonium ions (quat) with the zeolite. The combination of the AM30 with the quat enhances the antimicrobial activity. The colloidal nature of the zeolite materials makes it possible to make uniform deposits on a commercial extracellular matrix membrane to develop the final dressing (ABF-XenoMEM). The optimum loading of silver, zinc, and quat on the dressing was found to be 30, 3.7, and 221&#xa0;&#xb5;g/cm[2]. Using a colony biofilm model, the activity of ABF-XenoMEM is compared with four well-studied silver-based commercial dressings towards mature biofilms of Pseudomonas aeruginosa PAO1 (ATCC 4708) and methicillin-resistant Staphylococcus aureus (ATCC 33592). Cytotoxicity of the dressings was examined in HepG2 cells using the MTT assay.<br><br>CONCLUSION: This study shows that the ABF-XenoMEM is competitive with extensively used commercial wound dressings in a colony biofilm model. Nanozeolite-entrapped silver/zinc antimicrobials in association with quat have the potential for application in biofilm-infected wounds and require animal and clinical studies for definitive proof.}, }
@article {pmid39932315, year = {2025}, author = {He, Y and Qin, Y and Greenwich, J and Balaban, S and Darcera, MVL and Gozzi, K and Chai, Y}, title = {A novel regulation on the developmental checkpoint protein Sda that controls sporulation and biofilm formation in Bacillus subtilis.}, journal = {Journal of bacteriology}, volume = {}, number = {}, pages = {e0021024}, doi = {10.1128/jb.00210-24}, pmid = {39932315}, issn = {1098-5530}, abstract = {UNLABELLED: Biofilm formation by Bacillus subtilis is triggered by an unusually simple environmental sensing mechanism. Certain serine codons, the four TCN codons (N for A, T, C, or G), in the gene for the biofilm repressor SinR caused lowered SinR translation and subsequent biofilm induction during transition from exponential to stationary growth. Global ribosome profiling showed that ribosomes pause when translating the four UCN (U for T on the mRNA) serine codons on mRNA, but not the two AGC/AGU serine codons. We proposed a serine codon hierarchy (AGC/AGT vs TCN) in that genes enriched in the TCN serine codons may experience reduced translation efficiency when serine is limited. In this study, we designed an algorithm to score all protein-coding genes in B. subtilis NCIB3610 based on the serine codon hierarchy. We generated a short list of 50 genes that could be subject to regulation by this novel mechanism. We further investigated one such gene from the list, sda, which encodes a developmental checkpoint protein regulating both sporulation and biofilm formation. We showed that synonymously switching the TCN serine codons to AGC in sda led to delayed biofilm formation and sporulation. This engineered strain also outgrew strains with other synonymously substituted sda alleles (TCN) in competition assays for biofilm formation and sporulation. Finally, we showed that the AGC serine codon substitutions in sda elevated the Sda protein levels. This serine codon hierarchy-based novel signaling mechanism could be exploited by bacteria in adapting to stationary phase and regulating important biological processes.<br><br>IMPORTANCE: Genome-wide ribosome profiling in Bacillus subtilis shows that under serine limitation, ribosomes pause on the four TCN (N for A, C, G, and T), but not AGC/AGT serine codons, during translation at a global scale. This serine codon hierarchy (AGC/T vs TCN) differentially influences the translation efficiency of genes enriched in certain serine codons. In this study, we designed an algorithm to score all 4,000+ genes in the B. subtilis genome and generated a list of 50 genes that could be subject to this novel serine codon hierarchy-mediated regulation. We further investigated one such gene, sda, encoding a developmental checkpoint protein. We show that sda and cell developments controlled by Sda are also regulated by this novel mechanism.}, }
@article {pmid39931412, year = {2025}, author = {Yousaf, A and Ullah, MH and Nawaz, H and Majeed, MI and Rashid, N and Alshammari, A and Albekairi, NA and Ali, A and Hussain, M and Salfi, AB and Aslam, MA and Idrees, K and Ditta, A}, title = {SERS-assisted characterization of cell biomass from biofilm-forming Acinetobacter baumannii strains using chemometric tools.}, journal = {RSC advances}, volume = {15}, number = {6}, pages = {4581-4592}, pmid = {39931412}, issn = {2046-2069}, abstract = {Acinetobacter baumannii (A. baumannii) is an emerging Gram-negative nosocomial pathogen responsible for infection on a global scale. It has the ability to develop biofilms on different surfaces, especially abiotic surfaces, which is considered a major contributor of its pathogenicity. Surface-enhanced Raman spectroscopy (SERS) holds great potential as an effective method for identifying and characterizing the biochemical composition of biofilm-forming species. In this study, cell mass samples from different strains of A. baumannii, categorized based on their biofilm-forming ability (strong, medium and non-biofilm forming) using a 96-well microtiter plate assay (MTP), were analyzed by SERS. The identified spectral features of the SERS spectra were used to characterize bacterial strains capable of producing biofilms. Silver nanoparticles (Ag-NPs) served as the SERS substrate to differentiate biofilm-forming strains of A. baumannii. Chemometric tools, such as principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA), were employed for the classification and differentiation of SERS spectra from bacterial strains with varying biofilm-producing capacities, achieving 100% sensitivity, 94.3% specificity, and an area under the curve (AUC) value of 0.81 through Monte Carlo cross-validation. Furthermore, K-fold (Leave-K-out cross-validation (LKOCV)) was applied to verify the robustness of the PLS-DA model, and the AUC value was found to be 0.90, with a sensitivity of 100% and specificity of 98%. These results demonstrate that the PLS-DA model is highly effective for the differentiation and classification of bacterial strains with varying capacities for biofilm production.}, }
@article {pmid39930718, year = {2025}, author = {Zhao, X and Li, J and Zhang, P and Xiao, C and Chen, L}, title = {Acid-Responsive Bacteria-Targeted Zinc-Porphyrin Based Sonosensitizer with Enhancing Antibacterial Efficacy and Biofilm Eradication for Infected Wounds Healing.}, journal = {Advanced healthcare materials}, volume = {}, number = {}, pages = {e2404643}, doi = {10.1002/adhm.202404643}, pmid = {39930718}, issn = {2192-2659}, support = {51973025//National Natural Science Foundation of China/ ; 52222307//National Natural Science Foundation of China/ ; 20220204107YY//Jilin Science and Technology Bureau/ ; 20230204086YY//Jilin Science and Technology Bureau/ ; 2023C028-4//Jilin Province Development and Reform Commission/ ; }, abstract = {Diseases caused by bacterial infections place a significant burden on global public health. Sonodynamic therapy (SDT), as an emerging antibacterial treatment, faces clinical challenges due to the non-polar nature of most sonosensitizers. To address this, an acid-responsive zinc-porphyrin-based sonosensitizer (Zn-TCPP) is developed via a simple thermal reaction, which is then coated with phenylboronic acid-modified hyaluronic acid (B-HA), to fabricate B-HA@Zn-TCPP. While in the mildly acidic microenvironment mimicking an infected wound site, the released B-HA@Zn-TCPP achieves effective SDT activity. The disruption of the bacterial membrane and the levels of intracellular reactive oxygen species (ROS) verified that the inhibition rate can reach 99% within 5 min, without any development of resistance after 15 consecutive generations of culture. Additionally, under ultrasound (US) -mediated cavitation, B-HA@Zn-TCPP exhibits excellent penetration into biofilms, achieving a 90.04% bactericidal rate for bacteria within biofilms. In vivo studies further demonstrated that B-HA@Zn-TCPP can effectively accelerate the healing of bacterial infected wounds with a wound healing rate of 98.65% within 9 days. Therefore, B-HA@Zn-TCPP as a novel sonosensitizer offers a viable strategy to overcome the limitations of traditional sonosensitizers for the bacterial wound infections.}, }
@article {pmid39930100, year = {2025}, author = {Hou, K and Song, Q and Xu, J and Ren, X and Wang, Y and Yuan, S and Wang, W and Hu, ZH}, title = {Coupling of titanium dioxide loaded carrier and denitrification biofilm for the advanced treatment of micro-polluted water.}, journal = {Environmental science and pollution research international}, volume = {}, number = {}, pages = {}, pmid = {39930100}, issn = {1614-7499}, abstract = {TiO2 was immobilized on a polypropylene polyhedral (PP) ball using polyamide (PA) hot melt adhesive to generate floating photocatalyst TiO2-PA/PP with high photocatalytic activity, which was further coupled with denitrification biofilm to form TiO2-PA/PP biofilm system. The analysis of SEM, EDS, XRD, and FTIR confirmed that TiO2 was immobilized on the surface of PP without any changes in the crystal structure of TiO2. The photocatalytic experiments showed that the degradation efficiencies of p-phenylenediamine, sucrose, humic acid, and bovine albumin by TiO2-PA/PP were 58.3%, 48.0%, 97.1%, and 66.6%, respectively. •O2[-] and h[+] were the key reactive oxygen species (ROSs) in photocatalytic degradation of organic matter in the TiO2-PA/PP system under solar irradiation. In the synthetic water, 95.5% humic acid and 43.2% nitrate were simultaneously removed in TiO2-PA/PP biofilm reactor, confirming the coupling of photocatalytic degradation and denitrification. In the actual micro-polluted surface water, the coupling photocatalytic and biofilm reactor reduced chemical oxygen demand (COD) by 68.4% and nitrate by 38.9% in 480 min. This study provided a new option for the in-situ removal of organic matter and nitrate from micro-polluted surface water.}, }
@article {pmid39929443, year = {2025}, author = {Lakshminarasimman, N and McKnight, MM and Neufeld, JD and Parker, W}, title = {Characterizing biofilm thickness, density, and microbial community composition in a full-scale hybrid membrane aerated biofilm reactor.}, journal = {Bioresource technology}, volume = {}, number = {}, pages = {132207}, doi = {10.1016/j.biortech.2025.132207}, pmid = {39929443}, issn = {1873-2976}, abstract = {This study examined biofilm thickness, density, and microbial composition in a full-scale MABR treating municipal wastewater, focusing on their spatial and operational variability. The MABR cassette arrangement created a thickness gradient, with biofilms in the front cassettes more than twice as thick as those at the back. Lower scouring intensity due to reduced airflow resulted in thicker biofilms. Microbial communities varied longitudinally and by operational phase, with thicker biofilms having a higher relative abundance of anaerobic microorganisms, such as fermenters and sulfur reducers, and fewer aerobic nitrifiers. Nitrosomonas were the main ammonia oxidizers, while Nitrospira and Ca. Nitrotoga dominated as nitrite oxidizers. The 16S RNA gene profiles showed strong correlations with biofilm thickness (R[2] = 0.8) and nitrification rates (R[2] = 0.4). Full-scale MABR biofilm characteristics have not been studied before. Study findings have practical implications for better modeling practices and improved design of future MABR facilities.}, }
@article {pmid39929166, year = {2025}, author = {Zhang, B and Zhang, A and Hou, S and Yang, J and Hu, T and Yang, Y and Lei, L and Huang, R}, title = {Streptococcus mutans GcrR regulates oral biofilm from a cariogenic state to a non-cariogenic state by affecting exopolysaccharides production and biofilm homeostasis.}, journal = {Caries research}, volume = {}, number = {}, pages = {1-26}, doi = {10.1159/000544075}, pmid = {39929166}, issn = {1421-976X}, abstract = {INTRODUCTION: Dental caries is a non-communicable disease caused by dysbiosis of dental biofilm. S. mutans is considered the major pathogen. The orphan response regulator GcrR negatively regulates exopolysaccharides (EPSs) synthesis in S. mutans. We aimed to investigate the effect of GcrR on the cariogenicity of oral biofilms. A multispecies biofilm model was constructed, including S. mutans, S. sanguinis, and S. gordonii.<br><br>METHODS: The morphology of multispecies biofilms was detected through scanning electron microscopy (SEM), and the structure was observed using confocal laser scanning microscopy (CLSM). The microbial composition was measured by fluorescence in situ hybridization (FISH) and qPCR. The expression of genes was detected by quantitative RT-PCR (qRT-PCR). A specific pathogen-free (SPF) rat model was used to assess the cariogenicity of the multispecies biofilms.<br><br>RESULTS: The architecture of the biofilm was significantly impaired when gcrR-overexpressed S. mutans incubated with S. sanguinis, and S. gordonii (SmugcrR++S.s+S.g). The biofilm exhibited a decrease in the production of water-insoluble glucans (WIGs) and water-soluble glucans (WSGs), consistent with a decreased expression of EPS synthesis-related genes. The SmugcrR++S.s+S.g biofilm exhibited an increase in non-cariogenic species with lower lactic acid production. Furthermore, SmugcrR++S.s+S.g biofilm exhibited reduced cariogenicity.<br><br>CONCLUSION: The biofilm cariogeneicity could be shifted to a less cariogenic state by increased expression of the GcrR regulator.}, }
@article {pmid39928650, year = {2025}, author = {Gilmore, AL and Vu, H and Martinez, T and Peniata, L and Kawaguchi, B and Armbruster, DA and Ashton, NN and Williams, DL}, title = {In vitro antibiofilm efficacy of ertapenem, tobramycin, and moxifloxacin against biofilms grown in a glass bead or CDC Biofilm Reactor®.}, journal = {PloS one}, volume = {20}, number = {2}, pages = {e0318487}, pmid = {39928650}, issn = {1932-6203}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Tobramycin/pharmacology ; *Moxifloxacin/pharmacology ; *Pseudomonas aeruginosa/drug effects/growth &amp; development/physiology ; *Anti-Bacterial Agents/pharmacology ; *Staphylococcus aureus/drug effects/growth &amp; development/physiology ; *Ertapenem/pharmacology ; beta-Lactams/pharmacology ; Microbial Sensitivity Tests ; Bioreactors/microbiology ; Glass/chemistry ; Fluoroquinolones/pharmacology ; }, abstract = {Laboratory grown biofilms are used to simulate bacterial growth in diverse environmental conditions and screen the effectiveness of anti-biofilm therapies. Recently, we developed a glass bead biofilm reactor that utilizes low broth volume to provide high-throughput biofilm growth for testing and translation across the research continuum (e.g., benchtop assays to preclinical models). Bioburden per mm2 surface area of Staphylococcus aureus and Pseudomonas aeruginosa biofilms were comparable on beads and CDC Biofilm Reactor® coupons. In this study, we hypothesized that biofilms grown on beads would be more susceptible to ertapenem, moxifloxacin, and tobramycin than those grown on coupons. Results indicated a significant reduction in S. aureus bioburden on glass beads compared to glass coupons following treatment with ertapenem (p = 0.005) and tobramycin (p = 0.014). P. aeruginosa biofilms had smaller differences in antibiotic response between the two systems. There was a significantly greater reduction in bead P. aeruginosa biofilm than coupon when treated with tobramycin (p = 0.035). This work offered insight into how the bead biofilm reactor could be used as a tool for antibiotic screening and translation across the continuum of in vitro to in vivo systems that support development of antimicrobial technology.}, }
@article {pmid39927357, year = {2024}, author = {Al-Bukhalifa, MA and Al-Tameemi, HM}, title = {First whole genome sequencing of Staphylococcus aureus isolates from Iraq: Insights into zoonotic relations and biofilm-related genes.}, journal = {Open veterinary journal}, volume = {14}, number = {12}, pages = {3269-3288}, pmid = {39927357}, issn = {2218-6050}, mesh = {*Biofilms ; Animals ; *Staphylococcus aureus/genetics/isolation &amp; purification/physiology ; Humans ; *Staphylococcal Infections/veterinary/microbiology ; *Whole Genome Sequencing ; Cats ; Iraq ; *Genome, Bacterial ; Dogs ; Cattle ; Sheep ; Zoonoses/microbiology ; }, abstract = {BACKGROUND: Staphylococcus aureus is a significant zoonotic pathogen capable of causing infections in both humans and animals. The bacterium's capacity to develop biofilms and resistance to many different antibiotics has raised significant concerns for public health. Furthermore, studies have demonstrated that horizontal gene transfer enables the transfer of deleterious features between strains found in humans and animals, consequently rendering treatment and control efforts more challenging.<br><br>AIM: This study aimed to investigate the relationships between human and animal isolates and biofilm-associated genes in local S. aureus strains using whole genome sequencing technique.<br><br>METHODS: We examined 111 suspected cases of S. aureus infection in humans and in animals and screened all S. aureus -positive isolates (11 isolates) for biofilm formation and antimicrobial profiles. Additionally, we sequenced and studied five S. aureus genomes isolated from humans, cows, sheep, cats, and dogs for significant biofilm-related genes and predicted their loci following annotation and deposition in the NCBI database.<br><br>RESULTS: The study showed that the isolates have genome sizes between 2.7 and 2.8 megabases, a GC content of 32.8%-33.1%, and a coding sequence count between 2,718 and 2,838. The cow isolate (MHB) and cat isolate (MHF) exhibited substantial genomic similarities with human isolates of S. aureus (N315) and the type strain of S. aureus (DSM 20231). The genomes of the human isolate (MHH) and the dog isolate (MHC) were comparable to S. aureus (N315). The sheep isolate (MHO) showed lesser genomic similarity and was closely related to S. aureus subsp. anaerobius. The genomes were submitted to the NCBI database with the following accession numbers: MHB (GCA_040196135.1), MHH (GCA_040196155.1), MHO (GCA_040195495.1), MHF (GCA_040195555.1), and MHC (GCA_040195445.1). The isolates were categorized by PubMLST typing into MHC (ST-1156), MHB (ST-6), MHF (ST-6), and MHO (a unique ST). We identified the accession numbers, locations, and lengths of biofilm-associated genes and regulators within the studied genomes.<br><br>CONCLUSION: The study is the first to conduct complete genome sequencing of Staphylococcus aureus in Iraq, allowing analysis of biofilm-associated genes in local isolates. It provides the first large-scale genomic investigation of genetic relationships among animal and human isolates in Iraq.}, }
@article {pmid39927094, year = {2025}, author = {Tulin, G and Méndez, AAE and Figueroa, NR and Smith, C and Folmer, MP and Serra, D and Wade, JT and Checa, SK and Soncini, FC}, title = {Integration of BrfS into the biofilm-controlling cascade promotes sessile Salmonella growth at low temperatures.}, journal = {Biofilm}, volume = {9}, number = {}, pages = {100254}, pmid = {39927094}, issn = {2590-2075}, support = {R35 GM144328/GM/NIGMS NIH HHS/United States ; }, abstract = {Biofilm formation is stimulated by different stress-related physiological and environmental conditions. In Salmonella and Escherichia coli, curli fibers and phosphoethanolamine-cellulose are the major extracellular components of biofilms. The production of both is under the control of CsgD, a transcriptional regulator whose expression is modulated by a number of factors responding to different signals. The atypical MerR-like regulator MlrA is key in the activation of csgD transcription in both Salmonella and E. coli. Recently, MlrB, a SPI-2-encoded MlrA-like regulator that counteracts MlrA by repressing csgD transcription and biofilm formation inside macrophages was identified. Here, we characterize STM1266, a Salmonella-specific MlrA-like regulator, recently renamed BrfS. In contrast to mlrA, brfS transcription increases in minimal growth media and at 20 °C, a temperature not commonly tested in laboratories. Under these conditions, as well as in salt-limited rich medium, deletion or overexpression of brfS affects extracellular matrix production. Using transcriptomics, we uncovered genes under BrfS control relevant for biofilm formation such as csgB and bapA. Transcriptional analysis of these genes in mutants lacking brfS, csgD or both, indicates that BrfS controls curli biosynthesis both in a CsgD-dependent and independent manner. By contrast, at low temperatures, bapA transcription depends only on BrfS, and neither deletion of csgD nor of mlrA modify its expression. Based on these results, we propose that BrfS contributes to Salmonella persistence in the environment, where the pathogen encounters low temperatures and nutrient limitation.}, }
@article {pmid39926921, year = {2024}, author = {Priyadharsana, PS and Dubey, V and Kaur, P and Nagar, P and Chethan, J and Priyanka, BB}, title = {Evaluation of Antimicrobial Agents, Irrigation Solutions, and Surface Disinfection Techniques for Preventing Bacterial Contamination and Biofilm Formation on Implant Surfaces In Vitro.}, journal = {Journal of pharmacy &amp; bioallied sciences}, volume = {16}, number = {Suppl 4}, pages = {S3631-S3633}, pmid = {39926921}, issn = {0976-4879}, abstract = {BACKGROUND: Peri-implant diseases, driven by bacterial biofilms, threaten long-term implant success. This study evaluated various antimicrobial agents for preventing bacterial contamination and biofilm formation on implant surfaces.<br><br>METHODS: Ultraviolet radiation type C (UV-C) light, povidone-iodine (PVP-I), chlorhexidine (CHX), and hydrogen peroxide (H2O2) were tested against bacterial cultures. Log reduction values quantified bacterial population decrease. Biofilm formation was assessed using crystal violet staining and optical density at 570 (OD570) measurements.<br><br>RESULTS: UV-C and PVP-I showed the highest log reductions (3.7067, 3.6200), followed by CHX (2.9467) and H2O2 (2.3800). UV-C and PVP-I most effectively inhibited biofilm formation (OD570: 0.0600, 0.0800), followed by CHX (0.1200) and H2O2 (0.1767).<br><br>CONCLUSION: UV-C and PVP-I demonstrated superior efficacy in reducing bacterial load and inhibiting biofilm formation, suggesting potential as valuable tools for preventing and managing peri-implant infections.}, }
@article {pmid39926624, year = {2025}, author = {Ezzariga, N and Zouhari, O and Rhars, A and Lemkhente, Z and Aghrouch, M}, title = {Biofilm and Antibiotic Resistance Study of Bacteria Involved in Nosocomial Infections.}, journal = {Cureus}, volume = {17}, number = {2}, pages = {e78673}, pmid = {39926624}, issn = {2168-8184}, abstract = {Nosocomial infections are increasingly problematic due to growing bacterial resistance. Biofilms play a key role in the persistence of these infections, leading to treatment failures and poor patient outcomes. Addressing antibiotic resistance within biofilms is especially critical in hospitals, making it essential to develop new strategies to manage biofilm-related infections and curb bacterial resistance. The study, conducted at the regional hospital center in Agadir, Morocco, analyzed 75 bacteria (37 antibiotic-sensitive and 38 resistant). Seven bacteria were isolated from catheters, and others from preserved samples. Biofilm formation was assessed using the tissue culture plate (TCP) method, involving strain recovery; culture on cystine, lactose, electrolyte-deficient (CLED) medium; microplate inoculation; staining with crystal violet; and optical density (OD) measurement. The results showed that 77.33% of the bacteria formed biofilms. All catheter-isolated bacteria showed biofilm formation. Strong biofilm production was observed in 66.67% of Acinetobacter baumannii and in most Pseudomonas aeruginosa strains. Enterobacteriaceae also demonstrated significant biofilm formation. Notably, 70% of carbapenem-resistant bacteria showed strong biofilm production. Most nosocomial bacteria form biofilms, with a higher prevalence in antibiotic-resistant strains. Sensitive bacteria also form biofilms but less frequently. Bacterial conjugation may facilitate the acquisition of carbapenem resistance within biofilms.}, }
@article {pmid39926343, year = {2025}, author = {Liu, Y and Chen, F and He, Y and Wang, Y and Zhu, T and Tong, Y and Zhao, Y and Ni, BJ and Liu, Y}, title = {Evaluation of nitrous oxide reduction in solid carbon source-driven counter-diffusional biofilm denitrification system.}, journal = {Water research X}, volume = {27}, number = {}, pages = {100306}, pmid = {39926343}, issn = {2589-9147}, abstract = {Solid carbon-driven biofilm system can provide sufficient carbon source for denitrification, while its counter-diffusional structure could inevitably induce the delayed carbon-nitrogen contact and electron transport, further affecting carbon footprints mainly contributed by nitrous oxide (N2O) at wastewater treatment plants (WWTPs). However, the detailed understanding of N2O dynamics during solid-phase denitrification (SPD) has not been disclosed. In this work, a fixed bed bioreactor driven by polycaprolactone (PCL) was constructed and operated over 180 days, achieving 97 %-99 % of total nitrogen (TN) removal efficiency. Biochemical results indicated that under the condition that each nitrogen oxide (NO x) concentration was maintained at 30 mg-N/L, the electron competition between upstream and downstream electron pools was still observed during PCL-driven denitrification even providing sufficient carbon source. For example, under the coexistent nitrate (NO3 [-])+ nitrite (NO2 [-])+N2O condition, few electrons (i.e., 12.6 %) distributed to N2O reductase (Nos), significantly decreasing the N2O reduction rate (i.e., 1.42 mg/g VSS/h). Under the condition that TN concentration was maintained at 30 mg-N/L, the TN removal rate in the scheme containing NO3 [-]+NO2 [-]+N2O was observed to be 1.75-2.3 times higher than that of the scheme with sole NO x of 30 mg-N/L. This suggested that when treating wastewater containing multiple NO x , the PCL-driven biofilm denitrification system can not only relatively improve the total nitrogen removal efficiency, but also relatively alleviate N2O emissions. The higher abundance of Bacteroidota and Comamonadaceae ensured the stable carbon source release and nitrogen conversion states.}, }
@article {pmid39925995, year = {2024}, author = {Angela, T and Wahyuni, S and Halim, S}, title = {The effect of soaking heat-polymerized acrylic resin denture base in avocado seed extract (Persea americana Mill.) on the inhibition of denture-plaque microorganisms biofilm growth.}, journal = {F1000Research}, volume = {13}, number = {}, pages = {933}, pmid = {39925995}, issn = {2046-1402}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Persea/microbiology/chemistry ; *Seeds/drug effects ; *Plant Extracts/pharmacology/chemistry ; *Acrylic Resins/chemistry/pharmacology ; Hot Temperature ; Polymerization ; Dental Plaque/microbiology ; }, abstract = {BACKGROUND: Heat polymerized acrylic (HPA) resins are known to have high porosity that contributes to increased surface roughness and microcrack formation in stress areas. This facilitates the attachment and growth of polymicrobial biofilms contributing to increased antimicrobial resistance. Many research had been carried out on avocado seeds, but no research that studies avocado seeds effect on denture-plaque microorganism biofilm on HPA resin has been found.<br><br>METHODS: This study used 144 samples (n=144), namely HPA resin discs covered with mono-species and polymicrobial biofilms. The discs were soaked for 8 hours in the 5%, 10%, 15%, 20% avocado seed extract, positive control (alkaline peroxide), and negative control (aquadest). Each disc was shaken with a vortex mixer for 1 minute, and 100 &#x3bc;L was added into 96-well microplates with three times repetition and incubated for 24 hours. A microtiter plate biofilm formation assay was then conducted The inhibition values were determined from the percentage inhibition value formula which required absorption values from a microplate reader (595 nm). The research data were analyzed using a univariant test, and a one-way ANOVA test, accompanied by Welch ANOVA on non-homogenous data.<br><br>RESULTS: In this research, it was found that the MBIC 50 of avocado seed extract against the mono-species of C. albicans (5%), C. glabrata (5%), A. odontolyticus (15%), S. gordonii (15%), S. aureus (10%), while against polymicrobial was 20%. There was a significant effect of soaking HPA resin in avocado seed extract on the inhibition of mono-species and polymicrobial biofilms with a value of p<0.001 (p<0.05).<br><br>CONCLUSION: The MBIC 50 of avocado seed extract in polymicrobial biofilm group was higher than that in the mono-species biofilm groups. Although alkaline peroxide showed higher inhibition value than that of the MBIC 50 in polymicrobial biofilm group, 20% avocado seed extract was concluded effective as it inhibited >50% polymicrobial biofilm.}, }
@article {pmid39925594, year = {2025}, author = {Guruswamy Pandian, AP and Ramachandran, AK and Kodaganallur Pitchumani, P and Mathai, B and Thomas, DC}, title = {Evaluation of Anti-Biofilm Property of Zirconium Oxide Nanoparticles on Streptococcus mutans and Enterococcus faecalis: An In Vitro Study.}, journal = {Cureus}, volume = {17}, number = {1}, pages = {e77199}, pmid = {39925594}, issn = {2168-8184}, abstract = {Introduction The prevalence of dental caries and endodontic infections caused by bacteria such as Streptococcus mutans and Enterococcus faecalis poses a significant challenge in root canal treatment. These pathogens exhibit significant resistance to antimicrobial treatments due to their ability to form biofilms, complex microbial communities encased in a self-produced extracellular polymeric substance (EPS). Despite advancements in treatment strategies, the failure rate remains high due to the difficulty in completely eradicating microbial populations within the complex root canal system. The increasing prevalence of antibiotic resistance has driven the need for novel antimicrobial agents and strategies to target biofilms. In this study, we evaluated the potential of zirconium oxide nanoparticles (ZrO2 NPs) in eradicating biofilms formed by S. mutans and E. faecalis, two key pathogens involved in these infections. Materials and methods ZrO2 NPs were characterized and evaluated for their antimicrobial properties against E. faecalis and S. mutans biofilms. The nanoparticles were characterized using scanning electron microscopy and energy-dispersive X-ray spectroscopy. Biofilm quantification was performed using a crystal violet staining assay. The minimum biofilm eradication concentrations of ZrO2 NPs against the bacterial strains were determined. Results ZrO2 NPs used in our study were found to have zirconium predominantly with no impurities. Also, the average particle size was less than 30 nm with a spherical shape arranged in clusters. These characterizations were performed considering the vital role of these properties in obtaining the desired antibacterial/anti-biofilm properties of nanoparticles. ZrO2 NPs were capable of eradicating the biofilm formed by both S. mutans and E. faecalis at concentrations greater than 22.8 μg/mL. The results suggest that ZrO2 NPs could be used as a novel approach for combating biofilm-related infections. Conclusion Our findings suggest that ZrO2 NPs have the potential to be a promising antibiofilm agent in root canal treatment, offering a new approach to combat these persistent infections. Further research is warranted to explore the full potential of nanomaterials in improving treatment outcomes in endodontic infections.}, }
@article {pmid39925377, year = {2025}, author = {Priyanka,  and Sharma, M and Vaid, B and Bharti, R and Raut, S and Jolly, RS and Khatri, N}, title = {Comprehensive safety and toxicity analysis of 2,2'-Bipyridine derivatives in combating MRSA biofilm formation and persistence.}, journal = {Frontiers in cellular and infection microbiology}, volume = {15}, number = {}, pages = {1493679}, pmid = {39925377}, issn = {2235-2988}, mesh = {*Biofilms/drug effects ; *Methicillin-Resistant Staphylococcus aureus/drug effects ; Animals ; *2,2'-Dipyridyl/pharmacology/chemistry ; Mice ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Staphylococcal Infections/drug therapy ; *Microbial Sensitivity Tests ; Disease Models, Animal ; Cell Survival/drug effects ; Hemolysis/drug effects ; Humans ; }, abstract = {INTRODUCTION: Methicillin-resistant Staphylococcus aureus (MRSA) infections have become arduous to treat due to their capacity to form biofilms, develop persistence, and exhibit significant antimicrobial resistance. These factors contribute to the complexity of managing MRSA infections and highlight the urgent need for innovative treatment strategies.<br><br>OBJECTIVES: This endeavor aims to evaluate the safety of 2,2'-Bipyridine (2,2'-Bipy) derivatives and their antimicrobial, anti-biofilm, and anti-persister activities in treating MRSA Infections.<br><br>METHODS: Six derivatives were screened for their ADMET properties and tested for minimum inhibitory concentrations against various bacterial strains using agar well diffusion and broth dilution. Safety studies were conducted through hemolysis tests, cell viability assays, and in vivo acute oral toxicity examinations. Bactericidal mechanisms and biofilm disruption effects were analyzed using crystal violet staining and confocal microscopy assays. The murine thigh infection model was also used to investigate the in vivo efficacy.<br><br>RESULTS: All derivatives exhibited favorable physicochemical profiles and ADMET properties and are predicted to be safe based on their drug-like properties. in vitro studies demonstrated that derivatives are non-toxic to 3T3 L1, and in vivo studies confirmed their safety in mice at a dose of 300 mg/kg and their non-hemolytic nature against rabbit red blood cells. All compounds showed potent antibacterial activity against the tested bacteria, including the resistant MRSA strain 831. They inhibited biofilm formation and eradicated biofilms in a dose-dependent manner against MTCC 737 and MRSA 831, and they effectively eliminated MRSA persister cells, outperforming the reference antibiotic vancomycin. These derivatives were found to depolarize the mitochondrial membrane and accumulate intracellular reactive oxygen species. These derivatives significantly reduced the bacterial load in the murine thigh infection model.<br><br>CONCLUSION: The study concluded that 2,2'-Bipy derivatives possess significant antimicrobial activity, are non-toxic, and are effective in inhibiting biofilm formation and killing persister cells.}, }
@article {pmid39924922, year = {2025}, author = {Ge, X and Deng, S and Chen, L and Feng, F and Fang, T and Ding, Y and Jiang, H and Yang, J and Liu, X and Dai, J and Yang, L and Ju, Y}, title = {Nano Copper-chelate Triggers Cuproptosis-like Death in Fungi and Synergizes with Microneedles for Enhanced Biofilm Removal.}, journal = {Advanced healthcare materials}, volume = {}, number = {}, pages = {e2404464}, doi = {10.1002/adhm.202404464}, pmid = {39924922}, issn = {2192-2659}, support = {2632024ZD07//The Fundamental Research Funds for the Central Universities/ ; 2632024TD02//The Fundamental Research Funds for the Central Universities/ ; TC2023B001//The Open Project of Jiangsu Provincial Science and Technology Resources (Clinical Resource) Coordination Service Platform/ ; 2022MK158//The Science and Technology Project of State Administration for Market Regulation/ ; }, abstract = {Fungal infections pose a significant global public health threat, particularly candidemia and biofilm formation. Current antifungal drugs have limitations due to their toxicity and drug resistance. Ion interference therapy, particularly cuproptosis, shows significant potential for disease treatment. Herein, nano copper-chelate Cu(DDC)2@BSA (CDB) is synthesized for antifungal research and the mechanism of cuproptosis-like death is investigated. Initially, CDB demonstrates a strong inhibitory effect on multiple fungi and exhibits strong antifungal activity against two fluconazole-resistant clinical isolates. The decrease in ATPase activity and mitochondrial membrane potential indicates that the antifungal mechanism may involve mitochondrial dysfunction. Subsequently, transcriptome analysis reveals significant alterations in genes related to copper ions transport and regulation, oxidative phosphorylation, and mitochondrial function. Additionally, copper ions overload is observed, along with an increase in heat shock protein 70 levels and a decrease in lipoic acid synthetase protein expression. Given that biofilms hinder drug penetration, quaternary ammonium chitosan microneedles are employed in combination with CDB to penetrate the biofilm barrier and enhance the antifungal effect. Overall, this study provides new insight into the cuproptosis-like death mechanism in fungi and presents a promising strategy for fungal infection treatment through the combination of nano copper-chelate and microneedle delivery system.}, }
@article {pmid39923528, year = {2025}, author = {Hu, Q and Hong, M and Wang, Z and Lin, X and Wang, W and Zheng, W and Zhou, S}, title = {Microbial biofilm-based hydrovoltaic pressure sensor with ultrahigh sensitivity for self-powered flexible electronics.}, journal = {Biosensors &amp; bioelectronics}, volume = {275}, number = {}, pages = {117220}, doi = {10.1016/j.bios.2025.117220}, pmid = {39923528}, issn = {1873-4235}, abstract = {Developing the integration of self-powered detection with both dynamic and static forces is a significant challenge in promoting intelligent technology systems. Herein, we introduce an innovative microbial biofilm based-hydrovoltaic pressure sensor (mBio-HPS) using whole-cell Geobacter sulfurreducens, which successfully combines self-powered functionality and static pressure detection within a single device. The mBio-HPS exhibited a sensitivity of up to 8968.7 kPa[-][1] (at 1 kPa) in the 0.4-25 kPa regime without external power supply. Moreover, the mBio-HPS demonstrated the fastest reported response speed to date, with a remarkable response time of 112.5 μs, enabling effective detection of both dynamic and static forces while maintaining stability during an extensive 30,000 s testing. Experimental validation using a sensor-integrated array showed its outstanding real-time detection capabilities for both dynamic and static pressure, highlighting its outstanding potential for electronic skin applications. This unprecedented concept of a hydrovoltaic pressure sensor also offers new insights into the development of high-performance self-powered electronics.}, }
@article {pmid39923370, year = {2025}, author = {Leopold, M and Kolm, C and Linke, RB and Schachner-Groehs, I and Koller, M and Kandler, W and Kittinger, C and Zarfel, G and Farnleitner, AH and Kirschner, AKT}, title = {Using a harmonised study design and quantitative tool-box reveals major inconsistencies when investigating the main drivers of water and biofilm antibiotic resistomes in different rivers.}, journal = {Journal of hazardous materials}, volume = {488}, number = {}, pages = {137343}, doi = {10.1016/j.jhazmat.2025.137343}, pmid = {39923370}, issn = {1873-3336}, abstract = {The spread of antibiotic resistance (ABR) via surface waters is of increasing concern. Large-scale studies investigating ABR drivers in different water bodies and habitats with uniform quantitative methods are largely missing. Here, we present a comprehensive investigation on ABR occurrence and drivers in water and biofilms of four Austrian rivers over a one-year-cycle using a harmonised quantitative tool-box and study-design. At the bacterial community level, human faecal pollution was a main factor driving the aquatic riverine resistome. Despite relatively low concentrations, also antibiotics and metals showed significant correlations, however to a different extent in the different rivers. At the organismic level, a decoupling of the Escherichia coli resistome from the bacterial community resistomes was observed. In biofilms, the relationships with anthropogenic pollution factors were heterogeneous and markedly dampened. Our results clearly show that general conclusions about the role of biofilms, the influence of pollution or the prevalence of resistance genes or phenotypic resistances must be drawn with caution. Results are dependent on the river and local situation of the sampling sites due to the large environmental heterogeneity. International harmonisation of the methodology and general awareness of this problem shall contribute to better understand environmental ABR to develop effective mitigation strategies.}, }
@article {pmid39923351, year = {2025}, author = {Tuytschaever, T and Raes, K and Sampers, I}, title = {Biofilm detection in the food industry: Challenges in identifying biofilm eps markers and analytical techniques with insights for Listeria monocytogenes.}, journal = {International journal of food microbiology}, volume = {432}, number = {}, pages = {111091}, doi = {10.1016/j.ijfoodmicro.2025.111091}, pmid = {39923351}, issn = {1879-3460}, abstract = {Extracellular polymeric substances (EPS) in biofilms are promising targets for eradicating biofilms and monitoring their presence, especially in the food industry. For this understanding, the composition of the EPS matrix is crucial. Ideally, a biofilm marker is found serving both purposes, but such a compound has not yet been discovered. This review aims to identify general biofilm EPS markers distinct from planktonic cells, focusing on macromolecules in the EPS matrix. It also evaluates the feasibility of this goal across different bacterial groups and environmental conditions and discusses EPS analysis methods. This review digs deeper into the EPS matrix starting with an introduction to the EPS matrix itself and describing some of its influencing factors. Next, a brief description of cell-to-cell communication within biofilms is provided, as these interactions significantly influence the EPS matrix. The main part of this review describes the macromolecules inside the EPS matrix and attempts to find biofilm EPS markers applied to bacteria in general and specifically to Listeria monocytogenes as biofilms are a major contributor to its persistence. The last part of the review focuses on the analytical techniques available to characterize the EPS matrix. The review revealed that although multiple candidates showed great potential as biofilm markers, none were unique but ubiquitous in all bacteria tested. To achieve easy biofilm detection with current techniques, it's necessary to identify markers specific to the environmental conditions and common bacterial groups within each food category, sector, or facility, due to the lack of standardization in these techniques. This tailored approach ensures more accurate and effective biofilm monitoring. Moreover, the lack of standardized analytical techniques, including quantification techniques, complexifies studying the EPS matrix and developing monitoring and intervention strategies. Optimizing analytical techniques is crucial for this tailored approach, as it requires refined methods for detection, characterization, and quantification. This ensures the accurate identification of biofilm markers specific to environmental conditions and bacterial groups within each food sector.}, }
@article {pmid39923153, year = {2024}, author = {Atiyah Ghafil, J and Khadhem Al-Sudani, SF and Salih Ibrahim, BM and Alshahrani, AM and Khadem Zgair, A}, title = {Relationship between biofilm formation of Pseudomonas aeruginosa and susceptibility to rifaximin and ofloxacin.}, journal = {Pakistan journal of pharmaceutical sciences}, volume = {37}, number = {6}, pages = {1609-1614}, pmid = {39923153}, issn = {1011-601X}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Pseudomonas aeruginosa/drug effects ; *Rifaximin/pharmacology ; *Ofloxacin/pharmacology ; *Anti-Bacterial Agents/pharmacology ; Humans ; *Microbial Sensitivity Tests ; Pseudomonas Infections/microbiology/drug therapy ; Urinary Tract Infections/microbiology/drug therapy ; Drug Resistance, Bacterial/drug effects ; }, abstract = {Pseudomonas aeruginosa is responsible for many infectious diseases related to antibiotic resistance. Biofilm formation may help bacteria to pass the treatment with antibiotics and overcome the immune system. Here, the relationship between antibiotics (rifaximin and ofloxacin) susceptibility and biofilm formation was evaluated. Ten isolates of P. aeruginosa were isolated from 110 urine specimens obtained from urinary tract infections (UTIs) patients. The spectrophotometric method was used to measure biofilm formation on polystyrene microtiter plates. Inhibitory zone onto agar plates was used to measure the antibiotic susceptibility of rifaximin and ofloxacin against the ten P. aeruginosa (Pa1, Pa2, Pa3, Pa15, Pa18, Pa22, Pa23, Pa25, Pa26 and Pa27) isolates. The highest inhibition zones were seen against Pa 25 and Pa 3 respectively, while the lowest inhibition zones of rifaximin were seen against Pa3, Pa23 and Pa25. Moreover, the lowest inhibition zones of both antibiotics were seen in the cases of Pa1 and Pa27 respectively. The maximum biofilm formation was seen in the case of Pa3, while Pa27 produced the lowest biofilm. The study showed no relationship between biofilm formation and susceptibility to rifaximin and ofloxacin (P>0.05).}, }
@article {pmid39920900, year = {2025}, author = {Murgia, C and Yazdi, Z and Soto, E}, title = {Susceptibility of Non-Tuberculous Mycobacteria Biofilm to Common Disinfectants in Aquaculture Systems.}, journal = {Journal of fish diseases}, volume = {}, number = {}, pages = {e14091}, doi = {10.1111/jfd.14091}, pmid = {39920900}, issn = {1365-2761}, support = {//Universit&#xe0; degli Studi di Sassari/ ; //School of Veterinary Medicine, University of California, Davis/ ; }, abstract = {Mycobacteriosis is a common and persistent bacterial disease affecting cultured, wild and pet fish. The disease can be caused by various Mycobacterium spp. Currently, depopulation and disinfection are the main recommended measures for containing disease outbreaks, as no vaccines are commercially available, and only a few reports of successful antimicrobial therapies have been made. While disinfectant susceptibility studies have been conducted on planktonic forms of some non-tuberculous mycobacteria (NTM) affecting fish, biofilm-related research remains limited. In this study, biofilm formation of Mycobacterium chelonae, Mycobacterium salmoniphilum, Mycobacterium arcueilense and Mycobacterium marinum isolates recovered from diseased fish were initially evaluated using the minimal biofilm eradication concentration (MBEC) assay system. All Mycobacterium spp. were able to form biofilms within a 2-week period when incubated at 25°C, but M. chelonae, M. salmoniphilum and M. arcueilense produced a faster and greater biofilm than M. marinum. To investigate the susceptibility of mycobacterial biofilms to common disinfectants, mature biofilms were divided into six treatment groups based on disinfectant type and exposure time: povidone-iodine (50 mg L[-1] free iodine) and bleach (200 mg L[-1] free chlorine) were applied for 30 min each; hydrogen peroxide (3% H2O2) and Virkon Aquatic (10 g L[-1]) were applied for 15 min each; and 70% ethanol was tested at both 15 and 30 min. Results demonstrated variable susceptibility among species. M. marinum was susceptible to all disinfectants, while M. arcueilense was susceptible to bleach, povidone-iodine and 70% ethanol (30-min exposure). None of the tested disinfectants at recommended doses effectively eradicated M. chelonae or M. salmoniphilum biofilms. These findings underscore species-specific differences in biofilm formation and resistance, emphasising the critical need for robust disinfection protocols in aquaculture settings to prevent mycobacteriosis transmission. Further research is essential to understand the mechanisms underlying disinfectant resistance among NTMs, optimise disinfection strategies and ensure the health and biosecurity of aquaculture facilities.}, }
@article {pmid39919951, year = {2025}, author = {Jurcisek, JA and Kurbatfinski, N and Wilbanks, KQ and Rhodes, JD and Goodman, SD and Bakaletz, LO}, title = {Mycobacterium abscessus biofilm cleared from murine lung by monoclonal antibody against bacterial DNABII proteins.}, journal = {Journal of cystic fibrosis : official journal of the European Cystic Fibrosis Society}, volume = {}, number = {}, pages = {}, doi = {10.1016/j.jcf.2025.01.013}, pmid = {39919951}, issn = {1873-5010}, abstract = {BACKGROUND: Pulmonary infections with multidrug-resistant nontuberculous mycobacteria (NTM), particularly Mycobacterium abscessus (MAB), are increasingly more prevalent in individuals with lung disease such as cystic fibrosis and are extremely difficult to treat. Protracted antibiotic therapies consist of multidrug regimens that last for months to years. Despite these intense protocols, failure rates are high with 50%-60% of patients not achieving a sustained culture-negative status. A major contributor to the difficult medical management of NTM infections is formation of pulmonary aggregate MAB biofilms which protect the resident bacteria from antimicrobials and host immune effectors. Thereby, novel and more effective approaches to combat recalcitrant NTM infections are urgently needed.<br><br>METHODS: We developed an epitope-targeted monoclonal antibody-based technology to rapidly disrupt biofilms and release resident bacteria into a transient yet highly vulnerable phenotype that is significantly more sensitive to killing by both antibiotics and host innate immune effectors (e.g., PMNs and antimicrobial peptides). Herein, we tested this technology in a pre-clinical murine lung infection model to determine whether this treatment would mediate clearance of MAB from the lungs and speed return to homeostasis.<br><br>RESULTS: As early as 48 h after a single treatment, bacterial loads were reduced to below the level of detection and histopathologic analysis showed markedly decreased inflammation and rapid eradication of aggregate biofilms compared to controls.<br><br>CONCLUSIONS: These new data add to those from multiple prior published studies which show the significant efficacy of this novel therapeutic approach to resolve recalcitrant bacterial biofilm diseases, now potentially including those induced by NTM.}, }
@article {pmid39919762, year = {2025}, author = {Rajab, AAH and Khafagy, ES and Lila, ASA and Yousef, N and Askoura, M}, title = {Combating enteropathogenic and multidrug resistant Escherichia coli using the lytic bacteriophage vB_EcoM_ECO78 which disrupts bacterial biofilm formation and exhibits a remarkable environmental stability.}, journal = {Journal of applied microbiology}, volume = {}, number = {}, pages = {}, doi = {10.1093/jambio/lxaf028}, pmid = {39919762}, issn = {1365-2672}, abstract = {AIM: The current study aimed to establish a phenotypic and genotypic characterization record of a novel lytic bacteriophage (phage) against multidrug-resistant (MDR) Escherichia coli (E. coli) infections.<br><br>METHODS AND RESULTS: Phenotypic characterization of the isolated phage included the assessment of phage morphology, host range, stability, and antibiofilm activity. The isolated phage vB_EcoM_ECO78 demonstrated high lytic activity against MDR E. coli and E. coli serotypes O78:K80:H12 and O26:H11. Additionally, it showed a marked antibiofilm activity and high physical stability at a wide range of temperatures and pH. Genotypic investigations identified a double-stranded DNA genome of 165 912 base pairs (bp) spanning 258 open reading frames (ORFs), out of which 149 ORFs were identified and annotated. In vivo analysis further confirmed the therapeutic potential of vB_EcoM_ECO78 which effectively increased the survival of mice infected with MDR E. coli.<br><br>CONCLUSION: The isolated phage vB_EcoM_ECO78 exhibits considerable stability and antibiofilm activity against MDR E. coli isolates, supported by notable environmental fitness and in vivo antibacterial capability.}, }
@article {pmid39919435, year = {2025}, author = {Bilal, H and Zhang, CX and Choudhary, MI and Dej-Adisai, S and Liu, Y and Chen, ZF}, title = {Copper(II) carboxylate complexes inhibit Staphylococcus aureus biofilm formation by targeting extracellular proteins.}, journal = {Journal of inorganic biochemistry}, volume = {266}, number = {}, pages = {112835}, doi = {10.1016/j.jinorgbio.2025.112835}, pmid = {39919435}, issn = {1873-3344}, abstract = {Three copper(II) complexes of diphenyl acetic acid (DPAA) pyridine (py), 2,2΄-dipyridylamine (dpa), and 4,7-diphenyl, 1,10-phenanthrline (di-phen), [Cu2(DPAA)4(py)2] (Cu-1), [Cu(DPAA)2(dpa)] (Cu-2), and [Cu2(DPAA)4(di-phen)2] (Cu-3) were synthesized and characterized. Their antibacterial activities were evalvated. The minimum inhibitory concentrations (MIC) of these complexes against six tested microbial strains ranged from 1 to 128 μg/mL, and that of vancomycin antibiotic ranged from 0.5 to 2 μg/mL. The bactericidal effects of Cu-1, Cu-2 and Cu-3 and vancomycin against Staphylococcus aureus (S. aureus) were determined by colony count assay. Cu-1, Cu-2, and vancomycin showed relatively weaker antibiofilm formation activities; however, Cu-3 showed enhanced activity against S. aureus proliferation and biofilm formation as confirmed by microscopic analysis. In antibiofilm assays, Cu-1, Cu-2 and Cu-3 demonstrated high inhibition ability (23-75 %), of mature biofilm formation at concentrations of 5 to 15 μg/mL, and vancomycin at 15 μg/mL inhibited only 47 %. Cu-3 also effectively killed S. aureus within biofilms at doses up to 2 × MIC μg/mL. Further analysis of extracellular proteins (ECPs) expression revealed, that Cu-3 had significant potential in suppressing ECPs production. Molecular docking (MD) studies with biofilm associated protein (Bap) and SARS-CoV-2 receptors showed high interactions by several bonding types, where Cu-2 found as potent antiviral agent. Collectively, these findings highlighted the copper complexes potential in antibacterial applications, with Cu-3 emerging as a potent candidate for S. aureus biofilm inhibition.}, }
@article {pmid39919096, year = {2025}, author = {Carlew, TS and Brenya, E and Ferdous, M and Banerjee, I and Donnelly, L and Heinze, E and King, J and Sexton, B and Lacey, RF and Bakshi, A and Alexandre, G and Binder, BM}, title = {Ethylene signals through an ethylene receptor to modulate biofilm formation and root colonization in a beneficial plant-associated bacterium.}, journal = {PLoS genetics}, volume = {21}, number = {2}, pages = {e1011587}, pmid = {39919096}, issn = {1553-7404}, mesh = {*Ethylenes/metabolism ; *Biofilms/growth &amp; development ; *Plant Roots/microbiology/growth &amp; development ; *Receptors, Cell Surface/metabolism/genetics ; *Azospirillum brasilense/metabolism/genetics ; Signal Transduction ; Plant Growth Regulators/metabolism ; Bacterial Proteins/metabolism/genetics ; }, abstract = {Ethylene is a plant hormone involved in many aspects of plant growth and development as well as responses to stress. The role of ethylene in plant-microbe interactions has been explored from the perspective of plants. However, only a small number of studies have examined the role of ethylene in microbes. We demonstrated that Azospirillum brasilense contains a functional ethylene receptor that we call Azospirillum Ethylene Response1 (AzoEtr1) after the nomenclature used in plants. AzoEtr1 directly binds ethylene with high affinity. Treating cells with ethylene or disrupting the receptor reduces biofilm formation and colonization of plant root surfaces. Additionally, RNA sequencing and untargeted metabolomics showed that ethylene causes wide-spread metabolic changes that affect carbon and nitrogen metabolism. One result is the accumulation of poly-hydroxybutyrate. Our data suggests a model in which ethylene from host plants alters the density of colonization by A. brasilense and re-wires its metabolism, suggesting that the bacterium implements an adaptation program upon sensing ethylene. These data provide potential new targets to regulate beneficial plant-microbe interactions.}, }
@article {pmid39918987, year = {2025}, author = {Bagchi, S and Sharma, AK and Mal, S and Kundu, M and Basu, J}, title = {Crosstalk between cyclic-di-guanosine monophosphate and the sensor kinase MtrB regulates MtrA-dependent genes, bacterial growth, biofilm formation and lysosomal trafficking of Mycobacterium tuberculosis.}, journal = {Microbiology (Reading, England)}, volume = {171}, number = {2}, pages = {}, doi = {10.1099/mic.0.001532}, pmid = {39918987}, issn = {1465-2080}, mesh = {*Mycobacterium tuberculosis/genetics/metabolism/growth &amp; development ; *Bacterial Proteins/metabolism/genetics ; *Biofilms/growth &amp; development ; *Gene Expression Regulation, Bacterial ; *Cyclic GMP/metabolism/analogs &amp; derivatives ; Lysosomes/metabolism ; Phosphorylation ; Macrophages/microbiology ; Regulon ; Humans ; Transcription Factors ; RNA-Binding Proteins ; ATP-Binding Cassette Transporters ; }, abstract = {Cyclic-di-guanosine monophosphate (c-di-GMP) plays an important role in bacterial signalling networks. C-di-GMP exerts a regulatory function through binding to diverse molecules that include transcription factors, riboswitches and sensor kinases (SKs), thereby regulating diverse processes. Here, we demonstrate the crosstalk between c-di-GMP and the SK MtrB of Mycobacterium tuberculosis. MtrB phosphorylates and regulates its cognate response regulator MtrA. C-di-GMP binds directly to the cytosolic domain of MtrB to inhibit its autophosphorylation. C-di-GMP levels in M. tuberculosis were manipulated by overexpressing a c-di-GMP synthesizing enzyme ydeH and a degrading enzyme rv1357c. We demonstrate that overexpression of ydeH lowers growth of the bacterium both in vitro and in M. tuberculosis grown in macrophages. This is in conformity with lowered expression of mtrA and selected genes of the mtrA regulon involved in cell wall turnover in the ydeH-overexpressing strain compared to the parent strain. We also demonstrate that overexpression of ydeH in M. tuberculosis hinders biofilm formation, whereas overexpression of rv1357c has the opposite effect. Neither of the two genes could rescue the biofilm defective phenotype of the MtrB knock out mutant (ΔmtrB), suggesting that c-di-GMP exerts its role on biofilm formation through MtrB. Finally, we show by fluorescence microscopy that the trafficking of M. tuberculosis overexpressing ydeH is significantly higher than that of the parent strain and that this is linked to reduced expression of the MtrB-dependent genes esxG and esxH, which play a role in subversion of lysosomal trafficking of M. tuberculosis. These results provide important new insight into the crosstalk between c-di-GMP and MtrB in M. tuberculosis.}, }
@article {pmid39918333, year = {2025}, author = {Molaeitabari, A and Dahms, TES}, title = {Blocking the shikimate pathway amplifies the impact of carvacrol on biofilm formation in Candida albicans.}, journal = {Microbiology spectrum}, volume = {}, number = {}, pages = {e0275424}, doi = {10.1128/spectrum.02754-24}, pmid = {39918333}, issn = {2165-0497}, abstract = {Candida albicans typically thrives in a commensal relationship with humans but is also an opportunistic fungal pathogen. As an opportunistic pathogen, C. albicans relies heavily on its ability to assimilate nutrients, for which it must compete with the host and other microorganisms. Amino acid biosynthesis, sensing, and uptake play pivotal roles in C. albicans growth and pathogenicity. C. albicans biosynthesizes aromatic amino acids and co-enzyme Q de novo through the shikimate pathway, including the Aro1, Aro2, and Aro7 enzymes, but also has amino acid transporters for uptake from the environment. Thus, antifungal approaches targeting aromatic amino acid biosynthesis must simultaneously inhibit amino acid biosynthesis and uptake. Herein, we investigate the plant-based antifungal, carvacrol, in conjunction with aromatic amino acid biosynthetic mutants, as a potential anti-candidal strategy. Growth of the WT, ARO2, and ARO7 strains were inhibited by 150 µg/mL carvacrol, whereas the ARO1 mutant was slightly more sensitive (with MIC 125 µg/mL). All repressed mutants exposed to carvacrol are partially rescued in the presence of para-aminobenzoic acid (PABA) (CoQ precursor), indicating that blocking the shikimate pathway impacts both aromatic amino acid and CoQ biosynthesis. Moreover, carvacrol at sublethal concentrations significantly inhibits ARO1 adhesion and hyphal formation, along with pre-attached and pre-formed hyphae, ultimately impacting biofilm metabolic activity and biomass accumulation and significantly reducing biofilm growth. In summary, carvacrol increases the sensitivity of C. albicans to ARO1 repression, with attenuated adhesion, hyphal formation, mycelial growth and biofilm formation, likely by blocking aromatic amino acid uptake.IMPORTANCEThe opportunistic pathogen Candida albicans remains the leading cause of candidemia and invasive candidiasis (IC), causing significant morbidity and mortality in immunocompromised patients. Our current arsenal of effective antifungal drugs is limited in number, mechanistic diversity, and efficacy, are cytotoxic and associated with antifungal resistance, necessitating the development of novel antifungals and combination therapies. Here, we show how simultaneously blocking the shikimate pathway, through ARO1 repression, and disrupting aromatic amino acid uptake by carvacrol prevent C. albicans biofilm formation. Thus, inhibitors of the Aro1 enzyme in combination with carvacrol are expected to shut down C. albicans biofilm formation and virulence.}, }
@article {pmid39918303, year = {2025}, author = {Xie, Y and Liu, H and Teng, Z and Ma, J and Liu, G}, title = {Nanomaterial-enabled anti-biofilm strategies: new opportunities for treatment of bacterial infections.}, journal = {Nanoscale}, volume = {}, number = {}, pages = {}, doi = {10.1039/d4nr04774e}, pmid = {39918303}, issn = {2040-3372}, abstract = {Biofilms play a pivotal role in bacterial pathogenicity and antibiotic resistance, representing a major challenge in the treatment of bacterial infections. The limited diffusion and inactivation efficacy of antibiotics within biofilms hinder their clearance, and while increasing dosage may enhance effectiveness, it also promotes antibiotic resistance. Nano-delivery systems that target antimicrobial agents directly to biofilms offer a promising strategy to overcome this challenge. This review summarizes the resistance mechanisms and therapeutic challenges associated with biofilms, with a focus on recent advances in nano-delivery systems such as liposomes, nanoemulsions, cell membrane vesicles (CMVs), polymers, dendrimers, nanogels, inorganic nanoparticles, and metal-organic frameworks (MOFs). Furthermore, the review explores the potential applications and challenges of nano-delivery systems in biofilm treatment and provides recommendations to guide future research and development in this field.}, }
@article {pmid39916977, year = {2025}, author = {Anitua, E and Murias-Freijo, A and Tierno, R and Tejero, R and Hamdan Alkhraisat, M}, title = {Effect of implant abutment surface treatments on bacterial biofilm composition and structure.}, journal = {Journal of oral microbiology}, volume = {17}, number = {1}, pages = {2459922}, pmid = {39916977}, issn = {2000-2297}, abstract = {BACKGROUND: For the long-term success of dental implants, implant abutment surface should promote the attachment of oral epithelial cells and reduce bacterial adhesion. Titanium nitride (TiN) coatings show antimicrobial properties. Nevertheless, there is a lack of clinical trials that assess the biofilm formation on TiN abutments in the context of clinical practice. Thus, the objective of this study was to evaluate the effect of different abutment surfaces (machined, TiN and TiN oxidized) on bacterial biofilm composition and structure.<br><br>MATERIALS AND METHODS: Implant abutments were connected to the dental implants. Bacterial communities were sampled at 1 and 60&#x2009;days later. The relationship between surface, periodontal indices and bacterial community dynamics was assessed using 16S rRNA metagenomics. A total of 17 patients were involved in this study (14 included in final analyses: 15 machined, 16 TiN and 14 TiN oxidized abutments).<br><br>RESULTS: No significant differences between surfaces were found considering taxa abundance, most alpha diversity metrics or community structure. Time showed a significant effect on diversity and also on the abundance of several bacterial taxa.<br><br>CONCLUSIONS: These results indicate that the effect of the three tested abutment surfaces on biofilm structure and composition was negligible, whereas patient and time exert strong influences on bacterial biofilm formation at different scales.}, }
@article {pmid39914576, year = {2025}, author = {Awad, EH and Arafa, W and Ali, HR and Barakat, OS and Ahmed, MN}, title = {Unveiling the anti-biofilm potential of bee venom against multi-drug resistant human pathogenic bacteria and fungi: perspectives into the efficacy and Possible mechanisms.}, journal = {Microbial pathogenesis}, volume = {200}, number = {}, pages = {107358}, doi = {10.1016/j.micpath.2025.107358}, pmid = {39914576}, issn = {1096-1208}, abstract = {Bacterial biofilms pose significant challenges in treating infectious diseases due to antibiotic resistance. Finding alternative natural antimicrobial agents is crucial. Bee products, long valued for their nutritional and therapeutic benefits, exhibit potent antibacterial properties. This study investigates bee venom's antibacterial activity against biofilms formed by isolated microorganisms. Biofilm formation of pathogenic bacteria and yeast isolated from cannula was studied using two models: 96-well plates and alginate beads. We showed that low doses of bee venom effectively combat biofilms of bacterial and yeast strains. Antibiofilm assays employed in this study revealed the efficacy of bee venom against biofilms formed by multi-drug resistant Staphylococcus aureus, Pseudomonas aeruginosa and Canndida species isolates. We investigated the potential of bee venom to specifically target pathogenic bacteria while sparing commensal bacteria, showing minimal effects on the commensal bacteria tested in this study. The cytotoxicity of bee venom was evaluated on normal human fibroblast cells (HFB4), revealing a half maximal inhibitory concentration (IC50) of 7 mg/mL, which is substantially higher than the effective antibiofilm dose (0.5 μg/mL) used against pathogenic bacteria and yeast strains tested in this study. Gene expression analysis further indicated that bee venom treatment influences genes associated with biofilm formation, specifically icaA and icaD in Staphylococcus aureus, as well as genes related to efflux pump activity, including nfxB, which contribute to biofilm persistence in Pseudomonas aeruginosa. Additionally, we employed electron microscopy imaging of single cells and biofilms treated with bee venom to visualize the effects of bee venom. Furthermore, Molecular docking studies employed in this study demonstrate exclusively that bee venom components bind efficiently to antibiotic-resistant determinants, virulence factors, and quorum sensing regulators in the isolated pathogenic bacteria and yeasts, highlighting the need of further explorations into in vivo effects and underlying mechanisms.}, }
@article {pmid39914517, year = {2025}, author = {Ionescu, AC and Nicita, F and Zambelli, V and Bellani, G and Degli Esposti, L and Iafisco, M and Brambilla, E}, title = {Ion-releasing resin composites prevent demineralization around restorations in an in-vitro biofilm model.}, journal = {Journal of dentistry}, volume = {154}, number = {}, pages = {105600}, doi = {10.1016/j.jdent.2025.105600}, pmid = {39914517}, issn = {1879-176X}, abstract = {OBJECTIVE: This study aimed to evaluate the effectiveness of two ion-releasing, resin-based composites (RBCs), ACTIVA BioACTIVE-Restorative (BIO1) and ACTIVA Presto (BIO2), in preventing demineralization around restorations.<br><br>METHODS: Class I and II cavities were prepared on bovine (n = 4) and human teeth (n = 8) and restored with BIO1, BIO2, a conventional composite (RBC, Filtek Supreme XTE), and a resin-modified glass ionomer cement (RMGIC, Ionolux). Following restorations (class I, n= 16/material; class II, n= 8/material), the specimens were exposed to Streptococcus mutans biofilm in a continuous-flow bioreactor over two weeks. Micro-computed tomography (micro-CT) assessed demineralization depths at restoration margins, and supernatant pH changes were measured after a 24-h acidic challenge. Statistical analyses included one and two-way ANOVA and Tukey's test (p < 0.05).<br><br>RESULTS: On enamel surfaces, RMGIC showed no demineralization, followed by BIO1 (&#x2248;50 &#x3bc;m), BIO2 (&#x2248;125 &#x3bc;m), and RBC (&#x2248;150 &#x3bc;m). No difference between human or bovine enamel was observed. In dentin, RMGIC showed the least demineralization (&#x2248;190 &#x3bc;m), followed by BIO1 (&#x2248;230 &#x3bc;m), BIO2 (&#x2248;280 &#x3bc;m), and RBC (&#x2248;400 &#x3bc;m). pH buffering was highest in RMGIC (+ 0.24 pH), while BIO1, BIO2, and RBC showed similar buffering capacities (&#x223c; +0.1 pH). Gaps were found at several interfaces for BIO1 and RMGIC.<br><br>CONCLUSIONS: Ion-releasing RBCs varied in effectiveness for reducing demineralization of surrounding tissues, with limited pH buffering capacity. RMGIC exhibited better performance. Gaps between cavity walls and BIO1/RMGIC raised concerns about long-term adhesion.<br><br>CLINICAL SIGNIFICANCE: ACTIVA BioACTIVE Restorative (BIO1) and ACTIVA Presto (BIO2) resin-based composites promoted slight inhibition of demineralization in an in-vitro biofilm model, suggesting that further modifications in their chemical composition are necessary.}, }
@article {pmid39914332, year = {2025}, author = {Rossi, M and Vergara, A and Troisi, R and Alberico, M and Carraturo, F and Salamone, M and Giordano, S and Capozzi, F and Spagnuolo, V and de Magistris, FA and Donadio, C and Scognamiglio, V and Vedi, V and Guida, M}, title = {Microplastics, microfibers and associated microbiota biofilm analysis in seawater, a case study from the Vesuvian Coast, southern Italy.}, journal = {Journal of hazardous materials}, volume = {488}, number = {}, pages = {137468}, doi = {10.1016/j.jhazmat.2025.137468}, pmid = {39914332}, issn = {1873-3336}, abstract = {The growing concerns regarding pollution from microplastics (MPs) and microfibers (MFs) have driven the scientific community to develop new solutions for monitoring ecosystems. However, many of the proposed technologies still include protocols for treating environmental samples that may alter plastic materials, leading to inaccurate results both in observation and in counting. For this reason, we are refining a protocol, based on optical microscopy without the use of pretreatments, applicable to different environmental matrices, which allows not only counting but also a complete morphological characterization of MPs and MFs. Previously, the protocol has successfully been tested on marine sediments from the Vesuvian area of the Gulf of Naples (Italy) with good results. In the present study, we tested the protocol on MPs and MFs in seawater samples collected from the same geographical area to provide a comprehensive overview of their distribution in the marine environments. The protocol enabled not only the morphological characterization of MPs and MFs but also the collection of information on the colonies of microorganisms present on the microparticles. Next Generation Sequencing (NGS) metagenomic technologies enabled us to characterize the microbiota composition of the sampled MPs, the so-called Plastisphere. The analytical approach allowed the characterization of several potentially pathogenic bacteria, which represent a potential threat to the environment and human health. In fact, they may exploit their ability to form biofilms on plastics to proliferate in marine ecosystems.}, }
@article {pmid39913171, year = {2025}, author = {Wang, Z and Li, B and Nie, C and Zhang, R and Qu, S and Shao, Q and Zhang, X and Li, J and Li, W and Li, H and Xiao, J and Xing, C}, title = {Photothermal Conjugated Polymer Microneedle with Biofilm Elimination and Angiogenesis for Diabetic Wound Healing.}, journal = {Nano letters}, volume = {}, number = {}, pages = {}, doi = {10.1021/acs.nanolett.4c06284}, pmid = {39913171}, issn = {1530-6992}, abstract = {Diabetic wounds are highly susceptible to bacterial infection, which can lead to the formation of bacterial biofilms, making diabetic wound healing a major challenge. In this study, a composited microneedle that incorporated drug-loaded conjugated polymer nanoparticles and basic fibroblast growth factor was prepared to eliminate biofilms and promote vascular regeneration. This microneedle released minocycline under near-infrared (NIR) light, effectively penetrating bacterial biofilms. The photothermal properties of the conjugated polymers, combined with the antibacterial action of minocycline, contribute to the eradication of biofilms and the elimination of drug-resistant bacteria. Moreover, it regulated the wound microenvironment by reducing the level of oxidative stress, as well as the production of inflammatory factors at the wound site. Meanwhile, it effectively boosted cell migration and promoted angiogenesis to accelerate diabetic wound healing. This composited microneedle for biofilm elimination represents a promising approach for promoting diabetic wound healing.}, }
@article {pmid39912145, year = {2025}, author = {Paul, NA and Bhat M, R and Antony, B and Jayaraman, J}, title = {Antibiotic resistance and biofilm formation in Cutibacterium acnes: A descriptive cross-sectional study.}, journal = {Indian journal of dermatology, venereology and leprology}, volume = {}, number = {}, pages = {1-6}, doi = {10.25259/IJDVL_539_2024}, pmid = {39912145}, issn = {0973-3922}, abstract = {Background The issue of antibiotic resistance in acne vulgaris has emerged as a significant concern in recent times. Though the ability of Cutibacterium acnes to form biofilms have been established, its role in acne vulgaris has yet to be ascertained. Aims This descriptive cross-sectional study was aimed to investigate the ability of C. acnes to form biofilms and its potential association with resistance to the commonly used antibiotics. Methods A total of 88 patients with acne vulgaris were selected for this study. Clinical examination and severity grading was done. The collected samples were analysed with Matrix-Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry (MALDI-TOF-MS) and further subjected to biofilm testing using the microtiter plate assay. Results C. acnes were isolated from 43.1 of the samples (n = 38). The highest resistance was observed with azithromycin (73.7%) followed by clindamycin (65.8%), doxycycline (15.8%), ampicillin (31.6%) and minocycline (5.3%). Thirty-seven per cent of the isolates were resistant to at least two antibiotics, 63.2% of C. acnes had a weak capacity to form biofilms and more than 60 percent of the isolates showed resistance to atleast two types of antibiotics as well as weak biofilm forming capacity. Limitations Single-centre study, small sample, long-term follow-up of the patients was not done. In addition, this study is representative of only C. acnes species. Conclusion While C. acnes have the ability to create biofilms, its effectiveness in antibiotic resistance can be deemed as modest based on the findings of this study. It is important to consider alternative mechanisms such as genetic or biochemical plasticity that may contribute to antibiotic resistance.}, }
@article {pmid39909925, year = {2025}, author = {Snega Priya, P and Meenatchi, R and Pasupuleti, M and Namasivayam, SKR and Arockiaraj, J}, title = {Harnessing Cyclic di-GMP Signaling: A Strategic Approach to Combat Bacterial Biofilm-Associated Chronic Infections.}, journal = {Current microbiology}, volume = {82}, number = {3}, pages = {118}, pmid = {39909925}, issn = {1432-0991}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Cyclic GMP/analogs &amp; derivatives/metabolism ; *Signal Transduction ; Humans ; Anti-Bacterial Agents/pharmacology ; Bacteria/metabolism/drug effects/genetics ; Bacterial Infections/drug therapy/microbiology ; Bacterial Proteins/metabolism/genetics ; Gene Expression Regulation, Bacterial ; Quorum Sensing/drug effects ; Persistent Infection/microbiology ; Virulence Factors/metabolism ; }, abstract = {Cyclic dimeric guanosine monophosphate (c-di-GMP) plays a vital role within the nucleotide signaling network of bacteria, participating in various biological processes such as biofilm formation and toxin production, among others. Substantial evidence demonstrates its critical involvement in the progression of chronic infections. Treating chronic infections seems critical, and there is a worldwide quest for drugs that target pathogens' unique and complex virulence-associated signaling networks. c-di-GMP is a promising therapeutic target by serving as a distinct virulence factor, solving problems associated with drug resistance, biofilm dispersion, and its related septicemia complications. c-di-GMP levels act as checkpoints for several biofilm-associated molecular pathways, viz., Gac/Rsm, BrlR, and SagS signaling systems. C-di-GMP is also engaged in the Wsp chemosensory pathway responsible for rugose small colony variants observed in cystic fibrosis-related lung infections. Considering all factors, c-di-GMP serves as a pivotal hub in the intricate cascade of biofilm regulation. By overseeing QS systems, exopolysaccharide synthesis, and antibiotic resistance pathways in chronic infections, it emerges as a linchpin for effective drug development strategies against biofilm-related ailments. This underscores the significance of understanding the multifaceted signaling networks. c-di-GMP's role is highlighted in this review as a concealed virulence component in various bacterial pathogens, suggesting that medications targeting it could hold promise in treating chronic disorders associated with biofilms.}, }
@article {pmid39909094, year = {2025}, author = {Guo, X and Zhu, W and Peng, G and Zhang, Y and Wang, J and Wang, Z and Tan, L and Zhang, S}, title = {Current intensity and hydraulic retention time play differential roles in functional gene expression or electron transfer pathways in a pyrite-filled three-dimensional biofilm electrode reactor (P3DBER).}, journal = {Environmental research}, volume = {270}, number = {}, pages = {121040}, doi = {10.1016/j.envres.2025.121040}, pmid = {39909094}, issn = {1096-0953}, abstract = {This study developed a pyrite-filled three-dimensional biofilm electrode reactor (P3DBER) to treat nitrate wastewater with a low carbon/nitrogen ratio. Meanwhile, the joint effect of current intensity (CI) and hydraulic retention time (HRT) on the performance of the P3DBER was investigated. Results indicated that under the optimal conditions (CI = 30 mA, HRT = 4.9 h), the total inorganic nitrogen removal efficiency (TINRE) reached a maximum of 93.5 ± 1.4%, with a low electrical consumption of 0.075 kW h/g TIN. Increasing CI under different HRTs significantly enhanced the nitrogen removal capacity of the P3DBER. However, at high CI (30 mA), prolonging HRT did not further improve the nitrogen removal efficiency. The introduction of pyrite not only increased the types of electron donors but also could effectively maintain the stability of pH in the P3DBER. Variation partitioning analysis (VPA) showed that CI had a greater impact on the microbial community/functional genes than HRT. In addition, network analysis demonstrated a strong interconnection among microorganisms/functional genes within the P3DBER. This study offers valuable information for optimizing the operating parameters of the P3DBER.}, }
@article {pmid39907142, year = {2025}, author = {Guimarães, CDRE and Galvão, DS and do Desterro Cunha, S and Fonseca de Freitas, H and Barros, TF}, title = {Thiosemicarbazones and analogues as potential biofilm inhibitors of Candida albicans.}, journal = {Biofouling}, volume = {41}, number = {2}, pages = {197-210}, doi = {10.1080/08927014.2025.2457151}, pmid = {39907142}, issn = {1029-2454}, mesh = {*Biofilms/drug effects ; *Candida albicans/drug effects/physiology ; *Antifungal Agents/pharmacology/chemistry ; *Thiosemicarbazones/pharmacology/chemistry ; Microbial Sensitivity Tests ; Hyphae/drug effects ; Microscopy, Electron, Scanning ; }, abstract = {Biofilms are a virulence factor for Candida albicans, a common pathogen in human fungal infections, making them resistant to many commercial antifungals. Therefore, the discovery of compounds that inhibit and eradicate biofilms is a priority. As thiosemicarbazones have had their effect on Candida biofilms little explored, this study investigated the inhibitory and eradication activity of 30 thiosemicarbazones and analogues against C. albicans biofilms. After initial screening, four compounds were selected and compound 28 emerged as the most potent with BIC50 at 31.55 ± 1.18 µM. By scanning electron microscopy analysis, blastoconidia adhered to the reduced surface and reduced formation of pseudohyphae and hyphae was revealed. Despite the inhibitory activity, the four compounds failed to eradicate the biofilm by more than 50%. Thus, the results suggest that the compounds evaluated are very promising for the development of effective antibiofilm compounds and open up new perspectives for elucidating the mechanism of action.}, }
@article {pmid39906988, year = {2025}, author = {Alacid, E and Reñé, A and Timoneda, N and Garcés, E}, title = {Macroalgal Biofilm Harbours a Wide Diversity of Parasitic Protists With Distinct Temporal Dynamics.}, journal = {Molecular ecology}, volume = {}, number = {}, pages = {e17666}, doi = {10.1111/mec.17666}, pmid = {39906988}, issn = {1365-294X}, support = {BP2020-00174//Beatriu de Pin&#xf3;s Postdoctoral Program/ ; PID2020-112978GB-I00//Spanish Ministry of Science, Innovation, and Universities (MICINN)/ ; }, abstract = {Marine macroalgae surfaces create a nutrient-rich environment that promotes the formation of epiphyte biofilms. Biofilms are complex systems that facilitate ecological interactions within the community, yet parasitism remains largely unexplored. This study describes the diversity and temporal dynamics of the microeukaryotic community in the biofilm of Mediterranean macroalgae during summer, focusing on parasitic groups. Protist diversity was assessed using metabarcoding sequencing of the V4 region of the 18S rDNA gene using primers biased against metazoans. The macroalgal biofilm exhibited dynamic shifts in the microeukaryotic community structure associated to three phases of biofilm formation. Each phase was characterised by the dominance of specific eukaryotic and parasitic groups with clear successions between them. Our study revealed a high diversity of parasitic protists from different lineages in the macroalgal biofilm. These parasites can infect a wide variety of hosts, including the basibiont, species within the biofilm (micro- and macrocolonizers), nearby marine hosts and terrestrial organisms. The highest diversity and abundance of parasites were found in the mature phase of the biofilm, where the complexity and stability of the system seem to favour parasitism. The parasite assemblage was dominated by Apicomplexa, with many corresponding to unknown diversity, demonstrating that biofilms are a hotspot of unknown parasitic interactions. These parasites could potentially affect the dynamics of these communities and facilitate ecological interactions between the biofilm and surrounding organisms, suggesting that parasitism play a key, but still unexplored role, in shaping complex marine biofilms network.}, }
@article {pmid39906281, year = {2025}, author = {Alizadeh Behbahani, B and Rahmati-Joneidabad, M and Taki, M}, title = {Examining the impact of probiotic Lactiplantibacillus pentosus 6MMI on inhibiting biofilm formation, adhesion, and virulence gene expression in Listeria monocytogenes ATCC 19115.}, journal = {Biofilm}, volume = {9}, number = {}, pages = {100255}, pmid = {39906281}, issn = {2590-2075}, abstract = {Probiotic bacteria improve human health by secreting pro-microbial substances, balancing intestinal flora, binding to the mucous membrane and epithelium, strengthening the intestinal epithelial barrier, and creating interactions between the gastrointestinal microbiota and the immune system. This study aimed to investigate the probiotic potential, biofilm-related gene expression and anti-biofilm capabilities of Lactiplantibacillus pentosus 6MMI. The strain exhibited remarkable resilience to challenging conditions, including acidic environments, gastrointestinal settings, and bile salts. Notably, Lpb. pentosus demonstrated significant hydrophobicity (71.89 %), auto-aggregation (42.39 %), co-aggregation (51.28 %), antioxidant activity (ranging from 42.29 % to 64.61 %), and a cholesterol reduction capacity of 50.31 %. Its competitive abilities against Listeria monocytogenes were quantified, showing a competition rate of 54.51 %, displacement rate of 48.57 %, and inhibition of adhesion at 27.71 %. Also, Lpb. pentosus resulted an adhesion rate of 12.91 % to epithelial cells and showed no DNase or hemolytic activity. The strain exhibited the highest resistance to nalidixic acid, with an inhibition zone measuring 15.20 mm, while it was least resistant to chloramphenicol, which had an inhibition zone of 27.30 mm. Treatment with cell-free supernatant (CFS) from Lpb. pentosus significantly reduced biofilm formation by 91.25 % and 24.50 % and diminished mature biofilm formation by 83.82 % and 21.80 % on L. monocytogenes. Additionally, the CFS inhibited the transcription of the plcB, hly, and prfA genes in L. monocytogenes, suggesting a potential reduction in bacterial virulence through decreased hemolysin release and modulation of phospholipase activity. In the next step of the study, the Gaussian Process Regression (GPR) model accurately predicted bile tolerance and acid parameters with a high R[2] of 0.99 and minimal Mean Absolute Percentage Error (MAPE) values of 0.33 % and 0.21 %, respectively. The residual errors showed a normal distribution, indicating reliable and consistent predictions. Overall, Lpb. pentosus 6MMI represents a valuable candidate for further investigation in probiotic development and biofilm management strategies.}, }
@article {pmid39905764, year = {2025}, author = {Erkan, MH and Boğa, M and Salih, H and Barbarus, E and Rahman, &#xd6;F and Sakarya, S}, title = {Effect of surface coatings on endothelialization and biofilm in PTFE vascular grafts.}, journal = {The International journal of artificial organs}, volume = {}, number = {}, pages = {3913988251316438}, doi = {10.1177/03913988251316438}, pmid = {39905764}, issn = {1724-6040}, abstract = {Polytetrafluoroethylene (PTFE) grafts are of great importance for vascular surgery and many methods have been developed to improve their biocompatibility. The most important of these methods is the coating of the inner surfaces of the grafts. In this study, the effects of surface coatings used in vascular grafts on endothelialization and bacterial biofilm formation were investigated. Three different PTFE graft types, heparin coated, carbon coated and uncoated, were compared. HUVEC cell culture was used for endothelialization experiments and Staphylococcus aureus strain was used for biofilm formation. Endothelialization was evaluated by inverted microscopy and scanning electron microscopy (SEM). Heparin-coated grafts showed more biofilm formation than other graft types (p < 0.01). Moderate biofilm formation was observed in carbon-coated grafts (p < 0.05). When evaluating endothelialization, heparin-coated grafts showed more cell adhesion in the first days, but lagged behind the other graft types in the following days. Carbon-coated grafts showed more endothelial cell proliferation in the long term. While biofilm formation was high in heparin-coated grafts, carbon-coated grafts provided better endothelialization. Our study showed that the coating of PTFE grafts significantly affects biocompatibility and infection risk.}, }
@article {pmid39905565, year = {2025}, author = {Gao, S and Yuan, S and Quan, Y and Jin, W and Shen, Y and Li, R and Liu, B and Wang, Y and Yi, L and Wang, S and Hou, X and Wang, Y}, title = {Targeting AI-2 quorum sensing: harnessing natural products against Streptococcus suis biofilm infection.}, journal = {Veterinary research}, volume = {56}, number = {1}, pages = {26}, pmid = {39905565}, issn = {1297-9716}, support = {32172852//National Natural Science Foundation of China/ ; 32172856//National Natural Science Foundation of China/ ; }, mesh = {*Quorum Sensing/drug effects ; *Biofilms/drug effects ; *Streptococcus suis/physiology/drug effects ; *Streptococcal Infections/veterinary/microbiology ; Biological Products/pharmacology ; Homoserine/analogs &amp; derivatives/metabolism ; Lactones/pharmacology/metabolism ; Animals ; Anti-Bacterial Agents/pharmacology ; }, abstract = {The biofilm acts as a protective layer for Streptococcus suis (S. suis), contributing to the development of drug resistance and chronic infections. Autoinducer 2 (AI-2) quorum sensing represents the primary regulatory pathway governing biofilm formation in S. suis. Consequently, targeting AI-2 quorum sensing to inhibit biofilm formation represents a promising strategy for preventing and managing drug resistance and chronic infections caused by S. suis. This study established a small natural product library by integrating commercial drug molecules with Chinese herbal medicine molecules. Consequently, two natural products, salvianolic acid A (SAA) and rhapontin (RH), which target S. suis AI-2 via quorum sensing, were identified. SAA and RH inhibit AI-2 synthesis through noncompetitive and competitive binding to S-ribosylhomocysteinase (LuxS). By inhibiting S. suis AI-2 quorum sensing, these compounds modulate the expression of adhesion genes and the synthesis of extracellular polysaccharides (EPS), reducing the adhesion ability of S. suis and ultimately inhibiting biofilm formation. Using LC‒MS/MS, we further analysed the impact of SAA and RH on the metabolic activity of S. suis, revealing the potential medicinal value of these compounds. Finally, the efficacy of SAA and RH against S. suis infection was validated in Galleria mellonella larvae, confirming their significant anti-infection effects.}, }
@article {pmid39905514, year = {2025}, author = {Park, H and Patil, TV and Lee, J and Kim, H and Cho, SJ and Lim, KT}, title = {NIR-activated catechol-functionalized nanodiamond nanofibers for accelerating on-demand MRSA and E. coli biofilm eradication.}, journal = {Journal of biological engineering}, volume = {19}, number = {1}, pages = {2}, pmid = {39905514}, issn = {1754-1611}, support = {RE-2023-00245155//Ministry of Education, KR/ ; NRF-2018R1A16A1A03025582//Ministry of Education, KR/ ; IITP-2024-RS-2023-00260267//Institute of Information &amp; Communications Technology Planning &amp; Evaluation (IITP)/ ; }, abstract = {The rise of antibiotic resistance has made bacterial infections a persistent global health issue. In particular, extracellular polymeric substances (EPS) secreted by bacteria limit the effectiveness of conventional antibiotics, making biofilm removal challenging. To address this, we created ND@PDA nanoparticles by coating the surface of nanodiamonds (ND) with polydopamine (PDA). These nanoparticles were then integrated into polyvinyl alcohol to fabricate PVA/ND@PDA nanofiber scaffolds, resulting in an innovative platform with enhanced photothermal, antibacterial and antibiofilm properties. Upon exposure to near-infrared (NIR) light, the scaffolds exhibited a significant photothermal activity, oxidative stress and effectively damaging key bacterial components, such as biofilm, bacterial membranes, and proteins. Additionally, the catechol groups in PDA provided strong cell adhesion and high biocompatibility on the nanofiber surface. Our research proposes a platform that not only effectively addresses antibiotic-resistant infections but also contributes to advancements in wound healing therapies by enabling controlled antibacterial action with minimal toxicity.}, }
@article {pmid39905465, year = {2025}, author = {Alshaybawee, MR and Asgari, S and Ghadersoltani, P and Mehrabian, A and Saniee, P}, title = {Exploring the antibacterial and anti-biofilm activity of two Iranian medical-grade kinds of honey on multidrug-resistant Pseudomonas aeruginosa.}, journal = {BMC complementary medicine and therapies}, volume = {25}, number = {1}, pages = {39}, pmid = {39905465}, issn = {2662-7671}, mesh = {*Honey ; *Pseudomonas aeruginosa/drug effects ; *Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology ; Iran ; *Microbial Sensitivity Tests ; *Drug Resistance, Multiple, Bacterial/drug effects ; Humans ; Thymus Plant/chemistry ; Citrus ; Pseudomonas Infections/drug therapy ; }, abstract = {INTRODUCTION: Pseudomonas aeruginosa is a prominent multidrug-resistant and biofilm-forming bacteria. Mono-floral honey, enriched with a variety of biological compounds, can be categorized as medical-grade honey due to its notable pharmacological benefits. In this study, two types of Iranian honey were thoroughly characterized, and the antimicrobial and anti-biofilm properties were examined against three clinical strains of multidrug-resistant P. aeruginosa.<br><br>METHODS: Citrus and Thyme honey from Alborz were selected based on physicochemical, phytochemical, and melissopalynological tests conducted from a medical perspective. The antibacterial activity of the honey samples against three clinical strains of multidrug-resistant P. aeruginosa isolated from wound infections was evaluated using both the well-diffusion and broth microdilution methods. Additionally, an antibiofilm assay was performed using the crystal violet method in microplates.<br><br>RESULTS: Both medical grade honey samples exhibited considerable antibacterial activity against the three P. aeruginosa isolates at 75-100% v/v concentrations with inhibition zones measuring between 15 and 30 mm. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) values for both types of honey were 6.25% v/v (final concentration). The antibiofilm assay indicated that both types of honey demonstrated varying levels of antibiofilm activity. Citrus honey at 9% concentration was the most effective, showing an average inhibition rate of 59%, while Citrus honey at 2.3% final concentration exhibited the least effectiveness with an average inhibition rate of 23%.<br><br>DISCUSSION: A thorough analysis of the honeys studied confirmed their authenticity and the presence of medicinal compounds. The results of honey tests correspond to the normal range (natural Honey) in the Council of the European Union. Based on the evaluation and compliance with the medical grade criteria including authenticity, health, qualities well botanical origin mentioned honey is classified in medical grade. The antibacterial results indicated that both Thyme and Citrus honeys effectively inhibit the growth and biofilm formation of P. aeruginosa. Therefore, these honeys may serve as natural and safe alternatives or adjuncts to conventional antibiotic therapy for wound healing and infection management.}, }
@article {pmid39904686, year = {2025}, author = {Yu, Y and Zhao, Y and He, Y and Pang, J and Yang, Z and Zheng, M and Yin, R}, title = {Corrigendum to "Inhibition of efflux pump encoding genes and biofilm formation by sub-lethal photodynamic therapy in methicillin susceptible and resistant Staphylococcus aureus" [Photodiagnosis and Photodynamic Therapy 102900 (2022) 102900].}, journal = {Photodiagnosis and photodynamic therapy}, volume = {}, number = {}, pages = {104492}, doi = {10.1016/j.pdpdt.2025.104492}, pmid = {39904686}, issn = {1873-1597}, }
@article {pmid39904546, year = {2025}, author = {Leong, PY and Tan, WQ and Choo, WS}, title = {Biofilm destruction activity of α-tocopherol against Staphylococcus aureus, Proteus mirabilis and Pseudomonas aeruginosa.}, journal = {FEMS microbiology letters}, volume = {}, number = {}, pages = {}, doi = {10.1093/femsle/fnaf020}, pmid = {39904546}, issn = {1574-6968}, abstract = {Antibiotic resistance and the persistence of sessile cells within biofilms complicate the eradication of biofilm-related infections using conventional antibiotics. This highlights the necessity for alternate therapy methods. The objective of this study was to investigate the biofilm destruction activity of α-tocopherol against Staphylococcus aureus, Proteus mirabilis and Pseudomonas aeruginosa on polystyrene. α-Tocopherol showed significant biofilm destruction activity on the pre-formed biofilms of S. aureus (45-46%), Pr. mirabilis (42-54%) and Ps. aeruginosa (28%). Resazurin assay showed that α-tocopherol disrupted all bacteria biofilms without interfering with their cell viability. Scanning electron microscope images showed lower bacterial cell count and less compacted cell aggregates on polystyrene surfaces after treatment with alpha-tocopherol. This study demonstrated the biofilm destruction activity of alpha-tocopherol against S. aureus, Pr. mirabilis and Ps. aeruginosa. α-Tocopherol could potentially be used to decrease biofilm-associated infections of these bacteria.}, }
@article {pmid39901410, year = {2025}, author = {}, title = {Expression of Concern: "In vitro biofilm inhibition efficacy of Aerva lanata flower extract against Gram negative and Gram-positive biofilm forming bacteria and toxicity analysis using Artemia salina" [Environ. Res., 238 (2023) 117118].}, journal = {Environmental research}, volume = {267}, number = {}, pages = {120625}, doi = {10.1016/j.envres.2024.120625}, pmid = {39901410}, issn = {1096-0953}, }
@article {pmid39901249, year = {2025}, author = {Lin, S and Li, X and Zhang, W and Shu, G and Tolker-Nielsen, T and Li, H and Xu, F and Lin, J and Peng, G and Zhang, L and Fu, H}, title = {Enhanced penetration and biofilm eradication by sophorolipid micelles encapsulating Honokiol: a comprehensive solution for biofilm-associated lung infections.}, journal = {Journal of nanobiotechnology}, volume = {23}, number = {1}, pages = {76}, pmid = {39901249}, issn = {1477-3155}, mesh = {*Biofilms/drug effects ; *Lignans/pharmacology/chemistry ; *Staphylococcus aureus/drug effects ; Animals ; *Biphenyl Compounds/pharmacology ; Mice ; *Micelles ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Staphylococcal Infections/drug therapy ; Bacterial Adhesion/drug effects ; Female ; Lung/microbiology ; Microbial Sensitivity Tests ; Mice, Inbred BALB C ; Humans ; Allyl Compounds ; Phenols ; }, abstract = {BACKGROUND: Biofilm-associated lung infections, particularly those caused by Staphylococcus aureus (S. aureus), pose significant clinical challenges to conventional therapies. S. aureus Biofilm infections are refractory to treatment due to the presence of persister bacterial cells and the barrier effect of unique extracellular polymeric substances (EPS).<br><br>RESULTS: This study describes the development of multifunctional micelles, HK-SL Ms, utilizing sophorolipid (SL) to encapsulate Honokiol (HK). HK-SL Ms potently disrupted the EPS barrier, killed some internal colonizing bacteria, and inhibited further bacterial adhesion. Consequently, the dynamic cycling of biofilms was hindered, achieving a promising removal of S. aureus biofilms. In vitro studies demonstrated that HK-SL Ms exhibited significant antimicrobial reduction of a 6.42 log10CFU/mL. HK-SL Ms eradicated 71.73% of biofilms by targeting extracellular polysaccharides, extracellular proteins, and viable cells within the biofilm. Additionally, 1.66 log10CFU/mL units of S. aureus within biofilms were killed. Moreover, HK-SL Ms inhibited 91.10% of early S. aureus biofilm formation by obstructing initial bacterial adhesion and the formation of extracellular polysaccharides and polysaccharide intercellular adhesins (PIA). Thus, the reestablishment and reinfection of S. aureus biofilms could be resolved promisingly. Biofilm infections are as predominant in acute pneumonia as in chronic cases, inducing similar lung inflammation. In a murine model of pneumonia infected by S. aureus, HK-SL Ms significantly reduced the bacterial load in the lungs, decreased inflammatory factor levels, and repaired lung tissue damage.<br><br>CONCLUSIONS: HK-SL Ms offers a novel strategy for the clinical treatment of biofilm-associated infections by dispersing and removing S. aureus biofilms and preventing new infections.}, }
@article {pmid39898557, year = {2025}, author = {Valle, J}, title = {Biofilm-associated proteins: from the gut biofilms to neurodegeneration.}, journal = {Gut microbes}, volume = {17}, number = {1}, pages = {2461721}, pmid = {39898557}, issn = {1949-0984}, mesh = {Humans ; *Biofilms/growth &amp; development ; *Gastrointestinal Microbiome ; *Neurodegenerative Diseases/microbiology/metabolism ; *Amyloid/metabolism ; *Bacterial Proteins/metabolism/genetics ; Animals ; Bacteria/metabolism/genetics ; alpha-Synuclein/metabolism/genetics ; }, abstract = {Human microbiota form a biofilm with substantial consequences for health and disease. Numerous studies have indicated that microbial communities produce functional amyloids as part of their biofilm extracellular scaffolds. The overlooked interplay between bacterial amyloids and the host may have detrimental consequences for the host, including neurodegeneration. This work gives an overview of the biofilm-associated amyloids expressed by the gut microbiota and their potential role in neurodegeneration. It discusses the biofilm-associated proteins (BAPs) of the gut microbiota, maps the amyloidogenic domains of these proteins, and analyzes the presence of bap genes within accessory genomes linked with transposable elements. Furthermore, the evidence supporting the existence of amyloids in the gut are presented. Finally, it explores the potential interactions between BAPs and α-synuclein, extending the literature on amyloid cross-kingdom interactions. Based on these findings, this study propose that BAP amyloids act as transmissible catalysts, facilitating the misfolding, accumulation, and spread of α-synuclein aggregates. This review contributes to the understanding of complex interactions among the microbiota, transmissible elements, and host, which is crucial for developing novel therapeutic approaches to combat microbiota-related diseases and improve overall health outcomes.}, }
@article {pmid39897976, year = {2025}, author = {Wandee, R and Sutthanut, K and Songsri, J and Weerapreeyakul, N and Rittirod, T and Tippayawat, P and Yangkruea, O and Jakcharoenpornchai, S}, title = {Prebiotic property of tamarind seed kernel on Bifidobacterium animalis growth and biofilm formation.}, journal = {Food chemistry: X}, volume = {25}, number = {}, pages = {102180}, pmid = {39897976}, issn = {2590-1575}, abstract = {This research explored the prebiotic potential of tamarind seed kernel powder (RTS), focusing on yield, nutritional composition, physicochemical properties using ATR-FTIR spectroscopy and colorimetric methods, effects on Bifidobacterium animalis in promoting the growth and biofilm formation compared to inulin using bacterial enumeration and crystal violet staining techniques, and the biofilm biomolecular composition characterization. The multi-nutrient composition RTS yielded 65.65 % (w/w), which significantly exhibited prebiotic activity in a dose-dependent manner with effective concentrations at 2.5 and 5 % RTS, stimulated B. animalis growth (rate 22 % • h[-1]) and enhanced biofilm formation (BFI = 256.71) exceeding the inulin. Moreover, ATR-FTIR spectroscopy and PCA analysis revealed the RTS-induced alteration of the biofilm's biomolecular composition, with a notable increase in amide A and a decrease in carboxylic hydroxyl groups. The study highlights RTS as a promising prebiotic agent with the potential for improving gut health, with further validation in the in vivo models being advisable.}, }
@article {pmid39897480, year = {2024}, author = {Panda, SK and Reynders, M and Kipanga, PN and Luyten, W}, title = {The anti-staphylococcal activity (planktonic and biofilm) of Cnestis ferruginea is due to benzoquinone, the oxidation product of hydroquinone.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1494589}, pmid = {39897480}, issn = {2235-2988}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Benzoquinones/pharmacology/chemistry ; *Staphylococcus aureus/drug effects ; *Hydroquinones/pharmacology/chemistry ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; *Oxidation-Reduction ; Plant Extracts/pharmacology/chemistry ; Inhibitory Concentration 50 ; }, abstract = {INTRODUCTION: Cnestis ferruginea is used frequently in African traditional medicine for treating infectious diseases. Previous bioassay-guided purification has identified hydroquinone as the major bio-active compound in the aforementioned plant, responsible for its antibacterial activity against Staphylococcus aureus. While the phenol hydroquinone can be directly extracted from the plant, it may undergo (reversible) oxidation under mild conditions to yield benzoquinone, a compound with known antimicrobial activity against i.a. S. aureus.<br><br>METHODS: We, examined whether hydroquinone or its oxidation product, benzoquinone, is the active compound against bacteria such as S. aureus. To achieve this we performed broth microdilution (planktonic) and biofilm activity tests against two different strains of S. aureus. The inhibitory concentrations (IC50) of benzoquinone and hydroquinone under various circumstances were compared, assessing their stability, and examining their effectiveness against two strains of S. aureus (Rosenbach and USA 300) in both planktonic and biofilm environments.<br><br>RESULTS: Benzoquinone demonstrated antibacterial activity against S. aureus Rosenbach and USA 300 with IC50 of 6.90 &#xb1; 2.30 mM and 7.72 &#xb1; 2.73 mM, respectively, while the corresponding values for hydroquinone were 15.63 &#xb1; 2.62 mM and 19.21 &#xb1; 4.84 mM, respectively. However, when oxidation was prevented by the addition of antioxidants such as ascorbic acid or glutathione, hydroquinone lost its antibacterial property, while benzoquinone retained activity. Comparing conditions in which hydroquinone could convert into benzoquinone against conditions in which this conversion was inhibited, showed that hydroquinone alone did not inhibit bacterial growth of S. aureus, while benzoquinone alone did.<br><br>DISCUSSION: These results prove that the oxidation product benzoquinone is responsible for the antimicrobial activity previously ascribed to hydroquinone.}, }
@article {pmid39896144, year = {2025}, author = {Afzal, M and Carda-Diéguez, M and Bloch, S and Thies, LGS and Mira, A and Schäffer, C}, title = {Decoding gene expression dynamics in planktonic and biofilm cells of Streptococcus mutans: regulation and role of mutanofactin genes in biofilm formation.}, journal = {Frontiers in oral health}, volume = {6}, number = {}, pages = {1535034}, pmid = {39896144}, issn = {2673-4842}, abstract = {INTRODUCTION: Dental caries is the most prevalent chronic infectious disease globally, with Streptococcus mutans recognized as a primary causative agent due to its acidogenicity and robust biofilm-forming ability. In S. mutans biofilm formation, the role of autoinducers has been extensively studied, while the influence of other small molecules remains largely unexplored. Mutanofactins, a class of polyketide/non-ribosomal lipopeptide secondary metabolites, are emerging as potential modulators of S. mutans biofilm development.<br><br>METHODS: Transcriptomic analysis was conducted to examine gene expression patterns in S. mutans NMT4863 across distinct growth phases and lifestyles, aiming to identify metabolic factors influencing biofilm formation. Transcriptomic profiles were compared between cells in early-, mid-, and late-exponential-, and stationary phase, as well as between planktonic and biofilm cells. Differentially expressed genes were identified, and pathway analyses revealed significant alterations in key metabolic and regulatory pathways. Specifically, the biosynthetic mutanofactin gene cluster was analyzed via quantitative real-time polymerase chain reaction.<br><br>RESULTS: Several genes and operons were differentially expressed across the tested growth phases, with 1,095 genes showing differential expression between stationary-phase, planktonic and biofilm cells. Pathway analysis revealed significant changes in ascorbate metabolism, carbohydrate utilization and transport systems, lipoic acid metabolism, bacterial toxin pathways, two-component regulatory systems, and secondary metabolite biosynthesis. Notably, expression of the muf gene cluster, was elevated in early exponential-phase cells relative to stationary-phase cells. Additionally, the mufCDEFGHIJ genes were identified as components of a single transcriptional unit (muf operon). MufC, a transcriptional regulator of the TetR/AcrR-family, acts as a positive regulator of the muf operon in strain NMT4863. Bioinformatic analysis pinpointed a 20-bp regulatory sequence in the muf operon promoter region (5'-AAATGAGCTATAATTCATTT-3'). Interestingly, the muf operon was found to be significantly downregulated in biofilm cells.<br><br>CONCLUSION: This study provides key insights into gene expression dynamics that drive biofilm formation in S. mutans NMT4863, with a particular emphasis on the role of the muf operon. This operon is governed by the TetR/AcrR-family regulator MufC and plays a central role in biofilm development, offering a novel perspective on the molecular basis of S. mutans biofilm formation and resilience.}, }
@article {pmid39895941, year = {2024}, author = {Zhou, J and Ma, Q and Liang, J and Pan, Y and Chen, Y and Yu, S and Liu, Y and Zhang, Q and Li, Y and Zou, J}, title = {smu_1558c-mediated regulation of growth and biofilm formation in Streptococcus mutans.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1507928}, pmid = {39895941}, issn = {1664-302X}, abstract = {Streptococcus mutans is a key etiological agent in dental caries, owing to its strong ability to form biofilms through carbohydrate fermentation. Protein acetylation, facilitated by GNAT family acetyltransferases, plays a critical regulatory role in bacterial physiology, but its impact on S. mutans remains largely unexplored. In this study, we investigated the role of the GNAT family acetyltransferase encoded by smu_1558c in regulating the growth and biofilm formation of S. mutans. The deletion of smu_1558c resulted in impaired growth, reduced biofilm formation, and diminished synthesis of water-insoluble extracellular polysaccharides (EPS). Proteomic analysis revealed 166 differentially expressed proteins in the deletion mutant, with significant enrichment in pathways related to carbohydrate transport and metabolism, and translation. Notably, glucosyltransferases GtfB and GtfC, key enzymes in biofilm formation, were significantly downregulated in the deletion mutant, while ClpL, a Clp-like ATP-dependent protease involved in protein homeostasis under stress conditions, was highly upregulated. These findings highlight that acetyltransferase smu_1558c plays a crucial role in the growth, biofilm formation, and EPS synthesis of S. mutans through its regulation of carbohydrate transport and metabolism pathways, as well as stress response mechanisms. This study provides novel insights into the molecular mechanisms governing S. mutans pathogenicity and suggests potential therapeutic targets for caries prevention.}, }
@article {pmid39895061, year = {2025}, author = {Melissa, B and Elisa, B and Gabriella, C and Maurizio, A and Ombretta, DA and Andrea, DC and Eckert, EM and Flavia, M}, title = {Bacterial Diversity of Marine Biofilm Communities in Terra Nova Bay (Antarctica) by Culture-Dependent and -Independent Approaches.}, journal = {Environmental microbiology}, volume = {27}, number = {2}, pages = {e70045}, pmid = {39895061}, issn = {1462-2920}, support = {//Consorzio Interuniversitario Biotecnologie/ ; PNRA 16_00105//Italian Ministry of University and Research (MIUR)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Bacteria/classification/genetics/isolation &amp; purification ; *Bays/microbiology ; *RNA, Ribosomal, 16S/genetics ; *Biodiversity ; Antarctic Regions ; Seawater/microbiology ; Phylogeny ; DNA, Bacterial/genetics ; Microbiota ; Sequence Analysis, DNA ; }, abstract = {Applying both culture-independent and -dependent approaches, bacterial diversity of marine biofilm communities colonising polyvinyl chloride panels submerged in Terra Nova Bay (Ross Sea, Antarctica) was investigated. Panels were deployed in two sites subjected to a different degree of anthropogenic impact (Road Bay [RB] impacted site and Punta Stocchino [PTS] control site). Biofilm samples were collected after 3 or 12 months to evaluate both short- and long-term microbial colonisation. Taxonomic composition of the microbial community was studied by 16S rRNA gene amplicon sequencing. Proteobacteria was the predominant phylum, followed by Bacteroidetes, Actinobacteria, Verrucomicrobia and Firmicutes. Impacted RB biofilms were found to contain a relevant fraction of potentially pathogenic bacterial genera, accounting for 27.49% of the whole community. A total of 86 psychrotolerant bacterial strains were isolated from the biofilm samples using culture-dependent techniques designed to enrich in Actinobacteria. These strains were assigned to three different phyla: Actinobacteria (54.65%), Firmicutes (32.56%) and Proteobacteria (12.79%). 2.73% of genera identified by metabarcoding were recovered also through cultivation, while 11 additional genera were uniquely yielded by cultivation. Functional screening of the isolates revealed their hydrolytic and oxidative enzyme activity patterns, giving new insights into the metabolic and biotechnological potential of microbial biofilm communities in Terra Nova Bay seawater.}, }
@article {pmid39894846, year = {2025}, author = {Chatzimpinou, A and Diehl, A and Harhoff, AT and Driller, K and Vanslembrouck, B and Chen, JH and Kairišs, K and Loconte, V and Le Gros, MA and Larabell, C and Turgay, K and Oschkinat, H and Weinhardt, V}, title = {Soft X-ray tomography reveals variations in B. subtilis biofilm structure upon tasA deletion.}, journal = {NPJ biofilms and microbiomes}, volume = {11}, number = {1}, pages = {23}, pmid = {39894846}, issn = {2055-5008}, support = {P30 GM138441/GM/NIGMS NIH HHS/United States ; DE-AC02-05CH11231//DOE Biological and Environmental Research Project/ ; 101017116//H2020 European Research Council/ ; SPP1879//Deutsche Forschungsgemeinschaft/ ; 101120151//HORIZON EUROPE Marie Sklodowska-Curie Actions/ ; 3D Matter Made to Order//Excellence Strategy of the Federal and State Governments of Germany/ ; P30GM138441//NIH NIGMS/ ; cohort 2022//Joachim Herz Stiftung/ ; }, mesh = {*Biofilms/growth &amp; development ; *Bacillus subtilis/genetics/physiology ; *Bacterial Proteins/genetics/metabolism ; Tomography, X-Ray ; Gene Deletion ; Imaging, Three-Dimensional ; Extracellular Matrix ; }, abstract = {Bacterial biofilms are complex cell communities within a self-produced extracellular matrix, crucial in various fields but challenging to analyze in 3D. We developed a "biofilm-in-capillary" growth method compatible with full-rotation soft X-ray tomography, enabling high-resolution 3D imaging of bacterial cells and their matrix during biofilm formation. This approach offers 50 nm isotropic spatial resolution, rapid imaging, and quantitative native analysis of biofilm structure. Using Bacillus subtilis biofilms, we detected coherent alignment and chaining of wild-type cells towards the oxygen-rich capillary tip. In contrast, the ΔtasA genetic knock-out showed a loss of cellular orientation and changes in the extracellular matrix. Adding TasA protein to the ΔtasA strain restored matrix density and led to cell assembly compaction, but without the chaining observed in wild-type biofilms. This scalable and transferable approach opens new avenues for examining biofilm structure and function across various species, including mixed biofilms, and response to genetic and environmental factors.}, }
@article {pmid39894266, year = {2025}, author = {Tang, Y and Chen, Y and Qi, YD and Yan, HY and Peng, WA and Wang, YQ and Huang, QX and Liu, XH and Ye, JJ and Yu, Y and Zhang, XZ and Huang, C}, title = {Engineered Bdellovibrio bacteriovorus enhances antibiotic penetration and biofilm eradication.}, journal = {Journal of controlled release : official journal of the Controlled Release Society}, volume = {380}, number = {}, pages = {283-296}, doi = {10.1016/j.jconrel.2025.01.075}, pmid = {39894266}, issn = {1873-4995}, abstract = {Biofilms increase bacterial resistance to antibiotics, as conventional antibiotic doses are often ineffective at penetrating the biofilm matrix to eliminate bacteria. Recent research has shown that the Gram-negative predator bacterium Bdellovibrio bacteriovorus can penetrate Gram-positive bacterial biofilms during its predation phase and benefit from them without direct predation. Here, based on the penetration ability of B. bacteriovorus, we constructed antibiotic-loaded liposome-engineered B. bacteriovorus as a drug delivery strategy for biofilm-related diseases. As a "living antibiotic," B. bacteriovorus can prey on Gram-negative bacteria, penetrate biofilms, and disrupt their dense structure. During this process, the rapid movement of B. bacteriovorus enhances the delivery of antibiotic-loaded liposomes into the biofilm, promoting efficient antibiotic release and improving biofilm eradication. Our findings demonstrate that this engineered living antibiotic strategy significantly improves the control and removal of bacterial biofilms, accelerates the elimination of dental plaque, promotes wound healing, and holds promise as a novel platform for treating biofilm-related infections.}, }
@article {pmid39893937, year = {2025}, author = {Ma, Z and Ma, J and Li, J and Wang, Z and Wei, L and Ali, A and Zuo, Y and Cai, X and Meng, Q and Qiao, J}, title = {Regulatory roles of the AraC family transcription factor yeaM in the virulence and biofilm formation of Salmonella Typhimurium.}, journal = {International journal of food microbiology}, volume = {431}, number = {}, pages = {111088}, doi = {10.1016/j.ijfoodmicro.2025.111088}, pmid = {39893937}, issn = {1879-3460}, abstract = {Salmonella Typhimurium (S. typhimurium) is a significant zoonotic pathogen responsible for gastroenteritis and severe systemic infections in various hosts. The AraC family transcription factors are key gene expression regulators in prokaryotes, essential for bacterial adaptation to the environment and virulence. Despite their importance, the role of yeaM, a member of this family in S. typhimurium, remains unexplored. To elucidate yeaM regulatory function in virulence and biofilm formation, we engineered mutant and complementary strains of the yeaM gene using homologous recombination. We assessed their capabilities in biofilm formation under different conditions, macrophage adherence and invasion, and virulence in mice. Additionally, we identified potential target genes regulated by yeaM through transcriptome sequencing and confirmed these findings using an electrophoretic mobility shift assay (EMSA) and a dual-luciferase reporter assay. Our results demonstrate that, compared to the parental strain SL1344 and the complemented strain CΔyeaM, the ΔyeaM strain exhibited significantly enhanced biofilm formation, increased invasion of mouse intestinal epithelial cells, enhanced intracellular proliferation within macrophages, and elevated induction of macrophage apoptosis. Furthermore, the ΔyeaM deletion strain displayed significantly increased virulence in mice and enhanced proliferation in milk. Transcriptome analysis revealed that S. typhimurium pathogenicity island 4 (SPI4) genes (siiA, siiB, siiC, siiD, siiF, and siiE) were significantly upregulated following the deletion of the yeaM gene. EMSA and dual-luciferase reporter assays further showed that the yeaM protein can bind to the promoter of the siiA gene and suppress its expression, thereby modulating the biofilm formation and virulence of S. typhimurium.}, }
@article {pmid39893414, year = {2025}, author = {Zhang, K and Huang, Y and Jiang, Y and Liu, T and Kong, J and Cai, S and Wen, Z and Chen, Y}, title = {Effect of Candida albicans' supernatant on biofilm formation and virulence factors of Pseudomonas aeruginosa through las/rhl System.}, journal = {BMC microbiology}, volume = {25}, number = {1}, pages = {60}, pmid = {39893414}, issn = {1471-2180}, support = {Z20190940//Guangxi Zhuang Autonomous Region Health Commission self funded research project/ ; 81760743//National Natural Science Foundation of China/ ; KLLAD202204//Open Project of Key Laboratory of Longevity and Aging-related Diseases (Guangxi Medical University), Ministry of Education/ ; GUIZAICHONGKAI 202206//Open Project of Guangxi Key Laboratory of Regenerative Medicine/ ; }, mesh = {*Biofilms/growth &amp; development ; *Pseudomonas aeruginosa/genetics/pathogenicity/physiology ; *Candida albicans/pathogenicity/genetics/physiology/drug effects ; *Virulence Factors/genetics/metabolism ; *Quorum Sensing ; *Bacterial Proteins/genetics/metabolism ; Virulence ; Animals ; Trans-Activators/genetics/metabolism ; Mice ; Pseudomonas Infections/microbiology ; }, abstract = {Pseudomonas aeruginosa (P. aeruginosa) and Candida albicans (C. albicans) are opportunistic pathogens whose mixed infections can exacerbate microbial dissemination and drug resistance, contributing to high mortality and morbidity rates among infected individuals. Few studies have explored the impact of C. albicans supernatant on P. aeruginosa, and the underlying mechanisms of such mixed infections remain unclear. In this study, we investigated the effects of C. albicans supernatant on biofilm formation and virulence factor activity in wild-type P. aeruginosa PAO1 and its quorum sensing-deficient mutants, ΔlasIrhlI and ΔlasRrhlR. Our results demonstrated that the biofilm formation capability and virulence were significantly higher in the PAO1 group compared to the ΔlasIrhlI and ΔlasRrhlR groups. Furthermore, exposure to C. albicans supernatant significantly enhanced both the biofilm formation and virulence of PAO1, whereas no significant changes were observed in the ΔlasIrhlI and ΔlasRrhlR mutants relative to their respective controls. These findings suggest that C. albicans supernatant may modulate P. aeruginosa biofilm formation and virulence via the las/rhl quorum sensing system.}, }
@article {pmid39892261, year = {2025}, author = {Yang, Z and Lin, S and Wang, H and Zhou, J and Lin, H and Zhou, J}, title = {Simultaneous partial nitrification, endogenous and autotrophic denitrification in a single-stage electrolysis-integrated sequencing batch biofilm reactor (E-SBBR) for stable and enhanced kitchen digested wastewater treatment.}, journal = {Journal of environmental management}, volume = {375}, number = {}, pages = {124200}, doi = {10.1016/j.jenvman.2025.124200}, pmid = {39892261}, issn = {1095-8630}, mesh = {*Nitrification ; *Biofilms ; *Wastewater ; *Bioreactors ; *Denitrification ; *Waste Disposal, Fluid/methods ; Electrolysis ; Nitrogen/metabolism ; Autotrophic Processes ; Ammonia/metabolism ; }, abstract = {Simultaneous partial nitrification-denitrification (SPND) is a promising process for nitrogen (N) removal from kitchen digested wastewater characterized by a low C/N ratio. However, its widespread application is often restricted due to the unstable partial nitrification and unsatisfactory denitrification performance. This work developed a novel simultaneous partial nitrification, endogenous and autotrophic denitrification process using a single-stage electrolysis-integrated sequencing batch biofilm reactor (E-SBBR) with anoxic/electro-anaerobic/aerobic operating strategy. The novel process considerably enhanced the stability and N removal efficiency (NH4[+]-N>94.5% and TN>90.8%) of the SPND process. The pre-electro-anaerobic phase achieved alkalinity and H2 generation, and intracellular carbon storage. The increased alkalinity resulted in increased free ammonia (FA) which secured complete suppression of nitrite-oxidizing bacteria (NOB). SPND efficiency in the aerobic phase was dramatically improved using polyhydroxyalkanoates (PHAs) and H2 as electron donors for endogenous and autotrophic denitrification. Microbial community analysis indicated the successful washout of NOB and the enrichment of ammonia-oxidizing bacteria (AOB), denitrifying glycogen accumulating organisms (DGAOs), autotrophic and heterotrophic denitrifiers in the system. This research presents a distinctive SPND process for intensified kitchen digested wastewater treatment and gives insights into the underlying mechanism.}, }
@article {pmid39892235, year = {2025}, author = {Pan, T and Guo, Z and Hu, S and Dong, D and Li, J and Yang, X and Dai, Y and Li, L and Wu, F and Wu, Z and Xi, S}, title = {Additive release and prediction of biofilm-colonized microplastics in three typical freshwater ecosystems.}, journal = {The Science of the total environment}, volume = {965}, number = {}, pages = {178671}, doi = {10.1016/j.scitotenv.2025.178671}, pmid = {39892235}, issn = {1879-1026}, mesh = {*Microplastics/analysis ; *Water Pollutants, Chemical/analysis ; China ; *Biofilms ; *Fresh Water ; *Environmental Monitoring ; *Ecosystem ; Plastics/analysis ; }, abstract = {Widely used plastics are discarded and broken into microplastics (MPs), threatening the health of plants and animals, and affecting the natural world. The global spread of plastic additives, as unavoidable components in plastic preparation, raises concerns about their leaching in different environments. This paper aims to infer the leaching of hazardous plastic additives (e.g.FP-127 fluorescent additives) by investigating the effect of biofilm communities on the release of additives from plastics after 35 days of incubation in three typical freshwater ecosystems (Hubing Pool, Baogong Park, and Feihe River) in Hefei, China. In this research, we prepared different plastics, crushed them and then put them into natural freshwater we sampled in the laboratory. The results showed that the biofilms attached to the various MPs contained different biomass that were related to water environmental conditions and the properties of MPs. Compared to the natural release in deionized water, the concentration of leaching MPs additives can be 5, 10, and 20 times higher in Hubing Pool, Baogong Park, and Feihe River, respectively. The analysis results also clearly showed that the relative abundance of core communities was proportional to FP-127 additive leaching from the MPs into the surrounding environment. Moreover, we also modeled two equations to predict the release of additives. These findings would be valuable for predicting the potential of MPs to release toxic additives under different freshwater ecosystems.}, }
@article {pmid39892023, year = {2025}, author = {Guo, M and Wang, H and Zhang, H and Bo, Z and Zhang, C and Zhang, X and Wu, Y}, title = {Identifcation of the genes involved in biofilm formation of Avibacterium paragallinarum using random transposon mutagenesis.}, journal = {Veterinary microbiology}, volume = {302}, number = {}, pages = {110410}, doi = {10.1016/j.vetmic.2025.110410}, pmid = {39892023}, issn = {1873-2542}, abstract = {Infectious coryza (IC) is a respiratory disease in poultry caused by Avibacterium paragallinarum (Av. paragallinarum). The disease caused growth retardation in broilers and reduced egg production in laying hens, resulting in significant economic losses to the global chicken industry. The biofilm is an important virulence factor for many bacterial pathogens, yet there is a paucity of research on the biofilm of Av. paragallinarum. This study aimed to construct a random mutant library of Av. paragallinarum using the Tn5-Kan transposon to identify genes involved in biofilm formation. A total of approximately 3000 mutants were obtained, and 38 of them demonstrated a reduction in biofilm formation of 70-90 % by crystal violet staining. The transposon insertion sites were further determined by chromosome walking, and 17 functional genes related to biofilm formation were identified. According to the functional analysis of the mutated genes, 14 mutants with mutated genes associated with energy metabolism, cell membrane formation, gene transcription and translation, and material transmembrane transport were screened to further explore their biological characteristics and pathogenicity in vivo and in vitro. The results indicated that the growth performance, resistance to disinfectants, adhesion and invasion ability to DF-1 cells and pathogenicity of the 14 mutants were reduced. The 14 mutants displayed increased sensitivity to antibiotics but did not show significant changes in hemagglutination titer or antiserum bactericidal ability. It is noteworthy that the M-76 mutant exhibited a marked reduction in pathogenicity. Following challenge, the experimental chickens did not present any clinical symptoms or pathological changes for a period of seven days, and the respiratory tract bacterial shedding was also the lowest. This indicates that a deficiency in biofilm formation reduces the pathogenicity of Av. paragallinarum. This study will contribute to our understanding of the molecular mechanism of biofilm formation of Av. paragallinarum and further study the pathogenesis of Av. paragallinarum.}, }
@article {pmid39890071, year = {2025}, author = {Medina, C and Manriquez, D and Gonzalez-Córdova, BA and Pacha, PA and Vidal, JM and Oliva, R and Latorre, AA}, title = {Biofilm Forming Ability of Staphylococcus aureus on Materials Commonly Found in Milking Equipment Surfaces.}, journal = {Journal of dairy science}, volume = {}, number = {}, pages = {}, doi = {10.3168/jds.2024-25416}, pmid = {39890071}, issn = {1525-3198}, abstract = {The presence of biofilms on milking equipment on dairy farms can be a source of bulk tank milk contamination, as well as a potential source of intramammary infections for cows. The biofilm forming ability of bacteria, including Staphylococcus aureus, may differ depending on factors such as the intrinsic ability of bacteria to form biofilms, as well as the roughness and type of material of the surfaces. We investigated the ability of S. aureus to form biofilms on coupons made of Stainless Steel, Nitrile (Buna-N) Rubber, Ethylene Propylene Diene Monomer (EPDM) Rubber, Silicone Rubber, Borosilicate Glass, Polycarbonate and Polyvinyl Chloride, which are materials commonly used to manufacture pieces of milking equipment. Three S. aureus strains isolated from biofilms naturally formed in milking equipment on dairy farms, and previously characterized as "high," "medium," or "low" adherence ability by microtiter plate assay, were analyzed to assess their ability to form in vitro biofilms using a CDC Biofilm Reactor. Bacterial counts of suspended biofilms and Scanning Electron Microscopy were performed on coupons of each material. The highest bacterial counts were observed in Buna-N surfaces for high adherence (L1-1171, mean = 4.54 Log10 cfu/mL), medium adherence (L1-030, mean = 4.18 Log10 cfu/mL), and low adherence (L1-256, mean = 3.71 Log10 cfu/mL) S. aureus. The biofilm forming ability for a same S. aureus strain, regardless their adherence abilities, was not significantly different among all tested surface materials, except of Buna-N Rubber, for which all 3 strains had an increased ability to form biofilms. In a same material, no statistically significant differences were observed among strains, except for Buna-N and EPDM Rubber in which the highly adherent S. aureus strain (L1-1171) had a greater biofilm formation as compared with other strains. Regular replacement of rubber parts of milking equipment is warranted to reduce the risk of biofilm formation.}, }
@article {pmid39887335, year = {2025}, author = {Cai, Y and Boltz, JP and Rittmann, BE}, title = {Modeling the Performance of an Anaerobic Moving Bed Biofilm Reactor.}, journal = {Biotechnology and bioengineering}, volume = {}, number = {}, pages = {}, doi = {10.1002/bit.28938}, pmid = {39887335}, issn = {1097-0290}, support = {//This work was supported by funding from PepsiCo and generous donations from the Swette Family Endowment, Woodard &amp; Curran Inc., the Natural Science Foundation of China (Grant No. 52200087), the China Postdoctoral Science Foundation funded project (2022M710654), the Fundamental Research Funds for the Central Universities (2412022QD019). Yuhang Cai also gratefully acknowledges the financial support from China Scholarship Council./ ; }, abstract = {Sub-models representing transformation processes by microorganisms and hydrolases, a one-dimensional (1-D) biofilm, and a bioreactor were integrated to simulate organic-matter fermentation and methane (CH4) production in an anaerobic moving bed biofilm reactor (AnMBBR). The integrated models correctly represented all experimental observations and identified mechanisms underlying how and why AnMBBR performance changed when the volumetric loading rate (VLR) of total chemical oxygen demand (TCOD) increased from 3.9 to 19.5 kg CODT/m[3]-d. The fractional removal of TCOD and CH4 production decreased as the VLR of TCOD increased, in part, due to an increasing biofilm thickness that filled the protected channels in the interior of the plastic carriers and led to a decrease in biofilm surface area and an increase in the mass-transfer boundary layer. Also, the ~25-day duration for each VLR of TCOD was too brief to allow the biofilm to establish a new quasi-steady state with respect to biofilm thickness. The mechanistic understanding of how biofilm characteristics and process performance respond to increased VLR of TCOD can be applied in engineering practice to improve AnMBBR process design and operation.}, }
@article {pmid39887017, year = {2025}, author = {Wang, C and Shahriar, SMS and Su, Y and Xie, J}, title = {Versatile nanomaterials used in combatting biofilm infections.}, journal = {Nanomedicine (London, England)}, volume = {}, number = {}, pages = {1-18}, doi = {10.1080/17435889.2025.2459049}, pmid = {39887017}, issn = {1748-6963}, abstract = {Microbial infections are a pressing global health issue, exacerbated by the rise of antibiotic-resistant bacteria due to widespread antibiotic overuse. This resistance diminishes the effectiveness of current treatments, intensifying the need for new antimicrobial agents and innovative drug delivery strategies. Nanotechnology presents promising solutions, leveraging the unique properties of nanomaterials such as tunable optical and electronic characteristics, nanoscale size, and high surface-to-volume ratios. These features enhance their effectiveness as innovative antimicrobial agents and versatile drug delivery systems. This minireview classifies antimicrobial nanomaterials into four categories based on their mechanisms of action: thermal generation, reactive oxygen species generation, gas generation, and nanocarrier systems such as liposomes, polymersomes, and metal-organic frameworks. Uniquely, this review integrates a comparative analysis of these mechanisms, highlighting their relative advantages, limitations, and applications across diverse microbial targets. Additionally, it identifies emerging trends in the field, providing a forward-looking perspective on how recent advancements in nanotechnology can be leveraged to address unmet clinical needs. Finally, this article discusses future directions and emerging opportunities in antimicrobial nanotechnology.}, }
@article {pmid39885598, year = {2025}, author = {Nishi, K and Gondaira, S and Hirano, Y and Ohashi, M and Sato, A and Matsuda, K and Iwasaki, T and Kanda, T and Uemura, R and Higuchi, H}, title = {Biofilm characterisation of Mycoplasma bovis co-cultured with Trueperella pyogenes.}, journal = {Veterinary research}, volume = {56}, number = {1}, pages = {22}, pmid = {39885598}, issn = {1297-9716}, support = {23K05574//Japan Society for the Promotion of Science London/ ; }, mesh = {*Biofilms/growth &amp; development ; Animals ; *Mycoplasma bovis/physiology ; *Actinomycetaceae/physiology ; Cattle ; *Cattle Diseases/microbiology/physiopathology ; *Actinomycetales Infections/veterinary/microbiology ; Coinfection/veterinary/microbiology ; Coculture Techniques/veterinary ; Pneumonia, Mycoplasma/veterinary/microbiology ; }, abstract = {Mycoplasma pneumonia, caused by Mycoplasma bovis (Mycoplasmopsis bovis; M. bovis), is linked with severe inflammatory reactions in the lungs and can be challenging to treat with antibiotics. Biofilms play a significant role in bacterial persistence and contribute to the development of chronic lesions. A recent study has shown that polymicrobial interactions between species are an important factor in biofilm formation, yet the precise mechanism of biofilm formation in M. bovis remains unknown. By assuming multiple pathogen infections in the bovine respiratory disease complex (BRDC), this study examined the characterisation of the polymicrobial relationship between M. bovis and Trueperella pyogenes (T. pyogenes) during biofilm formation. Autopsies were performed on four Holstein calves (two chronic Mycoplasma pneumonia calves and two control calves). Bacterium-like aggregation structures (> 10 μm), which were assumed to be biofilms of M. bovis in vivo, were observed adhering to the cilia in calves with Mycoplasma pneumonia. M. bovis released an extracellular matrix to connect with neighbouring bacteria and form a mature biofilm on the plate. Biofilm formation in the co-culture of M. bovis and T. pyogenes (strain T1: 1 × 10[5] and 1 × 10[6] CFU/well) significantly increased (p < 0.05 and p < 0.01; 64.1% and 64.8% increase) compared to that in a single culture of these bacteria. Furthermore, some large aggregates (> 40 μm), composed of M. bovis and T. pyogenes, were observed. The morphological characteristics of this biofilm were similar to those observed in vivo compared to a single culture. In conclusion, the polymicrobial interaction between M. bovis and T. pyogenes induces biofilm formation, which is associated with increased resistance to antimicrobial agents, and this exacerbates the progression of chronic Mycoplasma pneumonia.}, }
@article {pmid39885460, year = {2025}, author = {Guo, T and Wang, D and Gao, SS}, title = {The antibiofilm effect and mechanism of silver nanowire-modified glass ionomer cement against multi-species oral biofilm.}, journal = {BMC oral health}, volume = {25}, number = {1}, pages = {160}, pmid = {39885460}, issn = {1472-6831}, support = {2023XAKJ0103067//Scientific Research Foundation of State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory/ ; 2023XAKJ0103067//Scientific Research Foundation of State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory/ ; 2023XAKJ0103067//Scientific Research Foundation of State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory/ ; }, mesh = {*Biofilms/drug effects ; *Glass Ionomer Cements/pharmacology/chemistry ; *Silver/chemistry/pharmacology ; *Streptococcus mutans/drug effects ; *Nanowires/chemistry ; Microscopy, Electron, Scanning ; Surface Properties ; Microscopy, Confocal ; Streptococcus sobrinus/drug effects ; Limosilactobacillus fermentum ; Lacticaseibacillus rhamnosus/drug effects ; Materials Testing ; Compressive Strength ; Microscopy, Atomic Force ; Metal Nanoparticles/chemistry ; Hardness ; Wettability ; Lactic Acid ; Humans ; }, abstract = {BACKGROUND: To investigate the antibiofilm effect and mechanism of the silver nanowire (AgNW)-modified glass ionomer cement (GIC) against multi-species oral biofilm, and to examine the mechanical and biochemical properties of this novel GIC material.<br><br>METHODS: Conventional GIC was incorporated with different concentrations of AgNW and silver nanoparticles (AgNP). Multi-species biofilms of Streptococcus mutans, Streptococcus sobrinus, Lactobacillus fermentum, and Lactobacillus rhamnosus were cultured for 72&#xa0;h on GIC specimens. Scanning electron microscopy (SEM) was adopted to examine the accumulation of biofilm on GIC surfaces. A live/dead assay was performed to assess the viability of bacteria. Extracellular polysaccharides (EPS) were labelled with Alexa Fluor 647-labelled dextran conjugate and then observed by a confocal laser scanning microscope (CLSM). The D/L-Lactic Acid Assay Kit was used to evaluate the lactic acid production of the multi-species biofilms. Compressive strength, surface roughness, hardness, and wettability were measured by a universal testing machine, an atomic force microscope (AFM), a Vickers microhardness tester, and a contact angle meter, respectively. Colour stability and fluoride release of GIC specimens were assessed by VITA Easyshade&#xae; V and ion chromatography. Cell counting kit-8 (CCK-8) was used to study cytotoxicity.<br><br>RESULTS: SEM images showed that fewer biofilms were accumulated on the AgNW-GIC surfaces. The live/dead assay showed that the ratio of live bacteria was significantly lower in AgNW-GIC groups than in conventional GIC (5.8% vs. 100%, p&#x2009;<&#x2009;0.0001). The EPS production was significantly less in AgNW-GIC groups compared to conventional GIC (p&#x2009;<&#x2009;0.0001). There is no difference between groups regarding lactic acid production and fluoride release. The mechanical strength including compressive strength, surface roughness, hardness, and wettability were comparable between groups. The colour change between AgNW-GIC and conventional GIC was much milder than that between AgNP-GIC and conventional GIC. The results of cytotoxicity showed no significant differences in cell viability between groups.<br><br>CONCLUSIONS: This study demonstrated that AgNW-GIC had an excellent antibiofilm effect against multi-species oral biofilm, comparable mechanical and biochemical properties, and did not significantly affect the colour stability of GIC. The antibiofilm mechanism of AgNW-GIC may be related to inhibiting the viability and EPS production of bacteria.}, }
@article {pmid39885187, year = {2025}, author = {Sung, K and Park, M and Kweon, O and Paredes, A and Savenka, A and Khan, SA}, title = {Proteomic insights into dual-species biofilm formation of E. coli and E. faecalis on urinary catheters.}, journal = {Scientific reports}, volume = {15}, number = {1}, pages = {3739}, pmid = {39885187}, issn = {2045-2322}, support = {E0770601//U.S. Food and Drug Administration/ ; }, mesh = {*Biofilms/growth &amp; development ; *Enterococcus faecalis/physiology/metabolism/growth &amp; development ; *Escherichia coli/physiology/metabolism ; *Urinary Catheters/microbiology ; *Proteomics/methods ; Humans ; Bacterial Proteins/metabolism/genetics ; Proteome/metabolism ; }, abstract = {Infections associated with urinary catheters are often caused by biofilms composed of various bacterial species that form on the catheters' surfaces. In this study, we investigated the intricate interplay between Escherichia coli and Enterococcus faecalis during biofilm formation on urinary catheter segments using a dual-species culture model. We analyzed biofilm formation and global proteomic profiles to understand how these bacteria interact and adapt within a shared environment. Our findings demonstrated dynamic population shifts within the biofilms, with E. coli initially thriving in the presence of E. faecalis, then declining during biofilm development. E. faecalis exhibited a rapid decrease in cell numbers after 48 h in both single- and dual-species biofilms. Interestingly, the composition of the dual-species biofilms was remarkably diverse, with some predominantly composed of E. coli or of E. faecalis; others showed a balanced ratio of both species. Notably, elongated E. faecalis cells were observed in dual-species biofilms, a novel finding in mixed-species biofilm cultures. Proteomic analysis revealed distinct adaptive strategies E. coli and E. faecalis employed within biofilms. E. coli exhibited a more proactive response, emphasizing motility, transcription, and protein synthesis for biofilm establishment; whereas E. faecalis displayed a more reserved strategy, potentially downregulating metabolic activity, transcription, and translation in response to cohabitation with E. coli. Both E. coli and E. faecalis displayed significant downregulation of virulence-associated proteins when coexisting in dual-species biofilms. By delving deeper into these dynamics, we can gain a more comprehensive understanding of challenging biofilm-associated infections, paving the way for novel strategies to combat them.}, }
@article {pmid39884474, year = {2025}, author = {Ghosh, S and Kar, P and Chakraborty, PS and Pradhan, S and Chakrabarti, S and Ghosh, K}, title = {Characterization and anti-biofilm potentiality of an isolated novel Aeromonas hydrophila-infecting bacteriophage AHPMCC11, belonging to the genus Ahphunavirus.}, journal = {Microbial pathogenesis}, volume = {200}, number = {}, pages = {107344}, doi = {10.1016/j.micpath.2025.107344}, pmid = {39884474}, issn = {1096-1208}, abstract = {Aeromonas hydrophila is a major aquatic habitat pathogen responsible for huge economic losses in the aquaculture and food industries. In this study, a lytic bacteriophage AHPMCC11 was isolated by using A. hydrophila MTCC 1739. AHPMCC11 showed a short latent period of 10 min and the burst size was 215 PFU/cell. AHPMCC11 had potent bacteriolytic activity within 2 h in liquid culture inhibition assay and exhibited biofilm scavenging activity against A. hydrophila MTCC 1739. AHPMCC11 was found stable at a wide range of pH levels (3-12), temperature ranges (4-37 °C), and salinity conditions (0-40 ppt). The AHPMCC11 genome was determined to be 42,439 bp in length with 58.9 % G + C content, 51 CDS, and no tRNA. Comparative genome study suggested that AHPMCC11 may represent a novel species within the Autographiviridae family, belonging to the Ahphunavirus genus. In conclusion, AHPMCC11 might be used as a biocontrol agent in aquaculture and the food industry.}, }
@article {pmid39884207, year = {2025}, author = {Yesankar, PJ and Qureshi, A}, title = {Insights into the functionality of biofilm-forming bacterial consortia as bioavailability enhancers towards biodegradation of pyrene in hydrocarbon-contaminated soil.}, journal = {Journal of environmental management}, volume = {375}, number = {}, pages = {124295}, doi = {10.1016/j.jenvman.2025.124295}, pmid = {39884207}, issn = {1095-8630}, mesh = {*Biofilms ; *Biodegradation, Environmental ; *Soil Pollutants/metabolism ; *Pyrenes/metabolism ; *Soil Microbiology ; Soil/chemistry ; Hydrocarbons/metabolism ; Bacteria/metabolism/genetics ; Polycyclic Aromatic Hydrocarbons/metabolism ; }, abstract = {Hydrophobic organic compounds (HOCs), such as pyrene, pose significant challenges for microbial-based remediation in soil due to limited substrate availability and the sustainability of augmented microbes. Research targets are to investigate the potential of biofilm-forming bacterial cells to enhance pyrene bioavailability and biodegradation in two different hydrocarbon-contaminated soil microcosms, employing microbiological, molecular, and chemical analysis validated through statistical tools. The microcosm augmented with strong biofilm bacterial consortia (A) significantly enhanced pyrene availability by 1-1.5% compared to the weak biofilm consortia (B) and mixed consortia (AB). Analysis of 16 S rDNA amplicons revealed notable differences in bacterial community composition between consortia A and B augmented soil, with Proteobacteria as the dominant phylum. Taxonomic composition of soil microbiome predicted enhanced xenobiotic biodegradative potential of strong biofilm consortia (A) up to 20 days, exhibiting a higher abundance of functional genes related to upstream degradative pathway of PAHs, such as naphthalene dioxygenase (nahAa), PAH dioxygenase subunit genes (nidA, nidB), extradiol dioxygenase (phdF) and aldehyde dehydrogenase (nidD). Our study highlights the significant role of biofilm-forming bacteria as "bioavailability enhancers," for high molecular weight PAHs like pyrene, in contaminated soils with their implications for designing future sustainable bioremediation programs.}, }
@article {pmid39884024, year = {2025}, author = {Xia, C and Liu, R and Zhang, S and Shen, J and Wang, Z}, title = {Fluconazole-induced changes in azole resistance and biofilm production in Candida glabrata in vitro.}, journal = {Diagnostic microbiology and infectious disease}, volume = {111}, number = {3}, pages = {116683}, doi = {10.1016/j.diagmicrobio.2025.116683}, pmid = {39884024}, issn = {1879-0070}, abstract = {Currently, the molecular mechanisms of azole resistance in C. glabrata are unresolved. This study aims to detect azole resistance of C. glabrata after exposure to fluconazole (Diflucan) in vitro. After 50 days of induction, the five susceptible isolates of C. glabrata demonstrated cross-resistance to azoles (fluconazole (Diflucan), voriconazole and itraconazole). Mutations in PDR1 or ERG11 genes are key nodes in azole resistance of C. glabrata. DNA-Sequencing revealed three(3/5) fluconazole (Diflucan)-resistant isolates had undergone missense mutations (R376Q, R772K, E1083K in PDR1 and F135L in ERG11), all of which were newly discovered and previously unreported. mRNA expression of resistant genes in five resistant isolated was elevated, with CDR1 being the most prominent. Analysis using flow cytometry revealed that resistant strains showed decreased R6G uptake and increased efflux efficiency, but no obvious significance difference in biofilm production. C. glabrata acquires azole cross-resistance upon continuous exposed to fluconazole (Diflucan) and could remain resistant without antifungal agents. The development of azole resistance in C. glabrata has been linked to genes associated with efflux pump transporters and the ergosterol synthesis pathway. However, the relationship between resistance and newly discovered missense mutation sites requires further investigation.}, }
@article {pmid39881994, year = {2024}, author = {Tuan, DA and Uyen, PVN and Khuon, NV and Binh, LA and Masak, J}, title = {Innovative antifungal strategies: enhanced biofilm inhibition of Candida albicans by a modified tea tree oil formulation.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1518598}, pmid = {39881994}, issn = {1664-302X}, abstract = {INTRODUCTION: Candida albicans is a significant human pathogen with the ability to form biofilms, a critical factor in its resistance to antifungal treatments. This study aims to evaluate the antifungal activity and biofilm inhibition potential of Tea Tree Oil (TTO) derived from Melaleuca alternifolia cultivated in Vietnam.<br><br>METHODS: The antifungal activity of TTO was assessed by determining the Minimum Inhibitory Concentration (MIC), Minimum Fungicidal Concentration (MFC), Minimum Biofilm Inhibitory Concentration (MBIC), and Minimum Biofilm Eradication Concentration (MBEC) using broth dilution methods. The experiments were conducted on C. albicans in both planktonic and biofilm states across concentrations ranging from 0.1 &#x3bc;L/mL to 10 &#x3bc;L/mL.<br><br>RESULTS: TTO demonstrated significant antifungal efficacy, with a MIC of 0.1 &#x3bc;L/mL (&#x223c;91.217 &#x3bc;g/mL) and an MFC of 10 &#x3bc;L/mL (&#x223c;9121.7 &#x3bc;g/mL). It effectively inhibited biofilm formation with a recorded MBIC of 2 &#x3bc;L/mL (&#x223c;1824.34 &#x3bc;g/mL). However, MBEC values were not determinable as the concentrations tested did not achieve the eradication of more than 50% of mature biofilm within the experimental conditions.<br><br>DISCUSSION: These findings highlight TTO as a promising natural antifungal agent with strong biofilm-inhibitory properties. However, its limited efficacy in eradicating mature biofilms underscores the need for further studies, potentially involving higher concentrations or synergistic combinations with conventional antifungal agents.}, }
@article {pmid39881110, year = {2025}, author = {Riahi, A and Mabudi, H and Tajbakhsh, E and Roomiani, L and Momtaz, H}, title = {Correction: Optimizing chitosan derived from Metapenaeus affinis: a novel anti-biofilm agent against Pseudomonas aeruginosa.}, journal = {AMB Express}, volume = {15}, number = {1}, pages = {17}, pmid = {39881110}, issn = {2191-0855}, }
@article {pmid39880834, year = {2025}, author = {Xue, Y and Kang, X}, title = {Time-resolved compositional and dynamics analysis of biofilm maturation and dispersal via solid-state NMR spectroscopy.}, journal = {NPJ biofilms and microbiomes}, volume = {11}, number = {1}, pages = {21}, pmid = {39880834}, issn = {2055-5008}, support = {92478104//National Natural Science Foundation of China/ ; }, mesh = {*Biofilms/growth &amp; development ; *Bacillus subtilis/physiology/chemistry ; *Magnetic Resonance Spectroscopy/methods ; *Bacterial Proteins/metabolism/genetics/chemistry ; Polysaccharides, Bacterial/metabolism/chemistry ; Time Factors ; }, abstract = {Dispersal plays a crucial role in the development and ecology of biofilms. While extensive studies focused on elucidating the molecular mechanisms governing this process, few have characterized the associated temporal changes in composition and structure. Here, we employed solid-state nuclear magnetic resonance (NMR) techniques to achieve time-resolved characterization of Bacillus subtilis biofilms over a 5-day period. The mature biofilm, established within 48 h, undergoes significant degradation in following 72 h. The steepest decline of proteins precedes that of exopolysaccharides, likely reflecting their distinct spatial distribution. Exopolysaccharide sugar units display clustered temporal patterns, suggesting the presence of distinct polysaccharide types. A sharp rise in aliphatic carbon signals on day 4 probably corresponds to a surge in biosurfactant production. Different dynamic regimes respond differently to dispersal: the mobile domain exhibits increased rigidity, while the rigid domain remains stable. These findings provide novel insights and perspectives on the complex process of biofilm dispersal.}, }
@article {pmid39880641, year = {2025}, author = {Liaqat, I and Ibtisam, R and Hussain, MI and Muhammad, N and Andleeb, S and Naseem, S and Ali, A and Latif, AA and Ali, S and Aftab, MN and Bibi, A and Khalid, A}, title = {Medicinal Plants Exhibited Promising Potential to Inhibit Biofilm Formation by Catheter-Associated Bacteria in UTI Patients from Lahore, Pakistan.}, journal = {Journal of oleo science}, volume = {74}, number = {2}, pages = {221-232}, doi = {10.5650/jos.ess24212}, pmid = {39880641}, issn = {1347-3352}, mesh = {*Biofilms/drug effects ; *Plant Extracts/pharmacology ; Pakistan ; *Anti-Bacterial Agents/pharmacology/isolation &amp; purification ; *Plants, Medicinal/chemistry ; Humans ; *Trigonella/chemistry ; *Staphylococcus aureus/drug effects ; *Urinary Tract Infections/microbiology/drug therapy ; Pseudomonas aeruginosa/drug effects ; Ipomoea/chemistry ; Nigella sativa/chemistry ; Oils, Volatile/pharmacology/chemistry ; Thymus Plant/chemistry ; Klebsiella pneumoniae/drug effects ; Proteus mirabilis/drug effects ; Catheter-Related Infections/microbiology/prevention &amp; control/drug therapy ; Microbial Sensitivity Tests ; Dose-Response Relationship, Drug ; }, abstract = {The current study was designed to evaluate the antibacterial, antibiofilm, and biofilm inhibitory potential of six medicinal plants, including Trachyspermum ammi, Trigonella foenum-graecum, Nigella sativa, Thymus vulgaris, Terminalia arjuna, and Ipomoea carneaid against catheter-associated bacteria (CAB). Eighteen CAB were identified up to species level using 16S rRNA gene sequencing, viz., Klebsiella pneumoniae, Staphylococcus aureus, and Pseudomonas aeruginosa. T. ammi essential oil and T. foenum-graecum methanolic extract combination exhibited the highest antibacterial activity (ZOI; 32.0) against S. aureus. N. sativa essential oil (EO) showed highest ZOI (31.0; p ≤ 0.05) against Proteus mirabilis at 100 µgmL [-1] . Among 18 CAB isolated, 13 showed mature biofilm formation on 5 [th] day. All plant extracts demonstrated more than 80% antibiofilm and biofilm inhibition activity. A concentrationdependent increase was observed with plant extracts against CAB during antibacterial, antibiofilm, and biofilm inhibition activities. The study suggests that EO and methanolic extract (ME) of tested plants possess promising antibiofilm and biofilm inhibitory potential against CABs. To our knowledge, this is the first study to report antibacterial, antibiofilm, and biofilm inhibitory potential of T. ammi and N. sativa seed EO, as well as T. foenum-graecum, N. sativa, T. vulgaris, T. arjuna, and I. carnea ME against CAB from medical setting.}, }
@article {pmid39880334, year = {2025}, author = {Zhang, JT and Wang, JX and Liu, Y and Wang, JH and Chi, ZY}, title = {Effects of stratified microbial extracellular polymeric substances on microalgae dominant biofilm formation and nutrients turnover under batch and semi-continuous operation.}, journal = {Bioresource technology}, volume = {420}, number = {}, pages = {132120}, doi = {10.1016/j.biortech.2025.132120}, pmid = {39880334}, issn = {1873-2976}, abstract = {Extracellular polymeric substances (EPS) are well-acknowledged to accelerate microalgal biofilm formation, yet specific role of stratified EPS is unknown. Bacterial biofilm stratified EPS could enrich phosphorus, whether microalgal biofilm stratified EPS could also realize phosphorus or nitrogen enrichment remains unclarified. This study investigated microalgae dominant biofilm growth characteristics and nutrients removal via inoculating microalgae and stratified bacterial EPS at various microalgae:bacteria ratios. Soluble-EPS favored biofilm establishment and chlorophyll synthesis, while loosely-bound (LB-EPS) and tightly-bound EPS (TB-EPS) improved phosphorus removal, and optimum microalgae:bacteria cell count ratio was 1:0.5. Under semi-continuous operation, stable and efficient nutrients removal was observed at hydraulic retention time (HRT) of 2 days. Both nitrogen and phosphorus enrichment by TB-EPS over LB-EPS (respectively up to 7.9 and 23.8 times) were innovatively discovered, with enhanced nutrients turnover efficiency at higher HRTs. This study provided direct evidences regarding the role of stratified EPS on microalgal biofilm development and nutrients turnover.}, }
@article {pmid39879107, year = {2025}, author = {Akter, S and Rahman, MA and Ashrafudoulla, M and Mahamud, AGMSU and Chowdhury, MAH and Ha, SD}, title = {Mechanistic and bibliometric insights into RpoS-mediated biofilm regulation and its strategic role in food safety applications.}, journal = {Critical reviews in food science and nutrition}, volume = {}, number = {}, pages = {1-15}, doi = {10.1080/10408398.2025.2458755}, pmid = {39879107}, issn = {1549-7852}, abstract = {Biofilm, complex structures formed by microorganisms within an extracellular polymeric matrix, pose significant challenges in the sector by harboring dangerous pathogens and complicating decontamination, thereby increasing the risk of foodborne illnesses. This article provides a comprehensive review of the sigma factor, rpoS's role in biofilm development, specifically in gram-negative bacteria, and how the genetic, environmental, and regulatory elements influence rpoS activity with its critical role in bacterial stress responses. Our findings reveal that rpoS is a pivotal regulator of biofilm formation, enhancing bacterial survival in adverse conditions. Key factors affecting rpoS activity include oxidative and osmotic stress and nutrient availability. Understanding rpoS-mediated regulatory pathways is essential for developing targeted biofilm management strategies to improve food quality and safety. Furthermore, a bibliometric analysis highlights significant research trends and gaps in the literature, guiding future research directions. Future research should focus on detailed mechanistic studies of rpoS-mediated biofilm regulation, the development of specific rpoS inhibitors, and innovative approaches like biofilm-resistant surface coatings. This knowledge can lead to more effective contamination prevention and overall food safety enhancements.}, }
@article {pmid39878825, year = {2025}, author = {Pereira, DFGS and Nietsche, S and Xavier, AA and Mercadante-Simões, MO and Pereira, MCT}, title = {Biofilm formation by the plant growth promoting bacterium Bacillus cereus (EB-40).}, journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]}, volume = {}, number = {}, pages = {}, pmid = {39878825}, issn = {1678-4405}, abstract = {The objective of this work was to investigate the biofilm production capacity of the isolate EB-40 (Bacillus cereus) in a culture medium for the multiplication of microorganisms and in roots of in vitro grown banana explants. It was observed that the isolate was able to produce biofilms in tryptone, soy and agar (TSA) culture medium and in the roots of explants. The format, architecture and location of the biofilms in TSA culture medium presented an exopolymer matrix formed by EB-40 presented coccoid bacillary cells and fibrillar structures. In roots explants was verified the formation of microcolonies adhered to the root hairs. The information obtained in this experiment allowed inferring the ability of the isolate to produce biofilms and the colonization pattern shown when associated with banana tree roots.}, }
@article {pmid39878466, year = {2025}, author = {Fung, BL and Visick, KL}, title = {LitR and its quorum-sensing regulators modulate biofilm formation by Vibrio fischeri.}, journal = {Journal of bacteriology}, volume = {}, number = {}, pages = {e0047624}, doi = {10.1128/jb.00476-24}, pmid = {39878466}, issn = {1098-5530}, abstract = {Quorum sensing controls numerous processes ranging from the production of virulence factors to biofilm formation. Biofilms, communities of bacteria that are attached to one another and/or a surface, are common in nature, and when they form, they can produce a quorum of bacteria. One model system to study biofilms is the bacterium Vibrio fischeri, which forms a biofilm that promotes the colonization of its symbiotic host. Many factors promote V. fischeri biofilm formation in vitro, including the symbiosis polysaccharide (SYP) and cellulose, but the role of quorum sensing is currently understudied. Recently, a quorum-sensing-dependent transcription factor, LitR, was shown to negatively influence V. fischeri biofilm formation in the context of a biofilm-overproducing strain. To better understand the importance of LitR, we identified conditions in which the impact of LitR on biofilm formation could be observed in an otherwise wild-type strain and then investigated its role and the roles of upstream quorum regulators in biofilm phenotypes. In static conditions, LitR and its upstream quorum regulators, including autoinducer synthases LuxS and AinS, contributed to control over biofilms that were both SYP and cellulose dependent. In shaking liquid conditions, LitR and AinS contributed to control over biofilms that were primarily cellulose dependent. LitR modestly inhibited cellulose transcription in a manner that depended on the transcription factor VpsR. These findings expand our understanding of LitR and the quorum-sensing pathway in the physiology of V. fischeri and illuminate negative control mechanisms that prevent robust biofilm formation by wild-type V. fischeri under laboratory conditions.IMPORTANCEQuorum sensing is a key regulatory mechanism that controls diverse phenotypes in numerous bacteria, including Vibrio fischeri. In many microbes, quorum sensing has been shown to control biofilm formation, yet in V. fischeri, the link between quorum sensing and biofilm formation has been understudied. This study fills that knowledge gap by identifying roles for the quorum sensing-controlled transcription factor, LitR, and its upstream quorum-sensing regulators, including the autoinducer synthases AinS and LuxS, in inhibiting biofilm formation under specific conditions. It also determined that LitR inhibits the transcription of genes required for cellulose biosynthesis. This work thus expands our understanding of the complex control over biofilm regulation.}, }
@article {pmid39877654, year = {2024}, author = {Kulig, K and Wronowska, E and Juszczak, M and Zawrotniak, M and Karkowska-Kuleta, J and Rapala-Kozik, M}, title = {Host cell responses to Candida albicans biofilm-derived extracellular vesicles.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1499461}, pmid = {39877654}, issn = {2235-2988}, mesh = {*Extracellular Vesicles/metabolism ; *Candida albicans/physiology/pathogenicity ; *Biofilms/growth &amp; development ; Humans ; Animals ; *Macrophages/microbiology/immunology ; *Host-Pathogen Interactions ; *Cytokines/metabolism ; Epithelial Cells/microbiology ; THP-1 Cells ; Phagocytosis ; Candidiasis/microbiology/immunology ; A549 Cells ; Cell Line ; Larva/microbiology ; }, abstract = {Candida albicans is a prevalent fungal pathogen responsible for infections in humans. As described recently, nanometer-sized extracellular vesicles (EVs) produced by C. albicans play a crucial role in the pathogenesis of infection by facilitating host inflammatory responses and intercellular communication. This study investigates the functional properties of EVs released by biofilms formed by two C. albicans strains-3147 (ATCC 10231) and SC5314-in eliciting host responses. We demonstrate the capability of C. albicans EVs to trigger reactions in human epithelial and immune cells. The involvement of EVs in pathogenesis was evidenced from the initial stages of infection, specifically in adherence to epithelial cells. We further established the capacity of these EVs to induce cytokine production in the epithelial A549 cell line, THP-1 macrophage-like cells, and blood-derived monocytes differentiated into macrophages. Internalization of EVs by THP-1 macrophage-like cells was confirmed, identifying macropinocytosis and phagocytosis as the most probable mechanisms, as demonstrated using various inhibitors that target potential vesicle uptake pathways in human cells. Additionally, C. albicans EVs and their cargo were identified as chemoattractants for blood-derived neutrophils. After verification of the in vivo effect of biofilm-derived EVs on the host, using Galleria mellonella larvae as an alternative model, it was demonstrated that vesicles from C. albicans SC5314 increased mortality in the injected larvae. In conclusion, for both types of EVs a predominantly pro-inflammatory effect on host was observed, highlighting their significant role in the inflammatory response during C. albicans infection.}, }
@article {pmid39875714, year = {2025}, author = {Sağsöz, NP and Güven, L and Gür, B and Sezer, CV and Cengiz, M and Orhan, F and Barış, &#xd6;}, title = {Different essential oils can inhibit Candida albicans biofilm formation on acrylic resin by suppressing aspartic proteinase: In vitro and in silico approaches.}, journal = {Clinical oral investigations}, volume = {29}, number = {2}, pages = {94}, pmid = {39875714}, issn = {1436-3771}, mesh = {*Oils, Volatile/pharmacology ; *Candida albicans/drug effects ; *Biofilms/drug effects ; *Aspartic Acid Proteases/antagonists &amp; inhibitors ; *Gas Chromatography-Mass Spectrometry ; *Polymethyl Methacrylate/chemistry ; *Acrylic Resins/chemistry/pharmacology ; Cymbopogon/chemistry ; Antifungal Agents/pharmacology ; In Vitro Techniques ; Syzygium/chemistry ; Computer Simulation ; Mice ; Microbial Sensitivity Tests ; }, abstract = {INTRODUCTION: Cymbopogon martini, Syzygium aromaticum, and Cupressus sempervirens are used for antimicrobial purposes in the worldwide. Both their extracts and essential oil contents are rich in active ingredients.<br><br>OBJECTIVE: The aim of this study was to investigate the inhibitory effect of Cymbopogon martini essential oil (CMEO), Syzygium aromaticum essential oil (SAEO) and Cupressus sempervirens essential oil (CSEO) on Candida albicans biofilm formation on heat-polymerized polymethyl methacrylate (PMMA) samples in vitro and in silico.<br><br>MATERIALS AND METHODS: Essential oil contents with anticandidal potential were determined by Gas Chromatography-Mass Spectrometry. Following C. albicans adhesion, PMMA samples were treated independently with Corega[&#xae;] and each essential oil. The anticandidal activity of the essential oils was determined by spectrophotometric absorbance measurement at 600&#xa0;nm, taking into account the cultures of each sample. The cytotoxicity evaluation of essential oils was performed by MTT Colorimetric assay. The software package AutoDockTools (1.5.6) was used for the in silico studies. The effect of essential oil content on the inhibition of Secreted aspartic proteinase (SAP2) was evaluated considering the Ligand@SAP2 complex formation.<br><br>RESULTS: 2% of CMEO and 5% of SAEO exhibited higher anticandidal activity than Corega[&#xae;] (p&#x2009;<&#x2009;0.05), whereas Corega[&#xae;] had higher anticandidal activity than 2% and 5% of CSEO (p&#x2009;<&#x2009;0.05). The cytotoxicity of essential oils on NIH/3T3 cells after 24&#xa0;h was found to be 2.41 for CSEO, 2.84 for CMEO, and 2.85&#xa0;&#xb5;g/mL for SAEO. The results of the in silico study showed that citronellol from CMEO, chavibetol (m-eugenol) from SAEO and &#x3b2;-pinene from CSEO each had the highest effect on the inhibition of SAP2. The highest binding affinity value was found for citronellol at -5.3&#xa0;kcal/mol.<br><br>CONCLUSIONS: The biofilm formation of C. albicans onto acrylic resin was inhibited by CMEO, SAEO and CSEO at a concentration of 2% through in vitro assay. The most effective inhibition was determined to be due to citronellol in CMEO through in silico analysis.}, }
@article {pmid39873514, year = {2025}, author = {Mundodi, V and Choudhary, S and Smith, AD and Kadosh, D}, title = {Ribosome profiling reveals differences in global translational vs transcriptional gene expression changes during early Candida albicans biofilm formation.}, journal = {Microbiology spectrum}, volume = {}, number = {}, pages = {e0219524}, doi = {10.1128/spectrum.02195-24}, pmid = {39873514}, issn = {2165-0497}, abstract = {Candida albicans, a major human fungal pathogen, can form biofilms on a variety of inert and biological surfaces. C. albicans biofilms allow for immune evasion, are highly resistant to antifungal therapies, and represent a significant complication for a wide variety of immunocompromised patients in clinical settings. While transcriptional regulators and global transcriptional profiles of C. albicans biofilm formation have been well-characterized, much less is known about translational regulation of this important C. albicans virulence property. Here, using ribosome profiling, we define the first global translational profile of genes that are expressed during early biofilm development in a human fungal pathogen, C. albicans. We show that C. albicans biofilm formation involves altered translational regulation of genes and gene classes associated with protein synthesis, pathogenesis, transport, plasma membrane, polarized growth, cell cycle, secretion, and signal transduction. Interestingly, while similar, but not identical, classes of genes showed transcriptional alterations during early C. albicans biofilm development, we observed very little overlap between specific genes that are upregulated or downregulated at the translational vs transcriptional levels. Our results suggest that distinct translational mechanisms play an important role in regulating early biofilm development of a major human fungal pathogen. These mechanisms, in turn, could serve as potential targets for novel antifungal strategies.IMPORTANCEThe major human fungal pathogen Candida albicans is known to form biofilms or complex aggregated microbial communities encased in an extracellular matrix. These biofilms allow C. albicans to escape detection by the immune system as well as resist a variety of antifungal drugs. In this study, we define the first global profile of genes that show altered translation during C. albicans biofilm formation. These genes are involved in a variety of key cellular processes, including polarized growth, pathogenesis, transport, protein synthesis, cell cycle, plasma membrane, signal transduction, and secretion. Interestingly, while similar classes of genes are induced at both the transcriptional and translational levels during early C. albicans biofilm formation, we observed very little overlap among specific genes with altered transcription and translation. Our results suggest that C. albicans biofilm formation is controlled by distinct translational mechanisms, which could potentially be targeted by novel antifungal drugs.}, }
@article {pmid39873503, year = {2025}, author = {Albano, C and Nabawy, A and Tran, WC and Prithviraj, M and Kado, T and Hassan, MA and Makabenta, JMV and Rotello, VM and Morita, YS}, title = {Effective killing of Mycobacterium abscessus biofilm by nanoemulsion delivery of plant phytochemicals.}, journal = {Microbiology spectrum}, volume = {}, number = {}, pages = {e0216624}, doi = {10.1128/spectrum.02166-24}, pmid = {39873503}, issn = {2165-0497}, abstract = {UNLABELLED: Mycobacterium is an acid-fast, aerobic, non-motile, and biofilm-forming bacterium. The increasing prevalence of mycobacterial infections makes it necessary to find new methods to combat the resistance of bacteria to conventional antibiotics. Mycobacterium abscessus is an emerging pathogen that is intrinsically drug resistant due to several factors, including an impermeable cell envelope, drug efflux pumps, target-modifying enzymes, and the ability to form thick, robust biofilms. Phytochemicals are promising antimicrobials; however, their poor solubility in water and their inability to penetrate biofilms render them inefficient in killing bacterial biofilms. In this study, we demonstrate the efficacy of polymer-stabilized phytochemical nanoemulsions in killing M. abscessus biofilms. These nanoemulsions improve the solubility and stability of the phytochemicals and enable biofilm penetration and eradication. We show that the phytochemical emulsions effectively eliminated M. abscessus in an in vitro biofilm model and killed non-replicating persister cells in the Wayne hypoxia model. These nanoemulsions were also effective in vivo in a wound infection model. These findings demonstrate the potential of polymer-stabilized phytochemical nanoemulsions as a promising alternative to conventional antibiotics for the treatment of mycobacterial infections.<br><br>IMPORTANCE: Mycobacterium abscessus is among the opportunistic bacterial pathogens that cause nontuberculous mycobacterial diseases. The infection caused by M. abscessus is difficult to treat because the bacterium is resistant to many of the currently available antibiotics, limiting chemotherapeutic strategies. Furthermore, it forms biofilms in clinically relevant settings, making the infection difficult to treat. Many phytochemicals have potent antimicrobial activities, but their hydrophobicity limits clinical applications. In this study, we tested a new drug delivery strategy where hydrophobic plant phytochemicals were emulsified with a biodegradable nanosponge. We show that the emulsification makes phytochemicals such as carvacrol and eugenol more effective against M. abscessus biofilms. We further demonstrate that nanoemulsified phytochemicals can kill hypoxia-induced dormant M. abscessus and effectively improve skin wound infection in mice. Our data pave the way to use phytochemical nanosponge as a platform to create synergy by combining other antimycobacterial drugs.}, }
@article {pmid39871625, year = {2025}, author = {Schandl, S and Osondu-Chuka, G and Guagliano, G and Perak, S and Petrini, P and Briatico-Vangosa, F and Reimhult, E and Guillaume, O}, title = {Acetylation of alginate enables the production of inks that mimic the chemical properties of P. aeruginosa biofilm.}, journal = {Journal of materials chemistry. B}, volume = {}, number = {}, pages = {}, pmid = {39871625}, issn = {2050-7518}, abstract = {The reason why certain bacteria, e.g., Pseudomonas aeruginosa (PA), produce acetylated alginate (Alg) in their biofilms remains one of the most intriguing facts in microbiology. Being the main structural component of the secreted biofilm, like the one formed in the lungs of cystic fibrosis (CF) patients, Alg plays a crucial role in protecting the bacteria from environmental stress and potential threats. Nonetheless, to investigate the PA biofilm environment and its lack of susceptibility to antibiotic treatment, the currently developed in vitro biofilm models use native seaweed Alg, which is a non-acetylated Alg. The role of the acetyl side group on the backbone of bacterial Alg has never been elucidated, and the transposition of experimental results obtained from such systems to clinical conditions (e.g., to treat CF-infection) may be hazardous. We systematically investigated the influence of acetylation on the physico-chemical and mechanical properties of Alg in solution and Ca[2+]-crosslinked hydrogels. Furthermore, we assessed how the acetylation influenced the interaction of Alg with tobramycin, a common aminoglycoside antibiotic for PA. Our study revealed that the degree of acetylation directly impacts the viscosity and Young's Modulus of Alg in a pH-dependent manner. Acetylation increased the mesh size in biofilm-like Alg hydrogels, directly influencing antibiotic penetration. Our results provide essential insights to create more clinically relevant in vitro infection models to test the efficacy of new drugs or to better understand the 3D microenvironment of PA biofilms.}, }
@article {pmid39871438, year = {2025}, author = {Guo, N and Wang, S and Whitfield, CT and Batchelor, WD and Wang, Y and Blersch, D and Higgins, BT and Feng, Y and Liles, MR and de-Bashan, LE and Wang, Y and Ma, Y}, title = {High-Efficiency CRISPR-Cas9 Genome Editing Unveils Biofilm Insights and Enhances Antimicrobial Activity in Bacillus velezensis FZB42.}, journal = {Biotechnology and bioengineering}, volume = {}, number = {}, pages = {}, doi = {10.1002/bit.28933}, pmid = {39871438}, issn = {1097-0290}, support = {//National Institute of Food and Agriculture./ ; }, abstract = {Bacillus velezensis FZB42 is a prominent plant growth-promoting rhizobacterium and biocontrol agent known for producing a wide array of antimicrobial compounds. The capability to genetically manipulate this strain would facilitate understanding its metabolism and enhancing its sustainable agriculture applications. In this study, we report the first successful implementation of high-efficiency CRISPR-Cas9 genome editing in B. velezensis FZB42, enabling targeted genetic modifications to gain insights into its plant growth-promotion and biocontrol properties. Deletion of the slrR gene, a key regulator of biofilm formation, resulted in significant alterations in biofilm structure and development, as demonstrated by scanning electron microscopy and quantitative biofilm assays. These findings provide valuable insights into the mechanisms of biofilm formation, which are critical for root colonization and plant growth promotion. Additionally, we overexpressed the bac gene cluster responsible for bacilysin biosynthesis by replacing its native promoter with the strong constitutive promoter P43 and integrating an additional copy of the bacG gene. This genetic manipulation led to a 2.7-fold increase in bacB gene expression and significantly enhanced antibacterial activity against Escherichia coli and Lactobacillus diolivorans. The successful implementation of the CRISPR-Cas9 system for genome editing in FZB42 provides a valuable tool for genetic engineering, with the potential to improve its biocontrol efficacy and broaden its applications in agriculture and other biotechnology areas. Our principles and procedures are broadly applicable to other agriculturally significant microorganisms.}, }
@article {pmid39871158, year = {2025}, author = {Varin-Simon, J and Colin, M and Velard, F and Tang-Fichaux, M and Ohl, X and Mongaret, C and Gangloff, SC and Reffuveille, F}, title = {Correction: Cutibacterium acnes biofilm formation is influenced by bone microenvironment, implant surfaces and bacterial internalization.}, journal = {BMC microbiology}, volume = {25}, number = {1}, pages = {48}, pmid = {39871158}, issn = {1471-2180}, }
@article {pmid39868561, year = {2025}, author = {de Almeida, VF and Urzêdo, JE and Velikkakam, T and Alves Moreira, GPC and da Fonseca, SCR and Bastos, CM and Royer, S and Dias, VL and Almeida Junior, ER and Martins Aires, CA and Maciel, MAV and Ferro Cavalcanti, IM and Gontijo-Filho, PP and Ribas, RM}, title = {Effector genes of type III secretion system and biofilm formation in virulent Pseudomonas aeruginosa isolates carrying bla KPC-2 and bla PDC-5 genes in hospital environment.}, journal = {Journal of medical microbiology}, volume = {74}, number = {1}, pages = {}, doi = {10.1099/jmm.0.001956}, pmid = {39868561}, issn = {1473-5644}, mesh = {*Biofilms/growth &amp; development ; *Pseudomonas aeruginosa/genetics/isolation &amp; purification/pathogenicity/physiology ; *beta-Lactamases/genetics/metabolism ; Humans ; *Bacterial Proteins/genetics/metabolism ; *Type III Secretion Systems/genetics/metabolism ; *Pseudomonas Infections/microbiology ; Brazil ; Hospitals ; Drug Resistance, Multiple, Bacterial/genetics ; Anti-Bacterial Agents/pharmacology ; Carbapenems/pharmacology ; Virulence/genetics ; Genotype ; }, abstract = {Introduction. In critically ill patients, the occurrence of multidrug-resistant Pseudomonas aeruginosa infection is a significant concern, given its ability to acquire multidrug-resistant, form biofilms and secrete toxic effectors.Hypothesis or Gap Statement. In Brazil, limited data are available regarding the prevalence of dissemination, and the impact of the type III secretion system (T3SS) on toxin production and biofilm formation in clinical isolates of P. aeruginosa.Aim. This study investigates the dissemination of virulent P. aeruginosa harbouring the bla KPC-2 and bla PDC-5 genes, the presence of T3SS genes and their biofilm-forming capability.Methodology. A total of 128 non-duplicate clinical isolates of carbapenem-resistant P. aeruginosa (CRPA) from different sources collected from eight hospitals were examined. Detection was performed by PCR of the T3SS genes (exoU, exoT, exoS and exoY), carbapenemases (bla KPC, bla GIM and bla NDM) and beta-lactamase gene (bla PDC). PFGE and phenotypic biofilm production (initial adhesion assay and biofilm cell concentration) were performed.Results. We found exoT[+] (86%) to be the most frequent genotypic variant, followed by exoY[+] (61%). Notably, a substantial proportion of isolates exhibited the simultaneous presence of exoU[+] and exoS[+] genes, along with a high prevalence of bla KPC-2 [+] (64%) and bla PDC-5 [+] (64%) among the disseminated clones in the evaluated region. Additionally, 78% of the isolates demonstrated biofilm-forming capability, and two distinct clonal profiles were identified and disseminated both intra- and inter-hospital. Also, it was revealed that the exoU genotype was significantly more frequent among multidrug-resistant strains.Conclusion. These findings underscore the ability of multiple virulent and biofilm-producing clones of CRPA to propagate effectively.}, }
@article {pmid39868500, year = {2025}, author = {Li, G and Chen, W and Guan, H and Lai, Z and Shao, C and AnshanShan, }, title = {Dendritic Antifungal Peptides as Potent Agents against Drug-Resistant Candida albicans and Biofilm.}, journal = {Journal of medicinal chemistry}, volume = {}, number = {}, pages = {}, doi = {10.1021/acs.jmedchem.4c02598}, pmid = {39868500}, issn = {1520-4804}, abstract = {Candida albicans infection is a major public health problem, exacerbated by the emergence of drug-resistant fungi with the widespread use of antifungal drugs. Therefore, the development of novel antifungal drugs for drug-resistant C. albicans infections is crucial. We constructed a series of dendritic antifungal peptides (AFPs) with different chain lengths of fatty acids as hydrophobic ends and 2 or 3 protease-stable repeats (Arg-Pro) as dendritic peptide branches. Among them, C4-3RP exhibited excellent antidrug-resistant fungal and biofilm activity (GMall = 5.04 μM) and was nontoxic. Furthermore, C4-3RP demonstrated high protease stability and salt ion tolerance, making it highly effective in murine skin infection mediated by C. albicans. In addition, C4-3RP uses multiple mechanisms of action to achieve excellent antifungal effects. In conclusion, the construction of dendritic peptides holds substantial potential in the treatment of fungal infections and provides a broader perspective on the design of peptide-based antifungal drugs.}, }
@article {pmid39867469, year = {2024}, author = {Zorzetto, L and Hammer, S and Paris, S and Bidan, CM}, title = {In vitro model of bacterial biofilm mineralization in complex humid environments: a proof of concept study.}, journal = {Frontiers in bioengineering and biotechnology}, volume = {12}, number = {}, pages = {1496117}, pmid = {39867469}, issn = {2296-4185}, abstract = {BACKGROUND: Bacteria in physiological environments can generate mineralizing biofilms, which are associated with diseases like periodontitis or kidney stones. Modelling complex environments presents a challenge for the study of mineralization in biofilms. Here, we developed an experimental setup which could be applied to study the fundamental principles behind biofilm mineralization on rigid substrates, using a model organism and in a tailored bioreactor that mimics a humid environment. We developed a simple yet effective method to produce rigid specimens with the desired shape.<br><br>MATERIALS AND METHODS: To simulate humid growth conditions, rigid specimens were conditioned with human saliva, inoculated with the chosen model bacterial strain and placed in a chamber with continuous drop-wise supply of nutritious media. The preconditioning stage did not affect significantly the bacteria proliferation, but considering this option was instrumental to future evolutions of the model, where saliva could be substituted with other substances (e.g., urine, plasma or antimicrobial solutions). Two different growth media were used: a control medium with nutritious substances and a mineralizing medium consisting in control medium supplemented with mineral precursors. Both the specimen shape and the bioreactor designs resulted from an optimization process thoroughly documented in this work. As a proof of concept, we showed that it is possible to locate the bacteria and minerals using confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM).<br><br>RESULTS: We achieved an in vitro model representative of the conditions of growth and mineralization of biofilms in humid environments on a rigid substrate: something between the traditional solid-air and solid-liquid interface models.<br><br>CONCLUSION: Such model will be useful to understand fundamental mechanisms happening in complex environments.}, }
@article {pmid39866782, year = {2025}, author = {Su, J and Wu, Y and Wang, Z and Zhang, D and Yang, X and Zhao, Y and Yu, A}, title = {Probiotic biofilm modified scaffolds for facilitating osteomyelitis treatment through sustained release of bacteriophage and regulated macrophage polarization.}, journal = {Materials today. Bio}, volume = {30}, number = {}, pages = {101444}, pmid = {39866782}, issn = {2590-0064}, abstract = {Osteomyelitis has gradually become a catastrophic complication in orthopedic surgery due to the formation of bacterial biofilms on the implant surface and surrounding tissue. The therapeutic challenges of antibiotic resistance and poor postoperative osseointegration provide inspiration for the development of bioactive implants. We have strategically designed bioceramic scaffolds modified with Lactobacillus reuteri (LR) and bacteriophages (phages) to achieve both antibacterial and osteogenic effects. Leveraging the tendency of bacteria to adhere to the surface of implants, bioceramics have been modified with LR biofilm to promote bone repair. The LR biofilm, sterilized by pasteurization, prevents sepsis caused by live bacteria and is biocompatible with phages. Phages, being natural enemies of bacteria, not only effectively kill bacteria and inhibit biofilm formation but also readily adsorb onto the surface of bioceramics. Hence, this scaffold, loaded with a phage cocktail, lysates specific bacterial populations, namely Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). More importantly, the inactivated LR biofilm stimulates macrophages RAW264.7 to polarize towards an anti-inflammatory M2 phenotype, creating an immune microenvironment favorable for inducing osteogenic differentiation of rat mesenchymal stem cells in vitro. In a rat model of infectious cranial defects, the scaffold not only effectively eliminated S. aureus and alleviated associated inflammation but also mediated macrophage-mediated immunoregulation, thus resulting in effective osteogenesis. Collectively, these multifunctional modified scaffolds offer an integrated approach to both bacterium elimination and bone repair, presenting a new strategy for bioactive implants in the clinical management of osteomyelitis.}, }
@article {pmid39866403, year = {2025}, author = {Saberi, Y and Halaji, M and Karami, M and Jafarzadeh, J and Javadi, K and Shirafkan, H and Pournajaf, A}, title = {Antimicrobials profiling, biofilm formation, and clonal lineage of methicillin-resistant Staphylococcus aureus isolated from cockroaches.}, journal = {Heliyon}, volume = {11}, number = {1}, pages = {e41698}, pmid = {39866403}, issn = {2405-8440}, abstract = {Cockroaches are widely recognized as vectors for transmitting pathogenic microorganisms in hospital and community environments due to their movement between contaminated and human-occupied spaces. Staphylococcus aureus (S. aureus), particularly methicillin-resistant Staphylococcus aureus (MRSA), is a primary global health concern because of its capacity to cause a wide range of infections and its resistance to many antibiotics. Despite efforts to control nosocomial infections, the role of cockroaches in disseminating antibiotic-resistant bacteria has not been fully explored. This study aims to investigate the antibiotic resistance patterns, biofilm formation, and genetic characteristics of S. aureus isolated from cockroaches in hospital environments. Understanding the role of cockroaches as vectors of drug-resistant S. aureus can contribute to developing more effective infection control strategies in healthcare settings. This study examined 386 cockroaches, including 230 American and 156 German cockroaches. Antibiotic sensitivity, inducible resistance, and biofilm formation were evaluated. The presence of mecA, ermA, ermB, ermC, msrA, icaA, icaB, icaC, icaD, SCCmec, mupA, mupB, and iles-1 genes was determined. Randomly amplified polymorphic DNA typing was performed to determine genetic relatedness. Fifty S. aureus isolates were identified, with 48 % confirmed as MRSA. No isolate exhibited constitutive resistance to clindamycin. However, 96 % of the isolates displayed inducible clindamycin resistance (iMLSB phenotype) when tested using the D-test. The prevalence of icaA, icaB, icaC, and icaD genes were 34 %, 8 %, 0 %, and 0 %, respectively. So, 29.1 %, 16.6 %, 12.5 %, and 8.3 % of isolates had SCCmec gene cassettes of types I, II, III, and IV, respectively. The prevalence of ermA, ermB, ermC, and msrA genes was found to be 18 %, 16 %, 58 %, and 4 %, respectively. Seven different clusters were found in the RAPD-PCR, with cluster A (5 isolates) being the most common. These results show that cockroaches are important in transmitting resistance factors as mechanical vectors. Therefore, taking sanitary measures to control the insect population is unavoidable.}, }
@article {pmid39865215, year = {2025}, author = {Amod, A and Anand, AA and Sahoo, AK and Samanta, SK}, title = {Diagnostic and therapeutic strategies in combating implanted medical device-associated bacterial biofilm infections.}, journal = {Folia microbiologica}, volume = {}, number = {}, pages = {}, pmid = {39865215}, issn = {1874-9356}, abstract = {Bacterial biofilms exhibit remarkable resistance against conventional antibiotics and are capable of evading the humoral immune response. They account for nearly 80% of chronic infections in humans. Development of bacterial biofilms on medical implants results in their malfunctioning and subsequently leads to high mortality rates worldwide. Therefore, early and precise diagnosis of bacterial biofilms on implanted medical devices is essential to prevent their failure and associated complications. Culture-based methods are time consuming, more prone to contamination and often exhibit low sensitivity. Different molecular, imaging, and physical methods can aid in more accurate and faster detection of implant-associated bacterial biofilms. Biofilm growth on implant surface can be prevented either through modification of the implant material or by application of different antibacterial coatings on implant surface. Experimental studies have shown that pre-existing biofilms from medical implants can be removed by breaking down biofilm matrix, utilizing physical methods, nanomaterials and antimicrobial peptides. The current review delves into mechanism of biofilm formation on implanted medical devices and the subsequent host immune response. Much emphasis has been laid on different ongoing diagnostic and therapeutic strategies to achieve improved patient outcomes and reduced socio-economic burden.}, }
@article {pmid39864903, year = {2025}, author = {Sowmeya, VG and Sathiavelu, M}, title = {Biofilm dynamics in space and their potential for sustainable space exploration - A comprehensive review.}, journal = {Life sciences in space research}, volume = {44}, number = {}, pages = {108-121}, doi = {10.1016/j.lssr.2024.08.006}, pmid = {39864903}, issn = {2214-5532}, mesh = {*Biofilms/growth &amp; development ; *Space Flight ; Weightlessness ; Extraterrestrial Environment ; }, abstract = {Microbial biofilms are universal. The intricate tapestry of biofilms has remarkable implications for the environment, health, and industrial processes. The field of space microbiology is actively investigating the effects of microgravity on microbes, and discoveries are constantly being made. Recent evidence suggests that extraterrestrial environments also fuel the biofilm formation. Understanding the biofilm mechanics under microgravitational conditions is crucial at this stage and could have an astounding impact on inter-planetary missions. This review systematically examines the existing understanding of biofilm development in space and provides insight into how molecules, physiology, or environmental factors influence biofilm formation during microgravitational conditions. In addition, biocontrol strategies targeting the formation and dispersal of biofilms in space environments are explored. In particular, the article highlights the potential benefits of using microbial biofilms in space for bioremediation, life support systems, and biomass production applications.}, }
@article {pmid39863912, year = {2025}, author = {O'Brien, PA and Bell, SC and Rix, L and Turnlund, AC and Kjeldsen, SR and Webster, NS and Negri, AP and Abdul Wahab, MA and Vanwonterghem, I}, title = {Light and dark biofilm adaptation impacts larval settlement in diverse coral species.}, journal = {Environmental microbiome}, volume = {20}, number = {1}, pages = {11}, pmid = {39863912}, issn = {2524-6372}, abstract = {BACKGROUND: Recovery of degraded coral reefs is reliant upon the recruitment of coral larvae, yet the mechanisms behind coral larval settlement are not well understood, especially for non-acroporid species. Biofilms associated with reef substrates, such as coral rubble or crustose coralline algae, can induce coral larval settlement; however, the specific biochemical cues and the microorganisms that produce them remain largely unknown. Here, we assessed larval settlement responses in five non-acroporid broadcast-spawning coral species in the families Merulinidae, Lobophyllidae and Poritidae to biofilms developed in aquaria for either one or two months under light and dark treatments. Biofilms were characterised using 16S rRNA gene sequencing to identify the taxa associated with settlement induction and/or inhibition.<br><br>RESULTS: We show that light and biofilm age are critical factors in the development of settlement inducing biofilms, where different biofilm compositions impacted larval settlement behaviour. Further, we show that specific biofilm taxa were either positively or negatively correlated with coral settlement, indicating potential inducers or inhibitors. Although these taxa were generally specific to each coral species, we observed bacteria classified as Flavobacteriaceae, Rhodobacteraceae, Rhizobiaceae and Pirellulaceae to be consistently correlated with larval settlement across multiple coral species.<br><br>CONCLUSIONS: Our work identifies novel microbial groups that significantly influence coral larval settlement, which can be targeted for the discovery of settlement-inducing metabolites for implementation in reef restoration programs. Furthermore, our results reinforce that the biofilm community on coral reef substrates plays a crucial role in influencing coral larval recruitment, thereby impacting the recovery of coral reefs.}, }
@article {pmid39863195, year = {2025}, author = {Liu, XF and Wang, P and Dong, Z and Zu, Y and Wang, X and Zhai, Y and Wudong, G and Yang, Y and Hao, M and Zhou, D and Liu, W and Jin, YP and Wang, AH}, title = {(P)ppGpp synthetase Rel facilitates cellulose formation of biofilm by regulating glycosyltransferase in Brucella abortus.}, journal = {International journal of biological macromolecules}, volume = {302}, number = {}, pages = {140022}, doi = {10.1016/j.ijbiomac.2025.140022}, pmid = {39863195}, issn = {1879-0003}, abstract = {Biofilms are complex adhesive structures that establish chronic infection and allow robust protection from external stressors such as antibiotics. Cellulose as one of the compositions of bacteria biofilm which protect bacteria from stress, host immune responses and resistance to antibiotics. Bacterial stress responses are regulated via guanosine pentaphosphate and tetraphosphate (p)ppGpp. This molecule has been a target of research efforts to counteract biofilm formation in pathogenic bacteria. However, a role for (p)ppGpp synthetase Rel influencing in biofilms and its cellulose formation has not been identified in Brucella. Firstly, rel mutant significantly decreased biofilm biomass and rendered biofilms more susceptible to most antibiotics. The rel mutant also showed greatly decreased biofilm architectures including exopolysaccharide, extracellular DNA, and lipid. Remarkably, we found rel mutant significantly decreased biofilm cellulose formation. We further combined proteomic analysis to explore the key proteins involved in cellulose regulation of Rel in Brucella biofilm formation. 287 differentially expressed proteins (DEPs) were identified and enriched in diverse metabolic pathway between WT and Δrel strains including purine and sulfur metabolism, transcription factors and glycosyltransferases which may be related to cellulose formation. The Q-PCR showed that mRNA levels of only glycosyltransferase (WP_006161578.1) of the 12 down-DFPs had significantly upregulated in rel mutant contrast to WT strain and β-galactosidase assay showed a negative regulatory in rel mutant. Furthermore, Rel-dependent biofilms cellulose was also restored and accompanied by an increase in glycosyltransferase (WP_006161578.1) when glucose was added in TSB medium. Overall, this work expands the role of (p)ppGpp synthetase Rel as an important regulator in biofilm and cellulose formation that is tightly linked with pathogenicity and chronic persistent infections in Brucella.}, }
@article {pmid39863090, year = {2025}, author = {Che, J and Liu, B and Fang, Q and Nissa, MU and Luo, T and Wang, L and Bao, B}, title = {Biological studies reveal the role of trpA gene in biofilm formation, motility, hemolysis and virulence in Vibrio anguillarum.}, journal = {Microbial pathogenesis}, volume = {200}, number = {}, pages = {107331}, doi = {10.1016/j.micpath.2025.107331}, pmid = {39863090}, issn = {1096-1208}, abstract = {Vibrio anguillarum is a pathogen responsible for vibriosis in aquaculture animals. The formation of bacterial biofilm contributes to infections and increases resistance to antibiotics. Tryptophanase and its substrate tryptophan have been recognized as signal molecules regulating bacterial biofilm formation. This study aimed to investigate the role of the trpA gene encoding tryptophan synthase in V. anguillarum through constructing a trpA mutant (ΔtrpA) and its complemented strain (CΔtrpA). The ΔtrpA produced less tryptophan compared to the WT and ΔtrpA strains, with almost no detectable indole synthesis in the ΔtrpA mutant. RNAseq analysis showed that 152 genes were differentially expressed in the ΔtrpA mutant, including 64 upregulated and 88 downregulated genes. KEGG enrichment analysis and qRT-PCR validation indicated that genes associated with bacterial chemotaxis, two component system, quorum sensing and biofilm formation were downregulated. Crystal violet staining confirmed that the ΔtrpA mutant decreased biofilm formation due to the reduced tryptophan and indole. Our studies also showed that TrpA plays an important role in the motility and hemolytic ability of V. anguillarum. Finally, the virulence of the ΔtrpA mutant was evaluated using a Tetrahymena infection model, which demonstrated that the virulence of ΔtrpA mutant was significantly attenuated. These findings provide insight into the role of trpA gene in biofilm formation, motility, hemolysis, and virulence in V. anguillarum.}, }
@article {pmid39861155, year = {2025}, author = {Hanot, M and Lohou, E and Sonnet, P}, title = {Anti-Biofilm Agents to Overcome Pseudomonas aeruginosa Antibiotic Resistance.}, journal = {Pharmaceuticals (Basel, Switzerland)}, volume = {18}, number = {1}, pages = {}, pmid = {39861155}, issn = {1424-8247}, support = {no number//Minist&#xe8;re de l'Education Sup&#xe9;rieure et de la Recherche/ ; }, abstract = {Pseudomonas aeruginosa is one of world's most threatening bacteria. In addition to the emerging prevalence of multi-drug resistant (MDR) strains, the bacterium also possesses a wide variety of virulence traits that worsen the course of the infections. Particularly, its ability to form biofilms that protect colonies from antimicrobial agents is a major cause of chronic and hard-to-treat infections in immune-compromised patients. This protective barrier also ensures cell growth on abiotic surfaces and thus enables bacterial survival on medical devices. Hence, as the WHO alerted to the need to develop new treatments, the use of anti-biofilm agents (ABAs) appeared as a promising approach. Given the selection pressure imposed by conventional antibiotics, a new therapeutic strategy has emerged that aims at reducing bacterial virulence without inhibiting cell growth. So-called anti-virulence agents (AVAs) would then restore the efficacy of conventional antibiotics (ATBs) or potentiate the effectiveness of the immune system. The last decade has seen the development of ABAs as AVAs against P. aeruginosa. This review aims to highlight the design strategy and critical features of these molecules to pave the way for further discoveries of highly potent compounds.}, }
@article {pmid39861020, year = {2025}, author = {Trinchera, M and Midiri, A and Mancuso, G and Lagrotteria, MA and De Ani, CA and Biondo, C}, title = {A Four-Year Study of Antibiotic Resistance, Prevalence and Biofilm-Forming Ability of Uropathogens Isolated from Community- and Hospital-Acquired Urinary Tract Infections in Southern Italy.}, journal = {Pathogens (Basel, Switzerland)}, volume = {14}, number = {1}, pages = {}, pmid = {39861020}, issn = {2076-0817}, mesh = {Humans ; *Urinary Tract Infections/microbiology/epidemiology/drug therapy ; *Biofilms/drug effects/growth &amp; development ; *Cross Infection/microbiology/epidemiology ; Retrospective Studies ; *Community-Acquired Infections/microbiology/epidemiology ; Italy/epidemiology ; *Anti-Bacterial Agents/pharmacology ; *Drug Resistance, Bacterial ; Prevalence ; Microbial Sensitivity Tests ; Female ; Male ; Middle Aged ; Aged ; Adult ; Bacteria/drug effects/isolation &amp; purification ; }, abstract = {The aim of this study was to investigate the differences between nosocomial and community microorganisms isolated from patients with UTI by determining their bacterial profile, antibiotic resistance and ability to produce biofilms. A retrospective study, based on bacterial isolates from consecutive urine samples collected between January 2019 and December 2023, was conducted at a university hospital. The main pathogens isolated from both community and hospital samples were the same, but their frequency of isolation differed. Compared with community-associated cases, hospital-associated infections have more isolates of Acinetobacter baumanii complex. In contrast, Proteus mirabilis isolates were more prevalent in community than in hospital infections. In both hospital and community isolates, gram-positive bacteria showed a lower overall antimicrobial resistance (22%) compared to gram-negative bacteria (30%). The data demonstrated that individual strains exhibited disparate degrees of capacity for biofilm formation. Additionally, the data indicate an inverse correlation between biofilm production and antibiotic resistance. Isolates from community patients exhibited lower capacities for biofilm production in comparison to the capacities demonstrated by microorganisms isolated from nosocomial patients (29% and 35%, respectively). Area-specific surveillance studies can provide valuable information on UTI pathogens and antimicrobial resistance patterns, which can be useful in guiding empirical treatment.}, }
@article {pmid39860971, year = {2024}, author = {Spiegel, C and Coraça-Huber, DC and Nogler, M and Arora, R and Putzer, D}, title = {Cold Plasma Activity Against Biofilm Formation of Prosthetic Joint Infection Pathogens.}, journal = {Pathogens (Basel, Switzerland)}, volume = {14}, number = {1}, pages = {}, pmid = {39860971}, issn = {2076-0817}, support = {6318442//FFG Agency/ ; }, mesh = {*Biofilms/growth &amp; development ; *Plasma Gases/pharmacology ; *Prosthesis-Related Infections/microbiology ; Humans ; *Staphylococcus aureus/physiology ; *Staphylococcus epidermidis/physiology ; Staphylococcal Infections/microbiology ; Bacterial Load/drug effects ; Argon/pharmacology ; Joint Prosthesis/adverse effects/microbiology ; }, abstract = {Periprosthetic joint infections occur in 1-2% of all patients undergoing prosthetic joint surgeries. Although strong efforts have been made to reduce infection rates, conventional therapies like one- or two-stage revisions have failed to lower the infection rates. Cold atmospheric plasma (CAP) has shown promising results in reducing bacterial loads on surfaces. In this study, we aimed to investigate the ability of CAP to reduce the bacterial load on metal surfaces with varying distances and different plasma compositions below a temperature suitable for in vivo applications. Methods: Biofilm was formed with Staphylococcus aureus ATCC 29213 and Staphylococcus epidermidis ATCC 12228 cultures on TMZF discs. Plasma treatments using air plasma and argon plasma were conducted on discs containing the established biofilm while the temperature was measured. During the experiments, the duration and the distance of plasma application varied. Afterwards, colony-forming units were counted. Results: The results of this study showed that air and argon plasma could be considered for applications during surgeries at a 1 cm distance. While air plasma showed the highest efficiency in CFU reduction, the temperature generation due to the presence of oxygen poses a limitation concerning the duration of application. The use of argon as a plasma generator does not show the temperature limitation in correlation to exposure time. The use of air plasma with a distance of 1 cm to the application site and an exposure time of 5 s showed the most effective bacterial reduction while not exceeding tissue-damaging temperatures.}, }
@article {pmid39859989, year = {2025}, author = {Azeem, K and Fatima, S and Ali, A and Ubaid, A and Husain, FM and Abid, M}, title = {Biochemistry of Bacterial Biofilm: Insights into Antibiotic Resistance Mechanisms and Therapeutic Intervention.}, journal = {Life (Basel, Switzerland)}, volume = {15}, number = {1}, pages = {}, pmid = {39859989}, issn = {2075-1729}, abstract = {Biofilms, composed of structured communities of bacteria embedded in a self-produced extracellular matrix, pose a significant challenge due to their heightened resistance to antibiotics and immune responses. This review highlights the mechanisms underpinning antibiotic resistance within bacterial biofilms, elucidating the adaptive strategies employed by microorganisms to withstand conventional antimicrobial agents. This encompasses the role of the extracellular matrix, altered gene expression, and the formation of persister cells, contributing to the recalcitrance of biofilms to eradication. A comprehensive understanding of these resistance mechanisms provides a for exploring innovative therapeutic interventions. This study explores promising avenues for future research, emphasizing the necessity of uncovering the specific genetic and phenotypic adaptations occurring within biofilms. The identification of vulnerabilities in biofilm architecture and the elucidation of key biofilm-specific targets emerge as crucial focal points for the development of targeted therapeutic strategies. In addressing the limitations of traditional antibiotics, this review discusses innovative therapeutic approaches. Nanomaterials with inherent antimicrobial properties, quorum-sensing inhibitors disrupting bacterial communication, and bacteriophages as biofilm-specific viral agents are highlighted as potential alternatives. The exploration of combination therapies, involving antimicrobial agents, biofilm-disrupting enzymes, and immunomodulators, is emphasized to enhance the efficacy of existing treatments and overcome biofilm resilience.}, }
@article {pmid39859390, year = {2025}, author = {Caldara, M and Bolhuis, H and Marmiroli, M and Marmiroli, N}, title = {Biofilm Formation, Modulation, and Transcriptomic Regulation Under Stress Conditions in Halomicronema sp.}, journal = {International journal of molecular sciences}, volume = {26}, number = {2}, pages = {}, pmid = {39859390}, issn = {1422-0067}, support = {818431//European Union/ ; }, mesh = {*Biofilms/growth &amp; development ; *Gene Expression Regulation, Bacterial ; *Transcriptome ; *Stress, Physiological ; Cyanobacteria/genetics/metabolism ; Bacterial Proteins/metabolism/genetics ; Gene Expression Profiling ; Antioxidants/metabolism ; }, abstract = {In nature, bacteria often form heterogeneous communities enclosed in a complex matrix known as biofilms. This extracellular matrix, produced by the microorganisms themselves, serves as the first barrier between the cells and the environment. It is composed mainly of water, extracellular polymeric substances (EPS), lipids, proteins, and DNA. Cyanobacteria form biofilms and have unique characteristics such as oxygenic photosynthesis, nitrogen fixation, excellent adaptability to various abiotic stress conditions, and the ability to secrete a variety of metabolites and hormones. This work focused on the characterization of the cyanobacterium Halomicronema sp. strain isolated from a brackish environment. This study included microscopic imaging, determination of phenolic content and antioxidant capacity, identification of chemicals interfering with biofilm formation, and transcriptomic analysis by RNA sequencing and real-time PCR. Gene expression analysis was centered on genes related to the production of EPS and biofilm-related transcription factors. This study led to the identification of wza1 and wzt as EPS biomarkers and luxR-05665, along with genes belonging to the TetR/AcrR and LysR families, as potential biomarkers useful for studying and monitoring biofilm formation under different environmental conditions. Moreover, this work revealed that Halomicronema sp. can grow even in the presence of strong abiotic stresses, such as high salt, and has good antioxidant properties.}, }
@article {pmid39859320, year = {2025}, author = {Fydrych, D and Jeziurska, J and Wełna, J and Kwiecińska-Piróg, J}, title = {Potential Use of Selected Natural Compounds with Anti-Biofilm Activity.}, journal = {International journal of molecular sciences}, volume = {26}, number = {2}, pages = {}, pmid = {39859320}, issn = {1422-0067}, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Phytochemicals/pharmacology/chemistry ; Humans ; Biological Products/pharmacology/chemistry ; Quorum Sensing/drug effects ; Bacteria/drug effects ; Animals ; }, abstract = {Antibiotic resistance in microorganisms is an escalating global concern, exacerbated by their formation of biofilms, which provide protection through an extracellular matrix and communication via quorum sensing, enhancing their resistance to treatment. This situation has driven the search for alternative approaches, particularly those using natural compounds. This study explores the potential of phytochemicals, such as quercetin, apigenin, arbutin, gallic acid, proanthocyanidins, and rutin, known for their antibacterial properties and ability to inhibit biofilm formation and disrupt mature biofilms. The methods used in this study included a comprehensive review of current literature assessing the bioavailability, distribution, and effective concentrations of these compounds in treating biofilm-associated infections. The results indicate that these phytochemicals exhibit significant antibacterial effects, reduce biofilm's structural integrity, and inhibit bacterial communication pathways. Moreover, their potential use in combination with existing antibiotics may enhance therapeutic outcomes. The findings support the conclusion that phytochemicals offer promising additions to anti-biofilm strategies and are capable of complementing or replacing conventional treatments, with appropriate therapeutic levels and delivery mechanisms being key to their effectiveness. This insight underscores the need for further research into their clinical applications for treating infections complicated by biofilms.}, }
@article {pmid39858927, year = {2025}, author = {Iliev, I and Yahubyan, G and Apostolova-Kuzova, E and Gozmanova, M and Mollova, D and Iliev, I and Ilieva, L and Marhova, M and Gochev, V and Baev, V}, title = {Characterization and Probiotic Potential of Levilactobacillus brevis DPL5: A Novel Strain Isolated from Human Breast Milk with Antimicrobial Properties Against Biofilm-Forming Staphylococcus aureus.}, journal = {Microorganisms}, volume = {13}, number = {1}, pages = {}, pmid = {39858927}, issn = {2076-2607}, support = {BG-RRP-2.004-0001-C01//European Union-NextGenerationEU, through the National Recovery and Resilience Plan of the Republic of Bulgaria/ ; }, abstract = {Lactobacillus is a key genus of probiotics commonly utilized for the treatment of oral infections The primary aim of our research was to investigate the probiotic potential of the newly isolated Levilactobacillus brevis DPL5 strain from human breast milk, focusing on its ability to combat biofilm-forming pathogens such as Staphylococcus aureus. Employing in vitro approaches, we demonstrate L. brevis DPL5's ability to endure at pH 3 with survival rates above 30%, and withstand the osmotic stress often found during industrial processes like fermentation and freeze drying, retaining over 90% viability. The lyophilized cell-free supernatant of L. brevis DPL5 had a significant antagonistic effect against biofilm-producing nasal strains of Staphylococcus aureus, and it completely eradicated biofilms at subinhibitory concentrations of 20 mg·mL[-1]. Higher concentrations of 69 mg·mL[-1] were found to have a 99% bactericidal effect, based on the conducted probability analysis, indicating the production of bactericidal bioactive extracellular compounds capable of disrupting the biofilm formation of pathogens like S. aureus. Furthermore, genome-wide sequencing and analysis of L. brevis DPL5 with cutting-edge Nanopore technology has uncovered over 50 genes linked to probiotic activity, supporting its ability to adapt and thrive in the harsh gut environment. The genome also contains multiple biosynthetic gene clusters such as lanthipeptide class IV, Type III polyketide synthase (T3PKS), and ribosomally synthesized, and post-translationally modified peptides (RiPP-like compounds), all of which are associated with antibacterial properties. Our study paves the way for the further exploration of DPL5, setting the stage for innovative, nature-inspired solutions to combat stubborn bacterial infections.}, }
@article {pmid39858865, year = {2025}, author = {Zhang, Y and Li, K and Ru, Y and Ma, Y}, title = {Biofilm Compositions and Bacterial Diversity on Kitchen Towels in Daily Use.}, journal = {Microorganisms}, volume = {13}, number = {1}, pages = {}, pmid = {39858865}, issn = {2076-2607}, support = {22CGA55//Shanghai Municipal Education Commission/ ; 22PJ1411600//Science and Technology Commission of Shanghai Municipality/ ; 32202205//National Natural Science Foundation of China/ ; }, abstract = {Towels with complex woven structures are susceptible to biofilm formation during daily use. The composition of biofilms formed on towels used under real-life conditions has yet to be studied. Thus, we investigated the color changes, structural integrity, and biofilm development on towels used continuously for 10 weeks by 12 volunteers in specific kitchen environments. Apparent biofilms composed of bacteria and extracellular polymeric substances (EPSs) were found on all used towels. The bacteria concentrations ranged from 4 to 7 log CFU/g. Proteins were the most abundant EPS, followed by polysaccharides and eDNA. A high-throughput sequencing method was employed to investigate the bacterial diversity on the towels. The predominant bacterial genera differed from towel to towel. Kocuria, Rothia, Psychrobacter, Enhydrobacter, and Pseudomonas are genera of relatively high abundance that may originate from the human body and foods. In addition, correlations among environmental factors, major bacterial genera, physical properties, and biofilm formation of the towels were analyzed, which could provide a scientific reference for maintaining towel hygiene.}, }
@article {pmid39858391, year = {2025}, author = {Ganić, T and Pećinar, I and Nikolić, B and Kekić, D and Tomić, N and Cvetković, S and Vuletić, S and Mitić-Ćulafić, D}, title = {Evaluation of Cinnamon Essential Oil and Its Emulsion on Biofilm-Associated Components of Acinetobacter baumannii Clinical Strains.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {14}, number = {1}, pages = {}, pmid = {39858391}, issn = {2079-6382}, abstract = {BACKGROUND/OBJECTIVES: Acinetobacter baumannii, one of the most dangerous pathogens, is able to form biofilm structures and aggravate its treatment. For that reason, new antibiofilm agents are in need, and new sources of antibiofilm compounds are being sought from plants and their products. Cinnamon essential oil is associated with a wide spectrum of biological activities, but with a further improvement of its physicochemical properties it could provide even better bioavailability. The aim of this work was the evaluation of the antibiofilm properties of cinnamon essential oil and its emulsion.<br><br>METHODS: In order to evaluate the antibiofilm activity, crystal violet assay was performed to determine biofilm biomass. The main components of the biofilm matrix were measured as well as the motile capacity of the tested strains. Gene expression was monitored with RT-qPCR, while treated biofilms were observed with Raman spectroscopy.<br><br>RESULTS: A particularly strong potential against pre-formed biofilm with a decreased biomass of up to 66% was found. The effect was monitored not only with regard to the whole biofilm biomass, but also on the individual components of the biofilm matrix such as exopolysaccharides, proteins, and eDNA molecules. Protein share drops in treated biofilms demonstrated the most consistency among strains and rose to 75%. The changes in strain motility and gene expressions were investigated after the treatments were carried out. Raman spectroscopy revealed the influence of the studied compounds on chemical bond types and the components present in the biofilm matrix of the tested strains.<br><br>CONCLUSIONS: The results obtained from this research are promising regarding cinnamon essential oil and its emulsion as potential antibiofilm agents, so further investigation of their activity is encouraged for their potential use in biomedical applications.}, }
@article {pmid39858345, year = {2025}, author = {Karthikeyan, A and Thirugnanasambantham, MK and Khan, F and Mani, AK}, title = {Bacteria-Inspired Synthesis of Silver-Doped Zinc Oxide Nanocomposites: A Novel Synergistic Approach in Controlling Biofilm and Quorum-Sensing-Regulated Virulence Factors in Pseudomonas aeruginosa.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {14}, number = {1}, pages = {}, pmid = {39858345}, issn = {2079-6382}, abstract = {Multidrug-resistant Pseudomonas aeruginosa infections pose a critical challenge to healthcare systems, particularly in nosocomial settings. This drug-resistant bacterium forms biofilms and produces an array of virulent factors regulated by quorum sensing. In this study, metal-tolerant bacteria were isolated from a metal-contaminated site and screened for their ability to synthesize multifunctional nanocomposites (NCs). Rapid color changes in the reaction solution evidenced the biotransformation process. The potent isolated Bacillus cereus SASAK, identified via 16S rRNA sequencing and deposited in GenBank under accession number MH885570, facilitated the microbial-mediated synthesis of ZnO nanoparticles and silver-doped ZnO NCs. These biogenic nanocomposites were characterized using UV-VIS-NIR spectroscopy, FTIR, XRD, zeta potential, HRTEM, FESEM, and EDX analyses. At a sub-MIC concentration of 100 µg/mL, 2% Ag-ZnO NCs effectively inhibited virulent factor production and biofilm formation in P. aeruginosa without affecting bacterial growth. Notably, there was a significant reduction in violacein pigment (96.25%), swarming motility, and pyocyanin concentration (1.87 µg/mL). Additionally, biofilm formation (81.1%) and EPS production (83.9%) using P. aeruginosa were substantially hindered, along with reduced extracellular protease activity, as indicated by zone formation (from 2.3 to 1.8 cm). This study underscores the potential of Ag-ZnO NCs as promising agents for combating quorum sensing-mediated virulence in chronic infections caused by multidrug-resistant P. aeruginosa.}, }
@article {pmid39858335, year = {2025}, author = {Paladini, F and Panico, A and Masi, A and Russo, F and Sannino, A and Pollini, M}, title = {Silver-Treated Sutures for the Prevention of Biofilm-Associated Surgical Site Infections.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {14}, number = {1}, pages = {}, pmid = {39858335}, issn = {2079-6382}, abstract = {BACKGROUND/OBJECTIVES: The huge concerns associated with biofilm-related infections in surgical procedures, along with the antibiotic resistance demonstrated by an increasing number of bacteria, have highlighted the need for alternative and effective prevention approaches. The aim of this research was to develop novel antimicrobial coatings on surgical sutures for the prevention of surgical site infections through nanotechnology-based methods.<br><br>RESULTS: The results demonstrated that although very low amounts of silver precursor were adopted for the treatments, the silver coating was effective against Staphylococcus aureus and antibiotic-resistant Pseudomonas aeruginosa in reducing the potential risk of infection.<br><br>METHODS: Nanostructured silver coatings were deposited onto the surface of polyglactin 910 absorbable braided sutures through a technology based on a photo-assisted chemical reaction. The materials were characterized in order to verify the efficacy of the coating in preventing biofilm formation and in reducing the bacterial colonization of the device.<br><br>CONCLUSIONS: As a broad-spectrum antimicrobial agent, silver represents an important option for the prevention and management of surgical site infections. The silver deposition technology adopted in this work provides an interesting strategy for preventing biofilm formation on medical devices such as surgical sutures.}, }
@article {pmid39858318, year = {2025}, author = {Rybak, B and Jarzembowski, T and Daca, A and Krawczyk, B and Piechowicz, L}, title = {Genetic Determinants and Biofilm Properties Useful in Estimation of UTI Pathogenicity of the Escherichia coli Strains Isolated from Free-Living Birds.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {14}, number = {1}, pages = {}, pmid = {39858318}, issn = {2079-6382}, abstract = {Background/Objectives: According to the One Health concept, wild birds can be indicators of ecosystem pollution and disease incidence. Escherichia coli strains are widespread worldwide, but there are still few reports on the association of human infections with a potential reservoir of highly pathogenic human strains in wild birds. Fecal E. coli with uropathogenic potential (UPEC) can be transmitted between birds and humans and may be a risk factor for urinary tract infections (UTIs). Results: The results showed that above 50% of the isolates were grouped as highly pathogenic, according to Clermont phylogroup classification. Such strains were found to be stronger biofilm producers, with a higher adherence of monocytes than low pathogenic. However, the highest cytotoxicity was observed for strains described as aquatic environmental. Convergence of the results of the analysis of monocyte activation by E. coli strains and the ability to form biofilm by individual phylogroups of the strains tested was demonstrated. Genetic determinants of the uropathogenicity of E. coli (UPEC) correlate with the evidence of strain pathogenicity during monocyte activation in in vitro assays. Methods: In this study, we assessed the virulence potential of environmental strains isolated from wild waterfowl using genetic analysis (Clermont phylogroup classification) and phenotypic methods, including analysis of the human monocyte response to biofilm formation. The estimation of the ability to form biofilms was tested using crystal violet, and the pathogenic potential of strains by monocyte activation assay including changes in morphology, adhesion and cytotoxicity. Conclusions: In conclusion, the virulence of E. coli strains isolated from free-living birds is significant, and they can be considered environmental reservoirs of pathogenic strains. According to our observations, they can be responsible for the dissemination of uropathogenic strains among humans.}, }
@article {pmid39858317, year = {2025}, author = {Facchin, A and Filipe, J and Mauri, I and Tagliasacchi, F and Grilli, G and Vitiello, T and Ratti, G and Musa, L and Penati, M and Scarpa, P and Lauzi, S}, title = {Antimicrobial Resistance and Biofilm-Forming Ability in ESBL-Producing and Non-ESBL-Producing Escherichia coli and Klebsiella pneumoniae Isolated from Canine Urinary Samples from Italy.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {14}, number = {1}, pages = {}, pmid = {39858317}, issn = {2079-6382}, support = {LINEA2_SLAUZ_2019_AA//University of Milan/ ; }, abstract = {Background: In dogs, bacterial urinary tract infections are a frequent cause of antimicrobial prescription, increasing the risk of selecting antibiotic-resistant bacteria. This study analyzed resistance patterns, the presence of extended-spectrum β-lactamases (ESBLs) and biofilm-forming capacity in E. coli and K. pneumoniae previously isolated from urine samples collected from 133 selected dogs admitted to the Veterinary Teaching Hospital of Milan, Italy, in 2021 and 2023. Methods: The E. coli and K. pneumoniae isolates were bacteriologically and genetically analyzed. Results: Overall, 53/133 (39.8%) samples had a positive microbiological culture. Thirty-four E. coli/K. pneumoniae isolates were detected, accounting for 26.5% of the examined samples. The 34 isolates included 28 E. coli and 6 K. pneumoniae. Four (11.8%) were ESBL-producing bacteria, all supported by blaCTX-M gene belonging to group 1. The K. pneumoniae isolates were significantly associated with ESBL production (p < 0.05). MIC analysis showed 11 (32.4%) multidrug-resistant isolates. Biofilm-forming capacity was observed in 23 (67.6%) isolates, regardless of bacterial species, including 20 weakly and 3 moderately adherent bacteria. All moderate biofilm producers were K. pneumoniae. Multidrug resistance (MDR) was significantly more present in strains with moderate biofilm-forming ability compared to strains with weak ability to form biofilm (p < 0.05). E. coli was confirmed as the most commonly identified urinary isolate in dogs. Conclusions: The high presence of ESBL producers and MDR in K. pneumoniae suggests mandatory in vitro susceptibility testing in the presence of this bacterium in dogs with UTI. The association of moderate biofilm production with MDR highlights the need for monitoring and surveillance of bacterial prevalence and resistance patterns of urinary isolates in dogs.}, }
@article {pmid39858312, year = {2025}, author = {de León Guerra, L and Padilla Montaño, N and Moujir, L}, title = {Interference of Celastrol with Cell Wall Synthesis and Biofilm Formation in Staphylococcus epidermidis.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {14}, number = {1}, pages = {}, pmid = {39858312}, issn = {2079-6382}, abstract = {Background: The emergence of antibiotic-resistant bacteria, including Staphylococcus epidermidis, underscores the need for novel antimicrobial agents. Celastrol, a natural compound derived from the plants of the Celastraceae family, has demonstrated promising antibacterial and antibiofilm properties against various pathogens. Objectives: This study aims to evaluate the antibacterial effects, mechanism of action, and antibiofilm activity of celastrol against S. epidermidis, an emerging opportunistic pathogen. Methods: To investigate the mechanism of action of celastrol, its antibacterial activity was evaluated by determining the time-kill curves, assessing macromolecular synthesis, and analysing its impact on the stability and functionality of the bacterial cell membrane. Additionally, its effect on biofilm formation and disruption was examined. Results: Celastrol exhibited significant antibacterial activity with a minimal inhibitory concentration (MIC) of 0.31 μg/mL and minimal bactericidal concentration (MBC) of 15 μg/mL, which is superior to conventional antibiotics used as control. Time-kill assays revealed a concentration-dependent bactericidal effect, with a shift from bacteriostatic activity at lower concentrations to bactericidal and lytic effect at higher concentrations. Celastrol inhibited cell wall biosynthesis by blocking the incorporation of N-acetylglucosamine (NAG) into peptidoglycan. In contrast, the cytoplasmic membrane was only affected at higher concentrations of the compound or after prolonged exposure times. Additionally, celastrol was able to disrupt biofilm formation at concentrations of 0.9 μg/mL and to eradicate pre-formed biofilms at 7.5 μg/mL in S. epidermidis. Conclusions: Celastrol exhibits significant antibacterial and antibiofilm activities against S. epidermidis, with a primary action on cell wall synthesis. Its efficacy in disrupting the formation of biofilms and pre-formed biofilms suggests its potential as a therapeutic agent for infections caused by biofilm-forming S. epidermidis resistant to conventional treatments.}, }
@article {pmid39858305, year = {2024}, author = {Kim, S and Kim, TJ}, title = {Inhibitory Effect of Moringa oleifera Seed Extract and Its Behenic Acid Component on Staphylococcus aureus Biofilm Formation.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {14}, number = {1}, pages = {}, pmid = {39858305}, issn = {2079-6382}, support = {P0012725//Korea Institute for Advancement of Technology/ ; }, abstract = {Background/Objectives: Inhibiting biofilm formation without killing cells facilitates the physical removal of contaminating bacteria while minimizing the opportunity for resistant bacteria to emerge. Results: The M. oleifera methanolic seed extract contained 1.48% behenic acid, significantly inhibiting S. aureus biofilm formation. Although behenic acid did not affect cell growth, it inhibited biofilm formation in a concentration-dependent manner, up to 20 mg/L. The cell physiology changes caused by behenic acid are potentially unrelated to biofilm formation inhibition, as no correlation was noted between cell hydrophobicity, polysaccharide production, extracellular DNA production, or protein production and behenic acid concentration. Thus, it was hypothesized that the surfactant properties of behenic acid contribute to its ability to inhibit biofilm formation, as a similar biofilm-inhibitory effect was observed when S. aureus was administered 1% Tween 80, a surfactant. Methods: A methanolic extract of Moringa oleifera seeds was selected from a library of edible plant extracts to inhibit Staphylococcus aureus biofilm formation without cell killing. Conclusions: Behenic acid is a saturated fatty acid that is used as an ingredient in cosmetics and ointments; thus, behenic acid may benefit the skin by inhibiting the biofilm formation of S. aureus, a commensal skin pathogen.}, }
@article {pmid39858289, year = {2024}, author = {Alluhaim, W and Alkhulaifi, MM and Alzahrani, RR and Alrfaei, BM and Yassin, AEB and Alghoribi, MF and Alsaadi, AM and Al-Asmari, AI and Al-Fahad, AJ and Ali, R and Alhawiti, NM and Halwani, MA}, title = {Effectiveness of a Novel Liposomal Methylglyoxal-Tobramycin Formulation in Reducing Biofilm Formation and Bacterial Adhesion.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {14}, number = {1}, pages = {}, pmid = {39858289}, issn = {2079-6382}, support = {RC20/109/R//King Abdullah International Research Center, National Guard Health Affairs, Riyadh, Saudi Arabia/ ; }, abstract = {Background: The emergence of multidrug-resistant bacteria presents a significant global health threat. Liposomal antibiotics have shown a potential to improve antibiotic delivery and efficacy. This study aimed to develop liposomes encapsulating tobramycin (TOB) and methylglyoxal (MGO) to enhance TOB activity while reducing bacterial adhesion and biofilm formation. Methods: Clinical isolates of Pseudomonas aeruginosa and Klebsiella pneumoniae were characterized using whole-genome sequencing. Liposomes (Lip-MGO-TOB) were formulated using Manuka honey as a surfactant and loaded with MGO and TOB. Antibacterial activity, biofilm formation, and bacterial cell adhesion assays were performed to compare the efficacy of Lip-MGO-TOB against free TOB. Liposome characterization included analyses of morphology, zeta potential, TOB encapsulation efficiency, and stability under various biological conditions. Results: The Lip-MGO-TOB formulation, at a minimum inhibitory concentration (MIC) of 32 µg/mL, reduced the biofilm formation of the P. aeruginosa isolate (PA85) by 68%. Conversely, free TOB, at a MIC of 64 µg/mL, achieved only a 21% reduction. For the K. pneumoniae isolate (KP57), Lip-MGO-TOB inhibited bacterial adhesion to A549 cells at a lower concentration (256 µg/mL) compared to free TOB (512 µg/mL). Lip-MGO-TOB demonstrated sustained drug release over 24 h under tested conditions and retained over 99% of TOB. Conclusions: The Lip-MGO-TOB formulation significantly enhanced TOB activity against resistant bacteria compared to free TOB. Additionally, it provided a stable drug delivery system with controlled drug release. Liposomal TOB represents a promising advancement in combating antibiotic resistance by improving the efficacy and delivery of conventional antibiotics.}, }
@article {pmid39856935, year = {2025}, author = {Vice, Z and Zhou, Y and Chitlapilly Dass, S and Wang, R}, title = {Microscopic Analysis of Temperature Effects on Surface Colonization and Biofilm Morphology of Salmonella enterica.}, journal = {Foods (Basel, Switzerland)}, volume = {14}, number = {2}, pages = {}, pmid = {39856935}, issn = {2304-8158}, support = {P20 GM113126/GM/NIGMS NIH HHS/United States ; }, abstract = {Salmonella enterica represents a diverse group of pathogens commonly associated with food contamination including red meat. Even though pre- and post-harvest cleaning and sanitization procedures are widely implemented at meat processing plants to mitigate the hazard, S. enterica cells may escape the process by colonizing, on contact, surfaces in the form of a biofilm that functions as an aggregated microbial community to facilitate mutual protection, antimicrobial resistance, proliferation and dissemination. Biofilm development is a complex process that can be affected by a variety of factors including environmental temperature. We developed methods using scanning electron microscopy and confocal microscopy with a novel image analysis software tool to investigate the temperature influence on S. enterica cell colonization and biofilm formation by directly visualizing and comparing the biofilm matrix's morphological differences under various temperatures. Cocktails of S. enterica strains belonging to serovars, commonly isolated from meat samples, were applied to develop biofilms on a stainless steel surface at 7, 15, or 37 °C. Results of the microscopy analysis showed that as temperature increased, better-defined biofilm structures with extracellular polymeric structures (EPS) could be identified. However, S. enterica colonization and aggregated bacterial biomass were clearly observed at the low temperature (7 °C) as well. These results demonstrate that the environmental temperature significantly contributes to S. enterica biofilm formation as the higher temperatures encourage bacterial active proliferation and biofilm maturation leading to the development of well-pronounced structures, while the lower temperature may promote cell attachment but, meanwhile, limit the EPS biosynthesis and biofilm maturation. Our study indicates that the mature S. enterica biofilms formed under favorable conditions may protect the pathogens with the well-developed 3-demensional (3D) structure against routine treatment. Furthermore, the low temperatures commonly maintained at meat plants are not able to effectively prevent S. enterica colonization and biofilm formation since at such temperatures there could still be colonized biomass that can contaminate the products. Therefore, the temperature effect on pathogen colonization and biofilm development should be taken into consideration while evaluating hygiene standards and sanitization procedures at the processing facilities.}, }
@article {pmid39856838, year = {2025}, author = {Wu, J and Yu, Y and Liu, F and Cao, Y and Ren, J and Fan, Y and Xiao, X}, title = {γ-Aminobutyric Acid (GABA) Metabolic Bypass Plays a Crucial Role in Stress Tolerance and Biofilm Formation in C. sakazakii ATCC 29544.}, journal = {Foods (Basel, Switzerland)}, volume = {14}, number = {2}, pages = {}, pmid = {39856838}, issn = {2304-8158}, support = {32172320//National Natural Science Foundation of China/ ; 2024M750951//China Postdoctoral Science Foundation/ ; 2024B03J1177//Guangzhou Science and Technology Plan Project/ ; GZC20230847//National funded postdoctoral researcher program of China/ ; }, abstract = {Cronobacter sakazakii is a foodborne pathogen characterized by its robust stress tolerance and ability to form biofilms, which facilitates its survival in powdered infant formula (PIF) processing environments for prolonged periods. Gamma-aminobutyric acid (GABA) is a kind of non-protein amino acid that acts as an osmoprotectant. This study aimed to elucidate the effects of the gabT gene on the survival of C. sakazakii, GABA accumulation, and biofilm formation under desiccation, osmotic stress, and acid exposure. A gabT knockout strain of C. sakazakii was developed using gene recombination techniques. The GABA content and survival rates of both the wild-type and knockout strains were compared under various stress conditions. Scanning electron microscopy (SEM) was used to observe cellular damage and biofilm formation. Statistical analysis was performed using a one-way analysis of variance (ANOVA). The deletion of gabT resulted in enhanced GABA accumulation under different stress conditions, improving the bacterium's tolerance to desiccation, osmotic pressure, and acid treatment. SEM images revealed that under identical stress conditions, the gabT knockout strain exhibited less cellular damage compared to the wild-type strain. Both strains were capable of biofilm formation under low osmotic pressure stress, but the gabT knockout strain showed higher GABA content, denser biofilm formation, and increased biofilm quantity. Similar trends were observed under acid stress conditions. The gabT gene plays a key role in modulating GABA accumulation, which enhances the stress tolerance and biofilm formation of C. sakazakii. These findings provide new insights into the role of GABA in bacterial survival mechanisms and highlight the potential for targeting GABA pathways to control C. sakazakii in food processing environments.}, }
@article {pmid39856776, year = {2025}, author = {El-Sayed, DS and Hassan, SS and Jassim, LS and Issa, AA and Al-Oqaili, F and Albayaty, MK and Hasoon, BA and Jabir, MS and Rasool, KH and Elbadawy, HA}, title = {Structural and topological analysis of thiosemicarbazone-based metal complexes: computational and experimental study of bacterial biofilm inhibition and antioxidant activity.}, journal = {BMC chemistry}, volume = {19}, number = {1}, pages = {24}, pmid = {39856776}, issn = {2661-801X}, abstract = {The structural and electronic behavior of thiosemicarbazone (TSC)-based metal complexes of Mn (II), Fe (II), and Ni (II) have been investigated. The synthesized metal complexes were characterized using elemental analysis, magnetic susceptibility, molar conductivity, FTIR, and UV-Vis spectroscopy, the computational path helped with further structural investigation. The solubility test on the TSC and its complexes revealed their solubility in most organic solvents. DFT computational analysis was performed, and quantum reactivity parameters of the octahedral optimized complexes were calculated to describe the reactivity via the stability states of the synthesized complexes. FMOs map was generated to confirm similar findings and MEP analysis was applied to elaborate the important electrophilic and nucleophilic sites on the studied surfaces. Also, other important topological analyses such as electron localization function and reduced density gradient, to establish the favorable noncovalent interactions, were studied. In silico molecular docking approach was studied against the gram-positive bacteria Bacillus cereus to predict the potent inhibition behavior of the studied complexes. The findings summarized the inhibition prediction of the most interactive [NiL2Cl2], then [FeL2Cl2] complexes as confirmed by the binding energy values (- 7.1 kacl/mol and - 6.4 kacl/mol, respectively). Another In silico results, with gram-positive bacteria (S. aureus), estimated similar results of the experimental finding, where [MnL2Cl2] (- 9.2 kcal/mol) is the more effective predicted antibacterial inhibitor. Fluorescence microscopy was used to examine the inhibition of bacterial biofilm, and the DPPH assay was used to measure antioxidant activity, followed by an understanding of the behavior of the current complexes toward free radicals' removal. The findings observed less aggregated bacterial strains covered with the studied complexes leading to less dense biofilm covering.}, }
@article {pmid39856522, year = {2025}, author = {Liu, A and Zhao, H and Wu, B and Zheng, S and Zuo, L and Wang, M}, title = {[Bacterial biofilm formation of peritoneal dialysis catheter in patients with peritonitis-associated catheter removal].}, journal = {Beijing da xue xue bao. Yi xue ban = Journal of Peking University. Health sciences}, volume = {57}, number = {1}, pages = {161-165}, pmid = {39856522}, issn = {1671-167X}, mesh = {Humans ; *Biofilms ; Female ; *Peritonitis/microbiology/etiology ; Male ; Middle Aged ; *Peritoneal Dialysis/adverse effects/instrumentation ; Retrospective Studies ; Catheters, Indwelling/microbiology/adverse effects ; Catheter-Related Infections/microbiology ; Device Removal ; Aged ; }, abstract = {OBJECTIVE: Peritoneal dialysis(PD)-associated peritonitis is a common and major complication of PD and the most common cause of technical failure of PD. The presence of bacterial biofilm may be an important factor leading to refractory or recurrence of peritonitis. To investigate the formation and characteristics of bacterial biofilms on PD catheters after peritonitis-associated catheter removal.<br><br>METHODS: The patients with maintenance PD who were regularly followed up in the Peking University People' s Hospital from June 2007 to January 2022 were retrospectively analyzed. The patients who withdrew from PD because of peritonitis and removed the PD catheter in our hospital and underwent the scanning electron microscope examination of the catheter were selected. The general information of the patients, the electron microscope results of the PD catheter and the bacterial culture results of the PD fluid were summarized.<br><br>RESULTS: (1) A total of 18 patients were included, 11 were female (accounting for 61.1%). The average age of the patients was (59.1&#xb1;11.5) years, and the average duration of dialysis was (80.1&#xb1;47.4) months. Primary kidney diseases were predominantly chronic glomerulonephritis (55.6%), followed by diabetic nephropathy (27.8%), and others (16.6%). The reasons for catheters removal in 18 patients were refractory peritonitis in 11 cases, recurrent peritonitis in 5 cases, and fungal peritonitis in 2 cases. (2) 16 of the 18 patients (88.9%) had catheter bacterial biofilm, and the bacterial biofilm forms were all cocci. Some were arranged in grape-like shapes, and their diameters ranged from about 500 nm to 1 000 nm. The bacterial culture results of peritoneal dialysis fluid showed that the three most common pathogens were Escherichia coli, methicillin-sensitive Staphylococcus aureus (MSSA), and Staphylococcus epidermidis. (3) Among the 18 patients enrolled, 13 patients (72.2%) had peritonitis in the past. The causative bacteria of peritonitis in 9 patients were cocci, including coagulase-negative Staphylococci (Staphylococcus suis, Staphylococcus surface, Staphylococcus xylosus, Staphylococcus warneri), Staphylococcus aureus, Streptococcus (Streptococcus salivarius and Aerococus viridans).<br><br>CONCLUSION: Bacterial biofilm formation on the inner surface of PD catheter is common in peritonitis-associated catheter removal patients. Not all PD catheters removed due to peritonitis have bacterial biofilms. Bacterial biofilms and peritonitis pathogens may not be consistent.}, }
@article {pmid39855517, year = {2025}, author = {Alhadrami, HA and Sayed, AM and Hassan, HM and Rateb, ME and Taha, MN}, title = {Optimized peptide inhibitor Aqs1C targets LasR to disrupt quorum sensing and biofilm formation in Pseudomonas aeruginosa: Insights from MD simulations and in vitro studies.}, journal = {International journal of biological macromolecules}, volume = {300}, number = {}, pages = {140119}, doi = {10.1016/j.ijbiomac.2025.140119}, pmid = {39855517}, issn = {1879-0003}, abstract = {Pseudomonas aeruginosa (PA) is a critical pathogen, and its antibiotic resistance is largely driven by the quorum-sensing regulator LasR. Herein, we report the design, synthesis, and characterization of Aqs1C, a mutated peptide derivative of Aqs1, optimized to inhibit LasR and its quorum-sensing pathway. By introducing a targeted mutation, Aqs1C exhibited enhanced stability and binding affinity for LasR protein compared to its predecessor, Aqs1B. Using molecular dynamics simulations (MDS), the Aqs1C-LasR complex demonstrated a marked increase in structural stability, reflected in reduced root mean square deviation (RMSD) values and lower binding free energy. Electrostatic complementarity analysis showed stronger and more favorable interactions between Aqs1C and LasR. Further, GaMD experiments were able to reproduce the binding state between Aqs1C and LasR, indicating the binding mechanism between them. These molecular insights correlated with functional in vitro assays. Aqs1C effectively inhibited quorum-sensing-associated virulence factors in PA, involving biofilm formation (77.6 % inhibition), pyocyanin production (75.7 % inhibition), protease secretion (61.1 % inhibition), and rhamnolipid production (74.1 % inhibition), at a 100 μg/mL concentration, in a comparable or superior pattern to azithromycin (AZM). Molecular modelling, MDS, and GaMD insights and in vitro assays established Aqs1C as a promising candidate for therapeutic development to mitigate PA infections through targeted quorum-sensing disruption.}, }
@article {pmid39854396, year = {2025}, author = {Sadanandan, B and Vijayalakshmi, V and Ashrit, P and Babu, UV and Sharath Kumar, LM and Sampath, V and Shetty, K and Joglekar, AP and Awaknavar, R}, title = {Correction: Aqueous spice extracts as alternative antimycotics to control highly drug resistant extensive biofilm forming clinical isolates of Candida albicans.}, journal = {PloS one}, volume = {20}, number = {1}, pages = {e0318383}, pmid = {39854396}, issn = {1932-6203}, abstract = {[This corrects the article DOI: 10.1371/journal.pone.0281035.].}, }
@article {pmid39854347, year = {2025}, author = {Guillín, Y and Ortiz, C and Hidalgo, W}, title = {Comparative metabolic study of planktonic and sessile cells in Salmonella Enteritidis ATCC 13076: Elucidating metabolic pathways driving biofilm formation.}, journal = {PloS one}, volume = {20}, number = {1}, pages = {e0317420}, pmid = {39854347}, issn = {1932-6203}, mesh = {*Biofilms/growth &amp; development ; *Salmonella enteritidis/metabolism ; *Metabolic Networks and Pathways ; *Plankton/metabolism ; Metabolomics ; Metabolome ; }, abstract = {Microorganisms tend to accumulate on surfaces, forming aggregates such as biofilms, which grant them resistance to various environmental stressors and antimicrobial agents. This ability has hindered the effective treatment of diseases caused by pathogenic microorganisms, including Salmonella, which is responsible for a significant number of deaths worldwide. This study aimed to compare the metabolic profiles of planktonic and sessile cells of Salmonella Enteritidis using a metabolomics approach. The metabolites extracted from the bacterial cells were analyzed by LC/MS approach. Raw data were analyzed using Thermo Xcalibur v 3.1 software. For data processing, XCMS was used for feature detection, retention time, correction and alignment. The data matrix was analyzed by uni- and multivariate statistical methods (PCA, PLS-DA, Heatmap) in MetaboAnalyst software v 6.0. A total of 121 metabolites were presumptively identified as differential metabolic characteristics between the two bacterial states, and they were associated with their corresponding metabolic pathways. Among the metabolites that exhibited positive modulation in planktonic cells were proline, phenylalanine, which act as precursors of essential metabolites and part of the stress adaptation mechanisms. In addition, putrescine and cadaverine, play crucial roles in growth, stress response, and cell stability In contrast, the most representative metabolites in sessile cells included lysine, adenosine, purines, pyrimidines, and citrate, mainly associated with maintaining cellular homeostasis, stress response and metabolic regulation. Finally, pathway enrichment analysis identified metabolic changes in 11 pathways, predominantly involving purine and pyrimidine metabolism, arginine and proline metabolism, and vitamin B6 metabolism. These findings facilitated the identification of potential metabolic pathways associated with biofilm formation in the sessile cells of Salmonella Enteritidis.}, }
@article {pmid39852568, year = {2025}, author = {Koji Uehara, E and Castro de Lima, G and Sardi, JCO and de Figueiredo, LC and Shibli, JA and Asbi, T and Haim, D and Augusto Rodrigues, J}, title = {Next-Generation Dental Materials: Exploring Bacterial Biofilm Formation on 3D-Printable Resin-Based Composites.}, journal = {Journal of functional biomaterials}, volume = {16}, number = {1}, pages = {}, pmid = {39852568}, issn = {2079-4983}, abstract = {This study evaluated the microbial growth profile of subgingival multispecies biofilm on 3D-printable resin-based composites (PRBCs). A 96-well cell plate cultivated a 39-species biofilm associated with periodontitis over 7 days. Cylindrical specimens with 12 mm high and 3 mm diameters were prepared by the PRBC group (Cosmos Temp-Yller; Prizma 3D Bio Crown; Prizma 3D Bio Prov) and an acrylic resin as control. Further, these specimens were immersed in the well plate to allow biofilm formation. After growing for 7 days, the metabolic biofilm activity was evaluated by colorimetric assay and the microbial profile by DNA-DNA hybridization. Kruskal-Wallis and Mann-Whitney tests evaluated each bacteria count and complex group. A greater biofilm formation was observed on PRBC groups than on acrylic resin. The microbiological profile of PRBC was associated with a less pathogenic biofilm, with an absence of a red complex. Acrylic resin showed low biofilm growth, but the biofilm profile was related to periodontal disease, characterized by red-complex bacteria. The selection of PRBC may contribute more effectively to maintaining periodontal health than acrylic resin.}, }
@article {pmid39852472, year = {2025}, author = {Hernández-Benítez, JA and Santos-Ocampo, BN and Rosas-Ramírez, DG and Bautista-Hernández, LA and Bautista-de Lucio, VM and Pérez, NO and Rodríguez-Tovar, AV}, title = {The Effect of Temperature over the Growth and Biofilm Formation of the Thermotolerant Aspergillus flavus.}, journal = {Journal of fungi (Basel, Switzerland)}, volume = {11}, number = {1}, pages = {}, pmid = {39852472}, issn = {2309-608X}, support = {SIP 20230236, SIP 20240616//Instituto Polit&#xe9;cnico Nacional/ ; }, abstract = {Aspergillus flavus is a medically relevant fungus, particularly in tropical regions. Although its aflatoxin production and thermotolerance are well documented, its biofilm-forming ability has received less attention, despite being a key factor in the virulence of A. flavus as an opportunistic pathogen, which can significantly impact therapeutic outcomes. To investigate the influence of temperature on the growth and biofilm formation of an A. flavus isolate, we compared it on solid media with the reference strain A. flavus ATCC 22546 and documented morphological changes during conidial germination. We examined biofilm formation in both strains across different temperatures and evaluated the susceptibility of this A. flavus isolate to antifungal agents in both planktonic and biofilm form. Our results showed that the temperature can promote conidiation on solid media. Radial growth was highest at 28 °C, while the conidial count and density were favored at higher temperatures. Moreover, we determined that 37 °C was the optimal temperature for conidial germination and biofilm formation. We described four distinct phases in A. flavus biofilm development-initiation (0-12 h), consolidation (12-24 h), maturation (24-48 h), and dispersion (48-72 h)-with the notable presence of conidial heads at 42 °C. Carbohydrates and proteins constitute the primary components of the extracellular matrix. We observed an abundance of lipid droplets within the hyphae of the MMe18 strain biofilm. The mature biofilms demonstrated reduced susceptibility to amphotericin B and itraconazole, requiring higher inhibitory concentrations for both antifungals compared with their planktonic counterparts.}, }
@article {pmid39851994, year = {2025}, author = {Sadanandan, B and Vijayalakshmi, V and Shetty, K and Rathish, A and Shivkumar, H and Gundreddy, M and Narendra, NKK and Devaiah, NM}, title = {In Situ Aqueous Spice Extract-Based Antifungal Lock Strategy for Salvage of Foley's Catheter Biofouled with Candida albicans Biofilm Gel.}, journal = {Gels (Basel, Switzerland)}, volume = {11}, number = {1}, pages = {}, pmid = {39851994}, issn = {2310-2861}, support = {7.1.01/SPP/10//THE KARNATAKA STATE COUNCIL FOR SCIENCE AND TECHNOLOGY (KSCST)/ ; }, abstract = {Candida forms a gel-like biofilm in the Foley's catheter (FC) causing tenacious biofouling and severe urinary tract infections (UTIs). For the first time, a spice extract-based antifungal lock therapy (ALT) has been developed to inhibit the Candida albicans gel matrix in FC. Aqueous extracts of garlic, clove, and Indian gooseberry were used as ALT lock solutions and tested against biofilm-forming multidrug-resistant clinical isolates of C. albicans. Reduction in the gel matrices formation in the catheter was confirmed by Point inoculation, MTT assay, CFU, and SEM analysis at 12 and 24 h of incubation. Garlic was effective in controlling both C. albicans M207 and C. albicans S470; however, clove and gooseberry effectively controlled the latter. As evidenced by CFU assay, there were 82.85% and 99.68% reductions in the growth of C. albicans M207 and S470, respectively, at 24 h of incubation. SEM revealed a switch from the biofilm to the yeast mode and a drastic reduction in cell numbers, with mostly clumped or lysed cells. The study will provide an impetus to the development of novel spice extract-based ALT, reducing the selection pressure on the pathogen and lowering antimicrobial resistance. Further research in this area has the potential to leverage clinical applications.}, }
@article {pmid39850422, year = {2025}, author = {Jomehzadeh, N and Emrani, SS}, title = {Assessment of biofilm formation, antibiotic resistance patterns, and the prevalence of adhesion-related genes in clinical Staphylococcus aureus isolates.}, journal = {Heliyon}, volume = {11}, number = {1}, pages = {e41537}, pmid = {39850422}, issn = {2405-8440}, abstract = {BACKGROUND: This study aimed to evaluate the biofilm formation abilities of clinical Staphylococcus aureus strains, assess their antibiotic susceptibility patterns, and identify the prevalence of adhesion-associated genes.<br><br>METHODOLOGY: In this study, a total of 60&#xa0;S. aureus strains were collected from urine, pus, wounds, blood, body fluid, and sputum in health centers affiliated with Abadan University of Medical Sciences, Iran. Strains were identified via microbiological methods and polymerase chain reaction (PCR) to target the nuc gene. Antibiotic susceptibility testing (AST) was conducted via the disc diffusion method. Methicillin-resistant S. aureus (MRSA) strains were identified by cefoxitin disc diffusion and PCR targeting the mecA gene. Biofilm formation was assessed via a microtiter plate assay, and the prevalence of adhesion-encoding genes was evaluated via PCR. The data were analyzed in Excel and SPSS via statistical methods, with P-values <0.05 considered significant.<br><br>RESULTS: Using AST, daptomycin and linezolid were the most effective antibiotics (100&#xa0;% susceptibility rate). According to the results of the cefoxitin disc test, 48.3&#xa0;% (n&#xa0;=&#xa0;29/60) of the strains were MRSA. All the MRSA strains harbored the mecA gene. In total, 32&#xa0;% of the strains were biofilm producers. Moreover, 56.2&#xa0;%, 28.1&#xa0;%, and 15.6&#xa0;% of the strains produced weak, moderate, and strong biofilms, respectively. There were no significant differences between the MRSA and MSSA strains in terms of the association of biofilm formation with antibiotic resistance except for erythromycin (P-value&#xa0;=&#xa0;0.0087), gentamicin (P-value&#xa0;=&#xa0;0.0009), and penicillin (P-value&#xa0;=&#xa0;0.0009). The most prevalent biofilm-encoding genes were icaA (76.7&#xa0;%), followed by icaD (70&#xa0;%), clfA (65.0&#xa0;%), and fnbA (53.3&#xa0;%).<br><br>CONCLUSION: This study identified MRSA strains with biofilm-forming abilities that possess adhesion-associated genes. The most prevalent biofilm-encoding gene was icaA. To prevent further spread of these strains, regional preventive measures are needed.}, }
@article {pmid39850403, year = {2025}, author = {Stannius, RO and Fusco, S and Cowled, MS and Kovács, &#xc1;T}, title = {Surfactin accelerates Bacillus subtilis pellicle biofilm development.}, journal = {Biofilm}, volume = {9}, number = {}, pages = {100249}, pmid = {39850403}, issn = {2590-2075}, abstract = {Surfactin is a biosurfactant produced by many B. subtilis strains with a wide variety of functions from lowering surface tension to allowing motility of bacterial swarms, acting as a signaling molecule, and even exhibiting antimicrobial activities. However, the impact of surfactin during biofilm formation has been debated with variable findings between studies depending on the experimental conditions. B. subtilis is known to form biofilms at the solid-air, the solid-medium, and the liquid-air interfaces, the latter of which is known as a pellicle biofilm. Pellicle formation is a complex process requiring coordinated movement to the liquid-air interface and subsequent cooperative production of biofilm matrix components to allow robust pellicle biofilm formation. This makes pellicle formation a promising model system for assaying factors in biofilm formation and regulation. Here, we assayed the influence of surfactin and additional metabolites on the timing of pellicle biofilm formation. Using time-lapse imaging, we assayed pellicle formation timing in 12 B. subtilis isolates and found that one, MB9_B4, was significantly delayed in pellicle formation by approximately 10 h. MB9_B4 was previously noted to lack robust surfactin production. Indeed, deletion of surfactin synthesis in the other isolates delayed pellicle formation. Further, pellicle delay was rescued by addition of exogeneous surfactin. Testing reporters of biofilm-related gene expression revealed that induction of pellicle formation was caused by a combination of increased gene expression of one of the biofilm components and promotion of growth.}, }
@article {pmid39848304, year = {2025}, author = {Sun, H and Sun, S and Wang, H and Cheng, K and Zhou, Y and Wang, X and Gao, S and Mo, J and Li, S and Lin, H and Wang, P}, title = {Phenylboronic acid-modified carbon dot-proteinase K nanohybrids for enhanced photodynamic therapy against bacterial biofilm infections.}, journal = {Acta biomaterialia}, volume = {}, number = {}, pages = {}, doi = {10.1016/j.actbio.2025.01.030}, pmid = {39848304}, issn = {1878-7568}, abstract = {Nanohybrids combining phenylboronic acid-modified carbon dots (PCDs) and proteinase K have been engineered for addressing the formidable challenges of antimicrobial photodynamic therapy (aPDT) against bacterial biofilm infections, overcoming biofilm barrier obstruction, the limited diffusion of reactive oxygen species (ROS), and the inadequate ROS generation of traditional photosensitizers. PCDs are formulated for superior water solubility and robust singlet oxygen ([1]O2) production, mitigating issues related to dispersion and aggregation-induced quenching typical of conventional photosensitizers. The conjugation of phenylboronic acid to CDs not only enhanced [1]O2 generation through increased electron-hole separation but also imparted strong bacterial binding capabilities to the PCDs, enabling broad-spectrum sterilization by maximizing the ROS-mediated bacterial destruction. Proteinase K, serving as a structural "glue", actively breaks down biofilms and facilitates the deep penetration of functional PCDs, aiding effective treatment of biofilm infections. In vivo studies confirm that PCDs-proteinase K nanohybrids dramatically accelerate healing in biofilm-infected wounds by synergizing enhanced photosensitization, potent bacterial adherence, and efficient biofilm elimination and penetration. This approach highlights a straightforward strategy to significantly advance aPDT, promoting the clinical adoption of non-antibiotic methods for combating bacterial biofilm infections. STATEMENT OF SIGNIFICANCE: 1) Phenylboronic acid-modified carbon dots (PCDs) were designed for enhanced water solubility and efficient singlet oxygen generation through surface modulation, also suggesting that surface modification can improve the inherent photosensitizing activity of CDs by promoting electron-hole separation; 2) The conjugation of phenylboronic acid endowed PCDs with strong bacterial binding capabilities, enabling highly efficient and broad-spectrum sterilization by maximizing reactive oxygen species-mediated bacterial destruction; 3) Incorporation of proteinase K (PK) leveraged its specific extracellular polymeric substance degrading capability, along with the stimuli-responsive release of PCDs from the PCDs-PK nanohybrids, facilitating biofilm breakdown and enabling deeper penetration of PCDs, thereby improving the treatment of biofilm infections.}, }
@article {pmid39846084, year = {2025}, author = {Santos, TM and Lopes, MET and de Alencar, ER and Silva, MVA and Machado, SG}, title = {Ozonized water as a promising strategy to remove biofilm formed by Pseudomonas spp. on polyethylene and polystyrene surfaces.}, journal = {Biofouling}, volume = {41}, number = {2}, pages = {144-156}, doi = {10.1080/08927014.2024.2444387}, pmid = {39846084}, issn = {1029-2454}, mesh = {*Biofilms/drug effects ; *Polystyrenes/chemistry ; *Polyethylene/chemistry ; *Pseudomonas/physiology ; *Ozone/pharmacology/chemistry ; Water/chemistry ; Disinfection/methods ; Surface Properties ; }, abstract = {The dairy industry faces challenges in controlling spoilage microorganisms, particularly Pseudomonas, known to form resilient biofilms. Conventional disinfection methods have limitations, prompting the exploration of eco-friendly alternatives like ozone. This study focused on Pseudomonas biofilms on polystyrene and polyethylene surfaces, evaluating ozone efficacy when incorporated into different water sources and applied under static and dynamic conditions. Biofilm formation and removal were assessed with conventional microbiological and microscopic techniques. Despite variations in physicochemical properties, ozonized water from different sources showed similar effectiveness in removing Pseudomonas biofilms. Dynamic ozone application was more efficient, achieving a 2.35 log CFU/coupon reduction on polyethylene surfaces, compared to a 1.05 log CFU/coupon reduction under static conditions. These findings highlight the potential of ozonized water for removing Pseudomonas biofilms, especially under dynamic application. This eco-friendly approach could serve as an effective strategy to mitigate biofilm-related challenges in the dairy industry.}, }
@article {pmid39845530, year = {2025}, author = {Fernández, L and Duarte, AC and Jurado, A and Bueres, L and Rodríguez, A and García, P}, title = {Multipronged impact of environmental temperature on Staphylococcus aureus infection by phage Kayvirus rodi: Implications for biofilm control.}, journal = {Biofilm}, volume = {9}, number = {}, pages = {100248}, pmid = {39845530}, issn = {2590-2075}, abstract = {Environmental cues sometimes have a direct impact on phage particle stability, as well as bacterial physiology and metabolism, having a profound effect on phage infection outcome. Here, we explore the impact of temperature on the interplay between phage Kayvirus rodi (phiIPLA-RODI) and its host, Staphylococcus aureus. Our results show that phiIPLA-RODI is a more effective predator at room (25 °C) compared to body temperature (37 °C) against planktonic cultures of several strains with varying degrees of phage susceptibility. This result differs from most known examples of temperature-dependent phage infection, in which optimum infection is correlated with the host growth rate. Further characterization of this phenomenon was carried out with strains IPLA15 and IPLA16, whose respective MICs were 7 log units and a 1-log unit higher at 37 °C than at 25 °C. Our results demonstrated that the phage also had a greater impact at room temperature during biofilm development and for the treatment of preformed biofilms. There was no difference in phage adsorption between the two temperatures for strain IPLA16. Conversely, adsorption of phiIPLA-RODI to IPLA15 was reduced at 37 °C compared to 25 °C. Moreover, confocal microscopy analysis indicated that the biofilm matrix of both strains has a greater content of PIA/PNAG at 37 °C than at 25 °C. Regarding infection parameters, we observed longer duration of the lytic cycle at 25 °C for both strains, and infection of IPLA15 by phiIPLA-RODI resulted in a smaller burst size at 37 °C than at 25 °C. Finally, we also found that the rate of phage resistant mutant selection was higher at 37 °C for both strains. Altogether, this information highlights the impact that bacterial responses to environmental factors have on phage-host interactions. Moreover, phage phiIPLA-RODI appears to be a highly effective candidate for biofilm disinfection at room temperature, while its efficacy in biofilm-related infections will require combination with other antimicrobials.}, }
@article {pmid39844868, year = {2024}, author = {Ray, RR}, title = {Biofilm architecture and dynamics of the oral ecosystem.}, journal = {Biotechnologia}, volume = {105}, number = {4}, pages = {395-402}, pmid = {39844868}, issn = {2353-9461}, abstract = {The oral cavity, being a nutritionally enriched environment, has been proven to be an ideal habitat for biofilm development. Various microenvironments, including dental enamel, supra- and subgingival surfaces, salivary fluid, and the dorsal surface of the tongue, harbor diverse microbes. These biofilms typically consist of four major layers. Depending on the food, age, clinical state, and lifestyle of the patient, the microbial growth dynamics in oral biofilm varies significantly. The presence of pathogenic bacteria that disrupt the normal floral composition of the oral cavity can lead to plaque biofilm formation, which is a precursor to various diseases. Noteworthy pathogenic bacteria, such as Porphyromonas gingivalis, Fusobacterium nucleatum, and Streptococcus mutans, often initiate biofilm formation. Undiagnosed and untreated oral biofilm can lead to severe diseases like periodontitis and eventual tooth loss. Therefore, studying the architecture and dynamics of oral biofilms is essential and can be achieved through image analysis and modern technologies, such as AI-enabled technologies and surface topography-adaptive robotic superstructures.}, }
@article {pmid39842734, year = {2025}, author = {Jhandai, P and Mittal, D and Gupta, R and Kumar, M}, title = {An insight into newly emerging avian pathogenic E. coli serogroups, biofilm formation, ESBLs and integron detection and in vivo pathogenicity in chicken.}, journal = {Microbial pathogenesis}, volume = {200}, number = {}, pages = {107309}, doi = {10.1016/j.micpath.2025.107309}, pmid = {39842734}, issn = {1096-1208}, abstract = {Bacterial diseases alone or in combination with other pathogens lead to significant economic losses in poultry globally including India. One of these diseases is avian colibacillosis which is caused by avian pathogenic Escherichia coli (APEC). The present study sought to isolate and characterize using in vivo and in vitro assays E. coli recovered from poultry diagnosed with colibacillosis. A total of 55 E. coli isolates were recovered from tissues of 55 broiler flocks affected with colibacillosis by using standard microbiological techniques, Vitek 2 Compact system and polymerase chain reaction. Out of 55 E. coli isolates, 50 (90.9 %) were characterized as APEC by multiplex PCR using a set of five virulence genes. On serotyping, 16 (32 %) APEC isolates were serogrouped as O26 followed by O98 (28 %), O120 (14 %), O11 (12 %), O135 (8 %) and O17 (4 %). The antimicrobial susceptibility testing of E. coli isolates revealed high antibiotic resistance against imipenem, tetracycline, ciprofloxacin and levofloxacin (96 % each). Interestingly all the 50 suspect APEC isolates were found to be multiple drug resistant (MDR) and the antimicrobial profiling indicated that these isolates could be classified into 38 resistotypes. Moreover, 10 (20 %) isolates were ESBL producers as per phenotypic characterization using combined disk diffusion test. On genotypic characterization of ESBLs, 31 (62 %) isolates were found positive for the blaTEM gene, whereas, 34 (68 %) isolates carried intI1 gene. On assessment for biofilm formation at 72 h incubation, thirteen (26 %) isolates were found to be strong biofilm producers, whereas nine (18 %) and twenty-eight (56 %) isolates were moderate and weak biofilm producers, respectively. Later, the LD50 of one MDR and strong biofilm producing isolate (APEC-P02) was calculated by in vivo oral challenge study in day old broiler chicks. The findings of this study demonstrated that LD50 of APEC-P02 isolate was 1.12 × 10[8] CFU/ml. The unexpectedly high prevalence of O11, O126, O98, O120 and O135 isolates suggest that there may be emergent serogroups causing colibacillosis in India. The current oral challenge study seems to be the first of its kind in India to estimate the LD50 of a multidrug resistant biofilm producer APEC isolate in day-old chicks.}, }
@article {pmid39842355, year = {2025}, author = {Li, N and Li, X and Zhao, L and Lu, ZD and Liu, YW and Wang, N}, title = {Slow sand filters with variable filtration rates for rainwater purification: Microecological differences between biofilm and water phases.}, journal = {Journal of environmental management}, volume = {375}, number = {}, pages = {124210}, doi = {10.1016/j.jenvman.2025.124210}, pmid = {39842355}, issn = {1095-8630}, mesh = {*Biofilms ; *Filtration/methods ; *Rain ; Sand ; Water Purification/methods ; }, abstract = {Slow sand filters (SSFs) have been increasingly applied to rainwater purification in recent years, but the response of SSFs to fluctuating rainfall, as well as the biofilm- and water-phase microecology in SSFs are still poorly understood. This study systematically evaluated the rainwater purification performance of SSFs and compared the bacterial community structure, assembly processes and molecular ecological interactions between the biofilm and water phases. The activated carbon and activated alumina filters exhibited the best performance for NH4[+]-N (18.82%∼64.00%) and TP (>90%) removal, respectively. As the filtration rate increased from 0.1 m/h to 0.3 m/h, the rainwater purification efficiencies of the three SSFs deteriorated significantly, with the enrichment of Tolumonas, Desulfovibrio and Sulfurospirillum, and reduction in Klebsiella and Enterobacter. The community diversity of biofilm phase was significantly higher than that of water phase, and filtration rate was identified as a key factor in shaping the bacterial community in both phases. The interactions of filtration rate and water quality displayed the best and significant (p < 0.01) explanation for microbiome shift, with the higher values in biofilm phase (34.70%) than in water phase (24.02%). Bacterial community assembly in SSFs was determined by stochastic ecological processes, which played a more important role in water-phase communities, with 86.34% following predictions using a neutral community model. The molecular ecological network of biofilm phase exhibited more complexity, lower modularity and more cooperative relationships than that of water phase. Disadvantaged OTUs occupied core and notable positions in the network, with the highest degree and clustering coefficient. Different keystone species were identified in biofilm- (Runella, Aquabacterium, etc) and water-network (Terrimonas) respectively, despite they processed low relative abundances (<0.1%). These results enhance the understanding of microecology in SSFs, and shed new lights on the improvement and promotion of rainwater biological treatment technology.}, }
@article {pmid39842203, year = {2025}, author = {Liu, M and Bai, Y and Feng, M and Wang, X and Ni, L and Cai, L and Cao, Y}, title = {The synergistic antibacterial effects of allicin nanoemulsion and ε-polylysine against Escherichia coli in both planktonic and biofilm forms.}, journal = {Food chemistry}, volume = {472}, number = {}, pages = {142949}, doi = {10.1016/j.foodchem.2025.142949}, pmid = {39842203}, issn = {1873-7072}, abstract = {The synergistic effects of allicin nanoemulsion (AcN) and ε-polylysine (ε-PL) against Escherichia coli were investigated in this study. The combination of AcN and ε-PL synergistically inhibited the planktonic growth of E. coli, with a low fractional inhibitory concentration index of 0.252. AcN/ε-PL treatment remarkably promoted the agent-cell contacts compared to AcN or ε-PL treatment, as evidenced by the larger cellular size and lower absolute zeta potential value. Analysis of membrane potential, intracellular ATP and superoxide dismutase activity revealed that the co-treatment induced membrane depolarization and intracellular metabolic disorders. Laser scanning confocal microscope, flow cytometer, and scanning electron microscope revealed that the membrane integrity and cell structure were severely degraded. Further, biofilm formation, cluster motility, and mature biofilm of E. coli were disrupted substantially by AcN/ε-PL. Finally, the application of AcN/ε-PL in raw beef preservation verified the synergy. Therefore, AcN/ε-PL can be used as a potential bacteriostatic agent in food preservation.}, }
@article {pmid39841058, year = {2025}, author = {Gao, Q and Yang, H and Sheiber, J and Bartolomeu Halicki, PC and Liu, K and Blanco, D and Milhous, S and Jin, S and Rohde, KH and Fleeman, RM and Huigens Iii, RW}, title = {Identification of 6,8-ditrifluoromethyl halogenated phenazine as a potent bacterial biofilm-eradicating agent.}, journal = {Organic &amp; biomolecular chemistry}, volume = {}, number = {}, pages = {}, pmid = {39841058}, issn = {1477-0539}, support = {R00 AI163295/AI/NIAID NIH HHS/United States ; R35 GM153272/GM/NIGMS NIH HHS/United States ; S10 OD021758/OD/NIH HHS/United States ; T32 GM136583/GM/NIGMS NIH HHS/United States ; }, abstract = {Bacterial biofilms are surface-attached communities consisting of non-replicating persister cells encased within an extracellular matrix of biomolecules. Unlike bacteria that have acquired resistance to antibiotics, persister cells enable biofilms to demonstrate innate tolerance toward all classes of conventional antibiotic therapies. It is estimated that 50-80% of bacterial infections are biofilm associated, which is considered the underlying cause of chronic and recurring infections. Herein, we report a modular three-step synthetic route to new halogenated phenazine (HP) analogues from diverse aniline and nitroarene building blocks. The HPs were evaluated for antibacterial and biofilm-killing properties against a panel of lab strains and multidrug-resistant clinical isolates. Several HPs demonstrated potent antibacterial (MIC ≤ 0.39 μM) and biofilm-eradicating activities (MBEC < 10 μM) with 6,8-ditrifluoromethyl-HP 15 demonstrated remarkable biofilm-killing potencies (MBEC = 0.15-1.17 μM) against Gram-positive pathogens, including methicillin-resistant Staphylococcus aureus clinical isolates. Confocal microscopy showed HP 15 induced significant losses in the polysaccharide matrix in MRSA biofilms. In addition, HP 15 showed increased antibacterial activities against dormant Mycobacterium tuberculosis (Mtb, MIC = 1.35 μM) when compared to replicating Mtb (MIC = 3.69 μM). Overall, this new modular route has enabled rapid access to an interesting series of potent halogenated phenazine analogues to explore their unique antibacterial and biofilm-killing properties.}, }
@article {pmid39840972, year = {2025}, author = {Zavan, L and Hor, L and Johnston, EL and Paxman, J and Heras, B and Kaparakis-Liaskos, M}, title = {Antigen 43 associated with Escherichia coli membrane vesicles contributes to bacterial cell association and biofilm formation.}, journal = {Microbiology spectrum}, volume = {}, number = {}, pages = {e0189024}, doi = {10.1128/spectrum.01890-24}, pmid = {39840972}, issn = {2165-0497}, abstract = {Bacterial membrane vesicles (MVs) are produced by all bacteria and contribute to numerous bacterial functions due to their ability to package and transfer bacterial cargo. In doing so, MVs have been shown to facilitate horizontal gene transfer, mediate antimicrobial activity, and promote biofilm formation. Uropathogenic Escherichia coli is a pathogenic Gram-negative organism that persists in the urinary tract of its host due to its ability to form persistent, antibiotic-resistant biofilms. The formation of these biofilms is dependent upon proteins such as Antigen 43 (Ag43), which belongs to the widespread Autotransporter group of bacterial surface proteins. In E. coli, the autotransporter Ag43 has been shown to contribute to bacterial cell aggregation and biofilm formation via self-association of Ag43 between neighboring Ag43-expressing bacteria. As MVs package bacterial proteins, we investigated whether MVs produced by E. coli contained Ag43, and the ability of Ag43-expressing MVs to facilitate cell aggregation and biofilm formation. We showed that Ag43 expressing E. coli produced MVs that contained Ag43 on their surface and had an enhanced ability to bind to E. coli bacteria. Furthermore, we demonstrated that the addition of Ag43-containing MVs to Ag43-expressing E. coli significantly enhanced biofilm formation. These findings reveal the contribution of MVs harboring autotransporters in promoting bacterial aggregation and enhancing biofilm formation, highlighting the impact of MVs and their specific composition to bacterial adaptation and pathogenesis.IMPORTANCEAutotransporter proteins are the largest family of outer membrane and secreted proteins in Gram-negative bacteria which contribute to pathogenesis by promoting aggregation, biofilm formation, persistence, and cytotoxicity. Although the roles of bacterial autotransporters are well known, the ability of bacterial membrane vesicles (MVs) naturally released from the surface of bacteria to contain autotransporters and their role in promoting virulence remains less investigated. Our findings reveal that MVs produced by E. coli contain the autotransporter protein Ag43. Furthermore, we show that Ag43-containing MVs function to enhance bacterial cell interactions and biofilm formation. By demonstrating the ability of MVs to carry functional autotransporter adhesins, this work highlights the importance of MVs in disseminating autotransporters beyond the bacterial cell membrane to ultimately promote cellular interactions and enhance biofilm development. Overall, these findings have significant implications in furthering our understanding of the numerous ways in which MVs can facilitate bacterial persistence and pathogenesis.}, }
@article {pmid39838865, year = {2025}, author = {Kumar, VB and Lahav, M and Gazit, E}, title = {Correction: Preventing biofilm formation and eradicating pathogenic bacteria by Zn doped histidine derived carbon quantum dots.}, journal = {Journal of materials chemistry. B}, volume = {13}, number = {6}, pages = {2210}, doi = {10.1039/d5tb90012c}, pmid = {39838865}, issn = {2050-7518}, abstract = {Correction for 'Preventing biofilm formation and eradicating pathogenic bacteria by Zn doped histidine derived carbon quantum dots' by Vijay Bhooshan Kumar et al., J. Mater. Chem. B, 2024, 12, 2855-2868, https://doi.org/10.1039/D3TB02488A.}, }
@article {pmid39837152, year = {2025}, author = {Panebianco, F and Alvarez-Ordóñez, A and Oliveira, M and Ferreira, S and Lovisolo, S and Vono, C and Cannizzo, FT and Chiesa, F and Civera, T and Di Ciccio, P}, title = {Effect of neutral electrolyzed water on biofilm formed by meat-related Listeria monocytogenes: Intraspecies variability and influence of the growth surface material.}, journal = {International journal of food microbiology}, volume = {431}, number = {}, pages = {111064}, doi = {10.1016/j.ijfoodmicro.2025.111064}, pmid = {39837152}, issn = {1879-3460}, abstract = {Listeria monocytogenes raises major challenges for the food industry. Due to its capacity to form biofilms, this pathogen can persist in processing environments and contaminate the final products. Neutral electrolyzed water (NEW) may offer a promising and eco-friendly method for controlling L. monocytogenes biofilms, though current in vitro studies on its antibiofilm activity are limited and often focused on reference strains. In this study, we assessed the effect of NEW on biofilms formed by meat-related and reference L. monocytogenes strains on polystyrene and stainless steel. Forty wild-type strains isolated from meat products and processing environments were firstly screened for their biofilm-forming abilities and classified as weak (30 %; 12/40), moderate (55 %; 22/40), and strong (15 %; 6/40) biofilm producers. Twenty-two wild-type and two reference strains were selected for the eradication assays, performed by treating the biofilms with NEW for 9 minutes of total contact time. In silico functional enrichment analysis and the visualization of biofilms by scanning electron microscopy (SEM) were also performed. The NEW treatment resulted in a greater average reduction of viable cells in biofilms formed on polystyrene (4.3 ± 1.0 log10 CFU/cm[2]) compared to stainless steel (2.9 ± 2.0 log10 CFU/cm[2]), and a remarkable intraspecies variability was observed. SEM images revealed higher structural damage on biofilms formed on polystyrene. Functional enrichment analysis suggested that clustered regularly interspaced short palindromic repeats (CRISPR)-associated elements could be involved in resistance to the treatments. NEW could be a promising additional tool to mitigate L. monocytogenes biofilms in meat processing environments, although its effect varied with surface material and strain-specific characteristics.}, }
@article {pmid39836537, year = {2025}, author = {Feng, H and Liang, S and Li, R and Wang, H and Cai, R}, title = {Jannaschia maritima sp. nov., a novel marine bacterium isolated from the biofilm of concrete breakwater structures.}, journal = {International journal of systematic and evolutionary microbiology}, volume = {75}, number = {1}, pages = {}, doi = {10.1099/ijsem.0.006645}, pmid = {39836537}, issn = {1466-5034}, mesh = {*RNA, Ribosomal, 16S/genetics ; *Base Composition ; *Phylogeny ; *Fatty Acids/chemistry ; *DNA, Bacterial/genetics ; *Biofilms ; China ; *Bacterial Typing Techniques ; *Sequence Analysis, DNA ; *Seawater/microbiology ; *Ubiquinone ; Phospholipids/analysis ; Genome, Bacterial ; Nucleic Acid Hybridization ; }, abstract = {Marine biofilms were newly revealed as a bank of hidden microbial diversity and functional potential. In this study, a Gram-stain-negative, aerobic, oval and non-motile bacterium, designated LMIT008[T], was isolated from the biofilm of concrete breakwater structures located in the coastal area of Shantou, PR China. Strain LMIT008[T] was found to grow at salinities of 1-7% NaCl, at pH 5-8 and at temperatures 10-40 °C. Phylogenetic analysis based on 16S rRNA gene sequence indicated that strain LMIT008[T] belonged to the genus Jannaschia and was closely related to the type strains Jannaschia aquimarina KCTC23555[T] (96.03%) and Jannaschia marina SHC-163[T] (95.31%). The draft genome size of the strain LMIT008[T] was 3.67 Mbp, and the genomic DNA G+C content was 69.83 mol%. The average nucleotide identity value between strain LMIT008[T] and the closely related type strain J. aquimarina KCTC23555[T] was 74.82%. The predominant cellular fatty acids were identified as summed feature 8 (C18 : 1 ω7c/C18 : 1 ω6c) and C18 : 0, and the major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine. Ubiquinone-10 (Q-10) is the sole respiratory quinone. Further, genomic analysis of strain LMIT008[T] showed that the strain harbours abundant genes associated with biofilm formation and environmental adaption, explaining the potential strategies for living on concrete breakwater structures. Based on the morphological, phylogenetic, chemotaxonomic and phenotypic characterization, the strain LMIT008[T] was considered to represent a novel species in the genus of Jannaschia, for which the name Jannaschia maritima sp. nov. was proposed, with LMIT008[T] (=MCCC 1K08854[T]=KCTC 8321[T]) as the type strain.}, }
@article {pmid39836323, year = {2025}, author = {Daungsupawong, H and Wiwanitkit, V}, title = {Regarding "Quantitative analysis of Streptococcus mutans, Bifidobacterium, and Scardovia wiggsiae in occlusal biofilm and their association with Visible Occlusal Plaque Index (VOPI) and International Caries Detection and Assessment System (ICDAS)".}, journal = {European archives of paediatric dentistry : official journal of the European Academy of Paediatric Dentistry}, volume = {}, number = {}, pages = {}, doi = {10.1007/s40368-025-01004-x}, pmid = {39836323}, issn = {1996-9805}, }
@article {pmid39832775, year = {2025}, author = {Zellner, AA and Wirtz, DC and Schildberg, FA}, title = {In Vitro Efficacy of Phage Therapy Against Common Biofilm-forming Pathogens in Orthopedics and Trauma Surgery.}, journal = {Zeitschrift fur Orthopadie und Unfallchirurgie}, volume = {}, number = {}, pages = {}, doi = {10.1055/a-2436-7394}, pmid = {39832775}, issn = {1864-6743}, abstract = {Formation of biofilms by bacteria is a major challenge in a clinical setting. The importance of these biofilms increases in specialties where foreign bodies and prosthetic material are used. Orthopaedics is such a speciality and phage therapy could offer additional therapeutic options when dealing with biofilm infections.We conducted a systematic literature review using the PubMed database. We searched for phage activity against biofilms of the most common pathogens found in orthopaedics.The results of the systematic review were broken down into different categories and discussed accordingly. We concentrated on the time the biofilms were allowed to mature, and the surface they were grown on. In addition, we checked the efficacy of bacteriophages compared to antibiotics and when applied simultaneously with antibiotics. We also investigated the source of the phages, how they were tested for sensibility against the biofilms, as well the conditions (pH, temperature) under which they remained active and stable.The data suggests that the in vitro efficacy of phages does not change under a wide spectrum of temperature and pH. To further explore the use of bacteriophages in orthopaedics, we need further studies that test biofilms which matured for several weeks on surfaces that are common in arthroplasty and traumatology.}, }
@article {pmid39832592, year = {2025}, author = {Fan, Y and Zheng, J and Tan, Y and Huang, L and Yan, Q and Wang, J and Weng, Q}, title = {Selection of biofilm-inhibiting ssDNA aptamers against antibiotic-resistant Edwardsiella tarda by inhibition-SELEX and interaction with their binding proteins.}, journal = {International journal of biological macromolecules}, volume = {299}, number = {}, pages = {140041}, doi = {10.1016/j.ijbiomac.2025.140041}, pmid = {39832592}, issn = {1879-0003}, abstract = {Biofilms can increase bacterial resistance to antibiotic therapies. Edwardsiella tarda with biofilm is highly resistant to antibacterial treatment, especially for the antibiotic-resistant strain. In this study, we obtained biofilm-inhibiting aptamers against antibiotic-resistant E. tarda via a novel systematic evolution of ligands by exponential enrichment (SELEX) technique, called inhibition-SELEX. After four rounds of screening and validation, we identified aptamers IB1, IB2, and IB3, which demonstrated biofilm-inhibition and biofilm-degradation rates of 69 %, 75 %, and 62 % and 51 %, 63 %, and 45 % at 2 μmol/L, respectively, against antibiotic-resistant E. tarda. Magnetic separation, SDS-PAGE, and mass spectrometry analyses revealed that all three aptamers could bind to glyceraldehyde-3-phosphate dehydrogenase (GAPDH), while IB2 could also bind to formate C-acetyltransferase (FA). Through molecular docking and molecular dynamics simulations, it was found that the four complexes primarily interact through hydrogen bonding. Among them, IB1-GAPDH exhibited the strongest stability, followed by IB2-FA, then IB2-GAPDH, and IB3-GAPDH was the least stable. Our results suggest that IB1, IB2, and IB3 may inhibit and degrade E. tarda biofilm by interfering with the synthesis, secretion, and transportation of its extracellular polysaccharides and proteins by interacting with GAPDH and FA.}, }
@article {pmid39832544, year = {2025}, author = {Zhu, Y and Wang, X and Liang, L and Yan, K and Huang, Y and Wang, Y}, title = {Community assembly and succession of the functional membrane biofilm in the anammox dynamic membrane bioreactor: Deterministic assembly of anammox bacteria.}, journal = {Environmental research}, volume = {269}, number = {}, pages = {120893}, doi = {10.1016/j.envres.2025.120893}, pmid = {39832544}, issn = {1096-0953}, abstract = {The anammox dynamic membrane bioreactor (DMBR) exhibits potential for efficient nitrogen removal via anammox processes. The functional membrane biofilm in the anammox DMBR significantly enhances nitrogen removal, ensuring robust operation. Nevertheless, ecological mechanisms underpinning the nitrogen removal function of the membrane biofilm remain unclear. We investigated the community succession and assembly of the membrane biofilm communities in two anammox DMBRs utilizing distinct inoculated anammox sludges. Anammox bacteria displayed niche differentiation in both DMBRs. Anammox bacteria Candidatus Kuenenia was selectively enriched to 8.5% abundance in the membrane biofilm communities, contributing to 5.2-7.2% of the nitrogen removal load. Membrane biofilm communities were primarily assembled through deterministic processes. Specifically, the selective enrichment of Candidatus Kuenenia on the membrane biofilms was primarily governed by homogenous selection process, explaining 9.67-9.82% of the variance. The deterministic assemblies of anammox bacteria were mainly influenced by the high substrate affinity of Candidatus Kuenenia and the limited availability of substrates (NH4[+] and NO2[-]) in the membrane biofilms. Furthermore, the relatively weak permeate drag force during the DMBR filtration facilitated the preferential colonization of microbes from the anammox sludge to the membrane biofilm, resulting in the deterministic formation of the membrane biofilm communities with nitrogen removal function. Our findings offer insights into the ecological mechanisms driving the deterministic assembly of the functional membrane biofilm communities in the anammox DMBRs, informing the precise regulation of membrane biofilms for improved nitrogen removal in anammox applications of wastewater treatment.}, }
@article {pmid39831829, year = {2025}, author = {Xin, H and Cai, Z and Hao, J and An, J and Li, Y and Wen, M and Jia, Z}, title = {Macro/Microgel-Encapsulated, Biofilm-Armored Living Probiotic Platform for Regenerating Bacteria-Infected Diabetic Wounds.}, journal = {Advanced healthcare materials}, volume = {}, number = {}, pages = {e2403476}, doi = {10.1002/adhm.202403476}, pmid = {39831829}, issn = {2192-2659}, support = {52201303//National Natural Science Foundation of China/ ; 22205012//National Natural Science Foundation of China/ ; JCYJ20220530145603007//Shenzhen Science and Technology Program/ ; JCYJ20220531091801003//Shenzhen Science and Technology Program/ ; 2023A1515012951//Guangdong Basic and Applied Basic Research Foundation/ ; 2020B1212060077//Foundation of Guangdong Provincial Key Laboratory of Sensor Technology and Biomedical Instrument/ ; 20241A011039//Western Medicine-General Guide Item of Guangzhou Municipal Health Commission/ ; 202201020637//Guangzhou Municipal Science and Technology Bureau Foundation/ ; }, abstract = {Infectious diabetic wounds pose an arduous threat to contemporary healthcare. The combination of refractory biofilms, persistent inflammation, and retarded angiogenesis can procure non-unions and life-threatening complications, calling for advanced therapeutics potent to orchestrate anti-infective effectiveness, benign biocompatibility, pro-reparative immunomodulation, and angiogenic regeneration. Herein, embracing the emergent "living bacterial therapy" paradigm, a designer probiotic-in-hydrogel wound dressing platform is demonstrated. The platform is constructed employing a "macrogel/microgel/biofilm" hierarchical encapsulation strategy, with Lactobacillus casei as the model probiotic. Alginate gels, in both macro and micro forms, along with self-produced probiotic biofilms, served as encapsulating agents. Specifically, live probiotics are enclosed within alginate microspheres, embedded into an alginate bulk matrix, and cultivated to facilitate biofilm self-encasing. This multiscale confinement protected the probiotics and averted their inadvertent escape, while enabling sustained secretion, proper reservation, and localized delivery of therapeutically active probiotic metabolites, such as lactic acid. The resulting biosystem, as validated in vitro/ovo/vivo, elicited well-balanced antibacterial activities and biological compatibility, alongside prominent pro-healing, vasculogenic and anti-inflammatory potencies, thus accelerating the regeneration of infected full-thickness excisional wounds in diabetic mice. Such multiple encapsulation-engineered "all-in-one" probiotic delivery tactic may shed new light on the safe and efficient adoption of live bacteria for treating chronic infectious diseases.}, }
@article {pmid39830521, year = {2024}, author = {Nielsen, SM and Johnsen, KK and Hansen, LBS and Rikvold, PD and Møllebjerg, A and Palmén, LG and Durhuus, T and Schlafer, S and Meyer, RL}, title = {Large-scale screening identifies enzyme combinations that remove in situ grown oral biofilm.}, journal = {Biofilm}, volume = {8}, number = {}, pages = {100229}, pmid = {39830521}, issn = {2590-2075}, abstract = {Bacteria in the oral cavity are responsible for the development of dental diseases such as caries and periodontitis, but it is becoming increasingly clear that the oral microbiome also benefits human health. Many oral care products on the market are antimicrobial, killing a large part of the oral microbiome but without removing the disease-causing biofilm. Instead, non-biocidal matrix-degrading enzymes may be used to selectively remove biofilm without harming the overall microbiome. The challenge of using enzymes to degrade biofilms is to match the narrow specificity of enzymes with the large structural diversity of extracellular polymeric substances that hold the biofilm together. In this study, we therefore perform a large-scale screening of single and multi-enzyme formulations to identify combinations of enzymes that most effectively remove dental biofilm. We tested >400 different treatment modalities using 44 different enzymes in combinations with up to six enzymes in each formulation, on in vitro biofilms inoculated with human saliva. Mutanase was the only enzyme capable of removing biofilm on its own. Multi-enzyme formulations removed up to 69 % of the biofilm volume, and the most effective formulations all contained mutanase. We shortlisted 10 enzyme formulations to investigate their efficacy against biofilms formed on glass slabs on dental splints worn by 9 different test subjects. Three of the ten formulations removed more than 50 % of the biofilm volume. If optimal enzyme concentration and exposure time can be reached in vivo, these enzyme combinations have potential to be used in novel non-biocidal oral care products for dental biofilm control.}, }
@article {pmid39830519, year = {2024}, author = {Turner, AB and Zermeño-Pérez, D and Mysior, MM and Giraldo-Osorno, PM and García, B and O'Gorman, E and Oubihi, S and Simpson, JC and Lasa, I and Ó Cróinín, T and Trobos, M}, title = {Biofilm morphology and antibiotic susceptibility of methicillin-resistant Staphylococcus aureus (MRSA) on poly-D,L-lactide-co-poly(ethylene glycol) (PDLLA-PEG) coated titanium.}, journal = {Biofilm}, volume = {8}, number = {}, pages = {100228}, pmid = {39830519}, issn = {2590-2075}, abstract = {Biodegradable polymeric coatings are being explored as a preventive strategy for orthopaedic device-related infection. In this study, titanium surfaces (Ti) were coated with poly-D,L-lactide (PDLLA, (P)), polyethylene-glycol poly-D,L-lactide (PEGylated-PDLLA, (PP20)), or multi-layered PEGylated-PDLLA (M), with or without 1 % silver sulfadiazine. The aim was to evaluate their cytocompatibility, resistance to Staphylococcus aureus biofilm formation, and their potential to enhance the susceptibility of any biofilm formed to antibiotics. Using automated high-content screening confocal microscopy, biofilm formation of a clinical methicillin-resistant Staphylococcus aureus (MRSA) isolate expressing GFP was quantified, along with isogenic mutants that were unable to form polysaccharidic or proteinaceous biofilm matrices. The results showed that PEGylated-PDLLA coatings exhibited significant antibiofilm properties, with M showing the highest effect. This inhibitory effect was stronger in S. aureus biofilms with a matrix composed of proteins compared to those with an exopolysaccharide (PIA) biofilm matrix. Our data suggest that the antibiofilm effect may have been due to (i) inhibition of the initial attachment through microbial surface components recognising adhesive matrix molecules (MSCRAMMs), since PEG reduces protein surface adsorption via surface hydration layer and steric repulsion; and (ii) mechanical disaggregation and dispersal of microcolonies due to the bioresorbable/degradable nature of the polymers, which undergo hydration and hydrolysis over time. The disruption of biofilm morphology by the PDLLA-PEG co-polymers increased S. aureus susceptibility to antibiotics like rifampicin and fusidic acid. Adding 1 % AgSD provided additional early bactericidal effects on both biofilm and planktonic S. aureus. Additionally, the coatings were cytocompatible with immune cells, indicating their potential to enhance bacterial clearance and reduce bacterial colonisation of titanium-based orthopaedic biomaterials.}, }
@article {pmid39829200, year = {2025}, author = {Li, WD and Lin, F and Sun, Y and Zhu, ZJ and Luo, ML and Zeng, YQ and Lin, Z and Zhou, M}, title = {Effect of platelet-rich plasma and platelet-rich fibrin on healing of burn wound with dual-species biofilm.}, journal = {The Kaohsiung journal of medical sciences}, volume = {}, number = {}, pages = {e12940}, doi = {10.1002/kjm2.12940}, pmid = {39829200}, issn = {2410-8650}, support = {2022NZC008//Platelet Rich Plasma Gel Combined with Silver Ion in the Treatment of Infectious Diseases Feasibility Study of Wounds/ ; 20QNPY079//Development of Portable Emergency Blood Collection Function Box Group in Field Conditions/ ; B2021019//Inhibitory Effect of Platelet Rich Fibrin on Bacterial Biofilm of Scald Wound in Rats/ ; }, abstract = {This study evaluated the impact of platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) on burn wound with dual-species biofilm. Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus) were applied to infect the burn wound in rats to establish a dual-species biofilm model. After infection, the wound was treated with ionized silver (AG), PRF, and PRP. Silver scanning electron microscopy (SEM) was used to assess adhesion after infection. PRF and PRP reduced wound size from day 8 after burn injuries, while AG significantly promoted burn wound healing at day 12. New collagen was formed in the shortest time in PRF and PRP groups compared to AG and control groups. PRF and PRP greatly lowered the bacterial numbers in wounds with S. aureus and P. aeruginosa biofilm, whereas AG showed weak bacteriostatic effects. AG, PRF, and PRP treatments significantly reduced inflammatory mediators and induced VEGFA. However, AG treatment increased TNF-α. PRF and PRP accelerate wound healing in the presence of dual-species biofilm infection and show strong antibacterial activity against S. aureus and P. aeruginosa, indicating that PRF and PRP could be potential therapies for burn wounds with dual-species biofilm infection.}, }
@article {pmid39828459, year = {2025}, author = {Cordisco, E and Serra, DO}, title = {Moonlighting antibiotics: the extra job of modulating biofilm formation.}, journal = {Trends in microbiology}, volume = {}, number = {}, pages = {}, doi = {10.1016/j.tim.2024.12.011}, pmid = {39828459}, issn = {1878-4380}, abstract = {The widespread use of antibiotics to treat bacterial infections has led to the common perception that their only function is to inhibit growth or kill bacteria. However, it has become clear that when antibiotics reach susceptible bacteria at non-lethal concentrations, they perform additional functions that significantly impact bacterial physiology, shaping both individual and collective behaviors. A key bacterial behavior influenced by sub-lethal antibiotic doses is biofilm formation, a multicellular, surface-associated mode of growth. This review explores different contexts in which natural and clinical antibiotics act as modulators of bacterial biofilm formation. We discuss cases that provide mechanistic insights into antibiotic modes of action, highlighting emerging common patterns and novel findings that pave the way for future research.}, }
@article {pmid39828045, year = {2025}, author = {Li, D and Wang, S and Liu, G and Zeng, EY}, title = {Dual intermittent aerations enhance nitrogen removal via anammox in anoxic/oxic biofilm process for carbon limited wastewater treatment.}, journal = {Bioresource technology}, volume = {419}, number = {}, pages = {132096}, doi = {10.1016/j.biortech.2025.132096}, pmid = {39828045}, issn = {1873-2976}, mesh = {*Biofilms ; *Nitrogen/metabolism ; *Wastewater/chemistry ; *Bioreactors ; *Water Purification/methods ; *Carbon/metabolism ; *Denitrification ; Nitrification ; Oxidation-Reduction ; Anaerobiosis ; Bacteria/metabolism ; Waste Disposal, Fluid/methods ; }, abstract = {Efficient nitrogen removal after organic capture is challenging through conventional nitrification-denitrification process. Two biofilm-based anoxic/oxic reactors, with a single intermittent zone (R1) or dual intermittent zones (R2), were compared in treating carbon-limited wastewater. Intermittent aeration integrated partial nitrification-anammox (PNA), partial denitrification-anammox (PDA), and denitrification, with anammox-related pathways contributing over 75% nitrogen removal in both reactors. As nitrogen loading rate increased from 0.14 to 0.19 kg-N m[-3] day[-1], nitrogen removal efficiency in R1 dropped from 74.3% to 46.0%, while R2 maintained 76.6% removal at low HRT of 6 h. The dual intermittent aeration strategy improved nitrogen removal capacity by enhancing PNA in the first intermittent zone and reducing effluent fluctuation in the second. Anammox bacteria (Candidatus Brocadia, relative abundance: 0.95-2.48%) were enriched across all zones, supporting efficient PNA and PDA. These findings suggested that dual intermittent aeration enhanced anammox in pre-anoxic processes for carbon limited wastewater treatment.}, }
@article {pmid39828044, year = {2025}, author = {Carluccio, M and Sabatino, R and Borgomaneiro, G and Cesare, AD and Rizzo, L}, title = {Bacterial community dynamics in a biofilm-based process after electro-assisted Fenton pre-treatment of real olive mill wastewater.}, journal = {Bioresource technology}, volume = {419}, number = {}, pages = {132095}, doi = {10.1016/j.biortech.2025.132095}, pmid = {39828044}, issn = {1873-2976}, mesh = {*Biofilms ; *Olea ; *Wastewater/chemistry/microbiology ; *Bacteria ; Iron/pharmacology/chemistry ; Hydrogen Peroxide/pharmacology ; Bioreactors/microbiology ; Water Purification/methods ; Industrial Waste ; Biodegradation, Environmental ; }, abstract = {In this work, the effect of the electro-assisted Fenton (EAF) process on the bacterial community of a moving bed biofilm reactor (MBBR) for olive mill wastewater (OMW) co-treatment with urban wastewater (UWW) was investigated. According to metagenomic analysis, pre-treatment by EAF, while removing total phenols (TPHs) up to 84 % ± 3 % and improving biodegradability of OMW from 0.38 to 0.62, led to the emergence of bacterial genera in the MBBR (R2) that were not detected under conditions without pre-treatment (R1). Indeed, in that condition, Candidatus Competibacter replaced Amaricoccus as dominant denitrifying bacteria. In both cases, the bacterial community composition matched with high simultaneous nitrification-denitrification efficiency (up to 98 %). Finally, Chlorobium (2.5-4.1 %), sulphate-reducing bacteria and Geobacter (up to 1.6 ± 0.4 %), anaerobic bacteria that utilise iron oxides, were observed exclusively with EAF application, suggesting potential for the development of new integrated microbial electrochemical systems.}, }
@article {pmid39828003, year = {2025}, author = {Xie, D and Xu, L and Yuan, S and Yan, J and Zhou, P and Dong, W and Ma, J and Chen, C}, title = {Synthesis and biofilm inhibitory activity of cyclic dinucleotide analogues prepared with macrocyclic ribose-phosphate skeleton.}, journal = {Bioorganic &amp; medicinal chemistry letters}, volume = {119}, number = {}, pages = {130107}, doi = {10.1016/j.bmcl.2025.130107}, pmid = {39828003}, issn = {1464-3405}, abstract = {Cyclic diguanosine monophosphate (c-di-GMP) is the key second messenger regulating bacterial biofilm formation related genes. Several c-di-GMP analogues have demonstrated biofilm inhibition activity. In this study, ribose-phosphate macrocyclic skeleton containing 1'-azido groups was constructed, and CDN analogues were prepared via click chemistry. The biofilm formation inhibition activity of the analogues was evaluated, and compound 17 illustrated better activity than c-di-GMP. This high-throughput strategy could be extended to synthesize cyclic analogues for biological research and immunotherapeutic development.}, }
@article {pmid39827797, year = {2025}, author = {Wang, Y and Gao, J and Wang, Z and Zhao, Y and Wang, H and Guo, Y and Yuan, Y and Chen, H}, title = {Unignorable environmental risks: Insight into differential responses between biofilm and plastisphere in sulfur autotrophic denitrification system upon exposure to quaternary ammonium compounds.}, journal = {Journal of hazardous materials}, volume = {487}, number = {}, pages = {137231}, doi = {10.1016/j.jhazmat.2025.137231}, pmid = {39827797}, issn = {1873-3336}, abstract = {Concerns of quaternary ammonium compounds (QACs) and microplastics (MPs) as emerging containments accumulating in wastewater treatment plants (WWTPs) have attracted much attention. Plastisphere with distinctive microbial communities might also be the repository for pathogens and resistance genes (RGs). Thus, the effects of three representative QACs with different concentrations on biofilm and plastisphere were studied in sulfur autotrophic denitrification (SAD) system. Over 100 days, 1-5 mg/L QACs exerted few impacts on system stability, whereas 15 mg/L QACs seriously lowered the microbial activity and the inhibitory effects ranked: benzylalkyldimethylethyl ammonium compound > dialkyldimethyl ammonium compound > alkyltrimethyl ammonium compound. Dosing of QACs in SAD system not only altered the microbial community structure and assembly, but also induced higher levels of intracellular RGs and extracellular RGs in plastisphere than in biofilm. Although the free RGs abundances in water slightly lowered, they might also pose great ecological risks. Pathogens identified as the potential hosts of RGs were more prone to colocalizing in plastisphere. Mobile genetic elements directly contributed to the three-fraction RGs transmission in SAD system. This study offered new insights into the differential responses of biofilm and plastisphere under QACs stress and guided for the disinfectants and MPs pollution containment in WWTPs.}, }
@article {pmid39827548, year = {2025}, author = {Kar, A and Mukherjee, SK and Hossain, ST}, title = {Regulatory role of PA3299.1 small RNA in Pseudomonas aeruginosa biofilm formation via modulation of algU and mucA expression.}, journal = {Biochemical and biophysical research communications}, volume = {748}, number = {}, pages = {151348}, doi = {10.1016/j.bbrc.2025.151348}, pmid = {39827548}, issn = {1090-2104}, mesh = {*Biofilms/growth &amp; development ; *Pseudomonas aeruginosa/genetics/metabolism/physiology ; *Gene Expression Regulation, Bacterial ; *Bacterial Proteins/genetics/metabolism ; *RNA, Bacterial/genetics/metabolism ; RNA, Small Untranslated/genetics/metabolism ; }, abstract = {Small RNAs (sRNAs) have emerged as key regulators of transcriptional factors and components within regulatory networks that govern bacterial biofilm formation. This study aimed to explore the regulatory role of the PA3299.1 sRNA in controlling biofilm formation in P. aeruginosa. Results showed that PA3299.1 expression was significantly elevated in both substratum-attached and colony biofilms compared to planktonic growth. Further investigation revealed that strains overexpressing PA3299.1 exhibited enhanced biofilm formation, while its deletion resulted in a substantial reduction in biofilm development. PA3299.1 was found to regulate the expression of AlgU and MucA, the sigma and anti-sigma factors, integral to the biofilm developmental network. In summary, this research identifies PA3299.1 as a critical regulator of biofilm formation and potentially a contributor to the pathogenicity of P. aeruginosa, that could help to develop new therapeutic strategies to manage biofilm-associated infections.}, }
@article {pmid39827354, year = {2025}, author = {Liu, H and Wang, X and Wang, Z and Shen, Y}, title = {Evaluation of bacterial biofilm, smear layer, and debris removal efficacy of a hydro-dynamic cavitation system with physiological saline using a new ex vivo model: a CLSM and SEM study.}, journal = {BMC oral health}, volume = {25}, number = {1}, pages = {95}, pmid = {39827354}, issn = {1472-6831}, mesh = {*Biofilms/drug effects ; *Smear Layer ; *Microscopy, Confocal ; *Microscopy, Electron, Scanning ; Humans ; *Root Canal Irrigants/therapeutic use ; *Sodium Hypochlorite/therapeutic use/pharmacology ; *Dentin/microbiology ; Saline Solution ; In Vitro Techniques ; Root Canal Preparation/methods/instrumentation ; Edetic Acid/therapeutic use ; Needles ; Dental Pulp Cavity/microbiology ; }, abstract = {INTRODUCTION: To evaluate the bacterial biofilm, smear layer and debris removal efficacy of a hydro-dynamic cavitation system with physiological saline using a new ex vivo model.<br><br>METHODS: Seventy-five dentin discs were prepared from fifty-four extracted teeth. Seventy-five artificial root sockets were prepared. Sixty dentin discs were used to grow 3-week-old bacterial biofilms, while smear layer and debris were produced on fifteen dentin discs. These dentin discs were adhered to the middle third of the artificial root canals. The sixty ex vivo models with biofilm-covered dentin discs were divided into six groups: control, needle with physiological saline, ultrasonic with physiological saline, Odne&#x2122; Clean with physiological saline, needle with 3% NaOCl, and ultrasonic with 3% NaOCl. Biofilm removal efficacy was evaluated using confocal laser scanning microscopy. The fifteen ex vivo models with smear layer and debris-covered dentin discs were divided into three groups: control, Odne&#x2122; Clean with physiological saline, and 5% NaOCl followed by 17% EDTA. Smear layer and debris removal efficacy was evaluated using scanning electron microscopy. Statistical analysis was performed using one-way analysis of variance for comparisons involving more than two groups. Post-hoc pairwise comparisons were conducted using the Tukey test.<br><br>RESULTS: Odne[TM]Clean with physiological saline (98%) performed significantly better than needle irrigation (47%) or ultrasonic activation (54%) with physiological saline (P&#x2009;<&#x2009;0.05). Odne[TM]Clean with physiological saline removed biofilms as effectively as needle irrigation (97%) or ultrasonic activation (98%) with 3% NaOCl (P&#x2009;>&#x2009;0.05). Additionally, 5% NaOCl followed by 17% EDTA (score: 1.33) removed the smear layer significantly better than Odne[TM]Clean with physiological saline (score: 4.47) (P&#x2009;<&#x2009;0.05). However, Odne[TM]Clean with physiological saline (score: 1.27) removed debris as effectively as 5% NaOCl followed by 17% EDTA (score: 1.13) (P&#x2009;>&#x2009;0.05).<br><br>CONCLUSIONS: Odne[TM]Clean with physiological saline can effectively remove bacterial biofilm and debris from the dentin surface but cannot effectively remove the smear layer. Utilizing Odne[TM]Clean during the final irrigation may enhance root canal cleaning efficacy.}, }
@article {pmid39827346, year = {2025}, author = {Mustafa, S and Meheissen, MA and Moussa, S and ElBackly, R}, title = {Effect of ultrasonically-activated irrigation protocols used for regenerative endodontics on removal of dual species biofilm in a three-dimensionally printed tooth model: in vitro study.}, journal = {BMC oral health}, volume = {25}, number = {1}, pages = {98}, pmid = {39827346}, issn = {1472-6831}, mesh = {*Biofilms/drug effects ; *Printing, Three-Dimensional ; *Therapeutic Irrigation/methods ; *Enterococcus faecalis/drug effects ; *Root Canal Irrigants/pharmacology/therapeutic use ; Humans ; *Regenerative Endodontics/methods ; *Sodium Hypochlorite/pharmacology/therapeutic use ; In Vitro Techniques ; Streptococcus mutans/drug effects ; Models, Dental ; Dental Pulp Cavity/microbiology ; Ultrasonics ; }, abstract = {INTRODUCTION: Eradication of residual biofilm from root canal dentine is critical for the success of regenerative endodontic procedures (REPs).<br><br>THE AIM OF THE STUDY: To evaluate the influence of ultrasonically activated irrigants in concentrations used for REPs for removal of dual-species biofilm from three-dimensionally printed tooth models with attached dentine samples.<br><br>METHODOLOGY: Seventy-two three-dimensionally printed teeth models were fabricated with a standardized slot in the apical third of the root to ensure a precise fit with a human root dentine specimen. Dual-species biofilms (comprising&#xa0;Enterococcus faecalis and Streptococcus mutans) were cultivated in the root canal for a period of three weeks. Models with dentine specimens were randomly assigned into 5 groups according to the irrigation protocol; G1(dis H2O): infected root canals irrigated with distilled water to serve as controls; G2(1.5% NaOCl): 1.5% NaOCl for five minutes; G3(1.5% NaOCl&#x2009;+&#x2009;PUI): 1.5% NaOCl&#x2009;+&#x2009;passive ultrasonic irrigation (PUI) for 30&#xa0;s; G4(3% NaOCl): 3% NaOCl for five minutes; G5(3% NaOCl&#x2009;+&#x2009;PUI): 3% NaOCl&#x2009;+&#x2009;PUI for 30&#xa0;s. Bacterial reduction was determined by colony-forming unit (CFU) counting (n&#x2009;=&#x2009;12/G), whilst biofilms were analyzed using field emission scanning electron microscopy in additional samples.<br><br>RESULTS: The four experimental groups showed a significant reduction in CFU counts compared to the control group (p&#x2009;<&#x2009;0.05). When compared with (dis H2O), the highest reduction in bacterial count was obtained in G5 (3% NaOCl&#x2009;+&#x2009;PUI) followed by G4 (3% NaOCl), then G3 (1.5% NaOCl&#x2009;+&#x2009;PUI), and finally G2 (1.5% NaOCl).<br><br>CONCLUSION: Results of the current study propose that a 3D-printed mature tooth model can be effectively used to analyze the antimicrobial effects of different irrigation protocols on dual-species biofilm. The use of NaOCl in concentrations used for regenerative endodontics can effectively remove bacterial biofilms. Furthermore, the use of PUI did not significantly enhance antibacterial effects of NaOCl.}, }
@article {pmid39826397, year = {2025}, author = {Lakshminarasimman, N and Zamanzadeh, M and Schraa, O and Parker, W}, title = {Modeling nitrous oxide emission from full-scale hybrid membrane aerated biofilm reactors (MABR).}, journal = {Water research}, volume = {274}, number = {}, pages = {123128}, doi = {10.1016/j.watres.2025.123128}, pmid = {39826397}, issn = {1879-2448}, abstract = {Current published models for nitrous oxide (N2O) emission in membrane aerated biofilm reactors (MABR) have several simplifications that are not representative of full-scale systems. This study developed an improved MABR N2O model that captured commonly overlooked phenomena such as back diffusion of generated N2O into MABR lumen gas and the recirculation of the N2O laden lumen gas for tank mixing and biofilm thickness control. The improved model was validated with measured N2O concentrations in the lumen gas phase and bulk mixed liquor in a full-scale hybrid MABR facility. The validated model was used to obtain insights into N2O bioconversion pathways. Model predictions revealed that in the inner layers of the biofilm were hotspots of N2O generation via the ammonium oxidizing organism activity. The N2O transported to the outer biofilm layers was reduced via the heterotrophic denitrification pathway. The N2O gas model predicted that up to 70 % of the N2O carried by the recirculated lumen gas was scrubbed into the mixed liquor which was further denitrified. An N2O emission ratio of 0.18 ± 0.01 % N2ON/N load was estimated for the full-scale MABR process which achieved up to 50 % removal of the influent N load, highlighting the potential of this technology to mitigate N2O emissions when compared to conventional activated sludge.}, }
@article {pmid39825489, year = {2025}, author = {Chen, X and Yang, R and Liu, K and Liu, M and Shi, Q and Yang, J and Hao, G and Luo, L and Du, F and Wang, P}, title = {From Natural Product Derivative to Hexagonal Prism Supermolecule: Potent Biofilm Disintegration, Enhanced Foliar Affinity, and Effective Management of Tomato Bacterial Canker.}, journal = {Angewandte Chemie (International ed. in English)}, volume = {}, number = {}, pages = {e202416079}, doi = {10.1002/anie.202416079}, pmid = {39825489}, issn = {1521-3773}, support = {2022YFD1700300//National Key Research and Development Program/ ; No. GCC[2023]008//Innovation Program for High-level Talents of Guizhou Province/ ; ZK[2022]017//Guizhou Provincial S&amp;T Project/ ; Guidakechuangtuan[2023]03//Research and Innovation Team of Guizhou University/ ; Guidazhuanjihe[2024]02//Natural Science Special Project of Guizhou University/ ; Qiankehezhongyindi (2023) 001//Central Government Guides Local Science and Technology Development Fund Projects/ ; 111 Program, D20023//Program of Introducing Talents of Discipline to Universities of China/ ; }, abstract = {Clavibacter michiganensis (Cmm), designated as an A2 quarantine pest by the European and Mediterranean Plant Protection Organization (EPPO), incites bacterial canker of tomato, which presently eludes rapid and effective control methodologies. Dense biofilms formed by Cmm shield internal bacteria from host immune defenses and obstruct the ingress of agrochemicals. Even when agrochemicals disintegrate biofilms, splashing and bouncing during application disperse active ingredients away from target sites. Herein, we present a supramolecular strategy to fabricate a hexagonal prism-shaped material, BPGA@CB[8], assembled from an 18β-glycyrrhetinic acid derivative (PBGA) and host molecule-cucurbit[8]uril (CB[8]) via host-guest recognition. This positively charged material manifests multifaceted functionalities, notably the ability to surmount biofilm barriers, annihilate the encased pathogenic bacteria, and enhance foliar affinity of droplets. The strong in vitro potency and effective deposition of BPGA@CB[8] foster optimal conditions for robust in vivo efficacy, demonstrating superior protective and curative activities (56.9 %/53.4 %) against canker of tomato at a low-dose of 100 μg⋅mL[-1] compared to BPGA (44.6 %/42.2 %), kasugamycin (30.1 %/28.4 %), and thiodiazole copper (35.4 %/31.0 %). This supramolecular material, based on natural product derivatives, provides a potent treatment for high-risk canker of tomato, and exemplifies the utility of supramolecular strategies in optimizing the attributes of natural products for managing plant bacterial diseases.}, }
@article {pmid39824742, year = {2025}, author = {Das, MC and Samaddar, S and Jawed, JJ and Ghosh, C and Acharjee, S and Sandhu, P and Das, A and Daware, AV and De, UC and Majumdar, S and Das Gupta, SK and Akhter, Y and Bhattacharjee, S}, title = {Corrigendum to "Vitexin alters Staphylococcus aureus surface hydrophobicity to obstruct biofilm formation" [Microbiol. Res. 263 (2022) 127126].}, journal = {Microbiological research}, volume = {}, number = {}, pages = {128058}, doi = {10.1016/j.micres.2025.128058}, pmid = {39824742}, issn = {1618-0623}, }
@article {pmid39824400, year = {2025}, author = {Ren, P and Dong, Q and Zhou, C and Chen, T and Sun, W and Chen, Y and Ying, H}, title = {Enhanced pullulanase production through expression system optimization and biofilm-immobilized fermentation strategies.}, journal = {International journal of biological macromolecules}, volume = {}, number = {}, pages = {139933}, doi = {10.1016/j.ijbiomac.2025.139933}, pmid = {39824400}, issn = {1879-0003}, abstract = {Pullulanase (PUL) plays a crucial role in breaking down α-1,6-glycosidic bonds in starch, a key process in starch processing and conversion. Based on PulB with high enzymatic activity, the expression of PUL in Bacillus subtilis was enhanced by plasmid screening, double promoter optimization, and signal peptide engineering. Furthermore, we innovatively employed a mussel foot protein to enhance the cell adhesion to carriers and utilized biofilm-based cell immobilization technology to optimize the fermentation process and stimulate biofilm formation. This approach led to a notably elevated enzyme activity, reaching 2233.56 U mL[-1]. The PUL crude enzyme solution, capable of generating high glucose syrup and resistant starch, paves the way for new avenues of exploration and advancement in research and industrial biotechnology.}, }
@article {pmid39823805, year = {2025}, author = {Lee, J and Park, J and Baek, J and Lee, S and Seo, E and Kim, S and Choi, H and Kang, SS}, title = {Spent coffee ground disrupts Listeria monocytogenes biofilm formation through inhibition of motility and adhesion via quorum sensing regulation.}, journal = {International journal of food microbiology}, volume = {430}, number = {}, pages = {111066}, doi = {10.1016/j.ijfoodmicro.2025.111066}, pmid = {39823805}, issn = {1879-3460}, mesh = {*Listeria monocytogenes/drug effects/physiology ; *Quorum Sensing/drug effects ; *Biofilms/drug effects/growth &amp; development ; *Bacterial Adhesion/drug effects ; *Coffee ; Humans ; Plant Extracts/pharmacology ; Hydrophobic and Hydrophilic Interactions ; Homoserine/analogs &amp; derivatives/metabolism/pharmacology ; Lactones ; }, abstract = {Spent coffee grounds (SCGs) have been explored for use as various bioresources, such as biofuels, and are known to possess biological functions, including antioxidant activity. However, the antibiofilm properties of SCGs against pathogenic bacteria have not been fully investigated. Therefore, this study aimed to highlight the inhibitory effects of SCG extract (SCGE) on biofilm formation in Listeria monocytogenes and investigated the underlying mechanisms. Treatment with SCGE disrupted both biofilm formation and architecture in L. monocytogenes. Furthermore, SCGE reduced autoaggregation and surface hydrophobicity. However, SCGE did not affect the viability of planktonic L. monocytogenes, suggesting that the decrease in biofilm formation was not attributed to decreased viability. Instead, SCGE downregulated motility- and adhesion-related genes in L. monocytogenes. Furthermore, SCGE impaired the swimming motility of L. monocytogenes. It also impaired adhesion to and invasion of intestinal epithelial cells. Moreover, SCGE suppressed the production of autoinducer-2, indicating the inhibition of quorum sensing signaling. Taken together, these findings suggest that SCGE inhibits biofilm formation in L. monocytogenes by modulating quorum sensing signaling, which regulates bacterial motility and adhesion.}, }
@article {pmid39821607, year = {2025}, author = {Santos Manzi de Souza, PF and Milanez, EPR and de Andrade, ARC and Silva, L and Silva, ML and Monteiro, RC and Rodrigues, AM and de Souza Collares Maia, DCB and de Melo Guedes, GM and de Aguiar Cordeiro, R}, title = {Antifungal susceptibility, clinical findings, and biofilm resistance of Fusarium species causing keratitis: a challenge for disease control.}, journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]}, volume = {}, number = {}, pages = {}, pmid = {39821607}, issn = {1678-4405}, support = {306295/2022-9//Conselho Nacional de Desenvolvimento Cient&#xed;fico e Tecnol&#xf3;gico/ ; }, abstract = {Fusarium keratitis (FK) is an important clinical condition that can lead to blindness and eye loss, and is most commonly caused by the Fusarium solani species complex (FSSC). This study evaluated the susceptibility of planktonic cells and biofilms of FSSC (n = 7) and non-FSSC (n = 7) isolates obtained from patients with keratitis from a semi-arid tropical region to amphotericin B (AMB), natamycin (NAT), voriconazole (VRZ), efinaconazole (EFZ), and luliconazole (LCZ). Analysis of clinical data showed that trauma was the most common risk factor for FK patients. Disease onset was longer in non-FSSC group (3-30 days) than in the FSSC group (3-7 days). FSSC strains were less susceptible to AMB and VRZ than non-FSSC strains (p < 0.05). Susceptibility to NAT, LCZ and EFZ was similar between isolates of FSSC and non-FSSC groups. Overall, patients infected with non-FSSC showed a better response to antifungal treatment. Corneal transplantation was more common in patients infected with FSSC (3/7) than in those infected with non-FSSC (1/7). Mature biofilms showed a poor response to antifungal treatment. Patients infected with Fusarium strains capable of forming antifungal tolerant biofilms had more complex therapeutic management, requiring two antifungals and/or corneal transplantation (p < 0.05). This study highlights the importance of mycological diagnosis and the antifungal susceptibility testing in the clinical management of FK. The ability of Fusarium to form antifungal tolerant biofilms poses a challenge to clinicians and urges the development of new antibiofilm therapeutics.}, }
@article {pmid39820867, year = {2025}, author = {Ertan, MB and Ayduğan, MY and Evren, E and İnanç, &#x130; and Erdemli, E and Erdemli, B}, title = {Differences of microbial growth and biofilm formation among periprosthetic joint infection-causing species: an animal study.}, journal = {International microbiology : the official journal of the Spanish Society for Microbiology}, volume = {}, number = {}, pages = {}, pmid = {39820867}, issn = {1618-1905}, support = {19L0230016//Ankara Universitesi/ ; 19L0230016//Ankara Universitesi/ ; 19L0230016//Ankara Universitesi/ ; 19L0230016//Ankara Universitesi/ ; 19L0230016//Ankara Universitesi/ ; 19L0230016//Ankara Universitesi/ ; }, abstract = {PURPOSE: The most frequently used surgical procedures for periprosthetic joint infections (PJIs) are debridement, antibiotics, and implant retention (DAIR), as well as single- or two-stage revision arthroplasty. The choice of surgery is made depending on the full maturation of the biofilm layer. The purpose of this study was to evaluate the biofilm formation and microbial growth using common PJI-causing agents and compare its development on the implant surface.<br><br>METHODS: The in vivo study was performed using 40 Sprague-Dawley rats divided into five groups (n&#x2009;=&#x2009;8/group): Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Candida albicans, and control. Six standard titanium alloy discs were placed into the subcutaneous air pouches of the interscapular areas of the rats. After the inoculation of microorganisms, disc and soft tissue cultures were collected at 2-week intervals for 6&#xa0;weeks, and the microbial load and the microscopic appearance of the biofilm were compared.<br><br>RESULTS: The disc samples from the S. aureus group had the highest infection load at all time points; however, in soft tissue samples, this was only observed at week 4 and 6. Electron microscopic images showed no distinctive differences in the biofilm structures between the groups.<br><br>CONCLUSION: S. aureus microbial burden was significantly higher in implant cultures at week 2 compared to other PJI-causing agents examined. These results may explain the higher failure rate seen if the DAIR procedure was performed at&#x2009;<&#x2009;3-4&#xa0;weeks after the PJI symptom onset and support the observation that DAIR may not be effective against PJIs caused by S. aureus.}, }
@article {pmid39820496, year = {2025}, author = {Freire, A and Bento, VAA and Jussiani, EI and Andrello, AC and Marques, MCS}, title = {Resin composite aggregated S-PRG particles are not superior to non-S-PRG under microcosm biofilm.}, journal = {Scientific reports}, volume = {15}, number = {1}, pages = {2173}, pmid = {39820496}, issn = {2045-2322}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Composite Resins/pharmacology/chemistry ; Humans ; Toothpastes/pharmacology/chemistry ; Dental Caries/microbiology/prevention &amp; control ; Dental Enamel/drug effects/microbiology ; Tooth Demineralization/prevention &amp; control/microbiology ; Molar/drug effects/microbiology ; Streptococcus mutans/drug effects/physiology/growth &amp; development ; Hardness ; Dentin/microbiology/drug effects ; }, abstract = {This study assessed the effect of composite resins, aggregated or not with S-PRG particles, and the use of toothpaste in controlling demineralization and bacterial growth. Human molars were distributed into 3 groups: control (CT) - sound teeth, Beautifil Bulk Restorative System (aggregated with S-PRG) (BB), Filtek One Bulk Fill (without S-PRG) (FB). Teeth destined for groups BB and FB previously received Class I preparations (4 × 4 × 4 mm), followed by single-increment restorations. All teeth were sectioned mesiodistally, with all specimens subjected to cariogenic challenge for 5 days, including microcosm biofilm formation. Half of each tooth was exposed to toothpaste (CTF, BBF, FBF). The loss of microhardness was assessed considering the initial microhardness as 100% on enamel, dentin, and composite resin substrates. Colony Forming Units (CFU/mL) were counted in 3 media. Data analysis used one-way ANOVA, Tukey HSD test, and paired t-test (α = 0.05). Toothpaste significantly reduced CFU/mL for total bacteria and genus Streptococcus (p < 0.05), with no significant difference for Streptococcus mutans. Enamel microhardness was positively affected by toothpaste. Both restorative systems controlled enamel demineralization, with FB and FBF outperforming BB and BBF. There was minor degradation of both composite resins, between 10% and 22%. Toothpaste effectively reduced microorganisms, irrespective of the composite resin. Regarding demineralization control, both restorative systems, with and without S-PRG particles, were effective on enamel.}, }
@article {pmid39819481, year = {2025}, author = {Guo, Y and He, J and Li, S and Zou, S and Zhang, H and Yang, X and Wang, J}, title = {Warm and humid environment induces gut microbiota dysbiosis and bacterial translocation leading to inflammatory state and promotes proliferation and biofilm formation of certain bacteria, potentially causing sticky stool.}, journal = {BMC microbiology}, volume = {25}, number = {1}, pages = {24}, pmid = {39819481}, issn = {1471-2180}, support = {2320004000279//Zhuhai City Social Development Sector Science and Technology Plan Project/ ; 2023A03J0268//the financial support from Guangzhou City Science and Technology Plan Project/ ; }, mesh = {Animals ; *Gastrointestinal Microbiome ; *Dysbiosis/microbiology ; Mice ; *Biofilms/growth &amp; development ; *Feces/microbiology ; *Bacterial Translocation ; *Humidity ; *Bacteria/classification/isolation &amp; purification/genetics ; Humans ; Inflammation ; Male ; China ; Medicine, Chinese Traditional ; Temperature ; Female ; }, abstract = {Fluctuations in environmental temperature and humidity significantly affect human physiology and disease manifestation. In the Lingnan region of China, high summer temperatures and humidity often cause symptoms like diminished appetite, sticky tongue coating, sticky stool, unsatisfactory defecation, lethargy, and joint heaviness. These are referred to as "Dampness Syndrome" in Traditional Chinese Medicine (TCM). Thick and greasy tongue fur and sticky feces are characteristic symptoms of "Dampness Syndrome" and serve as crucial diagnostic indicators in TCM for assessing health conditions. However, the specific mechanisms that lead to these symptoms, such as sticky feces and thick and greasy tongue fur, have not been fully elucidated. Understanding these external symptoms is essential, as they reflect internal health status. Warm, humid environments favor microorganism growth, potentially disrupting gut microbiota and bacterial translocation, which could induce an immune-inflammatory response. The primary objective of this study is to explore the potential significant role of immune response products in influencing the proliferation and biofilm formation of gut microbiota, which may subsequently lead to changes in fecal characteristics.<br><br>METHODS: In this study, mice were exposed to a controlled warm and humid environment (25&#x2009;&#xb1;&#x2009;3&#xa0;&#xb0;C with 95% humidity) for 16 days to simulate conditions associated with "Dampness Syndrome." After this period, Huoxiang Zhengqi Water, a traditional remedy, has been administrated for four days. On the one hand saliva and tongue coating samples were also taken from human subjects with "Dampness Syndrome" for microorganism culturing and to assess biofilm formation, on the other hand the co-culture products of a macrophage cell line RAW264.7 and Candida albicans and the effect of tumor necrosis factor-&#x3b1; (TNF-&#x3b1;) were evaluated for their impact on the proliferation and biofilm-forming abilities of different bacterial strains.<br><br>RESULTS: Compared to a control group, the treatment group exhibited significant changes in gut microbiota, including increased biofilm formation, which was mitigated by Huoxiang Zhengqi Water. In the model group, fungal translocation was observed, potentially triggering an inflammatory response. Intraperitoneal injections of various bacterial strains in mice reproduced the sticky stool characteristics. Both mice and human subjects with "Dampness Syndrome" displayed elevated serum levels of inflammatory cytokines TNF-&#x3b1; and interleukin-17&#xa0;A (IL-17A).&#xa0;Interestingly, Saliva samples from individuals with "Dampness Syndrome" showed elevated TNF-&#x3b1; levels, accompanied by thick and greasy tongue fur. Culturing samples from the tongue coating of individuals in the "Dampness Syndrome" group revealed an increased biofilm formation capability. C. albicans co-cultured with RAW264.7 cells increased TNF-&#x3b1; secretion, and the supernatant promoted pathogenic bacterial proliferation and biofilm formation. TNF-&#x3b1; specifically enhanced biofilm formation in microorganism like C. albicans and Staphylococcus aureus, with minimal effect on beneficial bacteria like Lacticaseibacillus paracasei and Lactiplantibacillus plantarum in the tested conditions.<br><br>CONCLUSIONS: These findings provided new insights into the biological mechanisms of 'Dampness Syndrome' and support the therapeutic role of Huoxiang Zhengqi Water in treating symptoms associated with microbial dysbiosis and inflammation. Additionally, they indicate that TNF-&#x3b1; seems to have selective effects in promoting the proliferation and biofilm formation of different microbial species.}, }
@article {pmid39818194, year = {2025}, author = {Ren, Y and Oleszkiewicz, JA and Uyaguari, M and Ferraz, F and Devlin, TR}, title = {Impact of fall ammonia fluctuations on winter nitrification in moving bed biofilm reactors.}, journal = {The Science of the total environment}, volume = {962}, number = {}, pages = {178499}, doi = {10.1016/j.scitotenv.2025.178499}, pmid = {39818194}, issn = {1879-1026}, mesh = {*Nitrification ; *Ammonia/metabolism ; *Biofilms ; *Bioreactors ; *Seasons ; *Waste Disposal, Fluid/methods ; Wastewater ; }, abstract = {This pilot-scale study investigated nitrifying moving bed biofilm reactors (MBBRs) in a post-lagoon treatment setup over two years to evaluate the impact of seasonal ammonia fluctuations on winter nitrification. In Year 2, reactors without fall ammonia starvation achieved significantly higher winter ammonia removal (97.2 ± 1.5 %) and surface area ammonia removal rates (SARR) (0.69 ± 0.06 g N/m[2]·d) compared to Year 1 (63.7 ± 2.5 % ammonia removal, SARR of 0.35 ± 0.04 g N/m[2]·d), demonstrating the critical role of fall ammonia availability for winter nitrification. Biofilms in Year 2 were thinner and denser, with higher biomass concentrations, potentially supporting more active biomass and improved substrate uptake. Seasonal shifts and diversity loss were observed within the biofilm microbial community, and nitrifiers were identified as Nitrosomonadaceae and Nitrospiraceae. Moreover, linear relationships were explored between winter ammonia removals and two ratios: (1) days with influent ammonia levels ≤ 5 mg N/L to days with temperatures above 5 °C, and (2) average ammonia concentration during fall to peak winter ammonia concentration. The modeling results indicated that winter ammonia removal performance could be enhanced by minimizing low-ammonia periods in the fall and maximizing pre-winter ammonia concentration. Overall, this study not only provided a deeper understanding of the year-round nitrifying MBBR process but also highlighted the importance of maintaining adequate substrate levels during fall to ensure sufficient biomass accumulation and activity for robust winter nitrification performance. These findings are essential for enhancing wastewater treatment performance in cold climates and offer practical guidance for optimizing biofilm-based nitrification systems.}, }
@article {pmid39817380, year = {2025}, author = {Ghai, S and Shrivastava, R and Jain, S}, title = {Computational Model to Predict Potential Therapeutic Targets Employing Generative Adversarial Networks for Analysis of Proteins Involved in Mycobacterium fortuitum Biofilm Formation.}, journal = {Current medicinal chemistry}, volume = {}, number = {}, pages = {}, doi = {10.2174/0109298673345515241122024326}, pmid = {39817380}, issn = {1875-533X}, abstract = {A planktonic population of bacteria can form a biofilm by adhesion and colonization. Proteins known as "adhesins" can bind to certain environmental structures, such as sugars, which will cause the bacteria to attach to the substrate. Quorum sensing is used to establish the population is dense enough to form a biofilm. This paper presents a comprehensive overview of our investigation into these processes, specifically focusing on Mycobacterium fortuitum, an emerging pathogen of increasing clinical relevance. In our study, we detailed the methodology employed for the proteomic analysis of M. fortuitum, as well as our innovative application of Generative Adversarial Networks (GANs). These advanced computational tools allow us to analyze complex data sets and identify patterns that might otherwise remain obscured. With a particular focus on the effectiveness of GAN, the identified proteins and their potential roles in the context of M. fortuitum's pathogenesis were discussed. The insights gained from this study can significantly contribute to our understanding of this emerging pathogen and pave the way for developing targeted interventions, potentially leading to improved diagnostic tools and more effective therapeutic strategies against M. fortuitum infection. The authors can achieve 95.43% accuracy for the generator and 87.89% for the discriminator. The model was validated by considering different Machine learning algorithms, reinforcing that integrating computational techniques with microbiological investigations can significantly enhance our understanding of emerging pathogens. Overall, this study emphasizes the importance of exploring the molecular mechanisms behind biofilm formation and pathogenicity, providing a foundation for future research that could lead to innovative solutions in combating infections caused by M. fortuitum and other similar pathogens.}, }
@article {pmid39816633, year = {2024}, author = {Abbass, J and Ashraf, M and Demirbilek, SK and Yıldız, M and Aner, H and Raza, A and Carlı, KT}, title = {Occurrence of biofilm forming fungal species and in vitro evaluation of anti-biofilm activity of disinfectants used in drinking water.}, journal = {Veterinary research forum : an international quarterly journal}, volume = {15}, number = {12}, pages = {651-656}, pmid = {39816633}, issn = {2008-8140}, abstract = {Fungal contamination in drinking water has garnered considerable attention over the past few decades, especially considering the detrimental consequences of pathogenic fungal species on both human and animal health. The formation of biofilms by certain species is a considerable factor contributing to the emergence of severe fungal infections. This research was designed to isolate and identify fungi, particularly those capable of forming biofilms from 150 samples of drinking water sourced from various locations. The isolated fungal species were tested for them in vitro biofilm formation using a microtitration plate method and the crystal violet assay was applied to quantify the established biofilms. The effectiveness of three disinfectants, namely ozone, chlorine, and hydrogen peroxide, in preventing the formation of biofilms by the most isolated fungal species was monitored. The findings indicated that Aspergillus species were the most prevalent in drinking water, comprising 63.33% (95/150) of the total number of fungal species identified. Aspergillus fumigatus and Aspergillus flavus were identified as the primary contributors to biofilm formation in drinking water distribution systems with prevalence rates of 41.00 and 34.00%, respectively, among all Aspergillus species. The outcomes of the in vitro studies demonstrated that the ozone disinfectant exhibited promising results in inhibiting fungal biofilms compared to chlorine and hydrogen peroxide. In conclusion, these findings provided valuable insights for water distribution authorities to develop effective regimens for controlling biofilm-forming fungal species using suitable antifungal biofilm disinfectants.}, }
@article {pmid39814763, year = {2025}, author = {Wittig, C and Wagner, M and Vallon, R and Crouzier, T and van der Wijngaart, W and Horn, H and Bagheri, S}, title = {The role of fluid friction in streamer formation and biofilm growth.}, journal = {NPJ biofilms and microbiomes}, volume = {11}, number = {1}, pages = {17}, pmid = {39814763}, issn = {2055-5008}, support = {ERC-CoG-101088639//EC | EU Framework Programme for Research and Innovation H2020 | H2020 Priority Excellent Science | H2020 European Research Council (H2020 Excellent Science - European Research Council)/ ; ERC-CoG-101088639//EC | EU Framework Programme for Research and Innovation H2020 | H2020 Priority Excellent Science | H2020 European Research Council (H2020 Excellent Science - European Research Council)/ ; 2020-04714//Vetenskapsr&#xe5;det (Swedish Research Council)/ ; 2020-04714//Vetenskapsr&#xe5;det (Swedish Research Council)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Bacillus subtilis/physiology/growth &amp; development ; *Friction ; Stress, Mechanical ; }, abstract = {Biofilms constitute one of the most common forms of living matter, playing an increasingly important role in technology, health, and ecology. While it is well established that biofilm growth and morphology are highly dependent on the external flow environment, the precise role of fluid friction has remained elusive. We grew Bacillus subtilis biofilms on flat surfaces of a channel in a laminar flow at wall shear stresses spanning one order of magnitude (τw = 0.068 Pa to τw = 0.67 Pa). By monitoring the three-dimensional distribution of biofilm over seven days, we found that the biofilms consist of smaller microcolonies, shaped like leaning pillars, many of which feature a streamer in the form of a thin filament that originates near the tip of the pillar. While the shape, size, and distribution of these microcolonies depend on the imposed shear stress, the same structural features appear consistently for all shear stress values. The formation of streamers occurs after the development of a base structure, suggesting that the latter induces a secondary flow that triggers streamer formation. Moreover, we observed that the biofilm volume grows approximately linearly over seven days for all shear stress values, with a growth rate inversely proportional to the wall shear stress. We develop a scaling model, providing insight into the mechanisms by which friction limits biofilm growth.}, }
@article {pmid39814109, year = {2025}, author = {Goswami, S and Ghosh, M and Roy, S and Basak, S and Bhattacharjee, S}, title = {Quercetin combined with ciprofloxacin and gentamicin inhibits biofilm formation and virulence in Staphylococcus aureus.}, journal = {Microbial pathogenesis}, volume = {200}, number = {}, pages = {107297}, doi = {10.1016/j.micpath.2025.107297}, pmid = {39814109}, issn = {1096-1208}, abstract = {Biofilm formation, extracellular substance synthesis, and virulence factor production all have a major impact on drug tolerance and infection propagation caused by Staphylococcus aureus. Flavonoid compounds have been explored as potential solutions to enhance antibiotic efficacy against the biofilm formation of pathogenic microbes. Quercetin (QER) has previously demonstrated antibacterial and antibiofilm properties. This study examines the potential of QER on enhancing the antibacterial, antibiofilm, and antivirulent potential of conventional antibiotics gentamicin (GEN), and ciprofloxacin (CIP) and aims to decipher the underlying mechanisms of action. Our research demonstrates that combining QER with GEN or CIP enhances their antibacterial activity, disrupts S. aureus cell membrane integrity, and increases reactive oxygen species production, leading to enhanced bacterial cell lysis. Furthermore, the combinatorial effect of QER with sub-MIC of GEN and CIP markedly inhibits biofilm formation, reduces viable cell counts, and diminishes the extracellular matrix components. The inhibition of biofilm after combinatorial treatment is confirmed through fluorescence microscopy and scanning electron microscopy. The study also found that QER-antibiotics combinations strongly reduce virulence characteristics in S. aureus, (spreading ability, protease, and hemolysin production) controlled by global key regulatory factors AgrA and SarA.Gene expression analysis revealed down regulation of key regulatory genes (sarA and agrA) and the virulence gene (hla). Molecular docking experiments have revealed the interaction between QER and the quorum sensing regulatory proteins SarA and AgrA, predicting another possible mechanism by which QER improves the anti-biofilm and antivirulence efficacy of GEN and CIP. Collectively, our findings indicate that QER enhances the efficacy of GEN and CIP antibiotics in reducing the antibiofilm and virulent characteristics of S. aureus, highlighting its potential as a broad-spectrum strategy for controlling S. aureus pathogenicity.}, }
@article {pmid39812721, year = {2025}, author = {Chao, CA and Khilnani, TK and Jo, S and Shenoy, A and Bostrom, MPG and Carli, AV}, title = {Not All Antiseptic Solutions Are Equivalent in Removing Biofilm: A Comparison Across Different Orthopaedic Surfaces.}, journal = {The Journal of bone and joint surgery. American volume}, volume = {107}, number = {2}, pages = {127-133}, doi = {10.2106/JBJS.23.01118}, pmid = {39812721}, issn = {1535-1386}, mesh = {*Biofilms/drug effects ; *Anti-Infective Agents, Local/pharmacology ; *Staphylococcus aureus/drug effects ; *Escherichia coli/drug effects ; Humans ; *Povidone-Iodine/pharmacology ; Hydrogen Peroxide/pharmacology ; Polymethyl Methacrylate ; Prosthesis-Related Infections/prevention &amp; control/microbiology ; Chlorhexidine/analogs &amp; derivatives/pharmacology ; Zirconium ; Arthroplasty, Replacement, Knee ; }, abstract = {BACKGROUND: Antiseptic solutions are commonly utilized during total joint arthroplasty (TJA) to prevent and treat periprosthetic joint infection (PJI). The purpose of this study was to investigate which antiseptic solution is most effective against methicillin-sensitive Staphylococcus aureus (MSSA) and Escherichia coli biofilms established in vitro on orthopaedic surfaces commonly utilized in total knee arthroplasty: cobalt-chromium (CC), oxidized zirconium (OxZr), and polymethylmethacrylate (PMMA).<br><br>METHODS: MSSA and E. coli biofilms were grown on CC, OxZr, and PMMA discs for 24 and 72 hours. Biofilm-coated discs were treated with control or various antiseptic solutions for 3 minutes. Solutions included 10% povidone-iodine, a 1:1 mixture of 10% povidone-iodine plus 3% hydrogen peroxide, diluted povidone-iodine, 0.05% chlorhexidine gluconate, and a surfactant-based formulation of ethanol, acetic acid, sodium acetate, benzalkonium chloride, and water. Following treatment, discs were sonicated to quantify adherent bacteria or underwent imaging with scanning electron microscopy to identify biofilm. Antiseptic solutions were considered efficacious if they produced a 3-log (1,000-fold) reduction in colony-forming units compared with controls.<br><br>RESULTS: On both OxZr and CC, 10% povidone-iodine with hydrogen peroxide eradicated all MSSA, and it achieved clinical efficacy on PMMA at both 24-hour MSSA biofilm (p < 0.0002) and 72-hour MSSA biofilm (p = 0.002). On 72-hour MSSA biofilm, 10% povidone-iodine eradicated all bacteria on OxZr and CC, and it achieved clinical efficacy on PMMA (p = 0.04). On 24-hour MSSA biofilm, 10% povidone-iodine achieved efficacy on all surfaces (all p < 0.01). The surfactant-based formulation only achieved clinical efficacy on 72-hour MSSA biofilms on CC (p = 0.04) and OxZr (p = 0.07). On 72-hour E. coli biofilm, 10% povidone-iodine with or without hydrogen peroxide achieved clinical efficacy on all surfaces. No other solution achieved clinical efficacy on either MSSA or E. coli.<br><br>CONCLUSIONS: Antiseptic solutions vary considerably in efficacy against bacterial biofilm. The 10% povidone-iodine solution with or without hydrogen peroxide consistently removed MSSA and E. coli biofilms on multiple orthopaedic surfaces and should be considered for clinical use.<br><br>CLINICAL RELEVANCE: Clinicians should be aware of the differences in the efficacy of antiseptic solutions on different orthopaedic surfaces when treating MSSA or E. coli biofilms.}, }
@article {pmid39812140, year = {2025}, author = {Martí, ML and Cano Aristizábal, V and Motrich, R and Valenti, LE and Giacomelli, CE}, title = {Defending Ti6Al4V against Biofilm Formation with Albumin Biofunctionalization.}, journal = {Langmuir : the ACS journal of surfaces and colloids}, volume = {41}, number = {3}, pages = {2089-2102}, doi = {10.1021/acs.langmuir.4c04867}, pmid = {39812140}, issn = {1520-5827}, mesh = {*Titanium/chemistry ; *Biofilms/drug effects ; *Alloys/chemistry ; Animals ; Surface Properties ; Albumins/chemistry/metabolism ; Humans ; Mice ; Bacterial Adhesion/drug effects ; Adsorption ; RAW 264.7 Cells ; Serum Albumin, Bovine/chemistry ; }, abstract = {Surface biofunctionalization with structurally perturbed albumin, as well as with other plasmatic proteins, inhibits the initial bacterial adhesion and biofilm formation, involved in numerous healthcare-associated infections. In fact, we have reported this protective effect with thermally treated plasmatic proteins, such as albumin and fibrinogen, adsorbed on flat silica surfaces. Here, we show that albumin biofunctionalization also works properly on flat Ti6Al4V substrates, which are widely used to fabricate medical devices. The protective effect is conserved even in biologically relevant fluids, containing other proteins that potentially adsorb onto and/or displace preadsorbed albumin from the biofunctionalized substrates. We further demonstrate that the presence of structurally perturbed albumin on the substrate does not trigger macrophage activation and the release of inflammatory mediators. Consequently, surface biofunctionalization with thermally perturbed albumin is a simple strategy to prepare antibacterial, nonimmunogenic medical devices.}, }
@article {pmid39811797, year = {2025}, author = {Høiby, N}, title = {Cystic fibrosis and the clinical biofilm revolution A survey of the Danish CF Center's contribution.}, journal = {Biofilm}, volume = {9}, number = {}, pages = {100246}, pmid = {39811797}, issn = {2590-2075}, abstract = {Biofilm infections are chronic infections which are difficult to diagnose. Biofilm infections are tolerant to antibiotics and the defense mechanisms of the host. Patients with the genetic disease cystic fibrosis (CF) produce viscid mucus in the respiratory tract and therefore suffer from chronic biofilm infections in their lungs and paranasal sinuses. The most important microorganism is the mucoid phenotype of Pseudomonas aeruginosa which causes chronic biofilm infections in the lungs of CF patients and untreated patients succumb as children if they contact this biofilm infection. Since CF patients are treated in CF Centers all over the world, it is possible to do longitudinal studies on epidemiology, pathophysiology, diagnosis, prevention and treatment of P. aeruginosa biofilm infection which is not possible if such patients are not followed in specialized centers. This survey describes the research through several decades in the Danish CF Center in Copenhagen which have changed the epidemiology, treatment, prophylaxis and prognosis of CF patients worldwide. Based on these results ESCMID Guidelines for diagnosis and treatment of biofilm infections were published which have influenced biofilm research and treatment in other areas.}, }
@article {pmid39811371, year = {2025}, author = {Mamun, FA and Kumar, R and Anwuta, KU and Das, S and Jaagura, M and Herodes, K and Kyrpel, T and Borzyszkowska, AF and Zielińska-Jurek, A and Vincevica-Gaile, Z and Burlakovs, J and Krauklis, AE and Azra, MN and Salauddin, M and Zhong, J and Tenno, T and Bester, K and Zekker, I}, title = {How resistant is anammox biofilm against antibiotics: A special insight into anammox response towards fluoroquinolones.}, journal = {Heliyon}, volume = {11}, number = {1}, pages = {e41339}, pmid = {39811371}, issn = {2405-8440}, abstract = {Elevated concentrations of pharmaceutically active compounds (PhACs) in the water bodies are posing a serious threat to the aquatic microbiota and other organisms. In this context, anaerobic ammonium oxidizing (anammox) bacteria carry a great potential to degrade PhACs through their innate metabolic pathways. This study investigates the influence of short-term exposure to lower and higher concentrations (0.8 mg L[-1], 0.06 mg L[-1], respectively) of antibiotics on the anammox process under distinct operational conditions (starvation/non-starvation) in moving bed biofilm reactor (MBBR). During batch operations that lasted for up to 6 h, the total nitrogen removal efficiency (TNRE) and total nitrogen conversion rate (TNCR) reached a maximum of 93 ± 5 % and 6.97 ± 1.30 mg N g[-1] TSS d[-1], respectively. Evidently, at higher PhAC levels, the anammox process was active, and up to 75 % PhAC removal efficiency was obtained within 6 h of the batch cycle. Most importantly, the anammox biofilm effectively eliminated the PhACs compounds, i.e., ciprofloxacin (CIP), ofloxacin (OFL), and norfloxacin (NOR) present at higher (0.8 mg L[-1]) and lower (0.06 mg L[-1]) total PhACs (sum of CIP, NOR, OFL) concentrations. Furthermore, 16S rRNA sequencing analyses showed a mixture of nitrifying, denitrifying, and anammox bacterial commodities enriched on the carriers' surface with a high relative abundance of Candidatus Brocadia, primarily responsible for catalyzing the anammox process. This study showed the intricate relationship between PhAC concentrations, TNCR, and antibiotic elimination in the wastewater treatment, and the results obtained set up a new breakthrough in wastewater treatment. Future research should investigate the mechanisms that underlie the anammox biofilms' resistance to various types of PhACs and investigate the long-term stability and scalability of this process with real wastewater influents.}, }
@article {pmid39810607, year = {2025}, author = {Liu, W and Gregory, RL and Yang, CC and Hamada, Y and Lin, WS}, title = {The effects of anodization and instrumentation on titanium abutment surface characteristics and biofilm formation.}, journal = {Journal of prosthodontics : official journal of the American College of Prosthodontists}, volume = {}, number = {}, pages = {}, doi = {10.1111/jopr.14009}, pmid = {39810607}, issn = {1532-849X}, support = {2022//ACP Education Foundation (ACPEF) Research Fellowship/ ; }, abstract = {PURPOSE: To assess the impact of anodization and instrumentation on titanium abutment surface characteristics (surface roughness and wettability) and biofilm formation (viability and mass).<br><br>MATERIALS AND METHODS: Titanium discs were obtained from pre-milled abutment blanks made of titanium-6aluminum-7niobium alloy. Polished samples were divided into three groups: un-anodized, gold-anodized, and pink-anodized. Instrumentation methods included no-instrumentation, air polishing, and titanium scaling treatment. Surface roughness was measured using an optical profilometer, and wettability was determined by measuring the contact angles using the sessile drop method with an optical tensiometer. Biofilm formation by Streptococcus sanguinis was evaluated based on the biofilm viability and mass. The biofilm viability was evaluated through colony-forming unit counting (CFU/mL), and biofilm mass was assessed with crystal violet staining (mean absorbance measured at 490&#xa0;nm, in optical density values). Sample surfaces before and after biofilm formation were also examined by scanning electron microscope (SEM). Two-way ANOVA was performed to determine the group differences, and Spearman's correlation (&#x3c1;) was used to analyze the correlation among surface roughness, wettability, and CFU/mL (&#x3b1;&#xa0;=&#xa0;0.05).<br><br>RESULTS: Pink anodization significantly increased surface roughness (0.38&#xa0;&#xb1;&#xa0;0.07&#xa0;&#xb5;m, p&#xa0;<&#xa0;0.001) compared to un-anodized samples (0.25&#xa0;&#xb1;&#xa0;0.01&#xa0;&#xb5;m), while gold anodization did not (0.24&#xa0;&#xb1;&#xa0;0.03&#xa0;&#xb5;m, p&#xa0;=&#xa0;0.301). Among pink-anodized groups, air polishing resulted in significantly lower surface roughness (0.33&#xa0;&#xb1;&#xa0;0.08&#xa0;&#xb5;m) compared to titanium scaling (0.51&#xa0;&#xb1;&#xa0;0.11&#xa0;&#xb5;m, p&#xa0;<&#xa0;0.001) and no instrument treatment (0.38&#xa0;&#xb1;&#xa0;0.07&#xa0;&#xb5;m, p&#xa0;=&#xa0;0.050). Anodization significantly increased wettability (p&#xa0;<&#xa0;0.001), while instrumentation with a titanium scaling decreased it (p&#xa0;<&#xa0;0.001). The combination of un-anodized samples and titanium scaling treatment showed the lowest wettability with the highest contact angle (70.72&#xa0;&#xb1;&#xa0;2.63&#xb0;). The biofilm viability, measured by CFU/mL, was significantly inhibited by anodization (p&#xa0;<&#xa0;0.001) and air polishing (p&#xa0;<&#xa0;0.001) while promoted by titanium scaling (p&#xa0;<&#xa0;0.001). Gold-anodized titanium discs subjected to air polishing exhibited the lowest CFU/mL (279,420&#xa0;&#xb1;&#xa0;16,300), while un-anodized samples instrumented with a titanium scaler had the highest CFU/mL (945,580&#xa0;&#xb1;&#xa0;13,580). Biofilm mass, quantified by optical density values, was significantly inhibited by anodization (p&#xa0;<&#xa0;0.001) as well as air polishing (p&#xa0;=&#xa0;0.001). A moderate negative correlation was observed between CFU and wettability (&#x3c1;&#xa0;=&#xa0;-0.55, p&#xa0;<&#xa0;0.001).<br><br>CONCLUSION: Gold- and pink-anodized titanium surfaces were more hydrophilic, leading to less biofilm formation than un-anodized ones. Biofilm formation was inhibited by air polishing while promoted by titanium scaling. Gold anodization combined with air polishing had the least biofilm formation and can be considered the preferred abutment anodization/instrumentation combination.}, }
@article {pmid39809829, year = {2025}, author = {Holicheva, AA and Kozlov, KS and Boiko, DA and Kamanin, MS and Provotorova, DV and Kolomoets, NI and Ananikov, VP}, title = {Deep generative modeling of annotated bacterial biofilm images.}, journal = {NPJ biofilms and microbiomes}, volume = {11}, number = {1}, pages = {16}, pmid = {39809829}, issn = {2055-5008}, mesh = {*Biofilms/growth &amp; development ; *Image Processing, Computer-Assisted/methods ; Bacteria/genetics/classification ; Deep Learning ; }, abstract = {Biofilms are critical for understanding environmental processes, developing biotechnology applications, and progressing in medical treatments of various infections. Nowadays, a key limiting factor for biofilm analysis is the difficulty in obtaining large datasets with fully annotated images. This study introduces a versatile approach for creating synthetic datasets of annotated biofilm images with employing deep generative modeling techniques, including VAEs, GANs, diffusion models, and CycleGAN. Synthetic datasets can significantly improve the training of computer vision models for automated biofilm analysis, as demonstrated with the application of Mask R-CNN detection model. The approach represents a key advance in the field of biofilm research, offering a scalable solution for generating high-quality training data and working with different strains of microorganisms at different stages of formation. Terabyte-scale datasets can be easily generated on personal computers. A web application is provided for the on-demand generation of biofilm images.}, }
@article {pmid39809607, year = {2025}, author = {Ghosh, C and Bhowmik, J and Ghosh, R and Das, MC and Sandhu, P and Kumari, M and Acharjee, S and Daware, AV and Akhter, Y and Banerjee, B and De, UC and Bhattacharjee, S}, title = {Corrigendum to "The anti-biofilm potential of triterpenoids isolated from Sarcochlamys pulcherrima (Roxb.) Gaud" [Microbial. Pathogenes. 139 (2020) 103901].}, journal = {Microbial pathogenesis}, volume = {}, number = {}, pages = {107284}, doi = {10.1016/j.micpath.2025.107284}, pmid = {39809607}, issn = {1096-1208}, }
@article {pmid39805164, year = {2025}, author = {Xu, L and Khan, A and Aqeel, SA and Alqahtani, A and AlSharif, L and Kijkla, P and Kumseranee, S and Punpruk, S and Gu, T}, title = {Distinguishing abiotic corrosion from two types of microbiologically influenced corrosion (MIC) using a new electrochemical biofilm/MIC test kit.}, journal = {Journal of environmental management}, volume = {374}, number = {}, pages = {124093}, doi = {10.1016/j.jenvman.2025.124093}, pmid = {39805164}, issn = {1095-8630}, mesh = {Corrosion ; *Biofilms ; *Steel/chemistry ; Pseudomonas aeruginosa ; Desulfovibrio ; Electrodes ; }, abstract = {Biofilms can cause biofouling, water quality deterioration, and transmission of infectious diseases. They are also responsible for microbiologically influenced corrosion (MIC) which can cause leaks, resulting in environmental disasters. A new disposable biofilm/MIC test kit was demonstrated to distinguish abiotic corrosion of carbon steel from MIC. It used two solid-state electrodes inside a standard 10 mL serum vial to form a miniature electrochemical cell. In this work, abiotic corrosion was exemplified using CO2 corrosion and acetic acid corrosion. Sulfate reducing Desulfovibrio ferrophilus IS5, nitrate reducing Pseudomonas aeruginosa, and an oilfield biofilm consortium were grown anaerobically as examples of MIC systems. Tafel curves from dual-half scans and continuous upward scans did not differ significantly in each of the two abiotic corrosion systems. However, obvious distortions in Tafel curve shapes with corrosion potentials (Ecorr) shifts and corrosion current density (icorr) deviations (Tafel skews) were observed in each of the three MIC systems. The polarization resistance (Rp) trend from linear polarization resistance (LPR) for an MIC system decreased in several days due to biofilm buildup while an abiotic system did not have this delay. The abiotic corrosion systems did not respond to electron mediators or biocide injections with negligible Rp changes, while electron mediators accelerated extracellular electron transfer-MIC but not metabolite-MIC, and biocide injection reduced MIC rates as reflected by Rp changes. The results in this work demonstrated that the new kit is a useful tool in MIC diagnosis, biofilm/MIC monitoring and assessment of biocide efficacy.}, }
@article {pmid39803325, year = {2025}, author = {Biswas, B and Asif, S and Puria, R and Thakur, A}, title = {A Novel and Robust Method for Investigating Fungal Biofilm.}, journal = {Bio-protocol}, volume = {15}, number = {1}, pages = {e5146}, pmid = {39803325}, issn = {2331-8325}, abstract = {Candida auris, labeled an urgent threat by the CDC, shows significant resilience to treatments and disinfectants via biofilm formation, complicating treatment/disease management. The inconsistencies in biofilm architecture observed across studies hinder the understanding of its role in pathogenesis. Our novel in vitro technique cultivates C. auris biofilms on gelatin-coated coverslips, reliably producing multilayer biofilms with extracellular polymeric substances (EPS). This method, applicable to other Candida species like C. glabrata and C. albicans, is cost-effective and mimics the niche of biofilm formation. It is suitable for high-throughput drug screening and repurposing efforts, aiding in the development of new therapeutics. Our technique represents a significant advancement in Candida biofilm research, addressing the need for consistent, reproducible biofilm models. We detail a step-by-step procedure for creating a substratum for biofilm growth and measuring biofilm thickness using confocal laser scanning microscopy (CLSM) and ultrastructure by scanning electron microscopy (SEM). This method provides consistent outcomes across various Candida species. Key features • The biofilm formed on gelatin surfaces mimics host conditions, replicating the multilayered structure and EPS, offering a more accurate model for studying C. auris biofilms. • This method is highly reproducible and suitable for drug screening and biofilm analysis through three-dimensional (3D) reconstruction. • This in vitro technique aids in studying biofilm formation, related virulence properties, and drug tolerance of C. auris and other Candida species. • The simple, cost-effective technique is ideal for screening novel inhibitors and repurposed drug libraries, facilitating the design/identification of new therapeutics against Candida species.}, }
@article {pmid39802671, year = {2024}, author = {Tang, Q and Zhang, H and Chandarajoti, K and Jiao, Z and Nie, L and Lv, S and Zuo, J and Zhou, W and Han, X}, title = {Design and synthesis of coumarin-based amphoteric antimicrobials with biofilm interference and immunoregulation effects.}, journal = {RSC medicinal chemistry}, volume = {}, number = {}, pages = {}, pmid = {39802671}, issn = {2632-8682}, abstract = {Bacterial infections pose a threat to human and animal health, and the formation of biofilm exacerbates the microbial threat. New antimicrobial agents to address this challenge are much needed. In this study, several new amphoteric compounds derived from the natural product coumarin were designed and synthesized by mimicking the structure and function of antimicrobial peptides. Strong inhibitory effect of 8b was observed on S. aureus 29213 and five isolated clinically positive strains, with an MIC value of 1-4 μg mL[-1], accompanied by the potential advantages of rapid sterilization and no drug resistance. The in vivo activity of 8b was supported by good antibacterial and anti-inflammatory effects in a mouse wound infection model. More importantly, good immunomodulatory effects, inhibition of biofilm formation, and biofilm clearance were detected in the treatment using 8b, which makes it a potential candidate antibacterial for controlling S. aureus infections forming biofilm.}, }
@article {pmid39802281, year = {2025}, author = {Zhang, N and Zeng, Y and Ye, J and Lin, C and Gong, X and Long, H and Chen, H and Xie, Z}, title = {RpoN mediates biofilm formation by directly controlling vps gene cluster and c-di-GMP synthetic metabolism in V. alginolyticus.}, journal = {Biofilm}, volume = {9}, number = {}, pages = {100242}, pmid = {39802281}, issn = {2590-2075}, abstract = {Vibrio alginolyticus is a prevalent pathogen in both humans and marine species, exhibiting high adaptability to various adverse environmental conditions. Our previous studies have shown that ΔrpoN formed three enhanced biofilm types, including spectacular surface-attached biofilm (SB), scattered pellicle biofilm (PB), and colony rugosity. However, the precise mechanism through which rpoN regulates biofilm formation has remained unclear. Based on the critical role of Vibrio exopolysaccharide (VPS) in biofilm formation, several genes related to the production and regulation of VPS were characterized in V. alginolyticus. Our findings from mutant strains indicated that VPS has complete control over the formation of rugose colony morphology and PB, while it only partially contributes to SB formation. Among the four transcriptional regulators of the vps gene cluster, vpsR and VA3545 act as promoters, whereas VA3546 and VA2703 function as repressors. Through transcriptome analysis and c-di-GMP concentration determination, VA0356 and VA3580 which encoded diguanylate cyclase were found to mediate the ΔrpoN biofilm formation. As a central regulator, rpoN governed biofilm formation through two regulatory pathways. Firstly, it directly bound to the upstream region of VA4206 to regulate the expression of the vps gene cluster (VA4206-VA4196). Secondly, it directly and indirectly modulated c-di-GMP synthesis gene VA3580 and VA0356, respectively, thereby affecting c-di-GMP concentration and subsequently influencing the expression of vps transcription activators vpsR and VA3545. Under conditions promoting SB formation, ΔrpoN was unable to thrive below the liquid level due to significantly reduced activities of three catalytic enzymes (ACK, ADH, and ALDH) involved in pyruvate metabolism, but tended to reproduce in air-liquid interface, a high oxygen niche compared to the liquid phase. In conclusion, both exopolysaccharide synthesis and oxygen-related metabolism contributed to ΔrpoN biofilm formation. The role of RpoN-mediated hypoxic metabolism and biofilm formation were crucial for comprehending the colonization and pathogenicity of V. alginolyticus in hosts, providing a novel target for treating V. alginolyticus in aquatic environments and hosts.}, }
@article {pmid39801747, year = {2025}, author = {Hideaki Uyeda, F and Quilles Vargas, G and Matias Malavazi, L and Tiemi Macedo, T and Paim de Abreu Paulo Gomes, A and Rocha Bueno, M and Henrique Moreira Paulo Tolentino, P and Aguiar da Silva, LD and Cristina Figueiredo, L and Awad Shibli, J and Bueno-Silva, B}, title = {Platelet-rich fibrin obtained from different protocols affects the formation of the in vitro multispecies subgingival biofilm associated with periodontitis.}, journal = {Journal of oral microbiology}, volume = {17}, number = {1}, pages = {2445598}, pmid = {39801747}, issn = {2000-2297}, abstract = {BACKGROUND: The aim of this article is to evaluate the effect of different portions of Platelet Rich Fibrin (PRF) membranes and liquid-PRF, prepared by two distinct protocols/centrifuges each, on the multispecies subgingival biofilm.<br><br>MATERIALS AND METHODS: PRF membranes and liquid-PRF were prepared using two protocols: centrifuge 1 uses fixed acceleration while centrifuge 2, progressive acceleration. PRF samples were introduced into device concurrently with 33-species bacterial inoculum. After seven days, biofilm metabolic activity (MA) and microbial profile were evaluated through colorimetric reaction and DNA-DNA hybridization, respectively.<br><br>RESULTS: Among PRF membranes, the ones from centrifuge 1 led to better reduction in MA, total biofilm, and F. periodonticum, P. gingivalis and T. forsythia counts when compared to untreated/centrifuge 2 treated biofilms. However, centrifuge 2 liquid-PRF reduced MA, total biofilm and F. periodonticum counts when compared to untreated/centrifuge 1 treated-biofilms.<br><br>CONCLUSION: PRF membrane and exhibited comparable antibiofilm activity. However, PRF distinct forms, obtained by same centrifugation protocol, may present different antimicrobial properties.}, }
@article {pmid39801468, year = {2025}, author = {Yu, L and Wang, H and Zhang, X and Xue, T}, title = {Two-component system UhpAB facilitates the pathogenicity of avian pathogenic Escherichia coli through biofilm formation and stress responses.}, journal = {Avian pathology : journal of the W.V.P.A}, volume = {}, number = {}, pages = {1-12}, doi = {10.1080/03079457.2024.2442704}, pmid = {39801468}, issn = {1465-3338}, abstract = {UhpAB increases the pathogenicity of APEC.UhpAB activates the expression of virulence genes fepG, ldrD, ycgV, and ydeI.UhpAB promotes biofilm formation and enhances stress tolerance.UhpAB contributes to APEC evading attack by the host immune system.}, }
@article {pmid39800325, year = {2025}, author = {Takeda, PY and Paula, CT and Dias, MES and Borges, ADV and Damianovic, MHRZ}, title = {Achieving stable nitrogen removal through mainstream partial nitrification, anammox and denitrification (SNAD) with a hybrid biofilm-granular reactor.}, journal = {Chemosphere}, volume = {372}, number = {}, pages = {144105}, doi = {10.1016/j.chemosphere.2025.144105}, pmid = {39800325}, issn = {1879-1298}, mesh = {*Denitrification ; *Biofilms ; *Bioreactors/microbiology ; *Nitrification ; *Nitrogen/metabolism ; *Wastewater/chemistry ; *Waste Disposal, Fluid/methods ; *Oxidation-Reduction ; Ammonium Compounds/metabolism ; Biomass ; Bacteria/metabolism ; Water Pollutants, Chemical/metabolism ; Nitrites/metabolism ; }, abstract = {Simultaneous partial nitrification, anammox, and denitrification (SNAD) process offers a promising method for the effective removal of carbon and nitrogen from wastewater. However, ensuring stability is a challenge. This study investigated operational parameters such as hydraulic retention time (HRT) and biomass retention to stabilize SNAD operation, transitioning from synthetic to anaerobically pre-treated municipal wastewater (APMW) in an upflow hybrid biofilm-granular reactor (UHR). The incorporation of hybrid biomass in the form of biofilms and granules resulted in a significant improvement in ammonium oxidation, increasing the efficiency from 45% to 60%. This outcome underscores the significance of biomass retention as a crucial parameter in achieving optimal performance. Furthermore, extending the HRT resulted in a significant improved nitrogen removal, increasing it from 40% (8h) to 70% (12h), which was attributed to the enhanced specific activities of ammonium-oxidizing bacteria (AOB) and anammox bacteria (AnAOB). Microbial characterization unveiled the emergence of partial denitrifiers (Thauera genus) and the suppression of nitrite-oxidizing bacteria (NOB) (Nitrospira genus) at low aeration rates (0.35 L min[-1].L[-1]reactor; estimated 0.5 mgDO.L[-1]). Notably, stable operation persisted throughout the experimental period, primarily due to the consistent nitrite supply from partial nitrification/denitrification. Our findings highlight the potential of innovative hybrid reactor configuration, for achieving stable and efficient SNAD performance in mainstream wastewater treatment.}, }
@article {pmid39800299, year = {2025}, author = {Pang, S and Cai, X and Yang, L and Zhou, J and Li, X and Xia, S}, title = {Microbial synergy mechanism of hydrogen flux influence on hydrogen-based partial denitrification coupled with anammox in a membrane biofilm reactor.}, journal = {Environmental research}, volume = {268}, number = {}, pages = {120827}, doi = {10.1016/j.envres.2025.120827}, pmid = {39800299}, issn = {1096-0953}, abstract = {The hydrogen-based partial denitrification coupled with anammox (H2-PDA) biofilm system effectively achieves low-carbon and high-efficiency biological nitrogen removal. However, the effects and biological interaction mechanism of H2 flux with the H2-PDA system have not yet been understood. This study assessed the effects of H2 flux on interactions among anammox bacteria (AnAOB), denitrifying bacteria (DB), and sulfate-reducing bacteria (SRB) coexisting in a H2-PDA system. Results showed the simultaneous removal of 40 mg/L ammonium nitrogen (NH4[+]-N) and 50 mg/L nitrate nitrogen (NO3[-]-N) in the H2-PDA system at a flux of 0.13-0.14 e[-] eq/(m[2]·d) without additional organic carbon. Candidatus_Brocadia was involved in H2 oxidation and was negatively associated with the heterotrophic Thauera genus (DB). The expression of nirS and dsrA was increased to 5.6 × 10[5] copies/gSS and 2.1 × 10[5] copies/gSS, respectively, with excessive H2 flux (0.17 e[-] eq/(m[2]·d). This study provides technical guidance for understanding and applying the H2-PDA technology for low-carbon wastewater treatment.}, }
@article {pmid39800292, year = {2025}, author = {Changlor, N and Inchana, C and Sabar, MA and Suyamud, B and Lohwacharin, J}, title = {Effects of relative microplastic-biochar sizes and biofilm formation on fragmental microplastic retention in biochar filters.}, journal = {Environmental research}, volume = {268}, number = {}, pages = {120834}, doi = {10.1016/j.envres.2025.120834}, pmid = {39800292}, issn = {1096-0953}, abstract = {Microplastics (MPs) pose significant risks to aquatic life and human health. Conventional water treatment is ineffective in removing MPs, demanding alternative technologies. Biochar exhibits a potential for removing MPs through adsorption and filtration. The efficiency of biochar derived from macadamia (Macadamia Integrifolia) nutshells on MP removal from contaminated water was assessed in fixed-bed column tests at environmentally relevant MP concentrations in upward flowing regime. Fragmental polyethylene MPs (50-100 and 100-300 μm) were tested on the effects of the operating conditions, the relative MP-biochar size ratios (0.05-0.14 and 0.13-0.36 for small and large MPs), and biofilm formation on their retention in the biochar bed. The interactions between MPs and biochar are apparently electrostatically repulsive. Small biochar demonstrated >78% removal of the MPs at flow rates of 2.78 × 10[-5], 2.78 × 10[-4], or 1.39 × 10[-3] m/s. Increasing the MP influent concentrations significantly increased the MP removal by the filter. The lower flow rates increase the MP removal with both MP influent concentrations and MP sizes, showing a maximum of 96% removal of small MP. The removal of large MPs by biochar filters (i.e. MP-biochar size ratio: 0.13-0.36) is significantly different when the highest flow rate is used. This difference moderates as the flow rates and MP size decline. Biofilm formation at its early stage altered the porous characteristics and surface morphology of the biochar and enhanced the MP removal. Overall, this study provides insights into the application of biochar filters in tertiary wastewater treatment.}, }
@article {pmid39798111, year = {2024}, author = {Pradhan, S and Yadav, G and Saha, S and Dhinsa, K and Sharma, A and Rai, A}, title = {Comparison of Streptococcus mutans biofilm formation, acidogenicity, and buffering capacity among human breast milk, plain packaged bovine milk, sweetened bovine milk, and infant formula: An in vitro study.}, journal = {Journal of the Indian Society of Pedodontics and Preventive Dentistry}, volume = {42}, number = {4}, pages = {328-335}, doi = {10.4103/jisppd.jisppd_373_24}, pmid = {39798111}, issn = {1998-3905}, mesh = {*Biofilms ; *Streptococcus mutans/physiology ; *Infant Formula/chemistry ; *Milk, Human/microbiology/chemistry ; Humans ; Cattle ; Animals ; *Milk/microbiology ; Buffers ; Hydrogen-Ion Concentration ; Infant ; In Vitro Techniques ; Sweetening Agents ; Sucrose ; }, abstract = {CONTEXT: Human milk provides nutrients for newborns, while breastfeeding is preferred, formula feeding can also provide necessary nutrition and after weaning, individuals of all ages frequently drink bovine milk. Bovine and human milk contain lactose as a carbohydrate source, and infant milk formulas are also designed the same. However, lactose is fermentable by Streptococcus mutans, much like sucrose but to a lower extent.<br><br>AIM: This study aims to compare the S. mutans biofilm formation, acidogenicity and buffering capacity among human milk, plain packaged bovine milk (PBM), sweetened PBM, and infant formula (IF).<br><br>SETTINGS AND DESIGN: Microbiological assays, experiments on biofilm formation, acidogenicity and buffering capacity were conducted six times.<br><br>SUBJECTS AND METHODS: Ten distinct solutions were used: Plain PBM, sweetened bovine milk (SBM), IF, human breast milk (HBM), brain-heart infusion (BHI) with added 10% sucrose (BHI), and five duplicate solutions containing S. mutans culture. Biofilm formation - Biofilm development was evaluated on 96-polystyrene flat bottom plates. Biofilm acidogenicity - pH of the biofilms was determined by dipping in pH meter. Buffering capacity -0.01 M hydrochloric acid was added to every sample until pH reduction of two units was achieved.<br><br>STATISTICAL ANALYSIS USED: One-way ANOVA test, Tukey's post hoc test, independent Student's t-test were performed. The level of significance was set at P < 0.05.<br><br>RESULTS: SBM had highest optical density (OD) value and HBM least. PBM had the highest pH and SBM least. PBM had highest B value (Buffering) and HBM least.<br><br>CONCLUSION: Cariogenicity of both HBM and PBM were shown to be just marginal although differing from sucrose.}, }
@article {pmid39796259, year = {2025}, author = {Renye, JA and Chen, CY and Miller, A and Lee, J and Oest, A and Lynn, KJ and Felton, SM and Guragain, M and Tomasula, PM and Berger, BW and Capobianco, J}, title = {Integrating Bacteriocins and Biofilm-Degrading Enzymes to Eliminate L. monocytogenes Persistence.}, journal = {International journal of molecular sciences}, volume = {26}, number = {1}, pages = {}, pmid = {39796259}, issn = {1422-0067}, support = {8072-42000-093-000-D//United States Department of Agriculture/ ; 8072-42000-094-000-D//United States Department of Agriculture/ ; 8072-41000-114-D//United States Department of Agriculture/ ; SCRI 2023-05675//United States Department of Agriculture/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Listeria monocytogenes/drug effects ; *Bacteriocins/pharmacology/metabolism ; Anti-Bacterial Agents/pharmacology ; Streptococcus thermophilus/enzymology ; Listeriosis/drug therapy/microbiology ; }, abstract = {Listeria monocytogenes is a Gram-positive bacterium causing listeriosis, a severe infection responsible for significant morbidity and mortality globally. Its persistence on food processing surfaces via biofilm formation presents a major challenge, as conventional sanitizers and antimicrobials exhibit limited efficacy against biofilm-embedded cells. This study investigates a novel approach combining an engineered polysaccharide-degrading enzyme (CAase) with a bacteriocin (thermophilin 110) produced by Streptococcus thermophilus. Laboratory assays evaluated the effectiveness of this combination in disrupting biofilms and inactivating L. monocytogenes on various surfaces. The results demonstrated that CAase effectively disrupts biofilm structures, while thermophilin 110 significantly reduces bacterial growth and viability. The preliminary trials indicate a dual-action approach offers a potential alternative to conventional treatments, enhancing food safety by effectively controlling Listeria biofilms in food processing environments.}, }
@article {pmid39794652, year = {2025}, author = {Das, T and Das, MC and Das, A and Bhowmik, S and Sandhu, P and Akhter, Y and Bhattacharjee, S and De, UC}, title = {Correction: Modulation of S. aureus and P. aeruginosa biofilm: an in vitro study with new coumarin derivatives.}, journal = {World journal of microbiology &amp; biotechnology}, volume = {41}, number = {2}, pages = {33}, doi = {10.1007/s11274-024-04221-6}, pmid = {39794652}, issn = {1573-0972}, }
@article {pmid39794383, year = {2025}, author = {Khalefa, HS and Arafa, AA and Hamza, D and El-Razik, KAA and Ahmed, Z}, title = {Emerging biofilm formation and disinfectant susceptibility of ESBL-producing Klebsiella pneumoniae.}, journal = {Scientific reports}, volume = {15}, number = {1}, pages = {1599}, pmid = {39794383}, issn = {2045-2322}, mesh = {*Klebsiella pneumoniae/drug effects/isolation &amp; purification ; *Biofilms/drug effects/growth &amp; development ; Animals ; *beta-Lactamases/genetics/metabolism ; *Disinfectants/pharmacology ; Humans ; *Klebsiella Infections/veterinary/microbiology ; *Chickens/microbiology ; Egypt ; Horses ; Microbial Sensitivity Tests ; Anti-Bacterial Agents/pharmacology ; }, abstract = {Klebsiella pneumoniae is an opportunistic pathogen responsible for various infections in humans and animals. It is known for its resistance to multiple antibiotics, particularly through the production of Extended-Spectrum Beta-Lactamases (ESBLs), and its ability to form biofilms that further complicate treatment. This study aimed to isolate and identify K. pneumoniae from animal and environmental samples and assess commercial disinfectants' effectiveness against K. pneumoniae isolates exhibiting ESBL-mediated resistance and biofilm-forming ability in poultry and equine farms in Giza Governorate, Egypt. A total of 320 samples, including nasal swabs from equine (n = 60) and broiler chickens (n = 90), environmental samples (n = 140), and human hand swabs (n = 30), were collected. K. pneumoniae was isolated using lactose broth enrichment and MacConkey agar, with molecular confirmation via PCR targeting the gyrA and magA genes. PCR also identified ESBL genes (blaTEM, blaSHV, blaCTX-M, blaOXA-1) and biofilm genes (luxS, Uge, mrkD). Antimicrobial susceptibility was assessed, and the efficacy of five commercial disinfectants was evaluated by measuring inhibition zones. Klebsiella pneumoniae was isolated from poultry (13.3%), equine (8.3%), wild birds (15%), water (10%), feed (2%), and human hand swabs (6.6%). ESBL and biofilm genes were detected in the majority of the isolates, with significant phenotypic resistance to multiple antibiotics. The disinfectants containing peracetic acid and hydrogen peroxide were the most effective, producing the largest inhibition zones, while disinfectants based on sodium hypochlorite and isopropanol showed lower efficacy. Statistical analysis revealed significant differences in the effectiveness of disinfectants against K. pneumoniae isolates across various sample origins (P < 0.05). The presence of K. pneumoniae in animal and environmental sources, along with the high prevalence of ESBL-mediated resistance and biofilm-associated virulence genes, underscores the zoonotic potential of this pathogen. The study demonstrated that disinfectants containing peracetic acid and hydrogen peroxide are highly effective against ESBL-producing K. pneumoniae. Implementing appropriate biosecurity measures, including the use of effective disinfectants, is essential for controlling the spread of resistant pathogens in farm environments.}, }
@article {pmid39793676, year = {2025}, author = {Ribeiro Lima, FR and Figueiredo, LC and Oliveira Braga, AR and Garcia, MAR and Carvalho, SG and Regasini, LO and Chorilli, M and Sardi, JCO}, title = {Antimicrobial and anti-biofilm activity of a mucoadhesive hydrogel functionalized with aminochalcone on titanium surfaces and in Galleria mellonella model: In vitro and in vivo study.}, journal = {Microbial pathogenesis}, volume = {200}, number = {}, pages = {107286}, doi = {10.1016/j.micpath.2025.107286}, pmid = {39793676}, issn = {1096-1208}, abstract = {Peri-implantitis associated with dental implants shares characteristics with destructive periodontal diseases. Both conditions are multifactorial and strongly correlated with the presence of microorganisms surrounding the prostheses or natural dentition. This study aimed to evaluate the antimicrobial activity and toxicity of a mucoadhesive hydrogel functionalized with aminochalcone (HAM-15) against Aggregatibacter actinomycetemcomitans, Fusobacterium periodonticum, Prevotella intermedia, Porphyromonas gingivalis, Tannerella forsythia, and Candida albicans. Various experiments were conducted to determine the minimum inhibitory concentrations (MIC) and minimum bactericidal/fungicidal concentrations (MBC/MFC), as well as the antibiofilm potential and toxicity in human gingival fibroblasts and a G. mellonella animal model. Infection and treatment studies were also performed in G. mellonella. The results demonstrated that both aminochalcone (AM-15) and the aminochalcone-functionalized hydrogel (HAM-15) exhibited antimicrobial activity, with MICs ranging from 7.8 to 31.2 μg/mL for the tested strains. Treatment with HAM-15 at 300 μg/mL reduced the monospecies biofilm of C. albicans and P. gingivalis by 7 log10 and 6 log10, respectively, and the mixed-species biofilm of these microorganisms by 7 log10 and 8 log10, respectively. Regarding toxicity, HAM-15 showed cytotoxic effects on human gingival fibroblasts at high concentrations, but in the G. mellonella model, survival was 70 % at a dose of 1 mg/mL. Additionally, AM-15, when administered after larval infection, protected 90 % of the animals (p < 0.05). These results suggest that AM-15 is a promising candidate for the prevention and treatment of anaerobic infections and yeasts, demonstrating significant antimicrobial efficacy and an acceptable safety profile in experimental models.}, }
@article {pmid39793452, year = {2025}, author = {Śliwka, P and Moreno, DS and Korzeniowski, P and Milcarz, A and Kuczkowski, M and Kolenda, R and Kozioł, S and Narajczyk, M and Roesler, U and Tomaszewska-Hetman, L and Kuźmińska-Bajor, M}, title = {Avian pathogenic Escherichia coli-targeting phages for biofilm biocontrol in the poultry industry.}, journal = {Veterinary microbiology}, volume = {301}, number = {}, pages = {110363}, doi = {10.1016/j.vetmic.2024.110363}, pmid = {39793452}, issn = {1873-2542}, mesh = {*Biofilms ; Animals ; *Escherichia coli/virology ; *Poultry Diseases/microbiology/prevention &amp; control/virology ; *Poultry/microbiology ; *Escherichia coli Infections/veterinary/microbiology/prevention &amp; control ; Coliphages/physiology/genetics ; Chickens ; Genome, Viral ; Phage Therapy ; }, abstract = {Avian pathogenic Escherichia coli (APEC) is a principal etiologic agent of avian colibacillosis, responsible for significant economic losses in the poultry industry due to high mortality and disease treatment with antibiotics. APEC and its ability to form biofilms on food and processing surfaces contributes to its persistence within farms. Bacteriophages are promising antibacterial agents for combating APEC. This study focused on characterization of the newly isolated phages UPWr_E1, UPWr_E2, and UPWr_E4 as well as the UPWr_E124 phage cocktail containing these three phages. Methods included efficiency of plating assay, transmission electron microscopy, and characterization of their resistance to different pH values and temperatures. Moreover, phage genomes were sequenced, annotated and analyzed, and were compared with previously sequenced E. coli phages. All three phages are virulent and devoid of undesirable genes for therapy. Phage UPWr_E1 belongs to the genus Krischvirus within the order Straboviridae and both UPWr_E2 and UPWr_E4 belong to the genus Tequatrovirus within the subfamily Tevenvirinae, sharing over 95 % nucleotide identity between them. For their use on poultry farms, UPWr_E phages and the UPWr_E124 phage cocktail were tested for their anti-biofilm activity on two E. coli strains - 158B (APEC) and the strong biofilm producer NCTC 17848 - on two abiotic surfaces: a 96-well microplate, a stainless steel surface, and one biotic surface, represented by lettuce leaves. The reduction of biofilm formed by both strains in the 96-well microplate, on the stainless steel and lettuce leaf surface for bacteriophage treatment was very efficient, reducing biofilms by ranges of 50.2-83.6, 58.2-88.4 and 53-99.4 %, respectively. Therefore, we conclude that UPWr_E phages and the UPWr_E124 phage cocktail are promising candidates for APEC biocontrol.}, }
@article {pmid39788184, year = {2025}, author = {LaPointe, G and Wilson, T and Tarrah, A and Gagnon, M and Roy, D}, title = {BIOFILM DAIRY FOODS REVIEW: Microbial Community Tracking from Dairy Farm to Factory: Insights on Biofilm Management for Enhanced Food Safety and Quality.}, journal = {Journal of dairy science}, volume = {}, number = {}, pages = {}, doi = {10.3168/jds.2024-25397}, pmid = {39788184}, issn = {1525-3198}, abstract = {This review aimed to assess the scope of the literature on tracking the microbial community of biofilms, focusing on the dairy farm and processing environments. The majority of studies focused on either production, storage, transport or processing of milk, while 5 combined the investigation of both production and processing facilities. Factors influencing short-term changes in dairy microbiota such as the occurrence of mastitis and season were distinguished from factors revealed through long-term studies, such as feed and weather, rather than the milking equipment. Knowledge gaps were identified in relation to the study design, methods, data analysis and interpretation. The application of DNA sequencing technologies is particularly challenging with respect to samples with low microbial load (milk, swabs). There are few studies on the microbial composition of in situ biofilms, which might require new technologies for detection before sampling. Fundamental studies on the structure of biofilms are needed to identify the on-farm practices impacting the cycle of biofilm development in milking systems.}, }
@article {pmid39787975, year = {2025}, author = {Marasini, S and Dean, SJ and Swift, S and Hussan, JR and Craig, JP}, title = {In vitro anti-biofilm efficacy of therapeutic low dose 265 nm UVC.}, journal = {Journal of photochemistry and photobiology. B, Biology}, volume = {263}, number = {}, pages = {113091}, doi = {10.1016/j.jphotobiol.2024.113091}, pmid = {39787975}, issn = {1873-2682}, mesh = {*Biofilms/drug effects/radiation effects ; *Pseudomonas aeruginosa/physiology/radiation effects/drug effects ; *Ultraviolet Rays ; Microscopy, Confocal ; }, abstract = {PURPOSE: Preclinical studies have confirmed the safety and efficacy of narrowband low-intensity ultraviolet C light (UVC) in managing bacterial corneal infection. To further consolidate these findings, the present study aimed to explore in vitro anti-biofilm efficacy of low-intensity UVC light for its potential use in biofilm-related infections.<br><br>METHODS: Pseudomonas aeruginosa biofilm was grown in chamber well slides for 48&#xa0;h and exposed to one of the following challenges: UVC (265&#xa0;nm wavelength, intensity 1.93&#xa0;mW/cm[2]) for 15&#xa0;s, 30 s, 60 s or 120&#xa0;s duration, 70% propanol (positive control), or no exposure (negative control). Bacterial LIVE/DEAD staining was conducted at 1&#xa0;h, 4&#xa0;h, 6&#xa0;h and 8&#xa0;h after challenge exposures to assess the temporal pattern of biofilm inactivation, and slides were imaged using confocal microscopy. Treatment efficacy was quantified by dead biofilm biomass (volume/area - &#x3bc;m[3]/&#x3bc;m[2]) for different treatment groups at each time point.<br><br>RESULTS: At each time point post-exposure, dead biofilm biomass was consistently higher in the alcohol- and UVC-challenged groups than in the unchallenged control (p&#xa0;<&#xa0;0.05), suggesting a sustained biocidal impact after a given challenge. The quantity of dead biofilm biomass did not differ between UVC groups at any time point (p&#xa0;>&#xa0;0.05). Observed by confocal microscopy, UVC-exposed biofilm demonstrated predominantly intermediate-stage biofilm (i.e., dying state) at 1&#xa0;h, which progressed to dead biofilm by 4&#xa0;h.<br><br>CONCLUSION: Low doses of UVC demonstrated potent anti-biofilm activity, even in exposures as short as 15&#xa0;s, the dose that has previously been deemed to be effective in managing corneal infection in vivo. These data support the potential for this UVC light-based technology to serve as an affordable, convenient, and effective means of treating ocular infections associated with bacterial biofilm.}, }
@article {pmid39787933, year = {2024}, author = {Gulizia, AM and Bell, SC and Kuek, F and Santana, MMF and Edmunds, RC and Yeoh, YK and Sato, Y and Haikola, P and van Herwerden, L and Motti, CA and Bourne, DG and Vamvounis, G}, title = {Biofilm development as a factor driving the degradation of plasticised marine microplastics.}, journal = {Journal of hazardous materials}, volume = {487}, number = {}, pages = {136975}, doi = {10.1016/j.jhazmat.2024.136975}, pmid = {39787933}, issn = {1873-3336}, abstract = {Biodegradation of microplastics facilitated by natural marine biofouling is a promising approach for ocean bioremediation. However, implementation requires a comprehensive understanding of how interactions between the marine microbiome and dominant microplastic debris types (e.g., polymer and additive combinations) can influence biofilm development and drive biodegradation. To investigate this, polystyrene (PS) and polyvinyl chloride (PVC) microplastics (< 200 µm in diameter) were prepared either without any additives (i.e., virgin) or containing 15 wt% of the plasticisers diethylhexyl phthalate (DEHP) or bisphenol A (BPA). Each polymer-plasticiser microplastic combination was exposed to environmentally relevant conditions in a simulated seawater mesocosm representative of tropical reef waters over a 21-day period to allow for natural biofilm development. Following this, microplastic degradation and the colonising bacterial biofilm was assessed as a function of time, polymer and plasticiser type using infrared, thermal, gel permeation and surface characterisation techniques, as well as 16S ribosomal RNA bacterial gene sequencing, respectively. Together, these analyses revealed time-, polymer- and plasticiser-dependent degradation, particularly of the PS-BPA microplastics. Degradation of the PS-BPA microplastics also coincided with changes in bacterial community composition and an increased total relative abundance of putative biodegradative bacteria. These findings indicate that the metabolic potential and biodegradative capability of the colonising marine biofilm can be significantly impacted by the chemical properties of the microplastic substrate, even within short timeframes.}, }
@article {pmid39787875, year = {2025}, author = {Coutaud, M and Viers, J and Rols, JL and Pokrovsky, OS}, title = {Copper and zinc isotope fractionation during phototrophic biofilm growth.}, journal = {The Science of the total environment}, volume = {960}, number = {}, pages = {178371}, doi = {10.1016/j.scitotenv.2025.178371}, pmid = {39787875}, issn = {1879-1026}, mesh = {*Biofilms ; *Copper ; *Zinc/metabolism ; *Water Pollutants, Chemical ; Cyanobacteria/metabolism/physiology ; Zinc Isotopes ; Chemical Fractionation ; Phototrophic Processes ; Chlorophyta/metabolism ; Diatoms/metabolism/physiology ; }, abstract = {Copper (Cu) and zinc (Zn) are two trace metals that exhibit both limiting and toxic effects on aquatic microorganisms. However, in contrast to good knowledge of these metal interactions with individual microbial cultures, the biofilm, complex natural consortium of microorganisms, remains poorly understood with respect to its control on Cu and Zn in the aquatic environments. Towards constraining the magnitude and mechanisms of Cu and Zn isotope fractionation in the presence of phototrophic biofilms composed of different proportion of diatoms, green algae and cyanobacteria, we studied long-term growth in a rotating annular bioreactor and quantified the uptake of metals and their isotope fractionation at environmentally-relevant Cu and Zn concentrations. An enrichment of the biofilm in heavy Cu isotope at the beginning of growth suggests the dominance of adsorption processes, followed by intracellular uptake leading to progressive enrichment in light isotope and an excretion of heavy isotope, likely linked to Cu(II) reduction. In the case of Zn, we evidenced only weak isotope fractionation which implies the presence of heavier isotope adsorption (notably in the case of cyanobacteria-dominated biofilm) followed by intracellular incorporation of lighter isotopes. The microbial community plays important role in overall magnitude and even direction of fractionation, suggesting sizable complexity of the processes controlling metal isotope fractionation during phototrophic biofilm growth. However, Cu and Zn isotopes during long-term metal accumulation in riverine biofilm can be used for monitoring the source of environmental pollution in aquatic systems, provided that variations within different sources exceed the natural isotopic fractionation between the biofilm and aqueous solution.}, }
@article {pmid39781092, year = {2024}, author = {Adeboye, A and Onyeaka, H and Al-Sharify, Z and Nnaji, N}, title = {Understanding the Influence of Rheology on Biofilm Adhesion and Implication for Food Safety.}, journal = {International journal of food science}, volume = {2024}, number = {}, pages = {2208472}, pmid = {39781092}, issn = {2314-5765}, abstract = {Understanding biofilm rheology is crucial for industrial and domestic food safety practices. This comprehensive review addresses the knowledge gap on the rheology of biofilm. Specifically, the review explores the influence of fluid flow, shear stress, and substrate properties on the initiation, structure, and functionality of biofilms, as essential implications for food safety. The viscosity and shear-thinning characteristics of non-Newtonian fluids may impact the attachment and detachment dynamics of biofilms, influencing their stability and resilience under different flow conditions. The discussion spans multiple facets, including the role of extracellular polymeric substances (EPSs) in biofilm formation, the impact of rheological attributes of biofilm on their adhesion to surfaces, and the influence of shear forces between biofilms and substrate's surface characteristics on biofilm stability. Analytical techniques, encompassing rheometry, microscopy, and molecular biology approaches, are scrutinized for their contributions to understanding these interactions. The paper delves into the implications for the food industry, highlighting potential risks associated with biofilm formation and proposing strategies for effective control and prevention. Future research directions and the integration of rheological considerations into food safety regulations are underscored as pivotal steps in mitigating biofilm-related risks. The synthesis of microbiology, materials science, and engineering perspectives offers a multidimensional exploration of rheology-biofilm interactions, laying the groundwork for informed interventions in diverse industrial settings.}, }
@article {pmid39779734, year = {2025}, author = {Wardell, SJT and Yung, DBY and Gupta, A and Bostina, M and Overhage, J and Hancock, REW and Pletzer, D}, title = {DJK-5, an anti-biofilm peptide, increases Staphylococcus aureus sensitivity to colistin killing in co-biofilms with Pseudomonas aeruginosa.}, journal = {NPJ biofilms and microbiomes}, volume = {11}, number = {1}, pages = {8}, pmid = {39779734}, issn = {2055-5008}, mesh = {*Biofilms/drug effects ; *Colistin/pharmacology ; *Pseudomonas aeruginosa/drug effects ; Animals ; *Anti-Bacterial Agents/pharmacology ; *Drug Synergism ; Mice ; *Staphylococcus aureus/drug effects ; *Staphylococcal Infections/drug therapy/microbiology ; *Microbial Sensitivity Tests ; Methicillin-Resistant Staphylococcus aureus/drug effects ; Humans ; Pseudomonas Infections/drug therapy/microbiology ; Daptomycin/pharmacology ; Disease Models, Animal ; Oligopeptides ; }, abstract = {Chronic infections represent a significant global health and economic challenge. Biofilms, which are bacterial communities encased in an extracellular polysaccharide matrix, contribute to approximately 80% of these infections. In particular, pathogens such as Pseudomonas aeruginosa and Staphylococcus aureus are frequently co-isolated from the sputum of patients with cystic fibrosis and are commonly found in chronic wound infections. Within biofilms, bacteria demonstrate a remarkable increase in resistance and tolerance to antimicrobial treatment. We investigated the efficacy of combining the last-line antibiotic colistin with a membrane- and stringent stress response-targeting anti-biofilm peptide DJK-5 against co-biofilms comprised of multidrug-resistant P. aeruginosa and methicillin-resistant S. aureus (MRSA). Colistin lacks canonical activity against S. aureus. However, our study revealed that under co-biofilm conditions, the antibiofilm peptide DJK-5 synergized with colistin against S. aureus. Similar enhancement was observed when daptomycin, a cyclic lipopeptide against Gram-positive bacteria, was combined with DJK-5, resulting in increased activity against P. aeruginosa. The combinatorial treatment induced morphological changes in both P. aeruginosa and S. aureus cell shape and size within co-biofilms. Importantly, our findings also demonstrate synergistic activity against both P. aeruginosa and S. aureus in a murine subcutaneous biofilm-like abscess model. In conclusion, combinatorial treatments with colistin or daptomycin and the anti-biofilm peptide DJK-5 show significant potential for targeting co-biofilm infections. These findings offer promising avenues for developing new therapeutic approaches to combat complex chronic infections.}, }
@article {pmid39778756, year = {2025}, author = {Zehra, M and Asghar, S and Ilyas, R and Usmani, Y and Khan, RMA and Mirani, ZA and Ahmed, A}, title = {Relationship of biofilm formation with antibiotic resistance, virulence determinants and genetic diversity in clinically isolated Acinetobacter baumannii strains in Karachi, Pakistan.}, journal = {Microbial pathogenesis}, volume = {200}, number = {}, pages = {107283}, doi = {10.1016/j.micpath.2025.107283}, pmid = {39778756}, issn = {1096-1208}, abstract = {Multi-drug resistant (MDR) Acinetobacter baumannii causes nosocomial infections due to a plethora of virulence determinants like biofilm formation which are pivotal to its survival and pathogenicity. Hence, investigation of these mechanisms in currently circulating strains is required for effective infection control and drug development. This study investigates the prevalence of antibiotic resistance and virulence factors and their relationship with biofilm formation in Acinetobacter baumannii strains in Karachi, Pakistan. Enterobacterial Repetitive Intergenic Consensus Polymerase Chain Reaction (ERIC PCR) was used for observing genetic variations. The results revealed that 100 % A. baumannii strains were MDR and 74.4 % had multiple antibiotic resistance index (MARi) of 0.875-1. There were 27 biofilm forming strains with a moderate correlation between biofilm formation and MARi. A high prevalence of abaI (86.04 %), bfmR (95.3 %), bfmS (97.6 %), csuE (90.69 %), ompA (74.4 %), and pgaA virulence genes (95.3 %) and resistance genes adeF (53.4 %), adeJ (74.4 %), ampC (51.1 %), tem-1 (51.1 %), and vim (65.1 %)) were observed in these strains. ERIC PCR revealed that 5 of 22 genetic types had strong biofilm form strains with similar virulence genes profiles. Conclusively, the study shows escalated resistance and virulence in clinical strains which warrants consistent epidemiological studies to prevent infections spread and future outbreaks.}, }
@article {pmid39777967, year = {2025}, author = {Mohammed Aggad, FZ and Ilias, F and Elghali, F and Mrabet, R and El Haci, IA and Aifa, S and Mnif, S}, title = {Evaluation of Antibacterial Activity in Some Algerian Essential Oils and Selection of Thymus vulgaris as a Potential Biofilm and Quorum Sensing Inhibitor Against Pseudomonas aeruginosa.}, journal = {Chemistry &amp; biodiversity}, volume = {}, number = {}, pages = {e202402691}, doi = {10.1002/cbdv.202402691}, pmid = {39777967}, issn = {1612-1880}, abstract = {Biofilm formation and virulence factor production by Pseudomonas aeruginosa are identified as the main mechanisms of its antibiotic resistance and pathogenicity. In this context, the study of the chemical composition of three Algerian essential oils (EOs) and the screening of their antibacterial, antibiofilm, and virulence factor inhibitory activities enabled us to select the thyme EO as the best oil to control the P. aeruginosa strain isolated from hospital environments. This EO, composed essentially of thymol (55.82%) associated with carvacrol, had an anti-adhesive activity of 69.8% at a concentration of 5 µL/mL and a biofilm eradication activity of 74.86% at a concentration of 2.5 µL/mL. In addition, this EO was able to inhibit P. aeruginosa twitching motility by 100% at a concentration of 2.5 µL/mL. Pyocyanin was inhibited by 99.33% at a thyme EO concentration of 1.25 µL/mL. Rhamnolipids were significantly inhibited by 63.33% in the presence of thyme EO at a concentration of 1.25 µL/mL after 24 h of incubation. Molecular docking showed that carvacrol and thymol can bind to the three quorum sensing receptors in P. aeruginosa, RhlR, LasR, and PqsR, with good affinities, which can inhibit or modulate biofilm formation and the production of certain virulence factors.}, }
@article {pmid39777149, year = {2024}, author = {Yin, L and Guo, Y and Xv, X and Dai, Y and Li, L and Sun, F and Lv, X and Shu, G and Liang, X and He, C and Xu, Z and Ouyang, P}, title = {Cinnamaldehyde nanoemulsion decorated with rhamnolipid for inhibition of methicillin-resistant Staphylococcus aureus biofilm formation: in vitro and in vivo assessment.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1514659}, pmid = {39777149}, issn = {1664-302X}, abstract = {BACKGROUND: Staphylococcus aureus (S. aureus) biofilm associated infections are prevalent and persistent, posing a serious threat to human health and causing significant economic losses in animal husbandry. Nanoemulsions demonstrate significant potential in the treatment of bacterial biofilm associated infections due to their unique physical, chemical and biological properties. In this study, a novel cinnamaldehyde nanoemulsion with the ability to penetrate biofilm structures and eliminate biofilms was developed.<br><br>METHODS: The formulation of cinnamaldehyde nanoemulsion (Cin-NE) combined with rhamnolipid (RHL) was developed by self-assembly, and the efficacies of this formulation in inhibiting S. aureus biofilm associated infections were assessed through in vitro assays and in vivo experiments by a mouse skin wound healing model.<br><br>RESULTS: The particle size of the selected Cin-NE formulation was 13.66&#x202f;&#xb1;&#x202f;0.08&#x202f;nm, and the Cin-RHL-NE formulation was 20.45&#x202f;&#xb1;&#x202f;0.25&#x202f;nm. The selected Cin-RHL-NE formulation was stable at 4, 25, and 37&#xb0;C. Furthermore, the Minimum Inhibitory Concentration (MIC) value of Cin-RHL-NE against MRSA was two-fold lower than drug solution. Confocal laser scanning microscopy (CLSM) revealed the superior efficacy of Cin-RHL-NE in eradicating MRSA biofilms while maintaining the Cin's inherent functional properties. The efficacy of Cin-RHL-NE in the mouse skin wound healing model was superior to other formulation.<br><br>CONCLUSION: These findings highlight the potential of the formulation Cin-RHL-NE for eradicating biofilms, and effective in treating notoriously persistent bacterial infections. The Cin-RHL-NE can used as a dosage form of Cin application to bacterial biofilm associated infections.}, }
@article {pmid39773469, year = {2025}, author = {Wang, D and Zeng, N and Li, C and Li, C and Wang, Y and Chen, B and Long, J and Zhang, N and Li, B}, title = {Integrative analysis of transcriptome and metabolome profiling uncovers underlying mechanisms of the enhancement of the synthesis of biofilm in Sporobolomyces pararoseus NGR under acidic conditions.}, journal = {Microbial cell factories}, volume = {24}, number = {1}, pages = {9}, pmid = {39773469}, issn = {1475-2859}, support = {31271818//National Natural Science Foundation of China/ ; 2023-01//International Cooperation Project of Universities in Liaoning Province/ ; 2022030673-JH5/104//Liaoning Province Rural Science and Technology Special Action Project/ ; 22-319-2-13//Shenyang Science and Technology Project/ ; CSC202208850002//China Scholarship Council/ ; }, mesh = {*Biofilms ; *Transcriptome ; *Metabolome ; Hydrogen-Ion Concentration ; Gene Expression Profiling ; Burkholderiaceae/metabolism/genetics ; }, abstract = {BACKGROUND: Sporobolomyces pararoseus is a well-studied oleaginous red yeast that can synthesize a variety of high value-added bioactive compounds. Biofilm is one of the important biological barriers for microbial cells to resist environmental stresses and maintain stable fermentation process. Here, the effect of acidic conditions on the biosynthesis of biofilms in S. pararoseus NGR was investigated through the combination of morphology, biochemistry, and multi-omics approaches.<br><br>RESULTS: The results showed that the acidic environment was the key factor to trigger the biofilm formation of S. pararoseus NGR. When S. pararoseus NGR was cultured under pH 4.7, the colony morphology was wrinkled, the cells were wrapped by a large amount of extracellular matrix, and the hydrophobicity and anti-oxidative stress ability were significantly improved, and the yield of intracellular carotenoids was significantly increased. Transcriptome and metabolome profiling indicated that carbohydrate metabolism, amino acid metabolism, lipid metabolism, and nucleic acid metabolism in S. pararoseus NGR cells were significantly enriched in biofilm cells under pH 4.7 culture conditions, including 56 differentially expressed genes and 341 differential metabolites.<br><br>CONCLUSIONS: These differential genes and metabolites may play an important role in the formation of biofilms by S. pararoseus NGR in response to acidic stress. The results will provide strategies for the development and utilization of beneficial microbial biofilms, and provide theoretical support for the industrial fermentation production of microorganisms to improve their resistance and maintain stable growth.}, }
@article {pmid39772813, year = {2024}, author = {Maciel, JG and Gomes, ACG and Sugio, CY and Garcia, AA and Zani, IF and Fernandes, MH and Soares, S and Neppelenbroek, KH}, title = {Denture biofilm increases respiratory diseases in the elderly. A mini-review.}, journal = {American journal of dentistry}, volume = {37}, number = {6}, pages = {288-292}, pmid = {39772813}, issn = {0894-8275}, mesh = {*Biofilms ; Humans ; Aged ; Dentures/microbiology ; Acrylic Resins ; Respiratory Tract Infections/microbiology ; Respiratory Tract Diseases/microbiology ; }, abstract = {PURPOSE: This mini-review discusses the clinical implication of respiratory pathogens in the biofilm on acrylic resin removable dentures in the elderly.<br><br>METHODS: A search was conducted using the keywords: "dentures", " acrylic resin", "biofilm", "pneumonia", "elderly", "respiratory pathogens", and "respiratory diseases" in databases PubMed/Medline, Lilacs, SciELO and textbooks between 1999 and 2024.<br><br>RESULTS: The elderly are more susceptible to chronic diseases and/or life-threatening infections because of senescence itself and functional and degenerative alterations. Respiratory tract diseases (such as pneumonia) are of greater concern in the elderly because they have been associated with the aspiration of food and oral pathogens and with reflux. This relationship is more aggravating in the presence of removable dentures, common in the elderly after the sixth decade of life, since denture biofilm is a reservoir of respiratory pathogens. Lack of manual dexterity and visual acuity negatively interfere with denture cleaning and favor pathogenic denture biofilm maturation. Reduced salivary flow, a more acidic pH, and a reduced cough reflex associated with poor denture cleaning increase the potential of denture biofilm infections and aspiration pneumonia, which is related to a high mortality rate in the elderly. To prevent respiratory diseases in this population, measures to control denture biofilm should be adopted, such as the superficial or intrinsic modification of the acrylic resin denture bases and the use of effective methods of denture cleaning.<br><br>CLINICAL SIGNIFICANCE: Respiratory pathogens colonizing denture biofilm can be aspirated into the respiratory tract, increasing the risk of respiratory infections, especially in the elderly. The knowledge of health professionals on methods of biofilm control can prevent respiratory diseases in elderly denture wearers.}, }
@article {pmid39772812, year = {2024}, author = {Shamieh, S and Ribeiro, AA and Sulaiman, T and Swift, EJ and Vasconcellos, AB}, title = {Biofilm attachment and mineralizing potential of contemporary restorative materials.}, journal = {American journal of dentistry}, volume = {37}, number = {6}, pages = {279-287}, pmid = {39772812}, issn = {0894-8275}, mesh = {*Biofilms ; *Composite Resins/chemistry ; Humans ; *Dental Restoration, Permanent/methods ; *Resin Cements/chemistry ; Dental Materials/chemistry ; Materials Testing ; Dentin/microbiology ; X-Ray Microtomography ; In Vitro Techniques ; Molar ; }, abstract = {PURPOSE: To evaluate and compare: (1) the effect of the bacterial biofilm on the dentin mineral density at the restoration-tooth interface and (2) the mineralization potential of three resin-based restorative materials (RBRM).<br><br>METHODS: 16 extracted human molars free of caries and cracks were collected and stored for disinfection. Each tooth received two standardized Class II preparations with the cervical margin placed in dentin. Teeth were secured into a dentiform with adjacent natural teeth to ensure interproximal contact. All tooth preparations were hybridized using a three-step etch-and-rinse adhesive system (OptiBond FL) and assigned randomly to three experimental groups according to the RBRM (n= 8): Group A - a nanofill resin composite (Filtek Supreme Ultra); Group B - a high-viscosity bulk-fill resin composite (Tetric Powerfill); Group C - a low-viscosity bulk-fill resin composite (SureFil SDR flow+ bulk-fill); and a positive control: Group D - bioactive resin composite (Activa Bioactive-Restorative). All materials were used according to manufacturers' instructions. All specimens were subjected to two distinct challenges: first, thermomechanical cycling was performed within 24 hours of restoring the specimens to simulate 1 year of masticatory function. Subsequently, the specimens were stored for 18 days in a laboratory biofilm model to promote biofilm formation and to mimic the effects of tooth demineralization. Two sessions of micro-CT imaging were conducted: the first immediately after the thermomechanical cycling and the second post-exposure to the biofilm model. All data on mineral profile measurements reconstructed in the Perkin-Elmer Quantum GX-II CT were transferred to Image J software for analysis and interpretation. The ANOVA test (P< 0.05) was used to analyze the mineral density values and mean mineral loss values for each group.<br><br>RESULTS: No statistically significant difference in mean mineral loss value (mean &#x394;Z) was found between the groups (P= 0.209). Regardless, increased mean &#x394;Z variation was found between SureFil SDR flow+ (-56.95) and the remaining groups, Filtek Supreme Ultra, Tetric Powerfill and Activa Bioactive (-1.17, -1.41, and -7.97, respectively), showing, within the limits of the present laboratory study, the remineralization potential of SureFil SDR flow+. All tested RBRM demonstrated some remineralization capacity under caries risk conditions.<br><br>CLINICAL SIGNIFICANCE: The mineralization potential of some resin-based composites under caries-risk conditions can represent a paradigm shift in restorative material selection for moderate-to-high-risk patients.}, }
@article {pmid39770726, year = {2024}, author = {Mendes, MB and Vidigal, PMP and Soto Lopez, ME and Hungaro, HM}, title = {Combined Effects of the Pijolavirus UFJF_PfSW6 Phage and Sodium Hypochlorite for Reducing Pseudomonas fluorescens Biofilm.}, journal = {Microorganisms}, volume = {12}, number = {12}, pages = {}, pmid = {39770726}, issn = {2076-2607}, support = {Inovaleite Group and Instituto Sua Ci&#xea;ncia (ISC)//MilkFund/ ; CAG 00146-22//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado de Minas Gerais (FAPEMIG)/ ; 200773/2024-0//Conselho Nacional de Desenvolvimento Cient&#xed;fico e Tecnol&#xf3;gico (CNPq)/ ; Vicerrectoria de Investigaci&#xf3;n y Extensi&#xf3;n and project entitled BPIN 2020000100697, funden By MinCiencias - Colombia//University of C&#xf3;rdoba/ ; }, abstract = {Pseudomonas are significant spoilage bacteria in raw milk and dairy products, primarily due to their ability to form biofilms and resist disinfection. This study explored the effects of the UFJF_PfSW6 phage combined with sodium hypochlorite in reducing Pseudomonas fluorescens biofilms on stainless steel at various temperatures and ages. Biofilms were formed using P. fluorescens UFV 041 in UHT milk, incubated at 4 °C and 30 °C for 2 and 7 days. Two lytic phages were compared, with UFJF_PfSW6 showing superior activity, reducing cell counts by 0.8 to 2.0 logs CFU/cm[2] depending on conditions. Increasing the contact time of the UFJF_PfSW6 phage from 4 to 8 h did not significantly affect the reduction in mature biofilms. The individual treatments of the phage and sodium hypochlorite (100 mg/L) reduced bacterial counts by 0.9 and 0.6 log CFU/cm[2] at 30 °C, and 1.3 and 1.2 log CFU/cm[2] at 4 °C, respectively. However, their sequential application achieved greater reductions, reaching 1.3 and 1.8 log CFU/cm[2] for biofilms formed at 30 °C and 4 °C, respectively. These findings suggest a promising strategy for controlling P. fluorescens in the food industry. Our findings suggest that the UFJF_PfSW6 phage combined with chlorine improves the removal of P. fluorescens biofilms.}, }
@article {pmid39770699, year = {2024}, author = {Horgan, C and Baccari, C and O'Driscoll, M and Lindow, SE and O'Sullivan, TP}, title = {BDSF Analogues Inhibit Quorum Sensing-Regulated Biofilm Production in Xylella fastidiosa.}, journal = {Microorganisms}, volume = {12}, number = {12}, pages = {}, pmid = {39770699}, issn = {2076-2607}, support = {GOIPG/2017/1111//Irish Research Council/ ; GOIPG/2021/227//Irish Research Council/ ; 21/RI/9705/SFI_/Science Foundation Ireland/Ireland ; }, abstract = {Xylella fastidiosa is an aerobic, Gram-negative bacterium that is responsible for many plant diseases. The bacterium is the causal agent of Pierce's disease in grapes and is also responsible for citrus variegated chlorosis, peach phony disease, olive quick decline syndrome and leaf scorches of various species. The production of biofilm is intrinsically linked with persistence and transmission in X. fastidiosa. Biofilm formation is regulated by members of the Diffusible Signal Factor (DSF) quorum sensing signalling family which are comprised of a series of long chain cis-unsaturated fatty acids. This article describes the evaluation of a library of N-acyl sulfonamide bioisosteric analogues of BDSF, XfDSF1 and XfDSF2 for their ability to control biofilm production in X. fastidiosa. The compounds were screened against both the wild-type strain Temecula and an rpfF* mutant which can perceive but not produce XfDSF. Planktonic cell abundance was measured via OD600 while standard crystal violet assays were used to determine biofilm biomass. Several compounds were found to be effective biofilm inhibitors depending on the nature of the sulfonamide substituent. The findings reported here may provide future opportunities for biocontrol of this important plant pathogen.}, }
@article {pmid39770681, year = {2024}, author = {Niu, B and Sun, Y and Niu, Y and Qiao, S}, title = {Ultrasound Treatment Combined with Rhamnolipids for Eliminating the Biofilm of Bacillus cereus.}, journal = {Microorganisms}, volume = {12}, number = {12}, pages = {}, pmid = {39770681}, issn = {2076-2607}, support = {No. NL2022013//Henan University of Technology/ ; No. 32100041//the National Natural Science Foundation of China/ ; No. 21420188//the Cultivation Programme for Young Backbone Teachers in Henan University of Technology/ ; No. 2020BS067//Henan University of Technology/ ; No. 231100110300//the Major Science and Technology Project of Henan/ ; }, abstract = {Biofilm formation by Bacillus cereus is a major cause of secondary food contamination, leading to significant economic losses. While rhamnolipids (RLs) have shown effectiveness against Bacillus cereus, their ability to remove biofilms is limited when used alone. Ultrasound (US) is a non-thermal sterilization technique that has been found to enhance the delivery of antimicrobial agents, but it is not highly effective on its own. In this study, we explored the synergistic effects of combining RLs with US for biofilm removal. The minimum biofilm inhibitory concentration (MBIC) of RLs was determined to be 32.0 mg/L. Using a concentration of 256.0 mg/L, RLs alone achieved a biofilm removal rate of 63.18%. However, when 32.0 mg/L RLs were combined with 20 min of US treatment, the removal rate increased to 62.54%. The highest biofilm removal rate of 78.67% was observed with 256.0 mg/L RLs and 60 min of US exposure. Scanning electron microscopy analysis showed that this combined treatment significantly disrupted the biofilm structure, causing bacterial deformation and the removal of extracellular polymeric substances. This synergistic approach not only inhibited bacterial metabolic activity, aggregation, and adhesion but also reduced early biofilm formation and decreased levels of extracellular polysaccharides and proteins. Furthermore, US treatment improved biofilm permeability, allowing better penetration of RLs and interaction with bacterial DNA, ultimately inhibiting DNA synthesis and secretion. The combination of RLs and US demonstrated superior biofilm removal efficacy, reduced the necessary concentration of RLs, and offers a promising strategy for controlling biofilm formation in the food industry.}, }
@article {pmid39770562, year = {2024}, author = {Tang, D and Liu, Y and Yao, H and Lin, Y and Xi, Y and Li, M and Mao, A}, title = {Transcriptome Analysis Reveals the Mechanism of Y0-C10-HSL on Biofilm Formation and Motility of Pseudomonas aeruginosa.}, journal = {Pharmaceuticals (Basel, Switzerland)}, volume = {17}, number = {12}, pages = {}, pmid = {39770562}, issn = {1424-8247}, support = {12065001//the Regional Fund of the National Natural Science Foundation of China/ ; 32160025//the Regional Fund of the National Natural Science Foundation of China/ ; 20JR10RA224//the Natural Science Foundation of Gansu Province/ ; }, abstract = {Background:Pseudomonas aeruginosa (P. aeruginosa) is a type of pathogen that takes advantage of opportunities to infect and form biofilm during infection. Inhibiting biofilm formation is a promising approach for the treatment of biofilm-related infections. Methods: Here, Y0-C10-HSL (N-cyclopentyl-n-decanamide) was designed, synthesized, and tested for its effect on biofilm formation, motility, and the Caenorhabditis elegans (C. elegans) survival assay. In addition, the molecular mechanism of Y0-C10-HSL on P. aeruginosa biofilm formation was explored using transcriptome analysis. Results: At a concentration of 200 μmol/L Y0-C10-HSL, biofilm and exopolysaccharides were decreased by 38.5% and 29.3%, respectively; Y0-C10-HSL effectively dispersed the pre-formed biofilm and inhibited the motility ability of P. aeruginosa; and the C. elegans survival assay showed that Y0-C10-HSL was safe and provided protection to C. elegans against P. aeruginosa infection (the survival rates of C. elegans were higher than 74% and increased by 39%, 35.1%, and 47.5%, respectively, when treated with 200 μmol/L Y0-C10-HSL at 24, 48, and 80 h). Transcriptome analysis showed that 585 differentially expressed genes (DEGs) were found after treatment with 200 μmol/L Y0-C10-HSL, including 254 up-regulated DEGs and 331 down-regulated DEGs. The genes involved in the quorum sensing system and biofilm formation were down-regulated. Conclusions: Y0-C10-HSL inhibited the biofilm formation and dispersed the pre-formed biofilm of P. aeruginosa through down-regulated genes related to quorum sensing pathways and biofilm formation. These findings provide a theoretical foundation for the treatment and prevention of antibiotic resistance in clinical and environmental microorganisms such as P. aeruginosa.}, }
@article {pmid39770514, year = {2024}, author = {Geremia, N and Giovagnorio, F and Colpani, A and De Vito, A and Botan, A and Stroffolini, G and Toc, DA and Zerbato, V and Principe, L and Madeddu, G and Luzzati, R and Parisi, SG and Di Bella, S}, title = {Fluoroquinolones and Biofilm: A Narrative Review.}, journal = {Pharmaceuticals (Basel, Switzerland)}, volume = {17}, number = {12}, pages = {}, pmid = {39770514}, issn = {1424-8247}, abstract = {Background: Biofilm-associated infections frequently span multiple body sites and represent a significant clinical challenge, often requiring a multidisciplinary approach involving surgery and antimicrobial therapy. These infections are commonly healthcare-associated and frequently related to internal or external medical devices. The formation of biofilms complicates treatment, as they create environments that are difficult for most antimicrobial agents to penetrate. Fluoroquinolones play a critical role in the eradication of biofilm-related infections. Numerous studies have investigated the synergistic potential of combining fluoroquinolones with other chemical agents to augment their efficacy while minimizing potential toxicity. Comparative research suggests that the antibiofilm activity of fluoroquinolones is superior to that of beta-lactams and glycopeptides. However, their activity remains less effective than that of minocycline and fosfomycin. Noteworthy combinations include fluoroquinolones with fosfomycin and aminoglycosides for enhanced activity against Gram-negative organisms and fluoroquinolones with minocycline and rifampin for more effective treatment of Gram-positive infections. Despite the limitations of fluoroquinolones due to the intrinsic characteristics of this antibiotic, they remain fundamental in this setting thanks to their bioavailability and synergisms with other drugs. Methods: A comprehensive literature search was conducted using online databases (PubMed/MEDLINE/Google Scholar) and books written by experts in microbiology and infectious diseases to identify relevant studies on fluoroquinolones and biofilm. Results: This review critically assesses the role of fluoroquinolones in managing biofilm-associated infections in various clinical settings while also exploring the potential benefits of combination therapy with these antibiotics. Conclusions: The literature predominantly consists of in vitro studies, with limited in vivo investigations. Although real world data are scarce, they are in accordance with fluoroquinolones' effectiveness in managing early biofilm-associated infections. Also, future perspectives of newer treatment options to be placed alongside fluoroquinolones are discussed. This review underscores the role of fluoroquinolones in the setting of biofilm-associated infections, providing a comprehensive guide for physicians regarding the best use of this class of antibiotics while highlighting the existing critical issues.}, }
@article {pmid39770495, year = {2024}, author = {Kabotso, DEK and Neglo, D and Gaba, SE and Danyo, EK and Dayie, AD and Asantewaa, AA and Kotey, FCN and Dayie, NTKD}, title = {In Vitro Evaluation of Rosemary Essential Oil: GC-MS Profiling, Antibacterial Synergy, and Biofilm Inhibition.}, journal = {Pharmaceuticals (Basel, Switzerland)}, volume = {17}, number = {12}, pages = {}, pmid = {39770495}, issn = {1424-8247}, support = {RZ07//The Fleming Fund/ ; }, abstract = {Background: Antimicrobial resistance (AMR) has become precarious, warranting investments in antimicrobial discovery. Aim: To investigate the antibacterial activity of rosemary essential oil (REO), alone and in combination with selected conventional antibiotics. Methods: REO was subjected to antimicrobial susceptibility testing (including minimum bactericidal concentration (MBC) and minimum inhibitory concentration (MIC) determination) and investigation of anti-pre-biofilm and antibiofilm activities. Results: The phytochemical composition of the REO was eucalyptol (42.68%), bornanone (33.20%), endo-borneol (9.37%), α-terpeneol (7.95%), linalool (2.10%), bornyl acetate (1.81%), caryophyllene (1.09%), 4-terpeneol (0.94%), and anethole (0.87%). The antibacterial inhibition zones generally increased with increasing REO concentration (i.e., 10, 20, 50, 100, and 200 mg/mL). The MIC and MBC ranges of REO for all bacteria were 3.13-6.25 mg/mL and 3.12-12.5 mg/mL, respectively. The MICs (in µg/mL) of ciprofloxacin, chloramphenicol, streptomycin, tetracycline, and ampicillin, respectively, were Escherichia coli (0.98, 3.92, 1.96, 7.81, and 250), Klebsiella pneumoniae (1.25, 7.81, 125, 7.81, and 1000), MRSA (62.5, 7.81, 3.91, 7.81, and 250), Streptococcus mutans and Bacillus subtilis (125, 15.68, 250, 31.25, and 1000), Pseudomonas aeruginosa (125, 31.25, 500, 31.25, and 1000), and Salmonella Typhi (0.98, 15.68, 125, 1.96, and 1000). The MBC-MIC ratios of REO against all bacteria were in the range 1-2, indicating bactericidal effects. Mainly synergy (FICI = 0.16-0.37) was observed between REO and the conventional antibiotics. The IC50 values (in µg/mL) of REO against the bacteria, pre-biofilm vs. biofilm formation, were E. coli (1342.00 vs. 4.00), K. pneumoniae (106.00 vs. 3.00), MRSA (134.00 vs. 6.00), S. mutans (7259.00 vs. 7.00), B. subtilis (120.00 vs. 7.00), P. aeruginosa (4989.00 vs. 7.00), and S. Typhi (10.00 vs. 2.00). Conclusions: Rosemary essential oil had significant bactericidal effects on the bacteria tested, and its MIC and MBC values were low. Overall, it was synergistic with known conventional antibiotics and, thus, has encouraging prospects in combination therapy involving conventional antibiotics, even in the treatment of infections with multidrug-resistant bacteria, including biofilm-forming ones.}, }
@article {pmid39770454, year = {2024}, author = {Atazhanova, GA and Levaya, YK and Badekova, KZ and Ishmuratova, MY and Smagulov, MK and Ospanova, ZO and Smagulova, EM}, title = {Inhibition of the Biofilm Formation of Plant Streptococcus mutans.}, journal = {Pharmaceuticals (Basel, Switzerland)}, volume = {17}, number = {12}, pages = {}, pmid = {39770454}, issn = {1424-8247}, support = {&#x410;&#x420;23488250//MINISTRY OF SCIENCE AND HIGHER EDUCATION OF REPUBLIC OF KAZAKHSTAN/ ; }, abstract = {This review is devoted to a systematic analysis of studies aimed at investigating plant extracts, essential oils and phytochemical compounds capable of inhibiting Streptococcus mutans biofilm formation. This paper investigates the effect of extracts, essential oils and individual plant compounds on inhibiting the biofilm formation of Streptococcus mutans, one of the major pathogens responsible for the development of dental caries. Using cultural microbiology and molecular biology techniques, the authors describe the mechanisms by which plant samples reduce Streptococcus mutans adhesion and growth. The results show that several plant components have antibacterial properties, contributing to the reduction of Streptococcus mutans colony numbers and inhibiting the synthesis of extract-exopolysaccharide matrices required for biofilm formation. This work highlights the potential of botanicals in inhibiting Streptococcus mutans biofilm formation, which can be applied as natural antimicrobial agents in the prevention and treatment of dental diseases. Views on the use of these plant extracts and their components in dental preparations such as toothpastes, rinses and gels aimed at preventing dental caries are evaluated. The review shows the relevance of the research to optimizing the use of plant extracts, essential oils, individual compounds and their active actions in the control of Streptococcus mutans biofilms.}, }
@article {pmid39770033, year = {2024}, author = {Skeen, TL and Gresham, RL and Agamaite, KA and Molz, OM and Westlake, IF and Kregenow, SM and Romero, AK and Flood, BM and Mazur, LE and Hinkle, RJ and Young, DD}, title = {Elucidation of Antimicrobials and Biofilm Inhibitors Derived from a Polyacetylene Core.}, journal = {Molecules (Basel, Switzerland)}, volume = {29}, number = {24}, pages = {}, pmid = {39770033}, issn = {1420-3049}, support = {204-01-23//Commonwealth Health Resource Board/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Polyynes/chemistry/pharmacology ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; Molecular Structure ; Anti-Infective Agents/pharmacology/chemistry ; Structure-Activity Relationship ; Bacteria/drug effects ; }, abstract = {The development of new antibiotics with unique mechanisms of action is paramount to combating the growing threat of antibiotic resistance. Recently, based on inspiration from natural products, an asymmetrical polyacetylene core structure was examined for its bioactivity and found to have differential specificity for different bacterial species based on the substituents around the conjugated alkyne. This research further probes the structural requirements for bioactivity through a systematic synthesis and investigation of new compounds with variable carbon chain length, alkynyl subunits, and alcohol substitution. Furthermore, the research examines the activity of the new compounds towards the inhibition of biofilm formation. Overall, several key new polyyne compounds have been identified in both decreasing bacterial viability and in disrupting pre-formed biofilms. These properties are key in the fight against bacterial infections and will be helpful in the further development of new antibiotic agents.}, }
@article {pmid39769141, year = {2024}, author = {Alexa, VT and Fratila, AD and Oancea, R and Galuscan, A and Balean, O and Bolchis, V and Buzatu, BLR and Obistioiu, D and Suleiman, MA and Jumanca, D}, title = {Molecular Docking and Experimental Analysis of Essential Oil-Based Preparations on Biofilm Formation on Orthodontic Archwires.}, journal = {International journal of molecular sciences}, volume = {25}, number = {24}, pages = {}, pmid = {39769141}, issn = {1422-0067}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Molecular Docking Simulation ; *Oils, Volatile/pharmacology/chemistry ; *Orthodontic Wires/microbiology ; *Staphylococcus aureus/drug effects ; *Streptococcus mutans/drug effects ; Humans ; Anti-Bacterial Agents/pharmacology/chemistry ; Stainless Steel/chemistry ; }, abstract = {Good oral hygiene is crucial during treatment with fixed appliances, emphasising the need for additional or alternative oral health methods during orthodontic treatment. This study investigates the effect of essential oil (EO)-based preparations on biofilm adhesion to orthodontic archwires. Five identical-sized orthodontic archwires of different materials were tested using therapeutic and preventive applications of essential oils. This study also used molecular docking to explore how essential oil compounds interact with key proteins of common oral pathogens like Staphylococcus aureus and Streptococcus mutans. We found that the constituent materials heavily influence the antimicrobial effects of essential oils on different orthodontic archwires. Stainless steel-based orthodontic archwires demonstrated the highest efficacy in antimicrobial protection against S. mutans strains (maximum BIP = 28.82% on the epoxy-coated SS). Conversely, inhibition effects in preventive applications against S. aureus were observed exclusively with titanium-molybdenum alloy orthodontic archwires across all tested emulsions (maximum BIP = 29.44%). CuNiTi alloys showed ineffectiveness in preventive treatments, as none of the EO mixtures inhibited biofilm development on this material. After biofilm contamination with S. mutans and S. aureuss strains, the ternary emulsion was most effective for four out of five orthodontic archwires. Computational analysis revealed strong binding interactions between essential oil compounds and key proteins of S. aureus and S. mutans, highlighting specific amino acid residues that are critical for these interactions. Based on the results, stainless steel with epoxy coating or TMA archwires, combined with BEO/CEO/OEO ternary mixture, are recommended for optimal antibacterial protection against biofilm formation on orthodontic archwires.}, }
@article {pmid39768840, year = {2024}, author = {Tsikopoulos, A and Tsikopoulos, K and Sidiropoulos, K and Meroni, G and Triaridis, S and Drago, L and Papaioannidou, P}, title = {Development and Prevention of Biofilm on Cochlear Implants: A Systematic Review.}, journal = {Medicina (Kaunas, Lithuania)}, volume = {60}, number = {12}, pages = {}, pmid = {39768840}, issn = {1648-9144}, mesh = {*Biofilms/drug effects ; *Cochlear Implants/standards/adverse effects ; Humans ; Anti-Bacterial Agents/therapeutic use/pharmacology ; Prosthesis-Related Infections/prevention &amp; control ; Staphylococcus aureus/drug effects/physiology ; }, abstract = {Background and Objectives: Biofilm formation on cochlear implants (CIs) poses a major problem for surgeons, leading to a high incidence of explantation and revision surgery. Therefore, developing appropriate and cost-effective biofilm detection and prevention techniques is of the essence. In this systematic review, we sought to investigate the development of biofilm formation on CIs. We also elaborated on experimental preventative biofilm measures. Materials and Methods: We conducted a systematic search of both in vitro and in vivo literature published in PubMed, Scopus, and ScienceDirect, until 15 June 2024, for published studies evaluating the biofilm formation and strategies for inhibiting biofilm formation on CIs. Depending on the type of the included study, we assessed quality with the modified Consolidated Standards of Reporting Trials tool, the Joanna Briggs Institute Case Reports Critical Appraisal Tool, a modified Delphi technique, and the ROBINS-I tool. We synthesized the available information on biofilm formation on CIs and the infection prevention capacity of the included antibiofilm agents. Results: A total of 26 studies were included in this systematic review. Biofilms in CIs are usually localized in their recesses such as their removable magnet pocket as opposed to their smooth surfaces. S. aureus and P. aeruginosa are the most commonly isolated microorganisms, and they tend to be strong biofilm producers. The optimal treatment strategy for a biofilm-infected CI is explantation. Most of the examined biofilm prevention methods in CIs present sufficient antibiofilm activity. Conclusions: Biofilm formation in CIs is considered one of the most dreadful complications. There have been no specific guidelines for the treatment of those cases, with removal and/or replacement of the CI being the treatment of choice. Various experimental prevention methods provide promising antibiofilm activity both in vivo and in vitro.}, }
@article {pmid39767046, year = {2024}, author = {Yu, X and Li, Y and Yang, X and He, J and Tang, W and Chai, Y and Duan, Z and Li, W and Zhao, D and Wang, X and Huang, A and Li, H and Shi, Y}, title = {Chlorogenic Acid: A Promising Strategy for Milk Preservation by Inhibiting Staphylococcus aureus Growth and Biofilm Formation.}, journal = {Foods (Basel, Switzerland)}, volume = {13}, number = {24}, pages = {}, pmid = {39767046}, issn = {2304-8158}, support = {32302259//the National Natural Science Foundation of China/ ; 202005AD160015//Yunnan Province Technology Innovation Talent Training Object/ ; XDYC-QNRC-2023-0413//the "Yunnan Province 'Xingdian Talent Support Plan' for young talent project"/ ; }, abstract = {Chlorogenic acid (CGA), a polyhydroxy phenolic acid, has been extensively studied for its antimicrobial properties. Staphylococcus aureus (S. aureus) threatens food safety by forming biofilms. This study aimed to investigate the mechanism of CGA against S. aureus and its biofilm. The anti-bacterial activity of CGA was assessed using crystal violet staining, TEM, SEM, a CLSM, and using metabolomics and molecular docking to elucidate the mechanism. The results indicated that the minimum inhibitory concentration of CGA against S. aureus was 2.5 mg/mL. CGA disrupts the integrity of bacterial cell membranes, leading to increased hydrophobicity, morphological changes, scattering, and reduced spreading. This disruption decreases biofilm adhesion and bacterial count. Metabolomics and molecular docking analyses revealed that CGA down-regulates key amino acids. It forms hydrogen bonds with penicillin-binding protein 4 (PBP4), Amidase, glutamate synthetase B, and glutamate synthetase A. By inhibiting amino acid metabolism, CGA prevents biofilm formation. CGA interacts with amino acids such as aspartic acid, glutamine, and glutamate through hydroxyl (-OH) and carbonyl (-C=O) groups. This interaction reduces cell viability and biofilm cohesion. The novel findings of this study, particularly the extension of the shelf life of pasteurized milk by inhibiting S. aureus growth, highlight the potential of CGA as a promising anti-biofilm strategy and preservative in the dairy industry.}, }
@article {pmid39766943, year = {2024}, author = {Unal Turhan, E and Koca, EE}, title = {Predictive Modeling for Inactivation of Escherichia coli Biofilm with Combined Treatment of Thermosonication and Organic Acid on Polystyrene Surface.}, journal = {Foods (Basel, Switzerland)}, volume = {13}, number = {24}, pages = {}, pmid = {39766943}, issn = {2304-8158}, abstract = {The present study aimed to evaluate the antibiofilm effect of combined sonication treatment with organic acids on polystyrene surfaces and to develop a predictive model for the inactivation of Escherichia coli biofilms. Polystyrene plates containing E. coli biofilms were subjected to sonication using different inactivation solutions (PBS, lactic acid, and acetic acid) at varying temperatures (20 °C, 40 °C, and 50 °C) and durations (2 and 5 min). The effects of temperature, treatment duration, and inactivation solution on E. coli biofilm removal were statistically significant (p < 0.05). The use of organic acids, along with increased treatment time and temperature, led to a significant reduction in viable cell counts (0.43-6.21 log CFU/mL) and optical density (0.13-0.72 at OD600) of E. coli biofilms (p < 0.05). The highest E. coli biofilm inactivation, with a reduction of 6.21 CFU/mL and 0.72 OD, was achieved by combining organic acid and thermosonication at 50 °C for 5 min. A significant positive correlation was observed between test methods based on viable cell count and optical density (OD) measurements. According to multiple linear regression analysis results, the R[2] values of the predictive models for biofilm inactivation, based on viable cell count and OD measurements, were 0.84 and 0.80, respectively. Due to its higher accuracy, the predictive model developed using viable cell count data is recommended for applications in the food industry and processing sectors.}, }
@article {pmid39766622, year = {2024}, author = {Hofmeisterová, L and Bajer, T and Walczak, M and Šilha, D}, title = {Chemical Composition and Antibacterial Effect of Clove and Thyme Essential Oils on Growth Inhibition and Biofilm Formation of Arcobacter spp. and Other Bacteria.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {12}, pages = {}, pmid = {39766622}, issn = {2079-6382}, abstract = {Background: In recent years, significant resistance of microorganisms to antibiotics has been observed. A biofilm is a structure that significantly aids the survival of the microbial population and also significantly affects its resistance. Methods: Thyme and clove essential oils (EOs) were subjected to chemical analysis using gas chromatography coupled to mass spectrometry (GC-MS) and gas chromatography with a flame ionization detector (GC-FID). Furthermore, the antimicrobial effect of these EOs was tested in both the liquid and vapor phases using the volatilization method. The effect of the EOs on growth parameters was monitored using an RTS-8 bioreactor. However, the effect of the EOs on the biofilm formation of commonly occurring bacteria with pathogenic potential was also monitored, but for less described and yet clinically important strains of Arcobacter spp. Results: In total, 37 and 28 compounds were identified in the thyme and clove EO samples, respectively. The most common were terpenes and also derivatives of phenolic substances. Both EOs exhibited antimicrobial activity in the liquid and/or vapor phase against at least some strains. The determined antimicrobial activity of thyme and clove oil was in the range of 32-1024 µg/mL in the liquid phase and 512-1024 µg/mL in the vapor phase, respectively. The results of the antimicrobial effect are also supported by similar conclusions from monitoring growth curves using the RTS bioreactor. The effect of EOs on biofilm formation differed between strains. Biofilm formation of Pseudomonas aeruginosa was completely suppressed in an environment with a thyme EO concentration of 1024 µg/mL. On the other hand, increased biofilm formation was found, e.g., in an environment of low concentration (1-32 µg/mL). Conclusions: The potential of using natural matrices as antimicrobials or preservatives is evident. The effect of these EOs on biofilm formation, especially Arcobacter strains, is described for the first time.}, }
@article {pmid39766618, year = {2024}, author = {Yang, Z and Khan, SA and Walsh, LJ and Ziora, ZM and Seneviratne, CJ}, title = {Classical and Modern Models for Biofilm Studies: A Comprehensive Review.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {12}, pages = {}, pmid = {39766618}, issn = {2079-6382}, abstract = {Biofilms are structured microbial communities that adhere to various abiotic and biotic surfaces, where organisms are encased in an exo-polysaccharide matrix. Organisms within biofilms use various mechanisms that help them resist external challenges, such as antibiotics, rendering them more resistant to drugs. Therefore, researchers have attempted to develop suitable laboratory models to study the physical features of biofilms, their resistance mechanisms against antimicrobial agents, and their gene and protein expression profiles. However, current laboratory models suffer from various limitations. In this comprehensive review, we have summarized the various designs that have been used for laboratory biofilm models, presenting their strengths and limitations. Additionally, we have provided insight into improving these models to more closely simulate real-life scenarios, using newly developed techniques in additive manufacturing, synthetic biology, and bioengineering.}, }
@article {pmid39766616, year = {2024}, author = {Osta-Ustarroz, P and Theobald, AJ and Whitehead, KA}, title = {Microbial Colonization, Biofilm Formation, and Malodour of Washing Machine Surfaces and Fabrics and the Evolution of Detergents in Response to Consumer Demands and Environmental Concerns.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {12}, pages = {}, pmid = {39766616}, issn = {2079-6382}, support = {N/A//Lubrizol Coporation/ ; }, abstract = {Bacterial attachment and biofilm formation are associated with the contamination and fouling at several locations in a washing machine, which is a particularly complex environment made from a range of metal, polymer, and rubber components. Microorganisms also adhere to different types of clothing fibres during the laundering process as well as a range of sweat, skin particles, and other components. This can result in fouling of both washing machine surfaces and clothes and the production of malodours. This review gives an introduction into washing machine use and surfaces and discusses how biofilm production confers survival properties to the microorganisms. Microbial growth on washing machines and textiles is also discussed, as is their potential to produce volatiles. Changes in consumer attitudes with an emphasis on laundering and an overview regarding changes that have occurred in laundry habits are reviewed. Since it has been suggested that such changes have increased the risk of microorganisms surviving the laundering process, an understanding of the interactions of the microorganisms with the surface components alongside the production of sustainable detergents to meet consumer demands are needed to enhance the efficacy of new antimicrobial cleaning agents in these complex and dynamic environments.}, }
@article {pmid39766538, year = {2024}, author = {van Leuven, N and Lucassen, R and Dicks, A and Braß, P and Lipski, A and Bockmühl, DP}, title = {Does Antibiotic Use Contribute to Biofilm Resistance in Sink Drains? A Case Study from Four German Hospital Wards.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {12}, pages = {}, pmid = {39766538}, issn = {2079-6382}, abstract = {Backgound. As biofilms are known to harbour (multi-)resistant species, their presence in health settings must be considered critical. Although there is evidence that bacteria spread from drains to the outside, there is still a lack of research data focusing on drain biofilms from hospitals. Methods. We sampled biofilms from various wards of Helios Hospital Krefeld (Germany), where comprehensive antibiotic consumption data were available. Biofilms were analysed by cell counting, isolation of relevant bacterial groups and genetic and phenotypical resistance parameters. Data were correlated with the prescribed antibiotics of the respective ward. Furthermore, an ex situ biofilm model was employed to investigate the influence of sub-inhibitory antibiotics on the bacterial community and the prevalence of class 1 integrons. Results. Our results show that every ward harboured medically relevant bacterial species. While no significant differences were found in cell counts, the median prevalence of the resistance marker gene intI1 correlated with the amount of prescribed antibiotics. In contrast, phenotypical resistances showed no similar tendency. In addition, melting curve analysis data and changes in intI1 prevalence show that the composition of the bacterial community shifted depending on the biofilm and antibiotic. Conclusions. To the best of our knowledge, our study is the first considering possible correlations between the consumption data of hospital wards and resistances in drain biofilms the way we did. Based on our results, we conclude that sub-inhibitory concentrations of antibiotics have no general effect on biofilms in terms of bacterial community shift and occurrence of antibiotic-resistant species. Amongst other things, the effect depends on the initial composition of the bacterial community, the antibiotic used and the intrinsic bacterial resistance, e.g., prevalence of class 1 integrons.}, }
@article {pmid39766522, year = {2024}, author = {Kaushik, A and Kest, H and Sood, M and Thieman, C and Steussy, BW and Padomek, M and Gupta, S}, title = {Infective Endocarditis by Biofilm-Producing Methicillin-Resistant Staphylococcus aureus-Pathogenesis, Diagnosis, and Management.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {12}, pages = {}, pmid = {39766522}, issn = {2079-6382}, abstract = {Infective endocarditis (IE) is a life-threatening condition with increasing global incidence, primarily caused by Staphylococcus aureus, especially methicillin-resistant strains (MRSA). Biofilm formation by S. aureus is a critical factor in pathogenesis, contributing to antimicrobial resistance and complicating the treatment of infections involving prosthetic valves and cardiovascular devices. Biofilms provide a protective matrix for MRSA, shielding it from antibiotics and host immune defenses, leading to persistent infections and increased complications, particularly in cases involving prosthetic materials. Clinical manifestations range from acute to chronic presentations, with complications such as heart failure, embolic events, and neurological deficits. Diagnosis relies on the Modified Duke Criteria, which have been updated to incorporate modern cardiovascular interventions and advanced imaging techniques, such as PET/CT (positron emission tomography, computed tomography), to improve the detection of biofilm-associated infections. Management of MRSA-associated IE requires prolonged antimicrobial therapy, often with vancomycin or daptomycin, needing a combination of antimicrobials in the setting of prosthetic materials and frequently necessitates surgical intervention to remove infected prosthetic material or repair damaged heart valves. Anticoagulation remains controversial, with novel therapies like dabigatran showing potential benefits in reducing thrombus formation. Despite progress in treatment, biofilm-associated resistance poses ongoing challenges. Emerging therapeutic strategies, including combination antimicrobial regimens, bacteriophage therapy, antimicrobial peptides (AMPs), quorum sensing inhibitors (QSIs), hyperbaric oxygen therapy, and nanoparticle-based drug delivery systems, offer promising approaches to overcoming biofilm-related resistance and improving patient outcomes. This review provides an overview of the pathogenesis, current management guidelines, and future directions for treating biofilm-related MRSA IE.}, }
@article {pmid39766503, year = {2024}, author = {Oh, JW and Shin, MK and Park, HR and Kim, S and Lee, B and Yoo, JS and Chi, WJ and Sung, JS}, title = {PA-Win2: In Silico-Based Discovery of a Novel Peptide with Dual Antibacterial and Anti-Biofilm Activity.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {12}, pages = {}, pmid = {39766503}, issn = {2079-6382}, support = {NIBRE202411//National Institute of Biological Resources/ ; NIBR202402105//National Institute of Biological Resources/ ; }, abstract = {Background: The emergence and prevalence of antibiotic-resistant bacteria (ARBs) have become a serious global threat, as the morbidity and mortality associated with ARB infections are continuously rising. The activation of quorum sensing (QS) genes can promote biofilm formation, which contributes to the acquisition of drug resistance and increases virulence. Therefore, there is an urgent need to develop new antimicrobial agents to control ARB and prevent further development. Antimicrobial peptides (AMPs) are naturally occurring defense molecules in organisms known to suppress pathogens through a broad range of antimicrobial mechanisms. Methods: In this study, we utilized a previously developed deep-learning model to identify AMP candidates from the venom gland transcriptome of the spider Pardosa astrigera, followed by experimental validation. Results: PA-Win2 was among the top-scoring predicted peptides and was selected based on physiochemical features. Subsequent experimental validation demonstrated that PA-Win2 inhibits the growth of Bacillus subtilis, Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and multidrug-resistant P. aeruginosa (MRPA) strain CCARM 2095. The peptide exhibited strong bactericidal activity against P. aeruginosa, and MRPA CCARM 2095 through the depolarization of bacterial cytoplasmic membranes and alteration of gene expression associated with bacterial survival. In addition, PA-Win2 effectively inhibited biofilm formation and degraded pre-formed biofilms of P. aeruginosa. The gene expression study showed that the peptide treatment led to the downregulation of QS genes in the Las, Pqs, and Rhl systems. Conclusions: These findings suggest PA-Win2 as a promising drug candidate against ARB and demonstrate the potential of in silico methods in discovering functional peptides from biological data.}, }
@article {pmid39764613, year = {2025}, author = {Xiong, T and Ning, F and Chen, Y and Gu, M and Li, M and Chen, X and Wang, L and Fan, J and Peng, X}, title = {Charge Regulation-Enhanced Type I Photosensitizer-Loaded Hydrogel Dressing for Hypoxic Bacterial Inhibition and Biofilm Elimination.}, journal = {ACS nano}, volume = {19}, number = {2}, pages = {2822-2833}, doi = {10.1021/acsnano.4c15730}, pmid = {39764613}, issn = {1936-086X}, mesh = {*Biofilms/drug effects ; *Photosensitizing Agents/pharmacology/chemistry ; *Hydrogels/chemistry/pharmacology ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Photochemotherapy ; *Bandages ; Animals ; Mice ; Microbial Sensitivity Tests ; Staphylococcus aureus/drug effects ; Pseudomonas aeruginosa/drug effects ; Humans ; }, abstract = {Biofilm-induced chronic bacterial infections represent a significant challenge in modern medicine due to their resistance to conventional antibiotic treatments. Although photodynamic therapy (PDT) has emerged as a promising antibiotic-free antibacterial strategy, the hypoxic condition within biofilms and the lack of an effective local drug delivery system have limited the clinical effectiveness of photosensitizer (PS) agents. Herein, we propose a type of charge regulation-enhanced type I PS-loaded hydrogel dressing for treating biofilm infection. The charge regulation enables the multiple alkylation Nile blue (EB series) to exhibit substantially improved absorbance (∼2-fold), alkaline tolerance, and superoxide anion yield (2.2-4.2-fold) compared to the representative type I PS, sulfur-substituted Nile blue. Specifically, the enhanced electronic push-pull capabilities promote a more efficient electron recycling process, significantly boosting the efficiency of type I PDT. The superior PDT effect and enhanced bacterial uptake via charge regulation render the EB series more pronounced in hypoxic bacterial inhibition under red light or sunlight irradiation. Moreover, the hydrogel, constructed from oxidized dextran and quaternized chitosan, facilitates the localization and sustained retention of type I PSs, accelerating the healing of biofilm-infected wounds. This type I PS-based hydrogel could provide an efficient and user-friendly wound dressing for the clinical treatment and prevention of biofilm infections.}, }
@article {pmid39764404, year = {2024}, author = {Sengupta, B and Alrubayan, M and Wang, Y and Mallet, E and Torres, A and Solis, R and Wang, H and Pradhan, P}, title = {An AI-directed analytical study on the optical transmission microscopic images of Pseudomonas aeruginosa in planktonic and biofilm states.}, journal = {ArXiv}, volume = {}, number = {}, pages = {}, pmid = {39764404}, issn = {2331-8422}, support = {R03 DE032766/DE/NIDCR NIH HHS/United States ; R21 CA260147/CA/NCI NIH HHS/United States ; }, abstract = {Biofilms are resistant microbial cell aggregates that pose risks to health and food industries and produce environmental contamination. Accurate and efficient detection and prevention of biofilms are challenging and demand interdisciplinary approaches. This multidisciplinary research reports the application of a deep learning-based artificial intelligence (AI) model for detecting biofilms produced by Pseudomonas aeruginosa with high accuracy. Aptamer DNA templated silver nanocluster (Ag-NC) was used to prevent biofilm formation, which produced images of the planktonic states of the bacteria. Large-volume bright field images of bacterial biofilms were used to design the AI model. In particular, we used U-Net with ResNet encoder enhancement to segment biofilm images for AI analysis. Different degrees of biofilm structures can be efficiently detected using ResNet18 and ResNet34 backbones. The potential applications of this technique are also discussed.}, }
@article {pmid39764008, year = {2024}, author = {Zarate, D and Isenberg, RY and Pavelsky, M and Speare, L and Jackson, A and Mandel, MJ and Septer, AN}, title = {The conserved global regulator H-NS has a strain-specific impact on biofilm formation in Vibrio fischeri symbionts.}, journal = {bioRxiv : the preprint server for biology}, volume = {}, number = {}, pages = {}, pmid = {39764008}, issn = {2692-8205}, support = {R35 GM137886/GM/NIGMS NIH HHS/United States ; R35 GM148385/GM/NIGMS NIH HHS/United States ; T32 GM007215/GM/NIGMS NIH HHS/United States ; }, abstract = {UNLABELLED: Strain-level variation among host-associated bacteria often determines host range and the extent to which colonization is beneficial, benign, or pathogenic. Vibrio fischeri is a beneficial symbiont of the light organs of fish and squid with known strain-specific differences that impact host specificity, colonization efficiency, and interbacterial competition. Here, we describe how the conserved global regulator, H-NS, has a strain-specific impact on a critical colonization behavior: biofilm formation. We isolated a mutant of the fish symbiont V. fischeri MJ11 with a transposon insertion in the hns gene. This mutant formed sticky, moderately wrinkled colonies on LBS plates, a condition not known to induce biofilm in this species. A reconstructed hns mutant displayed the same wrinkled colony, which became smooth when hns was complemented in trans, indicating the hns disruption is causal for biofilm formation in MJ11. Transcriptomes revealed differential expression for the syp biofilm locus in the hns mutant, relative to the parent, suggesting biofilm may in part involve SYP polysaccharide. However, enhanced biofilm in the MJ11 hns mutant was not sufficient to allow colonization of a non-native squid host. Finally, moving the hns mutation into other V. fischeri strains, including the squid symbionts ES114 and ES401, and seawater isolate PP3, revealed strain-specific biofilm phenotypes: ES114 and ES401 hns mutants displayed minimal biofilm phenotypes while PP3 hns mutant colonies were more wrinkled than the MJ11 hns mutant. These findings together define H-NS as a novel regulator of V. fischeri symbiotic biofilm and demonstrate key strain specificity in that role.<br><br>IMPORTANCE: This work, which shows how H-NS has strain-specific impacts on biofilm in Vibrio fischeri, underscores the importance of studying multiple strains, even when examining highly conserved genes and functions. Our observation that knocking out a conserved regulator can result in a wide range of biofilm phenotypes, depending on the isolate, serves as a powerful reminder that strain-level variation is common and worthy of exploration. Indeed, uncovering the mechanisms of strain-specific phenotypic differences is essential to understand drivers of niche differentiation and bacterial evolution. Thus, it is important to carefully match the number and type of strains used in a study with the research question to accurately interpret and extrapolate the results beyond a single genotype. The additional work required for multi-strain studies is often worth the investment of time and resources, as it provides a broader view of the complexity of within-species diversity in microbial systems.}, }
@article {pmid39763928, year = {2024}, author = {Glowacki, RWP and Engelhart, MJ and Till, JM and Kadam, A and Nemet, I and Sangwan, N and Ahern, PP}, title = {Identification of strain-specific cues that regulate biofilm formation in Bacteroides thetaiotaomicron.}, journal = {bioRxiv : the preprint server for biology}, volume = {}, number = {}, pages = {}, doi = {10.1101/2024.12.20.629428}, pmid = {39763928}, issn = {2692-8205}, abstract = {UNLABELLED: Members of the gut microbiome encounter a barrage of host- and microbe-derived microbiocidal factors that must be overcome to maintain fitness in the intestine. The long-term stability of many gut microbiome strains within the microbiome suggests the existence of strain-specific strategies that have evolved to foster resilience to such insults. Despite this, little is known about the mechanisms that mediate this resistance. Biofilm formation represents one commonly employed defense strategy against stressors like those found in the intestine. Here, we demonstrate strain-level variation in the capacity of the gut symbiont Bacteroides thetaiotaomicron to form biofilms. Despite the potent induction of biofilm formation by purified bile in most strains, we show that the specific bile acid species driving biofilm formation differ among strains, and uncover that a secondary bile-acid, lithocholic acid, and its conjugated forms, potently induce biofilm formation in a strain-specific manner. Additionally, we found that the short-chain fatty acid, acetic acid, could suppress biofilm formation. Thus, our data defines the molecular components of bile that promote biofilm formation in B. thetaiotaomicron and reveals that distinct molecular cues trigger the induction or inhibition of this process. Moreover, we uncover strain-level variation in these responses, thus identifying that both shared and strain-specific determinants govern biofilm formation in this species.<br><br>IMPORTANCE: In order to thrive within the intestine, it is imperative that gut microbes resist the multitude of insults derived from the host immune system and other microbiome members. As such, they have evolved strategies that ensure their survival within the intestine. We investigated one such strategy, biofilm formation, in Bacteroides thetaiotaomicron , a common member of the human microbiome. We uncovered significant variation in natural biofilm formation in the absence of an overt stimulus among different Bacteroides thetaiotaomicron strains, and revealed that different strains adopted a biofilm lifestyle in response to distinct molecular stimuli. Thus our studies provide novel insights into factors mediating gut symbiont resiliency, revealing strain-specific and shared strategies in these responses. Collectively, our findings underscore the prevalence of strain-level differences that should be factored into our understanding of gut microbiome functions.}, }
@article {pmid39763852, year = {2024}, author = {Liu, Y and Gates, AD and Liu, Z and Duque, Q and Chen, MY and Hamilton, CD and O'Toole, GA and Haney, CH}, title = {In vitro biofilm formation only partially predicts beneficial Pseudomonas fluorescens protection against rhizosphere pathogens.}, journal = {bioRxiv : the preprint server for biology}, volume = {}, number = {}, pages = {}, pmid = {39763852}, issn = {2692-8205}, support = {R01 GM123609/GM/NIGMS NIH HHS/United States ; }, abstract = {Plant roots form associations with both beneficial and pathogenic soil microorganisms. While members of the rhizosphere microbiome can protect against pathogens, the mechanisms are poorly understood. We hypothesized that the ability to form a robust biofilm on the root surface is necessary for the exclusion of pathogens; however, it is not known if the same biofilm formation components required in vitro are necessary in vivo. Pseudomonas fluorescens WCS365 is a beneficial strain that is phylogenetically closely related to an opportunistic pathogen P. fluorescens N2C3 and confers robust protection against P. fluorescens N2C3 in the rhizosphere. We used this plant-mutualist-pathogen model to screen collections of P. fluorescens WCS365 increased attachment mutants (iam) and surface attachment defective (sad) transposon insertion mutants that form increased or decreased levels of biofilm on an abiotic surface, respectively. We found that while the P. fluorescens WCS365 mutants had altered biofilm formation in vitro, only a subset of these mutants, including those involved in large adhesion protein (Lap) biosynthesis, flagellin biosynthesis and O-antigen biosynthesis, lost protection against P. fluorescens N2C3. We found that the inability of P. fluorescens WCS365 mutants to grow in planta, and the inability to suppress pathogen growth, both partially contributed to loss of plant protection. We did not find a correlation between the extent of biofilm formed in vitro and pathogen protection in planta indicating that biofilm formation on abiotic surfaces may not fully predict pathogen exclusion in planta. Collectively, our work provides insights into mechanisms of biofilm formation and host colonization that shape the outcomes of host-microbe-pathogen interactions.}, }
@article {pmid39761772, year = {2025}, author = {Padmavathi, AR and Karthikeyan, B and Rao, TS and Senthil Kumar, J and Murthy, PS}, title = {Polydimethylsiloxane loaded capsaicin afflicts membrane integrity, metabolic activity and biofilm formation of nosocomial pathogens.}, journal = {Microbial pathogenesis}, volume = {200}, number = {}, pages = {107282}, doi = {10.1016/j.micpath.2025.107282}, pmid = {39761772}, issn = {1096-1208}, abstract = {Biofilms constitute 80 % of all nosocomial infections associated with invasive medical devices. Polydimethylsiloxane, a highly elastic, inert, non-reactive, biocompatible silicone polymer is widely used as implant biomaterial due to its non-toxic and low-immunogenic nature. Owing to its hydrophobicity, PDMS suffers from microbial adhesion. Inhibition of biofilm formation on PDMS surfaces is imperative to prevent morbidity, mortality and replacement of implants. The present study investigates the efficacy of capsaicin (0.5 % w/v) loaded PDMS as a broad spectrum antimicrobial surface against Staphylococcus aureus, Escherichia coli and Candida albicans. Capsaicin exhibited minimum inhibitory concentration of 1024 μg mL[-1] for S. aureus, E. coli and 256 μg mL[-1] for C. albicans. Capsaicin inhibited biofilms of S. aureus, E. coli and C. albicans at much lower concentrations of 2, 64 and 8 μg mL[-1] respectively. The minimum capsaicin concentrations required for total biofilm eradication was found to be 256, 512, 128 μg mL[-1] for S. aureus, E. coli and C. albicans respectively. Probing sub-lethal concentrations of capsaicin revealed 38, 32, 30 % reduction in metabolic activity of S. aureus, E. coli &amp; C. albicans planktonic cells respectively. Similarly, there was an increase in permeability of cells to propidium iodide compared to control. By reducing the metabolic activity and perturbing membrane integrity, capsaicin could prevent biofilm formation and this was also observed with capsaicin-PDMS surfaces that exhibited 1 log (∼90 %) reduction of viable bacterial counts.}, }
@article {pmid39761771, year = {2025}, author = {Benahmed, A and Seghir, A and Dergal, F and Chiali, A and Boucherit-Otmani, Z and Ziani-Chérif, C}, title = {Study of interaction in dual-species biofilm of Candida glabrata and Klebsiella pneumoniae co-isolated from peripheral venous catheter using Raman characterization mapping and machine learning algorithms.}, journal = {Microbial pathogenesis}, volume = {199}, number = {}, pages = {107280}, doi = {10.1016/j.micpath.2025.107280}, pmid = {39761771}, issn = {1096-1208}, mesh = {*Biofilms/growth &amp; development ; *Klebsiella pneumoniae/physiology/isolation &amp; purification ; *Machine Learning ; *Spectrum Analysis, Raman/methods ; *Candida glabrata/physiology/isolation &amp; purification ; Humans ; Microscopy, Electron, Scanning ; Microbial Interactions ; Algorithms ; Coinfection/microbiology ; Catheter-Related Infections/microbiology ; Klebsiella Infections/microbiology ; }, abstract = {Polymicrobial biofilm infections, especially associated with medical devices such as peripheral venous catheters, are challenging in clinical settings for treatment and management. In this study, we examined the mixed biofilm formed by Candida glabrata and Klebsiella pneumoniae, which were co-isolated from the same peripheral venous catheter. Our results revealed that C. glabrata can form mixed biofilms with K. pneumoniae in vitro on peripheral venous catheters and the bottom of microplate wells, as confirmed by scanning electron microscopy. Additionally, using Raman mapping, we showed the distribution of both species in mono- and dual-species biofilms and suggested the type of microbial interaction in this polymicrobial biofilm. Finally, with the assistance of appropriate machine learning (ML) algorithms, based on identified peaks of bacteria, yeast, catheter, and Microplate mapping spectra, we develop a dedicated Raman database to detect the presence of these elements in an unknown spectrum in the future.}, }
@article {pmid39758814, year = {2025}, author = {Ribeiro, PDS and Stasko, J and Shircliff, A and Fernandes, LG and Putz, EJ and Andreasen, C and Azevedo, V and Ristow, P and Nally, JE}, title = {Investigations into the growth and formation of biofilm by Leptospira biflexa at temperatures encountered during infection.}, journal = {Biofilm}, volume = {9}, number = {}, pages = {100243}, pmid = {39758814}, issn = {2590-2075}, abstract = {The genus Leptospira comprises unique atypical spirochete bacteria that includes the etiological agent of leptospirosis, a globally important zoonosis. Biofilms are microecosystems composed of microorganisms embedded in a self-produced matrix that offers protection against hostile factors. Leptospires form biofilms in vitro, in situ in rice fields and unsanitary urban areas, and in vivo while colonizing rodent kidneys. The complex three-dimensional biofilm matrix includes secreted polymeric substances such as proteins, extracellular DNA (eDNA), and saccharides. The genus Leptospira comprises pathogenic and saprophytic species with the saprophytic L. biflexa being commonly used as a model organism for the genus. In this study, the growth and formation of biofilms by L. biflexa was investigated not just at 29 °C, but at 37 °C/5 % CO2, a temperature similar to that encountered during host infection. Planktonic free-living L. biflexa grow in HAN media at both 29 °C and 37 °C/5 % CO2, but cells grown at 37 °C/5 % CO2 are longer (18.52 μm ± 3.39) compared to those at 29 °C (13.93 μm ± 2.84). Biofilms formed at 37 °C/5 % CO2 had more biomass compared to 29 °C, as determined by crystal violet staining. Confocal microscopy determined that the protein content within the biofilm matrix was more prominent than double-stranded DNA, and featured a distinct layer attached to the solid substrate. Additionally, the model enabled effective protein extraction for proteomic comparison across different biofilm phenotypes. Results highlight an important role for proteins in biofilm matrix structure by leptospires and the identification of their specific protein components holds promise for strategies to mitigate biofilm formation.}, }
@article {pmid39758150, year = {2024}, author = {Yadav, P and Shrestha, S and Basyal, D and Tiwari, A and Sah, R and Sah, AK and Yadav, B and Willcox, M and Mishra, SK}, title = {Characterization and Biofilm Inhibition of Multidrug-Resistant Acinetobacter baumannii Isolates.}, journal = {International journal of microbiology}, volume = {2024}, number = {}, pages = {5749982}, pmid = {39758150}, issn = {1687-918X}, abstract = {Multidrug-resistant (MDR) Acinetobacter baumannii poses a significant therapeutic challenge due to its resistance to multiple antibiotics and its ability to form biofilm. This study aimed to characterize MDR A. baumannii isolates for their biofilm-forming capabilities and the presence of common biofilm-related genes at a tertiary care university hospital in Nepal. In addition, it assessed the efficacy of various compounds, particularly essential oils, in inhibiting biofilm formation. Identification and antibiotic sensitivity testing of A. baumannii isolates from clinical specimens were conducted according to the guidelines of the American Society for Microbiology. Isolates were screened for motility profiles, biofilm production in a microtiter plate assay, and the presence of biofilm-related gene(s) by conventional polymerase chain reaction. The ability of cinnamaldehyde, ethylenediaminetetraacetic acid (EDTA), Tween 80, amino acids (glycine and glutamic acid), and natural plant extracts to inhibit biofilm formation was also tested using the microtiter plate system. Out of the total 200 A. baumannii isolates, 195 were MDR, with 192 able to produce biofilms. Among them, 83.1% were strong biofilm producers. In this study, 42.0% and 66.2% of the isolates exhibited twitching motility and surface-associated motility, respectively. Thirty MDR A. baumannii isolates from medical devices contained biofilm-related genes csuE, ompA, bap, and bla PER-1, in 90.0%, 53.3%, 46.6%, and 26.6% of strains, respectively. Cinnamaldehyde (0.875 mg/mL) was the most effective compound, inhibiting biofilm formation by 77.3%, followed by ethanolic extract of onion (77.2%), 0.5% Tween 80 (76.8%), and essential oil of ginger (70.8%). The majority of A. baumannii clinical isolates were strong biofilm producers and often possessed the biofilm-related genes csuE and ompA. Essential oils at 200 mg/L, along with Tween 80, were the most effective (≥ 67%) at inhibiting the formation of biofilms. These findings help to understand biofilm production and provide valuable insights into MDR A. baumannii isolates in this clinical setting.}, }
@article {pmid39757612, year = {2024}, author = {Banerjee, D and Biswas, P and Mazumder, K and Palai, S and Hossain, CM and Karmakar, S and Biswas, K}, title = {Exploration of Phytochemicals as Anti-biofilm Agents Against Pathogenic Bacteria: Their Potential and Challenges.}, journal = {Infectious disorders drug targets}, volume = {}, number = {}, pages = {}, doi = {10.2174/0118715265324950241204182204}, pmid = {39757612}, issn = {2212-3989}, abstract = {Multicellular surface-attached populations of bacteria embedded in the extracellular matrix are known as biofilms. Bacteria generally preferred to grow as biofilms. Quorum sensing (QS), detection of density of cell population through gene regulation, has been found to play an important role in the production of biofilms. Biofilm formation can increase the severity of infections that can lead to morbidity or mortality. Bacteria living within biofilms have a higher pattern of adaptive resistance to antibiotics. Antibiotic resistance is a barrier in the treatment of biofilmsinduced acute to chronic infections such as post-surgery infections, surgery-associated wound infections, endocarditis, joint infections, burn-related wound infections occurred, ventilator-associated pneumonia, etc. So it is urgent to discover or find out potent new drugs in fight against infectious diseases such as biofilms-associated infections. Medicinal plants or herbs are a rich source for fighting with biofilms-mediated infections. Phytochemicals have exhibited significant effects in the prevention of biofilms formation against different bacteria that are causing infections. Purified compounds such as berberine, tetrandrine, embelin, xanthorrhizol, bakuchiol, etc., exhibited promising biofilm inhibition actions against different pathogenic bacteria. Plant extracts that contain several phytochemicals are evaluated for its biofilm's inhibition property, and have shown significant potential in biofilm formation. Antibiofilm agents act by distinct mechanisms such as inhibiting the adherence of biofilms in a surface, preventing the biofilm formations, disrupting the matured biofilms, etc. This study is intended to reiterate about possibilities of plant extracts and purified compounds in the treatment of the prevention of bacterial biofilms-related infections.}, }
@article {pmid39757571, year = {2025}, author = {Vaikkathillam, P and Mini, M and Mohan, A and Jayakumar, D and Rajan, PP and Asha, S and Kumar, P}, title = {Anti-biofilm effect of ferulic acid against Enterobacter hormaechei and Klebsiella pneumoniae: in vitro and in silico investigation.}, journal = {Biofouling}, volume = {41}, number = {2}, pages = {157-170}, doi = {10.1080/08927014.2024.2446927}, pmid = {39757571}, issn = {1029-2454}, mesh = {*Biofilms/drug effects ; *Klebsiella pneumoniae/drug effects/physiology ; *Enterobacter/drug effects/physiology ; *Coumaric Acids/pharmacology/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Molecular Docking Simulation ; Molecular Dynamics Simulation ; Microbial Sensitivity Tests ; Computer Simulation ; Bacterial Proteins ; }, abstract = {Enterobacter hormaechei and Klebsiella pneumoniae, key members of the ESKAPE group of hospital-acquired pathogens, are driving forces behind numerous infections due to their potent biofilm formation and the growing threat of antimicrobial resistance. Ferulic acid (FA) is known for its strong antioxidant properties and is recognized for its numerous physiological benefits, including anti-inflammatory, antimicrobial, anticancer, and antidiabetic effects. The current investigation delves into the antimicrobial and antibiofilm ability of FA against E. hormaechei and K. pneumoniae. Using different assays, we confirmed that FA inhibits the biofilm formation of these pathogens. Through computational studies involving molecular docking and molecular dynamics simulations, it was found that FA exhibits a strong affinity for binding with MrkB in E. hormaechei and MrkH in K. pneumoniae, crucial proteins involved in biofilm formation. We hypothesise that FA might interfere with adhesion-associated molecules and inhibit biofilms through the c-di-GMP pathway and proves as an effective antibiofilm compound.}, }
@article {pmid39757558, year = {2025}, author = {Li, C and Xin, W}, title = {Different Disinfection Strategies in Bacterial and Biofilm Contamination on Dental Unit Waterlines: A Systematic Review.}, journal = {International journal of dental hygiene}, volume = {}, number = {}, pages = {}, doi = {10.1111/idh.12899}, pmid = {39757558}, issn = {1601-5037}, support = {220513116490573//Science and Technology Planning Project of Shantou City/ ; 002-181233120//Provincial Quality Engineering Project Dentistry Experimental Teaching Demonstration Centre/ ; }, abstract = {OBJECTIVE: The aim of this systematic review is to explore the effectiveness of different methods of reducing contamination and biofilms in dental unit waterlines (DUWLs) and to provide reference for future standardisation of disinfection practices in dental clinic.<br><br>METHODS: This systematic review searched PubMed and Web of Science databases for DUWL disinfection studies from 2013 to 2023, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and Synthesis Without Meta-analysis, additional extracting relevant data based on predefined inclusion and exclusion criteria.<br><br>RESULTS: The study review identified 8442 articles, with 58 included after rigorous screening. Disinfection methods for DUWLs were categorised into 14 physical and 90 chemical methods. Peroxides, chloramine-based, and biguanide methods were frequently used, often in combination. The effectiveness of these methods varied; for instance, phenolic was effective, while alcohol was not, in reducing bacterial and biofilm contamination. Biguanide, when used alone or combined with chlorine-based or alcohol, showed mixed results. Chlorine-based methods, particularly when combined with quaternary ammonium salt or enzymes, were generally effective. Enzymes and iodophor also demonstrated efficacy, though with some inconsistencies. Mechanical systems, peroxides, quaternary ammonium salts, silver, and tube coatings had varying degrees of success. Other innovative methods, such as Aloe vera and slightly acidic electrolysed water, showed promise in some studies, but the effectiveness of flushing was questioned. This comprehensive analysis highlights the diversity and complexity of disinfection strategies for DUWLs.<br><br>CONCLUSION: Future studies should focus on how material composition and tubing design affect biofilm development and the effectiveness of disinfection methods to guide the design of advanced dental units.}, }
@article {pmid39757480, year = {2025}, author = {Kralj, S and Da Silva, C and Nemec, S and Caf, M and Fourquaux, I and Rols, MP and Golzio, M and Mertelj, A and Kolosnjaj-Tabi, J}, title = {Dynamically Assembling Magnetic Nanochains as New Generation of Swarm-Type Magneto-Mechanical Nanorobots Affecting Biofilm Integrity.}, journal = {Advanced healthcare materials}, volume = {}, number = {}, pages = {e2403736}, doi = {10.1002/adhm.202403736}, pmid = {39757480}, issn = {2192-2659}, support = {ANR-23-CE18-0029-01//French national research agency/ ; P2-0089//Slovenian Research and Innovation Agency/ ; J2-60047//Slovenian Research and Innovation Agency/ ; J2-3043//Slovenian Research and Innovation Agency/ ; J2-3040//Slovenian Research and Innovation Agency/ ; J2-3046//Slovenian Research and Innovation Agency/ ; J3-3079//Slovenian Research and Innovation Agency/ ; J7-4420//Slovenian Research and Innovation Agency/ ; BI-FR/23-24-PROTEUS-005(PR-12039)//Campus France/ ; BI-RS/23-25-030(PR-12782)//Campus France/ ; PHC-PROTEUS-France-Slovenia-48879QJ//Campus France/ ; }, abstract = {Bacterial resistance is gaining ground and novel, unconventional strategies are required to improve antibiotic treatments. As a synthetic analog of planktonic bacilli, the natural bacterial swimmers that can penetrate bacterial biofilms, ultra-short propelling magnetic nanochains are presented as bioinspired magnetic nanorobots, enhancing the antibiotic treatment in biofilm-forming Staphylococcus epidermidis. Propelling nanochains, activated by a low intensity (<20 mT) and low frequency (<10 Hz) rotating magnetic field (RMF), prompt the otherwise resistant biofilm-forming bacteria to become sensitive to methicillin, resulting in the killing of 99.99% of bacteria. While magnetic force-driven spherical magnetic nanoparticles were previously reported as unidirectional biofilm channel diggers, propelling nanochains emerge as second-generation magnetic nanorobots, which, due to their magnetic core, shape anisotropy, and negative zeta potential, combine magnetic responsiveness, torque-driven movement, and attractive electrostatic interactions to attach to bacterial aggregates and multi-directionally protrude throughout the biofilm, indulging mechanical forces. These synergistic effects, in combination with an antibiotic drug, destroy the bacterial extracellular matrix and eradicate the formed biofilm, as confirmed with several complementary techniques.}, }
@article {pmid39756997, year = {2025}, author = {Chen, YS and Chien, AS and Li, CC and Lin, CC and Wu, RJ}, title = {Effects of Commonly Used Vegetable Oils on Skin Barrier Function and Staphylococcus aureus Biofilm.}, journal = {Journal of oleo science}, volume = {74}, number = {1}, pages = {97-106}, doi = {10.5650/jos.ess24032}, pmid = {39756997}, issn = {1347-3352}, mesh = {*Biofilms/drug effects ; *Staphylococcus aureus/drug effects ; Animals ; *Filaggrin Proteins ; Mice ; *Plant Oils/pharmacology ; NIH 3T3 Cells ; *Keratinocytes/drug effects ; *Skin/drug effects ; *Wound Healing/drug effects ; Fibroblasts/drug effects ; Collagen/metabolism ; Sodium Dodecyl Sulfate/pharmacology ; Sunflower Oil ; Olive Oil/pharmacology/chemistry ; Surface-Active Agents/pharmacology ; Dose-Response Relationship, Drug ; }, abstract = {Adding of vegetable oils to skincare products or the use of plant oils for oil care is a current trend. Therefore, the safety and functionality of vegetable oils are of great concern to consumers and cosmetics manufacturers. This study focused on three types of vegetable oils: sunflower oil (SO), andiroba oil (AO) and hydrogenated olive oil (HOO). We conducted a comprehensive evaluation of the oils, which encompassed their ability to protect mouse skin keratinocytes (XB-2) and mouse fibroblasts (NIH 3T3) from damage caused by the surfactant sodium lauryl sulfate (SLS), their influence on the levels of filaggrin and collagen, their potential to aid in wound healing, and their effectiveness in anti-Staphylococcus aureus biofilm formation. The results showed that SO, AO and HOO at a concentration of 1.5 × 10[-4] % (v/v) have the ability to defend against SLS-induced cell damage, increase wound healing ability and the filaggrin and collagen content to XB-2 or NIH 3T3 cells. SO, AO and HOO at a concentration of 3.75 × 10[-3] % also have the anti-biofilm ability. Among the oils, AO can inhibit S. aureus biofilm composed of either polysaccharides or proteins. Therefore, the tested vegetable oils and can be applied to the cosmetics field as ingredients to repair damaged skin and preserve skin barrier stability.}, }
@article {pmid39756524, year = {2025}, author = {Upadhyay, A and Jaiswal, N and Kumar, A}, title = {Biofilm battle: New transformative tactics to tackle the bacterial biofilm infections.}, journal = {Microbial pathogenesis}, volume = {199}, number = {}, pages = {107277}, doi = {10.1016/j.micpath.2025.107277}, pmid = {39756524}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; Humans ; *Bacterial Infections/therapy/prevention &amp; control/microbiology ; *Anti-Bacterial Agents/pharmacology/therapeutic use ; *Bacteria/drug effects ; Phage Therapy ; Bacterial Physiological Phenomena ; }, abstract = {Bacterial biofilm infections are the root cause of persistent infections and the prevalence of resistance to specific or multiple antibiotics. Biofilms have unique features that provide a protective environment for bacteria under various stress conditions and contribute significantly to the pathogenesis of chronic infections. They cover bacterial cells with a self-produced extracellular polymeric matrix, effectively hiding the bacterial cells and their targets. Conventional therapies cannot effectively treat and control bacterial biofilm infections. Therefore, advanced therapeutic means like microneedles, targeted tissue therapy, phage therapy, nanodrug therapy, combination drug therapy, microbial therapy, and immune cell hijacking therapy are needed to tackle the complex issue. These advanced therapies have shown promising results not only in bacterial biofilm infections but also in diseases such as cancer and genetic disorders. Due to their unique features and mechanisms, they significantly contribute to preventing bacterial infections by disrupting biofilm. This article aims to serve as a comprehensive overview of the ongoing battle against biofilms with transformative therapies. This article compiles advancements in new therapies that have demonstrated effective roles in the disruption of bacterial biofilms. We also discuss the current developments and Food and Drug Administration-approved status of these therapies. Additionally, this article summarizes the limitations and future steps needed for these therapies in the field of bacterial biofilm prevention. Thus, these therapies represent the future of preventing bacterial biofilm infections and could be also effective in the reversal of resistance.}, }
@article {pmid39756377, year = {2025}, author = {Vimalanathan, V and Hasan, H and Kunasegaran, V and Sarawanan, K and Ilangovan, M and Sandrasaigaran, P}, title = {Rice husk- and lemongrass-derived eco-enzymes as potential food contact surface disinfectants against biofilm-forming foodborne pathogens.}, journal = {FEMS microbiology letters}, volume = {372}, number = {}, pages = {}, doi = {10.1093/femsle/fnae116}, pmid = {39756377}, issn = {1574-6968}, support = {//Department of Biotechnology/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Disinfectants/pharmacology ; *Oryza/microbiology ; *Pseudomonas aeruginosa/drug effects/physiology ; *Food Microbiology ; *Staphylococcus aureus/drug effects/physiology ; *Salmonella typhimurium/drug effects ; Microbial Sensitivity Tests ; }, abstract = {This study aims to evaluate the rice husk (EE-R)- and lemongrass (EE-L)-derived eco-enzymes (EE) as alternatives to chemical-based disinfectants. The EE-R's and EE-L's antimicrobial activity were tested against Pseudomonas aeruginosa, Salmonella Typhimurium, and Staphylococcus aureus using a broth microdilution method. The antibiofilm activities of EE were determined using crystal violet staining. Lastly, the minimal contact time of EE for effectively reducing biofilm-forming pathogens (<25 CFU/ml) was assessed on various food contact surfaces (wood, glass, plastic, stainless steel, and marble). The results show that EE-R at 25%-50% concentration significantly inhibited P. aeruginosa and S. aureus while reducing the initial biofilm formation by 61% and 58%, respectively. In contrast, EE-L inhibited S. Typhimurium at a concentration of 12.5%-50% and P. aeruginosa at 25%-50%, with a strong preformed biofilm inhibition noticed for S. Typhimurium (70%). For the minimal contact time, EE-R superiorly inhibited P. aeruginosa (60 s) and S. aureus (120 s) on all contact surfaces, while EE-L needed 120 s to reduce P. aeruginosa and S. Typhimurium. These outcomes were comparable to sodium hypochlorite (NaOCl, 2.5%). The study's outcomes implicate the potential application of EE-R and EE-L as surface disinfectants against biofilm-forming bacteria, thus promoting safer food processing practices while minimizing environmental impacts.}, }
@article {pmid39755609, year = {2025}, author = {Shao, Y and Zhu, W and Liu, S and Zhang, K and Sun, Y and Liu, Y and Wen, T and Zou, Y and Zheng, Q}, title = {Cordycepin affects Streptococcus mutans biofilm and interferes with its metabolism.}, journal = {BMC oral health}, volume = {25}, number = {1}, pages = {25}, pmid = {39755609}, issn = {1472-6831}, support = {2019byyfyyq07//the First Affiliated Hospital of Bengbu Medical College Science Fund for Outstanding Young Scholars/ ; GXXT-2021-056//the University Synergy Innovation Program of Anhui Province/ ; KJ2020A0574//Key Science Research Project Funding of Education Department of Anhui Province/ ; }, mesh = {*Biofilms/drug effects ; *Streptococcus mutans/drug effects ; *Deoxyadenosines/pharmacology ; *Microbial Sensitivity Tests ; Humans ; Microscopy, Confocal ; Real-Time Polymerase Chain Reaction ; Keratinocytes/drug effects ; Metabolomics ; Anti-Bacterial Agents/pharmacology ; Biomass ; Tetrazolium Salts ; }, abstract = {BACKGROUND: Streptococcus mutans (S. mutans) contributes to caries. The biofilm formed by S. mutans exhibits greater resistance to drugs and host immune defenses than the planktonic form of the bacteria. The objective of this study was to evaluate the anti-biofilm effect of cordycepin from the perspective of metabolomics.<br><br>METHODS: The minimum inhibitory concentration (MIC) was determined to evaluate the antimicrobial effect of cordycepin on planktonic S. mutans. The 24-h biofilm was treated with 128&#xa0;&#xb5;g/mL of cordycepin for 10&#xa0;min at the 8- or 20-h time points. Biofilm biomass and metabolism were assessed using crystal violet and MTT assays and cordycepin cytotoxicity was evaluated in human oral keratinocytes (HOK) using CCK-8 assays. The live bacterial rate and the biofilm volume were assessed by confocal laser scanning microscopy. Metabolic changes in the biofilm collected at different times during with cordycepin were analyzed by metabolomics and verified by quantitative real-time PCR.<br><br>RESULTS: The results showed that treatment with 128&#xa0;&#xb5;g/mL cordycepin reduced both the biomass and metabolic activity of the biofilm without killing the bacteria, and cordycepin at this concentration showed good biocompatibility. Metabolomics analysis showed that differentially abundant metabolites following cordycepin treatment were mainly related to purine and nucleotide metabolism. After immediate treatment with cordycepin, genes related to purine and nucleotide metabolism were downregulated, and the levels of various metabolites changed significantly. However, the effect was reversible. After continuing culture for 4&#xa0;h, the changes in genes and most metabolites were reversed, although the levels of 2'-deoxyadenosine, 2'-deoxyinosine, and adenine remained significantly different.<br><br>CONCLUSIONS: Cordycepin has the effect of anti-biofilm of S. mutans, mainly related to purine and nucleotide metabolism.}, }
@article {pmid39753671, year = {2025}, author = {Vaidya, S and Saha, D and Rode, DKH and Torrens, G and Hansen, MF and Singh, PK and Jelli, E and Nosho, K and Jeckel, H and Göttig, S and Cava, F and Drescher, K}, title = {Bacteria use exogenous peptidoglycan as a danger signal to trigger biofilm formation.}, journal = {Nature microbiology}, volume = {10}, number = {1}, pages = {144-157}, pmid = {39753671}, issn = {2058-5276}, support = {TMCG-3_213801//Schweizerischer Nationalfonds zur F&#xf6;rderung der Wissenschaftlichen Forschung (Swiss National Science Foundation)/ ; 51NF40_180541//Schweizerischer Nationalfonds zur F&#xf6;rderung der Wissenschaftlichen Forschung (Swiss National Science Foundation)/ ; DR 982/5-1//Deutsche Forschungsgemeinschaft (German Research Foundation)/ ; DR 982/6-1//Deutsche Forschungsgemeinschaft (German Research Foundation)/ ; TARGET-Biofilms//Bundesministerium f&#xfc;r Bildung und Forschung (Federal Ministry of Education and Research)/ ; 716734//EC | EU Framework Programme for Research and Innovation H2020 | H2020 Priority Excellent Science | H2020 European Research Council (H2020 Excellent Science - European Research Council)/ ; IMPRS-Mic//Max-Planck-Gesellschaft (Max Planck Society)/ ; }, mesh = {*Biofilms/growth &amp; development/drug effects ; *Peptidoglycan/metabolism ; Gene Expression Regulation, Bacterial ; Gene Expression Profiling ; Signal Transduction ; Pseudomonas aeruginosa/genetics/physiology/metabolism ; Vibrio cholerae/genetics/physiology ; Bacteria/genetics/metabolism/growth &amp; development ; Bacteriophages/physiology/genetics ; Gram-Negative Bacteria/genetics/physiology/metabolism ; Staphylococcus aureus/physiology/genetics ; }, abstract = {For any organism, survival is enhanced by the ability to sense and respond to threats in advance. For bacteria, danger sensing among kin cells has been observed, but the presence or impacts of general danger signals are poorly understood. Here we show that different bacterial species use exogenous peptidoglycan fragments, which are released by nearby kin or non-kin cell lysis, as a general danger signal. Using microscopy and gene expression profiling of Vibrio cholerae, we find that even brief signal exposure results in a regulatory response that causes three-dimensional biofilm formation, which protects cells from a broad range of stresses, including bacteriophage predation. A diverse set of species (Pseudomonas aeruginosa, Acinetobacter baumannii, Staphylococcus aureus, Enterococcus faecalis) also respond to exogenous peptidoglycan by forming biofilms. As peptidoglycan from different Gram-negative and Gram-positive species triggered three-dimensional biofilm formation, we propose that this danger signal and danger response are conserved among bacteria.}, }
@article {pmid39747199, year = {2025}, author = {Vávrová, P and Janďourek, O and Diepoltová, A and Nachtigal, P and Konečná, K}, title = {The appropriate nutrient conditions for methicillin-resistant Staphylococcus aureus and Candida albicans dual-species biofilm formation in vitro.}, journal = {Scientific reports}, volume = {15}, number = {1}, pages = {183}, pmid = {39747199}, issn = {2045-2322}, support = {NU21-05-00482//Ministerstvo Zdravotnictv&#xed; Cesk&#xe9; Republiky/ ; SVV 260 664//Charles University/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Methicillin-Resistant Staphylococcus aureus/drug effects/physiology ; *Candida albicans/drug effects/physiology ; *Culture Media/pharmacology ; Humans ; Nutrients/metabolism ; Animals ; Sheep ; Microbial Sensitivity Tests ; Anti-Bacterial Agents/pharmacology ; }, abstract = {Polymicrobial biofilms, the reason for most chronic wound infections, play a significant role in increasing antibiotic resistance. The in vivo effectiveness of the new anti-biofilm therapy is conditioned by the profound evaluation using appropriate in vitro biofilm models. Since nutrient availability is crucial for in vitro biofilm formation, this study is focused on the impact of four selected cultivation media on the properties of methicillin-resistant Staphylococcus aureus and Candida albicans dual-species biofilms. To reflect the wound environment, Tryptic soy broth, RPMI 1640 with and without glucose, and Lubbock medium were supplemented with different amounts of host effector molecules present in human plasma or sheep red blood cells. The study demonstrates that the Lubbock medium provided the most appropriate amount of nutrients regarding the biomass structure and the highest degree of tolerance to selected antimicrobials with the evident contribution of the biofilm matrix. Our results allow the rational employment of nutrition conditions within methicillin-resistant Staphylococcus aureus and Candida albicans dual-species biofilm formation in vitro for preclinical research. Additionally, one of the potential targets of a complex antibiofilm strategy, carbohydrates, was revealed since they are prevailing molecules in the matrices regardless of the cultivation media.}, }
@article {pmid39745428, year = {2024}, author = {Cao, L and Mi, J and He, Y and Xuan, G and Wang, J and Li, M and Tong, Y}, title = {Quorum sensing inhibits phage infection by regulating biofilm formation of P. aeruginosa PAO1.}, journal = {Journal of virology}, volume = {}, number = {}, pages = {e0187224}, doi = {10.1128/jvi.01872-24}, pmid = {39745428}, issn = {1098-5514}, abstract = {UNLABELLED: Quorum sensing (QS) can regulate diverse critical phenotypic responses in Pseudomonas. aeruginosa (P. aeruginosa), enabling bacterial adaptation to external environmental fluctuations and optimizing population advantages. While there is emerging evidence of QS's involvement in influencing phage infections, our current understanding remains limited, necessitating further investigation. In this study, we isolated and characterized a novel phage designated as BUCT640 that infected P. aeruginosa PAO1. This phage belonged to class Caudoviricetes, genus Bruynoghevirus, with a podovirus morphology, and its adsorption was dependent on Psl polysaccharides, a repeating pentamer used to support biofilm structure. Leveraging phage BUCT640 as a model, we analyzed the role of both rhl QS and las QS in bacteria-phage interactions. Based on its distinctive plaque formation performances on different QS-related mutants, we investigated the variations of phage sensitivity to these strains and ultimately elucidated the mechanism underlying how QS inhibited phage infection to PAO1. Specifically, we unveiled that the las QS could inhibit phage adsorption, which is related to the thickness change caused by biofilm differentiation. Our findings suggest that the inhibition of QS may enhance phage infectivity, potentially facilitating advanced phage therapy combined with QS interference.<br><br>IMPORTANCE: Phage therapy is a powerful solution to combat drug-resistant pathogenic bacterial infections and has earned remarkable success in clinical treatment. However, recent insights underscore the potential impact of bacterial QS on phage infection dynamics. Here, we reported a unique phenomenon wherein QS, particularly in the las QS pathway, showed distinctive plaque formation behaviors by enlarging halos around plaques in mutant strains. In addition to this, we first elucidated the correlation between biofilm formation and phage infection. Notably, the las QS could inhibit phage adsorption, an effect closely related to biofilm thickness. Such research could be the evidence to steer bacterial QS toward favorable therapeutical outcomes. Therefore, our work can extend the comprehension of the interactions between bacteria and phages influenced by QS, thereby providing new perspectives on leveraging QS interference to enhance the efficacy of phage therapy for clinical applications.}, }
@article {pmid39745385, year = {2025}, author = {Kim, M-J and Mitchell, AP}, title = {Strain-limited biofilm regulation through the Brg1-Rme1 circuit in Candida albicans.}, journal = {mSphere}, volume = {10}, number = {1}, pages = {e0098024}, pmid = {39745385}, issn = {2379-5042}, support = {R01 AI146103/AI/NIAID NIH HHS/United States ; Distinguished Research Professorship//University of Georgia (UGA)/ ; 1R01AI146103//HHS | NIH | National Institute of Allergy and Infectious Diseases (NIAID)/ ; }, mesh = {*Candida albicans/genetics/physiology/pathogenicity ; *Biofilms/growth &amp; development ; *Transcription Factors/genetics/metabolism ; *Fungal Proteins/genetics/metabolism ; *Gene Expression Regulation, Fungal ; Hyphae/growth &amp; development/genetics ; Virulence ; Mutation ; }, abstract = {UNLABELLED: Prominent virulence traits of Candida albicans include its ability to produce filamentous hyphal cells and grow as a biofilm. These traits are under control of numerous transcription factors (TFs), including Brg1 and Rme1. In the reference strain SC5314, a brg1Δ/Δ mutant has reduced levels of biofilm/filament production; a brg1Δ/Δ rme1Δ/Δ double mutant has wild-type levels of biofilm/filament production. Here, we asked whether this suppression relationship is preserved in four additional strain backgrounds: P76067, P57055, P87, and P75010. These strains represent diverse clades and biofilm/filament production abilities. We find that a rme1Δ/Δ mutation restores biofilm/filament production in a brg1Δ/Δ mutant of P76067, but not in brg1Δ/Δ mutants of P57055, P87, and P75010. We speculate that variation in activities of two functionally related TFs, Nrg1, and Ume6, may cause the strain-limited impact of the rme1Δ/Δ mutation.<br><br>IMPORTANCE: Candida albicans is a widespread fungal pathogen. The regulatory circuitry underlying virulence traits is well studied in the reference strain background, but not in other clinical isolate backgrounds. Here, we describe a pronounced example of strain variation in the control of two prominent virulence traits, biofilm formation and filamentation.}, }
@article {pmid39745371, year = {2025}, author = {Pickens, CP and Wang, D and Pan, C and De León, KB}, title = {Absence of biofilm adhesin proteins changes surface attachment and cell strategy for Desulfovibrio vulgaris Hildenborough.}, journal = {Journal of bacteriology}, volume = {207}, number = {1}, pages = {e0037924}, pmid = {39745371}, issn = {1098-5530}, support = {//OU | College of Arts and Sciences, University of Oklahoma (CAS)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Desulfovibrio vulgaris/genetics/metabolism/physiology ; *Adhesins, Bacterial/metabolism/genetics ; *Bacterial Adhesion/physiology ; Bacterial Proteins/genetics/metabolism ; Gene Expression Regulation, Bacterial ; }, abstract = {UNLABELLED: Ubiquitous in nature, biofilms provide stability in a fluctuating environment and provide protection from stressors. Biofilms formed in industrial processes are exceedingly problematic and costly. While biofilms of sulfate-reducing bacteria in the environment are often beneficial because of their capacity to remove toxic metals from water, in industrial pipelines, these biofilms cause a major economic impact due to their involvement in metal and concrete corrosion. The mechanisms by which biofilms of sulfate-reducing bacteria form, however, are not well understood. Our previous work identified two proteins, named by their gene loci DVU1012 and DVU1545, as adhesins in the model sulfate-reducing bacterium, Desulfovibrio vulgaris Hildenborough. Both proteins are localized to the cell surface and the presence of at least one of the proteins, with either being sufficient, is necessary for biofilm formation to occur. In this study, differences in cell attachment and early biofilm formation in single deletion mutants of these adhesins were identified. Cells lacking DVU1012 had a different attachment strategy from wild-type (WT) and ΔDVU1545 cells, more often attaching as single cells than aggregates, which indicated that DVU1012 was more important for cell-to-cell attachment. ΔDVU1545 cells had increased cell attachment compared to WT cells when grown in static cultures. To date, comparisons of the D. vulgaris Hildenborough have been made to the large adhesion protein system in environmental pseudomonads. Yet, we and others have shown distinct mechanistic differences in the systems. We propose to name these proteins in D. vulgaris Hildenborough biofilm formation system to facilitate comparisons.<br><br>IMPORTANCE: Biofilms of sulfate-reducing bacteria contribute to biocorrosion, costing the United States hundreds of millions of dollars annually. In contrast, these biofilms can be used to bioremediate toxic heavy metals and to generate bioelectricity. As one of the most abundant groups of organisms on Earth, it is pertinent to better understand mechanistically how the biofilms of sulfate-reducing bacteria form so we may use this knowledge to help in efforts to mitigate biocorrosion, to promote bioremediation, and to produce clean energy. This study shows that the absence of either one of two biofilm adhesins impacts surface colonization by a sulfate-reducing bacterium, and that these two biofilm adhesins differ in their effect on cell attachment compared to other well-documented bacteria such as Pseudomonas species.}, }
@article {pmid39745211, year = {2024}, author = {Kizilyildirim, S and Köksal, F}, title = {[Examination of Capsule Genotypes, Antibiotic Susceptibility Profiles and Biofilm Forming Abilities of Group B Streptococcus Isolates Isolated from Pregnant Women].}, journal = {Mikrobiyoloji bulteni}, volume = {58}, number = {4}, pages = {380-392}, doi = {10.5578/mb.20249663}, pmid = {39745211}, issn = {0374-9096}, mesh = {Humans ; *Streptococcus agalactiae/drug effects/genetics/isolation &amp; purification/classification ; *Biofilms/drug effects ; Female ; Pregnancy ; *Streptococcal Infections/microbiology ; *Genotype ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; *Pregnancy Complications, Infectious/microbiology ; *Bacterial Capsules/genetics ; Erythromycin/pharmacology ; Drug Resistance, Bacterial/genetics ; Adult ; }, abstract = {Group B Streptococcus (GBS) or Streptococcus agalactiae is a pathogen that causes infections during pregnancy. The aim of this study was to investigate the antibiotic sensitivity profiles, capsule genotypes and biofilm forming capabilities of GBS isolates obtained from pregnant women . The study included 252 pregnant women who applied to Adana Gynecology and Children's Hospital between 2018 and 2023. The disk diffusion method was used to test antibiotic susceptibility. The multiplex polymerase chain reaction method was used to examine capsule genotypes (Ia-IX) and the genes responsible for resistance to erythromycin (ermB, ermTR, and mefA), clindamycin (linB) and tetracycline (tetM and tetO). The polystyrene microplate method was used to determine the presence of biofilm production. As a result of the study; It was observed that GBS isolates consisted of 44.8% III, 29% Ib, 20.6% Ia, 2.4% V, 1.6% IV, 1.2% II and 0.4% VI genotypes, respectively. All of the isolates were found be susceptible to cefotaxime, ampicillin, vancomycin, penicillin, and linezolid; however, 42.5% of the isolates were resistant to tetracycline, 33.3% to erythromycin and 24.2% to clindamycin. Erythromycin and tetracycline resistance genes were mostly detected in the capsule III genotype. It was observed that 6.3% of GBS isolates produced strong biofilm, 56% produced moderate biofilm and 37.7% produced weak biofilm. In the study, the distribution of capsule genotypes and changes in antibiotic susceptibility profiles of GBS isolates over the years were revealed. The results of this study contributed to the epidemiological studies on GBS infections by providing data.}, }
@article {pmid39745063, year = {2025}, author = {Palomares-Navarro, JJ and Bernal-Mercado, AT and González-Pérez, CJ and Martínez-Tellez, MA and Gonzalez-Aguilar, GA and Ortega-Ramirez, LA and Ayala-Zavala, JF}, title = {Inhibition of Salmonella Typhimurium biofilm and polysaccharide production via eugenol-glucosyltransferase interactions.}, journal = {Biofouling}, volume = {41}, number = {1}, pages = {113-130}, doi = {10.1080/08927014.2024.2446928}, pmid = {39745063}, issn = {1029-2454}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Eugenol/pharmacology ; *Salmonella typhimurium/drug effects ; *Glucosyltransferases/metabolism ; Polysaccharides, Bacterial/biosynthesis ; Microbial Sensitivity Tests ; Anti-Bacterial Agents/pharmacology ; Polysaccharides/pharmacology ; Bacterial Proteins ; }, abstract = {This study hypothesizes that eugenol, due to its structural properties, can inhibit glucosyltransferase activity, thereby reducing polysaccharide synthesis in Salmonella Typhimurium biofilms. It was found that eugenol exhibited minimum inhibitory and bactericidal concentrations of 0.6 mg mL[-1] and 0.8 mg mL[-1], respectively, against planktonic S. Typhimurium growth. It also demonstrated minimum biofilm eradication and inhibition concentrations of 1.8 mg mL[-1] and 0.7 mg mL[-1], respectively. At 0.3 mg mL[-1], eugenol reduced biofilm formation and affected polysaccharide production. Moreover, eugenol reduced glucosyltransferase activity. Computational analysis indicated strong interactions between eugenol and the enzyme's active site residues with affinity energy -8.5 kcal mol[-1]. Real-time PCR revealed a significant increase in bcsA gene expression in the presence of eugenol. These findings suggest that eugenol's ability to inhibit glucosyltransferase activity effectively reduces biofilm formation and polysaccharide content.}, }
@article {pmid39745056, year = {2025}, author = {Aragão, MGB and Aires, CP and Corona, SAM and He, X}, title = {Effects of epigallocatechin gallate on the development of matrix-rich Streptococcus mutans biofilm.}, journal = {Biofouling}, volume = {41}, number = {2}, pages = {171-180}, doi = {10.1080/08927014.2024.2446932}, pmid = {39745056}, issn = {1029-2454}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Streptococcus mutans/drug effects/physiology/growth &amp; development ; *Catechin/analogs &amp; derivatives/pharmacology ; *Microscopy, Confocal ; Polysaccharides, Bacterial/pharmacology ; Durapatite/chemistry ; Anti-Bacterial Agents/pharmacology ; Dental Caries/prevention &amp; control/microbiology ; }, abstract = {In this study, we evaluated the impact of Epigalocatechin-3-gallate (EGCG) on S. mutans biofilm development for 24 and 46 h using high-resolution confocal laser scanning microscopy. EGCG treatment led to the formation of interspaced exopolysaccharide (EPS)-microcolony complexes unevenly distributed on the surface of hydroxyapatite disc, forming a thinner and less complex biofilm structure with significantly reduced biomass, matrix volume, and thickness compared to the NaCl treated group (negative control). At 46 h, the biofilm of the EGCG-treatment group failed to form the bacterial-EPS superstructures which is characteristic of the biofilm in the negative control group. EGCG treatment seems to significantly delay biofilm development, with the 46 h biofilm in the EGCG treatment group resembling the negative control group at 24 h. EGCG topical treatments impaired S. mutans biofilm initial growth and maturation, suggesting its potential to be used as a preventive agent against dental caries.}, }
@article {pmid39744154, year = {2024}, author = {Liu, X and Li, J and Wu, R and Bai, L}, title = {Characterization of glycogen-related glycoside hydrolase glgX and glgB from Klebsiella pneumoniae and their roles in biofilm formation and virulence.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1507332}, pmid = {39744154}, issn = {2235-2988}, mesh = {*Biofilms/growth &amp; development ; *Klebsiella pneumoniae/genetics/pathogenicity/enzymology/metabolism/growth &amp; development ; Virulence ; *Glycogen/metabolism ; *Glycoside Hydrolases/metabolism/genetics ; Animals ; Temperature ; Hydrogen-Ion Concentration ; Klebsiella Infections/microbiology ; Mice ; Bacterial Proteins/genetics/metabolism ; Gene Deletion ; Virulence Factors/genetics/metabolism ; }, abstract = {Glycogen is a polymer used by bacteria to store excess glucose, playing a crucial role in bacterial growth, stress resistance, biofilm formation, and virulence. In bacteria, the glycoside hydrolase family 13 protein are involved in the synthesis and metabolism of glycogen, respectively. The absence of these enzymes leads to changes in bacterial glycogen content, thereby affecting the growth metabolism of the strain. To date, research on the roles of these glycogen-related glycoside hydrolase genes in the synthesis metabolism and bacterial phenotypes of Klebsiella pneumoniae has been limited. In this study, we characterized the glycogen-related glycoside hydrolase genes glgB and glgX of K. pneumoniae. We found that both enzymes exhibited significant degradation activity against glycogen substrates and were capable of degrading amylopectin, amylose, and pullulan. The optimal temperatures for GlgB and GlgX were both in the range of 35-40°C, with optimal pH values of 7.5 and 7.0, respectively, and they exhibited high stability at 37°C. Subsequently, we deleted the glgB and glgX genes in K. pneumoniae. The deletion of the glgB gene resulted in a decrease in the growth rate of the bacteria and defected glycogen synthesis. In contrast, the deletion of the glgX gene slightly accelerated the growth rate and led to continuous glycogen accumulation. In terms of biofilm formation and virulence, defects in glycogen synthesis impeded biofilm formation and virulence, while continuous glycogen accumulation did not affect biofilm formation but slightly increased virulence. In conclusion, the glgB and glgX genes are essential for the glycogen synthesis and metabolism in K. pneumoniae and further influence the biofilm formation capacity and virulence.}, }
@article {pmid39744121, year = {2024}, author = {Miao, Y and Shuang, W and Qianwei, Q and Xin, L and Wei, P and Hai, Y and Yonghui, Z and Xinbo, Y}, title = {Proteomic study of the inhibitory effects of tannic acid on MRSA biofilm.}, journal = {Frontiers in pharmacology}, volume = {15}, number = {}, pages = {1413669}, pmid = {39744121}, issn = {1663-9812}, abstract = {INTRODUCTION: The mechanism of tannic acid (TA) intervention on methicillin-resistant Staphylococcus aureus (MRSA, USA 300) biofilm formation was explored using proteomics.<br><br>METHODS: The minimum inhibitory concentration (MIC) of TA against the MRSA standard strain USA 300 was determined by two-fold serial dilution of the microbroth. The effects of TA were studied using crystal violet staining. The morphology of TA-treated USA 300 cells was observed by scanning electron microscopy and confocal laser scanning microscopy. Differentially expressed proteins (DEPs) were screened using proteomic and biological information analyses, and their transcriptional levels were verified using real-time quantitative polymerase chain reaction.<br><br>RESULTS: The MIC of TA was 0.625&#xa0;mg/mL, whereas 1/2 MIC (0.3125&#xa0;mg/mL) of TA significantly inhibited biofilm formation without affecting the bacterial growth (p < 0.01) and prevented the formation of a complete three-dimensional biofilm structure. Using 1/2 MIC of TA, 208 DEPs were identified, of which 127 were upregulated and 81 were downregulated. The transcriptional levels of the genes corresponding to five randomly selected DEPs (glnA, ribD, clpB, gap, and lukE) were consistent with the proteomics data (p < 0.05). Bioinformatic analysis showed that the changes in the MRSA strains after TA intervention primarily involved pyrimidine and purine metabolisms, arginine biosynthesis, and the citric acid cycle.<br><br>CONCLUSION: TA exerts an antibacterial effect on MRSA and can be used as a potential candidate for the development of anti-biofilm drugs, thereby laying a foundation for the treatment of MRSA biofilm-induced infections.}, }
@article {pmid39743153, year = {2025}, author = {Tai, ZS and Sun, Y and Dulatre Medriano, CA and Fu, Y and Jiang, Y and Lei, F and Liu, K and Yan, T and Xin Eve, LJ and Bae, SW and Hoon Elaine, QP and Chue, PW and Hui Lennis, SK and Wong, JJ and Ong, SL and Hu, J}, title = {Exploring water quality variations and biofilm growth in a drinking water distribution system via a biofilm annular reactor series system and predictive modelling of residual chlorine.}, journal = {Chemosphere}, volume = {371}, number = {}, pages = {144048}, doi = {10.1016/j.chemosphere.2024.144048}, pmid = {39743153}, issn = {1879-1298}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Chlorine/pharmacology/analysis ; *Drinking Water/microbiology/chemistry ; *Water Quality ; *Water Purification/methods ; Singapore ; Water Supply ; Water Pollutants, Chemical/analysis ; Bioreactors/microbiology ; Water Microbiology ; }, abstract = {The hydraulic conditions vary significantly across different segments of the drinking water distribution system (DWDS), leading to distinct variations in water quality throughout the system. Understanding these changes in water quality and biofilm development over time is crucial for enhancing drinking water management efficiency. This study focused on replicating the hydraulic conditions found in transmission and distribution pipelines within a specific pipeline path of the DWDS in Singapore using a biofilm annular reactor series system (BARSS). The BARSS experiment revealed that the total residual chlorine (TRC) concentration in water was greatly influenced by both flow velocity and the amount of biofilm present. TRC decay occurred more rapidly at higher flow velocity and was influenced by bacterial growth under fast flow conditions. Furthermore, UV254 levels in the water decreased with extended water age in the BARSS, due to the degradation of organic matters into smaller molecules. The study also found that higher TRC concentrations had a more pronounced inhibitory effect on biofilm formation and the proliferation of minor taxa. In the last part of the study, a predictive model for TRC concentration was developed using water quality parameters from preceding stages in the BARSS. This model demonstrated excellent prediction accuracy for TRC concentration, with a mean square error (MSE) of 0.0110 and R[2] of 0.9893.}, }
@article {pmid39743100, year = {2024}, author = {Sun, X and Chen, X and Wang, S and Gu, H and Bao, H and Ning, Z and Feng, X and Chen, Y}, title = {Oxygenous and biofilm-targeted nanosonosensitizer anchored with Pt nanozyme and antimicrobial peptide in the gelatin/sodium alginate hydrogel for infected diabetic wound healing.}, journal = {International journal of biological macromolecules}, volume = {}, number = {}, pages = {139356}, doi = {10.1016/j.ijbiomac.2024.139356}, pmid = {39743100}, issn = {1879-0003}, abstract = {Sonodynamic therapy is an emerging therapeutic approach for combating bacterial infections. However, the characteristics of hypoxia, high H2O2 microenvironment, and the formation of persistent biofilms in diabetic wound sites limit its efficacy in this field. To address these issues, we developed a multifunctional antibacterial hydrogel dressing PPCN@Pt-AMPs/HGel with the cross-linked gelatin and sodium alginate as the matrix, where the nanosonosensitizer PCN-224 was decorated with the oxygen-generating Pt nanoenzyme and further coupled with a biofilm-targeting antimicrobial peptide via an interacting polydopamine layer. This nano-composite hydrogel displayed improved mechanical properties as well as good biocompatibility and biodegradability. The catalase-like activity of the nanoparticles facilitated the ultrasound-induced generation of the singlet oxygen due to the catalytic decomposition of the H2O2 into O2. In vitro results showed that the hydrogel dressing exhibited excellent antimicrobial ability under low-intensity ultrasound stimulation, which could effectively inhibit the newly formed biofilm and eliminate the full-grown biofilms. In the infected diabetic wound of rats, PPCN@Pt-AMPs/HGel significantly enhanced the wound healing rate under low-intensity ultrasound stimulation and improved the regeneration outcomes by promoting granulation tissue formation, angiogenesis, and type III collagen deposition. In conclusion, our study provides a novel and effective antibacterial hydrogel dressing for sonodynamic treatment of diabetic wounds.}, }
@article {pmid39743066, year = {2024}, author = {Rath, S and Das, S}, title = {Stress response proteins within biofilm matrixome protect the cell membrane against heavy metals-induced oxidative damage in a marine bacterium Bacillus stercoris GST-03.}, journal = {International journal of biological macromolecules}, volume = {293}, number = {}, pages = {139397}, doi = {10.1016/j.ijbiomac.2024.139397}, pmid = {39743066}, issn = {1879-0003}, abstract = {Biofilm formation is a key adaptive response of marine bacteria towards stress conditions. The protective mechanisms of biofilm matrixome proteins against heavy metals (Pb and Cd) induced oxidative damage in the marine bacterium Bacillus stercoris GST-03 was investigated. Exposure to heavy metals resulted in significant changes in cell morphology, biofilm formation, and matrixome composition. Biofilm-encased cells showed lower oxidative damage. Biofilm matrixome protein exhibited major conformational changes, with 100 % α-helix turned to 62.33 % and 69.64 % of random coil under Pb and Cd stress, respectively. Fluorescence quenching kinetics revealed slow interactions between biofilm matrixome proteins and heavy metals (Kq values < 2.0 × 10[10]). Thermodynamic analysis showed negative ∆G (-16.02 kJ/mol for Pb and -17.45 kJ/mol for Cd) and binding dissociation constant (KD) (1530 ± 157 μM for Pb and 875 ± 97.4 μM for Cd), indicating a stronger binding affinity of biofilm matrixome to heavy metals. Pb stress led to overproduction of detoxification proteins (YnaI, KhtS, Bacillopeptidase F), competence and sporulation proteins (RapF, CSSF, XkdP), while Cd exposure leads to overproduction of proteins involved in protein misfolding repair (YlxX, cysteine-tRNA ligase, YacP), DNA repair (YfkN), and redox balance (cysteine synthase, YdiK). The findings highlight the resilience of B. stercoris GST-03 to heavy metal stress in biofilm mode.}, }
@article {pmid39742762, year = {2025}, author = {Chang, BZ and Huang, XL and Chen, DZ and Jin, RC and Yang, GF}, title = {How biofilm and granular sludge cope with dissolved oxygen exposure in anammox process: Performance, bioaccumulation characteristics and bacterial evolution.}, journal = {Journal of environmental management}, volume = {373}, number = {}, pages = {123986}, doi = {10.1016/j.jenvman.2024.123986}, pmid = {39742762}, issn = {1095-8630}, mesh = {*Biofilms ; *Sewage/microbiology ; *Oxygen/metabolism ; *Bioreactors ; *Oxidation-Reduction ; Nitrogen/metabolism ; Ammonium Compounds/metabolism ; Bacteria/metabolism ; Waste Disposal, Fluid/methods ; Biomass ; Extracellular Polymeric Substance Matrix/metabolism ; Anaerobiosis ; }, abstract = {In order to study the resistance mechanisms of biofilm and granular sludge to various dissolved oxygen (DO) exposures in anaerobic ammonium oxidation (anammox) process, a biofilm - granular sludge anammox reactor was established and operated. Experimental results showed that DO levels of ≤0.41 mg L[-1] hardly affected the total nitrogen removal efficiency (TNRE). Higher DO levels of 1.96-2.08 mg L[-1] promoted biomass disintegration and decreased specific anammox activity and extracellular polymeric substance (EPS) levels in granular sludge, but did not decrease EPS significantly in biofilm. The relative abundance of anammox genus Candidatus Kuenenia in granular sludge and biofilm decreased to 13.93% and 1.93%, respectively. NO3[-]-N was accumulated due to the increased NOB genus Nitrospira in granular sludge and biofilm. The inhibition effects of 1.96-2.08 mg L[-1] DO on anammox system were reversible, and the TNRE was quickly restored to (82.21 ± 2.39)% with AnAOB accumulation after removing aeration. This study provided theoretical support for the development of coupled biological nitrogen removal system based on anammox with other aerobic processes.}, }
@article {pmid39742531, year = {2024}, author = {Chougule, S and Basrani, S and Gavandi, T and Patil, S and Yankanchi, S and Jadhav, A and Karuppayil, SM}, title = {Zingerone effect against Candida albicans growth and biofilm production.}, journal = {Journal de mycologie medicale}, volume = {35}, number = {1}, pages = {101527}, doi = {10.1016/j.mycmed.2024.101527}, pmid = {39742531}, issn = {1773-0449}, abstract = {BACKGROUND: The increasing resistance of Candida albicans biofilms underscores the urgent need for effective antifungals. This study evaluated the efficacy of zingerone and elucidated its mode of action against C. albicans ATCC 90028 and clinical isolate C1.<br><br>EXPERIMENTAL PROCEDURE: Minimum inhibitory concentrations (MICs) of zingerone were determined using CLSI methods against planktonic cells, biofilm formation, and yeast-to-hyphal transition. The mode of action was investigated through fluorescent microscopy, ergosterol assays, cell cycle analysis, and RT-PCR for gene expression.<br><br>KEY RESULTS: Zingerone inhibited planktonic growth and biofilm formation at in C. albicans ATCC 90028 and clinical isolate C1 at 2 mg/mL 4 mg/mL and 1 mg/mL and 2 mg/mL respectively. Treatment with the MIC concentration caused significant cell cycle arrest at the G0/G1 phase, halting proliferation in both the strains. Propidium iodide Staining revealed compromised membrane integrity in both the strains. Also, acridine orange and ethidium bromide dual staining showed increased dead cell proportions in C. albicans ATCC 90028. RT-PCR studies showed downregulation of BCY1, PDE2, EFG1, and upregulation of negative regulators NRG1, TUP1 disrupting growth and virulence pathways. Zingerone induced elevated reactive oxygen species (ROS) levels, triggering apoptosis, evidenced by DNA fragmentation and upregulation of apoptotic markers. It also inhibited ergosterol synthesis in a concentration-dependent manner, crucial for membrane integrity. Importantly, zingerone exhibited minimal hemolytic activity. In an in vivo silkworm model, zingerone demonstrated significant antifungal efficacy, protecting silkworms from infection. It also modulated stress response genes, highlighting its multifaceted action.<br><br>CONCLUSIONS: In vitro and in vivo findings confirm the potent antifungal efficacy of zingerone against C. albicans ATCC 90028 and clinical isolate C1, suggesting its promising potential as a therapeutic agent that warrants further exploration.}, }
@article {pmid39742298, year = {2024}, author = {Fan, S and Qin, P and Lu, J and Wang, S and Zhang, J and Wang, Y and Cheng, A and Cao, Y and Ding, W and Zhang, W}, title = {Bioprospecting of culturable marine biofilm bacteria for novel antimicrobial peptides.}, journal = {iMeta}, volume = {3}, number = {6}, pages = {e244}, pmid = {39742298}, issn = {2770-596X}, abstract = {Antimicrobial peptides (AMPs) have become a viable source of novel antibiotics that are effective against human pathogenic bacteria. In this study, we construct a bank of culturable marine biofilm bacteria constituting 713 strains and their nearly complete genomes and predict AMPs using ribosome profiling and deep learning. Compared with previous approaches, ribosome profiling has improved the identification and validation of small open reading frames (sORFs) for AMP prediction. Among the 80,430 expressed sORFs, 341 are identified as candidate AMPs with high probability. Most potential AMPs have less than 40% similarity in their amino acid sequence compared to those listed in public databases. Furthermore, these AMPs are associated with bacterial groups that are not previously known to produce AMPs. Therefore, our deep learning model has acquired characteristics of unfamiliar AMPs. Chemical synthesis of 60 potential AMP sequences yields 54 compounds with antimicrobial activity, including potent inhibitory effects on various drug-resistant human pathogens. This study extends the range of AMP compounds by investigating marine biofilm microbiomes using a novel approach, accelerating AMP discovery.}, }
@article {pmid39742058, year = {2024}, author = {Sowmya, BR and Nayak, A and Kottrashetti, VS and Ingalagi, P and Harish, G}, title = {Determination of the antibiofilm property of aqueous extract of the Amorphophallus paeoniifolius on some early and late colonizers in an artificially synthesized dental biofilm - An in vitro study.}, journal = {Journal of Indian Society of Periodontology}, volume = {28}, number = {3}, pages = {325-331}, pmid = {39742058}, issn = {0972-124X}, abstract = {BACKGROUND: Mechanical therapy along with adjunctive therapy, using agents like chlorhexidine digluconate mouthwash helps to disrupt the plaque biofilm. Recently, herbs with medicinal value have been tested for their antimicrobial properties. The present study was designed to assess the anti-biofilm activity of Amorphophallus paeoniifolius against some periodontal pathogens in an artificially synthesized dental biofilm.<br><br>MATERIALS AND METHODS: The aqueous extract of A. paeoniifolius was constituted and its minimum inhibitory concentration (MIC) against standard strains of some periodontal pathogens was determined. A total of 21 biofilm samples were synthesized on extracted teeth and microtiter plates, and these were divided into two groups of 10 samples each. One group was treated with the predetermined MIC values of A. paeoniifolius, while the other group was treated with chlorhexidine. The anti-biofilm activity of both compounds was assessed by calculating colony-forming units (CFUs) for the extracted teeth and optical density (OD) values for the microtiter plates.<br><br>RESULTS: The mean CFU at baseline was 55,000/&#x3bc;l while posttreatment with chlorhexidine digluconate and aqueous extract of A. paeoniifolius was 23,280 &#xb1; 5274.00 and 28,560 &#xb1; 4509.545/&#x3bc;l, respectively. The mean OD value (at 595 nm) posttreatment with chlorhexidine digluconate was 0.9876 &#xb1; 0.49179 and A. paeoniifolius was 1.4990 &#xb1; 0.37851. Results indicate that the aqueous extract of A. paeoniifolius showed an inhibitory effect on biofilm obtained on microtiter plates and the one constituted on extracted teeth.<br><br>CONCLUSION: Anti-biofilm activity of aqueous extract of A. paeoniifolius was appreciable and also comparable to that of chlorhexidine digluconate, both on extracted teeth and microtiter plates.}, }
@article {pmid39741867, year = {2024}, author = {de Araújo, LGS and Rodrigues, THS and Rates, ERD and Alencar, LMR and Rosa, MF and Ponte Rocha, MV}, title = {Production of Cellulose Nanoparticles from Cashew Apple Bagasse by Sequential Enzymatic Hydrolysis with an Ultrasonic Process and Its Application in Biofilm Packaging.}, journal = {ACS omega}, volume = {9}, number = {51}, pages = {50671-50684}, pmid = {39741867}, issn = {2470-1343}, abstract = {Cellulose nanostructures obtained from lignocellulosic biomass via enzymatic processes may offer advantages in terms of material properties and processing sustainability. Thus, in this study, cellulose nanoparticles with a spherical morphology were produced through the enzymatic hydrolysis of cashew apple bagasse (CAB). CAB was previously subjected to alkaline and acid-alkali pretreatment, and the pretreated solids were labeled as CAB-PTA and CAB-PT-HA, respectively. The enzymatic hydrolysis was carried out using two different enzymatic loadings (7.5 and 12 FPU/gcellulose) of the Trichoderma reesei cellulase complex, and the formation of nanostructures occurred only at 7.5 FPU/gcellulose. The results indicated the production of nanocellulose using only CAB-PT-HA as the precursor, obtaining nanosphere structures with a yield of 65.1 ± 2.9% and a diameter range of 57.26-220.66 nm. The nanocellulose showed good thermal and colloidal stability and was subsequently used for biofilm production. Biofilms were prepared using different percentages of nanocellulose (5 and 7% w/v), and they showed a greater water retention capacity and higher biodegradability compared to the control film, indicating potential for application in food packaging and cosmetic masks. Thus, it highlights the potential for developing new biodegradable plastics incorporated with nanocellulose obtained from CAB through a more sustainable process.}, }
@article {pmid39739329, year = {2024}, author = {Nguyen, VT and Le, TN and Huynh, DD and Le, VA and Do, QH and Vo, TD}, title = {Maximizing nutrient removal: unveiling the influence of biomass retention time in revolving algae biofilm reactor.}, journal = {Environmental technology}, volume = {}, number = {}, pages = {1-11}, doi = {10.1080/09593330.2024.2445325}, pmid = {39739329}, issn = {1479-487X}, abstract = {This study introduces a novel Revolving Algae Biofilm reactor for synthetic wastewater treatment, examining the influence of various biomass retention times (BRTs) on nutrient removal performance. The study reveals complex interactions between microalgae and bacteria, emphasizing their symbiotic functions in oxygen provision, nutrient absorption, and floc creation. This research contributes to the advancement of sustainable wastewater treatment methods, showing promise for large-scale nutrient removal in industrial settings. The biomass retention time of 3 days (BRT-3) emerges as the most suitable condition for efficient nutrient removal. Specifically, in the BRT-3 period, the reactor can remove up to 97% of NH4-N, 94% of total phosphorus, and 92% of COD. NH4-N was also effectively assimilated to NO2-N and NO3-N, underscoring the efficiency of the nitrification process. While BRT-7 exhibits a noteworthy algae growth rate when it reaches the maximum rate of 3 mg/L.day. Continual investigation into the interplay between microalgae and bacteria is essential for enhancing system efficiency in future wastewater treatment applications.}, }
@article {pmid39739165, year = {2024}, author = {Pathoor, NN and Ganesh, PS and Anshad, AR and Gopal, RK and Ponmalar, EM and Suvaithenamudhan, S and Rudrapathy, P and Shankar, EM}, title = {3-Hydroxybenzoic acid inhibits the virulence attributes and disrupts biofilm production in clinical isolates of Acinetobacter baumannii.}, journal = {European journal of clinical microbiology &amp; infectious diseases : official publication of the European Society of Clinical Microbiology}, volume = {}, number = {}, pages = {}, pmid = {39739165}, issn = {1435-4373}, abstract = {PURPOSE: Acinetobacter baumannii (A. baumannii) is an emerging global public health threat owing to its ability to form biofilms. Here, we evaluated 3-hydroxybenzoic acid (3-HBA), a promising organic compound, for its ability to disrupt biofilm formation and virulence attributes in clinical isolates of A. baumannii.<br><br>MATERIALS AND METHODS: The effect of 3-HBA on A. baumannii was assessed by determining the minimum inhibitory concentration (MIC) and certain other in vitro investigations viz., extracellular polymeric substance (EPS) estimation, crystal violet staining assay, motility assay, and the hydrogen peroxide (H2O2) assay to examine its impact on bacterial virulence. Biofilm formation was also evaluated at the air-liquid interface.&#xa0;In situ visualization investigations were employed to confirm biofilm dispersion at the lowest effective concentration. The cytotoxic effects of 3-HBA on MCF-7 cells were investigated using the MTT assay.<br><br>RESULTS: At a sub-inhibitory concentration of 0.078&#xa0;mg/mL, 3-HBA reduced biofilm formation in A. baumannii LSAB-04 and A. baumannii LSAB-06 by 61.22% and 59.21%, respectively, and decreased EPS production by 64% in LSAB-04 and 58.31% in LSAB-06. Microscopic examination confirmed significant biofilm dispersion. 3-HBA also significantly impaired swarming motility and increased their sensitivity to H2O2. The MTT assay showed a dose-dependent decrease in MCF-7 cell viability (43.67%) at a concentration of 0.078&#xa0;mg/mL.<br><br>CONCLUSION: Our findings underscore the likely role of 3-HBA as a promising A. baumannii biofilm-disrupting agent. Further, by downplaying against the&#xa0;virulence factors of A. baumannii, 3-HBA could be a compelling alternative to conventional antibiotics that however&#xa0;requires to be investigated.}, }
@article {pmid39739119, year = {2024}, author = {Li, J and Wang, J and Wu, J and Wang, X}, title = {Matrix-producing cells' orientation order facilitates Bacillus subtilis biofilm self-healing.}, journal = {Archives of microbiology}, volume = {207}, number = {1}, pages = {19}, pmid = {39739119}, issn = {1432-072X}, support = {12372321 and 11972074//National Natural Science Foundation of China/ ; }, mesh = {*Bacillus subtilis/physiology/metabolism/genetics ; *Biofilms/growth &amp; development ; }, abstract = {During the self-healing process of Bacillus subtilis biofilms on a solid MSgg substrate, large-scale ordered clusters emerge within the biofilm, providing an invasive advantages. To investigate the self-healing mechanism, an agent-based model is employed to simulate the self-healing processes of biofilms at two ages. The study reveals that a uniform cell distribution facilitates the healing of biofilm incisions. The nutrient diffusion rate within the biofilm and the elastic modulus (comprising cell and EPS) play a dominant role in the healing of circumferential incisions, while the diffusion rate outside the biofilm governs the healing of radial and penetrating incisions. These influencing factors can adjust cellular ordering, providing valuable insights for controlling the self-healing of Bacillus subtilis biofilms.}, }
@article {pmid39737751, year = {2025}, author = {Benny, AT and Radhakrishnan, EK}, title = {Assessing the antibiofilm activity of flavonol esters against Pseudomonas aeruginosa PAO1 biofilm: an in vitro, molecular docking, and molecular dynamics study.}, journal = {Journal of biomolecular structure &amp; dynamics}, volume = {43}, number = {2}, pages = {813-829}, doi = {10.1080/07391102.2023.2283811}, pmid = {39737751}, issn = {1538-0254}, mesh = {*Biofilms/drug effects ; *Pseudomonas aeruginosa/drug effects ; *Molecular Dynamics Simulation ; *Flavonols/pharmacology/chemistry ; *Molecular Docking Simulation ; *Esters/chemistry/pharmacology ; *Anti-Bacterial Agents/pharmacology/chemistry ; Microbial Sensitivity Tests ; Virulence Factors/metabolism ; Bacterial Proteins/metabolism/chemistry ; Hydrophobic and Hydrophilic Interactions ; Glycolipids/chemistry/pharmacology/metabolism ; Quorum Sensing/drug effects ; Pyocyanine/metabolism ; Gene Expression Regulation, Bacterial/drug effects ; }, abstract = {Pseudomonas aeruginosa is one of the opportunistic pathogens that may cause serious health problems and can produce several virulence factors, which are responsible for various infections, particularly in immunocompromised patients. They are responsible for producing infections on indwelling medical devices by attaching on to them and forming a biofilm. Antibiofilm, antivirulence, and gene expression studies of P. aeruginosa biofilm treated with esters of flavonols were evaluated. Pyocyanin, cell surface hydrophobicity, LasA protease estimation, rhamnolipid estimation, and pyoverdine estimation were performed to evaluate the antivirulence activities of the test compounds against P. aeruginosa. Previous studies on the antivirulence activity of flavonoids against P. aeruginosa demonstrate that even if they can inhibit bacterial growth, relatively high concentrations of the compound are generally required for the inhibition of virulence factors. The esters showed more than 40% inhibition in all the tested virulence factors at their sub minimum inhibitory concentration. The gene expression studies of selected esters toward lasB and rhlA genes show downregulation of rhlA which suggests the inhibition in biofilm formation through rhamnolipid inhibition, quorum sensing inhibition, or biofilm formation inhibition.Communicated by Ramaswamy H. Sarma.}, }
@article {pmid39736993, year = {2024}, author = {Migliaccio, A and Stabile, M and Triassi, M and Dé, E and De Gregorio, E and Zarrilli, R}, title = {Inhibition of biofilm formation and preformed biofilm in Acinetobacter baumannii by resveratrol, chlorhexidine and benzalkonium: modulation of efflux pump activity.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1494772}, pmid = {39736993}, issn = {1664-302X}, abstract = {INTRODUCTION: The persistence of Acinetobacter baumannii in the contaminated environment is sustained by tolerance to biocides and ability to growth as biofilm. The aim of the study was to analyze the susceptibility of A. baumannii biofilms to chlorhexidine (CHX) and benzalkonium (BZK) biocides and the ability of natural monomeric stilbenoid resveratrol (RV) to modulate the phenomenon.<br><br>METHODS: Biofilm formation and preformed biofilm were tested by Crystal violet and tetrazolium salt reduction assay, respectively. Analysis of efflux pump (EP) expression during biofilm growth was performed by Real-time RT-PCR assays.<br><br>RESULTS: CHX and BZK at &#xbc; and &#xbd; MICs alone or in combination inhibited biofilm growth of A. baumannii ATCC 19606, 4190, and 3909 strains. RV at 32&#x202f;mg/L and CHX and BZK at &#xbc; or &#xbd; MICs showed a synergistic effect and completely inhibited biofilm formation in all A. baumannii strains. Similarly, RV at 32&#x202f;mg/L and CHX and BZK at &#xbd; MIC significantly inhibited air-liquid biofilm formation of A. baumannii ATCC 19606, 4190 and 3909 strains. The inactivation of AdeB and AdeJ RND EPs in A. baumannii ATCC19606 increased the susceptibility to CHX and BZK alone or in the presence of 32&#x202f;mg/L RV. Concordantly, carbonyl cyanide m-chlorophenylhydrazine (CCCP) increased the susceptibility to CHX, BZK and RV and dose-dependently inhibited biofilm formation in A. baumannii ATCC 19606, 4190 and 3909 strains. RV at 32&#x202f;mg/L inhibited basal and CHX-induced EP genes expression, while increased EP gene expression in the presence of BZK during A. baumannii ATCC19606 biofilm growth. In addition, CHX and BZK alone or in combination dose-dependently reduced preformed biofilm of all A. baumannii strains. The combination of RV with CHX and BZK additively decreased minimal biofilm eradicating concentrations in A. baumannii strains.<br><br>CONCLUSION: These results demonstrate that: (i) CHX and BZK alone or in the presence of RV inhibit biofilm growth and preformed biofilm in A. baumannii; (ii) tolerance to CHX and BZK during biofilm growth is dependent on the activation of AdeB and AdeJ EPs; and (iii) the inhibitory effect of RV on biofilm growth is mediated by the inhibition of EP genes expression in A. baumannii.}, }
@article {pmid39736437, year = {2025}, author = {Zhai, T and Zhang, L and Zhang, F and Su, X and Chen, P and Xing, Z and Liu, H and Zhao, T}, title = {Characteristics of biofilm layer in a bio-doubling reactor and their impact on aerobic denitrifying bacteria enrichment.}, journal = {Environmental research}, volume = {267}, number = {}, pages = {120730}, doi = {10.1016/j.envres.2024.120730}, pmid = {39736437}, issn = {1096-0953}, mesh = {*Biofilms/growth &amp; development ; *Denitrification ; *Bioreactors/microbiology ; Wastewater/microbiology ; Waste Disposal, Fluid/methods ; Aerobiosis ; Bacteria, Aerobic/metabolism ; Nitrogen/metabolism ; }, abstract = {Microbial loss significantly affects wastewater treatment efficiency. This study simulated the inoculation area of a self-developed biological doubling reactor (BDR) to evaluate the retention efficiency of seven different fillers for aerobic denitrifying bacteria. Over 90 days of continuous operation, the porous filler R3 demonstrated excellent performance, with OD600 values consistently exceeding 1.0 and minimal fluctuation. On day 90, the seed liquid amplified with R3 achieved removal efficiencies of 100% for ammonia nitrogen, 97.75% for total nitrogen, and 96.4% for chemical oxygen demand, outperforming other fillers. Scanning electron microscopy and microscopic analysis revealed that R3's large large specific surface area and volume formed a unique meshed biofilm structure, enhancing oxygen and nutrient transport while minimizing detachment. This promoted effective enrichment and retention of aerobic denitrifying bacteria. Microbial diversity analysis confirmed that Acinetobacter, a key genus involved in aerobic denitrification, dominated the network biofilm on R3, accounting for an average of 35.63%. while granular fillers, due to oxygen limitation, promoted the growth of anaerobic ammonium-oxidizing Alcaligenes. The use of BDR-enhanced MBBR for treating synthetic wastewater resulted in a 29.6% increase in TN removal efficiency, with stable system operation. The use of porous fillers with a high specific volume supports stable biofilm formation and consistent seed liquid output, providing a viable solution to microbial loss in wastewater treatment processes.}, }
@article {pmid39736338, year = {2025}, author = {Xia, L and Wu, B and Cui, X and Ran, T and Li, Q and Zhou, Y}, title = {Machine learning-based prediction of non-aeration linear alkylbenzene sulfonate mineralization in an oxygenic microalgal-bacteria biofilm.}, journal = {Bioresource technology}, volume = {419}, number = {}, pages = {132028}, doi = {10.1016/j.biortech.2024.132028}, pmid = {39736338}, issn = {1873-2976}, mesh = {*Biofilms ; *Microalgae/metabolism ; *Alkanesulfonic Acids ; *Oxygen/metabolism ; Bacteria/metabolism ; Machine Learning ; Bioreactors ; Support Vector Machine ; Water Pollutants, Chemical ; Water Purification/methods ; Biodegradation, Environmental ; }, abstract = {Microalgal-bacteria biofilm shows great potential in low-cost greywater treatment. Accurately predicting treated greywater quality is of great significance for water reuse. In this work, machine learning models were developed for simulating and predicting linear alkylbenzene sulfonate (LAS) removal using 152-days collected data from a battled oxygenic microalgal-bacteria biofilm reactor (MBBfR). By using nine variables including influent LAS, hydraulic retention time (HRT), biofilm density and thickness, specific oxygen production and consumption rates, microalgae and bacteria concentrations, and dissolved oxygen (DO), the support vector machine (SVM) model enabled the accurate LAS removal prediction (training set: R[2] = 0.995, (root mean square error, RMSE) = 0.076, (mean absolute error, MAE) = 0.069; testing set: R[2] = 0.961, RMSE = 0.251, MAE = 0.153). SVM can be also successfully applied for MBBfR operation optimization (HRT = 4.28 h, DO = 0.25 mg/L) that achieving accurate prediction of LAS mineralization.}, }
@article {pmid39736219, year = {2025}, author = {Kong, L and Hu, X and Xia, D and Wu, J and Zhao, Y and Guo, H and Zhang, S and Qin, C and Wang, Y and Li, L and Su, Z and Zhu, C and Xu, S}, title = {Janus PEGylated CuS-engineered Lactobacillus casei combats biofilm infections via metabolic interference and innate immunomodulation.}, journal = {Biomaterials}, volume = {317}, number = {}, pages = {123060}, doi = {10.1016/j.biomaterials.2024.123060}, pmid = {39736219}, issn = {1878-5905}, mesh = {*Lacticaseibacillus casei ; *Biofilms/drug effects ; Animals ; Mice ; Polyethylene Glycols/chemistry ; RAW 264.7 Cells ; Immunomodulation/drug effects ; Copper/chemistry/pharmacology ; Immunity, Innate ; Hydrogen Peroxide/metabolism ; Nanoparticles/chemistry ; Macrophages/metabolism/drug effects ; }, abstract = {Bacterial implant-associated infections predominantly contribute to the failure of prosthesis implantation. The local biofilm microenvironment (BME), characterized by its hyperacidic condition and high hydrogen peroxide (H2O2) level, inhibits the host's immune response, thereby facilitating recurrent infections. Here, a Janus PEGylated CuS nanoparticle (CuPen) armed engineered Lactobacillus casei (L. casei) denoted as LC@CuPen, is proposed to interfere with bacterial metabolism and arouse macrophage antibiofilm function. Once LC@CuPen reached the BME, NIR irradiation-activated mild heat damages L. casei and biofilm structure. Meanwhile, the BME-responsive LC@CuPen can catalyze local H2O2 to produce toxic •OH, whereas in normal tissues, the effect of •OH production is greatly reduced due to the higher pH and lower H2O2 concentration. The released bacteriocin from damaged L. casei can destroy the bacterial membrane to enhance the penetration of •OH into damaged biofilm. Excessive •OH interferes with normal bacterial metabolism, resulting in reduced resistance of bacteria to heat stress. Finally, under the action of mild heat treatment, the bacterial biofilm lysed and died. Furthermore, the pathogen-associated molecular patterns (PAMPs) in LC@CuPen can induce M1 polarization of macrophages through NF-κB pathway and promote the release of inflammatory factors. Inflammatory factors enhance the migration of macrophages to the site of infection and phagocytose bacteria, thereby inhibiting the recurrence of infection. Generally, this engineered L. casei program presents a novel perspective for the treatment of bacterial implant-associated infections and serves as a valuable reference for future clinical applications of engineered probiotics.}, }
@article {pmid39734766, year = {2024}, author = {Nazari, M and Hemmati, J and Asghari, B}, title = {Comprehensive Analysis of Virulence Genes, Antibiotic Resistance, Biofilm Formation, and Sequence Types in Clinical Isolates of Klebsiella pneumoniae.}, journal = {The Canadian journal of infectious diseases &amp; medical microbiology = Journal canadien des maladies infectieuses et de la microbiologie medicale}, volume = {2024}, number = {}, pages = {1403019}, pmid = {39734766}, issn = {1712-9532}, abstract = {Background: The rise in multidrug-resistant pathogens poses a formidable challenge in treating hospital-acquired infections, particularly those caused by Klebsiella pneumoniae. Biofilm formation is a critical factor contributing to antibiotic resistance, enhancing bacterial adherence and persistence. K. pneumoniae strains vary in virulence factors, influencing their pathogenicity and resistance profiles. This study aimed to comprehensively analyze virulence factors, antibiotic resistance patterns, and biofilm formation in clinical isolates of K. pneumoniae from Hamadan hospitals. Moreover, the study explored the molecular epidemiological relationships among isolates using multilocus sequence typing (MLST) to uncover the genetic diversity associated with resistance and virulence. Materials and Methods: Between December 2022 and April 2024, 402 K. pneumoniae isolates were collected from clinical samples, including urine, tracheal aspirates, blood, wounds, and abscesses, in teaching hospitals in Hamadan. Initial culturing was performed on blood agar and MacConkey agar, and isolates were identified using biochemical tests. Antimicrobial susceptibility testing followed CLSI, employing the Kirby-Bauer disk diffusion method with 10 antibiotics. Biofilm formation was assessed using the microtiter plate method, and virulence genes were detected by PCR. MLST analysis was conducted on 10 selected isolates based on their virulence gene profiles and resistance patterns. Result: Of the 456 clinical isolates analyzed, 402 (88.15%) were identified as K. pneumoniae, predominantly isolated from tracheal samples (251/402, 62.44%), followed by urine (105/402, 26.12%), blood (30/402, 7.46%), wounds (15/402, 3.73%), and abscesses (1/402, 0.25%). Antibiotic resistance rates revealed high resistance to cefepime (356/402, 88.55%), imipenem (345/402, 85.82%), and ceftazidime (305/402, 75.87%), while resistance to amikacin (165/402, 41.04%) and piperacillin-tazobactam (75/402, 18.65%) was comparatively lower. Biofilm formation varied among the isolates, with 17/402 (4.22%) forming strong biofilms, 104/402 (25.87%) moderate biofilms, 180/402 (44.78%) weak biofilms, and 101/402 (25.12%) showing no biofilm production. Virulence gene analysis indicated high prevalence rates for mrkD (396/402, 98.50%), fimH1 (351/402, 87.31%), and entB (402/402, 100%), while genes like irp-1 (151/402, 37.56%) and irp-2 (136/402, 33.83%) were less common, and hylA and cnf-1 were absent. MLST analysis of 10 selected isolates identified sequence types ST147 (5/10, 50%), ST11 (3/10, 30%), and ST15 (2/10, 20%). Conclusion: K. pneumoniae demonstrates notable biofilm-associated antibiotic resistance, supported by a significant association with XDR strains, along with a diverse array of virulence gene profiles. The study underscores the importance of understanding molecular epidemiology for effective management of hospital infections, emphasizing the need for targeted surveillance and infection control measures.}, }
@article {pmid39734628, year = {2024}, author = {Li, H and Staxäng, K and Ladak, HM and Agrawal, S and Rask-Andersen, H}, title = {Middle ear biofilm and sudden deafness - a light and transmission electron microscopy study.}, journal = {Frontiers in neurology}, volume = {15}, number = {}, pages = {1495893}, pmid = {39734628}, issn = {1664-2295}, abstract = {BACKGROUND: There still exists controversy about whether the healthy human middle ear mucosa is sterile or if it may harbor a diverse microbiome. Considering the delicacy of the human round window membrane (RWM), different mechanisms may exist for avoiding inner ear pathogen invasion causing sensorineural deafness. We re-analyzed archival human RWMs using light and transmission electron microscopy after decalcification to determine if bacteria are present in clinically normal human middle ears. We also searched for the presence of inborn immune defensive mechanisms within the round window niche (RWN), as previously reported in non-human primate ears.<br><br>MATERIALS AND METHODS: Five round window niches, removed and directly fixed at transcochlear petroclival meningioma surgery, were re-investigated after ethical permission using light and transmission electron microscopy. The morphology of the RWM, including its bony attachment and pseudomembrane outline, was analyzed. Moreover, 64 human temporal bones were investigated using synchrotron phase-contrast imaging (SR-PCI) aiming to identify potentially "hidden" spaces, including the RWN potentially harboring infectious material.<br><br>RESULTS: Histologic evidence of free-living bacteria and biofilm was found in 40% of RWNs in seemingly "healthy" middle ears. The RWM in these ears was pathologically changed with repealed epithelial and intercellular junctional integrity. Putative membranous defense machinery consisted of a lymphatic drainage system together with free phagocytic cells seemingly serving to protect the inner ear from alleged pathogens. Synchrotron analyses showed that a pseudomembrane was present in the human round window niche (RWN) in 80% of the specimens, of which 20% were complete. In 3%, the RWN contained dense tissue or serous fluid plugs partly obstructing the RWN. Infralabyrinthic clefts and tympanomeningeal fissures (Hyrtl's fissure) were occasionally enclosed by delicate membranes near the round window. These may represent predilection sites for "hidden" infections potentially endangering inner ear function, particularly in connection with round window surgery.<br><br>CONCLUSION: Considering the fragility of the normal human RWM, we speculate that occult colonies of biofilm may be a factor in surgeries involving the RWM, sensorineural hearing loss, and hearing preservation/fibrosis following cochlear implantation, and more controversially in hidden perilymph leaks causing sudden deafness and labyrinthine pathology.}, }
@article {pmid39734361, year = {2024}, author = {Lange, A and Kutwin, M and Zawadzka, K and Ostrowska, A and Strojny-Cieślak, B and Nasiłowska, B and Bombalska, A and Jaworski, S}, title = {Impaired Biofilm Development on Graphene Oxide-Metal Nanoparticle Composites.}, journal = {Nanotechnology, science and applications}, volume = {17}, number = {}, pages = {303-320}, pmid = {39734361}, issn = {1177-8903}, abstract = {PURPOSE: Biofilms are one of the main threats related to bacteria. Owing to their complex structure, in which bacteria are embedded in the extracellular matrix, they are extremely challenging to eradicate, especially since they can inhabit both biotic and abiotic surfaces. This study aimed to create an effective antibiofilm nanofilm based on graphene oxide-metal nanoparticles (GOM-NPs).<br><br>METHODS: To create nanofilms, physicochemical analysis was performed, including zeta potential (Zp) (and the nanocomposites stability in time) and size distribution measurements, scanning transmission electron microscopy (STEM), energy dispersive X-ray analysis (EDX), and atomic force microscopy (AFM) of the nanofilm surfaces. During biological analysis, reactive oxygen species (ROS) and antioxidant capacity were measured in planktonic cells treated with the nanocomposites. Thereafter, biofilm formation was checked via crystal violet staining, biofilm thickness was assessed by confocal microscopy using double fluorescent staining, and biofilm structure was analyzed by scanning electron microscopy.<br><br>RESULTS: The results showed that two of the three nanocomposites were effective in reducing biofilm formation (GOAg and GOZnO), although the nanofilms were characterized by the roughest surface, indicating that high surface roughness is unfavorable for biofilm formation by the tested bacterial species (Staphylococcus aureus (ATCC 25923), Salmonella enterica (ATCC 13076), Pseudomonas aeruginosa (ATCC 27853)).<br><br>CONCLUSION: The performed analysis indicated that graphene oxide may be a platform for metal nanoparticles that enhances their properties (eg colloidal stability, which is maintained over time). Nanocomposites based on graphene oxide with silver nanoparticles and other types of nanocomposites with zinc oxide were effective against biofilms, contributing to changes throughout the biofilm structure, causing a significant reduction in the thickness of the structure, and affecting cell distribution. A nanocomposite consisting of graphene oxide with copper nanoparticles inhibited the biofilm, but to a lesser extent.}, }
@article {pmid39734057, year = {2025}, author = {Soulaimani, B and Abbad, I and Dumas, E and Gharsallaoui, A}, title = {Enhanced antimicrobial and biofilm disruption efficacy of the encapsulated Thymus pallidus and Lavandula stoechas essential oils and their mixture: A synergistic approach.}, journal = {International journal of pharmaceutics}, volume = {670}, number = {}, pages = {125144}, doi = {10.1016/j.ijpharm.2024.125144}, pmid = {39734057}, issn = {1873-3476}, mesh = {*Biofilms/drug effects ; *Oils, Volatile/pharmacology/chemistry ; *Thymus Plant/chemistry ; *Lavandula/chemistry ; *Microbial Sensitivity Tests ; Drug Synergism ; Anti-Infective Agents/pharmacology/chemistry ; Particle Size ; Drug Compounding/methods ; Capsules ; Anti-Bacterial Agents/pharmacology/chemistry ; }, abstract = {The antimicrobial and antibiofilm properties of plant essential oils (EOs) have aroused significant interest for their potential as effective alternatives or supplements in combating microbial infections and biofilm-associated challenges. For these applications, EOs must be encapsulated to overcome some key technical limitations, including high volatility, poor stability, and low solubility. This study aimed to develop microencapsulated EOs derived from two valuable Moroccan medicinal plants, Lavandula stoechas L. and Thymus pallidus Batt., both individually and in combination, using the spray drying method. The antimicrobial and antibiofilm effects of these encapsulated EOs were evaluated against various pathogenic microorganisms using microdilution and crystal violet assays. Key physico-chemical characteristics of the EO microcapsules, including optimal particle size, favorable zeta potential, low water content, and high encapsulation yield and efficiency were observed, indicating strong stability and effective encapsulation. The major chemical compounds identified in the studied EOs were thymol (26.72 %), γ-terpinene (23.26 %), and p-cymene (19.07 %) in T. pallidus EO; and camphor (47.67 %), fenchone (20.78 %), and 1.8-cineole (12.17 %) in L. stoechas EO. The results from antimicrobial assays demonstrated that the encapsulated T. pallidus EO exhibited stronger inhibitory and microbicidal effects against all tested strains, with MIC and MMC values ranging from 0.312 mg/mL to 2.50 mg/mL. The encapsulated EOs combination demonstrated interesting antimicrobial effect, with varying type of interactions depending on the target microorganisms. Additionally, the antibiofilm activity of the microencapsulated EOs combination, evaluated against Staphylococcus aureus, Klebsiella pneumoniae and Bacillus subtilis, showed significant biofilm inhibition with percentages reaching up to 92.68 % at MIC concentration and BIC50 ranging from 0.05 ± 0.00 mg/mL to 0.17 ± 0.01 mg/mL. The eradication of preformed biofilms was also measured, showing a notable effect with eradication rates exceeding 78 % at concentrations of 4MIC, and BEC50 values ranging from 0.16 ± 0.02 mg/mL to 1.30 ± 0.37 mg/mL. Overall, these finding indicate that the encapsulated EO combination derived from these two Moroccan medicinal plants presents a promising formulation capable of overcoming the limitations associated with free EOs and contributing to the fight against antimicrobial resistance and biofilm-related challenges.}, }
@article {pmid39733752, year = {2024}, author = {Feng, B and Chen, J and Wang, C and Wang, P and You, G and Lin, J and Gao, H}, title = {Removal of ofloxacin and inhibition of antibiotic resistance gene spread during the aerobic biofilm treatment of rural domestic sewage through the micro-nano aeration technology.}, journal = {Journal of hazardous materials}, volume = {486}, number = {}, pages = {137020}, doi = {10.1016/j.jhazmat.2024.137020}, pmid = {39733752}, issn = {1873-3336}, abstract = {Micro-nano aeration (MNA) has great potential for emerging contaminant removal. However, the mechanism of antibiotic removal and antibiotic resistance gene (ARG) spread, and the impact of the different aeration conditions remain unclear. This study investigated the adsorption and biodegradation of ofloxacin (OFL) and the spread of ARGs in aerobic biofilm systems under MNA and conventional aeration (CVA) conditions. Results showed that the MNA increased OFL removal by 17.27 %-40.54 % and decreased total ARG abundance by 36.37 %-54.98 %, compared with CVA. MNA-induced biofilm rough morphology, high zeta potential, and reduced extracellular polymeric substance (EPS) secretion enhanced OFL adsorption. High dissolved oxygen and temperature, induced by MNA-enriched aerobic bacteria and their carrying OFL-degrading genes, enhanced OFL biodegradation. MNA inhibited the enrichment of ARG host bacteria, which acquired ARGs possibly via horizontal gene transfer (HGT). Functional profiles involved in the HGT process, including reactive oxygen species production, membrane permeability, mobile genetic elements (MGEs), adenosine triphosphate synthesis, and EPS secretion, were down-regulated by MNA, inhibiting ARG spread. Partial least-squares path modeling revealed that MGEs might be the main factor inhibiting ARG spread. This study provides insights into the mechanisms by which MNA enhances antibiotic removal and inhibits ARG spread in aerobic biofilm systems.}, }
@article {pmid39733448, year = {2024}, author = {Zhu, X and Chang, W and Kong, Y and Cai, Y and Huang, Z and Wu, T and Zhang, M and Nie, H and Wang, Y}, title = {Effects of low temperature on the microbial community of MBBR filler biofilm.}, journal = {Water science and technology : a journal of the International Association on Water Pollution Research}, volume = {90}, number = {12}, pages = {3166-3179}, pmid = {39733448}, issn = {0273-1223}, mesh = {*Biofilms ; *Bioreactors/microbiology ; Bacteria/genetics/classification/metabolism ; Cold Temperature ; Waste Disposal, Fluid/methods ; Temperature ; Microbiota ; }, abstract = {Moving bed biofilm reactors can purify urban domestic sewage through microbial biodegradation. High-throughput sequencing was used to study the response mechanism of the biofilm microbial community to temperature. The effluent quality of the reactor declined with the decrease in temperature. Proteobacteria, Bacteroidota, and Nitrospirota were the dominant bacteria, accounting for 59.2, 11.9, and 9.4%, respectively. Gammaproteobacteria (38.3%), Alphaproteobacteria (23.2%), and Bacteroidia (12.4%) were the dominant bacteria at the class level. Low temperature had an obvious directional domestication effect on microbial flora, and the composition of the bacterial community was more similar. Pseudomonas was one of the dominant bacterial groups at 5 °C. Nitrospira (p < 0.001) and Trichococcus (p < 0.05) were significantly negatively correlated with effluent ammonia nitrogen and significantly positively correlated with NO3[-] (p < 0.05) at low temperature. Functional bacteria related to chemoheterotrophy (25.88%) and aerobic_chemoheterotrophy (21.56%) accounted for a relatively high proportion. The bacteria related to nitrate reduction only accounted for 2.62%. Studies have shown that low temperatures can inhibit the growth of nitrogen-cycling bacteria, and few domesticated and selected nitrogen-cycling bacteria play a major role in the removal and transformation of ammonia nitrogen. The degradation of chemical oxygen demand can still be achieved through the adsorption and degradation of dominant functional bacteria.}, }
@article {pmid39732630, year = {2024}, author = {Olana, MD and Asrat, D and Swedberg, G}, title = {Antimicrobial resistance profile, biofilm forming capacity and associated factors of multidrug resistance in Pseudomonas aeruginosa among patients admitted at Tikur Anbessa Specialized Hospital and Yekatit 12 Hospital Medical College in Addis Ababa, Ethiopia.}, journal = {BMC infectious diseases}, volume = {24}, number = {1}, pages = {1472}, pmid = {39732630}, issn = {1471-2334}, mesh = {*Biofilms/drug effects/growth &amp; development ; Ethiopia/epidemiology ; Humans ; *Pseudomonas aeruginosa/drug effects/isolation &amp; purification ; *Drug Resistance, Multiple, Bacterial ; Cross-Sectional Studies ; Male ; *Pseudomonas Infections/microbiology/epidemiology ; *Anti-Bacterial Agents/pharmacology ; Female ; Adult ; Middle Aged ; *Microbial Sensitivity Tests ; Young Adult ; Adolescent ; Cross Infection/microbiology/epidemiology ; Child ; Aged ; Hospitals/statistics &amp; numerical data ; Child, Preschool ; Prevalence ; Infant ; }, abstract = {BACKGROUND: Pseudomonas aeruginosa is one of the leading causes of nosocomial infections and the most common multidrug-resistant pathogen. This study aimed to determine antimicrobial resistance patterns, biofilm-forming capacity, and associated factors of multidrug resistance in P. aeruginosa isolates at two hospitals in Addis Ababa, Ethiopia.<br><br>METHODS: A cross-sectional study was conducted from August 2022 to August 2023 at Tikur Anbessa Specialized Hospital and Yekatit 12 Hospital Medical College. Culture and identification of P. aeruginosa were done using standard microbiological methods. An antimicrobial susceptibility test was done by Kirby-Bauer disk diffusion according to CLSI recommendations. The microtiter plate assay method was used to determine biofilm-forming capacity. SPSS version 25 was used for data analysis. Bivariate and multivariable logistic regression were used to assess factors associated with multidrug resistance in P. aeruginosa. The Spearman correlation coefficient (rs&#x2009;=&#x2009;0.266)) was performed to evaluate the relationship between biofilm formation and drug resistance.<br><br>RESULTS: The overall prevalence of P. aeruginosa was 19.6%. High levels of resistance were observed for ciprofloxacin (51.8%), ceftazidime (50.6%), and cefepime (48.2%). The level of multidrug-resistance was 56.6%. The isolates showed better susceptibility to ceftazidime-avibactam (95.2%) and imipenem (79.5%). Overall, 95.2% of P. aeruginosa were biofilm-producing isolates, and 27.7% and 39.8% of isolates were strong and moderate biofilm producers, respectively. A positive correlation and statistically significant relationship was observed between resistance to multiple drugs and the level of biofilm formation (rs&#x2009;=&#x2009;0.266; p-value&#x2009;=&#x2009;0.015). Previous history of exposure to ciprofloxacin (OR, 5.1; CI, 1.12-24.7, p-value, 0.032) was identified as an independent associated factor for multidrug resistance in P. aeruginosa.<br><br>CONCLUSION: The present study indicates an association between multidrug resistance in P. aeruginosa and its biofilm formation capabilities. Additionally, over half of the isolates were resistant to multiple drugs, with prior use of ciprofloxacin linked to the development of multidrug-resistance. These findings suggest that antibiotic stewardship programs in hospital settings may be beneficial in addressing resistance.}, }
@article {pmid39732619, year = {2025}, author = {Jeong, SY and Lee, JW and Kim, EJ and Lee, CW and Kim, TG}, title = {Comparison of crystal violet staining, microscopy with image analysis, and quantitative PCR to examine biofilm dynamics.}, journal = {FEMS microbiology letters}, volume = {372}, number = {}, pages = {}, doi = {10.1093/femsle/fnae115}, pmid = {39732619}, issn = {1574-6968}, support = {//National Research Foundation of Korea/ ; RS-2023-00273372//Ministry of Education/ ; }, mesh = {*Biofilms/growth &amp; development ; *Gentian Violet ; *Microscopy/methods ; *Staining and Labeling/methods ; *Real-Time Polymerase Chain Reaction/methods ; Bacteria/genetics/growth &amp; development/isolation &amp; purification/classification ; Image Processing, Computer-Assisted/methods ; Biomass ; Bacterial Physiological Phenomena ; }, abstract = {Crystal-violet staining, microscopy with image analysis, and quantitative PCR (qPCR) were compared to examine biofilm dynamics. Biofilms of 30 polycultures comprising 15 bacterial species were monitored for 14 days. Collectively, qPCR (representing population) revealed a different growth pattern compared to staining (biomass) and microscopy (colonization): biomass and colonization gradually increased over time, whereas population increased rapidly for the first seven days and leveled off. Temporal forms were categorized into two growth patterns: continuous increase (CI) and non-continuous increase. Staining and microscopy showed similar odds of detecting the CI pattern (27 and 23 polycultures, respectively) across polycultures, greater than that of qPCR (14 polycultures) (P < 0.05). All three methods revealed the identical patterns for 13 polycultures. Staining with microscopy, staining with qPCR, and microscopy with qPCR found the same patterns in 22, 15, and 19 polycultures, respectively. Additionally, staining was quantitatively agreed with microscopy (P < 0.05; R2 > 0.50), whereas neither staining nor microscopy strongly agreed with qPCR (P < 0.05; R2 ≤ 0.22). Collectively, staining was more compatible with microscopy than qPCR in characterizing biofilm dynamics and quantifying biofilms owing to the difference between population growth and biofilm expansion. The concurrent use of qPCR with biomass estimations allows for accurate and comprehensive biofilm quantification.}, }
@article {pmid39732373, year = {2025}, author = {Yin, S and Wang, YX and Hou, C and Wang, J and Xu, J and Jiang, X and Chen, D and Mu, Y and Shen, J}, title = {Deciphering the key role of biofilm and mechanisms in high-strength nitrogen removal within the anammox coupled partial S[0]-driven autotrophic denitrification system.}, journal = {Bioresource technology}, volume = {419}, number = {}, pages = {132020}, doi = {10.1016/j.biortech.2024.132020}, pmid = {39732373}, issn = {1873-2976}, mesh = {*Biofilms ; *Denitrification/physiology ; *Nitrogen/metabolism ; *Autotrophic Processes ; Oxidation-Reduction ; Sulfur/metabolism ; Bioreactors ; Bacteria/metabolism ; Wastewater/microbiology ; Anaerobiosis/physiology ; Nitrates/metabolism ; }, abstract = {Anammox coupled partial S[0]-driven autotrophic denitrification (PS[0]AD) technology represents an innovative approach for removing nitrogen from wastewater. The research highlighted the crucial role of biofilm on sulfur particles in the nitrogen removal process. Further analysis revealed that sulfur-oxidizing bacteria (SOB) are primarily distributed in the inner layer of the biofilm, while anammox bacteria (AnAOB) are relatively evenly distributed in inner and outer layers, with Thiobacillus and Candidatus Brocadia being the dominant species, respectively. Except for anammox and PS[0]AD processes, [15]N isotope labeling tests determined that sulfur reshaped nitrogen metabolism pathways, providing solid evidence for the occurrence of sulfammox process. SOB and AnAOB collaborate in nitrogen and sulfur conversion, with SOB-drived PS[0]AD processes reducing nitrate to nitrite for AnAOB to remove ammonia. Conversely, the nitrate produced from anammox process can be reused by SOB. Metagenomic analyses verified that SOB drove the PS[0]AD process through encoding soxBYZ gene, while AnAOB might play an important role in simultaneously driving the anammox and sulfammox processes. These findings underscore the importance of biofilm and clarify the nitrogen-sulfur cycle mechanisms within the coupled system.}, }
@article {pmid39732217, year = {2025}, author = {Li, L and Zhang, J and Zhang, Y and Zhao, R and Yang, F and Yan, Y and Wang, Q and Xie, M}, title = {Biofilm-modified Prussian blue improves memory function in late-stage Alzheimer's disease mice with triple therapy.}, journal = {International journal of pharmaceutics}, volume = {670}, number = {}, pages = {125112}, doi = {10.1016/j.ijpharm.2024.125112}, pmid = {39732217}, issn = {1873-3476}, mesh = {Animals ; *Alzheimer Disease/drug therapy ; *Ferrocyanides/chemistry/pharmacology ; Mice ; *Reactive Oxygen Species/metabolism ; *Nanoparticles ; *Amyloid beta-Peptides/metabolism ; Male ; Blood-Brain Barrier/metabolism/drug effects ; Disease Models, Animal ; Memory/drug effects ; Copper/chemistry/administration &amp; dosage ; Photothermal Therapy/methods ; Oxidative Stress/drug effects ; Macrophages/drug effects ; Chelating Agents/chemistry/pharmacology/administration &amp; dosage ; }, abstract = {Alzheimer's disease (AD) is a neurodegenerative disease that is significantly characterized by cognitive and memory impairments, which worsen significantly with age. In the late stages of AD, metal ion disorders and an imbalance of reactive oxygen species (ROS) levels occur in the brain microenvironment, which causes abnormal aggregation of β-amyloid (Aβ), leading to a significant worsening of the AD symptoms. Therefore, we designed a composite nanomaterial of macrophage membranes-encapsulated Prussian blue nanoparticles (PB NPs/MM). Prussian blue nanoparticles (PB NPs) are capable of chelating Cu[2+] and reducing ROS. Macrophage membranes (MM) have advantages over liposomal and erythrocyte membrane carriers, including inflammatory targeting capabilities and more effective immune evasion. Concurrently, the excellent photothermal ability of PB NPs can briefly open the blood-brain barrier (BBB) under near-infrared laser irradiation, which improves the transport efficiency of PB NPs/MM across the BBB and ablates Aβ deposition, thus achieving optimal therapeutic efficacy. In vitro experiments demonstrated that PB NPs/MM is a multifunctional nanosystem, which can effectively inhibit Cu[2+]-induced Aβ monomers aggregation, photothermally depolymerize Aβ fibrils, and attenuate oxidative stress through the combined treatment of chelating metals, photothermal therapy and scavenging ROS. In behavioral experiments, it also significantly improved the cognitive and learning deficits in late-stage APP/PS1 mice, thereby providing new ideas for the treatment of late-stage AD and other neurodegenerative diseases.}, }
@article {pmid39731595, year = {2024}, author = {Yazdanpanah, S and Shafiekhani, M and Emami, M and Khodadadi, H and Pakshir, K and Zomorodian, K}, title = {Exploring the anti-biofilm and gene regulatory effects of anti-inflammatory drugs on Candida albicans.}, journal = {Naunyn-Schmiedeberg's archives of pharmacology}, volume = {}, number = {}, pages = {}, pmid = {39731595}, issn = {1432-1912}, abstract = {Researchers have repurposed several existing anti-inflammatory drugs as potential antifungal agents in recent years. So, this study aimed to investigate the effects of anti-inflammatory drugs on the growth, biofilm formation, and expression of genes related to morphogenesis and pathogenesis in Candida albicans. The minimum inhibitory concentration (MIC) of anti-inflammatory drugs was assessed using the broth microdilution method. Biofilm formation in C. albicans was evaluated using XTT reduction assay following exposure to different concentrations of drugs. Additionally, the expression of adhesin-related genes (ALS1, ALS3), hyphal cell wall specific genes (EAP1, HWP1), secreted aspartyl proteinase (SAP4, SAP6), and morphogenesis pathway regulatory gene (EFG1) was analyzed using quantitative RT-PCR. Betamethasone and dexamethasone markedly inhibited C. albicans biofilm formation by up to 80% at a concentration of 2 mg/mL. Moreover, the inhibition of C. albicans biofilm formation was significant at concentrations ranging from 0.6 to 10 mg/mL for piroxicam and from 0.75 to 12 mg/mL for diclofenac. The expression of key genes involved in biofilm formation including EFG1, HWP1, and ALS3 was all downregulated under hyphae-inducing conditions. Moreover, the expression proteinase genes of C. albicans were upregulated following exposure with corticosteroids. The data obtained provides valuable insights into the antifungal potential of anti-inflammatory drugs. Our novel findings indicate the downregulation of several Candida genes that are crucial for morphogenesis, pathogenesis, and biofilm formation. However, further research is necessary to fully elucidate the clinical applications and effectiveness of anti-inflammatory drugs as alternative or adjunctive therapies for Candida infections.}, }
@article {pmid39729737, year = {2025}, author = {Dey, S and Nayak, AK and Rajaram, H and Das, S}, title = {Exploitative stress within Bacillus subtilis biofilm determines the spatial distribution of pleomorphic cells.}, journal = {Microbiological research}, volume = {292}, number = {}, pages = {128034}, doi = {10.1016/j.micres.2024.128034}, pmid = {39729737}, issn = {1618-0623}, mesh = {*Biofilms/growth &amp; development ; *Bacillus subtilis/physiology ; *Stress, Physiological ; Hydrogen-Ion Concentration ; Phenotype ; }, abstract = {Bacteria commonly live in a spatially organized biofilm assemblage. The metabolic activity inside the biofilm leads to segmented physiological microenvironments. In nature, bacteria possess several pleomorphic forms to withstand certain ecological alterations. We hypothesized that pleomorphism also exists within the biofilm, which can be considered as the fundamental niche for bacteria. We report a distinct pattern of cell size variation throughout the biofilm of Bacillus subtilis. Cell size heterogeneity was observed in biofilm development, wherein the frequency of long cells is higher in outer regions, whereas lower in inner regions. Moreover, compared to planktonic cells, bacteria in the biofilm mode reduce their geometric ratio from 8.34 to 3.69 and 2.65 in the outer and inner regions, respectively. There were no significant differences observed in nutrient diffusion from the outer to the inner region, and more than 73 % of cells in the inner region were viable. However, the inner and middle regions were more acidic than the outer of the biofilm. Conclusively, growth rate-independent cell size reduction at low pH suggests that the resulting phenotype switching within biofilm was observed due to the pH gradient of neutral to acidic from the outer to the core of the biofilm. This gradient of H[+] ions concentration may create exploitative stress within the biofilm, which could favor specific pleomorphic cells to thrive in their specialized niches. By understanding the cell size variation in response to the local environment, we propose a model of biofilm formation by pleomorphic cells.}, }
@article {pmid39727871, year = {2024}, author = {Wu, W and Hong, H and Lin, J and Yang, D}, title = {Antimicrobial Responses to Bacterial Metabolic Activity and Biofilm Formation Studied Using Microbial Fuel Cell-Based Biosensors.}, journal = {Biosensors}, volume = {14}, number = {12}, pages = {}, pmid = {39727871}, issn = {2079-6374}, support = {2021J01313//Natural Science Foundation of Fujian Province/ ; }, mesh = {*Biofilms/drug effects ; *Biosensing Techniques ; *Bioelectric Energy Sources ; *Pseudomonas aeruginosa/drug effects ; *Silver/pharmacology ; *Metal Nanoparticles ; Anti-Bacterial Agents/pharmacology ; }, abstract = {Simultaneous monitoring of antimicrobial responses to bacterial metabolic activity and biofilm formation is critical for efficient screening of new anti-biofilm drugs. A microbial fuel cell-based biosensor using Pseudomonas aeruginosa as an electricigen was constructed. The effects of silver nanoparticles (AgNPs) on the cellular metabolic activity and biofilm formation of P. aeruginosa in the biosensors were investigated and compared with the traditional biofilm detection method. The crystal violet staining results showed that the concentration of AgNPs being increased to 20 and 40 μg/mL had a slight and obvious inhibitory effect on biofilm formation, respectively. In comparison, the detection sensitivity of the biosensor was much higher. When the concentration of AgNPs was 5 μg/mL, the output voltage of the biosensor was suppressed, and the inhibition gradually increased with the AgNPs dose. AgNPs inhibited the activity of planktonic cells in the anolyte and the formation of biofilm on the anode surface, and it had a dose-dependent effect on the secretion of phenazine in the anolyte. The biosensor could monitor the impacts of AgNPs not only on biofilm formation but also on cell activity and metabolic activity. It provides a new and sensitive method for the screening of anti-biofilm drugs.}, }
@article {pmid39727743, year = {2024}, author = {Matsumoto, S and Tatsuoka, H and Yoshii, M and Nagao, T and Shimizu, T and Shingubara, S and Tanaka, S and Ito, T}, title = {Anti-Biofilm Performance of Resin Nanopillars Inspired from Cicada Wing Surface for Staphylococcus spp.}, journal = {Biomimetics (Basel, Switzerland)}, volume = {9}, number = {12}, pages = {}, pmid = {39727743}, issn = {2313-7673}, support = {21H01773//Japan Society for the Promotion of Science/ ; }, abstract = {The increase in infections derived from biofilms from Staphylococcal spp. prompted us to develop novel strategies to inhibit biofilm development. Nanoscale protrusion structures (nanopillars) observed on the wings of dragonflies and cicadas have recently gained notable attention owing to their physical, antimicrobial, and bactericidal properties. Thus, they are not only expected to reduce the damage caused by chemical antimicrobial agents to human health and the environment, but also to serve as a potential countermeasure against the emergence of antimicrobial-resistant bacteria (ARB). In this study, we evaluated the anti-biofilm effects of cyclo-olefin polymer (COP) nanopillars by changing the wettability of surfaces ranging in height from 100 to 500 nm against Staphylococcus spp., such as Staphylococcus aureus NBRC 100910 (MSSA), Staphylococcus aureus JCM 8702 methicillin-resistant S. aureus (MRSA), and Staphylococcus epidermidis ATCC 35984. The results clearly show that the fabricated nanopillar structures exhibited particularly strong biofilm inhibition against MRSA, with inhibition rates ranging from 51.2% to 62.5%. For MSSA, anti-biofilm effects were observed only at nanopillar heights of 100-300 nm, with relatively low hydrophobicity, with inhibition rates ranging from 23.9% to 40.8%. Conversely, no significant anti-biofilm effect was observed for S. epidermidis in any of the nanopillar structures. These findings suggest that the anti-biofilm properties of nanopillars vary among bacteria of the same species. In other words, by adjusting the height of the nanopillars, selective anti-biofilm effects against specific bacterial strains can be achieved.}, }
@article {pmid39726405, year = {2024}, author = {Sakava, P and Nyemb, JN and Matchawe, C and Kumcho, MP and Tagatsing, MF and Nsawir, BJ and Talla, E and Atchadé, AT and Laurent, S and Henoumont, C}, title = {Chemical constituents and antibacterial activities of Cameroonian dark brown propolis against potential biofilm-forming bacteria.}, journal = {Natural product research}, volume = {}, number = {}, pages = {1-14}, doi = {10.1080/14786419.2024.2437024}, pmid = {39726405}, issn = {1478-6427}, abstract = {Propolis is a resinous material collected by different bee species from various plant exudates and used to seal holes in honeycombs, smoothen the internal walls, embalm intruders, improve health and prevent diseases. From its n-hexane extract, eight compounds were isolated and characterised as: mangiferonic acid (1); 1-hydroxymangiferonic acid (2), new natural product; mangiferolic acid(3); 27-hydroxymangiferolic acid (4), reported here for the first time as propolis constituent; 27-hydroxymangiferonic acid (5); α-amyrin (6); β-amyrin (7) and lupeol (8). The chemical structures of the isolated compounds were elucidated using spectroscopic methods, such as 1D and 2D-NMR, mass spectrometry and comparison with previous published reports. Compounds 6-8 and n-hexane extract were tested against Gram-negative and Gram-positive bacteria strains using agar disc diffusion and macrodilution techniques. Interestingly, n-hexane extract and compounds 6-8 had good inhibitory activities against Methicillin Resistant Staphylococcus aureus (MRSA) and the clinical Klebsiella pneumoniae isolates. The biological effects of n-hexane extract and its fraction against K. pneumoniae 12 CM and MRSA revealed in the present study suggest that the Cameroonian dark brown propolis could be a potential alternative management of biofilms on medical devices and respiratory skin or infections.}, }
@article {pmid39725043, year = {2025}, author = {Mumin, YM and Yüksel, G and Özad Düzgün, A}, title = {Investigation of virulence factor genes and biofilm formation of antibiotic resistant clinical E.coli isolates.}, journal = {Microbial pathogenesis}, volume = {199}, number = {}, pages = {107257}, doi = {10.1016/j.micpath.2024.107257}, pmid = {39725043}, issn = {1096-1208}, mesh = {*Biofilms/growth &amp; development/drug effects ; *Virulence Factors/genetics ; *Escherichia coli/genetics/drug effects/isolation &amp; purification ; Humans ; *Anti-Bacterial Agents/pharmacology ; *Escherichia coli Infections/microbiology ; *Microbial Sensitivity Tests ; *Drug Resistance, Bacterial/genetics ; Polymerase Chain Reaction ; Escherichia coli Proteins/genetics ; Genes, Bacterial/genetics ; }, abstract = {PURPOSE: The aim of this study is to investigate the antibiotic sensitivity, presence of virulence genes and biofilm formation capacity of 90 clinical E. coli isolates.<br><br>METHODS: The presence of virulence genes in E.coli isolates were investigated by PCR. Ninety clinical isolates of E.coli were subjected to biofilm quantitative analysis using the semi-quantitative crystal violet staining method.<br><br>RESULTS: it was observed that the isolates were resistant to quinolone, cephalosporin, aminoglycoside, carbapenem and penicillin group antibiotics. The presence of virulence factor genes were observed in a total of 86/90&#xa0;E. coli. The highest rate of fim (92.2&#xa0;%) virulence factor gene was detected in the strains. Afa, pap, cnf, sfa, hly were detected in 30&#xa0;%, 13&#xa0;%, 13&#xa0;%, 3.3&#xa0;%, 2.2&#xa0;% respectively. Also, 13 different virulence factor gene patterns were determined in 90&#xa0;E. coli isolates. Of the 90&#xa0;E. coli isolates whose biofilm-forming capacities were evaluated, 42 were found to have biofilm-forming capacity. Of these 26 (28.8&#xa0;%) the weak, 12 (13.3&#xa0;%) moderate and 4 (4.4&#xa0;%) strong biofilm-forming. Also, statistical analysis was performed to investigate the relationship between virulence factor genes and biofilm formation, and none of the 7 genes analyzed showed a significant relationship with biofilm formation.<br><br>CONCLUSION: since pathogenic E. coli is an important public health problem, investigating antibiotic resistance, virulence factor genes and biofilm formation in bacterial pathogens is important for better treatment options.}, }
@article {pmid39723739, year = {2025}, author = {Wang, JL and Pan, X and Li, X and Liu, KM and Yao, M and An, JY and Wan, Y and Yu, XQ and Feng, S and Wu, MY}, title = {Photoimmunologic Therapy of Stubborn Biofilm via Inhibiting Bacteria Revival and Preventing Reinfection.}, journal = {Advanced materials (Deerfield Beach, Fla.)}, volume = {37}, number = {6}, pages = {e2411468}, doi = {10.1002/adma.202411468}, pmid = {39723739}, issn = {1521-4095}, support = {22177094//National Natural Science Foundation of China/ ; 22174117//National Natural Science Foundation of China/ ; YJ202419//Fundamental Research Funds for the Central Universities/ ; }, mesh = {*Biofilms/drug effects ; *Methicillin-Resistant Staphylococcus aureus/drug effects/physiology ; *Photochemotherapy/methods ; *Photosensitizing Agents/pharmacology/chemistry ; Animals ; Mice ; *Staphylococcal Infections/drug therapy ; Polyethylene Glycols/chemistry ; Anti-Bacterial Agents/pharmacology/chemistry ; Immunotherapy ; Reinfection ; Quorum Sensing/drug effects ; }, abstract = {Stubborn biofilm infections pose serious threats to public health. Clinical practices highly rely on mechanical debridement and antibiotics, which often fail and lead to persistent and recurrent infections. The main culprits are 1) persistent bacteria reviving, colonizing, and rejuvenating biofilms, and 2) secondary pathogen exposure, particularly in individuals with chronic diseases. Addressing how to inhibit persistent bacteria revival and prevent reinfection simultaneously is still a major challenge. Herein, an oligo-ethylene glycol-modified lipophilic cationic photosensitizer (PS), TBTCP-PEG7, is developed. It effectively eradicates Methicillin-Resistant Staphylococcus aureus (MRSA) under light irradiation. Furthermore, TBTCP-PEG7-mediated photodynamic therapy (PDT) not only conquers stubborn biofilm infections by downregulating the two-component system (TCS), quorum sensing (QS), and virulence factors, thereby reducing intercellular communication, inhibiting persistent bacterial regrowth and biofilm remodeling but also prevents reinfection by upregulating heat shock protein-related genes to induce immunogenetic cell death (ICD) and establish immune memory. In vivo, TBTCP-PEG7 efficiently eradicates MRSA biofilm adhered to medical catheters, stimulates angiogenesis, reduces inflammatory factor expression, and accelerates wound healing. Furthermore, ICD promotes short-term immune and long-term immunological memory for coping with secondary infections. This two-pronged strategy not only effectively overcomes stubborn, persistent and recurrent biofilm infection, but also provides theoretical guidance for designing the next generation of antibacterial materials.}, }
@article {pmid39723738, year = {2025}, author = {Yao, K and Cheung, SW and Tang, Y and Dong, J and Feng, S and Xu, J and Xiang, L and Zhou, X}, title = {Photoelectron Therapy Preventing the Formation of Bacterial Biofilm on Titanium Implants.}, journal = {Small (Weinheim an der Bergstrasse, Germany)}, volume = {21}, number = {6}, pages = {e2409824}, doi = {10.1002/smll.202409824}, pmid = {39723738}, issn = {1613-6829}, support = {82370996//National Natural Science Foundation of China/ ; 22108179//National Natural Science Foundation of China/ ; 82170997//National Natural Science Foundation of China/ ; YJ202081//Fundamental Research Funds for the Central Universities in China/ ; 2024NSFSC0537//Sichuan Province Science and Technology Support Program/ ; }, mesh = {*Titanium/chemistry ; *Biofilms/drug effects ; *Prostheses and Implants ; Bacterial Adhesion/drug effects ; Nanotubes/chemistry ; Surface Properties ; }, abstract = {The exogenous bacterial infection and formation of biofilm on the surface of titanium implants can affect the adhesion, proliferation, and differentiation of cells associated with osteogenesis, ultimately leading to surgical failure. This study focuses on two critical stages for biofilm formation: i) bacterial adhesion and aggregation, ii) growth and proliferation. The titanium with well-organized titania nanotube arrays is first modified by nitrogen dopants, then loaded with CuFeSe2 nanoparticles to form a p-n heterojunction. Such heterojunction can effectively separate the electrons and holes generated by CuFeSe2 under NIR excitation, where CuFeSe2 serves as an electron acceptor from adherent bacteria, thus disrupting the respiratory chain and eventually affecting the metabolism. Combined with the released ions in solution and photothermal effect, the formation of bacterial biofilm on the surface of titanium implants is prevented on both stages.}, }
@article {pmid39723056, year = {2024}, author = {Quradha, MM and Tamfu, AN and Duru, ME and Kucukaydin, S and Iqbal, M and Qahtan, AMF and Khan, R and Ceylan, O}, title = {Evaluation of HPLC Profile, Antioxidant, Quorum Sensing, Biofilm, Swarming Motility, and Enzyme Inhibition Activities of Conventional and Green Extracts of Salvia triloba.}, journal = {Food science &amp; nutrition}, volume = {12}, number = {12}, pages = {10716-10733}, pmid = {39723056}, issn = {2048-7177}, abstract = {The current study aims to prepare a green extract using a new method in addition to conventional extraction methods including; methanolic and ultrasonic extraction of Salvia triloba, to compare their phenolic composition utilizing high-performance liquid chromatograph equipped with a diode array detector (HPLC-DAD), anti-bacterial, anti-oxidant, and enzyme inhibition activities. The results of HPLC-DAD analysis showed that Rosmarinic acid was found the highest amount in the methanolic extract followed by ultrasonic and green extracts as 169.7 ± 0.51, 135.1 ± 0.40, and 28.58 ± 0.46 μg/g respectively. The Trans-cinnamic acid (4.40 ± 0.09 μg/g) was found exclusively in ultrasonic extract. For bioactivities, the green extract exhibited the highest biofilm inhibition against Enterococcus faecalis compared to other extracts, while the methanolic extract outperformed both ultrasonic-assisted and green extract against Staphylococcus aureus and Escherichia coli strains at minimum inhibitory concentration. The methanolic and green extract exhibited considerable quorum sensing inhibition against Chromobacterium violaceum CV026, while no activity was recorded from ultrasonic-assisted extract. The methanolic and ultrasonic-assisted extracts of S. triloba recorded moderate butyrylcholinesterase inhibition; each extract demonstrated limited inhibitory effects on the urease enzyme. Similarly, each extract of S. triloba demonstrated significant antioxidant activity, with the highest activity exhibited by methanolic extract as β-carotene-linoleic acid assay (IC50 = 10.29 ± 0.36 μg/mL), DPPH[•] assay (IC50 = 27.77 ± 0.55 μg/mL), ABTS[•+] assay (IC50 = 15.49 ± 0.95 μg/mL), metal chelating assay (IC50 = 57.80 ± 0.95 μg/mL), and CUPRAC (assay A 0.50 = 32.54 ± 0.84 μg/mL). Furthermore, the methanolic extract exhibited antioxidant activity better than α-tocopherol (Standard used). The current study demonstrated the potential of green solvent(s) as eco-friendly alternative for extractin phenolic compounds from S. triloba and evaluated their biological activities for the first time.}, }
@article {pmid39723028, year = {2024}, author = {López-García, E and Benítez-Cabello, A and Arroyo-López, FN}, title = {Effects of Phenolic Compounds on Biofilm Formation by Table Olive-Related Microorganisms.}, journal = {Food science &amp; nutrition}, volume = {12}, number = {12}, pages = {10924-10932}, pmid = {39723028}, issn = {2048-7177}, abstract = {The process of biofilm formation during table olive fermentation is crucial to turning this fermented vegetable into a probiotic food. Some phenolic compounds have been described as important quorum-sensing molecules during biofilm development. The present in vitro study examined the effects of three phenolic compounds widely found in table olive fermentations (Oleuropein 0-3000 ppm, Hydroxytyrosol 0-3000 ppm, and Tyrosol 0-300 ppm) on the development of single biofilm by diverse microorganisms isolated from table olives (Lactiplantibacillus pentosus 13B4, Lp119, and LPG1; Lactiplantibacillus plantarum Lp15 and LAB23; and yeasts Wickerhamomyces anomalus Y12, Candida boidinii Y13, and Saccharomyces cerevisiae Y18). Biofilm formation was quantified in vitro by crystal violet staining in microtiter plates after incubation at 30°C for 96 h. A clear tendency to decrease the biofilm production was observed for the L. plantarum strains when any of the three phenolic compounds were added to the medium, which was statistically significant (p ≤ 0.05) for certain concentrations and phenols. In the case of yeasts, no statistical influence on biofilm formation was noticed when the phenolic compounds were dosed to the culture medium. Finally, the effects of the phenolic compounds on the L. pentosus strains were dependent on the strain assayed. Thereby, addition of phenolic compounds on 13B4 or Lp119 strains did not have statistical influence on biofilm production. On the contrary, the probiotic LPG1 strain noticed a statistical increase in biofilm production when a low concentration of tyrosol (50 ppm) was added to the medium. Results obtained in this work could be useful to control the biofilm formation process on olive epidermis during table olive fermentation to include beneficial microorganisms.}, }
@article {pmid39722993, year = {2024}, author = {Jaisal, S and Singh, A and Verma, RK and Ram, VS and Verma, SK and Yadav, H and Prakash, V}, title = {Evaluation of biofilm formation and carbapenem resistance in Klebsiella pneumoniae isolated from clinical samples at a rural hospital in western Uttar Pradesh.}, journal = {Journal of family medicine and primary care}, volume = {13}, number = {11}, pages = {4894-4900}, pmid = {39722993}, issn = {2249-4863}, abstract = {INTRODUCTION: Klebsiella pneumoniae commonly causes healthcare-associated infections and shows multidrug resistance. K. pneumoniae can produce biofilm. Carbapenem resistance in K. pneumoniae is due to the production of carbapenemases mainly. This study was done to evaluate the formation of biofilm and carbapenemase resistance in K. pneumoniae isolates.<br><br>MATERIAL AND METHODS: A total of 110 K. pneumoniae isolated from various clinical samples were taken, the antibiotic susceptibility test was done by the Kirby disk diffusion method, and biofilm detection was done by the tissue culture plate method. All the carbapenem-resistant isolates were confirmed by multiplex real-time PCR (mPCR). Those found positive for any of the carbapenemase genes were tested by the modified Hodge test (MHT), modified carbapenem inactivation method (mCIM), and ethylenediamine tetraacetic acid (EDTA)-modified carbapenem inactivation method (eCIM).<br><br>RESULTS: Out of 110 isolates, 66% (72/110) were carbapenem-resistant (suggestive of carbapenemase producers) by Kirby-Bauer disk diffusion but 58% (42/72) of Klebsiella isolates were confirmed for carbapenemase production by mPCR. Maximum number of carbapenemase gene were New Delhi metallo-&#x3b2;-lactamase (NDM) 52% (N = 22), 29% (N = 12) coproducers (NDM+OXA-48), and lowest in oxacillinase (OXA-48), 19% (N = 8). The overall sensitivity of MHT and mCIM+eCIM was 62% and 93%, and specificity was 88% and 97%, respectively. Our study showed that moderate biofilm producers were 51% (N = 56) K. pneumoniae isolates, strong biofilm producers 27% (N = 30), and 22% (N = 30) were weak/non-biofilm producers. We also found the correlation between biofilm formation and carbapenem-resistant K. pneumoniae (CR-KP) genes was statistically significant with a P value of 0.01*<0.05.<br><br>CONCLUSION: Most isolates of K. pneumoniae demonstrated a wide range of antibiotic resistance and were biofilm producers. Our results indicated that the combination of mCIM with eCIM showed high sensitivity and specificity to detect CR-KP compared with MHT.}, }
@article {pmid39722480, year = {2024}, author = {Lekkala, VVV and Sirigireddy, B and Reddy, MC and Lomada, D}, title = {Synthesis and Characterization of Silver and Zinc Nanoparticles From Vitex altissima: Comparative Analysis of Anti-Oxidant, Anti-Inflammatory, Antibacterial, and Anti-Biofilm Activities.}, journal = {Chemistry &amp; biodiversity}, volume = {}, number = {}, pages = {e202402166}, doi = {10.1002/cbdv.202402166}, pmid = {39722480}, issn = {1612-1880}, abstract = {Metal nanoparticles have attained much popularity due to their low toxicity, economic feasibility, and eco-friendly nature. The present study focuses on the synthesis of silver and zinc nanoparticles from Vitex altissima leaf extract, further characterized by UV/Vis spectral analysis, Powder-x-ray diffraction (XRD), FE-SEM, Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), dynamic light scattering (DLS), and zeta potential. Synthesized silver and zinc nanoparticles were screened for antioxidant, anti-inflammatory, antibacterial, and anti-biofilm activities. AgNPs exhibited moderate antioxidant activities compared to ZnNPs, which were studied using 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and ABTS assays. The anti-inflammatory effect was assessed using membrane stabilization and human red blood cell methods. Furthermore, both types of nanoparticles, AgNPs and ZnNPs, exhibited anti-biofilm activity against four MDR bacterial strains: Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Synthesized nanoparticles show antibacterial activity. Our data suggest that silver nanoparticles exhibited moderate activity compared to ZnNPs. These nanoparticles could act as potential antioxidant, anti-inflammatory, and antibacterial agents.}, }
@article {pmid39722442, year = {2024}, author = {Huang, Y and Yu, S and Liu, S and Zhao, X and Chen, X and Wei, X}, title = {Autophagy Activated by Atg1 Interacts With Atg9 Promotes Biofilm Formation and Resistance of Candida albicans.}, journal = {Journal of basic microbiology}, volume = {}, number = {}, pages = {e2400603}, doi = {10.1002/jobm.202400603}, pmid = {39722442}, issn = {1521-4028}, support = {//This work was supported by the National Natural Science Foundation of China (grant number 81970945). The recipient of this fund is Xin Wei./ ; }, abstract = {Autophagy regulates the development of Candida albicans (C. albicans) biofilms and their sensitivity to antifungals. Atg1, a serine/threonine protein kinase, recruits autophagy-related proteins for autophagosome formation. Atg9, the only transmembrane protein, is phosphorylated by Atg1 during autophagy. The specific roles of Atg1 and Atg9 in biofilm formation and resistance of C. albicans remain unclear. The study used RT-qPCR and Western blotting to assess the correlation between Atg1, Atg9 and biofilm formation, XTT reduction assays to evaluate biofilm formation and antifungal resistance, commercial kits to detect reactive oxygen species (ROS), mitochondrial membrane potential (MMP), and autophagy activity, transmission electron microscopy (TEM) to study the morphological changes, protein-protein interaction (PPI) analysis to analyze the interaction between Atg1 and Atg9. Results demonstrated that Atg1 and Atg9 were highly expressed in biofilms than planktonic cells. Biofilm formation, antifungal resistance, MMP and autophagy activity decreased and ROS increased in atg1Δ/Δ and atg9Δ/Δ. TORC1 inhibition with rapamycin rescued the reduced biofilm formation of atg1Δ/Δ and increased antifungal resistance of atg1Δ/Δ and atg9Δ/Δ. PPI analysis and TEM observation indicated that Atg1 interacted with Atg9, which was certified by RT-qPCR and Western blotting. This study suggested that Atg1 interacts with Atg9, activates the autophagy regulating the formation and sensitivity of C. albicans biofilms.}, }
@article {pmid39721302, year = {2025}, author = {Taha, AB}, title = {Bacteriological profile, antibiotic susceptibility, and biofilm formation in children with chronic suppurative otitis media.}, journal = {International journal of pediatric otorhinolaryngology}, volume = {188}, number = {}, pages = {112208}, doi = {10.1016/j.ijporl.2024.112208}, pmid = {39721302}, issn = {1872-8464}, mesh = {Humans ; *Otitis Media, Suppurative/microbiology/drug therapy ; *Biofilms/drug effects ; Cross-Sectional Studies ; Child ; Male ; Female ; *Microbial Sensitivity Tests ; Child, Preschool ; Chronic Disease ; *Anti-Bacterial Agents/pharmacology/therapeutic use ; Drug Resistance, Bacterial ; Infant ; Pseudomonas aeruginosa/isolation &amp; purification/drug effects ; Staphylococcus aureus/isolation &amp; purification/drug effects ; Adolescent ; }, abstract = {BACKGROUND: Chronic suppurative otitis media is predominantly caused by aerobic bacterial infections, complicated by antibiotic-resistant strains and biofilm formation. This study aims to identify the aerobic bacterial pathogens in chronic suppurative otitis media among children and assess their antibiotic susceptibility patterns. The potential link between biofilm formation and antibiotic resistance is also evaluated.<br><br>METHODS: A cross-sectional study was conducted on 457 children with chronic suppurative otitis media. Middle ear discharge samples were collected and aerobic bacteria were isolated and identified using standard microbiological methods. Antibiotic susceptibility was determined by the agar dilution method, and biofilm formation was assessed using the microtiter plate assay.<br><br>RESULTS: Of the 457 cases, 89.72&#xa0;% were monomicrobial infections. The most prevalent Gram-negative bacterium was Pseudomonas aeruginosa (35.71&#xa0;%), while Staphylococcus aureus (26.27&#xa0;%) was the leading Gram-positive pathogen. Pseudomonas aeruginosa demonstrated high resistance, with 96.77&#xa0;% resistant to cefuroxime and 92.26&#xa0;% to amoxicillin/clavulanic acid. Similarly, Staphylococcus aureus showed significant resistance to ampicillin (83.33&#xa0;%) and amoxicillin (78.07&#xa0;%). A strong correlation (p&#xa0;<&#xa0;0.001) was observed between biofilm formation and antibiotic resistance, with Gram-negative bacteria resisting an average of 4.24&#xa0;&#xb1;&#xa0;1.769 antibiotics and Gram-positive bacteria resisting 5.13&#xa0;&#xb1;&#xa0;1.535 antibiotics.<br><br>CONCLUSION: A high prevalence of antibiotic-resistant pathogens has been observed in children with chronic suppurative otitis media, with a significant association between biofilm formation and antibiotic resistance.}, }
@article {pmid39720794, year = {2024}, author = {González, JF and Laipply, B and Sadowski, VA and Price, M and Gunn, JS}, title = {Functional role of the biofilm regulator CsgD in Salmonella enterica sv. Typhi.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1478488}, pmid = {39720794}, issn = {2235-2988}, mesh = {*Biofilms/growth &amp; development ; *Bacterial Proteins/genetics/metabolism ; *Gene Expression Regulation, Bacterial ; Salmonella typhi/genetics/metabolism/physiology ; Humans ; Typhoid Fever/microbiology ; Fimbriae, Bacterial/metabolism/genetics ; }, abstract = {INTRODUCTION: Typhoid fever is an infectious disease primarily caused by Salmonella enterica sv. Typhi (S. Typhi), a bacterium that causes as many as 20 million infections and 600,000 deaths annually. Asymptomatic chronic carriers of S. Typhi play a major role in the transmission of typhoid fever, as they intermittently shed the bacteria and can unknowingly infect humans in close proximity. An estimated 90% of chronic carriers have gallstones; biofilm formation on gallstones is a primary factor in the establishment and maintenance of gallbladder carriage. CsgD is a central biofilm regulator in Salmonella, but the S. Typhi csgD gene has a mutation that introduces an early stop codon, resulting in a protein truncated by 8 amino acids at the C-terminus. In this study, we investigate the role of role of CsgD in S. Typhi.<br><br>METHODS: We introduced a fully functional copy of the csgD gene from S. Typhimurium into S. Typhi under both a native and a constitutive promoter and tested for red, dry, and rough (Rdar) colony morphology, curli fimbriae, cellulose, and biofilm formation.<br><br>RESULTS AND DISCUSSION: We demonstrate that although CsgD-regulated curli and cellulose production were partially restored, the introduction of the S. Typhimurium csgD did not induce the Rdar colony morphology. Interestingly, we show that CsgD does not have a significant role in S. Typhi biofilm formation, as biofilm-forming capacities depend more on the isolate than the CsgD regulator. This data suggests the presence of an alternative biofilm regulatory process in this human-restricted pathogen.}, }
@article {pmid39720018, year = {2024}, author = {Doi, H and Mishima, A and Ikeda, R}, title = {Spencermartinsiella japonica f.a., sp. nov., a novel yeast species isolated from biofilm in a reverse osmosis system.}, journal = {Mycoscience}, volume = {65}, number = {5}, pages = {224-227}, pmid = {39720018}, issn = {1618-2545}, abstract = {Novel Spencermartinsiella strains, JCM 35526[T] and 261-2C, were isolated from biofilm formed on a reverse osmosis membrane in the phosphate recovery system of a semiconductor factory. Morphological, biochemical, physiological, and chemotaxonomic analyses as well as sequence analysis of the concatenated internal transcribed spacer region and D1/D2 domains of the large subunit of the rRNA gene confirmed that strains JCM 35526[T] and 261-2C, were distinct from all currently known Spencermartinsiella species. The holotype and isotype strains of the new species, which is named Spencermartinsiella japonica, are JCM 35526[T] and MUCL 58310[I], respectively.}, }
@article {pmid39719371, year = {2025}, author = {Meza-Torres, J and Tinevez, JY and Crouzols, A and Mary, H and Kim, M and Hunault, L and Chamorro-Rodriguez, S and Lejal, E and Altamirano-Silva, P and Groussard, D and Gobaa, S and Peltier, J and Chassaing, B and Dupuy, B}, title = {Clostridioides difficile binary toxin CDT induces biofilm-like persisting microcolonies.}, journal = {Gut microbes}, volume = {17}, number = {1}, pages = {2444411}, doi = {10.1080/19490976.2024.2444411}, pmid = {39719371}, issn = {1949-0984}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Clostridioides difficile/genetics/drug effects/growth &amp; development/physiology/metabolism ; Animals ; Mice ; *Clostridium Infections/microbiology ; *Bacterial Proteins/metabolism/genetics ; Bacterial Toxins/metabolism/genetics ; Humans ; Anti-Bacterial Agents/pharmacology ; Vancomycin/pharmacology ; Colon/microbiology ; Mice, Inbred C57BL ; Cecum/microbiology ; Female ; Disease Models, Animal ; ADP Ribose Transferases ; }, abstract = {Clinical symptoms of Clostridioides difficile infection (CDI) range from diarrhea to pseudomembranous colitis. A major challenge in managing CDI is the high rate of relapse. Several studies correlate the production of CDT binary toxin by clinical strains of C. difficile with higher relapse rates. Although the mechanism of action of CDT on host cells is known, its exact contribution to CDI is still unclear. To understand the physiological role of CDT during CDI, we established two hypoxic relevant intestinal models, Transwell and Microfluidic Intestine-on-Chip systems. Both were challenged with the epidemic strain UK1 CDT[+] and its isogenic CDT[-] mutant. We report that CDT induces mucin-associated microcolonies that increase C. difficile colonization and display biofilm-like properties by enhancing C. difficile resistance to vancomycin. Importantly, biofilm-like microcolonies were also observed in the cecum and colon of infected mice. Hence, our study shows that CDT induces biofilm-like microcolonies, increasing C. difficile persistence and risk of relapse.}, }
@article {pmid39718087, year = {2024}, author = {Piletić, K and Mežnarić, S and Keržić, E and Oder, M and Gobin, I}, title = {Comparison of different disinfection protocols against contamination of ceramic surfaces with Klebsiella pneumoniae biofilm.}, journal = {Arhiv za higijenu rada i toksikologiju}, volume = {75}, number = {4}, pages = {289-296}, pmid = {39718087}, issn = {1848-6312}, mesh = {*Klebsiella pneumoniae/drug effects ; *Biofilms/drug effects ; *Disinfection/methods ; *Ceramics ; *Disinfectants/pharmacology ; Ozone/pharmacology ; Citric Acid/pharmacology ; Benzalkonium Compounds/pharmacology ; Equipment Contamination/prevention &amp; control ; Humans ; }, abstract = {Environmental contamination with Klebsiella pneumoniae biofilm can be a source of healthcare-associated infections. Disinfection with various biocidal active substances is usually the method of choice to remove contamination with biofilm. In this study we tested 13 different disinfection protocols using gaseous ozone, citric acid, and three working concentrations of benzalkonium chloride-based professional disinfecting products on 24-hour-old biofilms formed by two K. pneumoniae strains on ceramic tiles. All tested protocols significantly reduced total bacterial counts compared to control, varying from a log10 CFU reduction factor of 1.4 to 5.6. Disinfection combining two or more biocidal active substances resulted in significantly better anti-biofilm efficacy than disinfection with single substances, and the most effective combination for both strains was that of citric acid, gaseous ozone, and benzalkonium chloride. This follow up study is limited to K. pneumoniae alone, and to overcome this limitation, future studies should include more bacterial species, both Gram-positive and Gramnegative, and more samples for us to find optimal disinfection protocols, applicable in real hospital settings.}, }
@article {pmid39716908, year = {2024}, author = {Wu, X and Pan, B and Chu, C and Zhang, Y and Ma, J and Xing, Y and Ma, Y and Zhu, W and Zhong, H and Alimu, A and Zhou, G and Liu, S and Chen, W and Li, X and Sheng, P}, title = {CXCL16/CXCR6/TGF-β Feedback Loop Between M-MDSCs and Treg Inhibits Anti-Bacterial Immunity During Biofilm Infection.}, journal = {Advanced science (Weinheim, Baden-Wurttemberg, Germany)}, volume = {}, number = {}, pages = {e2409537}, doi = {10.1002/advs.202409537}, pmid = {39716908}, issn = {2198-3844}, support = {82372424//National Natural Science Foundation of China/ ; 82203677//National Natural Science Foundation of China/ ; GZC20233275//Postdoctoral Fellowship Program of CPSF/ ; 82302716//Young Scientists Fund of the National Natural Science Foundation of China/ ; 2024M753776//China Postdoctoral Science Foundation/ ; 2023M744048//China Postdoctoral Science Foundation/ ; 2023A1515140147//Basic and Applied Basic Research Foundation of Guangdong Province/ ; }, abstract = {Staphylococcus aureus (S. aureus) is a leading cause of Periprosthetic joint infection (PJI), a severe complication after joint arthroplasty. Immunosuppression is a major factor contributing to the infection chronicity of S. aureus PJI, posing significant treatment challenges. This study investigates the relationship between the immunosuppressive biofilm milieu and S. aureus PJI outcomes in both discovery and validation cohorts. This scRNA-seq analysis of synovium from PJI patients reveals an expansion and heightened activity of monocyte-related myeloid-derived suppressor cells (M-MDSCs) and regulatory T cells (Treg). Importantly, CXCL16 is significantly upregulated in M-MDSCs, with its corresponding CXCR6 receptor also elevated on Treg. M-MDSCs recruit Treg and enhance its activity via CXCL16-CXCR6 interactions, while Treg secretes TGF-β, inducing M-MDSCs proliferation and immunosuppressive activity. Interfering with this cross-talk in vivo using Treg-specific CXCR6 knockout PJI mouse model reduces M-MDSCs/Treg-mediated immunosuppression and alleviates bacterial burden. Immunohistochemistry and recurrence analysis show that PJI patients with CXCR6[high] synovium have poor prognosis. This findings highlight the critical role of CXCR6 in Treg in orchestrating an immunosuppressive microenvironment and biofilm persistence during PJI, offering potential targets for therapeutic intervention.}, }
@article {pmid39716676, year = {2025}, author = {Tang, T and Zhao, Z}, title = {Deciphering the internal mechanism of nitrogen removal from sludge and biofilm under low temperature from the perspective of microbial function metabolism.}, journal = {Environmental research}, volume = {267}, number = {}, pages = {120688}, doi = {10.1016/j.envres.2024.120688}, pmid = {39716676}, issn = {1096-0953}, mesh = {*Biofilms ; *Sewage/microbiology ; *Nitrogen/metabolism ; *Denitrification ; Cold Temperature ; Waste Disposal, Fluid/methods ; Bacteria/metabolism/genetics ; Nitrification ; }, abstract = {Nitrogen emissions up to the standard are a major challenge for wastewater treatment plants in alpine and high-altitude areas. The dosing of carriers can improve the nitrogen removal efficiency of the system at low temperatures; however, the mechanism of action of sludge and biofilm in nitrogen removal remains unclear. This study elucidated the internal mechanism of nitrogen removal via the function of microbial metabolism in sludge and biofilm at low temperatures. At low temperatures, the biofilm facilitated the enrichment of nitrifying bacteria (5.21%-6.62%) and nitrifying functional genes (amoABC); the average removal efficiency of NH4[+]-N peaked at 94.14%. The denitrification performance of biofilm (14.34-20.67 mg N/(gMLVSS·h) was weaker than that of sludge (27-30.95 mg N/(gMLVSS·h) at low temperatures. The relative abundance of chemical oxygen demand-degrading, denitrifying bacteria, and denitrification functional genes (napAB, nirS, norB, and nosZ) in the sludge was higher than in the biofilm. With a decrease in temperature, the upregulation of carbon metabolism and quorum-sensing functional genes improved the adaptability of sludge to low temperatures. The enhancement of c-type cytochromes and cyclic dimeric guanosine monophosphate functional genes promoted nitrogen removal by endorsing extracellular electron transfer between microorganisms and releasing extracellular polymeric substances at low temperatures. This study offers new insights into improving the mechanism of nitrogen removal from sludge and biofilm at low temperatures.}, }
@article {pmid39716652, year = {2025}, author = {Ghadimi, N and Asadpour, L and Mokhtary, M}, title = {Enhanced antimicrobial, anti-biofilm, and efflux pump inhibitory effects of ursolic acid-conjugated magnetic nanoparticles against clinical isolates of multidrug-resistant Pseudomonas aeruginosa.}, journal = {Microbial pathogenesis}, volume = {199}, number = {}, pages = {107241}, doi = {10.1016/j.micpath.2024.107241}, pmid = {39716652}, issn = {1096-1208}, mesh = {*Pseudomonas aeruginosa/drug effects/genetics ; *Biofilms/drug effects ; *Ursolic Acid ; *Microbial Sensitivity Tests ; *Triterpenes/pharmacology/chemistry ; *Anti-Bacterial Agents/pharmacology ; *Drug Resistance, Multiple, Bacterial/drug effects ; Magnetite Nanoparticles/chemistry ; Humans ; Membrane Transport Proteins/metabolism/genetics ; Pseudomonas Infections/microbiology ; Bacterial Outer Membrane Proteins/metabolism/genetics ; Spectroscopy, Fourier Transform Infrared ; }, abstract = {OBJECTIVES: In the present study, we investigate the effect of Fe3O4 nanoparticles conjugated with ursolic acid (Fe3O4NPs@UA) on inhibiting the growth, biofilm-forming ability and efflux pump activity in clinical isolates of Pseudomonas aeruginosa with multiple drug resistance.<br><br>METHODS: Iron oxide NPs conjugated with ursolic acid (Fe3O4NPs@UA) were synthesized. Physicochemical features of the NPs were studied by FT-IR, XRD, EDAX, and TEM. The antibacterial and antibiofilm effects of Fe3O4NPs@UA against P. aeruginosa isolates were determined by broth microdilution and microtiter plate methods, respectively. The efflux pump inhibitory effect of Fe3O4NPs@UA was determined using Cartwheel method and through determining the expression level of efflux pump genes, including mexA and oprD in selected P. aeruginosa isolates treated with sub-MIC concentration of Fe3O4NPs@UA by real-time PCR.<br><br>RESULTS: In investigating the antimicrobial effect of Fe3O4NPs@UA, the MIC of these nanoparticles varied between 0.19 and 0.78&#xa0;mg/mL and in the study of the anti-biofilm effect of Fe3O4NPs@UA, it caused a 68-75&#xa0;% decrease in biofilm formation compared to the control. Moreover, in the Cartwheel test, the anti-efflux effect of these nanoparticles was confirmed at 1/4-MIC concentrations, and the expression of mexA and oprD genes was reduced in bacteria treated with Fe3O4NPs@UA compared to the control.<br><br>CONCLUSION: According to the results, the use of Fe3O4NPs@UA can provide a basis for the development of new treatments against drug-resistant bacteria in P. aeruginosa. This substance can improve the concentration of antibiotics in bacterial cells and increase their effectiveness by inhibiting the efflux in P. aeruginosa isolates.}, }
@article {pmid39716060, year = {2024}, author = {Fatih, HJ and Ashengroph, M and Sharifi, A and Zorab, MM}, title = {Green-synthesized α-Fe2O3-nanoparticles as potent antibacterial, anti-biofilm and anti-virulence agent against pathogenic bacteria.}, journal = {BMC microbiology}, volume = {24}, number = {1}, pages = {535}, pmid = {39716060}, issn = {1471-2180}, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Microbial Sensitivity Tests ; *Ferric Compounds/chemistry/pharmacology ; *Green Chemistry Technology ; Gram-Positive Bacteria/drug effects ; Gram-Negative Bacteria/drug effects ; Nanoparticles/chemistry ; Bacillus/drug effects ; Virulence/drug effects ; X-Ray Diffraction ; Spectroscopy, Fourier Transform Infrared ; Bacteria/drug effects ; }, abstract = {BACKGROUND: Antimicrobial resistance (AMR) presents a serious threat to health, highlighting the urgent need for more effective antimicrobial agents with innovative mechanisms of action. Nanotechnology offers promising solutions by enabling the creation of nanoparticles (NPs) with antibacterial properties. This study aimed to explore the antibacterial, anti-biofilm, and anti-virulence effects of eco-friendly synthesized α-Fe2O3 nanoparticles (α-Fe2O3-NPs) against pathogenic bacteria.<br><br>METHODS: The &#x3b1;-Fe2O3-NPs were synthesized using a green synthesis method that involved Bacillus sp. GMS10, with iron sulfate as a precursor. The NPs were characterized through ultraviolet-visible (UV-Vis) spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray Spectroscopy (EDX), Dynamic Light Scattering (DLS), Zeta Potential Analysis, X-ray Diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FT-IR). Their antimicrobial activity was assessed against Gram-positive and Gram-negative bacteria. The study also evaluated the effect of the &#x3b1;-Fe2O3-NPs on bacterial cell membrane disruption, biofilm formation, efflux pump inhibition, and swarming motility.<br><br>RESULTS: The UV-Visible spectrum showed a peak at 228&#xa0;nm, indicating plasmon absorbance of the &#x3b1;-Fe2O3-NPs. FESEM revealed spherical NPs (~&#x2009;30&#xa0;nm), and DLS confirmed a hydrodynamic size of 36.3&#xa0;nm with a zeta potential of -25.1 mV, indicating good stability. XRD identified the rhombohedral &#x3b1;-Fe2O3 phase, and FTIR detected O-H, C-H, C&#x2009;=&#x2009;O, and Fe-O functional groups, suggesting organic capping for stability. Antibacterial assays demonstrated that the &#x3b1;-Fe2O3-NPs had MIC values ranging from 0.625 to 5&#xa0;&#xb5;g/mL and MBC values between 5 and 20&#xa0;&#xb5;g/mL, with a strong effect against Gram-positive bacteria. The NPs significantly increased membrane permeability, inhibited biofilm formation in&#xa0;S. aureus and E. coli, and disrupted efflux pumps in&#xa0;S. aureus SA-1199B&#xa0;(a fluoroquinolone-resistant strain overexpressing norA). Additionally, the &#x3b1;-Fe2O3-NPs inhibited P. aeruginosa swarming motility.<br><br>CONCLUSION: The bacteria-synthesized &#x3b1;-Fe2O3-NPs demonstrated significant antimicrobial activity, particularly against Gram-positive bacteria, and exhibited strong potential for inhibiting biofilm formation and efflux pump activity, offering a promising strategy to address AMR. Focus on further evaluating their therapeutic potential in clinical settings and conducting comprehensive assessments of their safety profiles to ensure their applicability in medical treatments.<br><br>CLINICAL TRIAL NUMBER: Not applicable.}, }
@article {pmid39715970, year = {2024}, author = {Thitisakyothin, P and Chanrat, S and Srisatjaluk, RL and Mitrakul, K}, title = {Quantitative analysis of Streptococcus mutans, Bifidobacterium, and Scardovia Wiggsiae in occlusal biofilm and their association with Visible Occlusal Plaque Index (VOPI) and International Caries Detection and Assessment System (ICDAS).}, journal = {European archives of paediatric dentistry : official journal of the European Academy of Paediatric Dentistry}, volume = {}, number = {}, pages = {}, pmid = {39715970}, issn = {1996-9805}, abstract = {AIMS: To quantitatively detect S. mutans, Bifidobacterium, and S. wiggsiae in occlusal biofilm from permanent first molars based on the Visible Occlusal Plaque Index (VOPI), and to analyse the association between their levels and the occlusal enamel caries occurrence following the diagnosis of the International Caries Detection and Assessment System (ICDAS).<br><br>STUDY DESIGN: One hundred twenty plaque samples were collected from children aged 6-8&#xa0;years and divided into four groups (n&#x2009;=&#x2009;30 each group) according to VOPI scores (0&#x2009;=&#x2009;no visible plaque, 1&#x2009;=&#x2009;thin plaque, 2&#x2009;=&#x2009;thick plaque, and 3&#x2009;=&#x2009;heavy plaque). Scores 0 and 1 were identified by running dental probe on the groove. Scores 2 and 3 were visually identified. ICDAS scores were recorded by scoring 0-3 (0&#x2009;=&#x2009;sound tooth surface, 1&#x2009;=&#x2009;opacity or discoloration of enamel after air drying, 2&#x2009;=&#x2009;visual change in enamel when wet, and 3&#x2009;=&#x2009;localised enamel breakdown).<br><br>METHODS: DNA was extracted from plaque samples and performed quantitative real-time PCR using SYBR green and specific primers for total bacteria including the 16S rRNA gene sequences conserved in all bacteria (BAC16S), S. mutans, Bifidobacterium, and S. wiggsiae.<br><br>RESULTS: Ages of the children were different amongst VOPI groups (p&#x2009;<&#x2009;0.001). Levels of total bacteria (p&#x2009;<&#x2009;0.001) and S. mutans (p&#x2009;=&#x2009;0.026) increased when VOPI increased. The ratio of S. mutans to total bacteria (p&#x2009;=&#x2009;0.015) and the ratio of Bifidobacterium to total bacteria (p&#x2009;<&#x2009;0.001) decreased from VOPI 0 to VOPI 3. Significant differences in total bacteria (p&#x2009;<&#x2009;0.001) and S. mutans (p&#x2009;=&#x2009;0.018) were detected from VOPI 0 to VOPI 2. A difference in Bifidobacterium (p&#x2009;<&#x2009;0.001) was detected from VOPI 0 to VOPI 1.<br><br>CONCLUSION: Quantities of total bacteria (p&#x2009;<&#x2009;0.001), S. mutans (p&#x2009;=&#x2009;0.02) and ICDAS scores (p&#x2009;<&#x2009;0.001) and VOPI scores were positively correlated. Quantities of ratio of S. mutans to total bacteria (p&#x2009;=&#x2009;0.003) and ratio of Bifidobacterium to total bacteria (p&#x2009;<&#x2009;0.001) and VOPI scores and ICDAS scores (p&#x2009;<&#x2009;0.001) were negatively correlated.}, }
@article {pmid39714542, year = {2024}, author = {Zhang, K and Li, Q and Gong, C and Mao, H and Han, D}, title = {Inhibitory effect of andrographolide on the expression of key regulatory genes in Staphylococcus epidermidis biofilm formation.}, journal = {Journal of molecular histology}, volume = {56}, number = {1}, pages = {53}, pmid = {39714542}, issn = {1567-2387}, support = {No.: ZR2021QH055//Natural Science Foundation of Shandong Province/ ; No.: ZR2021QH055//Natural Science Foundation of Shandong Province/ ; No.: ZR2021QH055//Natural Science Foundation of Shandong Province/ ; No.: ZR2021QH055//Natural Science Foundation of Shandong Province/ ; No.: ZR2021QH055//Natural Science Foundation of Shandong Province/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Staphylococcus epidermidis/drug effects/genetics/physiology ; *Diterpenes/pharmacology ; *Gene Expression Regulation, Bacterial/drug effects ; Anti-Bacterial Agents/pharmacology ; Bacterial Proteins/genetics/metabolism ; Bacterial Adhesion/drug effects ; Genes, Regulator ; }, abstract = {The purpose of this study was to explore the inhibitory effect of andrographolide on the expression of key regulatory genes involved in the biofilm formation of Staphylococcus epidermidis (SE). Taking the film-producing strain Staphylococcus epidermidis SE1457 as the research object, the effect of andrographolide on the formation of Staphylococcus epidermidis biofilms was analyzed via crystal violet staining, and biofilm models of SE adhesion, aggregation and maturity were established in vitro. RT‒PCR was used to detect the effects of the expression of icaA-, atlE-, aap- and luxS-related genes of andrographolide on biofilm formation in SE. Congo red qualitative test to evaluate the ability of andrographolide to inhibit biofilm formation of Staphylococcus epidermidis. Compared with that of the control group, the light absorption value of the low- and high-concentration andrographolide groups was significantly lower, and the light absorption value of the high-concentration andrographolide group was significantly lower than that of the low-concentration andrographolide group. The levels of key genes involved in the adhesion, aggregation and maturation of icaA, atlE, aap and luxS in group C were greater than those in group B. The biofilm-forming ability of SE in group A was strong, and the colonies were obviously black. The colony in the direction of the arrow in group B was red, and the SE biofilm was inhibited. Most of the colonies in group C were red. SE biofilms were significantly inhibited. Andrographolide inhibits SE biofilm formation, and its mechanism may involve inhibition of the expression of the related genes icaA, atlE, aap and luxS.}, }
@article {pmid39714182, year = {2024}, author = {Willett, JLE and Dunny, GM}, title = {Insights into ecology, pathogenesis, and biofilm formation of Enterococcus faecalis from functional genomics.}, journal = {Microbiology and molecular biology reviews : MMBR}, volume = {}, number = {}, pages = {e0008123}, doi = {10.1128/mmbr.00081-23}, pmid = {39714182}, issn = {1098-5557}, abstract = {SUMMARYEnterococcus faecalis is a significant resident of the gastrointestinal tract of most animals, including humans. Although generally non-pathogenic in healthy hosts, this microbe is adept at the exploitation of compromises in host immune functions, resulting in life-threatening opportunistic infections whose treatments are complicated by a high degree of intrinsic and acquired resistance to antimicrobial chemotherapy. Historically, progress in enterococcal research was limited by a lack of experimental models that replicate natural infection pathways and the relevance of in vitro studies to the natural biology of the organism. In this review, we summarize the history of enterococcal research during the 20th and early 21st centuries and describe more recent genetic and genomic tools and screens developed to address challenges in the field. We also describe how the results of recent studies reveal the importance of previously uncharacterized enterococcal genes, and we provide examples of interesting determinants that have emerged as important contributors to enterococcal biology. These factors may also serve as targets for future vaccines and chemotherapeutic agents to combat life-threatening hospital infections.}, }
@article {pmid39712920, year = {2024}, author = {Tomasello, F and De Cesare, A and Valero Díaz, A}, title = {Training in quantitative microbial risk assessment of Listeria monocytogenes in processing chains: Quantification of biofilm-cells transfer integrating virulence and persistence factors.}, journal = {EFSA journal. European Food Safety Authority}, volume = {22}, number = {Suppl 1}, pages = {e221106}, pmid = {39712920}, issn = {1831-4732}, abstract = {Food safety is a global challenge, with nearly 1 in 10 people worldwide falling ill each year from consuming contaminated food. The risk is particularly high in ready-to-eat (RTE) products, which are consumed without further cooking to eliminate harmful microorganisms. To address this, the University of Cordoba and the University of Bologna, in the framework of the EU-FORA programme, developed a training programme focused on quantitative microbial risk assessment (QMRA) for Listeria monocytogenes in RTE food processing chains, a significant public health concern due to its association with severe foodborne illnesses. The programme aimed to train the fellow in advanced food microbiology techniques, predictive modelling and comprehensive QMRA methodologies. The fellow gained hands-on experience with predictive microbiology models applied to real-world scenarios, particularly RTE meat and fish products. Activities included developing predictive models for microbial growth and conducting challenge tests to evaluate Listeria behaviour in various foods. Emphasising data collection and statistical analysis, the fellowship explores the dynamics of Listeria within the food supply chain. A case study on sliced cooked ham demonstrates QMRA's application, using Monte Carlo simulations to estimate Listeria concentrations at consumption, ultimately informing risk management strategies. This initiative aimed to increase the number of food safety risk assessment experts in Europe, thereby enhancing public health outcomes related to foodborne diseases.}, }
@article {pmid39712885, year = {2024}, author = {Moshaverinia, M and Sahmeddini, S and Lavaee, F and Zareshahrabadi, Z and Zomorodian, K}, title = {Corrigendum to "Antimicrobial and Anti-Biofilm Activities of Thymus fallax Essential Oil against Oral Pathogens".}, journal = {BioMed research international}, volume = {2024}, number = {}, pages = {9797835}, pmid = {39712885}, issn = {2314-6141}, abstract = {[This corrects the article DOI: 10.1155/2022/9744153.].}, }
@article {pmid39711551, year = {2024}, author = {Bogyo, M and Upadhyay, T and Woods, E and Ahator, S and Julin, K and Faucher, F and Hollander, M and Pedowitz, N and Abegg, D and Hammond, I and Eke, I and Wang, S and Chen, S and Bennett, J and Jo, J and Lentz, C and Adibekian, A and Fellner, M}, title = {Covalent-fragment screening identifies selective inhibitors of multiple Staphylococcus aureus serine hydrolases important for growth and biofilm formation.}, journal = {Research square}, volume = {}, number = {}, pages = {}, pmid = {39711551}, issn = {2693-5015}, support = {R01 EB026332/EB/NIBIB NIH HHS/United States ; T32 GM141819/GM/NIGMS NIH HHS/United States ; }, abstract = {Staphylococcus aureus is a leading cause of bacteria-associated mortality worldwide. This is largely because infection sites are often difficult to localize and the bacteria forms biofilms which are not effectively cleared using classical antibiotics. Therefore, there is a need for new tools to both image and treat S. aureus infections. We previously identified a group of S. aureus serine hydrolases known as fluorophosphonate-binding hydrolases (Fphs), which regulate aspects of virulence and lipid metabolism. However, because their structures are similar and their functions overlap, it remains challenging to distinguish the specific roles of individual members of this family. In this study, we applied a high-throughput screening approach using a library of covalent electrophiles to identify inhibitors for FphB, FphE, and FphH. We identified inhibitors that irreversibly bind to the active-site serine residue of each enzyme with high potency and selectivity without requiring extensive medicinal chemistry optimization. Structural and biochemical analysis identified novel binding modes for several of the inhibitors. Selective inhibitors of FphH impaired both bacterial growth and biofilm formation while Inhibitors of FphB and FphE had no impact on cell growth and only limited impact on biofilm formation. These results suggest that all three hydrolases likely play functional, but non-equivalent roles in biofilm formation and FphH is a potential target for development of therapeutics that have both antibiotic and anti-biofilm activity. Overall, we demonstrate that focused covalent fragment screening can be used to rapidly identify highly potent and selective electrophiles targeting bacterial serine hydrolases. This approach could be applied to other classes of lipid hydrolases in diverse pathogens or higher eukaryotes.}, }
@article {pmid39711107, year = {2025}, author = {Tang, Q and Ye, W and Chandarajoti, K and Ge, R and Lv, S and Zhang, K and Han, X and Wang, C and Bai, H and Wang, X and Zhou, W}, title = {Discovery of xanthone-based nitric oxide donors targeting biofilm clearance.}, journal = {Archiv der Pharmazie}, volume = {358}, number = {1}, pages = {e2400793}, doi = {10.1002/ardp.202400793}, pmid = {39711107}, issn = {1521-4184}, support = {2023YFD1800800//National Key Research and Development Program of China/ ; U22A20518//National Natural Science Foundation of China/ ; 32171931//National Natural Science Foundation of China/ ; }, mesh = {*Biofilms/drug effects ; *Xanthones/pharmacology/chemistry/chemical synthesis ; Animals ; Mice ; *Staphylococcus aureus/drug effects/physiology ; *Nitric Oxide Donors/pharmacology/chemical synthesis/chemistry ; *Anti-Bacterial Agents/pharmacology/chemical synthesis/chemistry ; *Microbial Sensitivity Tests ; Staphylococcal Infections/drug therapy/microbiology ; Nitric Oxide/metabolism ; Structure-Activity Relationship ; Molecular Structure ; Disease Models, Animal ; Drug Discovery ; Humans ; }, abstract = {Bacteria biofilm infection seriously challenges clinical drug therapy. Nitric oxide (NO) was reported to disperse biofilm, eliminate bacteria resistance and kill bacteria. In this study, on the basis of membrane targeting of α-mangostin (α-MG) and the dispersion effect of NO on bacteria biofilms, we designed and synthesized 30 NO donors that α-MG was conjugated with a nitrobenzene or a nitrate and other four representative reference derivatives. Compound 23 with 2-chloro-4-nitrobenzoyl introduced in the position C6 of α-MG exhibited the prominent ability to eradicate Staphylococcous aureus biofilm, and a more long-lasting and stable bactericidal effect in vitro, and lower hemolytic activity over α-MG. Moreover, a mouse wound model infected by S. aureus biofilm supported the in vivo reduced bacterial burden closely associated with the NO release from compound 23 that exerted a dispersing effect on biofilms. Therefore, our design strategy can provide a promising and effective solution to intervene in biofilm infection with high specificity.}, }
@article {pmid39710928, year = {2024}, author = {Teymouri, S and Pourhajibagher, M and Bahador, A}, title = {Therapeutic Potential of Emodin: A Mini-Review of Its Anti-Biofilm and Antimicrobial Effects.}, journal = {Infectious disorders drug targets}, volume = {}, number = {}, pages = {}, doi = {10.2174/0118715265329198241105030008}, pmid = {39710928}, issn = {2212-3989}, abstract = {The resistance of biofilms to antimicrobial agents presents numerous challenges. The formation of biofilms leads to enhanced resistance to adverse environmental condi-tions, as well as to antimicrobial agents. Natural compounds have been of interest as po-tential therapeutic agents. Emodin, a natural anthraquinone compound, has recently at-tracted attention for its potential as a broad-spectrum antimicrobial agent. This ability could potentially help combat biofilm-associated infections and enhance the effectiveness of an-timicrobial therapies. This review was carried out to evaluate the effects of emodin on mi-crobial biofilms, determine its effectiveness in inhibiting and reducing biofilm formation, eradicate biofilms, and examine its antimicrobial effects. Our study shows that the use of emodin as an additional therapeutic agent in combating microbial biofilms holds consider-able promise. As researchers continue to investigate how emodin interacts with microbial biofilms, there is excitement about the potential applications of this natural compound in addressing biofilm-related issues. However, it is suggested to pay more attention to evalu-ating the effects of emodin on microbial biofilms in future studies.}, }
@article {pmid39710922, year = {2024}, author = {Pourhajibagher, M and Bahador, A}, title = {In vitro Anti-biofilm and Anti-adhesion Effects of Lactic Acid Bacteria- derived Biosurfactants against Streptococcus mutans.}, journal = {Infectious disorders drug targets}, volume = {}, number = {}, pages = {}, doi = {10.2174/0118715265336536241014072854}, pmid = {39710922}, issn = {2212-3989}, abstract = {INTRODUCTION: Biosurfactants are naturally occurring compounds with various ap-plications, biodegradable, non-toxic, and effective in different conditions. This study fo-cuses on the extraction and evaluation of biosurfactants produced by five strains of lactic acid bacteria [LAB] for their potential to inhibit biofilm formation and adhesion by Strep-tococcus mutans.<br><br>METHODS: The strains of LAB-producing biosurfactants such as Lactobacillus salivarius, L. acidophilus, L. plantarum, L. casei, and L. rhamnosus were confirmed by the hemolysis test. The presence of biosurfactants derived from LAB strains and their molecular compo-sition were confirmed, and their cellular toxicity, minimum inhibitory concentration [MIC], and minimum bactericidal concentration [MBC] were investigated. Ultimately, the anti-biofilm and anti-adhesive activities of LAB-derived biosurfactants against S. mutans were determined. Eventually, the effect of biosurfactants on the changes in gene expression associated with biofilm formation of S. mutans was assessed. All the LAB strains used in this study were biosurfactant producers. The LAB-derived bi-osurfactants exhibited no cytotoxicity towards the human gingival fibroblast [HGF] cell line. According to the results, the lowest and highest MIC values were observed in the biosurfactants derived from L. rhamnosus and L. plantarum at 0.78 mg/mL and 6.25 mg/mL, respectively. The MBC values for the biosurfactants derived from L. rhamnosus, L. casei, L. salivarius, L. acidophilus, and L. plantarum were 3.12, 3.12, 6.25, 12.5, and 12.5 mg/mL, respectively. The LAB-derived biosurfactants at MBC concentrations exhib-ited significant inhibitory effects on biofilm formation and adhesion of S. mutans [P<0.05]. The highest anti-biofilm and anti-adhesion activities were attributed to the biosurfactants derived from L. plantarum, which were not significantly different from the 0.2% chlorhex-idine as a positive control group [P>0.05]. Moreover, all biosurfactants could significantly decrease the gene expression level of gtfB [P>0.05].<br><br>RESULTS: The study found that LAB-derived biosurfactants exhibit significant anti-adhesion and anti-biofilm activities against S. mutans without any observed cellular toxicity towards HGF cells.<br><br>CONCLUSION: These promising bioactive compounds can be utilized as natural antimicrobial agents and biofilm inhibitors to prevent microbial biofilm formation and adhesion in vari-ous dental applications, offering a safe and effective alternative for controlling dental bio-films and improving oral health outcomes.}, }
@article {pmid39710670, year = {2024}, author = {Al-Madboly, LA and Aboulmagd, A and El-Salam, MA and Kushkevych, I and El-Morsi, RM}, title = {Microbial enzymes as powerful natural anti-biofilm candidates.}, journal = {Microbial cell factories}, volume = {23}, number = {1}, pages = {343}, pmid = {39710670}, issn = {1475-2859}, mesh = {*Biofilms/drug effects ; Bacteria/drug effects/enzymology ; Aspergillus niger/enzymology ; Anti-Bacterial Agents/pharmacology ; Glycoside Hydrolases/metabolism ; Carbohydrate Dehydrogenases/metabolism ; }, abstract = {Bacterial biofilms pose significant challenges, from healthcare-associated infections to biofouling in industrial systems, resulting in significant health impacts and financial losses globally. Classic antimicrobial methods often fail to eradicate sessile microbial communities within biofilms, requiring innovative approaches. This review explores the structure, formation, and role of biofilms, highlighting the critical importance of exopolysaccharides in biofilm stability and resistance mechanisms. We emphasize the potential of microbial enzymatic approaches, particularly focusing on glycosidases, proteases, and deoxyribonucleases, which can disrupt biofilm matrices effectively. We also delve into the importance of enzymes such as cellobiose dehydrogenase, which disrupts biofilms by degrading polysaccharides. This enzyme is mainly sourced from Aspergillus niger and Sclerotium rolfsii, with optimized production strategies enhancing its efficacy. Additionally, we explore levan hydrolase, alginate lyase, α-amylase, protease, and lysostaphin as potent antibiofilm agents, discussing their microbial origins and production optimization strategies. These enzymes offer promising avenues for combating biofilm-related challenges in healthcare, environmental, and industrial settings. Ultimately, enzymatic strategies present environmentally friendly solutions with high potential for biofilm management and infection control.}, }
@article {pmid39710222, year = {2025}, author = {Zheng, Y and Wang, M and Zhang, X and Wu, Z and Gao, L}, title = {A bacteria-responsive nanoplatform with biofilm dispersion and ROS scavenging for the healing of infected diabetic wounds.}, journal = {Acta biomaterialia}, volume = {193}, number = {}, pages = {545-558}, doi = {10.1016/j.actbio.2024.12.042}, pmid = {39710222}, issn = {1878-7568}, mesh = {*Biofilms/drug effects ; *Reactive Oxygen Species/metabolism ; *Wound Healing/drug effects ; *Anti-Bacterial Agents/pharmacology ; Animals ; *Pseudomonas aeruginosa/drug effects/physiology ; *Staphylococcus aureus/drug effects ; Free Radical Scavengers/pharmacology/chemistry ; Male ; Wound Infection/drug therapy/microbiology/pathology ; Nanoparticles/chemistry ; Diabetes Mellitus, Experimental/pathology ; Rats, Sprague-Dawley ; Mice ; Boronic Acids/chemistry/pharmacology ; Rats ; Humans ; }, abstract = {Delayed wound healing in patients with diabetes remains a major health challenge worldwide. Uncontrolled bacterial infection leads to excessive production of reactive oxygen species (ROS) and persistent inflammatory responses, which seriously hinder conventional physiological healing processes after injury. Biofilms, as protective barriers for bacteria, pose a critical obstacle to effective bacterial eradication. Herein, an innovative therapeutic nanoplatform with in situ antibacterial and antioxidant properties is developed for enhancing infected diabetic wound healing. The enrichment of phenylboronic acid (PBA) moieties on the nanoplatform enhances biofilm penetration, actively anchors and aggregates the enclosed bacteria through the "multivalent effect", with an anchoring efficiency as high as 80 %. Additionally, glycine moieties on the nanoplatform ensure spatial extensibility by charge repulsion, enabling targeted antibiotic release around bacteria. This precise antibacterial effect increases the bactericidal activities of the nanoplatform against S. aureus or P. aeruginosa by 25 % and 22 % respectively, effectively eliminating the bacteria and dispersing the biofilms. Furthermore, 3,4-dihydropyrimidin-2(1H)-one (DHPM) moieties act as ROS scavengers that alleviate oxidative stress and inflammatory responses, promoting tissue repair progression into the proliferative phase characterized by increased extracellular matrix deposition, angiogenesis, and granulation tissue formation, ultimately accelerating diabetic wound healing. Overall, this work presents an innovative bacterial response strategy for achieving in situ antibacterial and antioxidant effects in infected tissues and provides a promising therapeutic approach for treating infected diabetic wounds. STATEMENT OF SIGNIFICANCE: Infected diabetic wound management remains a major world health issue. Severe bacterial infection leads to excessive oxidative stress and persistent inflammatory response, which seriously hinders the wound healing process. As a protective barrier for bacteria, biofilms are a key obstacle to effective bacterial clearance. This study provides a bacteria-responsive nanoplatform for the healing of infected diabetic wounds. The nanoplatform not only exhibits improved biofilm penetration but also actively anchors the enclosed bacteria and enables targeted antibiotic release to disperse the biofilm. The DHPM moieties of the nanoplatform act as ROS scavengers which could alleviate inflammatory responses, promote tissue repair progression into the proliferative phase, and ultimately accelerate diabetic wound repair.}, }
@article {pmid39710209, year = {2024}, author = {Xu, M and Yu, S and Li, P and Chen, Y and Chen, Y and Pan, J and Deng, X and Hu, H}, title = {Tailored multilayer nanoparticles against resistant P. aeruginosa by disrupting the thickened mucus, dense biofilm and hyperinflammation.}, journal = {Journal of controlled release : official journal of the Controlled Release Society}, volume = {378}, number = {}, pages = {588-604}, doi = {10.1016/j.jconrel.2024.12.040}, pmid = {39710209}, issn = {1873-4995}, abstract = {Therapeutic challenges of chronic pulmonary infections caused by multidrug-resistant Pseudomonas aeruginosa (MDRP. aeruginosa) biofilms due to significantly enhanced antibiotic resistance. This resistance is driven by reduced outer membrane permeability, biofilm barriers, and excessive secretion of virulence factors. Thickened mucus in the airways exacerbates the problem by impeding antibiotic penetration, providing a breeding ground for biofilms, consequently aggravating infection. Moreover, biofilms recruit numerous immune cells, resulting in chronic inflammation and lung tissue damage. In turn, damaged airway further facilitates bacterial colonization and elevated mucus production. To thoroughly disintegrate the stubborn triad of "thickened mucus &amp; dense biofilm &amp; excessive inflammation" and address drug resistance, tailored multilayer nanoparticles (NPVC/PBIP NPs) were developed. NPVC/PBIP NPs were engineered through self-assembly of vanillin-chitosan amphiphilic polymer loading polymyxin B-linoleic acid ion pairs in. Then polyaspartic acid and N-acetylcysteine-ε-poly-l-lysine were coated by layer-by-layer on the surface of vanillin-chitosan NPs via electrostatic interactions. As expected, the NAC units on NPVC/PBIP NPs effectively thinned human clinical sputum and porcine sputum, resulting in rapid sputum penetration followed by biofilm permeation. NPVC/PBIP NPs achieved over 99 % eradication of mature biofilms in vitro. Furthermore, they effectively inhibited virulence factors production and bacteria re-adhesion (biofilm reformation) while exhibiting superior anti-inflammatory and antioxidant activities. In a chronic pulmonary infection model, NPVC/PBIP NPs remarkably thinned airway mucus, reduced bacterial burden by 99.7 %, alleviated inflammatory cell infiltration, and minimized lung tissue damage. In summary, the NPVC/PBIP NPs represent a novel and promising strategy to manage MDRP. aeruginosa biofilms associated infections by disintegrating the stubborn triad of "thickened mucus &amp; dense biofilm &amp; excessive inflammation".}, }
@article {pmid39708762, year = {2025}, author = {Zhou, R and Huang, X and Ni, Y and Ma, Z and Wei, H and Jin, Q and Ding, Z}, title = {Physicochemical behavior and ecological risk of biofilm-mediated microplastics in aquatic environments.}, journal = {Aquatic toxicology (Amsterdam, Netherlands)}, volume = {279}, number = {}, pages = {107209}, doi = {10.1016/j.aquatox.2024.107209}, pmid = {39708762}, issn = {1879-1514}, mesh = {*Biofilms/drug effects ; *Microplastics/toxicity ; *Water Pollutants, Chemical/toxicity ; }, abstract = {The prevalence of microplastics (MPs) in aquatic environments has become the core of environmental pollution. In recent years, the inevitable biological aging process of MPs in natural environments has attracted researchers' attention. Such biofilm-mediated MPs, colonized by microorganisms, affect the physicochemical behavior and potential ecological risks of MPs. Therefore, it is critical to understand the impact of MPs' biofilm formation on the environmental fate and toxicity of MPs. This review presented a comprehensive discussion of the impact of biofilm formation on unique carrier effects and toxicological effects of MPs in aquatic environments. First, the biofilm formation process on MPs, the compositions of microorganisms in biofilm and the factors influencing biofilm formation were briefly summarized. Second, the sorption of pollutants and enrichment of antibiotic resistance genes onto biofilm-mediated MPs were discussed. Third, the potential effects of biofilm-mediated MPs on gut microbiota were analyzed. Finally, gaps in the field that require further investigations were put forward. This review emphasized that biofilm-mediated MPs have higher environmental risks and ecotoxicity, which is helpful in providing new insights for pollution prevention and control of new pollutant MPs.}, }
@article {pmid39708744, year = {2025}, author = {Gao, J and Ju, Z and Yang, Q and Zhou, X}, title = {Exploring different effects of biofilm formation and natural organic matter adsorption on the properties of three typical microplastics in the freshwater.}, journal = {The Science of the total environment}, volume = {958}, number = {}, pages = {178156}, doi = {10.1016/j.scitotenv.2024.178156}, pmid = {39708744}, issn = {1879-1026}, mesh = {*Biofilms ; *Microplastics ; *Water Pollutants, Chemical ; Adsorption ; *Fresh Water/chemistry ; Polyethylene/chemistry ; Humic Substances ; Polyvinyl Chloride/chemistry ; Hydrophobic and Hydrophilic Interactions ; Polyethylene Terephthalates/chemistry ; Environmental Monitoring ; }, abstract = {Microplastics entering the aqueous environment are susceptible to the surrounding environmental processes, including biofilm formation and natural organic matter (NOM) adsorption, which significantly alters their properties and environmental fate. In this study, polyethylene (PE), polyvinyl chloride (PVC) and polyethylene terephthalate (PET) microplastics were respectively incubated in the untreated and disinfected freshwater to investigate the different effects of biofilm formation and only NOM adsorption on the properties of microplastics. The results showed that the total amount of fouling biomass driven by biofilm formation was markedly higher than that of NOM adsorption. The changes in microplastic surface morphologies and special surface area dominated by biofilm formation and NOM adsorption were different; biofilm formation induced various shaped bacteria and a dense layer of extracellular polymeric substances adhering on microplastic surfaces with the decreased special surface area, whereas NOM adsorption mainly resulted in the obvious pores, cracks and winkles and the increased special surface area, indicating the initial degradation of microplastics. Moreover, both biofilm formation and NOM adsorption could reduce the hydrophobicity of three microplastics. The decreased trends of the hydrophobicity of microplastics were closely related to the amount of fouling biomass in a linear relationship with different influenced coefficients (slope a), subsequently verifying that NOM adsorption played a key role in the alternation of the hydrophobicity of microplastics. Surface chemical characterization by FTIR and 3D-EEMs presented the generation of additional functional groups and components on the microplastic surface attributed to the biofilm formation and NOM adsorption in different extent and sequence. This study provides more detailed information about the different effects of biofilm formation and NOM adsorption on the properties of microplastics in the aqueous environment.}, }
@article {pmid39708620, year = {2025}, author = {Wang, L and Zhang, C and Liu, Y and Qiu, Y and Wanyan, D and Liu, J and Cheng, G and Lin, P and Huang, X}, title = {Achieving mainstream nitrogen removal by partial nitrification and anammox in the carriers-coupled membrane aerated biofilm reactor.}, journal = {Water research}, volume = {271}, number = {}, pages = {123000}, doi = {10.1016/j.watres.2024.123000}, pmid = {39708620}, issn = {1879-2448}, mesh = {*Bioreactors ; *Biofilms ; *Nitrification ; *Nitrogen/metabolism ; Waste Disposal, Fluid/methods ; Ammonium Compounds/metabolism ; Oxidation-Reduction ; Membranes, Artificial ; }, abstract = {The integration of partial nitrification-anammox (PN/A) into membrane-aerated biofilm reactor (MABR) is a promisingly energy-efficient and high-efficiency technology for nitrogen removal. The inhibition of nitrite oxidizing bacteria (NOB) remains as the most significant challenge for its development. In our investigation, we proposed a novel process to integrate carriers to MABR (CMABR), which combined the carriers enriched with anaerobic ammonium-oxidizing bacteria (AnAOB) and partial nitrifying MABR system. The effect of different hydraulic retention time (HRT) was explored in CMABR and it showed that the nitrogen removal rate of CMABR could reach more than 200 g-N/(m[3]·d) at an HRT of 3 h The increase of NOB activity was witnessed when the residual NH4[+]-N concentration was lower than 5 mg-N/L. Finally, the higher nitrogen removal rate and successful PN/A can be achieved by optimized condition through the operation of two-stage CMABRs with 30 % of carriers filling ratio and a total HRT of 6 h Superior NH4[+]-N removal efficiency (97 %) and total nitrogen removal efficiency (81 %) were reached compared with other MABR for PN/A processes. The CMABR exerted the special advantage that significant AnAOB attached on the carriers, rather than only on the membrane biofilm, thus it was beneficial to maintain the activity of ammonia oxidizing bacteria (AOB) and improve the nitrogen removal rate and effluent quality. This investigation provides creative and significant perspectives for the design and operation of PN/A processes in the future MABR applications.}, }
@article {pmid39708379, year = {2025}, author = {Kaksonen, AH and Wylie, J and Morgan, MJ and Walsh, T and Tjandraatmadja, G and Barry, K and Gonzalez, D and Goodman, N and Vanderzalm, J and Dillon, P and Sidhu, J and Puzon, GJ}, title = {Impact of stormwater on biofilm density and microbial community composition in water distribution networks.}, journal = {Water research}, volume = {272}, number = {}, pages = {122989}, doi = {10.1016/j.watres.2024.122989}, pmid = {39708379}, issn = {1879-2448}, mesh = {*Biofilms ; Water Supply ; Water Microbiology ; Drinking Water/microbiology ; Rain ; Bacteria ; Groundwater/microbiology/chemistry ; }, abstract = {Harvesting of stormwater and injecting it into aquifers for storage and recovery during high water demand periods is a promising technology for augmenting conventional water reserves. However, little has been known on how stormwater impacts the biofouling of water distribution infrastructure. This study evaluated the effect on harvested and limestone aquifer treated stormwater on biofilm formation in a pilot distribution pipe network compared to an identical drinking water pipe rig. Coupons made of cement, copper and polyvinyl chloride (PVC) pipe materials were installed to each pipe rig and exposed to stormwater or drinking water. The total cell counts determined by flow cytometry on the pilot rig coupons were in the order of 10[5] to 10[7] cells/cm[2] for both source waters and showed some variation over the duration of the study. The culturable cell counts were somewhat higher for stormwater exposed coupons than for coupons in mains water rig. The total number of thermotolerant coliforms was notably higher on coupons exposed to stormwater than on those exposed to mains water. Considerable differences were observed in the bacterial and eukaryotic communities on coupons made of various materials and exposed to mains water and stormwater using pyrosequencing. Moreover, seasonal variations were observed in community composition and diversity. A number of bacterial and eukaryotic families and genera harbouring potential human pathogens were detected in both mains water and stormwater systems, with larger numbers of genera observed in the latter indicating a potentially increased risk of exposure to pathogens with stormwater. The stormwater system also harboured sulfur reducers, and a greater diversity of iron oxidisers. A number of bacterial genera that contribute to nitrogen cycling were observed in both mains water and stormwater systems. A number of bacteria grazing eukaryotes were detected, indicating that the biofilm communities are quite dynamic and the abundance of bacteria is able to support higher level eukaryotes.}, }
@article {pmid39707959, year = {2024}, author = {}, title = {Correction to: Poly-Ether-Ether-Ketone versus dead-soft coaxial bonded retainers: a randomized clinical trial. Part 2: periodontal health and microbial biofilm assessment.}, journal = {European journal of orthodontics}, volume = {47}, number = {1}, pages = {}, doi = {10.1093/ejo/cjae080}, pmid = {39707959}, issn = {1460-2210}, }
@article {pmid39707459, year = {2024}, author = {Del Rey, YC and Kitzinger, K and Lund, MB and Schramm, A and Meyer, RL and Wagner, M and Schlafer, S}, title = {pH-FISH: coupled microscale analysis of microbial identity and acid-base metabolism in complex biofilm samples.}, journal = {Microbiome}, volume = {12}, number = {1}, pages = {266}, pmid = {39707459}, issn = {2049-2618}, support = {doi.org.1055776/COE7//Austrian Science Fund (FWF) for the Cluster of Excellence "Microbiomes drive Planetary Health"/ ; doi.org.1055776/COE7//Austrian Science Fund (FWF) for the Cluster of Excellence "Microbiomes drive Planetary Health"/ ; }, mesh = {*Biofilms/growth &amp; development ; *In Situ Hybridization, Fluorescence/methods ; Hydrogen-Ion Concentration ; Humans ; *Streptococcus/metabolism/genetics ; Veillonella/metabolism ; Dental Caries/microbiology ; Microbiota ; Bacteria/metabolism/classification/genetics ; }, abstract = {BACKGROUND: Correlative structural and chemical imaging of biofilms allows for the combined analysis of microbial identity and metabolism at the microscale. Here, we developed pH-FISH, a method that combines pH ratiometry with fluorescence in situ hybridization (FISH) in structurally intact biofilms for the coupled investigation of microbial acid metabolism and biofilm composition. Careful biofilm handling and modified sample preparation procedures for FISH allowed preservation of the three-dimensional biofilm structure throughout all processing and imaging steps. We then employed pH-FISH to investigate the relationship between local biofilm pH and the distribution of acid-producing (streptococci) and acid-consuming (Veillonella spp.) bacteria in dental biofilms from healthy subjects and caries-active patients.<br><br>RESULTS: The relative abundance of streptococci correlated with low biofilm pH at the field-of-view level, while the opposite trend was observed for Veillonella spp. These results suggest that clusters of streptococci contribute to the formation of acidic pockets inside dental biofilms, whereas Veillonella spp. may have a protective role against biofilm acidification.<br><br>CONCLUSIONS: pH-FISH combines microscale mapping of biofilm pH in real time with structural imaging of the local microbial architecture, and is a powerful method to explore the interplay between biofilm composition and metabolism in complex biological systems. Video Abstract.}, }
@article {pmid39706307, year = {2025}, author = {Zhang, B and Liu, J and Cai, C and Zhou, Y}, title = {Membrane photobioreactor for biogas capture and conversion - Enhanced microbial interaction in biofilm.}, journal = {Bioresource technology}, volume = {418}, number = {}, pages = {131999}, doi = {10.1016/j.biortech.2024.131999}, pmid = {39706307}, issn = {1873-2976}, mesh = {*Biofilms ; *Biofuels/microbiology ; *Photobioreactors/microbiology ; *Microalgae/metabolism ; *Membranes, Artificial ; *Methane/metabolism ; Microbial Interactions/physiology ; Carbon Dioxide/metabolism ; }, abstract = {The urgency to mitigate greenhouse gas emissions has driven interest in sustainable biogas utilization. This study investigates a 1 L enclosed membrane photobioreactor (MPBR) using a microalgae-methanotroph coculture for biogas capture. Operating with a hydraulic and solid retention time of 7 days and a biogas loading rate of 2.7 L /day, the introduction of gas membrane module increased CO2-C and CH4-C uptake rates by 12 % and 50 %, respectively. Biofilm formation on the membrane surface enhanced system performance, with imaging analyses revealing methanotroph predominantly located near the membrane surface and photosynthetic microorganisms distributed throughout. Metagenomic analysis showed shifts in key metabolic pathways, including increased abundance of soluble methane monooxygenase genes and enhanced vitamin B synthesis in the biofilm. These findings highlight the spatial organization and metabolic interactions in methanotroph-microalgae coculture system, providing insights into the role of membrane-induced biofilms in improving MPBR performance for sustainable biogas utilization.}, }
@article {pmid39706277, year = {2024}, author = {Golan, N and Parizat, A and Tabachnikov, O and Barnea, E and Olsen, WP and Otzen, DE and Landau, M}, title = {Resilience and charge-dependent fibrillation of functional amyloid: Interactions of Pseudomonas biofilm-associated FapB and FapC amyloids.}, journal = {The Journal of biological chemistry}, volume = {301}, number = {2}, pages = {108096}, pmid = {39706277}, issn = {1083-351X}, abstract = {FapC and FapB are biofilm-associated amyloids involved in the virulence of Pseudomonas and other bacteria. We herein demonstrate their exceptional thermal and chemical resilience, suggesting that their biofilm structures might withstand standard sterilization, thereby contributing to the persistence of Pseudomonas aeruginosa infections. Our findings also underscore the impact of environmental factors on functional amyloid in Pseudomonas (Fap) proteins, suggesting that orthologs in different Pseudomonas strains adapt to specific environments and roles. Challenging previous assumptions about a simple nucleation role for FapB in promoting FapC aggregation, the study shows a significant influence of FapC on FapB aggregation. The interaction between these FapB and FapC is intricate: FapB stabilizes FapC fibrils, while FapC slows down FapB fibrillation but can still serve as a cross-seeding template. This complex interplay is the key to understanding their roles in bacterial biofilms. Furthermore, the study highlights distinct differences between Fap and Escherichia coli's CsgA (curli) amyloid, where CsgB assumes a simple unidirectional role in nucleating CsgA fibrillation, emphasizing the importance of a comprehensive understanding of various amyloid systems. This knowledge is vital for developing effective intervention strategies against bacterial infections and leveraging the unique properties of these amyloids in technological applications such as novel bionanomaterials or protective coatings.}, }
@article {pmid39705953, year = {2025}, author = {Sun, H and Ju, X and Wang, H and Ma, X and Shi, B}, title = {Ammonia nitrogen affects bacterial virulence and conditional pathogenic bacterial growth by regulating biofilm microbial metabolism and EPS secretion in laboratory scale distribution systems.}, journal = {The Science of the total environment}, volume = {958}, number = {}, pages = {178150}, doi = {10.1016/j.scitotenv.2024.178150}, pmid = {39705953}, issn = {1879-1026}, mesh = {*Biofilms ; *Ammonia/metabolism ; *Bacteria/metabolism ; Extracellular Polymeric Substance Matrix/metabolism ; Nitrogen/metabolism ; Virulence ; Drinking Water/microbiology ; Virulence Factors/metabolism ; Water Supply ; }, abstract = {The control of conditional pathogenic bacteria and inhibition of their virulence factors (VFs) in drinking water distribution systems (DWDSs) is vital for drinking water safety. This study adopted two groups of DWDSs to investigate how ammonia nitrogen affects bacterial VFs and conditional pathogenic bacterial growth in biofilms. Our results indicated that Acidimicrobium (95,916.62 ± 119.24 TPM), Limnohabitans (30,338.81 ± 139.14 TPM), and Sediminibacterium (10,658.01 ± 48.94 TPM) were predominant in the biofilm bacterial community of DWDSs with NH3-N addition. Under these conditions, the abundances of various bacterial metabolites, such as L-glutamate (1.45-fold), 2-oxoglutarate (1.24-fold), pyruvate (2.10-fold), and adenosine monophosphate (AMP, 5.29-fold), were significantly upregulated, which suggested the upregulation of amino acid, carbohydrate, nucleotide, lipid, pyrimidine and purine metabolism. These metabolic pathways accelerated extracellular polymeric substance (EPS) secretion. The protein concentration in EPS also increased to 187.59 ± 0.58 μg/cm[2]. The increased EPS secretion promoted the amide I CO group of the EPS protein to interact with the surface of the DWDSs, thus enhancing the ability of bacteria (especially conditional pathogenic bacteria) to adhere to the pipe surface to form biofilms. Due to EPS protection, the abundance of the adherence subtype of VFs and the plate counts of Pseudomonas aeruginosa increased to 5912.8 ± 21.89 TPM and 655.78 ± 27.10 CFU/cm[2], respectively. Therefore, NH3-N in DWDSs increased bacterial VFs levels and promoted the growth of some conditional pathogenic bacteria by regulating biofilm microbial metabolic pathways and EPS secretion, ultimately impacting the interaction between EPS and the pipe surface.}, }
@article {pmid39705926, year = {2025}, author = {Nabawy, A and Chattopadhyay, AN and Makabenta, JMV and Hassan, MA and Yang, J and Park, J and Jiang, M and Jeon, T and Im, J and Rotello, VM}, title = {Cationic conjugated polymers with tunable hydrophobicity for efficient treatment of multidrug-resistant wound biofilm infections.}, journal = {Biomaterials}, volume = {316}, number = {}, pages = {123015}, pmid = {39705926}, issn = {1878-5905}, support = {R01 AI134770/AI/NIAID NIH HHS/United States ; R01 DK121351/DK/NIDDK NIH HHS/United States ; }, mesh = {*Biofilms/drug effects ; *Polymers/chemistry ; Animals ; *Hydrophobic and Hydrophilic Interactions ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Cations/chemistry ; *Drug Resistance, Multiple, Bacterial/drug effects ; Mice ; Wound Infection/drug therapy/microbiology ; Microbial Sensitivity Tests ; }, abstract = {Biofilm-associated infections arising from antibiotic-resistant bacteria pose a critical challenge to global health. We report the generation of a library of cationic conjugated poly(phenylene ethynylene) (PPE) polymers featuring trimethylammonium terminated sidechains with tunable hydrophobicity. Screening of the library identified an amphiphilic polymer with a C11 hydrophobic spacer as the polymer with the highest antimicrobial efficacy against biofilms in the dark with excellent selectivity. These polymers are highly fluorescent, allowing label-free monitoring of polymer-bacteria/biofilm interactions. The amphiphilic conjugated polymer penetrated the biofilm matrix in vitro and eradicated resident bacteria through membrane disruption. This C11 polymer was likewise effective in an in vivo murine model of antibiotic-resistant wound biofilm infections, clearing >99.9 % of biofilm colonies and efficient alleviation of biofilm-associated inflammation. The results demonstrate the therapeutic potential of the fluorescent conjugated polymer platform as a multi-modal antimicrobial and imaging tool, surpassing conventional antimicrobial strategies against resilient biofilm infection.}, }
@article {pmid39705888, year = {2025}, author = {Pant, K and Palmer, J and Flint, S}, title = {Evaluation of single and multispecies biofilm formed in the static and continuous systems.}, journal = {International journal of food microbiology}, volume = {429}, number = {}, pages = {111030}, doi = {10.1016/j.ijfoodmicro.2024.111030}, pmid = {39705888}, issn = {1879-3460}, mesh = {*Biofilms/growth &amp; development/drug effects ; *Listeria monocytogenes/physiology/growth &amp; development/drug effects ; *Pseudomonas fluorescens/physiology/growth &amp; development ; *Staphylococcus aureus/physiology/drug effects/growth &amp; development ; *Sodium Hypochlorite/pharmacology ; *Stainless Steel ; *Disinfectants/pharmacology ; Food Microbiology ; Colony Count, Microbial ; }, abstract = {Biofilms consisting of multiple species of bacteria compared to biofilms of single species are common in natural environments including food contact surfaces. The objective of this study was to understand the biofilm formation and the efficiency of sodium hypochlorite (50 ppm/5 mins) on the single and multiple species biofilm of Pseudomonas fluorescens, Staphylococcus aureus, and Listeria monocytogenes formed on stainless steel surfaces in static and continuous systems. The cell concentration of Listeria in the dual and triple species biofilm in the continuous system (7.3-8.4 log CFU/cm[2]) was higher compared to the static system (4.7-4.9 log CFU/cm[2]) while the concentration remained consistent in the single species biofilm (6.4-6.7 log CFU/cm[2]) for both systems. Biofilm formed in the static system was significantly (p < 0.001) more susceptible to sodium hypochlorite than biofilm formed in the continuous system. This observation agrees with the exopolysaccharide concentration which was found to be higher in the continuous system (8.0-15.6 μg/cm[2]) than in the static system (3.2-6.3 μg/cm[2]) indicating a positive correlation between EPS production and sanitizer resistance. Epifluorescence microscopy images showed the formation of interstitial voids within the three-species biofilm and filaments in the single and dual species Listeria biofilms in the continuous system which were absent in the static system. Overall, results showed that the biofilm formation and sanitizer resistance vary due to multispecies interaction and the presence of flow and should be considered an important variable in multispecies sanitizer resistance studies.}, }
@article {pmid39705014, year = {2025}, author = {Aftab, H and Samudio, J and Wang, G and Le, L and Soni, RK and Donegan, RK}, title = {Heme alters biofilm formation in Mycobacterium abscessus.}, journal = {Microbiology spectrum}, volume = {13}, number = {2}, pages = {e0241524}, pmid = {39705014}, issn = {2165-0497}, support = {G-1021873.01//Burroughs Wellcome Fund (BWF)/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Heme/metabolism ; *Mycobacterium abscessus/drug effects/growth &amp; development/physiology ; Humans ; *Cystic Fibrosis/microbiology ; *Iron/metabolism ; Mycobacterium Infections, Nontuberculous/microbiology ; Lung/microbiology ; Anti-Bacterial Agents/pharmacology ; }, abstract = {Mycobacterium abscessus (Mabs) is commonly found in the cystic fibrosis (CF) lung. During infection, Mabs can form biofilms in the lung which reduce both the ability of the immune response to clear infection and the effectiveness of antibiotic therapy. In the CF lung, heme and hemoglobin levels are increased and may provide both iron and heme to Mabs cells. In this work, we show that exogenous heme altered Mabs biofilm formation and measured the effects of exogenous heme on protein level and metabolism in Mabs. Our findings suggest that heme impacts iron homeostasis in Mabs and affects other aspects of its metabolism, highlighting the potential role of heme as a critical nutrient for Mabs growth and biofilm formation.IMPORTANCEMycobacterium abscessus (Mabs) is commonly found in the cystic fibrosis (CF) lung, where Mabs can form biofilms that can reduce the efficacy of antibiotics. During infection, the CF lung can have more than 10 times the extracellular heme than that of a healthy lung. We have found that extracellular heme can change the way Mabs cells grow and form biofilms, which may have implications for pathogenesis.}, }
@article {pmid39704863, year = {2024}, author = {Cui, L and Chen, S and Cao, X and Zhang, X and Huang, X and Shibata, T and Yang, Y and Shi, L and Zhao, C and Wang, S and Yang, S}, title = {Simultaneous removal of heavy metals and inorganic nitrogen by using the biofilm of Marichromatium gracile YL28.}, journal = {World journal of microbiology &amp; biotechnology}, volume = {41}, number = {1}, pages = {14}, pmid = {39704863}, issn = {1573-0972}, support = {201505026//National Marine Public Industry Research/ ; 2018J0149//Natural Science Foundation of Fujian Province/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Metals, Heavy/metabolism ; *Nitrogen/metabolism ; *Biodegradation, Environmental ; *Water Pollutants, Chemical/metabolism ; Adsorption ; Chromatiaceae/metabolism ; Extracellular Polymeric Substance Matrix/metabolism/chemistry ; }, abstract = {Heavy metal and nitrogen contaminations are serious concerns in aquatic environments. Marichromatium gracile YL28, a marine purple sulfur bacterium, has shown great potential as a bioremediation agent for removing inorganic nitrogen from marine water. This study further investigated its ability to simultaneously absorb heavy metals, including Pb(II), Cu(II), Cd(II) and Cr(VI), and remove inorganic nitrogen. The contributions of photopigment and extracellular polymeric substances (EPS) in the YL28 biofilm to heavy metal adsorption and tolerance were also evaluated. The YL28 biofilm demonstrated higher adsorption efficiencies for heavy metal ions than planktonic cells. A high level of EPS was detected in the biofilm. The effects of four heavy metal on the inhibition of photopigment synthesis showed that high concentrations of Cu(II) greatly inhibited the production of BChl a and Car. The adsorption efficiencies of Pb(II), Cu(II), Cd(II), and Cr(VI) in the YL28 biofilm reactor reached 86.59%, 72.94%, 80.06%, and 95.95%, respectively. Elevated concentrations of heavy metal ions only marginally impeded ammonia nitrogen removal; they impacted neither nitrite and nitrate removals nor hindered the simultaneous elimination of three inorganic nitrogen compounds. Coupled with their ability to remove inorganic nitrogen, the high adsorption capacity and tolerance of YL28 biofilms toward heavy metal suggest a promising solution for mitigating metal pollutants.}, }
@article {pmid39704631, year = {2024}, author = {Sinha, A and Taneja, S and Shetty, DC and Bhalla, VK}, title = {Efficacy of Antimicrobial Peptide GH12 on a Multispecies Endodontic Biofilm Model: An In-vitro Study.}, journal = {European endodontic journal}, volume = {9}, number = {4}, pages = {411-417}, pmid = {39704631}, issn = {2548-0839}, mesh = {*Biofilms/drug effects ; *Porphyromonas gingivalis/drug effects ; Humans ; *Enterococcus faecalis/drug effects ; *Microbial Sensitivity Tests/methods ; *Fusobacterium nucleatum/drug effects ; Streptococcus mutans/drug effects ; In Vitro Techniques ; Microscopy, Electron, Scanning/methods ; Antimicrobial Peptides/pharmacology ; Dental Pulp Cavity/microbiology ; }, abstract = {OBJECTIVE: This study aimed to evaluate the antibacterial efficacy of different concentrations of GH12 on a simulated multispecies biofilm comprising Enterococcus faecalis, Streptococcus mutans, Fusobacterium nucleatum and Porphyromonas gingivalis.<br><br>METHODS: Single rooted teeth were decoronated, cut into 1.5 mm sections to obtain dentine discs which were randomly allocated into five groups: (n=12 each), Group 1: Phosphate Buffered Solution (PBS) - negative control, Group II: 5% Sodium hypochlorite (NaOCl) - positive control, Group III: Minimum Inhibitory Concentration (MIC) of GH12, Group IV: 2x MIC of GH12, Group V: 4x MIC of GH12. Colony forming units, Crystal violet assay and scanning electron microscopy examinations were performed. One-way ANOVA and Turkey's test were applied for statistical analysis using the SPSS software version 22.0.<br><br>RESULTS: Group II (NaOCl) showed maximum reduction in bacterial load followed by Group V (GH12 16mg/mL) with no statistically significant difference (p=1.000). On comparing the mean CFU reduction, the maximum reduction was identified for S. mutans and the least was for P. gingivalis. There was marked erosion observed in the NaOCl group whereas the GH12 group showed no erosive changes in the morphology and no bacterial colonies was identified.<br><br>CONCLUSION: The findings revealed that GH12 at higher concentrations inhibits and disrupts the growth of multispecies endodontic biofilm comparable to NaOCl but without erosive effects to the dentine, further highlighting its potential to be used as an antimicrobial solution. (EEJ-2023-10-147).}, }
@article {pmid39703182, year = {2025}, author = {Kaur, N and De, M}, title = {Shape and Size Dependent Antimicrobial and Anti-biofilm Properties of Functionalized MoS2.}, journal = {ACS infectious diseases}, volume = {11}, number = {1}, pages = {249-261}, doi = {10.1021/acsinfecdis.4c00860}, pmid = {39703182}, issn = {2373-8227}, mesh = {*Molybdenum/pharmacology/chemistry ; *Biofilms/drug effects ; *Disulfides/pharmacology/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; *Microbial Sensitivity Tests ; *Nanostructures/chemistry ; Staphylococcus aureus/drug effects ; Quantum Dots/chemistry ; Particle Size ; }, abstract = {Bacterial resistance, accelerated by the misuse of antibiotics, remains a critical concern for public health, promoting an ongoing exploration for cost-effective and safe antibacterial agents. Recently, there has been significant focus on various nanomaterials for the development of alternative antibiotics. Among these, molybdenum disulfide (MoS2) has gained attention due to its unique chemical, physical, and electronic properties, as well as its semiconducting nature, biocompatibility, and colloidal stability, positioning it as a promising candidate for biomedical research. The impact of the shape and size of MoS2 nanomaterials on the antibacterial activity remains largely unexplored. In this study, we investigated the effect of the shape and size of MoS2 nanomaterials, such as quantum dots, nanoflowers, and nanosheets, on antimicrobial and anti-biofilm activity. As we had established earlier, functionalization with positively charged thiol ligands can enhance colloidal stability, biocompatibility, and antibacterial efficacy; we functionalized all targeted nanomaterials. Our results revealed that functionalized MoS2 quantum dots (F-MQDs) exhibited superior activity compared to functionalized MoS2 nanoflowers (F-MNFs) and functionalized MoS2 nanosheets (F-MNSs) against Staphylococcus aureus (SA), both drug-resistant (methicillin) and nonresistant strains. We observed very low minimum inhibitory concentration (MIC, 30 ng/mL) for F-MQDs. The observed trend in antibacterial efficacy was as follows: F-MQDs > F-MNFs ≥ F-MNSs. We explored the relevant mechanism related to the antibacterial activity where the balance between membrane depolarization and internalization plays the determining role. Furthermore, F-MQDs show enhanced anti-biofilm activity compared to F-MNFs and F-MNSs against mature MRSA biofilms. Due to the superior antibacterial and anti-biofilm activity of F-MQDs, we extended their application to wound healing. This study will help us to develop other appropriate surface modified nanomaterials for antibacterial and anti-biofilm activity for further applications such as antibacterial coatings, water disinfection, and wound healing.}, }
@article {pmid39702763, year = {2024}, author = {Beckman, RL and Cella, E and Azarian, T and Rendueles, O and Fleeman, RM}, title = {Diverse polysaccharide production and biofilm formation abilities of clinical Klebsiella pneumoniae.}, journal = {NPJ biofilms and microbiomes}, volume = {10}, number = {1}, pages = {151}, pmid = {39702763}, issn = {2055-5008}, support = {R00 AI163295/AI/NIAID NIH HHS/United States ; R00AI163295//Division of Intramural Research, National Institute of Allergy and Infectious Diseases (Division of Intramural Research of the NIAID)/ ; ANR 22 CE20 00181 BETinCAP//Agence Nationale de la Recherche (French National Research Agency)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Klebsiella pneumoniae/genetics/growth &amp; development/physiology ; Humans ; *Polysaccharides, Bacterial/metabolism/biosynthesis/genetics ; *Klebsiella Infections/microbiology ; Phenotype ; Virulence ; Gene Expression Regulation, Bacterial ; Genotype ; Drug Resistance, Multiple, Bacterial/genetics ; }, abstract = {Klebsiella pneumoniae infections have become a growing threat for human health. The lack of understanding of the relationship between antibiotic resistance, mucoviscosity, and biofilm formation impedes our abilities to effectively predict K. pneumoniae infection outcomes. The Multidrug-Resistant Organism Repository and Surveillance Network offers a unique opportunity into the genetic and phenotypic variabilities in the K. pneumoniae isolates. To this end, we compared the genetic profiles of these isolates with the phenotypic biofilm formation, percent mucoviscosity, and growth rates. There was a significant phenotype-genotype correlation with decreased biofilm formation and an insertion sequence in the transcriptional activator of the type III fimbrial system. Interestingly, the most mucoid strains in the populations were lacking the genetic element regulating the mucoid phenotype and three of these isolates were able to form robust biofilms. The combination of phenotypic, genomic, and image analyses revealed an intricate relation between growth, mucoviscosity and specific virulence-associated genetic determinants.}, }
@article {pmid39701350, year = {2025}, author = {Sheng, M and Liu, J and Zhou, Y and Shao, S}, title = {Effect of metal ions on moving bed biofilm reactor (MBBR) for nitrogen removal in wastewater: Performance characteristics, flocculation efficiency and bacterial community.}, journal = {Environmental research}, volume = {267}, number = {}, pages = {120655}, doi = {10.1016/j.envres.2024.120655}, pmid = {39701350}, issn = {1096-0953}, mesh = {*Biofilms ; *Bioreactors/microbiology ; *Nitrogen/metabolism ; *Wastewater/chemistry/microbiology ; *Flocculation ; *Waste Disposal, Fluid/methods ; Metals ; Water Pollutants, Chemical/analysis ; Bacteria/metabolism ; }, abstract = {Advanced operational moving bed biofilm reactor (MBBR) has demonstrated to achieve simultaneous sludge yield minimization and pollutants removal. However, effect of different metal ions on MBBR performance for nutrients removal in wastewater under low carbon to nitrogen ratio is still unclear. Fate of NH4[+]-N and NO3[-]-N by MBBR were explored under the influence of Mn(II), Cu(II), and Fe(II) at carbon to nitrogen ratio of 5. The result showed that Mn(II) and Fe(II) significantly improved the NH4[+]-N and TN removal with a removal ratio of 71.0% and 80.5%, and 77.8% and 87.5% compared to the absence of added metal ions, and Cu(II) reduced the nitrogen removal. Biofilm characteristics including extracellular polymeric substances (EPS), electron transport system activity, and reactive oxygen species were investigated. The result indicated that both Mn(II) and Fe(II) enhanced the extracellular polymeric substances activity, electron transfer, and flocculation efficiency and hydrophilicity of biofilm. Furthermore, nitrification and denitrification processes of MBBR were further evaluated by X-ray photoelectron spectroscopy, fourier transform infrared reflection, cyclic voltammetry, differential pulse voltammetry, and Tafel curves. The result revealed that the main functional groups (e.g., C=O, C-O, and O-C=O bonds), and manganese and iron cycling might be involved in the nitrogen and metal ions removal. Finally, microbial community and co-occurrence network of biofilm were studied, showing that Proteobacteria and Bacteroidetes were identified as the dominant phyla for nitrogen and metal ions removal. This study aimed to provide the technical support for the startup and engineering applications of MBBR in wastewater treatment.}, }
@article {pmid39700628, year = {2025}, author = {Voglauer, EM and Alteio, LV and Pracser, N and Thalguter, S and Quijada, NM and Wagner, M and Rychli, K}, title = {Listeria monocytogenes colonises established multispecies biofilms and resides within them without altering biofilm composition or gene expression.}, journal = {Microbiological research}, volume = {292}, number = {}, pages = {127997}, doi = {10.1016/j.micres.2024.127997}, pmid = {39700628}, issn = {1618-0623}, mesh = {*Biofilms/growth &amp; development ; *Listeria monocytogenes/genetics/physiology ; *Gene Expression Regulation, Bacterial ; Gene Expression Profiling ; Food Microbiology ; Bacterial Proteins/genetics/metabolism ; }, abstract = {Listeria (L.) monocytogenes can survive for extended periods in the food producing environment. Here, biofilms possibly provide a niche for long-term survival due to their protective nature against environmental fluctuations and disinfectants. This study examined the behaviour of a L. monocytogenes ST121 isolate in a multispecies biofilm composed of Pseudomonas (P.) fragi, Brochothrix (B.) thermosphacta, and Carnobacterium (C.) maltaromaticum, previously isolated from a meat processing facility. The composition of the biofilm community and matrix, and transcriptional activity were analysed. L. monocytogenes colonised the multispecies biofilm, accounting for 6.4 % of all total biofilm cells after six hours. Transcriptomic analysis revealed 127 significantly up-regulated L. monocytogenes genes compared to the inoculum, including motility, chemotaxis, iron, and protein transport related genes. When comparing the differentially expressed transcripts within the multispecies biofilm with and without L. monocytogenes, only a cadmium/zinc exporting ATPase gene in C. maltaromaticum was significantly upregulated, while the other 9313 genes in the biofilm community showed no significant differential expression. We further monitored biofilm development over time (6, 24 hours and 7 days). P. fragi remained the dominant species, while L. monocytogenes was able to survive in the multispecies biofilm accounting for 2.4 % of total biofilm cells after 7 days, without any significant changes in its abundance. The presence of L. monocytogenes did neither alter the biofilm community nor its matrix composition (amount of extracellular DNA, carbohydrates, and protein). Our data indicate that L. monocytogenes resides in multispecies biofilms, potentially increasing survival against cleaning and disinfection in food processing environments, supporting persistence.}, }
@article {pmid39697559, year = {2024}, author = {}, title = {Functional Study of desKR: A Lineage-Specific Two-Component System Positively Regulating Staphylococcus Aureus Biofilm Formation [Retraction].}, journal = {Infection and drug resistance}, volume = {17}, number = {}, pages = {5579-5580}, doi = {10.2147/IDR.S509159}, pmid = {39697559}, issn = {1178-6973}, abstract = {[This retracts the article DOI: 10.2147/IDR.S485049.].}, }
@article {pmid39696637, year = {2024}, author = {Zarenezhad, E and Behmard, E and Karami, R and Behrouz, S and Marzi, M and Ghasemian, A and Soltani Rad, MN}, title = {The antibacterial and anti-biofilm effects of novel synthetized nitroimidazole compounds against methicillin-resistant Staphylococcus aureus and carbapenem-resistant Escherichia coli and Klebsiella pneumonia in vitro and in silico.}, journal = {BMC chemistry}, volume = {18}, number = {1}, pages = {244}, pmid = {39696637}, issn = {2661-801X}, abstract = {The antibiotic resistance and biofilm formation by bacterial pathogens has led to failure in infections elimination. This study aimed to assess the antibacterial and anti-biofilm properties of novel synthesized nitroimidazole compounds (8a-8o). In this study, nitroimidazole compounds were synthesized via the A3 coupling reaction of sample substrates in the presence of copper-doped silica cuprous sulfate (CDSCS). Fifteen and two carbapenemase producing Escherichia coli and Klebsiella pneumonia (CP-E. coli and CP-K. pneumonia, respectively) and one methicillin-resistant Staphylococcus aureus (MRSA) and one methicillin-susceptible S. aureus (MSSA) plus standard strain of each isolate were included. The antibacterial effects of these compounds demonstrated that the lowest minimum inhibitory and bactericidal concentrations (MIC/MBC, respectively) levels corresponded to compound 8g against S. aureus (1/2 µg/mL) and K. pneumonia (8/32 µg/mL) standard and clinical strains and confirmed by in silico assessment. This was comparable to those of metronidazole being 32-128 µg/mL against K. pneumonia and 32-64 µg/mL against S. aureus. In comparison to metronidazole, against CP-E. coli, compounds 8i and 8m had significantly higher antibacterial effects (p < 0.001) and against CP-K. pneumonia, compounds 8a-8j and 8l-8o had significantly higher (p < 0.0001) antibacterial effects. Compound 8g exhibited significantly higher antibacterial effects against MSSA and compounds 8b (p < 0.001), 8c (p < 0.001), 8d (p < 0.001), 8e (p < 0.001) and 8g (p < 0.0001) exerted significantly higher antibacterial effects than metronidazole against MRSA. Moreover, potential anti-biofilm effects was corresponded to compounds 8a, 8b, 8c, 8e, 8f, 8g, 8i, 8k, 8m and 8n. Considering the antibacterial and anti-biofilm effects of novel synthesized compounds evaluated in this study, further assessments is warranted to verify their properties in vivo and clinical trials in the future.}, }
@article {pmid39695832, year = {2024}, author = {Portas, A and Carriot, N and Barry-Martinet, R and Ortalo-Magné, A and Hajjoul, H and Dormoy, B and Culioli, G and Quillien, N and Briand, JF}, title = {Shear stress controls prokaryotic and eukaryotic biofilm communities together with EPS and metabolomic expression in a semi-controlled coastal environment in the NW Mediterranean Sea.}, journal = {Environmental microbiome}, volume = {19}, number = {1}, pages = {109}, pmid = {39695832}, issn = {2524-6372}, abstract = {While waves, swells and currents are important drivers of the ocean, their specific influence on the biocolonization of marine surfaces has been little studied. The aim of this study was to determine how hydrodynamics influence the dynamics of microbial communities, metabolic production, macrofoulers and the associated vagile fauna. Using a field device simulating a shear stress gradient, a multi-scale characterization of attached communities (metabarcoding, LC-MS, biochemical tests, microscopy) was carried out for one month each season in Toulon Bay (northwestern Mediterranean). Shear stress appeared to be the primary factor influencing biomass, EPS production and community structure and composition. Especially, the transition from static to dynamic conditions, characterized by varying shear stress intensities, had a more pronounced effect on prokaryotic and eukaryotic beta-diversity than changes in shear stress intensity or seasonal physico-chemical parameters. In static samples, mobile microbe feeders such as arthropods and nematodes were predominant, whereas shear stress favored the colonization of sessile organisms and heterotrophic protists using the protective structure of biofilms for growth. The increase in shear stress resulted in a decrease in biomass but an overproduction of EPS, specifically exopolysaccharides, suggesting an adaptive response to withstand shear forces. Metabolite analysis highlighted the influence of shear stress on community dynamics. Specific metabolites associated with static conditions correlated positively with certain bacterial and algal groups, indirectly indicating reduced grazer control with increasing shear stress.}, }
@article {pmid39695822, year = {2024}, author = {Abera, GB and Trømborg, E and Solli, L and Walter, JM and Wahid, R and Govasmark, E and Horn, SJ and Aryal, N and Feng, L}, title = {Biofilm application for anaerobic digestion: a systematic review and an industrial scale case.}, journal = {Biotechnology for biofuels and bioproducts}, volume = {17}, number = {1}, pages = {145}, pmid = {39695822}, issn = {2731-3654}, support = {336972//Norges Forskningsr&#xe5;d/ ; 257622//Norges Forskningsr&#xe5;d/ ; }, abstract = {Biofilm is a syntrophic community of microorganisms enveloped by extracellular polymeric substances and displays remarkable adaptability to dynamic environments. Implementing biofilm in anaerobic digestion has been widely investigated and applied as it promotes microbial retention time and enhances the efficiency. Previous studies on anaerobic biofilm primarily focused on application in wastewater treatment, while its role has been significantly extended to accelerate the degradation of lignocellulosic biomass, improve gas-liquid mass transfer for biogas upgrading, or enhance resistance to inhibitors or toxic pollutants. This work comprehensively reviewed the current applications of biofilm in anaerobic digestion and focused on impacting factors, optimization strategies, reactor set-up, and microbial communities. Moreover, a full-scale biofilm reactor case from Norway is also reported. This review provides a state of-the- art insight on the role of biofilm in anaerobic digestion.}, }
@article {pmid39695365, year = {2024}, author = {Narimisa, N and Khoshbayan, A and Gharaghani, S and Razavi, S and Jazi, FM}, title = {Inhibitory effects of nafcillin and diosmin on biofilm formation by Salmonella Typhimurium.}, journal = {BMC microbiology}, volume = {24}, number = {1}, pages = {522}, pmid = {39695365}, issn = {1471-2180}, mesh = {*Biofilms/drug effects ; *Salmonella typhimurium/drug effects/physiology/genetics ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology ; *Nafcillin/pharmacology ; Microscopy, Electron, Scanning ; Bacterial Proteins/genetics/metabolism ; Gene Expression Regulation, Bacterial/drug effects ; }, abstract = {OBJECTIVE: The foodborne pathogen Salmonella enterica serovar Typhimurium causes self-limiting gastroenteritis in humans and is difficult to eliminate due to its ability to adhere to surfaces and form biofilms that exhibit high resistance to antimicrobial agents. To explore alternative strategies for biofilm treatment, it is essential to investigate novel agents that inhibit Salmonella biofilms.<br><br>METHOD: In this study, we investigated the minimum biofilm inhibitory concentrations (MBICs) and minimum biofilm eradication concentrations (MBECs) of nafcillin and diosmin, both previously identified as Lon protease inhibitors, against biofilms formed by S. Typhimurium. Furthermore, we examined the expression of genes associated with the type II toxin-antitoxin system to enhance our understanding of the impact of these inhibitors.<br><br>RESULTS: The findings indicated a strong antibiofilm effect of nafcillin, with MBIC and MBEC values of 8&#xa0;&#xb5;g/mL and 32&#xa0;&#xb5;g/mL, respectively. These results were confirmed by field emission scanning electron microscopy (FE-SEM), which showed that biofilm formation was reduced in the presence of nafcillin. Additionally, it revealed morphological changes in the bacteria within the nafcillin-treated biofilms. Furthermore, gene expression analyses demonstrated a significant reduction in the expression of type II TA system genes following treatment with nafcillin and diosmin.<br><br>CONCLUSION: This study highlights the effectiveness of nafcillin in disrupting the biofilms of S. Typhimurium. These results suggest promising avenues for the development of novel therapeutic strategies targeting biofilms associated with S. Typhimurium.}, }
@article {pmid39691803, year = {2024}, author = {Sanesi, L and Puca, V and Caponio, VCA and Pinti, M and Balice, G and Femminella, B and Paolantonio, M and Cela, I and Kaushik, NK and Choi, EH and Grande, R and Sardella, E and Perrotti, V}, title = {Disinfection of dental root canals by cold atmospheric plasma: a systematic review and meta-analysis of dental biofilm.}, journal = {Frontiers in oral health}, volume = {5}, number = {}, pages = {1483078}, pmid = {39691803}, issn = {2673-4842}, abstract = {AIM: The intricate structure of the tooth root canals has a role in the colonization and biofilm formation in hidden areas that are hardly reached by standard endodontic treatments. This review aims at summarizing data from in vitro and ex vivo studies for a better understanding of the application of cold atmospheric plasma (CAP) for the disinfection of dental root canals.<br><br>METHODS: PubMed, Scopus, and Web of Science databases were screened. Characteristics of the included studies were extracted, and a meta-analysis on ex vivo studies was carried out to evaluate the effect of CAP on colony forming unit assay of Enterococcus faecalis (E. faecalis). The study was performed following the PRISMA 2020 guidelines.<br><br>RESULTS: A total of 31 studies fulfilled the selection criteria. Only 2 investigations reported an indirect plasma treatment, 28 trials used direct CAP administration, while 1 study applied both methods. Most of the studies were conducted on E. faecalis using as carrier gas Helium or Argon alone or in combination with Oxygen as well air. A considerable heterogeneity among studies was found regarding treatments which varied for source type, settings, and protocols of application. Despite this, CAP showed effectiveness in reducing E. faecalis colony forming unit with a standardized mean difference of 4.51, 95% C.I.&#x2009;=&#x2009;2.55-6.48, p-value&#x2009;<&#x2009;0.001.<br><br>CONCLUSION: The data demonstrated the antimicrobial effect of direct CAP application against microorganisms. In-vitro studies showed an effect that depended on the time and distance of treatment, while the meta-analysis performed on ex vivo studies showed that the effect of CAP was independent of time and distance.<br><br>https://doi.org/10.17605/OSF.IO/BJ59V, identifier OSF registries.}, }
@article {pmid39690480, year = {2025}, author = {Sun, H and Jiang, L and Chen, J and Kang, C and Yan, J and Ma, S and Zhao, M and Guo, H and Yang, B}, title = {Genomic island-encoded LmiA regulates acid resistance and biofilm formation in enterohemorrhagic Escherichia coli O157:H7.}, journal = {Gut microbes}, volume = {17}, number = {1}, pages = {2443107}, pmid = {39690480}, issn = {1949-0984}, mesh = {*Escherichia coli O157/genetics/physiology/drug effects ; *Biofilms/growth &amp; development/drug effects ; *Genomic Islands ; *Escherichia coli Proteins/genetics/metabolism ; *Gene Expression Regulation, Bacterial ; *Acids/pharmacology/metabolism ; Escherichia coli Infections/microbiology ; Humans ; Glutamate Decarboxylase ; Membrane Proteins ; }, abstract = {Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is an important intestinal pathogen that causes severe foodborne diseases. We previously demonstrated that the genomic island-encoded regulator LmiA activates the locus of enterocyte effacement (LEE) genes to promote EHEC O157:H7 adherence and colonization in the host intestine. However, whether LmiA is involved in the regulation of any other biological processes in EHEC O157:H7 remains largely unexplored. Here, we compared global gene expression differences between the EHEC O157:H7 wild-type strain and an lmiA mutant strain using RNA-seq technology. Genes whose expression was affected by LmiA were identified and classified using the Cluster of Orthologous Groups (COG) database. Specifically, the expression of acid resistance genes (including gadA, gadB, and gadC) was significantly downregulated, whereas the transcript levels of biofilm-related genes (including Z_RS00105, yadN, Z_RS03020, and fdeC) were increased, in the ΔlmiA mutant compared to the EHEC O157:H7 wild-type strain. Further investigation revealed that LmiA enhanced the acid resistance of EHEC O157:H7 by directly activating the transcription of gadA and gadBC. In contrast, LmiA reduced EHEC O157:H7 biofilm formation by indirectly repressing the expression of biofilm-related genes. Furthermore, LmiA-mediated regulation of acid resistance and biofilm formation is highly conserved and widespread among EHEC and enteropathogenic E. coli (EPEC). Our findings provide essential insight into the regulatory function of LmiA in EHEC O157:H7, particularly its role in regulating acid resistance and biofilm formation.}, }
@article {pmid39690297, year = {2024}, author = {Ding, J and Yan, Z and Peng, L and Li, J and Yang, F and Zheng, D}, title = {Inhibitory effects of berberine on fungal growth, biofilm formation, virulence, and drug resistance as an antifungal drug and adjuvant with prospects for future applications.}, journal = {World journal of microbiology &amp; biotechnology}, volume = {41}, number = {1}, pages = {5}, pmid = {39690297}, issn = {1573-0972}, mesh = {Animals ; Humans ; *Antifungal Agents/pharmacology/therapeutic use ; *Berberine/pharmacology/therapeutic use ; *Biofilms/drug effects/growth &amp; development ; *Drug Resistance, Fungal/drug effects ; *Fungi/drug effects/growth &amp; development/metabolism/pathogenicity ; Microbial Sensitivity Tests ; Mycoses/drug therapy/microbiology ; Virulence/drug effects ; Virulence Factors/antagonists &amp; inhibitors/metabolism ; }, abstract = {Berberine (BBR), an isoquinoline alkaloid found in medicinal plants such as Coptidis rhizoma, Berberis sp., and Hydrastis canadensis, is a distinctive compound known for its dual ability to exhibit broad-spectrum antifungal activity while offering beneficial effects to the host. These attributes make it a highly valuable candidate for antifungal therapy and as an antibiotic adjuvant. This review provides a comprehensive evaluation of BBR's antifungal properties, focusing on its in vitro and in vivo activity, underlying mechanisms, and its influence on fungal pathogenicity, including virulence, biofilm formation, and resistance. Additionally, the antifungal potential of BBR extracts, derivatives, and nanoformulations is examined in detail. BBR demonstrates fungicidal effects through multiple mechanisms. It targets critical fungal components such as mitochondria, cell membranes, and cell walls, while also inhibiting enzymatic activity and transcription processes. Furthermore, it suppresses the expression of virulence factors, effectively diminishing fungal pathogenicity. Beyond its direct antifungal activity, BBR exerts beneficial effects on the host by modulating gut microbiota, thereby bolstering host defenses against fungal infections and reducing potential adverse effects. BBR's interaction with conventional antifungal drugs presents a unique complexity, particularly in the context of resistance mechanisms. When used in combination therapies, conventional antifungal drugs enhance the intracellular accumulation of BBR, thereby amplifying its antifungal potency as the primary active agent. These synergistic effects position BBR as a promising candidate for combination strategies, especially in addressing drug-resistant fungal infections and persistent biofilms. As antifungal resistance and biofilm-associated infections continue to rise, the multifaceted properties of BBR and its advanced formulations highlight their significant therapeutic potential. However, the scarcity of robust in vivo and clinical studies limits a full understanding of its efficacy and safety profile. To bridge this gap, future investigations should prioritize well-designed in vivo and clinical trials to thoroughly evaluate the therapeutic effectiveness and safety of BBR in diverse clinical settings. This approach could pave the way for its broader application in combating fungal infections.}, }
@article {pmid39689163, year = {2024}, author = {Yan, X and Liao, H and Wang, C and Huang, C and Zhang, W and Guo, C and Pu, Y}, title = {An improved bacterial single-cell RNA-seq reveals biofilm heterogeneity.}, journal = {eLife}, volume = {13}, number = {}, pages = {}, pmid = {39689163}, issn = {2050-084X}, support = {31970089//National Natural Science Foundation of China/ ; 2021YFC2701602//National Key Research and Development Program of China/ ; 2022CFA077//Science Fund for Distinguished Young Scholars of Hunan Province/ ; 2042022dx0003//Fundamental Research Funds for the Central Universities/ ; GZNL2024A01023//Major Project of Guangzhou National Laboratory/ ; 202001BB050005//Natural Science Foundation of Yunnan Province/ ; }, mesh = {*Biofilms/growth &amp; development ; *Single-Cell Analysis/methods ; *RNA-Seq/methods ; RNA, Bacterial/genetics ; Cyclic GMP/analogs &amp; derivatives/metabolism ; RNA, Ribosomal/genetics ; Escherichia coli/genetics/physiology ; Bacteria/genetics/classification ; Sequence Analysis, RNA/methods ; Single-Cell Gene Expression Analysis ; }, abstract = {In contrast to mammalian cells, bacterial cells lack mRNA polyadenylated tails, presenting a hurdle in isolating mRNA amidst the prevalent rRNA during single-cell RNA-seq. This study introduces a novel method, ribosomal RNA-derived cDNA depletion (RiboD), seamlessly integrated into the PETRI-seq technique, yielding RiboD-PETRI. This innovative approach offers a cost-effective, equipment-free, and high-throughput solution for bacterial single-cell RNA sequencing (scRNA-seq). By efficiently eliminating rRNA reads and substantially enhancing mRNA detection rates (up to 92%), our method enables precise exploration of bacterial population heterogeneity. Applying RiboD-PETRI to investigate biofilm heterogeneity, distinctive subpopulations marked by unique genes within biofilms were successfully identified. Notably, PdeI, a marker for the cell-surface attachment subpopulation, was observed to elevate cyclic diguanylate (c-di-GMP) levels, promoting persister cell formation. Thus, we address a persistent challenge in bacterial single-cell RNA-seq regarding rRNA abundance, exemplifying the utility of this method in exploring biofilm heterogeneity. Our method effectively tackles a long-standing issue in bacterial scRNA-seq: the overwhelming abundance of rRNA. This advancement significantly enhances our ability to investigate the intricate heterogeneity within biofilms at unprecedented resolution.}, }
@article {pmid39688690, year = {2024}, author = {Bai, XR and Liu, PX and Wang, WC and Jin, YH and Wang, Q and Qi, Y and Zhang, XY and Sun, WD and Fang, WH and Han, XG and Jiang, W}, title = {TssL2 of T6SS2 is required for mobility, biofilm formation, wrinkly phenotype formation, and virulence of Vibrio parahaemolyticus SH112.}, journal = {Applied microbiology and biotechnology}, volume = {108}, number = {1}, pages = {537}, pmid = {39688690}, issn = {1432-0614}, support = {32473039//the Natural Science Foundation of China/ ; 21ZR147700//the Shanghai Natural Science Foundation of China/ ; 17ZR1447200//the Shanghai Natural Science Foundation of China/ ; 31702277//the National Natural Science Foundation of China/ ; 21N31901000//the Shanghai Science and Technology Commission Research Project/ ; 2020JB07//Basic Public Welfare Research Program of Zhejiang Province/ ; }, mesh = {*Biofilms/growth &amp; development ; *Vibrio parahaemolyticus/genetics/pathogenicity/metabolism/physiology ; Animals ; Virulence ; Mice ; *Vibrio Infections/microbiology ; *Type VI Secretion Systems/genetics/metabolism ; *Bacterial Adhesion ; Phenotype ; Bacterial Proteins/genetics/metabolism ; Virulence Factors/genetics/metabolism ; Gene Deletion ; Gene Expression Regulation, Bacterial ; Mice, Inbred BALB C ; Macrophages/microbiology ; }, abstract = {Type VI secretion system 2 (T6SS2) of Vibrio parahaemolyticus is required for cell adhesion and autophagy in macrophages; however, other phenotypes conferred by this T6SS have not been thoroughly investigated. We deleted TssL2, a key component of T6SS2 assembly, to explore the role of the T6SS2 in environmental adaptation and virulence. TssL2 deletion reduced Hcp2 secretion, suggesting that TssL2 played an important role in activity of functional T6SS2. We found that TssL2 was necessary for cell aggregation, wrinkly phenotype formation, and participates in motility and biofilm formation by regulating related genes, suggesting that TssL2 was essential for V. parahaemolyticus to adapt changing environments. In addition, this study demonstrated TssL2 significantly affected adhesion, cytotoxicity, bacterial colonization ability, and mortality in mice, even the levels of the proinflammatory cytokines IL-6 and IL-8, suggesting that TssL2 was involved in bacterial virulence and immunity. Proteome analysis revealed that TssL2 significantly affected the expression of 163 proteins related to ABC transporter systems, flagellar assembly, biofilm formation, and multiple microbial metabolism pathways, some of which supported the effect of TssL2 on the different phenotypes of V. parahaemolyticus. Among them, the decreased expression of the T3SS1 and T2SS proteins was confirmed by the results of gene transcription, which may be the main reason for the decrease in cytotoxicity. Altogether, these findings further our understanding of T6SS2 components on environmental adaption and virulence during bacterial infection. KEY POINTS: • The role of T6SS2 in V. parahaemolyticus was far from clear. • TssL2 participates in cell aggregation, wrinkly phenotype formation, motility, and biofilm formation. • TssL2 is essential for cell bacterial colonization, cytotoxicity, virulence, and proinflammatory cytokine production.}, }
@article {pmid39688594, year = {2025}, author = {Donmez, HG and Sahal, G and Beksac, MS}, title = {Microbial cell-type-based grouping model as a potential indicator of cervicovaginal flora prone to biofilm formation.}, journal = {Biotechnic &amp; histochemistry : official publication of the Biological Stain Commission}, volume = {100}, number = {1}, pages = {17-22}, doi = {10.1080/10520295.2024.2439447}, pmid = {39688594}, issn = {1473-7760}, mesh = {*Biofilms ; Female ; Humans ; *Vagina/microbiology ; *Microbiota/physiology ; Cervix Uteri/microbiology ; Adult ; }, abstract = {Cervicovaginal (CV) microbiota is critical for the well-being of host. We investigated the relationship between the ratio of Lactobacilli (LB) and cocci/coccobacilli (C/CB)-type microbial cells with biofilm formation of CV mixed cultures of women with no inflammation/infection or any epithelial abnormalities in Pap-stained smears Group 1 (G1) corresponds to the flora with LB-type cells alone, whereas G2 corresponds to the LB-dominated flora. G3 contains balanced LB and C/CB cells and G4 is dominated with C/CB. G5 corresponds to a flora with C/CB-type cells alone. Biofilm formation of CV mixed cultures was assessed by crystal violet binding assay and optical density (OD)≥0.8 were defined as biofilm producers. G1 and G3 exist in higher frequencies compared to the other smear groups. However, although the frequency of G5 dominated with C/CB-type cells were the lowest (4%); biofilm formation in that group was observed in the highest frequency (42.9%). The least biofilm formation frequency was observed in G3 smears with balanced flora (1%). Biofilm formation in healthy CV flora increases when there becomes an imbalance between LB and C/CB-type cells and an increase in C/CB-type cells. Our approach may enable early detection of vaginal dysbiosis in healthy flora prone to biofilm-associated CV infections such as bacterial vaginosis (BV).}, }
@article {pmid39688394, year = {2025}, author = {Pang, LM and Zeng, G and Chow, EWL and Xu, X and Li, N and Kok, YJ and Chong, SC and Bi, X and Gao, J and Seneviratne, CJ and Wang, Y}, title = {Sdd3 regulates the biofilm formation of Candida albicans via the Rho1-PKC-MAPK pathway.}, journal = {mBio}, volume = {16}, number = {2}, pages = {e0328324}, pmid = {39688394}, issn = {2150-7511}, support = {OFIRG/0072/2018//MOH | National Medical Research Council (NMRC)/ ; OFIRG21jun-0058//MOH | National Medical Research Council (NMRC)/ ; OFIRG23Jul-0077//MOH | National Medical Research Council (NMRC)/ ; }, mesh = {*Candida albicans/genetics/physiology/enzymology ; *Biofilms/growth &amp; development ; *rho GTP-Binding Proteins/genetics/metabolism ; *Fungal Proteins/genetics/metabolism ; *Gene Expression Regulation, Fungal ; *Protein Kinase C/metabolism/genetics ; Chitin/metabolism ; Cell Wall/metabolism/genetics ; MAP Kinase Signaling System ; Signal Transduction ; Mitogen-Activated Protein Kinases/genetics/metabolism ; Humans ; }, abstract = {Candida albicans, the most frequently isolated fungal pathogen in humans, forms biofilms that enhance resistance to antifungal drugs and host immunity, leading to frequent treatment failure. Understanding the molecular mechanisms governing biofilm formation is crucial for developing anti-biofilm therapies. In this study, we conducted a genetic screen to identify novel genes that regulate biofilm formation in C. albicans. One identified gene is ORF19.6693, a homolog of the Saccharomyces cerevisiae SDD3 gene. The sdd3∆/∆ mutant exhibited severe defects in biofilm formation and significantly reduced chitin content in the cell wall. Overexpression of the constitutively active version of the Rho1 GTPase Rho1[G18V], an upstream activator of the protein kinase C (PKC)-mitogen-activated protein kinase (MAPK) cell-wall integrity pathway, rescued these defects. Affinity purification, mass spectrometry, and co-immunoprecipitation revealed Sdd3's physical interaction with Bem2, the GTPase-activating protein of Rho1. Deletion of SDD3 significantly reduced the amount of the active GTP-bound form of Rho1, thereby diminishing PKC-MAPK signaling and downregulating chitin synthase genes CHS2 and CHS8. Taken together, our studies identify a new biofilm regulator, Sdd3, in C. albicans that modulates Rho1 activity through its inhibitory interaction with Bem2, thereby regulating the PKC-MAPK pathway to control chitin biosynthesis, which is critical for biofilm formation. As an upstream component of the pathway and lacking a homolog in mammals, Sdd3 has the potential to serve as an antifungal target for biofilm infections.IMPORTANCEThe human fungal pathogen Candida albicans is categorized as a critical priority pathogen on the World Health Organization's Fungal Priority Pathogens List. A key virulence attribute of this pathogen is its ability to form biofilms on the surfaces of indwelling medical devices. Fungal cells in biofilms are highly resistant to antifungal drugs and host immunity, leading to treatment failure. This study conducted a genetic screen to discover novel genes that regulate biofilm formation. We found that deletion of the SDD3 gene caused severe biofilm defects. Sdd3 negatively regulates the Rho1 GTPase, an upstream activator of the protein kinase C-mitogen-activated protein kinase pathway, through direct interaction with Bem2, the GTPase-activating protein of Rho1, resulting in a significant decrease in chitin content in the fungal cell wall. This chitin synthesis defect leads to biofilm formation failure. Given its essential role in biofilm formation, Sdd3 could serve as an antifungal target for biofilm infections.}, }
@article {pmid39687463, year = {2024}, author = {Shaikh, S and McKay, G and Mackey, HR}, title = {Light intensity effects on bioproduct recovery from fuel synthesis wastewater using purple phototrophic bacteria in a hybrid biofilm-suspended growth system.}, journal = {Biotechnology reports (Amsterdam, Netherlands)}, volume = {44}, number = {}, pages = {e00863}, pmid = {39687463}, issn = {2215-017X}, abstract = {This research looked at how three different light intensities (1600, 4300, and 7200 lx) affect the biomass development, treatment of fuel synthesis wastewater and the recovery of valuable bioproducts between biofilm and suspended growth in a purple-bacteria enriched photobioreactor. Each condition was run in duplicate using an agricultural shade cloth as the biofilm support media in a continuously mixed batch reactor. The results showed that the highest chemical oxygen demand (COD) removal rate (56.8 ± 0.9 %) was found under the highest light intensity (7200 lx), which also led to the most biofilm formation and highest biofilm biomass production (1225 ± 95.7 mg). The maximum carotenoids (Crts) and bacteriochlorophylls (BChls) content occurred in the suspended growth of the 7200 lx reactor. BChls decreased with light intensity in suspended growth, while in biofilm both Crts and BChls were relatively stable between light conditions, likely due to an averaging effect as biofilm thickened at higher light intensity. Light intensity did not affect protein content of the biomass, however, biofilm showed a lower average (41.2 % to 43.7 %) than suspended biomass (45.4 % to 47.7 %). For polyhydroxybutyrate (PHB) the highest cell concentration in biofilm occurred at 1600 lx (11.4 ± 2.4 %), while for suspended growth it occurred at 7200 lx (22.7 ± 0.3 %), though total PHB productivity remained similar between reactors. Shading effects from the externally located biofilm could explain most variations in bioproduct distribution. Overall, these findings suggest that controlling light intensity can effectively influence the treatment of fuel synthesis wastewater and the recovery of valuable bioproducts in a biofilm photobioreactor.}, }
@article {pmid39684519, year = {2024}, author = {Markowska, K and Szymanek-Majchrzak, K and Pituch, H and Majewska, A}, title = {Understanding Quorum-Sensing and Biofilm Forming in Anaerobic Bacterial Communities.}, journal = {International journal of molecular sciences}, volume = {25}, number = {23}, pages = {}, pmid = {39684519}, issn = {1422-0067}, mesh = {*Quorum Sensing ; *Biofilms/growth &amp; development ; Bacteria, Anaerobic/physiology ; Humans ; Signal Transduction ; Gene Expression Regulation, Bacterial ; }, abstract = {Biofilms are complex, highly organized structures formed by microorganisms, with functional cell arrangements that allow for intricate communication. Severe clinical challenges occur when anaerobic bacterial species establish long-lasting infections, especially those involving biofilms. These infections can occur in device-related settings (e.g., implants) as well as in non-device-related conditions (e.g., inflammatory bowel disease). Within biofilms, bacterial cells communicate by producing and detecting extracellular signals, particularly through specific small signaling molecules known as autoinducers. These quorum-sensing signals are crucial in all steps of biofilm formation: initial adhesion, maturation, and dispersion, triggering gene expression that coordinates bacterial virulence factors, stimulates immune responses in host tissues, and contributes to antibiotic resistance development. Within anaerobic biofilms, bacteria communicate via quorum-sensing molecules such as N-Acyl homoserine lactones (AHLs), autoinducer-2 (AI-2), and antimicrobial molecules (autoinducing peptides, AIPs). To effectively combat pathogenic biofilms, understanding biofilm formation mechanisms and bacterial interactions is essential. The strategy to disrupt quorum sensing, termed quorum quenching, involves methods like inactivating or enzymatically degrading signaling molecules, competing with signaling molecules for binding sites, or noncompetitively binding to receptors, and blocking signal transduction pathways. In this review, we comprehensively analyzed the fundamental molecular mechanisms of quorum sensing in biofilms formed by anaerobic bacteria. We also highlight quorum quenching as a promising strategy to manage bacterial infections associated with anaerobic bacterial biofilms.}, }
@article {pmid39683853, year = {2024}, author = {Rogala, P and Jabłońska-Wawrzycka, A and Czerwonka, G and Hodorowicz, M and Michałkiewicz, S and Kalinowska-Tłuścik, J and Karpiel, M and Gałczyńska, K}, title = {Ruthenium Complexes with Pyridazine Carboxylic Acid: Synthesis, Characterization, and Anti-Biofilm Activity.}, journal = {Molecules (Basel, Switzerland)}, volume = {29}, number = {23}, pages = {}, pmid = {39683853}, issn = {1420-3049}, support = {Project UJK No. SUPB.RN. 24.218, SUPB.RN. 24.219, SUPB.RN. 23.256//Polish Ministry of Science and Higher Education/ ; }, mesh = {*Biofilms/drug effects ; *Ruthenium/chemistry/pharmacology ; *Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; *Carboxylic Acids/chemistry/pharmacology ; *Pyridazines/chemistry/pharmacology/chemical synthesis ; *Microbial Sensitivity Tests ; *Coordination Complexes/pharmacology/chemistry/chemical synthesis ; Pseudomonas aeruginosa/drug effects ; Molecular Structure ; }, abstract = {As a result of drug resistance, many antimicrobial medicines become ineffective, making the infections more difficult to treat. Therefore, there is a need to develop new compounds with antibacterial activity. This role may be played, for example, by metal complexes with carboxylic acids. This study reports the formation and characterization of ruthenium complexes with pyridazine-3-carboxylic acid (pdz-3-COOH)-([(η[6]-p-cym)Ru[II]Cl(pdz-3-COO)] (1), [Ru[III]Cl2(pdz-3-COO)2Na(H2O)]n(H2O)0.11 (2) and [Ru[III]Cl2(pdz-3-COO)2Na(H2O)2]n (3). The synthesized compounds were analyzed using various spectroscopic and electrochemical techniques, with structure confirmation via SC-XRD analysis. Experimental data showed the ligand binds to metal ions bidentately through the nitrogen donor of the pyridazine ring and one carboxylate oxygen. To visualize intermolecular interactions, Hirshfeld surface analysis and 2D fingerprint plots were conducted. Furthermore, the impact of ruthenium compounds (1 and 2) on the planktonic growth of selected bacterial strains and the formation of Pseudomonas aeruginosa PAO1 biofilm was examined. Both complexes demonstrated comparable anti-biofilm activity and outperformed the free ligand. The effect of the complexes on selected virulence factors of P. aeruginosa PAO1 was also investigated. Compounds 1 and 2 show high suppressive activity in pyoverdine production, indicating that the virulence of the strain has been reduced. This inhibitory effect is similar to the inhibitory effect of ciprofloxacin. Within this context, the complexes exhibit promising antibacterial activities. Importantly, the compounds showed no cytotoxic effects on normal CHO-K1 cells. Additionally, a molecular docking approach and fluorescence spectroscopy were used to determine the interactions of ruthenium complexes with human serum albumin.}, }
@article {pmid39682912, year = {2024}, author = {Peng, J and Chen, G and Guo, S and Lin, Z and Zeng, Y and Ren, J and Wang, Q and Yang, W and Liang, Y and Li, J}, title = {Anti-Bacterial and Anti-Biofilm Activities of Essential Oil from Citrus reticulata Blanco cv. Tankan Peel Against Listeria monocytogenes.}, journal = {Foods (Basel, Switzerland)}, volume = {13}, number = {23}, pages = {}, pmid = {39682912}, issn = {2304-8158}, support = {32402274//Natural Science Foundation of China/ ; 2023KTSCX051//Guangdong Universities Characteristic Innovation Project/ ; 2021A1515110660//Guangdong Basic and Applied Basic Research Foundation/ ; SL2022A04J01086//Guangzhou Basic and Applied Basic Research Foundation/ ; Heyuan2021016//Guangdong Science and Technology Special Project/ ; }, abstract = {In recent years, plant essential oils have been confirmed as natural inhibitors of foodborne pathogens. Citrus reticulata Blanco cv. Tankan peel essential oil (CPEO) showed anti-Listeria monocytogenes (LM) activities, and this study investigated the associated mechanisms by using high-resolution electron microscope, fluorescence spectrometer, flow cytometer, potentiometer, and transcriptome sequencing. The results showed that CPEO restrained LM growth at a minimum inhibitory concentration of 2% (v/v). The anti-LM abilities of CPEO were achieved by disrupting the permeability of the cell wall, damaging the permeability, fluidity, and integrity of the cell membrane, disturbing the membrane hydrophobic core, and destroying the membrane protein conformation. Moreover, CPEO could significantly inhibit the LM aggregation from forming biofilm by reducing the extracellular polymeric substances' (protein, polysaccharide, and eDNA) production and bacterial surface charge numbers. The RNA sequencing data indicated that LM genes involved in cell wall and membrane biosynthesis, DNA replication and repair, quorum sensing and two-component systems were expressed differently after CPEO treatment. These results suggested that CPEO could be used as a novel anti-LM agent and green preservative in the food sector. Further studies are needed to verify the anti-LM activities of CPEO in real food.}, }
@article {pmid39682909, year = {2024}, author = {D'Arcangelo, S and Santonocito, D and Messina, L and Greco, V and Giuffrida, A and Puglia, C and Di Giulio, M and Inturri, R and Vaccaro, S}, title = {Almond Hull Extract Valorization: From Waste to Food Recovery to Counteract Staphylococcus aureus and Escherichia coli in Formation and Mature Biofilm.}, journal = {Foods (Basel, Switzerland)}, volume = {13}, number = {23}, pages = {}, pmid = {39682909}, issn = {2304-8158}, abstract = {The increase in food waste accumulation needs innovative valorization strategies that not only reduce environmental impacts but also provide functional applications. This study investigates the potential of almond hulls, an abundant agricultural by-product, as a source of bioactive compounds. For the first time, almond hull extract (AHE), was evaluated in terms of anti-adhesive and anti-biofilm activity against Staphylococcus aureus ATCC 29213 and Escherichia coli ATCC 9637. The extract was obtained by an optimized eco-friendly green technique using ultrasound-assisted extraction (UAE), and it was characterized for its main compounds by high-performance liquid chromatography-mass spectrometry (HPLC-MS) and nuclear magnetic resonance (NMR) analysis. Antimicrobial activity was evaluated on planktonic cells by minimum inhibitory/bactericidal concentration (MIC/MBC) and by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assays. Afterward, AHE activity was evaluated against the bacterial sessile phase, both against in-formation and mature biofilm. Finally, the toxicity of the extract was tested on normal human adult cells (HDFa) by an MTT test. The principal active compounds present in AHE belong to the polyphenol group, in particular, the phenolic acid (Hydroxycinnammic sub-class) and, more significantly, the flavonoid class. The results showed that the extract has a relevant antimicrobial activity against the planktonic cells of both tested strains. Moreover, it significantly inhibited bacterial adhesion and promoted biofilm removal, highlighting its potential as a sustainable antimicrobial agent. The MTT test on human fibroblasts showed that the extract is not toxic for normal human cells. This research highlights how food waste valorization could have a high potential in the antimicrobial field.}, }
@article {pmid39682895, year = {2024}, author = {Panera-Martínez, S and Capita, R and Pedriza-González, &#xc1; and Díez-Moura, M and Riesco-Peláez, F and Alonso-Calleja, C}, title = {Occurrence, Antibiotic Resistance and Biofilm-Forming Ability of Listeria monocytogenes in Chicken Carcasses and Cuts.}, journal = {Foods (Basel, Switzerland)}, volume = {13}, number = {23}, pages = {}, pmid = {39682895}, issn = {2304-8158}, support = {RTI2018-098267-R-C33//Ministerio de Ciencia, Innovaci&#xf3;n y Universidades/ ; PID2022-142329OB-C31//Ministerio deCiencia, Innovaci&#xf3;n y Universidades/ ; LE018P20//Junta de Castilla y Le&#xf3;n (Consejer&#xed;a de Educaci&#xf3;n)/ ; }, abstract = {A total of 104 samples of chicken meat acquired on the day of slaughter from two slaughterhouses in northwestern Spain were analyzed. These comprised 26 carcasses and 26 cuts from each of the two establishments. An average load of 5.39 ± 0.61 log10 cfu/g (total aerobic counts) and 4.90 ± 0.40 log10 cfu/g (psychrotrophic microorganisms) were obtained, with differences (p < 0.05) between types of samples and between slaughterhouses. Culturing methods involving isolation based on the UNE-EN-ISO 11290-1:2018 norm and identification of isolates by polymerase chain reaction (PCR) to detect the lmo1030 gene allowed the detection of Listeria monocytogenes in 75 samples (72.1% of the total; 50.0% of the carcasses and 94.2% of the cuts). The 75 isolates, one for each positive sample, were tested for resistance against a panel of 15 antibiotics of clinical interest by the disc diffusion method. All isolates belonged to the serogroup IIa (multiplex PCR assay) and showed resistance to between four and ten antibiotics, with an average value of 5.7 ± 2.0 resistances per isolate, this rising to 7.0 ± 2.1 when strains with resistance and reduced susceptibility were taken together. A high prevalence of resistance was observed for antibiotics belonging to the cephalosporin and quinolone families. However, the level of resistance was low for antibiotics commonly used to treat listeriosis (e.g., ampicillin or gentamicin). Nine different resistance patterns were noted. One isolate with each resistance pattern was tested for its ability to form biofilms on polystyrene during 72 h at 12 °C. The total biovolume of the biofilms registered through confocal laser scanning microscopy (CLSM) in the observation field of 16,078.24 μm[2] ranged between 13,967.7 ± 9065.0 μm[3] and 33,478.0 ± 23,874.1 μm[3], and the biovolume of inactivated bacteria between 0.5 ± 0.4 μm[3] and 179.1 ± 327.6 μm[3]. A direct relationship between the level of resistance to antibiotics and the ability of L. monocytogenes strains to form biofilms is suggested.}, }
@article {pmid39681855, year = {2024}, author = {Chen, T and Zhou, X and Feng, R and Shi, S and Chen, X and Wei, B and Hu, Z and Peng, T}, title = {Author Correction: Novel function of single-target regulator NorR involved in swarming motility and biofilm formation revealed in Vibrio alginolyticus.}, journal = {BMC biology}, volume = {22}, number = {1}, pages = {285}, pmid = {39681855}, issn = {1741-7007}, }
@article {pmid39680756, year = {2024}, author = {Syed, AK and Baral, R and Van Vlack, ER and Gil-Marqués, ML and Lenhart, T and Hooper, DC and Kahne, D and Losick, R and Bradshaw, N}, title = {Biofilm formation by Staphylococcus aureus is triggered by a drop in the levels of a cyclic dinucleotide.}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, volume = {121}, number = {52}, pages = {e2417323121}, pmid = {39680756}, issn = {1091-6490}, support = {R01 AI139011/AI/NIAID NIH HHS/United States ; startup funds//Brandeis University (BU)/ ; fellowship//Real Colegio Complutense Fellowship/ ; R01 AI057576/AI/NIAID NIH HHS/United States ; P01 AI083214/AI/NIAID NIH HHS/United States ; 5R01 AI139011//HHS | National Institutes of Health (NIH)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Staphylococcus aureus/genetics/physiology/metabolism ; *Bacterial Proteins/metabolism/genetics ; Animals ; Mice ; Dinucleoside Phosphates/metabolism ; Gene Expression Regulation, Bacterial ; Phosphoric Diester Hydrolases/metabolism/genetics ; Staphylococcal Infections/microbiology ; Glucose/metabolism ; Second Messenger Systems ; }, abstract = {The bacterial pathogen Staphylococcus aureus forms multicellular communities known as biofilms in which cells are held together by an extracellular matrix principally composed of repurposed cytoplasmic proteins and extracellular DNA. These biofilms assemble during infections or under laboratory conditions by growth on medium containing glucose, but the intracellular signal for biofilm formation and its downstream targets were unknown. Here, we present evidence that biofilm formation is triggered by a drop in the levels of the second messenger cyclic-di-AMP. Previous work identified genes needed for the release of extracellular DNA, including genes for the cyclic-di-AMP phosphodiesterase GdpP, the transcriptional regulator XdrA, and the purine salvage enzyme Apt. Using a cyclic-di-AMP riboswitch biosensor and mass spectrometry, we show that the second messenger drops in abundance during biofilm formation in a glucose-dependent manner. Mutation of these three genes elevates cyclic-di-AMP and prevents biofilm formation in a murine catheter model. Supporting the generality of this mechanism, we found that gdpP was required for biofilm formation by diverse strains of S. aureus. We additionally show that the downstream consequence of the drop in cyclic-di-AMP is inhibition of the "accessory gene regulator" operon agr, which is known to suppress biofilm formation through phosphorylation of the transcriptional regulator AgrA by the histidine kinase AgrC. Consistent with this, an agr mutation bypasses the block in biofilm formation and eDNA release caused by a gdpP mutation. Finally, we report the unexpected observation that GdpP inhibits phosphotransfer from AgrC to AgrA, revealing a direct connection between the phosphodiesterase and agr.}, }
@article {pmid39680392, year = {2024}, author = {Kishimoto, T and Fukuda, K and Ishida, W and Kuwana, A and Todokoro, D and Uchiyama, J and Matsuzaki, S and Yamashiro, K}, title = {Disruption of the Enterococcus faecalis-Induced Biofilm on the Intraocular Lens Using Bacteriophages.}, journal = {Translational vision science &amp; technology}, volume = {13}, number = {12}, pages = {25}, pmid = {39680392}, issn = {2164-2591}, mesh = {*Biofilms/growth &amp; development/drug effects ; *Enterococcus faecalis/virology/physiology ; *Lenses, Intraocular/microbiology ; *Bacteriophages/genetics/physiology ; *Vancomycin/pharmacology ; Humans ; Anti-Bacterial Agents/pharmacology ; Microscopy, Electron, Scanning ; Gram-Positive Bacterial Infections/microbiology ; }, abstract = {PURPOSE: To compare the effects of bacteriophages (phages) and vancomycin on Enterococcus faecalis-induced biofilms on the intraocular lens.<br><br>METHODS: E. faecalis strains EF24, GU02, GU03, and phiEF14H1 were used. The expression of the enterococcus surface protein (esp) gene was analyzed using polymerase chain reaction. Phages or vancomycin was added to the biofilms formed on culture plates or acrylic intraocular lenses. The biofilms were quantified after staining with crystal violet. The structure of the biofilms was analyzed using scanning electron microscopy.<br><br>RESULTS: E. faecalis strains EF24, GU02, and GU03 formed biofilms on cell culture plates; however, the esp-negative GU03 strain had a significantly lower biofilm-forming ability than the esp-positive strains EF24 and GU02. The addition of phiEF14H1 resulted in a significant reduction in biofilm mass produced by both EF24 and GU02 compared with the untreated control. However, the addition of vancomycin did not degrade the biofilms. Phages significantly degraded biofilms and reduced the viable EF24 and GU02 bacteria on the intraocular lens.<br><br>CONCLUSIONS: Phages can degrade biofilms formed on the intraocular lens and destroy the bacteria within it. Thus, phage therapy may be a new treatment option for refractory and recurrent endophthalmitis caused by biofilm-forming bacteria.<br><br>TRANSLATIONAL RELEVANCE: Phage therapy, a novel treatment option for refractory and recurrent endophthalmitis caused by biofilm-forming bacteria, effectively lyses E.&#xa0;faecalis-induced biofilms.}, }
@article {pmid39678983, year = {2024}, author = {Sharma, A and Kumar, Y and Kumar, G and Tahlan, AK}, title = {Biofilm Production and Antibiogram Profiles in Escherichia coli and Salmonella.}, journal = {Indian journal of microbiology}, volume = {64}, number = {4}, pages = {1512-1517}, pmid = {39678983}, issn = {0046-8991}, abstract = {Salmonella and Escherichia coli are important enteric pathogens associated with a variety of infections. Biofilm formation and antimicrobial resistance are important characteristics making these pathogens a concern in terms of strong attachment to substrates, expression of virulence markers and difficult removal. The present study investigates the biofilm-forming ability and antibiogram patterns among E. coli and Salmonella spp. A total of 200 E. coli and 100 Salmonella isolates received at National Salmonella and Escherichia Centre were identified by biochemical testing, followed by serotyping. Biofilm production was detected by Tissue Culture Plate method. The isolates were further subjected to Antibiotic Susceptibility Testing by the Kirby-Bauer disk diffusion method. 113 (56.5%) E. coli isolates and 79 (79%) Salmonella isolates were detected as biofilm producers. A total of 114(57%)E. coli isolates and 31(31%) Salmonella isolates were found to be resistant to multiple drugs when Antibiotic Susceptibility Testing was carried out. Antibiotic resistance was found to be significantly higher in biofilm producing salmonella (p = 0.001) whereas in the case of E. coli the difference remained non-significant (p = 0.4454). The capability to produce biofilm along with acquiring high level of antimicrobial resistance in salmonella and E. coli provide enhanced survival potential in adverse environments. Therefore, it becomes a serious cause of concern for public health authorities considering the virulence of these bacteria and their association with different disease conditions and requires urgent intervention with regards to control and prevention strategies.}, }
@article {pmid39678958, year = {2024}, author = {Jin, HW and Eom, YB}, title = {Antibacterial and Anti-biofilm Effects of Thymoquinone Against Carbapenem-Resistant Uropathogenic Escherichia coli.}, journal = {Indian journal of microbiology}, volume = {64}, number = {4}, pages = {1747-1756}, pmid = {39678958}, issn = {0046-8991}, abstract = {Carbapenem antibiotics are widely used for their broad antibacterial effects, but the emergence of carbapenem-resistant Enterobacterales has recently become a global problem. To solve this problem, research is needed to find compounds that increase antibiotic activity. Therefore, this study aimed to validate the antibacterial and anti-biofilm effects, as well as the inhibition of gene expression of thymoquinone, an extract of Nigella sativa commonly used as a spice in many dishes. The minimum inhibitory concentration of carbapenem antibiotics and thymoquinone was determined. Phenotypic analysis was performed to confirm the effect of thymoquinone on motility, which is one of the virulence factors of carbapenem-resistant uropathogenic Escherichia coli (CR-UPEC). Furthermore, quantitative real-time polymerase chain reaction analysis was used to determine the expression levels of carbapenemase gene (bla KPC), efflux pump genes (acrA, acrB, acrD, tolC), as well as motility and adhesion genes (fliC, motA). In addition, biofilm inhibition and biofilm eradication assays were performed. All strains showed resistance to carbapenem antibiotics, while an antibacterial effect was confirmed at a concentration of 256 μg/mL of thymoquinone. Phenotypic analysis revealed a nearly 50% suppression in migration distance compared to the control group at 128 μg/mL of thymoquinone. Subsequent gene expression tests indicated the downregulation of carbapenemase-, efflux pump-, motility-, and adhesion genes by thymoquinone. Furthermore, our findings demonstrated that thymoquinone exhibits both biofilm formation inhibition and eradication effects. These findings suggest that thymoquinone may serve as a potential antibiotic adjuvant for treating CR-UPEC and could be a valuable resource in combating UTIs caused by multidrug-resistant bacteria.}, }
@article {pmid39678029, year = {2024}, author = {Ye, Z and van der Wildt, B and Nurmohamed, FRHA and van Duyvenbode, JFFH and van Strijp, J and Vogely, HC and Lam, MGEH and Dadachova, E and Weinans, H and van der Wal, BCH and Poot, AJ}, title = {Radioimmunotherapy combating biofilm-associated infection in vitro.}, journal = {Frontiers in medicine}, volume = {11}, number = {}, pages = {1478636}, pmid = {39678029}, issn = {2296-858X}, abstract = {BACKGROUND: Addressing prosthetic joint infections poses a significant challenge within orthopedic surgery, marked by elevated morbidity and mortality rates. The presence of biofilms and infections attributed to Staphylococcus aureus (S. aureus) further complicates the scenario.<br><br>OBJECTIVE: To investigate the potential of radioimmunotherapy as an innovative intervention to tackle biofilm-associated infections.<br><br>METHODS: Our methodology involved employing specific monoclonal antibodies 4497-IgG1, designed for targeting wall teichoic acids found on S. aureus and its biofilm. These antibodies were linked with radionuclides actinium-225 ([225]Ac) and lutetium-177 ([177]Lu) using DOTA as a chelator. Following this, we evaluated the susceptibility of S. aureus and its biofilm to radioimmunotherapy in vitro, assessing bacterial viability and metabolic activity via colony-forming unit enumeration and xylenol tetrazolium assays.<br><br>RESULTS: Both [[225]Ac]4497-IgG1 and [[177]Lu]4497-IgG1 exhibited a noteworthy dose-dependent reduction in S. aureus in planktonic cultures and biofilms over a 96-h exposure period, compared to non-specific antibody control groups. Specifically, doses of 7.4 kBq and 7.4 MBq of [[225]Ac]4497-IgG1 and [[177]Lu]4497-IgG1 resulted in a four-log reduction in planktonic bacterial counts. Within biofilms, 14.8 kBq of [[225]Ac]4497-IgG1 and 14.8 Mbq [[177]Lu]4497-IgG1 led to reductions of two and four logs, respectively.<br><br>CONCLUSION: Our findings underscore the effectiveness of [[225]Ac]4497-IgG1 and [[177]Lu]4497-IgG1 antibodies in exerting dose-dependent bactericidal effects against planktonic S. aureus and biofilms in vitro. This suggests that radioimmunotherapy might serve as a promising targeted treatment approach for combating S. aureus and its biofilm.}, }
@article {pmid39677627, year = {2024}, author = {Bhattacharya, M and Scherr, TD and Lister, J and Kielian, T and Horswill, AR}, title = {Matrix porosity is associated with Staphylococcus aureus biofilm survival during prosthetic joint infection.}, journal = {bioRxiv : the preprint server for biology}, volume = {}, number = {}, pages = {}, pmid = {39677627}, issn = {2692-8205}, support = {I01 BX002711/BX/BLRD VA/United States ; P01 AI083211/AI/NIAID NIH HHS/United States ; }, abstract = {Biofilms are a cause of chronic, non-healing infections. Staphylococcus aureus is a proficient biofilm forming pathogen commonly isolated from prosthetic joint infections that develop following primary arthroplasty. Extracellular adhesion protein (Eap), previously characterized in planktonic or non-biofilm populations as being an adhesin and immune evasion factor, was recently identified in the exoproteome of S. aureus biofilms. This work demonstrates that Eap and its two functionally orphaned homologs EapH1 and EapH2, contribute to biofilm structure and prevent macrophage invasion and phagocytosis into these communities. Biofilms unable to express Eap proteins demonstrated increased porosity and reduced biomass. We describe a role for Eap proteins in vivo using a mouse model of S. aureus prosthetic joint infection. Results suggest that the protection conferred to biofilms by Eap proteins is a function of biofilm structural stability that interferes with the leukocyte response to biofilm-associated bacteria.}, }
@article {pmid39677066, year = {2024}, author = {Gebremariam, T and Eguale, T and Belay, T and Kalayu, AA and Abula, T and Engidawork, E}, title = {Antibiotic Resistance, and Biofilm Forming Characteristics of Escherichia coli Clinical Isolates at a Hospital in Tigray, Northern Ethiopia.}, journal = {Cureus}, volume = {16}, number = {11}, pages = {e73569}, pmid = {39677066}, issn = {2168-8184}, abstract = {BACKGROUND: Escherichia coli (E. coli) infections are becoming difficult to treat due to the bacterium's biofilm-forming capabilities and rising resistance to multiple antibiotics, posing a growing clinical challenge. This study assessed the antimicrobial resistance and biofilm formation by Escherichia coli isolates from patients at a hospital in Tigray, Northern Ethiopia.<br><br>METHOD: From patients exhibiting signs of bacterial infection, while excluding recent antibiotic users or those with incomplete data, 417 clinical samples comprised of 84 blood, 108 pus, and 225 urine samples were obtained in a cross-sectional study. The combination disc method was used to test extended-spectrum beta-lactamase (ESBL) production, and Ampicillin C (AmpC) enzyme presence was confirmed with cefoxitin and cefotaxime discs. Data analysis was conducted with SPSS version 22 software, applying ANOVA and logistic regression, with significance set at p<0.05.<br><br>RESULT: Among the 417 samples, 109 (26.1%) tested positive for Escherichia coli. These isolates showed high resistance to ampicillin (84.4%) but lower resistance to meropenem (9.17%). ESBL was detected in 46.8% of isolates and AmpC in 54%, with 48 (44%) isolates positive for both. Strong biofilm formation occurred in 76% of isolates, while only 2.75% were weak producers. Biofilm strength correlated significantly with prior antibiotic use (p=0.028), ward type (p=0.001), and use of indwelling devices (p=0.000).<br><br>CONCLUSION: In northern Ethiopia, Escherichia coli isolates showed resistance to major antibiotic classes like beta-lactams, fluoroquinolones, and aminoglycosides. This high resistance and biofilm development highlight the critical need for interventions to curb resistance spread, with a focus on antibiofilm research and enhanced infection prevention measures.}, }
@article {pmid39676255, year = {2024}, author = {Shankar Das, B and Sarangi, A and Pahuja, I and Singh, V and Ojha, S and Giri, S and Bhaskar, A and Bhattacharya, D}, title = {Thymol as Biofilm and Efflux Pump Inhibitor: A Dual-Action Approach to Combat Mycobacterium tuberculosis.}, journal = {Cell biochemistry and function}, volume = {42}, number = {8}, pages = {e70030}, doi = {10.1002/cbf.70030}, pmid = {39676255}, issn = {1099-0844}, support = {//This work was supported by the grant provided from DST-SERB, Government of India (SRG/2020/001922) and UGC, Government of India (UGC FD Diary No. 2183, 01-06-2022 &amp; No. F.30-523/2020(BSR). Part of the work was also supported by initial funding provided to DB in IISER, Bhopal./ ; }, mesh = {*Biofilms/drug effects ; *Thymol/pharmacology/chemistry ; *Mycobacterium tuberculosis/drug effects/metabolism ; *Microbial Sensitivity Tests ; *Antitubercular Agents/pharmacology/chemistry ; Mycobacterium smegmatis/drug effects/metabolism ; Molecular Docking Simulation ; Bacterial Proteins/metabolism/antagonists &amp; inhibitors ; Rifampin/pharmacology ; Reactive Oxygen Species/metabolism ; Isoniazid/pharmacology ; Membrane Transport Proteins/metabolism ; }, abstract = {Tuberculosis (TB) remains a significant global health challenge, exacerbated by the emergence of drug-resistant strains of Mycobacterium tuberculosis (M. tb). The complex biology of M. tb, particularly its key porins, contributes to its resilience against conventional treatments, highlighting the exploration of innovative therapeutic strategies. Following with this challenges, the present study investigates the bioactivity properties of phenolic compounds derived from the terpene groups, specifically through Thymol (THY) against M. smegmatis as a surrogated model for M. tb. Furthermore, the study employed with combination of two approaches i.e., in vitro assays and computational methods to evaluate the efficacy of THY against M. smegmatis and its interaction with M. tb biofilm and efflux pump proteins, particularly Rv1258c and Rv0194. The in vitro findings demonstrated that THY exhibits inhibitory activity against M. smegmatis and shows promising interaction with a combination of isoniazid (INH) and rifampicin (RIF) of TB regimens. Furthermore, THY demonstrated significant inhibitory action towards motility and biofilm formation of M. smegmatis. The combination of THY with INH and RIF exhibited a synergistic effect, enhancing the overall antimicrobial efficacy. Additionally, THY displayed reactive oxygen species (ROS) activity and potential efflux pump inhibitory action towards M. smegmatis. The computational analysis revealed that THY interacts effectively with efflux pump proteins Rv1258c and Rv0194, showing superior binding affinity compared to verapamil, a known efflux pump inhibitor. Pharmacokinetic studies highlighted that THY possess a favourable safety profile. In conclusion, THY represents a promising inhibitory compound for tuberculosis prevention, potentially addressing challenges posed by drug resistance.}, }
@article {pmid39675511, year = {2024}, author = {Wang, Y and Liu, Y and Chen, J and Ge, Z and Wang, J and Li, D}, title = {D-arginine-loaded pH-responsive mesoporous silica nanoparticles enhances the efficacy of water jet therapy in decontaminating biofilm-coated titanium surface.}, journal = {Journal of controlled release : official journal of the Controlled Release Society}, volume = {378}, number = {}, pages = {390-401}, doi = {10.1016/j.jconrel.2024.12.020}, pmid = {39675511}, issn = {1873-4995}, abstract = {Peri-implantitis, caused by bacterial biofilm on dental implants, leads to bone loss and tissue inflammation, ultimately causing oral health decline. Traditional methods to remove biofilm are ineffective in promoting reosseointegration on implant surfaces. This phenomenon can be attributed to two factors: incomplete removal of biofilm from hard-to-reach areas and alterations in the physicochemical properties of implant surfaces caused by decontamination procedures. To address this problem, we developed D-arginine-loaded chitooligosaccharide-capped pH-responsive mesoporous silica nanoparticles (Dar@MSN-COS) for improving the efficacy of decontamination of Water Jet (WJ). Dar@MSN-COS particles exhibit a targeted approach towards the extracellular polymeric substance (EPS) in order to disrupt the biofilm, and possess the capability to infiltrate confined areas between implant screws. Following this, the WJ treatment effectively removed residual biofilm and demonstrated improved cleaning efficacy. Furthermore, the decontamination of the Dar@MSN-COS combination with WJ promotes effective cell cytocompatibility on the titanium surface. The results of mechanistic experiments indicate that Dar@MSN-COS may act on biofilms by releasing a significant quantity of reactive oxygen species (ROS), suggesting it as a key contributing factor. In summary, our novel therapeutic protocol shows promise as an alternative solution for addressing the clinically complex aspects of peri-implantitis.}, }
@article {pmid39675440, year = {2025}, author = {Musinguzi, B and Akampurira, A and Derick, H and Turyamuhika, L and Mwesigwa, A and Mwebesa, E and Mwesigye, V and Kabajulizi, I and Sekulima, T and Ocheng, F and Itabangi, H and Mboowa, G and Sande, OJ and Achan, B}, title = {Extracellular hydrolytic enzyme activities and biofilm formation in Candida species isolated from people living with human immunodeficiency virus with oropharyngeal candidiasis at HIV/AIDS clinics in Uganda.}, journal = {Microbial pathogenesis}, volume = {199}, number = {}, pages = {107232}, pmid = {39675440}, issn = {1096-1208}, support = {D43 TW010132/TW/FIC NIH HHS/United States ; }, mesh = {*Biofilms/growth &amp; development ; Humans ; *Candidiasis, Oral/microbiology ; *Candida/enzymology/isolation &amp; purification/pathogenicity ; Uganda ; *HIV Infections/complications/microbiology ; Phospholipases/metabolism ; Esterases/metabolism ; Peptide Hydrolases/metabolism ; Hemolysin Proteins/metabolism ; Oropharynx/microbiology ; AIDS-Related Opportunistic Infections/microbiology ; }, abstract = {BACKGROUND: Commensal oral Candida species can become opportunistic and transition to pathogenic causes of oropharyngeal candidiasis (OPC) in individuals with impaired immunity through ecological cues and the expression of extracellular hydrolytic enzyme activities and biofilm formation.<br><br>OBJECTIVE: We evaluated phospholipase, proteinase, hemolysin, esterase, and coagulase enzymatic activities and biofilm formation in Candida species isolated from people living with human immunodeficiency virus (PLHIV) with OPC.<br><br>METHODS: Thirty-five Candida isolates from PLHIV with OPC were retrieved from a sample repository and evaluated for phospholipase activity using the egg yolk agar method, proteinase activity using the bovine serum albumin agar method, hemolysin activity using the blood agar plate method, esterase activity using the Tween 80 opacity test medium method, coagulase activity using the classical tube method, and biofilm formation using the microtiter plate assay method in vitro.<br><br>RESULTS: A total of 35 Candida isolates obtained from PLHIV with OPC were included in this study, and phospholipase and proteinase activities were detected in 33/35 (94.3&#xa0;%) and 31/35 (88.6&#xa0;%) Candida isolates, respectively. Up to 25/35 (71.4&#xa0;%) of the Candida isolates exhibited biofilm formation, whereas esterase activity was demonstrated in 23/35 (65.7&#xa0;%) of the Candida isolates. Fewer isolates (21/35, 60&#xa0;%) produced hemolysin, and coagulase production was the least common virulence activity detected in 18/35 (51.4&#xa0;%) of the Candida isolates.<br><br>CONCLUSION: Phospholipase and proteinase activities were the strongest in oropharyngeal Candida species.}, }
@article {pmid39674811, year = {2024}, author = {Machida-Sano, I and Koizumi, H and Yoshitake, S}, title = {A novel scaffold for biofilm formation by soil microbes using iron-cross-linked alginate gels.}, journal = {Bioscience, biotechnology, and biochemistry}, volume = {}, number = {}, pages = {}, doi = {10.1093/bbb/zbae197}, pmid = {39674811}, issn = {1347-6947}, abstract = {This study aimed to evaluate the suitability of alginate gels, specifically ferric-ion-cross-linked alginate (Fe-alginate) and calcium-ion-cross-linked alginate (Ca-alginate), as scaffolds for soil microbial attachment and biofilm formation in soil. Staining with crystal violet and observations with scanning electron microscopy showed that microorganisms formed biofilms on Fe-alginate surfaces in the soil. When the soil was incubated with Fe-alginate, microbial biomass, estimated by adenosine triphosphate content, increased not only in the Fe-alginate but also in the surrounding soil. The weight of Ca-alginate in the soil decreased with time owing to chemical dissolution. However, the weight of Fe-alginate in the soil did not decrease, likely because it was protected by the microbial biofilm that formed on its surface. These results demonstrate that the use of Fe-alginate, in contrast to Ca-alginate, as a scaffold may allow for more efficient use of soil microbial functions in agriculture and bioremediation.}, }
@article {pmid39674248, year = {2025}, author = {Fan, F and Li, M and Dou, J and Zhang, J and Li, D and Meng, F and Dong, Y}, title = {Functional characteristics and mechanisms of microbial community succession and assembly in a long-term moving bed biofilm reactor treating real municipal wastewater.}, journal = {Environmental research}, volume = {267}, number = {}, pages = {120602}, doi = {10.1016/j.envres.2024.120602}, pmid = {39674248}, issn = {1096-0953}, mesh = {*Bioreactors/microbiology ; *Biofilms/growth &amp; development ; *Wastewater/microbiology ; *Waste Disposal, Fluid/methods ; Microbiota ; Bacteria/metabolism/genetics ; Biological Oxygen Demand Analysis ; }, abstract = {Moving bed biofilm reactor (MBBR) technology with diverse merits is efficient in treating various waste streams whereas their microbial functional properties and ecology still need in-depth investigation, especially in real wastewater treatment systems. Herein, a well-controlled MBBR treating municipal wastewater was established to investigate the long-term system performance and the underlying principles of community succession and assembly. The system successfully achieved ammonium, TN, and chemical oxygen demand (COD) removal of 96.7 ± 2.2%, 75.2 ± 3.6%, and 90.3 ± 3.8%, respectively, under simplified operation and low energy consumption. The effluent TN concentrations achieved 6.2 ± 1.6 mg-N/L despite the influent fluctuations. Diverse functional denitrifiers, such as Denitratisoma, Thermomonas, and Flavobacterium, and the anammox bacteria Candidatus Brocadia successfully enriched in anoxic chamber biofilms. The nitrifiers Nitrosomonas (∼0.73%) and Nitrospira (∼14.0%) exhibited appreciable nitrification capacity in specialized aerobic chambers. Ecological null model and network analysis revealed that microbial community assembly was mainly regulated by niche-based deterministic processes and air diffusion in the aerobic chamber resulted in more intense and complex bacterial interactions. Environmental filters including influent substrate and operating conditions (e.g., reactor configuration, DO, and temperature) greatly shaped the microbial community structure and affected carbon and nitrogen metabolism. The positive ecological roles of influent microflora and functional redundancy in biofilm communities were believed to facilitate functional stability. The anammox process coupled with partial denitrification in a specialized chamber demonstrated positive application implications. These findings provided valuable perspectives in deciphering the microbiological and ecological mechanisms, functional properties, and application potentials of MBBR.}, }
@article {pmid39674004, year = {2025}, author = {Zhang, J and Yang, P and Zeng, Q and Zhang, Y and Zhao, Y and Wang, L and Li, Y and Wang, Z and Wang, Q}, title = {Arginine kinase McsB and ClpC complex impairs the transition to biofilm formation in Bacillus subtilis.}, journal = {Microbiological research}, volume = {292}, number = {}, pages = {127979}, doi = {10.1016/j.micres.2024.127979}, pmid = {39674004}, issn = {1618-0623}, mesh = {*Biofilms/growth &amp; development ; *Bacillus subtilis/genetics/physiology ; *Bacterial Proteins/genetics/metabolism ; *Gene Expression Regulation, Bacterial ; Transcription Factors/metabolism/genetics ; Polysaccharides, Bacterial/metabolism ; Repressor Proteins/genetics/metabolism ; Heat-Shock Proteins ; Protein Kinases ; }, abstract = {Robust biofilm formation on host niches facilitates beneficial Bacillus to promote plant growth and inhibit plant pathogens. Arginine kinase McsB is involved in bacterial development and stress reaction by phosphorylating proteins for degradation through a ClpC/ClpP protease. Conversely, cognate arginine phosphatase YwlE counteracts the process. Regulatory pathways of biofilm formation have been studied in Bacillus subtilis, of which Spo0A∼P is a master transcriptional regulator, which is transcriptionally activated by itself in biofilm formation. Previous studies have shown that Spo0A∼P transcript regulation controls biofilm formation, where MecA binds ClpC to inhibit Spo0A∼P-dependent transcription without triggering degradation. It remains unclear whether McsB and ClpC regulate biofilm formation together and share a similar non-proteolytic mechanism like MecA/ClpC complex. In this study, we characterized McsB and ClpC as negative regulators of biofilm formation and matrix gene eps expression. Our genetic and morphological evidence further indicates that McsB and ClpC inhibit eps expression by decreasing the spo0A and sinI expression, leading to the release of SinR, a known repressor of eps transcription. Given that the spo0A and sinI expression is transcriptionally activated by Spo0A∼P in biofilm formation, we next demonstrate that McsB interacts with Spo0A directly by bacterial two-hybrid system and Glutathione transferase pull-down experiments. Additionally, we present that McsB forms a complex with ClpC to dampen biofilm formation in vivo. Finally, we show that YwlE acts as a positive regulator of biofilm formation, counteracting the function of McsB. These findings suggest that McsB, ClpC, and YwlE play vital roles in the transition to biofilm formation in Bacillus subtilis, providing new insights into the regulatory mechanisms underlying biofilm development and sharing a similar non-proteolytic mechanism in biofilm formation as MecA/ClpC complex.}, }
@article {pmid39656705, year = {2024}, author = {Yu, Y and Kim, YH and Cho, WH and Son, BS and Yeo, HJ}, title = {Correction: Biofilm microbiome in extracorporeal membrane oxygenator catheters.}, journal = {PloS one}, volume = {19}, number = {12}, pages = {e0315755}, pmid = {39656705}, issn = {1932-6203}, abstract = {[This corrects the article DOI: 10.1371/journal.pone.0257449.].}, }
@article {pmid39673313, year = {2024}, author = {Watkins, JD and Lords, CJ and Bradley, AM and Cutler, DR and Sims, RC}, title = {Factorial experiment to identify two-way interactions between temperature, harvesting period, hydraulic retention time, and light intensity that influence the biomass productivity and phosphorus removal efficiency of a microalgae-bacteria biofilm.}, journal = {Water science and technology : a journal of the International Association on Water Pollution Research}, volume = {90}, number = {11}, pages = {2961-2977}, pmid = {39673313}, issn = {0273-1223}, support = {DE-EE0009271//Bioenergy Technologies Office/ ; }, mesh = {*Microalgae/growth &amp; development/metabolism ; *Biomass ; *Phosphorus/metabolism ; *Biofilms/growth &amp; development ; *Temperature ; *Bioreactors ; Light ; Waste Disposal, Fluid/methods ; Time Factors ; Bacteria/metabolism ; }, abstract = {Rotating algae biofilm reactors (RABRs) can reduce energy requirements for wastewater reclamation but require further optimization for implementation at water resource recovery facilities (WRRF). Optimizing RABR operation is challenging because conditions at WRRF change frequently, and disregarding interaction terms related to these changes can produce incorrect conclusions about RABR behavior. This study evaluated the two-way interaction and main effects of four factors on the biomass productivity and phosphorus removal efficiency of a microalgae-bacteria biofilm grown in municipal anaerobic digester centrate, with factor levels and operating conditions selected to mimic a pilot RABR at a WRRF in Utah. Two-way interactions harvesting period*light intensity (LI), harvesting period*temperature, and LI*hydraulic retention time (HRT) had significant effects on biomass productivity: at high temperature and low LI, highest biomass productivity was achieved with a 14-day harvesting period, but at medium temperature and high LI, highest biomass productivity was achieved with a 7-day harvesting period. At high HRT, highest biomass productivity occurred at low LI, but at low HRT, highest biomass productivity occurred at high LI. Phosphorus removal was strongly influenced by LI and occurred most rapidly during the first 2 days HRT, which suggests precipitation contributed significantly to phosphorus removal. These observations provide insight for further RABR optimization.}, }
@article {pmid39672057, year = {2024}, author = {Araujo, TT and Debortolli, ALB and Carvalho, TS and Rodrigues, CMVBF and Dionizio, A and de Souza, BM and Vertuan, M and Ventura, TM and Grizzo, LT and Marchetto, R and Henrique Silva, F and Chiaratti, M and Santos, AC and Alves, LO and Ferro, M and Buzalaf, MAR}, title = {Paving the way for the use of Statherin-Derived Peptide (StN15) to control caries through acquired pellicle and biofilm microbiome engineering: Proof-of-concept in vitro/in vivo studies.}, journal = {Archives of oral biology}, volume = {171}, number = {}, pages = {106159}, doi = {10.1016/j.archoralbio.2024.106159}, pmid = {39672057}, issn = {1879-1506}, abstract = {OBJECTIVE: This proof-of-concept sequence of in vivo/in vitro studies aimed to unveil the role of acquired enamel pellicle (AEP) engineering with statherin-derived peptide (StN15) on the AEP protein profile, enamel biofilm microbiome in vivo and on enamel demineralization in vitro.<br><br>DESIGN: In vivo studies, 10 volunteers, in 2 independent experiments (2 days each), rinsed (10&#x202f;mL,1&#x202f;min) with: deionized water (negative control) or 1.88&#x202f;&#xd7;&#x202f;10[-5] M StN15. The AEP, formed along 2&#x202f;h and the biofilm, along 3&#x202f;h, were collected. AEP was analyzed by quantitative shotgun-label-free proteomics. The enamel biofilm microbiome was evaluated using 16S-rRNA Next Generation Sequencing (NGS). An in vitro model with microcosm biofilm was employed. Bovine enamel samples (n&#x202f;=&#x202f;72) were treated with 1) Phosphate-Buffer-Solution (PBS), 2) 0.12&#x202f;%Chlorhexidine, 3) 500ppmNaF; 4) 1.88&#x202f;&#xd7;&#x202f;10[-5]MStN15; 5) 3.76&#x202f;&#xd7;&#x202f;10[-5]MStN15 and 6) 7.52&#x202f;&#xd7;&#x202f;10[-5]MStN15. Biofilm was supplemented with human saliva and McBain saliva and cultivated for 5 days. Resazurin, colony forming units (CFU) and Transversal Microradiography Analysis-(TMR) were performed.<br><br>RESULTS: Proteomic results showed several proteins with acid-resistant, calcium-binding, and antimicrobial properties in the StN15 group. The microbiome corroborated these findings, reducing bacteria that are closely related to dental caries in the StN15 group, compared to the PBS. The microcosm biofilm showed that the lowest concentration of StN15 was the most efficient in reducing bacterial activity, CFU and enamel demineralization compared to PBS.<br><br>CONCLUSION: StN15 can effectively alter the AEP proteome to inhibit initial bacterial colonization, thereby mitigating enamel demineralization. Future research should explore clinical applications and elucidate the mechanisms underlying the protective effects of StN15.}, }
@article {pmid39671748, year = {2025}, author = {Mathivanan, K and Zhang, R and Chandirika, JU and Mathimani, T and Wang, C and Duan, J}, title = {Bacterial biofilm-based bioleaching: Sustainable mitigation and potential management of e-waste pollution.}, journal = {Waste management (New York, N.Y.)}, volume = {193}, number = {}, pages = {221-236}, doi = {10.1016/j.wasman.2024.12.010}, pmid = {39671748}, issn = {1879-2456}, mesh = {*Biofilms ; *Electronic Waste ; Recycling/methods ; Bacteria/metabolism ; Waste Management/methods ; Metals/metabolism ; }, abstract = {Significant advances in the electrical and electronic industries have increased the use of electrical and electronic equipment and its environmental emissions. The e-waste landfill disposal has deleterious consequences on human health and environmental sustainability, either directly or indirectly. E-waste containing ferrous and non-ferrous materials can harm the surrounding aquatic and terrestrial environments. Therefore, recycling e-waste and recovering metals from it before landfill disposal is an important part of environmental management. Although various chemical and physical processes are being used predominantly to recover metals from e-waste, the bioleaching process has gained popularity in recent years due to its eco-friendliness and cost-effectiveness. Direct contact between microbes and e-waste is crucial for continuous metal dissolution in the bio-leaching process. Biofilm formation is key for the continuous dissolution of metals from e-waste in contact bioleaching. Critical reviews on microbial activities and their interaction mechanisms on e-waste during metal bioleaching are scarce. Therefore, this review aims to explore the advantages and disadvantages of biofilm formation in contact bioleaching and the practical challenges in regulating them. In this review, sources of e-waste, available metallurgical methods, bioleaching process, and types of bioleaching microbes are summarized. In addition, the significance of biofilm formation in contact bioleaching and the role and correlation between EPS production, cyanide production, and quorum sensing in the biofilm are discussed for continuous metal dissolution. The review reveals that regulation of quorum sensing by exogenous and endogenous processes facilitates biofilm formation, leading to continuous metal dissolution in contact bioleaching.}, }
@article {pmid39670561, year = {2024}, author = {Gunasekaran, G and Madhubala, MM and Nayanthara, GS and Mahalaxmi, S}, title = {Photodynamic antibacterial evaluation of polydopamine nanoparticle optimised Curcumin Longa against endodontic biofilm-An in-vitro study.}, journal = {Australian endodontic journal : the journal of the Australian Society of Endodontology Inc}, volume = {}, number = {}, pages = {}, doi = {10.1111/aej.12910}, pmid = {39670561}, issn = {1747-4477}, support = {//Indian Endodontic Society/ ; }, abstract = {This study aims to evaluate the effect of antimicrobial photodynamic therapy(aPDT) with polydopamine nanoparticle functionalised with Curcuma longa(nPD-Cur) against root canal biofilm. nPD-Cur was prepared and characterised using Scanning Electron Microscopy(SEM), dynamic light scattering(DLS), Fourier-transform infrared spectroscopy(FTIR) and Ultraviolet visual(UV/Vis) spectrophotometry. Root sections (10 mm length) were obtained from 53 single-rooted human premolars and chemo-mechanically prepared followed by inoculation with E. faecalis. All the specimens were randomly divided into five groups(n = 10) and irrigated (Group 1-Saline; Group 2-2.5% Sodium hypochlorite(NaOCl); Group 3-Cur; Group 4-nPD; and Group 5-nPD-Cur) followed by diode irradiation and analysed for reduction in colony-forming units(CFU)/mL, bacterial viability using Confocal Laser Scanning Microscopy(CLSM) and SEM for biofilm disruption. Results were analysed using one-way ANOVA followed by post hoc Tukey's test for pairwise comparison (p < 0.05). nPD-Cur revealed the characteristic absorption patterns. The antimicrobial potency was highest for NaOCl followed by nPD > Cur-nPD > Cur.}, }
@article {pmid39669779, year = {2024}, author = {Torkashvand, N and Kamyab, H and Aarabi, P and Shahverdi, AR and Torshizi, MAK and Khoshayand, MR and Sepehrizadeh, Z}, title = {Evaluating the effectiveness and safety of a novel phage cocktail as a biocontrol of Salmonella in biofilm, food products, and broiler chicken.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1505805}, pmid = {39669779}, issn = {1664-302X}, abstract = {Salmonella is a foodborne pathogen of animal and public health significance. Considering the disadvantages of antibiotics or chemical preservatives traditionally used to eliminate this pathogen, attention has shifted, in recent years, toward biocontrol agents such as bacteriophages, used either separately or in combination to prevent food contamination. However, extensive use of phage-based biocontrol agents in the food industry requires further studies to ensure their safety and efficacy. In the present study, we investigated the effectiveness and safety of phage cocktail, a phage cocktail comprising three pre-characterized Salmonella phages (vB_SenS_TUMS_E4, vB_SenS_TUMS_E15 and vB_SenS_TUMS_E19). First, we performed an MTT [3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide] assay on a human foreskin fibroblast cell line, in which the resulting high cell viability revealed the safety of the phage cocktail. Next, we performed a time-kill assay in which a 4 Log decline in bacterial levels was detected. Additionally, we utilized a colorimetric method to evaluate the anti-biofilm activity of phage cocktail, in which it proved more efficacious compared to the MIC and MBEC levels of the antibiotic control. Then, we assessed the ability of phage cocktail to eradicate Salmonella in different food samples, where it considerably reduced the bacterial count regardless of the temperature (4°C and 25°C). Lastly, we used broiler chickens as an animal model to measure the growth-promoting activity of phage cocktail. Salmonella-infected chickens orally treated with modified phage cocktail demonstrated no mortality and a significant increase in weight gain compared to the untreated group (p ≤ 0.0002). The study presents a novel research evaluating the effectiveness and safety of a phage cocktail as a biocontrol agent against Salmonella in various contexts, including biofilms, food products, and broiler chickens. This multifaceted approach underscores the promising role of phage therapy as a sustainable biocontrol strategy in food safety and public health contexts.}, }
@article {pmid39669429, year = {2024}, author = {Chiou, JG and Chou, TK and Garcia-Ojalvo, J and Süel, GM}, title = {Intrinsically robust and scalable biofilm segmentation under diverse physical growth conditions.}, journal = {iScience}, volume = {27}, number = {12}, pages = {111386}, pmid = {39669429}, issn = {2589-0042}, support = {R35 GM139645/GM/NIGMS NIH HHS/United States ; T32 GM127235/GM/NIGMS NIH HHS/United States ; }, abstract = {Developmental patterning is a shared feature across biological systems ranging from vertebrates to bacterial biofilms. While vertebrate patterning benefits from well-controlled homeostatic environments, bacterial biofilms can grow in diverse physical contexts. What mechanisms provide developmental robustness under diverse environments remains an open question. We show that a native clock-and-wavefront mechanism robustly segments biofilms in both solid-air and solid-liquid interfaces. Biofilms grown under these distinct physical conditions differ 4-fold in size yet exhibit robust segmentation. The segmentation pattern scaled with biofilm growth rate in a mathematically predictable manner independent of habitat conditions. We show that scaling arises from the coupling between wavefront speed and biofilm growth rate. In contrast to the complexity of scaling mechanisms in vertebrates, our data suggests that the minimal bacterial clock-and-wavefront mechanism is intrinsically robust and scales in real time. Consequently, bacterial biofilms robustly segment under diverse conditions without requiring cell-to-cell signaling to track system size.}, }
@article {pmid39667852, year = {2025}, author = {Dishan, A and Ozkaya, Y and Temizkan, MC and Barel, M and Gonulalan, Z}, title = {Candida species covered from traditional cheeses: Characterization of C. albicans regarding virulence factors, biofilm formation, caseinase activity, antifungal resistance and phylogeny.}, journal = {Food microbiology}, volume = {127}, number = {}, pages = {104679}, doi = {10.1016/j.fm.2024.104679}, pmid = {39667852}, issn = {1095-9998}, mesh = {*Cheese/microbiology ; *Biofilms/growth &amp; development ; *Virulence Factors/genetics ; *Drug Resistance, Fungal ; *Phylogeny ; *Antifungal Agents/pharmacology ; *Candida albicans/genetics/drug effects/isolation &amp; purification ; Candida/genetics/drug effects/isolation &amp; purification/classification/pathogenicity ; Turkey ; Microbial Sensitivity Tests ; Fungal Proteins/genetics/metabolism ; }, abstract = {This study has provided characterization data (carriage of virulence, antifungal resistance, caseinase activity, biofilm-forming ability and genotyping) of Candida albicans isolates and the occurrence of Candida species in traditional cheeses collected from Kayseri, Türkiye. Phenotypic (E-test, Congo red agar and microtiter plate tests) and molecular tests (identification, virulence factors, biofilm-formation, antifungal susceptibility) were carried out. The phylogenetic relatedness of C. albicans isolates was obtained by constructing the PCA dendrogram from the mass spectra data. Of 102 samples, 13 (12.7%) were found to be contaminated with C. albicans, 15 (14.7%), 10 (9.8%) and five (4.9%) were found to be contaminated with C. krusei, C. lusitane and C. paraplosis, respectively. While seven (16.2%) of 43 Candida spp. isolates were obtained from cheese collected from villages, 36 (83.7%) belonged to cheeses collected from traditional retail stores. The carriage rate of C. albicans isolates belonging to virulence factors HSP90 and PLB1 genes was 30.7%. ALST1, ALST3, BCR, ECE, andHWP (virulence and biofilm-associated) genes were harbored by 30.7%, 23%, 38.4%, 53.8%, and 38.4% of the 13 isolates. According to the microplate test, eight (61.5%) of 13 isolates had strong biofilm production. ERG11 and FKS1 (antifungal resistance genes) were found in 46.1% and 23% of 13 isolates, respectively. Due to missense mutations, K128T, E266D and V488I amino acid changes were detected for some isolates regarding azole resistance. As a result of the E-test, of the 13 isolates, one (7.6%) was resistant to flucytosine, four (30.7%) were resistant to caspofungin, and nine (69.2%) were resistant to fluconazole. The PCA analysis clustered the studied isolates into two major clades. C. albicans isolates of traditional cheese collected from villages were grouped in the same cluster. Among the C. albicans isolates from village cheese, there were those obtained from the same dairy milk at different times. Samples from the same sales points produced at different dairy farms were also contaminated with C. albicans. Concerning food safety standards applied from farm to fork, in order to prevent these pathogenic agents from contaminating cheeses, attention to the hygiene conditions of the sale points, conscious personnel, prevention of cross contamination will greatly reduce public health threats in addition to the application of animal health control, milking hygiene, pasteurization parameters in traditional cheese production.}, }
@article {pmid39667637, year = {2025}, author = {Terzić, J and Stanković, M and Stefanović, O}, title = {Extracts of Achillea millefolium L. inhibited biofilms and biofilm-related virulence factors of pathogenic bacteria isolated from wounds.}, journal = {Microbial pathogenesis}, volume = {199}, number = {}, pages = {107219}, doi = {10.1016/j.micpath.2024.107219}, pmid = {39667637}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Achillea/chemistry ; *Plant Extracts/pharmacology/chemistry ; Humans ; *Anti-Bacterial Agents/pharmacology ; *Virulence Factors ; *Pseudomonas aeruginosa/drug effects ; *Staphylococcus aureus/drug effects ; *Microbial Sensitivity Tests ; Phenols/pharmacology ; Hydrophobic and Hydrophilic Interactions ; Flavonoids/pharmacology ; Spectroscopy, Fourier Transform Infrared ; Bacterial Adhesion/drug effects ; Wound Infection/microbiology/drug therapy ; Bacteria/drug effects ; Wounds and Injuries/microbiology/drug therapy ; Phytochemicals/pharmacology/isolation &amp; purification/chemistry ; }, abstract = {Biofilm is a surface-attached community of bacterial cells implicated in the pathogenesis of chronic infections and is highly resistant to antibiotics. New alternatives for controlling bacterial infections have been proposed focusing on the therapeutic properties of medicinal plants. Achillea millefollium (Yarrow) is a widespread plant species that is widely used in traditional medicine, especially for wound healing. Therefore, the purpose of this study was to examine the antibiofilm activity of A. millefolium ethanol, acetone, and ethyl acetate extracts on biofilms of Staphylococcus aureus, Proteus spp. and Pseudomonas aeruginosa strains originating from human wounds. Additionally, the effects of the tested extracts on auto-aggregation, cell surface hydrophobicity, and bacterial motility were evaluated. Phytochemical analysis included FT-IR spectroscopy and spectrophotometric quantification of phenolic compound contents was performed. In a test with crystal violet, the extracts strongly inhibited initial cell attachment and biofilm formation, but the effects on mature biofilms were weaker. The effects were dose- and strain-dependent, which was confirmed by fluorescence microscopy. The acetone extract showed the strongest antibiofilm activity. Biofilms of S. aureus S3 and S2 clinical strains were the most susceptible (inhibition of ≥76 % and ≥72 % at all tested concentrations, respectively). The highest concentration of total flavonoids was measured in the acetone extract (100.01 ± 3.13 mg RUE/g). Additionally, the extracts reduced bacterial auto-aggregation, swimming and swarming motility of some strains but did not disturb bacterial cell hydrophobicity. These results suggest that A. millefolium extracts have potential roles as new antibiofilm agents against human pathogenic bacteria.}, }
@article {pmid39667627, year = {2025}, author = {Kao, C and Zhang, Q and Li, J and Liu, J and Li, W and Peng, Y}, title = {Rapid start-up and metabolic evolution of partial denitrification/anammox process by hydroxylamine stimulation: Nitrogen removal performance, biofilm characteristics and microbial community.}, journal = {Bioresource technology}, volume = {418}, number = {}, pages = {131959}, doi = {10.1016/j.biortech.2024.131959}, pmid = {39667627}, issn = {1873-2976}, mesh = {*Biofilms/drug effects ; *Denitrification/drug effects ; *Hydroxylamine/pharmacology ; *Nitrogen/pharmacology ; Bioreactors ; Bacteria/metabolism/drug effects ; Oxidation-Reduction ; Water Purification/methods ; Nitrites/metabolism ; Wastewater/chemistry ; Anaerobiosis/drug effects ; }, abstract = {Enhanced nitrogen removal by hydroxylamine (NH2OH) on anammox-related process recently received attention. This study investigated the impact of NH2OH on the partial-denitrification/anammox (PDA) biosystem. Results show that NH2OH (≤10 mg N/L) immediately induced nitrite accumulation and provided sufficient NO2[-] to anammox, achieving a 18.1 ± 4.3 % increase of nitrogen removal efficiency compared to the absence of NH2OH. Long-term exposure to NH2OH accelerated the functional microbial community transformation to PDA. Thauera was highly enriched (6.1 % → 26.9 %) along with Candidatus Brocadia increased in the biofilms, which mainly favor the coupling process of nitrate reduction and anammox. Although the migration mechanism of anammox and denitrifier revealed by CLSM-FISH alleviates the adverse effects of NH2OH, the anammox was inhibited when NH2OH exceeding 15 mg N/L through destroying the inner reduction of NO2[-]. These results suggested appropriate NH2OH addition favors the synergy between denitrifying and anammox bacteria, providing a promising option for wastewater treatment.}, }
@article {pmid39667480, year = {2025}, author = {Zhu, Q and Du, Y and Zheng, Y and Hu, Z and Liu, Z and Hu, J and Hou, H}, title = {Quorum quenching inhibits the formation and electroactivity of electrogenic biofilm by weakening intracellular c-di-GMP and extracellular AHL-mediated signal communication.}, journal = {Environmental research}, volume = {266}, number = {}, pages = {120604}, doi = {10.1016/j.envres.2024.120604}, pmid = {39667480}, issn = {1096-0953}, mesh = {*Biofilms/growth &amp; development ; *Quorum Sensing ; *Cyclic GMP/analogs &amp; derivatives/metabolism ; Signal Transduction ; Acyl-Butyrolactones/metabolism ; Geobacter/physiology/metabolism ; }, abstract = {Electrogenic biofilm formation has been shown to be induced by intracellular c-di-GMP signaling and extracellular quorum sensing, but their interactions have been rarely explored. This study explored the effects of quorum quenching (induced by adding acylase) on electrogenic biofilm development and its underlying mechanisms. Quorum quenching impaired the electricity generation and electroactivity of electrogenic biofilms as indicated by dye decolorization rate. It significantly decreased the proportion of typical exoelectrogen Geobacter from 62.0% to 36.5% after 90 days of operation, and enriched some other functional genera (e.g., Dysgonomonas and Sphaerochaeta) to ensure normal physiological function. Moreover, metagenomic analysis revealed that the addition of acylase weakened the potential of chemical communication, as indicated by the decrease in the abundance of genes encoding the production of AHL and c-di-GMP, and the increase in the abundance of aiiA and pvdQ genes (encoding quorum quenching) and cdgC gene (responsible for c-di-GMP breakdown). Functional contribution analysis indicated that Geobacter was a major contributor to hdtS gene (encoding AHL synthesis). These findings demonstrated that quorum quenching adversely impaired not only quorum sensing but also intracellular c-di-GMP signaling, ultimately inhibiting the development of biofilm. This work lays the foundation for regulating electrogenic biofilm development and improving the performance of microbial electrochemical system using signal communication strategy.}, }
@article {pmid39667149, year = {2025}, author = {Datta, DK and Paramban, S and Yazdani, H and Brown, SP and Fischer, S and Salehi, M}, title = {Influence of biofilm and calcium carbonate scaling on lead transport in plastic potable water pipes: A laboratory and molecular dynamics study.}, journal = {Journal of hazardous materials}, volume = {485}, number = {}, pages = {136831}, doi = {10.1016/j.jhazmat.2024.136831}, pmid = {39667149}, issn = {1873-3336}, mesh = {*Calcium Carbonate/chemistry ; *Lead/analysis ; *Water Supply ; *Drinking Water/chemistry ; *Plastics ; *Molecular Dynamics Simulation ; Laboratories ; Surface Properties ; Biomass ; Organic Chemicals/analysis ; Kinetics ; Water Pollutants, Chemical/analysis ; Polyethylene/chemistry ; }, abstract = {This study investigated lead (Pb) transport through new, biofilm-laden, and calcium carbonate-scaled crosslinked polyethylene (PEX-A) and high-density polyethylene (HDPE) potable water pipes. The research focused on Pb accumulation through short-term exposure incidents (6 h) and Pb release for a longer duration (5 d). A mechanistic investigation of the surface morphology variations of plastic pipes following biofilm and scale formation has been conducted. The nanoscale surface asperities in new PEX-A pipes and microscale roughness features in new HDPE pipes supported the differences in biofilm abundance, scale formation, and metal uptake results between these two pipes. Biomass analysis and dissolved organic matter (DOM) quantification using three-dimensional excitation emission spectroscopy revealed a greater release of biofilm biomass during the Pb accumulation and release experiments from biofilm-laden HDPE pipes. Both biofilm-laden plastic pipes accumulated a significantly greater level of Pb compared to the new and scaled pipes. However, scaled pipes showed the highest Pb release, while biofilm-laden pipes released the least. Additionally, investigation of Pb[2+] exchange from the pipe surface in the presence of Ca[2+] in the solution indicated that divalent cations in water can trigger further Pb release from the pipe surface. Furthermore, the molecular dynamics simulation provided valuable insights into the interaction between different pipe surfaces with Pb with respect to affinity and binding energy.}, }
@article {pmid39665083, year = {2024}, author = {De Jesus, R and Iqbal, S and Mundra, S and AlKendi, R}, title = {Heterogenous bioluminescence patterns, cell viability, and biofilm formation of Photobacterium leiognathi strains exposed to ground microplastics.}, journal = {Frontiers in toxicology}, volume = {6}, number = {}, pages = {1479549}, pmid = {39665083}, issn = {2673-3080}, abstract = {Microplastics (MPs) have been detected in various aquatic environments and negatively affect organisms, including marine luminous bacteria. This study investigated the differences in bioluminescence patterns, cell viability, and biofilm formation of Photobacterium leiognathi strains (LB01 and LB09) when exposed to various concentrations of ground microplastics (GMPs; 0.25%, 0.50%, 1%, or 2% [w/v] per mL) at 22°C or 30°C for 3.1 days (75 h) and 7 days. The strains exhibited heterogenous responses, including variable bioluminescence patterns, cell viability, and biofilm formation, due to the GMPs having effects such as hormesis and bioluminescence quenching. Moreover, the bioluminescence and cell viability differed between the two strains, possibly involving distinct cellular mechanisms, suggesting that GMPs affect factors that influence quorum sensing. Furthermore, the biofilm formation of LB01 and LB09 was observed following exposure to GMPs. Both strains showed increased biofilm formation at higher GMP concentrations (1% and 2%) after 3.1 days at 30°C and 22°C. However, in the 7-day experiment, LB01 significantly (p < 0.05) increased biofilms at 22°C, while LB09 significantly (p < 0.05) produced biofilms at 30°C. These findings highlight the strain-specific responses of Phb. leiognathi to MP pollutants. Therefore, this study underscores the importance of evaluating MPs as environmental stressors on marine microorganisms and their role in the ecophysiological repercussions of plastic pollution in aquatic environments.}, }
@article {pmid39664965, year = {2024}, author = {Qiu, Z and Ran, J and Yang, Y and Wang, Y and Zeng, Y and Jiang, Y and Hu, Z and Zeng, Z and Peng, J}, title = {OmpH is Involved in the Decrease of Acinetobacter baumannii Biofilm by the Antimicrobial Peptide Cec4.}, journal = {Drug design, development and therapy}, volume = {18}, number = {}, pages = {5795-5810}, pmid = {39664965}, issn = {1177-8881}, mesh = {*Biofilms/drug effects ; *Acinetobacter baumannii/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Microbial Sensitivity Tests ; Antimicrobial Peptides/pharmacology/chemistry ; Bacterial Outer Membrane Proteins/genetics/metabolism ; }, abstract = {PURPOSE: The emergence of carbapenem-resistant Acinetobacter baumannii (CRAB) poses great difficulties in clinical treatment, and has been listed by the World Health Organization as a class of pathogens in urgent need of new antibiotic development. In our previous report, the novel antimicrobial peptide Cec4 showed great potential in decreasing the clinical CRAB biofilm, but its mechanism of action is still illusive. Therefore, in order to evaluate the clinical therapeutic potential of Cec4, it is necessary to explore the mechanism of how Cec4 decreases mature biofilms.<br><br>METHODS: Key genes involved in the removal of CRAB biofilms by Cec4 were analyzed using transcriptomics. Based on the results of the bioinformatics analysis, the CRISPR-Cas9 method was used to construct the deletion strain of the key gene. The pYMAb2 plasmid was used for the complementation strain construction. Finally, the roles of key genes in biofilm removal by Cec4 were determined by crystal violet staining, podocyte staining, laser confocal imaging, and MBC and MBEC50.<br><br>RESULTS: Combined with transcriptome analysis, we hypothesized that OmpH is a key gene involved in the removal of CRAB biofilms by Cec4. Deletion of the OmpH gene did not affect A. baumannii growth, but decreased A. baumannii capsule thickness, increasing biofilm production, and made biofilm-state A. baumannii more sensitive to Cec4.<br><br>CONCLUSION: Cec4 decreases biofilms formed by CRAB targeting OmpH. Deletion of the OmpH gene results in an increase in biofilms and greater sensitivity to Cec4, which enhances the removal of A. baumannii biofilms by Cec4.}, }
@article {pmid39664834, year = {2024}, author = {Bhamare, SA and Dahake, PT and Kale, YJ and Dadpe, MV and Kendre, SB}, title = {Effect of Herbal Extract of Spilanthes acmella and Cinnamon Oil on Enterococcus faecalis Biofilm Eradication: An In Vitro Study.}, journal = {International journal of clinical pediatric dentistry}, volume = {17}, number = {9}, pages = {1004-1013}, pmid = {39664834}, issn = {0974-7052}, abstract = {INTRODUCTION: Enterococcus faecalis has a pathogenic role in failed endodontic treatments. The study aimed to assess the efficiency of Spilanthes acmella (SA) and cinnamon oil (CO) extract on E. faecalis biofilm eradication.<br><br>MATERIALS AND METHODS: The antibacterial efficacy of SA and CO against E. faecalis was assessed by the tests of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), and further, the interaction with agents was evaluated at different time intervals by a time-kill assay. The inhibition efficacy of both agents was determined by biofilm adhesion reduction crystal violet assay.<br><br>RESULTS: The MIC of SA was 25 &#x3bc;g/mL, and for CO, it was 12.5 &#x3bc;g/mL. The time-kill assay revealed that antibacterial efficacy was identified till 36 hours by both the test materials. The mean biofilm reduction at 25 &#xb5;g/mL of calcium hydroxide [Ca(OH)2], SA, and CO was 1.53 &#xb1; 0.05, 1.83 &#xb1; 1.57, and 2.06 &#xb1; 0.05, respectively.<br><br>CONCLUSION: SA and CO demonstrated promising antibacterial efficacy against E. faecalis and CO presented significant eradication of biofilms compared to SA.<br><br>HOW TO CITE THIS ARTICLE: Bhamare SA, Dahake PT, Kale YJ, et al. Effect of Herbal Extract of Spilanthes acmella and Cinnamon Oil on Enterococcus faecalis Biofilm Eradication: An In Vitro Study. Int J Clin Pediatr Dent 2024;17(9):1004-1013.}, }
@article {pmid39664828, year = {2024}, author = {Fernandes, RM and Kumar, S and Suvarna, R and Shastry, RP and Sargod, S and Bhat, SS and Manoj, K}, title = {Surface Prereacted Glass Ionomer Varnish as a Multifaceted Anticaries Agent: Investigating its Inhibitory Effects on Demineralization and Biofilm Formation on Primary Tooth Enamel.}, journal = {International journal of clinical pediatric dentistry}, volume = {17}, number = {9}, pages = {1049-1056}, pmid = {39664828}, issn = {0974-7052}, abstract = {BACKGROUND: Dental caries remains a significant oral health concern, particularly in young children. With an increasing interest in preventive strategies, pediatric and preventive dentistry research is now more focused on developing newer materials and techniques to coat the primary teeth to prevent the onset of new carious lesions. While traditional preventive measures such as fluoride application and sealants have been effective in reducing caries incidence, there is still a need for innovative approaches.<br><br>AIM: To evaluate the effectiveness of surface prereacted glass ionomer (S-PRG) light-cured varnish in inhibiting demineralization of primary teeth enamel.<br><br>MATERIALS AND METHODS: In this study, primary teeth samples were randomly divided into two groups: the control group received no coating, while the test group received an S-PRG filler coat. The samples were allowed to demineralize, and various analyses, including Fourier transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM), energy-dispersive X-ray analysis (EDX), and Vickers microhardness analysis, were conducted. Additionally, biofilms of Streptococcus mutans and Enterococcus faecalis were developed on solid surfaces such as microtiter plates, glass, and dentures, and the quantity of bacterial biofilm was measured using crystal violet assay and fluorescence microscopy.<br><br>RESULTS: The study results showed that the primary teeth samples in both groups had a significantly greater calcium content than the controls. The S-PRG group demonstrated a significant reduction in the development of biofilms of S. mutans and E. faecalis, as well as bacterial attachment to glass and denture surfaces compared to the control group, as indicated by crystal violet assay and fluorescence microscopy.<br><br>CONCLUSION: The findings of this study suggest that S-PRG filler-containing coating materials have the potential to prevent demineralization and inhibit S. mutans and E. faecalis biofilm formation on primary tooth enamel.<br><br>CLINICAL SIGNIFICANCE: These results are promising and may have implications for the prevention of dental caries in young children.<br><br>HOW TO CITE THIS ARTICLE: Fernandes RM, Kumar S, Suvarna R, et al. Surface Prereacted Glass Ionomer Varnish as a Multifaceted Anticaries Agent: Investigating its Inhibitory Effects on Demineralization and Biofilm Formation on Primary Tooth Enamel. Int J Clin Pediatr Dent 2024;17(9):1049-1056.}, }
@article {pmid39663366, year = {2024}, author = {Zhao, Q and Wang, R and Song, Y and Lu, J and Zhou, B and Song, F and Zhang, L and Huang, Q and Gong, J and Lei, J and Dong, S and Gu, Q and Borriss, R and Gao, X and Wu, H}, title = {Pyoluteorin-deficient Pseudomonas protegens improves cooperation with Bacillus velezensis, biofilm formation, co-colonizing, and reshapes rhizosphere microbiome.}, journal = {NPJ biofilms and microbiomes}, volume = {10}, number = {1}, pages = {145}, pmid = {39663366}, issn = {2055-5008}, support = {31972325, 32172490//National Natural Science Foundation of China (National Science Foundation of China)/ ; }, mesh = {*Bacillus/genetics/metabolism/physiology ; *Pseudomonas/genetics/metabolism/physiology ; *Rhizosphere ; *Biofilms/growth &amp; development ; *Solanum lycopersicum/microbiology ; *Phenols/metabolism ; Plant Roots/microbiology ; Pyrroles/metabolism ; Microbiota ; Plant Diseases/microbiology ; Soil Microbiology ; Microbial Interactions ; }, abstract = {Plant-beneficial Pseudomonas and Bacillus have been extensively studied and applied in biocontrol of plant diseases. However, there is less known about their interaction within two-strain synthetic communities (SynCom). Our study revealed that Pseudomonas protegens Pf-5 inhibits the growth of several Bacillus species, including Bacillus velezensis. We established a two-strain combination of Pf-5 and DMW1 to elucidate the interaction. In this combination, pyoluteorin conferred the competitive advantage of Pf-5. Noteworthy, pyoluteorin-deficient Pf-5 cooperated with DMW1 in biofilm formation, production of metabolites, root colonization, tomato bacterial wilt disease control, as well as in cooperation with beneficial bacteria in tomato rhizosphere, such as Bacillus spp. RNA-seq analysis and RT-qPCR also proved the pyoluteorin-deficient Pf-5 mutant improved cell motility and metabolite production. This study suggests that the cooperative effect of Bacillus-Pseudomonas consortia depends on the balance of pyoluteorin. Our finding needs to be considered in developing efficient SynCom in sustainable agriculture.}, }
@article {pmid39660862, year = {2025}, author = {Sangha, JS and Gogulancea, V and Curtis, TP and Jakubovics, NS and Barrett, P and Metris, A and Ofiţeru, ID}, title = {Advancing dental biofilm models: the integral role of pH in predicting S. mutans colonization.}, journal = {mSphere}, volume = {10}, number = {1}, pages = {e0074324}, pmid = {39660862}, issn = {2379-5042}, support = {EP/R51309X/1//UKRI | Engineering and Physical Sciences Research Council (EPSRC)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Streptococcus mutans/growth &amp; development/physiology ; Hydrogen-Ion Concentration ; Glucose/metabolism ; Models, Theoretical ; Dental Caries/microbiology ; Lactic Acid/metabolism ; Humans ; Models, Biological ; Culture Media/chemistry ; }, abstract = {Mathematical models can provide insights into complex interactions and dynamics within microbial communities to complement and extend experimental laboratory approaches. For dental biofilms, they can give a basis for evaluating biofilm growth or the transition from health to disease. We have developed mathematical models to simulate the transition toward a cariogenic microbial biofilm, modeled as the overgrowth of Streptococcus mutans within a five-species dental community. This work builds on experimental data from a continuous flow reactor with hydroxyapatite coupons for biofilm growth, in a chemically defined medium with varying concentrations of glucose and lactic acid. The biofilms formed on the coupons were simulated using individual-based models (IbMs), with bacterial growth modeled using experimentally measured kinetic parameters. The IbM assumes that the maximum theoretical growth yield for biomass is dependent on the local concentration of reactants and products, while the growth rates were described using traditional Monod equations. We have simulated all the conditions studied experimentally, considering different initial relative abundance of the five species, and also different initial clustering in the biofilm. The simulation results only reproduced the experimental dominance of S. mutans at high glucose concentration after we considered the species-specific effect of pH on growth rates. This highlights the significance of the aciduric property of S. mutans in the development of caries. Our study demonstrates the potential of combining in vitro and in silico studies to gain a new understanding of the factors that influence dental biofilm dynamics.IMPORTANCEWe have developed in silico models able to reproduce the relative abundance measured in vitro in the synthetic dental biofilm communities growing in a chemically defined medium. The advantage of this combination of in vitro and in silico models is that we can study the influence of one parameter at a time and aim for direct validation. Our work demonstrates the utility of individual-based models for simulating diverse conditions affecting dental biofilm scenarios, such as the frequency of glucose intake, sucrose pulsing, or integration of pathogenic or probiotic species. Although in silico models are reductionist approaches, they have the advantage of not being limited in the scenarios they can test by the ethical consideration of an in vivo system, thus significantly contributing to dental biofilm research.}, }
@article {pmid39659667, year = {2024}, author = {Kendra, S and Czucz Varga, J and Gaálová-Radochová, B and Bujdáková, H}, title = {Practical application of PMA-qPCR assay for determination of viable cells of inter-species biofilm of Candida albicans-Staphylococcus aureus.}, journal = {Biology methods &amp; protocols}, volume = {9}, number = {1}, pages = {bpae081}, pmid = {39659667}, issn = {2396-8923}, abstract = {Determining the number of viable cells by calculating colony-forming units is time-consuming. The evaluation of mixed biofilms consisting of different species is particularly problematic. Therefore, the aim of this study was to optimize a molecular method-propidium monoazide quantitative polymerase chain reaction (PMA-qPCR)-for accurate and consistent differentiation between living and dead cells. In the practical experimental example, the number of genome copies representing living cells was determined in a mixed biofilm of Candida albicans-Staphylococcus aureus inhibited by photodynamic inactivation. Optimal conditions such as PMA concentration and the duration of light exposure, the optimization of DNA isolation from the mixed biofilm and standardization of PMA-qPCR parameters were tested prior to the main experiment. The genome copy number was calculated based on the known amount of genomic DNA in the qPCR and the genome size of the respective microorganism. The results showed that photodynamic inactivation in the presence of 1 mM methylene blue decreased the total genome copy number from 1.65 × 10[8] to 3.19 × 10[7], and from 4.39 × 10[7] to 1.91 × 10[7] for S. aureus and C. albicans (P < 0.01), respectively. The main disadvantage is the overestimation of the number of living cells represented by genome copy numbers. Such cells are unable to reproduce and grow (no vitality) and are continuously dying. On the other hand, PMA-qPCR determines the copy numbers of all microbial species, including a mix of eukaryotic yeasts and prokaryotic bacteria in a biofilm in one step, which is a great advantage.}, }
@article {pmid39657894, year = {2025}, author = {Wang, P and Zeng, Y and Liu, J and Wang, L and Yang, M and Zhou, J}, title = {Antimicrobial and anti-biofilm effects of dihydroartemisinin-loaded chitosan nanoparticles against methicillin-resistant Staphylococcus aureus.}, journal = {Microbial pathogenesis}, volume = {199}, number = {}, pages = {107208}, doi = {10.1016/j.micpath.2024.107208}, pmid = {39657894}, issn = {1096-1208}, mesh = {*Biofilms/drug effects ; *Methicillin-Resistant Staphylococcus aureus/drug effects ; *Chitosan/pharmacology/chemistry ; *Nanoparticles/chemistry ; *Microbial Sensitivity Tests ; *Artemisinins/pharmacology ; *Anti-Bacterial Agents/pharmacology ; Microscopy, Electron, Scanning ; Drug Carriers/chemistry ; Microscopy, Confocal ; }, abstract = {The formation of biofilms enhances bacterial antibiotic resistance, posing significant challenges to clinical treatment. Methicillin-resistant Staphylococcus aureus (MRSA) is a primary pathogen in biofilm-associated infections. Its high antibiotic resistance and incidence rates make it a major clinical challenge, underscoring the urgent need for novel therapeutic strategies. Building on previous research, this study employs nanotechnology to fabricate dihydroartemisinin-chitosan nanoparticles (DHA-CS NPs) and, for the first time, applies them to the treatment of MRSA biofilm infections. The antibacterial and anti-biofilm activities of these compounds were evaluated, and their potential mechanisms of action were preliminarily explored. The results demonstrated that the DHA-CS NPs exhibited a minimum inhibitory concentration (MIC) of15 μg/mLand a minimum bactericidal concentration (MBC) of 30 μg/mL. At 15 μg/mL, the DHA-CS NPs significantly inhibited MRSA biofilm formation (P < 0.001),while at 7.5 μg/mL, they dispersed 67.4 ± 3.77 % of the preformed biofilms (P < 0.001). Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) confirmed the disruption of MRSA biofilms. Mechanistic studies, including phenol-sulfuric acid assays, static biofilm microtiter plate assays, and RT-qPCR, revealed that the DHA-CS NPs inhibited the synthesis of extracellular polymeric substances (EPS), suppressed the release of extracellular DNA (eDNA), and downregulated key biofilm-related genes (icaA, sarA, cidA, and agrA). These findings suggest that DHA-CS NPs hold significant promise for inhibiting and eradicating MRSA biofilms, providing a theoretical basis for the development of novel antibiofilm therapies.}, }
@article {pmid39657876, year = {2025}, author = {Harkai, &#xc1; and Beck, YK and Tory, A and Mészáros, T}, title = {Selection of streptococcal glucan-binding protein C specific DNA aptamers to inhibit biofilm formation.}, journal = {International journal of biological macromolecules}, volume = {288}, number = {}, pages = {138579}, doi = {10.1016/j.ijbiomac.2024.138579}, pmid = {39657876}, issn = {1879-0003}, mesh = {*Aptamers, Nucleotide/pharmacology/chemistry ; *Biofilms/drug effects ; *Streptococcus mutans/drug effects/genetics ; *SELEX Aptamer Technique ; Carrier Proteins/metabolism/genetics ; Bacterial Proteins/genetics/metabolism ; Lectins/pharmacology/chemistry/metabolism ; Protein Binding ; }, abstract = {Streptococcus mutans is a commensal oral bacterium, yet its capacity for extensive biofilm formation is a major contributor to dental caries. This study presents a novel biofilm inhibition strategy by targeting GbpC, a cornerstone protein in S. mutans biofilm architecture, with specific DNA aptamers. Using SELEX (Systematic Evolution of Ligands by EXponential enrichment), we selectively targeted the extracellular domain of GbpC while incorporating structurally similar antigen I/II protein and a GbpC-deficient S. mutans strain as counter-targets to ensure high specificity. Aptamer selection was further refined through a panning method that combined primer-blocked asymmetric PCR with AlphaScreen technology. Detailed binding analyses via biolayer interferometry and microscale thermophoresis confirmed the interaction between top aptamer candidates and GbpC. Functional assays demonstrated that two lead aptamers evidently inhibited biofilm formation in wild-type S. mutans without affecting the GbpC-deficient strain, highlighting the aptamers' specificity. These results confirm that the selected aptamers retain specificity even in the complex bacterial culture matrix, validating the efficacy of our selection approach. Notably, these aptamers represent the first instance of using DNA aptamers to inhibit S. mutans biofilm formation by disrupting glucan binding. These aptamers hold promise as lead molecules for the development of biofilm-targeting therapies in dental care.}, }
@article {pmid39654786, year = {2024}, author = {Aghmiyuni, ZF and Ahmadi, MH and Saderi, H}, title = {Relationship between the strength of biofilm production and the presence of pvl and mecA genes in Staphylococcus aureus isolated from skin and soft tissue infections.}, journal = {Heliyon}, volume = {10}, number = {23}, pages = {e40524}, pmid = {39654786}, issn = {2405-8440}, abstract = {This research sought to investigate the association between the occurrence of the pvl and mecA genes and the strength of biofilm formation, as well as to assess the efficacy of vancomycin and ceftaroline against Staphylococcus aureus strains obtained from skin and soft tissue infections (SSTIs). A total of 134 S. aureus isolates were collected from SSTI patients and identified through standard microbiological techniques. Vancomycin and ceftaroline susceptibility testing were performed using the agar dilution and disc diffusion methods, respectively. PCR analysis was conducted to identify the nuc, mecA, and pvl genes. Biofilm production was measured using the tissue culture plate method. Methicillin-resistant S. aureus (MRSA) represented 58.2 % of the isolates. All isolates displayed biofilm-forming capability, with 10.4 % classified as high-grade biofilm producers, 85.7 % of which were positive for the mecA gene (P = 0.02). 16.4 % of the isolates had pvl gene and 59 % of PVL-positive strains identified as MRSA. Most of the low-grade biofilm producers had the pvl gene (P = 0.03). Vancomycin susceptibility was observed in 98.5 % of isolates, with an MIC50 of 1 μg/mL in 51.4 % of cases. Among MRSA strains, 1.4 % exhibited intermediate resistance to vancomycin, with MICs between 4 and 8 μg/mL. No resistance to ceftaroline was found. The results demonstrate a significant association between biofilm production strength and the occurrence of the mecA and pvl genes; mecA correlated with increased biofilm production, while pvl was associated with lower biofilm levels. These findings offer valuable insights for future studies, suggesting that ceftaroline could be an effective alternative to vancomycin for treating MRSA-related SSTIs, particularly given the increasing resistance to vancomycin.}, }
@article {pmid39654682, year = {2024}, author = {Nandanwar, N and Gu, G and Gibson, JE and Neely, MN}, title = {Polymicrobial interactions influence Mycobacterium abscessus co-existence and biofilm forming capabilities.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1484510}, pmid = {39654682}, issn = {1664-302X}, abstract = {The lungs of patients with cystic fibrosis (CF) are vulnerable to persistent polymicrobial colonization by bacterial pathogens including Pseudomonas aeruginosa, Staphylococcus aureus, and the non-tuberculous mycobacterium (NTM) Mycobacterium abscessus. The polymicrobial milieu within the CF lung impacts individual species fitness, influences biofilm-forming capabilities, pathogenicity, production of virulence factors and even antimicrobial responses, all potentially compromising therapeutic success. Interaction studies among these CF pathogens are very limited, especially studies on the influences of P. aeruginosa and S. aureus on M. abscessus co-existence and virulence. Based on the little known thus far about coinfection of these pathogens, we hypothesize that the co-existence of P. aeruginosa and S. aureus alters M. abscessus virulence and phenotypic characteristics. We evaluated the direct (co-culture) and indirect (using supernatant) effects of P. aeruginosa and S. aureus on M. abscessus growth rate, biofilm formation, macrophage internalization and glycopeptidolipids (GPL) expression. Our observations indicate that P. aeruginosa and S. aureus exert a competitive behavior toward M. abscessus during direct contact or indirect interaction in-vitro, probably as is the case of polymicrobial infections in the lungs of patients with CF. This is the first report that demonstrates S. aureus inhibitory effects on M. abscessus growth and biofilm forming capabilities. Collectively, co-culture studies enhance our understanding of polymicrobial interactions during coinfection and can guide to establish better management of coinfections and treatment strategies for M. abscessus.}, }
@article {pmid39653175, year = {2025}, author = {Wei, Y and Xia, W and Qian, Y and Rong, C and Ye, M and Chen, Y and Kikuchi, J and Li, YY}, title = {Revealing microbial compatibility of partial nitritation/Anammox biofilm from sidestream to mainstream applications: Origins, dynamics, and interrelationships.}, journal = {Bioresource technology}, volume = {418}, number = {}, pages = {131963}, doi = {10.1016/j.biortech.2024.131963}, pmid = {39653175}, issn = {1873-2976}, mesh = {*Biofilms ; *Bioreactors/microbiology ; Bacteria/metabolism ; Ammonium Compounds/metabolism ; Sewage/microbiology ; Nitrogen ; Oxidation-Reduction ; }, abstract = {Biofilms offer a solution to the challenge of low biomass retention faced in mainstream partial nitritation/Anammox (PN/A) applications. In this study, a one-stage PN/A reactor derived from initial granular sludge was successfully transformed into a biofilm system using shedding carriers. Environmental stressors, such as ammonium nitrogen concentration and organic matter, significantly affected the competitive dynamics and dominant species composition between Ca. Kuenenia and Ca. Brocadia. Under approximately 500 mg/L NH4[+]-N, Ca. Brocadia emerged as the dominant anammox bacteria species, but was subsequently replaced by Ca. Kuenenia in the presence of approximately 54 mg COD/L CH3COONa. Moreover, Chloroflexi species on the original biofilm exhibited an associated relationship with the growth of Ca. Kuenenia in new biofilm. The biofilm assembly and microbial community migration uniquely reveal the microbial niche dynamics. This study provides valuable insights for PN/A biofilm applications facing diverse challenges of environmental stresses in the transition from sidestream to mainstream.}, }
@article {pmid39651958, year = {2024}, author = {Werlang, CA and Sahoo, JK and Cárcarmo-Oyarce, G and Stevens, C and Uzun, D and Putnik, R and Hasturk, O and Choi, J and Kaplan, DL and Ribbeck, K}, title = {Selective Biofilm Inhibition through Mucin-Inspired Engineering of Silk Glycopolymers.}, journal = {Journal of the American Chemical Society}, volume = {146}, number = {50}, pages = {34661-34668}, doi = {10.1021/jacs.4c12945}, pmid = {39651958}, issn = {1520-5126}, mesh = {*Biofilms/drug effects ; *Mucins/chemistry/metabolism ; *Streptococcus mutans/drug effects ; *Silk/chemistry ; Humans ; Streptococcus sanguis/drug effects ; Streptococcus/drug effects/chemistry ; }, abstract = {Mucins are key components of innate immune defense and possess remarkable abilities to manage pathogenic microbes while supporting beneficial ones and maintaining microbial homeostasis at mucosal surfaces. Their unique properties have garnered significant interest in developing mucin-inspired materials as novel therapeutic strategies for selectively controlling pathogens without disrupting the overall microbial ecology. However, natural mucin production is challenging to scale, driving the need for simpler materials that reproduce mucin's bioactivity. In this work, we generated silk-based glycopolymers with different monosaccharides (GalNAc, GlcNAc, NeuNAc, GlcN, and GalN) and different grafting densities. Using the oral cavity as a model system, we treated in vitro cultures of pathogenic Streptococcus mutans and commensal Streptococcus sanguinis with our glycopolymers, finding that silk-tethered GalNAc uniquely prevented biofilm formation without affecting overall bacterial growth of either species. This relatively simple material reproduced mucin's virulence-neutralizing effects while maintaining biocompatibility. These mucin-inspired materials represent a valuable tool for preventing infection-related harm and offer a strategy for the domestication of pathogens in other environments.}, }
@article {pmid39649128, year = {2024}, author = {Jones, L and Salta, M and Skovhus, TL and Thomas, K and Illson, T and Wharton, J and Webb, J}, title = {Dual anaerobic reactor model to study biofilm and microbiologically influenced corrosion interactions on carbon steel.}, journal = {Npj Materials degradation}, volume = {8}, number = {1}, pages = {125}, pmid = {39649128}, issn = {2397-2106}, abstract = {Continual challenges due to microbial corrosion are faced by the maritime, offshore renewable and energy sectors. Understanding the biofilm and microbiologically influenced corrosion interaction is hindered by the lack of robust and reproducible physical models that reflect operating environments. A novel dual anaerobic biofilm reactor, using a complex microbial consortium sampled from marine littoral sediment, allowed the electrochemical performance of UNS G10180 carbon steel to be studied simultaneously in anaerobic abiotic and biotic artificial seawater. Critically, DNA extraction and 16S rRNA amplicon sequencing demonstrated the principal biofilm activity was due to electroactive bacteria, specifically sulfate-reducing and iron-reducing bacteria.}, }
@article {pmid39648406, year = {2024}, author = {Geng, F and Liu, J and Liu, J and Lu, Z and Pan, Y}, title = {Recent progress in understanding the role of bacterial extracellular DNA: focus on dental biofilm.}, journal = {Critical reviews in microbiology}, volume = {}, number = {}, pages = {1-19}, doi = {10.1080/1040841X.2024.2438117}, pmid = {39648406}, issn = {1549-7828}, abstract = {Dental biofilm is a highly complicated and dynamic structure comprising not only microbial communities but also the surrounding matrix of extracellular polymeric substances (EPS), including polysaccharides, proteins, extracellular DNA (eDNA) and other biopolymers. In recent years, the important role of bacterial eDNA in dental biofilms has gradually attracted attention. In this review, we present recent studies on the presence, dynamic conformation and release of oral bacterial eDNA. Moreover, updated information on functions associated with oral bacterial eDNA in biofilm formation, antibiotic resistance, activation of the immune system and immune evasion is highlighted. Finally, we summarize the role of oral bacterial eDNA as a promising target for the treatment of oral diseases. Increasing insight into the versatile roles of bacterial eDNA in dental biofilms will facilitate the prevention and treatment of biofilm-induced oral infections.}, }
@article {pmid39647771, year = {2025}, author = {Chen, R and Xu, R and Huang, J and Zhu, X and Tang, Y and Zhang, Y}, title = {N-acyl-homoserine-lactones as a critical factor for biofilm formation during the initial adhesion stage in drinking water distribution systems.}, journal = {Environmental pollution (Barking, Essex : 1987)}, volume = {366}, number = {}, pages = {125489}, doi = {10.1016/j.envpol.2024.125489}, pmid = {39647771}, issn = {1873-6424}, mesh = {*Biofilms ; *Drinking Water/microbiology/chemistry ; *Quorum Sensing ; *Acyl-Butyrolactones/metabolism ; Water Supply ; Stainless Steel ; }, abstract = {The N-acyl-homoserine-lactone (AHLs)-mediated quorum sensing (QS) system is crucial for the coordination of microbial behaviors within communities. However, the levels of AHLs in biofilms in drinking water distribution systems (DWDSs) and their impact on biofilm formation remain poorly understood. Herein, we simulated DWDSs via biofilm reactors to explore the presence and influence of AHLs during the initial stages of biofilm formation on pipe walls. Glass, polypropylene random copolymer (PP-R) and stainless steel (SS) were used as the coupon materials and the three parallel experimental groups were set up and named accordingly. The glass material is considered to form biofilms only minimally and is therefore used as a negative control. By day 30, the concentration of AHLs in biofilm phase in both PP-R group and SS group reached 1200-1800 ng/L. The predominant AHLs were C6-HSL, C8-HSL, and C10-HSL, with a significant positive correlation between AHLs and biofilm biomass. Metagenomic analysis revealed that microbes exhibiting significant differences among the three groups all demonstrated notable correlations with AHLs. Subsequent analysis of QS genes revealed that the genes associated with AHLs biosynthesis and QS receptors were more abundant in the PP-R and SS groups with biofilm formation. Additionally, we analyzed the abundance of genes related to cell motility, transmembrane transport, tricarboxylic acid cycle, and genetic information synthesis. The co-occurrence network indicates that these processes exhibit a strong correlation with QS genes. This study demonstrates the pivotal role of AHLs in microbial communication during the initial stages of biofilm formation in DWDSs and indicates that the regulatory pathways and mechanisms of AHLs may vary under different environmental conditions.}, }
@article {pmid39647662, year = {2024}, author = {Kato, H and Yoshida, H and Saito, M and Hashizume-Takizawa, T and Negishi, S and Senpuku, H}, title = {Assessment of biofilm formation on ceramic, metal, and plastic brackets in orthodontic materials by new method using renG-expressing Streptococcus mutans.}, journal = {Journal of oral biosciences}, volume = {}, number = {}, pages = {100594}, doi = {10.1016/j.job.2024.100594}, pmid = {39647662}, issn = {1880-3865}, abstract = {OBJECTIVE: Oral biofilm has a high acid-producing capacity, increases the risk of enamel demineralization around brackets, and has been identified as a problem in orthodontic treatment. Here, we assessed the risk of biofilm formation by Streptococcus mutans, which is associated with the development of white spot lesions (WSL) on tooth surfaces, using multibracket devices.<br><br>METHODS: Various types of brackets were used for the biofilm formation assay with S. mutans coated with human saliva, immersed in renG-expressing S. mutans UA159 (strain with the luciferase gene inserted), and incubated overnight at 37&#xb0;C under aerobic conditions containing 5% CO2. The biofilm was washed twice with phosphate-buffered saline (PBS), and 200 &#x3bc;L of luciferin dissolved in PBS was added to each well. The mixture was light shielded and allowed to react for 20 min. Luminescence was measured as the amount of biofilm formed by live cells on the bracket surfaces using an optical emission spectrophotometer.<br><br>RESULTS: Biofilm formation was greater in plastic brackets than in ceramic and metal brackets in a number-dependent manner. However, biofilm formation was inhibited as the plastic bracket was coated with saliva.<br><br>CONCLUSION: For preventive treatments of WSL onset during orthodontic treatment, orthodontists should carefully select and customize brackets based on patient needs, goals, and biomechanical principles. This study developed a new measurement method using renG-expressing S. mutans UA159 to accurately assess active biofilm formation on bracket surfaces.}, }
@article {pmid39645169, year = {2025}, author = {da Silva, ARP and Costa, MDS and Araújo, NJS and de Freitas, TS and Paulo, CLR and de Alencar, MAS and Barbosa-Filho, JM and Andrade-Pinheiro, JC and Coutinho, HDM}, title = {Evaluation of inhibition and eradication of bacterial biofilm by solasodin.}, journal = {The Journal of steroid biochemistry and molecular biology}, volume = {247}, number = {}, pages = {106654}, doi = {10.1016/j.jsbmb.2024.106654}, pmid = {39645169}, issn = {1879-1220}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Staphylococcus aureus/drug effects ; *Anti-Bacterial Agents/pharmacology ; *Pseudomonas aeruginosa/drug effects ; *Microbial Sensitivity Tests ; *Enterococcus faecalis/drug effects/growth &amp; development ; *Gentamicins/pharmacology ; *Solanaceous Alkaloids/pharmacology ; Chlorhexidine/pharmacology/analogs &amp; derivatives ; Norfloxacin/pharmacology ; Ampicillin/pharmacology ; Humans ; }, abstract = {Biofilms are complex microbial structures that have a significant impact on human health, industry and the environment. These complex structures represent one of the main mechanisms of microbial resistance, and their development constitutes a serious health problem. Therefore, the aim of this study was to verify the potential for inhibition and eradication of bacterial biofilm by salosodine, which is a steroidal alkaloid sapogenin found in plants of the Solanum genus. The antibiotics gentamicin, norfloxacin, ampicillin and the antiseptic agent chlorhexidine gluconate were used as positive controls to compare the results. Solasodin showed significant results in inhibiting the formation of Enterococcus faecalis and Staphylococcus aureus biofilms at the two concentrations tested. And when comparing the effect of solasodine for the two concentrations and the effect of the antibiotic gentamicin, it was found that sapogenin showed a better percentage in inhibiting E. faecalis biofilm formation. And against Pseudomonas aeruginosa, solasodine only inhibited biofilm formation at the highest concentration compared to the control. In the biofilm eradication results, solasodine showed a significant reduction in the biomass of the S. aureus biofilm, and when compared with the percentage reduction of the antibiotics, solasodine showed a relevant result for both concentrations. Only at the lowest concentration did solasodine show a reduction in P. aeruginosa biofilm biomass, a reduction close to that of chlorhexidine gluconate. In terms of activity, solasodine has been shown to have the potential to inhibit biofilm formation. However, further tests are needed to investigate the mechanisms of action of this sapogenin on the bacterial biofilms tested.}, }
@article {pmid39644415, year = {2024}, author = {Wozeak, DR and Pereira, IL and Cardoso, TL and Neto, ACPS and Hartwig, DD}, title = {Genetic diversity, drug resistance, and biofilm formation in Klebsiella pneumoniae associated with nosocomial infection in Pelotas, RS, Brazil.}, journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]}, volume = {}, number = {}, pages = {}, pmid = {39644415}, issn = {1678-4405}, abstract = {Antibiotic resistance and the potential persistence of Klebsiella pneumoniae strains in hospital environments is an important challenge for human medicine. This research aims to detect resistance to antibiotics, biofilm formation, and the genetic pattern among clinical isolates associated with nosocomial infection obtained from a university hospital in the city of Pelotas, RS, Brazil. Twenty-eight isolates were identified at the species level by polymerase chain reaction (PCR) and were characterized regarding the profile of biofilm formation and antibiotic resistance. The genetic relationship was determined through pulsed-field gel electrophoresis (PFGE). The antibiotic resistance profile was made following the standards established by CLSI. All clinical isolates included in this study were confirmed as belonging to the species K. pneumoniae, 96.42% were considered strong biofilm formers and all were positive in the Congo Red agar (CRA) test. Thus, 64.29% of isolates were classified as multidrug-resistant (MDR), 25% as extensively drug-resistant (XDR), and 7.14% as pandrug-resistant (PDR). PFGE fingerprint analysis revealed 18 clones and of these, 15 have a unique pattern and another three were groups with patterns > 80% similarity. The clinical isolates used were collected over two years and revealed a genetic relationship. The same clone was identified in different types of samples and different years, demonstrating the permanence of the strain in the hospital environment. Our results reaffirm the need for greater measures of control and disinfection within the hospital environment, and the priority of therapeutic measures to contain the propagation of K. pneumoniae.}, }
@article {pmid39644379, year = {2024}, author = {Samreen,  and Ahmad, I}, title = {Antibacterial and anti-biofilm efficacy of 1,4-naphthoquinone against Chromobacterium violaceum: an in vitro and in silico investigation.}, journal = {Archives of microbiology}, volume = {207}, number = {1}, pages = {11}, pmid = {39644379}, issn = {1432-072X}, mesh = {*Biofilms/drug effects ; *Chromobacterium/drug effects/physiology ; *Naphthoquinones/pharmacology/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Microbial Sensitivity Tests ; Molecular Docking Simulation ; Computer Simulation ; Indoles ; }, abstract = {Antimicrobial resistance (AMR) is an urgent worldwide health concern, requiring the exploration for novel antimicrobial interventions. A Gram-negative bacterium, Chromobacterium violaceum, synthesizes quorum-sensing-regulated violacein pigment, develops resilient biofilms, and is often used for the screening of anti-infective drugs. The aim of this work is to assess the antibacterial and antibiofilm properties of three polyphenols: 1,4-naphthoquinone, caffeic acid, and piperine. The determination of antibacterial activity was conducted by the agar overlay and broth microdilution techniques. Analysis of membrane rupture was conducted by crystal violet uptake and β-galactosidase assay. Inhibition of biofilm was evaluated using a 96-well microtiter plate assay. Biofilm structures were visualized using light, scanning electron microscopy (SEM), and confocal laser scanning electron microscopy (CLSM). Among the phytochemicals, 1,4-naphthoquinone exhibited the highest antibacterial action (25 mm zone of inhibition). The minimum inhibitory concentration of 1,4-naphthoquinone was determined to be 405 µM. Outer and inner membrane permeability was enhanced by 52.01% and 1.28 absorbance, respectively. Violacein production was reduced by 74.85%, and biofilm formation was suppressed by 63.25% at sub-MIC levels (202.5 µM). Microscopic analyses confirmed reduced adhesion on surfaces. Hemolytic activity of 1,4-naphthoquinone showed a concentration-dependent effect, with 32.16% haemolysis at 202.5 µM. Molecular docking revealed significant interactions of 1,4-naphthoquinone with DNA gyrase followed by CviR. These findings highlight 1,4-naphthoquinone's potent antibacterial efficacy against C. violaceum, proposing its use as a surface coating agent to prevent biofilm formation on medical devices, thereby offering a promising strategy to combat bacterial infections.}, }
@article {pmid39643335, year = {2024}, author = {Zhao, N and Mei, Y and Hou, X and Yang, M and Li, H and Liao, Q and Zhao, J and Ge, L}, title = {Comparative transcriptomic insight into orchestrating mode of dielectric barrier discharge cold plasma and lactate in synergistic inactivation and biofilm-suppression of Pichia manshurica.}, journal = {Food research international (Ottawa, Ont.)}, volume = {198}, number = {}, pages = {115323}, doi = {10.1016/j.foodres.2024.115323}, pmid = {39643335}, issn = {1873-7145}, mesh = {*Biofilms/growth &amp; development/drug effects ; *Plasma Gases/pharmacology ; *Lactic Acid/metabolism ; *Transcriptome ; *Pichia/genetics/physiology/metabolism ; Food Microbiology ; }, abstract = {Pichia manshurica is a representative species of biofilm-forming yeasts which usually induces the spoilage of fermented food. This study aims to investigate the synergistic inactivating and anti-biofilm effect of dielectric barrier discharge cold plasma (DBD) and lactate on Pichia manshurica (P. manshurica) and the underlying mechanism by comparison of survival rate, growth curve, biofilm-forming capacity and transcriptome of P. manshurica treated with control (CK), lactate (LA), DBD, and combination of DBD and lactate (DBD-LA). Results showed that CK and LA hardly influenced the growth and biofilm formation of P. manshurica. DBD and DBD-LA reduced survival rate to 35 % and 10 % immediately after treatment, respectively. Also, with growth curve remaining plateau, DBD-LA completely inhibited the growth and biofilm formation of P. manshurica, while DBD moderately reduced the growth density and biofilm. Comparative transcriptomic analysis revealed that single DBD treatment intervened in the functions and pathways associated with DNA replication and cell adhesion (down-regulated expression of flocculation protein-related genes and up-regulated expression of β-1,4-D-glucan cellobiohydrolase-related genes). Lactate reinforced the inactivating and anti-biofilm effect of DBD by stimulating redox reaction and suppressing functions and pathways involving synthesis and metabolism of lipid and membrane, cation binding and organelle assembly. This study demonstrated the potential of synergistic combination of DBD and lactate in efficient control of biofilm-related spoilage of food by yeast.}, }
@article {pmid39642791, year = {2025}, author = {Wang, J and Sun, Y and Khunjar, W and Pace, G and McGrath, M and Chitrakar, S and Taylor, RL and Carroll, JR and Zhang, X and Wang, ZW}, title = {Mechanistic understanding of the performance difference between methanol- and glycerol-fed partial denitrification anammox in tertiary moving bed biofilm reactors treating real secondary effluent.}, journal = {Water research}, volume = {271}, number = {}, pages = {122893}, doi = {10.1016/j.watres.2024.122893}, pmid = {39642791}, issn = {1879-2448}, mesh = {*Bioreactors ; *Glycerol/metabolism ; *Biofilms ; *Denitrification ; *Methanol ; *Waste Disposal, Fluid ; Wastewater/chemistry ; Nitrogen ; Nitrites/metabolism ; Water Purification ; Oxidation-Reduction ; Anaerobiosis ; }, abstract = {Two pilot-scale tertiary moving bed biofilm reactor (MBBR) treatment trains were operated onsite for 371 days in a local wastewater treatment plant (WWTP) to compare their treatment performance and mechanistic difference when methanol and glycerol were used as carbon sources, respectively. Both trains were able to meet the tertiary effluent total inorganic nitrogen (TIN) requirement of < 3 mg/L, with 31.6% ∼ 46.3 % methanol savings or 30.9 % ∼ 43.8 % glycerol savings over full denitrification projected at influent dissolved oxygen in the range of 0∼3 mg/L. Very different nitrite provision mechanism was found between the two types of carbon sources, i.e., the nitrite sink by anammox through its outcompetition of dentification was the major source of nitrite provision mechanism for anammox bacteria when methanol was used as a carbon; while the rate differential between denitratation and denitritation was the major nitrite source when glycerol was used as a carbon. The cause of this mechanistic discrepancy can be ascribed to the dramatic different half-saturation constants between the two types of carbon sources (e.g., half saturation constant of glycerol was 1.7 times that of methanol). This study provided fundamental understandings that can be used to reconcile the controversy over whether methanol is suitable for partial denitrification anammox in low strength wastewater treatment.}, }
@article {pmid39640770, year = {2024}, author = {Ullah, MA and Islam, MS and Ferdous, FB and Rana, ML and Hassan, J and Rahman, MT}, title = {Assessment of prevalence, antibiotic resistance, and virulence profiles of biofilm-forming Enterococcus faecalis isolated from raw seafood in Bangladesh.}, journal = {Heliyon}, volume = {10}, number = {20}, pages = {e39294}, pmid = {39640770}, issn = {2405-8440}, abstract = {Enterococcus faecalis are often resistant to different classes of antibiotics, harbor virulence determinants, and produce biofilm. The presence of E. faecalis in raw seafood exhibits serious public health significance. This study aimed to identify antibiotic resistance patterns and virulence factors in biofilm-forming E. faecalis strains extracted from seafood in Bangladesh. A total of 150 samples of raw seafood, comprising 50 shrimps, 25 crabs, and 75 fish, were collected and subjected to culturing, biochemical, and PCR assays to detect E. faecalis. The biofilm-forming abilities of the isolates were determined by Congo Red agar (CRA) plate and Crystal Violet Micro-titer Plate (CVMP) tests. Antibiotic resistance profiles were evaluated using the disk diffusion method. Virulence genes of the isolates were detected by PCR assay. The occurrence of E. faecalis was 29.3 % (44/150), which was higher in crabs and fish (36 %) than in shrimps (16 %). In CRA and CVMP tests, biofilm-forming abilities were observed in 88.64 % of the isolates, whereas 11 (25 %) and 28 (63.6 %) were strong- and intermediate-biofilm formers, respectively. All the isolates contained at least two virulence genes, including pil and ace (97.7 %), sprE (95.5 %), gelE (90.9 %), fsrB (79.6 %), agg (70.5 %), fsrA (68.2 %), and fsrC (61.4 %). All the isolates were phenotypically resistant to penicillin, followed by ampicillin and rifampicin (86.4 %), erythromycin (13.7 %), and tetracycline, vancomycin, norfloxacin, and linezolid (2.3 %). Resistant gene bla TEM was found in 61.4 % of the isolates. Moreover, the study found that E. faecalis strains with strong biofilm-forming capabilities had significantly higher levels of virulence genes and antibiotic resistance (p < 0.05) compared to those with intermediate and/or no biofilm-forming abilities. To the best of our knowledge, this research represents the first instance in Bangladesh of assessing antibiotic resistance and identifying virulence genes in biofilm-forming E. faecalis strains isolated from seafood samples. Our study revealed that seafood is a carrier of antibiotic-resistant, virulent, and biofilm-forming E. faecalis, demonstrating a potential public health threat.}, }
@article {pmid39640530, year = {2024}, author = {Zhang, Z and Chen, G and Hussain, W and Pan, Y and Yang, Z and Liu, Y and Li, E}, title = {Machine learning and network analysis with focus on the biofilm in Staphylococcus aureus.}, journal = {Computational and structural biotechnology journal}, volume = {23}, number = {}, pages = {4148-4160}, pmid = {39640530}, issn = {2001-0370}, abstract = {Research on biofilm formation in Staphylococcus aureus has greatly benefited from the generation of high-throughput sequencing data to drive molecular analysis. The accumulation of high-throughput sequencing data, particularly transcriptomic data, offers a unique opportunity to unearth the network and constituent genes involved in biofilm formation using machine learning strategies and co-expression analysis. Herein, the available RNA sequencing data related to Staphylococcus aureus biofilm studies and identified influenced functional pathways and corresponding genes in the process of the transition of bacteria from planktonic to biofilm state by employing machine learning and differential expression analysis. Using weighted gene co-expression analysis and previously developed online prediction platform, important functional modules, potential biofilm-associated proteins, and subnetworks of the biofilm-formation pathway were uncovered. Additionally, several novel protein interactions within these functional modules were identified by constructing a protein-protein interaction (PPI) network. To make this data more straightforward for experimental biologists, an online database named SAdb was developed (http://sadb.biownmcli.info/), which integrates gene annotations, transcriptomics, and proteomics data. Thus, the current study will be of interest to researchers in the field of bacteriology, particularly those studying biofilms, which play a crucial role in bacterial growth, pathogenicity, and drug resistance.}, }
@article {pmid39639551, year = {2024}, author = {Ma, Y and Kang, X and Wang, G and Luo, S and Luo, X and Wang, G}, title = {Inhibition of Staphylococcus aureus biofilm by quercetin combined with antibiotics.}, journal = {Biofouling}, volume = {40}, number = {10}, pages = {996-1011}, doi = {10.1080/08927014.2024.2435027}, pmid = {39639551}, issn = {1029-2454}, mesh = {*Biofilms/drug effects ; *Quercetin/pharmacology ; *Anti-Bacterial Agents/pharmacology ; *Staphylococcus aureus/drug effects/physiology ; *Microbial Sensitivity Tests ; *Tetracycline/pharmacology ; Drug Synergism ; Doxycycline/pharmacology ; Microscopy, Electron, Scanning ; }, abstract = {This study aimed to investigate the effects of combined quercetin and antibiotics on the bacteriostatic activity and biofilm formation of Staphylococcus aureus. Optimal concentrations of quercetin and antibiotics (tetracycline and doxycycline) for inhibiting biofilm formation were determined using the Fractional Inhibitory Concentration Index and Minimum Biofilm Inhibitory Concentration assays. The impact of the drug combinations on biofilm clearance at various formation stages was determined using crystal violet staining, scanning electron microscopy and confocal laser microscopy. The results indicated that quercetin enhanced the bactericidal effect of tetracycline antibiotics against S. aureus. The combination significantly reduced both the metabolic activity within S. aureus biofilms and the production of biofilm matrix components. Scanning electron microscopy and confocal laser microscopy confirmed that the combination treatment significantly reduced bacterial cell counts within the biofilm. Quercetin treatment significantly increased the sensitivity of biofilms to antibiotics, supporting its potential application as a novel antibiotic synergist.}, }
@article {pmid39639432, year = {2025}, author = {Sharifi, A and Mahmoudi, P and Sobhani, K and Ashengroph, M}, title = {The Prevalence and Comparative Analysis of Adhesion and Biofilm-Related Genes in Staphylococcus aureus Isolates: A Network Meta-Analysis.}, journal = {Microbiology and immunology}, volume = {69}, number = {2}, pages = {104-113}, doi = {10.1111/1348-0421.13189}, pmid = {39639432}, issn = {1348-0421}, support = {//The study was supported by University of Kurdistan, Iran./ ; }, mesh = {*Biofilms/growth &amp; development ; *Staphylococcus aureus/genetics/isolation &amp; purification/pathogenicity/physiology ; *Staphylococcal Infections/microbiology/epidemiology ; *Bacterial Adhesion/genetics ; Humans ; *Virulence Factors/genetics ; *Network Meta-Analysis as Topic ; Animals ; Adhesins, Bacterial/genetics ; Prevalence ; Bacterial Proteins/genetics ; }, abstract = {Staphylococcus aureus is a versatile pathogen capable of causing a wide range of infections, from minor skin infections to life-threatening invasive diseases. The pathogenicity of S. aureus is attributed to its ability to produce various virulence factors, including adhesion and biofilm-related proteins. Understanding the prevalence and distribution of these genes among S. aureus isolates from different sources is crucial for devising effective strategies to combat biofilm-associated contamination. In this study, we conducted a comprehensive network meta-analysis to assess the prevalence of adhesion and biofilm-related genes in S. aureus isolates and investigate the impact of the isolate source on their occurrence. A systematic search of multiple databases was performed, and a total of 53 relevant studies were included. The prevalence of adhesion and biofilm-related genes in S. aureus isolates was determined, with the highest prevalence observed for clfB (p-estimate = 85.4, 95% confidence interval [CI] 78-90.6), followed by eno (p-estimate = 81.1, 95% CI 61.7-91.9), and icaD (p-estimate = 77, 95% CI 68.6-83.6). Conversely, bap and bbp genes exhibited the lowest prevalence rates (p-estimate = 6.7 and 18.7, respectively). The network meta-analysis allowed us to examine the pairwise co-study of adhesion and biofilm-related genes in S. aureus isolates. The most frequently co-studied gene pairs were icaA-icaD (30 times) and fnbA-fnbB (25 times). Subgroup analysis showed that the occurrence of icaC and icaB genes was significantly lower in animal isolates compared to human and food isolates (p < 0.05). It is worth noting that there was limited data available for the analysis of sasG, bbp, bap, eno, and fib genes. In conclusion, the study revealed varying prevalence rates of adhesion and biofilm-related genes in S. aureus isolates. Genes such as clfB, eno, and icaD were found to be highly prevalent, while bap and bbp were less common. Limited existing data on the prevalence of genes like sasG, bbp, bap, eno, and fib highlights the need for further research to determine their exact prevalence rates. Our results contribute to a better understanding of S. aureus pathogenesis and can facilitate the development of effective strategies for the prevention and treatment of S. aureus infections.}, }
@article {pmid39638444, year = {2025}, author = {Zhao, J and Wang, D and Wang, C and Lin, Y and Ye, H and Maung, AT and El-Telbany, M and Masuda, Y and Honjoh, KI and Miyamoto, T and Xiao, F}, title = {Biocontrol of Salmonella Schwarzengrund and Escherichia coli O157:H7 planktonic and biofilm cells via combined treatment of polyvalent phage and sodium hexametaphosphate on foods and food contact surfaces.}, journal = {Food microbiology}, volume = {126}, number = {}, pages = {104680}, doi = {10.1016/j.fm.2024.104680}, pmid = {39638444}, issn = {1095-9998}, mesh = {*Biofilms/growth &amp; development/drug effects ; *Escherichia coli O157/growth &amp; development/physiology/virology ; *Food Microbiology ; *Salmonella/growth &amp; development/physiology/virology ; Food Contamination/prevention &amp; control/analysis ; Plankton/growth &amp; development/physiology ; Phosphates ; Colony Count, Microbial ; Triazines ; }, abstract = {Salmonella Schwarzengrund and Escherichia coli O157:H7 are ones of foodborne pathogens that can produce biofilms and cause serious food poisoning. Bacteriophages are an emerging antibacterial strategy used to prevent foodborne pathogen contamination in the food industry. In this study, the combined antibacterial effects of the polyvalent phage PS5 and sodium hexametaphosphate (SHMP) against both pathogens were investigated to evaluate their effectiveness in food applications. The combined treatment with phage PS5 (multiplicity of infection, MOI = 10) and 1.0% SHMP inhibited the growth of S. Schwarzengrund and E. coli O157:H7, and the viable counts of both decreased by more than 2.45 log CFU/mL. In KAGOME vegetable and fruit mixed juice, the combined treatment with PS5 (MOI = 100) and 1.0% SHMP also resulted in significant pathogen inactivation at 4 °C after 24 h. PS5 (10[10] PFU/mL) and 1.0% SHMP showed stronger synergistic effects on biofilm formation and the removal of established biofilms on polystyrene plates. Additionally, we evaluated their combined effects on reducing the biofilms of S. Schwarzengrund and E. coli O157:H7 on glass tubes and cabbage leaves at 4 °C. These findings indicate the utility of this approach in the biocontrol of the planktonic and biofilm cells of S. Schwarzengrund and E. coli O157:H7 on foods and food contact surfaces.}, }
@article {pmid39638047, year = {2025}, author = {Kanaujia, R and Sharma, A and Biswal, M and Singh, V}, title = {What doesn't kill biofilm, makes them stronger: critical methodological considerations for endoscope reprocessing.}, journal = {The Journal of hospital infection}, volume = {156}, number = {}, pages = {135-136}, doi = {10.1016/j.jhin.2024.06.024}, pmid = {39638047}, issn = {1532-2939}, }
@article {pmid39638004, year = {2025}, author = {Wang, ZJ and Yang, XL and Sun, Y and Song, HL}, title = {Selection and optimization of biofilm carriers as high-effective microbial separator in microbial fuel cells.}, journal = {Bioresource technology}, volume = {418}, number = {}, pages = {131941}, doi = {10.1016/j.biortech.2024.131941}, pmid = {39638004}, issn = {1873-2976}, mesh = {*Biofilms ; *Bioelectric Energy Sources/microbiology ; *Polyurethanes/chemistry ; Sulfides/chemistry ; Iron ; Biological Oxygen Demand Analysis ; Manganese ; Oxygen ; }, abstract = {Four biofilm carriers including pyrite, manganese ore, ceramsite, and polyurethane sponge were used to construct microbial separators (MSs), while their performance in dual-chamber microbial fuel cells (MFCs) was evaluated. Polyurethane sponge and pyrite were superior biofilm carriers for MSs. The dense biofilm on the polyurethane sponge provides MS with optimal barrier capacity against dissolved oxygen and chemical oxygen demand. Pyrite's unique redox activity enhances proton transfer in MS and reduces ohmic resistance in MFC. The optimal thicknesses of polyurethane sponge MS and pyrite MS were 1.20 and 1.80 cm, and the maximum power densities of MFCs equipped with these two MSs were 14.62 and 11.21 W/m[3]. Using MSs as separators can significantly lower MFC manufacturing costs, particularly with polyurethane sponge MS at 3.52 $/m[2]. Additionally, MSs demonstrated good regenerability. These results indicated that MSs based on pyrite and polyurethane sponge have the potential to be high-effective separators for MFC scale-up.}, }
@article {pmid39637855, year = {2024}, author = {Temme, JS and Tan, Z and Li, M and Yang, M and Wlodawer, A and Huang, X and Schneekloth, JS and Gildersleeve, JC}, title = {Insights into biofilm architecture and maturation enable improved clinical strategies for exopolysaccharide-targeting therapeutics.}, journal = {Cell chemical biology}, volume = {31}, number = {12}, pages = {2096-2111.e7}, doi = {10.1016/j.chembiol.2024.11.005}, pmid = {39637855}, issn = {2451-9448}, mesh = {*Biofilms/drug effects ; Animals ; *Polysaccharides, Bacterial/chemistry/metabolism ; Mice ; *Staphylococcus aureus/drug effects/physiology ; Antibodies, Monoclonal/pharmacology/chemistry ; Staphylococcal Infections/drug therapy/pathology ; Anti-Bacterial Agents/pharmacology/chemistry ; Humans ; Female ; Acetylation/drug effects ; Microbial Sensitivity Tests ; }, abstract = {Polysaccharide intercellular adhesin (PIA), an exopolysaccharide composed of poly-N-acetyl glucosamine (PNAG), is an essential component in many pathogenic biofilms. Partial deacetylation of PNAG is required for biofilm formation, but limited structural knowledge hinders therapeutic development. Employing a new monoclonal antibody (TG10) that selectively binds highly deacetylated PNAG and an antibody (F598) in clinical trials that binds highly acetylated PNAG, we demonstrate that PIA within the biofilm contains distinct regions of highly acetylated and deacetylated exopolysaccharide, contrary to the previous model invoking stochastic deacetylation throughout the biofilm. This discovery led us to hypothesize that targeting both forms of PNAG would enhance efficacy. Remarkably, TG10 and F598 synergistically increased in vitro and in vivo activity, providing 90% survival in a lethal Staphylococcus aureus challenge murine model. Our advanced model deepens the conceptual understanding of PIA architecture and maturation and reveals improved design strategies for PIA-targeting therapeutics, vaccines, and diagnostic agents.}, }
@article {pmid39636955, year = {2024}, author = {Timoncini, A and Lorenzetti, L and Turner, RJ and McGibbon, A and Martini, C and Cofini, E and Bernardi, E and Chiavari, C}, title = {Inhibition of Pseudomonas aeruginosa biofilm formation on copper-based thin foils.}, journal = {PloS one}, volume = {19}, number = {12}, pages = {e0314684}, pmid = {39636955}, issn = {1932-6203}, mesh = {*Pseudomonas aeruginosa/drug effects/physiology ; *Biofilms/drug effects/growth &amp; development ; *Copper/pharmacology/chemistry ; Humans ; Anti-Bacterial Agents/pharmacology/chemistry ; Surface Properties ; }, abstract = {The development of Healthcare-Associated Infections (HAIs) represents an increasing threat to patient health. In this context, Pseudomonas aeruginosa is responsible for various HAIs, determining about 20% of the infections in hospitalized patients, which makes it one of the most effective pathogens due to its strong ability to form biofilms. Using Cu-based materials as foils on high-touch surfaces can help to prevent and mitigate P. aeruginosa contamination in biohazardous settings. However, the antibiofilm properties of Cu-based surfaces against P. aeruginosa may vary due to frequent touches combined with indoor environmental exposure. The main aim of this study is to investigate the impact of accelerated ageing, mimicking a high-touch frequency by cyclic exposure to artificial sweat solution as well as to temperature and relative humidity variations, on the efficacy of Cu-based thin foils against P. aeruginosa biofilms. Three Cu-based materials (rolled and annealed Phosphorous High-Conductivity (PHC) Cu, Cu15Zn brass, and Cu18Ni20Zn nickel silver) were evaluated. The ageing process enhanced the antibiofilm properties, due to an increment in Cu ion release: aged PHC Cu and Cu15Zn exhibited the highest Cu ion release and hence the highest biofilm inhibition (decrease in colony forming unit (CFU)) in comparison to their pristine counterpart, while aged Cu18Ni20Zn displayed the lowest biofilm formation reduction, despite showing the highest aesthetic and morphological stability. The Cu-based surface, which highlited the highest biofilm formation inhibition due to accelerated ageing, was Cu15Zn.}, }
@article {pmid39636114, year = {2025}, author = {Cruz-Cruz, A and Schreeg, ME and Gunn, JS}, title = {A temporary cholesterol-rich diet and bacterial extracellular matrix factors favor Salmonella spp. biofilm formation in the cecum.}, journal = {mBio}, volume = {16}, number = {1}, pages = {e0324224}, pmid = {39636114}, issn = {2150-7511}, support = {R01 AI116917/AI/NIAID NIH HHS/United States ; R21 AI153752/AI/NIAID NIH HHS/United States ; AI153752//HHS | National Institutes of Health (NIH)/ ; AI116917//HHS | National Institutes of Health (NIH)/ ; }, mesh = {Animals ; *Cecum/microbiology ; *Biofilms/growth &amp; development ; Mice ; *Salmonella typhimurium/physiology/genetics/growth &amp; development ; *Feces/microbiology ; *Cholesterol/metabolism ; Extracellular Matrix/metabolism ; Disease Models, Animal ; Female ; Gallbladder/microbiology ; Carrier State/microbiology ; Diet ; }, abstract = {Asymptomatic chronic carriers occur in approximately 5% of humans infected with Salmonella enterica serovar Typhi (S. Typhi) and represent a critical reservoir for bacterial dissemination. While chronic carriage primarily occurs in the gallbladder (GB) through biofilms on gallstones, additional anatomic sites have been suggested that could also harbor Salmonella. S. Typhimurium, orally infected 129 × 1/SvJ mice were pre-treated with a cholesterol-rich diet as a gallstone model for chronic carriage. We observed S. Typhimurium in feces and the cecum during early and persistent infection. Furthermore, bacterial biofilm-like aggregates were associated with the cecum epithelium at 7 and 21 days post-infection (DPI) in mice on a lithogenic diet (Ld) and correlated with an increase in cecal cholesterol at 21 DPI. Salmonella's extracellular matrix (ECM) was demonstrated as important in colonizing the cecum, as survival and aggregate formation significantly decreased when mice were infected with a quadruple ECM mutant strain. Gallbladder Salmonella counts were low at 36 DPI while cecal Salmonella were high, suggesting that gallbladder colonization was likely not responsible for the high cecal burden. All cecum phenotypes were significantly diminished in mice fed a normal diet (Nd). Finally, we examined the capability of S. Typhi to colonize the cecum and showed S. Typhi in feces and in aggregates in the cecum up to 7 DPI, with slightly higher counts in mice fed a Ld compared to Nd. Our findings suggest that the cecum, particularly under cholesterol-rich conditions, serves as an adaptative niche for Salmonella spp. aggregates/biofilms and is a putative site for long-term infection.IMPORTANCETyphoid fever is a systemic infectious disease triggered by the gastrointestinal dissemination of Salmonella Typhi and Paratyphi in humans. Three to five percent of infected individuals become chronic carriers, a state in which gallstone biofilm formation facilitates spread of the bacteria in feces. Notably, surgical removal of the gallbladder (GB) in some chronic carriers (22%) does not guarantee the elimination of the bacteria, and the rationale for this remains poorly understood. This study is significant as it explores other tissues associated with the chronic carrier state. It highlights not only a cholesterol-rich diet as an important etiological factor for Salmonella colonization but also identifies the cecum as a crucial tissue promoting fecal shedding. Additionally, we determined that biofilm matrix components of Salmonella are key factors contributing to these effects. A greater understanding of these mechanisms will allow the formulation of new therapeutic strategies specifically targeted at preventing typhoid fever dissemination from chronic carriers.}, }
@article {pmid39635909, year = {2024}, author = {Zhao, Y and Zhang, J and Zhang, G and Huang, H and Tan, WS and Cai, H}, title = {Injectable Nanocomposite Hydrogel with Synergistic Biofilm Eradication and Enhanced Re-epithelialization for Accelerated Diabetic Wound Healing.}, journal = {ACS applied materials &amp; interfaces}, volume = {16}, number = {50}, pages = {69086-69102}, doi = {10.1021/acsami.4c17855}, pmid = {39635909}, issn = {1944-8252}, mesh = {*Biofilms/drug effects ; *Nanocomposites/chemistry/therapeutic use ; *Hydrogels/chemistry/pharmacology ; Animals ; *Wound Healing/drug effects ; Humans ; Methicillin-Resistant Staphylococcus aureus/drug effects ; Re-Epithelialization/drug effects ; Anti-Bacterial Agents/chemistry/pharmacology ; Mice ; Hyaluronic Acid/chemistry/pharmacology ; Cell Movement/drug effects ; Rats ; Human Umbilical Vein Endothelial Cells ; Male ; }, abstract = {Diabetic wounds remain a critical clinical challenge due to their harsh microenvironment, which impairs cellular function, hinders re-epithelialization and tissue remodeling, and slows healing. Injectable nanocomposite hydrogel dressings offer a promising strategy for diabetic wound repair. In this study, we developed an injectable nanocomposite hydrogel dressing (HDL@W379) using LAP@W379 nanoparticles and an injectable hyaluronic acid-based hydrogel (HA-ADH-ODEX). This dressing provided a sustained, pH-responsive release of W379 antimicrobial peptides, effectively regulating the wound microenvironment to enhance healing. The HDL@W379 hydrogel featured multifunctional properties, including mechanical stability, injectability, self-healing, biocompatibility, and tissue adhesion. In vitro, the HDL@W379 hydrogel achieved synergistic biofilm elimination and subsequent activation of basal cell migration and endothelial cell tube formation. Pathway analysis indicated that the HDL@W379 hydrogel enhances basal cell migration through MEK/ERK pathway activation. In methicillin-resistant Staphylococcus aureus (MRSA)-infected diabetic wounds, the HDL@W379 hydrogel accelerated wound healing by inhibiting bacterial proliferation and promoting re-epithelialization, regenerating the granulation tissue, enhancing collagen deposition, and facilitating angiogenesis. Overall, this strategy of biofilm elimination and basal cell activation to continuously regulate the diabetic wound microenvironment offers an innovative approach to treating chronic wounds.}, }
@article {pmid39634881, year = {2024}, author = {Mumtaz, A and Saleem, U and Arif, M and Batool, N}, title = {Investigation of antibiotic resistance and biofilm formation ability of Acinetobacter baumannii isolated from urinary catheters.}, journal = {Pakistan journal of medical sciences}, volume = {40}, number = {11}, pages = {2643-2647}, pmid = {39634881}, issn = {1682-024X}, abstract = {OBJECTIVE: Current research aims to monitor the prevalence of Acinetobacter baumannii (A. baumannii) in healthcare facilities due to the development of resistance to antimicrobials. The study aimed to elucidate the interplay between antibiotic resistance and biofilm formation, two key factors contributing to virulence of bacteria.<br><br>METHODS: This study was conducted in One Health Laboratory (OHL) at Center for Advanced Studies, Agriculture and Food Security (CAS AFS), and institute of Microbiology University of Agriculture, Faisalabad within six months (Feb-Aug 2023). A total of 50 urine catheter samples were obtained from Allied Hospital, Faisalabad. Antibiotic susceptibility testing (meropenem, ampicillin, ceftriaxone, and gentamicin) was conducted to determine the resistance profiles of the isolates in accordance with the Clinical and Laboratory Standards Institute (CLSI) guidelines. Additionally, the biofilm formation ability of the isolates was assessed using crystal violet staining.<br><br>RESULTS: Out of 50 samples, 13 were positive and were confirmed as multidrug resistant. The investigation of antibiotic resistance revealed a high prevalence of MDR A. baumannii strains from urinary catheters. The rate of infection was observed higher in males (77%), patients among the age group 10-25 and above 46 years (38.46%), and those who have been diagnosed with urinary tract infection (46.13%). The observed rate of biofilm formation was strong (62%) followed by moderate (7%), and weak (31%) in all MDR isolates. Carbapenem-resistant isolates exhibit a strong correlation with biofilm formation.<br><br>CONCLUSION: This study concluded that A. baumannii isolated from the patients with urinary tract infections had resistance to routinely used antibiotics. The isolates have shown hemolysis pattern (&#x3b1; &amp; &#x3b3;) and tendency to make biofilms. Moreover, except for ceftriaxone which showed negative correlations, a positive correlation was observed between biofilm biomass and the resistance profile to the remaining three antibiotics.}, }
@article {pmid39634722, year = {2024}, author = {Mitra, A}, title = {Combatting biofilm-mediated infections in clinical settings by targeting quorum sensing.}, journal = {Cell surface (Amsterdam, Netherlands)}, volume = {12}, number = {}, pages = {100133}, pmid = {39634722}, issn = {2468-2330}, abstract = {Biofilm-associated infections constitute a significant challenge in managing infectious diseases due to their high resistance to antibiotics and host immune responses. Biofilms are responsible for various infections, including urinary tract infections, cystic fibrosis, dental plaque, bone infections, and chronic wounds. Quorum sensing (QS) is a process of cell-to-cell communication that bacteria use to coordinate gene expression in response to cell density, which is crucial for biofilm formation and maintenance.. Its disruption has been proposed as a potential strategy to prevent or treat biofilm-associated infections leading to improved treatment outcomes for infectious diseases. This review article aims to provide a comprehensive overview of the literature on QS-mediated disruption of biofilms for treating infectious diseases. It will discuss the mechanisms of QS disruption and the various approaches that have been developed to disrupt QS in reference to multiple clinical pathogens. In particular, numerous studies have demonstrated the efficacy of QS disruption in reducing biofilm formation in various pathogens, including Pseudomonas aeruginosa and Staphylococcus aureus. Finally, the review will discuss the challenges and future directions for developing QS disruption as a clinical therapy for biofilm-associated infections. This includes the development of effective delivery systems and the identification of suitable targets for QS disruption. Overall, the literature suggests that QS disruption is a promising alternative to traditional antibiotic treatment for biofilm-associated infections and warrants further investigation.}, }
@article {pmid39634676, year = {2024}, author = {Bello, OO and Oni, MO and Bello, TK and Ilemobayo, AM and Ajagunna, AM and Osho, A}, title = {Biofilm-Forming Antibiotic-Resistant Bacteria in Water From Distribution Systems: Occurrence and Public Health Implications.}, journal = {International journal of microbiology}, volume = {2024}, number = {}, pages = {4147226}, pmid = {39634676}, issn = {1687-918X}, abstract = {Biofilm is a structurally-connected microbial community, covered by a self-produced polymeric matrix and adhered to biotic or abiotic surfaces. This study aimed to evaluate the occurrence of biofilm-producing antibiotic-resistant bacteria in water from distribution systems. Water samples were taken from 32 tanks across Ondo City and Akure metropolis, Nigeria. Information regarding the sanitation status of the tanks was gathered by observation and oral interviews. The physicochemical properties were determined using standard methods. Using the pour plate technique. Agars included serially diluted water samples were inoculated onto plate count agar, mannitol salt agar, Salmonella-Shigella agar, MacConkey agar, and cetrimide nutrient agar to assess total viable bacteria, Staphylococcus aureus, Salmonella and Shigella, coliforms, and Pseudomonas aeruginosa, respectively. Eosin-methylene blue agar was used to cultivate Escherichia coli and Enterobacter aerogenes. Pure isolates were characterised using API kits and assessed for antibiotic resistance and biofilm production employing the Kirby-Bauer and tissue culture plate techniques, respectively. The ages of the water tanks ranged from 1 to 25 years old; all tanks had cover-lids; 13 (40.63%) had water guards while 12 (37.5%) underwent water treatment. The physicochemical properties chiefly fell within WHO standards for drinking water. One hundred and eighty-seven isolates were obtained. S. aureus (15.51%) had the highest frequency while Salmonella enterica (3.2%) had the lowest frequency. Thirty-six percent of the isolates were strong biofilm producers, while 20.67% Gram-negative and 18.69% Gram-positive bacterial isolates were antibiotic-resistant. This study revealed a high occurrence of biofilm-forming bacteria and prevalence of antibiotic-resistant bacteria in water distribution systems, emphasizing the urgency of improving water quality for public health protection.}, }
@article {pmid39634280, year = {2024}, author = {Xie, J and Sun, X and Xia, Y and Tao, L and Tan, T and Zhang, N and Xun, W and Zhang, R and Kovács, &#xc1;T and Xu, Z and Shen, Q}, title = {Bridging the Gap: Biofilm-mediated establishment of Bacillus velezensis on Trichoderma guizhouense mycelia.}, journal = {Biofilm}, volume = {8}, number = {}, pages = {100239}, pmid = {39634280}, issn = {2590-2075}, abstract = {Bacterial-fungal interactions (BFIs) are important in ecosystem dynamics, especially within the soil rhizosphere. The bacterium Bacillus velezensis SQR9 and the fungus Trichoderma guizhouense NJAU 4742 have gathered considerable attention due to their roles in promoting plant growth and protecting their host against pathogens. In this study, we utilized these two model microorganisms to investigate BFIs. We firstly demonstrate that while co-inoculation of B. velezensis and T. guizhouense could promote tomato growth, these two microorganisms display mutual antagonism on agar solidified medium. To resolve this contradiction, we developed an inoculation method, that allows B. velezensis colonization of T. guizhouense hyphae and performed a transcriptome analysis. During colonization of the fungal hyphae, B. velezensis SQR9 upregulates expression of biofilm related genes (e.g. eps, tasA, and bslA) that is distinct from free-living cells. This result suggested an intricate association between extracellular matrix expression and hyphae colonization. In accordance, deletion epsD, tasA, or both epsD and tasA genes of B. velezensis diminished colonization of the T. guizhouense hyphae. The insights from our study demonstrate that soil BFIs are more complex than we understood, potentially involving both competition and cooperation. These intricate biofilm-mediated BFI dynamics might contribute to the remarkable diversity observed within soil microbiota, providing a fresh perspective for further exploration of BFIs in the plant rhizosphere.}, }
@article {pmid39633500, year = {2024}, author = {Sandbakken, ET and Høyer, E and Witsø, E and Søgaard, CK and Díez-Sánchez, A and Hoang, L and Wik, TS and Bergh, K}, title = {Biofilm and the effect of sonication in a chronic Staphylococcus epidermidis orthopedic in vivo implant infection model.}, journal = {Journal of orthopaedic surgery and research}, volume = {19}, number = {1}, pages = {820}, pmid = {39633500}, issn = {1749-799X}, mesh = {*Biofilms/growth &amp; development ; *Staphylococcus epidermidis ; Animals ; *Rats, Wistar ; *Prosthesis-Related Infections/microbiology ; *Sonication/methods ; *Staphylococcal Infections/microbiology ; *Disease Models, Animal ; Rats ; Chronic Disease ; Male ; Bone Plates ; }, abstract = {BACKGROUND: In diagnosing chronic orthopedic implant infections culture of sonicate represents a supplement to tissue cultures. However, the extent to which biofilm forms on implant surfaces and the degree of dislodgement of bacteria by sonication remains unclear. In this in vivo study using a low bacterial inoculum, we aimed to determine whether a variable effect of sonication could be observed in a standardized in vivo model.<br><br>MATERIALS AND METHODS: Seven Wistar rats underwent surgery with intramuscular implantation of two bone xenograft implants, each containing two steel plates. The grafts were inoculated with approximately 500 colony forming units (CFU) of Staphylococcus epidermidis ATCC 35984. After 20 days the rats were sacrificed, and the steel plates were removed from the bone grafts. Epifluorescence microscopy and scanning electron microscopy (SEM) were used to visualize biofilm formation and dislodgement on the plate surfaces. In addition to cultures of sonicate, a quantitative S. epidermidis specific PCR was developed for enumeration of bacteria.<br><br>RESULTS: A chronic, low-grade implant infection was successfully established, with all animals remaining in good health. All infected bone graft implants yielded abundant growth of S. epidermidis, with a median of 3.25 (1.6-4.6)&#x2009;&#xd7;&#x2009;10&#x2077; CFU per/graft. We were unable to distinguish infected plates from negative controls using epifluorescence microscopy. On infected plates small colonies of staphylococci were identified by SEM. The number of bacteria detected in the sonicate was low with 500 (100-2400) CFU/plate and 475 (140-1821) copies/plate by qPCR. The difference in area covered by fluorescent material before and after sonication was 10.1 (5.7-12.3) %, p&#x2009;=&#x2009;0.018.<br><br>CONCLUSION: Despite the pronounced infection in the surrounding tissue, only few bacteria were detected on the surface of the steel implants. This is evident from the minimal findings by SEM before sonication, as well as the very low CFU counts and DNA copies in the sonicate. Sonication did not show variable effectiveness, indicating it is a valuable addition to, but not a replacement for biopsy cultures in cases of implant-associated infections with low-virulence microorganisms.}, }
@article {pmid39633147, year = {2024}, author = {Farias-da-Silva, FF and Benine-Warlet, J and Groppo, FC and Steiner-Oliveira, C}, title = {Potentiation of antimicrobial photodynamic therapy with potassium iodide and methylene blue: targeting oral biofilm viability.}, journal = {Photochemical &amp; photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology}, volume = {23}, number = {12}, pages = {2255-2263}, pmid = {39633147}, issn = {1474-9092}, support = {88887.512822/2020-00//Coordena&#xe7;&#xe3;o de Aperfei&#xe7;oamento de Pessoal de N&#xed;vel Superior/ ; Finance code 001//Coordena&#xe7;&#xe3;o de Aperfei&#xe7;oamento de Pessoal de N&#xed;vel Superior/ ; }, mesh = {*Biofilms/drug effects ; *Methylene Blue/pharmacology/chemistry ; *Potassium Iodide/pharmacology/chemistry ; *Photochemotherapy ; Humans ; *Photosensitizing Agents/pharmacology/chemistry ; Animals ; Cattle ; Adult ; Female ; Male ; Streptococcus mutans/drug effects/physiology ; Microbial Viability/drug effects ; Young Adult ; Anti-Bacterial Agents/pharmacology/chemistry ; }, abstract = {The study aimed to assess the impact of combining potassium iodide (KI) with methylene blue (MB) in antimicrobial photodynamic therapy (aPDT) within an oral biofilm formed in situ. A single-phase, 14 days in situ study involved 21 volunteers, who wore a palatal appliance with 8 bovine dentin slabs. These slabs were exposed to a 20% sucrose solution 8 times a day, simulating a high cariogenic challenge. Following the intraoral phase, the biofilms formed on the slabs were randomly assigned to the treatments: C (0.9% NaCl); CHX (0.2% chlorhexidine); KI (75 mM KI); MBKI (0.005% MB + 75 mM KI); L (0.9% NaCl + red laser 660 nm, 18 J, 180 s); LMB (0.005% MB + laser); LKI (75 mM KI + laser); LMBKI (0.005% MB + 75 mM KI + laser). The treated biofilms were collected, diluted, and incubated to assess cell viability (CFU/mL) for total microorganisms, total lactobacilli, total streptococci, and mutans streptococci. Data were subjected to analysis using the Friedman test, followed by the Dunn test (α = 0.05). LMBKI group exhibited a noteworthy decrease in the viability of all microorganisms in comparison to groups C, KI, MBKI, MB, L, LMB, and LKI (p < 0.0001), and demonstrated a comparable reduction to the CHX group (p > 0.99). The combination of KI with MB in aPDT may be advocated as a non-invasive technique for diminishing the viability of polymicrobial oral biofilms, thereby aiding in the management of dental diseases.}, }
@article {pmid39633009, year = {2024}, author = {Park, S and Lee, ES and Kim, A and Kim, HJ and Lee, JY and Kim, SK and Jung, HI and Kim, BI}, title = {Development of a novel tongue biofilm index using bacterial biofluorescence.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {30196}, pmid = {39633009}, issn = {2045-2322}, mesh = {Humans ; *Biofilms/growth &amp; development ; *Tongue/microbiology ; Male ; Female ; Aged ; *Hydrogen Sulfide/metabolism/analysis ; Aged, 80 and over ; Sulfhydryl Compounds/metabolism ; Fluorescence ; Reproducibility of Results ; Bacteria/metabolism ; }, abstract = {Conventional methods for assessing tongue bacterial biofilms have low inter-examiner reliability due to visualization challenges. This study aimed to develop and assess a novel Tongue Biofilm Fluorescence Index (TBFI) for the accurate detection and objective evaluation of the quantitative and qualitative characteristics of tongue biofilms at the chairside. Data were collected from 81 elderly individuals (n = 162 images). Qraycam captured white-light and fluorescence images of the dorsal tongue, and two examiners assessed tongue coating (TC) using the TBFI. The TBFI was calculated based on biofilm intensity and coverage (0-2 scale). Inter-examiner agreement (Kappa) was compared with the Winkel's Tongue Coating Index (WTCI) and the Oho Index. Validity was evaluated through correlations with hydrogen sulfide (H2S) and methyl mercaptan (CH3SH) levels. TBFI demonstrated the highest inter-examiner reliability (TBFI, κ = 0.752; WTCI, κ = 0.317; Oho Index, κ = 0.496), particularly for thickness rating (agreement rate: TBFI, 96.3%; WTCI, 76.5%; Oho Index, 79.6%). H2S and CH3SH concentrations showed significant positive correlations with all three indices, with the highest correlation observed between H2S and TBFI (TBFI, r = 0.369; WTCI, r = 0.304; Oho Index, r = 0.308; p < 0.01). Furthermore, H2S levels increased significantly with higher TBFI scores (p < 0.0001). TBFI shows enhanced reliability and validity, supporting its clinical potential.}, }
@article {pmid39632887, year = {2024}, author = {Siri, M and Vázquez-Dávila, M and Sotelo Guzman, C and Bidan, CM}, title = {Nutrient availability influences E. coli biofilm properties and the structure of purified curli amyloid fibers.}, journal = {NPJ biofilms and microbiomes}, volume = {10}, number = {1}, pages = {143}, pmid = {39632887}, issn = {2055-5008}, mesh = {*Biofilms/growth &amp; development ; *Escherichia coli/physiology ; *Amyloid/metabolism/chemistry ; *Bacterial Proteins/metabolism/genetics ; *Nutrients/metabolism ; Escherichia coli Proteins/metabolism ; }, abstract = {Bacterial biofilms are highly adaptable and resilient to challenges. Nutrient availability can induce changes in biofilm growth, architecture and mechanical properties. Their extracellular matrix plays an important role in achieving biofilm stability under different environmental conditions. Curli amyloid fibers are critical for the architecture and stiffness of E. coli biofilms, but how this major matrix component adapts to different environmental cues remains unclear. We investigated, for the first time, the effect of nutrient availability both on biofilm material properties and on the structure and properties of curli amyloid fibers extracted from similar biofilms. Our results show that biofilms grown on low nutrient substrates are stiffer, contain more curli fibers, and these fibers present higher β-sheet content and chemical stability. Our multiscale study sheds new light on the relationship between bacterial matrix molecular structure and biofilm macroscopic properties. This knowledge will benefit the development of both anti-biofilm strategies and biofilm-based materials.}, }
@article {pmid39631547, year = {2025}, author = {Ni, J and Hu, Y and Liang, D and Cheng, J and Chen, Y and Zhu, X and Wang, G and Xie, J}, title = {Performance and mechanisms of nitrogen removal from low-carbon source wastewater in an iron-carbon coupled biofilm airlift internal circulation sequencing batch reactor.}, journal = {Bioresource technology}, volume = {418}, number = {}, pages = {131925}, doi = {10.1016/j.biortech.2024.131925}, pmid = {39631547}, issn = {1873-2976}, mesh = {*Nitrogen/metabolism ; *Carbon/metabolism ; *Bioreactors/microbiology ; *Biofilms ; *Iron/metabolism ; *Wastewater/chemistry ; Water Purification/methods ; Waste Disposal, Fluid/methods ; Extracellular Polymeric Substance Matrix/metabolism ; Bacteria/metabolism ; }, abstract = {An iron-carbon coupled biofilm airlift internal circulation sequencing batch reactor (IC-SBR) was constructed to treat low-carbon source wastewater. Single-factor experiments were used to determine the optimal operating conditions for the IC-SBR, with a hydraulic retention time (HRT) of 10 h, a dissolved oxygen (DO) concentration of 3 mg/L, a C/N ratio of 3, and an influent NH4[+]-N concentration of 50 mg/L, with average removal efficiencies of total nitrogen (TN) and total organic carbon (TOC) of 78.06% and 97.15%, respectively. Mechanistic studies of the IC-SBR indicated that iron-carbon selectively enriched nitrogen removal microorganisms and promoted nitrogen removal efficiency. Carbon sources affected the secretion of extracellular polymeric substances (EPS), enzyme activities, electron transport system activity, nitrogen removal gene abundance, and community structure of microorganisms in the IC-SBR. Microorganisms use EPS as a supplementary carbon source to ensure nitrogen removal efficiency when the carbon source is insufficient.}, }
@article {pmid39631356, year = {2025}, author = {Xia, W and Cai, Q and Wu, H and Li, J and Zhou, Z and Huang, C and Cheng, B}, title = {Improve anti-biofilm efficacy of ultrasound by modulating the phase transition of exopolysaccharides.}, journal = {Ultrasonics sonochemistry}, volume = {112}, number = {}, pages = {107100}, pmid = {39631356}, issn = {1873-2828}, mesh = {*Biofilms/drug effects ; *Polysaccharides, Bacterial/pharmacology/chemistry ; *Staphylococcus aureus/drug effects ; *Phase Transition ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Ultrasonic Waves ; Chitosan/pharmacology/chemistry ; }, abstract = {This study focused on the adverse sonochemical effect of ultrasound on biofilm extracellular polysaccharide and the adaptive biofilm responses for ultrasound resistance. Results showed ultrasound triggered phase transition of polysaccharides within biofilm from solation to gelation, which induced following biofilm viscoelasticity enhancement, consequential failure of biofilm removal and bacteria killing. Introducing additional cationic polysaccharide, 1.25 % chitosan, inhibited the ultrasound responsive polysaccharides gelation and biofilm viscoelasticity enhancement, exerted synergistic antibacterial (97.40 %) and antibiofilm (96.38 %) effects with 120 W ultrasound combined on S. aureus biofilm, prolonged the preservation time of milk 2.45 times longer compared with ultrasound alone. These findings indicated the possible mechanism and solution to improve ultrasound efficacy on biofilm control and bacteria suppression, exhibit the promising prospect of ultrasound combined strategy in hygiene issues of food and medical industry.}, }
@article {pmid39630533, year = {2024}, author = {Mitsuwan, W and Saengsawang, P and Thaikoed, S and Tanthanathipchai, N and Saedan, P and Chaisiri, K and Boonmar, S and Morita, Y}, title = {Rattus spp. as Reservoirs of Multidrug Resistance- and Biofilm-Forming Escherichia coli in Urban Community from Southern Thailand.}, journal = {Foodborne pathogens and disease}, volume = {}, number = {}, pages = {}, doi = {10.1089/fpd.2024.0109}, pmid = {39630533}, issn = {1556-7125}, abstract = {Rats are rodents commonly found in Thailand that carry various zoonotic pathogens. Bacterial zoonosis can occur in a shared environment between humans and rats, especially in human communities and agricultural areas. Escherichia coli, particularly pathogenic and multidrug-resistant strains, is a significant public health concern that is transmitted by rats. This study aimed to investigate the antibiotic resistance (ABR) and biofilm formation of E. coli in caught rodents from Nakhon Si Thammarat province, Thailand. Captured rats were dissected to collect intestinal content for E. coli isolation. Two hundred and two confirmed E. coli were subjected for pathotype identification, antibiotic susceptibility testing, biofilm-forming ability (BFA), and the presence of related genes. Two E. coli isolates from intestinal content samples were atypical enteropathogenic (aEPEC). Predominantly, 52.97% of E. coli had azithromycin resistance, which was harbored by 35.64% of captured rats. Multidrug resistance (MDR) was found in 12.38% of E. coli isolates with 17 different MDR patterns. Remarkably, 96% of MDR isolates were resistant to azithromycin. Most E. coli harbored ereA (52%), followed by the blaTEM and aacC2 genes (6.44% each). Approximately 87% of isolated E. coli revealed moderate-to-high BFA. Predominantly, moderate-to-strong biofilm-forming E. coli harbored pgaA and pgaC genes. aEPEC, azithromycin resistance, MDR, and moderate-to-strong formation were the aspects of concern. Furthermore, the study of antibiotic-resistant E. coli in rats should be performed, particularly in terms of the transmission pathway, and the application of rats as bioindicators for ABR surveillance in Thailand should be established.}, }
@article {pmid39629932, year = {2025}, author = {Doll-Nikutta, K and Weber, SC and Mikolai, C and Denis, H and Behrens, W and Szafrański, SP and Ehlert, N and Stiesch, M}, title = {Gradual Acidification at the Oral Biofilm-Implant Material Interface.}, journal = {Journal of dental research}, volume = {104}, number = {2}, pages = {164-171}, doi = {10.1177/00220345241290147}, pmid = {39629932}, issn = {1544-0591}, mesh = {*Biofilms/growth &amp; development ; Hydrogen-Ion Concentration ; *Dental Implants/microbiology ; *Microscopy, Confocal ; *Streptococcus oralis/physiology ; Humans ; *Titanium/chemistry ; *Surface Properties ; }, abstract = {The colonization of dental implants by oral biofilms causes inflammatory reactions that can ultimately lead to implant loss. Therefore, safety-integrated implant surfaces are under development that aim to detect bacterial attachment at an early stage and subsequently release antibacterial compounds to prevent their accumulation. Since primary oral colonizers ferment carbohydrates leading to local acidification, pH is considered a promising trigger for these surfaces. As a prerequisite for such systems, the present study aimed at specifically analyzing the pH at the interface between implant material and oral biofilms. For this purpose, in vitro-grown Streptococcus oralis monospecies biofilms and an established multispecies biofilm on titanium discs as well as in situ-grown biofilms from orally exposed titanium-equipped splints were used. Mature biofilm morphology was characterized by live/dead fluorescence staining, revealing improved growth from in vitro to in situ biofilms as well as a general decreasing membrane permeability over time due to the static incubation conditions. For pH analysis, the pH-sensitive dye C-SNARF-4 combined with 3-dimensional imaging by confocal laser-scanning microscopy and digital image analysis were used to detect extracellular pH values in different biofilm layers. All mature biofilms showed a pH gradient, with the lowest values at the material interface. Interestingly, the exact values depicted a time- and nutrient-dependent gradual acidification independently of the biofilm source and for in situ biofilms also independently of the sample donor. After short incubation times, a mild acidification to approximately pH 6.3 could be observed. But when sufficient nutrients were processed for a longer period of time, acidification intensified, leading to approximately pH 5.0. This not only defines the required turning point of pH-triggered implant release systems but also reveals the opportunity for a tailored release at different stages of biofilm formation.}, }
@article {pmid39629160, year = {2024}, author = {Rachmawati, E and Asarina, S and Bagus Kennardi, G and Tabina Tawangalun, A and Arumimaniyah, C and Indah Sari, K and Tjaturina Pramesti, H and Safitri, R and Maskoen, AM}, title = {Isolation of Thermophilic Bacteria Geobacillus subterraneus From Mount Tangkuban Perahu and the Novelty as a Candidate for Streptococcus mutans Anti-Biofilm.}, journal = {International journal of dentistry}, volume = {2024}, number = {}, pages = {4285984}, pmid = {39629160}, issn = {1687-8728}, abstract = {Thermophilic bacteria living in extreme areas with high temperatures are capable of producing secondary metabolites, such as antimicrobial peptides (AMPs). AMPs are stable at high temperatures and show good antibacterial activity. Therefore, this study aimed to identify thermophilic bacteria from the crater of Mount Tangkuban Perahu around West Java and assess antibacterial effectiveness of AMPs against Streptococcus mutans, which contribute to oral biofilm formation. The isolate obtained was identified using 16S ribosomal ribonucleic acid (rRNA) gene sequencing, and the supernatant of the isolate was tested against S. mutans American Type Culture Collection (ATCC) 25175 using the disc assay method. To determine AMPs-coding genes, its genome was uploaded to antibiotic and secondary metabolite analysis shell (antiSMASH) 5.0.0 platform and biofilm inhibition was tested using the microtiter plate technique (with a 96-well bottom). Subsequently, the results were assessed using a microplate reader operating at 595 nm wavelength. The isolate was identified as Geobacillus subterraneus, with antibacterial activity against S. mutans, and produced an inhibition zone of 8.40 mm at an optimum pH of 8. The output of AMPs-coding gene showed that AMPs of the isolate were a member of the lanthipeptide class I, or bacteriocin-I group. AMPs of G. subterraneus suppressed the growth of S. mutans biofilm at a supernatant concentration of 5%, with the lowest optical density (OD) value of 0.061 and the highest percentage of biofilm growth inhibition at 28.24%. Based on the results, G. subterraneus derived from the crater of Mount Tangkuban Perahu showed potent antibacterial properties against S. mutans, making it a promising novel S. mutans anti-biofilm candidate.}, }
@article {pmid39628792, year = {2024}, author = {Wu, X and Wang, C and Wang, D and Tawfik, A and Xu, R and Yu, Z and Meng, F}, title = {Achieving simultaneous removal of carbon and nitrogen by an integrated process of anaerobic membrane bioreactor and flow-through biofilm reactor.}, journal = {Engineering microbiology}, volume = {4}, number = {1}, pages = {100136}, pmid = {39628792}, issn = {2667-3703}, abstract = {In this study, a combined system consisting of an anaerobic membrane bioreactor (AnMBR) and flow-through biofilm reactor/CANON (FTBR/CANON) was developed to simultaneously remove carbon and nitrogen from synthetic livestock wastewater. The average removal efficiencies of total nitrogen (TN) were 64.2 and 76.4% with influent ammonium (NH4 [+]-N) concentrations of approximately 200 and 500 mg/L, respectively. The COD removal efficiencies were higher than 98.0% during the entire operation. Mass balance analysis showed that COD and TN were mainly removed by the AnMBR and FTBR/CANON, respectively. The anammox process was the main nitrogen removal pathway in the combined system, with a contribution of over 80%. High functional bacterial activity was observed in the combined system. Particularly, an increase in the NH4 [+]-N concentration considerably improved the anammox activity of the biofilm in the FTBR/CANON. 16S rRNA high-throughput sequencing revealed that Methanosaeta, Candidatus Methanofastidiosum, and Methanobacterium were the dominant methanogens in the AnMBR granular sludge. In the CANON biofilm, Nitrosomonas and Candidatus Kuenenia were identified as aerobic and anaerobic ammonium-oxidizing bacteria, respectively. In summary, this study proposes a combined AnMBR and FTBR/CANON process targeting COD and nitrogen removal, and provides a potential alternative for treating high-strength wastewater.}, }
@article {pmid39626168, year = {2025}, author = {Abbott, IJ and Anderson, CRB and van Gorp, E and Wallis, SC and Roberts, JA and Meletiadis, J and Peleg, AY}, title = {Oral ciprofloxacin biofilm activity in a catheter-associated urinary tract infection model.}, journal = {The Journal of antimicrobial chemotherapy}, volume = {80}, number = {2}, pages = {413-426}, pmid = {39626168}, issn = {1460-2091}, support = {//Australian Society for Antimicrobial/ ; APP1117065//Australian National Health and Medical Research Council/ ; //Australian/ ; APP2007007//for a Centre of Research Excellence/ ; APP2009736//Investigator Grant/ ; //Advancing Queensland Clinical Fellowship/ ; }, mesh = {*Ciprofloxacin/pharmacology ; *Biofilms/drug effects/growth &amp; development ; *Urinary Tract Infections/microbiology ; Humans ; *Microbial Sensitivity Tests ; *Catheter-Related Infections/microbiology/drug therapy ; *Anti-Bacterial Agents/pharmacology ; *Pseudomonas aeruginosa/drug effects/physiology ; *Klebsiella pneumoniae/drug effects/physiology ; Escherichia coli/drug effects/isolation &amp; purification/physiology ; Administration, Oral ; }, abstract = {BACKGROUND: Catheter-associated urinary tract infections (CA-UTIs) are a common hospital-acquired infection. We examined ciprofloxacin activity in a novel CA-UTI in vitro model.<br><br>METHODS: Three ATCC strains [Escherichia coli (ECO)-25922, Klebsiella pneumoniae (KPN)-700721, Pseudomonas aeruginosa (PAE)-27853] and 45 clinical urinary isolates were assessed. Biofilm mass and planktonic bacterial density were quantified during drug-free incubation (72&#x2005;h) and following ciprofloxacin exposure (equivalent 750&#x2005;mg orally q12h, 3&#x2005;days).<br><br>RESULTS: ECO produced smaller biofilms (6.3&#x200a;&#xb1;&#x200a;1.1&#x2005;log10&#x2005;cfu/cm2) compared with KPN (7.1&#x200a;&#xb1;&#x200a;0.7&#x2005;log10&#x2005;cfu/cm2) and PAE (7.0&#x200a;&#xb1;&#x200a;1.2&#x2005;log10&#x2005;cfu/cm2), which extended along the entire catheter length. Following ciprofloxacin, all isolates with MIC&#x200a;>&#x200a;4&#x2005;mg/L had minimal biofilm disruption or planktonic kill. Ciprofloxacin resistance was most common in PAE isolates (10/16 isolates), compared with ECO (3/16 isolates) and KPN (6/16 isolates). Greater ciprofloxacin exposure (AUC0-24/MIC) was required for a 3&#x2005;log10 biofilm kill for KPN (5858; R2&#x2005;=&#x2005;0.7774) compared with ECO (2117; R2&#x2005;=&#x2005;0.7907) and PAE (2485; R2&#x2005;=&#x2005;0.8260). Due to persistent growth in the bladder, ECO required greater ciprofloxacin exposure for a 3&#x2005;log10 planktonic kill (5920; R2&#x2005;=&#x2005;0.8440) compared with KPN (2825; R2&#x2005;=&#x2005;0.9121) and PAE (1760; R2&#x2005;=&#x2005;0.8781). Monte Carlo simulation supported a 95% PTA for both a 3&#x2005;log10 biofilm and planktonic kill for ECO and KPN isolates with MIC&#x200a;&#x2264;&#x200a;0.5&#x2005;mg/L and PAE isolates with MIC&#x200a;&#x2264;&#x200a;1&#x2005;mg/L.<br><br>CONCLUSIONS: In a novel CA-UTI model, following simulated ciprofloxacin therapy, KPN biofilms were comparatively more difficult to disrupt, ECO planktonic growth frequently persisted in the bladder, and PAE had greater propensity for emergence of ciprofloxacin resistance.}, }
@article {pmid39625293, year = {2025}, author = {Zhao, D and Tang, M and Hu, P and Hu, X and Chen, W and Ma, Z and Chen, H and Liu, H and Cao, J and Zhou, T}, title = {Antimicrobial peptide Hs02 with rapid bactericidal, anti-biofilm, and anti-inflammatory activity against carbapenem-resistant Klebsiella pneumoniae and Escherichia coli.}, journal = {Microbiology spectrum}, volume = {13}, number = {1}, pages = {e0105024}, pmid = {39625293}, issn = {2165-0497}, mesh = {*Biofilms/drug effects ; *Klebsiella pneumoniae/drug effects ; Animals ; Mice ; *Escherichia coli/drug effects ; *Anti-Inflammatory Agents/pharmacology ; *Anti-Bacterial Agents/pharmacology/chemistry ; RAW 264.7 Cells ; *Microbial Sensitivity Tests ; *Antimicrobial Peptides/pharmacology/chemistry ; *Carbapenems/pharmacology ; Lipopolysaccharides/metabolism/pharmacology ; Klebsiella Infections/microbiology/drug therapy ; Antimicrobial Cationic Peptides/pharmacology ; Moths/microbiology/drug effects ; Humans ; Carbapenem-Resistant Enterobacteriaceae/drug effects ; }, abstract = {UNLABELLED: Carbapenem-resistant Klebsiella pneumoniae (CRKP) and Escherichia coli (CREC) are frequently detected in clinical settings, restricting the use of carbapenems. Therefore, there is an urgent need for new antimicrobial strategies to address infections caused by CRKP and CREC. This study investigated the antibacterial, anti-biofilm, and anti-inflammatory effects of the cationic antimicrobial peptide Hs02, along with its potential antimicrobial mechanisms against CRKP and CREC. The results revealed that Hs02 had a low minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against CRKP and CREC, effectively eliminating the bacteria within 30 min. Moreover, Hs02 significantly prevents biofilm formation and disrupts the established biofilms. Further mechanistic studies demonstrated that Hs02 specifically targeted and bound to bacterial outer membrane lipopolysaccharides (LPS), disrupted membrane permeability and integrity, which led to intracellular reactive oxygen species (ROS) accumulation. Furthermore, Hs02 neutralized LPS, thereby suppressing the production of pro-inflammatory cytokines TNF-α, IL-6, and IL-1β in murine macrophage RAW 264.7 cells. In vitro, hemolysis and cytotoxicity assays confirmed Hs02's safety at the tested concentrations and proved that Hs02 improved the survival rate of Galleria mellonella larvae. In conclusion, the findings suggest that Hs02's interaction with LPS and the resulting disruption of membrane integrity may be key factors driving its rapid bactericidal and anti-inflammatory effects.<br><br>IMPORTANCE: Eukaryotic antimicrobial peptides are typically amphipathic peptides consisting of approximately 50 amino acids. Many macromolecular proteins in our body contain polypeptide sequences that show characteristics similar to those of antimicrobial peptides. The present research highlights a gap in the current literature regarding the mechanisms by which the intragenic antimicrobial peptide Hs02, derived from human proteins, exerts its rapid bactericidal and anti-inflammatory effects. The findings demonstrate that lipopolysaccharide (LPS) is a key target of Hs02's antimicrobial activity and that its ability to neutralize LPS is crucial for its anti-inflammatory effects.}, }
@article {pmid39624194, year = {2024}, author = {Eidaroos, NH and Eid, HI and Nasef, SAA and Mansour, GH and El-Tarabili, RM}, title = {The impact of quorum sensing and biofilm formation on antimicrobial resistance and virulence of XDR and MDR Pseudomonas aeruginosa in laying chickens.}, journal = {Iranian journal of veterinary research}, volume = {25}, number = {2}, pages = {125-134}, pmid = {39624194}, issn = {1728-1997}, abstract = {BACKGROUND: Pseudomonas aeruginosa plays a major influence on poultry outbreaks. Several factors may contribute to its pathogenicity.<br><br>AIMS: This study aimed to investigate the prevalence of P. aeruginosa infection among layer chickens with phenotypic and genotypic characterization of the isolates.<br><br>METHODS: Samples (n=160) were collected from respiratory distressed layer chickens according to the lesion and bacteriologically examined for isolation of P. aeruginosa from Sharkia province, Egypt. The antimicrobial sensitivity was performed against 18 antimicrobial agents. A qualitative assessment of biofilm production was performed using the Tube method. The isolates were genetically examined for confirmation, detection of quorum sensing genes, virulence genes, and biofilm production genes by conventional PCR.<br><br>RESULTS: P. aeruginosa was isolated from 25% of the samples. Moreover, 95% of the isolates were extensively drug-resistant (XDR) with multiple antibiotic resistance indices (MARI) of 0.67 to 0.83. A total of 38 isolates were able to produce biofilm with different degrees. PCR of 16S rRNA (P. aeruginosa) and oprL genes confirmed the existence of P. aeruginosa isolates. For quorum sensing genes, lasI and lasR were successfully amplified at 100% and 89.5%, respectively. For virulence genes, toxA and exoU were amplified by a percentage of 78.9%, while the higBA gene was in 100% of the isolates. pprA and pprB genes were amplified at 100% and 89.5%, respectively. For biofilm genes, pslA, fliC, and pelA were amplified in 100%, 84.2%, and 10.5%, respectively.<br><br>CONCLUSION: A strong correlation between quorum sensing genes, biofilm genes, and virulence genes was detected. Further, biofilm production increases the resistance of the isolates to antimicrobial agents.}, }
@article {pmid39624045, year = {2024}, author = {Niranjan, R and Patil, S and Dubey, A and Lochab, B and Priyadarshini, R}, title = {Small cyclic dipeptide produced by Lactobacillus rhamnosus with anti-biofilm properties against Streptococcus mutans biofilm.}, journal = {Biofilm}, volume = {8}, number = {}, pages = {100237}, pmid = {39624045}, issn = {2590-2075}, abstract = {The human oral cavity harbors many bacterial species collectively termed the oral microbiome and is integral for maintaining oral health. Dysbiosis of oral microbiota leads to common oral diseases, including dental caries, gingivitis, and periodontitis. Streptococcus mutans is the primary causative agent of dental caries. Studies have explored the use of probiotic Lactobacillus spp. to mitigate S. mutans biofilms. In the present study, we have tested the use of Lactobacillus rhamnosus extracts/metabolites for anti-biofilm properties. A small organic compound/metabolite was isolated from the cell-free supernatant of L. rhamnosus, and this metabolite resulted in a dose-dependent inhibition of S. mutans biofilms. Confocal microscopy revealed that the thickness of S. mutans biofilms was severely reduced upon metabolite treatment. With the help of FTIR spectra and mass spectrometry analysis, the molecular formula (C11H19O2N2) was deduced. The inhibitor compound was further identified as a small cyclic peptide, cyclo (-L-Leu-L-Pro). Our data also revealed that isolated metabolite impedes S. mutans biofilms by modulating gene expression of several essential genes involved in biofilm establishment.}, }
@article {pmid39622869, year = {2024}, author = {Wang, D and Wang, S and Sun, W and Chen, T and Liang, C and Yang, P and Liu, Q and Zhao, C and Chen, Y}, title = {Biofilm-based biocatalysis for β-cyclodextrin production by the surface-display of β-cyclodextrin glycosyltransferase in Bacillus subtilis.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {29925}, pmid = {39622869}, issn = {2045-2322}, support = {22178176//National Natural Science Foundation of China/ ; 22208157//National Natural Science Foundation of China/ ; 2022YFC2105400//National Key R&amp;D Program of China/ ; SICAM-XTA2201//Jiangsu National Synergetic Innovation Center for Advanced Materials/ ; 2023BEE01011//Key R&amp;D project of Ningxia Hui Autonomous Region/ ; SKL-MCE-22A04//State Key Laboratory of Materials-Oriented Chemical Engineering/ ; }, mesh = {*Bacillus subtilis/genetics/metabolism/enzymology ; *beta-Cyclodextrins/metabolism ; *Biofilms/growth &amp; development ; *Biocatalysis ; *Glucosyltransferases/metabolism/genetics ; Fermentation ; Temperature ; Hydrogen-Ion Concentration ; Bacterial Proteins/metabolism/genetics ; Enzymes, Immobilized/metabolism/genetics ; }, abstract = {β-cyclodextrin (β-CD) is an important cyclic oligosaccharide, which is widely applicated in foods, environmental protection, and cosmetics, primarily prepared from enzymatic synthesis in traditional industry. However, several challenges persist, including cumbersome processes and difficulties in achieving continuous fermentation and catalysis. This research introduced a biofilm-based immobilized fermentation, integrating with enzyme catalysis system of surface display in Bacillus subtilis. The bslA gene was selected to construct the surface display system due to its ability to promote biofilm formation and serve as an anchorin. Compared to free cell catalysis, the biofilm-based immobilized catalysis expanded the temperature range to 40-70 and the pH range to 5-7.5. During the continuous catalysis process, by the 13th batch, the relative activity remained around 52%, and the conversion rate exceeded 36%, similar to the single-batch free cell catalysis. These findings provide valuable insights and effective strategies for the industrial production of β-CD and other biochemicals through continuous catalysis.}, }
@article {pmid39622673, year = {2024}, author = {Lai, L and Ding, W and Huang, G and Wang, M and Chen, J and Lai, L and Deng, X and Tang, L and Yu, X and Huang, Y and Truong, TMH and Zhang, Z and Ding, W}, title = {Preparation and Methicillin-Resistant Staphylococcus aureus Biofilm Elimination Effect of Baicalein-Loaded Hyaluronic acid/β-Cyclodextrin grafted Chitosan Nanoparticles.}, journal = {Biomedical and environmental sciences : BES}, volume = {37}, number = {10}, pages = {1227-1231}, doi = {10.3967/bes2024.160}, pmid = {39622673}, issn = {2214-0190}, }
@article {pmid39622419, year = {2025}, author = {Niu, H and Zhu, D and Leng, J and Wang, Z and Liu, D and Chen, Y and Yang, P and Ying, H}, title = {Biofilm-based immobilized fermentation of engineered Komagataella phaffii for xylanase production.}, journal = {Bioresource technology}, volume = {418}, number = {}, pages = {131918}, doi = {10.1016/j.biortech.2024.131918}, pmid = {39622419}, issn = {1873-2976}, mesh = {*Biofilms ; *Fermentation ; *Endo-1,4-beta Xylanases/metabolism ; *Saccharomycetales/metabolism ; }, abstract = {This study presented an immobilized fermentation process of engineered Komagataella phaffii with improved biofilm-forming abilities for continuous xylanase production and provided the first insights into the molecular basis of biofilm-based immobilized fermentation of K. phaffii. Overexpression of PAS_chr2-2_0178 and PAS_FragB_0067 in K. phaffii facilitated biofilm formation with 31.6% and 113.8% increasement, respectively. Subsequently, a biofilm-based immobilized fermentation process was developed for the PAS_FragB_0067-overexpressing strain. Xylanase production over five batches by GS115-0067* was better than that of GS115-xyn, with an overall average of 35.4 % higher enzyme activity. PAS_FragB_0067 overexpression resulted in better adhesion of K. phaffii cells on the carrier, and enhanced biofilms could provide more active cells in the immobilized fermentation process. Transcriptome analysis revealed that overexpression of the biofilm-related gene promoted central carbon metabolism. These findings offer a valuable reference strategy to improve production efficiency of K. phaffii cells in continuous fermentation processes.}, }
@article {pmid39621768, year = {2024}, author = {Weerasekera, R and Moreau, A and Huang, X and Nam, KM and Hinbest, AJ and Huynh, Y and Liu, X and Ashwood, C and Pepi, LE and Paulson, E and Cegelski, L and Yan, J and Olson, R}, title = {Vibrio cholerae RbmB is an α-1,4-polysaccharide lyase with biofilm-disrupting activity against Vibrio polysaccharide (VPS).}, journal = {PLoS pathogens}, volume = {20}, number = {12}, pages = {e1012750}, pmid = {39621768}, issn = {1553-7374}, support = {DP2 GM146253/GM/NIGMS NIH HHS/United States ; R01 GM117278/GM/NIGMS NIH HHS/United States ; R15 GM152959/GM/NIGMS NIH HHS/United States ; }, mesh = {*Biofilms/growth &amp; development/drug effects ; *Vibrio cholerae/enzymology/genetics ; *Polysaccharide-Lyases/metabolism/genetics/chemistry ; *Polysaccharides, Bacterial/metabolism ; *Bacterial Proteins/metabolism/genetics/chemistry ; Cholera/microbiology ; Humans ; }, abstract = {Many pathogenic bacteria form biofilms as a protective measure against environmental and host hazards. The underlying structure of the biofilm matrix consists of secreted macromolecules, often including exopolysaccharides. To escape the biofilm, bacteria may produce a number of matrix-degrading enzymes, including glycosidic enzymes that digest exopolysaccharide scaffolds. The human pathogen Vibrio cholerae assembles and secretes an exopolysaccharide called VPS (Vibrio polysaccharide) which is essential in most cases for the formation of biofilms and consists of a repeating tetrasaccharide unit. Previous studies have indicated that a secreted glycosidase called RbmB is involved in V. cholerae biofilm dispersal, although the mechanism by which this occurs is not understood. To approach the question of RbmB function, we recombinantly expressed and purified RbmB and tested its activity against purified VPS. Using a fluorescence-based biochemical assay, we show that RbmB specifically cleaves VPS in vitro under physiological conditions. Analysis of the cleavage process using mass spectrometry, solid-state NMR, and solution NMR indicates that RbmB cleaves VPS at a specific site (at the α-1,4 linkage between D-galactose and a modified L-gulose) into a mixture of tetramers and octamers. We demonstrate that the product of the cleavage contains a double bond in the modified guluronic acid ring, strongly suggesting that RbmB is cleaving using a glycoside lyase mechanism. Finally, we show that recombinant RbmB from V. cholerae and the related aquatic species Vibrio coralliilyticus are both able to disrupt living V. cholerae biofilms. Our results support the role of RbmB as a polysaccharide lyase involved in biofilm dispersal, as well as an additional glycolytic enzyme to add to the toolbox of potential therapeutic antibacterial enzymes.}, }
@article {pmid39621545, year = {2024}, author = {Zheng, Z and Chen, J and Srinual, S and Tumbas Šaponjac, V and Yin, T and Wang, BY and Sun, R and Hu, M}, title = {Buprenorphine Salivary Gland Accumulation Sustaining High Oral Fluid Exposure and Increasing the Risk of Streptococcus mutans Biofilm Formation.}, journal = {Journal of addiction medicine}, volume = {}, number = {}, pages = {}, doi = {10.1097/ADM.0000000000001401}, pmid = {39621545}, issn = {1935-3227}, abstract = {OBJECTIVES: The US Food and Drug Administration (FDA) issued a warning about buprenorphine-induced dental caries of unknown mechanism in 2022. To investigate the potential mechanism, the association between local buprenorphine exposure and dental biofilm formation will be explored in this study.<br><br>METHODS: Female F344 rats were dosed with sublingual buprenorphine film or intravenous injection to explore the oral cavity exposure of the buprenorphine. The buprenorphine distribution in salivary glands after the sublingual and intravenous administration was also evaluated. To investigate the effects of buprenorphine exposure on dental caries formation, buprenorphine's impact on the biofilm formation of S. mutans in vitro was measured.<br><br>RESULTS: The absolute sublingual bioavailability of buprenorphine in rats was 17.8% with a high ratio of oral fluid exposure to blood concentration in the pharmacokinetic study. Salivary gland concentrations of buprenorphine and its active metabolite norbuprenorphine were significantly higher than their blood concentrations after both sublingual (s.l.) and intravenous (i.v.) administration. Correlation analysis showed that the oral fluid concentration of buprenorphine and norbuprenorphine was highly correlated to salivary gland concentration rather than blood concentration. These data indicate that the salivary gland serves as an accumulation organ for buprenorphine, allowing prolonged oral fluid exposure to buprenorphine. Lastly, buprenorphine and its metabolites contributed to the biofilm formation of S. mutans in high concentration.<br><br>CONCLUSIONS: Sublingual administration substantially increased the salivary gland distribution of buprenorphine and norbuprenorphine. Depot effects following sublingual dosing and salivary gland accumulation likely sustained high oral fluid exposure to buprenorphine and stimulated the biofilm formation of S. mutans.}, }
@article {pmid39618743, year = {2024}, author = {Kurtzman, GM and Horowitz, RA and Johnson, R and Pedro, Z}, title = {Oral Biofilm and Its Connection to Alzheimer's Disease.}, journal = {Cureus}, volume = {16}, number = {11}, pages = {e72841}, pmid = {39618743}, issn = {2168-8184}, abstract = {Dementia and Alzheimer's disease are common occurrences in the population, affecting many patients. Recent research and studies have found a link between oral biofilm and the initiation of these conditions or the worsening of their presentation. Periodontal disease and the associated oral biofilm with its bacteria are often not considered by the medical community when treating these or their patients. Coordination of therapy with a dentist can improve the patient's oral health. Decreasing bacteria in the oral biofilm allows the physician and dentist to provide coordinated total healthcare. Emphasis and education of the patient on the importance of maintaining good oral homecare and routine dental recall prophylaxis appointments to improve their systemic health and limit the progression and worsening of mental health conditions. This article discusses the connection between oral biofilm and systemic health, specifically Alzheimer's disease, and how to improve those conditions through oral healthcare.}, }
@article {pmid39618639, year = {2024}, author = {Ganjo, AR}, title = {Evaluation of the Anti-biofilm Activity of Vitamins Against Acinetobacter baumannii and Klebsiella pneumoniae Recovered From Clinical Specimens: An In Vitro and In Silico Analysis.}, journal = {Cureus}, volume = {16}, number = {10}, pages = {e72679}, pmid = {39618639}, issn = {2168-8184}, abstract = {INTRODUCTION: Pathogens that form biofilms reduce the effectiveness of conventional treatments and promote antibiotic resistance. Therefore, this study aimed to investigate the antibiofilm properties of vitamin C (ascorbic acid) and vitamin D (cholecalciferol) experimentally.<br><br>METHODS: The antibiofilm properties of the studied compounds were evaluated using molecular docking analyses. AutoDock Vina software (The Scripps Research Institute, La Jolla, California) was used to assess the binding affinity of vitamins C and D to the active sites of biofilm-related proteins.<br><br>RESULTS: Molecular docking revealed different affinities toward the active sites of the target proteins. The interactions showed promising results, with vitamin D forming both hydrogen bonds and hydrophobic interactions. Compared to vitamin C, vitamin D exhibited the highest binding affinity, with a score of -10.8 kcal/mol.<br><br>CONCLUSION: However, molecular dynamics simulations are needed to further elucidate the dynamic behaviors and stability of these compound-protein complexes. Vitamin D demonstrated good in vitro potential as an anti-biofilm agent and should be considered for use alongside antibiotics in the treatment of bacterial infections.}, }
@article {pmid39617946, year = {2024}, author = {Miguélez-Pérez, R and Mencía-Ares, O and Gutiérrez-Martín, CB and González-Fernández, A and Petrocchi-Rilo, M and Delgado-García, M and Martínez-Martínez, S}, title = {Biofilm formation in Streptococcus suis: in vitro impact of serovars and assessment of coinfections with other porcine respiratory disease complex bacterial pathogens.}, journal = {Veterinary research}, volume = {55}, number = {1}, pages = {157}, pmid = {39617946}, issn = {1297-9716}, mesh = {Animals ; *Streptococcus suis/physiology ; *Biofilms/growth &amp; development ; *Swine Diseases/microbiology ; Swine ; *Coinfection/veterinary/microbiology ; *Streptococcal Infections/veterinary/microbiology ; *Serogroup ; Spain ; }, abstract = {Streptococcus suis is a worldwide pathogen that impacts the swine industry, causing severe clinical signs, including meningitis and arthritis, in postweaning piglets. A key virulence mechanism of S. suis is biofilm formation, which improves its persistence and resistance to external factors. Here, we assessed the in vitro biofilm formation of 240 S. suis isolates from Spanish swine farms and evaluated the effects of serovars (SVs) and coinfections with other porcine respiratory disease complex (PRDC) pathogens. Our study revealed significant heterogeneity in biofilm formation among S. suis SVs. Notably, SV2 resulted in the lowest degree of biofilm formation, in contrast with the high biofilm-forming capacities of SV1, SV7, and SV9. Other PRDC pathogens, including Actinobacillus pleuropneumoniae, Glaesserella parasuis, and Pasteurella multocida, formed biofilms, although they were generally less robust than those of S. suis (except for SV2), which contrasts with the high biofilm formation of Staphylococcus hyicus. Coinfections enhanced biofilm formation in mixed cultures of S. suis, particularly with P. multocida. Other coinfections revealed variable results in pathogen interactions, suggesting the potential of biofilms for increased persistence and pathogenicity in coinfections. In conclusion, this study underscores the importance of serovar-specific differences in biofilm formation among S. suis isolates, with significant implications for pathogenicity and persistence. The heterogeneous biofilm formation observed in coinfections with other PRDC pathogens reveals a complex interplay that could exacerbate disease severity. These findings provide a foundation for further research on biofilm mechanisms to mitigate the impact of PRDC in the swine industry.}, }
@article {pmid39617560, year = {2025}, author = {Wang, Y and Zhang, Y and Zhu, X and Tang, Y and Zhang, Y}, title = {Plasmid-mediated transfer of antibiotic resistance genes and biofilm formation in a simulated drinking water distribution system under chlorine pressure.}, journal = {Journal of environmental sciences (China)}, volume = {152}, number = {}, pages = {376-388}, doi = {10.1016/j.jes.2024.05.021}, pmid = {39617560}, issn = {1001-0742}, mesh = {*Biofilms/drug effects ; *Chlorine ; *Drinking Water/microbiology ; *Plasmids/genetics ; *Disinfectants ; *Drug Resistance, Microbial/genetics ; Water Microbiology ; Water Purification/methods ; Genes, Bacterial ; }, abstract = {The effects of disinfectants and plasmid-based antibiotic resistance genes (ARGs) on the growth of microorganisms and the plasmid-mediated transfer of ARGs in the water and biofilm of the drinking water distribution system under simulated conditions were explored. The heterotrophic plate count of the water in reactors with 0.1 mg/L NaClO and NH2Cl was higher than in the control groups. There was no similar phenomenon in biofilm. In the water of reactors containing NaClO, the aphA and bla genes were lower than in the antibiotic resistant bacteria group, while both genes were higher in the water of reactors with NH2Cl than in the control group. Chloramine may promote the transfer of ARGs in the water phase. Both genes in the biofilm of the reactors containing chlorine were lower than the control group. Correlation analysis between ARGs and water quality parameters revealed that the copy numbers of the aphA gene were significantly positively correlated with the copy numbers of the bla gene in water and significantly negatively correlated in biofilm (p < 0.05). The results of the sequencing assay showed that bacteria in the biofilm, in the presence of disinfectant, were primarily Gram-negative. 1.0 mg/L chlorine decreased the diversity of the community in the biofilm. The relative abundance of some bacteria that may undergo transfer increased in the biofilm of the reactor containing 0.1 mg/L chlorine.}, }
@article {pmid39616895, year = {2025}, author = {Xu, L and Zhang, X and Wang, W and Shen, J and Ma, K and Wang, H and Xue, T}, title = {The global regulator SpoVG is involved in biofilm formation and stress response in foodborne Staphylococcus aureus.}, journal = {International journal of food microbiology}, volume = {428}, number = {}, pages = {110997}, doi = {10.1016/j.ijfoodmicro.2024.110997}, pmid = {39616895}, issn = {1879-3460}, mesh = {*Biofilms/growth &amp; development ; *Staphylococcus aureus/genetics/physiology ; *Bacterial Proteins/genetics/metabolism ; *Gene Expression Regulation, Bacterial ; Stress, Physiological ; Food Microbiology ; Oxidative Stress ; Micrococcal Nuclease/metabolism/genetics ; Promoter Regions, Genetic ; Staphylococcal Food Poisoning/microbiology ; Hot Temperature ; }, abstract = {Staphylococcus aureus (S. aureus) is a primary culprit of food poisoning. As a highly adaptable pathogen, S. aureus demonstrates formidable biofilm-forming and stress tolerance capabilities, inducing significant challenges to eradicate food contamination caused by this organism. SpoVG, a regulatory protein in S. aureus, controls the expression of numerous genes. However, its role in biofilm formation and stress response in foodborne S. aureus remains to be elucidated. In this study, we investigated the functions of SpoVG involved in food-related stress responses and biofilm formation in S. aureus RMSA50. The results demonstrated that SpoVG deletion enhanced biofilm formation and resistance to heat and desiccation, while decreased tolerance to oxidative stress. Further analysis revealed that cell aggregation and the accumulation of extracellular DNA (eDNA) may contribute to the enhanced biofilm formation. Real-time quantitative reverse transcription-PCR (RT-qPCR) revealed that the expression levels of nuc and sasC, which are related to cell aggregation and eDNA concentration, were significantly altered in the spoVG mutant. Electrophoretic mobility shift assays (EMSA) confirmed that SpoVG directly binds to the promoter region of nuc and sasC to regulate their expression. These findings suggest that SpoVG may serve as a target to decrease biofilm formation and control S. aureus contamination in the food industry.}, }
@article {pmid39615850, year = {2024}, author = {Gómez-Martínez, D and Selvin, MA and Nilsson, AK and Carmona, E and Ngou, JS and Kristiansson, E and Nilsson, RH and Corcoll, N}, title = {Environmental concentrations of the fungicide tebuconazole alter microbial biodiversity and trigger biofilm-released transformation products.}, journal = {Chemosphere}, volume = {369}, number = {}, pages = {143854}, doi = {10.1016/j.chemosphere.2024.143854}, pmid = {39615850}, issn = {1879-1298}, mesh = {*Biofilms/drug effects ; *Triazoles/toxicity ; *Water Pollutants, Chemical/toxicity ; *Biodiversity ; *Fungicides, Industrial/toxicity ; *Fungi/drug effects/genetics ; Bacteria/drug effects/genetics/classification/metabolism ; Biotransformation ; }, abstract = {Freshwater microbial communities are integral components of riverine biodiversity. The ecological effects of toxic chemical pollutants, such as fungicides (e.g., tebuconazole), on microbial abundance and diversity are needed for risk assessment and regulation. The emergence of RNA metabarcoding approaches allow us to describe at unprecedented resolution the microbial diversity of the active part of a microbial community. Our study assesses the ecotoxicological impact of chronic and acute tebuconazole exposures on fungal, bacterial, and algal biomass and biodiversity of aquatic fungi and bacteria in stream biofilms using an RNA metabarcoding approach. In addition, the study uses HPLC-MS to evaluate the capability of biofilms to metabolize tebuconazole. Natural biofilm communities from a Swedish stream were exposed chronically (24 days) and acutely (96 h) to environmental concentrations of tebuconazole (10 and 100 μg/L) in microcosms conditions. The diversity and community structure of fungi and bacteria was assessed by ITS2 and 16S cDNA amplicon-sequencing, respectively. Biofilms chronically exposed to tebuconazole produced and released unidentified transformation products into the water column, suggesting a biotransformation capability following 24 days of uninterrupted exposure. The fungal biomass markedly decreased by a biomass loss of 40% when chronically exposed to 10 μg/L, and 60% when chronically exposed to 100 μg/L. Bacterial and algal biomass remained comparable with the controls in all tebuconazole treatments. Fungal and bacterial alpha diversity metrics were not significantly impacted, although a decreasing trend in fungal richness was observed with the treatments. However, beta diversity was significantly impacted in both fungal and bacterial compartments. Chronic exposures resulted in a shift in community composition, where taxa potentially more tolerant to tebuconazole (i.e. Lecanoromycetes) replaced more sensitive taxa (i.e. Malasseziomycetes). This study indicates that tebuconazole at environmental concentrations might pose a risk to freshwater systems, mainly due to its high toxicity to fungi.}, }
@article {pmid39615760, year = {2025}, author = {Ni, M and Pan, Y and Gong, J and Chen, Z and Li, D and Huang, Y and Li, L and Ding, Y and Bi, Z}, title = {Glycogen-accumulating organisms promote phosphate recovery from wastewater by pilot-scale biofilm sequencing batch reactor: Performance and mechanism.}, journal = {Bioresource technology}, volume = {418}, number = {}, pages = {131910}, doi = {10.1016/j.biortech.2024.131910}, pmid = {39615760}, issn = {1873-2976}, mesh = {*Biofilms ; *Bioreactors ; *Wastewater/chemistry ; *Glycogen/metabolism ; *Phosphates/metabolism ; Pilot Projects ; Quorum Sensing ; Carbon/metabolism ; Acyl-Butyrolactones/metabolism ; Water Purification/methods ; }, abstract = {A high phosphate (P) recovery concentration was achieved in pilot-scale biofilm sequencing batch reactor (BSBR) with a low carbon source (C) cost. Especially, a high-abundance glycogen-accumulating organisms (GAOs) (13.93-31.72%) was detected that was accompanied by a high P recovery concentration of BSBR. High-abundance GAOs obtain additional C through various C compensation pathways (split tricarboxylic acid cycle (TCA cycle), glyoxylate shunt and gluconeogenesis), thus reducing the need to compete with polyphosphate-accumulating organisms (PAOs) for C and weakening the adverse effects on P recovery by PAO cells. Under the action of N-acyl homoserine lactones (AHLs)-mediated quorum sensing (QS), GAOs promoted the secretion of a large amount of extracellular polymeric substances (EPS), which helped to realize the P recovery of EPS-dominated biofilms (68.02%-96.89%). This study provides a low-carbon technology for the recovery of high concentration P from municipal wastewater, and improves the ecological theory of P recovery in collaboration with GAOs and PAOs.}, }
@article {pmid39615759, year = {2025}, author = {Zhang, H and Zhang, J and Fan, S and Lu, J and Zhang, W and Ding, W}, title = {Synthetic biofilm community for efficient phosphorus removal from high-salinity wastewater.}, journal = {Bioresource technology}, volume = {418}, number = {}, pages = {131902}, doi = {10.1016/j.biortech.2024.131902}, pmid = {39615759}, issn = {1873-2976}, mesh = {*Biofilms ; *Phosphorus ; *Wastewater/microbiology/chemistry ; *Bacteria/metabolism/genetics ; *Salinity ; Water Purification/methods ; Biodegradation, Environmental ; Polyphosphates/metabolism ; }, abstract = {Substantial amounts of phosphorus are discharged into water bodies, leading to an urgent need to develop methods for phosphorus removal. Here, 12 novel polyphosphate-accumulating organisms were identified from marine biofilms through genomic screening and incorporated into a stable community for phosphorus removal from high-salinity water. The synthetic biofilm community achieved an 82% removal efficiency in a marine broth medium. Electron microscopy showed storage of polyphosphate particles in the bacterial cells. Metatranscriptomic analysis indicated expression changes of genes for phosphate transport, as well as relevant metabolic pathways. In particular, pst genes encoding transporters with high phosphate affinity were downregulated at high-phosphorus concentration, whereas pit genes encoding transporters with low phosphate affinity were constitutively expressed. Furthermore, the synthetic biofilm community exhibited remarkable efficiency in removing over 92% of phosphorus from fish farming facility wastewater. Taken together, synthetic community using marine biofilm bacteria is a new strategy of phosphorus removal.}, }
@article {pmid39615517, year = {2024}, author = {Cordero García-Galán, E and Medel-Plaza, M and Pozo-Kreilinger, JJ and Sarnago, H and Lucía, &#xd3; and Rico-Nieto, A and Esteban, J and Gomez-Barrena, E}, title = {In vivo reduction of biofilm seeded on orthopaedic implants.}, journal = {Bone &amp; joint research}, volume = {13}, number = {12}, pages = {695-702}, pmid = {39615517}, issn = {2046-3758}, support = {//Fundaci&#xf3;n Mutua Madrile&#xf1;a/ ; }, abstract = {AIMS: Electromagnetic induction heating has demonstrated in vitro antibacterial efficacy over biofilms on metallic biomaterials, although no in vivo studies have been published. Assessment of side effects, including thermal necrosis of adjacent tissue, would determine transferability into clinical practice. Our goal was to assess bone necrosis and antibacterial efficacy of induction heating on biofilm-infected implants in an in vivo setting.<br><br>METHODS: Titanium-aluminium-vanadium (Ti6Al4V) screws were implanted in medial condyle of New Zealand giant rabbit knee. Study intervention consisted of induction heating of the screw head up to 70&#xb0;C for 3.5 minutes after implantation using a portable device. Both knees were implanted, and induction heating was applied unilaterally keeping contralateral knee as paired control. Sterile screws were implanted in six rabbits, while the other six received screws coated with Staphylococcus aureus biofilm. Sacrifice and sample collection were performed 24, 48, or 96 hours postoperatively. Retrieved screws were sonicated, and adhered bacteria were estimated via drop-plate. Width of bone necrosis in retrieved femora was assessed through microscopic examination. Analysis was performed using non-parametric tests with significance fixed at p &#x2264; 0.05.<br><br>RESULTS: The width of necrosis margin in induction heating-treated knees ranged from 0 to 650 &#x3bc;m in the sterile-screw group, and 0 to 517 &#x3bc;m in the biofilm-infected group. No significant differences were found between paired knees. In rabbits implanted with sterile screws, no bacteria were detected. In rabbits implanted with infected screws, a significant bacterial load reduction with median 0.75 Log10 colony-forming units/ml was observed (p = 0.016).<br><br>CONCLUSION: Induction heating was not associated with any demonstrable thermal bone necrosis in our rabbit knee model, and might reduce bacterial load in S. aureus biofilms on Ti6Al4V implants.}, }
@article {pmid39614912, year = {2024}, author = {Petchimuthu, R and Sundar, K and Balakrishnan, V}, title = {Characterization, immobilization and evaluation of anti-Pseudomonas aeruginosa biofilm activity of alginate lyase from marine bacterium, Enterobacter tabaci RAU2C.}, journal = {Biotechnology letters}, volume = {47}, number = {1}, pages = {9}, pmid = {39614912}, issn = {1573-6776}, support = {KARE/VC/R&amp;D/SMPG/2023-2024/01//Kalasalingam Academy of Research and Education/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Polysaccharide-Lyases/metabolism/pharmacology/chemistry ; *Pseudomonas aeruginosa/drug effects/physiology/enzymology ; *Enzymes, Immobilized/metabolism/chemistry/pharmacology ; *Enterobacter/drug effects/enzymology/physiology ; Hydrogen-Ion Concentration ; *Anti-Bacterial Agents/pharmacology ; Alginates/chemistry/pharmacology/metabolism ; Temperature ; Kinetics ; Enzyme Stability ; }, abstract = {Alginate lyases have the potential to be used as a therapeutic agent for P. aeruginosa infections. The present work was focused on the characterization of free and immobilized alginate lyase produced by marine bacteria, Enterobacter tabaci RAU2C isolated previously in the laboratory for alginate lyase production and exploring the potential of alginate lyase as an anti-biofilm agent against the P. aeruginosa biofilm. RAU2C alginate lyase was immobilized using an epoxy-activated curdlan matrix by three different methods. Further, the free and immobilized were characterized for its optimal pH and temperature. The effect of alginate concentration on alginate lyase activity was assessed and the kinetic parameters were evaluated. The anti-biofilm activity of the crude alginate lyase was studied using biofilm inhibition and disruption assays in microtiter plates with crystal violet. The biofilm disruption by RAU2C alginate lyase was also ascertained by microscopic analysis. The immobilization matrix prepared using method 3 had a better binding capacity compared to other methods. Both soluble and immobilized alginate lyase exhibited optimal activity at 37 °C and pH 7.0. Km and Vmax of soluble and immobilized alginate lyase were found to be 3.38 mg/mL, 22.98 mg/mL min and 3.67 mg/mL and 26.59 mg/mL min respectively. Both microtiter assay and microscopic analysis confirmed the prevention and dispersal of pre-existing biofilms by crude RAU2C alginate lyase, highlighting its potential as an anti-biofilm agent against P. aeruginosa. The study highlights the efficacy of RAU2C alginate lyase as an anti-biofilm agent in controlling P. aeruginosa biofilms.}, }
@article {pmid39614893, year = {2024}, author = {Nath, R and Lahiri, D and Nag, M and Mahapatra, D and Bhattacharya, M and Dutta, K and Bhattacharya, D}, title = {Antibiofilm activity of exopolysaccharide-mediated ZnO nanoparticle against Pseudomonas aeruginosa biofilm.}, journal = {Naunyn-Schmiedeberg's archives of pharmacology}, volume = {}, number = {}, pages = {}, pmid = {39614893}, issn = {1432-1912}, abstract = {Exopolysaccharides (EPSs) are the group of biological macromolecules those play a potent role in protecting the bacteria from any sorts of stress. They exhibit multifunctional roles in natural and bioactive product science hence exhibits various types of medical and biochemical applications. EPS ensures the storage of nutrients, produce antigens to create defense mechanism during infection, and is also responsible for the formation of biofilm and cell adhesion. Green synthesis of ZnO nanoparticle mediated by EPS from Lactobacillus sp. which is a type of lactic acid bacteria (LAB) is a novel approach for its application in the food industry as it exhibits antimicrobial and antibiofilm potential. In this study, Lactobacillus sp. was cultivated in Lactobacillus broth media (LBM) and glucose mineral salt media (GMSM) to identify the best suitable media that would provide maximum amount of EPS, and it was observed that the two media exhibited maximum yield of 0.8 g/L and 0.6 g/L respectively after 48-h incubation. SEM, EDS, and XRD were used for characterizing the green synthesized ZnONPs from the EPS and was observed that the NPs were synthesized. 62.6% and 67.6% ZnONPs were observed in LBM-ZnONP and GMSM-ZnONP respectively from XRD analysis. UV spectroscopic detection showed corresponding peak of the nanoparticle formed at 349 nm which confirmed the production of ZnO NPs. Scanning electron microscopic (SEM) images and Fourier transform infrared spectroscopy (FT-IR) established the average size, shape, and composition of the nanoparticles. The peaks of the FT-IR also revealed the presence of the C = H and N-H stretching (1 H). It was also observed that the average size of LBM ZnONPs were 60.578 nm whereas GMSM ZnONPs were 53.09 nm. Viability studies exhibited that the NPs brought considerable reduction of the sessile cells of P. aeuginosa. It was further observed that the cells treated with NPs did not show revival. The NPs were able to inhibit the quorum sensing (QS) mechanism of Pseudomonas aeruginosa thereby preventing the development of virulence. Out of the two NPs, it was observed that GMSM ZnONPs showed better efficacy in comparison to LBM ZnONPs. Thus, the study concludes that EPS-mediated NPs can be used effectively in the process of treating the biofilm.}, }
@article {pmid39614781, year = {2024}, author = {Janež, N and Ladányi, M and Sterniša, M and Jug, B and Zupan, T and Peternel, T and Sebastijanović, A and Perišić Nanut, M and Karničar, K and Taler-Verčič, A and Turk, D and Klančnik, A and Štrancar, J and Sabotič, J}, title = {Exposure to specific fungal lectins during adhesion impairs biofilm formation of Listeria on polystyrene.}, journal = {Microbial biotechnology}, volume = {17}, number = {12}, pages = {e70040}, pmid = {39614781}, issn = {1751-7915}, support = {J2-50064//Javna Agencija za Raziskovalno Dejavnost RS/ ; J4-1771//Javna Agencija za Raziskovalno Dejavnost RS/ ; J4-2543//Javna Agencija za Raziskovalno Dejavnost RS/ ; J4-4555//Javna Agencija za Raziskovalno Dejavnost RS/ ; P4-0116//Javna Agencija za Raziskovalno Dejavnost RS/ ; P4-0127//Javna Agencija za Raziskovalno Dejavnost RS/ ; P4-0432//Javna Agencija za Raziskovalno Dejavnost RS/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Listeria/drug effects/physiology/growth &amp; development ; *Lectins/pharmacology/metabolism ; *Listeria monocytogenes/physiology/drug effects/growth &amp; development ; *Bacterial Adhesion/drug effects ; *Polystyrenes ; Fungal Proteins/metabolism/genetics ; Microbial Viability/drug effects ; Fungi/physiology/drug effects ; Temperature ; Anti-Bacterial Agents/pharmacology ; }, abstract = {Listeria monocytogenes is a pathogenic bacterium that can form biofilms in food processing plants, allowing the bacteria to survive despite the control measures applied. As the surface of the bacteria is covered with versatile polysaccharides and proteins, these influence the interactions of the bacterium with any surface. The unique properties and high stability of fungal proteins make them good candidates for the control of bacteria by targeting surface structures. We screened a group of fungal lectins and protease inhibitors from different fungal species, protein folds and known targets for their antibacterial and antibiofilm activity against model strains of Listeria innocua and Listeria monocytogenes. Several of them significantly decreased the viability of biofilm bacteria, but had no effect on bacterial growth parameters at 37°C and thus had no antibacterial activity. Fungal lectins significantly impaired biofilm development even at room temperature, which was attributed to exposure to lectins during adhesion. The tested fungal proteins also reduced biofilm development on biological model surfaces. The observed antibiofilm activity of fungal proteins suggests that they have the potential to modulate interactions between bacteria and/or between bacteria and surfaces, which could be used in the future to reduce surface contamination by Listeria.}, }
@article {pmid39612475, year = {2025}, author = {Lopez, AE and Mayoral, J and Zheng, H and Cianciotto, NP}, title = {Legionella pneumophila IrsA, a novel, iron-regulated exoprotein that facilitates growth in low-iron conditions and modulates biofilm formation.}, journal = {Microbiology spectrum}, volume = {13}, number = {1}, pages = {e0231324}, pmid = {39612475}, issn = {2165-0497}, support = {R01 AI139054/AI/NIAID NIH HHS/United States ; R25 GM079300/GM/NIGMS NIH HHS/United States ; T32 AI007476/AI/NIAID NIH HHS/United States ; }, mesh = {*Legionella pneumophila/genetics/metabolism/growth &amp; development/physiology ; *Biofilms/growth &amp; development ; *Iron/metabolism ; *Bacterial Proteins/genetics/metabolism ; *Gene Expression Regulation, Bacterial ; Legionnaires' Disease/microbiology ; Humans ; }, abstract = {To discover new factors that are involved in iron acquisition by Legionella pneumophila, we used RNA-Seq to identify the genes that are most highly induced when virulent strain 130b is cultured in a low-iron chemically defined medium. Among other things, this revealed 14915, a heretofore uncharacterized gene that is predicted to be transcriptionally regulated by Fur and to encode a novel, ~15 kDa protein. 14915 was present in all L. pneumophila strains examined and had homologs in a subset of the other Legionella species. Compatible with it containing a classic signal sequence, the 14915 protein was detected in bacterial culture supernatants in a manner dependent upon the L. pneumophila type II secretion system. Thus, we designated 14915 as IrsA for iron-regulated, secreted protein A. Based on mutant analysis, the irsA gene was not required for optimal growth of strain 130b in low-iron media. However, after discovering that the commonly used laboratory-derived strain Lp02 has a much greater requirement for iron, we uncovered a growth-enhancing role for IrsA after examining an Lp02 mutant that lacked both IrsA and the Fe[2+]-transporter FeoB. The irsA mutant of 130b, but not its complemented derivative, did, however, display increased biofilm formation on both plastic and agar surfaces, and compatible with this, the mutant hyper-aggregated. Thus, IrsA is a novel, iron-regulated exoprotein that modulates biofilm formation and, under some circumstances, promotes growth in low-iron conditions. For this study, we determined and deposited in the database a complete and fully assembled genome sequence for strain 130b.IMPORTANCEThe bacterium Legionella pneumophila is the principal cause of Legionnaires' disease, a potentially fatal form of pneumonia that is increasing in incidence. L. pneumophila exists in many natural and human-made water systems and can be transmitted to humans through inhalation of contaminated water droplets. L. pneumophila flourishes within its habitats by spreading planktonically, assembling into biofilms, and growing in larger host cells. Iron acquisition is a key determinant for L. pneumophila persistence in water and during infection. We previously demonstrated that L. pneumophila assimilates iron both by secreting a non-protein iron chelator (siderophore) and by importing iron through membrane transporters. In this study, we uncovered a novel, secreted protein that is highly iron-regulated, promotes L. pneumophila's growth in low-iron media, and impacts biofilm formation. We also identified uncharacterized, IrsA-related proteins in other important human and animal pathogens. Thus, our results have important implications for understanding iron assimilation, biofilm formation, and pathogenesis.}, }
@article {pmid39612218, year = {2025}, author = {De Bleeckere, A and van Charante, F and Debord, T and Vandendriessche, S and De Cock, M and Verstraete, M and Lamret, F and Lories, B and Boelens, J and Reffuveille, F and Steenackers, HP and Coenye, T}, title = {A novel synthetic synovial fluid model for investigating biofilm formation and antibiotic susceptibility in prosthetic joint infections.}, journal = {Microbiology spectrum}, volume = {13}, number = {1}, pages = {e0198024}, pmid = {39612218}, issn = {2165-0497}, support = {G066523N//Fonds Wetenschappelijk Onderzoek (FWO)/ ; W000921N//Fonds Wetenschappelijk Onderzoek (FWO)/ ; SG Research Grant//European Society of Clinical Microbiology and Infectious Diseases (ESCMID)/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Prosthesis-Related Infections/microbiology/drug therapy ; *Synovial Fluid/microbiology ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology ; Humans ; Bacteria/drug effects/growth &amp; development/isolation &amp; purification ; Pseudomonas aeruginosa/drug effects/physiology/growth &amp; development ; Staphylococcus aureus/drug effects/physiology ; Candida/drug effects/physiology/growth &amp; development ; Escherichia coli/drug effects/physiology/growth &amp; development ; }, abstract = {UNLABELLED: There is growing evidence that bacteria encountered in prosthetic joint infections (PJIs) form surface-attached biofilms on prostheses, as well as biofilm aggregates embedded in synovial fluid and tissues. However, in vitro models allowing the investigation of these biofilms and the assessment of their antimicrobial susceptibility in physiologically relevant conditions are currently lacking. To address this, we developed a synthetic synovial fluid (SSF2) model and validated this model by investigating growth, aggregate formation, and antimicrobial susceptibility using multiple PJI isolates belonging to various microorganisms. In this study, 18 PJI isolates were included belonging to Staphylococcus aureus, coagulase-negative staphylococci, Cutibacterium acnes, Streptococcus spp., Enterococcus spp., Pseudomonas aeruginosa, Escherichia coli, and Candida spp. Growth and aggregate formation in SSF2 were evaluated using light microscopy and confocal laser scanning microscopy. The biofilm preventing concentration (BPC) and minimal biofilm inhibitory concentration (MBIC) of relevant antibiotics were determined using a resazurin-based viability staining. BPC and MBIC values were compared to conventional susceptibility parameters (minimal inhibitory concentration and minimal bactericidal concentration) determined with conventional approaches. The SSF2 medium allowed isolates to grow and form biofilm-like aggregates varying in size and shape between different species. For most isolates cultured in SSF2, a reduced susceptibility to the tested antibiotics was observed when compared to susceptibility data obtained in general media. These data indicate that the in vitro SSF2 model could be a valuable addition to evaluate the antimicrobial susceptibility of biofilm-like aggregates in the context of PJI.<br><br>IMPORTANCE: Infections after joint replacement are rare but can lead to severe complications as they are difficult to treat due to the ability of pathogens to form surface-attached biofilms on the prosthesis as well as biofilm aggregates in the tissue and synovial fluid. This biofilm phenotype, combined with the microenvironment at the infection site, substantially increases antimicrobial tolerance. Conventional in vitro models typically use standard growth media, which do not consider the microenvironment at the site of infection. By replacing these standard growth media with an in vivo-like medium, such as the synthetic synovial fluid medium, we hope to expand our knowledge on the aggregation of pathogens in the context of PJI. In addition, we believe that inclusion of in vivo-like media in antimicrobial susceptibility testing might be able to more accurately predict the in vivo susceptibility, which could ultimately result in a better clinical outcome after antimicrobial treatment.}, }
@article {pmid39611239, year = {2024}, author = {Wyatt, KH and Cieslik, J and Dieleman, CM and Kane, ES and Rober, AR and Sullivan, B and Turetsky, MR}, title = {Legacy Effects of Plant Community Structure Are Manifested in Microbial Biofilm Development With Consequences for Ecosystem CO2 Emissions.}, journal = {Global change biology}, volume = {30}, number = {12}, pages = {e17603}, pmid = {39611239}, issn = {1365-2486}, support = {1636476//Division of Environmental Biology/ ; 2011257//Division of Environmental Biology/ ; 2011286//Division of Environmental Biology/ ; 2141285//Division of Environmental Biology/ ; RJVA-PNW-01-JV-11261952-231//Pacific Northwest Research Station/ ; }, mesh = {*Carbon Dioxide/analysis/metabolism ; *Biofilms/growth &amp; development ; *Ecosystem ; Carbon Cycle ; Plants/microbiology ; Seasons ; Autotrophic Processes ; Groundwater/microbiology/chemistry ; Hydrology ; }, abstract = {To better understand linkages between hydrology and ecosystem carbon flux in northern aquatic ecosystems, we evaluated the relationship between plant communities, biofilm development, and carbon dioxide (CO2) exchange following long-term changes in hydrology in an Alaskan fen. We quantified seasonal variation in biofilm composition and CO2 exchange in response to lowered and raised water table position (relative to a control) during years with varying levels of background dissolved organic carbon (DOC). We then used nutrient-diffusing substrates (NDS) to evaluate cause-effect relationships between changes in plant subsidies (i.e., leachates) and biofilm composition among water table treatments. We found that background DOC concentration determined whether plant subsidies promoted net autotrophy or heterotrophy on NDS. In conditions where background DOC was ≤ 40 mg L[-1], plant subsidies promoted an autotrophic biofilm. Conversely, when background DOC concentration was ≥ 50 mg L[-1], plant subsidies promoted heterotrophy. Greater light attenuation associated with elevated levels of DOC may have overwhelmed the stimulatory effect of nutrients on autotrophic microbes by constraining photosynthesis while simultaneously allowing heterotrophs to outcompete autotrophs for available nutrients. At the ecosystem level, conditions that favored an autotrophic biofilm resulted in net CO2 uptake among all water table treatments, whereas the site was a net source of CO2 to the atmosphere in conditions that supported greater heterotrophy. Taken together, these findings show that hydrologic history interacts with changes in dominant plant functional groups to alter biofilm composition, which has consequences for ecosystem CO2 exchange.}, }
@article {pmid39610831, year = {2024}, author = {Willett, MR and Codd, SL and Seymour, JD and Kirkland, CM}, title = {Relaxation-weighted MRI analysis of biofilm EPS: Differentiating biopolymers, cells, and water.}, journal = {Biofilm}, volume = {8}, number = {}, pages = {100235}, pmid = {39610831}, issn = {2590-2075}, abstract = {Biofilms are a highly complex community of microorganisms embedded in a protective extracellular polymeric substance (EPS). Successful biofilm control requires a variety of approaches to better understand the structure-function relationship of the EPS matrix. Magnetic resonance imaging (MRI) is a versatile tool which can measure spatial structure, diffusion, and flow velocities in three dimensions and in situ. It is well-suited to characterize biofilms under natural conditions and at different length scales. MRI contrast is dictated by T 1 and T 2 relaxation times which vary spatially depending on the local chemical and physical environment of the sample. Previous studies have demonstrated that MRI can provide important insights into the internal structure of biofilms, but the contribution of major biofilm components-such as proteins, polysaccharides, and cells-to MRI contrast is not fully understood. This study explores how these components affect contrast in T 1 -and T 2 -weighted MRI by analyzing artificial biofilms with well-defined properties modeled after aerobic granular sludge (AGS), compact spherical biofilm aggregates used in wastewater treatment. MRI of these biofilm models showed that certain gel-forming polysaccharides are a major source of T 2 contrast, while other polysaccharides show minimal contrast. Proteins were found to reduce T 2 contrast slightly when combined with polysaccharides, while cells had a negligible impact on T 2 but showed T 1 contrast. Patterns observed in the model biofilms served as a reference for examining T 2 and T 1 -weighted contrast in the void spaces of two distinct AGS granules, allowing for a qualitative evaluation of the EPS components which may be present. Further insights provided by MRI may help improve understanding of the biofilm matrix and guide how to better manage biofilms in wastewater, clinical, and industrial settings.}, }
@article {pmid39610010, year = {2024}, author = {Bertl, K and Al-Said, M and Mourad, A and Mayol, M and Lopes da Silva, Z and Papia, E and Stavropoulos, A}, title = {Reduced Biofilm Accumulation on Implants Treated With Implantoplasty-An In Situ Trial With a Within-Subject Comparison.}, journal = {Clinical and experimental dental research}, volume = {10}, number = {6}, pages = {e70043}, pmid = {39610010}, issn = {2057-4347}, support = {//This study was funded by the authors' institutions./ ; }, mesh = {Humans ; *Biofilms ; Male ; Female ; *Dental Implants/microbiology ; Adult ; *Surface Properties ; Titanium ; Middle Aged ; Young Adult ; Dental Prosthesis Design ; }, abstract = {OBJECTIVES: This study aimed to evaluate potential differences in biofilm accumulation on three different implant surfaces: turned surface (TS), modified surface (MS), and modified surface treated with implantoplasty (IPS), using a within-subject comparison.<br><br>MATERIAL AND METHODS: Ten volunteers wore individualized splints containing three titanium implants with different surfaces (TS, MS, and IPS) on each buccal side of the splint. The implant position (anterior, central, and posterior) was randomly assigned among the three implants on each side. Volunteers were instructed to wear the splint for 72&#x2009;h and to remove it only for eating, drinking, and performing standard oral hygiene; the splint itself was not cleaned. After 72&#x2009;h, the implants were carefully removed from the splint, and the accumulated biofilm was assessed using a crystal violet assay by measuring intensity/absorbance at 570&#x2009;nm.<br><br>RESULTS: All volunteers reported no deviations from the instructions. The lowest mean amount of biofilm (0.405&#x2009;&#xb1;&#x2009;0.07) was detected on implants of the IPS group, followed by implants of the MS (0.463&#x2009;&#xb1;&#x2009;0.06) and TS group (0.467&#x2009;&#xb1;&#x2009;0.07). A multilevel mixed-effects linear regression analysis confirmed that implants of the IPS group accumulated a significantly lower amount of biofilm than the other surfaces (p&#x2009;<&#x2009;0.001); however, no significant difference was detected between implants of the TS and MS groups (p&#x2009;=&#x2009;0.806).<br><br>CONCLUSIONS: Implantoplasty can generate a surface significantly less conducive to biofilm accumulation in the short term compared to pristine implants with turned or modified surfaces.<br><br>TRIAL REGISTRATION: clinicaltrials.gov identifier: NCT06049121.}, }
@article {pmid39609958, year = {2024}, author = {Khursheed, H and Qasim, R}, title = {SYNERGISTIC ANTIBIOFILM ACTIVITY OF PROBIOTIC LACTOBACILLUS ACIDOPHILUS AND PUNICA GRANATUM L., AGAINST PSEUDOMONAS AERUGINOSA BIOFILM.}, journal = {Journal of Ayub Medical College, Abbottabad : JAMC}, volume = {36}, number = {2}, pages = {245-250}, doi = {10.55519/JAMC-02-12876}, pmid = {39609958}, issn = {1819-2718}, mesh = {*Biofilms/drug effects ; *Pseudomonas aeruginosa/drug effects ; *Lactobacillus acidophilus/drug effects/physiology ; *Pomegranate ; *Probiotics ; *Plant Extracts/pharmacology ; Humans ; Drug Synergism ; }, abstract = {BACKGROUND: Antibiotic resistance is one of the most urgent public health concerns. Biofilm formation is well linked with chronic wounds, chronic obstructive pulmonary disease, urinary tract infections, and cystic fibrosis. Our goal was to assess the biofilm activity of P. aeruginosa and the individual and combined anti-biofilm forming activity of probiotic Lactobacillus acidophilus and Pomegranate peel extract Punica granatum L., against P. aeruginosa.<br><br>METHODS: A total of 150 swabs of urine, blood, pus, and CSF were collected from PNS Shifa Hospital Karachi, and P. aeruginosa was isolated and identified according to standard bacteriological methods. The ability of P. aeruginosa to form biofilms was assessed using a microtiter plate assay.<br><br>RESULTS: The anti-biofilm forming activity of pomegranate peels extract against P. aeruginosa was 29.26&#xb1;19.09 whereas the anti-biofilm forming activity of Lactobacillus acidophilus against P. aeruginosa was 0.5&#xd7;106. When used in combination, there was significant synergistic activity between Punica granatum L. (pomegranate peel extract) and Lactobacillus acidophilus.<br><br>CONCLUSIONS: The unique synergistic mixture of natural product extracts and probiotics has demonstrated more efficiency against rapidly evolving pathogens, serving as promising candidates for developing biofilm inhibitors and perhaps proving as possible environmentally friendly agents against bacteria that produce antibiotic-resistant biofilms.}, }
@article {pmid39609837, year = {2024}, author = {Zhang, HL and Wang, HW and Yang, JH and Chen, JJ and Liu, J and Shi, QC and Zhao, HC and Chen, MX and Yang, R and Ji, QT and Wang, PY}, title = {From dansyl-modified biofilm disruptors to β-cyclodextrin-optimized multifunctional supramolecular nanovesicles: their improved treatment for plant bacterial diseases.}, journal = {Journal of nanobiotechnology}, volume = {22}, number = {1}, pages = {739}, pmid = {39609837}, issn = {1477-3155}, support = {2022YFD1700300//National Key Research and Development Program/ ; No. GCC[2023]008//Innovation Program for High-level Talents of Guizhou Province/ ; ZK[2022]017//Guizhou Provincial S&amp;T Project/ ; Guidakechuangtuan[2023]03//Research and Innovation Team of Guizhou University/ ; Guidazhuanjihe[2024]02//Natural Science Special Project of Guizhou University/ ; Qiankehezhongyindi (2023) 001//Central Government Guides Local Science and Technology Development Fund Projects/ ; 111 Program, D20023//Program of Introducing Talents of Discipline to Universities of China/ ; }, mesh = {*Biofilms/drug effects ; *Plant Diseases/microbiology/prevention &amp; control ; *beta-Cyclodextrins/chemistry ; *Xanthomonas/drug effects ; Anti-Bacterial Agents/pharmacology/chemistry ; Dansyl Compounds/chemistry/pharmacology ; Nanoparticles/chemistry ; Citrus/chemistry ; }, abstract = {BACKGROUND: Bacterial diseases caused by phytopathogenic Xanthomonas pose a significant threat to global agricultural production, causing substantial economic losses. Biofilm formation by these bacteria enhances their resistance to environmental stressors and chemical treatments, complicating disease control. The key to overcoming this challenge lies in the development of multifunctional green bactericides capable of effectively breaking down biofilm barriers, improving foliar deposition properties, and achieving the control of bacterial diseases.<br><br>RESULTS: We have developed a kind of innovative green bactericide from small-molecule conception to eco-friendly supramolecular nanovesicles (DaPA8@&#x3b2; -CD) by host-guest supramolecular technology. These nanoscale assemblies demonstrated the ability to inhibit and eradicate biofilm formation, while also promoted foliar wetting and effective deposition properties, laying the foundation for improving agrochemical utilization. Studies revealed that DaPA8@&#x3b2; -CD exhibited significant biofilm inhibition (78.66% at 7.0 &#xb5; g mL[-&#x2009;1]) and eradication (83.50% at 25.0 &#xb5; g mL[-&#x2009;1]), outperforming DaPA8 alone (inhibition: 59.71%, eradication: 66.79%). These nanovesicles also reduced exopolysaccharide formation and bacterial virulence. In vivo experiments showed enhanced control efficiency against citrus bacterial canker (protective: 78.04%, curative: 50.80%) at a low dose of 200 &#xb5; g mL[-&#x2009;1], superior to thiodiazole-copper-20%SC and DaPA8 itself.<br><br>CONCLUSION: This study demonstrates the potential of DaPA8@&#x3b2; -CD nanovesicles as multifunctional bactericides for managing Xanthomonas -induced plant diseases, highlighting the advantages of using host-guest supramolecular technology to enhance agrochemical bioavailability.}, }
@article {pmid39608581, year = {2025}, author = {Werneburg, GT and Vasavada, SP and Miller, AW}, title = {Reply to Editorial Comment on "Indwelling Urological Device Biofilm Composition and Characteristics in the Presence and Absence of Infection".}, journal = {Urology}, volume = {196}, number = {}, pages = {91-92}, doi = {10.1016/j.urology.2024.11.049}, pmid = {39608581}, issn = {1527-9995}, }
@article {pmid39608508, year = {2025}, author = {Xu, S and Feng, Y and Li, H and Huang, H and Chen, Q and Zhu, B and Liu, A and Xu, Y and Jin, X and Gui, S and Lu, X}, title = {Natural TPs inhibit biofilm formation by Multidrug-resistant Acinetobacter baumannii and biofilm-induced pulmonary inflammation.}, journal = {Microbial pathogenesis}, volume = {198}, number = {}, pages = {107172}, doi = {10.1016/j.micpath.2024.107172}, pmid = {39608508}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Acinetobacter baumannii/drug effects ; Animals ; *Drug Resistance, Multiple, Bacterial/drug effects ; Rats ; *Acinetobacter Infections/drug therapy/microbiology ; *Anti-Bacterial Agents/pharmacology ; *Pneumonia/drug therapy/microbiology ; Disease Models, Animal ; Rats, Sprague-Dawley ; Male ; Anti-Inflammatory Agents/pharmacology ; Microbial Sensitivity Tests ; NF-kappa B/metabolism ; Humans ; Signal Transduction/drug effects ; }, abstract = {Multidrug-resistant Acinetobacter baumannii (MDRAB) infections cause elevated rates of patient deaths in intensive care units owing to the high antibiotic resistance of the clinical isolates. The advent of multidrug-resistant A. baumannii (MDRAB) strains and the formation of their biofilms are cause for concern. Tea polyphenols (TPs), which exhibit antimicrobial activity, is an ideal alternative strategy for lowering the incidence of nosocomial bacterial infections. This study was conducted to determine the effects of TPs on MDRAB. The antimicrobial and anti-biofilm activities of TPs against MDRAB were investigated in vitro using the propidium iodide assay, scanning electron microscopy, transmission electron microscopy, crystalline violet staining and real-time quantitative PCR (qPCR). The in vivo anti-biofilm and anti-inflammatory effects of TPs were studied using a rat model of MDRAB biofilm-induced pulmonary inflammation. TPs effectively inhibited the proliferation of MDRAB and damaged its cell membrane. Additionally, they inhibited MDRAB biofilm formation by reducing the content of microbial extracellular polymeric substances and altering the expression of genes related to biofilm formation. Moreover, TPs reduced pathological features of lung injury and alleviated MDRAB biofilm-induced pneumonia in rats with a tracheal cannula, attenuating the inflammatory response by inhibiting NF-κB signaling. Our findings suggest that the anti-biofilm and anti-inflammatory activities of TPs render these naturally active compounds favorable candidates for the treatment of tracheal catheter-related infections.}, }
@article {pmid39608432, year = {2025}, author = {Wang, B and Ma, P and Liu, M and Huang, R and Qiu, Z and Pan, L and Wang, J and Liu, Y and Zhang, Q}, title = {Enhancement of microalgae co-cultivation self-settling performance and water purificationcapacity of microalgae biofilm.}, journal = {Environmental research}, volume = {265}, number = {}, pages = {120342}, doi = {10.1016/j.envres.2024.120342}, pmid = {39608432}, issn = {1096-0953}, mesh = {*Microalgae/growth &amp; development ; *Biofilms ; Aquaculture/methods ; Waste Disposal, Fluid/methods ; Wastewater/chemistry/microbiology ; Water Pollutants, Chemical ; Coculture Techniques ; Nitrogen/metabolism ; Water Purification/methods ; Chlorella/growth &amp; development ; Biomass ; }, abstract = {Cultivating microalgae for the remediation of aquaculture wastewater provides a promising solution for pollution control. However, the economic viability of this approach faces challenges due to the high costs associated with microalgal biomass harvesting. This study aims to address this issue by immobilizing microalgae onto coral velvet carriers, enhancing the efficiency of biomass recovery. Four types of microalgae were screened: Chlorella sp., Isochrysis galbana, Chaetoceros sp., and Nannochloropsis sp. Among them, Isochrysis galbana exhibited the best self sedimentation rate, achieving a self sedimentation rate of 94.36%. Chlorella sp. demonstrated the best denitrification rate, with a nitrate removal rate of 100% and an inorganic nitrogen removal rate of 79.13%. In addition, this study found that extracellular polymeric substances(EPS) affects the self-settling performance of microalgae, and the results emphasize the key role of tightly-bound EPS(TB-EPS) content in determining self settling efficiency. Furthermore,the assessments of the purification of simulated aquaculture wastewater were conducted, comparing the outcomes of co-cultivation with mono-culture. The co-cultivation strategy showed exceptional efficacy, achieving a 100% removal rate for NO3[-]-N by the 5th day. In contrast, mono-cultures of Chlorella sp. and Isochrysis galbana showed removal rates of 77.76% and 45.72%, respectively, at the same interval. Applying of the co-cultivation microalgal biofilm to treat the actual aquaculture wastewater showed remarkable denitrification performance, attaining a 100% removal rate for NO3[-]-N by the 7th day. The study proposes the co-cultivation of Chlorella sp. and Isochrysis galbana for treating aquaculture wastewater and explores the potential application of immobilization technology to remove nitrogen-containing pollutants.}, }
@article {pmid39606745, year = {2024}, author = {Muturi, P and Wachira, P and Wagacha, M and Mbae, C and Kavai, SM and Mugo, MM and Mohamed, M and González, JF and Kariuki, S and Gunn, JS}, title = {Salmonella Typhi Haplotype 58 biofilm formation and genetic variation in isolates from typhoid fever patients with gallstones in an endemic setting in Kenya.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1468866}, pmid = {39606745}, issn = {2235-2988}, support = {R01 AI099525/AI/NIAID NIH HHS/United States ; R01 AI116917/AI/NIAID NIH HHS/United States ; }, mesh = {*Salmonella typhi/genetics/isolation &amp; purification/drug effects ; Humans ; *Biofilms/growth &amp; development ; *Typhoid Fever/microbiology/epidemiology ; Kenya ; *Genetic Variation ; *Gallstones/microbiology/complications ; Haplotypes ; Whole Genome Sequencing ; Anti-Bacterial Agents/pharmacology ; Genotype ; Feces/microbiology ; Male ; Endemic Diseases ; Female ; Adult ; Carrier State/microbiology ; }, abstract = {Although typhoid fever has largely been eliminated in high-income countries, it remains a major global public health concern especially among low- and middle-income countries. The causative agent, Salmonella enterica serovar Typhi (S. Typhi), is a human restricted pathogen with a limited capacity to replicate outside the human host. Human carriers, 90% of whom have gallstones in their gallbladder, continue to shed the pathogen for an ill-defined period of time after treatment. The genetic mechanisms involved in establishing the carrier state are poorly understood, but S. Typhi is thought to undergo specific genetic changes within the gallbladder as an adaptive mechanism. In the current study, we aimed to identify the genetic differences in longitudinal clinical S. Typhi isolates from asymptomatic carriers with gallstones in a typhoid endemic setting in Nairobi, Kenya. Whole-genome sequences were analyzed from 22 S. Typhi isolates, 20 from stool samples, and 2 from blood samples, all genotype 4.3.1 (H58). Out of this, 19 strains were from four patients also diagnosed with gallstones, of whom three had typhoid symptoms and continued to shed S. Typhi after treatment. All isolates had point mutations in the quinolone resistance-determining region (QRDR), and only sub-lineage 4.3.1.2.EA3 encoded multidrug resistance genes. There was no variation in antimicrobial resistance patterns among strains from the same patient/household. Non-multidrug resistant (MDR) isolates formed significantly stronger biofilms in vitro than the MDR isolates, p<0.001. A point mutation within the treB gene (treB A383T) was observed in strains isolated after clinical resolution from patients living in 75% of the households. For missense mutations in Vi capsular polysaccharide genes, tviE P263S was also observed in 18% of the isolates. This study provides insights into the role of typhoid carriage, biofilm formation, AMR genes, and genetic variations in S. Typhi during asymptomatic carriage.}, }
@article {pmid39605964, year = {2024}, author = {Jia, J and Liu, Q and Zhao, E and Li, X and Xiong, X and Wu, C}, title = {Biofilm formation on microplastics and interactions with antibiotics, antibiotic resistance genes and pathogens in aquatic environment.}, journal = {Eco-Environment &amp; Health}, volume = {3}, number = {4}, pages = {516-528}, pmid = {39605964}, issn = {2772-9850}, abstract = {Microplastics (MPs) in aquatic environments easily support biofilm development, which can interact with other environmental pollutants and act as harbors for microorganisms. Recently, numerous studies have investigated the fate and behavior of MP biofilms in aquatic environments, highlighting their roles in the spread of pathogens and antibiotic resistance genes (ARGs) to aquatic organisms and new habitats. The prevalence and effects of MP biofilms in aquatic environments have been extensively investigated in recent decades, and their behaviors in aquatic environments need to be synthesized systematically with updated information. This review aims to reveal the development of MP biofilm and its interactions with antibiotics, ARGs, and pathogens in aquatic environments. Recent research has shown that the adsorption capabilities of MPs to antibiotics are enhanced after the biofilm formation, and the adsorption of biofilms to antibiotics is biased towards chemisorption. ARGs and microorganisms, especially pathogens, are selectively enriched in biofilms and significantly different from those in surrounding waters. MP biofilm promotes the propagation of ARGs through horizontal gene transfer (HGT) and vertical gene transfer (VGT) and induces the emergence of antibiotic-resistant pathogens, resulting in increased threats to aquatic ecosystems and human health. Some future research needs and strategies in this review are also proposed to better understand the antibiotic resistance induced by MP biofilms in aquatic environments.}, }
@article {pmid39604799, year = {2025}, author = {Li, B and Xu, Z and Wang, R and Nie, R and Tao, Z and Huang, X}, title = {Mineralizing Biofilm towards Sustainable Conversion of Plastic Wastes to Hydrogen.}, journal = {Angewandte Chemie (International ed. in English)}, volume = {64}, number = {4}, pages = {e202416577}, doi = {10.1002/anie.202416577}, pmid = {39604799}, issn = {1521-3773}, support = {22171058//National Natural Science Foundation of China/ ; 22475056//National Natural Science Foundation of China/ ; HIT.OCEF.2023040//Fundamental Research Funds for the Central Universities/ ; M-0470//China German Mobility Programme/ ; }, mesh = {*Biofilms ; *Hydrogen/chemistry/metabolism ; *Shewanella/metabolism ; *Plastics/chemistry/metabolism ; Polyesters/chemistry/metabolism ; }, abstract = {The integration of inorganic materials with biological machinery to convert plastics into fuels offers a promising strategy to alleviate environmental pollution and energy crisis. Herein, we develop a type of hybrid living material via biomineralization of CdS onto Shewanella oneidensis-based biofilm, which is capable of sustainable hydrogen production from poly(lactic acid) (PLA) wastes under daylight. We reveal that the formed biofilm microstructure provides an independent anaerobic microenvironment that simultaneously supports cellular viability, maintains hydrogenase activity, and preserves the functional stability of CdS, giving rise to the efficient plastic-to-hydrogen conversion efficiency as high as 3751 μmol H2 g-1 PLA. Besides, by genetically engineering transmembrane pili conduit and incorporating conductive nanomaterials to strengthen the electron transfer across cellular interface and biofilm matrices, we show that the conversion efficiency is further enhanced to 5862 μmol H2 g-1 PLA. Significantly, we exhibit that a long-term sustainable plastic-to-hydrogen conversion of 63 d could be achieved by periodically replenishing PLA wastes. Overall, by the synergistic integration of biotic-abiotic characteristics the developed biofilm-based biomineralized hybrid living material is anticipated to provide a new platform toward the efficient conversion of plastic wastes into valuable fuels, and bridge the gap between environmental contamination and green energy production.}, }
@article {pmid39604718, year = {2024}, author = {de Oliveira, RS and Gonçalves, AR and Ajulo, AA and Oliveira, LR and Lanna, AC and de Filippi, MCC}, title = {Survey and genomic characterization of Serratia marcescens on endophytism, biofilm, and phosphorus solubilization in rice plants.}, journal = {Environmental science and pollution research international}, volume = {31}, number = {57}, pages = {65834-65848}, pmid = {39604718}, issn = {1614-7499}, support = {20.19.03.012.00.00//Empresa Brasileira de Pesquisa Agropecu&#xe1;ria/ ; }, mesh = {*Oryza/microbiology ; *Phosphorus ; *Biofilms ; *Serratia marcescens/genetics/physiology ; Rhizosphere ; Endophytes/physiology ; Soil Microbiology ; Plant Roots/microbiology ; }, abstract = {Serratia marcescens, isolated from the rhizosphere of rice crops, has the potential to improve the acquisition of scarce minerals and provide plant growth. Rice seeds microbiolized with S. marcescens and non-microbiolized seeds were sown in a culture medium enriched with non-labile phosphorus, and the roots were analyzed in WinRhizo. The plant segments were documented by scanning electron microscopy (SEM) and incubated in an NBRIP culture medium. DNAs from endophytic colonies were extracted and analyzed by PCR. The genome of S. marcescens was annotated using subsystem technology to detect genes involved in phosphorus solubilization, biofilm production, and growth promotion. The root system increased in area, volume, and length by 61.5, 31.5, and 101%, respectively. Halos were formed around segments of microbiolized plants, indicating the solubilization of non-labile phosphorus. SEM detected the presence of biofilms and microcolonies, identified as S. marcescens by the molecular markers. Genome annotation found genes with potential functions in plant growth promotion, including genes involved in the biosynthesis of indole-3-acetic acid, phosphate solubilization, and biofilm production. In the low phosphorus crop, the treated plants showed a 181% increase in total biomass. S. marcescens solubilizes non-labile phosphorus, colonizes endophytes, modifies the architecture of the root system, and promotes the growth of rice plants, and can be considered a biofertilizer for growing upland rice.}, }
@article {pmid39604369, year = {2024}, author = {Li, M and Zeng, Z and Wang, X and Liu, Y and Wei, H and Liu, J and Zhu, S and Jiang, Q and Zhang, K and Wu, Y and Liu, S and Kim, J and Liao, Q and Zhang, L}, title = {Mechanisms of S. agalactiae promoting G. vaginalis biofilm formation leading to recurrence of BV.}, journal = {NPJ biofilms and microbiomes}, volume = {10}, number = {1}, pages = {138}, pmid = {39604369}, issn = {2055-5008}, support = {61927819//National Natural Science Foundation of China (National Science Foundation of China)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Streptococcus agalactiae/genetics/physiology ; *Carbon-Sulfur Lyases/genetics/metabolism ; Humans ; *Bacterial Proteins/genetics/metabolism ; *Coculture Techniques ; Female ; *Gardnerella vaginalis/genetics/physiology ; *Vaginosis, Bacterial/microbiology ; *Homoserine/analogs &amp; derivatives/metabolism ; Recurrence ; Lactones/metabolism ; Gene Expression Regulation, Bacterial ; Microbial Interactions ; }, abstract = {Previous research has established that the formation of Gardnerella vaginalis (GV) biofilm is one of the primary reasons for bacterial vaginosis (BV) recurrence. This study was the first to explore the impact of Streptococcus agalactiae (group B Streptococcus, GBS) on GV biofilm in a co-culture scenario. The results revealed that GBS could significantly increased the GV biomass in 48-hours dual-species biofilms. The luxS gene of GBS was significantly higher in dual-species biofilm, while knockdown of the luxS gene resulted in a significant decrease in mono- and dual-species biofilms. Meanwhile, in vitro addition of AI-2 (product of luxS gene) substantially increased biofilm biomass. Furthermore, we found that the expression of two genes related to biofilm formation was notably elevated in GV after receiving AI-2 signals. Collectively, these findings suggest that GBS enhances GV biofilm formation via luxS/AI-2 in an in vitro co-culture model, which in turn may promotes recurrence of BV.}, }
@article {pmid39603219, year = {2024}, author = {Ijzerman, MM and Raby, M and Letwin, NV and Black, T and Kudla, YM and Osborne, RK and Sibley, PK and Prosser, RS}, title = {Pesticide presence in stream water, suspended sediment and biofilm is strongly linked to upstream catchment land use and crop type.}, journal = {Ecotoxicology and environmental safety}, volume = {288}, number = {}, pages = {117382}, doi = {10.1016/j.ecoenv.2024.117382}, pmid = {39603219}, issn = {1090-2414}, mesh = {*Pesticides/analysis ; *Geologic Sediments/chemistry ; *Water Pollutants, Chemical/analysis ; *Biofilms ; *Rivers/chemistry/microbiology ; *Environmental Monitoring/methods ; Ontario ; *Agriculture ; Crops, Agricultural ; }, abstract = {Pesticide pollution can present high ecological risks to aquatic ecosystems. Small streams are particularly susceptible. There is a need for reproducible and readily available methods to identify aquatic regions at risk of pesticide contamination. There is currently a limited understanding of the relationship between upstream catchment land use and the presence of pesticides in multiple aquatic matrices. The aim of this study was to develop empirical relationships between different land uses and the levels of pesticides detected in multiple aquatic matrices. The inclusion of biofilm and suspended sediment as monitoring matrices has recently been proven effective for the characterization of pesticide exposure in stream ecosystems. Ten streams in Ontario, Canada with a variety of upstream catchment land uses were sampled in 2021 and 2022. Water, suspended sediment and biofilm were collected and analyzed from each site for the presence of approximately 500 different pesticides. Each of the three matrices exhibited distinctive pesticide exposure profiles. We found a significant relationship between the percentage of agriculture and urban land use and the detection of multiple pesticides in water, sediment and biofilm (logistic regressions, P<0.05). Statistically significant probabilistic models capable of predicting pesticide detections based on upstream catchment land use were developed. High-resolution cover crop maps identified soybeans, corn and other agriculture (e.g., vegetables, berries, canola) as the key variables associated with individual pesticide detection frequencies in each of the three matrices (linear regressions, P<0.05). Soybean land use was also the strongest predictor of site-wide pesticide pollution. This modelling approach using upstream catchment land use variables has the potential to be a powerful tool to identify streams at risk of pesticide pollution.}, }
@article {pmid39602230, year = {2024}, author = {Millot, M and Imbert, C and Pouget, C and Girardot, M and Mambu, L}, title = {Lichen and Its Microbiome as an Untapped Source of Anti-Biofilm Compounds.}, journal = {Chemistry &amp; biodiversity}, volume = {}, number = {}, pages = {e202401557}, doi = {10.1002/cbdv.202401557}, pmid = {39602230}, issn = {1612-1880}, support = {ANR-17-CE35-0005//Agence Nationale de la Recherche/ ; }, abstract = {Lichen substances have been first described in the 1870s, and around 10 000 compounds have been isolated and characterized. Most of them have been evaluated for their activity on planktonic microorganisms (bacteria and fungi). More recently, microorganisms colonizing the lichen thallus have been isolated and identified using DNA sequencing, giving access to a wide diversity of culturable microorganisms. The increasing research in lichen-associated microbiomes in recent years has emphasized a wide range of metabolites as a potential source of bioactive compounds. In parallel, humans are facing microbial resistance to conventional antimicrobial drugs. One of the reasons is the biofilm lifestyle of microorganisms. Indeed, the aggregation of microbial communities inside biofilms is now well known and characterized, and some possible ways to fight and destroy biofilms are identified (quorum sensing inhibitors, etc.). The present review aims to summarize the anti-biofilm potential of lichen metabolites and those from their associated microorganisms (bacteria and/or fungi). Are the metabolites isolated from lichens and their associated fungi displaying any anti-biofilm activity? This literature synthesis highlights the metabolites of interest as new anti-biofilm drugs and shows the lack of current biological research dealing with biofilm and lichen metabolites. Acetone and ethyl acetate extracts are the most studied sources of anti-biofilm agents. Only two lichen metabolites, usnic acid and evernic acid, have been evaluated both as antifungal and antibacterial biofilm compounds. Terpenoids from lichens are still poorly explored for this activity.}, }
@article {pmid39600574, year = {2024}, author = {Gangwar, R and Salem, MM and Maurya, VK and Bekhit, MM and Singh, N and Amara, AAAF and Sahu, RK and Ibrahim, MA}, title = {Exploring time-killing and biofilm inhibition potential of bioactive proteins extracted from two varieties of Pleurotus ostreatus.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1456358}, pmid = {39600574}, issn = {1664-302X}, abstract = {INTRODUCTION: Dental caries, caused by oral microbial pathogens, are a global health concern, further exacerbated by the presence of methicillin-resistant Staphylococcus aureus (MRSA). Bioactive proteins and peptides (BAPs) exhibit potent antimicrobial properties, targeting multiple cellular mechanisms within pathogens, reducing the likelihood of resistance development. Given the antimicrobial potential of BAPs, this study aimed to compare the efficacy of BAPs extracted from cultivated (Pleurotus ostreatus, PoC) and wild (Pleurotus ostreatus, PoW) mushrooms against pathogens responsible for dental caries.<br><br>METHODS: BAPs were extracted from both PoC and PoW using a TCA-acetone method. Antimicrobial activities were tested against seven bacteria and one fungus using agar well diffusion and MIC determination. Antibiofilm activity was assessed via modified CV assay, while DPPH and erythrocyte lysis tests evaluated free radical scavenging.<br><br>RESULTS: PoC showed superior antimicrobial efficacy, with lower MIC and MBC values, and disrupted biofilm integrity at increasing concentrations. PoW exhibited better antioxidant activity with higher DPPH scavenging, though its antimicrobial efficacy was slightly lower than PoC.<br><br>DISCUSSION: Both PoC and PoW BAPs inhibited dental pathogens, with PoC showing stronger inhibition against MRSA and nystatin-resistant Candida albicans. This suggests BAPs may target additional cellular mechanisms beyond membranes, PBPs, and ergosterols. Despite PoW's stronger antioxidant properties, both BAPs had comparable antibiofilm activity. These findings suggest complementary actions of BAPs from PoC and PoW both, in treating dental caries, offering broad-spectrum antimicrobial and antioxidant benefits.}, }
@article {pmid39600232, year = {2025}, author = {Hurlow, J and Wolcott, RD and Bowler, PG}, title = {Clinical management of chronic wound infections: The battle against biofilm.}, journal = {Wound repair and regeneration : official publication of the Wound Healing Society [and] the European Tissue Repair Society}, volume = {33}, number = {1}, pages = {e13241}, doi = {10.1111/wrr.13241}, pmid = {39600232}, issn = {1524-475X}, mesh = {*Biofilms/drug effects ; Humans ; *Wound Infection/microbiology/therapy/drug therapy ; *Wound Healing ; *Debridement/methods ; Chronic Disease ; Bandages ; Anti-Bacterial Agents/therapeutic use ; }, abstract = {Bacteria constitute the most abundant life form on earth, of which the majority exist in a protective biofilm state. Since the 1980s, we have learned much about the role of biofilm in human chronic infections, with associated global healthcare costs recently estimated at ~$386 billion. Chronic wound infection is a prominent biofilm-induced condition that is characterised by persistent inflammation and associated host tissue destruction, and clinical signs that are distinct from signs of acute wound infection. Biofilm also enables greater tolerance to antimicrobial agents in chronic wound infections compared with acute wound infections. Given the difficulty in eliminating wound biofilm, a multi-targeted strategy (namely biofilm-based wound care) involving debridement and antimicrobial therapies were introduced and have been practiced since the early 2000s. More recently, acknowledgement of the speed at which biofilm can develop and hence quickly interfere with wound healing has highlighted the need for an early anti-biofilm strategy to combat biofilm before it takes control and prevents wound healing. This strategy, referred to as wound hygiene, involves multiple tools in combination (debridement, cleansing, and antimicrobial dressings) to maximise success in biofilm removal and encourage wound healing. This review is intended to highlight the issues and challenges associated with biofilm-induced chronic infections, and specifically address the challenges in chronic wound management, and tools required to combat biofilm and encourage wound healing.}, }
@article {pmid39599508, year = {2024}, author = {Taner, F and Baddal, B and Theodoridis, L and Petrovski, S}, title = {Biofilm Production in Intensive Care Units: Challenges and Implications.}, journal = {Pathogens (Basel, Switzerland)}, volume = {13}, number = {11}, pages = {}, pmid = {39599508}, issn = {2076-0817}, abstract = {The prevalence of infections amongst intensive care unit (ICU) patients is inevitably high, and the ICU is considered the epicenter for the spread of multidrug-resistant bacteria. Multiple studies have focused on the microbial diversity largely inhabiting ICUs that continues to flourish despite treatment with various antibiotics, investigating the factors that influence the spread of these pathogens, with the aim of implementing sufficient monitoring and infection control methods. Despite joint efforts from healthcare providers and policymakers, ICUs remain a hub for healthcare-associated infections. While persistence is a unique strategy used by these pathogens, multiple other factors can lead to persistent infections and antimicrobial tolerance in the ICU. Despite the recognition of the detrimental effects biofilm-producing pathogens have on ICU patients, overcoming biofilm formation in ICUs continues to be a challenge. This review focuses on various facets of ICUs that may contribute to and/or enhance biofilm production. A comprehensive survey of the literature reveals the apparent need for additional molecular studies to assist in understanding the relationship between biofilm regulation and the adaptive behavior of pathogens in the ICU environment. A better understanding of the interplay between biofilm production and antibiotic resistance within the environmental cues exhibited particularly by the ICU may also reveal ways to limit biofilm production and indivertibly control the spread of antibiotic-resistant pathogens in ICUs.}, }
@article {pmid39597869, year = {2024}, author = {Maris, M and Martu, MA and Maris, M and Martu, C and Anton, DM and Pacurar, M and Earar, K}, title = {Clinical and Microbiological Periodontal Biofilm Evaluation of Patients with Type I Diabetes.}, journal = {Journal of clinical medicine}, volume = {13}, number = {22}, pages = {}, pmid = {39597869}, issn = {2077-0383}, abstract = {Background/Objectives: The purpose of this study was to assess the microbial composition and density of subgingival plaque samples for periodontal pathogens while correlating the values with glycemic control levels via glycated hemoglobin (HbA1c), a type of hemoglobin that has chemically linked glucose, in type I diabetes individuals who will undergo complex oral rehabilitation through orthodontic treatment and implant surgery. Methods: A cohort of 42 adults with type I diabetes were included in this study. The subjects sustained a comprehensive periodontal clinical examination as well as microbiological assessments of their subgingival plaque samples through quantitative real-time PCR. The samples were collected from the two deepest pockets of each subject. Results: The highest number of periodontopathogenic bacteria was observed in the pockets of 5-7 mm. T. forsythia showed the highest prevalence (20.48%), with decreasing numbers as follows: T. denticola (13.31%), P. gingivalis (11.26%), A. actinomycetemcomitans (7%), and P. intermedia (4.9%). T. denticola and T. forsythia were significantly more commonly observed in individuals with elevated HbA1c serum levels. No correlation was observed between P. gingivalis, A. actinomycetemcomitans, P. intermedia presence, and the HbA1c value. Conclusions: Periodontopathogenic agents' presence in subgingival biofilm samples varied in accordance with the pocket probing depth and metabolic control of the diabetic individuals. In our study, the appearance of these periodontopathogenic agents was linked to lowered metabolic control in patients with type I diabetes mellitus.}, }
@article {pmid39597697, year = {2024}, author = {Nagy-Radványi, L and Ormai, E and Koloh, R and Ángyán, VD and Kocsis, B and Bencsik-Kerekes, E and Szabó, P and Csikós, E and Farkas, &#xc1; and Horváth, G and Kocsis, M and Balázs, VL}, title = {Biofilm Inhibition Activity of Fennel Honey, Fennel Essential Oil and Their Combination.}, journal = {Microorganisms}, volume = {12}, number = {11}, pages = {}, pmid = {39597697}, issn = {2076-2607}, support = {NKFIH PD 147156//Fund of National Research, Development and Innovation Office/ ; NKFIH PD 142122//Fund of National Research, Development and Innovation Office/ ; EK&#xd6;P-24-4-I-PTE-113//GYTK KA-2024- 05 and by University Research Scholarship Program of the Ministry for Culture and Innovation from the Source of the National Research, Development and Innovation Fund/ ; EK&#xd6;P-24-4-II-PTE-114//GYTK KA-2024- 05 and by University Research Scholarship Program of the Ministry for Culture and Innovation from the Source of the National Research, Development and Innovation Fund/ ; }, abstract = {The eradication of bacterial biofilms remains a persistent challenge in medicine, particularly because an increasing number of biofilms exhibit resistance to conventional antibiotics. This underscores the importance of searching for novel compounds that present antibacterial and biofilm inhibition activity. Various types of honey and essential oil were proven to be effective against a number of biofilm-forming bacterial strains. The current study demonstrated the effectiveness of the relatively unexplored fennel honey (FH), fennel essential oil (FEO), and their combination against biofilm-forming bacterial strains Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus, and Escherichia coli, with a series of in vitro experiments. The authenticity of FH and FEO was checked with light microscopy and gas chromatography-mass spectrometry, respectively. Minimum inhibitory concentrations were determined using the microdilution method, and antibiofilm activity was assessed with crystal violet assay. Structural changes in bacterial cells and biofilms, induced by the treatments, were monitored with scanning electron microscopy. FEO and FH inhibited the biofilm formation of each bacterial strain, with FEO being more effective compared to FH. Their combination was the most effective, with inhibitory rates ranging between 87 and 92%, depending on the bacterial strain. The most sensitive bacterium was E. coli, while P. aeruginosa was the most resistant. These results provide justification for the combined use of honey and essential oil to suppress bacterial biofilms and can serve as a starting point to develop an effective surface disinfectant with natural ingredients.}, }
@article {pmid39597686, year = {2024}, author = {Sebbane, N and Abramovitz, I and Kot-Limon, N and Steinberg, D}, title = {Mechanistic Insight into the Anti-Bacterial/Anti-Biofilm Effects of Low Chlorhexidine Concentrations on Enterococcus faecalis-In Vitro Study.}, journal = {Microorganisms}, volume = {12}, number = {11}, pages = {}, pmid = {39597686}, issn = {2076-2607}, abstract = {BACKGROUND: Endodontic treatment failures are often linked to the persistence of Enterococcus faecalis in the root canal system. This study aimed to investigate the antibacterial/antibiofilm mechanism of chlorhexidine (CHX), particularly at low concentrations, against E. faecalis, to improve endodontic treatment protocols.<br><br>METHODS: The antibacterial activity of CHX (0.125-20 &#x3bc;g/mL) was evaluated against E. faecalis ATCC 29212 using various assays, including planktonic growth inhibition, colony-forming units (CFUs), membrane permeability and potential assays, high-resolution scanning electron microscopy (HR-SEM), confocal laser scanning microscopy of biofilms, biomass and metabolic activity assays on matured biofilm, and quantitative real-time PCR for gene expression. Statistical analysis was performed using Student's t-test and ANOVA.<br><br>RESULTS: CHX demonstrated concentration-dependent inhibition of E. faecalis, significantly reducing planktonic growth and CFUs. Membrane assays showed increased permeability and depolarization, indicating damage. HR-SEM revealed morphological changes, such as pore formation, while confocal microscopy showed a reduction in biofilm mass and extracellular substances. Gene expression analysis indicated the downregulation of virulence genes and upregulation of stress response genes.<br><br>CONCLUSIONS: CHX at low concentrations disrupts E. faecalis at multiple levels, from membrane disruption to gene expression modulation, affecting mature biofilm. These findings support the refinement of endodontic disinfection protocols to reduce microbial persistence.}, }
@article {pmid39597673, year = {2024}, author = {Gallina, NLF and Irizarry Tardi, N and Li, X and Cai, A and Horn, MJ and Applegate, BM and Reddivari, L and Bhunia, AK}, title = {Assessment of Biofilm Formation and Anti-Inflammatory Response of a Probiotic Blend in a Cultured Canine Cell Model.}, journal = {Microorganisms}, volume = {12}, number = {11}, pages = {}, pmid = {39597673}, issn = {2076-2607}, support = {2021-38420-34058//USDA-NIFA/ ; 1016249//USDA-NIFA/ ; }, abstract = {Gut dysbiosis and an inflamed bowel are growing concerns in mammals, including dogs. Probiotic supplements have been used to restore the natural microbial community and improve gastrointestinal health. Biofilm formation, antimicrobial activities, and immunological responses of probiotics are crucial to improving gut health. Thus, we tested a commercial probiotic blend (LabMAX-3), a canine kibble additive comprising Lactobacillus acidophilus, Lacticaseibacillus casei, and Enterococcus faecium for their ability to inactivate common enteric pathogens; their ability to form biofilms; epithelial cell adhesion; and their anti-inflammatory response in the Madin-Darby Canine Kidney (MDCK) cell line. Probiotic LabMAX-3 blend or individual isolates showed a strong inhibitory effect against Salmonella enterica, Listeria monocytogenes, enterotoxigenic Escherichia coli, and Campylobacter jejuni. LabMAX-3 formed biofilms comparable to Staphylococcus aureus. LabMAX-3 adhesion to the MDCK cell line (with or without lipopolysaccharide (LPS) pretreatment) showed comparable adhesion and biofilm formation (p < 0.05) to L. casei ATCC 334 used as a control. LabMAX-3 had no cytotoxic effects on the MDCK cell line during 1 h exposure. The interleukin-10 (IL-10) and tumor necrosis factor alpha (TNFα) ratio of LabMAX-3, compared to the L. casei control, showed a significant increase (p < 0.05), indicating a more pronounced anti-inflammatory response. The data show that LabMAX-3, a canine kibble supplement, can improve gastrointestinal health.}, }
@article {pmid39597647, year = {2024}, author = {Niazy, AA and Alrashed, MM and Lambarte, RNA and Niazy, AA}, title = {5-Fluorouracil Inhibits Bacterial Growth and Reduces Biofilm in Addition to Having Synergetic Effects with Gentamicin Against Pseudomonas aeruginosa.}, journal = {Microorganisms}, volume = {12}, number = {11}, pages = {}, pmid = {39597647}, issn = {2076-2607}, abstract = {Pseudomonas aeruginosa is a multidrug-resistant pathogen known for chronic infections, mainly due to biofilm formation. This study aimed to explore the potential repurposing of 5-fluorouracil (5-FU), an anticancer drug, to treat P. aeruginosa infections. Firstly, we investigated the inhibitory effects of 5-FU on bacterial growth using the microdilution method. Secondly, the impact of 5-FU on biofilm formation and disassembly was assessed via biofilm biomass measurements with the crystal violet staining method and confocal microscopy analyses. Lastly, the potential synergy between 5-FU and the antibiotics gentamicin and meropenem was evaluated using a checkerboard assay. Results revealed that 5-FU inhibited bacterial growth in a dose-dependent manner, with 100% inhibition observed at concentrations of 25 µg/mL and higher. Also, 70% and 100% reductions in biofilm biomass were demonstrated at concentrations of 12 and 100 µg/mL, respectively. Controversy, these higher concentrations unexpectedly increased biofilm biomass in pre-formed biofilms. Synergistic interactions were observed between 5-FU and gentamicin in both growth inhibition (FICI 0.31) and biofilm inhibition (ZIP 14.1), while no synergy was found with meropenem. These findings highlight the potential of 5-FU as an adjunctive therapy for P. aeruginosa infections, especially in combination with gentamicin. However, further research is required to address 5-FU limitations against mature biofilms.}, }
@article {pmid39597626, year = {2024}, author = {Galelli, ME and Cristóbal-Miguez, JAE and Cárdenas-Aguiar, E and García, AR and Paz-González, A and Sarti, GC}, title = {The Effects of Seed Inoculation with Bacterial Biofilm on the Growth and Elemental Composition of Tomato (Solanum lycopersicum L.) Cultivated on a Zinc-Contaminated Substrate.}, journal = {Microorganisms}, volume = {12}, number = {11}, pages = {}, pmid = {39597626}, issn = {2076-2607}, abstract = {Biofilm obtained from Bacillus subtilis subsp. spizizenii inoculated on vegetable seeds has been shown to have plant growth-promoting capacity. Seed inoculation with biofilm produced by this strain could also reduce the adverse effects on plant growth caused by soil or substrate heavy metal overabundance. Therefore, the objective of this work was to evaluate the impact of biofilm inoculated on tomato (Solanum lycopersicum L.) seeds, which were planted on a substrate with artificially added zinc. First, seeds of the Río Grande tomato variety were exposed to increasing zinc concentrations, namely: 50, 100, 200, and 400 ppm, with and without bacterial biofilm inoculation. Zinc addition and seed inoculation affected germination parameters. For example, an extra 200 and 400 ppm of zinc led to high toxicity. Biofilm inoculation, however, reduced the noxious effects of excess zinc, bringing acute toxicity down to moderate. Then, tomato plants growing from inoculated and non-inoculated seeds were cropped for 4 months in both substrates with 400 ppm zinc and without added zinc. Extra zinc addition significantly (p < 0.05) reduced tomato root and shoot biomass, plant height, and fruit number at harvest time. However, seed biofilm inoculation avoided the harmful effect of zinc on plant growth parameters, fruit yield, and fruit quality. The roots and shoots of plants growing on contaminated substrates showed very noticeable increases in zinc levels compared to the control, while fruits only showed a much weaker zinc gain, even if this was significant (p < 0.05). Moreover, root shoot and fruit concentrations of elements other than zinc, (nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, iron, manganese, copper, lead, and cadmium) were not or only weakly affected by the addition of this metal to the substrate. In summary, the biofilm of B. subtilis proved to be effective as a bioinoculant to alleviate negative effects on tomatoes cropped in a substrate with excess zinc.}, }
@article {pmid39597620, year = {2024}, author = {Grzech-Leśniak, Z and Szwach, J and Lelonkiewicz, M and Migas, K and Pyrkosz, J and Szwajkowski, M and Kosidło, P and Pajączkowska, M and Wiench, R and Matys, J and Nowicka, J and Grzech-Leśniak, K}, title = {Effect of Nd:YAG Laser Irradiation on the Growth of Oral Biofilm.}, journal = {Microorganisms}, volume = {12}, number = {11}, pages = {}, pmid = {39597620}, issn = {2076-2607}, support = {SKN 255//Wroclaw Medical University/ ; }, abstract = {BACKGROUND: Oral microbiota comprises a wide variety of microorganisms. The purpose of this study was to evaluate the effects of Nd:YAG laser with a 1064 nm wavelength on the in vitro growth of Candida albicans, Candida glabrata, and Streptococcus mutans clinical strains, as well as their biofilm. The study also aimed to determine whether the parameters recommended for photobiomodulation (PBM) therapy, typically used for tissue wound healing, have any additional antibacterial or antifungal effects.<br><br>MATERIAL AND METHODS: Single- and dual-species planktonic cell solution and biofilm cultures of Streptococcus mutans, Candida albicans, and Candida glabrata were irradiated using an Nd:YAG laser (LightWalker; Fotona; Slovenia) with a flat-top Genova handpiece. Two test groups were evaluated: Group 1 (G-T1) exposed to low power associated parameters (irradiance 0.5 W/cm[2]) and Group 2 (G-T2) with higher laser parameters (irradiance 1.75 W/cm[2]). Group 3 (control) was not exposed to any irradiation. The lasers' effect was assessed both immediately after irradiation (DLI; Direct Laser Irradiation) and 24 h post-irradiation (24hLI) of the planktonic suspension using a quantitative method (colony-forming units per 1 mL of suspension; CFU/mL), and the results were compared with the control group, in which no laser was applied. The impact of laser irradiation on biofilm biomass was assessed immediately after laser irradiation using the crystal violet method.<br><br>RESULTS: Nd:YAG laser irradiation with photobiomodulation setting demonstrated an antimicrobial effect with the greatest immediate reduction observed in S. mutans, achieving up to 85.4% reduction at the T2 settings. However, the laser's effectiveness diminished after 24 h. In single biofilm cultures, the highest reductions were noted for C. albicans and S. mutans at the T2 settings, with C. albicans achieving a 92.6 &#xb1; 3.3% reduction and S. mutans reaching a 94.3 &#xb1; 5.0% reduction. Overall, the T2 settings resulted in greater microbial reductions compared to T1, particularly in biofilm cultures, although the effectiveness varied depending on the microorganism and culture type. Laser irradiation, assessed immediately after using the crystal violet method, showed the strongest biofilm reduction for Streptococcus mutans in the T2 settings for both single-species and dual-species biofilms, with higher reductions observed in all the microbial samples at the T2 laser parameters (p < 0.05) Conclusion: The Nd:YAG laser using standard parameters typically applied for wound healing and analgesic effects significantly reduced the number of Candida albicans; Candida glabrata; and Streptococcus mutans strains.}, }
@article {pmid39597612, year = {2024}, author = {Chen, R and Saint Bezard, J and Swann, MJ and Watson, F and Percival, SL}, title = {An In Vitro Artificial Wound Slough-Biofilm Model Developed for Evaluating a Novel Antibiofilm Technology.}, journal = {Microorganisms}, volume = {12}, number = {11}, pages = {}, pmid = {39597612}, issn = {2076-2607}, abstract = {Eschar and slough in wounds serve as a reservoir for microorganisms and biofilms, damaged/devitalised cells, and inflammatory chemokines/cytokines, which work to initiate and prolong persistent inflammation and increase the risk of infection. Biofilm-related inflammation and infections are considered to be highly prevalent in acute wounds and chronic wounds. As slough is known to harbour biofilms, measuring the efficacy of antimicrobials in killing microbes both within and under slough is warranted. This highlights the need for more clinically relevant wound biofilm models to address this significant clinical need. Consequently, in this study, we developed an in vitro artificial wound slough (AWS) biofilm model produced by forming a biofilm below a layer of AWS, the latter of which was composed of the main protein components reported in wound eschar and slough, namely collagen, elastin, and fibrin. The model was employed to investigate the antibiofilm and antibacterial efficacy of a new patented smart next-generation antibiofilm technology composed of silver-zinc EDTA complexes and designed as a family of multifunctional metal complexes referred to as MMCs, in a liquid format, and to determine both the performance and penetration through AWS to control and manage biofilms. The results demonstrated the ability of the AWS-biofilm model to be employed for the evaluation of the efficacy of a new antibiofilm and antimicrobial next-generation smart technology. The results also demonstrated the potential for the proprietary EDTA multifunctional metal complexes to be used for the disruption of biofilms, such as those that form in chronic wounds.}, }
@article {pmid39597514, year = {2024}, author = {Kostoglou, D and Apostolopoulou, M and Lagou, A and Didos, S and Argiriou, A and Giaouris, E}, title = {Investigating the Potential of L(+)-Lactic Acid as a Green Inhibitor and Eradicator of a Dual-Species Campylobacter spp. Biofilm Formed on Food Processing Model Surfaces.}, journal = {Microorganisms}, volume = {12}, number = {11}, pages = {}, pmid = {39597514}, issn = {2076-2607}, support = {5046750//EPAnEk-NRSF 2014-2020/ ; }, abstract = {Campylobacter spp. are prevalent foodborne bacterial enteric pathogens. Their inclusion in biofilms on abiotic surfaces is considered a strategy that facilitates their extraintestinal survival. Organic acid (OA) treatments could be used in a green approach to decontaminate various surfaces. This work aimed to evaluate the inhibitory and eradicative effects of L(+)-lactic acid (LA), a naturally occurring OA, on a dual-species biofilm formed on two food processing model surfaces (polystyrene and stainless steel) by three selected foodborne Campylobacter spp. isolates (two C. jejuni and one C. coli). The influence of aerobiosis conditions (microaerophilic, aerobic and CO2 enriched) on the resistance of the established biofilms to the acid was also tested. In parallel, the predominant metabolites contained in the planktonic media of biofilm monocultures and mixed-culture biofilm were comparatively analyzed by an untargeted metabolomics approach. Results revealed that LA inhibited mixed-culture biofilm formation by more than 2 logs (>99%) on both surfaces when this was applied at its highest tested concentration (4096 μg/mL; 0.34% v/v). However, all the preformed mixed-culture biofilms (ca. 10[6-7] CFU/cm[2]) could not be eradicated even when the acid was used at concentrations exceeding 5% v/v, denoting their extremely high recalcitrance which was still influenced by the abiotic substratum, and the biofilm-forming aerobiosis conditions. The metabolic analysis revealed a strain-specific metabolite production which might also be related to the strain-specific biofilm-forming and resistance behaviors and resulted in the distinct clustering of the different samples. Overall, the current findings provide important information on the effectiveness of LA against biofilm campylobacteria and may assist in mitigating their risk in the food chain.}, }
@article {pmid39597505, year = {2024}, author = {Høiby, N and Moser, C and Ciofu, O}, title = {Pseudomonas aeruginosa in the Frontline of the Greatest Challenge of Biofilm Infection-Its Tolerance to Antibiotics.}, journal = {Microorganisms}, volume = {12}, number = {11}, pages = {}, pmid = {39597505}, issn = {2076-2607}, abstract = {P. aeruginosa biofilms are aggregates of bacteria surrounded by a self-produced matrix which binds to some antibiotics such as aminoglycosides. P. aeruginosa biofilms are tolerant to antibiotics. The treatment of biofilm infections leads to a recurrence of symptoms after finishing antibiotic treatment, although the initial clinical response to the treatment is frequently favorable. There is a concentration gradient of oxygen and nutrients from the surface to the center of biofilms. Surface-located bacteria are multiplying and metabolizing, whereas deeper located bacteria are dormant and tolerant to most antibiotics. Colistin kills dormant bacteria, and combination therapy with colistin and antibiotics which kills multiplying bacteria is efficient in vitro. Some antibiotics such as imipenem induce additional production of the biofilm matrix and of chromosomal beta-lactamase in biofilms. Biofilms present a third Pharmacokinetic/Pharmacodynamic (PK/PD) micro-compartment (first: blood, second: tissue, third: biofilm) which must be taken into consideration when calculations try to predict the antibiotic concentrations in biofilms and thereby the probability of target attainment (PTA) for killing the biofilm. Treating biofilms with hyperbaric oxygen to wake up the dormant cells, destruction of the biofilm matrix, and the use of bacteriophage therapy in combination with antibiotics are promising possibilities which have shown proof of concept in in vitro experiments and in animal experiments.}, }
@article {pmid39596757, year = {2024}, author = {Grygiel, I and Bajrak, O and Wójcicki, M and Krusiec, K and Jończyk-Matysiak, E and Górski, A and Majewska, J and Letkiewicz, S}, title = {Comprehensive Approaches to Combatting Acinetobacter baumannii Biofilms: From Biofilm Structure to Phage-Based Therapies.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {11}, pages = {}, pmid = {39596757}, issn = {2079-6382}, abstract = {Acinetobacter baumannii-a multidrug-resistant (MDR) pathogen that causes, for example, skin and soft tissue wounds; urinary tract infections; pneumonia; bacteremia; and endocarditis, particularly due to its ability to form robust biofilms-poses a significant challenge in clinical settings. This structure protects the bacteria from immune responses and antibiotic treatments, making infections difficult to eradicate. Given the rise in antibiotic resistance, alternative therapeutic approaches are urgently needed. Bacteriophage-based strategies have emerged as a promising solution for combating A. baumannii biofilms. Phages, which are viruses that specifically infect bacteria, offer a targeted and effective means of disrupting biofilm and lysing bacterial cells. This review explores the current advancements in bacteriophage therapy, focusing on its potential for treating A. baumannii biofilm-related infections. We described the mechanisms by which phages interact with biofilms, the challenges in phage therapy implementation, and the strategies being developed to enhance its efficacy (phage cocktails, engineered phages, combination therapies with antibiotics). Understanding the role of bacteriophages in both biofilm disruption and in inhibition of its forming could pave the way for innovative treatments in combating MDR A. baumannii infections as well as the prevention of their development.}, }
@article {pmid39596741, year = {2024}, author = {Tortella Fuentes, G and Fincheira, P and Rubilar, O and Leiva, S and Fernandez, I and Schoebitz, M and Pelegrino, MT and Paganotti, A and Dos Reis, RA and Seabra, AB}, title = {Nanoparticle-Based Nitric Oxide Donors: Exploring Their Antimicrobial and Anti-Biofilm Capabilities.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {11}, pages = {}, pmid = {39596741}, issn = {2079-6382}, support = {220003/WT_/Wellcome Trust/United Kingdom ; }, abstract = {Background: Nitric oxide (NO) is an antimicrobial and anti-biofilm agent with significant potential for combating biofilm-associated infections and antibiotic resistance. However, owing to its high reactivity due to the possession of a free radical and short half-life (1-5 s), the practical application of NO in clinical settings is challenging. Objectives: This review explores the development of NO-releasing nanoparticles that provide a controlled, targeted delivery system for NO, enhancing its antimicrobial efficacy while minimizing toxicity. The review discusses various NO donors, nanoparticle platforms, and how NO disrupts biofilm formation and eradicates pathogens. Additionally, we examine the highly encouraging and inspiring results of NO-releasing nanoparticles against multidrug-resistant strains and their applications in medical and environmental contexts. This review highlights the promising role of NO-based nanotechnologies in overcoming the challenges posed by increasing antibiotic resistance and biofilm-associated infections. Conclusions: Although NO donors and nanoparticle delivery systems show great potential for antimicrobial and anti-biofilm uses, addressing challenges related to controlled release, toxicity, biofilm penetration, resistance, and clinical application is crucial.}, }
@article {pmid39596734, year = {2024}, author = {Avila-Novoa, MG and Solis-Velazquez, OA and Guerrero-Medina, PJ and Martínez-Chávez, L and Martínez-Gonzáles, NE and Gutiérrez-Lomelí, M}, title = {Listeria monocytogenes in Fruits and Vegetables: Antimicrobial Resistance, Biofilm, and Genomic Insights.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {11}, pages = {}, pmid = {39596734}, issn = {2079-6382}, abstract = {BACKGROUND/OBJECTIVES: Listeria monocytogenes is a foodborne pathogen that can infect both humans and animals and cause noninvasive gastrointestinal listeriosis or invasive listeriosis. The objectives of this study were to determine the genetic diversity of L. monocytogenes; the genes associated with its resistance to antibiotics, benzalkonium chloride (BC), and cadmium chloride (CdCl2); and its biofilm formation.<br><br>METHODS: A total of 132 fresh fruits (44 samples) and vegetables (88 samples) were selected for this study. The genetic diversity of the isolates and the genes associated with their antibiotic resistance were determined using PCR amplification; meanwhile, their levels of susceptibility to antibiotics were determined using the agar diffusion method. Their levels of resistance to BC and CdCl2 were determined using the minimum inhibitory concentration method, and their capacity for biofilm formation was evaluated using the crystal violet staining method.<br><br>RESULTS: A total of 17 L. monocytogenes strains were collected: 12.8% (17/132) from fresh fruits and vegetables in this study. The isolates of L. monocytogenes belonged to phylogenetic groups I.1 (29.4% (5/17); serotype 1/2a) and II.2 (70.5% (12/17); serotype 1/2b); strains containing Listeria pathogenicity islands (LIPIs) were also identified at prevalence rates of 100% for LIPI-1 and LIPI-2 (17/17), 29.4% for LIPI-3 (5/17), and 11.7% for LIPI-4 (2/17). The antibiotic susceptibility tests showed that the L. monocytogenes isolates exhibited six different multiresistant patterns, with multiple antibiotic resistance (MAR) index of &#x2265;0.46 (70.5%; 12/17); additionally, the genes Ide, tetM, and msrA, associated with efflux pump Lde, tetracycline, and ciprofloxacin resistance, were detected at 52.9% (9/17), 29.4% (5/17), and 17.6% (3/17), respectively. The phenotypic tests showed that 58.8% (10/17) of cadmium-resistant L. monocytogenes isolates had a co-resistance of 23.5% (4/17) to BC. Finally, all strains of L. monocytogenes exhibited moderate biofilm production.<br><br>CONCLUSIONS: The results of this study contribute to our understanding of the persistence and genetic diversity of L. monocytogenes strains isolated from fresh fruits and vegetables; in addition, their resistance to CdCl2, which is correlated with co-resistance to BC disinfectant, is helpful for the food industry.}, }
@article {pmid39596709, year = {2024}, author = {Lannes-Costa, PS and Fernandes, IR and Pena, JMS and Costa, BRFV and Cunha, MMLD and Ferreira-Carvalho, BT and Nagao, PE}, title = {Antibiotic Resistance and Presence of Persister Cells in the Biofilm-like Environments in Streptococcus agalactiae.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {11}, pages = {}, pmid = {39596709}, issn = {2079-6382}, support = {PDR10 E-26/204.521/ 2021//Funda&#xe7;&#xe3;o Carlos Chagas Filho de Amparo &#xe0; Pesquisa do Estado do Rio de Janeiro/ ; E-26/210.373/2024//Funda&#xe7;&#xe3;o Carlos Chagas Filho de Amparo &#xe0; Pesquisa do Estado do Rio de Janeiro/ ; PrInt 88887.3115972018-00//Coordena&#xe7;&#xe3;o de Aperfeicoamento de Pessoal de N&#xed;vel Superior/ ; Finance Code 001//Coordena&#xe7;&#xe3;o de Aperfeicoamento de Pessoal de N&#xed;vel Superior/ ; }, abstract = {Objectives: This study investigated antibiotic resistance and presence of persister cells in Streptococcus agalactiae strains belonging to capsular types Ia/ST-103, III/ST-17, and V/ST-26 in biofilm-like environments. Results: S. agalactiae strains were susceptible to penicillin, clindamycin, and erythromycin. Resistance genes were associated with tetM (80%), tetO (20%), ermB (80%), and linB (40%). Persister cells were detected in bacterial strains exposed to high concentrations of penicillin, clindamycin, and erythromycin. S. agalactiae capsular type III/ST-17 exhibited the highest percentage of persister cells in response to penicillin and clindamycin, while type Ia/ST-103 presented the lowest percentages of persister cells for all antimicrobials tested. Additionally, persister cells were also detected at lower levels for erythromycin, regardless of capsular type or sequence type. Further, all S. agalactiae isolates presented efflux pump activity in ethidium bromide-refractory cell assays. LIVE/DEAD fluorescence microscopy confirmed the presence of >85% viable persister cells after antibiotic treatment. Conclusions: These findings suggest that persister cells play a key role in the persistence of S. agalactiae during antibiotic therapy, interfering with the treatment of invasive infections. Monitoring persister formation is crucial for developing strategies to combat recurrent infections caused by this pathogen.}, }
@article {pmid39596695, year = {2024}, author = {Sánchez, MC and Hernández, P and Velapatiño, &#xc1; and Cuba, E and Ciudad, MJ and Collado, L}, title = {Illumina Sequencing in Conjunction with Propidium Monoazide to Identify Live Bacteria After Antiseptic Treatment in a Complex Oral Biofilm: A Study Using an Ex Vivo Supragingival Biofilm Model.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {11}, pages = {}, pmid = {39596695}, issn = {2079-6382}, abstract = {Background/Objectives: The evaluation of the efficacy of antibacterial treatments in complex oral ecosystems is limited by the inability to differentiate live from dead bacteria using omic techniques. The objective of this study was therefore to assess the ability of the combination of the 16S rRNA Illumina sequencing methodology and the action of propidium monoazide (PMA) to study viable bacterial profiles in oral biofilms after exposure to an antiseptic compound. Methods: Cariogenic supragingival biofilms were developed in an ex vivo model for 96 h, using saliva from healthy volunteers. The biofilms were treated with 0.12% chlorhexidine (CHX) combined with 0.05% cetylpyridinium chloride (CPC), for 60 s, using phosphate buffered saline as a control. After exposure, each biofilm was treated or not with PMA to then extract the bacterial DNA, quantify it by Qubit, quantify the bacterial population using qPCR, and perform the metataxonomic study of the samples using Illumina 16S rRNA sequencing. Results: A significantly lower DNA concentration in the PMA-treated biofilms (p < 0.05 compared with those not exposed to PMA) was observed. The viable bacterial count obtained by qPCR differed significantly from the total bacterial count in the biofilm samples exposed to the antiseptic (p < 0.05). The viable microbiome differed significantly from the total bacterial profile of the samples treated with CHX/CPC after exposure to PMA (p < 0.05 at the α- and β-diversity levels). Conclusions: The combination of Illumina 16S rRNA sequencing and PMA helps solve the inability to evaluate the efficacy of antibacterial treatments in the bacterial profile of complex ecosystems such as oral biofilms.}, }
@article {pmid39596287, year = {2024}, author = {Krzyżek, P}, title = {Helicobacter pylori Efflux Pumps: A Double-Edged Sword in Antibiotic Resistance and Biofilm Formation.}, journal = {International journal of molecular sciences}, volume = {25}, number = {22}, pages = {}, pmid = {39596287}, issn = {1422-0067}, mesh = {*Helicobacter pylori/drug effects/metabolism/genetics/physiology ; *Biofilms/drug effects/growth &amp; development ; *Anti-Bacterial Agents/pharmacology ; *Bacterial Proteins/metabolism/genetics ; *Membrane Transport Proteins/metabolism/genetics ; Humans ; Drug Resistance, Bacterial ; Helicobacter Infections/drug therapy/microbiology ; }, abstract = {Helicobacter pylori is a major pathogen associated with various gastric diseases. Despite decades of research, the treatment of H. pylori remains challenging. One of the primary mechanisms contributing to failures of therapies targeting this bacterium is genetic mutations in drug target sites, although the growing body of scientific data highlights that efflux pumps may also take part in this process. Efflux pumps are proteinaceous transporters actively expelling antimicrobial agents from the interior of the targeted cells and reducing the intracellular concentration of these compounds. Considering that efflux pumps contribute to both antimicrobial resistance and biofilm formation, an in-depth understanding of their properties may constitute a cornerstone in the development of novel therapeutics against H. pylori. In line with this, the aim of the current review is to describe the multitude of efflux pumps produced by H. pylori and present the data describing the involvement of these proteins in tolerance and/or resistance to various classes of antimicrobial substances.}, }
@article {pmid39596223, year = {2024}, author = {Phuengmaung, P and Chongrak, C and Saisorn, W and Makjaroen, J and Singkham-In, U and Leelahavanichkul, A}, title = {The Coexistence of Klebsiella pneumoniae and Candida albicans Enhanced Biofilm Thickness but Induced Less Severe Neutrophil Responses and Less Inflammation in Pneumonia Mice Than K. pneumoniae Alone.}, journal = {International journal of molecular sciences}, volume = {25}, number = {22}, pages = {}, pmid = {39596223}, issn = {1422-0067}, support = {HEAF67300087//Thailand Science research and Innovation Fund Chulalongkorn University/ ; }, mesh = {Animals ; *Biofilms/growth &amp; development ; *Klebsiella pneumoniae/physiology ; *Candida albicans/physiology ; *Neutrophils/immunology/metabolism ; Mice ; *Klebsiella Infections/microbiology/immunology ; Mice, Inbred C57BL ; Cytokines/metabolism ; Inflammation/pathology ; Extracellular Traps/metabolism ; Pneumonia/microbiology/immunology ; Humans ; }, abstract = {Due to the possible coexistence of Klebsiella pneumoniae (KP) and Candida albicans (CA), strains of KP and CA with biofilm production properties clinically isolated from patients were tested. The production of biofilms from the combined organisms (KP+CA) was higher than the biofilms from each organism alone, as indicated by crystal violet and z-stack immunofluorescence. In parallel, the bacterial abundance in KP + CA was similar to KP, but the fungal abundance was higher than CA (culture method), implying that CA grows better in the presence of KP. Proteomic analysis was performed to compare KP + CA biofilm to KP biofilm alone. With isolated mouse neutrophils (thioglycolate induction), KP + CA biofilms induced less prominent responses than KP biofilms, as determined by (i) neutrophilic supernatant cytokines (ELISA) and (ii) neutrophil extracellular traps (NETs), using immunofluorescent images (neutrophil elastase, myeloperoxidase, and citrullinated histone 3), peptidyl arginine deiminase 4 (PAD4) expression, and cell-free DNA. Likewise, intratracheal KP + CA in C57BL/6 mice induces less severe pneumonia than KP alone, as indicated by organ injury (serum creatinine and alanine transaminase) (colorimetric assays), cytokines (ELISA), bronchoalveolar lavage fluid parameters (bacterial culture and neutrophil abundances using a hemocytometer), histology score (H&amp;E stains), and NETs (immunofluorescence on the lung tissue). In conclusion, the biofilm biomass of KP + CA was mostly produced from CA with less potent neutrophil activation and less severe pneumonia than KP alone. Hence, fungi in the respiratory tract might benefit the host in some situations, despite the well-known adverse effects of fungi.}, }
@article {pmid39596184, year = {2024}, author = {Wang, Z and Wu, Y and Liu, M and Chen, L and Xiao, K and Huang, Z and Zhao, Y and Wang, H and Ding, Y and Lin, X and Zeng, J and Peng, F and Zhang, J and Wang, J and Wu, Q}, title = {The Gene Cluster Cj0423-Cj0425 Negatively Regulates Biofilm Formation in Campylobacter jejuni.}, journal = {International journal of molecular sciences}, volume = {25}, number = {22}, pages = {}, pmid = {39596184}, issn = {1422-0067}, support = {2023YFD1801000//National Key Research and Development Program of China/ ; 2020B0301030005//Guangdong Major Project of Basic and Applied Basic Research/ ; 2021TQ06N119//Talent Support Project of Guangdong/ ; 2022GDASZH-2022020402-1//Guangdong Academy of Sciences Project/ ; }, mesh = {*Biofilms/growth &amp; development ; *Campylobacter jejuni/genetics/physiology/growth &amp; development/metabolism ; *Multigene Family ; *Bacterial Proteins/genetics/metabolism ; *Gene Expression Regulation, Bacterial ; Quorum Sensing/genetics ; Flagella/genetics/metabolism ; Fatty Acids/metabolism ; }, abstract = {Campylobacter jejuni (C. jejuni) is a zoonotic foodborne pathogen that is widely distributed worldwide. Its optimal growth environment is microaerophilic conditions (5% O2, 10% CO2), but it can spread widely in the atmospheric environment. Biofilms are thought to play an important role in this process. However, there are currently relatively few research works on the regulatory mechanisms of C. jejuni biofilm formation. In this study, a pan-genome analysis, combined with the analysis of biofilm phenotypic information, revealed that the gene cluster Cj0423-Cj0425 is associated with the negative regulation of biofilm formation in C. jejuni. Through gene knockout experiments, it was observed that the Cj0423-Cj0425 mutant strain significantly increased biofilm formation and enhanced flagella formation. Furthermore, pull-down assay revealed that Cj0424 interacts with 93 proteins involved in pathways such as fatty acid synthesis and amino acid metabolism, and it also contains the quorum sensing-related gene luxS. This suggests that Cj0423-Cj0425 affects fatty acid synthesis and amino acid metabolism, influencing quorum sensing and strain motility, ultimately inhibiting biofilm formation.}, }
@article {pmid39595342, year = {2024}, author = {Huang, Y and Chen, P and Cao, H and Zhou, Z and Xu, T}, title = {Characterization of Pseudomonas aeruginosa Isolated from Bovine Mastitis in Northern Jiangsu Province and Correlation to Drug Resistance and Biofilm Formability.}, journal = {Animals : an open access journal from MDPI}, volume = {14}, number = {22}, pages = {}, pmid = {39595342}, issn = {2076-2615}, support = {32102731//National Natural Science Foundation of China/ ; 2023M732994//China Postdoctoral Science Foundation/ ; IJRLD-KF202214//The Open Project Program of International Joint Research Laboratory in Universities of Jiangsu Province of China for Domestic Animal Germplasm Resources and Genetic Improvement/ ; }, abstract = {This study aimed to provide experimental support for the prevention and treatment of Pseudomonas aeruginosa infections and to elucidate the epidemiological distribution of resistance and virulence genes of Pseudomonas aeruginosa from mastitis in dairy cows in the northern part of Jiangsu Province and their relationship with the biofilm-forming ability of the strains. Mastitis presents a significant challenge within dairy farming, adversely impacting the health of dairy cows and precipitating substantial economic losses in milk production. In this study, Pseudomonas aeruginosa (PA) was isolated and identified from mastitis milk samples in Jiangsu Province, China. In order to characterize the isolates, multilocus sequence typing (MLST), drug resistance phenotypes, virulence genes, and biofilm formations were detected. The isolation and identification of pathogenic bacteria from 168 clinical mastitis milk samples using 16S rRNA and PCR revealed 63 strains of Pseudomonas aeruginosa, which were determined to be highly homologous according to phylogenetic tree analysis. In addition, the MLST indicated five major ST types, namely ST277, ST450, ST571, ST641, and ST463. The susceptibility to 10 antimicrobials was determined, and it was found that 63 strains of Pseudomonas aeruginosa did not have a strong resistance to the antimicrobials in general. However, there were differences in the phenotypes' resistance to antimicrobials among the different ST types. It was also found that the more resistant the strains were to antimicrobials, the lower the carriage of virulence genes detected. The biofilm content was measured using the semi-quantitative crystal violet method. It was found that there were a few strains with medium or strong biofilm-forming abilities. However, the number of virulence genes carried by the 63 strains of Pseudomonas aeruginosa was inversely proportional to the biofilm-forming ability. It was also found that there were significantly more Pseudomonas aeruginosa in the biofilm state than in the planktonic state and that strains with strong biofilm-forming abilities were more resistant to antimicrobials.}, }
@article {pmid39594124, year = {2024}, author = {Hu, M and Zhou, Z and Liu, C and Zhan, Z and Cui, Y and He, S and Shi, X}, title = {Roles of Response Regulators in the Two-Component System in the Formation of Stress Tolerance, Motility and Biofilm in Salmonella Enteritidis.}, journal = {Foods (Basel, Switzerland)}, volume = {13}, number = {22}, pages = {}, pmid = {39594124}, issn = {2304-8158}, support = {32172316//National Natural Science Foundation of China/ ; 2023M742281//China Postdoctoral Science Foundation/ ; }, abstract = {Two-component systems (TCS) of Salmonella enterica serovar Enteritidis are composed of a histidine kinase and a response regulator (RR) and represent a critical mechanism by which bacteria develop resistance to environmental stress. Here, we characterized the functions of RRs in TCS in the formation of stress tolerance, motility and biofilm using twenty-six S. Enteritidis RR-encoding gene deletion mutants. The viability results unraveled their essential roles in resistance to elevated temperature (GlrR), pH alterations (GlrR, TctD, YedW, ArcA and YehT), high salt (PhoB, BaeR, CpxR, PhoP, UvrY and TctD), oxidative stress (PhoB, YedW, BaeR, ArcA, PhoP, UvrY, PgtA and QseB) and motility (ArcA, GlnG, PgtA, PhoB, UhpA, OmpR, UvrY and QseB) of S. Enteritidis. The results of the crystal violet staining, microscopy observation and Congo red binding assays demonstrated that the absence of ArcA, GlnG, PhoP, OmpR, ZraR or SsrB in S. Enteritidis led to a reduction in biofilms and an impairment in red/dry/rough macrocolony formation, whereas the absence of UvrY exhibited an increase in biofilms and formed a brown/smooth/sticky macrocolony. The results indicated the regulatory effects of these RRs on the production of biofilm matrix, curli fimbriae and cellulose. Our findings yielded insights into the role of TCSs, making them a promising target for combating S. Enteritidis.}, }
@article {pmid39593330, year = {2024}, author = {Rodrigues Carneiro, C and Nogueira Leite, N and de Abreu Oliveira, AV and Dos Santos Oliveira, M and Wischral, D and Renon Eller, M and Gonçalves Machado, S and de Oliveira, EB and Edgard Luera Pena, W}, title = {Mathematical modeling for the prediction of biofilm formation and removal in the food industry as strategy to control microbiological resistance.}, journal = {Food research international (Ottawa, Ont.)}, volume = {197}, number = {Pt 1}, pages = {115248}, doi = {10.1016/j.foodres.2024.115248}, pmid = {39593330}, issn = {1873-7145}, mesh = {*Biofilms/growth &amp; development ; *Food Microbiology ; *Models, Theoretical ; Food Industry ; Food Handling/methods ; Food Contamination/prevention &amp; control ; Food Safety ; Bacterial Adhesion ; }, abstract = {The formation of biofilms in the food industry poses significant economic, social, and public health challenges. Concurrently, mathematical models have emerged as promising tools for investigating microbial contamination and biofilm dynamics. This study evaluates the application of these models, highlighting their ability to identify critical parameters influencing microbial adhesion and to develop strategies for disrupting biofilm formation. Furthermore, it explores how mathematical modeling can address current limitations in food safety, discussing practical challenges such as the complexity of biological systems and the necessity for experimental validation of proposed models. In this context, the review assesses both the potential and the challenges associated with employing mathematical models for microbial control in food processing, examining the specifics of existing models. Additionally, it underscores the need for a comprehensive understanding of biofilm formation mechanisms and control techniques to fully leverage the benefits of these models. The findings demonstrate that mathematical modeling is a viable, innovative, and promising approach for optimizing biofilm prevention and control strategies in the food industry. To achieve more effective biofilm management and ensure consumer food safety, future research should focus on applying these models to various real-world scenarios.}, }
@article {pmid39593289, year = {2024}, author = {Anamul Hasan Chowdhury, M and Ashrafudoulla, M and Isaïe Ulrich Mevo, S and Mahamud, AGMSU and Sanat Anjum Reem, C and Jie-Won Ha, A and Ha, SD}, title = {Efficacy of orange terpene against Escherichia coli biofilm on beef and food contact surfaces.}, journal = {Food research international (Ottawa, Ont.)}, volume = {197}, number = {Pt 1}, pages = {115204}, doi = {10.1016/j.foodres.2024.115204}, pmid = {39593289}, issn = {1873-7145}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Escherichia coli/drug effects ; *Stainless Steel ; *Food Microbiology ; *Red Meat/microbiology ; *Terpenes/pharmacology ; Animals ; *Microbial Sensitivity Tests ; Cattle ; Anti-Bacterial Agents/pharmacology ; Citrus sinensis/chemistry ; Polyethylene Terephthalates/chemistry ; Rubber ; Polyethylene/chemistry ; Humans ; Food Contamination/prevention &amp; control ; }, abstract = {Foodborne pathogen Escherichia coli frequently causes foodborne infections. In our study, we investigated the antibiofilm activity of orange terpene (OT) against E. coli biofilms on a food surface (beef) and different surfaces that come into touch with food, including stainless steel (SS), polyethylene terephthalate (PET), low-density polyethylene (LDPE), and rubber (SR). The study findings revealed that OT significantly (P < 0.05) eliminated 48-h-old biofilms from all food contact surfaces (SS: 2.09 log CFU/cm[2], PET: 1.95 log CFU/cm[2], LDPE: 1.94 log CFU/cm[2], and SR: 1.4 log CFU/cm[2]). Additionally, on beef surfaces, OT at a minimum inhibitory concentration (MIC) of 0.13 % demonstrated the ability to inhibit biofilm development by approximately 1.5 log CFU/cm[2] and reduced pre-formed biofilms by 2.02 log CFU/cm[2]. Our sensory evaluations showed that it had no adverse impacts on beef color and texture, although it slightly altered the natural odor of beef. Quantitative and qualitative assessments showed that OT has strong bactericidal actions on biofilm populations. It significantly altered cell surface hydrophobicity, reduced cellular ATP levels, and inhibited cell auto-aggregation in planktonic cells (P < 0.05). As a result, our findings emphasize the antibacterial potentiality of OT in reducing the biofilm of E. coli in the food sector.}, }
@article {pmid39592778, year = {2024}, author = {Sur, S and Sathiavelu, M}, title = {Functional profiling of the rhizospheric Exiguobacterium sp. for dimethoate degradation, PGPR activity, biofilm development, and ecotoxicological risk.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {29361}, pmid = {39592778}, issn = {2045-2322}, mesh = {*Dimethoate/toxicity/metabolism ; *Biofilms/drug effects/growth &amp; development ; *Biodegradation, Environmental ; *Rhizosphere ; Soil Microbiology ; Gas Chromatography-Mass Spectrometry ; Indoleacetic Acids/metabolism ; Soil Pollutants/toxicity/metabolism ; Hydrogen Cyanide/metabolism ; Ammonia/metabolism ; Ecotoxicology ; Hexachlorocyclohexane/metabolism ; }, abstract = {This study introduces an indigenous bacterial strain, Exiguobacterium sp. (L.O), isolated from sugarcane fields in Sevur, Tamil Nadu, which has adapted to prolonged exposure to dimethoate. The strain demonstrated the capability to utilize 150 ppm of dimethoate as its sole carbon source, achieving a remarkable degradation rate of 95.87% within 5 days in mineral salt media. Gas chromatography-mass spectrometry (GC-MS) analyses identified the presence of intermediate by-products formed during degradation, like methyl diethanol amine and aspartyl glycine ethyl ester. Notably, phosphorothioic O, O, S-acid, an expected end product in the degradation of dimethoate, was also identified, further confirming the strain's effective metabolic breakdown of the pesticide. Further degradation study and analysis of changes in functional group was performed by FTIR, and a hypothetical degradation pathway was elucidated showing the course of dimethoate metabolism by the strain. Exiguobacterium sp. (L.O) also displayed significant plant growth-promoting traits, including the production of HCN, IAA, and ammonia and the formation of biofilms, which enhance its utility in agricultural applications. The ecotoxicity study revealed the degradation by-products exhibited reduced toxicity compared to the parent compound dimethoate, highlighting the strain's potential not only for bioremediation but also for supporting sustainable agricultural practices. This research presents a novel application of Exiguobacterium sp. (L.O), integrating the bioremediation of the organophosphate pesticide dimethoate with agricultural enhancement. This approach is critical for addressing the challenges associated with pesticide pollution in agricultural practices. This study is likely the first to demonstrate the application of this strain in the degradation of dimethoate, as suggested by an extensive review of the literature.}, }
@article {pmid39590782, year = {2024}, author = {Domingos, LTS and de Moraes, DC and Santos, MFC and Curvelo, JAR and Bayona-Pacheco, B and Marquez, EA and Martinez, AWB and Berlinck, RGS and Ferreira-Pereira, A}, title = {Batzelladine D, a Marine Natural Product, Reverses the Fluconazole Resistance Phenotype Mediated by Transmembrane Transporters in Candida albicans and Interferes with Its Biofilm: An In Vitro and In Silico Study.}, journal = {Marine drugs}, volume = {22}, number = {11}, pages = {}, pmid = {39590782}, issn = {1660-3397}, mesh = {*Biofilms/drug effects ; *Fluconazole/pharmacology ; *Candida albicans/drug effects ; *Drug Resistance, Fungal/drug effects ; *Antifungal Agents/pharmacology ; Animals ; *Caenorhabditis elegans/drug effects/microbiology ; *Saccharomyces cerevisiae/drug effects ; Membrane Transport Proteins/metabolism/genetics/drug effects ; Biological Products/pharmacology ; Microbial Sensitivity Tests ; Phenotype ; Computer Simulation ; Fungal Proteins/metabolism/genetics ; }, abstract = {Numerous Candida species are responsible for fungal infections; however, Candida albicans stands out among the others. Treatment with fluconazole is often ineffective due to the resistance phenotype mediated by transmembrane transporters and/or biofilm formation, mechanisms of resistance commonly found in C. albicans strains. A previous study by our group demonstrated that batzelladine D can inhibit the Pdr5p transporter in Saccharomyces cerevisiae. In the present study, our aim was to investigate the efficacy of batzelladine D in inhibiting the main efflux pumps of Candida albicans, CaCdr1p and CaCdr2p, as well as to evaluate the effect of the compound on C. albicans biofilm. Assays were conducted using a clinical isolate of Candida albicans expressing both transporters. Additionally, to allow the study of each transporter, S. cerevisiae mutant strains overexpressing CaCdr1p or CaCdr2p were used. Batzelladine D was able to reverse the fluconazole resistance phenotype by acting on both transporters. The compound synergistically improved the effect of fluconazole against the clinical isolate when tested in the Caenorhabditis elegans animal model. Moreover, the compound disrupted the preformed biofilm. Based on the obtained data, the continuation of batzelladine D studies as a potential new antifungal agent and/or chemosensitizer in Candida albicans infections can be suggested.}, }
@article {pmid39590685, year = {2024}, author = {Zhang, R and Wiederhold, N and Calderone, R and Li, D}, title = {Biofilm Formation in Clinical Isolates of Fusarium.}, journal = {Journal of fungi (Basel, Switzerland)}, volume = {10}, number = {11}, pages = {}, pmid = {39590685}, issn = {2309-608X}, abstract = {Many microbial pathogens form biofilms, assemblages of polymeric compounds that play a crucial role in establishing infections. The biofilms of Fusarium species also contribute to high antifungal resistance. Using our collection of 29 clinical Fusarium isolates, we focused on characterizing differences in thermotolerance, anaerobic growth, and biofilm formation across four Fusarium species complexes commonly found in clinical settings. We investigated the role of carbon sources, temperature, and fungal morphology on biofilm development. Using fluorescence microscopy, we followed the stages of biofilm formation. Biofilms were screened for sensitivity/resistance to the antifungals voriconazole (VOR), amphotericin B (AmB), and 5-fluorocytosine (5-FC). Our findings revealed generally poor thermotolerance and growth under anaerobic conditions across all Fusarium species. VOR was more effective than AmB in controlling biofilm formation, but the combination of VOR, AmB, and 5-FC significantly reduced biofilm formation across all species. Additionally, Fusarium biofilm formation varied under non-glucose carbon sources, highlighting the species' adaptability to different nutrient environments. Notably, early stage biofilms were primarily composed of lipids, while polysaccharides became dominant in late-stage biofilms, suggesting a dynamic shift in biofilm composition over time.}, }
@article {pmid39590365, year = {2024}, author = {Khan, MA and Azam, M and Younus, H}, title = {In Silico and In Vitro Studies to Explore the Effect of Thymoquinone on Isocitrate Lyase, Biofilm Formation, and the Expression of Some Virulence Genes in Candida albicans.}, journal = {Current issues in molecular biology}, volume = {46}, number = {11}, pages = {12951-12967}, pmid = {39590365}, issn = {1467-3045}, support = {2023-SDG-I-HMSRC-36570//Qassim University, represented by the Deanship of Scientific Research/ ; }, abstract = {Thymoquinone (TQ), a bioactive compound from black cumin (Nigella sativa), has demonstrated a broad range of therapeutic effects. The aim of this study is to evaluate the antifungal efficacy of TQ by targeting key virulence factors in Candida albicans, specifically focusing on isocitrate lyase (ICL) activity, biofilm formation, and gene expression. This study explored TQ's impact on ICL, a decisive enzyme in the glyoxylate cycle, along with its effect on hyphal formation, biofilm development, and the virulent gene expression of C. albicans through in silico and in vitro studies. Molecular docking revealed a binding energy of -6.4 kcal/mol between TQ and ICL, indicating moderate affinity. The stability of the ICL-TQ complex was validated through 50 ns molecular dynamics simulations, showing the root mean square deviation (RMSD) values of 0.35 nm for ICL and 0.38 nm for the complex. In vitro studies further validated these findings, showing a dose-dependent inhibition of ICL activity. TQ at 2 µg/mL reduced enzyme activity by 57%, and at 4 µg/mL, by 91.4%. Additionally, TQ disrupted the yeast-to-hyphae switch, a key virulence factor, with 1 and 2 µg/mL doses significantly inhibiting hyphal formation. The biofilm formation was similarly affected, with a 58% reduction at 2 µg/mL and an 83% reduction at 4 µg/mL. TQ also downregulated the ALS1 and HWP1 genes that are associated with adhesion and biofilm development, demonstrating its broad-spectrum antifungal activity. These findings suggest that TQ is a promising candidate for antifungal therapies, targeting multiple virulence factors in C. albicans and potentially overcoming biofilm-associated drug resistance. Future research should focus on in vivo validation, optimization for clinical applications, and expanding its spectrum against other drug-resistant fungal species.}, }
@article {pmid39590364, year = {2024}, author = {Emeka, PM and Badger-Emeka, LI and Thirugnanasambantham, K}, title = {Virtual Screening and Meta-Analysis Approach Identifies Factors for Inversion Stimulation (Fis) and Other Genes Responsible for Biofilm Production in Pseudomonas aeruginosa: A Corneal Pathogen.}, journal = {Current issues in molecular biology}, volume = {46}, number = {11}, pages = {12931-12950}, pmid = {39590364}, issn = {1467-3045}, support = {KSRG-2023-107//King Salman center For Disability Research/ ; }, abstract = {Bacterial keratitis caused by Pseudomonas aeruginosa is indeed a serious concern due to its potential to cause blindness and its resistance to antibiotics, partly attributed to biofilm formation and cytotoxicity to the cornea. The present study uses a meta-analysis of a transcriptomics dataset to identify important genes and pathways in biofilm formation of P. aeruginosa induced keratitis. By combining data from several studies, meta-analysis can enhance statistical power and robustness, enabling the identification of 83 differentially expressed candidate genes, including fis that could serve as therapeutic targets. The approach of combining meta-analysis with virtual screening and in vitro methods provides a comprehensive strategy for identifying potential target genes and pathways crucial for bacterial biofilm formation and development anti-biofilm medications against P. aeruginosa infections. The study identified 83 candidate genes that exhibited differential expression in the biofilm state, with fis proposed as an ideal target for therapy for P. aeruginosa biofilm formation. These techniques, meta-analysis, virtual screening, and invitro methods were used in combination to diagnostically identify these genes, which play a significant role in biofilms. This finding has highlighted a hallmark target list for P. aeruginosa anti-biofilm potential treatments.}, }
@article {pmid39589820, year = {2024}, author = {Babeer, A and Liu, Y and Ren, Z and Xiang, Z and Oh, MJ and Pandey, NK and Simon-Soro, A and Huang, R and Karabucak, B and Cormode, DP and Chen, C and Koo, H}, title = {Ferumoxytol nanozymes effectively target chronic biofilm infections in apical periodontitis.}, journal = {The Journal of clinical investigation}, volume = {135}, number = {3}, pages = {}, pmid = {39589820}, issn = {1558-8238}, support = {R01 DE025848/DE/NIDCR NIH HHS/United States ; R21 DE033128/DE/NIDCR NIH HHS/United States ; R90 DE031532/DE/NIDCR NIH HHS/United States ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; Humans ; *Periapical Periodontitis/drug therapy/microbiology ; *Ferrosoferric Oxide/pharmacology ; Fusobacterium nucleatum/drug effects ; Male ; Female ; Enterococcus faecalis/drug effects/genetics ; Adult ; Hydrogen Peroxide/metabolism ; }, abstract = {Bacterial biofilms are pervasive and recalcitrant to current antimicrobials, causing numerous infections. Iron oxide nanozymes, including an FDA-approved formulation, ferumoxytol (FMX), show potential against biofilm infections via catalytic activation of hydrogen peroxide (H2O2). However, clinical evidence regarding the efficacy and therapeutic mechanisms of FMX is lacking. Here, we investigate whether FMX nanozymes can treat chronic biofilm infections and compare their bioactivity to that of the gold standard sodium hypochlorite (NaOCl), a potent but caustic disinfectant. Clinical performance was assessed in patients with apical periodontitis, an intractable endodontic infection affecting half of the global adult population. Data show robust antibiofilm activity by a single application of FMX with H2O2 achieving results comparable to those seen with NaOCl without adverse effects. FMX binds efficiently to the bacterial pathogens Enterococcus faecalis and Fusobacterium nucleatum and remains catalytically active without being affected by dental tissues. This allows for effective eradication of endodontic biofilms via on-site free radical generation without inducing cytotoxicity. Unexpectedly, FMX promotes growth of stem cells of the apical papilla (SCAPs), with transcriptomic analyses revealing upregulation of proliferation-associated pathways and downregulation of cell cycle suppressor genes. Notably, FMX activates SCAP pluripotency and WNT/NOTCH signaling that induces its osteogenic capacity. Together, these results show that FMX nanozymes are clinically effective against severe chronic biofilm infection with pathogen targeting and unique stem cell-stimulatory properties, offering a regenerative approach to antimicrobial therapy.}, }
@article {pmid39589773, year = {2024}, author = {Titouche, Y and Akkou, M and Djaoui, Y and Chergui, A and Mechoub, D and Bentayeb, L and Fatihi, A and Nia, Y and Hennekinne, JA}, title = {Investigation of Biofilm Formation Ability and Antibiotic Resistance of Staphylococcus aureus Isolates from Food Products.}, journal = {Foodborne pathogens and disease}, volume = {}, number = {}, pages = {}, doi = {10.1089/fpd.2024.0121}, pmid = {39589773}, issn = {1556-7125}, abstract = {Staphylococcus aureus is one of the major causes of foodborne diseases and its presence in food products may poses a public health challenge. The aims of this study were to assess in vitro the capacity of S. aureus isolates from foods to form biofilm and to determine their antibiotic susceptibility. A total of 80 S. aureus isolates were characterized. The slime production ability was evaluated by congo-red agar (CRA) and the biofilm formation was carried out by microtiter-plate method (MPM). Resistance of isolates to eight antibiotics was determined using disc diffusion method. Sixty-four (80%) of the isolates were slime producers on congo-red agar. However, all isolates were biofilm producers on microtiter-plate method. The highest resistance profiles were ascribed to penicillin G (91.25%) and tetracycline (41.25%). Twelve isolates were methicillin-resistant (MRSA) harboring the mecA gene. All of these MRSA isolates were negative for the genes of the Panton Valentine leukocidine (lukF/S-PV). Typing of the MRSA isolates indicated that they belonged to three spa-types including t024, t450 and t688. The presence of biofilm producers and multidrug resistant isolates (MRSA) in food samples can represent a risk for public health. Therefore, an efficient control and effective measures were needed along the production chain to ensure the food safety.}, }
@article {pmid39589428, year = {2024}, author = {Liu, Y and Fang, B and Wuri, G and Lan, H and Wang, R and Sun, Y and Zhao, W and Hung, WL and Zhang, M}, title = {From Biofilm to Breath: The Role of Lacticaseibacillus paracasei ET-22 Postbiotics in Combating Oral Malodor.}, journal = {Journal of agricultural and food chemistry}, volume = {72}, number = {49}, pages = {27203-27214}, doi = {10.1021/acs.jafc.4c07381}, pmid = {39589428}, issn = {1520-5118}, mesh = {*Biofilms/drug effects ; *Halitosis/microbiology/metabolism/drug therapy/therapy ; Humans ; *Lacticaseibacillus paracasei/metabolism/physiology ; Probiotics ; Volatile Organic Compounds/chemistry/metabolism ; Streptococcus mutans/drug effects/physiology ; Fusobacterium nucleatum/physiology/drug effects/metabolism ; Sulfur Compounds/metabolism ; }, abstract = {Previous studies demonstrated that sufferers with halitosis can be significantly improved with Lacticaseibacillus paracasei ET-22 (ET-22) postbiotics intervention. The objectives of this investigation were to identify the primary components responsible for inhibiting oral malodor. This study demonstrated that cell-free supernatants (CFSs) were more effective in inhibiting production of volatile sulfur compounds (VSCs). Untargeted metabolomics identified CFSs as primarily consisting of organic acids, lipids, peptides, and nucleotides. Among the potential active components, phenyllactic acid (PLA) and peptide GP(Hyp)GAG significantly inhibited microbial-induced VSCs production, with VSC concentrations reduced by 42.7% and 44.6%, respectively. Given the correlation between biofilms and halitosis, microstructural changes in biofilms were examined. PLA suppressed the biomass of the biofilm by 41.7%, while the biofilm thickness was reduced from 202.3 to 70.0 μm. GP(Hyp)GAG intervention reduced the abundance of Fusobacterium nucleatum and Streptococcus mutans within the biofilm, and the expression of biofilm-forming genes FadA and Gtfb were also suppressed by 41.8% and 59.4%. Additionally, the VSC production capacities were reduced due to the decrease in VSC producing bacteria (F. nucleatum, Prevotella intermedia, and Solobacterium moorei) and down-regulation of Cdl and Mgl genes. Collectively, the current study proved that PLA and GP(Hyp)GAG may be the main contributors to halitosis inhibition by ET-22 postbiotics.}, }
@article {pmid39589111, year = {2025}, author = {Mu, K and He, M and Chen, H and Liu, T and Fan, Y and Tao, Y and Feng, H and Huang, Q and Xiao, Y and Chen, W}, title = {Tetracycline induces wsp operon expression to promote biofilm formation in Pseudomonas putida.}, journal = {Applied and environmental microbiology}, volume = {91}, number = {1}, pages = {e0107124}, pmid = {39589111}, issn = {1098-5336}, support = {31900054//MOST | National Natural Science Foundation of China (NSFC)/ ; 42020104003//MOST | National Natural Science Foundation of China (NSFC)/ ; 2662022SKQD002//Fundamental research funds of the central university/ ; }, mesh = {*Pseudomonas putida/genetics/drug effects/physiology ; *Biofilms/drug effects/growth &amp; development ; *Operon ; *Tetracycline/pharmacology ; *Gene Expression Regulation, Bacterial/drug effects ; *Anti-Bacterial Agents/pharmacology ; *Bacterial Proteins/genetics/metabolism ; Promoter Regions, Genetic ; Cyclic GMP/metabolism/analogs &amp; derivatives ; }, abstract = {The overuse and wanton discharge of antibiotics produces a threat to bacteria in the environment, which, in turn, stimulates the more rapid emergence of antibiotic-resistant bacteria. Pseudomonas putida actively forms biofilms to protect the population under tetracycline stress, but the molecular mechanism remains unclear. This study found that tetracycline at sub-minimal inhibitory concentrations increased cyclic diguanylate (c-di-GMP), a second messenger that positively regulates biofilm formation. Four c-di-GMP-metabolizing proteins were found to be involved in the tetracycline-mediated biofilm promotion, including DibA, WspR, PP_3242, and PP_3319. Among them, the diguanylate cyclase WspR displayed the most significant effect on c-di-GMP level and biofilm formation. WspR belongs to the wsp operon comprising seven genes (wspA-wspF and wspR). The wsp operon contained six promoters, including one major start promoter (PwspA) and five internal promoters (PwspB, PwspC, PwspD, PwspF, and PwspR), and tetracycline promoted the activity of PwspA. The stress-response sigma factor RpoS directly bound to PwspA and positively regulated its activity under tetracycline stress. Moreover, RpoS was required for tetracycline to induce PwspA activity and promote biofilm formation. Our results enrich the transcriptional regulation of the wsp operon and reveal the mechanism by which tetracycline promotes biofilm formation in P. putida.IMPORTANCEThe overuse and wanton discharge of antibiotics produces a threat to bacteria in the environment, which, in turn, stimulates the more rapid emergence of antibiotic-resistant bacteria. The Pseudomonas putida actively forms biofilm against antibiotic threats, but the mechanism remains unclear. Here, our results showed that tetracycline treatment at sub-minimal inhibitory concentrations could induce the expression of the Wsp system via the sigma factor RpoS in P. putida, resulting in elevated c-di-GMP levels, which leads to increased biofilm formation. The wsp operon contains one major promoter and five internal promoters, and RpoS directly binds to the major promoter to promote its activity.}, }
@article {pmid39589067, year = {2024}, author = {Popczyk, P and Ghinet, A and Bortolus, C and Kamus, L and Lensink, MF and de Ruyck, J and Sendid, B and Dubar, F}, title = {Antifungal and anti-biofilm effects of hydrazone derivatives on Candida spp.}, journal = {Journal of enzyme inhibition and medicinal chemistry}, volume = {39}, number = {1}, pages = {2429109}, pmid = {39589067}, issn = {1475-6374}, mesh = {*Biofilms/drug effects ; *Antifungal Agents/pharmacology/chemistry/chemical synthesis ; *Hydrazones/pharmacology/chemistry/chemical synthesis ; *Candida/drug effects ; *Microbial Sensitivity Tests ; Structure-Activity Relationship ; *Dose-Response Relationship, Drug ; Molecular Structure ; Animals ; Humans ; }, abstract = {Worldwide, invasive candidiasis are a burden for the health system due to difficulties to manage patients, to the increasing of the resistance of the current therapeutics and the emergence of naturally resistant species of Candida. In this context, the development of innovative antifungal drugs is urgently needed. During invasive candidiasis, yeast is submitted to many stresses (oxidative, thermic, osmotic) in the human host. In order to resist in this context, yeast develops different strategy, especially the biosynthesis of trehalose. Starting from the 3D structural data of TPS2, an enzyme implicated in trehalose biosynthesis, we identified hydrazone as an interesting scaffold to design new antifungal drugs. Interestingly, our hydrazone derivatives which demonstrate antifungal and anti-biofilm effects on Candida spp., are non-toxic in in vitro and in vivo models (Galleria mellonella).}, }
@article {pmid39588812, year = {2024}, author = {Frison, SS and Borges, EL and Guedes, ACM and Honorato-Sampaio, K}, title = {Biofilm and Its Characteristics in Venous Ulcers.}, journal = {Journal of wound, ostomy, and continence nursing : official publication of The Wound, Ostomy and Continence Nurses Society}, volume = {51}, number = {6}, pages = {445-453}, pmid = {39588812}, issn = {1528-3976}, mesh = {Humans ; *Biofilms ; *Varicose Ulcer/microbiology/physiopathology ; Male ; Female ; Aged ; Middle Aged ; Brazil ; Wound Healing/physiology ; Aged, 80 and over ; Pseudomonas aeruginosa/pathogenicity ; Adult ; }, abstract = {PURPOSE: The aim of the study was to analyze the characteristics of the biofilm of venous ulcers in terms of location and formation and to relate the presence of the biofilm to ulcer characteristics including duration, injured area, and necrotic tissue.<br><br>DESIGN: Descriptive clinical study.<br><br>MATERIALS AND METHODS: We obtained 2 biopsy fragments (tissue samples) from 44 patients with venous ulcers treated at a public outpatient clinic in a university hospital in Belo Horizonte, Brazil. Ulcers were photographed and classified according to the duration. In addition, the wound size and proportion of wound surface covered by necrotic tissue were measured. One fragment from each ulcer underwent microbiological analysis, while the other was analyzed using transmission electron microscopy. Data analysis was limited to fragments from patients with bacteria in the microbiological analysis.<br><br>RESULTS: Data analysis is based on samples obtained from 21 ulcers in 21 patients who had bacteria in their ulcer based on microbiologic analysis of a tissue sample. Most ulcers were open for 2 to 10&#xa0;years, 57% (n&#xa0;=&#xa0;12) were 16 cm2 or smaller, and the proportion of the wound bed covered by necrotic tissue coverage varied widely. Of the 21/44 patients (48%) with bacteria in their ulcers, only 3 patients had bacterial biofilm present in the transmission electron microscopy, corresponding to 7% of the 44 patients. Pseudomonas aeruginosa was the most frequent bacterium, identified in 10 fragments. The biofilm was not present on the surface but in a layer slightly below it. The detection of biofilms was not directly related to the duration of the ulcer. It was not possible to establish a correlation between the size of the lesion and the presence of these microorganisms due to the small sample size.<br><br>CONCLUSIONS: Our findings indicate that detecting biofilm in venous ulcers is challenging, as it does not uniformly occur throughout the wound bed, can occur at different depths, and is often not present on the wound surface. There is a need to develop studies that can contribute to the detection of biofilm in clinical practice.}, }
@article {pmid39588362, year = {2024}, author = {Debener, N and Heine, N and Legutko, B and Denkena, B and Prasanthan, V and Frings, K and Torres-Mapa, ML and Heisterkamp, A and Stiesch, M and Doll-Nikutta, K and Bahnemann, J}, title = {Optically accessible, 3D-printed flow chamber with integrated sensors for the monitoring of oral multispecies biofilm growth in vitro.}, journal = {Frontiers in bioengineering and biotechnology}, volume = {12}, number = {}, pages = {1483200}, pmid = {39588362}, issn = {2296-4185}, abstract = {The formation of pathogenic multispecies biofilms in the human oral cavity can lead to implant-associated infections, which may ultimately result in implant failure. These infections are neither easily detected nor readily treated. Due to high complexity of oral biofilms, detailed mechanisms of the bacterial dysbiotic shift are not yet even fully understood. In order to study oral biofilms in more detail and develop prevention strategies to fight implant-associated infections, in vitro biofilm models are sorely needed. In this study, we adapted an in vitro biofilm flow chamber model to include miniaturized transparent 3D-printed flow chambers with integrated optical pH sensors - thereby enabling the microscopic evaluation of biofilm growth as well as the monitoring of acidification in close proximity. Two different 3D printing materials were initially characterized with respect to their biocompatibility and surface topography. The functionality of the optically accessible miniaturized flow chambers was then tested using five-species biofilms (featuring the species Streptococcus oralis, Veillonella dispar, Actinomyces naeslundii, Fusobacterium nucleatum, and Porphyromonas gingivalis) and compared to biofilm growth on titanium specimens in the established flow chamber model. As confirmed by live/dead staining and fluorescence in situ hybridization via confocal laser scanning microscopy, the flow chamber setup proved to be suitable for growing reproducible oral biofilms under flow conditions while continuously monitoring biofilm pH. Therefore, the system is suitable for future research use with respect to biofilm dysbiosis and also has great potential for further parallelization and adaptation to achieve higher throughput as well as include additional optical sensors or sample materials.}, }
@article {pmid39587976, year = {2025}, author = {Yan, N and Zhou, H and Jin, P and Li, T and Liu, Q and Ning, H and Ma, Z and Feng, L and Jin, T and Deng, Y and Wu, Z}, title = {A Multifunctional Cobalt-Containing Implant for Treating Biofilm Infections and Promoting Osteointegration in Infected Bone Defects Through Macrophage-Mediated Immunomodulation.}, journal = {Advanced science (Weinheim, Baden-Wurttemberg, Germany)}, volume = {12}, number = {3}, pages = {e2409200}, pmid = {39587976}, issn = {2198-3844}, support = {JL06120001H//Joint Laboratory of Plasma Application Technology Funding/ ; R2023063//Hunan Provincial Health High-Level Talent Scientific Research Project/ ; }, mesh = {*Cobalt/pharmacology ; *Biofilms/drug effects ; Animals ; *Osseointegration/drug effects ; *Macrophages/immunology/drug effects ; *Immunomodulation/drug effects ; *Prostheses and Implants ; *Titanium ; Disease Models, Animal ; Mice ; Methicillin-Resistant Staphylococcus aureus/drug effects ; Staphylococcal Infections/immunology/drug therapy ; Osteogenesis/drug effects ; Anti-Bacterial Agents/pharmacology/administration &amp; dosage ; }, abstract = {Treating bone infections and ensuring bone recovery is one of the major global problems facing modern orthopedics. Prolonged antibiotic use may increase the risk of antimicrobial resistance, and inflammation caused by biofilms can obstruct tissue healing, making bone infection treatment even more challenging. The optimal treatment strategy combines immune response modification to promote osteogenesis with effective bacterial infection removal that does not require long-term antibiotic use. A one-step plasma immersion ion implantation approach is used to create titanium alloy implants incorporating cobalt. According to experimental findings, cobalt-containing titanium implants exhibit improved antibacterial activity by efficiently disrupting biofilm formations and reducing Methicillin-resistant Staphylococcus aureus adherence by over 80%. Additionally, the implants exhibit superior anti-inflammatory and osseointegration properties. RNA sequencing analysis reveals the potential mechanism of Co[2+] in regulating the polarization of macrophages toward the anti-inflammatory M2 phenotype, which is crucial for creating an immune environment conducive to bone healing. Concurrently, these implants promote osteogenic differentiation while suppressing osteoclast activity, further supporting bone repair. Overall, without exogenous recombinant proteins or antibiotics, the implants effectively eradicate infections and expedite bone repair, offering a novel therapeutic strategy for complex skeletal diseases with clinical promise.}, }
@article {pmid39586542, year = {2025}, author = {Wu, J and Thompson, TP and O'Connell, NH and McCracken, K and Powell, J and Gilmore, BF and Dunne, CP and Kelly, SA}, title = {Extended-spectrum β-lactamase-producing bacteria from hospital wastewater pipes: isolation, characterization and biofilm control using common disinfectants.}, journal = {The Journal of hospital infection}, volume = {156}, number = {}, pages = {34-49}, doi = {10.1016/j.jhin.2024.11.013}, pmid = {39586542}, issn = {1532-2939}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Disinfectants/pharmacology ; *beta-Lactamases/metabolism ; *Wastewater/microbiology ; Ireland ; *Bacteria/drug effects/isolation &amp; purification ; Humans ; Microbial Sensitivity Tests ; Tertiary Care Centers ; Hospitals, Teaching ; Hospitals ; Bacterial Physiological Phenomena/drug effects ; }, abstract = {BACKGROUND: Hospital wastewater systems have been identified as reservoirs for antibiotic-resistant bacteria, with biofilms harbouring extended-spectrum β-lactamase (ESBL)-producing micro-organisms posing significant infection risk.<br><br>AIM: To study the antimicrobial susceptibility and biofilm control of ESBL-producing bacteria from wastewater pipes from a tertiary care teaching hospital in Ireland, which had experienced endemic infection outbreaks caused by ESBL-producing bacteria.<br><br>METHODS: Following isolation of ESBL producers on selective agar, antibiotic susceptibility profiles were determined for a number of antibiotics assessed for their ability to form biofilms. Biofilm eradication studies using the commercially available disinfectants bleach, Optizan&#x2122;, Virkon&#x2122; and Clinell&#x2122; were performed on selected isolates.<br><br>FINDINGS: ESBL-producing bacteria (N&#xa0;= 39 isolates) showed a high degree of resistance to &#x3b2;-lactams. Biofilm-forming ability ranged from non-adherent to strongly adherent and appeared to be source dependent, suggesting that the characteristics of the pipe environment played an important role in biofilm formation. All disinfectants showed effective biofilm eradication under suggested working conditions. Effectiveness was significantly reduced following reductions in concentration and contact time, with only Clinell&#x2122; showing significant biofilm reduction against all isolates at all concentrations and contact times tested. Of the chlorine-based formulations, Optizan&#x2122; frequently outperformed bleach at lower concentrations and treatment times. Biofilm eradication was strain dependent, with varying disinfectant response profiles observed from biofilms from different Stenotrophomonas maltophilia isolates.<br><br>CONCLUSIONS: This study highlights the high degree of ESBL-producing bacteria recovery from patient-facing hospital wastewater apparatus. Their ability to form resident biofilms and act as potential reservoirs of infection emphasizes the need for rigorous and effective infection control practices.}, }
@article {pmid39586513, year = {2025}, author = {Abdullah, HD and Kamal, I and Sabry, SA and Elghany, MA and Hakim Ramadan, AE}, title = {Effective tailoring of cefepime into bilosomes: A promising nanoplatform for enhancing oral absorption, extending half-life, and evaluating biocompatibility, antibacterial, anti-biofilm, anti-breast cancer activity, ex-vivo, and in-vivo studies.}, journal = {International journal of pharmaceutics}, volume = {668}, number = {}, pages = {125001}, doi = {10.1016/j.ijpharm.2024.125001}, pmid = {39586513}, issn = {1873-3476}, mesh = {*Anti-Bacterial Agents/administration &amp; dosage/pharmacology/chemistry/pharmacokinetics ; Animals ; *Cefepime/administration &amp; dosage/pharmacokinetics/pharmacology/chemistry ; *Biofilms/drug effects ; Humans ; Administration, Oral ; Half-Life ; Female ; *Liposomes ; Breast Neoplasms/drug therapy/pathology ; MCF-7 Cells ; Drug Liberation ; Antineoplastic Agents/administration &amp; dosage/chemistry/pharmacokinetics/pharmacology ; Rats ; Biological Availability ; Particle Size ; Male ; Rats, Sprague-Dawley ; Delayed-Action Preparations ; Nanoparticles/chemistry ; }, abstract = {The clinical implication of cefepime HCl (CEF) is compromised owing to restricted oral bioavailability and harmful adverse effects without any authorized oral formulation available. The present investigation provides an innovative sustained-release oral drug delivery strategy that tackles the challenges of limited oral bioavailability and prolongs the half-life of CEF. Accordingly, CEF was loaded into a bilosome, a liposome or noisome-based vesicle employing bile salt as a permeation enhancer. Despite its hydrophilic nature, the drug was effectively loaded into bilosomes. Nine various formulas were fabricated by a reverse phase evaporation method. The resulting vesicles increased the encapsulation efficiency (EE %) from 39.31 ± 0.03 % to 63.09 ± 0.01 %, drug loading capacity (DLC %) from 6.99 ± 0.25 to 42.91 ± 0.11 %, the particle size (PS) from 264 ± 13.52 nm to 405.40 ± 8.91 nm, and the polydispersity index (PDI) values ranged from 0.243 ± 0.040 to 0.430 ± 0.050. The zeta potential (ZP) changed from - 35.67 ± 3.73 mV to - 62.21 ± 2.21 mV. Further, the release profile exhibited dual release pattern within 24 h, with the percentage of release (CR %) expanding from 42 ± 0.13 % to 69.16 ± 0.09 %. The selected formula was found to be B3 with EE % = 56.61 ± 0.02 %, PS = 264 ± 13.52 nm, ZP = - 62.21 ± 2.21 mV, PDI = 0.430 ± 0.050, CR % = 52.94 ± 0.06 %, and IC50 of 3.4 ± 0.40 µg/ml against MCF-7 cells with scattered spherical non-agglomerated vesicles. Additionally, it exhibited higher anti-MRSA biofilm, relative bioavailability (5.1 fold), and antimicrobial capacity against P. aeruginosa, E. coli, B. subtilis, and S. aureus compared to pure CEF. Our data demonstrate that bilosome is a powerful nanocarrier for oral delivery of cefepime, boosting its biological impacts and pharmacokinetic profile.}, }
@article {pmid39586337, year = {2025}, author = {Patra, S and Saha, S and Singh, R and Tomar, N and Gulati, P}, title = {Biofilm battleground: Unveiling the hidden challenges, current approaches and future perspectives in combating biofilm associated bacterial infections.}, journal = {Microbial pathogenesis}, volume = {198}, number = {}, pages = {107155}, doi = {10.1016/j.micpath.2024.107155}, pmid = {39586337}, issn = {1096-1208}, mesh = {*Biofilms/growth &amp; development ; *Quorum Sensing ; Humans ; *Bacterial Infections/microbiology ; *Bacteria/genetics ; Anti-Bacterial Agents/pharmacology ; Bacterial Physiological Phenomena ; Extracellular Polymeric Substance Matrix/metabolism ; }, abstract = {A biofilm is a complex aggregation of microorganisms, either of the same or different species, that adhere to a surface and are encased in an extracellular polymeric substances (EPS) matrix. Quorum sensing (QS) and biofilm formation are closely linked, as QS genes regulate the development, maturation, and breakdown of biofilms. Inhibiting QS can be utilized as an effective approach to combat the impacts of biofilm infection. The impact of biofilms includes chronic infections, industrial biofouling, infrastructure corrosion, and environmental contamination as well. Therefore, a deep understanding of biofilms is crucial for enhancing public health, advancing industrial processes, safeguarding the environment, and deepening our knowledge of microbial life as well. This review aims to offer a comprehensive examination of challenges posed by bacterial biofilms, contemporary approaches and strategies for effectively eliminating biofilms, including the inhibition of quorum sensing pathways, while also focusing on emerging technologies and techniques for biofilm treatment. In addition, future research is projected to target the challenges associated with the bacterial biofilms, striving to develop new approaches and improve existing strategies for their effective control and eradication.}, }
@article {pmid39586149, year = {2025}, author = {Hajiaghaalizadeh, M and Sheikharabi, M and Jazi, MS and Alhashem, R and Hosseini, SS}, title = {Anti-biofilm activity of carvacrol-thymoquinone nanocarriers on vulvovaginal candidiasis isolates.}, journal = {Diagnostic microbiology and infectious disease}, volume = {111}, number = {2}, pages = {116606}, doi = {10.1016/j.diagmicrobio.2024.116606}, pmid = {39586149}, issn = {1879-0070}, mesh = {*Biofilms/drug effects ; *Candidiasis, Vulvovaginal/microbiology/drug therapy ; *Antifungal Agents/pharmacology ; Humans ; *Cymenes/pharmacology ; Female ; *Microbial Sensitivity Tests ; *Benzoquinones/pharmacology/chemistry ; *Nanoparticles/chemistry ; *Candida albicans/drug effects ; Drug Carriers/chemistry ; Candida glabrata/drug effects ; Monoterpenes/pharmacology/chemistry ; Candida/drug effects ; }, abstract = {Given the recurrent nature of vulvovaginal candidiasis (VVC), the restricted availability of effective antifungal agents, and the recent rise in drug resistance, this study sought to assess the antifungal efficacy of carvacrol-thymoquinone delivered via a nanocarrier on Candida isolates obtained from patients with VVC. Isolates were identified using phenotypic and genotypic methods. Nanocarriers were synthesized using the thin-film hydration method. The antifungal activity of carvacrol-thymoquinone was evaluated using the broth microdilution method (CLSIM27-A3). The impact of nanocarriers on the biofilm formation capabilities of Candida isolates was assessed using the MTT assay. Data were analyzed using the Mann-Whitney U test. The nanocarrier exhibited a spherical morphology with a diameter measuring 50 nm. The nano-formulated drug combination could inhibit biofilm formation in C. albicans at half the minimum inhibitory concentration and in C. glabrata at the minimum inhibitory concentration. Our results suggest that the carvacrol-thymoquinone nanocarrier can be studied further in vivo for potential use in the treatment of recurrent VVC.}, }
@article {pmid39585926, year = {2024}, author = {Prentice, JA and Kasivisweswaran, S and van de Weerd, R and Bridges, AA}, title = {Biofilm dispersal patterns revealed using far-red fluorogenic probes.}, journal = {PLoS biology}, volume = {22}, number = {11}, pages = {e3002928}, pmid = {39585926}, issn = {1545-7885}, support = {R00 AI158939/AI/NIAID NIH HHS/United States ; }, mesh = {*Biofilms/growth &amp; development ; *Vibrio cholerae/physiology ; *Fluorescent Dyes ; Bacterial Proteins/metabolism/genetics ; }, abstract = {Bacteria frequently colonize niches by forming multicellular communities called biofilms. To explore new territories, cells exit biofilms through an active process called dispersal. Biofilm dispersal is essential for bacteria to spread between infection sites, yet how the process is executed at the single-cell level remains mysterious due to the limitations of traditional fluorescent proteins, which lose functionality in large, oxygen-deprived biofilms. To overcome this challenge, we developed a cell-labeling strategy utilizing fluorogen-activating proteins (FAPs) and cognate far-red dyes, which remain functional throughout biofilm development, enabling long-term imaging. Using this approach, we characterize dispersal at unprecedented resolution for the global pathogen Vibrio cholerae. We reveal that dispersal initiates at the biofilm periphery and approximately 25% of cells never disperse. We define novel micro-scale patterns that occur during dispersal, including biofilm compression during cell departure and regional heterogeneity in cell motions. These patterns are attenuated in mutants that reduce overall dispersal or that increase dispersal at the cost of homogenizing local mechanical properties. Collectively, our findings provide fundamental insights into the mechanisms of biofilm dispersal, advancing our understanding of how pathogens disseminate. Moreover, we demonstrate the broad applicability of FAPs as a powerful tool for high-resolution studies of microbial dynamics in complex environments.}, }
@article {pmid39584338, year = {2024}, author = {Yang, C and Ran, L and Yang, Z and Hu, H and Wei, W and Yang, H and Zhu, M and Yu, Y and Fu, L and Chen, H}, title = {[Screening of active components in Chinese medicine with effects on Escherichia coli biofilm based on molecular docking].}, journal = {Sheng wu gong cheng xue bao = Chinese journal of biotechnology}, volume = {40}, number = {11}, pages = {4120-4137}, doi = {10.13345/j.cjb.240113}, pmid = {39584338}, issn = {1872-2075}, mesh = {*Biofilms/drug effects ; *Escherichia coli/drug effects/genetics/metabolism ; *Molecular Docking Simulation ; *Drugs, Chinese Herbal/pharmacology/chemistry ; Tannins/pharmacology/chemistry ; Cinnamates/pharmacology/chemistry/metabolism ; Benzofurans/pharmacology/chemistry ; Depsides/pharmacology/chemistry/metabolism ; Rosmarinic Acid ; Anti-Bacterial Agents/pharmacology/chemistry ; Escherichia coli Proteins/metabolism/genetics ; Medicine, Chinese Traditional ; }, abstract = {By targeting the key gene csgD involved in the biofilm formation of Escherichia coli, we employed molecular docking and molecular dynamics simulation to screen the active components of Chinese medicine with inhibitory effects on the biofilm formation from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP). After the anti-biofilm properties of the active components were validated in vitro, data-independent acquisition (DIA) proteomics was employed to further identify the differential proteins involved in interfering with the biofilm formation of Escherichia coli. The mechanisms of inhibition were explored with consideration to the phenotype. Through virtual screening, we identified four candidate active components, including tannic acid, narirutin, salvianolic acid B, and rosmarinic acid. Among them, tannic acid demonstrated significant inhibitory effect on the biofilm formation of E. coli. The analysis of differential proteins, combined with relevant phenotype validation, suggested that tannic acid primarily affected E. coli by intervening in pilus assembly, succinic acid metabolism, and the quorum sensing system. This study provided a lead compound for the development of new drugs against biofilm-associated infections in the future.}, }
@article {pmid39583991, year = {2024}, author = {Gomez-Lopez, A and Fernandez-Fernandez, C}, title = {Molecular characterization of gliotoxin synthesis in a biofilm model of Aspergillus fumigatus.}, journal = {Biofilm}, volume = {8}, number = {}, pages = {100238}, pmid = {39583991}, issn = {2590-2075}, abstract = {Mycelial growth as biofilm structures and the activation of secondary metabolism leading to the release of low-molecular-weight molecules (known as secondary metabolites), are among the previously described strategies used by the filamentous fungi Aspergillus fumigatus to adapt and survive. Our study unveils that A. fumigatus strains can activate mechanisms linked to the production of gliotoxin, a crucial metabolite for Aspergillus, in the established in vitro biofilm model. Gliotoxin production exhibits strain- and time-dependent patterns and is associated -in a coordinated manner-with the expression levels of several genes involved in its regulation and synthesis. The transcriptional study of some of these genes by qPCR shows temporal inter-strain differences, which correlate with those obtained when evaluating the amounts of metabolites produced. Given that A. fumigatus forms biofilm structures within the site of infection, understanding the regulation of gliotoxin biosynthesis may have a role in the evolution of Aspergillus infection and guide diagnostic and treatment strategies.}, }
@article {pmid39582781, year = {2024}, author = {Wen, T and Zhao, Y and Fu, Y and Chen, Y and Li, X and Shi, C and Xian, D and Zhao, W and Yang, D and Lu, C and Wu, C and Pan, X and Quan, G}, title = {"On-demand" nanosystem-integrated microneedles for amplified triple therapy against recalcitrant bacteria and biofilm growth.}, journal = {Materials today. Bio}, volume = {29}, number = {}, pages = {101327}, pmid = {39582781}, issn = {2590-0064}, abstract = {Phototherapy has emerged to eradicate recalcitrant bacteria without causing drug resistance, but it is often accompanied by considerable limitations owing to a high tolerance of recalcitrant bacteria to heat and oxidative damage, leading to low efficiency of monotherapy and unwanted side effects. Assuming that employing antimicrobial peptides (AMPs) to disrupt bacterial membranes could reduce bacterial tolerance, a multifunctional "on-demand" nanosystem based on zeolitic imidazolate framework-8 (ZIF-8) with metal ions for intrinsic antibacterial activity was constructed to potently kill methicillin-resistant Staphylococcus aureus (MRSA). Then, microneedles (MNs) were used to transdermally deliver the ZIF-8-based nanosystem for localized skin infection. After MNs insertion, the nanoplatform could specifically deliver the loaded therapeutic components to bacterial infection sites through employing hyaluronic acid (HA) as a capping agent, thus realizing the "on-demand" payload release triggered by excess hyaluronidase secreted by MRSA. The prepared nanosystem and MNs were confirmed to exert an amplified triple therapy originating from membranolytic effect, phototherapy, and ion therapy, thus displaying a powerful bactericidal and MRSA biofilm destruction ability. This intelligent antimicrobial strategy may bring a dawn of hope for eradicating multidrug-resistant bacteria and biofilms.}, }
@article {pmid39581889, year = {2024}, author = {Zaffar, R and Nazir, R and Hameed, J and Rather, MA}, title = {Biofilm and Extracellular Polymeric Substance (EPS) synergy: Revealing Staphylococcus's role in nitrate bioremediation.}, journal = {World journal of microbiology &amp; biotechnology}, volume = {40}, number = {12}, pages = {391}, pmid = {39581889}, issn = {1573-0972}, support = {SR/WOS-A/LS-232/2018//Department of Science and Technology, Ministry of Science and Technology, India/ ; }, mesh = {*Biofilms/growth &amp; development ; *Biodegradation, Environmental ; *Staphylococcus/metabolism/isolation &amp; purification/growth &amp; development/physiology ; *Extracellular Polymeric Substance Matrix/metabolism ; *Nitrates/metabolism ; India ; Lakes/microbiology ; Denitrification ; }, abstract = {Staphylococcus species, traditionally associated with pathogenicity, are gaining attention for their role in environmental bioremediation, particularly nitrate reduction, which is crucial for mitigating eutrophication. In this study, denitrifying, biofilm-forming Staphylococcus strains were isolated from Dal Lake, India. Biofilm formation was quantified using a microtiter plate assay, and extracellular polymeric substances (EPS) were measured by dry weight. Statistical analysis revealed a strong positive correlation between EPS production and nitrate removal efficiency (r = 0.96, p < 0.001), with EPS accounting for 92% of the variance in nitrate reduction (R[2] = 0.92). Among the isolates, Staphylococcus epidermidis exhibited the highest nitrate reduction at 87% (SD = 2.3%), followed by S. succinus at 83% (SD = 2.1%), S. equorum at 77% (SD = 2.5%), and Staphylococcus sp. at 70% (SD = 2.8%). The consistency of these findings was confirmed by boxplot analysis, and the regression model's robustness was validated by residual plots showing minimal systematic error. This research work provides the first evidence of the nitrate-reducing capabilities of these Staphylococcus species, underscoring their potential in sustainable bioremediation strategies for aquatic environments. The significant correlation between EPS production and nitrate reduction highlights the critical role of biofilms in enhancing microbial remediation processes. The study not only advances the understanding of Staphylococcus in non-pathogenic roles but also suggests that these strains could be pivotal in bioremediation technologies, potentially influencing future environmental management practices.}, }
@article {pmid39581435, year = {2024}, author = {Ono, K and Hayashi, JI and Suzuki, Y and Yamashita, M and Nishikawa, K and Higuchi, N and Goto, R and Ohno, T and Nishida, E and Yamamoto, G and Kikuchi, T and Hasegawa, Y and Mitani, A}, title = {Photodynamic disruption of a polymicrobial biofilm of two periodontal species using indocyanine green-loaded nanospheres.}, journal = {Photodiagnosis and photodynamic therapy}, volume = {50}, number = {}, pages = {104421}, doi = {10.1016/j.pdpdt.2024.104421}, pmid = {39581435}, issn = {1873-1597}, mesh = {*Indocyanine Green/pharmacology ; *Photochemotherapy/methods ; *Biofilms/drug effects ; *Porphyromonas gingivalis/drug effects ; *Nanospheres ; *Photosensitizing Agents/pharmacology ; *Streptococcus gordonii/drug effects ; Anti-Bacterial Agents/pharmacology ; Chitosan/pharmacology ; Lasers, Semiconductor ; Humans ; }, abstract = {OBJECTIVE: Antimicrobial photodynamic therapy (aPDT) is considered a potential treatment for biofilm infections, which have become an increasing health issue because of the rise in antimicrobial resistance. This study aimed to evaluate the bactericidal effect of aPDT using indocyanine green-loaded nanospheres with chitosan coating (ICG-Nano/c) against polymicrobial periodontal biofilms.<br><br>METHODS: Composite biofilms of Porphyromonas gingivalis and Streptococcus gordonii were constructed in 96-well plates, and aPDT with ICG-Nano/c and an 810 nm diode laser was performed either by direct irradiation or transmitting irradiation through a 3-mm-thick gingival model. The efficacy of ICG-Nano/c-based aPDT was compared with antibiotics (minocycline and amoxicillin). Additionally, attenuated aPDT under sublethal conditions was used to investigate gene expression related to the antioxidant response (oxyR and sod of P. gingivalis) and biofilm formation via quorum sensing (luxS of both species) with real-time polymerase chain reaction.<br><br>RESULTS: ICG-Nano/c-based aPDT significantly reduced the bacterial load in the biofilm, achieving at least a 2 log10 reduction in colony-forming units within 5 min for both irradiation methods. After 6 h of treatment, the bactericidal effects of aPDT and antibiotics were similar, but after 32 h, antibiotics were more effective, particularly against P. gingivalis. Attenuated aPDT showed a slight increase in sod expression in P. gingivalis, while luxS expression decreased in both bacteria.<br><br>CONCLUSION: The ICG-Nano/c-based aPDT system exerted a certain degree of bactericidal activity against a composite biofilm of periodontal bacteria. Therefore, it has potential as an alternative option or adjunctive therapy to conventional antibiotics in periodontal treatment.}, }
@article {pmid39580490, year = {2024}, author = {Korshoj, LE and Kielian, T}, title = {Bacterial single-cell RNA sequencing captures biofilm transcriptional heterogeneity and differential responses to immune pressure.}, journal = {Nature communications}, volume = {15}, number = {1}, pages = {10184}, pmid = {39580490}, issn = {2041-1723}, support = {F32 NS126302/NS/NINDS NIH HHS/United States ; 3P01AI083211//U.S. Department of Health &amp; Human Services | NIH | National Institute of Allergy and Infectious Diseases (NIAID)/ ; P30 CA036727/CA/NCI NIH HHS/United States ; F32NS126302//U.S. Department of Health &amp; Human Services | NIH | National Institute of Neurological Disorders and Stroke (NINDS)/ ; P01 AI083211/AI/NIAID NIH HHS/United States ; P20 GM103427/GM/NIGMS NIH HHS/United States ; }, mesh = {*Biofilms/growth &amp; development ; *Staphylococcus aureus/genetics/physiology/immunology ; *Single-Cell Analysis/methods ; *Sequence Analysis, RNA/methods ; Gene Expression Regulation, Bacterial ; Gene Regulatory Networks ; Animals ; Virulence/genetics ; Humans ; }, abstract = {Biofilm formation is an important mechanism of survival and persistence for many bacterial pathogens. These multicellular communities contain subpopulations of cells that display metabolic and transcriptional diversity along with recalcitrance to antibiotics and host immune defenses. Here, we present an optimized bacterial single-cell RNA sequencing method, BaSSSh-seq, to study Staphylococcus aureus diversity during biofilm growth and transcriptional adaptations following immune cell exposure. BaSSSh-seq captures extensive transcriptional heterogeneity during biofilm compared to planktonic growth. We quantify and visualize transcriptional regulatory networks across heterogeneous biofilm subpopulations and identify gene sets that are associated with a trajectory from planktonic to biofilm growth. BaSSSh-seq also detects alterations in biofilm metabolism, stress response, and virulence induced by distinct immune cell populations. This work facilitates the exploration of biofilm dynamics at single-cell resolution, unlocking the potential for identifying biofilm adaptations to environmental signals and immune pressure.}, }
@article {pmid39579939, year = {2025}, author = {Semeshchenko, D and Veiga, MF and Visus, M and Farinati, A and Huespe, I and ,  and Buttaro, MA and Slullitel, PA}, title = {Povidone-iodine and silver nitrate are equally effective in eradicating staphylococcal biofilm grown on a titanium surface: an in-vitro analysis.}, journal = {The Journal of hospital infection}, volume = {155}, number = {}, pages = {185-191}, doi = {10.1016/j.jhin.2024.11.012}, pmid = {39579939}, issn = {1532-2939}, mesh = {*Povidone-Iodine/pharmacology ; *Titanium/pharmacology ; *Silver Nitrate/pharmacology ; *Biofilms/drug effects ; *Staphylococcus aureus/drug effects ; Humans ; Anti-Bacterial Agents/pharmacology ; Microbial Sensitivity Tests ; Colony Count, Microbial ; Methicillin-Resistant Staphylococcus aureus/drug effects ; }, abstract = {BACKGROUND: There is no consensus on the irrigation solution and concentration that should be used when performing a debridement, antibiotics, and implant retention (DAIR) surgery.<br><br>AIM: To determine the minimum biofilm eradication concentration (MBEC) of five antibacterial solutions and to compare their efficacies in eradicating staphylococcal biofilm embedded on a titanium surface.<br><br>METHODS: Meticillin-sensitive Staphylococcus aureus (MSSA) and meticillin-resistant S.&#xa0;aureus (MRSA) ATCC standard strains were grown over porous Ti-6Al-4V acetabular screw-caps. Antibacterial solutions were povidone-iodine, rifampicin, silver nitrate, copper sulphate, and chlorhexidine. MBEC values were calculated for MSSA and MRSA. After 24&#xa0;h, screw-caps were exposed for 3&#xa0;min to each solution. Bacterial separation from each specimen was performed with vortex agitation and footprint on agar plate in triplicate. Colony forming units (cfu) were counted pre- and post-agitation, and the delta of cfu/mL was calculated for each solution. A threefold log reduction in cfu was considered a measure of solution efficacy. Comparison between groups was made with Fisher's test.<br><br>FINDINGS: MBEC values for MSSA and MRSA, respectively, were as follows: 8000&#xa0;&#x3bc;g/mL and 16,000&#xa0;&#x3bc;g/mL for povidone-iodine; 64&#xa0;&#x3bc;g/mL and 128&#xa0;&#x3bc;g/mL for rifampicin; 10,000&#xa0;&#x3bc;g/mL and 5120&#xa0;&#x3bc;g/mL for silver nitrate; 900&#xa0;&#x3bc;g/mL and 900&#xa0;&#x3bc;g/mL for copper sulphate; 16&#xa0;&#x3bc;g/mL and 32&#xa0;&#x3bc;g/mL for chlorhexidine. Rifampicin, copper sulphate and chlorhexidine were ineffective against MSSA and MRSA biofilm compared with povidone-iodine (P<0.01) and silver nitrate (P=0.015) that had a delta cfu reduction >8 log. Povidone-iodine and silver nitrate showed negative footprints without visible MSSA (P=0.005) and MRSA (P=0.014).<br><br>CONCLUSIONS: Povidone-iodine and silver nitrate were the only irrigating solutions capable of eradicating at least 99.9% of 24-h biofilm.}, }
@article {pmid39579902, year = {2024}, author = {Díaz-Muñiz, CA and Nieto-Delgado, C and IIhan, ZE and Rittmann, BE and Ontiveros-Valencia, A}, title = {Lead removal by its precipitation with biogenic sulfide in a membrane biofilm reactor.}, journal = {The Science of the total environment}, volume = {957}, number = {}, pages = {177578}, doi = {10.1016/j.scitotenv.2024.177578}, pmid = {39579902}, issn = {1879-1026}, mesh = {*Lead/metabolism ; *Biofilms ; *Sulfides ; *Bioreactors/microbiology ; *Water Pollutants, Chemical/metabolism ; Waste Disposal, Fluid/methods ; Membranes, Artificial ; Chemical Precipitation ; }, abstract = {We evaluated the feasibility of using hydrogen (H2)-based membrane biofilm reactors (MBfRs) to promote the growth of hydrogenotrophic sulfate-reducing bacteria (SRB) to remove lead (Pb) through its precipitation as lead sulfide (PbS) via biogenic sulfide (HS[-]) production. Two MBfRs (R1 and R2) were set-up to treat synthetic water rich in sulfate (SO4[2-]) (585 mg/L) and Pb (50, 100, or 250 mg/L). R1 had one influent that had the Pb and synthetic media mixed together; R2 received the Pb solution and synthetic medium through separate influent lines. Oxygen (O2) and nitrate (NO3[-]) were secondary electron acceptors in R1 and R2, respectively. R1 and R2 produced enough HS[-] (> 73 mg/L) to precipitate Pb, and Pb removal reached >97 %. Chemical equilibrium calculations identified which solids were possible in each stage of operation. Precipitation of Pb with phosphate (PO4[3-]) occurred in the feed solution in R1, but phosphate precipitation was avoided in the R2 influent. The predominant Pb precipitate inside R2 was PbS, which was confirmed by SEM-EDX analysis. The microbial communities of R1 and R2 were dominated by two SRB - Desulfomicrobium and Fusibacter - along with sulfur oxidizer Thiovirga and denitrifier Thauera. Although the presence of electron acceptors other than SO4[2-] enabled other respiratory metabolisms, they did not prevent SO4[2-] reduction to HS[-] or the precipitation of PbS.}, }
@article {pmid39579496, year = {2025}, author = {He, X and Sheng, X and Yao, X and Wang, Y and Zhang, L and Wang, H and Yuan, L}, title = {The anti-biofilm effect of α-amylase/glycopolymer-decorated gold nanorods.}, journal = {Colloids and surfaces. B, Biointerfaces}, volume = {246}, number = {}, pages = {114393}, doi = {10.1016/j.colsurfb.2024.114393}, pmid = {39579496}, issn = {1873-4367}, mesh = {*Biofilms/drug effects ; *Gold/chemistry/pharmacology ; *Nanotubes/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; *Pseudomonas aeruginosa/drug effects ; *alpha-Amylases/antagonists &amp; inhibitors/metabolism/chemistry ; *Microbial Sensitivity Tests ; }, abstract = {The continuous evolution of bacteria and the formation of biofilm have exacerbated resistance issues, highlighting the urgent need for new antibacterial materials. In this study, L-fucose was polymerized to synthesize thiolated poly(2-(L-fucose) ethyl methacrylate) (PFEMA-SH), which was subsequently co-modified with α-amylase onto gold nanorods (GNR) to prepare the antibacterial nanoparticle composite, GNR-Amy-PFEMA (G-A-P). These nanomaterials exhibit both photothermal and enzymatic properties, enabling G-A-P to effectively sterilize and disperse biofilm. Under near-infrared light irradiation, the temperature of G-A-P composite increases significantly, leading to bacterial cell damage and biofilm disruption. The G-A-P composite demonstrated nearly 100 % eradication of planktonic bacteria after 5 min of irradiation and achieved a 70.9 % reduction in mature biofilm biomass, with a 3.37-log decrease in the number of bacteria within the biofilm. These composites display strong antimicrobial activity and hold great potential for the removal of Pseudomonas aeruginosa biofilm. Furthermore, the ability of G-A-P to reduce biofilm formation without the use of traditional antibiotics suggests that it may offer an antibiotic-free alternative for managing biofilm-related infections.}, }
@article {pmid39579303, year = {2024}, author = {Chen, YY and Liu, ZS and Chen, BY and Tam, HM and Shia, WY and Yu, HH and Chen, PW}, title = {Effects of Heat-Killed Probiotic Strains on Biofilm Formation, Transcription of Virulence-Associated Genes, and Prevention of UTIs in Mice.}, journal = {Probiotics and antimicrobial proteins}, volume = {}, number = {}, pages = {}, pmid = {39579303}, issn = {1867-1314}, support = {YSHV 112-07//Taipei Veterans General Hospital/ ; YSHV 112-07//Taipei Veterans General Hospital/ ; grants 112-2313-B-005-037//National Science and Technology Council/ ; }, abstract = {Urinary tract infections (UTIs) pose a substantial healthcare challenge, exacerbated by the biofilm-forming abilities and antibiotic resistance of uropathogens. This study investigated the inhibition of biofilm formation (anti-biofilm) and dispersion of pre-established biofilm properties of 18 heat-killed probiotics and their supernatants against four antibiotic-resistant uropathogens: UPEC, Klebsiella pneumoniae (KP), Methicillin-resistant Escherichia coli (MREC), and Methicillin-resistant Staphylococcus pseudintermedius (MRSP). Supernatants from 14 probiotic strains significantly (P < 0.001) inhibited UPEC biofilm formation, reducing it by 20-80%, and also showed promise in removing existing biofilms by 10-60% (P < 0.001). Eight strains significantly (P < 0.05 to < 0.001) inhibited MREC biofilm formation, with four strains achieving 50-80% dispersion. Seventeen strains of heat-killed probiotics directly inhibited UPEC biofilm formation by 10-60% (P < 0.05 to < 0.001), but were less effective against MREC and MRSP (10-50% reduction; P < 0.05 to < 0.001) and had limited impact on KP (10% reduction; P < 0.05 to < 0.001). Notably, heat-killed probiotic like LGA, LGC, LGD, TP-8, and TP-4 showed the most significant inhibitory and dispersion of biofilm activity. RT-qPCR analysis further revealed these inactivated probiotics downregulated genes associated with pili and biofilm formation (fimA, csgA) and upregulated genes linked to quorum sensing (luxS, qseBC, sdiA). Therefore, these findings suggest that paraprobiotic treatment could inhibit the formation of pili and biofilms and promote biofilm dispersion. In an animal model, mice given paraprobiotic formulations I (16 strains) and II (a specific mixture) for 2 weeks showed reduced urinary bacterial load (P < 0.05). Paraprobiotic I notably reduced morbidity from bacteriuria (> 10[5] CFU/ml) by 5 to 30% within the first 5 days post-infection compared to placebo. These findings highlight the potential of specific heat-killed probiotics in combating biofilms and preventing UTIs.}, }
@article {pmid39578969, year = {2024}, author = {Srivastava, N and Deka, S and Kumar, L}, title = {A dual-action strategy of propenyl guaethol: pilY-mediated biofilm inhibition and augmenting aminoglycoside antibiofilm activity against Pseudomonas aeruginosa through in vitro and in silico studies.}, journal = {Journal of biomolecular structure &amp; dynamics}, volume = {}, number = {}, pages = {1-16}, doi = {10.1080/07391102.2024.2429021}, pmid = {39578969}, issn = {1538-0254}, abstract = {Flavoring compounds are natural or synthetic substances that enhance the food flavor. Research studies have demonstrated that flavoring compounds may have biological activities. In food industry, P. aeruginosa dominates spoilage and contamination of food products. Human exposure to P. aeruginosa may lead to serious infections. P. aeruginosa forms complex biofilms with extracellular slime matrix, providing protection against antimicrobial agents. The present study investigates the role of a flavouring food additive, propenyl guaethol (PG) against Pseudomonas aeruginosa biofilms. Our results demonstrate a significant impact of PG on biofilm forming ability, bacterial attachment, and motility phenotypes. The polystyrene tube assay demonstrates notable inhibition of biofilm formation by P. aeruginosa at 50 and 25 µg/ml (p < 0.01). PG showed marked inhibition of biofilms in combination with gentamicin, kanamycin, and streptomycin. Additionally, PG inhibits twitching, swarming, and swimming motility of P. aeruginosa (p < 0.01). Scanning electron microscopy, fluorescent microscopy, and light microscopy showed thinner biofilms with low exopolysaccharide matrix (EPS) in the presence of PG. Moreover, the role of PG was also evaluated using molecular docking and molecular dynamics simulation to understand the interaction of PG with bacterial type-IV pili subunit, PilY1. PG showed favourable interactions and stable complex formation with type-IV pili subunit (PilY1). The present study highlights the antibiofilm properties of PG, suggesting its potential as a biofilm control flavoring compound.}, }
@article {pmid39574716, year = {2024}, author = {Kivimaki, SE and Dempsey, S and Camper, C and Tani, JM and Hicklin, IK and Blaby-Haas, CE and Brown, AM and Melville, SB}, title = {Type IV pili-associated secretion of a biofilm matrix protein from Clostridium perfringens that forms intermolecular isopeptide bonds.}, journal = {bioRxiv : the preprint server for biology}, volume = {}, number = {}, pages = {}, pmid = {39574716}, issn = {2692-8205}, support = {R21 AI109391/AI/NIAID NIH HHS/United States ; }, abstract = {Clostridium perfringens is a Gram-positive anaerobic spore-forming bacterial pathogen of humans and animals. C. perfringens also produces type IV pili (T4P) and has two complete sets of T4P-associated genes, one of which has been shown to produce surface pili needed for cell adherence. One hypothesis about the role of the other set of T4P genes is that they could comprise a system analogous to the type II secretion systems (TTSS) found in Gram-negative bacteria, which is used to export folded proteins from the periplasm through the outer membrane to the extracellular environment. Gram-positive bacteria have a similar secretion barrier in the thick peptidoglycan (PG) layer, which blocks secretion of folded proteins >25 kD. To determine if the T4P-associated genes comprise a Gram-positive TTSS, the secretome of mutants lacking type IV pilins were examined and a single protein, a von Willebrand A domain containing protein BsaC (CPE0517) was identified as being dependent on PilA3 for secretion. BsaC is in an operon with a signal peptidase and two putative biofilm matrix proteins with homology to Bacillus subtilis TasA. One of these proteins, BsaA, was shown by another group to produce high mol wt oligomers. We analyzed BsaA monomer interactions with de novo modeling, which projected that the monomers formed isopeptide bonds as part of a donor strand exchange process. Mutations in residues predicted to form the isopeptide bonds led to loss of oligomerization, supporting the predicted bond formation process. Phylogenetic analysis showed the BsaA family of proteins are widespread among bacteria and archaea but only a subset are predicted to form isopeptide bonds.}, }
@article {pmid39574578, year = {2024}, author = {Keim, K and Bhattacharya, M and Crosby, HA and Jenul, C and Mills, K and Schurr, M and Horswill, A}, title = {Polymicrobial interactions between Staphylococcus aureus and Pseudomonas aeruginosa promote biofilm formation and persistence in chronic wound infections.}, journal = {bioRxiv : the preprint server for biology}, volume = {}, number = {}, pages = {}, pmid = {39574578}, issn = {2692-8205}, support = {I01 BX002711/BX/BLRD VA/United States ; P01 AI083211/AI/NIAID NIH HHS/United States ; }, abstract = {Chronic, non-healing wounds are a leading cause of prolonged patient morbidity and mortality due to biofilm- associated, polymicrobial infections. Staphylococcus aureus and Pseudomonas aeruginosa are the most frequently co-isolated pathogens from chronic wound infections. Competitive interactions between these pathogens contribute to enhanced virulence, persistence, and antimicrobial tolerance. P. aeruginosa utilizes the extracellular proteases LasB, LasA, and AprA to degrade S. aureus surface structures, disrupt cellular physiology, and induce cell lysis, gaining a competitive advantage during co-infection. S. aureus evades P. aeruginosa by employing aggregation mechanisms to form biofilms. The cell wall protein SasG is implicated in S. aureus biofilm formation by facilitating intercellular aggregation upon cleavage by an extracellular protease. We have previously shown that proteolysis by a host protease can induce aggregation. In this study, we report that P. aeruginosa proteases LasA, LasB, and AprA cleave SasG to induce S. aureus aggregation. We demonstrate that SasG contributes to S. aureus biofilm formation in response to interactions with P. aeruginosa proteases by quantifying aggregation, SasG degradation, and proteolytic kinetics. Additionally, we assess the role of SasG in influencing S. aureus biofilm architecture during co-infection in vivo, chronic wound co-infections. This work provides further knowledge of some of the principal interactions that contribute to S. aureus persistence within chronic wounds co-infected with P. aeruginosa, and their impact on healing and infection outcomes.}, }
@article {pmid39574143, year = {2024}, author = {MacLean, J and Bartholomäus, A and Blukis, R and Liebner, S and Wagner, D}, title = {Metatranscriptomics of microbial biofilm succession on HDPE foil: uncovering plastic-degrading potential in soil communities.}, journal = {Environmental microbiome}, volume = {19}, number = {1}, pages = {95}, pmid = {39574143}, issn = {2524-6372}, support = {02WPL1449D//Bundesministerium f&#xfc;r Bildung und Forschung/ ; I-044-16-0//Helmholtz-Gemeinschaft/ ; }, abstract = {BACKGROUND: Although plastic pollution is increasing worldwide, very little is known about the microbial processes that take place once plastic debris is incorporated into the soil matrix. In this study, we conducted the first metatranscriptome analysis of polyethylene (PE)-associated biofilm communities in highly polluted landfill soil and compared their gene expression to that of a forest soil community within a 53-day period.<br><br>RESULTS: Our findings indicate that the microbial population present in soil contaminated with plastic debris is predisposed to both inhabit and degrade plastic surfaces. Surprisingly, the microbial community from undisturbed forest soil contained a diverse array of plastic-associated genes (PETase, alkB, etc.), indicating the presence of an enzymatic machinery capable of plastic degradation. Plastic-degrading taxa were upregulated in the early stages of biofilm formation. During the maturation of the biofilm, the alkB1/alkM transcripts, which encode PE-degrading enzymes, and transporters such as fadL, livG, livF, livH, and livM were upregulated, along with transcripts associated with the fatty acid &#x3b2;-oxidation pathway.<br><br>CONCLUSIONS: In this study, we address the underlying patterns of gene expression during biofilm development in a PE-associated plastisphere in soil and address the pressing question of whether natural microbial communities have the potential to biodegrade petrochemical-based plastic in the soil environment.}, }
@article {pmid39572965, year = {2024}, author = {Shrestha, S and Basnet, A and Maharjan, R and Basnet, B and Joshi, P}, title = {Biofilm-Associated Multidrug-Resistant and Methicillin-Resistant Staphylococcus aureus Infections.}, journal = {Journal of Nepal Health Research Council}, volume = {22}, number = {2}, pages = {410-418}, pmid = {39572965}, issn = {1999-6217}, mesh = {*Biofilms/drug effects ; Humans ; Cross-Sectional Studies ; Female ; Male ; Child, Preschool ; *Methicillin-Resistant Staphylococcus aureus/drug effects/isolation &amp; purification ; Nepal/epidemiology ; Infant ; *Staphylococcal Infections/microbiology/epidemiology/drug therapy ; *Drug Resistance, Multiple, Bacterial ; Child ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; Adolescent ; Staphylococcus aureus/drug effects/isolation &amp; purification ; Prevalence ; }, abstract = {BACKGROUND: The ability of Staphylococcus aureus to form biofilmsâ€"architectural complexes that cause chronic and recalcitrant infectionsâ€"along with its notorious variant, methicillin-resistant Staphylococcus aureus (MRSA), leads to multidrug-resistant (MDR) infections that are challenging to treat with antibiotics. This cross-sectional study investigated the prevalence of S. aureus infections in Kanti Children’s Hospital and characterized the antibiograms of MDR, MRSA, and biofilm-forming strains, along with their coexistence.<br><br>METHODS: &#xa0;S. aureus strains were isolated and identified from clinical samples and tested for antibiograms following standard microbiology guidelines. MDR strains were non-susceptible to at least one agent in three antimicrobial categories, whereas MRSA strains were cefoxitin-resistant. The microtiter plate method was used to detect biofilms. Statistical analyses were performed using SPSS version 17.0.<br><br>RESULTS: &#xa0;S. aureus was detected in 9.0% (11.4-6.6%, 95% Confidence Interval) of 543 samples, primarily from pus (79.6%, 39/49). Children aged 1 to <3 years most commonly contracted infections (30.6%, 15/49), and males (67.4%, 33/49) had twice as many infections as females (32.7%, 16/49). As high as 84.7% (83/98) of strains were penicillin-resistant, while 18.4% (27/147) were aminoglycoside-resistant. MDR accounted for 79.6% (39/49) of all&#xa0;S. aureus infections, while MRSA and biofilm-formers accounted for 67.6% (33/49) and 24.5% (12/49), respectively. Fluoroquinolone resistance in non-MDR-MRSA-biofilm-formers, MDR-MRSA, MDR-biofilm-formers, and MRSA-biofilm-formers was 31.3%, 46.8%, 58.3%, and 60.0%, respectively, while aminoglycoside resistance was 0%, 32.3%, 50.0%, and 45.0%, and penicillin resistance was 87.5%, 85.5%, 100.0%, and 100.0%.<br><br>CONCLUSIONS: &#xa0;MDR-isolates and MRSA caused nearly four-fifths of S. aureus infections. Compared to MDR and MRSA strains, biofilm-formers triggered higher levels of antimicrobial resistance.}, }
@article {pmid39572562, year = {2024}, author = {Guo, J and Van De Ven, WT and Skirycz, A and Thirumalaikumar, VP and Zeng, L and Zhang, Q and Balcke, GU and Tissier, A and Dehesh, K}, title = {An evolutionarily conserved metabolite inhibits biofilm formation in Escherichia coli K-12.}, journal = {Nature communications}, volume = {15}, number = {1}, pages = {10079}, pmid = {39572562}, issn = {2041-1723}, support = {R01 GM107311/GM/NIGMS NIH HHS/United States ; R01GM107311-8//U.S. Department of Health &amp; Human Services | NIH | National Institute of General Medical Sciences (NIGMS)/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Escherichia coli K12/genetics/metabolism/drug effects/physiology ; *Escherichia coli Proteins/metabolism/genetics ; *Gene Expression Regulation, Bacterial ; *Fimbriae, Bacterial/metabolism/genetics ; Oxidative Stress ; Promoter Regions, Genetic ; Erythritol/analogs &amp; derivatives/metabolism/pharmacology ; }, abstract = {Methylerythritol cyclodiphosphate (MEcPP) is an intermediate in the biosynthesis of isoprenoids in plant plastids and in bacteria, and acts as a stress signal in plants. Here, we show that MEcPP regulates biofilm formation in Escherichia coli K-12 MG1655. Increased MEcPP levels, triggered by genetic manipulation or oxidative stress, inhibit biofilm development and production of fimbriae. Deletion of fimE, encoding a protein known to downregulate production of adhesive fimbriae, restores biofilm formation in cells with elevated MEcPP levels. Limited proteolysis-coupled mass spectrometry (LiP-MS) reveals that MEcPP interacts with the global regulatory protein H-NS, which is known to repress transcription of fimE. MEcPP prevents the binding of H-NS to the fimE promoter. Therefore, our results indicate that MEcPP can regulate biofilm formation by modulating H-NS activity and thus reducing fimbriae production. Further research is needed to test whether MEcPP plays similar regulatory roles in other bacteria.}, }
@article {pmid39572453, year = {2024}, author = {Méndez, A and Sanmartín, P and Balboa, S and Trueba-Santiso, A}, title = {Environmental Proteomics Elucidates Phototrophic Biofilm Responses to Ornamental Lighting on Stone-built Heritage.}, journal = {Microbial ecology}, volume = {87}, number = {1}, pages = {147}, pmid = {39572453}, issn = {1432-184X}, support = {04_IN606D_2021_2598528//Programa de Doutoramento Industrial - Xunta de Galicia/ ; ED431F 2022/14//FONTES project - Xunta de Galicia/ ; ED431F 2022/14//FONTES project - Xunta de Galicia/ ; ED431C 2022/09//Competitive Reference Group (GRC) grant - GEMAP/ ; ED431C 2022/09//Competitive Reference Group (GRC) grant - GEMAP/ ; RYC2020-029987-I//Ram&#xf3;n y Cajal contract - Spanish State Research Agency (AEI)/ ; ED431C-2021/37//Competitive Reference Group (GRC) - Biogroup/ ; ED431C-2021/37//Competitive Reference Group (GRC) - Biogroup/ ; }, mesh = {*Biofilms/radiation effects/growth &amp; development ; *Proteomics ; Light ; Phototrophic Processes ; Cyanobacteria/metabolism/radiation effects/physiology ; Chlorophyta/radiation effects/metabolism/physiology ; Proteome ; Lighting ; }, abstract = {Recent studies are showing that some lights suitable for illuminating the urban fabric (i.e. that do not include the red, green and blue sets of primary colours) may halt biological colonisation on monuments, mainly that caused by phototrophic subaerial biofilms (SABs), which may exacerbate the biodeterioration of substrates. However, the light-triggered mechanisms that cause changes in the growth of the phototrophs remain unknown. Environmental proteomics could be used to provide information about the changes in the SAB metabolism under stress inflicted by nocturnal lighting. Here, laboratory-produced SABs, composed of Chlorophyta, Streptophyta and Cyanobacteriota, were subjected to three types of lighting used for monuments: cool white, warm white and amber + green (potentially with a biostatic effect). A control without light (i.e. darkness) was also included for comparison. The nocturnal lighting impaired the capacity of the SABs to decompose superoxide radicals and thus protect themselves from oxidative stress. Cool white and warm white light both strongly affected the proteomes of the SABs and reduced the total peptide content, with the extent of the reduction depending on the genera of the organisms involved. Analysis of the photo-damaging effect of amber + green light on the biofilm metabolism revealed a negative impact on photosystems I and II and production of photosystem antenna protein-like, as well as a triggering effect on protein metabolism (synthesis, folding and degradation). This research provides, for the first-time, a description of the proteomic changes induced by lighting on SABs colonising illuminated monuments in urban areas.}, }
@article {pmid39572363, year = {2024}, author = {Kim, HT and Çakmak, G and Jo, YH and Jee, EB and Cho, JH and Yoon, HI and Yilmaz, B}, title = {Surface properties and biofilm formation on resins for subtractively and additively manufactured fixed dental prostheses aged in artificial saliva: Effect of material type and surface finishing.}, journal = {The Journal of prosthetic dentistry}, volume = {}, number = {}, pages = {}, doi = {10.1016/j.prosdent.2024.10.039}, pmid = {39572363}, issn = {1097-6841}, abstract = {STATEMENT OF PROBLEM: Additive manufacturing (AM) and subtractive manufacturing (SM) have been widely used for fabricating resin-based fixed dental prostheses. However, studies on the effects of material type (AM or SM resin) and surface finishing (polishing or glazing) on the surface properties and biofilm formation are lacking.<br><br>PURPOSE: The purpose of this in vitro study was to investigate the effects of material type and surface finishing on the surface roughness, wettability, protein adsorption, and microbial adhesion of the AM and SM resins marketed for fixed restorations under artificial saliva-aged conditions.<br><br>MATERIAL AND METHODS: Disk-shaped specimens (&#x2205;10&#xd7;2 mm) were fabricated using 3 types of resins: AM composite resin with fillers (AMC), AM resin without fillers (AMU), and SM composite resin with fillers (SMC). Each resin group was divided into 2 subgroups based on surface finishing: polished (P) and glazed (G). Therefore, 3 polished surface groups (AMCP, AMUP, and SMCP) and 3 glazed surface groups (AMCG, AMUG, and SMCG) were prepared. Specimens were then categorized according to aging condition in artificial saliva. Surface roughness (Ra and Sa), contact angle, surface free energy (SFE), protein adsorption, and microbial adhesion were measured. The data were analyzed using a nonparametric factorial analysis of variances and post hoc tests with Bonferroni correction (&#x3b1;=.05).<br><br>RESULTS: When nonaged, significant interactions between material type and surface finishing were detected for Ra, contact angle, SFE, protein adsorption, and microbial adhesion (P&#x2264;.008). AMCP showed higher Ra and microbial adhesion than AMUP and SMCP, and higher contact angle and protein adsorption than SMCP (P<.001). AMCG had lower SFE than AMUG (P=.005) and higher bacterial adhesion than SMCG (P<.001). AMC had higher Sa than AMU and SMC (P&#x2264;.006). When aged, significant interactions between material type and surface finishing were detected for Ra, Sa, protein adsorption, and microbial adhesion (P&#x2264;.026). The contact angle and SFE were significantly affected only by the material type (P&#x2264;.001), as AMC exhibited higher wettability than SMC (P&#x2264;.004). AMCP had higher Ra and microbial adhesion than AMUP and SMCP (P&#x2264;.003). AMCP had higher Sa and protein adsorption than SMCP (P&#x2264;.004). AMCG showed lower Ra and higher protein adsorption than AMUG (P&#x2264;.001).<br><br>CONCLUSIONS: Both material type and surface finishing significantly affected surface properties and biofilm formation. AMCP exhibited higher surface roughness, protein adsorption, and microbial adhesion compared with SMCP. Glazing may reduce the differences in surface-biofilm interactions between AMC and SMC.}, }
@article {pmid39567638, year = {2024}, author = {Matsumoto, Y and Nakayama, M and Shimizu, Y and Koganesawa, S and Kanai, H and Sugiyama, Y and Kurakado, S and Sugita, T}, title = {Role of Hog1-mediated stress tolerance in biofilm formation by the pathogenic fungus Trichosporon asahii.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {28761}, pmid = {39567638}, issn = {2045-2322}, support = {JP23K06141//Japan Society for the Promotion of Science/ ; JP23fk0108679h0401//Japan Agency for Medical Research and Development/ ; }, mesh = {*Biofilms/growth &amp; development ; *Oxidative Stress ; *Mitogen-Activated Protein Kinases/metabolism/genetics ; Animals ; *Fungal Proteins/genetics/metabolism ; Bombyx/microbiology ; Mutation ; Gene Expression Regulation, Fungal ; Stress, Physiological ; Trichosporon/genetics/physiology ; Basidiomycota ; }, abstract = {Trichosporon asahii, a dimorphic fungus, causes bloodstream infections in immunocompromised patients with neutropenia. Biofilms are formed on the surfaces of medical devices such as catheters as T. asahii transitions morphologically from yeast to hyphae in the host environment. Oxidative stress tolerance and morphological changes of T. asahii are regulated by Hog1, a mitogen-activated protein kinase. The role of Hog1 in the biofilm formation by T. asahii, however, has remained unknown. In the present study, we demonstrated that a hog1 gene-deficient T. asahii mutant formed excess biofilm under a rich medium in vitro, but did not form biofilm in an in vivo evaluation system using silkworms. The hog1 gene-deficient T. asahii mutant formed a greater amount of biofilm than the parent strain in vitro. Under an oxidative stress condition in vitro, however, lower amounts of biofilm were formed by the hog1 gene-deficient T. asahii mutant than by the parent strain. In an in vivo evaluation system using silkworms, lower amounts of biofilm were formed by the hog1 gene-deficient T. asahii mutant than by the parent strain. Our findings suggest that Hog1 regulates biofilm formation by T. asahii in response to host environmental conditions, including oxidative stress.}, }
@article {pmid39566691, year = {2025}, author = {An, X and Chen, S and Fu, J and Yang, C and Xiao, Y and Zhou, Z}, title = {Metabolic coupling of aerobic methane oxidation and short-cut nitrification and denitrification for anaerobic effluent treatment in photo-sequencing batch biofilm reactor.}, journal = {Bioresource technology}, volume = {417}, number = {}, pages = {131845}, doi = {10.1016/j.biortech.2024.131845}, pmid = {39566691}, issn = {1873-2976}, mesh = {*Methane/metabolism ; *Biofilms ; *Nitrification ; *Bioreactors ; *Oxidation-Reduction ; Anaerobiosis ; *Denitrification ; Aerobiosis ; Biofuels ; Ammonia/metabolism ; }, abstract = {This study explored the use of algae to supply oxygen in situ as an alternative to mechanical aeration for anaerobic effluent treatment in a photo-sequencing batch biofilm reactor (PSBBR). By establishing alternating aerobic (dissolved oxygen (DO) > 2 mg /L)/anoxic conditions (<0.5 mg-DO/L) through a 6-h off/6-h on biogas sparging cycle and continuous illumination (1500-3000 lux), the PSBBR achieved a significant ammonia removal rate of 15-25 mg N L[-1]d[-1]. This system demonstrated robust partial nitrification and nitrite reduction activities, coupled with aerobic methane oxidation. Metagenomic analysis revealed the enrichment of key microbial groups, including Leptolyngbyaceae, Methylocystis, Nitrosomonas and Hyphomicrobium. The key functional genes of methane (mmo, mdh, gfa, frm and fdh) and nitrogen (amo, hao, narGHI, and napAB) metabolisms were identified, while notably lacking nitrite oxidation genes. In conclusion, this study provides a promising post-treatment approach for anaerobic effluent through integrating biogas utilization with efficient nitrogen removal.}, }
@article {pmid39566593, year = {2025}, author = {Cui, W and Liang, X and Xiao, W and Wang, Y and Liu, F and Chen, S and Long, J and Jin, Y and Duan, G and Yang, H}, title = {The role and mechanism of efflux pump norB in biofilm formation of Staphylococcus aureus.}, journal = {Gene}, volume = {936}, number = {}, pages = {149105}, doi = {10.1016/j.gene.2024.149105}, pmid = {39566593}, issn = {1879-0038}, mesh = {*Biofilms/growth &amp; development ; *Staphylococcus aureus/genetics ; *Bacterial Proteins/genetics/metabolism ; *Gene Expression Regulation, Bacterial ; Membrane Transport Proteins/genetics/metabolism ; Anti-Bacterial Agents/pharmacology ; Gene Knockout Techniques ; }, abstract = {Staphylococcus aureus (S. aureus) is one of the notorious bacteria responsible for community and hospital infections. It can attach to the indwelling medical devices to form biofilms, which increases resistance to antibiotics and causes frequent chronic or persistent infections. This study attempted to determine the contribution and mechanism between the efflux pump norB gene and biofilm development in S. aureus. The expression levels of norB gene were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The norB gene knockout strain USA300 ΔnorB was constructed by homologous recombination technology. Crystal violet staining was utilized to detect the biofilm formation ability. Differentially expressed genes between norB knockout strains and wild-type strains were screened by RNA-Seq technology and verified by qRT-PCR. In comparison to strains with weak biofilm development capacity, higher expression levels of the norB gene were detected in S. aureus strains that showed strong biofilm forming capabilities. The expression levels of norB were significantly up-regulated in biofilm bacteria in comparison to planktonic bacteria. The knockout of norB gene reduced the biofilm formation ability in S. aureus. The deletion of norB gene up-regulated the expression of genes related to biofilm formation including agrD, sdrC, sdrD, agrB, agrC, fnbB, nuc, lytS, lrgA, sdrE, agrA and saeS, and down-regulated the expression of genes related to biofilm formation including clfA, icaR, sarA and rot. In conclusion, the efflux pump norB gene serves as a crucial role in the production of biofilm, thus rendering it a promising avenue for biofilm suppression.}, }
@article {pmid39566588, year = {2025}, author = {Bamberger, MH}, title = {Editorial Comment on "Indwelling Urological Devise Biofilm Composition and Characteristics in the Presence and Absence of Infection".}, journal = {Urology}, volume = {196}, number = {}, pages = {90}, doi = {10.1016/j.urology.2024.11.016}, pmid = {39566588}, issn = {1527-9995}, }
@article {pmid39566460, year = {2025}, author = {Xia, L and Wang, J and Chen, M and Li, G and Wang, W and An, T}, title = {Biofilm formation mechanisms of mixed antibiotic-resistant bacteria in water: Bacterial interactions and horizontal transfer of antibiotic-resistant plasmids.}, journal = {Journal of hazardous materials}, volume = {481}, number = {}, pages = {136554}, doi = {10.1016/j.jhazmat.2024.136554}, pmid = {39566460}, issn = {1873-3336}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Plasmids/genetics ; *Gene Transfer, Horizontal ; *Escherichia coli/drug effects/genetics ; Anti-Bacterial Agents/pharmacology ; Drug Resistance, Bacterial/genetics ; Water Microbiology ; Bacteria/drug effects/genetics/metabolism ; Microbial Interactions ; }, abstract = {Over 95 % of bacteria on water supply pipeline surfaces exist in biofilms, which are hotspots for antibiotic resistance gene (ARG) transmission. This study established mixed biofilm culture systems on a metal iron substrate using Escherichia coli: antibiotic-sensitive bacteria (ASB) and antibiotic-resistant bacteria (ARB). The growth rate and extracellular polymeric substances (EPS) content of mixed biofilm surpassed single-species biofilms due to synergistic interactions among different bacteria. However, the composition of mixed biofilms formed by ASB and ARB became unstable after 72 h, linked to reduced polysaccharide proportions in EPS and inter-bacterial competition. The bacterial composition and conjugative transfer frequency of ARGs in mixed biofilms indicate that biofilm formation significantly enhances horizontal transfer of ARGs. Notably, the conjugative transfer frequency of the mixed biofilm formed by two ARB increased 100-fold within five days. In contrast, the conjugative transfer frequency in the mixed biofilm formed by ASB and ARB was unstable; inter-bacterial competition led to plasmid loss associated with horizontal transfer of ARGs, ultimately resulting in biofilm shedding. Furthermore, genes associated with ARG transfer and biofilm growth up-regulated by 1.5 - 6 and 2 - 7 times, respectively, in mixed biofilm. These findings highlight a mutually reinforcing relationship between biofilm formation and horizontal ARG transmission, with significant environmental implications.}, }
@article {pmid39566251, year = {2025}, author = {Yao, S and Chen, Y and Zhang, X and Dong, Z}, title = {Enhanced corrosion resistance and biofilm inhibition of TC4 with slight Cu addition against marine Pseudomonas aeruginosa.}, journal = {Bioelectrochemistry (Amsterdam, Netherlands)}, volume = {162}, number = {}, pages = {108852}, doi = {10.1016/j.bioelechem.2024.108852}, pmid = {39566251}, issn = {1878-562X}, mesh = {*Pseudomonas aeruginosa/drug effects/physiology ; Corrosion ; *Copper/pharmacology/chemistry ; *Biofilms/drug effects/growth &amp; development ; *Alloys/chemistry/pharmacology ; *Titanium/chemistry/pharmacology ; Anti-Bacterial Agents/pharmacology/chemistry ; Microbial Sensitivity Tests ; }, abstract = {Ti-6Al-4V (TC4) alloy is widely utilized as the structural material in marine industries owing to its low density, high specific strength, and favorable corrosion resistance. However, as biofouling drastically alters, some reported the major deleterious effect of bacteria has imposed a challenge to improve microbiologically influenced corrosion (MIC) resistance. A further opportunity for solving this problem is Cu micro-alloying, which was inspired by adding Cu for biomedical applications. Herein, a Ti-6Al-4V alloy with slight Cu addition (TC4-Cu) was exposed to 2216E media inoculated with Pseudomonas aeruginosa (P. A.), and then investigated compared to TC4. TC4-Cu exhibits lower corrosion current, more denser passive film, and lower weight loss with weaker pitting (a maximum pitting depth of 0.2 μm), compared to TC4 with a maximum pitting crater depth of 9.6 μm. Those demonstrated that the presence of Cu significantly improved the MIC resistance, and inhibited the proliferation of P. A., leading to a good antimicrobial efficacy against marine P. A. Moreover, besides the well-known bactericidal role, Cu ions were transferred to form Cu2O and CuO, constituting protective corrosion products, and thus improving the anti-microbial properties of TC4-Cu.}, }
@article {pmid39562179, year = {2025}, author = {Xu, L and Lu, B and Xie, K and Fan, W and Fang, S and Zhu, J and Yang, J and Xu, B}, title = {Photothermal Nano-Immunotherapy Against Methicillin-Resistant Staphylococcus aureus (MRSA) Biofilm Infections.}, journal = {Advanced healthcare materials}, volume = {14}, number = {3}, pages = {e2403318}, doi = {10.1002/adhm.202403318}, pmid = {39562179}, issn = {2192-2659}, support = {2022CCZC02//Traditional Chinese Medicine Inheritance Innovation Research project in Anhui Province/ ; 2022AH051251//Anhui Provincial Scientific Research Compilation Project/ ; 2022AH010076//Anhui Provincial Scientific Research Compilation Project/ ; 2023AH053407//Anhui Provincial Scientific Research Compilation Project/ ; 2408085MH197//Natural Science Foundation project of Anhui Province/ ; }, mesh = {*Methicillin-Resistant Staphylococcus aureus/drug effects/physiology ; Animals ; *Biofilms/drug effects ; Mice ; *Staphylococcal Infections/drug therapy/therapy ; *Immunotherapy/methods ; Photothermal Therapy/methods ; Metformin/pharmacology/chemistry ; Anti-Bacterial Agents/pharmacology/chemistry ; Humans ; Phototherapy/methods ; Mice, Inbred BALB C ; Titanium/chemistry/pharmacology ; }, abstract = {Methicillin-resistant Staphylococcus aureus (MRSA) biofilm infections are a prevalent type of biofilm-associated infection with a poor prognosis and antibiotic resistance. The senescence of immune cells in the immune microenvironment contributes to biofilm formation. In this study, Ti3C2 MXene-PVA nanosheets loaded with metformin (Met@TiC) are developed for the treatment of MRSA biofilm infections. Nanosheets utilize near-infrared light to induce photothermal effects and provide direct bactericidal activity against biofilm structures. Met, which is known for its anti-inflammatory and anti-senescence properties, modulates immune responses by revitalizing the function of senescent macrophages within the biofilm microenvironment, thereby enhancing their phagocytic and biofilm-eradicating capabilities. The efficacy of this nanoplatform both in vitro and in an MRSA biofilm infection mouse model, demonstrating its potential as a photothermal nanoimmunotherapy for combating MRSA biofilm infections is validated. In summary, the Met@TiC nanoplatform offers a significant alternative to clinical solutions for MRSA biofilm infections.}, }
@article {pmid39562098, year = {2025}, author = {Tian, X and Hu, H and Fan, L and Yang, J and Zhao, H and Zhang, L and Hu, D and Hao, G and Du, F and Wang, P}, title = {Smart β-cyclodextrin-dominated helical supramolecular dendritic assemblies improve the foliar affinity and biofilm disruption for treating alarming bacterial diseases.}, journal = {Carbohydrate polymers}, volume = {348}, number = {Pt A}, pages = {122823}, doi = {10.1016/j.carbpol.2024.122823}, pmid = {39562098}, issn = {1879-1344}, mesh = {*Biofilms/drug effects ; *beta-Cyclodextrins/chemistry/pharmacology ; *Anti-Bacterial Agents/pharmacology/chemistry ; Dendrimers/chemistry/pharmacology ; Plant Leaves/chemistry ; Animals ; }, abstract = {Recent outbreaks of alarming bacterial diseases have significantly impacted global agricultural productivity. Conventional bactericides exhibit certain limitations in efficiently impeding biofilm formation and annihilating biofilm-dispersed pathogens, and often expose to high off-target movement during foliar spraying. Here, we produce an innovative helical dendrimer-like supramolecular material (PhA28@β-CD) assembled by a bioactive small-molecule 2-chlorophenylisopropanolamine (PhA28) and β-cyclodextrin (β-CD) through host-guest recognition principle. In this system, the advisable optimization by a macrocyclic oligosaccharide-β-CD significantly enhances the water-solubility, biocompatibility, and bioavailability of PhA28. At a low-dose of 6.8 μg/mL, PhA28@β-CD discloses an outstanding biofilm disruption rate of 82.4 %, notably exceeding that of PhA28 (60.6 %), which thereby reduces the biofilm-associated virulence. Meanwhile, the self-assembled PhA28@β-CD possesses superior wetting and dispersing properties on hydrophobic leaves, leading to effective foliar deposition and prolong retention of active components. In vivo studies reveal that PhA28@β-CD exhibits superior curative (66.0 %) and protective (72.6 %) activities against citrus canker at 200 μg/mL, markedly surpassing those of the existing bactericide thiodiazole‑copper (46.8 % and 52.2 %) and single PhA28. This material also has broad-spectrum control efficiency (53.0 % ~ 59.5 %) against rice bacterial blight. This research lays the groundwork for developing carbohydrate-optimized multifunctional dendrimer-like assemblies aimed at disrupting biofilms and improving sustained bioavailability to combat bacterial diseases.}, }
@article {pmid39561505, year = {2025}, author = {Bellavita, R and Casciaro, B and Nocerino, V and Palladino, S and Loffredo, MR and Dardano, P and De Stefano, L and Falcigno, L and D'Auria, G and Galdiero, S and Falanga, A}, title = {Myxinidin-analogs able to sequester Fe(III): Metal-based gun to combat Pseudomonas aeruginosa biofilm.}, journal = {Journal of inorganic biochemistry}, volume = {263}, number = {}, pages = {112774}, doi = {10.1016/j.jinorgbio.2024.112774}, pmid = {39561505}, issn = {1873-3344}, mesh = {*Pseudomonas aeruginosa/drug effects ; *Biofilms/drug effects/growth &amp; development ; *Ferric Compounds/chemistry/pharmacology ; *Anti-Bacterial Agents/pharmacology/chemistry ; Iron/chemistry ; Antimicrobial Peptides/chemistry/pharmacology ; Microbial Sensitivity Tests ; }, abstract = {Bacteria have developed a tendency to form biofilms, where bacteria live in organized structures embedded in a self-produced matrix of DNA, proteins, and polysaccharides. Additionally, bacteria need iron(III) as an essential nutrient for bacterial growth and secrete siderophore groups that sequester it from the environment. To design a molecule able both to inhibit the bacteria and to sequester iron, we developed two hydroxamate-based peptides derived from an analog (WMR-4), previously developed in our lab, of the antimicrobial peptide myxinidin. In detail, we proposed a combination of WMR-4 with the hydroxamic acid resulting in the peptides WMR-7 and WMR-16 which differ for the length of the linker between the antimicrobial moiety and the siderophore. Both peptides were characterized through a set of different biophysical experiments to investigate their ability to sequester Fe[3+]. The peptide‑iron(III) complexes were studied through the UV-visible spectroscopy in organic solvent to eliminate water competition, and in acidic water to avoid iron precipitation. The complexes were also characterized by performing electrochemistry, circular dichroism and NMR spectroscopy experiments. In addition, we demonstrated the ability of peptide‑iron(III) complexes to inhibit the biofilm of Pseudomonas aeruginosa and to have an impact on the cell motility. This metal-based approach consisting in a hydroxamic acid conjugation represents a promising strategy to enhance the antibiofilm activity of antimicrobial peptides against one of most dangerous bacteria such as Pseudomonas aeruginosa.}, }
@article {pmid39561392, year = {2025}, author = {Basnet, A and Chand, AB and Bajracharya, S and Shrestha, MR and Shrestha, S and Tamang, B and Dulal, M and Pokhrel, N and Shrestha, LB}, title = {Biofilm Formation and Plasmid-Mediated Quinolone Resistance Genes at Varying Quinolone Inhibitory Concentrations in Quinolone-Resistant Bacteria Superinfecting COVID-19 Inpatients.}, journal = {The American journal of tropical medicine and hygiene}, volume = {112}, number = {2}, pages = {346-354}, pmid = {39561392}, issn = {1476-1645}, mesh = {*Biofilms/drug effects/growth &amp; development ; Humans ; *Quinolones/pharmacology ; *Plasmids/genetics ; *Anti-Bacterial Agents/pharmacology ; *COVID-19 ; *Microbial Sensitivity Tests ; Cross-Sectional Studies ; *Drug Resistance, Bacterial/genetics ; *SARS-CoV-2/genetics/drug effects ; Gram-Negative Bacteria/drug effects/genetics ; Inpatients ; }, abstract = {The likelihood of antimicrobial failure in COVID-19 patients with bacterial superinfection arises from both phenotypic (biofilms) and genotypic mechanisms. This cross-sectional study aimed to determine the inhibitory concentrations of quinolones-nalidixic acid, norfloxacin, ciprofloxacin, ofloxacin, and levofloxacin-in biofilm formers (minimum biofilm inhibitory concentration [MBIC]) and nonformers (minimum inhibitory concentration [MIC]) and correlate inhibitory concentrations with plasmid-mediated quinolone resistance (PMQR) genes in quinolone-resistant bacteria isolated from COVID-19 inpatients. Quinolone-resistant bacteria (n = 193), verified through disc diffusion, were tested for quinolone inhibitory concentrations using broth microdilution and biofilm formation using microtiter plate methods. The polymerase chain reaction was used to detect PMQR genes. Study variables were analyzed using SPSS v.17.0, with a significance level set at P <0.05. MIC-to-MBIC median fold increases for ciprofloxacin, ofloxacin, and levofloxacin were 128 (2-8,192), 64 (4-1,024), and 32 (4-512) in gram-positive cocci (GPC, n = 43), respectively, whereas they were 32 (4-8,192), 32 (4-2,048), and 16 (2-1,024) in fermentative gram-negative bacilli (F-GNB, n = 126) and 16 (4-4,096), 64 (2-64), and 16 (8-512) in nonfermentative gram-negative bacilli (NF-GNB, n = 24). In biofilm-forming F-GNB and NF-GNB, qnrB (10/32 versus 3/10), aac(6')-Ib-cr (10/32 versus 4/10), and qnrS (9/32 versus 0/10) genes were detected. A 32-fold median increase in the MIC-to-MBIC of ciprofloxacin was significantly (P <0.05) associated with qnrA in F-GNB and qnrS in NF-GNB. Biofilms formed by F-GNB and NF-GNB were significantly associated with the aac(6')-Ib-cr and qnrS genes, respectively. Nearly one-third of the superinfecting bacteria in COVID-19 patients formed biofilms and had at least one PMQR gene, thus increasing the need for quinolones at higher inhibitory concentrations.}, }
@article {pmid39559081, year = {2024}, author = {Calo', L and Rodolico, D and Galli, J}, title = {Direct Biofilm Visualization in Voice Prosthesis.}, journal = {Indian journal of otolaryngology and head and neck surgery : official publication of the Association of Otolaryngologists of India}, volume = {76}, number = {6}, pages = {6090-6091}, pmid = {39559081}, issn = {2231-3796}, }
@article {pmid39557280, year = {2025}, author = {Reis, FN and Câmara, JVF and Abuna, G and Moraes, SM and da Silva, NDG and Ventura, TMO and Araujo, TT and Rodrigues, CMVBF and Pardi, V and Murata, RM and Buzalaf, MAR}, title = {Resveratrol alters oral biofilm in vitro and in vivo.}, journal = {Journal of dentistry}, volume = {152}, number = {}, pages = {105466}, doi = {10.1016/j.jdent.2024.105466}, pmid = {39557280}, issn = {1879-176X}, mesh = {Adult ; Animals ; Cattle ; Female ; Humans ; Male ; Young Adult ; Antioxidants/pharmacology ; *Biofilms/drug effects ; Cariostatic Agents/pharmacology ; *Chlorhexidine/pharmacology ; Cross-Over Studies ; *Dental Caries/microbiology/prevention &amp; control ; *Dental Enamel/drug effects/microbiology ; Double-Blind Method ; Microradiography ; *Resveratrol/pharmacology ; *Saliva/microbiology ; Sodium Fluoride/pharmacology ; *Streptococcus mutans/drug effects ; Sucrose/pharmacology ; Tooth Demineralization/prevention &amp; control/microbiology ; }, abstract = {OBJECTIVE: To evaluate the ability of resveratrol to reduce dental caries in vitro and in vivo.<br><br>METHODS: In part 1, a microcosm biofilm protocol was employed. One hundred twenty-six bovine enamel specimens were treated with: Resveratrol (50, 100, 200, 400 &#xb5;g/mL), Phosphate buffered saline (negative control), Dimethyl sulfoxide (negative control) and 0.12% Chlorhexidine (positive control). The biofilm was produced from the saliva of 10 volunteers, under 0.2% sucrose exposure for 5 days, and daily treated with the solutions (1 min). At the end of the experimental period, resazurin and viable plate count assays were performed. Enamel demineralization was evaluated by transverse microrradiography (TMR). In part 2, 12 volunteers participated in a triple-blind crossover protocol for 7 weeks, according to the following treatments: 1) 100 mg/L resveratrol; 2) 0.05% NaF (226 mg/L F); 3) 100 mg/L resveratrol + 0.05% NaF; 4) Deionized water (negative control). Biofilm samples were collected from both sides of the mouth 12 h after the use of the solutions.<br><br>RESULTS: Resveratrol at 50 and 200 &#xb5;g/mL significantly reduced biofilm metabolic activity and mutans streptococci, respectively. Chlorhexidine was an effective treatment to significantly reduce all parameters, being an important antimicrobial and anticaries agent in vitro. Resveratrol alone or associated with NaF modulated several caries-associated bacteria in vivo.<br><br>CONCLUSION: The present study represents the first step regarding the use of resveratrol within the concept of acquired enamel pellicle and biofilm engineering to prevent dental caries.}, }
@article {pmid39557100, year = {2025}, author = {Fan, XY and Zhou, SL and Yang, Y and Cao, SB and Niu, Y and Zheng, MY and Zhao, JR}, title = {Impact of carbon/nitrogen ratio on sequencing batch biofilm reactors initiated with different seed sludges for treating actual mariculture effluents.}, journal = {Bioresource technology}, volume = {417}, number = {}, pages = {131838}, doi = {10.1016/j.biortech.2024.131838}, pmid = {39557100}, issn = {1873-2976}, mesh = {*Nitrogen ; *Biofilms ; *Carbon/pharmacology ; *Bioreactors ; *Sewage/microbiology ; Bacteria/metabolism ; Archaea/metabolism/genetics ; Nitrification ; Waste Disposal, Fluid/methods ; Water Purification/methods ; Denitrification ; }, abstract = {The impact of carbon/nitrogen (C/N) ratio on sequencing batch biofilm reactor (SBBR) initiated with different seed sludges for treating actual mariculture effluent was explored. Increasing the C/N ratio significantly enhanced the nitrogen removal efficiency, achieving average removal efficiency of 95% for ammonia nitrogen and 73% for total nitrogen at ratio of 30, while the impact of seed sludge was minimal. High C/N ratio promoted the secretion of tightly bound extracellular polymeric substances (TB-EPS), which showed significant correlation with nitrogen removal. Interactions between bacteria and archaea were enhanced and conditionally rare or abundant taxa were the keystone taxa. High C/N ratio inhibited the relative abundance of ammonia-oxidizing archaea (Candidatus_Nitrosopumilus) and bacteria (Nitrosomonas), but promoted the heterotrophic nitrification-aerobic denitrification bacteria (Halomonas). The expression of nitrogen removal functional genes significantly correlated with functional genera. This study emphasized the crucial role of high C/N ratios in biological nitrogen removal from actual mariculture effluent.}, }
@article {pmid39556104, year = {2024}, author = {You, Z and Yu, H and Zhang, B and Liu, Q and Xiong, B and Li, C and Qiao, C and Dai, L and Li, J and Li, W and Xin, G and Liu, Z and Li, F and Song, H}, title = {Engineering Exopolysaccharide Biosynthesis of Shewanella oneidensis to Promote Electroactive Biofilm Formation for Liquor Wastewater Treatment.}, journal = {ACS synthetic biology}, volume = {}, number = {}, pages = {}, doi = {10.1021/acssynbio.4c00417}, pmid = {39556104}, issn = {2161-5063}, abstract = {Microbial electrochemical systems (MESs), as a green and sustainable technology, can decompose organics in wastewater to recover bioelectricity. Electroactive biofilms, a microbial community structure encased in a self-produced matrix, play a decisive role in determining the efficiency of MESs. However, as an essential component of the biofilm matrix, the role of exopolysaccharides in electroactive biofilm formation and their influence on extracellular electron transfer (EET) have been rarely studied. Herein, to explore the effects of exopolysaccharides on biofilm formation and EET rate, we first inhibited the key genes responsible for exopolysaccharide biosynthesis (namely, so_3171, so_3172, so_3177, and so_3178) by using antisense RNA in Shewanella oneidensis MR-1. Then, to explore the underlying mechanisms why inhibition of exopolysaccharide synthesis could enhance biofilm formation and promote the EET rate, we characterized cell physiology and electrophysiology. The results showed inhibition of exopolysaccharide biosynthesis not only altered cell surface hydrophobicity and promoted intercellular adhesion and aggregation, but also increased biosynthesis of c-type cytochromes and decreased interfacial resistance, thus promoting electroactive biofilm formation and improving the EET rate of S. oneidensis. Lastly, to evaluate and intensify the capability of exopolysaccharide-reduced strains in harvesting electrical energy from actual liquor wastewater, engineered strain Δ3171-as3177 was further constructed to treat an actual thin stillage. The results showed that the output power density reached 380.98 mW m[-2], 11.1-fold higher than that of WT strain, which exhibited excellent capability of harvesting electricity from actual liquor wastewater. This study sheds light on the underlying mechanism of how inhibition of exopolysaccharides impacts electroactive biofilm formation and EET rate, which suggested that regulating exopolysaccharide biosynthesis is a promising avenue for increasing the EET rate.}, }
@article {pmid39555918, year = {2024}, author = {Brandt, P and Singha, R and Ene, IV}, title = {Hidden allies: how extracellular vesicles drive biofilm formation, stress adaptation, and host-immune interactions in human fungal pathogens.}, journal = {mBio}, volume = {15}, number = {12}, pages = {e0304523}, pmid = {39555918}, issn = {2150-7511}, support = {RESISTEV//Agence Nationale de la Recherche (ANR)/ ; //CIFAR/ ; PTR MECHETE//Institut Pasteur/ ; }, mesh = {*Extracellular Vesicles/immunology/metabolism ; Humans ; *Biofilms/growth &amp; development ; *Host-Pathogen Interactions/immunology ; *Fungi/immunology/physiology/pathogenicity ; Mycoses/immunology/microbiology ; Stress, Physiological ; Adaptation, Physiological ; }, abstract = {Pathogenic fungi pose a significant threat to human health, especially given the rising incidence of invasive fungal infections and the emergence of drug-resistant strains. This requires the development of vaccines and the advancement of antifungal strategies. Recent studies have focused on the roles of fungal extracellular vesicles (EVs) in intercellular communication and host-pathogen interactions. EVs are nanosized, lipid membrane-bound particles that facilitate the transfer of proteins, lipids, and nucleic acids. Here, we review the multifaceted functions of EVs produced by different human fungal pathogens, highlighting their importance in the response of fungal cells to different environmental cues and their interactions with host immune cells. We summarize the current state of research on EVs and how leveraging this knowledge can lead to innovative approaches in vaccine development and antifungal treatment.}, }
@article {pmid39555709, year = {2024}, author = {Sales, LS and de Farias, AL and Meneguin, AB and Barud, HDS and Brighenti, FL}, title = {Carvacrol incorporation into novel controlled-release mucoadhesive systems for oral polymicrobial biofilm control.}, journal = {Biofouling}, volume = {40}, number = {10}, pages = {893-903}, doi = {10.1080/08927014.2024.2426759}, pmid = {39555709}, issn = {1029-2454}, mesh = {*Cymenes/pharmacology/chemistry ; *Biofilms/drug effects ; *Delayed-Action Preparations ; Alginates/chemistry ; Polysaccharides, Bacterial/chemistry ; Microbial Viability/drug effects ; Anti-Bacterial Agents/pharmacology/administration &amp; dosage/chemistry ; }, abstract = {The aim of this study was to evaluate carvacrol antimicrobial activity in polymicrobial biofilms using a novel controlled-release mucoadhesive systems developed from biopolymers. The natural polymers gellan gum and sodium alginate were used in different concentrations for the development of films, tablets and microparticles containing carvacrol. The systems were characterized as regard their morphological characteristics, carvacrol release and mucoadhesion. Furthermore, the antimicrobial activity of the systems was evaluated on polymicrobial biofilms through biomass quantification and microbial viability assessment. Carvacrol release profile from films, tablets and microparticles was similar; nearly 100% of the carvacrol was released within 15 min. Films showed the best mucoadhesion values. Scanning Electron Microscopy images showed that the films presented a continuous and smooth surface, and the tablets showed a continuous surface with a polymer web appearance. The microparticles were spherical in shape. The films containing carvacrol showed the highest biomass and microbial viability reduction, followed by the tablets. The findings of this study showed that carvacrol incorporated into films and tablets presented antimicrobial activity on polymicrobial biofilm. Controlled-release mucoadhesive systems is a process little explored in dentistry, being the differential of this work, and with great innovative potential for the management of dental diseases.}, }
@article {pmid39555139, year = {2024}, author = {Cho, JA and Jeon, S and Kwon, Y and Roh, YJ and Shin, S and Lee, CH and Kim, SJ}, title = {Identification and comparison of protein composition of biofilms in response to EGCG from Enterococcus faecalis and Staphylococcus lugdunensis, which showed opposite patterns in biofilm-forming abilities.}, journal = {Biofilm}, volume = {8}, number = {}, pages = {100232}, pmid = {39555139}, issn = {2590-2075}, abstract = {Bacterial biofilm is resistant to conventional antibiotic treatments, leading to complications associated with many infection-related human diseases. Epigallocatechin Gallate (EGCG), a phenolic catechin enriched in green tea, is recognized for its anti-bacterial and anti-biofilm activities. In this study, we examined the protein components of the biofilms formed in the absence or presence of EGCG using Enterococcus faecalis and Staphylococcus lugdunensis, which had shown opposing patterns in biofilm formation. A clustering heatmap revealed that the two microorganisms expressed the different protein sets in response to EGCG. Proteins that were noticeably upregulated included those associated with stress responsiveness and gluconeogenesis in E. faecalis, and gene modification in S. lugdunensis. Conversely, downregulated proteins were related to tRNA-modifying enzyme activity in E. faecalis, and anabolic metabolism in S. lugdunensis. Among the proteins identified only in EGCG-responsive biofilms, enzymes involved in de novo purine biosynthesis were enriched in E. faecalis, while proteins likely to cause DNA instability and pathogenicity changes were abundantly present in S. lugdunensis. The classification based on gene ontology (GO) terms by microorganism exhibited that metabolic process or catabolic activity was at the top rank in E. faecalis with more than 33 proteins, and in S. lugdunensis, localization or transport was highly ranked with 4 proteins. These results support the hypothesis that EGCG might cause different cellular programs in each microorganism. Finally, comparison of the proteomes between two groups that form biofilms to similar extents discovered that 2 proteins were commonly found in the weak biofilm-forming groups (E. faecalis and EGCG-responding S. lugudunensis), whereas 9 proteins were common among the strong biofilm-forming groups (S. lugdunensis and EGCG-responding E. faecalis). It was suggested that these proteins could serve as potential indicators to detect the presence and predict the extent of biofilm formation by multiple microorganisms. Taken all together, proteomics data and analyses performed in this study provided useful and new information on the proteins embedded in the biofilms formed at the specific conditions, which can aid in diagnosis and the development of tailored treatment strategies.}, }
@article {pmid39555138, year = {2024}, author = {Sunnerhagen, T and Bjarnsholt, T and Qvortrup, K and Bundgaard, H and Moser, C}, title = {Transcatheter aortic valve implantation (TAVI) prostheses in vitro - biofilm formation and antibiotic effects.}, journal = {Biofilm}, volume = {8}, number = {}, pages = {100236}, pmid = {39555138}, issn = {2590-2075}, abstract = {BACKGROUND: Transcatheter aortic valve implantation (TAVI) is a percutaneous catheter-based treatment of aortic stenosis as an alternative to open heart valve surgery. In cases of TAVI endocarditis, the treatment possibilities may be limited as surgical removal of the infected valve may be associated with a high risk in elderly, comorbid or frail patients. The propensity of bacteria to form a biofilm on foreign material is assumed to be of importance part of the disease process in TAVI endocarditis, but no studies on biofilm formation on TAVI valves have been conducted. We hypothesize that Staphylococcus aureus and Enterococcus faecalis biofilm formation on TAVI valves may have an impact on antibiotic tolerance and non-surgical cure rates.<br><br>METHODS: TAVI valves (pieces including part of the metal frame, approximately 1&#xa0;cm wide) were exposed to either species in vitro in LB-Krebs Ringer medium at 37&#xa0;&#xb0;C, with the bacterial count being assessed by culturing of sonicated TAVI pieces and broth at 0, 4, 18 and 24&#xa0;h after bacterial exposure. Scanning electron microscopy (SEM) was performed. Effects of ampicillin, gentamicin, moxifloxacin, rifampicin (for S. aureus), and ceftriaxone (for E. faecalis) at 5 times minimal inhibitory concentration were tested alone and in combination with ampicillin. Antibiotics were added to biofilm aged 0 or 24&#xa0;h and the effects assessed.<br><br>RESULTS: Exposure for 15&#xa0;min established attachment to all of valve pieces. SEM findings were consistent with biofilm formation and suggested lower amounts of bacteria on the metal compared to the tissue part of the TAVI valves. The number of bacteria attached to the TAVI valves increased until 24&#xa0;h of incubation from less than 10^1 to a level of approximately 10^9&#xa0;CFU/g. The bacteria became more tolerant to antibiotics on the TAVI valves over time, with the bactericidal effect against 24-h old biofilm being significantly less effective than against 0-h old biofilm depending on antibiotic.<br><br>CONCLUSIONS: The results indicate that bacteria can adhere to metal and tissue parts of the TAVI valves within minutes after an exposure which is comparable to transient bacteremia in vivo, and that the bacteria rapidly gain biofilm properties, associated with significantly reduced antibiotic effect.}, }
@article {pmid39555077, year = {2024}, author = {Sempere, J and Yuste, J and Domenech, M}, title = {PCV13 vaccine prevents pneumococcal biofilms without affecting Staphylococcus aureus population within the polymicrobial biofilm.}, journal = {Frontiers in immunology}, volume = {15}, number = {}, pages = {1495932}, pmid = {39555077}, issn = {1664-3224}, mesh = {*Biofilms/growth &amp; development ; Humans ; *Pneumococcal Vaccines/immunology ; *Streptococcus pneumoniae/immunology ; *Staphylococcus aureus/immunology/physiology ; *Pneumococcal Infections/prevention &amp; control/immunology/microbiology ; Staphylococcal Infections/prevention &amp; control/immunology/microbiology ; Adult ; Female ; Male ; Middle Aged ; Vaccines, Conjugate/immunology ; }, abstract = {In respiratory pathogens such as Streptococcus pneumoniae, biofilm formation is associated with the colonization of the nasopharynx and chronic respiratory infection. Previous data have shown that pneumococcal conjugate vaccines (PCVs) had an impact on S. pneumoniae colonization and a potential replacement by other respiratory pathogens such as Staphylococcus aureus. The objective of this work was to evaluate the evasion of the immune system by monospecific biofilms and by S. aureus-S. pneumoniae mixed biofilms. We performed opsonophagocytosis assays (OPA) using human HL-60 against previously disaggregated monospecific biofilms of MSSA, MRSA and S. aureus-S. pneumoniae mixed biofilms. We used pre-immune and post-immune serum from immunocompetent adult patients vaccinated with PCV13. Immune sera had a clear effect in reducing pneumococcal biofilms of serotypes 3, 14, 18C, 19F and 19A, whereas had no effect in non-PCV13 serotypes such as 8, 11A and 24F. Our study confirmed that serum from vaccinated patients with PCV13 did not have any effect in reducing S. aureus population in monospecific biofilms, regardless the methicillin resistance phenotype. Moreover, immunized sera from vaccinated patients with PCV13 did not have any effect in S. aureus population in the mixed biofilm, whereas significantly reduced the population of pneumococcal serotype 19A strain in the mixed biofilm which is of great interest because this serotype is included in PCV13, and it is associated with vaccine failures.}, }
@article {pmid39555046, year = {2024}, author = {Wei, T and Ran, T and Rong, W and Zhou, Y}, title = {Efficient and sustainable removal of linear alkylbenzene sulfonate in a membrane biofilm: Oxygen supply dosage impacts mineralization pathway.}, journal = {Water research X}, volume = {25}, number = {}, pages = {100268}, pmid = {39555046}, issn = {2589-9147}, abstract = {Linear alkylbenzene sulfonate (LAS) can be thoroughly mineralized within sufficient oxygen (O2), but which is energy intensive and may causes serious foaming problem. Although cometabolism can achieve efficient LAS removal within a wide range of O2 dosages, how O2 dosage systematically affects LAS metabolic pathway is still unclear. Here, membrane aerated biofilm reactor (MABR) enabled accurate O2 delivery and bulk dissolved oxygen (DO) control. MABR achieved efficient removal of LAS (>96.4 %), nitrate (>97.8 %) and total nitrogen (>96.2 %) at the three target DO conditions. At high DO condition (0.6 mg/L), LAS was efficiently removed by aerobic mineralization (predominant) coupled with aerobic denitrification biodegradation with the related functional enzymes. Pseudomonas, Flavobacterium, Hydrogenophaga, and Pseudoxanthomonas were dominant genus contributing to four possible LAS aerobic metabolic pathways. As O2 dosage reduced to only 29.7 % of the demand for LAS mineralization, O2 facilitated LAS activation, benzene-ring cleavage and a portion of respiration. NO3 [-]-N respiration-induced anaerobic denitrification also contributed to ring-opening and organics mineralization. Desulfomicrobium and Desulfonema related two possible anaerobic metabolic pathways also contributed to LAS removal. The findings provide a promising strategy for achieving low-cost high LAS-containing greywater treatment.}, }
@article {pmid39554441, year = {2024}, author = {Pal, S and Villani, S and Mansi, A and Marcelloni, AM and Chiominto, A and Amori, I and Proietto, AR and Calcagnile, M and Alifano, P and Bagheri, S and Mele, C and Licciulli, A and Sannino, A and Demitri, C}, title = {Antimicrobial and Superhydrophobic CuONPs/TiO2 Hybrid Coating on Polypropylene Substrates against Biofilm Formation.}, journal = {ACS omega}, volume = {9}, number = {45}, pages = {45376-45385}, pmid = {39554441}, issn = {2470-1343}, abstract = {Biofilm formation in common public places and hospitals is of great concern. Active antimicrobial coatings can prevent the formation of bacterial biofilms and the spreading of primary and secondary infections caused by contagious bacteria and viruses. In the present work, we report a simple spray coating process using copper oxide (CuO) nanoparticles (NPs) dispersed in a titanium dioxide (TiO2) sol, where CuONPs act as the active antimicrobial agent and TiO2 as the inorganic binder. Homogeneous CuONPs/TiO2 coating was obtained on polypropylene substrates by spraying the CuO/TiO2 sol using a commercial air gun, followed by drying at 80 °C. The amount of CuONPs loading in the coating was adjusted by controlling the number of coated layers. CuONPs and CuONPs/TiO2 coatings were characterized by XRD, BET, X-ray fluorescence spectroscopy, AFM, and field emission scanning electron microscopy techniques. All of the coated films showed dual activity, i.e., antimicrobial and superhydrophobicity. A high bactericidal effect against both Escherichia coli and Staphylococcus aureus was observed for the coated substrates. Coatings with higher CuONPs showed greater antibacterial activity, reaching R value >6, and no bacterial colonies were detected after 24 h of incubation. An increasing trend of water contact angle was observed with the increasing amount of CuONP loading.}, }
@article {pmid39553752, year = {2024}, author = {Al-Taii, NA and Al-Gburi, NM and Khalil, NK}, title = {Detection of biofilm formation and antibiotics resistance of Staphylococcus spp. isolated from humans' and birds' oral cavities.}, journal = {Open veterinary journal}, volume = {14}, number = {9}, pages = {2215-2223}, pmid = {39553752}, issn = {2218-6050}, mesh = {Animals ; *Staphylococcus/drug effects/isolation &amp; purification/physiology ; *Biofilms/drug effects ; Humans ; *Mouth/microbiology ; *Anti-Bacterial Agents/pharmacology ; *Staphylococcal Infections/veterinary/microbiology ; Birds/microbiology ; Drug Resistance, Bacterial ; Microbial Sensitivity Tests/veterinary ; Prevalence ; Bird Diseases/microbiology ; }, abstract = {BACKGROUND: Staphylococcus spp. are widely distributed in nature and can cause nosocomial, skin infections, and foodborne illness, and it may lead to severe financial losses in birds by causing systemic infection in numerous organs.<br><br>AIM: This study was conducted to determine the prevalence of Staphylococcus spp. in humans and birds in Baghdad city.<br><br>METHODS: Seventy-six oral cavity swabs were collected, including 41 from birds and 35 from breeders. All samples were examined by bacteriological methods and identified by using the VITEK technique, the samples were then further studied to test the ability of biofilm formation, and multidrug-resistant (MDR) factors and MAR index were tested with the use of seven antibiotics.<br><br>RESULTS: Among the 76 oral swabs, 37 samples were positive (48.68%) for Staphylococcus spp.: 7 human samples (20%) and 30 bird samples (73.17%). In humans, Staphylococcus lentus was the most prevalent (42.85%) followed by Staphylococcus aureus (28.57%), Staphylococcus hominis and Staphylococcus sciuri were at (14.29%) to each. In birds, Staphylococcus pseudintermedius, Staphylococcus gallinarum, S. lentus, Staphylococcus haemolyticus, Staphylococcus spp, S. sciuri, and Staphylococcus xylosus were detected in 36.67%, 16.67%, 10%, 10%, 13.33%, 3.33% and 3.33%, respectively. Staphylococcus isolates from the human samples demonstrated that only S. lentus was resistant 33.33% to ME, OX, and SXT. Furthermore, one of them was MDR and high MAR index value. The antimicrobial pattern of Staphylococcus spp. isolated from birds was as follows S. pseudintermedius isolates demonstrated 100% resistance to CN, CIP, SXT, and MDR (100%) and high MAR indices value; S. xylosus was resistant 100% against ME, CN, SXT, and Do and it was MDR with high MAR index; S. lentus was resistant 25% against ME, OX, C, and SXT, whereas, S. gallinarum was resistant 33.33% against ME and OX. The results demonstrated that biofilm formation of the Staphylococcus spp. isolated from human samples were weak biofilm formers: S. lentus, S. hominis, and S. aureus, while other S. aureus (50%) was moderate. In birds, the majority of the isolates had non-biofilm-producing capabilities, while 80% of S. lentus and 100% of S. xylosus showed moderate biofilm formation.<br><br>CONCLUSION: Healthcare problem was observed in this study due to high MDR and MAR index among Staphylococcus spp. isolated from pet birds to their owners and vice versa.}, }
@article {pmid39553305, year = {2024}, author = {Umar, K and Abdullahi, IN and Magashi, AM and Kawo, AH and Usman, Y and El-Fulaty Ahmad, A and Torres, C}, title = {Prevalence and clonal lineages of biofilm-producing Staphylococcus aureus from clinical samples and healthcare workers at Ahmadu Bello University Teaching Hospital, Nigeria.}, journal = {GMS hygiene and infection control}, volume = {19}, number = {}, pages = {Doc49}, pmid = {39553305}, issn = {2196-5226}, abstract = {This study determined the frequency and molecular features of Staph y lo coccus aureus from 206 burn and wound patients (BWPs) as well as 94 healthcare workers (HCWs) at the Ahmadu Bello University Teaching Hospital, Zaria, Northern Nigeria. Nine (4.4%) and five (5.3%) samples from BWPs and HCWs were identified as S. aureus positive, respectively. Seven (50%) were mecA-positive (associated with SCCmec types IVa and V), while 35.7% presented a multidrug resistance (MDR) phenotype. The S. aureus isolates belonged to 11 diverse spa types, including three new (t4539, t6043, t11694) and one singleton (t779), which were assigned to four clonal complexes. Two tst and three luk-F/S-PV carrying strains were identified. All the S. aureus isolates were moderate biofilm producers with diverse combinations of the icaABCD biofilm and icaR regulatory genes. The detection of genetically diverse S. aureus lineages and toxigenic strains highlights the need for improved surveillance of resistant and pathogenic strains in healthcare facilities.}, }
@article {pmid39552765, year = {2024}, author = {Masoumi, N and Keshavarzi, F}, title = {The pattern of antibiotic resistance and distribution of the biofilm-producing Pseudomonas aeruginosa (PelD, PslB) isolated from infectious hospital departments.}, journal = {SAGE open medicine}, volume = {12}, number = {}, pages = {20503121241298826}, pmid = {39552765}, issn = {2050-3121}, abstract = {BACKGROUND: The ability of Pseudomonas aeruginosa to produce biofilm has established it as one of the most significant pathogens. The purpose of this study was to evaluate antimicrobial resistance and conduct a molecular investigation of the virulence genes PslB and PelD in Pseudomonas aeruginosa species isolated from patients.<br><br>METHODOLOGY: One hundred clinical isolates were collected from patients of different age groups who were hospitalized in Kermanshah and Sonqor hospitals. The isolates were obtained through culture on specific media, biochemical confirmatory tests, and gram staining for confirmation. Biofilm production was assessed using an indirect quantification method with crystal violet. Additionally, antibiotic resistance was determined through the disc various method following Clinical and Laboratory Standards Institute guidelines. Finally, the presence of genes related to PlsB and PelD in resistant strains was examined using The polymerase chain reaction (PCR).<br><br>RESULTS: The results indicate that the highest resistance and lowest sensitivity were related to nitrofurantoin 100&#x2009;&#x3bc;g, while the lowest resistance and highest sensitivity were related to cefepime 30&#x2009;mg. Biofilm phenotypes were categorized as weak in 7% (n&#x2009;=&#x2009;7) of isolates, medium in 13% (n&#x2009;=&#x2009;13), and high in 80% (n&#x2009;=&#x2009;80). The PslB and PelD genes were identified in 86% (n&#x2009;=&#x2009;86) and 38% (n&#x2009;=&#x2009;38) of isolates, respectively, while 4% (n&#x2009;=&#x2009;4) did not possess either of these two genes. Additionally, a majority of the isolates exhibited multidrug-resistance (87%) due to their moderate-to-high biofilm formation.<br><br>CONCLUSION: All isolates were capable of producing biofilm. A significant association were between strains with the high biofilm and multidrug-resistance species (p&#x2009;<&#x2009;0.05). Multidrug-resistance (78%) isolates included 28% (n&#x2009;=&#x2009;28) of isolates that were PslB+ PelD+, 45% (n&#x2009;=&#x2009;45) of isolates that were only PslB+, and 5 (n&#x2009;=&#x2009;5) isolates that were only PelD+. A significant relationship was found between the presence of the PslB gene multidrug-resistance and high producer (p&#x2009;<&#x2009;0.05).}, }
@article {pmid39552641, year = {2024}, author = {Sun, C and Zhu, L and Yang, L and Tian, Z and Jiao, Z and Huang, M and Peng, J and Guo, G}, title = {Antimicrobial peptide AMP-17 induces protection against systemic candidiasis and interacts synergistically with fluconazole against Candida albicans biofilm.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1480808}, pmid = {39552641}, issn = {1664-302X}, abstract = {Candida albicans, a common commensal and opportunistic fungal pathogen in humans, can occasionally progress to disseminated candidiasis which is a serious condition with a high morbidity and fatality rate. The emergence of drug-resistant fungal strains compels us to look for an efficient treatment solution. Our earlier studies have demonstrated that the unique antimicrobial peptide AMP-17 from Musca domestica has a strong antifungal impact on C. albicans in vitro. Here, we verified the therapeutic effects of AMP-17 on systemic candidiasis in vivo and the peptide interacts with fluconazole, a common antifungal medication, to treat systemic candidiasis. In the disseminated candidiasis model of Galleria mellonella and mice challenged with C. albicans, AMP-17 increased the survival rates of infected larvae and mice to 66.7 and 75%, respectively. Furthermore, the peptide lowered the load of C. albicans in the infected larvae and the kidneys of the mice by nearly 90%. Additional histological examination and measurements of plasma cytokines showed that the injection of AMP-17 markedly reduced the inflammatory response and balanced cytokine expression. Furthermore, checkerboard micro dilution experiments demonstrated that AMP-17 and fluconazole worked in synergy to inhibit C. albicans in the biofilm mode. According to morphological studies, AMP-17 and fluconazole together decreased the production of hyphae throughout the C. albicans biofilm formation process, loosening the mature biofilms' structure and lowering the amount of carbohydrates in the extracellular matrix (ECM) of the biofilms. Taken together, these results showed that AMP-17 would be a viable treatment for systemic candidiasis and might be a different approach to combating Candida biofilm, either by itself or in conjunction with fluconazole.}, }
@article {pmid39551829, year = {2024}, author = {Idris, AL and Fan, X and Li, W and Pei, H and Muhammad, MH and Guan, X and Huang, T}, title = {Galactose-1-phosphate uridylyltransferase GalT promotes biofilm formation and enhances UV-B resistance of Bacillus thuringiensis.}, journal = {World journal of microbiology &amp; biotechnology}, volume = {40}, number = {12}, pages = {383}, pmid = {39551829}, issn = {1573-0972}, support = {No. 2020N5014//Fujian Science and Technology Projects/ ; No. K1520005A03//Fujian Agriculture and Forestry University Construction Project for Technological Innovation and Service System of Tea Industry Chain/ ; No. 31672084//National Natural Science Foundation of China/ ; }, mesh = {*Biofilms/growth &amp; development/radiation effects ; *Bacillus thuringiensis/genetics/enzymology ; *Ultraviolet Rays ; *Escherichia coli/genetics ; *UTP-Hexose-1-Phosphate Uridylyltransferase/genetics/metabolism ; *Bacterial Proteins/genetics/metabolism ; Ribose/metabolism ; Gene Expression Regulation, Bacterial ; Gene Knockout Techniques ; }, abstract = {Ultraviolet radiation (UV) is a major abiotic stress resulting in relative short duration of Bacillus thuringiensis (Bt) biopesticides in the field, which is expected to be solved by formation of Bt biofilm with higher UV resistance. Therefore, one of the important prerequisite works is to clarify the functions of biofilm-associated genes on biofilm formation and UV resistance of Bt. In this study, comparative genomics and bioinformatic analysis indicated that BTXL6_19475 gene involved in biofilm formation of Bt XL6 was likely to encode a galactose-1-phosphate uridylyltransferase (GalT, E.C. 2.7.7.12). Heterologous expression of the BTXL6_19475 gene in Escherichia coli and detection of its GalT enzyme activity in vitro proved that the gene did encode GalT. Comparing the wild type Bt strain XL6 with galT gene knockout mutant Bt XL6ΔgalT and its complementary strain Bt XL6ΔgalT::19,475, GalT promoted the biofilm formation and enhanced the UV-B resistance of Bt XL6 likely by increasing its D-ribose production and reducing its alanine aryldamidase activity. GalT did not affect the growth and the cell motility of Bt XL6. A regulation map had been proposed to elucidate how GalT promoted biofilm formation and enhanced UV-B resistance of Bt XL6 by the cross-talk between Leloir pathway, Embden-Meyerhof glycolysis pathway and pentose phosphate pathway. Our finding provides a theoretical basis for the efficient use of biofilm genes to improve the UV resistance of Bt biofilms and thus extend field duration of Bt formulations based on biofilm engineering.}, }
@article {pmid39551111, year = {2025}, author = {Krzyżek, P and Dudek, B and Brożyna, M and Krzyżanowska, B and Junka, A}, title = {Galleria mellonella larvae as a model for Helicobacter pylori biofilm formation under antibiotic stress.}, journal = {Microbial pathogenesis}, volume = {198}, number = {}, pages = {107121}, doi = {10.1016/j.micpath.2024.107121}, pmid = {39551111}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; Animals ; *Helicobacter pylori/drug effects/physiology ; *Larva/microbiology/drug effects ; *Anti-Bacterial Agents/pharmacology ; *Clarithromycin/pharmacology ; *Moths/microbiology ; *Microbial Sensitivity Tests ; Microbial Viability/drug effects ; Disease Models, Animal ; Lepidoptera/microbiology ; Stress, Physiological ; Helicobacter Infections/microbiology ; Hemolymph/microbiology ; }, abstract = {Helicobacter pylori is a common Gram-negative bacterium that inhabits the human stomach and causes a variety of gastric pathologies. One of the growing concerns is its dynamic spread of antibiotic resistance, a process in which biofilm formation is involved. Therefore, it is necessary to find an appropriate, high-throughput research model for the in vivo biofilm development by H. pylori. The aim of the current research report was to determine the usefulness of G. mellonella larvae in assessing the survival of a multidrug-resistant, strong biofilm producing H. pylori strain during its exposure to stress caused by clarithromycin. Using infection models lasting for 3 or 6 days, we confirmed the ability of the tested H. pylori strain to survive in the larvae. We noticed that exposure to clarithromycin significantly reduced the number of cultured bacteria relative to the control, although we did not observe any differences in the number of bacteria using time-lapse, live analysis of fluorescently stained larval hemolymph samples. In conclusion, we confirmed that the examined H. pylori strain can produce biofilm in G. mellonella larvae organism and is able to survive exposure to minimal inhibitory concentrations of clarithromycin (established in vitro) in in vivo conditions. Further refinement of methodologies for monitoring the viability of clinical H. pylori strains in the greater wax moth larvae will enhance the accuracy and reliability of this promising research model.}, }
@article {pmid39551108, year = {2025}, author = {Andrade, IB and Alves, V and Correa-Junior, D and Avellar-Moura, I and Soares, J and Sousa Araújo, GR and Pontes, B and Nosanchuk, JD and Almeida-Paes, R and Frases, S}, title = {The biofilm produced by Cryptococcus neoformans protects the fungus from the antifungal and anti-melanin effects of cyclosporine.}, journal = {Microbial pathogenesis}, volume = {198}, number = {}, pages = {107124}, pmid = {39551108}, issn = {1096-1208}, support = {R01 AI171093/AI/NIAID NIH HHS/United States ; R21 AI156104/AI/NIAID NIH HHS/United States ; R41 AI165204/AI/NIAID NIH HHS/United States ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Cryptococcus neoformans/drug effects ; *Melanins/metabolism/biosynthesis ; *Antifungal Agents/pharmacology ; *Cyclosporine/pharmacology ; Virulence Factors/metabolism ; Cryptococcosis/microbiology ; Cell Wall/drug effects/metabolism ; Microbial Sensitivity Tests ; }, abstract = {Understanding Cryptococcus neoformans pathogenesis requires a detailed analysis of the various virulence factors that contribute to its ability to cause disease. Cyclosporine, calcineurin inhibitor, impairs C. neoformans production of a polysaccharide capsule and secretion of urease, which are critical for cryptococcal pathogenesis. Two particularly important virulence factors are the production of cell wall melanin and formation of biofilm. In this study, we investigated cyclosporine's effects on melanin production and biofilm formation in C. neoformans. Initially, we examined melanin production in planktonic cells treated with cyclosporine using an L-DOPA containing melanin-inducing medium. Visual inspection and optical microscopy revealed a notable reduction in the characteristic dark coloration of cultures treated with cyclosporine, which indicate decreased melanin production in daughter cells compared to mother cells. Spectrophotometric analysis also demonstrated a significantly altered ultraviolet-visible (UV/vis) absorption spectra in cyclosporine-treated yeast cells, indicative of structural changes in melanin. Additionally, cyclosporine-treated cells exhibited reduced conductance (P-value < 0.0001), suggesting altered cellular ionic properties. The impact of cyclosporine on biofilm formation and mature biofilm disruption was also assessed. Despite cyclosporine's efficacy in modifying virulence factors during planktonic growth, cyclosporine did not inhibit biofilm formation or melanization under biofilm growth conditions, nor did it disrupt mature biofilms in terms of biomass or metabolic activity. However, there was a significant reduction in extracellular matrix production in cyclosporine-treated non-melanized biofilms. Our findings underscore the complex interplay between cyclosporine and C. neoformans, highlighting its differential effects on melanization and biofilm dynamics, which provides new insights into the shortcomings of cyclosporin for combatting cryptococcosis and informs pathways for future therapeutic strategies against cryptococcosis.}, }
@article {pmid39549959, year = {2025}, author = {Han, YL and Shi, LD and Zhao, HP}, title = {Achieving efficient autotrophic nitrogen removal in anaerobic membrane bioreactor plus membrane aerated biofilm reactor by regulating nutrient ratios.}, journal = {Bioresource technology}, volume = {416}, number = {}, pages = {131832}, doi = {10.1016/j.biortech.2024.131832}, pmid = {39549959}, issn = {1873-2976}, mesh = {*Bioreactors ; *Nitrogen ; *Biofilms ; *Membranes, Artificial ; Anaerobiosis ; *Autotrophic Processes ; *Biological Oxygen Demand Analysis ; Sulfates/metabolism ; Sewage/microbiology ; Ammonium Compounds/metabolism ; Denitrification ; Nutrients/metabolism ; }, abstract = {It is feasible to integrate an anaerobic membrane bioreactor with a membrane aerated biofilm reactor to efficiently implement the sulfate reduction, simultaneous nitrification and autotrophic denitrification process. However, the effect of parameters on nutrient removal and environmental impacts of the process are unclear. In this study, the reactor performance was mainly influenced by the chemical oxygen demand to sulfate (COD/S) ratio and the ammonium to sulfate (N/S) ratio in long-term operation. Significant models were developed to optimize the two factors using the response surface methodology. Under optimal conditions (COD/S ratio of 2.5 and N/S ratio of 0.3), the system could remove above 86 % COD, 99 % ammonium, and 92 % total inorganic nitrogen. Moreover, this process could reduce energy consumption by 30 % and global warming potential by 50 % compared with traditional anaerobic/oxic activated sludge process. These findings provide guidance for the application of this technology in sulfate-containing municipal sewage treatment.}, }
@article {pmid39549924, year = {2025}, author = {Zhi, K and Zhou, X and Gao, T and Liu, K and Wang, Z and Cai, Y and Wang, Z and Wang, S and Liu, J and Liu, D and Ying, H}, title = {Engineering Saccharomyces cerevisiae for continuous secretory production of hEGF in biofilm.}, journal = {Journal of biotechnology}, volume = {397}, number = {}, pages = {1-10}, doi = {10.1016/j.jbiotec.2024.11.007}, pmid = {39549924}, issn = {1873-4863}, mesh = {*Biofilms/growth &amp; development ; *Saccharomyces cerevisiae/genetics/metabolism ; *Fermentation ; *Epidermal Growth Factor/genetics/metabolism ; Humans ; Saccharomyces cerevisiae Proteins/genetics/metabolism ; Metabolic Engineering/methods ; Promoter Regions, Genetic/genetics ; }, abstract = {Human epidermal growth factor (hEGF) plays a crucial role in promoting cell growth and has various clinical applications. Due to limited natural sources and the high cost of chemical synthesis, researchers are now exploring genetic engineering as a potential method for hEGF production. In this particular study, a novel hEGF expression system was developed using Saccharomyces cerevisiae. This system involved optimizing the promoter and signal peptide and deleting protease-coding genes PEP4, PRB1, and YAP3, overexpressing chaperones KAR2 and PDI1 in the protein secretion pathway, which led to a 2.01-fold increase in hEGF production compared to the wild type strain. Furthermore, biofilm-forming genes FLO11 and ALS3 were integrated to create a biofilm strain with adhesive properties. A biofilm-based immobilized continuous fermentation model was established to leverage the characteristics of this biofilm strain. Each batch of this model yielded 130 mg/L of hEGF, with a production efficiency of 2.71 mg/L/h - surpassing the production efficiency of traditional free fermentation (1.62 mg/L/h). This study presents a promising fermentation model for efficient hEGF production based on biofilm characteristics, offering valuable insights for the application of biofilm fermentation in the production of small molecule peptides.}, }
@article {pmid39549521, year = {2024}, author = {Truong, YL and Rosenblatt, J and Gerges, B and Jiang, Y and Raad, I}, title = {Eradication of Candida auris biofilm in vitro by a polygalacturonic and caprylic acid wound ointment.}, journal = {Journal de mycologie medicale}, volume = {34}, number = {4}, pages = {101519}, doi = {10.1016/j.mycmed.2024.101519}, pmid = {39549521}, issn = {1773-0449}, mesh = {*Biofilms/drug effects ; *Caprylates/pharmacology ; *Ointments ; Humans ; *Antifungal Agents/pharmacology/administration &amp; dosage ; *Pectins/pharmacology/administration &amp; dosage ; *Candida auris/drug effects ; Microbial Sensitivity Tests ; Candidiasis/drug therapy/microbiology ; Wound Infection/microbiology/drug therapy/prevention &amp; control ; Honey ; }, abstract = {Candida auris is a rapidly spreading virulent pathogen frequently resistant to multiple antifungal drugs that can form biofilms and infect wounds. Hence, there is a need for C. auris wound treatments not posing risks for developing antifungal resistance. We tested the ability of a polygalacturonic and caprylic acid ointment (PG+CAP) to rapidly eradicate C. auris biofilms within 2-hour exposures in an in vitro model. Medical-grade honey (MediHoney) wound ointment was used as a comparator. Nine different C. auris strains were tested. PG+CAP eradicated biofilms of 8 of the 9 tested strains and produced a > 5-log10 reduction of the ninth. MediHoney produced reductions ranging from 2 to 4 log10 without fully eradicating any strains. The differences between PG+CAP and MediHoney were statistically significant (p < 0.05). These results suggest that PG+CAP is a promising antimicrobial ointment warranting further in vivo study in wounds which may be colonized by C. auris biofilms.}, }
@article {pmid39548688, year = {2024}, author = {Osiro, KO and Hashemi, N and Brango-Vanegas, J and Oliveira, SMD and Franco, OL}, title = {Emerging peptide-based technology for biofilm control.}, journal = {Expert opinion on biological therapy}, volume = {24}, number = {12}, pages = {1311-1315}, doi = {10.1080/14712598.2024.2430623}, pmid = {39548688}, issn = {1744-7682}, }
@article {pmid39547568, year = {2025}, author = {Miao, L and Li, W and Li, C and Adyel, TM and You, G and Xu, Y and Wu, J and Yao, Y and Kong, M and Feng, J and Hou, J}, title = {Effects of reduced flow gradient on benthic biofilm communities' ecological network and community assembly.}, journal = {Environmental research}, volume = {264}, number = {Pt 1}, pages = {120362}, doi = {10.1016/j.envres.2024.120362}, pmid = {39547568}, issn = {1096-0953}, mesh = {*Biofilms/growth &amp; development ; *Rivers/microbiology ; *Microbiota ; Fungi/physiology ; Bacteria/genetics ; Water Movements ; Biodiversity ; Ecosystem ; }, abstract = {The intensification of human activities has led to flow reduction and cut-off in most global rivers, seriously affecting riverine organisms and the biogeochemical processes. As key indicators of river ecosystems' structure and function, benthic biofilms play a critical role in driving primary production and material cycling in rivers. This research aimed to investigate the characteristics of microbial communities' complexity and stability during river flow reduction. Benthic biofilms were grown in artificial channels and subjected to eight gradients of flow reduction (represented by flow velocity from 0.4 to 110 cm/s). Biofilms' biodiversity, ecological networks and community assembly of bacteria, fungi and algae were investigated by high-throughput sequencing. Results showed significant differences in community composition and structure under different flow conditions. The eight flow gradients' microbial communities were divided into three groups: low, medium and high flows. The flow reduction led to significant decreases in bacterial and fungal communities' Chao1 index. Low flow conditions enriched the bacterial phyla Oxyphotobacteria, Alphaproteobacteria and Mollicutes, but significantly decreased the fungal phylum Chytridiomycota. Lowering flow reduced the fungal network's number of nodes and increased the algal network's number of edges. Cross-domain interactions network analysis showed a gradual increase in node and edge numbers with decreasing flow, while decreasing average path length. The neutral model predicted stochastic processes primarily drove biofilm community assembly, and that model's explanations decreased as the flow gradient decreased. The null model analysis revealed diffusion limitation as the most common stochastic ecological process for bacterial and algal communities, with reduced flow reducing heterogeneous selection and increasing diffusion-limited processes. This study provides an in-depth analysis of flow reduction's effects on biofilm communities' ecological networks and community assembly.}, }
@article {pmid39546838, year = {2025}, author = {Shafaie, E and Mahdizadeh, MH and Amirian, M and Askari, P and Yousefi, M}, title = {A study of clinical and bacteriological characteristics of Klebsiella pneumoniae isolates in Birjand, South-East Iran: Hypervirulent phenotype, biofilm formation, virulence factors, and antibiotic resistance.}, journal = {Diagnostic microbiology and infectious disease}, volume = {111}, number = {1}, pages = {116595}, doi = {10.1016/j.diagmicrobio.2024.116595}, pmid = {39546838}, issn = {1879-0070}, mesh = {*Biofilms/growth &amp; development/drug effects ; *Klebsiella pneumoniae/pathogenicity/drug effects/genetics/isolation &amp; purification ; *Virulence Factors/genetics ; Humans ; Iran/epidemiology ; *Klebsiella Infections/microbiology/epidemiology ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology ; Female ; Middle Aged ; Male ; Adult ; Virulence/genetics ; Drug Resistance, Multiple, Bacterial/genetics ; Aged ; Young Adult ; Phenotype ; Adolescent ; Child ; Aged, 80 and over ; Child, Preschool ; }, abstract = {This study assessed antimicrobial susceptibility, biofilm formation, hypervirulence traits, and virulence-related genes in K. pneumoniae. 119 isolates underwent antibiotic susceptibility testing using the Kirby-Bauer method, biofilm assessment through Congo red agar and Microtiter plate assays, PCR for various genes, and the String test for hypermucoviscosity. Clinical characteristics and virulence factors of hypervirulent (hvKP) were compared to classic K. pneumoniae (cKP) strains. Among the isolates, 77.3% were multi-drug resistant (MDR), and 83.2% showed biofilm-forming ability, with a higher MDR incidence in biofilm producers. A significant correlation was found between biofilm formation and the presence of the blaCTX-M15 gene. Genes luxS, mrkA, pgaA, and wzm were significantly related to biofilm production. Three K. pneumoniae (2.5%) were identified as hvKP, with higher prevalence of capsular serotypes K1/K2 and virulence-related genes iuc, rmpA, and rmpA2 than cKP. The study underscores the importance of surveillance and stewardship in combating MDR, biofilm-forming, highly virulent K. pneumoniae.}, }
@article {pmid39543628, year = {2024}, author = {Ye, Y and Zheng, Q and Wang, Z and Wang, S and Lu, Z and Chu, Q and Liu, Y and Yao, K and Wei, B and Han, H and Chen, H and Zhang, X}, title = {Metal-phenolic nanoparticles enhance low temperature photothermal therapy for bacterial biofilm in superficial infections.}, journal = {Journal of nanobiotechnology}, volume = {22}, number = {1}, pages = {713}, pmid = {39543628}, issn = {1477-3155}, support = {520030533//National Natural Science Foundation of China/ ; 82271064//National Natural Science Foundation of China/ ; 32372757//National Natural Science Foundation of China/ ; 2024C03073//Key Research and Development Project of Zhejiang Province/ ; 2023C02040//Key Research and Development Project of Zhejiang Province/ ; LR23H120001//Natural Science Foundation of Zhejiang Province/ ; CAAS-ASTIP-2021-TRI//innovative Program of Chinese Academy of Agricultural Sciences/ ; }, mesh = {*Biofilms/drug effects ; Animals ; *Photothermal Therapy/methods ; *Methicillin-Resistant Staphylococcus aureus/drug effects ; *Metal Nanoparticles/chemistry ; Mice ; *Gold/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; Staphylococcal Infections/drug therapy ; Catechin/analogs &amp; derivatives/pharmacology/chemistry ; Female ; Keratitis/drug therapy/microbiology ; Wound Healing/drug effects ; Reactive Oxygen Species/metabolism ; Mice, Inbred BALB C ; Humans ; }, abstract = {Bacterial infections, especially induced by multidrug-resistant pathogens, have become a significant global health concern. In the infected tissues, biofilms not only serve as a source of nutrients but also act as protective barriers that impede antibiotic penetration. Herein, we developed tea polyphenols epigallocatechin gallate (EGCG) Au nanoparticles (E-Au NPs) through direct one-step self-assembly methods by EGCG chelating with Au ions to eradicate antibiotic-resistant bacteria methicillin-resistant Staphylococcus aureus (MRSA) and prevent the formation of biofilm under near-infrared (NIR) irradiation. The outstanding antibacterial effect involved in mild photothermal therapy, reactive oxygen species production, pathogenicity-related genes regulation, and quinoprotein formation that were specific to the polyphenol-based NPs. The excellent antibacterial and anti-inflammatory therapeutic efficacy of E-Au NPs was validated and topically applied in murine MRSA-infected skin wounds and keratitis model in vivo to kill bacteria, reduce the inflammation response and promote wound healing. Furthermore, the ophthalmic and systemic biosafety profiles were thoroughly evaluated while no significant side effects were revealed achieving a balance between high-efficiency antibacterial properties and biocompatibility. This study provides an effective therapeutic agent of metal-phenolic materials for superficial tissue infection with favorable prognosis and potential in clinical translation.}, }
@article {pmid39543581, year = {2024}, author = {Karimi, Y and Rashidipour, M and Iranzadasl, M and Ahmadi, MH and Sarabi, MM and Farzaneh, F}, title = {Biofilm targeting with chitosan-based nanohydrogel containing Quercus infectoria G. Olivier extract against Streptococcus mutans: new formulations of a traditional natural product.}, journal = {BMC complementary medicine and therapies}, volume = {24}, number = {1}, pages = {398}, pmid = {39543581}, issn = {2662-7671}, mesh = {*Streptococcus mutans/drug effects ; *Biofilms/drug effects ; *Plant Extracts/pharmacology/chemistry ; *Quercus ; *Hydrogels/chemistry ; *Chitosan/chemistry/pharmacology ; Humans ; Anti-Bacterial Agents/pharmacology/chemistry ; Microbial Sensitivity Tests ; }, abstract = {BACKGROUND: Biofilm formation has a crucial role in the cariogenic virulence of Streptococcus mutans, which leads to resistance to common antibacterials. The antimicrobial resistance crisis has led to increased research about traditional natural products.<br><br>PURPOSE: Quercus infectoria extract (QI extract) and nano hydrogels containing QI extract (QI-NH) and tannic acid (TA-NH) were evaluated against this pathogen.<br><br>METHODS: QI extract was analyzed by HPLC and the physiological characteristics of nanohydrogels were assessed by SEM, FTIR, zeta potential, DLS and determination of release kinetics and encapsulation efficiency. Determination of MIC and MBC of the material and their anti-biofilm effect was done by the microtiter method and on the extracted tooth surface. The properties of extracts and nano hydrogels in the expression of genes codifying glucosyltransferases (gtfB, gtfC and gtfD) and glucan binding protein B (gbpB) were quantified. Their toxicity was tested by the MTT method against the KB cell line.<br><br>RESULTS: According to HPLC, 55.18% of QI extract contained TA. The encapsulation efficiency of QI-NH and TA-NH was equal to 60% and 80%, respectively. SEM and FTIR exhibited that QI extract and TA were successfully entrapped in the networks resulting from the chemical bonding of chitosan and TPP. The average size of QI-NH and TA-NH was 70.45 and 58.43&#xa0;nm, and their zeta potential was 6.17&#x2009;&#xb1;&#x2009;2.58 and 0.25&#x2009;&#xb1;&#x2009;0.03 mv, respectively. PDI&#x2009;<&#x2009;0.3 of nano hydrogels indicated the favorable polydispersity of nanohydrogels. MIC of QI extract, QI-NH and TA-NH were 937.5, 30 and 10&#xa0;&#xb5;g/ml, respectively. Also their MBIC50 was 35.1, 2.1 and 0.95&#xa0;&#xb5;g/ml, respectively, and the extracts and nano hydrogels restrained the biofilm maturation on enamel. The pivotal genes of S. mutans in biofilm formation were significantly less expressed by treatment with QI-NH and TA-NH than others. Based on the MTT test, QI-NH had less acute toxicity than QI extract and TA-NH. IC50 of QI-NH was calculated as 775.4&#xa0;&#xb5;g/ml, while it was equal to 3.12&#xa0;&#xb5;g/ml for chlorhexidine as a common antibacterial agent.<br><br>CONCLUSION: QI-NH, a new formulation derived from traditional anti-caries, can be a safe and efficient option to combat dental biofilm.}, }
@article {pmid39542869, year = {2024}, author = {Shewa, WA and Sun, L and Bossy, K and Dagnew, M}, title = {Biofilm characterization and dynamic simulation of advanced rope media reactor for the treatment of primary effluent.}, journal = {Water environment research : a research publication of the Water Environment Federation}, volume = {96}, number = {11}, pages = {e11150}, pmid = {39542869}, issn = {1554-7531}, support = {//Natural Sciences and Engineering Research Council of Canada/ ; //MITACS/ ; }, mesh = {*Biofilms ; *Bioreactors ; *Waste Disposal, Fluid/methods ; Models, Theoretical ; Nitrates ; Wastewater/chemistry ; Ammonia/chemistry ; Water Purification/methods ; }, abstract = {Biofilm modeling is inherently complex, often requiring multiple assumptions and simplifications. In biofilm modeling, default or literature-based values in biofilm systems are usually used to estimate biofilm parameters, including boundary layer, biofilm density, thickness, attachment, and detachment rates. This study aimed to characterize and model the biofilm of a specific rope-type fixed media system, removing carbon and total inorganic nitrogen, coupled with sensitivity analysis. Among the five model parameters, the sensitivity analysis of this study showed that boundary layer thickness is the most influential parameter for predicting effluent ammonia and nitrate concentrations, and biofilm density is most sensitive with respect to effluent chemical oxygen demand (COD). The least sensitive parameter is the detachment rate. Based on the calculated mean absolute error (MAE) and root mean squared error (RMSE), the calibrated BioCord fixed-film reactor (BFFR) model accurately predicted effluent ammonium and dissolved oxygen (DO) in the continuously aerated bench-scale reactor (R1) and failed to predict well in the intermittently aerated bench-scale reactor (R2). RMSE values calculated for NH3-N and DO in R1 are 0.95 and 0.53 mg/L, respectively. In the BioCord pilot plant's case, ammonium-N predicted by the model fit the measured values well, while it overpredicted DO concentrations. PRACTITIONER POINTS: Fixed biofilm BioCord reactors were studied for primary effluent treatment. A methodology was developed to characterize biofilms. Boundary layer thickness is the most influential parameter for predicting effluent ammonia and nitrate concentrations. Biofilm density is the most sensitive parameter with respect to effluent COD. The calibrated BFFR model can predict effluent ammonium, nitrite, and nitrate-nitrogen.}, }
@article {pmid39542331, year = {2024}, author = {Valizadeh, R and Zandi, M and Ganjloo, A and Dardmeh, N}, title = {Eco-friendly nanocomposite biofilm based on sage seed gum/gelatin/TiO2: Fabrication and characterization.}, journal = {International journal of biological macromolecules}, volume = {283}, number = {Pt 1}, pages = {137558}, doi = {10.1016/j.ijbiomac.2024.137558}, pmid = {39542331}, issn = {1879-0003}, mesh = {*Gelatin/chemistry ; *Nanocomposites/chemistry ; *Titanium/chemistry ; *Seeds/chemistry ; *Biofilms/drug effects ; *Plant Gums/chemistry ; Salvia officinalis/chemistry ; Permeability ; Steam ; Tensile Strength ; Anti-Bacterial Agents/chemistry/pharmacology ; }, abstract = {In the current study, the sage seed gum/gelatin-TiO2 (SG/Ge-TiO2) nanocomposite films were prepared. Their physical, mechanical, chemical, barrier, surface, structural, and microbial characteristics are determined as a function of different ratios of sage seed gum (SG) to gelatin (1 to 2, 2 to 1 and 1 to 1) and different concentrations of TiO2 nanoparticles (0, 2, 4 % based on biopolymer (w/v)). The results indicated increases in the tensile strength, elongation at break, thickness, brightness (L*), whiteness index (WI), and contact angle, as gelatin content and concentration of TiO2 nanoparticles increase. In addition, the increases of TiO2 nanoparticles and the increased content of SG lead to an increase in the surface roughness of the films. As the gelatin content and the concentration of TiO2 nanoparticles increased, the barrier characteristics against water vapor, oxygen, and light increased, so that the water vapor, oxygen, and light permeability in the SG 1-Ge 2-4 % film decreased by 66.93 %, 80.89 %, and 47.43 %, respectively, compared to the SG 2 Ge 1-0 % film. According to the results of structural and thermal investigation, the crystallinity degree in the films increased as the gelatin content and the concentration of TiO2 nanoparticles increased, resulting in the enhanced thermal stability of the film. The addition of TiO2 nanoparticles brought about antimicrobial characteristics in the film, with no significant effect on the antioxidant activity and total phenol content (p > 0.05). The results indicated that SG-Ge-TiO2 bionanocomposite films (especially SG 1-Ge 2-4 %) can be considered a suitable option for active food packaging as well as medical applications (e.g. active wound adhesive) due to its favorable characteristics.}, }
@article {pmid39540969, year = {2024}, author = {Srihawan, O and Panichuttra, A and Lertchirakarn, V and Matangkasombut, O}, title = {Efficacy of chitosan root canal medicament against cross-kingdom dual-species biofilm of Candida albicans and Enterococcus faecalis in an in vitro root-canal model.}, journal = {Odontology}, volume = {}, number = {}, pages = {}, pmid = {39540969}, issn = {1618-1255}, support = {Ratchadaphiseksomphot Endowment Fund//Chulalongkorn University/ ; }, abstract = {Infection of the root canals with cross-kingdom biofilm of Candida albicans (C. albicans) and Enterococcus faecalis (E. faecalis) causes more inflammation and is resistant to conventional medication. This study aimed to evaluate the efficacy of chitosan paste (chitosan + propylene glycol (PG)) against this dual-species biofilm in comparison to calcium hydroxide (Ca(OH)2) in the root canals of human teeth. Fifty extracted single-rooted human teeth were prepared and inoculated with C. albicans and E. faecalis, and incubated for 3 days for biofilm formation. Four experimental groups (N = 10 each) were applied with different root canal medications for 7 days, including (1) No medication (negative control); (2) Ca(OH)2 + distilled water; (3) PG (vehicle control) and (4) chitosan + PG. The efficacy of root canal medicaments was assessed by determining the percentage of remaining colony-forming units (CFUs) of viable microorganisms in intracanal dentin. The dentin was collected, serially diluted, and spread on solid media for colony count. The biofilm structure in root canals at 3 days and 10 days (ie. before and after treatments) were observed with scanning electron microscopy (SEM) at 5000× and 10,000× magnifications. Data were analyzed using Welch's ANOVA and Games-Howell post-hoc test (α = 5%). The results show that Chitosan + PG group had a significantly lower percentage of remaining microorganisms when compared to PG, Ca(OH)2, and negative control groups (P-value = 0.015, 0.005, and < 0.001, respectively). Consistently, SEM showed the lowest amount of remaining biofilm in Chitosan + PG group. Thus, Chitosan + PG paste was the most efficacious root canal medicament against dual-species biofilm of C. albicans and E. faecalis in this model.}, }
@article {pmid39538008, year = {2024}, author = {Landa, G and Clarhaut, J and Buyck, J and Mendoza, G and Arruebo, M and Tewes, F}, title = {Impact of mixed Staphylococcus aureus-Pseudomonas aeruginosa biofilm on susceptibility to antimicrobial treatments in a 3D in vitro model.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {27877}, pmid = {39538008}, issn = {2045-2322}, support = {PID2020-113987RB-I00 and PDC2021-121405-I00//Ministerio de Ciencia e Innovaci&#xf3;n/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Staphylococcus aureus/drug effects/physiology ; *Pseudomonas aeruginosa/drug effects/physiology ; *Chlorhexidine/pharmacology ; *Microbial Sensitivity Tests ; *Coculture Techniques ; Anti-Bacterial Agents/pharmacology ; Thymol/pharmacology ; Anti-Infective Agents, Local/pharmacology ; Humans ; }, abstract = {Staphylococcus aureus and Pseudomonas aeruginosa are the most common bacteria co-isolated from chronic infected wounds. Their interactions remain unclear but this coexistence is beneficial for both bacteria and may lead to resistance to antimicrobial treatments. Besides, developing an in vitro model where this coexistence is recreated remains challenging, making difficult their study. The aim of this work was to develop a reliable polymicrobial in vitro model of both species to further understand their interrelationships and the effects of different antimicrobials in coculture. In this work, bioluminescent and fluorescent bacteria were used to evaluate the activity of two antiseptics (chlorhexidine and thymol) against these bacteria planktonically grown, or when forming single and mixed biofilms. At the doses tested (0.4-1,000 mg/L), thymol showed selective antimicrobial action against S. aureus in planktonic and biofilm states, in contrast with chlorhexidine which exerted antimicrobial effects against both bacteria. Furthermore, the initial conditions for both bacteria in the co-culture determined the antimicrobial outcome, showing that P. aeruginosa impaired the proliferation and metabolism of S. aureus. Moreover, S. aureus showed an increased tolerance against antiseptic treatments when co-cultured, attributed to the formation of a thicker mixed biofilm compared to those obtained when monocultured, and also, by the reduction of S. aureus metabolic activity induced by diffusible molecules produced by P. aeruginosa. This work underlines the relevance of polymicrobial populations and their crosstalk and microenvironment in the search of disruptive and effective treatments for polymicrobial biofilms.}, }
@article {pmid39537632, year = {2024}, author = {Arndt, F and Siems, K and Walker, SV and Bryan, NC and Leuko, S and Moeller, R and Boschert, AL}, title = {Systematic screening of 42 vancomycin-resistant Enterococcus faecium strains for resistance, biofilm, and desiccation in simulated microgravity.}, journal = {NPJ microgravity}, volume = {10}, number = {1}, pages = {103}, pmid = {39537632}, issn = {2373-8065}, abstract = {Vancomycin-resistant Enterococcus faecium (VRE) presents significant challenges in healthcare, particularly for hospitalized and immunocompromised patients, including astronauts with dysregulated immune function. We investigated 42 clinical E. faecium isolates in simulated microgravity (sim. µg) using a 2-D Clinostat, with standard gravity conditions (1 g) as a control. Isolates were tested against 22 antibiotics and characterized for biofilm formation and desiccation tolerance. Results showed varied responses in minimum inhibitory concentration (MIC) values for seven antibiotics after sim. µg exposure. Additionally, 55% of isolates showed a trend of increased biofilm production, and 59% improved desiccation tolerance. This investigation provides initial insights into E. faecium's changes in response to simulated spaceflight, revealing shifts in antibiotic resistance, biofilm formation, and desiccation tolerance. The observed adaptability emphasizes the need to further understand VRE's resilience to microgravity, which is crucial for preventing infections and ensuring crew health on future long-duration space missions.}, }
@article {pmid39536603, year = {2025}, author = {Hasan, MI and Aggarwal, S}, title = {Matrix matters: How extracellular substances shape biofilm structure and mechanical properties.}, journal = {Colloids and surfaces. B, Biointerfaces}, volume = {246}, number = {}, pages = {114341}, doi = {10.1016/j.colsurfb.2024.114341}, pmid = {39536603}, issn = {1873-4367}, mesh = {*Biofilms/drug effects ; *Staphylococcus epidermidis/physiology/drug effects ; *Extracellular Polymeric Substance Matrix/metabolism/chemistry ; Microscopy, Atomic Force ; Elastic Modulus ; Spectroscopy, Fourier Transform Infrared ; }, abstract = {Biofilms possess unique mechanical properties that are vital to their stability and function. Biofilms are made of extracellular polymeric substances (EPS) secreted by microorganisms and comprise polysaccharides, proteins, extracellular DNA (eDNA), and lipids. EPS is the primary contributor and driver of the biofilm structure and mechanical properties such as stiffness, cohesion, and adhesion. EPS enhances the elasticity and viscosity of biofilms, allowing them to withstand mechanical stresses, shear forces, and deformation. Therefore, biofilms are notoriously difficult to remove and can result in billions of dollars in losses for various industries due to their adverse effects, such as contamination, pressure loss, and corrosion. As a result, it is essential to comprehend the mechanical properties of biofilms to control or remove them in various scenarios. We undertook a fundamental study to determine the relationship between individual EPS components and biofilm mechanical properties. In this study, a CDC biofilm reactor was used to grow pure culture biofilms (Staphylococcus epidermidis) which were treated with six EPS modifier agents (Ca[2+], Mg[2+], periodic acid, protease K, lipase, and DNAase I) to modify or cleave specific EPS components. The mechanical properties (Young's Modulus) of treated biofilms were subsequently tested using atomic force microscopy (AFM), the biofilm EPS functional groups were measured via the Fourier transform infrared (FTIR) spectroscopy, and biofilm structural characteristics using confocal imaging. The FTIR results showed that EPS modifier agents successfully reduced their target EPS components. Similarly, the confocal microscopic analysis results showed that most of these modifier agents (except lipase) significantly reduced (P-value <0.05) the biovolume and thickness of treated biofilms. Conversely, most of these modifier agents (except protease K) significantly increased (P-value <0.05) the roughness coefficient of the biofilms. Finally, data from AFM showed that biofilm mechanical properties (Young's modulus) significantly (P-value <0.05) changed with their EPS composition. These results have significant ramifications for biofilm management and control in myriad scenarios.}, }
@article {pmid39536199, year = {2024}, author = {Alencar, KP and Peixoto, DF and Máximo, FDN and Farias, IAP and Sampaio, FC}, title = {Dental biofilm acidogenicity induced by pediatric oral medications: a double-blind randomized clinical trial.}, journal = {Brazilian oral research}, volume = {38}, number = {}, pages = {e107}, pmid = {39536199}, issn = {1807-3107}, mesh = {Humans ; *Biofilms/drug effects ; Double-Blind Method ; Adolescent ; *Cross-Over Studies ; Hydrogen-Ion Concentration ; Male ; Female ; Young Adult ; Analysis of Variance ; Time Factors ; Area Under Curve ; Reference Values ; Sucrose ; Dental Plaque/microbiology ; }, abstract = {The aim of this study was to evaluate in vivo dental biofilm acidogenicity induced by nine long-term pediatric oral liquid medications (OLMs). A double-blind crossover randomized clinical trial was conducted with 12 individuals aged 18 to 22 years who had good oral hygiene (OSI < 1.1) and a DMFT index of less than 12. Each participant was exposed to nine OLMs and a 10% sucrose solution (positive control) as part of the crossover design. The pH of the dental biofilm was measured with a Beetrode® microelectrode at 0, 5, 10, 15, 20, 25, and 30 min. Statistical analysis was performed to determine the minimum pH and the area under the curve (AUC). One-way ANOVA was utilized, and the significance level was set at 0.05. Pediatric OLMs caused a sucrose-like decrease in biofilm pH, regardless of therapeutic class (p > 0.05). The mean ± standard deviation of the AUC ranged from 16.26 ± 11.59 (cetirizine) to 39.22 ± 20.81 (azithromycin), with no statistically significant difference compared to sucrose (25.22 ± 6.97) (p > 0.05). The findings suggest that pediatric OLMs contribute to dental biofilm acidogenicity, with a more pronounced effect induced by medications used for respiratory diseases and also by antibiotics.}, }
@article {pmid39534299, year = {2024}, author = {Nguyen, BVG and Tran, LXT and Vo, TH and Nguyen-Ha, AT and Le, MT and Nguyen, PV}, title = {Biofilm formation and drug susceptibility of biofilm Candida spp. clinically isolated from nasopharyngeal cancer patients in Vietnam.}, journal = {Iranian journal of microbiology}, volume = {16}, number = {5}, pages = {698-707}, pmid = {39534299}, issn = {2008-3289}, abstract = {BACKGROUND AND OBJECTIVES: The biofilm formation has been widely recognized as one of the main mechanisms of antimicrobial resistance development in microorganisms. However, few studies are focusing on this phenomenon in Candida spp. in clinical settings, especially on immuno-compromised patients.<br><br>MATERIALS AND METHODS: In this study, both the rate of biofilm formation in those patients and its drug susceptibility in initial and mature biofilm were assessed using crystal violet assay and dilution method.<br><br>RESULTS: The results demonstrated that the biofilm formation rate was similar between albicans and non-albicans Candida. However, the biofilm formation capacity was more pronounced in non-albicans Candida, especially, C. glabrata. As expected, there was a significant relationship between biofilm formation and drug resistance. In addition, our study reconfirmed that the age of high concentration of antifungal agents only affected Candida before its biofilm formation regardless of its biofilm formation capacity. In the contrary, once the biofilm was formed even elevated drug concentrations did not show sufficient efficacy, highlighting a need for high dosage at the early stage of treatment for those patients.<br><br>CONCLUSION: The results of this study highlighted the importance of using appropriate antifungal agents for Candida treatment before the formation of biofilm.}, }
@article {pmid39529679, year = {2024}, author = {Jenjitwanich, A and Marx, H and Sauer, M}, title = {Characterization of the metabolism of the yeast Yarrowia lipolytica growing as a biofilm.}, journal = {FEMS microbes}, volume = {5}, number = {}, pages = {xtae026}, pmid = {39529679}, issn = {2633-6685}, abstract = {Yarrowia lipolytica is a well-characterized yeast with remarkable metabolic adaptability. It is capable of producing various products from different carbon sources and easily switching between planktonic and biofilm states. A biofilm represents a natural means of cell immobilization that could support continuous cultivation and production processes, such as perfusion cultivation. However, the metabolic activities of Y. lipolytica in biofilms have not yet been studied in detail. Therefore, this study aimed to compare the metabolic activities of Y. lipolytica in biofilm and planktonic states. Conventionally, a stirred tank bioreactor was used to cultivate Y. lipolytica in a planktonic state. On the other hand, a trickle bed bioreactor system was used for biofilm cultivation. The low pH at 3 was maintained to favor polyol production. The accumulation of citric acid was observed over time only in the biofilm state, which significantly differed from the planktonic state. Although the biofilm cultivation process has lower productivity, it has been observed that the production rate remains constant and the total product yield is comparable to the planktonic state when supplied with 42% oxygen-enriched air. This finding indicates that the biofilm state has the potential for continuous bioprocessing applications and is possibly a feasible option.}, }
@article {pmid39535494, year = {2024}, author = {Miedema, TP and Grooters, KE and Cleary, IA}, title = {The Effects of Carbonate on Candida albicans Filamentation, Biofilm Formation, and Antifungal Resistance.}, journal = {MicrobiologyOpen}, volume = {13}, number = {6}, pages = {e70008}, pmid = {39535494}, issn = {2045-8827}, support = {//This work was supported in part by the Office of Undergraduate Research and Scholarship at GVSU and a Kindschi Undergraduate Research Fellowship in the Sciences to TPM./ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Candida albicans/drug effects/growth &amp; development/physiology ; *Antifungal Agents/pharmacology ; *Drug Resistance, Fungal ; *Carbonates/pharmacology ; Microbial Sensitivity Tests ; Humans ; Hyphae/drug effects/growth &amp; development ; }, abstract = {Candida albicans, a member of the normal microbial population of healthy humans, is an opportunistic pathogen that can cause serious disease in immunocompromised patients. An important virulence factor of C. albicans is the formation of biofilms. These organized communities of cells are efficient at attaching to host cells and implanted medical devices. Carbonate has been studied as an agricultural antifungal agent, and here we demonstrate that carbonate can affect filamentation, biofilm formation, and antifungal drug resistance in C. albicans.}, }
@article {pmid39531471, year = {2024}, author = {Faboro, T and Daniel, J}, title = {Biofilm formation and polar lipid biosynthesis in Mycobacterium abscessus are inhibited by naphthylmethylpiperazine.}, journal = {PloS one}, volume = {19}, number = {11}, pages = {e0311669}, pmid = {39531471}, issn = {1932-6203}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Piperazines/pharmacology ; *Mycobacterium abscessus/drug effects/metabolism ; *Anti-Bacterial Agents/pharmacology ; Microbial Sensitivity Tests ; Naphthoquinones/pharmacology ; Lipid Metabolism/drug effects ; Bacterial Proteins/metabolism/antagonists &amp; inhibitors ; Lipids/biosynthesis ; }, abstract = {Mycobacterium abscessus is a biofilm-forming, non-tuberculous mycobacterium that is highly resistant to antibiotics. Bacterial efflux pumps contribute to biofilm formation, export of biofilm-associated lipids and antibiotic tolerance. The Resistance Nodulation Cell Division (RND) and ATP-Binding Cassette (ABC) families of efflux pumps export lipids to the mycobacterial cell surface. 1-(1-naphthyl methyl)-piperazine (NMP) is a chemosensitizer that causes membrane destabilization and is an inhibitor of RND efflux pumps. The effects of NMP on biofilm formation and lipid metabolism in M. abscessus biofilms have not been investigated. Plumbagin (PLU) is an inhibitor of ABC efflux pumps that has not been studied for its effects on antibiotic tolerance in M. abscessus biofilms. In this study, we report that the efflux pump inhibitors NMP and PLU inhibit biofilm formation by 50% at sub-MIC levels. We show that NMP inhibits the incorporation of the radiolabeled long-chain fatty acid 14C-palmitate into glycopeptidolipids in cell surface lipids of log-phase M. abscessus. NMP also inhibits the utilization of the radiolabel in the biosynthesis of phosphatidylethanolamine in the cell surface and cellular lipids of M. abscessus cells in log-phase and in biofilms. Incorporation of the radiolabel into cardiolipin in the cellular lipids of M. abscessus biofilms was inhibited by NMP. The incorporation of 14C-acetate into cell surface phosphatidylethanolamine in log-phase and biofilm cells was also inhibited by NMP. Triacylglycerol biosynthesis using 14C-palmitate and 14C-acetate in cellular lipids of log-phase and biofilm cells was increased several folds by NMP. Efflux pump activity in M. abscessus cells was inhibited by 97% and 68% by NMP and PLU respectively. NMP and PLU caused 5-fold decreases in the minimum inhibitory concentrations of ciprofloxacin and clarithromycin against M. abscessus. Our results demonstrate that NMP and PLU affect important physiological processes in M. abscessus associated with its pathogenesis.}, }
@article {pmid39530700, year = {2024}, author = {Rieger, CD and Soliman, AM and Kaplia, K and Ghosh, N and Lopez, AC and Venkatesan, SA and Guevara Flores, AG and Filiol Belin, MA and Allen, F and Reynolds, M and McKenna, B and Lavallee, H and Weenie, A and Favel, T and Gendron, F and Ziffle, VE and El-Halfawy, OM}, title = {The antimicrobial potential of traditional remedies of Indigenous peoples from Canada against MRSA planktonic and biofilm bacteria in wound infection mimetic conditions.}, journal = {Microbiology spectrum}, volume = {12}, number = {12}, pages = {e0234124}, pmid = {39530700}, issn = {2165-0497}, abstract = {Methicillin-resistant Staphylococcus aureus (MRSA) is the leading cause of wound infections, often progressing into serious invasive bloodstream infections. MRSA disproportionately affects Indigenous peoples in Canada with higher rates of skin and wound infections, an example of persistent gaps in health outcomes between Indigenous and non-Indigenous peoples precipitated by the legacy of colonialism. Conversely, Indigenous peoples have long used natural remedies for infections and other diseases; however, their knowledge was rarely considered for modern medicine. The stagnant antibiotic discovery pipeline and alarming rise of resistance to current antibiotics prompted us to turn to Indigenous medicine as an untapped source of antimicrobials. As such, we collected and prepared 85 extracts of medicinal plants of value to Indigenous peoples spanning the Canadian Prairies. We explored the antimicrobial potential of these extracts against MRSA under wound infection-mimetic conditions compared with culture media typically used to study bacterial antibiotic responses and biofilms but not adequately representative of infection sites. We identified extracts with MRSA growth inhibitory [e.g., bergamot, dock, gaillardia, and dandelion extracts] and biofilm prevention and eradication [e.g., gumweed extracts] activities. Extracts, including those of chokecherry, hoary puccoon, and Northern bedstraw, were only active under wound infection-mimetic conditions, highlighting the benefit of antibiotic discovery under host-relevant conditions. Testing growth inhibitory extracts against an S. aureus cross-resistance platform suggested that they act through mechanisms likely distinct from known antibiotic classes. Together, through an interdisciplinary partnership leveraging Western approaches and traditional Indigenous knowledge, we identified plant extracts with promising antimicrobial potential for drug-resistant MRSA wound infections.IMPORTANCEWe explored the antimicrobial potential of traditional Indigenous remedies against MRSA under wound infection-mimetic conditions. We chose to tackle MRSA wound infections because they constitute an Indigenous health priority, ensuring mutual benefits and reciprocity, which are important principles in partnerships between Indigenous and non-Indigenous researchers. Our partnerships strive to serve as steps towards reconciliation with Indigenous peoples in Canada and a roadmap inspiring similar interdisciplinary collaborations to tackle other healthcare priorities. We identified extracts with promising antibacterial growth inhibitory, biofilm prevention, and eradication activities against MRSA. The antimicrobial potential of some extracts was only observed under wound infection-mimetic conditions, a proof-of-concept that screening under infection-mimetic conditions reveals novel activity undetected under standard conditions. The natural product antimicrobial extracts discovered herein warrant further investigation into their mode of action and chemical composition; they may address the dire need for new antimicrobial and anti-biofilm activity to counter the AMR crisis.}, }
@article {pmid39530158, year = {2024}, author = {Oliveira, VC and Soler-Comas, A and Rocha, ACSD and Silva-Lovato, CH and Watanabe, E and Torres, A and Fernández-Barat, L}, title = {The synergistic effect between phages and Ceftolozane/Tazobactam in Pseudomonas aeruginosa endotracheal tube biofilm.}, journal = {Emerging microbes &amp; infections}, volume = {13}, number = {1}, pages = {2420737}, pmid = {39530158}, issn = {2222-1751}, mesh = {*Biofilms/drug effects ; *Pseudomonas aeruginosa/virology/drug effects/physiology ; *Tazobactam/pharmacology ; *Cephalosporins/pharmacology ; *Anti-Bacterial Agents/pharmacology ; Humans ; *Pseudomonas Infections/microbiology/therapy ; Intubation, Intratracheal ; Microbial Sensitivity Tests ; Pseudomonas Phages/physiology ; Phage Therapy ; }, abstract = {Although an increased effectiveness has been suggested when phages and antibiotics are combined, this approach has not been tested against a mature biofilm on an endotracheal tube (ETT) surface. This study evaluated the effect of short- and long-term combined phage-antibiotic therapy in a control of a mature biofilm on an ETT surface. Pseudomonas aeruginosa strains, including susceptible and resistant clinical samples, were used to develop the ETT biofilm. Biofilm was treated with 10[8]PFU/mL of phage_2, phage_18 or 5 μg/mL of ceftolozane/tazobactam, alone or in combination with phages. The sequential combination of the two different phages and ceftolozane/tazobactam was also tested. Biofilm viability was assessed after short (2, 4, 24 h) and long-(48, 72 h) term treatment exposure using colony forming unit measurement. For long-term exposition, a new treatment shot was added every 24 h. In the sequential combination, the phage type was switched at 24 h of treatment. Regarding the susceptible strains, the treatments had limited antibiofilm effect after 2, 4 and 24 h. After 48 and 72 h, administering phages alone had no effect on biofilm viability, indicating the emergence of phage-resistant phenotypes. Nonetheless, the combined phage-antibiotic treatment reduced the biofilm viability in about 5-log, whilst antibiotic alone reduced in about 3-log. The sequential combination of phages and antibiotic reduced the biofilm viability in about 6-log. With respect to the resistant strains, no antibiofilm activity was observed regarding the treatment arms. The combination of phages and ceftolozane/tazobactam showed a synergism strain-dependent, being more apparent in susceptible strains.}, }
@article {pmid39529861, year = {2024}, author = {Utomo, RNC and Palkowitz, AL and Gan, L and Rudzinski, A and Franzen, J and Ballerstedt, H and Zimmermann, M and Blank, LM and Fischer, H and Wolfart, S and Tuna, T}, title = {In vitro plaque formation model to unravel biofilm formation dynamics on implant abutment surfaces.}, journal = {Journal of oral microbiology}, volume = {16}, number = {1}, pages = {2424227}, pmid = {39529861}, issn = {2000-2297}, abstract = {BACKGROUND: Biofilm formation on implant-abutment surfaces can cause inflammatory reactions. Ethical concerns often limit intraoral testing, necessitating preliminary in vitro or animal studies. Here, we propose an in vitro model using human saliva and hypothesize that this model has the potential to closely mimic the dynamics of biofilm formation on implant-abutment material surfaces in vivo.<br><br>METHODS: A saliva stock was mixed with modified Brain-Heart-Infusion medium to form biofilms on Titanium-Aluminum-Vanadium (Ti6Al4V) and Yttria-partially Stabilized Zirconia (Y-TZP) discs in 24-well plates. Biofilm analyses included crystal violet staining, intact cell quantification with BactoBox, 16S rRNA gene analysis, and short-chain fatty acids measurement. As a control, discs were worn in maxillary splints by four subjects for four days to induce in vivo biofilm formation.<br><br>RESULTS: After four days, biofilms fully covered Ti6Al4V and Y-TZP discs both in vivo and in vitro, with similar cell viability. There was a 60.31% overlap of genera between in vitro and in vivo biofilms in the early stages, and 41% in the late stages. Ten key oral bacteria, including Streptococcus, Haemophilus, Neisseria, Veillonella, and Porphyromonas, were still detectable in vitro, representing the common stages of oral biofilm formation.<br><br>CONCLUSION: This in vitro model effectively simulates oral conditions and provides valuable insights into biofilm dynamics.}, }
@article {pmid39528199, year = {2024}, author = {Faghani-Eskandarkolaei, P and Heli, H and Akbari, N and Koohi-Hosseinabadi, O and Sari Aslani, F and Sattarahmady, N}, title = {Antibacterial and anti-biofilm activities of gold-curcumin nanohybrids and its polydopamine form upon photo-sonotherapy of Staphylococcus aureus infected implants: In vitro and animal model studies.}, journal = {International journal of biological macromolecules}, volume = {282}, number = {Pt 6}, pages = {137430}, doi = {10.1016/j.ijbiomac.2024.137430}, pmid = {39528199}, issn = {1879-0003}, mesh = {*Staphylococcus aureus/drug effects ; *Gold/chemistry/pharmacology ; *Polymers/chemistry/pharmacology ; Animals ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Indoles/chemistry/pharmacology ; *Curcumin/pharmacology/chemistry ; *Biofilms/drug effects ; *Staphylococcal Infections/drug therapy ; Ultrasonic Therapy/methods ; Disease Models, Animal ; Microbial Sensitivity Tests ; }, abstract = {Implant-related infections are among the major post-surgery problems, and treatment of these infections is challenging due to the formation of biofilms by microorganisms such as Staphylococcus aureus. Herein, a novel gold-curcumin nanohybrid (GCNH) was synthesized for the first time and characterized. GCNH had a band gap energy of 2.41 eV, a zeta potential of -15 mV, and comprised uniform spherical particles with a mean diameter of 8 ± 2 nm. The biological macromolecule of polydopamine was then coated on GCNH to prepare a gold-curcumin-polydopamine nanohybrid (GCDNH). The nanohybrids were employed as novel dual photo-sonosensitizers for bacterial eradication by near-infrared (NIR) light and ultrasound (US) irradiations. GCNH and GCDNH represented photothermal conversion efficiencies of 26 and 32 %, respectively, and GCDNH represented a hemolysis rate of 2.3 % under both near-infrared (NIR) light and ultrasound (US) irradiations. NIR light and US irradiations (photo-sonotherapy) of Staphylococcus aureus using GCDNH depicted anti-bacterial and anti-biofilm efficiencies of 98 and 99 %, respectively, in synergistic manners, which are higher or as high as other sensitizers reported previously. The mechanism of photo-sonotherapy was related to generation of high levels of reactive oxygen species (ROS), and protein and nucleic acid leakages. In an in vivo infection model, NIR light and US irradiations annihilated Staphylococcus aureus on GCDNH-covered implants with high efficiency, without causing damage to normal tissues.}, }
@article {pmid39527987, year = {2025}, author = {Vadakkan, K and Jose, B and Mapranathukaran, VO and Sathishkumar, K and Ngangbam, AK and Rumjit, NP}, title = {Biofilm suppression of Pseudomonas aeruginosa by bio-engineered silver nanoparticles from Hellenia speciosa rhizome extract.}, journal = {Microbial pathogenesis}, volume = {198}, number = {}, pages = {107105}, doi = {10.1016/j.micpath.2024.107105}, pmid = {39527987}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Pseudomonas aeruginosa/drug effects ; *Silver/pharmacology/chemistry ; *Metal Nanoparticles/chemistry ; *Plant Extracts/pharmacology/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Rhizome/chemistry ; Microbial Sensitivity Tests ; Microscopy, Electron, Scanning ; Bacterial Adhesion/drug effects ; }, abstract = {Bacterial biofilm, a persistent issue in healthcare equipment and typical infections, is exacerbated by the pathogenesis and antibiotic tolerance of Pseudomonas aeruginosa. This bacterium remains a significant concern in the global healthcare sector. Silver nanoparticles, with their potent antibacterial properties, have emerged as a promising solution. This study, therefore, is of utmost importance as it aims to delve into the parameters influencing the biogenic nanoparticle-assisted regulation of bacterial adherence by Pseudomonas aeruginosa. The nano-sized particles were bioengineered using Hellenia speciosa rhizome extracts, which mainly included biologically active components such as mequinol, 4-hydroxy-3-methylacetophenone, and phenol, 2,6-dimethoxy, supplemented with the formation of silver nanostructured materials. The nanoclusters were characterized by UV-Vis spectrophotometry, X-ray scattering, and scanning electron microscopy (SEM). According to a microtiter plate experiment, the nanoparticle degraded biofilms up to 94.41 % at dosages varied from 0 to 25 μg/ml. The light microscopy study and the interface architecture of biofilm suppression by electron microscopy demonstrated the nano-sized particle's potential to prevent bacterial adherence.}, }
@article {pmid39526776, year = {2024}, author = {Dorison, L and Béchon, N and Martin-Gallausiaux, C and Chamorro-Rodriguez, S and Vitrenko, Y and Ouazahrou, R and Villa, R and Deschamps, J and Briandet, R and Gribaldo, S and Ghigo, J-M and Beloin, C}, title = {Identification of Veillonella parvula and Streptococcus gordonii adhesins mediating co-aggregation and its impact on physiology and mixed biofilm structure.}, journal = {mBio}, volume = {15}, number = {12}, pages = {e0217124}, pmid = {39526776}, issn = {2150-7511}, support = {ANR-10-LABX-62-IBEID).//Agence Nationale de la Recherche (ANR)/ ; //Minist&#xe8;re Fran&#xe7;ais de l'Education national, de l'enseignement supp&#xe9;rieur et de la recherche/ ; ANR-10-INBS-09-09//Agence Nationale de la Recherche (ANR)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Streptococcus gordonii/physiology/genetics/metabolism ; *Adhesins, Bacterial/metabolism/genetics ; *Veillonella/genetics/metabolism/physiology ; *Bacterial Adhesion ; *Actinomyces/physiology/genetics/metabolism ; Microbial Interactions ; Dental Plaque/microbiology ; Humans ; Type V Secretion Systems/metabolism/genetics ; Mouth/microbiology ; }, abstract = {UNLABELLED: The dental plaque is a polymicrobial community where biofilm formation and co-aggregation, the ability to bind to other bacteria, play a major role in the construction of an organized consortium. One of its prominent members is the anaerobic diderm Veillonella parvula, considered a bridging species, which growth depends on lactate produced by oral streptococci. Understanding how V. parvula co-aggregates and the impact of aggregation has long been hampered due to the lack of appropriate genetic tools. Here we studied co-aggregation of the naturally competent strain V. parvula SKV38 with various oral bacteria and its effect on cell physiology. We show that V. parvula requires different trimeric autotransporters of the type V secretion system to adhere to oral streptococci and actinomyces. In addition, we describe a novel adhesin of Streptococcus gordonii, VisA (SGO_2004), as the protein responsible for co-aggregation with V. parvula. Finally, we show that co-aggregation does not impact cell-cell communication, which is mainly driven by environmental sensing, but plays an important role in the architecture and species distribution within the biofilm.<br><br>IMPORTANCE: Our research explores the mechanisms of bacterial adhesion within the dental plaque, focusing on Veillonella parvula, a key player in the oral microbiome. Dependent on lactate from streptococci, V. parvula plays a crucial bridging role in the formation of dental biofilms by co-aggregating with other bacteria. Despite its importance, the understanding of the underlying mechanisms of co-aggregation remains limited. Our study shows that V. parvula uses different trimeric autotransporters to adhere to oral Streptococci and Actinomyces. We additionally identify a novel adhesin from S. gordonii, VisA (SGO_2004) facilitating this interaction. We found that although co-aggregation does not affect cell-cell communication, it is critical for biofilm structure and species distribution. This research opens up new avenues for exploring microbial interactions in dental health and diseases.}, }
@article {pmid39524554, year = {2024}, author = {Snell, AP and Manias, DA and Elbehery, RR and Dunny, GM and Willett, JLE}, title = {Arginine impacts aggregation, biofilm formation, and antibiotic susceptibility in Enterococcus faecalis.}, journal = {FEMS microbes}, volume = {5}, number = {}, pages = {xtae030}, pmid = {39524554}, issn = {2633-6685}, support = {R00 AI151080/AI/NIAID NIH HHS/United States ; }, abstract = {Enterococcus faecalis is a commensal bacterium in the gastrointestinal (GI) tract of humans and other organisms. E. faecalis also causes infections in root canals, wounds, the urinary tract, and on heart valves. E. faecalis metabolizes arginine through the arginine deiminase pathway, which converts arginine to ornithine and releases ATP, ammonia, and CO2. E. faecalis arginine metabolism also affects virulence of other pathogens during co-culture. E. faecalis may encounter elevated levels of arginine in the GI tract or the oral cavity, where arginine is used as a dental therapeutic. Little is known about how E. faecalis responds to growth in arginine in the absence of other bacteria. To address this, we used RNAseq and additional assays to measure growth, gene expression, and biofilm formation in E. faecalis OG1RF grown in arginine. We demonstrate that arginine decreases E. faecalis biofilm production and causes widespread differential expression of genes related to metabolism, quorum sensing, and polysaccharide synthesis. Growth in arginine also increases aggregation of E. faecalis and promotes decreased susceptibility to the antibiotics ampicillin and ceftriaxone. This work provides a platform for understanding how the presence of arginine in biological niches affects E. faecalis physiology and virulence of surrounding microbes.}, }
@article {pmid39521156, year = {2024}, author = {Delik, E and Eroğlu, B and Karabıyık, R and Tefon-Öztürk, BE}, title = {Antibiotic concentrations induce morphological changes and increase biofilm formation in multi-antibiotic and heavy metal resistant Kluyvera cryocrescens and Serratia fonticola.}, journal = {Microbial pathogenesis}, volume = {197}, number = {}, pages = {107112}, doi = {10.1016/j.micpath.2024.107112}, pmid = {39521156}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Serratia/drug effects/physiology/metabolism ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; *Kluyvera/drug effects/genetics ; *Drug Resistance, Multiple, Bacterial ; *Metals, Heavy/pharmacology ; Siderophores/pharmacology/metabolism ; Fresh Water/microbiology ; }, abstract = {Water pollution is the biggest challenge that has rendered existing water resources unusable due to contamination with antibiotics and heavy metals. Antibiotics are often used to treat bacterial diseases. Heavy metals, on the other hand, are micro-pollutants that pose a threat to aquatic systems, especially when they accumulate in nature. Increasing pollution and the uncontrolled use of antibiotics have exposed bacteria to non-lethal concentrations (sub-MIC), potentially leading to resistance. In this study, Kluyvera cryocrescens and Serratia fonticola were isolated from a freshwater source and characterised. The resistance profiles of the isolates to 16 antibiotics and 8 heavy metals were determined, revealing that they are multidrug-resistant. The effects of sub-MICs (MIC/2 and MIC/4) of antibiotics on biofilm formation, siderophore production, and cell morphology of bacteria were analysed. It was found that at some sub-MIC values of kanamycin, tetracycline, meropenem, erythromycin, and clarithromycin, biofilm formation by K. cryocrescens increased. An increase in biofilm production was also observed in S. fonticola at sub-MIC values of imipenem, meropenem, ceftazidime, ciprofloxacin, and clarithromycin. Moreover, significant morphological changes were observed in both isolates following treatment with meropenem, ciprofloxacin, and ceftazidime. After treatment with meropenem, the typical rod-shaped (bacillary) morphology of the isolates shifted to a round (coccoid) form. In contrast, the bacteria developed into long filaments after treatment with ciprofloxacin and ceftazidime. These changes in the bacteria may favour the development of resistance and pose challenges for the prevention and treatment of diseases. Therefore, it is crucial to understand how sub-MIC levels of antimicrobial agents alter the virulence properties of bacteria.}, }
@article {pmid39519322, year = {2024}, author = {Haj-Yahya, F and Steinberg, D and Sionov, RV}, title = {Trans, Trans-Farnesol Enhances the Anti-Bacterial and Anti-Biofilm Effect of Arachidonic Acid on the Cariogenic Bacteria Streptococcus mutans and Streptococcus sobrinus.}, journal = {International journal of molecular sciences}, volume = {25}, number = {21}, pages = {}, pmid = {39519322}, issn = {1422-0067}, mesh = {*Biofilms/drug effects ; *Streptococcus mutans/drug effects/physiology ; *Anti-Bacterial Agents/pharmacology ; *Arachidonic Acid/pharmacology/metabolism ; *Dental Caries/microbiology/prevention &amp; control ; *Streptococcus sobrinus/drug effects ; *Farnesol/pharmacology ; Microbial Sensitivity Tests ; Humans ; Drug Synergism ; Microbial Viability/drug effects ; }, abstract = {BACKGROUND: Streptococcus mutans and Streptococcus sobrinus are Gram-positive bacteria involved in the development of dental caries, as they are able to form biofilms on tooth enamel, ferment sugars into acids, and survive under acidic conditions. This ultimately leads to a local lowering of the pH value on the tooth surface, which causes enamel cavities.<br><br>HYPOTHESIS: One measure to reduce caries is to limit the growth of cariogenic bacteria by using two anti-bacterial agents with different mechanisms of action. The hypothesis of this study was that the anti-bacterial activity of &#x3c9;-6 polyunsaturated arachidonic acid (AA) against S. mutans and S. sobrinus can be enhanced by the sesquiterpene alcohol trans, trans-farnesol (t,t-farnesol).<br><br>METHODS: The anti-bacterial activity of single and combined treatment was determined by the checkerboard assay. Bacterial viability was assessed by live/dead SYTO 9/propidium iodide (PI) staining on flow cytometry. Anti-biofilm activity was determined by MTT metabolic assay, crystal violet staining of biofilm biomass, SYTO 9/PI staining by spinning disk confocal microscopy (SDCM) and high-resolution scanning electron microscopy (HR-SEM).<br><br>RESULTS: t,t-Farnesol lowered the minimum inhibitory concentration (MIC) and the minimum biofilm inhibitory concentration (MBIC) of AA at sub-MICs. AA reduced the metabolic activity of preformed mature biofilms, while t,t-farnesol had no significant effect. The enhanced anti-bacterial effect of the combined t,t-farnesol/AA treatment was further evidenced by increased PI uptake, indicating membrane perforation. The enhanced anti-biofilm effect was further verified by SDCM and HR-SEM. Gene expression studies showed reduced expression of some biofilm-related genes.<br><br>CONCLUSIONS: Altogether, our study suggests a potential use of the two naturally occurring compounds arachidonic acid and t,t-farnesol for preventing biofilm formation by the cariogenic bacteria S. mutans and S. sobrinus. These findings have implications for caries prevention.}, }
@article {pmid39519236, year = {2024}, author = {Krzyżek, P}, title = {What Is a Biofilm? Lessons Learned from Interactions with Immune Cells.}, journal = {International journal of molecular sciences}, volume = {25}, number = {21}, pages = {}, pmid = {39519236}, issn = {1422-0067}, mesh = {*Biofilms/growth &amp; development ; Humans ; Animals ; Host-Pathogen Interactions/immunology ; }, abstract = {Biofilms are unique, multicellular life forms that challenge our understanding of the microbial functioning. The last decades of research on biofilms have allowed us to better understand their importance in the context of both health and various pathologies in the human body, although many knowledge gaps hindering their correct comprehension still exist. Biofilms are classically described as mushroom-shaped structures attached to the substrate; however, an increasing body of evidence shows that their morphology in clinical conditions may differ significantly from that classically presented. Although this may result partly from the unique physicochemical conditions within the host, the interaction between microbes and immune cells during development of a biofilm should not be underestimated. The current Opinion confronts the classical view on biofilms with the latest scientific research describing the vitality of interactions with immune cells as a modulator of the biofilm phenotype and behavior in clinical conditions.}, }
@article {pmid39519227, year = {2024}, author = {Schoberleitner, I and Lackner, M and Coraça-Huber, DC and Augustin, A and Imsirovic, A and Sigl, S and Wolfram, D}, title = {SMI-Capsular Fibrosis and Biofilm Dynamics: Molecular Mechanisms, Clinical Implications, and Antimicrobial Approaches.}, journal = {International journal of molecular sciences}, volume = {25}, number = {21}, pages = {}, pmid = {39519227}, issn = {1422-0067}, support = {D152500-015-015//Establishment Labs, Costa Rica/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; Humans ; *Fibrosis ; *Breast Implants/adverse effects ; Female ; Anti-Infective Agents/pharmacology/therapeutic use ; Foreign-Body Reaction ; Anti-Bacterial Agents/pharmacology/therapeutic use ; Animals ; }, abstract = {Silicone mammary implants (SMIs) frequently result in capsular fibrosis, which is marked by the overproduction of fibrous tissue surrounding the implant. This review provides a detailed examination of the molecular and immunological mechanisms driving capsular fibrosis, focusing on the role of foreign body responses (FBRs) and microbial biofilm formation. We investigate how microbial adhesion to implant surfaces and biofilm development contribute to persistent inflammation and fibrotic responses. The review critically evaluates antimicrobial strategies, including preoperative antiseptic protocols and antimicrobial-impregnated materials, designed to mitigate infection and biofilm-related complications. Additionally, advancements in material science, such as surface modifications and antibiotic-impregnated meshes, are discussed for their potential to reduce capsular fibrosis and prevent contracture of the capsule. By integrating molecular insights with clinical applications, this review aims to elucidate the current understanding of SMI-related fibrotic responses and highlight knowledge gaps. The synthesis of these findings aims to guide future research directions of improved antimicrobial interventions and implant materials, ultimately advancing the management of capsular fibrosis and enhancing patient outcomes.}, }
@article {pmid39518602, year = {2024}, author = {Aqabat, HMA and Abouelseoud, M and Rafaat, SN and Shamel, M and Schäfer, E and Souza, EM and Saber, S}, title = {Cytocompatibility, Antibacterial, and Anti-Biofilm Efficacy of Grape Seed Extract and Quercetin Hydrogels Against a Mature Endodontic Biofilm Ex Vivo Model.}, journal = {Journal of clinical medicine}, volume = {13}, number = {21}, pages = {}, pmid = {39518602}, issn = {2077-0383}, abstract = {Background/Objectives: To assess the cytocompatibility, antibacterial and anti-biofilm efficacy of grape seed extract (GSE) and quercetin hydrogels versus calcium hydroxide (CH) as intracanal medications (ICMs) against an endodontic ex vivo biofilm model. Methods: Single-rooted teeth (n = 50) were prepared and sterilized before being infected with E. faecalis to develop a mature biofilm. They were divided into five equal groups according to the ICM used: G1: medicated with CH paste, G2: medicated with GSE hydrogel, G3: medicated with quercetin hydrogel, G4: positive control group that was infected and not medicated, and G5: negative control group that was neither infected nor medicated. After 1 week, the ICM was removed, and the root canals were cultured to assess the antibacterial efficacy by counting the colony-forming units and the anti-biofilm efficacy by the crystal violet assay. Dead/live bacterial viability was assessed by CFLSM examination, while the cytocompatibility was assessed using the MTT assay. Results: CH had the best antibacterial efficacy, followed by GSE and quercetin hydrogels (p < 0.001). Regarding the anti-biofilm efficacy, GSE was superior, followed by quercetin and CH (p < 0.001). CFLSM examination showed CH and GSE hydrogel to be highly effective in comparison to the positive control (p < 0.0001), with no statistical difference between them (p > 0.05). CH showed significantly higher cell viability percentages using a 500 μg/mL, while quercetin and GSE started to show cell viability > 70% at concentrations of 125 μg/mL and 62.5 μg/mL. Conclusions: CH fulfilled the ideal requirements of ICM as being both antibacterial and non-cytotoxic compared to the other materials tested.}, }
@article {pmid39517145, year = {2024}, author = {Ma, X and Ma, J and Liu, J and Hao, H and Hou, H and Zhang, G}, title = {Inhibitory Effect of Phenethyl Isothiocyanate on the Adhesion and Biofilm Formation of Staphylococcus aureus and Application on Beef.}, journal = {Foods (Basel, Switzerland)}, volume = {13}, number = {21}, pages = {}, pmid = {39517145}, issn = {2304-8158}, support = {2022YFD210050103//The National Key Research and Development Program of China/ ; }, abstract = {This study aimed to explore the mechanism by which phenethyl isothiocyanate (PEITC) inhibited the adhesion and biofilm formation of Staphylococcus aureus (S. aureus). PEITC exhibited antimicrobial efficacy against S. aureus, demonstrating a minimum inhibition concentration (MIC) of 1 mmol/L. PEITC exerted its antibacterial effect by disrupting cell membrane integrity, and it decreased total adenosine triphosphate (ATP) production after 1 and 4 h treatment. PEITC at 0.5 mmol/L increased the level of intracellular reactive oxygen species (ROS) by 26.39% compared to control. The mature biofilm of S. aureus was destroyed by 86.4% after treatment with PEITC for 24 h. Adhesion tests revealed that PEITC at 0.5 mmol/L reduced 44.51% of the S. aureus that adhered to NCM460 cells. Furthermore, at the genetic level, PEITC significantly downregulated the related genes by 31.26% to 97.04%, including agrB, agrD, isdA, ebh, luxS, fnbA, and icaR. Moreover, PEITC markedly inhibited S. aureus proliferation in beef preserved at temperatures of 25 and 4 °C, respectively. In summary, the present study suggests that PEITC effectively inhibits the adhesion and biofilm formation of S. aureus by affecting the relevant genes of S. aureus and holds promise for microbial management in meat products.}, }
@article {pmid39516577, year = {2024}, author = {Radmand, F and Baseri, M and Memar, MY and Ebrahimi, A and Hamishehkar, H and Asnaashari, S and Naseri, A and Kouhsoltani, M}, title = {Anti-biofilm and anti-glucosyltransferase effects of nano liposomal plant extracts against Streptococcus mutans.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {27304}, pmid = {39516577}, issn = {2045-2322}, support = {64554//Tabriz University of Medical Sciences/ ; }, mesh = {*Biofilms/drug effects ; *Streptococcus mutans/drug effects ; *Plant Extracts/pharmacology/chemistry ; *Glucosyltransferases/antagonists &amp; inhibitors/metabolism ; *Liposomes ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; Dental Caries/microbiology/prevention &amp; control ; Nanoparticles/chemistry ; Humans ; }, abstract = {The role of Streptococcus mutans in the initiation of caries is related to its acidogenicity, aciduricity, and polysaccharides extracellular layer production by glucosyltransferases in dental biofilms. Therefore, inhibition of glucosyltransferase activity impairs the virulence of cariogenic biofilms, which can be used to prevent dental caries. We evaluated the anti-bacterial, anti-biofilm, and anti-glucosyltransferases effects of nanoliposomal herbal aqueous extracts of Liquorice (Glycyrrhiza glabra; G. glabra), Ginger (Zingiber officinale; Z. officinale), Pomegranate (Punica granatum; P. granatum), and Rose (Rosa damascene; R. damascene) via minimum bactericidal concentration and minimum inhibitory concentration against Streptococcus mutans strain ATCC 35,668. An anti-biofilm assay was performed using a minimum biofilm inhibitory concentration test. Among herbs, only P. granatum showed an antibacterial effect. Therefore, a nanoliposomal formulation of P. granatum was developed and characterized. Its effect on S.mutans glucosyltransferases was assessed by measuring glucan amount. The nanoliposomal formulation of P.granatum showed a significantly higher anti-biofilm effect than P. granatum aqueous extract. Their similar potential in blocking glucosyltransferases showed that the nanoliposomal formulation of P.granatum blocked other pathways rather than blocking glucosyltransferases for its anti-biofilm effect. Collectively, the nanoliposomal formulation of P.granatum, due to its anti- Streptococcus mutans characteristics, would be a production which open a new horizon for the oral pharmaceutical industry.}, }
@article {pmid39515706, year = {2024}, author = {Yu, Y and Dong, Q and Wang, J and Hu, Y and Liu, Z and Chen, Q}, title = {Chitosan oligosaccharide efficiently inhibits Cronobacter sakazakii biofilm by interacting with out membrane protein A for regulating CpxRA-mediated cellulose production pathway.}, journal = {International journal of biological macromolecules}, volume = {282}, number = {Pt 6}, pages = {137302}, doi = {10.1016/j.ijbiomac.2024.137302}, pmid = {39515706}, issn = {1879-0003}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Cronobacter sakazakii/drug effects/metabolism ; *Cellulose/biosynthesis ; *Chitosan/pharmacology/chemistry ; *Bacterial Outer Membrane Proteins/metabolism/genetics ; *Bacterial Proteins/metabolism/genetics ; *Oligosaccharides/pharmacology/chemistry ; Gene Expression Regulation, Bacterial/drug effects ; Cyclic GMP/metabolism/analogs &amp; derivatives ; Anti-Bacterial Agents/pharmacology/chemistry ; }, abstract = {Chitosan oligosaccharide (COS) can efficiently inhibit Cronobacter sakazakii (C. sakazakii) biofilm independent on antibacterial activity. However, the mechanism is still unclear. In this study, the role of out membrane protein A (OmpA) and its downstream CpxRA-mediated cellulose production pathway in COS's inhibition on C. sakazakii biofilm were explored. The spectroscopic results were shown that COS could interact with OmpA, and this changed OmpA's second structure and spatial conformation as well as cell membrane permeability and COS uptake. C. sakazakii ΔOmpA strain under COS treatment had a lower cell membrane permeability and COS uptake rate. The interaction between OmpA and COS could further initiate CpxRA system. The regulon cpxP expression level was therefore up-regulated. The deletion of the response regulator cpxR gene reduced inhibitory effect of COS on biofilm. CpxRA system inhibited expression of csgD and adrA, which coded diguanylate cyclase to generate cyclic diguanosine monophosphate (c-di-GMP). The expression of bcsAB was then down-regulated by c-di-GMP, and the cellulose production as well as biofilm were reduced. The addition of exogenous c-di-GMP could mitigate the inhibition of COS on C. sakazakii biofilm. These results not only help to elucidate biofilm inhibition mechanism of COS, but also provided a basis for developing anti-biofilm agents targeted OmpA.}, }
@article {pmid39515546, year = {2025}, author = {Lock, GA and Helfer, VE and Dias, BB and Barreto, F and Dalla Costa, T and de Araújo, BV}, title = {Can distinct Gram-negative biofilm-forming bacteria have different impacts on ciprofloxacin lung penetration?.}, journal = {Microbial pathogenesis}, volume = {198}, number = {}, pages = {107092}, doi = {10.1016/j.micpath.2024.107092}, pmid = {39515546}, issn = {1096-1208}, mesh = {*Ciprofloxacin/pharmacokinetics/pharmacology/administration &amp; dosage ; Animals ; *Klebsiella pneumoniae/drug effects ; *Biofilms/drug effects/growth &amp; development ; *Lung/microbiology ; Rats ; *Pseudomonas aeruginosa/drug effects ; *Anti-Bacterial Agents/pharmacokinetics/pharmacology/administration &amp; dosage ; *Microbial Sensitivity Tests ; *Klebsiella Infections/microbiology/drug therapy ; Disease Models, Animal ; Male ; Pseudomonas Infections/microbiology/drug therapy ; Gram-Negative Bacteria/drug effects ; Rats, Sprague-Dawley ; }, abstract = {Literature have shown that Gram-negative bacteria release endotoxins which alter drug membrane transporters and could potentially influence antimicrobials distribution to the infection site depending on the infecting bacteria. Previously, a population pharmacokinetic (popPK) model describing ciprofloxacin (CIP) concentrations in healthy, and Pseudomonas aeruginosa pneumonic rats showed that the chronic stage of the infection significantly reduced the drug lung penetration. In this study, CIP lung penetration in Klebsiella pneumoniae chronically (14 d) infected rats following CIP 20 mg/kg i.v. bolus dosing was investigated and the popPK model developed previously was used to evaluate CIP lung exposure. Drug plasma exposure was similar for both bacteria and higher than observed in healthy animals. Probability of target attainment analysis using plasma data following current dosing regimen (20 mg q8h equivalent to 400 mg q8h in humans) showed that CIP PK/PD index (ƒAUC0-24/MIC ≥90) is achieved for the most prevalent MIC's of both bacteria. However, CIP free lung concentrations were reduced in infected animals by 46.8 % (P. aeruginosa) and 68.4 % (K. pneumoniae) in comparison to healthy animals. The higher lung clearance observed (0.306 L/h/kg) in K. pneumoniae infected animals lead to a lower free CIP lung exposure in comparison to the P. aeruginosa group (0.105 L/h/kg). In summary, although plasma PK/PD index is achieved by the current regimen, chronic pneumonia by biofilm-forming bacteria decreases lung exposure to CIP and this decrease is dependent on the infecting bacteria. The clinical relevance of this finding needs to be determined.}, }
@article {pmid39515532, year = {2024}, author = {Zhao, YF and Lai, CY and Zhao, HP}, title = {Innovative nitrogen transformation: Coexistence of DNRA and denitrification under high alkalinity in a hydrogen-based membrane biofilm reactor.}, journal = {Chemosphere}, volume = {368}, number = {}, pages = {143705}, doi = {10.1016/j.chemosphere.2024.143705}, pmid = {39515532}, issn = {1879-1298}, mesh = {*Biofilms ; *Denitrification ; *Bioreactors/microbiology ; *Nitrates/metabolism ; *Hydrogen/metabolism ; *Nitrogen/metabolism ; Wastewater/chemistry ; Hydrogen-Ion Concentration ; Waste Disposal, Fluid/methods ; Ammonium Compounds/metabolism ; Water Pollutants, Chemical/metabolism ; Nitrites/metabolism ; }, abstract = {Nitrate (NO3[-]) contamination has become a significant global environmental issue. Traditional nitrate reduction processes typically require external pH control to maintain neutral conditions and prevent nitrite accumulation. In this study, a hydrogen-based membrane biofilm reactor (H2-MBfR) was constructed without external pH regulation. The reactor relied on the alkalinity generated by the nitrate reduction process itself, maintaining a highly alkaline environment with stable denitrification and up to 60% ammonium conversion at pH levels reaching 11.70. The DNRA process was found to be independent of substrate type, inversely proportional to electron supply, and exhibited the highest reaction rate at pH 11, as confirmed by both ex-situ and in-situ batch experiments. Microbial community analysis indicated that Meiothermus was the predominant genus within the biofilm. This research reveals a novel nitrogen transformation phenomenon, demonstrating the coexistence of DNRA and denitrification processes under high alkalinity conditions in the H2-MBfR system. These findings offer new insights into nitrate reduction processes and suggest potential advancements in wastewater treatment and resource recovery.}, }
@article {pmid39513945, year = {2024}, author = {Hu, H and Xu, J and Chen, J and Tang, C and Zhou, T and Wang, J and Kang, Z}, title = {Influence of Flagella on Salmonella Enteritidis Sedimentation, Biofilm Formation, Disinfectant Resistance, and Interspecies Interactions.}, journal = {Foodborne pathogens and disease}, volume = {}, number = {}, pages = {}, doi = {10.1089/fpd.2024.0088}, pmid = {39513945}, issn = {1556-7125}, abstract = {Flagella are essential for bacterial motility and biofilm formation by aiding bacterial attachment to surfaces. However, the impact of flagella on bacterial behavior, particularly biofilm formation, remains unclear. This study constructed two flagellar mutation strains of Salmonella Enteritidis (SE), namely, SE-ΔflhD and SE-ΔflgE, and confirmed the loss of flagellar structures and motility in these strains. The mutant strains exhibited growth comparable with the wild-type (WT) strain but had higher sedimentation rates. Biofilm biomass did not differ significantly between the WT and mutant strains, except for SE-ΔflgE at 3 d. SE-ΔflgE showed increased susceptibility to sodium hypochlorite compared to the WT. The co-sedimentation rate of flagella-deficient strains was lower than the WT, and the biomass of dual-species biofilm formed by Bacillus paramycoides B5 with SE-ΔflhD or SE-ΔflgE was significantly lower than with the WT. These findings emphasize the significance of SE flagella in biofilm formation and interspecies interactions, offering insights into targeted biofilm prevention and control measures.}, }
@article {pmid39512827, year = {2024}, author = {Farhadi, K and Rajabi, E and Varpaei, HA and Iranzadasl, M and Khodaparast, S and Salehi, M}, title = {Thymol and carvacrol against Klebsiella: anti-bacterial, anti-biofilm, and synergistic activities-a systematic review.}, journal = {Frontiers in pharmacology}, volume = {15}, number = {}, pages = {1487083}, pmid = {39512827}, issn = {1663-9812}, abstract = {INTRODUCTION: Klebsiella poses a significant global threat due to its high antibiotic resistance rate. In recent years, researchers have been seeking alternative antimicrobial agents, leading to the introduction of natural compounds such as monoterpenes, specifically thymol and carvacrol. This review aims to illustrate the potential antimicrobial, anti-biofilm, and synergistic traits of thymol and carvacrol in combat against Klebsiella.<br><br>METHODS: Searching PubMed, Scopus, and Web of Science, we reviewed available evidence on the antibacterial effects of thymol, carvacrol, or combined with other compounds against Klebsiella until May 2024. Reference checking was performed after the inclusion of studies. Minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), fractional inhibitory concentration (FIC), and anti-biofilm activity were gathered, and the MBC/MIC ratio was calculated to assess the bactericidal efficacy.<br><br>RESULTS: We retrieved 38 articles out of 2,652 studies screened. The gathered data assessed the anti-microbial activity of thymol, carvacrol, and both compounds in 17, 10, and 11 studies, respectively. The mean (&#xb1; standard deviation) non-weighted MIC was 475.46&#xa0;&#x3bc;g/mL (&#xb1;509.95) out of 60 MIC for thymol and 279.26&#xa0;&#x3bc;g/mL (&#xb1;434.38) out of 68 MIC for carvacrol. Thymol and carvacrol showed anti-biofilm activities in the forms of disruption, inhibition, and mass reduction of biofilms. The MBC/MIC ratio was lower than 4 in 45 out of 47 cases, showing high bactericidal efficacy. FIC values were gathered for 68 combinations of thymol and carvacrol with other compounds, and they were mostly synergistic or additive.<br><br>CONCLUSION: Thymol and carvacrol alone or in combination with other compounds, specifically known antibiotics, show great antimicrobial activity.}, }
@article {pmid39512295, year = {2024}, author = {Goel, A and Swami, V and Patil, AS and Swami, VV}, title = {Preventive Effect of Ultraviolet Photofunctionalization on Peri-implant Biofilm Formation: An In vivo Randomized Study.}, journal = {Contemporary clinical dentistry}, volume = {15}, number = {3}, pages = {192-197}, pmid = {39512295}, issn = {0976-237X}, abstract = {BACKGROUND: Peri-implant biofilm formation due to local bacterial colonization is one of the important factors for the instability of temporary anchorage devices (TADs).<br><br>AIM: The aim of this study was to quantify and compare the colonization of Streptococcus sanguinis on ultraviolet (UV) treated and untreated titanium TADs.<br><br>MATERIALS AND METHODS: This prospective, in vivo study included 20 subjects requiring orthodontic treatment with first premolar extraction, followed by retraction of the anterior teeth with absolute anchorage using TADs. TADs were placed interdentally, in the keratinized tissue between the upper second premolar and the first molar on the buccal side, at the mucogingival junction. It was a split-mouth study where one side of TAD was UV-treated for 15 min, and the other side was kept untreated as a control. TADs were removed after 6 months for S. sanguinis quantification on both sides and were compared for biofilm reduction.<br><br>STATISTICAL ANALYSIS: Statistical software was used to perform unpaired t-tests for the individual samples as well as for comparing total UV-treated and untreated samples. P <0.05 was considered significant.<br><br>RESULTS: The mean bacterial count (per ml) was found to be 2.2 &#xd7; 10[6] copy numbers and 8.9 &#xd7; 10[6] copy numbers in the UV group and untreated group, respectively. The total count of bacteria was found to be less in the UV-treated group compared to the untreated group.<br><br>CONCLUSIONS: The study concludes that UV photofunctionalization results in a significant reduction of S. sanguinis colony on TADs with reduced chances of failure due to inflammation.}, }
@article {pmid39511037, year = {2024}, author = {Özdemir, C and Erdoğan, &#x130; and Özdemir, K and Akçelik, N and Akçelik, M}, title = {Comparative analysis of biofilm structures in Salmonella Typhimurium DMC4 strain and its dam and seqA gene mutants using Fourier transform infrared spectroscopy (FT-IR) and Raman spectroscopy methods.}, journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]}, volume = {}, number = {}, pages = {}, pmid = {39511037}, issn = {1678-4405}, abstract = {It is well-established that the dam and seqA genes act in the biofilm production in Salmonella. However, the molecular basis underlying this activity remains unexplored. This study aims to address this gap in the literature. In this study, comparative Fourier Transform Infrared (FT-IR) Spectroscopy and Raman spectral analyses were conducted to investigate the molecular basis of decreases in swimming, swarming motility, and biofilm characteristics observed in the dam and seqA gene mutants of S. Typhimurium DMC4 wild-type strain. The comparative analysis revealed a pronounced reduction in proteins, lipids, carbohydrates, and nucleic acids within the biofilm structures of mutant strains. These findings confirm that these macromolecules are crucial for the integrity and functionality of biofilm structures. FT-IR analysis showed that while amide-I bands decreased in the biofilm structures of mutant strains, amide-II bands increased compared to the wild-type strain. Similarly, Raman analyses indicated an increase in amide-IV bonds and a decrease in amide-V bonds. The parallelism between FT-IR and Raman spectral analysis results, particularly regarding amide I, amide V, amide II, and amide IV bands, is noteworthy. Additionally, these findings may lead to the development of markers for rapidly diagnosing transitions from planktonic to biofilm form in Salmonella. The substantial decrease in β-glucans and lipids, including cellulose, within the biofilm matrix of mutant strains highlights the critical role these polymers play in swimming and swarming motility. Given the clinical and industrial importance of Salmonella biofilms, it is crucial to develop strategies to prevent biofilm formation and identify target molecules that can inhibit biofilm formation. The results of our study suggest that β-glucans and amides are essential targets in the effort to combat Salmonella biofilms.}, }
@article {pmid39510522, year = {2024}, author = {Mensi, M and Sordillo, A and Marchetti, S and Calza, S and Scotti, E}, title = {Clinical Comparison of Guided Biofilm Therapy and Scaling and Root Planing in the Active Phase of Periodontitis Management.}, journal = {European journal of dentistry}, volume = {}, number = {}, pages = {}, doi = {10.1055/s-0044-1791221}, pmid = {39510522}, issn = {1305-7456}, abstract = {OBJECTIVE: The aim of this randomized, controlled, split-mouth study was to compare full-mouth air polishing followed by ultrasonic debridement (known as Guided Biofilm Therapy [GBT]) versus traditional Scaling and Root Planing (SRP), in terms of pocket closure in patients with stages III and IV periodontitis.<br><br>MATERIALS AND METHODS: &#x2003;The patients underwent periodontal therapy in two sessions. At the beginning of the first session, quadrants I and IV and II and III were randomly assigned to GBT or SRP treatment. Periodontal parameters were collected at baseline, 6 weeks (T1), and 3 months (T2) after therapy. The primary outcome was the number of experimental sites (pocket probing depth [PPD] >4 and <10&#x2009;mm) becoming closed pockets (PPD &#x2264; 4&#x2009;mm bleeding on probing [BOP] negative) at T1 and T2. Secondary outcomes were PPD, recession, clinical attachment level, BOP, and plaque index variations at the experimental sites and treatment time.<br><br>STATISTICAL ANALYSIS: &#x2003;A 10% difference in the primary outcome between the two protocols was set as the threshold to define inferiority/noninferiority of the test treatment. The primary outcome was modeled using a generalized estimating equation model to account for intrapatient measurement correlation. The estimates are reported as differences between groups' percentages (treatments or time points) and corresponding 95% confidence interval (95% CI). All analyses assumed a significance level of 5%.<br><br>RESULTS: &#x2003;A total of 32 patients were selected. Mean PPD (mm) reduced from 6.23 (6.06-6.40) to 3.33 (3.06-3.61) at T2 for GBT, and from 6.21 (6.04-6.38) to 3.32 (3.11-3.53) at T2 for SRP. Both treatments reached a comparable percentage of closed pockets at T1 (77.9% for GBT vs. 80.1% for SRP, p&#x2009;=&#x2009;0.235) and T2 (84.1% for GBT vs. 84.4% for SRP, p&#x2009;=&#x2009;0.878), with no statistically or clinically significant difference. GBT and traditional SRP with ultrasonic and hand instruments reach satisfactory clinical results in the active treatment of patients with stages III and IV periodontitis, with comparable rates of closed pockets and treatment time.<br><br>CONCLUSION: &#x2003;GBT is a suitable option in the active phase of periodontitis management in patients with stages III and IV periodontitis.}, }
@article {pmid39510503, year = {2024}, author = {Brown, SRB and Gensler, CA and Sun, L and D'Amico, DJ}, title = {Evaluating the Efficacy of Ɛ-poly-lysine, Hydrogen Peroxide, and Lauric Arginate to Inhibit Listeria monocytogenes Biofilm Formation and Inactivate Mature Biofilms.}, journal = {Journal of food protection}, volume = {87}, number = {12}, pages = {100399}, doi = {10.1016/j.jfp.2024.100399}, pmid = {39510503}, issn = {1944-9097}, mesh = {*Biofilms/drug effects ; *Listeria monocytogenes/drug effects ; *Hydrogen Peroxide/pharmacology ; *Polylysine/pharmacology ; Microbial Sensitivity Tests ; Food Microbiology ; Arginine/pharmacology/analogs &amp; derivatives ; Anti-Bacterial Agents/pharmacology ; Colony Count, Microbial ; Humans ; }, abstract = {Preventing the introduction of Listeria monocytogenes, subsequent biofilm formation, and persistence in food processing environments is important for reducing the risk of cross-contamination of ready-to-eat foods. This study determined the effect of Ɛ-poly-lysine (EPL), hydrogen peroxide (HP), and lauric arginate (LAE) on L. monocytogenes biofilm formation and the inactivation of mature biofilms. For inhibition studies, biofilms of L. monocytogenes Scott A (serotype 4b) and 2014L-6025 (serotype 1/2b) were developed separately at 37 °C for 48 h in the presence of sub-inhibitory concentrations (SIC) of either EPL (10 ppm), HP (2 ppm), or LAE (1.5 ppm) on polystyrene plates and stainless-steel rounds. Inactivation was determined by exposing mature biofilms on each surface to each antimicrobial at their minimum bactericidal concentration (MBC), 10xMBC, or 100xMBC for 24 h at 37 °C. The presence of these antimicrobials at SIC did not inhibit biofilm formation on either surface and their effect on mature biofilms varied by strain and surface. Application of EPL at 1xMBC (100 ppm) for 24 h resulted in greater reductions in counts of both strains on polystyrene than HP (40 ppm) and LAE (5 ppm) under the same conditions at 1xMBC (P ≤ 0.0243). Exposure of mature biofilms to LAE at 10xMBC (50 ppm) for 1 h was more effective in reducing counts on polystyrene than HP at 10xMBC (400 ppm) for the same duration (P ≤ 0.0136), and both HP and LAE applied at 100xMBC (4,000 and 500 ppm, respectively) for 24 h more effectively inactivated mature biofilms of L. monocytogenes Scott A on polystyrene compared to EPL (10,000 ppm) (P ≤ 0.0307). Application of LAE at 10xMBC for 24 h was more effective at inactivating strain Scott A on stainless steel compared to 10xMBC of EPL (1,000 ppm) or HP (P ≤ 0.0430). Future studies are needed to determine the efficacy of these and other antimicrobials on additional strains and serotypes of L. monocytogenes at temperatures relevant to food production and storage.}, }
@article {pmid39510286, year = {2024}, author = {Izma, G and Ijzerman, MM and McIsaac, D and Raby, M and Prosser, RS and Rooney, RC}, title = {Dietary exposure of stormwater contaminants in biofilm to two freshwater macroinvertebrates.}, journal = {The Science of the total environment}, volume = {957}, number = {}, pages = {177390}, doi = {10.1016/j.scitotenv.2024.177390}, pmid = {39510286}, issn = {1879-1026}, mesh = {Animals ; *Biofilms ; *Water Pollutants, Chemical/analysis ; *Dietary Exposure/statistics &amp; numerical data ; Ontario ; Pesticides/analysis ; Environmental Monitoring ; Food Chain ; Snails/physiology ; Fresh Water ; Ephemeroptera/physiology ; Ponds ; }, abstract = {Aquatic habitats in urban environments are exposed to complex contaminant mixtures that may harm aquatic biota. The impact of contaminant transfer from contaminated biofilm through aquatic food webs is still understudied, as is the current state of knowledge on dietary exposure of urban contaminants to biota residing in stormwater ponds. Our overall objective was to characterize urban pesticide accumulation in a common aquatic food source (biofilm) in stormwater ponds and to investigate the potential toxicity of that food source by testing the responses of two freshwater macroinvertebrates to experimental exposure. We conducted two dietary bioassays using biofilm collected from 15 stormwater ponds in Brampton, Ontario: an acute exposure with the mayfly Neocloeon triangulifer, and a chronic exposure with the freshwater snail Planorbella pilsbryi. We screened for 542 current-use and legacy pesticides to measure pesticide burden (the number of pesticides detected) and the concentration of pesticides in the biofilm. We also quantified chlorophyll-a, pheophytin, and ash-free dry weight content which we used as indicators of biofilm quality. We found no correlations between pesticide burden and chlorophyll-a, pheophytin, or ash-free dry weight of the biofilm diets. Compared to control diets, biofilms collected from stormwater ponds caused a reduction in survival and growth endpoints for both test species, indicating that biofilm-consuming invertebrates living in stormwater ponds may be experiencing risks previously unaccounted for by traditional ecological risk assessments. Pesticide occurrences in biofilm diets did not relate to mayfly survival, growth, or biomass production. Nor were they related to snail growth. This suggests that other contaminants in stormwater-cultivated biofilm are contributing to the observed effects. Snail survival and biomass production were negatively related to pesticide burden in the diets. This implies that duration of exposure may influence the degree and manifestation of pesticide toxicity via dietary exposure.}, }
@article {pmid39508342, year = {2025}, author = {Miranda, ML and Salomão, KB and Botazzo Delbem, AC and Danelon, M and Oliveira Barbosa, ER and Sampaio, C and Campos, LA and Brighenti, FL}, title = {Arginine combination with fluoride and calcium glycerophosphate: effects of concentration and on biofilm fluid.}, journal = {Future microbiology}, volume = {20}, number = {3}, pages = {201-212}, pmid = {39508342}, issn = {1746-0921}, support = {313473/2019-6//Conselho Nacional de Desenvolvimento Cient&#xed;fico e Tecnol&#xf3;gico/ ; 001//Coordena&#xe7;&#xe3;o de Aperfei&#xe7;oamento de Pessoal de N&#xed;vel Superior/ ; 2019/08375-0 and 2020/16330-3//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado de S&#xe3;o Paulo/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Arginine/pharmacology/metabolism ; *Fluorides/pharmacology ; *Glycerophosphates/pharmacology ; *Microbial Viability/drug effects ; Bacteria/drug effects/metabolism ; Phosphorus/pharmacology/metabolism ; Calcium/metabolism/pharmacology ; }, abstract = {Aim: To study the influence of varying concentrations of arginine (Arg) combined with fluoride (F) and/or calcium glycerophosphate (CaGP) on biofilms.Materials &amp; methods: Biofilms were analyzed for acidogenicity, microbial viability and Ca, F and inorganic phosphorus (P) concentrations.Results: For total bacteria, the lowest viability was found in F-containing groups, regardless of the arginine concentrations and presence of CaGP. For aciduric bacteria, no significant differences were found among arginine concentrations in the presence of F. For MS, arginine concentrations did not influence MS viability in the presence of fluoride and CaGP only decreased viability at 3.2% Arg concentration. The arginine-treated groups showed the lowest acidogenicity. For ion concentrations in biofilms, CaGP showed the highest values for P; Arg+F for F; and CaGP/Arg+CaGP for Ca.Conclusion: Different concentrations of arginine did not affect the microbial viability or acidogenicity of biofilms. Moreover, 0.8% Arg did not increase ion concentration in biofilm fluid.}, }
@article {pmid39506957, year = {2024}, author = {Jones, SU and Kee, BP and Chew, CH and Yeo, CC and Chua, KH and Puah, SM}, title = {Differential expression of small RNAs in biofilm-producing clinical methicillin-susceptible Staphylococcus aureus recovered from human urine.}, journal = {Heliyon}, volume = {10}, number = {20}, pages = {e39634}, pmid = {39506957}, issn = {2405-8440}, abstract = {Bacterial small RNAs (sRNAs) play crucial roles in coordinating gene regulatory networks in various physiological processes, including biofilm formation. In this study, RNA sequencing was performed on biofilm (n = 4) and planktonic (n = 4) cells harvested at 10 h (pre-stationary phase of biofilm development) to identify biofilm-associated sRNAs in human methicillin-susceptible Staphylococcus aureus (MSSA) recovered from urine isolate. A total of 56 highly expressed sRNAs were identified with 15 overlapping sRNA genes (srn_9348, sprD, sRNA205, sRNA288, srn_2467, Sau-25, srn_2468, sRNA260, sRNA200, RsaE, sRNA397, Teg55, Teg60, RsaX05 and Teg140). Further validation through RT-qPCR analysis of nine sRNAs revealed that srn_9348 and sRNA260 were significantly expressed in the biofilm cells of urine sample. Both sRNAs were predicted to interact with mRNA genes including intracellular adhesin A (icaA) and host factor protein (hfq) involved in biofilm formation via cis-acting and trans-acting using CopraRNA analysis. Therefore, both sRNAs merit further investigations via reverse genetic approaches to elucidate their mechanism of translational regulation. In summary, the transcriptomic analysis conducted in this study offers new insights into the potential regulatory roles of sRNAs in MSSA biofilm development within the urinary environment.}, }
@article {pmid39506750, year = {2024}, author = {Chen, T and Zhou, X and Feng, R and Shi, S and Chen, X and Wei, B and Hu, Z and Peng, T}, title = {Novel function of single-target regulator NorR involved in swarming motility and biofilm formation revealed in Vibrio alginolyticus.}, journal = {BMC biology}, volume = {22}, number = {1}, pages = {253}, pmid = {39506750}, issn = {1741-7007}, mesh = {*Vibrio alginolyticus/physiology/genetics ; *Biofilms/growth &amp; development ; *Bacterial Proteins/genetics/metabolism ; *Gene Expression Regulation, Bacterial ; }, abstract = {NorR, as a single-target regulator, has been demonstrated to be involved in NO detoxification in bacteria under anaerobic conditions. Here, the norR gene was identified and deleted in the genome of Vibrio alginolyticus. The results showed that deletion of norR in Vibrio alginolyticus led to lower swarming motility and more biofilm formation on aerobic condition. Moreover, we proved that NorR from E. coli had a similar function in controlling motility. NorR overexpression led to increased resistance to oxidative stress and tetracycline. We also observed a reduced ability of the NorR-overexpressing strain to adapt to iron limitation condition. Transcriptome analysis showed that the genes responsible for bacterial motility and biofilm formation were affected by NorR. The expressions of several sigma factors (RpoS, RpoN, and RpoH) and response regulators (LuxR and MarR) were also controlled by NorR. Furthermore, Chip-qPCR showed that there is a direct binding between NorR and the promoter of rpoS. Based on these results, NorR appears to be a central regulator involved in biofilm formation and swarming motility in Vibrio alginolyticus.}, }
@article {pmid39505283, year = {2025}, author = {Lv, X and Zhang, S and Guo, S and Hu, X and Chen, H and Qiu, Z and Gao, Y and Qu, A}, title = {Interactions between SDBS and Hydrilla verticillata - epiphytic biofilm in wetland receiving STPs effluents: Nutrients removal and epiphytic microbial assembly.}, journal = {Bioresource technology}, volume = {416}, number = {}, pages = {131750}, doi = {10.1016/j.biortech.2024.131750}, pmid = {39505283}, issn = {1873-2976}, mesh = {*Wetlands ; *Biofilms ; *Hydrocharitaceae ; Nutrients ; Sewage/microbiology ; Waste Disposal, Fluid/methods ; Water Pollutants, Chemical ; Wastewater/chemistry ; Benzenesulfonates ; }, abstract = {The fate and effects of sodium dodecyl benzene sulfonate (SDBS) in sewage treatment plants effluents on nutrients and submerged macrophytes are far from clear in wetlands. This study conducted a 24-day experiment to investigate changes in nutrients and epiphytic biofilm of Hydrilla verticillata in wetlands receiving effluents with 0.5, 2 and 5 mg L[-1] SDBS. The decrease of SDBS in overlying water followed pseudo-first-order kinetic equation, with over 80 % of SDBS removal achieved. 2 and 5 mg L[-1] SDBS decreased nutrient removal efficiency, induced oxidative stress response and damaged cells of H. verticillata. SDBS altered bacterial and eukaryotic community diversity. 0.5 mg L[-1] SDBS can promote carbon fixation and methane oxidation of microorganisms. Network analysis revealed that 0.5 mg L[-1] SDBS decreased the stability of epiphytic ecosystems. Mantel tests indicated significant influences of SDBS, temperature, and total nitrogen on epiphytic microbial communities.}, }
@article {pmid39505133, year = {2025}, author = {Hu, Y and Song, Y and Cai, J and Chao, J and Gong, Y and Jiang, X and Shao, K and Tang, X and Gao, G}, title = {Stronger biogeographical pattern of bacterioplankton communities than biofilm communities along a riverine ecosystem: A local scale study of the Kaidu river in the arid and semi-arid northwest of China.}, journal = {Environmental research}, volume = {264}, number = {Pt 1}, pages = {120294}, doi = {10.1016/j.envres.2024.120294}, pmid = {39505133}, issn = {1096-0953}, mesh = {China ; *Biofilms/growth &amp; development ; *Rivers/microbiology ; *Plankton ; *Bacteria/classification/genetics ; Ecosystem ; }, abstract = {Although the biogeographical pattern and mechanisms underlying microbial assembly have been well-explored in lentic ecosystems, the relevant scenarios in lotic ecosystems remain poorly understood. By sequencing the bacterial communities in bacterioplankton and biofilm, our study detected their distance-decay relationship (DDR), and the balance between deterministic and stochastic processes, along the Kaidu river in an arid and semi-arid region of northwest China. Our results revealed that bacterioplankton and biofilm had significantly contrasting community structures. The bacterioplankton communities showed a gradually decreasing trend in alpha-diversity from the headwater to the river mouth, contrasting with the alpha-diversity of biofilm communities which was constant along the river length. Both bacterioplankton and biofilm showed significant DDRs along the 500-km river corridor with the slope of the bacterioplankton DDR being steeper than that of the biofilm DDR, which implies a stronger biogeography of bacterioplankton than biofilm. Relative to biofilm communities, the species interactions formed a denser and more complex network in the bacterioplankton communities than in the biofilm communities. Our results also revealed that there was a transition of community assembly from deterministic to stochastic processes upstream to downstream, although both the bacterioplankton and biofilm communities were mainly regulated by deterministic processes within the entire river. All these empirical results expand our knowledge of microbial ecology in an arid and semi-arid lotic ecosystem.}, }
@article {pmid39505089, year = {2024}, author = {Sathishkumar, P and Khan, F}, title = {Leveraging bacteria-inspired nanomaterials for targeted controlling biofilm and virulence properties of Pseudomonas aeruginosa.}, journal = {Microbial pathogenesis}, volume = {197}, number = {}, pages = {107103}, doi = {10.1016/j.micpath.2024.107103}, pmid = {39505089}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Pseudomonas aeruginosa/drug effects/physiology/pathogenicity ; Virulence/drug effects ; Humans ; *Pseudomonas Infections/microbiology/drug therapy ; *Anti-Bacterial Agents/pharmacology ; Nanostructures/chemistry ; Metal Nanoparticles/chemistry ; Virulence Factors/metabolism ; }, abstract = {Pseudomonas aeruginosa is an opportunistic pathogen designated as a high-priority pathogen because of its role in major healthcare-associated and nosocomial infections. Biofilm production by these bacteria is one of the adaptive resistance mechanisms to traditional antibiotics, making treatment challenging, especially for immunocompromised patients. P. aeruginosa also produces a variety of virulence factors, which aid in invasion, adhesion, persistence, and immune system protection. Recent advances in nanotechnology-based therapy, notably the application of bioinspired metal and metal-oxide nanomaterials, have been seen as a viable way to control P. aeruginosa biofilm and virulence. Because of its ease of growth and culture, synthesizing metal and metal-oxide nanomaterials using bacterial species has become one of the most environmentally benign green synthesis options. The application of bacterial-inspired nanomaterials is particularly successful for targeted control of P. aeruginosa infection due to interactions with cell membrane components and transport systems. This paper delves into and provides a complete overview of the application of bacterial-inspired metal and metal-oxide nanomaterials to treat P. aeruginosa infection by targeting biofilm and virulence characteristics. The review focused on synthesizing and applying gold, silver, copper, iron, magnetite, and zinc oxide nanomaterials to mitigate P. aeruginosa biofilm and virulence. The underlying mechanism of these metal and metal-oxide nanoparticles in relation to biofilm and virulence features has also been thoroughly discussed. The current review introduces novel approaches to treating and controlling drug-resistant P. aeruginosa using bacterial-inspired nanomaterials as a targeted therapeutic strategy.}, }
@article {pmid39504701, year = {2025}, author = {Feng, J and Zhao, J and Xiang, H and You, Z and Shi, L and Yu, Z and Qiu, Y and Yu, D and Wang, X}, title = {Establishment of continuous flow partial denitrification biofilm module with short hydraulic retention time.}, journal = {Water research}, volume = {268}, number = {Pt B}, pages = {122743}, doi = {10.1016/j.watres.2024.122743}, pmid = {39504701}, issn = {1879-2448}, mesh = {*Biofilms ; *Denitrification ; *Bioreactors ; *Nitrites/metabolism ; Nitrates/metabolism ; Waste Disposal, Fluid/methods ; Sewage/microbiology ; Bacteria/metabolism ; }, abstract = {Partial denitrification (PD) can supply essential nitrite (NO2[-]) and is supposed to promote the application of Anammox. However, PD-related research mainly involves sequencing batch reactors and activated sludge. Here, we proposed establishing PD in a continuous-flow submerged biofilm module (PD-BfM). Benefiting from employing anoxic starvation treatment to quickly start PD and transferring enriched functional bacteria onto biofilms in time, the preparation work of PD-BfM was completed within a quite short period of 21 days. With the hydraulic retention time adjusted to 50 min, PD-BfM demonstrated an impressive efficiency in generating NO2[-], achieving a nitrate-to-nitrite transformation ratio of over 75 %, even at the influent chemical oxygen demand to nitrate ratio of 4 condition. Meanwhile, the dominant genus in the biofilms was shifted from Thauera to Flavobacterium and Comamonadaceae family members. The gradient of substrate concentrations also possibly differentiated microbial communities between the top and bottom bio-carriers.}, }
@article {pmid39503496, year = {2024}, author = {Choi, A and Dong, K and Williams, E and Pia, L and Batagower, J and Bending, P and Shin, I and Peters, DI and Kaspar, JR}, title = {Erratum for Choi et al., "Human saliva modifies growth, biofilm architecture, and competitive behaviors of oral streptococci".}, journal = {mSphere}, volume = {9}, number = {12}, pages = {e0086824}, doi = {10.1128/msphere.00868-24}, pmid = {39503496}, issn = {2379-5042}, }
@article {pmid39503080, year = {2025}, author = {Sarkar, S and Yadav, M and Dey, U and Sharma, M and Mukhopadhyay, R and Kumar, A}, title = {Exploring the multifaceted role of pehR in Ralstonia solanacearum pathogenesis: enzyme activity, motility, and biofilm formation.}, journal = {Microbiological research}, volume = {290}, number = {}, pages = {127925}, doi = {10.1016/j.micres.2024.127925}, pmid = {39503080}, issn = {1618-0623}, mesh = {*Ralstonia solanacearum/genetics/pathogenicity/enzymology/physiology ; *Biofilms/growth &amp; development ; *Plant Diseases/microbiology ; *Bacterial Proteins/genetics/metabolism ; *Gene Expression Regulation, Bacterial ; *Polygalacturonase/genetics/metabolism ; *Solanum lycopersicum/microbiology ; Virulence ; Gene Expression Profiling ; Transcription Factors/genetics/metabolism ; Mutation ; }, abstract = {PehR is a transcriptional regulator among the various response regulators found in Ralstonia solanacearum, a bacterium that causes lethal wilt disease in over 450 plant species worldwide, including economically important crops such as tomato, chilli, and brinjal. PehR regulates the production of polygalacturonase, an extracellular enzyme that degrades plant cell walls, playing a significant role in bacterial wilt. Despite its significance, the precise function and regulatory mechanism of PehR in R. solanacearum are yet to be thoroughly investigated. The goal of this research is to better understand the role of PehR in R. solanacearum pathogenicity by identifying the genes and pathways that it regulates. By disrupting the pehR gene, we created the ΔpehR mutant of R. solanacearum F1C1, a strain isolated from Tezpur, Assam, India. Transcriptomic analysis revealed 667 differentially expressed genes (DEGs) in the ΔpehR mutant, with 320 upregulated and 347 downregulated compared to the wild-type F1C1 strain. GO and KEGG analyses indicated the downregulation of genes related to flagellum-dependent cell motility, membrane function, and amino acid degradation pathways in the ΔpehR mutant. EPS estimation, biochemical assays for biofilm production, motility, and enzymatic assays for cellulase and pectinase production were all used in the further characterization process. The ΔpehR mutant showed lower virulence in tomato seedlings compared to the wild-type F1C1 strain. The findings suggest that PehR could be a promising target for bacterial wilt disease control, as well as provide critical information for ensuring crop production safety around the world.}, }
@article {pmid39502993, year = {2024}, author = {Sarkar, K and Mullan, S and Menon, H}, title = {Exploring Drug Resistance: Microbial Profiles, Antibiotic Sensitivity, and Biofilm Development in Orthopedic Implant Infections.}, journal = {Cureus}, volume = {16}, number = {10}, pages = {e70938}, pmid = {39502993}, issn = {2168-8184}, abstract = {Background With the advent of and rise in antibiotic resistance globally, especially in postoperative patients, studying the antibiogram and associated factors is the need of the hour. The present study was undertaken to document the microbiological profile in postoperative orthopedic patients with the infected implant in situ and to observe the antibiotic susceptibility patterns of isolated organisms in such infections. Methods This study was conducted in the Department of Microbiology of a tertiary care hospital for six months after obtaining institutional ethical approval. A total of 236 samples from patients with orthopedic implant infections were received during the study period, out of which 53 samples with positive culture isolate were further analyzed for microbiological profile including biofilm production. All observations and demographics were recorded and analyzed using SPSS software version 21.0 (IBM Corp., Armonk, NY, USA) and represented in the form of graphs, data, and tables. Results and conclusion The study showed a culture positivity rate of 53 (23%) out of 236 samples, in which gram-negative isolates 36 (68%) were more than gram-positive isolates 17 (32%). The most common isolate was staphylococcus aureus 17 (32%) of which the majority were MRSA 13 (76%), followed by Escherichia coli 9 (17%) and Klebsiella pneumoniae 9 (17%). Out of the 53 isolates, 20 were biofilm producers. Biofilm-producing isolates were more resistant to tested routine antibiotics compared to non-biofilm. This study could represent the initial interdisciplinary effort in an ongoing process to better understand and manage orthopedic implant infections at the hospital, specifically focusing on infections related to orthopedic devices.}, }
@article {pmid39502934, year = {2024}, author = {Joko, T and Ava, S and Putri, INS and Subandiyah, S and Rohman, MS and Ogawa, N}, title = {Manuka Honey Inhibits Biofilm Formation and Reduces the Expression of the Associated Genes in Pectobacterium brasiliense.}, journal = {Scientifica}, volume = {2024}, number = {}, pages = {8837149}, pmid = {39502934}, issn = {2090-908X}, abstract = {Biofilms are major virulence factors formed by pathogenic bacteria to invade their host and maintain their colony. While biofilms usually develop on diverse solid surfaces, floating biofilms, also called pellicles, are formed at the air-liquid interface. To address the problem of biofilm formation by bacterial pathogens, honey has been extensively studied. However, information on the effect of honey on biofilm formation by plant pathogens is scarce. This study aimed to determine the effects of manuka honey on biofilm and pellicle formation by Pectobacterium brasiliense and analyze the expression of genes encoding proteins needed to form biofilm by using semiquantitative PCR and RT-qPCR. Treatment with 5% (w/v) of manuka honey significantly decreased biofilm and pellicle formation by P. brasiliense. RT-qPCR results showed that the expression of bcsA, fis, hrpL, and expI decreased 7.07-fold, 5.71-fold, 13.11-fold, and 6.26-fold, respectively, after exposure to 5% (w/v) manuka honey. Our findings reveal that manuka honey may effectively inhibit biofilm and pellicle formation.}, }
@article {pmid39502638, year = {2024}, author = {Pan, Y and Cao, L and Chen, L and Gao, L and Wei, X and Lin, H and Jiang, L and Wang, Y and Cheng, H}, title = {Enhanced Bacterial and Biofilm Adhesion Resistance of ALD Nano-TiO2 Coatings Compared to AO Coatings on Titanium Abutments.}, journal = {International journal of nanomedicine}, volume = {19}, number = {}, pages = {11143-11159}, pmid = {39502638}, issn = {1178-2013}, mesh = {*Titanium/chemistry/pharmacology ; *Biofilms/drug effects ; *Bacterial Adhesion/drug effects ; *Coated Materials, Biocompatible/chemistry/pharmacology ; *Staphylococcus aureus/drug effects/physiology ; *Surface Properties ; *Porphyromonas gingivalis/drug effects/physiology ; *Streptococcus mutans/drug effects/physiology ; *Zirconium/chemistry/pharmacology ; Dental Abutments/microbiology ; Anti-Bacterial Agents/pharmacology/chemistry ; Oxidation-Reduction ; Metal Nanoparticles/chemistry ; }, abstract = {PURPOSE: The study was intended to compare the surface properties and the bacterial and biofilm adhesion resistance of two potential antibacterial nanometer titanium dioxide (nano-TiO2) coatings on dental titanium (Ti) abutments prepared by atomic layer deposition (ALD) and the anodic oxidation (AO) techniques.<br><br>METHODS: Nano-TiO&#x2082; coatings were developed using ALD and AO techniques and applied to Ti surfaces. The surface properties and the bacterial and biofilm adhesion resistance of these coatings were evaluated against commonly used Ti and Zirconia (ZrO&#x2082;) surfaces. The chemical compositions, crystalline forms, surface topography, roughness and hydrophilicity were characterized. The antibacterial performance was assessed by the scanning electron microscope (SEM), the Colony-forming unit (CFU) assay and the 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) assay using in vitro models of Staphylococcus aureus (S. aureus), Streptococcus mutans (S. mutans), and Porphyromonas gingivalis (P. gingivalis) in both single- and mixed-species bacterial compositions.<br><br>RESULTS: ALD-prepared nano-TiO&#x2082; coatings resulted in a dense, smooth, and less hydrophilic surface with an anatase phase, significantly reducing the adhesion of the three bacteria by over 50%, comparable to ZrO&#x2082;. In contrast, AO-prepared coatings led to a less hydrophilic surface, characterized by various nano-sized pores within the oxide film. This alteration, however, had no impact on the adhesion of the three bacteria. The adhesion patterns for mixed-species bacteria were generally consistent with single-species results.<br><br>CONCLUSION: ALD-prepared nano-TiO&#x2082; coatings on Ti abutments demonstrated promising antibacterial properties comparable to ZrO&#x2082; surfaces, suggesting potential in preventing peri-implantitis. However, the bacterial and biofilm adhesion resistance of AO-produced nano-TiO&#x2082; coatings was limited.}, }
@article {pmid39502319, year = {2024}, author = {Boisen, G and Brogårdh-Roth, S and Neilands, J and Mira, A and Carda-Diéguez, M and Davies, JR}, title = {Oral biofilm composition and phenotype in caries-active and caries-free children.}, journal = {Frontiers in oral health}, volume = {5}, number = {}, pages = {1475361}, pmid = {39502319}, issn = {2673-4842}, abstract = {INTRODUCTION: During development of dental caries, oral biofilms undergo changes in microbial composition and phenotypical traits. The aim of this study was to compare the acid tolerance (AT) of plaque from two groups of children: one with severe caries (CA) and one with no caries experience (CF) and to correlate this to the microbial composition and metabolic profile of the biofilms.<br><br>METHODS: Dental plaque samples from 20 children (2-5 years) in each group were studied. The AT was analyzed by viability assessment after exposure to an acid challenge (pH 3.5), using LIVE/DEAD&#xae; BacLight&#x2122; stain and confocal microscopy. Levels of acid tolerance (AT) were evaluated using a scoring system ranging from 1 (no/low AT), to 5 (high/all AT). Metabolic profiles were investigated following a 20&#x2005;mM glucose pulse for one hour through Nuclear Magnetic Resonance (NMR). Microbial composition was characterized by 16S rRNA Illumina sequencing.<br><br>RESULTS: The mean AT score of the CA group (4.1) was significantly higher than that of the CF group (2.6, p&#x2009;<&#x2009;0.05). When comparing the end-products of glucose metabolism detected after a glucose-pulse, the CA samples showed a significantly higher lactate to acetate, lactate to formate, lactate to succinate and lactate to ethanol ratio than the CF samples (p&#x2009;<&#x2009;0.05). The bacterial characterization of the samples revealed 25 species significantly more abundant in the CA samples, including species of Streptococcus, Prevotella, Leptotrichia and Veillonella (p&#x2009;<&#x2009;0.05).<br><br>DISCUSSION: Our results show that AT in pooled plaque from the oral cavity of children with severe caries is increased compared to that in healthy subjects and that this can be related to differences in the metabolic activity and microbial composition of the biofilms. Thus, the overall phenotype of dental plaque appears to be a promising indicator of the caries status of individuals. However, longitudinal studies investigating how the AT changes over time in relation to caries development are needed before plaque AT could be considered as a prediction method for the development of dental caries.}, }
@article {pmid39501415, year = {2024}, author = {Ashkenazi, I and Longwell, M and Byers, B and Kreft, R and Ramot, R and Haider, MA and Ramot, Y and Schwarzkopf, R}, title = {Nanoparticle ultrasonication: a promising approach for reducing bacterial biofilm in total joint infection-an in vivo rat model investigation.}, journal = {Arthroplasty (London, England)}, volume = {6}, number = {1}, pages = {57}, pmid = {39501415}, issn = {2524-7948}, abstract = {BACKGROUND: While the benefits of sonication for improving periprosthetic joint infection (PJI) are well-documented, its potential therapeutic effect against bacterial biofilm remains unstudied. This study aimed to investigate the safety and efficacy of a novel nanoparticle ultrasonication process on methicillin-resistant Staphylococcus aureus (MRSA) bacterial biofilm formation in a PJI rat model.<br><br>METHODS: This novel ultrasonication process was designed to remove attached bacterial biofilm from implant and peri-articular tissues, without damaging native tissues or compromising implant integrity. Twenty-five adult Sprague-Dawley rats underwent a surgical procedure and were colonized with intra-articular MRSA, followed by the insertion of a titanium screw. Three weeks after the index surgery, the animals received a second procedure during which the screws were explanted, and soft tissue was sampled. The intraoperative use of the nanoparticle sonication treatment was employed to assess the device's safety, while ex vivo treatment on the retrieved tissue and implants was used to evaluate its efficacy.<br><br>RESULTS: Clinical and histological assessments did not indicate any macro- or micro-damage to the host tissue. Sonication of the retrieved tissues demonstrated an average bacterial removal of 2&#x2009;&#xd7;&#x2009;10[3]&#xa0;CFU/mL and 1&#x2009;&#xd7;&#x2009;10[4]&#xa0;CFU/gram of tissue. Compared to the standard-of-care group (n&#x2009;=&#x2009;10), implants treated with sonication (n&#x2009;=&#x2009;15) had significantly lower remaining bacteria, as indicated by crystal violet absorbance measurements (P&#x2009;=&#x2009;0.012).<br><br>CONCLUSIONS: This study suggests that nanoparticle sonication technology can successfully remove attached bacterial biofilms from explanted orthopedic hardware and the joint capsule, without negatively affecting native tissue. The study provides initial results supporting the potential of nanoparticle sonication as an adjuvant treatment option during a DAIR (debridement, antibiotics, and implant retention) procedure for PJI, paving the way for future clinical trials.}, }
@article {pmid39500915, year = {2024}, author = {Ramakrishnan, R and Nair, AV and Parmar, K and Rajmani, RS and Chakravortty, D and Das, D}, title = {Combating biofilm-associated Klebsiella pneumoniae infections using a bovine microbial enzyme.}, journal = {NPJ biofilms and microbiomes}, volume = {10}, number = {1}, pages = {119}, pmid = {39500915}, issn = {2055-5008}, support = {SR/MHRD-18-0021//Indian Institute of Science (Indian Institute of Science Bangalore, India)/ ; CRG/2023/000760//DST | Science and Engineering Research Board (SERB)/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Klebsiella pneumoniae/drug effects ; Animals ; *Klebsiella Infections/microbiology/drug therapy ; Cattle ; Mice ; *Anti-Bacterial Agents/pharmacology ; Microbial Sensitivity Tests ; Meropenem/pharmacology ; Humans ; Disease Models, Animal ; }, abstract = {The emergence of multidrug-resistant Klebsiella pneumoniae poses significant clinical challenges with limited treatment options. Biofilm is an important virulence factor of K. pneumoniae, serving as a protective barrier against antibiotics and the immune system. Here, we present the remarkable ability of a bovine microbial enzyme to prevent biofilm formation (IC50 2.50 μM) and degrade pre-formed K. pneumoniae biofilms (EC50 1.94 μM) by degrading the matrix polysaccharides. The treatment was effective against four different clinical K. pneumoniae isolates tested. Moreover, the enzyme significantly improved the biofilm sensitivity of a poorly performing broad-spectrum antibiotic, meropenem, and immune cells, resulting in facile biofilm clearance from the mouse wound infection. Notably, well-known powerful enzymes of the same class, cellulase, and α-amylase, were nearly inactive against the K. pneumoniae biofilms. The enzyme exhibited antibiofilm activity without showing toxicity to the mammalian and microbial cells, highlighting the potential of the enzyme for in vivo applications.}, }
@article {pmid39500825, year = {2024}, author = {Alvarez, L and Kumaran, KS and Nitha, B and Sivasubramani, K}, title = {Evaluation of biofilm formation and antimicrobial susceptibility (drug resistance) of Candida albicans isolates.}, journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]}, volume = {}, number = {}, pages = {}, pmid = {39500825}, issn = {1678-4405}, abstract = {Candida albicans comprises over 80% of isolates from all forms of human candidiasis. Biofilm formation enhances their capacity to withstand therapeutic treatments. In addition to providing protection, biofilm formation by C. albicans enhances its pathogenicity. Understanding the fundamental mechanisms underlying biofilm formation is crucial to advance our understanding and treatment of invasive Candida infections. An initial screening of 57 Candida spp. isolates using CHROMagar Candida (CHROMagar) media revealed that 46 were C. albicans. Of these, 12 isolates (33.3%) had the capacity to form biofilms. These 12 isolates were subjected to multiple biochemical and physiological tests, as well as 18 S rRNA sequencing, to confirm the presence of C. albicans. Upon analysis of their sensitivity to conventional antifungal agents, the isolates showed varying resistance to terbinafine (91.6%), voriconazole (50%), and fluconazole (42%). Among these, only CD50 showed resistance to all antifungal agents. Isolate CD50 also showed the presence of major biofilm-specific genes such as ALS3, EFG1, and BCR1, as confirmed by PCR. Exposure of CD50 to gentamicin-miconazole, a commonly prescribed drug combination to treat skin infections, resulted in elevated levels of gene expression, with ALS3 showing the highest fold increase. These observations highlight the necessity of understanding the proteins involved in biofilm formation and designing ligands with potential antifungal efficacy.}, }
@article {pmid39500459, year = {2024}, author = {Sun, L and Shewa, WA and Bossy, K and Dagnew, M}, title = {Simultaneous nitrification and denitrification framework for decentralized systems: Long-term study utilizing rope-type biofilm media under field conditions.}, journal = {The Science of the total environment}, volume = {956}, number = {}, pages = {177337}, doi = {10.1016/j.scitotenv.2024.177337}, pmid = {39500459}, issn = {1879-1026}, mesh = {*Biofilms ; *Nitrification ; *Denitrification ; *Waste Disposal, Fluid/methods ; *Bioreactors ; *Wastewater/microbiology ; Nitrogen ; Water Pollutants, Chemical ; }, abstract = {This research introduces a novel approach to achieve simultaneous nitrification-denitrification (SND) under dynamic load conditions using a cost-effective rope-type biofilm technology. The approach represents a significant advancement in wastewater treatment, particularly beneficial for remote and decentralized communities. The biofilm-based SND process was developed using a pilot-scale flow-through reactor by implementing upstream carbon management with constant-timer-based aeration control versus dynamic-sensor-based aeration control strategies. The findings indicate that adding an upstream anaerobic pretreatment process to handle excess carbon plays a substantial role in achieving a sustainable SND process under a dynamic load environment using simple aeration on-off control. The most optimal nitrification performance of 0.32 g NH3-N/m[2]/d (89 % removal) was achieved under a 1-hour ON/30-minute OFF aeration. The process sustained an average bulk liquid DO of 5.16 mg/L and 3.80 mg/L during the aeration ON and OFF periods, respectively, facilitating a 0.13 g N/m[2]/d (41 %) total inorganic nitrogen (TIN) removal, notably, implementing advanced aeration strategies driven by DO, NH3, and NO3 sensors enhanced TIN removal efficiency to 72 %. The nitrification performance remained comparable (89 % removal), resulting in 3 and 10 mg N/L effluent ammonia and TIN concentration, respectively. Additionally, utilizing two multivariate approaches accounting for 82 % and 64 % of the variance, this study discerned patterns in monitored variables and performance. Additionally, the analysis underscored the difference of bulk liquid DO levels in the biofilm versus suspended systems inhibiting the SND process. Distinct bacterial communities were established in biofilms under aerobic, anaerobic, and SND conditions, with the SND reactor showing a hierarchy of functional group and enzymes, enriched sequentially from heterotrophs to denitrifiers, nitrifiers, and anammox bacteria. These innovations underline the potential of tailored control strategies to enhance a passive biofilm-based SND process efficiency under dynamic conditions, providing scalable solutions for diverse target water quality demands in remote communities and decentralized systems.}, }
@article {pmid39499335, year = {2024}, author = {Nguyen, ANX and Thirapanmethee, K and Audshasai, T and Khuntayaporn, P and Chomnawang, MT}, title = {Insights into molecular mechanisms of phytochemicals in quorum sensing modulation for bacterial biofilm control.}, journal = {Archives of microbiology}, volume = {206}, number = {12}, pages = {459}, pmid = {39499335}, issn = {1432-072X}, mesh = {*Quorum Sensing/drug effects ; *Biofilms/drug effects ; *Phytochemicals/pharmacology ; *Anti-Bacterial Agents/pharmacology ; *Bacteria/drug effects/genetics ; Virulence Factors/metabolism/genetics ; Humans ; Bacterial Physiological Phenomena/drug effects ; Gene Expression Regulation, Bacterial/drug effects ; }, abstract = {Biofilm formation is a common mechanism by which bacteria undergo phenotypic changes to adapt to environmental stressors. The formation of biofilms has a detrimental impact in clinical settings by contributing to chronic infections and promoting antibiotic resistance. Delving into the molecular mechanisms, the quorum sensing (QS) system involves the release of chemical signals for bacterial cell-to-cell communication, which activates and regulates the expression of various genes and virulence factors, including those related to biofilm formation. Accordingly, the QS system becomes a potential target for combating biofilm-associated concerns. Natural products derived from plants have a long history of treating infectious diseases in humans due to their antimicrobial properties, making them valuable resources for screening anti-biofilm agents. This review aims to discover the mechanisms by which phytochemical agents inhibit QS, potentially offering promising new therapies for treating biofilm-associated infections. By targeting the QS system, these phytochemical agents can prevent bacterial aggregation and biofilm formation while also diminishing other bacterial virulence factors. Additionally, it is important to focus on the advancement of techniques and experiments to investigate their molecular mechanisms. A thorough understanding of these mechanisms may encourage further studies to evaluate the safety and efficacy of phytochemical agents used alone or in combination with other strategies.}, }
@article {pmid39496766, year = {2024}, author = {Korkus, J and Sałata, P and Thompson, SA and Paluch, E and Bania, J and Wałecka-Zacharska, E}, title = {The role of cydB gene in the biofilm formation by Campylobacter jejuni.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {26574}, pmid = {39496766}, issn = {2045-2322}, support = {R21 AI154078/AI/NIAID NIH HHS/United States ; 2022/47/O/NZ7/01326//Narodowe Centrum Nauki/ ; AI154078/NH/NIH HHS/United States ; "Bon doktoranta SD UPWr" no. N020/0001/21//the Wroc&#x142;aw University of Environmental and Life Sciences (Poland)/ ; }, mesh = {*Campylobacter jejuni/genetics/physiology ; *Biofilms/growth &amp; development ; *Bacterial Proteins/genetics/metabolism ; DNA Transposable Elements/genetics ; Mutagenesis, Insertional ; Mutation ; Gene Expression Regulation, Bacterial ; }, abstract = {Campylobacter jejuni is a major cause of food- and water-borne bacterial infections in humans. A key factor helping bacteria to survive adverse environmental conditions is biofilm formation ability. Nonetheless, the molecular basis underlying biofilm formation by C. jejuni remains poorly understood. Around thirty genes involved in the regulation and dynamics of C. jejuni biofilm formation have been described so far. We applied random transposon mutagenesis to identify new biofilm-associated genes in C. jejuni strain 81-176. Of 1350 mutants, twenty-four had a decreased ability to produce biofilm compared to the wild-type strain. Some mutants contained insertions in genes previously reported to affect the biofilm formation process. The majority of identified genes encoded hypothetical proteins. In the library of EZ-Tn5 insertion mutants, we found the cydB gene associated with respiration that was not previously linked with biofilm formation in Campylobacter. To study the involvement of the cydB gene in biofilm formation, we constructed a non-marked deletion cydB mutant together with a complemented mutant. We found that the cydB deletion-mutant formed a weaker biofilm of loosely organized structure and lower volume than the parent strain. In the present study, we demonstrated the role of the cydB gene in biofilm formation by C. jejuni.}, }
@article {pmid39495077, year = {2024}, author = {Backus, EA and Shugart, HJ}, title = {The vector regulation hypothesis: dynamic competition between pathogen and vector behaviors constrains Xylella fastidiosa biofilm development in sharpshooter foreguts.}, journal = {Applied and environmental microbiology}, volume = {90}, number = {11}, pages = {e0110224}, pmid = {39495077}, issn = {1098-5336}, support = {2034-22000-015-00D//U.S. Department of Agriculture (USDA)/ ; }, mesh = {*Xylella/physiology ; *Biofilms/growth &amp; development ; *Hemiptera/microbiology/physiology ; Animals ; *Insect Vectors/microbiology/physiology ; *Plant Diseases/microbiology ; Vitis/microbiology ; }, abstract = {Xylella fastidiosa (Xf) bacteria form biofilm on the cuticular surfaces of the functional foregut (precibarium and cibarium) of its vectors, xylem fluid-ingesting sharpshooter leafhoppers and spittlebugs. While much is known about Xf biofilm development and maturation in vitro, little is known about these processes in vectors. Real-time (RT)-PCR was used to quantify Xf genomes daily in the functional foreguts of blue-green sharpshooters, Graphocephala atropunctata, over 7 days of exposure to infected grapevines. Scanning electron microscopy (SEM) was used to examine Xf biofilm formation at 4 and 7 days of that time course. PCR showed populations building and reducing over a 4-day cycle. SEM revealed that foreguts at 4 days showed variability in quantity and location of bacterial attachment. Only early-stage biofilm formation occurred in low-turbulence areas of the cibarium, while high-turbulence areas of the cibarium and precibarium had rare but older, more developed macro-colonies. Biofilm was almost absent at 7 days but left behind adhesive material and remnants of prior colonization. Evidence supports the hypothesis that bacterial colonization was repeatedly interrupted and constrained by the vector. Behaviors such as egestion and enzymatic salivation likely can loosen and eject Xf biofilm, perhaps when profuse biofilm interferes with ingestion. Thus, vector acquisition of Xf is a dynamic and stochastic process of interactions between bacteria and insects. We further hypothesize for future testing that the insect can regulate this interaction. A deep understanding of Xf acquisition will aid the ongoing development of grapevine resistance to vector transmission of xylellae diseases.IMPORTANCEXylella fastidiosa (Xf) is one of the most destructive invasive plant pathogens in the world, able to hijack new vectors when it invades a region; yet the temporal interplay of bacterial colonization and insect behavior is unknown. This paper describes important findings about the process of Xf biofilm formation and maturation in a vector, contrasting similarities and differences with such formation in vitro. Results support the hypothesis that the behavior of the vector constrains and may regulate Xf biofilm formation, in dynamic competition with the bacterium. The data from this paper partly explain why Xf is so successful at invasion. Because the bacterium can be acquired and inoculated very quickly, it can move readily from old to new vectors and host plants in all-new environments. Our findings are relevant to biosecurity decisions because they demonstrate the importance of identifying potential vector species in the Xylella invasion front.}, }
@article {pmid39494899, year = {2024}, author = {Lin, Z and Liang, Z and He, S and Chin, FWL and Huang, D and Hong, Y and Wang, X and Li, D}, title = {Salmonella dry surface biofilm: morphology, single-cell landscape, and sanitization.}, journal = {Applied and environmental microbiology}, volume = {90}, number = {11}, pages = {e0162324}, pmid = {39494899}, issn = {1098-5336}, support = {Food Microbial Safety Research//NUS | Faculty of Science, National University of Singapore (NUS, FoS)/ ; Key Technology Research and Industrialization of Food for Special Medical Use Future Foods//NUS Suzhou Research institute/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Salmonella typhimurium/drug effects/physiology/growth &amp; development ; Single-Cell Analysis ; }, abstract = {In this study, Salmonella Typhimurium dry surface biofilm (DSB) formation was investigated in comparison with wet surface biofilm (WSB) development. Confocal laser scanning microscopic analysis revealed a prominent green cell signal during WSB formation, whereas a red signal predominated during DSB formation. Electron microscopy was also used to compare the features of DSB and WSB. Overall, WSB was unevenly scattered over the surface, whereas DSB was evenly dispersed. In contrast to WSB cells, which have a distinct plasma membrane and outer membrane layer, DSB cells are contained in large capsules and compressed. Next, microbiome single-cell transcriptomics was used to investigate the functional heterogeneity of the Salmonella DSB microbiome, with nine clusters successfully identified. Although over 60% of the dried cells were metabolically inactive, the rest of the Salmonella cells still demonstrated specific antioxidative and virulence capabilities, suggesting a possible concern for low-moisture food (LMF) safety. Finally, because sanitization in LMF industries must be conducted without water, a list of 39 flavonoids was tested for their combined effect with 70% isopropyl alcohol (IPA) against DSB, and morin induced the greatest reduction in the green:red ratio from 3.67 to 0.43. Significantly higher reductions of Salmonella viability in DSB were achieved by 10-, 100-, 1,000-, and 10,000-µg/mL morin (1.69 ± 0.25, 3.21 ± 0.23, 4.32 ± 0.24, and 5.18 ± 0.16 log CFU/sample reductions) than 70% IPA alone (1.55 ± 0.20 log CFU/sample reduction) (P < 0.05), indicating the potential to be formulated as a dry sanitizer for the LMF industry.IMPORTANCEDSB growth of foodborne pathogens in LMF processing environments is associated with food safety, financial loss, and compromised consumer trust. This work is the first comprehensive examination of the characteristics of Salmonella DSB while exploring its underlying survival mechanisms. Furthermore, morin dissolved in 70% IPA was proposed as an efficient dry sanitizer against DSB to provide insights into biofilm control during LMF processing.}, }
@article {pmid39494883, year = {2024}, author = {Gonçalves, B and Pires, DP and Fernandes, L and Pacheco, M and Ferreira, T and Osório, H and Soares, AR and Henriques, M and Silva, S}, title = {Biofilm matrix regulation by Candida glabrata Zap1 under acidic conditions: transcriptomic and proteomic analyses.}, journal = {Microbiology spectrum}, volume = {12}, number = {12}, pages = {e0120124}, pmid = {39494883}, issn = {2165-0497}, abstract = {The vaginal acidic environment potentiates the formation of Candida glabrata biofilms, leading to complicated and recurrent infections. Importantly, the production of matrix is known to contribute to the recalcitrant features of Candida biofilms. In this study, we reveal that Zap1 regulates the matrix of C. glabrata acidic biofilms and analyzed the modulation of their transcriptome (by microarrays) and matrix proteome (by LC-MS/MS) by Zap1. For that, the deletion mutant zap1Δ and its complemented strain zap1Δ::ZAP1 were constructed, and their biofilms were developed at pH 4 (adjusted with lactic acid). The results revealed that Zap1 is a negative regulator of the total amount of protein and carbohydrate in the biofilm matrix. Accordingly, various genes and matrix proteins with predicted functions in the regulation of carbohydrate metabolism, sugar binding, sugar transport, and adhesion (including Epa family) were repressed by Zap1. Nevertheless, the results also suggested that Zap1 is essential to the delivery and organization of some matrix components. Indeed, Zap1 was required for the secretion of 122 proteins to the matrix and induced the expression of 557 genes, including various targets involved in glucan metabolism. Additionally, Zap1 induced targets with roles in virulence, resistance to antifungals, and host immunity evasion, including yapsins, ERG family, and moonlighting proteins. Zap1 was also required for the secretion of acidic-specific matrix proteins, indicating a contribution to the response to the acidic environment. Overall, this study demonstrates that Zap1 is a relevant regulator of the biofilm matrix, contributing to a better understanding of C. glabrata acidic biofilms.IMPORTANCEThe rising prevalence of vulvovaginal candidiasis (VVC) and the increasing presence of Candida spp. with aggressive virulence features and low susceptibility to common antifungals, particularly Candida glabrata, have resulted in more severe, prolonged, and recurrent cases of VVC, with significant implications for patients. This research offers valuable insights into the molecular changes that contribute to the formation of C. glabrata biofilms in the acidic vaginal environment, representing a significant advancement in the understanding of C. glabrata's virulence. Notably, this study identified Zap1 as a critical regulator of C. glabrata biofilm matrix, with additional potential roles in adhesion, antifungal resistance, evasion of host immunity, and response to acidic conditions, making it a promising target for new therapeutic approaches. Importantly, Zap1 is the first regulator of the biofilm matrix to be identified in C. glabrata, and the elucidation of its targets (including genes and matrix proteins) lays a strong foundation for future research.}, }
@article {pmid39494760, year = {2024}, author = {Nogueira Leite, N and Garcia Sperandio, V and da Piedade Edmundo Sitoe, E and de Assis Silva, MV and Rodrigues de Alencar, E and Gonçalves Machado, S}, title = {Ozone as a promising method for controlling Pseudomonas spp. biofilm in the food industry: a systematic review.}, journal = {Biofouling}, volume = {40}, number = {10}, pages = {660-678}, doi = {10.1080/08927014.2024.2420002}, pmid = {39494760}, issn = {1029-2454}, mesh = {*Ozone/pharmacology ; *Biofilms/drug effects/growth &amp; development ; *Pseudomonas/drug effects/physiology ; *Food Industry/methods ; }, abstract = {This study aimed to evaluate the effectiveness of ozonation in controlling Pseudomonas spp. biofilm in the food industry, and present possible parameters influencing this process. The study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The search was conducted in the PubMed, EMBASE, ScienceDirect, and Scopus databases. Eleven articles published between 1993 and 2023 were included in the study, indicating that the topic has been under investigation for several decades, gaining more prominence in recent years. Studies have demonstrated the antimicrobial effect of ozone under different experimental conditions, indicating that it is an effective strategy. Furthermore, they suggest that, in addition to ozone concentration and exposure time, other parameters such as the type of materials used in processing plants, hydrodynamic conditions, water temperature, and knowledge of commonly found microorganisms contribute to the effectiveness of the process aimed at reducing microbial counts. In conclusion, the available evidence suggests that ozonation in controlling Pseudomonas spp. can be considered a promising antimicrobial strategy. More efforts are needed to adapt the different methodologies according to each industrial reality.}, }
@article {pmid39492819, year = {2024}, author = {Lee, YJ and Cao, D and Subhadra, B and De Castro, C and Speciale, I and Inzana, TJ}, title = {Relationship between capsule production and biofilm formation by Mannheimia haemolytica, and establishment of a poly-species biofilm with other Pasteurellaceae.}, journal = {Biofilm}, volume = {8}, number = {}, pages = {100223}, pmid = {39492819}, issn = {2590-2075}, abstract = {Mannheimia haemolytica is one of the bacterial agents responsible for bovine respiratory disease (BRD). The capability of M. haemolytica to form a biofilm may contribute to the development of chronic BRD infection by making the bacteria more resistant to host innate immunity and antibiotics. To improve therapy and prevent BRD, a greater understanding of the association between M. haemolytica surface components and biofilm formation is needed. M. haemolytica strain 619 (wild-type) made a poorly adherent, low-biomass biofilm. To examine the relationship between capsule and biofilm formation, a capsule-deficient mutant of wild-type M. haemolytica was obtained following mutagenesis with ethyl methanesulfonate to obtain mutant E09. Loss of capsular polysaccharide (CPS) in mutant E09 was supported by transmission electron microscopy and Maneval's staining. Mutant E09 attached to polyvinyl chloride plates more effectively, and produced a significantly denser and more uniform biofilm than the wild-type, as determined by crystal violet staining, scanning electron microscopy, and confocal laser scanning microscopy with COMSTAT analysis. The biofilm matrix of E09 contained predominately protein and significantly more eDNA than the wild-type, but not a distinct exopolysaccharide. Furthermore, treatment with DNase I significantly reduced the biofilm content of both the wild-type and E09 mutant. DNA sequencing of E09 showed that a point mutation occurred in the capsule biosynthesis gene wecB. The complementation of wecB in trans in mutant E09 successfully restored CPS production and reduced bacterial attachment/biofilm to levels similar to that of the wild-type. Fluorescence in-situ hybridization microscopy showed that M. haemolytica formed a poly-microbial biofilm with Histophilus somni and Pasteurella multocida. Overall, CPS production by M. haemolytica was inversely correlated with biofilm formation, the integrity of which required eDNA. A poly-microbial biofilm was readily formed between M. haemolytica, H. somni, and P. multocida, suggesting a mutualistic or synergistic interaction that may benefit bacterial colonization of the bovine respiratory tract.}, }
@article {pmid39492695, year = {2024}, author = {Asgari, M and Rezaeizadeh, G and Ghajari, G and Azami, Z and Behshood, P and Talebi, F and Piri Gharaghie, T}, title = {Preparation and Optimization of Hydrophilic Modified Pullulan Encapsulated Tetracycline for Significant Antibacterial and Anti-Biofilm Activity Against Stenotrophomonas maltophilia Isolates.}, journal = {Chemistry &amp; biodiversity}, volume = {}, number = {}, pages = {e202402252}, doi = {10.1002/cbdv.202402252}, pmid = {39492695}, issn = {1612-1880}, abstract = {Stenotrophomonas maltophilia (S. maltophilia), resistant to antibiotics, is a hazardous illness and a well-known worldwide public health issue. The present investigation included the preparation of formulations of tetracycline encapsulated in pullulan (referred to as HM-PULL-Tetracycline). The study aimed to assess the effectiveness of these formulations against strains of S. maltophilia in terms of their antimicrobial and anti-biofilm properties. The physicochemical characteristics of HM-PULL-Tetracycline were analyzed using a field scanning electron microscope, X-ray dispersion, Zeta potential, and dynamic light scattering analysis. The antibacterial and anti-biofilm activity was assessed using minimal biofilm inhibitory concentration and broth micro-dilution. In addition, the biocompatibility of HM-PULL-Tetracycline was assessed by investigating its cytotoxicity on the human diploid fibroblasts (HDF) normal cell line using the MTT test. The HM-PULL-Tetracycline formulation successfully prevented biofilm formation, measuring 179.7±2.66 nm in size and with an encapsulation efficiency of 84.86±3.14 %. It exhibited a biofilm growth inhibition rating of 69 % and significantly down-regulated the expression of the smf-1, rpfF, rmlA, and spgM biofilm genes in S. maltophilia strains (p<0.05). Furthermore, the HM-PULL-Tetracycline formulation exhibited a 4 to 6-fold increase in antibacterial efficacy compared to unbound tetracycline. The HM-PULL-Tetracycline formulation demonstrated cell viability of over 90 % at all doses tested against HDF normal cells. The findings of the current investigation demonstrate that HM-PULL-Tetracycline enhances the bactericidal and anti-biofilm properties without causing harm to healthy human cells. This suggests that Could be a promising approach for medication administration.}, }
@article {pmid39492539, year = {2023}, author = {Li, J and Wu, B and Xu, M and Han, X and Xing, Y and Zhou, Y and Ran, M and Zhou, Y}, title = {Nitrogen source affects non-aeration microalgal-bacterial biofilm growth progression and metabolic function during greywater treatment.}, journal = {Bioresource technology}, volume = {}, number = {}, pages = {129940}, doi = {10.1016/j.biortech.2023.129940}, pmid = {39492539}, issn = {1873-2976}, abstract = {The non-aeration microalgal-bacteria symbiotic system has attracted great attention due to excellent pollutants removal performance and low greenhouse gas emission. This study investigated how nitrogen (N) sources (ammonia, nitrate and urea) impact biofilm formation, pollutants removal and microbial niches in a microalgal-bacterial biofilm. Results showed that functional genus and enzymes contributed to organics biodegradation and carbon fixation, N transformation and assimilation enabled efficient pollutants removal without CO2 emission. Urea achieved the maximum chemical oxygen demand (89.2%) and linear alkylbenzene sulfonates (95.3%) removal. However, Nitrate significantly influenced microbial community structure and enabled the highest removal of total N (89.7%). Multifarious functional groups enabled the fast adsorption of pollutants, which favored the continuous transformation and fixing of carbon and N. But N source significantly affects the carbon and N dissimilation and fixing pathways. This study offers a promising alternative method that achieving low-carbon-footprint and cost-saving greywater treatment.}, }
@article {pmid39491739, year = {2025}, author = {Gao, D and Xu, A and Zhou, Q and Gong, X and Liang, H}, title = {New insights into biofilm formation and microbial communities in hybrid constructed wetlands with functional substrates for treating contaminated surface water.}, journal = {Bioresource technology}, volume = {416}, number = {}, pages = {131741}, doi = {10.1016/j.biortech.2024.131741}, pmid = {39491739}, issn = {1873-2976}, mesh = {*Wetlands ; *Biofilms ; Nitrogen ; Water Purification/methods ; Water Pollutants, Chemical/metabolism ; Biodegradation, Environmental ; Temperature ; Ammonia/metabolism ; Microbiota/physiology ; Nitrates/metabolism ; Bacteria/metabolism ; }, abstract = {In this study, hybrid constructed wetlands (HCW) with functional substrates (vermiculite-tourmaline modified polyurethane) were constructed to investigate nitrogen removal efficiency and metabolic cooperation mechanisms for treating rural contaminated surface water with natural temperature fluctuations. The results show that within a natural temperature fluctuation range of 9-25 °C, the HCW achieved an average nitrate nitrogen removal efficiency of 98 % and a total nitrogen removal efficiency of 76 %, with effluent total nitrogen less than 5 mg/L. The rational secretion of extracellular polymeric substance and the analysis of microbial community structure revealed that functional substrate favors biofilm formation, increases the activity of Candidatus_Brocadia and Thauera, and enhances ammonia and nitrate reduction. These findings elucidate the ecological patterns exhibited by microorganisms during the process of functional substrate intensification. Overall, this study offers valuable guidance for constructing HCW to treat contaminated surface water.}, }
@article {pmid39491627, year = {2024}, author = {Cuellar-Gaviria, TZ and Rincon-Benavides, MA and Halipci Topsakal, HN and Salazar-Puerta, AI and Jaramillo-Garrido, S and Kordowski, M and Vasquez-Martinez, CA and Nguyen, KT and Rima, XY and Rana, PSJB and Combita-Heredia, O and Deng, B and Dathathreya, K and McComb, DW and Reategui, E and Wozniak, D and Higuita-Castro, N and Gallego-Perez, D}, title = {Tissue nano-transfection of antimicrobial genes drives bacterial biofilm killing in wounds and is potentially mediated by extracellular vesicles.}, journal = {Journal of controlled release : official journal of the Controlled Release Society}, volume = {376}, number = {}, pages = {1300-1315}, pmid = {39491627}, issn = {1873-4995}, support = {DP1 DK126199/DK/NIDDK NIH HHS/United States ; DP2 EB028110/EB/NIBIB NIH HHS/United States ; R01 AR079485/AR/NIAMS NIH HHS/United States ; }, mesh = {Animals ; *Extracellular Vesicles ; *Biofilms/drug effects ; *Cathelicidins ; *Staphylococcus aureus/drug effects ; *Antimicrobial Cationic Peptides/genetics ; Transfection/methods ; Staphylococcal Infections/drug therapy/therapy ; Mice ; Mice, Inbred C57BL ; Anti-Bacterial Agents/administration &amp; dosage/pharmacology ; Female ; Male ; Cells, Cultured ; Wound Healing/drug effects ; Wound Infection/microbiology/drug therapy/therapy ; Plasmids/genetics ; }, abstract = {The emergence of bacteria that are resistant to antibiotics is on track to become a major global health crisis. Therefore, there is an urgent need for new treatment options. Here, we studied the implementation of tissue-nanotransfection (TNT) to treat Staphylococcus aureus-infected wounds by delivering gene cargos that boost the levels of naturally produced antimicrobial peptides. The Cathelicidin Antimicrobial Peptide gene (CAMP), which produces the antimicrobial peptide LL-37, was used as model gene cargo. In vitro evaluation showed successful transfection and an increase in the transcription and translation of CAMP-coding plasmid in mouse primary epithelial cells. Moreover, we found that the extracellular vesicles (EVs) derived from the transfected cells (in vitro and in vivo) carried significantly higher concentrations of CAMP transcripts and LL-37 peptide compared to control EVs, possibly mediating the trafficking of the antimicrobial contents to other neighboring cells. The TNT platform was then used in vivo on an excisional wound model in mice to nanotransfect the CAMP-coding plasmid on the edge of infected wounds. After 4 days of daily treatment, we observed a significant decrease in the bacterial load in the CAMP-treated group compared to the sham group. Moreover, histological analysis and bacterial load quantification also revealed that TNT of CAMP on S. aureus-infected wounds was effective in treating biofilm progression by reducing the bacterial load. Lastly, we observed a significant increase in macrophage recruitment to the infected tissue, a robust increase in vascularization, as well as and an increased expression of IL10 and Fli1. Our results demonstrate that TNT-based delivery of gene cargos coding for antimicrobial compounds to the wound is a promising approach for combating biofilm infections in wounds.}, }
@article {pmid39491258, year = {2023}, author = {Gao, Z and Chen, X and Wang, C and Song, J and Xu, J and Liu, X and Qian, Y and Suo, H}, title = {New strategies and mechanisms for targeting Streptococcus mutans biofilm formation to prevent dental caries: A review.}, journal = {Microbiological research}, volume = {278}, number = {}, pages = {127526}, doi = {10.1016/j.micres.2023.127526}, pmid = {39491258}, issn = {1618-0623}, abstract = {Dental caries, a prevalent oral infectious disease, is intricately linked to the biofilm formation on the tooth surfaces by oral microbes. Among these, Streptococcus mutans plays a central role in the initiation and progression of caries due to its ability to produce glucosyltransferases, synthesize extracellular polysaccharides, and facilitate bacterial adhesion and aggregation. This leads to the formation of biofilms where the bacteria metabolize dietary carbohydrates to produce acids. Therefore, devising effective strategies to inhibit S. mutans biofilm formation is crucial for dental caries prevention and oral health promotion. Though preventive measures like mechanical removal and antibacterial drugs (fluoride, chlorhexidine) exist, they pose challenges such as time consumption, short-term effectiveness, antibiotic resistance, and disruption of oral flora balance. This review provides a comprehensive overview of emerging strategies such as antimicrobial peptides, probiotics, nanoparticles, and non-thermal plasma therapies for targeted inhibition of S. mutans biofilm formation. Moreover, current research insights into the regulatory mechanisms governing S. mutans biofilm formation are also elucidated. The objective is to foster the development of innovative, efficient and safe techniques for caries prevention and treatment, thereby expanding treatment options in clinical dentistry and promoting oral health.}, }
@article {pmid39490789, year = {2024}, author = {Diaa Abdullah, H and Kamal, I and Sabry, SA and Abd Elghany, M and El Hakim Ramadan, A}, title = {Clarithromycin-tailored cubosome: A sustained release oral nano platform for evaluating antibacterial, anti-biofilm, anti-inflammatory, anti-liver cancer, biocompatibility, ex-vivo and in-vivo studies.}, journal = {International journal of pharmaceutics}, volume = {667}, number = {Pt A}, pages = {124865}, doi = {10.1016/j.ijpharm.2024.124865}, pmid = {39490789}, issn = {1873-3476}, mesh = {*Anti-Bacterial Agents/administration &amp; dosage/chemistry/pharmacology/pharmacokinetics ; *Delayed-Action Preparations ; *Clarithromycin/administration &amp; dosage/chemistry/pharmacology ; Animals ; Humans ; *Biofilms/drug effects ; Administration, Oral ; Male ; *Drug Liberation ; Anti-Inflammatory Agents/administration &amp; dosage/chemistry/pharmacology/pharmacokinetics ; Nanoparticles/chemistry ; Rats ; Particle Size ; Liver Neoplasms/drug therapy ; Hep G2 Cells ; Antineoplastic Agents/administration &amp; dosage/chemistry/pharmacology/pharmacokinetics ; Biological Availability ; Solubility ; Rats, Sprague-Dawley ; Cell Survival/drug effects ; Drug Carriers/chemistry ; }, abstract = {The clinical implication of clarithromycin (CLT) is compromised owing to its poor solubility and, subsequently, bioavailability, unpalatable taste, rapid metabolism, short half-life, frequent dosing, and adverse effects. The present investigation provides an innovative sustained-release oral drug delivery strategy that tackles these challenges. Accordingly, CLT was loaded into a cubosome, a vesicular system with a bicontinuous cubic structure that promotes solubility and bioavailability, provides a sustained release system combating short half-life and adverse effects, masks unpleasant taste, and protects the drug from destruction in gastrointestinal tract (GIT). Nine various formulas were fabricated using the emulsification method. The resulting vesicles increased the encapsulation efficiency (EE %) from 57.64 ± 0.04 % to 96.80 ± 1.50 %, the particle size (PS) from 147.30 ± 21.77 nm to 216.61 ± 5.37 nm, and the polydispersity index (PDI) values ranged from 0.117 ± 0.024 to 0.278 ± 0.073. The zeta potential (ZP) changed from -20.65 ± 2.01 mV to -33.98 ± 2.60 mV. Further, the release profile exhibited a dual release pattern within 24 h., with the percentage of cumulative release (CR %) expanding from 30.06 ± 0.42 % to 98.49 ± 2.88 %, optimized formula was found to be CC9 with EE % = 96.80 ± 1.50 %, PS = 216.61 ± 5.37 nm, ZP = -33.98 ± 2.60 mV, PDI = 0.117 ± 0.024, CR % = 98.49 ± 2.88 % and IC50 of 0.74 ± 0.19 µg/mL against HepG-2 cells with scattered unilamellar cubic non-agglomerated vesicles. Additionally, it exhibited higher anti-MRSA biofilm, relative bioavailability (2.8 fold), and anti-inflammatory and antimicrobial capacity against Pseudomonas aeruginosa, Escherichia coli, Bacillus subtilis, and Staphylococcus aureus compared to free CLT. Our data demonstrate that cubosome is a powerful nanocarrier for oral delivery of CLT, boosting its biological impacts and pharmacokinetic profile.}, }
@article {pmid39490595, year = {2024}, author = {Zhang, R and Liu, Y and Wang, S and Kang, J and Song, Y and Yin, D and Wang, S and Li, B and Zhao, X and Duan, J}, title = {Anti-bacteria, anti-biofilm, and anti-virulence activity of the synthetic compound MTEBT-3 against carbapenem-resistant Klebsiella pneumoniae strains ST3984.}, journal = {Microbial pathogenesis}, volume = {197}, number = {}, pages = {107068}, doi = {10.1016/j.micpath.2024.107068}, pmid = {39490595}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Anti-Bacterial Agents/pharmacology ; *Klebsiella pneumoniae/drug effects/genetics ; *Microbial Sensitivity Tests ; *Drug Synergism ; *Carbapenem-Resistant Enterobacteriaceae/drug effects/genetics ; Humans ; Virulence/drug effects ; Carbapenems/pharmacology ; Klebsiella Infections/microbiology/drug therapy ; Virulence Factors/genetics ; Tigecycline/pharmacology ; Meropenem/pharmacology ; Imipenem/pharmacology ; Bacterial Proteins/genetics/metabolism ; }, abstract = {PURPOSE: The rise of carbapenem-resistant Klebsiella pneumoniae (CRKP) has led to increased morbidity and mortality in clinical patients, highlighting the urgent need for effective antibacterial agents.<br><br>METHODS: We obtained a synthetic compound, MTEBT-3, using hydrophobic triphenylamine as the skeleton and hydrophilic ammonium salts. We determined the MIC of MTEBT-3 using the macro-broth susceptibility testing method. We isolated a clinical CRKP strain ST3984 and performed synergistic antibiotic sensitivity tests, time-kill assays, and resistance evolution studies. Biofilm formation under sub-MIC conditions was evaluated using crystal violet staining and CLSM. Additionally, biofilm proteins and polysaccharides were quantified. We assessed the bactericidal mechanism of MTEBT-3 by examining the integrity of CRKP bacterial cell membranes and analyzing the transcription of virulence-regulating genes via quantitative real-time PCR.<br><br>RESULTS: MTEBT-3 exhibited broad-spectrum antibacterial activity with a low resistance rate, achieving the MIC of 8&#xa0;&#x3bc;g/mL. The compound displayed additive effects with meropenem and imipenem and synergistic effects with tigecycline. It maintained its efficacy over multiple bacterial generations, with no significant increase in resistance observed. Under sub-MIC conditions, the biomass of biofilms was significantly reduced, and the levels of proteins and polysaccharides within the biofilms were markedly lowered in a concentration-dependent manner. The bactericidal mechanism of MTEBT-3 involved disrupting the integrity of CRKP bacterial cell membranes, leading to increased permeability. Quantitative real-time PCR results showed that MTEBT-3 effectively suppressed the expression of key virulence genes, including fimH, wbbM, rmpA, and rmpA2, which are associated with biofilm formation and bacterial adhesion.<br><br>CONCLUSION: The significant antimicrobial activity of MTEBT-3 against clinically isolated CRKP, along with its synergistic or additive effects with commonly used antibiotics, positions it as a promising candidate for treatment. Its ability to disrupt biofilm formation and reduce virulence factor expression further underscores its potential in managing CRKP infections.}, }
@article {pmid39490093, year = {2025}, author = {Chen, H and Zhang, S and Wang, H and Ma, X and Wang, M and Yu, P and Shi, B}, title = {Co-selective effect of dissolved organic matter and chlorine on the bacterial community and their antibiotic resistance in biofilm of drinking water distribution pipes.}, journal = {Water research}, volume = {268}, number = {Pt A}, pages = {122664}, doi = {10.1016/j.watres.2024.122664}, pmid = {39490093}, issn = {1879-2448}, mesh = {*Biofilms/drug effects ; *Chlorine/pharmacology ; *Drinking Water/microbiology ; Bacteria/drug effects ; Drug Resistance, Microbial/genetics/drug effects ; Water Purification ; Disinfection/methods ; }, abstract = {The proliferation of pathogenic bacteria and antibiotic resistance genes (ARGs) in the biofilm of drinking water distribution pipes poses a serious threat to human health. This work adopted 15 polyethylene (PE) pipes to study the co-selective effect of dissolved organic matter (DOM) and chlorine on the bacterial community and their antibiotic resistance in biofilm. The results indicated that ozone and granular activated carbon (O3-GAC) filtration effectively removed lignins and proteins from DOM, and chlorine disinfection eliminated carbohydrate and unsaturated hydrocarbons, which both contributed to the inhibition of bacterial growth and biofilm formation. After O3-GAC and disinfection treatment, Porphyrobacter, unclassified_d_bacteria, and Sphingopyxis dominated in the biofilm bacterial community. Correspondingly, the bacterial metabolism pathways, including the phosphotransferase system, phenylalanine, tyrosine and tryptophan biosynthesis, ABC transporters, and starch and sucrose metabolism, were downregulated significantly (p < 0.05), compared to the sand filtration treatment. Under such a situation, extracellular polymeric substances (EPS) secretion was inhibited in biofilm after O3-GAC and disinfection treatment, postponing the interaction between EPS protein and pipe surface, preventing bacteria, especially pathogens, from adhering to the pipe surface to form biofilm, and restraining the spread of ARGs. This study revealed the effects of various water filtration and disinfection processes on bacterial growth, metabolism, and biofilm formation on a molecular level, and validated that the O3-GAC filtration followed by chlorine disinfection is an effective and promising pathway to control the microbial risk of drinking water.}, }
@article {pmid39489326, year = {2024}, author = {Jo, J and Jeon, MJ and Park, SK and Shin, SJ and Kim, BI and Park, JW}, title = {Anti-cariogenic effect of experimental resin cement containing ursolic acid using dental microcosm biofilm.}, journal = {Journal of dentistry}, volume = {151}, number = {}, pages = {105447}, doi = {10.1016/j.jdent.2024.105447}, pmid = {39489326}, issn = {1879-176X}, mesh = {*Biofilms/drug effects ; Humans ; *Triterpenes/pharmacology ; *Ursolic Acid ; *Saliva/microbiology ; *Resin Cements/pharmacology/chemistry ; *Dental Caries/microbiology ; *X-Ray Microtomography ; Composite Resins/pharmacology/chemistry ; Inlays ; Molar ; Dental Enamel/drug effects/microbiology ; Cariostatic Agents/pharmacology ; }, abstract = {OBJECTIVE: This study aimed to assess the anticariogenic effects of resin cement containing varying ursolic acid (UA) concentrations and to determine the optimal UA concentrations in the microcosm biofilm model.<br><br>MATERIALS AND METHODS: Experimental resin cements with UA concentrations of 0, 0.1, 0.5, 1.0, and 2.0 wt% were prepared. Class I cavities were prepared on 50 extracted human molars and restored with composite inlays and experimental resin cements. Tooth samples were subjected to artificial caries induction for 10 days in a microcosm biofilm model using human saliva as an inoculum, and then mineral changes were evaluated using quantitative light-induced fluorescence (&#x394;F and &#x394;Q) and micro-computed tomography (CT). The bacterial composition of the human saliva was analyzed by 16 s RNA microbiome profiling. One-way analysis of variance with Tukey and Duncan post-hoc tests was employed for statistical analysis (p < 0.05).<br><br>RESULTS: As the UA concentration increased, resin cement decreased &#x394;F and &#x394;Q before and after caries induction but showed a significant difference only in &#x394;Q at UA concentration &#x2265; 1.0 % (p < 0.05). The gray value analysis result of micro CT also showed a significant difference at UA concentration &#x2265; 1.0 % (p < 0.05). In the human saliva analysis, bacterial composition remained within normal oral microbiota ranges.<br><br>CONCLUSION: Resin cements containing at least 1.0 % of UA exhibited an anticariogenic effect on dental microcosm biofilms.<br><br>CLINICAL RELEVANCE: To reduce the failure of restorations, it is essential to prevent the occurrence of secondary caries. The application of UA in resin cement can be utilized to prevent the formation of secondary caries due to the anticariogenic effect of UA.}, }
@article {pmid39489123, year = {2024}, author = {Silva, NBS and Calefi, GG and Teixeira, SC and Melo Fernandes, TA and Tanimoto, MH and Cassani, NM and Jardim, ACG and Vasconcelos Ambrosio, MAL and Veneziani, RCS and Bastos, JK and Ferro, EAV and de Freitas Barbosa, B and Silva, MJB and Sabino-Silva, R and Martins, CHG}, title = {Brazilian red propolis reduces the adhesion of oral biofilm cells and the Toxoplasma gondii intracellular proliferation.}, journal = {Biomedicine &amp; pharmacotherapy = Biomedecine &amp; pharmacotherapie}, volume = {181}, number = {}, pages = {117627}, doi = {10.1016/j.biopha.2024.117627}, pmid = {39489123}, issn = {1950-6007}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Propolis/pharmacology/chemistry ; Animals ; *Toxoplasma/drug effects/growth &amp; development ; *Caenorhabditis elegans/drug effects ; Brazil ; *Microbial Sensitivity Tests ; Molecular Docking Simulation ; Mouth/microbiology ; Larva/drug effects ; Cell Proliferation/drug effects ; Anti-Infective Agents/pharmacology ; }, abstract = {Infectious diseases remain as a significant cause of thousands of deaths annually worldwide. Therefore, this study aimed to investigate the antimicrobial and antiparasitic activity of the crude hydroalcoholic extract and compounds isolated from Brazilian Red Propolis (BRP) against oral pathogens and Toxoplasma gondii, using in vitro, in vivo and in silico approaches. Antimicrobial and synergistic activities were determined using the broth dilution method and the checkerboard assay, respectively. Antibiofilm activity was evaluated by staining with 2 % crystal violet and counting microorganisms. In vivo infection was carried out in Caenorhabditis elegans AU37 larvae and in silico analysis was performed using molecular docking simulations. The effect on growth modulation of T. gondii was evaluated through a β-galactosidase colorimetric assay. Minimum Inhibitory Concentration values ranged from 3.12 to 400 µg/mL. Biofilm Minimum Inhibitory Concentration (MICB50) values ranged from 6.25 to 375 µg/mL, with a significant reduction in the number of viable cells. Furthermore, Guttiferone E and the crude extract reduced cell aggregation and caused damage to the biofilm cell wall. The highest concentrations of the crude extract and Guttiferone E increased the survival and reduced the risk of death of infected and treated larvae. Guttiferone E and Oblongifolin B inhibited the intracellular proliferation of T. gondii and demonstrated several targets of action against bacteria and T. gondii through in silico analysis. These data demonstrate that BRP has antimicrobial and antiparasitic activity against pathogens of clinical relevance, and can be used in the future as phytomedicines.}, }
@article {pmid39487302, year = {2024}, author = {Kulayta, K and Zerdo, Z and Seid, M and Dubale, A and Manilal, A and Kebede, T and Alahmadi, RM and Raman, G and Akbar, I}, title = {Biofilm formation and antibiogram profile of bacteria from infected wounds in a general hospital in southern Ethiopia.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {26359}, pmid = {39487302}, issn = {2045-2322}, mesh = {Humans ; Ethiopia/epidemiology ; *Biofilms/drug effects/growth &amp; development ; Female ; Male ; Adult ; *Wound Infection/microbiology/epidemiology/drug therapy ; *Hospitals, General ; Middle Aged ; Cross-Sectional Studies ; *Anti-Bacterial Agents/pharmacology/therapeutic use ; *Microbial Sensitivity Tests ; Young Adult ; Adolescent ; Bacteria/drug effects/isolation &amp; purification ; Drug Resistance, Multiple, Bacterial ; Aged ; Bacterial Infections/microbiology/drug therapy/epidemiology ; Prevalence ; }, abstract = {Biofilm-producing bacteria associated with wound infections exhibit exceptional drug resistance, leading to an escalation in morbidity, worse clinical outcomes (including delay in the healing process), and an increase in health care cost, burdening the whole system. This study is an attempt to estimate the prevalence and the relationship between the biofilm-forming capacity and multi-drug resistance of wound bacterial isolates. The findings intended to help clinicians, healthcare providers and program planners and to formulate an evidence-based decision-making process, especially in resource-limited healthcare settings. This study was done to assess the prevalence of bacterial infections in wounds and the antibiogram and biofilm-forming capacity of those bacteria in patients with clinical signs and symptoms, attending a General Hospital in southern Ethiopia. A cross-sectional study was performed in Arba Minch General Hospital from June to November 2021. The study participants comprised 201 patients with clinically infected wounds. Demographic and clinical data were gathered via a structured questionnaire. Specimens from wounds were taken from each participant and inoculated onto a series of culture media, namely MacConkey agar, mannitol salt agar, and blood agar, and different species were identified using a number of biochemical tests. Antimicrobial susceptibility tests were performed by means of the Kirby-Bauer disc diffusion technique following the guidelines of the Clinical and Laboratory Standards Institute. A micro-titer plate method was employed to detect the extent of biofilm formation. Bivariable and multivariable logistic regression models were applied to analyse the association between dependent and independent variables, and P values ≤ 0.05 were considered as statistically significant. Data analyses were done with Statistical Package for the Social Sciences version 25. Out of the 201 clinically infected wounds, 165 were found culture-positive with an overall prevalence of 82% (95% CI: 75.9-86.9). In total, 188 bacteria were recovered; 53.1% of them were Gram-positive cocci. The often-isolated bacterial species were Staphylococcus aureus, 38.3% (n = 72), and Pseudomonas aeruginosa, 16.4% (n = 31). The Gram-positive isolates showed considerable resistance against penicillin, 70%, and somewhat strong resistance against tetracycline, 57.7%. Gram-negative isolates showed severe resistance to ampicillin, 80.68%. The overall multi-drug resistance (MDR) among isolates was 48.4%. Extended beta-lactamase (ESBL)-producing Gram-negatives and methicillin-resistant Staphylococcus aureus (MRSA) accounted for 49 and 41.67%, respectively; 62.2% of the isolates were biofilm formers and were correlated statistically with MDR, ESBL producers, and MRSA (P < 0.005). The extent of biofilm formation and the prevalence of MDR bacteria associated with infected wounds hint at a public health threat that needs immediate attention. Thus, a more balanced and comprehensive wound management approach and antimicrobial stewardship program are essential in the study setting.}, }
@article {pmid39485840, year = {2024}, author = {Gui, Y and Sun, Q and Li, K and Lin, L and Zhou, H and Ma, J and Li, C}, title = {Bioinspired gelated cell sheet-supported lactobacillus biofilm for aerobic vaginitis diagnosis and treatment.}, journal = {Science advances}, volume = {10}, number = {44}, pages = {eadq2732}, pmid = {39485840}, issn = {2375-2548}, mesh = {Female ; *Biofilms/drug effects/growth &amp; development ; Animals ; *Lactobacillus/physiology ; Mice ; Humans ; *Probiotics ; Disease Models, Animal ; Vaginosis, Bacterial/therapy/microbiology/drug therapy/diagnosis ; Vagina/microbiology ; Escherichia coli/drug effects ; Escherichia coli Infections/therapy/microbiology/drug therapy ; Anti-Bacterial Agents/pharmacology/therapeutic use ; }, abstract = {Aerobic vaginitis (AV) is a long-standing inflammatory disease that affects female patients. The use of antibiotics is a common means for AV treatment, but it will indiscriminately kill both pathogenic bacteria and beneficial strains, which easily causes vaginal dysbacteriosis and infection recurrence. Herein, we describe a bioinspired strategy for fabricating gelated cell sheet-supported lactobacillus biofilms (GCS-LBs) for AV treatment. Compared with common planktonic probiotic formulations, probiotic biofilms forming on a robust GCS exhibit enhanced stress tolerance and better colonization capacity in the mouse vagina. Moreover, DNA nanodevices are decorated on the GCS and dynamically report the microenvironment change of biofilms for timely evaluating bacterium activity, both in vitro and in vivo. Consequently, GCS-LBs are used for treating AV in an Escherichia coli-infected mouse model, which shows enhanced therapeutic efficacy compared with conventional antibiotic or lactobacillus monotherapy. Overall, the GCS-LB shows promise as a potent multifunctional tool to combat bacterial infection.}, }
@article {pmid39484003, year = {2024}, author = {Singh, AK and Salkar, Y and Batra, P and Arora, G and Mahesh, S}, title = {A comparative evaluation of the antimicrobial efficacy of Chlorhexidine and Chlorine dioxide on self-ligating brackets contaminated with Streptococcus mutans biofilm- An In vitro study.}, journal = {Journal of oral biology and craniofacial research}, volume = {14}, number = {6}, pages = {751-755}, pmid = {39484003}, issn = {2212-4268}, abstract = {OBJECTIVE: To evaluate and compare antimicrobial efficacy of Chlorhexidine and Chlorine dioxide mouthwashes on S.mutans biofilm created on metal and ceramic self-ligating brackets.<br><br>MATERIALS AND METHODS: A total of 162 metal and ceramic self-ligating brackets (3M&#x2122; SmartClip&#x2122; &amp; Clarity SL&#x2122;) were randomly divided into 3 groups and 2 subgroups. Standard procedures were followed to coat all brackets with S.mutans biofilm. The biofilms were cultivated which were then subjected to the effects of the mouthwashes. Quantitative assessment was carried out by comparing the number of viable colonies of S.mutans. A Mann-Whitney U test was used to compare the data between the experimental and control groups. (p&#xa0;<&#xa0;0.05).<br><br>RESULT: When compared to untreated controls the antimicrobial efficacy of Chlorhexidine Digluconate and Chlorine Dioxide mouthwashes was found to be statistically significant (p&#xa0;=&#xa0;0.00). The comparison between Chlorhexidine digluconate and Chlorine dioxide mouthwashes was not statistically significant in Ceramic self-ligating group (p&#xa0;=&#xa0;0.502) and statistically significant in Metal self-ligating group (p&#xa0;=&#xa0;0.001).<br><br>CONCLUSION: S mutans colonies on metal and ceramic self-ligating brackets can be reduced effectively by Chlorhexidine digluconate and Chlorine dioxide mouthwashes. Chlorhexidine digluconate more effective for metal bracket group. Both mouthwashes had comparable antimicrobial effectiveness, with the difference in the number of viable colonies following exposure for ceramic bracket groups.}, }
@article {pmid39483571, year = {2024}, author = {Sahoo, K and Meshram, S}, title = {Biofilm Formation in Chronic Infections: A Comprehensive Review of Pathogenesis, Clinical Implications, and Novel Therapeutic Approaches.}, journal = {Cureus}, volume = {16}, number = {10}, pages = {e70629}, pmid = {39483571}, issn = {2168-8184}, abstract = {Biofilms are intricate microbial communities on various surfaces, including medical devices and biological tissues, encased within a protective matrix of extracellular polymeric substances. Their formation and persistence are significant factors in the pathogenesis of chronic infections, contributing to the complexity of treatment and increased resistance to antimicrobial agents. This review explores the multifaceted nature of biofilms, focusing on their formation, structure, and the genetic and environmental factors that contribute to their resilience. Biofilms are particularly problematic in chronic infections, such as those associated with medical implants and persistent wounds, due to their ability to evade both the host immune response and conventional therapeutic strategies. The review also discusses the current challenges in diagnosing biofilm-associated infections and the limitations of existing treatment options. Emerging therapeutic approaches, including novel antibiofilm agents, physical disruption techniques, and biological therapies such as phage therapy, are examined for their potential to improve treatment outcomes. Innovations in drug delivery systems and preventive measures, such as biofilm-resistant materials, are also highlighted as promising developments. This comprehensive overview aims to provide insights into the mechanisms of biofilm-related infections and to guide future research and clinical practice. This review contributes to the ongoing efforts to enhance patient care and combat the growing challenge of antimicrobial resistance by addressing the critical need for effective strategies to manage and prevent biofilm-associated chronic infections.}, }
@article {pmid39483311, year = {2024}, author = {Altavas, PJD and Abaya, ARG and Abella, RVTD and Acosta, DLA and Aguilar, AC and Aguinaldo, CAV and Aguirre, KLL and Amante, CTC and Amora, KB and Anarna, GAR and Andrada, RT and Ang, GGT and Angobung, JCR and Aquino, AV and Arabis, DAP and Awitan, HLG and Baccay, MFD and Bagsic, CAJB and Baldosano, TV and Maramba-Lazarte, CC}, title = {Antimicrobial Activity of Ardisia serrata (Cavs.) Pers. Ethanolic and Aqueous Leaf Extract on the Growth and Biofilm Formation of Selected Bacterial Isolates.}, journal = {Acta medica Philippina}, volume = {58}, number = {18}, pages = {91-97}, pmid = {39483311}, issn = {2094-9278}, abstract = {BACKGROUND: Ardisia serrata (Aunasin) is an endemic Philippine plant of the family Primulaceae, with several studies showing the genus Ardisia as having potential antibacterial, antiangiogenic, cytotoxic, and antipyretic properties.<br><br>OBJECTIVE: This study aims to determine the antibacterial and antibiofilm-forming activity of Ardisia serrata ethanolic and aqueous extracts on Escherichia coli, Methicillin-Sensitive Staphylococcus aureus (MSSA), and Methicillin-Resistant Staphylococcus aureus (MRSA).<br><br>METHODS: This is an experimental study testing the activity against bacterial strains of E. coli, MSSA, and MRSA using ethanolic and aqueous extracts of A. serrata leaves. Microtiter susceptibility and biofilm inhibition assays were done with two-fold dilutions of the extract against the selected strains using spectrophotometry with optical density (OD) at 600 nm and 595 nm, respectively, to quantify bacterial growth and biofilm inhibition. The bacterial susceptibility and biofilm inhibition activity was reported as percent inhibition (PI). Minimum inhibitory concentration (MIC), and minimum biofilm inhibition concentration (MBIC) values were obtained using logarithmic regression of the PI values.<br><br>RESULTS: A. serrata ethanolic extracts showed weak growth inhibitory activity against MSSA and MRSA with minimum inhibitory concentration (MIC) values of 2.6192 and 3.2988 mg/mL, respectively, but no biofilm inhibition activity was noted, while the aqueous extracts exhibited negligible biofilm inhibition activity against MSSA and MRSA with minimum biofilm inhibition concentration (MBIC) values of 13.5972 and 8964.82 mg/mL, respectively, and with no growth inhibition activity. Both ethanolic and aqueous extracts showed no growth inhibition and biofilm inhibition activities against E. coli.<br><br>CONCLUSION: Staphylococcus aureus is susceptible to the bioactivity of the leaf extracts of A. serrata and has potential to be used as an antibacterial in the treatment of infectious diseases.}, }
@article {pmid39483118, year = {2024}, author = {Gustafson, AM and Larrain, CM and Friedman, LR and Repkorwich, R and Anidi, IU and Forrest, KM and Fennelly, KP and Carr, SR}, title = {Novel management of pseudomonas biofilm-like structure in a post-pneumonectomy empyema.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1458652}, pmid = {39483118}, issn = {2235-2988}, mesh = {Humans ; *Biofilms/drug effects/growth &amp; development ; Male ; *Pneumonectomy ; *Pseudomonas aeruginosa/drug effects ; *Pseudomonas Infections/drug therapy/microbiology ; *Anti-Bacterial Agents/therapeutic use/pharmacology ; Empyema, Pleural/microbiology/drug therapy/surgery/etiology ; Middle Aged ; Treatment Outcome ; Debridement ; }, abstract = {We present a patient with a post-pneumonectomy empyema refractory to surgical debridement and systemic antibiotics. The patient initially presented with a bronchopleural fistula and pneumothorax secondary to tuberculosis (TB) destroyed lung, which required a pneumonectomy with Eloesser flap. Ongoing pleural infection delayed the closure of the Eloesser flap, and thoracoscopic inspection of his chest cavity revealed a green, mucous biofilm-like structure lining the postpneumonectomy pleural cavity. Cultures identified pan-susceptible Pseudomonas aeruginosa. Despite debriding this biofilm-like structure and administering systemic antibiotics, the patient continued to show persistent signs of infection and regrowth of the film. We employed a novel approach to dissolve the biofilm-like structure using intrapleural dornase alfa followed by intrapleural antibiotic washes. After 3 weeks of daily washes, repeat inspection demonstrated the biofilm-like structure had completely resolved. Resolving the pseudomonas biofilm-like structure allowed permanent closure of his chest without further need for systemic antibiotics. At follow up 3 months later, he showed no sequalae. This treatment option can be an important adjunct to improve likelihood of chest closure in patients with post-pneumonectomy empyema that resists standard treatment options due to biofilm formation.}, }
@article {pmid39482677, year = {2024}, author = {Oo, T and Saiboonjan, B and Mongmonsin, U and Srijampa, S and Srisrattakarn, A and Tavichakorntrakool, R and Chanawong, A and Lulitanond, A and Roytrakul, S and Sutthanut, K and Tippayawat, P}, title = {Effectiveness of co-cultured Myristica fragrans Houtt. seed extracts with commensal Staphylococcus epidermidis and its metabolites in antimicrobial activity and biofilm formation of skin pathogenic bacteria.}, journal = {BMC complementary medicine and therapies}, volume = {24}, number = {1}, pages = {380}, pmid = {39482677}, issn = {2662-7671}, support = {PR65-1-Immune-001//The Fundamental Fund of Khon Kaen University/ ; PR65-311 1-002//The Research and Academic Services, Khon Kaen University through Research Program Year 2022/ ; }, mesh = {*Biofilms/drug effects ; *Seeds ; *Staphylococcus epidermidis/drug effects ; *Plant Extracts/pharmacology ; *Myristica/chemistry ; *Coculture Techniques ; *Staphylococcus aureus/drug effects ; Humans ; Skin/microbiology ; Anti-Bacterial Agents/pharmacology ; }, abstract = {BACKGROUND: Skin commensal bacteria (Staphylococcus epidermidis) can help defend against skin infections, and they are increasingly being recognized for their role in benefiting skin health. This study aims to demonstrate the activities that Myristica fragrans Houtt. seed extracts, crude extract (CE) and essential oil (EO), have in terms of promoting the growth of the skin commensal bacterium S. epidermidis and providing metabolites under culture conditions to disrupt the biofilm formation of the common pathogen Staphylococcus aureus.<br><br>METHODS: The culture supernatant obtained from a co-culture of S. epidermidis with M. fragrans Houtt. seed extracts in either CE or EO forms were analyzed using gas chromatography-mass spectrometry (GC-MS) and liquid chromatography tandem mass spectrometry (LC-MS/MS), in silico investigations, and applied to assess the survival and biofilm formation of S. aureus.<br><br>RESULTS: The combination of commensal bacteria with M. fragrans Houtt. seed extract either CE or EO produced metabolic compounds such as short-chain fatty acids and antimicrobial peptides, contributing to the antimicrobial activity. This antimicrobial activity was related to downregulating key genes involved in bacterial adherence and biofilm development in S. aureus, including cna, agr, and fnbA.<br><br>CONCLUSION: These findings suggest that using the culture supernatant of the commensal bacteria in combination with CE or EO may provide a potential approach to combat biofilm formation and control the bacterial proliferation of S. aureus. This may be a putative non-invasive therapeutic strategy for maintaining a healthy skin microbiota and preventing skin infections.}, }
@article {pmid39482329, year = {2024}, author = {Lander, SM and Fisher, G and Everett, BA and Tran, P and Prindle, A}, title = {Author Correction: Secreted nucleases reclaim extracellular DNA during biofilm development.}, journal = {NPJ biofilms and microbiomes}, volume = {10}, number = {1}, pages = {116}, doi = {10.1038/s41522-024-00595-5}, pmid = {39482329}, issn = {2055-5008}, }
@article {pmid39488150, year = {2024}, author = {Pyl, M and Ben Gharbia, H and Sdiri, K and Oberhänsli, F and Friedrich, J and Danis, B and Metian, M}, title = {Comparison of biofilm-covered microplastics and sand particles as vectors of PCB-153 to Paracentrotus lividus.}, journal = {Aquatic toxicology (Amsterdam, Netherlands)}, volume = {277}, number = {}, pages = {107113}, doi = {10.1016/j.aquatox.2024.107113}, pmid = {39488150}, issn = {1879-1514}, mesh = {Animals ; *Biofilms ; *Water Pollutants, Chemical ; *Paracentrotus ; *Polychlorinated Biphenyls ; *Microplastics/toxicity ; Sand ; Bioaccumulation ; }, abstract = {The microplastics (MPs) vector effect of environmental contaminants (such as polychlorinated biphenyls-PCBs) to organism tissues is currently one of the major concerns regarding MPs pollution in the marine environment. The relative importance of MPs as vectors for the bioaccumulation of contaminants to marine organisms compared to other naturally occurring particles has been poorly investigated and never by using biofilm-covered particles. The present study compares the role of biofilm-covered microplastics and sand particles as vectors for the transfer and bioaccumulation of [14]C-PCB-153 into various body compartments of the sea urchin Paracentrotus lividus. After 14 days of exposure, similar transfer efficiency of [14]C-PCB-153 from both types of biofilm-covered particles was obtained (t-test, p-val = 0.43). The particle type was not found to affect the concentration (two-way ANOVA, p-valper dry weight = 0.92, p-valper lipid weight = 0.80) and distribution (two-way ANOVA, p-val = 0.85) of [14]C-PCB-153 among the different body compartments of sea urchins. These findings suggest that biofilm-covered MPs located on the seafloor may act as similar vectors for the bioaccumulation of PCB-153 in sea urchin tissues compared to other biofouled natural particles such as sand. Overall, the outcomes of this present work align with the growing consensus among various research groups that MPs-mediated bioaccumulation of co-contaminants would be negligible compared to natural bioaccumulation pathways in relation to their abundance in the ocean.}, }
@article {pmid39480794, year = {2024}, author = {Khatibzadeh, SM and Dahlgren, LA and Caswell, CC and Ducker, WA and Werre, SR and Bogers, SH}, title = {Equine bone marrow-derived mesenchymal stromal cells reduce established S. aureus and E. coli biofilm matrix in vitro.}, journal = {PloS one}, volume = {19}, number = {10}, pages = {e0312917}, pmid = {39480794}, issn = {1932-6203}, mesh = {*Biofilms/drug effects/growth &amp; development ; Horses ; Animals ; *Escherichia coli/drug effects/physiology ; *Mesenchymal Stem Cells/cytology/drug effects ; *Staphylococcus aureus/drug effects/physiology ; *Amikacin/pharmacology ; Anti-Bacterial Agents/pharmacology ; Bone Marrow Cells/cytology ; Coculture Techniques ; }, abstract = {Biofilms reduce antibiotic efficacy and lead to complications and mortality in human and equine patients with orthopedic infections. Equine bone marrow-derived mesenchymal stromal cells (MSC) kill planktonic bacteria and prevent biofilm formation, but their ability to disrupt established orthopedic biofilms is unknown. Our objective was to evaluate the ability of MSC to reduce established S. aureus or E. coli biofilms in vitro. We hypothesized that MSC would reduce biofilm matrix and colony-forming units (CFU) compared to no treatment and that MSC combined with the antibiotic, amikacin sulfate, would reduce these components more than MSC or amikacin alone. MSC were isolated from 5 adult Thoroughbred horses in antibiotic-free medium. 24-hour S. aureus or E. coli biofilms were co-cultured in triplicate for 24 or 48 hours in a transwell plate system: untreated (negative) control, 30 μg/mL amikacin, 1 x 106 passage 3 MSC, and MSC with 30 μg/mL amikacin. Treated biofilms were photographed and biofilm area quantified digitally. Biomass was quantified via crystal violet staining, and CFU quantified following enzymatic digestion. Data were analyzed using mixed model ANOVA with Tukey post-hoc comparisons (p < 0.05). MSC significantly reduced S. aureus biofilms at both timepoints and E. coli biofilm area at 48 hours compared to untreated controls. MSC with amikacin significantly reduced S. aureus biofilms versus amikacin and E. coli biofilms versus MSC at 48 hours. MSC significantly reduced S. aureus biomass at both timepoints and reduced S. aureus CFU at 48 hours versus untreated controls. MSC with amikacin significantly reduced S. aureus biomass versus amikacin at 24 hours and S. aureus and E. coli CFU versus MSC at both timepoints. MSC primarily disrupted the biofilm matrix but performed differently on S. aureus versus E. coli. Evaluation of biofilm-MSC interactions, MSC dose, and treatment time are warranted prior to testing in vivo.}, }
@article {pmid39480631, year = {2024}, author = {Lattar, SM and Schneider, RP and Eugenio, VJ and Padilla, G}, title = {High release of Candida albicans eDNA as protection for the scaffolding of polymicrobial biofilm formed with Staphylococcus aureus and Streptococcus mutans against the enzymatic activity of DNase I.}, journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]}, volume = {55}, number = {4}, pages = {3921-3932}, pmid = {39480631}, issn = {1678-4405}, support = {2017/07339-4//FAPESP/ ; 30201*52//FUNDEP/ ; }, mesh = {*Biofilms/growth &amp; development ; *Deoxyribonuclease I/metabolism ; *Candida albicans/genetics/physiology/drug effects ; *Staphylococcus aureus/genetics/physiology/drug effects ; *Streptococcus mutans/genetics/enzymology/drug effects/physiology/metabolism ; DNA, Fungal/genetics ; Microbial Interactions ; }, abstract = {This study aimed to determine the protective role of the high release of C. albicans extracellular DNA (eDNA) in a polymicrobial biofilm formed by S. aureus and S. mutans in the course of DNase I treatment. A tube-flow biofilm bioreactor was developed to mimic biofilm formation in the oral cavity. eDNA release was quantified by real-time PCR (qPCR) and confocal microscopy analysis were used to determine the concentration and distribution of eDNA and intracellular DNA (iDNA). The mean amount of eDNA released by each species in the polymicrobial was higher than that in monospecies biofilms (S. aureus: 3.1 × 10[-2] ng/μl polymicrobial versus 5.1 × 10[-4] ng/μl monospecies; S. mutans: 3 × 10[-1] ng/μl polymicrobial versus 2.97 × 10[-2] ng/μl monospecies; C. albicans: 8.35 ng/μl polymicrobial versus 4.85 ng/μl monospecies). The large amounts of eDNA released by C. albicans (96%) in polymicrobial biofilms protects the S. aureus and S. mutans cells against the degradation by DNase I and dampens the effect of clindamycin.}, }
@article {pmid39486953, year = {2025}, author = {Li, Y and Sung Min, H and Chen, C and Shan, H and Lin, Y and Yin, F and Chen, Y and Lu, L and Yu, X}, title = {A chitosan/gelatin/aldehyde hyaluronic acid hydrogel coating releasing calcium ions and vancomycin in pH response to prevent the formation of bacterial biofilm.}, journal = {Carbohydrate polymers}, volume = {347}, number = {}, pages = {122723}, doi = {10.1016/j.carbpol.2024.122723}, pmid = {39486953}, issn = {1879-1344}, mesh = {*Biofilms/drug effects ; *Vancomycin/pharmacology/chemistry ; *Chitosan/chemistry/pharmacology/analogs &amp; derivatives ; *Hyaluronic Acid/chemistry/pharmacology ; *Gelatin/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; Hydrogen-Ion Concentration ; Animals ; *Hydrogels/chemistry/pharmacology ; Rats ; *Calcium/chemistry/metabolism ; *Staphylococcus aureus/drug effects ; Titanium/chemistry/pharmacology ; Rats, Sprague-Dawley ; Microbial Sensitivity Tests ; Drug Liberation ; Coated Materials, Biocompatible/chemistry/pharmacology ; }, abstract = {Osteomyelitis is a refractory disease of orthopedics, part of which is caused by medical implants. The main difficulties in treatment are the barrier effect after the formation of bacterial biofilm, and the difficulty in achieving sustained antibiotic intervention. In view of this situation, we studied a hydrogel coating that can release CaCl2 and vancomycin in pH-responsive manner. We used nano-TiO2 to modify Chitosan/ Gelatin/Aldehyde Hyaluronic Acid (CS/Gel/AHA) hydrogel, and combined with the dip-coating technique, prepared a coating with good mechanical strength. The hydrogel-loaded zeolitic imidazolate framework (ZIF) decomposes under acidic conditions, and the released Ca[2+] act on the bacterial Bap protein to inhibit the formation of biofilm, and the released vancomycin kills free bacteria. The antibacterial coating achieved good bactericidal effect in both in vitro experiments and rat subcutaneous implant model. These results not only provide a new way to enhance the strength of hydrogels to prepare coatings, but also utilize a new approach to responsively inhibit the formation of biofilms, showing the promising application prospects of the coating in antibacterial treatment of medical implants.}, }
@article {pmid39486481, year = {2024}, author = {Ivers, C and Chalamalasetti, S and Ruiz-Llacsahuanga, B and Critzer, F and Bhullar, M and Nwadike, L and Yucel, U and Trinetta, V}, title = {Evaluation of Commercially Available Sanitizers Efficacy to Control Salmonella (Sessile and Biofilm Forms) on Harvesting Bins and Picking Bags.}, journal = {Journal of food protection}, volume = {87}, number = {12}, pages = {100394}, doi = {10.1016/j.jfp.2024.100394}, pmid = {39486481}, issn = {1944-9097}, mesh = {*Biofilms/drug effects ; *Salmonella/drug effects ; *Disinfectants/pharmacology ; *Colony Count, Microbial ; Humans ; Food Microbiology ; Food Contamination/prevention &amp; control ; Chlorine Compounds/pharmacology ; Peracetic Acid/pharmacology ; Consumer Product Safety ; Oxides/pharmacology ; }, abstract = {This study evaluated the efficacy of five commercially available sanitizers to reduce Salmonella (sessile and biofilm forms) count on experimentally inoculated materials representative of harvesting bins and picking bags in the fresh produce industry. Sessile Salmonella cells were grown onto tryptic soy agar to create a bacterial lawn, while multistrain Salmonella biofilms were grown in a Centers for Disease Control and Prevention (CDC) reactor at 22 ± 2 °C for 96 h. Samples were exposed to 500 ppm free chlorine, 500 ppm peroxyacetic acid (PAA), 75 psi steam, and 5% silver dihydrogen citrate (SDC) for 30 sec, 1, or 2 min or 100 ppm chlorine dioxide gas for 24 h. Sanitizer, surface type, and application time significantly affected the viability of Salmonella in both sessile and biofilm forms (P < 0.05). All treatments resulted in a significant reduction of Salmonella when compared to the control (P < 0.05). Chlorine dioxide gas was the most effective treatment in both sessile and biofilm forms regardless of the type of surface, and it achieved a 5-log reduction. PAA at 500 ppm applied for 2 min was the only liquid sanitizer that resulted in a greater than 3-log reduction in all surfaces. Scanning electronic microscopy demonstrated the porous surface nature of nylon and wood, compared to HDPE, impacted sanitizer antimicrobial activity. Understanding the efficacy of sanitizers to control Salmonella on harvesting bins and picking bags may improve the safety of fresh produce by increasing available sanitizing treatment.}, }
@article {pmid39486468, year = {2024}, author = {Wu, W and Ni, S and Zheng, Y and Zhang, P and Jiang, Y and Li, X and Yu, Y and Qu, T}, title = {Hypervirulent carbapenem-susceptible klebsiella pneumoniae ST412/K57 with strong biofilm formation: association with gas gangrene and sepsis.}, journal = {International journal of antimicrobial agents}, volume = {64}, number = {6}, pages = {107373}, doi = {10.1016/j.ijantimicag.2024.107373}, pmid = {39486468}, issn = {1872-7913}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Klebsiella pneumoniae/drug effects/genetics/pathogenicity ; Animals ; Humans ; *Anti-Bacterial Agents/pharmacology/therapeutic use ; *Klebsiella Infections/microbiology/drug therapy ; *Mice, Inbred BALB C ; *Sepsis/microbiology/drug therapy ; *Carbapenems/pharmacology ; *Microbial Sensitivity Tests ; Mice ; Virulence ; Meropenem/pharmacology/therapeutic use ; Male ; Whole Genome Sequencing ; Moths/microbiology ; Female ; Disease Models, Animal ; }, abstract = {Hypervirulent Klebsiella pneumoniae (hvKp) poses a serious public health threat. Gas gangrene caused by hvKp is rarely reported and potentially results in a poor prognosis. This study describes the case of a hospitalised patient with gas gangrene and sepsis caused by hvKP. Carbapenem-susceptible hypervirulent Klebsiella pneumoniae (CS-hvKp) strains KPLSN and KPLSX were isolated from the knee joint pus and blood specimens of the patient for further investigations. Whole genome sequencing revealed that KPLSN and KPLSX were highly homologous (single nucleotide polymorphisms [SNPs]<10) and belonged to ST412/K57. The minimum inhibitory concentration and minimum bactericidal concentration under biofilm values of meropenem in KPLSN and KPLSX were significantly higher than in the planktonic state (>128 mg/L vs. 0.25 mg/L, P<0.0001). These two strains had high biofilm formation ability, and the results from fluorescence staining experiments showed that they were not easily killed by meropenem in the biofilm state. KPLSN and KPLSX showed high capsule production and were confirmed to have high virulence through experiments with the Galleria mellonella infection model and the BALB/c mice abdominal infection model. The persistent symptoms may be due to enhanced biofilm and capsule formation. Phylogenetic analysis of global ST412 strains showed their evolution towards higher virulence and resistance. These results emphasise the critical need for judicious antibiotic use and novel therapeutic approaches to combat special infections caused by these pathogens.}, }
@article {pmid39485542, year = {2024}, author = {Khodavandi, P and Soogh, MM and Alizadeh, F and Khodavandi, A and Nouripour-Sisakht, S}, title = {Menthol as an effective inhibitor of quorum sensing and biofilm formation in Candida albicans and Candida glabrata by targeting the transcriptional repressor TUP1.}, journal = {Molecular biology reports}, volume = {51}, number = {1}, pages = {1114}, pmid = {39485542}, issn = {1573-4978}, mesh = {*Biofilms/drug effects ; *Candida albicans/drug effects/pathogenicity/genetics ; *Quorum Sensing/drug effects ; *Candida glabrata/drug effects/pathogenicity/genetics ; *Menthol/pharmacology ; *Antifungal Agents/pharmacology ; *Reactive Oxygen Species/metabolism ; *Fungal Proteins/metabolism/genetics ; Repressor Proteins/metabolism/genetics ; Gene Expression Regulation, Fungal/drug effects ; Virulence Factors/genetics/metabolism ; Microbial Sensitivity Tests ; }, abstract = {BACKGROUND: Menthol, a natural quorum sensing molecule, is derived from the Mentha species. Combating pathogenicity by inactivating quorum sensing is an emerging approach. Therefore, our objective was to investigate anti-quorum sensing and anti-biofilm potentials of menthol in Candida albicans and Candida glabrata.<br><br>METHODS: The antifungal properties of menthol were evaluated using a broth microdilution assay and a time-kill assay, and its effects on quorum sensing-mediated virulence factors, cellular reactive oxygen species (ROS), and biofilm formation were tested by evaluating TUP1 expression levels in both C. albicans and C. glabrata.<br><br>RESULTS: Quorum sensing-mediated virulence factors and biofilm formation were inhibited by menthol in both C. albicans and C. glabrata. Furthermore, coinciding with elevated ROS levels, mRNAs of the quorum sensing-related gene TUP1 were upregulated in both C. albicans and C. glabrata.<br><br>CONCLUSIONS: This study highlights the anti-quorum sensing potential of menthol through the inhibition of quorum sensing-mediated virulence factors, ROS generation, and biofilm development by targeting TUP1, which could have potential in the treatment of Candida infections.}, }
@article {pmid39481715, year = {2024}, author = {Huang, J and Feng, X and Zhao, Y and Yi, B and Li, W and Zeng, X and Xu, H}, title = {Coral-like AgNPs hybrided MOFs modulated with biopolymer polydopamine for synergistic antibacterial and biofilm eradication.}, journal = {International journal of biological macromolecules}, volume = {282}, number = {Pt 5}, pages = {137080}, doi = {10.1016/j.ijbiomac.2024.137080}, pmid = {39481715}, issn = {1879-0003}, mesh = {*Indoles/chemistry/pharmacology ; *Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Polymers/chemistry/pharmacology ; *Silver/chemistry/pharmacology ; *Metal Nanoparticles/chemistry ; *Metal-Organic Frameworks/chemistry/pharmacology ; Staphylococcus aureus/drug effects ; Microbial Sensitivity Tests ; Biopolymers/chemistry/pharmacology ; Animals ; Reactive Oxygen Species/metabolism ; Escherichia coli/drug effects ; }, abstract = {Bacterial contamination is an intractable challenge in food safety, environments and biomedicine fields, and places a heavy burden on society. Polydopamine (PDA), a high molecular biopolymer, is considered as a promising candidate to participate in the design of novel antibacterial agents with unique contributions in biocompatibility, adherence, photothermal and metal coordination ability. In this study, coral-like ZIFL-PDA@AgNPs with excellent antibacterial properties and biocompatibility were prepared by embedding AgNPs into the biopolymer PDA-modulated ZIFL-PDA nanostructures by green reduction method to solve the problem with poor stability of AgNPs. Based on the plasma resonance effect of AgNPs, coral-like ZIFL-PDA@AgNPs had enhanced photothermal properties compared with ZIFL-PDA. Due to the synergistic effect between antibacterial metal ions mainly Ag[+] and the photothermal effect, coral-like ZIFL-PDA@AgNPs showed enhanced anti-mature biofilm and antibacterial properties, which was dependent on its concentration and sterilization time. In addition, regulated by the ZIFL-PDA nanostructure, coral-like ZIFL-PDA@AgNPs demonstrated a unique Ag[+] long-time sustained release behavior, giving it an extended antibacterial validity period and good biocompatibility. Antibacterial mechanism experiments indicated that coral-like ZIFL-PDA@AgNPs can significantly damage the integrity of bacterial cell membrane, reduce the content of ATP in bacterial by affecting the activity of succinate dehydrogenase, and induce the accumulation of reactive oxygen species, ultimately leading to bacterial death.}, }
@article {pmid39481691, year = {2024}, author = {Dhayalan, A and Prajapati, A and Yogisharadhya, R and Chanda, MM and Shivachandra, SB}, title = {Anti-quorum sensing and anti-biofilm activities of Pasteurella multocida strains.}, journal = {Microbial pathogenesis}, volume = {197}, number = {}, pages = {107085}, doi = {10.1016/j.micpath.2024.107085}, pmid = {39481691}, issn = {1096-1208}, mesh = {*Pasteurella multocida/drug effects/genetics ; *Biofilms/drug effects/growth &amp; development ; *Quorum Sensing/drug effects ; *Molecular Docking Simulation ; *Chromobacterium/drug effects/physiology/genetics ; Bacterial Proteins/genetics/metabolism ; beta-Lactamases/metabolism/genetics ; Animals ; Serogroup ; Bacterial Outer Membrane Proteins/genetics/metabolism ; Pasteurella Infections/microbiology/veterinary ; Whole Genome Sequencing ; Anti-Bacterial Agents/pharmacology ; Escherichia coli/drug effects/genetics ; }, abstract = {A total of 52 Pasteurella multocida strains of capsular serogroups (A, B and D) were screened for anti-quorum sensing activity against Chromobacterium violaceum. Of which, 12 strains of serogroups A were found to possess anti-quorum sensing activity. Inhibition activity was highest for strain NIVEDIPm9 and lowest for strain NIVEDIPm30 based on zone of pigment inhibition. Further, cell free extract of NIVEDIPm9 strain showed highest anti-biofilm activity in reference E. coli strain and concentration dependent degradation activity of C6-AHL molecule. In whole genome sequence annotation of NIVEDIPm9 strain predicted the presence of four metallo-β-lactamases (MBL) fold metallo-hydrolase proteins. In docking studies, MBL1 and MBL3 proteins showed high binding affinity with autoinduce signalling molecules AHL compound of OH-C10, binding energy value were -6.3 and -6.2 kcal/mol. Interaction study of VAF and quorum sensing molecules showed that OmpA and HgbA proteins were stimulated by all the ten molecules (C4-AHLs, C6-AHLs, C10-AHLs, C14-AHLs, 3-oxo-C10-AHLs, 3OH-C10-HSL, C8-HSL, C10-HSL, C12-HSL, C14-HSL), while toxA gene was stimulated by OH-C10-AHL molecule, sodC gene was stimulated by none. In conclusion, we described the anti-quorum sensing activities of diverse P. multocida strains causing Pasteurellosis in livestock.}, }
@article {pmid39481332, year = {2025}, author = {Yao, M and Ren, A and Yang, X and Chen, L and Wang, X and van der Meer, W and van Loosdrecht, MCM and Liu, G and Pabst, M}, title = {Unveiling the influence of heating temperature on biofilm formation in shower hoses through multi-omics.}, journal = {Water research}, volume = {268}, number = {Pt B}, pages = {122704}, doi = {10.1016/j.watres.2024.122704}, pmid = {39481332}, issn = {1879-2448}, mesh = {*Biofilms ; Proteomics ; Heating ; Metagenomics ; Hot Temperature ; Metagenome ; Multiomics ; }, abstract = {Shower systems provide unique environments that are conducive to biofilm formation and the proliferation of pathogens. The water heating temperature is a delicate decision that can impact microbial growth, balancing safety and energy consumption. This study investigated the impact of different heating temperatures (39 °C, 45 °C, 51 °C and 58 °C) on the shower hose biofilm (exposed to a final water temperature of 39 °C) using controlled full-scale shower setups. Whole metagenome sequencing and metaproteomics were employed to unveil the microbial composition and protein expression profiles. Overall, the genes and enzymes associated with disinfectant resistance and biofilm formation appeared largely unaffected. However, metagenomic analysis revealed a sharp decline in the number of total (86,371 to 34,550) and unique genes (32,279 to 137) with the increase in hot water temperature, indicating a significant reduction of overall microbial complexity. None of the unique proteins were detected in the proteomics experiments, suggesting smaller variation among biofilms on the proteome level compared to genomic data. Furthermore, out of 43 pathogens detected by metagenomics, only 5 could actually be detected by metaproteomics. Most interestingly, our study indicates that 45 °C heating temperature may represent an optimal balance. It minimizes active biomass (ATP) and reduces the presence of pathogens while saving heating energy. Our study offered new insights into the impact of heating temperature on shower hose biofilm formation and proposed optimal parameters that ensure biosafety while conserving energy.}, }
@article {pmid39479686, year = {2024}, author = {Ghahari, A and Khosravi-Darani, K}, title = {Hurdle technology using enzymes and essential oil to remove biofilm and increase the effectiveness of this process with the microencapsulation method.}, journal = {Food science &amp; nutrition}, volume = {12}, number = {10}, pages = {8483-8492}, pmid = {39479686}, issn = {2048-7177}, abstract = {The formation of biofilm in different places and the failure to effectively remove it by the usual disinfection methods is due to its structure and the rich genetic resource available in it to deal with disinfectants. These impenetrable structures and diverse microbial genetics have caused biofilm pollution in different industries like the food industry, the medicine industry, the hospitals and the water distribution system, resulting in pathogenicity and reduction of industrial quality. An efficient way to deal with the resistant population of biofilm-forming microbes is the use of hurdle technology including enzymes and essential oils. Enzymes reduce the resistance of the biofilm structure due to degradation of its extracellular polymer matrix (EPS) by their abilities to break down the organic molecules, and then the essential oils weaken the cells by penetrating the lipid membrane of the cell and destroying its integrity; as a result, the biofilm will be destroyed. The advantage of this hurdle technology is the environmental friendly of both methods, which reduces concerns about the use of chemical disinfection methods, but on the other hand, due to the sensitivity of enzymes as biological agents also the expensiveness of this technique and the considerations of working with essential oils as volatile and unstable liquids should abandon the routine methods of applying this disinfectant to biofilm and go for the microencapsulation method, which as a protective system increases the effectiveness of enzymes and essential oils as antibiofilm agents.}, }
@article {pmid39479282, year = {2024}, author = {Sultan, M and Arya, R and Chaurasia, AK and Kim, KK}, title = {Corrigendum: Sensor histidine kinases kdpD and aauS regulate biofilm and virulence in Pseudomonas aeruginosa PA14.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1501233}, doi = {10.3389/fcimb.2024.1501233}, pmid = {39479282}, issn = {2235-2988}, abstract = {[This corrects the article DOI: 10.3389/fcimb.2023.1270667.].}, }
@article {pmid39477005, year = {2024}, author = {Zhao, J and Xie, X and Chen, Z and Wang, Q and Zhang, H and Shen, Y and Ye, J and Zhang, S and Wu, C and Feng, K}, title = {Electro-stimulated biodegradation of dimethyl disulfide: Insights from biofilm spatial structure and key functional genes.}, journal = {Environmental pollution (Barking, Essex : 1987)}, volume = {363}, number = {Pt 2}, pages = {125216}, doi = {10.1016/j.envpol.2024.125216}, pmid = {39477005}, issn = {1873-6424}, mesh = {*Biofilms ; *Disulfides/chemistry ; *Biodegradation, Environmental ; Nanotubes, Carbon/chemistry ; Graphite/chemistry ; Electrodes ; Aniline Compounds/chemistry ; Oxidation-Reduction ; }, abstract = {As a typical sulfur-containing volatile organic compound, dimethyl disulfide (DMDS) is known for its high toxicity and resistance to degradation, necessitating efficient control in environmental media. To address the limitations of biological treatment in degradation capacity, this study employs electro-stimulation to promote DMDS elimination by a porous polyaniline@carbon nanotube bioanode developed on graphite sheet (PANI@CNT/GS). Compared with the unmodified GS bioanode, the PANI@CNT/GS bioanode demonstrates significant advantages in biofilm activity, redox property, and DMDS degradation efficiency. Kinetics analysis shows that the maximum degradation rate of the PANI@CNT/GS bioanode was 0.60 mM h[-1], which is 1.36 times higher than that of the control. Characterization results reveal that the highly active biofilms in PANI@CNT/GS bioanode possess 1.40 times the amount of living cells and a 12.5% increase in thickness, contributing to the notable enhancement in DMDS degradation capacity. Additionally, functional gene annotation indicates that the PANI@CNT/GS electrode facilitates the motility and activity of microbial cells and enriches the genes encoding key enzymes involved in DMDS metabolism. This work validates the feasibility of electro-stimulation for enhancing DMDS degradation and further provides in-depth insights into the process intensification mechanism from the perspectives of biofilm spatial structure and key functional genes.}, }
@article {pmid39476781, year = {2025}, author = {Li, L and Su, L and Gao, J and Liu, S and Yuan, S and Zhou, N and Zhou, Z and Wang, D and Zhou, Y and Dai, X}, title = {Enhanced biofilm-dependent biogas upgrading from waste activated sludge fermentation liquor in microbial electrolysis cells.}, journal = {Water research}, volume = {268}, number = {Pt A}, pages = {122675}, doi = {10.1016/j.watres.2024.122675}, pmid = {39476781}, issn = {1879-2448}, mesh = {*Biofilms ; *Sewage/microbiology ; *Biofuels ; *Fermentation ; Methane/metabolism ; Electrolysis ; Waste Disposal, Fluid/methods ; Bioreactors ; Electrodes ; Anaerobiosis ; }, abstract = {This study demonstrated that metal-organic frameworks (MOFs)-derived Fe-NC cathode improved both methane yield and methane content in a microbial electrolysis cell-coupled anaerobic digestion (MEC-AD) system treating waste activated sludge (WAS) fermentation liquor. Results revealed that Fe-NC maintained a meso‑macroporous structure with a large specific surface area of 1381 m[2]/g and superior electrochemical properties. Its calculated specific capacitance and electron transfer resistance were 5.7 and 0.4 times of the carbon felt (CF) group. The bacterial and archaeal gene loads of Fe-NC biofilm after multiple acclimation cycles were 5.69E+10 and 1.86E+9 copies/cm[2] and Proteiniphilum and Methanobacterium were the most enriched syntrophs from stage Ⅰ to stage Ⅱ acclimation. Corresponding maximum methane yield and content achieved were 0.31 m[3] CH4/kg COD and 92.8 %, and its CO2-dependent methane production was improved by 107.6 %. Mechanistic investigations showed that Fe-NC biofilm improved enzyme-associated CO2 reduction pathway companying by promoting the intra- and extracellular electron transfer as well as ATP synthesis, therefore favoring methanogenic energetic metabolism. More importantly, an enhanced proton-coupled electron transfer (PCET) process was proposed within Fe-NC biofilm, providing a synergistic advantage over unbalanced conventional sole electron/proton transfer. This work provides an effective strategy to strengthen the waste-to-energy and biogas upgrading technology, potentially bringing economic benefits to wastewater treatment.}, }
@article {pmid39476276, year = {2024}, author = {Gopalakrishnan, V and Saravanan, V and Mahendran, MIMS and Kumar, MPN}, title = {Helicobacter pylori biofilm interference by N-acyl homoserine lactonases: in vitro and in silico approaches.}, journal = {Molecular biology reports}, volume = {51}, number = {1}, pages = {1106}, pmid = {39476276}, issn = {1573-4978}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Helicobacter pylori/drug effects/enzymology ; *Bacterial Proteins/metabolism/chemistry ; *Carboxylic Ester Hydrolases/metabolism/chemistry ; Molecular Docking Simulation ; Quorum Sensing/drug effects ; Computer Simulation ; Bacillus licheniformis/enzymology ; Virulence Factors/metabolism ; }, abstract = {BACKGROUND: Qurom quenching enzyme have an impact on treatment efficacy and prevent the recurrence of Helicobacter pylori biofilm-related infections, although it has not been thoroughly investigated in vitro and in silico. The current study aims to characterize the N-acyl homoserine lactonase, the quorum quenching AiiA protein of Bacillus licheniformis against H. pylori biofilm.<br><br>METHODS AND RESULTS: In this study, AiiA protein were screened for their anti-biofilm activity, was found to effectively control biofilm formation of H. pylori with concentrations ranging from 2 to 10&#xa0;&#xb5;g/mL. According to CLSM and COMSTAT analysis, the untreated substratum had the robust biofilm biomass of 25-18 &#xb5;M and biovolume of 3-4 mm[3] /mm[2]. The total biofilm biovolume and average biofilm thickness were considerably reduced by 40% with a single application of 10&#xa0;&#xb5;g/mL of AiiA protein. The biofilm treated with AiiA exhibited a lower urease and polysaccharides than to the untreated biofilm. Further, in silico analysis, exhibited a greater interaction of AiiA against the outer membrane proteins of H. pylori compared to virulence factors. The conserved domains in the binding pockets of AiiA proteins showed a highest binding affinity proving the catalytic activity of the protein.<br><br>CONCLUSION: In this study, the H. pylori biofilm architecture, exopolysaccharide and urease were significantly controlled by our purified N-acyl homoserine lactonase from B. licheniformis. Furthermore, the molecular docking showed the significant interaction between AiiA and key biofilm forming and virulence proteins proved an excellent antibiofilm activity controlling the infections of H. pylori human pathogen.}, }
@article {pmid39476249, year = {2024}, author = {Driche, EH and Badji, B and Mathieu, F and Zitouni, A}, title = {In-vitro antibacterial and antibiofilm activities and in-silico analysis of a potent cyclic peptide from a novel Streptomyces sp. strain RG-5 against antibiotic-resistant and biofilm-forming pathogenic bacteria.}, journal = {Archives of microbiology}, volume = {206}, number = {11}, pages = {450}, pmid = {39476249}, issn = {1432-072X}, mesh = {*Streptomyces/chemistry/isolation &amp; purification/genetics ; *Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry/isolation &amp; purification ; *Peptides, Cyclic/pharmacology/chemistry/isolation &amp; purification ; *Microbial Sensitivity Tests ; *Molecular Docking Simulation ; *Soil Microbiology ; RNA, Ribosomal, 16S/genetics ; Phylogeny ; Drug Resistance, Multiple, Bacterial/drug effects ; Bacteria/drug effects ; }, abstract = {The proliferation of multidrug-resistant and biofilm-forming pathogenic bacteria poses a serious threat to public health. The limited effectiveness of current antibiotics motivates the search for new antibacterial compounds. In this study, a novel strain, RG-5, was isolated from desert soil. This strain exhibited potent antibacterial and antibiofilm properties against multidrug-resistant and biofilm-forming pathogenic bacteria. Through phenotypical characterizations, 16S rRNA gene sequence and phylogenetic analysis, the strain was identified as Streptomyces pratensis with 99.8% similarity. The active compound, RG5-1, was extracted, purified by reverse phase silica column HPLC, identified by ESI-MS spectrometry, and confirmed by [1]H and [13]C NMR analysis as 2,5-Piperazinedione, 3,6-bis(2-methylpropyl), belonging to cyclic peptides. This compound showed interesting minimum inhibitory concentrations (MICs) of 04 to 15 µg/mL and minimum biofilm inhibitory concentrations (MBICs 50%) of ½ MIC against the tested bacteria. Its molecular mechanism of action was elucidated through a molecular docking study against five drug-protein targets. The results demonstrated that the compound RG5-1 has a strong affinity and interaction patterns with glucosamine-6-phosphate synthase at - 6.0 kcal/mol compared to reference inhibitor (- 5.4 kcal/mol), medium with penicillin-binding protein 1a (- 6.1 kcal/mol), and LasR regulator protein of quorum sensing (- 5.4 kcal/mol), confirming its antibacterial and antibiofilm activities. The compound exhibited minimal toxicity and favorable physicochemical and pharmacological properties. This is the first report that describes its production from Streptomyces, its activities against biofilm-forming and multidrug-resistant bacteria, and its mechanism of action. These findings indicate that 2,5-piperazinedione, 3,6-bis(2-methylpropyl) has the potential to be a promising lead compound in the treatment of antibiotic-resistant and biofilm-forming pathogens.}, }
@article {pmid39475232, year = {2024}, author = {Hunt, BC and Brix, V and Vath, J and Guterman, LB and Taddei, SM and Deka, N and Learman, BS and Brauer, AL and Shen, S and Qu, J and Armbruster, CE}, title = {Metabolic interplay between Proteus mirabilis and Enterococcus faecalis facilitates polymicrobial biofilm formation and invasive disease.}, journal = {mBio}, volume = {15}, number = {12}, pages = {e0216424}, pmid = {39475232}, issn = {2150-7511}, support = {F30 DK136213/DK/NIDDK NIH HHS/United States ; R01DK123158//HHS | NIH | National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)/ ; P30 DK050306/DK/NIDDK NIH HHS/United States ; R01 DK123158/DK/NIDDK NIH HHS/United States ; F31 AI183838/AI/NIAID NIH HHS/United States ; F32AI183755//HHS | NIH | National Institute of Allergy and Infectious Diseases (NIAID)/ ; P30DK050306/DK/NIDDK NIH HHS/United States ; F32 AI183755/AI/NIAID NIH HHS/United States ; F31AI183838//HHS | NIH | National Institute of Allergy and Infectious Diseases (NIAID)/ ; }, mesh = {*Biofilms/growth &amp; development/drug effects ; *Proteus mirabilis/physiology/drug effects/metabolism ; *Enterococcus faecalis/physiology/metabolism/growth &amp; development/drug effects ; Animals ; Mice ; *Urinary Tract Infections/microbiology ; Ornithine/metabolism/analogs &amp; derivatives/pharmacology ; Catheter-Related Infections/microbiology ; Coinfection/microbiology ; Arginine/metabolism ; Gram-Positive Bacterial Infections/microbiology ; Proteus Infections/microbiology ; Microbial Interactions ; Female ; Disease Models, Animal ; Humans ; }, abstract = {Biofilms play an important role in the development and pathogenesis of catheter-associated urinary tract infection (CAUTI). Proteus mirabilis and Enterococcus faecalis are common CAUTI pathogens that persistently co-colonize the catheterized urinary tract and form biofilms with increased biomass and antibiotic resistance. In this study, we uncover the metabolic interplay that drives biofilm enhancement and examine the contribution to CAUTI severity. Through compositional and proteomic biofilm analyses, we determined that the increase in biofilm biomass stems from an increase in the protein fraction of the polymicrobial biofilm. We further observed an enrichment in proteins associated with ornithine and arginine metabolism in polymicrobial biofilms compared with single-species biofilms. We show that arginine/ornithine antiport by E. faecalis promotes arginine biosynthesis and metabolism in P. mirabilis, ultimately driving the increase in polymicrobial biofilm protein content without affecting viability of either species. We further show that disrupting E. faecalis ornithine antiport alters the metabolic profile of polymicrobial biofilms and prevents enhancement, and this defect was complemented by supplementation with exogenous ornithine. In a murine model of CAUTI, ornithine antiport did not contribute to E. faecalis colonization but was required for the increased incidence of urinary stone formation and bacteremia that occurs during polymicrobial CAUTI with P. mirabilis. Thus, disrupting metabolic interplay between common co-colonizing species may represent a viable strategy for reducing risk of bacteremia.IMPORTANCEChronic infections often involve the formation of antibiotic-resistant biofilm communities that include multiple different microbes, which pose a challenge for effective treatment. In the catheterized urinary tract, potential pathogens persistently co-colonize for long periods of time and the interactions between them can lead to more severe disease outcomes. In this study, we identified the metabolite L-ornithine as a key mediator of disease-enhancing interactions between two common and challenging pathogens, Enterococcus faecalis and Proteus mirabilis. Disrupting ornithine-mediated interactions may therefore represent a strategy to prevent polymicrobial biofilm formation and decrease risk of severe disease.}, }
@article {pmid39473923, year = {2024}, author = {Li, Y and Huang, S and Du, J and Wang, S and Cai, Z and Huang, X}, title = {Deciphering the killing mechanisms of potassium iodide in combination with antimicrobial photodynamic therapy against cross-kingdom biofilm.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1444764}, pmid = {39473923}, issn = {2235-2988}, mesh = {*Biofilms/drug effects ; *Potassium Iodide/pharmacology ; Humans ; *Photochemotherapy/methods ; *Candida albicans/drug effects ; *Streptococcus mutans/drug effects ; *Reactive Oxygen Species/metabolism ; *Tolonium Chloride/pharmacology ; Photosensitizing Agents/pharmacology ; Anti-Infective Agents/pharmacology ; Microbial Viability/drug effects ; Dental Caries/microbiology/drug therapy ; Apoptosis/drug effects ; Dentin/microbiology/drug effects ; }, abstract = {INTRODUCTION: The co-existence of S. mutans and C. albicans is frequently detected in root caries and early child caries and is reported to be associated with recurrent caries. The aim of this study was to investigate the effects of potassium iodide (KI) in combination with toluidine blue O-mediated antimicrobial photodynamic therapy (aPDT) on S. mutans and C. albicans mixed-species biofilm, as well as the antibiofilm mechanisms involved.<br><br>METHODS: Mixed-species biofilm was constructed of S. mutans and C. albicans on dentin blocks. The antibiofilm efficacy, cytotoxicity and antibiofilm mechanism of KI in combination with aPDT were determined and evaluated.<br><br>RESULTS: KI+TBO-aPDT treatment caused reduction in microorganism counts, metabolic activity, and biofilm biomass of mixed-species biofilm without inducing cytotoxicity to hDPCs (human dental pulp cells). Observations such increased ROS (reactive oxygen species) levels, impaired cell membrane function, cell apoptosis and reduced expression in several genes seem to be artifacts of reduced growth and general killing by KI+TBO-aPDT treatment.<br><br>DISCUSSION: These data suggested that KI in combination with aPDT as an innovative approach to combat S. mutans and C. albicans biofilm, and thus as an optional treatment for caries.}, }
@article {pmid39473843, year = {2024}, author = {Tang, D and Xi, Y and Song, W and Li, M and Liu, Y and Lin, Y and Zhang, R and Mao, A}, title = {Design and synthesis of quorum-sensing agonist for improving biofilm formation and the application of Acidithiobacillus thiooxidans in bioleaching.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1465633}, pmid = {39473843}, issn = {1664-302X}, abstract = {INTRODUCTION: Currently, there are few investigations on the effect of a synthetic exogenous quorum sensing (QS) agonist on the bioleaching rate of Acidithiobacillus thiooxidans (A. thiooxidans).<br><br>METHODS: We created AHL (N-acyl-homoserine lactone) analogues and investigated their effects on A. thiooxidans biofilm formation, adsorption kinetics, bioleaching, and mechanism.<br><br>RESULTS: The findings revealed that N-(3-thiolactone)- dodecylamine (Y3) significantly increased the biofilm formation of A. thiooxidans in 96-well plates and sulfur sheets. Adsorption tests revealed that Y3 increased the adhesion rate, adsorption constant, and adsorption efficiency. Bioleaching tests indicated that Y3 boosted bioleaching efficiency, with Ni[2+] and Cu[2+] bioleaching rates increasing by 49.13% and 33.03%, respectively. Transcriptomic analysis revealed that Y3 increased genes associated with QS pathways and biofilm formation, particularly afeI, which was dramatically elevated 42 times.<br><br>DISCUSSION: The study laid the groundwork for a better understanding of the mechanics of A. thiooxidans biofilm formation, which could help improve the potential application of A. thiooxidans in bioleaching.}, }
@article {pmid39472801, year = {2024}, author = {Valiei, A and Dickson, AM and Aminian-Dehkordi, J and Mofrad, MRK}, title = {Bacterial community dynamics as a result of growth-yield trade-off and multispecies metabolic interactions toward understanding the gut biofilm niche.}, journal = {BMC microbiology}, volume = {24}, number = {1}, pages = {441}, pmid = {39472801}, issn = {1471-2180}, mesh = {*Bacteria/metabolism/classification/growth &amp; development/genetics ; *Biofilms/growth &amp; development ; Humans ; *Gastrointestinal Microbiome ; Microbial Interactions ; Bacterial Physiological Phenomena ; Models, Biological ; Kinetics ; Symbiosis ; Ecosystem ; Nutrients/metabolism ; }, abstract = {Bacterial communities are ubiquitous, found in natural ecosystems, such as soil, and within living organisms, like the human microbiome. The dynamics of these communities in diverse environments depend on factors such as spatial features of the microbial niche, biochemical kinetics, and interactions among bacteria. Moreover, in many systems, bacterial communities are influenced by multiple physical mechanisms, such as mass transport and detachment forces. One example is gut mucosal communities, where dense, closely packed communities develop under the concurrent influence of nutrient transport from the lumen and fluid-mediated detachment of bacteria. In this study, we model a mucosal niche through a coupled agent-based and finite-volume modeling approach. This methodology enables us to model bacterial interactions affected by nutrient release from various sources while adjusting individual bacterial kinetics. We explored how the dispersion and abundance of bacteria are influenced by biochemical kinetics in different types of metabolic interactions, with a particular focus on the trade-off between growth rate and yield. Our findings demonstrate that in competitive scenarios, higher growth rates result in a larger share of the niche space. In contrast, growth yield plays a critical role in neutralism, commensalism, and mutualism interactions. When bacteria are introduced sequentially, they cause distinct spatiotemporal effects, such as deeper niche colonization in commensalism and mutualism scenarios driven by species intermixing effects, which are enhanced by high growth yields. Moreover, sub-ecosystem interactions dictate the dynamics of three-species communities, sometimes yielding unexpected outcomes. Competitive, fast-growing bacteria demonstrate robust colonization abilities, yet they face challenges in displacing established mutualistic systems. Bacteria that develop a cooperative relationship with existing species typically obtain niche residence, regardless of their growth rates, although higher growth yields significantly enhance their abundance. Our results underscore the importance of bacterial niche dynamics in shaping community properties and succession, highlighting a new approach to manipulating microbial systems.}, }
@article {pmid39472585, year = {2024}, author = {Li, Y and Cao, X and Chai, Y and Chen, R and Zhao, Y and Borriss, R and Ding, X and Wu, X and Ye, J and Hao, D and He, J and Wang, G and Cao, M and Jiang, C and Han, Z and Fan, B}, title = {A phosphate starvation induced small RNA promotes Bacillus biofilm formation.}, journal = {NPJ biofilms and microbiomes}, volume = {10}, number = {1}, pages = {115}, pmid = {39472585}, issn = {2055-5008}, support = {31970097//National Natural Science Foundation of China (National Science Foundation of China)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Gene Expression Regulation, Bacterial ; *Bacillus/genetics/physiology/metabolism ; *Phosphates/metabolism ; *Bacterial Proteins/genetics/metabolism ; *RNA, Bacterial/genetics ; RNA, Small Untranslated/genetics ; Operon ; Bacillus subtilis/genetics/physiology/metabolism ; }, abstract = {Currently, almost all known regulators involved in bacterial phosphorus metabolism are proteins. In this study, we identified a conserved new small regulatory RNA (sRNA), named PhoS, encoded in the 3' untranslated region (UTR) of the phoPR genes in Bacillus velezensis and B. subtilis. Expression of phoS is strongly induced upon phosphorus scarcity and stimulated by the transcription factor PhoP. Conversely, PhoS positively regulates PhoP translation by binding to the ribosome binding site (RBS) of phoP mRNA. PhoS can promote Bacillus biofilm formation through, at least in part, enhancing the expression of the matrix-related genes, such as the eps genes and the tapA-sipW-tasA operon. The positive regulation of phoP expression by PhoS contributes to the promoting effect of PhoS on biofilm formation. sRNAs regulating biofilm formation have rarely been reported in gram-positive Bacillus species. Here we highlight the significance of sRNAs involved in two important biological processes: phosphate metabolism and biofilm formation.}, }
@article {pmid39471904, year = {2025}, author = {Guo, X and Zhu, W and Wang, Z and Peng, G and Tan, L and Ming, T and Zhang, S and Zhang, S}, title = {Insight into shortening mechanisms of start-up time for three-dimensional biofilm electrode reactor/pyrite-autotrophic denitrification coupled system.}, journal = {Bioresource technology}, volume = {415}, number = {}, pages = {131719}, doi = {10.1016/j.biortech.2024.131719}, pmid = {39471904}, issn = {1873-2976}, mesh = {*Biofilms ; *Denitrification ; *Bioreactors ; *Electrodes ; *Sulfides/chemistry/metabolism ; *Iron/metabolism ; Nitrates/metabolism ; Autotrophic Processes ; Time Factors ; }, abstract = {In this study, a three-dimensional biofilm electrode reactor (3D-BER)/pyrite-autotrophic denitrification (PAD) coupled (3D-BER-PAD) system was constructed, aiming at investigating the effect of current on the start-up period of the system. The results showed that increasing current could shorten the system's start-up period and improve nitrate removal efficiency (NRE). When the current was 20 mA, the system could start stabilization after approximately 13 days and maintain a stable NRE (88.2 ± 3.4 %) with low energy consumption (0.05 ± 0.003 kW·h/gNO3[-]-N). Additionally, an appropriate current (10 or 20 mA) promoted the reproduction of denitrifying bacteria (e.g., Thiobacillus and Thermomonas) and the expression of functional genes involved in denitrification and sulfur oxidation. Finally, the denitrification mechanism and electron transfer model in the 3D-BER-PAD system were proposed. This study has reference value for the rapid start-up and the improvement of treatment efficiency in the 3D-BER-PAD system.}, }
@article {pmid39471596, year = {2024}, author = {Mkpuma, VO and Moheimani, NR and Ennaceri, H}, title = {Effect of light intensity on Chlorella sp. biofilm growth on anaerobically digested food effluents (ADFE).}, journal = {Journal of environmental management}, volume = {371}, number = {}, pages = {123015}, doi = {10.1016/j.jenvman.2024.123015}, pmid = {39471596}, issn = {1095-8630}, mesh = {*Chlorella/growth &amp; development/radiation effects/metabolism ; *Biofilms/growth &amp; development/radiation effects ; *Light ; *Biomass ; Anaerobiosis ; Microalgae/growth &amp; development/radiation effects/metabolism ; Nitrogen/metabolism ; Biological Oxygen Demand Analysis ; Waste Disposal, Fluid/methods ; Food ; }, abstract = {Optimizing light conditions in any culture design for effluent treatment is crucial for maximizing microalgae growth and nutrient uptake. We investigated the impact of low (53 ± 1 μmol m[-2] s[-1]), medium (208 ± 12 μmol m[-2] s[-1]), and high (518 ± 22 μmol m[-2] s[-1]) light intensities on the diffused biofilm-based growth of Chlorella sp. for treating anaerobically digested food effluent (ADFE). The alga grew well across all treatments, irrespective of light intensity. However, biomass yields, and productivity positively correlated with light intensity, with the highest biomass yield (120 g m[-2]) and productivity (11.6 g m[-2] d[-1]) occurring at high light intensity. Notably, specific growth rates peaked uniformly on day 2 across all treatments, indicating an initial surge in growth. A relatively stable photosynthetic performance occurred under medium light treatment, while stress evidence was noticed particularly after day 4 at high and low light treatments, with higher magnitude seen under low light treatments. Total ammonia nitrogen (TAN) and phosphate removal efficiencies increased with light intensities, reaching 100 % removal at high light after 10 days. Intriguingly, there was a notable enhancement in chemical oxygen demand (COD) removal under low light conditions, being 2.9- and 1.64-fold higher compared to medium and high light intensities, respectively. Despite the superior performance of Chlorella sp. biofilm under high-light conditions in biomass yield and uptake of nutrients, the low-light treatment also achieved remarkable results, indicating that this biofilm design offers enhanced exposure to light. Therefore, this biofilm configuration presents an enticing opportunity for treating ADFE at lower light intensities, potentially minimizing energy consumption while maximizing profitability.}, }
@article {pmid39471569, year = {2025}, author = {Wu, J and Huo, X and Liu, J and Bu, F and Zhang, P}, title = {Multifunctional NIR-II nanoplatform for disrupting biofilm and promoting infected wound healing.}, journal = {Colloids and surfaces. B, Biointerfaces}, volume = {245}, number = {}, pages = {114330}, doi = {10.1016/j.colsurfb.2024.114330}, pmid = {39471569}, issn = {1873-4367}, mesh = {*Biofilms/drug effects ; *Wound Healing/drug effects ; *Methicillin-Resistant Staphylococcus aureus/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Infrared Rays ; *Microbial Sensitivity Tests ; Animals ; Nanoparticles/chemistry ; Photothermal Therapy ; Mice ; Particle Size ; Polymers/chemistry/pharmacology ; Surface Properties ; Wound Infection/drug therapy/microbiology ; Humans ; }, abstract = {Healing wounds presents a significant challenge due to bacterial biofilm infections and the inherent drug resistance of these biofilms. This report introduces a multifunctional nanoplatform (NPs) designed to combat wound biofilm infections using NIR-II photothermal therapy. The NPs are self-assembled from amphiphilic polymers (AP) to encapsulate photothermal polymers (PT) through classic electrostatic interactions. Importantly, these NPs are electrically neutral, which enhances their ability to penetrate biofilms effectively. Once inside the biofilm, the NPs achieve complete thermal ablation of the biofilm under NIR-II laser irradiation. Additionally, when exposed to laser and the GSH microenvironment, the NPs exhibit strong photothermal effects and self-degradation capabilities. In vitro tests confirm that the NPs have excellent antibacterial and anti-biofilm properties against methicillin-resistant Staphylococcus aureus (MRSA). In vivo studies demonstrate that the NPs can efficiently clear wound biofilm infections and promote wound healing. Notably, the NPs show superior photothermal effects under NIR-II laser irradiation compared to NIR-I lasers. In summary, the developed NPs serve as an integrated diagnostic and therapeutic nano-antimicrobial agent, offering promising applications for biofilm wound infections and wound healing.}, }
@article {pmid39470274, year = {2024}, author = {Sivori, F and Cavallo, I and Truglio, M and Pelagalli, L and Mariani, V and Fabrizio, G and Abril, E and Santino, I and Fradiani, PA and Solmone, M and Pimpinelli, F and Toma, L and Arcioni, R and De Blasi, RA and Di Domenico, EG}, title = {Biofilm-mediated antibiotic tolerance in Staphylococcus aureus from spinal cord stimulation device-related infections.}, journal = {Microbiology spectrum}, volume = {12}, number = {12}, pages = {e0168324}, pmid = {39470274}, issn = {2165-0497}, abstract = {Staphylococcus aureus is a predominant cause of infections in individuals with spinal cord stimulation (SCS) devices. Biofilm formation complicates these infections, commonly requiring both surgical and antibiotic treatments. This study explored the biofilm matrix composition and antimicrobial susceptibility of planktonic and biofilm-growing S. aureus isolates from individuals with SCS-related infections. Whole-genome sequencing (WGS) examined genotypes, virulome, resistome, and the pan-genome structure. The study also analyzed biofilm matrix composition, early surface adhesion, hemolytic activity, and antibiotic-susceptibility testing. WGS revealed genetic diversity among isolates. One isolate, though oxacillin susceptible, contained the mecA gene. The median number of virulence factor genes per isolate was 58. All isolates harbored the biofilm-related icaA/D genes. When assessing phenotypic characteristics, all strains demonstrated the ability to form biofilms in vitro. The antimicrobial susceptibility profile indicated that oxacillin, rifampin, and teicoplanin showed the highest efficacy against S. aureus biofilm. Conversely, high biofilm tolerance was observed for vancomycin, trimethoprim/sulfamethoxazole, and levofloxacin. These findings suggest that S. aureus isolates are highly virulent and produce robust biofilms. In cases of suspected biofilm infections caused by S. aureus, vancomycin should not be the primary choice due to its low activity against biofilm. Instead, oxacillin, rifampin, and teicoplanin appear to be more effective options to manage SCS infections.IMPORTANCESCS devices are increasingly used to manage chronic pain, but infections associated with these devices, particularly those caused by Staphylococcus aureus, present significant clinical challenges. These infections are often complicated by biofilm formation, which protects bacteria from immune responses and antibiotic treatments, making them difficult to eradicate. Understanding the genetic diversity, virulence, and biofilm characteristics of S. aureus isolates from SCS infections is critical to improving treatment strategies. Our study highlights the need to reconsider commonly used antibiotics like vancomycin, which shows reduced activity against biofilm-growing cells. Identifying more effective alternatives, such as oxacillin, rifampin, and teicoplanin, provides valuable insight for clinicians when managing biofilm-related S. aureus infections in patients with SCS implants. This research contributes to the growing evidence that biofilm formation is crucial in treating device-related infections, emphasizing the importance of tailoring antimicrobial strategies to the biofilm phenotype.}, }
@article {pmid39470240, year = {2024}, author = {Dumann, G and Rohland, O and Abdel-Glil, MY and Allen, RJ and Bauer, M and Busch, A}, title = {Draft genomes of the bile duct microbiome strains Klebsiella pneumoniae and Enterococcus lactis isolated from bilioenteric drainages with biofilm-forming abilities.}, journal = {Microbiology resource announcements}, volume = {13}, number = {12}, pages = {e0020224}, pmid = {39470240}, issn = {2576-098X}, support = {EXC 2051 - Project-ID 390713860//Deutsche Forschungsgemeinschaft (DFG)/ ; }, abstract = {We describe the genetic properties of two strains isolated from the elusive bile duct microbiome from solid organ transplant patients. Bacterial strains Enterococcus lactis (MS-STENT-08-E-001) and Klebsiella pneumoniae (MS-STENT-01-M-001) were isolated from the biofilms of bile duct catheters.}, }
@article {pmid39470147, year = {2024}, author = {Shaik, MR and Ramasamy, M and Jain, D and Muthu, K and Marunganathan, V and Manivannan, C and Hussain, SA and Deepak, P and Thiyagarajulu, N and Guru, A and Venkatesan, D}, title = {Synergistic Action of Rutin-Coated Zinc Oxide Nanoparticles: Targeting Biofilm Formation Receptors of Dental Pathogens and Modulating Apoptosis Genes for Enhanced Oral Anticancer Activity.}, journal = {Journal of biochemical and molecular toxicology}, volume = {38}, number = {11}, pages = {e70030}, doi = {10.1002/jbt.70030}, pmid = {39470147}, issn = {1099-0461}, support = {//The authors acknowledge the funding from Researchers Supporting Project number (RSP2024R371), King Saud University, Riyadh, Saudi Arabia./ ; }, mesh = {*Zinc Oxide/pharmacology/chemistry ; Humans ; *Biofilms/drug effects ; *Apoptosis/drug effects ; *Rutin/pharmacology/chemistry ; *Antineoplastic Agents/pharmacology/chemistry ; Metal Nanoparticles/chemistry ; Candida albicans/drug effects ; Drug Synergism ; Cell Line, Tumor ; Antioxidants/pharmacology/chemistry ; Nanoparticles/chemistry ; Streptococcus mutans/drug effects ; Molecular Docking Simulation ; }, abstract = {Oral diseases are often associated with bacterial and fungal pathogens such as Staphylococcus aureus, Streptococcus mutans, Enterococcus faecalis, and Candida albicans. This research explored a novel approach to addressing these pathogens by synthesizing zinc oxide nanoparticles (ZnO NPs) coated with rutin (RT), a plant-derived compound. The synthesized ZnO-RT NPs were comprehensively characterized using UV-Vis spectrophotometer, SEM, and EDAX techniques to confirm their structural composition. The antioxidant potential was assessed through free radical scavenging assays. Additionally, the antimicrobial activity of ZnO-RT NPs was evaluated using a zone of inhibition assay against oral pathogens. Molecular docking studies with the Autodock tool were performed to elucidate the interactions between RT and the receptors of oral pathogens. The findings demonstrated that ZnO-RT NPs exhibited robust free radical scavenging activity. Furthermore, they showed significant antimicrobial activity with a minimal inhibitory concentration of 40 μg/mL against oral pathogens. ZnO-RT NPs also displayed dose-dependent anticancer effects on human oral cancer cells at concentrations of 10, 20, 40, and 80 μg/mL. Mechanistic insights into the anticancer activity on KB cells revealed the upregulation of apoptotic genes. This study underscores the promising potential of ZnO-RT NPs for dental applications due to their strong antioxidant, anticancer, and antimicrobial properties. These nanoparticles offer a hopeful prospect for addressing oral pathogen challenges and enhancing overall oral health.}, }
@article {pmid39469629, year = {2024}, author = {Krzyżek, P and Migdał, P and Tusiewicz, K and Zawadzki, M and Szpot, P}, title = {Subinhibitory concentrations of antibiotics affect development and parameters of Helicobacter pylori biofilm.}, journal = {Frontiers in pharmacology}, volume = {15}, number = {}, pages = {1477317}, pmid = {39469629}, issn = {1663-9812}, abstract = {INTRODUCTION: Helicobacter pylori causes chronic gastric diseases in nearly 50% of people around the world. It is suggested that biofilm formation has a pronounced effect on the dynamic resistance spread and recurrence of these infections.<br><br>METHODS: To mimic the scenario of therapeutic ineffectiveness, we investigated the impact of sub-minimal inhibitory concentrations (sub-MICs) of antibiotics on the development and parameters of biofilms produced by clinical H. pylori strains.<br><br>RESULTS: We observed that constant exposure of planktonic forms to metronidazole or levofloxacin stimulated the speed of autoaggregation and the amount of extracellular matrix, resulting in increased dimensions of the developed biofilms. Contrary to this, continuous exposure to clarithromycin negatively affected a number of biofilm-related reactions and led to the biofilm-weakening effect. Through assessing the membrane fatty acid profiles of antibiotic-exposed cells, we confirmed that metronidazole and levofloxacin induced a biofilm-like phenotype, while clarithromycin kept bacteria in a planktonic form.<br><br>DISCUSSION: Our results suggest that sub-MICs of antibiotics affect the biochemical and biophysical properties of the developing biofilm of H. pylori strains and may impact the effectiveness of antibiotic treatment.}, }
@article {pmid39469492, year = {2024}, author = {Thiers, I and Lissens, M and Langie, H and Lories, B and Steenackers, H}, title = {Salmonella biofilm formation diminishes bacterial proliferation in the C. elegans intestine.}, journal = {Biofilm}, volume = {8}, number = {}, pages = {100225}, pmid = {39469492}, issn = {2590-2075}, abstract = {Non-typhoidal Salmonella serovars are a significant global cause of foodborne infections, owing their transmission success to the formation of biofilms. While the role of these biofilms in Salmonella's persistence outside the host is well understood, their significance during infection remains elusive. In this study, we investigated the impact of Salmonella biofilm formation on host colonization and virulence using the nematode model Caenorhabditis elegans. This infection model enables us to isolate the effect of biofilm formation on gut colonization and proliferation, as no gut microbiome is present and Salmonella cannot invade the intestinal tissue of the nematode. We show that a biofilm-deficient ΔcsgD mutant enhances gut proliferation compared to the wild-type strain, while the pathogen's virulence, the host's immune signaling pathways, and host survival remain unaffected. Hence, our work suggests that biofilm formation does not significantly contribute to Salmonella infection in C. elegans. However, complementary assays in higher-order in vivo models are required to further characterize the role of biofilm formation during infection and to take into account the impact of biofilm formation on competition with gut microbiome and epithelial invasion.}, }
@article {pmid39469451, year = {2024}, author = {Judan Cruz, KG and Takumi, O and Bongulto, KA and Gandalera, EE and Kagia, N and Watanabe, K}, title = {Natural compound-induced downregulation of antimicrobial resistance and biofilm-linked genes in wastewater Aeromonas species.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1456700}, pmid = {39469451}, issn = {2235-2988}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Aeromonas/drug effects/genetics ; *Wastewater/microbiology ; *Drug Resistance, Bacterial/genetics ; Anti-Bacterial Agents/pharmacology ; Sewage/microbiology ; Down-Regulation ; Gene Expression Regulation, Bacterial/drug effects ; Genes, Bacterial/genetics ; Biological Products/pharmacology ; Microbial Sensitivity Tests ; Phytochemicals/pharmacology ; }, abstract = {Addressing the global antimicrobial resistance (AMR) crisis requires a multifaceted innovative approach to mitigate impacts on public health, healthcare and economic systems. In the complex evolution of AMR, biofilms and the acquisition of antimicrobial resistance genes (ARGs) play a pivotal role. Aeromonas is a major AMR player that often forms biofilm, harbors ARGs and is frequently detected in wastewater. Existing wastewater treatment plants (WWTPs) do not have the capacity to totally eliminate antimicrobial-resistant bacteria favoring the evolution of ARGs in wastewater. Besides facilitating the emergence of AMR, biofilms contribute significantly to biofouling process within the activated sludge of WWTP bioreactors. This paper presents the inhibition of biofilm formation, the expression of biofilm-linked genes and ARGs by phytochemicals andrographolide, docosanol, lanosterol, quercetin, rutin and thymohydroquinone. Aeromonas species were isolated and purified from activated sludge samples. The ARGs were detected in the isolated Aeromonas species through PCR. Aeromonas biofilms were quantified following the application of biocompounds through the microtiter plate assay. qPCR analyses of related genes were done for confirmation. Findings showed that the natural compounds inhibited the formation of biofilms and reduced the expression of genes linked to biofilm production as well as ARGs in wastewater Aeromonas. This indicates the efficacy of these compounds in targeting and controlling both ARGs and biofilm formation, highlighting their potential as innovative solutions for combating antimicrobial resistance and biofouling.}, }
@article {pmid39468094, year = {2024}, author = {Abdelraheem, WM and Kamel, HS and Gamil, AN}, title = {Evaluation of anti-biofilm and anti-virulence effect of zinc sulfate on Staphylococcus aureus isolates.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {25747}, pmid = {39468094}, issn = {2045-2322}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Staphylococcus aureus/drug effects/pathogenicity ; *Zinc Sulfate/pharmacology ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; Virulence/drug effects ; Virulence Factors/genetics ; Humans ; Staphylococcal Infections/microbiology/drug therapy ; Hemolysis/drug effects ; Drug Synergism ; Gene Expression Regulation, Bacterial/drug effects ; }, abstract = {Staphylococcus aureus produces a plethora of virulence factors to invade and establish infections in the host system, and biofilms are more resistant to antibiotics than planktonic cells. In this study, we aimed to investigate the anti-virulence and anti-biofilm potentials of zinc sulfate against S. aureus isolates. The synergistic effect of zinc sulfate in combination with antibiotics on S. aureus was characterized using the checkerboard method. The influence of zinc sulfate on biofilm formation and virulence factors production by S. aureus was experimentally assessed. RT-qPCR was used to investigate the effect of zinc sulfate on the expression of biofilm-related genes. Zinc sulfate exhibited good antibacterial activity against S. aureus with a MIC of 128 µg/ml against all tested isolates. Also, the findings indicate a synergistic effect of a combination of zinc sulfate and antibiotics against the tested isolates. Zinc sulfate at 256 µg/ml concentration inhibited biofilm formation for all isolates. The expression of biofilm-related genes was significantly repressed in zinc sulfate-treated bacteria compared to untreated cells. Zinc sulfate could inhibit the hemolytic ability of S. aureus. Moreover, zinc sulfate-treated bacteria exhibited a significant decrease in coagulase and catalase activity relative to control untreated S. aureus. Our results support that zinc sulfate is a potential antimicrobial and anti-virulence agent against S. aureus infections.}, }
@article {pmid39466794, year = {2024}, author = {Islayem, M and Agha, A and Al Bataineh, MT and Bataineh, MS and Alazzam, A}, title = {Modification of surface topographies to inhibit candida biofilm formation.}, journal = {PloS one}, volume = {19}, number = {10}, pages = {e0308705}, pmid = {39466794}, issn = {1932-6203}, mesh = {*Biofilms/growth &amp; development ; *Candida albicans/physiology ; *Surface Properties ; Wettability ; }, abstract = {The rise of infections associated with indwelling medical devices is a growing concern, often complicated by biofilm formation leading to persistent infections. This study investigates a novel approach to prevent Candida albicans attachment on the surface by altering surface topography. The research focuses on two distinct surface topographies: symmetry (squares) and non-symmetry (lines), created through a direct laser photolithography process on a Cyclic olefin copolymer (COC) surface. The wettability of these patterned surfaces was then examined immediately after fabrication and plasma treatment to mimic the sterilization process of indwelling devices through UV plasma. The results reveal directional wettability in the line pattern and size-dependent wettability in both square and line patterns. Candida albicans were cultured on these surfaces to assess the efficacy of the topography in preventing biofilm formation. The study demonstrates that symmetry and non-symmetry pattern topography inhibit biofilm formation, providing a promising strategy for mitigating Candida-associated infections on medical devices. The research sheds light on the potential of surface modification techniques to enhance the biocompatibility of medical devices and reduce the risk of biofilm-related infections.}, }
@article {pmid39466757, year = {2024}, author = {Dlamini, SB and Mlambo, V and Mnisi, CM and Ateba, CN}, title = {Virulence, multiple drug resistance, and biofilm-formation in Salmonella species isolated from layer, broiler, and dual-purpose indigenous chickens.}, journal = {PloS one}, volume = {19}, number = {10}, pages = {e0310010}, pmid = {39466757}, issn = {1932-6203}, mesh = {Animals ; *Chickens/microbiology ; *Biofilms/growth &amp; development/drug effects ; Virulence/genetics ; *Drug Resistance, Multiple, Bacterial/genetics ; *Anti-Bacterial Agents/pharmacology ; *Salmonella/pathogenicity/isolation &amp; purification/genetics/drug effects ; Poultry Diseases/microbiology ; Salmonella Infections, Animal/microbiology ; Microbial Sensitivity Tests ; }, abstract = {Globally, the significant risk to food safety and public health posed by antimicrobial-resistant foodborne Salmonella pathogens is driven by the utilization of in-feed antibiotics, with variations in usage across poultry production systems. The current study investigated the occurrence of virulence, antimicrobial resistant profiles, and biofilm-forming potentials of Salmonella isolates sourced from different chicken types. A total of 75 cloacal faecal samples were collected using sterile swabs from layer, broiler, and indigenous chickens across 15 poultry farms (five farms per chicken type). The samples were analysed for the presence of Salmonella spp. using species-specific PCR analysis. Out of the 150 presumptive isolates, a large proportion (82; 55%) were confirmed as Salmonella species, comprising the serovars S. typhimurium (49%) and S. enteritidis (30%) while 21% were uncategorised. Based on phenotypic antibiotic susceptibility test, the Salmonella isolates were most often resistant to erythromycin (62%), tetracycline (59%), and trimethoprim (32%). The dominant multiple antibiotic resistance phenotypes were SXT-W-TE (16%), E-W-TE (10%), AML-E-TE (10%), E-SXT-W-TE (13%), and AMP-AML-E-SXT-W-TE (10%). Genotypic assessment of antibiotic resistance genes revealed that isolates harboured the ant (52%), tet (A) (46%), sui1 (13%), sui2 (14%), and tet (B) (9%) determinants. Major virulence genes comprising the invasion gene spiC, the SPI-3 encoded protein (misL) that is associated with the establishment of chronic infections and host specificity as well as the SPI-4 encoded orfL that facilitates adhesion, autotransportation and colonisation were detected in 26%, 16%, and 14% of the isolates respectively. There was no significant difference on the proportion of Salmonella species and the occurrence of virulence and antimicrobial resistance determinants among Salmonella isolates obtained from different chicken types. In addition, neither the chicken type nor incubation temperature influenced the potential of the Salmonella isolates to form biofilms, although a large proportion (62%) exhibited weak to strong biofilm-forming potentials. Moderate to high proportions of antimicrobial resistant pathogenic Salmonella serovars were detected in the study but these did not vary with poultry production systems.}, }
@article {pmid39466341, year = {2024}, author = {Knap, K and Kwiecień, K and Ochońska, D and Reczyńska-Kolman, K and Pamuła, E and Brzychczy-Włoch, M}, title = {Synergistic effect of antibiotics, α-linolenic acid and solvent type against Staphylococcus aureus biofilm formation.}, journal = {Pharmacological reports : PR}, volume = {76}, number = {6}, pages = {1456-1469}, pmid = {39466341}, issn = {2299-5684}, support = {2019/35/B/ST5/01103//Narodowe Centrum Nauki/ ; Program "Excellence initiative- research university" for the AGH University of Krakow//Ministerstwo Edukacji i Nauki/ ; }, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology ; *Staphylococcus aureus/drug effects ; *Drug Synergism ; *alpha-Linolenic Acid/pharmacology ; *Microbial Sensitivity Tests ; Solvents/chemistry/pharmacology ; Tobramycin/pharmacology ; Quorum Sensing/drug effects ; Azithromycin/pharmacology ; Gentamicins/pharmacology ; Dimethyl Sulfoxide/pharmacology ; }, abstract = {BACKGROUND: A promising approach to the treatment of bacterial infections involves inhibiting the quorum sensing (QS) mechanism to prevent the formation and growth of bacterial biofilm. While antibiotics are used to kill remaining bacteria, QS inhibitors (QSIs) allow for antibiotic doses to be reduced. This study focuses on evaluating the synergy between gentamicin sulphate (GEN), tobramycin (TOB), or azithromycin (AZM) with linolenic acid (LNA) against the formation of an early Staphylococcus aureus biofilm.<br><br>METHODS: Minimum biofilm inhibitory concentration (MBIC) was determined using the resazurin reduction assay for all antibiotics and LNA. The reduction of biofilm mass was assessed using the crystal violet (CV) assay. We have also evaluated the effect of dimethyl sulfoxide with TWEEN (DMSO_T) on early biofilm formation. Synergy was determined by metabolic activity assay and fractional biofilm inhibitory concentration (FBIC).<br><br>RESULTS: DMSO_T at a concentration of 1% enhanced early biofilm formation, but also decreased the doses of antibiotic needed to reduce the biofilm by up to 8 times. Adding LNA at a concentration of 32&#xa0;&#xb5;g/ml or 64&#xa0;&#xb5;g/ml allowed up to a 32-fold reduction of antibiotic doses for GEN and TOB and a 4-fold reduction for AZM.<br><br>CONCLUSIONS: LNA's use in combination with various antibiotics could reduce their doses and help fight drug-resistant bacteria in the biofilm.}, }
@article {pmid39465266, year = {2024}, author = {Deepak, SJ and Kannan, P and Savariraj, WR and Ayyasamy, E and Tuticorin Maragatham Alagesan, SK and Ravindran, NB and Sundaram, S and Mohanadasse, NQ and Kang, Q and Cull, CA and Amachawadi, RG}, title = {Characterization of Staphylococcus aureus isolated from milk samples for their virulence, biofilm, and antimicrobial resistance.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {25635}, pmid = {39465266}, issn = {2045-2322}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Milk/microbiology ; Animals ; *Staphylococcus aureus/genetics/drug effects/isolation &amp; purification/pathogenicity ; Anti-Bacterial Agents/pharmacology ; Virulence/genetics ; Microbial Sensitivity Tests ; Methicillin-Resistant Staphylococcus aureus/genetics/isolation &amp; purification/drug effects/pathogenicity ; Drug Resistance, Bacterial/genetics ; Staphylococcal Infections/microbiology/epidemiology ; Enterotoxins/genetics ; Food Microbiology ; Cattle ; }, abstract = {The Staphylococcus aureus (S. aureus) one of the important food borne pathogen from milk, which was investigated in this study. The isolates were screened for antimicrobial resistance, enterotoxin genes, biofilm formation, spa typing, coagulase gene polymorphism and accessory gene regulator types. The prevalence of S. aureus in milk samples was 34.4% (89/259). Methicillin resistant S. aureus (MRSA) was found at 27% (24/89) of the isolates, were classified as community acquired based on SCCmec typing. The 24.71% (22/89) isolates demonstrated multiple antimicrobial resistance (MAR) pattern. However, none of the isolates carried vancomycin and mupirocin resistance genes. The isolates were positive for sea and sed enterotoxin genes and exhibited high frequency of biofilm formation. The High-Resolution Melting and conventional spa typing revealed that the isolates had both animal and community-associated S. aureus clustered origins. Coagulase gene polymorphism and agr typing demonstrated variable genotypic patterns. The finding of this study establishes the prevalence of community associated, enterotoxigenic, biofilm forming and antimicrobial resistance among S. aureus from milk in Chennai city. This emphasizing a potential threat to public health which needs a continuous monitoring system and strategies to mitigate their spread across the food chain and achieve food safety.}, }
@article {pmid39464502, year = {2024}, author = {Wen, T and Xiong, S and Zhao, H and Wang, J and Wang, C and Long, Z and Xiong, L and Qian, G}, title = {Polylactic acid-based dressing with oxygen generation and enzyme-like activity for accelerating both light-driven biofilm elimination and wound healing.}, journal = {Burns &amp; trauma}, volume = {12}, number = {}, pages = {tkae041}, pmid = {39464502}, issn = {2321-3868}, abstract = {BACKGROUND: Photodynamic therapy (PDT) is a widely used therapeutic approach for eradicating bacterial biofilms in infected wound, but its effectiveness is limited by the hypoxic environment within the biofilm. This study aimed to investigate whether the efficiency of photodynamic removing biofilm is improving by providing oxygen (O2), as well as the expression of cytokines involved in infected wound healing.<br><br>METHODS: Manganese dioxide (MnO2) nanoparticles with catalase-like activity were grown in situ on graphitic phase carbon nitride (g-C3N4, CN) nanosheets to construct an all-in-one CN-MnO2 nanozyme, which was then incorporated into poly-L-lactic acid (PLLA) to prepare CN-MnO2/PLLA wound dressing by electrospinning. Subsequently, the in vitro antibacterial biofilm ratio and antibacterial ratio of CN-MnO2/PLLA wound dressing were examined by spread plate and crystal violet staining under irradiation with 808&#xa0;nm near-infrared light and 660&#xa0;nm visible light. Meanwhile, the rat skin injury model was established, and hematoxylin and eosin (H&amp;E), Masson's, tumor necrosis factor-&#x3b1; (TNF-&#x3b1;), Arginase 1 (Arg-1), vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (BFGF) were evaluated in vivo to assess the effect of CN-MnO2/PLLA wound dressing on wound healing.<br><br>RESULTS: Biofilm density caused by Staphylococcus aureus and Pseudomonas aeruginosa had elimination rates of 83 and 62%, respectively, when treated with CN-MnO2/PLLA dressing. Additionally, the dressing exhibited high antibacterial efficacy against both bacteria, achieving 99 and 98.7% elimination of Staphylococcus aureus and Pseudomonas aeruginosa, respectively. Furthermore, in vivo experiments showed that the CN-MnO2/PLLA wound dressing achieved complete healing of infected wounds on Day 14, with a wound healing rate of >99% by increasing collagen deposition, expression of anti-inflammatory cytokine Arg-1, vascularization cytokine VEGF, and epithelial cell BFGF, and inhibiting the expression of inflammatory cytokine TNF-&#x3b1;.<br><br>CONCLUSIONS: The CN-MnO2/PLLA wound dressing exhibited excellent antibacterial properties in vitro and in vivo. In addition, CN-MnO2/PLLA wound dressing accelerated rapid wound healing through an anti-inflammatory, pro-vascular regeneration and skin tissue remodeling mechanism.}, }
@article {pmid39464101, year = {2024}, author = {Lariviere, PJ and Ashraf, AHMZ and Gifford, I and Tanguma, SL and Barrick, JE and Moran, NA}, title = {Virulence-linked adhesin drives mutualist colonization of the bee gut via biofilm formation.}, journal = {bioRxiv : the preprint server for biology}, volume = {}, number = {}, pages = {}, pmid = {39464101}, issn = {2692-8205}, support = {R35 GM131738/GM/NIGMS NIH HHS/United States ; }, abstract = {Bacterial biofilms are stable multicellular structures that can enable long term host association. Yet, the role of biofilms in supporting gut mutualism is still not fully understood. Here, we investigate Snodgrassella alvi, a beneficial bacterial symbiont of honey bees, and find that biofilm formation is required for its colonization of the bee gut. We constructed fifteen S. alvi mutants containing knockouts of genes known to promote colonization with putative roles in biofilm formation. Genes required for colonization included staA and staB, encoding trimeric autotransporter adhesins (TAAs) and mltA, encoding a lytic transglycosylase. Intriguingly, TAAs are considered virulence factors in pathogens but support mutualism by the symbiont S. alvi. In vitro, biofilm formation was reduced in ΔstaB cells and abolished in the other two mutants. Loss of staA also reduced auto-aggregation and cell-cell connections. Based on structural predictions, StaA/B are massive (>300 nm) TAAs with many repeats in their stalk regions. Further, we find that StaA/B are conserved across Snodgrassella species, suggesting that StaA/B-dependent colonization is characteristic of this symbiont lineage. Finally, staA deletion increases sensitivity to bactericidal antimicrobials, suggesting that the biofilm indirectly buffers against antibiotic stress. In all, the inability of two biofilm-deficient strains (ΔstaA and ΔmltA) to effectively mono-colonize bees indicates that S. alvi biofilm formation is required for colonization of the bee gut. We envision the bee gut system as a genetically tractable model for studying the physical basis of biofilm-mutualist-gut interactions.}, }
@article {pmid39463994, year = {2024}, author = {Squyres, GR and Newman, DK}, title = {Real-time high-resolution microscopy reveals how single-cell lysis shapes biofilm matrix morphogenesis.}, journal = {bioRxiv : the preprint server for biology}, volume = {}, number = {}, pages = {}, pmid = {39463994}, issn = {2692-8205}, support = {R01 AI127850/AI/NIAID NIH HHS/United States ; }, abstract = {During development, multiscale patterning requires that cells organize their behavior in space and time. Bacteria in biofilms must similarly dynamically pattern their behavior with a simpler toolkit. Like in eukaryotes, morphogenesis of the extracellular matrix is essential for biofilm development, but how it is patterned has remained unclear. Here, we explain how the architecture of eDNA, a key matrix component, is controlled by single cell lysis events during Pseudomonas aeruginosa biofilm development. We extend single-cell imaging methods to capture complete biofilm development, characterizing the stages of biofilm development and visualizing eDNA matrix morphogenesis. Mapping the spatiotemporal distribution of single cell lysis events reveals that cell lysis is restricted to a specific biofilm zone. Simulations indicate that this patterning couples cell lysis to growth, more uniformly distributing eDNA throughout the biofilm. Finally, we find that patterning of cell lysis is organized by nutrient gradients that act as positioning cues.}, }
@article {pmid39463041, year = {2025}, author = {Wang, G and Zhang, C and Huang, Z and Chen, J and Chen, H and Lin, T and Zhou, Z and Gu, N and Huang, P}, title = {Transcytosable and Ultrasound-Activated Liposome Enables Deep Penetration of Biofilm for Surgical Site Infection Management.}, journal = {Advanced materials (Deerfield Beach, Fla.)}, volume = {37}, number = {1}, pages = {e2411092}, doi = {10.1002/adma.202411092}, pmid = {39463041}, issn = {1521-4095}, support = {2019C03077//Key Research and Development Program of Zhejiang Province/ ; 82030048//National Natural Science Foundation of China/ ; 82230069//National Natural Science Foundation of China/ ; 82371967//National Natural Science Foundation of China/ ; 82102191//National Natural Science Foundation of China/ ; }, mesh = {*Biofilms/drug effects ; *Liposomes/chemistry ; Animals ; Humans ; Ultrasonic Waves ; Anti-Bacterial Agents/chemistry/pharmacology ; Reactive Oxygen Species/metabolism ; Human Umbilical Vein Endothelial Cells ; Fluorocarbons/chemistry/pharmacology ; }, abstract = {Biofilm-associated surgical site infection (BSSI) is a common and grievous postoperative complication lacking effective remedies, mainly due to the poor drug accumulation and penetration in the biofilms featured by dense extracellular polymeric substances (EPSs). Here, it is found that the vascular cell adhesion molecule-1 (VCAM1) is highly overexpressed in the vascular cells of BSSI. It is proposed that the combination of VCAM1-mediated transcytosis and ultrasonic cavitation can consecutively overcome the biological barriers of vascular endothelial cells and EPS for biofilm eradication. To demonstrate the feasibility, a VCAM1-targeted and ultrasound (US)-activated liposome (LPCOTML) loaded with a reactive-oxygen-species (ROS)-responsive lipoid prodrug of oleoyl meropenem, sonosensitizer of lipoid Ce6, and perfluoropentane is developed. LPCOTML can recognize the receptors on vascular cells, and initiate receptor-mediated transcytosis for transendothelial transport into the BSSI periphery. LPCOTML subsequently transforms from nanoparticle into microbubble via liquid-gas phase transition under US irradiation, triggering strong ultrasonic cavitation to blow up the EPS and deeply penetrate the biofilms. The sonosensitizer Ce6 induces ROS production under US irradiation and triggers the release of meropenem to induce potent antibacterial effect in a BSSI model. This study presents an effective strategy to tackle the biological barriers in BSSI via combining receptor-mediated transcytosis and ultrasonic cavitation.}, }
@article {pmid39461526, year = {2024}, author = {Huang, QS and Chen, SQ and Zhao, XM and Song, LJ and Deng, YM and Xu, KW and Yan, ZF and Wu, J}, title = {Enhanced degradation of polyethylene terephthalate (PET) microplastics by an engineered Stenotrophomonas pavanii in the presence of biofilm.}, journal = {The Science of the total environment}, volume = {955}, number = {}, pages = {177129}, doi = {10.1016/j.scitotenv.2024.177129}, pmid = {39461526}, issn = {1879-1026}, mesh = {*Polyethylene Terephthalates/metabolism ; *Biofilms ; *Stenotrophomonas/metabolism/genetics ; *Biodegradation, Environmental ; *Microplastics ; Water Pollutants, Chemical/metabolism ; Hydrolases/metabolism/genetics ; }, abstract = {Polyethylene terephthalate (PET) microplastics pose significant environmental and human health risks due to their resistance to degradation and accumulation in ecosystems. In this study, we engineered Stenotrophomonas pavanii JWG-G1, a robust biofilm-forming bacterium, to overexpress the PET hydrolase (DuraPETase) for PET microplastics degradation at ambient temperature. Nine endogenous PET hydrolases were identified through genome sequencing of S. pavanii, and were successfully expressed in Escherichia coli BL21(DE3). Among them, hydrolase Est_B achieved 100% degradation of bis(2-hydroxyethyl) terephthalate (BHET) at an initial concentration of 0.23 mg/mL at 30 °C within 4 h, identifying it as a novel BHETase. However, the PET degradation performance of all endogenous PET hydrolases was inferior to that of DuraPETase. The engineered strain overexpressing DuraPETase demonstrated a significant enhancement in PET degradation, achieving a 38.04 μM total product release of high-crystallinity PET microplastics after 30 days at 30 °C. The degradation extent was greater than that of low biofilm-forming engineered strains, attributing to the aggregation of DuraPETase on the PET surface in the presence of biofilm. Additionally, this engineered strain also maintained PET degradation activity across various water environments and demonstrated effectiveness in degrading other polyester plastics. This is the first report demonstrating that an engineered strain of Stenotrophomonas species is capable of simultaneously secreting exogenous hydrolase and degrading polyester microplastics, representing a novel approach in the development of engineered bacteria with potential applications in bioreactor systems and environmental remediation.}, }
@article {pmid39461210, year = {2025}, author = {Hu, Y and Li, R and Bian, K and Zhou, Q and Pan, Y and Ye, L and Li, A and Shi, P}, title = {Biofilm formation dynamics in long-distance water conveyance pipelines: Impacts of nutrient levels and metal stress.}, journal = {Water research}, volume = {268}, number = {Pt A}, pages = {122672}, doi = {10.1016/j.watres.2024.122672}, pmid = {39461210}, issn = {1879-2448}, mesh = {*Biofilms ; *Water Supply ; *Metals/analysis ; Bioreactors ; Water Quality ; Biomass ; Polysaccharides, Bacterial/metabolism ; Bacteria/classification ; Bacterial Proteins/metabolism ; *Phosphorus/analysis ; *Nitrogen/analysis ; }, abstract = {Biofilm formation in long-distance water conveyance pipelines poses significant risks to water quality, particularly under varying nutrient levels and heavy metal stress. However, the impacts of pipeline material on biofilm formation dynamics under different raw water conditions remain elusive. This study investigated the effects of nutrient availability and Fe-Mn stress on biofilm development, structural stability, bacterial community composition, and the occurrence of viable but non-culturable (VBNC) bacteria. Using reactors with different nutrient conditions, we observed that increased nutrient levels promote biofilm growth but lead to greater instability, heightening the risk of secondary contamination. Notably, nutrient escalation beyond a critical threshold had a diminishing impact on biofilm community composition. Additionally, Fe-Mn stress, while initially enhancing microbial adhesion and metabolic activity, ultimately inhibited biofilm formation over time and increases the prevalence of VBNC bacteria, particularly on stainless steel (SS) surfaces. Our findings also highlighted the importance of material selection for pipelines, with polyvinyl chloride (PVC) showing reduced biofilm formation compared to SS, making it a more suitable option for transporting raw water in environments with high metal content. Dispersal limitation determined the bacterial community assembly during the biofilm formation, accounting for 64.53-90.67 % of the variability in different scenarios. These insights offer valuable guidance for managing biofilm-related issues in water distribution systems, emphasizing the need for careful control of nutrient levels and material choice to ensure water safety over long distances.}, }
@article {pmid39459765, year = {2024}, author = {Wang, Y and Zhang, R and Mathivanan, K and Zhang, Y and Yang, L and Guan, F and Duan, J}, title = {Proteomics and EPS Compositional Analysis Reveals Desulfovibrio bisertensis SY-1 Induced Corrosion on Q235 Steel by Biofilm Formation.}, journal = {Materials (Basel, Switzerland)}, volume = {17}, number = {20}, pages = {}, pmid = {39459765}, issn = {1996-1944}, support = {42076044//National Natural Science Foundation of China/ ; ZDBS-LY-DQC025//Key Research Program of Frontier Sciences, CAS/ ; }, abstract = {Microorganisms that exist in the seawater form microbial biofilms on materials used in marine construction, especially on metal surfaces submerged in seawater, where they form biofilms and cause severe corrosion. Biofilms are mainly composed of bacteria and their secreted polymeric substances. In order to understand how biofilms promote metal corrosion, planktonic and biofilm cells of Desulfovibrio bizertensis SY-1 (D. bizertensis) from Q235 steel were collected and analyzed as to their intracellular proteome and extracellular polymeric substances (EPS). The intracellular proteome analysis showed that the cellular proteins were strongly regulated in biofilm cells compared to planktonic cells, e.g., along with flagellar proteins, signaling-related proteins were significantly increased, whereas energy production and conversion proteins and DNA replication proteins were significantly regulated. The up-and-down regulation of proteins revealed that biofilm formation by bacteria on metal surfaces is affected by flagellar and signaling proteins. A significant decrease in DNA replication proteins indicated that DNA is no longer replicated and transcribed in mature biofilms, thus reducing energy consumption. Quantitative analysis and lectin staining of the biofilm on the metal's surface revealed that the bacteria secreted a substantial amount of EPS when they began to attach to the surface, and proteins dominated the main components of EPS. Further, the infrared analysis showed that the secondary structure of the proteins in the EPS of the biofilm was mainly dominated by β-sheet and 3-turn helix, which may help to enhance the adhesion of EPS. The functional groups of EPS analyzed using XPS showed that the C element of EPS in the biofilm mainly existed in the form of combinations with N. Furthermore, the hydroxyl structure in the EPS extracted from the biofilm had a stronger hydrogen bonding effect, which could maintain the stability of the EPS structure and biofilm. The study results revealed that D. bizertensis regulates the metabolic pathways and their secreted EPS structure to affect biofilm formation and cause metal corrosion, which has a certain reference significance for the study of the microbially influenced corrosion (MIC) mechanism.}, }
@article {pmid39459561, year = {2024}, author = {Coelho, MMS and Davanzo, EFA and Dos Santos, RL and Castro, VHL and da Costa, HMB and Dallago, BSL and Perecmanis, S and Santana, AP}, title = {Escherichia coli and Enterobacteriaceae Counts, Virulence Gene Profile, Antimicrobial Resistance, and Biofilm Formation Capacity during Pig Slaughter Stages.}, journal = {Life (Basel, Switzerland)}, volume = {14}, number = {10}, pages = {}, pmid = {39459561}, issn = {2075-1729}, support = {R$ 8,500//Universidade de Bras&#xed;lia/ ; }, abstract = {This study aimed to count Enterobacteriaceae and Escherichia coli in different locations on pig carcasses (shank, loin, abdomen, shoulder, and jowl) from two slaughterhouses (A and B) between September 2019 and July 2021 during different slaughter stages (after bleeding, after passing through the epilator machine, after manual toileting in the dirty area, before and after evisceration, and after the final washing), as well as verify antimicrobial resistance and biofilm formation capacity. The main points of Enterobacteriaceae and E. coli contamination were identified in the two slaughterhouses through three collections. The stages with the highest counts were post-bleeding and evisceration in both slaughterhouses and after manual toileting in slaughterhouse B in the first collection. Most E. coli isolates were resistant to multiple antimicrobials, with higher resistance frequencies to amoxicillin, ampicillin, chloramphenicol, sulfonamides, and streptomycin. The virulence genes eae, stx1, and stx2 were also detected. Three isolates had all three genes and exhibited resistance to at least six antimicrobial classes (β-lactams, macrolides, aminoglycosides, sulfonamides, amphenicols, and quinolones). E. coli isolates also showed a high frequency of strains with moderate and strong in vitro biofilm-forming capacity. This is the first study to characterize microbial contamination by pig slaughter stage in the Federal District region, demonstrating the critical points for hygienic production. E. coli was isolated from the surface of pig carcasses, as well as the virulence genes stx1, stx2, and eae were detected. The multi-antimicrobial resistant isolates also had a moderate-to-strong biofilm formation capacity, thus demonstrating risks to public health.}, }
@article {pmid39459275, year = {2024}, author = {Kim, ES and Park, BI and Kim, YH and Kang, J and You, YO}, title = {The Inhibitory Effect of Agastache rugosa Essential Oil on the Dental Biofilm.}, journal = {Molecules (Basel, Switzerland)}, volume = {29}, number = {20}, pages = {}, pmid = {39459275}, issn = {1420-3049}, mesh = {*Biofilms/drug effects ; *Oils, Volatile/pharmacology/chemistry ; *Streptococcus mutans/drug effects ; *Agastache/chemistry ; Gas Chromatography-Mass Spectrometry ; Dental Caries/microbiology/prevention &amp; control/drug therapy ; Allylbenzene Derivatives/pharmacology ; Anisoles/pharmacology/chemistry ; Virulence Factors ; Anti-Bacterial Agents/pharmacology/chemistry ; Humans ; Sesquiterpenes/pharmacology/chemistry ; Microbial Sensitivity Tests ; Limonene/pharmacology/chemistry ; Gene Expression Regulation, Bacterial/drug effects ; }, abstract = {This study aimed to identify the inhibitory effect of Agastache rugosa essential oil (AREO) on the cariogenic properties of Streptococcus mutans, which causes dental caries and dental plaque formation. After extracting the AREO, their effects on the growth and acid production of S. mutans were examined. Furthermore, S. mutans biofilm formation was observed on the resin teeth surface. The effect on the expression of biofilm-related genes of S. mutans was measured using real-time PCR. AREO components were analyzed using gas chromatography (GC) and GC-mass spectrometry (MS). The growth and acid production of S. mutans were significantly inhibited at concentrations of 0.02 mg/mL or higher of AREO. At 0.04 mg/mL, inhibition was similar to that of the positive control, 0.1% NaF. AREO suppressed the expression of virulence factors such as gtfB, gtfC, gtfD, gbpB, SpaP, brpA, relA, and vicR at concentrations of 0.02 mg/mL or higher. As a result of GC and GC-MS analyses, the main components of AREO included estragole, limonene, and β-caryophyllene. These results suggest that A. rugosa may be a useful agent for inhibiting the cariogenic properties of S. mutans.}, }
@article {pmid39458421, year = {2024}, author = {Sharma, S and Mohler, J and Mahajan, SD and Schwartz, SA and Bruggemann, L and Aalinkeel, R}, title = {Correction: Sharma et al. Microbial Biofilm: A Review on Formation, Infection, Antibiotic Resistance, Control Measures, and Innovative Treatment. Microorganisms 2023, 11, 1614.}, journal = {Microorganisms}, volume = {12}, number = {10}, pages = {}, pmid = {39458421}, issn = {2076-2607}, abstract = {In the original publication [...].}, }
@article {pmid39458405, year = {2024}, author = {Coppolino, F and Berbiglia, A and Lentini, G and Famà, A and Pietrocola, G and Teti, G and Beninati, C and De Gaetano, GV}, title = {Role of the SaeRS Two-Component Regulatory System in Group B Streptococcus Biofilm Formation on Human Fibrinogen.}, journal = {Microorganisms}, volume = {12}, number = {10}, pages = {}, pmid = {39458405}, issn = {2076-2607}, support = {PRIN 2022 PNRR P2022BNCKS//the Ministry of University and Research (MIUR)/ ; }, abstract = {Streptococcus agalactiae, also known as Group B Streptococcus or GBS, is a commensal colonizer of human vaginal and gastrointestinal tracts that can also be a deadly pathogen for newborns, pregnant women, and the elderly. The SaeRS two-component regulatory system (TCS) positively regulates the expression of two GBS adhesins genes, but its role in the formation of biofilm, an important step in pathogenesis, has not been investigated. In the present study, we set up a novel model of GBS biofilm formation using surfaces coated with human fibrinogen (hFg). Biofilm mass and structure were analyzed by crystal violet staining and three-dimensional fluorescence microscopy, respectively. GBS growth on hFg resulted in the formation of a mature and abundant biofilm composed of bacterial cells and an extracellular matrix containing polysaccharides, proteins, and extracellular DNA (eDNA). Enzymatic and genetic analysis showed that GBS biofilm formation on hFg is dependent on proteins and eDNA in the extracellular matrix and on the presence of covalently linked cell wall proteins on the bacterial surface but not on the type-specific capsular polysaccharide. In the absence of the SaeR regulator of the SaeRS TCS, there was a significant reduction in biomass formation, with reduced numbers of bacterial cells, reduced eDNA content, and disruption of the biofilm architecture. Overall, our data suggest that GBS binding to hFg contributes to biofilm formation and that the SaeRS TCS plays an important role in this process.}, }
@article {pmid39458275, year = {2024}, author = {Codru, IR and Vintilă, BI and Sava, M and Bereanu, AS and Neamțu, SI and Bădilă, RM and Bîrluțiu, V}, title = {Optimizing Diagnosis and Management of Ventilator-Associated Pneumonia: A Systematic Evaluation of Biofilm Detection Methods and Bacterial Colonization on Endotracheal Tubes.}, journal = {Microorganisms}, volume = {12}, number = {10}, pages = {}, pmid = {39458275}, issn = {2076-2607}, abstract = {Healthcare-associated infections, such as ventilator-associated pneumonia and biofilm formation on intubation cannulas, impose significant burdens on hospitals, affecting staffing, finances, and patient wellbeing, while also increasing the risk of patient mortality. We propose a research study aimed at exploring various methodologies for detecting these infections, discovered in the biofilm on medical devices, particularly tracheal cannulas, and understanding the role of each method in comprehending these infections from an etiological perspective. Our investigation also involves an analysis of the types of endotracheal tubes utilized in each case, the bacteria species identified, and strategies for combating biofilm-associated infections. The potential impact of our research is the substantial improvement of patient care through enhanced diagnosis and management of these infections.}, }
@article {pmid39458274, year = {2024}, author = {Di Spirito, F and Pisano, M and Di Palo, MP and Franci, G and Rupe, A and Fiorino, A and Rengo, C}, title = {Peri-Implantitis-Associated Microbiota before and after Peri-Implantitis Treatment, the Biofilm "Competitive Balancing" Effect: A Systematic Review of Randomized Controlled Trials.}, journal = {Microorganisms}, volume = {12}, number = {10}, pages = {}, pmid = {39458274}, issn = {2076-2607}, abstract = {This systematic review of RCTs aimed to characterize short- and long-term changes in peri-implantitis-associated microbiota (total biofilm microbial load and predominant pathogens' counts) following (any) peri-implantitis treatment in systemically healthy, non-smoking, partially/totally edentulous adults. The study protocol, compliant with the PRISMA statement, was registered on PROSPERO (CRD42024514521) before the literature search. Data from 11 RCTs, assessed through the ROBINS-2 tool, were qualitatively synthesized. No data were retrieved on total edentulism, healthy peri-implant/periodontal sites, treated mucositis, gingivitis, and periodontitis sites. Shortly after treatment, Prevotella intermedia, Fusobacterium nucleatum, and Peptostreptococcus micros prevailed, indicating early colonization, as after implant placement. After both surgical and non-surgical approaches, although not eradicated, the peri-implant total biofilm load, red- and orange-complex species, and Aggregatibacter actinomycetemcomitans counts generally decreased for up to about three months. However, one month after treatment, red-complex species and Prevotella intermedia increased, likely due to persistent tissue-invasive bacteria, unresolved pathological conditions (high probing depth values) favoring anaerobiosis and dysbiosis, and a qualitatively and quantitatively decreased biofilm community, competing and balancing the predominant pathogens (biofilm "competitive balancing" effect), thus allowing recolonization by more virulent bacteria. Red-complex bacteria gradually leveled off to baseline at the six- and twelve-month follow-ups. Fusobacterium nucleatum remained almost unchanged after treatment.}, }
@article {pmid39458266, year = {2024}, author = {Tyagi, A and Kumar, V and Joshi, N and Dhingra, HK}, title = {Combinatorial Effects of Ursodeoxycholic Acid and Antibiotic in Combating Staphylococcus aureus Biofilm: The Roles of ROS and Virulence Factors.}, journal = {Microorganisms}, volume = {12}, number = {10}, pages = {}, pmid = {39458266}, issn = {2076-2607}, abstract = {Staphylococcus aureus is a biofilm-forming bacterium responsible for various human infections, one particularly challenging to treat due to its antibiotic resistance. Biofilms can form on both soft tissues and medical devices, leading to persistent and hard-to-treat infections. Combining multiple antimicrobials is a potential approach to overcoming this resistance. This study explored the effects of ursodeoxycholic acid (UDCA) combined with the antibiotic ciprofloxacin against S. aureus biofilms, aiming to evaluate any synergistic effects. Results showed that UDCA and ciprofloxacin co-treatment significantly reduced biofilm formation and disrupted pre-formed biofilms more effectively than either agent alone (p < 0.01). The combination also displayed a slight synergistic effect, with a fractional inhibitory concentration of 0.65. Additionally, the treatment reduced the production of extracellular polymeric substances, increased reactive oxygen species production, decreased metabolic activity, altered cell membrane permeability, and lowered cell surface hydrophobicity in S. aureus. Furthermore, it diminished biofilm-associated pathogenic factors, including proteolytic activity and staphyloxanthin production. Overall, the UDCA-ciprofloxacin combination shows considerable promise as a strategy to combat infections related to staphylococcal biofilms, offering a potential solution to the healthcare challenges posed by antibiotic-resistant S. aureus.}, }
@article {pmid39458248, year = {2024}, author = {Iungin, O and Prekrasna-Kviatkovska, Y and Kalinichenko, O and Moshynets, O and Potters, G and Sidorenko, M and Savchuk, Y and Mickevičius, S}, title = {Endophytic Bacterial Biofilm-Formers Associated with Antarctic Vascular Plants.}, journal = {Microorganisms}, volume = {12}, number = {10}, pages = {}, pmid = {39458248}, issn = {2076-2607}, support = {0121U112259 &#xab;Study on physiological and biochemical properties and biofilm formation of bac-teria isolated from vascular plants of Antarctica&#xbb;//State Institution National Antarctic Scientific Center/ ; }, abstract = {Deschampsia antarctica and Colobantus quitensis are the only two vascular plants colonized on the Antarctic continent, which is usually exposed to extreme environments. Endophytic bacteria residing within plant tissues can exhibit diverse adaptations that contribute to their ecological success and potential benefits for their plant hosts. This study aimed to characterize 12 endophytic bacterial strains isolated from these plants, focusing on their ecological adaptations and functional roles like plant growth promotion, antifungal activities, tolerance to salt and low-carbon environments, wide temperature range, and biofilm formation. Using 16S rRNA sequencing, we identified several strains, including novel species like Hafnia and Agreia. Many strains exhibited nitrogen-fixing ability, phosphate solubilization, ammonia, and IAA production, potentially benefiting their hosts. Additionally, halotolerance and carbon oligotrophy were also shown by studied bacteria. While some Antarctic bacteria remain strictly psychrophilic, others demonstrate a remarkable ability to tolerate a wider range of temperatures, suggesting that they have acquired mechanisms to cope with fluctuations in environmental temperature and developed adaptations to survive in intermediate hosts like mammals and/or birds. Such adaptations and high plasticity of metabolism of Antarctic endophytic bacteria provide a foundation for research and development of new promising products or mechanisms for use in agriculture and technology.}, }
@article {pmid39458227, year = {2024}, author = {Assadian, H and Fathollahi, S and Pourhajibagher, M and Solimei, L and Benedicenti, S and Chiniforush, N}, title = {Effectiveness of Activated Sodium Hypochlorite Irrigation by Shock Wave-Enhanced Emission Photoacoustic Streaming, Sonic and Ultrasonic Devices in Removing Enterococcus faecalis Biofilm From Root Canal System.}, journal = {Journal of clinical medicine}, volume = {13}, number = {20}, pages = {}, pmid = {39458227}, issn = {2077-0383}, abstract = {Aim: To compare shock wave-enhanced emission photoacoustic streaming (SWEEPS) with sonic- and ultrasonically activated irrigation systems in removing Enterococcus faecalis biofilm from the root canal system. Methodology: Fifty human single-canalled mandibular premolars were included in the study. After access cavity preparation, the root canals were prepared to a standardized size and taper. Then, the entire root surface was covered with two layers of resin, and the root apices were sealed before sterilization. All root canals were inoculated with E. faecalis biofilm, and the samples were incubated aerobically for 2 weeks at 37 °C. Biofilm formation was confirmed by scanning electron microscopy. All samples were randomly divided into five groups (n = 10 each) based on their irrigation activation method as A (no treatment or negative control), B (no irrigation or positive control), C (sonically activated irrigation (SAI)), D (ultrasonically activated irrigation (UAI)), and E (needle irrigation activated by an Er: YAG laser device using a SWEEPS quartz tip (SWEEPS)). Then, dentine chips were retrieved, vortexed, and diluted for colony-forming unit counts. Data were analysed using analysis of variance and post-hoc Tukey tests (α = 5%). Results: All methods could significantly reduce E. faecalis biofilm compared with control so that the UAI, SWEEPS, and SAI groups indicated a 23.54%, 14.89%, and 7.81% biofilm reduction, respectively. UAI demonstrated a significantly more effective reduction of E. faecalis biofilm than SAI (p = 0.004). Conclusions: All irrigation activation methods significantly reduced E. faecalis biofilm, with ultrasonic use being the most effective.}, }
@article {pmid39457638, year = {2024}, author = {Kardaras, G and Boariu, M and Varlamov, V and Vintila, C and Boia, S and Belova, A and Rusu, D and Machoy, M and Solomon, SM and Stratul, SI}, title = {Three-Dimensional Planimetry Assessment of Dental Plaque-Covered Area Reduction after Rinsing with 0.2% Sodium Hypochlorite Solution as Part of a Guided Biofilm Therapy[®] Protocol-Pilot Longitudinal Study.}, journal = {Biomedicines}, volume = {12}, number = {10}, pages = {}, pmid = {39457638}, issn = {2227-9059}, support = {HCA 22/23790/18.10.2022//Victor Babes University Of Medicine And Pharmacy Timisoara/ ; }, abstract = {Background/Objectives: Less often employed as a rinsing solution for controlling oral biofilms, NaOCL was used in oral rinses at various concentrations in steps 1 and 4 of periodontal therapy. The aim of this study was to quantitatively evaluate the biofilm-disruptive properties of a 0.2% NaOCl solution in standardized oral rinses using dedicated plaque-disclosing agents and 3D scanning methods in patients undergoing the regular Guided Biofilm Therapy[®] protocol. Methods: Eight patients with at least 20 teeth present evenly distributed between the two arches were included. After 24 h of refraining from oral hygiene, dental arches were stained with a disclosing agent, the subjects rinsed for 20 s, clinical photographs and 3D scans were performed, subjects rinsed again for 20 s, photographs and 3D scans were performed again, and then the GBT[®] protocol was resumed as usual. Data representing areas covered with dental plaque were acquired using the "Medit Scan for Clinics" software and then underwent a post-processing and rendering process. The outcome variable was the percent reduction in the plaque-covered areas. Results: For the upper jaw, the estimated mean percent reduction in the biofilm-covered area was 39.65%, while for the mandible, it was 38.26%. The analysis of individual photographs revealed changes in the plaque-covered areas and reductions in the color intensity of the residual plaque-covered areas under identical lighting conditions. Conclusions: When analyzed using 3D intraoral scanning, the 0.2% NaOCl rinsing solution seems to be a clinically efficient disruptor/dissolvent of the oral biofilm, both when integrated into modern protocols of periodontal therapy like GBT[®] and for home self-care.}, }
@article {pmid39457603, year = {2024}, author = {Pérez, LM and Havryliuk, O and Infante, N and Muniesa, M and Morató, J and Mariychuk, R and Tzanov, T}, title = {Biofilm Prevention and Removal in Non-Target Pseudomonas Strain by Siphovirus-like Coliphage.}, journal = {Biomedicines}, volume = {12}, number = {10}, pages = {}, pmid = {39457603}, issn = {2227-9059}, support = {ID 1803//Federation of European Microbiology Societies (FEMS)/ ; "Pla d'Acci&#xf3; Universitat-447 Refugi" aimed at supporting the research activities of Ukrainian researchers in Spanish institutions//Spanish Government and Universitat Polit&#xe8;cnica de Catalunya-BarcelonaTech/ ; postdoctoral fellowship//Banco Santander and Universitat Polit&#xe8;cnica de Catalunya-BarcelonaTech/ ; }, abstract = {Background/Objectives. Bacteriophages have gained significant interest as a potential solution to combat harmful bacteria, especially in the fight against antimicrobial resistance. With the rise in drug-resistant microorganisms, the medical community is increasingly exploring new alternatives to traditional antibiotics, and bacteriophages offer several advantages in this regard. However, phage applications still face some challenges, such as host specificity. Methods. In this study, a somatic Siphovirus-like coliphage (SOM7) was tested for inhibiting the biofilm-forming capacity of the non-target strain Pseudomonas aeruginosa (ATTC 10145). The phage-sensitive strain E. coli WG5 was used as a control. The selected microorganisms were first tested for growth in the presence of SOM7 at three different concentrations (10[5], 10[7], and 10[9] PFU/mL). Results. As expected, the phage-sensitive E. coli WG5 was fully inhibited by the coliphage, and no phage-related affection on the growth rate was observed for the SOM7-resistant P. aeruginosa. More notably, increasing concentrations of SOM7 significantly reduced both the biofilm-forming capacity and the amount of pre-established bacterial biofilm of the phage-insensitive P. aeruginosa (24.9% and 38.8% reduction in the biofilm-forming ability, and 18.8% and 28.0% biofilm degradation for 10[7] PFU/mL and 10[9] PFU/mL SOM7, respectively; p < 0.05). These results were supported by transmission electron microscopy (TEM) imaging, providing unprecedent evidence for the interaction of the somatic coliphage with the non-host strain. Conclusions. Although more studies in other biofilm models are necessary, our results show for the very first time that bacteriophages could potentially be used as an alternative to achieve desired anti-biofilm and biofilm-degrading activity in non-host bacterial strains.}, }
@article {pmid39456313, year = {2024}, author = {Eced-Rodríguez, L and Beyrer, M and Rodrigo, D and Rivas, A and Esteve, C and Pina-Pérez, MC}, title = {Sublethal Damage Caused by Cold Plasma on Bacillus cereus Cells: Impact on Cell Viability and Biofilm-Forming Capacity.}, journal = {Foods (Basel, Switzerland)}, volume = {13}, number = {20}, pages = {}, pmid = {39456313}, issn = {2304-8158}, support = {PID2020-116318RA-C33//Ministerio de Ciencia e Innovaci&#xf3;n/ ; }, abstract = {The Bacillus cereus group represents a serious risk in powdered and amylaceous foodstuffs. Cold plasma (the fourth state of matter) is emerging as an alternative effective nonthermal technology for pasteurizing a wide range of matrices in solid, liquid, and powder form. The present study aims to evaluate the mechanisms involved in Bacillus cereus inactivation via cold plasma, focusing on (i) the technology's ability to generate damage in cells (at the morphological and molecular levels) and (ii) studying the effectiveness of cold plasma in biofilm mitigation through the direct effect and inhibition of the biofilm-forming capacity of sublethally damaged cells post-treatment. Dielectric barrier discharge cold plasma (DBD-CP) technology was used to inactivate B. cereus, B. thuringiensis, and B. mycoides under plasma power settings of 100, 200, and 300 W and treatment times ranging from 1 to 10 min. Inactivation levels were achieved in 2-7 log10 cycles under the studied conditions. Percentages of sublethally damaged cells were observed in a range of 45-98%, specifically at treatment times below 7 min. The sublethally damaged cells showed poration, erosion, and loss of integrity at the superficial level. At the molecular level, proteins and DNA leakage were also observed for B. cereus but were minimal for B. mycoides. Biofilms formed by B. cereus were progressively disintegrated under the DBD-CP treatment. The greater the CP treatment intensity, the greater the tearing of the bacteria's biofilm network. Additionally, cells sublethally damaged by DBD-CP were evaluated in terms of their biofilm-forming capacity. Significant losses in the damaged cells' biofilm network density and aggregation capacity were observed when B. cereus was recovered after inactivation at 300 W for 7.5 min, compared with the untreated cells. These results provide new insights into the future of tailored DBD-CP design conditions for both the inactivation and biofilm reduction capacity of B. cereus sensu lato species, demonstrating the effectiveness of cold plasma and the risks associated with sublethal damage generation.}, }
@article {pmid39456177, year = {2024}, author = {Iloabuchi, K and Spiteller, D}, title = {The Epiphyte Bacillus sp. G2112 Produces a Large Diversity of Nobilamide Peptides That Promote Biofilm Formation in Pseudomonads and Mycobacterium aurum.}, journal = {Biomolecules}, volume = {14}, number = {10}, pages = {}, pmid = {39456177}, issn = {2218-273X}, support = {39072414//GSC 218 Konstanz Research School Chemical Biology by the Deutsche Forschungsgemeinschaft/ ; TETF/ES/UNI/UNN/NSUKKA/ASTD/2017//doctoral fellowship by the Tertiary Education Trustfund Nigeria/ ; }, mesh = {*Bacillus ; *Biofilms/drug effects/growth &amp; development ; Pseudomonas ; Mycobacterium/drug effects ; Anti-Bacterial Agents/pharmacology/chemistry ; Peptides/pharmacology/chemistry ; Microbial Sensitivity Tests ; Peptides, Cyclic ; Depsipeptides ; }, abstract = {Bacillus sp. G2112, an isolate from cucumber plants that inhibited plant pathogens, produces not only surfactins, iturins, and fengycins common to many Bacillus spp., but also a large variety of N-acyl-(depsi)peptides related to A-3302-B and nobilamides. Four known and fourteen previously unreported nobilamide peptides were characterized using high-resolution mass spectrometry, tandem mass spectrometry, and NMR. The stereochemistry of the amino acids of nobilamide peptides was determined using Marfey's method. The diversity of nobilamide peptides from Bacillus sp. G2112 resulted from the incorporation of different acyl groups and amino acids in the sequence. The peptides occur in linear or cyclic form. In addition, a truncated N-acetylpentapeptide was produced. Agar diffusion assays with selected nobilamide peptides against plant pathogens and human pathogens revealed that A-3302-B and its N-acyl homologs, A-3302-A and nobilamide J, exhibited powerful antibiotic activity (at 5 µg/hole) against Lysinibacillus sphaericus that can cause severe sepsis and bacteremia in patients. Moreover, nobilamide peptides from Bacillus sp. G2112 strongly promoted biofilm formation in the Gram-positive Mycobacterium aurum and Gram-negative pseudomonads. Structurally diverse nobilamides from Bacillus sp. G2112, whether linear or cyclic, penta and heptapeptides, induced biofilm formation, suggesting that the common N-acetyl-D-Phe-D-Leu-L-Phe-D-allo-Thr-L-Val amino acid sequence motif is important for the biofilm-inducing activity.}, }
@article {pmid39454804, year = {2024}, author = {Mayattu, K and Rajwade, J and Ghormade, V}, title = {Development of erythromycin loaded PLGA nanoparticles for improved drug efficacy and sustained release against bacterial infections and biofilm formation.}, journal = {Microbial pathogenesis}, volume = {197}, number = {}, pages = {107083}, doi = {10.1016/j.micpath.2024.107083}, pmid = {39454804}, issn = {1096-1208}, mesh = {*Erythromycin/pharmacology ; *Biofilms/drug effects ; *Polylactic Acid-Polyglycolic Acid Copolymer/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Nanoparticles/chemistry ; *Microbial Sensitivity Tests ; *Staphylococcus aureus/drug effects ; *Pseudomonas aeruginosa/drug effects ; *Escherichia coli/drug effects ; Particle Size ; Delayed-Action Preparations ; Drug Carriers/chemistry ; Bacterial Infections/drug therapy ; Humans ; Drug Liberation ; }, abstract = {Bacterial infections are a common cause of sepsis, often leading to high patient mortality. Such infections are challenging to treat due to bacterial resistance to many existing drugs. Erythromycin (Ery) is a macrolide antibiotic used against bacterial infections with reported resistance. Recently, synthetic poly-lactide co-glycolic acid (PLGA) polymer nanoparticles (NPs) have displayed improved drug delivery characteristics and biocompatibility. In this study, PLGA-Ery NPs were synthesized by the o/w emulsion diffusion method, having a particle size of 159 ± 23 nm and displayed 71.89 % of encapsulation efficiency. The PLGA-Ery NPs showed 1.5, 2.1 and 1.5-fold improved MIC and antibacterial efficacy against E. coli, S. aureus, and P. aeruginosa, respectively than the pure drug. As illustrated by scanning electron microscopy, PLGA-Ery NPs caused damage to the bacterial cell walls. Furthermore, a surface coating with PLGA-Ery NPs on a glass surface showed efficient inhibition (>90 %) of the biofilm formation by P. aeruginosa, as determined by fluorescence microscopy and MTT assay. This study demonstrates that PLGA-Ery NPs can increase the efficiency of erythromycin and can suppress the growth and biofilm formation of P. aeruginosa. Such polymeric nanoparticles drug nanoformulations have potential as an antimicrobial and as a surface coating for medical devices.}, }
@article {pmid39454803, year = {2024}, author = {Lima, EMF and Bueris, V and Germano, LG and Sircili, MP and Pinto, UM}, title = {Synergistic effect of the combination of phenolic compounds and tobramycin on the inhibition of Pseudomonas aeruginosa biofilm.}, journal = {Microbial pathogenesis}, volume = {197}, number = {}, pages = {107079}, doi = {10.1016/j.micpath.2024.107079}, pmid = {39454803}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Pseudomonas aeruginosa/drug effects ; *Drug Synergism ; *Tobramycin/pharmacology ; *Anti-Bacterial Agents/pharmacology ; *Quorum Sensing/drug effects ; *Phenols/pharmacology ; *Rosmarinic Acid ; *Depsides/pharmacology ; *Resveratrol/pharmacology ; *Flavanones/pharmacology ; Curcumin/pharmacology ; Cinnamates/pharmacology ; Microbial Sensitivity Tests ; Virulence Factors ; }, abstract = {Bacteria coordinate gene expression in a cell density-dependent manner using a communication process called quorum sensing (QS). The expression of virulence factors, biofilm formation and enzyme production are examples of QS-regulated phenotypes that can interfere with food quality and safety. Due to the importance of these phenotypes, the inhibition of bacterial communication as an anti-virulence strategy is of great interest. This work aimed to evaluate the effect of phenolic compounds on the inhibition of biofilm formation by Pseudomonas aeruginosa PAO1, using concentrations that do not interfere in bacterial growth. The synergistic effect of rosmarinic acid, baicalein, curcumin and resveratrol with tobramycin and between the phenolics themselves was evaluated. The tested combinations proved to be a good strategy for reducing the dose of antibiotics used in treatments and obtaining satisfactory results against P. aeruginosa biofilms. The combination of the four compounds at the highest concentration (500 μM) completely inhibited biofilm formation. The obtained results contribute to understanding the effect of phenolic compounds on QS inhibition, which may help to define the mechanism of inhibition, in addition to expanding the biotechnological potential of these compounds for future applications in the food, pharmaceutical and medical fields.}, }
@article {pmid39454420, year = {2025}, author = {Wu, X and Yang, G and Guo, J and Zhuang, L}, title = {Redox potential shapes spatial heterogeneity of mixed-cultured electroactive biofilm treating wastewater.}, journal = {Bioelectrochemistry (Amsterdam, Netherlands)}, volume = {161}, number = {}, pages = {108836}, doi = {10.1016/j.bioelechem.2024.108836}, pmid = {39454420}, issn = {1878-562X}, mesh = {*Biofilms/growth &amp; development ; *Wastewater/microbiology ; *Oxidation-Reduction ; *Electrodes ; *Bioelectric Energy Sources/microbiology ; Microbiota ; Bacteria/metabolism/genetics ; Water Purification/methods ; Geobacter/physiology/metabolism ; }, abstract = {The core of bioelectrochemical systems (BESs) is electrochemically active microorganisms (EAMs), which exert spatial heterogeneity on electrode surface and influences BESs performance. Setting an optimal potential is an effective strategy for improving and optimizing BESs performance, however, how the electrode potential affects spatial structure of microbial community within anode biofilm is not known. Using a complex substrate-fed BES with a wastewater inoculum, this study investigated the community structure and composition of the stratified biofilm developed under the potential of -0.3 V, 0 V, +0.3 V and +0.6 V (vs. saturated calomel electrode) by freezing microtome method and high-throughput sequencing analysis. The spatial heterogeneity of biofilm community was found to be dependent on the electrode potential and a less stratified community structure was observed for +0.6 V than other potentials. Within the biofilms, the inner layers selected more Geobacter and the outer layers enriched more Acinetobacter and Serratia, potentially suggested a stratification of electron transfer pathway and metabolite-based interspecies communications. The results demonstrated the response of spatial heterogeneity of anode biofilm community to the change of electrode potential, which helps to understand the selectivity and enrichment of kinetically efficient anodic microbiome by electron potential.}, }
@article {pmid39452871, year = {2024}, author = {Mao, R and Zhao, Q and Lu, H and Yang, N and Li, Y and Teng, D and Hao, Y and Gu, X and Wang, J}, title = {The Marine Antimicrobial Peptide AOD with Intact Disulfide Bonds Has Remarkable Antibacterial and Anti-Biofilm Activity.}, journal = {Marine drugs}, volume = {22}, number = {10}, pages = {}, pmid = {39452871}, issn = {1660-3397}, support = {2023YFD1301103//National Key Research and Development Program/ ; 22322906D//Key Innovation Development Project of Hebei/ ; }, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Microbial Sensitivity Tests ; Animals ; *Disulfides/pharmacology/chemistry ; *Antimicrobial Peptides/pharmacology/chemistry ; Defensins/pharmacology/chemistry ; Ostreidae ; Staphylococcus epidermidis/drug effects ; }, abstract = {American Oyster Defensin (AOD) is a marine peptide that is derived from North American mussels. It has been demonstrated to exhibit potent antimicrobial activity and high safety in both in vitro and in vivo models. In this study, to facilitate synthesis, mutants of AOD with fewer disulfide bonds were designed and subjected to structural, antimicrobial, and anti-biofilm analysis. The antimicrobial activity of AOD-derived peptides decreased after reduction in the disulfide bond, and among its three derivatives, only AOD-1 inhibited very few bacteria with a MIC value of 64 μg/mL, whereas the others had no inhibitory effect on pathogenic bacteria. The findings demonstrated that full disulfide bonds are indispensable for bactericidal activity, with the α-helix playing a pivotal role in inhibiting bacterial membranes. Furthermore, the results of the ATP, ROS, membrane potential, and membrane fluidity assays demonstrated that intracellular ATP, reactive oxygen species, and membrane fluidity were all increased, while membrane potential was reduced. This indicated that AOD resulted in the impairment of membrane fluidity and induced metabolic disorders, ultimately leading to bacterial death. The inhibitory effect of AOD on the biofilm of S. epidermidis G-81 was determined through the crystal violet and confocal microscopy. The results demonstrated that AOD exhibited a notable inhibitory impact on the biofilm of S. epidermidis G-81. The minimum biofilm inhibitory concentration of AOD on S. epidermidis G-81 was 16 μg/mL, and the minimum biofilm scavenging concentration was 32 μg/mL, which exhibited superior efficacy compared to that of lincomycin. The inhibitory effect on the primary biofilm was 90.3%, and that on the mature biofilm was 82.85%, with a dose-dependent inhibition effect. Concurrently, AOD cleared intra-biofilm organisms and reduced the number of biofilm-holding bacteria by six orders of magnitude. These data indicate that disulfide bonds are essential to the structure and activity of AOD, and AOD may potentially become an effective dual-action antimicrobial and anti-biofilm agent.}, }
@article {pmid39452463, year = {2024}, author = {Pardo, A and Signoriello, A and Zangani, A and Messina, E and Gheza, S and Faccioni, P and Albanese, M and Lombardo, G}, title = {Home Biofilm Management in Orthodontic Aligners: A Systematic Review.}, journal = {Dentistry journal}, volume = {12}, number = {10}, pages = {}, pmid = {39452463}, issn = {2304-6767}, abstract = {Background. Transparent aligners are recently introduced orthodontic devices considered promising for the improvement of oral health conditions, in terms of faster treatment times and enhanced comfort, especially if compared with traditional fixed orthodontic therapy. This systematic review aimed to evaluate at-home protocols for proper oral hygiene and aligners cleaning during orthodontic treatment. Methods. A search was conducted using the following four databases: PubMed, Cochrane Library, Web of Science, and Scopus. The systematic review (registered as CRD 42024562215) followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines and included prospective studies, randomized controlled trials (RCTs), controlled clinical trials, and in vivo and ex vivo studies; they had to assess treatment with invisible orthodontics compared to treatment with fixed orthodontics, home oral hygiene, or aligner disinfection protocols. The evidence in the studies was evaluated for risk of bias using the RoB-2 (for RCTs and randomized crossover studies) and ROBINS-I tools (for observational studies). Results. Eleven studies were included in this systematic review: four RCTs, four crossover studies, and three cross-sectional observational studies. Seven studies considered patients undergoing orthodontic treatment, whereas four examined orthodontic aligners. The cleaning protocols of the aligners were evaluated based on the analysis of residual biofilm on the thermoplastic surfaces. Studies included were characterized by a low level of certainty, thus further evidence is needed. Conclusions. The most effective protocols entailed a combination of mechanical and chemical agents, suggesting that it is fundamental for patients undergoing aligner treatment to focus on individually tailored home oral hygiene protocols.}, }
@article {pmid39452253, year = {2024}, author = {De Plano, LM and Caratozzolo, M and Conoci, S and Guglielmino, SPP and Franco, D}, title = {Impact of Nutrient Starvation on Biofilm Formation in Pseudomonas aeruginosa: An Analysis of Growth, Adhesion, and Spatial Distribution.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {10}, pages = {}, pmid = {39452253}, issn = {2079-6382}, abstract = {Objectives: This study investigates the impact of nutrient availability on the growth, adhesion, and biofilm formation of Pseudomonas aeruginosa ATCC 27853 under static conditions. Methods: Bacterial behaviour was evaluated in nutrient-rich Luria-Bertani (LB) broth and nutrient-limited M9 media, specifically lacking carbon (M9-C), nitrogen (M9-N), or phosphorus (M9-P). Bacterial adhesion was analysed microscopically during the transition from reversible to irreversible attachment (up to 120 min) and during biofilm production/maturation stages (up to 72 h). Results: Results demonstrated that LB and M9 media supported bacterial growth, whereas nutrient-starved conditions halted growth, with M9-C and M9-N inducing stationary phases and M9-P leading to cell death. Fractal analysis was employed to characterise the spatial distribution and complexity of bacterial adhesion patterns, revealing that nutrient-limited conditions affected both adhesion density and biofilm architecture, particularly in M9-C. In addition, live/dead staining confirmed a higher proportion of dead cells in M9-P over time (at 48 and 72 h). Conclusions: This study highlights how nutrient starvation influences biofilm formation and bacterial dispersion, offering insights into the survival strategies of P. aeruginosa in resource-limited environments. These findings should contribute to a better understanding of biofilm dynamics, with implications for managing biofilm-related infections and industrial biofouling.}, }
@article {pmid39452242, year = {2024}, author = {Fauzia, KA and Effendi, WI and Alfaray, RI and Malaty, HM and Yamaoka, Y and Mifthussurur, M}, title = {Molecular Mechanisms of Biofilm Formation in Helicobacter pylori.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {10}, pages = {}, pmid = {39452242}, issn = {2079-6382}, support = {XXXX//Universitas Airlangga/ ; DK62813/NH/NIH HHS/United States ; 26640114, 221S0002, 16H06279, 15H02657 and 16H05191, 18KK0266, 19H03473, 21H00346, 22H02871, and 23K24133//Ministry of Education, Culture, Sports, Science, and Technology (MEXT) of Japan/ ; XXXXX//Japan Society for the Promotion of Science Institutional Program for Young Researcher Overseas Visits and the Strategic Funds for the Promotion of Science and Technology Agency (JST)/ ; xxxx//Japanese Government (MEXT) scholarship/ ; xxxx//Japan Agency for Medical Research and Development (AMED) [e-ASIA JRP]/ ; }, abstract = {BACKGROUND: Biofilm formation in Helicobacter pylori (H. pylori) helps bacteria survive antibiotic exposure and supports bacterial colonization and persistence in the stomach. Most of the published articles have focused on one aspect of the biofilm. Therefore, we conducted the current study to better understand the mechanism of biofilm formation, how the biofilm contributes to antibiotic resistance, and how the biofilm modifies the medication delivery mechanism.<br><br>METHODS: We conducted a literature review analysis of the published articles on the Helicobacter pylori biofilm between 1998 and 2024 from the PubMed database to retrieve eligible articles. After applying the inclusion and exclusion criteria, two hundred and seventy-three articles were eligible for our study.<br><br>RESULTS: The results showed that biofilm formation starts as adhesion and progresses through micro-colonies, maturation, and dispersion in a planktonic form. Moreover, specific genes modulate each phase of biofilm formation. Few studies have shown that mechanisms, such as quorum sensing and diffusible signal factors, enhance coordination among bacteria when switching from biofilm to planktonic states. Different protein expressions were also observed between planktonic and biofilm strains, and the biofilm architecture was supported by exopolysaccharides, extracellular DNA, and outer membrane vesicles.<br><br>CONCLUSIONS: This infrastructure is responsible for the increased survival of bacteria, especially in harsh environments or in the presence of antibiotics. Therefore, understanding the biofilm formation for H. pylori is crucial. This study illustrates biofilm formation in H. pylori to help improve the treatment of H. pylori infection.}, }
@article {pmid39452230, year = {2024}, author = {Cheng, J and Cho, JH and Suh, JW}, title = {Characterization of Human Breast Milk-Derived Limosilactobacillus reuteri MBHC 10138 with Respect to Purine Degradation, Anti-Biofilm, and Anti-Lipid Accumulation Activities.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {10}, pages = {}, pmid = {39452230}, issn = {2079-6382}, abstract = {Background: Human breast milk is a valuable source of potential probiotic candidates. The bacteria isolated from human breast milk play an important role in the development of the infant gut microbiota, exhibiting diverse biological functions. Methods: In this study, Limosilactobacillus reuteri MBHC 10138 isolated from breast milk was characterized in terms of its probiotic safety characteristics and potential efficacy in hyperuricemia, obesity, lipid liver, and dental caries, conditions which Korean consumers seek to manage using probiotics. Results: Strain MBHC 10138 demonstrated a lack of D-lactate and biogenic amine production as well as a lack of bile salt deconjugation and hemolytic activity. It also exhibited susceptibility to common antibiotics, tolerance to simulated oral-gastric-intestinal conditions, and superior biological activity compared to three L. reuteri reference strains, including KACC 11452 and MJ-1, isolated from feces, and a commercial strain isolated from human breast milk. Notably, L. reuteri MBHC 10138 showed high capabilities in assimilating guanosine (69.48%), inosine (81.92%), and adenosine (95.8%), strongly inhibited 92.74% of biofilm formation by Streptococcus mutans, and reduced lipid accumulation by 32% in HepG2 cells. Conclusions: These findings suggest that strain MBHC 10138, isolated from human breast milk, has potential to be developed as a probiotic for managing hyperuricemia, obesity, and dental caries after appropriate in vivo studies.}, }
@article {pmid39452196, year = {2024}, author = {Konaklieva, MI and Plotkin, BJ}, title = {Activity of Organoboron Compounds against Biofilm-Forming Pathogens.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {10}, pages = {}, pmid = {39452196}, issn = {2079-6382}, abstract = {Bacteria have evolved and continue to change in response to environmental stressors including antibiotics. Antibiotic resistance and the ability to form biofilms are inextricably linked, requiring the continuous search for alternative compounds to antibiotics that affect biofilm formation. One of the latest drug classes is boron-containing compounds. Over the last several decades, boron has emerged as a prominent element in the field of medicinal chemistry, which has led to an increasing number of boron-containing compounds being considered as potential drugs. The focus of this review is on the developments in boron-containing organic compounds (BOCs) as antimicrobial/anti-biofilm probes and agents.}, }
@article {pmid39452124, year = {2024}, author = {Pechroj, S and Kaewkod, T and Sattayawat, P and Inta, A and Suriyaprom, S and Yata, T and Tragoolpua, Y and Promputtha, I}, title = {Multifunctional Nanoemulsified Clinacanthus nutans Extract: Synergistic Anti-Pathogenic, Anti-Biofilm, Anti-Inflammatory, and Metabolic Modulation Effects against Periodontitis.}, journal = {Biology}, volume = {13}, number = {10}, pages = {}, pmid = {39452124}, issn = {2079-7737}, support = {Fundamental Research Funds; FF66/038//Chiang Mai University/ ; }, abstract = {This study investigates the therapeutic potential of Clinacanthus nutans extracts, focusing on the 95% ethanol (95E) extract and its nanoemulsified form, against oral pathogens and their bioactive effects. The findings demonstrate potent antibacterial activity against Streptococcus mutans and Staphylococcus aureus, essential for combating periodontal diseases, and significant anti-biofilm properties crucial for plaque management. Additionally, the extracts exhibit promising inhibitory effects on α-glucosidase enzymes, indicating potential for diabetes management through glucose metabolism regulation. Their anti-inflammatory properties, evidenced by reduced nitric oxide production, underscore their potential for treating oral infections and inflammation. Notably, the nanoemulsified 95E extract shows higher efficiency than the conventional extract, suggesting a multifunctional treatment approach for periodontal issues and metabolic disorders. These results highlight the enhanced efficacy of the nanoemulsified extract, proposing it as an effective treatment modality for periodontal disease in diabetic patients. This research offers valuable insights into the development of innovative drug delivery systems using natural remedies for improved periodontal care in diabetic populations.}, }
@article {pmid39451698, year = {2024}, author = {Lovecchio, N and Giuseppetti, R and Bertuccini, L and Columba-Cabezas, S and Di Meo, V and Figliomeni, M and Iosi, F and Petrucci, G and Sonnessa, M and Magurano, F and D'Ugo, E}, title = {Hydrocarbonoclastic Biofilm-Based Microbial Fuel Cells: Exploiting Biofilms at Water-Oil Interface for Renewable Energy and Wastewater Remediation.}, journal = {Biosensors}, volume = {14}, number = {10}, pages = {}, pmid = {39451698}, issn = {2079-6374}, support = {ISS: 4 ISS20-cd5d8b022b4e//Istituto Superiore di Sanit&#xe0;/ ; }, mesh = {*Biofilms ; *Bioelectric Energy Sources ; *Wastewater/microbiology ; *Hydrocarbons/metabolism ; *Renewable Energy ; Electrodes ; Biodegradation, Environmental ; }, abstract = {Microbial fuel cells (MFCs) represent a promising technology for sustainable energy generation, which leverages the metabolic activities of microorganisms to convert organic substrates into electrical energy. In oil spill scenarios, hydrocarbonoclastic biofilms naturally form at the water-oil interface, creating a distinct environment for microbial activity. In this work, we engineered a novel MFC that harnesses these biofilms by strategically positioning the positive electrode at this critical junction, integrating the biofilm's natural properties into the MFC design. These biofilms, composed of specialized hydrocarbon-degrading bacteria, are vital in supporting electron transfer, significantly enhancing the system's power generation. Next-generation sequencing and scanning electron microscopy were used to characterize the microbial community, revealing a significant enrichment of hydrocarbonoclastic Gammaproteobacteria within the biofilm. Notably, key genera such as Paenalcaligenes, Providencia, and Pseudomonas were identified as dominant members, each contributing to the degradation of complex hydrocarbons and supporting the electrogenic activity of the MFCs. An electrochemical analysis demonstrated that the MFC achieved a stable power output of 51.5 μW under static conditions, with an internal resistance of about 1.05 kΩ. The system showed remarkable long-term stability, which maintained consistent performance over a 5-day testing period, with an average daily energy storage of approximately 216 mJ. Additionally, the MFC effectively recovered after deep discharge cycles, sustaining power output for up to 7.5 h before requiring a recovery period. Overall, the study indicates that MFCs based on hydrocarbonoclastic biofilms provide a dual-functionality system, combining renewable energy generation with environmental remediation, particularly in wastewater treatment. Despite lower power output compared to other hydrocarbon-degrading MFCs, the results highlight the potential of this technology for autonomous sensor networks and other low-power applications, which required sustainable energy sources. Moreover, the hydrocarbonoclastic biofilm-based MFC presented here offer significant potential as a biosensor for real-time monitoring of hydrocarbons and other contaminants in water. The biofilm's electrogenic properties enable the detection of organic compound degradation, positioning this system as ideal for environmental biosensing applications.}, }
@article {pmid39451421, year = {2024}, author = {Didouh, H and Khurshid, H and Hadj Meliani, M and Suleiman, RK and Umoren, SA and Bouhaik, IS}, title = {Exploring NRB Biofilm Adhesion and Biocorrosion in Oil/Water Recovery Operations Within Pipelines.}, journal = {Bioengineering (Basel, Switzerland)}, volume = {11}, number = {10}, pages = {}, pmid = {39451421}, issn = {2306-5354}, abstract = {Microbially influenced corrosion represents a critical challenge to the integrity and durability of carbon steel infrastructure, particularly in environments conducive to biofilm formation by nitrate-reducing bacteria (NRB). This study investigated the impact of NRB biofilms on biocorrosion processes within oil/water recovery operations in Algerian pipelines. A comprehensive suite of experimental and analytical techniques, including microbial analysis, gravimetric methods, and surface characterization, were employed to elucidate the mechanisms of microbially influenced corrosion (MIC). Weight loss measurements revealed that carbon steel samples exposed to injection water exhibited a corrosion rate of 0.0125 mm/year, significantly higher than the 0.0042 mm/year observed in crude oil environments. The microbial analysis demonstrated that injection water harbored an average of (4.4 ± 0.56) × 10[6] cells/cm[2] for sessile cells and (3.1 ± 0.25) × 10[5] CFU/mL for planktonic cells, in stark contrast to crude oil, which contained only (2.4 ± 0.34) × 10[3] cells/cm[2] for sessile cells and (4.5 ± 0.12) × 10[2] CFU/mL for planktonic cells, thereby highlighting the predominant role of injection water in facilitating biofilm formation. Contact angle measurements of injection water on carbon showed 45° ± 2°, compared to 85° ± 4° for crude oil, suggesting an increased hydrophilicity associated with enhanced biofilm adhesion. Scanning electron microscopy further confirmed the presence of thick biofilm clusters and corrosion pits on carbon steel exposed to injection water, while minimal biofilm and corrosion were observed in the crude oil samples.}, }
@article {pmid39451375, year = {2024}, author = {Petričević, GK and Perčinić, A and Budimir, A and Sesar, A and Anić, I and Bago, I}, title = {Comparison of a Novel Modality of Erbium-Doped Yttrium Aluminum Garnet Laser-Activated Irrigation and Ultrasonic Irrigation against Mature Enterococcus faecalis Biofilm-An In Vitro Study.}, journal = {Bioengineering (Basel, Switzerland)}, volume = {11}, number = {10}, pages = {}, pmid = {39451375}, issn = {2306-5354}, support = {5303//Croatian Science Foundation/ ; }, abstract = {In this in vitro study, we aimed to evaluate and compare the antibacterial efficacy of a novel erbium-doped yttrium aluminum garnet laser modality, shock wave enhanced emission of photoacoustic streaming (SWEEPS), ultrasonically activated irrigation (UAI), and single needle irrigation (SNI) against old bacterial biofilm. A two-week-old Enterococcus faecalis biofilm was cultivated on transversal dentinal discs made from the middle third of the roots of single-rooted, single-canal premolars. Biofilm growth was confirmed using scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). The dentine samples were randomly distributed into three experimental groups and one control group based on the irrigation protocol used: Group 1, SWEEPS; Group 2, UAI; and Group 3, SNI. The root canals were irrigated with a 3% sodium hypochlorite solution. Antibacterial efficacy was evaluated quantitatively through bacterial culture and qualitatively through CLSM and SEM. Both SWEEPS and UAI demonstrated a statistically significant reduction in Enterococcus faecalis colony-forming units (CFUs) (p < 0.001), while SNI did not show a statistically significant reduction (p = 0.553). No significant difference was observed between the efficacy of SWEEPS and UAI (p > 0.05). The SWEEPS and UAI techniques were equally effective in eliminating mature E. faecalis biofilm.}, }
@article {pmid39450290, year = {2024}, author = {Ferreira, M and Pinto, M and Aires-da-Silva, F and Bettencourt, A and Gaspar, MM and Aguiar, SI}, title = {Rifabutin: a repurposed antibiotic with high potential against planktonic and biofilm staphylococcal clinical isolates.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1475124}, pmid = {39450290}, issn = {1664-302X}, abstract = {Staphylococcus aureus poses a significant threat as an opportunistic pathogen in humans, and animal medicine, particularly in the context of hospital-acquired infections (HAIs). Effective treatment is a significant challenge, contributing substantially to the global health burden. While antibiotic therapy remains the primary approach for staphylococcal infections, its efficacy is often compromised by the emergence of resistant strains and biofilm formation. The anticipated solution is the discovery and development of new antibacterial agents. However, this is a time consuming and expensive process with limited success rates. One potential alternative for addressing this challenge is the repurposing of existing antibiotics. This study investigated the potential of rifabutin (RFB) as a repurposed antibiotic for treating S. aureus infections. The minimum inhibitory concentration (MIC) of rifabutin was assessed by the broth microdilution method, in parallel to vancomycin, against 114 clinical isolates in planktonic form. The minimum biofilm inhibitory concentration (MBIC50) was determined by an adaptation of the broth microdilution method, followed by MTT assay, against a subset of selected 40 clinical isolates organized in biofilms. The study demonstrated that RFB MIC ranged from 0.002 to 6.250 μg/mL with a MIC50 of 0.013 μg/mL. RFB also demonstrated high anti-biofilm activity in the subset of 40 clinical isolates, with confirmed biofilm formation, with no significant MBIC50 differences observed between the MSSA and MRSA strains, in contrast to that observed for the VAN. These results highlight the promising efficacy of RFB against staphylococcal clinical isolates with different resistance patterns, whether in planktonic and biofilm forms.}, }
@article {pmid39449953, year = {2024}, author = {Mathew, MZ and Arthanari, A and Ganesh, S and Naseef Pathoor, N and Ramalingam, K and Ravindran, V}, title = {Evaluating the Efficacy of Actinidia deliciosa (Kiwi Fruit) Extract in Inhibiting Pseudomonas aeruginosa Biofilm Formation: An In Vitro Study With Therapeutic Implications.}, journal = {Cureus}, volume = {16}, number = {9}, pages = {e70082}, pmid = {39449953}, issn = {2168-8184}, abstract = {Background Gram-negative Pseudomonas aeruginosa is a common bacteria that is well-known for its capacity to build biofilms, which are organized cell communities encased in a self-produced polymeric matrix. Treating infections becomes more challenging due to biofilms' capacity to provide immunity and resistance to antibiotics. The search for novel anti-biofilm agents has gained significant momentum, and the diverse range of bioactive compounds found in natural products offers a promising avenue. Rich in vitamins, antioxidants, and various phytochemicals, Actinidia deliciosa (kiwi fruit) has demonstrated potential as an antibacterial agent. Aim of the study This study aims to assess the efficacy of A. deliciosa extract in inhibiting biofilm formation by P. aeruginosa in vitro, providing valuable insights into its potential as a natural therapeutic agent for preventing recurrent bacterial infections. Materials and methodology The antibacterial and antibiofilm properties of A. deliciosa (kiwi fruit) methanolic extract were assessed in this study against P. aeruginosa (PAO1). The fruit was gathered, examined by a botanist for authenticity, and then cold macerated in methanol to create an extract. A two-fold broth dilution procedure was used to calculate the minimum inhibitory concentration (MIC), and agar well-diffusion was used to evaluate the antimicrobial activity. Pyocyanin pigment quantification was carried out after the extract was applied, and the antibiofilm impact was evaluated using a crystal violet assay. GraphPad Prism (GraphPad Software, San Diego, CA) was used for statistical analysis. Results Based on our findings, A. deliciosa was shown to have significant antibacterial and antibiofilm properties against P. aeruginosa (PAO1). At 5 mg/mL, the methanolic extract of A. deliciosa exhibited antibacterial activity with an 8 mm zone of inhibition and suppressed PAO1 growth. At 2.5 mg/mL and 1.25 mg/mL doses, PAO1 significantly decreased the production of biofilms by 60% and 29%, respectively. In addition, pyocyanin pigment synthesis was decreased by 30% and 9.25%, respectively, at sub-MIC doses of 2.5 mg/mL and 1.25 mg/mL. When evaluated at 2.5 mg/mL, the extract did not, however, appreciably affect bacterial growth. Conclusion This study enhances the understanding of antibiotic resistance, alternative treatments, and pathogenic microbes. The in vitro findings suggest that A. deliciosa fruit extract may inhibit pyocyanin production in PAO1. Further research with different formulations is recommended to explore its anti-biofilm properties and potential pharmacological applications.}, }
@article {pmid39449882, year = {2024}, author = {Meredith, K and Coleborn, MM and Forbes, LE and Metcalf, DG}, title = {Assessment of the Antibiofilm Performance of Silver-Containing Wound Dressings: A Dual-Species Biofilm Model.}, journal = {Cureus}, volume = {16}, number = {9}, pages = {e70086}, pmid = {39449882}, issn = {2168-8184}, abstract = {Background It is commonly accepted that microorganisms found within hard-to-heal wounds are present in biofilm form. Biofilms are often polymicrobial in nature, which increases their virulence and tolerance to antimicrobial agents. The aim of this study was to compare the antibiofilm activity of silver-containing antimicrobial wound dressings in a dual-species simulated wound biofilm model. Materials and methods Four silver-containing wound dressings were evaluated in vitro: Aquacel[®] Ag+ Extra™ dressing, KerraContact[®] Ag dressing, Durafiber* Ag dressing, and UrgoClean Ag dressing. Each dressing was applied to a simulated wound assembly containing biofilm-gauze inoculated with Klebsiella pneumoniae and methicillin-resistant Staphylococcus aureus (MRSA). Each biofilm-inoculated gauze was incubated at 35±3[º]C for 6, 24, 48 and 72 hours. Enumeration of surviving biofilm bacteria at each time point was performed in triplicate for each test dressing and its equivalent control. Results Aquacel[®] Ag+ Extra™ dressing was observed to reduce the biofilm population within 24 hours with a >4 log10 kill observed for K. pneumoniae and >6 log10 for MRSA from an initial biofilm challenge of 4.16×10[9] CFU/mL. This kill rate was sustained for the duration of the challenge period, with Aquacel[®] Ag+ Extra™ dressing reducing the biofilm population to non-detectable levels (<30 Colony Forming Units (CFU) per test) by 72 hours for K. pneumoniae and by 48 hours for MRSA. KerraContact[®] Ag dressing demonstrated an initial reduction at 6 hours of ~2 log10 in both K. pneumoniae and MRSA. Durafiber* Ag dressing exhibited a slight, gradual reduction in biofilm population over the course of the test period, reducing each challenge organism by ~2.5 log10 by 72 hours. UrgoClean Ag was shown to have little to no impact on the dual-species biofilm with levels remaining similar or greater than that recovered prior to dressing application. The no-dressing biofilm-colonised gauze control demonstrated that the biofilm bacteria remained viable throughout the test period and species population proportionality was maintained. Conclusion Using a dual-species simulated wound biofilm model comprising the pathogens K. pneumoniae and MRSA, Aquacel[®] Ag+ Extra™ dressing demonstrated significantly greater antibiofilm activity than the other silver-containing dressings. The enhanced antibiofilm activity of Aquacel[®] Ag+ Extra™ dressing in this study may be attributed to the additional antibiofilm agents, ethylenediaminetetraacetic acid and benzethonium chloride, contained within the dressing.}, }
@article {pmid39449220, year = {2025}, author = {Bose, S and Das, SK}, title = {Biofilm Microenvironment-Sensitive Anti-Virulent and Immunomodulatory Nano-on-Nanodroplets to Combat Refractory Biofilm Infection Through Toxin Neutralization and Phagocytosis.}, journal = {Advanced healthcare materials}, volume = {14}, number = {2}, pages = {e2403528}, doi = {10.1002/adhm.202403528}, pmid = {39449220}, issn = {2192-2659}, support = {STBT-13015/3/2024-WBSCST SEC//Department of Science and Technology and Biotechnology, Govt. of West Bengal/ ; IICBP07//Institutional project fund/ ; }, mesh = {*Biofilms/drug effects ; *Staphylococcus aureus/drug effects/physiology ; Animals ; *Phagocytosis/drug effects ; Mice ; Staphylococcal Infections/drug therapy/immunology ; Anti-Bacterial Agents/chemistry/pharmacology ; Nanoparticles/chemistry ; Bacterial Toxins/chemistry ; Humans ; Immunomodulating Agents/chemistry/pharmacology ; Macrophages/drug effects/immunology ; }, abstract = {Biofilm-associated wound infection is principally perceived as the bacterial defense mechanism that hinders antibiotic penetration, causes toxin impairment, and suppresses the immunological responses of the host immune system. Several antibiofilm agents have been developed, but the least of these agents can simultaneously cornerstone on the biofilm-associated immunosuppression and bacterial toxin-induced cellular dysfunction. Inspired by the fusogenic property of nanodroplets and immunomodulatory functions of metal nanoparticles, biofilm targeted anti-virulent immunomodulatory cationic nanoparticle shelled nanodroplets (C-AgND) is fabricated to completely disintegrate and eradicate the Staphylococcus aureus (S. aureus) biofilm. The specific binding of C-AgND neutralizes the negatively charged EPS layer, causing their destabilization followed by penetration of the nanoformulation into the biofilm matrix, killing the persister cells. Consequently, C-AgND eliminates the virulence property of the S. aureus biofilm through α-hemolysin neutralization. C-AgND promotes a strong immunomodulatory effect by polarizing macrophages into their M1 phenotype to induce phagocytosis of the disintegrated biofilm-released residual cells, rejuvenating the host's innate immune responses for the complete eradication of the biofilm. Moreover, the ex vivo skin wound infection model illustrates an excellent biofilm eradication efficacy of C-AgND in comparison to the commercial ones, rendering them to be a promising replacement of existing antibiofilm agents in clinical application.}, }
@article {pmid39449168, year = {2024}, author = {Hoerler, SB and Mueller, EB and Murray, WR and Zhou, MX}, title = {Survey on Patient Perception of At-Home Bacterial Biofilm Control in Relation to Peri-Implant Soft Tissue Health.}, journal = {International journal of dental hygiene}, volume = {}, number = {}, pages = {}, doi = {10.1111/idh.12860}, pmid = {39449168}, issn = {1601-5037}, support = {UL1 TR002377/TR/NCATS NIH HHS/United States ; }, abstract = {OBJECTIVE: Bacterial biofilm control around dental implants is critical for the health of the peri-implant soft tissue and longevity of dental implants. The patient's role in regular biofilm removal around dental implants is just as important as that of the dental hygienist. The purpose of this study is to identify the relationship between at-home dental implant care and patients' perceptions of peri-implant soft tissue health.<br><br>METHODS: A 15-item paper survey was distributed to adult patients undergoing professional dental hygiene maintenance at a specialty dental practice within a 3-month period and had at least one dental implant. Survey items included participant demographics, patient-reported adjunctive aids for dental implants and patient perceptions of dental implant oral hygiene practices and peri-implant soft tissue health.<br><br>RESULTS: There was a statistical difference between time spent cleaning dental implants and peri-implant soft tissue health. An association was found between patients who reported spending more time cleaning their dental implants and less bleeding (p&#x2009;=&#x2009;0.046/54%), gingival inflammation (p&#x2009;=&#x2009;0.026/58%) and gingival tissue redness (p&#x2009;=&#x2009;0.036/53%). Additionally, patients who more frequently underwent professional dental hygiene maintenance perceived less gingival inflammation (p&#x2009;=&#x2009;0.001/66%).<br><br>CONCLUSION: To promote peri-implant soft tissue health and reduce oral biological complications, best practice guidelines should be implemented, including optimal at-home dental implant care and regular professional dental hygiene maintenance.}, }
@article {pmid39449164, year = {2024}, author = {Majumder, S and Coull, BA and Welch, JLM and Riviere, PJ and Dewhirst, FE and Starr, JR and Lee, KH}, title = {Multivariate Cluster Point Process to Quantify and Explore Multi-Entity Configurations: Application to Biofilm Image Data.}, journal = {Statistics in medicine}, volume = {43}, number = {28}, pages = {5446-5460}, doi = {10.1002/sim.10261}, pmid = {39449164}, issn = {1097-0258}, support = {R01 DE016937/DE/NIDCR NIH HHS/United States ; ES000002/GF/NIH HHS/United States ; P30 ES000002/ES/NIEHS NIH HHS/United States ; R01 DE022586/DE/NIDCR NIH HHS/United States ; R01 GM126257/GM/NIGMS NIH HHS/United States ; DE027486/GF/NIH HHS/United States ; DE026872/GF/NIH HHS/United States ; DE016937/GF/NIH HHS/United States ; DE022586/GF/NIH HHS/United States ; R03 DE027486/DE/NIDCR NIH HHS/United States ; GM126257/GF/NIH HHS/United States ; R21 DE026872/DE/NIDCR NIH HHS/United States ; }, mesh = {Multivariate Analysis ; Cluster Analysis ; Humans ; *Dental Plaque/diagnostic imaging/microbiology ; *Biofilms/classification ; *Bacteria/classification/isolation &amp; purification ; Models, Statistical ; Computer Simulation ; }, abstract = {Clusters of similar or dissimilar objects are encountered in many fields. Frequently used approaches treat each cluster's central object as latent. Yet, often objects of one or more types cluster around objects of another type. Such arrangements are common in biomedical images of cells, in which nearby cell types likely interact. Quantifying spatial relationships may elucidate biological mechanisms. Parent-offspring statistical frameworks can be usefully applied even when central objects ("parents") differ from peripheral ones ("offspring"). We propose the novel multivariate cluster point process (MCPP) to quantify multi-object (e.g., multi-cellular) arrangements. Unlike commonly used approaches, the MCPP exploits locations of the central parent object in clusters. It accounts for possibly multilayered, multivariate clustering. The model formulation requires specification of which object types function as cluster centers and which reside peripherally. If such information is unknown, the relative roles of object types may be explored by comparing fit of different models via the deviance information criterion (DIC). In simulated data, we compared a series of models' DIC; the MCPP correctly identified simulated relationships. It also produced more accurate and precise parameter estimates than the classical univariate Neyman-Scott process model. We also used the MCPP to quantify proposed configurations and explore new ones in human dental plaque biofilm image data. MCPP models quantified simultaneous clustering of Streptococcus and Porphyromonas around Corynebacterium and of Pasteurellaceae around Streptococcus and successfully captured hypothesized structures for all taxa. Further exploration suggested the presence of clustering between Fusobacterium and Leptotrichia, a previously unreported relationship.}, }
@article {pmid39448367, year = {2024}, author = {Saha, U and Jadhav, SV and Pathak, KN and Saroj, SD}, title = {Screening of Klebsiella pneumoniae isolates reveals the spread of strong biofilm formers and class 1 integrons.}, journal = {Journal of applied microbiology}, volume = {135}, number = {11}, pages = {}, doi = {10.1093/jambio/lxae275}, pmid = {39448367}, issn = {1365-2672}, support = {SR/PURSE/2023/181//DST/ ; }, mesh = {*Biofilms/growth &amp; development ; *Klebsiella pneumoniae/genetics/isolation &amp; purification/drug effects ; *Integrons/genetics ; Humans ; *Klebsiella Infections/microbiology ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology ; India ; Virulence/genetics ; Drug Resistance, Multiple, Bacterial/genetics ; beta-Lactamases/genetics ; Bacterial Proteins/genetics ; Drug Resistance, Bacterial/genetics ; }, abstract = {AIMS: Klebsiella pneumoniae is a Gram-negative bacterium that can colonize, penetrate, and cause infections at several human anatomical locations. The emergence of hypervirulent K. pneumoniae and its ability to evade the immune system and develop antibiotic resistance has made it a key concern in the healthcare industry. The hypervirulent variants are increasingly involved in community-acquired infections. Therefore, it is pertinent to understand the biofilm formation potential among the clinical isolates.<br><br>METHODS AND RESULTS: We acquired 225 isolates of K. pneumoniae from the Department of Microbiology, Symbiosis University Hospital and Research Centre (SUHRC), Pune, India, over 1 year from March 2022 to March 2023, and evaluated antimicrobial susceptibility, hypermucoviscous phenotype, virulence, and antimicrobial-resistant gene distribution in K. pneumoniae isolates and established a correlation between antimicrobial resistance and integrons. Most isolates were strong biofilm formers (76%). The isolates harbored one or more carbapenemase/beta-lactamase-encoding gene combinations. Hypermucoviscous (HMKP) isolates had considerably greater positive rates for iutA, magA, K2 serotype, rmpA, and rmpA2 than non-HMKP isolates. Isolates carrying integrons (43%) showed significantly more antibiotic resistance.<br><br>CONCLUSION: The study reveals spread of strong biofilm formers with extensive virulence and antimicrobial-resistant genes, and integrons responsible for multidrug resistance among the clinical isolates of K. pneumoniae in Pune, India, posing a threat to the public health and necessitating close surveillance, accurate diagnosis, control, and therapeutic management of infections.}, }
@article {pmid39448151, year = {2025}, author = {Choi, J and Park, S and Chang, Y}, title = {Development and application of a bacteriophage cocktail for Shigella flexneri biofilm inhibition on the stainless steel surface.}, journal = {Food microbiology}, volume = {125}, number = {}, pages = {104641}, doi = {10.1016/j.fm.2024.104641}, pmid = {39448151}, issn = {1095-9998}, mesh = {*Biofilms/growth &amp; development ; *Stainless Steel ; *Bacteriophages/physiology ; *Shigella flexneri/virology/growth &amp; development/physiology ; Sewage/virology/microbiology ; Food Contamination/prevention &amp; control/analysis ; Biological Control Agents/pharmacology ; Food Microbiology ; Caudovirales/physiology ; }, abstract = {Food contamination and biofilm formation by Shigella in food processing facilities are major causes of acute gastrointestinal infection and mortality in humans. Bacteriophages (phages) are promising alternatives to antibiotics in controlling plankton and biofilms in food matrices. This study isolated two novel phages, S2_01 and S2_02, with lytic activity against various Shigella spp. From sewage samples. Transmission electron microscopy revealed that phages S2_01 and S2_02 belonged to the Caudovirales order. On characterizing their lytic ability, phage S2_01 initially exhibited relatively weak antibacterial activity, while phage S2_02 initially displayed rapid antibacterial activity after phage application. A combination of these phages in a 1:9 ratio was selected, as it has been suggested to elicit the most rapid and sustained lysis ability for up to 24 h. It demonstrated lytic activity against various foodborne pathogens, including six Shigella spp. The phage cocktail exhibited biofilm inhibition and disruption abilities of approximately 79.29% and 42.55%, respectively, after 24 h in a 96-well microplate. In addition, inhibition (up to 23.42%) and disruption (up to 19.89%) abilities were also observed on stainless steel surfaces, and plankton growth was also significantly suppressed. Therefore, the phage cocktail formulated in this study displays great potential as a biological control agent in improving food safety against biofilms and plankton.}, }
@article {pmid39447661, year = {2024}, author = {Silva, RTPD and Rocha, IV and Dantas, TF and Silva, JDS and Costa Júnior, SDD and Luz, ACO and Moreno, M and Leal-Balbino, TC and Araújo Lima, AV and Silva, EGD and Coutinho, HDM and Oliveira, MBM}, title = {Emergence and spread of resistant and biofilm-forming Acinetobacter baumannii in critically ill COVID-19 patients.}, journal = {Microbial pathogenesis}, volume = {197}, number = {}, pages = {107078}, doi = {10.1016/j.micpath.2024.107078}, pmid = {39447661}, issn = {1096-1208}, mesh = {Humans ; *Acinetobacter baumannii/drug effects/genetics ; *Biofilms/drug effects/growth &amp; development ; *COVID-19/microbiology ; *Acinetobacter Infections/microbiology/drug therapy ; *Critical Illness ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; *SARS-CoV-2/genetics/drug effects ; Coinfection/microbiology/virology ; Drug Resistance, Multiple, Bacterial/genetics ; Cross Infection/microbiology ; Drug Resistance, Bacterial/genetics ; Middle Aged ; Male ; Female ; }, abstract = {The COVID-19 pandemic has raised concerns beyond the viral infection itself. Bacterial co-infections, particularly those involving Acinetobacter baumannii, have become a significant worry in critically ill COVID-19 patients. A. baumannii is an opportunistic pathogen that can cause nosocomial infections, especially in patients with compromised immune systems. This study investigated 36 A. baumannii isolates obtained from COVID-19 patients during a concurrent outbreak. The isolates were collected over two years through routine medical requests sent to the Clinical Microbiology laboratory. Identification of the strains was confirmed through biochemical tests, the Phoenix BD® Automated Microbiology System, and MALDI-TOF Mass Spectrometry. The study assessed the antimicrobial sensitivity of the isolates, with a specific focus on resistance to the beta-lactam group as well as aminoglycosides. The presence of specific antibiotic resistance genes (blaOXA-23, -24, -51 and -58, blaKPC, blaSHV, blaIMP, blaVIM, aac(6')-Ib, ant(3″)-Ia, and aph(3')-Ia) was investigated using PCR and Sanger DNA sequencing. Biofilm-forming capabilities of the isolates were also evaluated. The findings revealed diverse resistance profiles, with a high prevalence of resistant strains, including resistance to carbapenems. Genetic analysis suggested potential clonal spread of certain strains within the hospital setting. Moreover, a significant proportion of the isolates demonstrated strong biofilm-forming abilities, which can enhance persistence and antibiotic resistance. In conclusion, this study highlights the need for vigilant monitoring and targeted interventions to address bacterial co-infections in COVID-19 patients. The diversity in resistance patterns, potential clonal spread, and robust biofilm-forming abilities among A. baumannii isolates underscore the importance of addressing this issue to better manage and treat critically ill COVID-19 patients.}, }
@article {pmid39447656, year = {2024}, author = {Rajab, AAH and Fahmy, EK and Esmaeel, SE and Yousef, N and Askoura, M}, title = {In vitro and in vivo assessment of the competence of a novel lytic phage vB_EcoS_UTEC10 targeting multidrug resistant Escherichia coli with a robust biofilm eradication activity.}, journal = {Microbial pathogenesis}, volume = {197}, number = {}, pages = {107058}, doi = {10.1016/j.micpath.2024.107058}, pmid = {39447656}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Escherichia coli/virology ; Animals ; *Drug Resistance, Multiple, Bacterial ; *Escherichia coli Infections/therapy/microbiology ; Mice ; *Phage Therapy ; *Genome, Viral ; Bacteriophages/genetics/physiology/isolation &amp; purification ; Coliphages/genetics/physiology ; Humans ; Bacterial Load ; Open Reading Frames ; Bacteriolysis ; Anti-Bacterial Agents/pharmacology ; Disease Models, Animal ; Mice, Inbred BALB C ; }, abstract = {Escherichia coli (E. coli) is a leading cause of human infections worldwide and is considered a major cause of nosocomial infections, sepsis, meningitis and diarrhea. Lately, there has been an alarming increase in the incidence of antimicrobial resistance among clinical E. coli isolates. In the current study, a novel bacteriophage (phage) vB_EcoS_UTEC10 was isolated and characterized. The isolated phage showed high stability over wide temperature and pH ranges beside its promising bacteriolytic activity against multidrug resistant (MDR) E. coli isolates. In addition, vB_EcoS_UTEC10 showed a marked antibiofilm capability against mature E. coli biofilms. Genomic investigation revealed that vB_EcoS_UTEC10 has a double stranded DNA genome that consists of 44,772 bp comprising a total of 73 open reading frames (ORFs), out of which 35 ORFs were annotated as structural or functional proteins, and none were related to antimicrobial resistance or lysogeny. In vivo investigations revealed a promising bacteriolytic activity of vB_EcoS_UTEC10 against MDR E. coli which was further supported by a significant reduction in bacterial load in specimens collected from the phage-treated mice. Histopathology examination demonstrated minimal signs of inflammation and necrosis in the tissues of phage-treated mice compared to the degenerative tissue damage observed in untreated mice. In summary, the present findings suggest that vB_EcoS_UTEC10 has a remarkable ability to eradicate MDR E. coli infections and biofilms. These findings could be further invested for the development of targeted phage therapies that offer a viable alternative to traditional antibiotics against resistant E. coli.}, }
@article {pmid39447583, year = {2024}, author = {Zhang, Y and Wente, N and Leimbach, S and Klocke, D and Tellen, A and Nitz, J and Nankemann, F and Louton, H and Krömker, V}, title = {In vitro capsule or biofilm formation of Streptococcus uberis and bacteriological cure of bovine mastitis.}, journal = {Tierarztliche Praxis. Ausgabe G, Grosstiere/Nutztiere}, volume = {52}, number = {5}, pages = {264-270}, doi = {10.1055/a-2410-1465}, pmid = {39447583}, issn = {2567-5834}, mesh = {Animals ; Cattle ; *Mastitis, Bovine/microbiology/drug therapy ; *Biofilms/drug effects/growth &amp; development ; Female ; *Streptococcus/drug effects/isolation &amp; purification ; *Anti-Bacterial Agents/pharmacology/therapeutic use ; *Streptococcal Infections/veterinary/microbiology/drug therapy ; *Virulence Factors ; Bacterial Capsules ; }, abstract = {OBJECTIVE: The relationship between the in vitro detected virulence factors biofilm and capsule formation of Streptococcus (S.) uberis isolates of clinical mastitis in dairy cows and the bacteriological cure rate after antibiotic therapy was investigated in order to better understand the importance of these virulence factors for the bacteriological cure rate.<br><br>MATERIAL AND METHODS: A total of 111 clinical mastitis (CM) cases were collected, in which S. uberis was bacteriologically detected. All mastitis cases were treated in accordance with the approval conditions of the antibiotic udder tubes used. Individual cow information including age, number of lactations, current lactation mastitis and antimicrobial treatment received was recorded. The microtiter plate test was used to detect biofilm formation and Anthony capsule staining was used to detect capsular capacity. Statistical analyses were performed to characterize the correlation between in vitro virulence factors and bacteriological cure (BC) rate.<br><br>RESULTS: 30.5% (n=29) of the S. uberis isolates of bacteriologically cured cases and 34.5% (n=10) of the isolates of bacteriologically non-cured mastitis cases were found to have the ability to produce capsules in vitro. 70.7% (n=58) of the S. uberis isolates from bacteriologically cured mastitis cases had the ability to produce biofilm in vitro, whereas 58.6% (n=17) of the isolates of non-cured mastitis cases showed ability in producing biofilm. No correlation was found between the in vitro ability of S. uberis to form capsules and biofilms and the BC rate after antibiotic treatment of bovine mastitis.<br><br>CONCLUSION(S): The present work has shown that the investigated in vitro virulence factors are not associated with the BC after antibiotic therapy. Further studies on the role of S. uberis virulence factors are needed to complete the missing knowledge on the difficulties in curing S. uberis mastitis.<br><br>CLINICAL RELEVANCE: This study is of great clinical relevance since it enhances the understanding of the occurrence of BC in S. uberis mastitis cases. The investigated virulence factors are often addressed as possible reasons for therapy failure, although respective scientific studies are missing.}, }
@article {pmid39447462, year = {2025}, author = {Xu, H and Jia, D and Guo, S and Zheng, X and Yang, W and Chen, H and Zhang, Y and Yu, Q}, title = {Dual-action defense: A photothermal and controlled nitric oxide-releasing coating for preventing biofilm formation.}, journal = {Journal of colloid and interface science}, volume = {679}, number = {Pt B}, pages = {191-200}, doi = {10.1016/j.jcis.2024.10.109}, pmid = {39447462}, issn = {1095-7103}, mesh = {*Biofilms/drug effects ; *Nitric Oxide/chemistry/pharmacology/metabolism ; *Pseudomonas aeruginosa/drug effects/physiology ; *Staphylococcus aureus/drug effects/physiology ; *Anti-Bacterial Agents/pharmacology/chemistry ; Infrared Rays ; S-Nitrosothiols/chemistry/pharmacology ; Microbial Sensitivity Tests ; Surface Properties ; Coated Materials, Biocompatible/chemistry/pharmacology ; Particle Size ; Humans ; Photothermal Therapy ; }, abstract = {Biofilms formed by pathogenic bacteria on biomedical devices and implants pose a considerable challenge due to their resistance to conventional treatments and their role in severe infections. Preventing biofilm formation is strategically more advantageous than attempting to eliminate the mature biofilms, particularly in addressing the persistence of such formations. In this context, a dual-action antibiofilm coating is developed, utilizing S-nitrosothiols functionalized candle soot (CS), which capitalizes on CS's strong light absorption for photothermal therapy and the controlled release of nitric oxide (NO) from S-nitrosothiols to inhibit biofilm formation. This coating exhibits stable and efficient light-to-heat conversion, along with the ability to release NO gradually at physiological temperatures and to rapidly release NO on demand when triggered by a near-infrared (NIR) laser. Under NIR irradition, the coating generates heat swiftly and releases substantial amounts of NO, which synergistically disrupts bacterial membranes, leading to the leakage of intracellular components and the effective eradication of surface-adhered bacteria. In the absence of NIR irradiation, the coating continuously releases low concentrations of NO, which depletes exopolysaccharides and impedes biofilm formation. The antibiofilm efficacy of this coating is assessed against Staphylococcus aureus and Pseudomonas aeruginosa, demonstrating marked reductions in bacterial viability and biofilm formation in vitro. Additionally, the coating exhibits minimal cytotoxicity and can be easily applied to diverse substrates. This study underscores the potential of this coating as a broad-spectrum, non-toxic approach for preventing biofilm-related complications in biomedical applications.}, }
@article {pmid39446210, year = {2024}, author = {Li, Q and Takahashi, M and Enobi, K and Shimizu, K and Shinozaki, K and Wakahara, S and Sumino, T}, title = {Comammox Nitrospira was the dominant ammonia oxidizer in an acidic biofilm reactor at pH 5.5 and pH 5.}, journal = {Applied microbiology and biotechnology}, volume = {108}, number = {1}, pages = {494}, pmid = {39446210}, issn = {1432-0614}, support = {Academic Year of 2021//KUBOTA Corporation/ ; }, mesh = {*Biofilms/growth &amp; development ; Hydrogen-Ion Concentration ; *Ammonia/metabolism ; *Bioreactors/microbiology ; *Oxidation-Reduction ; *RNA, Ribosomal, 16S/genetics ; *Nitrification ; *Phylogeny ; *Bacteria/metabolism/genetics/classification ; High-Throughput Nucleotide Sequencing ; }, abstract = {Nitrification is a vital process in the biological removal of inorganic nitrogen compounds. In order to ensure the stability and effectiveness of this process, buffer solutions should be added to the system to maintain neutral to slightly alkaline conditions. With a focus on the newly discovered comammox Nitrospira, this research investigates the transition of the nitrifying community within a biofilm reactor under different acidic levels (initiated at pH 6 and gradually decreased to pH 5). During the 305-day continuous operation experiment, it was observed that responsible ammonia oxidizers transitioned from ammonia-oxidizing bacteria (AOB) during the initial stages (setup stage and early stage of pH 6) to comammox Nitrospira under pH 5.5 and pH 5. Further analysis using next-generation sequencing targeting both the 16S rRNA region and amoA region revealed a shift in the dominant cluster of both Nitrospirae and comammox Nitrospira under varying pH conditions. Our study identified a distinct cluster of comammox Nitrospira that is phylogenetically closed to sequences found in acidic environments, but exhibits dissimilarity from known comammox Nitrospira isolates and the majority of environmental sequences. This cluster was found to be prevalent in the acidic biofilm reactor studied and thrived particularly well at pH 5. These findings underscore the potential significance of this distinct, uncultivated group of comammox Nitrospira in performing ammonia oxidation under acidic conditions. KEY POINTS: • Ammonia was effectively removed under pH 5.5 and 5 in the biofilm reactor • The dominant ammonia oxidizer was comammox Nitrospira when pH was 5.5 and 5 • A potential acidophilic cluster of comammox Nitrospira was identified in this acidic biofilm reactor.}, }
@article {pmid39445815, year = {2024}, author = {Gupta, A and Guptasarma, P}, title = {E. coli cells advance into phase-separated (biofilm-simulating) extracellular polymeric substance containing DNA, HU, and lipopolysaccharide.}, journal = {Journal of bacteriology}, volume = {206}, number = {11}, pages = {e0030924}, pmid = {39445815}, issn = {1098-5530}, support = {MHRD-14-0064//Ministry of Education Government of India/ ; //Tata Transformation Prize (Tata Sons and the New York Academy of Sciences)/ ; }, mesh = {*Lipopolysaccharides/metabolism ; *Escherichia coli/metabolism/genetics ; *Biofilms/growth &amp; development ; *Escherichia coli Proteins/metabolism/genetics ; *DNA, Bacterial/genetics/metabolism ; *DNA-Binding Proteins/metabolism/genetics ; Bacterial Adhesion ; Extracellular Polymeric Substance Matrix/metabolism/chemistry ; }, abstract = {UNLABELLED: We have previously shown that the nucleoid-associated protein, HU, uses its DNA-binding surfaces to bind to bacterial outer-membrane lipopolysaccharide (LPS), causing HU to act as a glue aiding the adherence of DNA to bacteria, e.g., in biofilms. We have also previously shown that HU and DNA coacervate into a state of liquid-liquid phase separation (LLPS), within bacterial cells and also in vitro. Here, we show that HU and free LPS (which is ordinarily shed by bacteria) also condense into a state of phase separation. Coacervates of HU, DNA, and free LPS are less liquid-like than coacervates of HU and DNA. Escherichia coli cells bearing LPS on their surfaces are shown to adhere to (as well as advance into) coacervates of HU and DNA. HU appears to play a role, therefore, in maintaining both intracellular and extracellular states of phase separation with DNA that are compatible with LPS and LPS-bearing E. coli, with LPS determining the liquidity of the biofilm-simulating coacervate.<br><br>IMPORTANCE: Understanding the constitution and behavior of biofilms is crucial to understanding how to deal with persistent biofilms. This study, together with other recent studies from our group, elucidates a novel aspect of the extracellular polymeric substance (EPS) of Escherichia coli biofilms, by creating a simulacrum of the EPS and then demonstrating that its formation involves liquid-liquid phase separation (LLPS) of HU, DNA, and lipopolysaccharide (LPS) components, with LPS determining the liquidity of this EPS simulacrum. The findings provide insight into the nature of biofilms and into how the interplay of HU, DNA, and LPS could modulate the structural integrity and functional dynamics of biofilms.}, }
@article {pmid39444053, year = {2025}, author = {Bai, Y and Guo, HL and Hua, T and Li, B and Feng, G and Zhang, Z and Teng, Y and Liu, Y and Qian, N and Zheng, B}, title = {Time-Responsive Activity of Engineered Bacteria for Local Sterilization and Biofilm Removal in Periodontitis.}, journal = {Advanced healthcare materials}, volume = {14}, number = {1}, pages = {e2401190}, doi = {10.1002/adhm.202401190}, pmid = {39444053}, issn = {2192-2659}, support = {2021YFC2600503//National Key Research and Development Program of China/ ; 32271400//National Natural Science Foundation of China/ ; 21JCZDJC00690//Key Project of Tianjin Natural Science Foundation/ ; }, mesh = {*Periodontitis/microbiology/therapy ; *Biofilms/drug effects ; Animals ; *Porphyromonas gingivalis/drug effects ; Rats ; *Escherichia coli/drug effects ; Probiotics/pharmacology ; Rats, Sprague-Dawley ; Sterilization/methods ; Male ; Antimicrobial Peptides/chemistry/pharmacology ; Disease Models, Animal ; }, abstract = {Periodontitis is a highly prevalent and common condition in people of all ages, however, existing drugs to treat periodontitis have difficulty penetrating complex biofilms. Here, we report a biofilm-penetrating probiotic hybrid strategy for the treatment of periodontitis. It consists of therapeutic probiotics of E. coli Nissle 1917, which can produce antimicrobial peptides and hydrogen, and is coated with D-amino acids that can penetrate biofilms. After the fusion of D-amino acids with the biofilm, EcN entered the plaque biofilm and produced antimicrobial peptides to kill porphyromonas gingivalis and eliminate periodontitis under the action of hydrogen. The efficacy of EcN@DA-D in biofilm penetration and treatment of periodontitis was demonstrated in a rat model of periodontitis. In addition, the clinical combination to construct a rat periodontitis model by using clinical tissue has a significant therapeutic effect. In conclusion, EcN@DA-D offers a promising topical treatment for periodontitis without developing detectable pathogen resistance and side effects.}, }
@article {pmid39442395, year = {2024}, author = {Moulia, V and Heran, M and Lesage, G and Hamelin, J and Pinta, J and Gazon, A and Penlae, M and Bru-Adan, V and Wéry, N and Ait-Mouheb, N}, title = {Biofilm growth dynamics in a micro-irrigation with reclaimed wastewater in the field scale.}, journal = {Journal of environmental management}, volume = {370}, number = {}, pages = {122976}, doi = {10.1016/j.jenvman.2024.122976}, pmid = {39442395}, issn = {1095-8630}, mesh = {*Biofilms ; *Wastewater ; Biofouling ; Agricultural Irrigation ; Waste Disposal, Fluid/methods ; }, abstract = {The dripper clogging due to the development of biofilm can reduce the benefits of micro-irrigation technology implementation using reclaimed wastewater. The narrow cross-section and labyrinth geometry of the dripper channel enhance the fouling mechanisms. The aim of this study was to evaluate the water distribution and biofouling of drip irrigation systems at the field scale during irrigation with treated wastewater. Six 100 m lines of commercial pipes with two pressure-compensating dripper types (flow rate, Q, of 0.65 L h[-1] and 1.5 L h[-1], respectively) were monitored for four months. Different zones along the pipes were selected to evaluate the influence of hydrodynamical conditions (Reynolds number = 5400 to 0) on biofouling. Destructive methods involving the biofilm extraction by mechanical means, showed little biofilm development without significant differences in dry and organic matter content in function of the sampling location along the pipe or dripper flow rate (Q0.65 and Q1.5). These results were confirmed by non-destructive methods, such as optical coherence tomography, that nevertheless showed that biofouling concerned 15-20% of the total dripper labyrinth volume. Total organic carbon monitoring and its composition (by three-dimensional excitation and emission matrix fluorescence microscopy) showed that the biofilm did not significantly influence the organic matter nature. Our results indicated that the biological activity and biofilm development in irrigation systems were more affected by the environmental conditions, particularly water temperature, rather than flow conditions. This confirmed that treated wastewater with low organic content can be used in micro-irrigation systems without significant loss of efficiency, even in conditions requiring intensive irrigation, such as the Mediterranean climate.}, }
@article {pmid39441613, year = {2024}, author = {Yang, H and Yang, K}, title = {The Biofilm Removal and Bactericidal Effect of an 810-nm High-Power Laser on an Orthodontic Bracket Surface: An In Vitro Study.}, journal = {Photobiomodulation, photomedicine, and laser surgery}, volume = {42}, number = {12}, pages = {779-788}, doi = {10.1089/photob.2024.0088}, pmid = {39441613}, issn = {2578-5478}, mesh = {*Biofilms/radiation effects ; *Streptococcus mutans/radiation effects ; *Orthodontic Brackets/microbiology ; Humans ; In Vitro Techniques ; Dental Scaling/instrumentation ; Surface Properties ; Low-Level Light Therapy ; }, abstract = {Objective: The present study aimed to analyze the biofilm removal and bactericidal effect of laser treatment alone and laser combined with ultrasonic scaling on orthodontic brackets. It also assessed whether the use of a laser can improve the efficiency of biofilm removal and bactericidal effect compared with traditional ultrasonic instrumentation. Background Data: Streptococcus mutans (S. mutans) can lead to white spots and dental caries. Orthodontic brackets make teeth cleaning more difficult, and biofilms or bacteria on the surface of brackets worsen the oral environment, which may cause some oral diseases. Laser can be used for biofilm removal and killing bacteria on the surface of an object through thermal, photochemical, and pressure effects, which is widely used in the treatment of oral diseases. Methods: A total of 600 mandibular incisor brackets were collected for this study. Among these, 320 unused brackets were used for the S. mutans crystal violet assay (n = 160) and for S. mutans live/dead bacterial staining (n = 160). Another 280 brackets, obtained from patients who had undergone therapy for over two years, were used for the mature multispecies biofilms removal assay (n = 120) and multispecies bacterial live/dead bacterial staining (n = 160). Ultrasonic scaling, laser, and laser combined with ultrasonic scaling were applied to the labial surface of brackets covered by S. mutans biofilm or mature multispecies biofilms. Specifically, we used the following three methods: ultrasonic scaling for 10 sec without laser; 810-nm laser (Doctor Smile, Italy, LA5D0 001.1) with 0.3-mm spot size at total 21.2 kJ/cm[2] for 10 sec; and 810-nm laser at total 10.6 kJ/cm[2] for 5 sec, followed by ultrasonic scaling for 5 sec. The 810-nm diode laser removed biofilms with a power of 1.5 W and a power density of 2.12 kW/cm[2]. The S. mutans biofilm was examined using crystal violet assay, and scanning electron microscopy (SEM) was used for mature multispecies biofilms to evaluate the effect of the three methods on biofilm removal. Live/dead bacterial staining was used to examine the bactericidal effect on remaining biofilms by confocal laser scanning microscopy (CLSM). Results: For S. mutans biofilm, the optical density (OD) value and live/dead bacterial ratio in the laser and the laser combined with ultrasonic scaling groups were significantly lower than those in the ultrasonic scaling group (p < 0.05); moreover, the OD value and the live/dead bacterial ratio in laser treatment combined with ultrasonic scaling and laser treatment alone showed no significant difference (p > 0.05). For mature multispecies biofilms, the percentage of biofilm coverage after treatment was higher in the laser group than in the ultrasonic scaling group (p < 0.05) and lower in the laser combined with ultrasonic scaling group than in the ultrasonic scaling group (p < 0.05), and live/dead bacterial staining showed that laser treatment alone killed the most bacteria, followed by laser treatment combined with ultrasonic scaling, while ultrasonic scaling alone seldom killed bacteria. Conclusions: Laser treatment alone has a better bactericidal effect and can also remove more S. mutans biofilm than ultrasonic scaling alone, but it fails to remove more mature multispecies biofilms. Laser treatment combined with ultrasonic scaling can remove more S. mutans biofilm and mature multispecies biofilms than ultrasonic scaling alone and also has a better bactericidal effect than ultrasonic scaling alone on a bracket surface.}, }
@article {pmid39441196, year = {2024}, author = {Liu, JJ and Liu, J and Huang, YS and Chen, WM and Lin, J}, title = {Cyclic Diguanylate G-Quadruplex Inducer-Quorum Sensing Inhibitor Hybrids as Bifunctional Anti-biofilm and Anti-virulence Agents Against Pseudomonas aeruginosa.}, journal = {Journal of medicinal chemistry}, volume = {67}, number = {21}, pages = {18911-18929}, doi = {10.1021/acs.jmedchem.4c01253}, pmid = {39441196}, issn = {1520-4804}, mesh = {*Pseudomonas aeruginosa/drug effects ; *Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; *Quorum Sensing/drug effects ; *Cyclic GMP/analogs &amp; derivatives/metabolism ; *Caenorhabditis elegans/microbiology ; *G-Quadruplexes/drug effects ; Animals ; Virulence/drug effects ; Microbial Sensitivity Tests ; Pseudomonas Infections/drug therapy/microbiology ; }, abstract = {The release of virulence factors and biofilm formation by Pseudomonas aeruginosa are pivotal drivers of its severe pathogenicity and antibiotic resistance. Based on our prior findings, cyclic di-GMP (c-di-GMP) G-quadruplex inducers are promising biofilm inhibitors and that quorum sensing systems are central regulators of virulence, we aimed to design and synthesize c-di-GMP G-quadruplex inducer-quorum sensing inhibitor hybrids. These hybrids were envisioned as bifunctional agents with both antibiofilm and antivirulence capabilities. Hybrids A7 and A11, characterized by their quinoline and 3-indole rings, emerged as potent inhibitors. They achieve this dual action by inducing c-di-GMP G-quadruplex formation and disrupting the las and pqs signaling system. Additionally, hybrids A7 and A11 attenuated virulence factors and inhibited the motility phenotypes of P. aeruginosa. Furthermore, when tested in in vivo Caenorhabditis elegans infection models, these hybrids, in combination with antibiotics such as tetracycline, improved survival rates, all while maintaining a favorable biosafety profile.}, }
@article {pmid39440543, year = {2024}, author = {Ma, Z and Ai, D and Ge, Z and Wu, T and Zhang, J}, title = {Chlormequat inhibits Vallisneria natans growth and shapes the epiphytic biofilm microbial community.}, journal = {Water environment research : a research publication of the Water Environment Federation}, volume = {96}, number = {10}, pages = {e11148}, doi = {10.1002/wer.11148}, pmid = {39440543}, issn = {1554-7531}, support = {42377053//National Natural Science Foundation of China/ ; SS202110//Suzhou Science and Technology Plan Project/ ; 22ZR1446500//Natural Science Foundation of Shanghai/ ; }, mesh = {*Biofilms/drug effects ; Microbiota/drug effects ; Hydrocharitaceae ; Plant Leaves ; Chlorophyll ; Bacteria/drug effects/classification ; }, abstract = {Submerged macrophytes can overgrow and negatively affect freshwater ecosystems. This study aimed to investigate the use of chlormequat (CQ) to regulate submerged Vallisneria natans growth as well as its impact on the microbial community of epiphytic biofilms. V. natans height under CQ dosages of 20, 100, and 200 mg/L decreased within 21 days by 12.57%, 30.07%, and 44.62%, respectively, while chlorophyll content increased by 1.94%, 20.39%, and 38.83%. At 100 mg/L, CQ reduced the diversity of bacteria in the biofilm attached to V. natans leaves but increased the diversity of the eukaryotic microbial community. CQ strongly inhibited Cyanobacteria; compared with the control group, the treatment group experienced a significant reduction from 36.54% to 2.61%. Treatment significantly inhibited Gastrotricha and Rotifera, two dominant phyla of eukaryotes in the leaf biofilm, reducing their relative abundances by 17.41% and 6.48%, respectively. CQ significantly changed the leaf biofilm microbial community correlation network. The treatment group exhibited lower modularity (2.012) compared with the control group (2.249); however, the central network of the treated group contained a higher number of microbial genera (13) than the control group (4), highlighting the significance of eukaryotic genera in the network. The results obtained from this study provide invaluable scientific context and technical understanding pertinent to the restoration of submerged macrophytes within aquatic ecosystems. PRACTITIONER POINTS: Chlormequat reduced the plant height but increased leaf chlorophyll content. Chlormequat reduced biofilm bacterial diversity but increased eukaryotic diversity. Chlormequat affected the bacterial-fungal association networks in biofilms.}, }
@article {pmid39439203, year = {2024}, author = {Sajid, S and Zhang, G and Zhang, Z and Chen, L and Lu, Y and Fang, JK and Cai, L}, title = {Comparative analysis of biofilm bacterial communities developed on different artificial reef materials.}, journal = {Journal of applied microbiology}, volume = {135}, number = {11}, pages = {}, doi = {10.1093/jambio/lxae268}, pmid = {39439203}, issn = {1365-2672}, support = {2019YFE0198500//National Key Research and Development Program of China/ ; MHP/009/19//Innovation and Technology Fund/ ; }, mesh = {*Biofilms/growth &amp; development ; *Coral Reefs ; Animals ; *Bacteria/genetics/classification/isolation &amp; purification ; *Anthozoa/microbiology ; *Seawater/microbiology ; *RNA, Ribosomal, 16S/genetics ; Larva/microbiology ; Microbiota ; }, abstract = {AIMS: Artificial reefs play a vital role in restoring and creating new habitats for marine species by providing suitable substrates, especially in areas where natural substrates have been degraded or lost due to declining water quality, destructive fishing practices, and coral diseases. Artificial reef restoration aimed at coral larval settlement is gaining prominence and initially depends on the development of biofilms on reef surfaces. In this study, we hypothesized that different artificial reef materials selectively influence the composition of biofilm bacterial communities, which in turn affected coral larval settlement and the overall success of coral rehabilitation efforts. To test this hypothesis, we evaluated the impact of six different reef-made materials (porcelain, granite, coral skeleton, calcium carbonate, shell cement, and cement) on the development of biofilm bacterial communities and their potential to support coral larval settlement.<br><br>METHODS AND RESULTS: The biofilm bacterial communities were developed on different artificial reef materials and studied using 16S rRNA gene amplicon sequencing and analysis. The bacterial species richness and evenness were significantly (P&#xa0;<&#xa0;0.05) low in the seawater, while these values were high in the reef materials. At the phylum level, the biofilm bacterial composition of all materials and seawater was majorly composed of Pseudomonadota, Cyanobacteria, and Bacteroidetes; however, significantly (P&#xa0;<&#xa0;0.05) low Bacteroidetes were found in the seawater. At the genus level, Thalassomonas, Glaciecola, Halomicronema, Lewinella, Hyphomonas, Thalassospira, Polaribacter, and Tenacibaculum were significantly (P&#xa0;<&#xa0;0.05) low in the coral skeleton and seawater, compared to the other reef materials. The genera Pseudoaltermonas and Thalassomonas (considered potential inducers of coral larval settlement) were highly abundant in the shell-cement biofilm, while low values were found in the biofilm of the other materials.<br><br>CONCLUSION: The biofilm bacterial community composition can be selective for different substrate materials, such as shell cement exhibited higher abundances of bacteria known to facilitate coral larval settlement, highlighting their potential in enhancing restoration outcomes.}, }
@article {pmid39438820, year = {2024}, author = {Ajose, DJ and Abolarinwa, TO and Oluwarinde, BO and Montso, PK and Fayemi, OE and Aremu, AO and Ateba, CN}, title = {Whole genome sequence analysis of multi-drug resistant and biofilm-forming Staphylococcus haemolyticus isolated from bovine milk.}, journal = {BMC microbiology}, volume = {24}, number = {1}, pages = {426}, pmid = {39438820}, issn = {1471-2180}, mesh = {Animals ; Cattle ; *Milk/microbiology ; *Staphylococcus haemolyticus/genetics/drug effects/isolation &amp; purification ; *Drug Resistance, Multiple, Bacterial/genetics ; *Whole Genome Sequencing ; *Biofilms/growth &amp; development/drug effects ; Female ; *Mastitis, Bovine/microbiology ; *Staphylococcal Infections/microbiology/veterinary ; *Anti-Bacterial Agents/pharmacology ; *Genome, Bacterial/genetics ; Base Composition ; Microbial Sensitivity Tests ; }, abstract = {BACKGROUND: Milk is an excellent growth medium for microorganisms due to its nutritive composition. Microorganisms have been implicated in bovine mastitis (BM) in dairy cows as well as causing infections in animals and humans. Despite extensive endeavours to manage BM, this condition continues to persist as the most prevalent and economically burdensome problem affecting dairy cattle on a global scale. Non-aureus staphylococci (NAS) species such as Staphylococcus haemolyticus, S. epidermidis, and S. xylosus are currently the predominant microbiological agents identified as the main cause of subclinical udder infections and are also considered opportunistic pathogens in cases of clinical mastitis in dairy cows. Therefore, it is crucial to elucidate the genetic profile of these species. The primary objective of this study was to characterise three phenotypically determined multidrug-resistant NAS environmental strains (NWU MKU1, NWU MKU2, and NWU MKS3) obtained from dairy cows milk via whole-genome sequencing.<br><br>RESULTS: The results confirmed that the three isolates were S. haemolyticus with genome sizes of 2.44, 2.56, and 2.56&#xa0;Mb and a G&#x2009;+&#x2009;C content of 32.8%. The genomes contained an array of antibiotic resistance genes that may potentially confer resistance to a range of antibiotic classes, such as macrolides, fluoroquinolones, aminoglycosides, cephalosporins, tetracyclines, peptides, and phenicol. Furthermore, all the genomes carried virulence genes, which are responsible for several functions, such as adhesion, enzyme and toxin production. The genomes of these organisms contained signatures encoding mobile genetic elements such as prophages and insertion sequences.<br><br>CONCLUSION: These findings indicate there is a need for diligent monitoring with improved management practices and quality control strategies on farms to safeguard milk production systems and human health.}, }
@article {pmid39438809, year = {2024}, author = {Elawady, R and Aboulela, AG and Gaballah, A and Ghazal, AA and Amer, AN}, title = {Correction: Antimicrobial Sub-MIC induces Staphylococcus aureus biofilm formation without affecting the bacterial count.}, journal = {BMC infectious diseases}, volume = {24}, number = {1}, pages = {1194}, pmid = {39438809}, issn = {1471-2334}, }
@article {pmid39437681, year = {2025}, author = {Kim, S and Mah, JH}, title = {Variation in heat resistance and biofilm formation of Bacillus cereus spores in various fermented soybean foods.}, journal = {International journal of food microbiology}, volume = {427}, number = {}, pages = {110939}, doi = {10.1016/j.ijfoodmicro.2024.110939}, pmid = {39437681}, issn = {1879-3460}, mesh = {*Bacillus cereus/physiology ; *Biofilms/growth &amp; development ; *Spores, Bacterial/physiology ; *Hot Temperature ; *Soy Foods/microbiology ; *Glycine max/microbiology ; *Food Microbiology ; Fermented Foods/microbiology ; Hydrogen-Ion Concentration ; Fermentation ; Republic of Korea ; }, abstract = {This study investigated the heat resistance of Bacillus cereus spores (as well as spores in intact biofilm) in two types of Korean fermented soybean foods and presumed the potential key parameters (physicochemical and nutritional properties) associated with their heat resistance. For example, the D100°C-values of B. cereus ATCC 10987 and CH3 spores with strong heat resistance and prolific biofilm-forming capability were compared in various Jjigae-type (Cheonggukjang jjigae, Doenjang jjigae, and Gochujang jjigae) and Jang-type (Cheonggukjang, Doenjang, and Gochujang) foods commonly consumed in Korea. The D100°C-values of planktonic spores were significantly different depending on the type of food, that is, Jang and Jjigae. Compared with Jjigae-type foods, a higher heat resistance of B. cereus spores was found in Jang-type foods (particularly Doenjang and Gochujang) with low water activity and high salinity. In Jjigae-type foods, spore heat resistance showed a positive correlation with the pH of Jjigaes, indicating that an acidic environment weakens the spores. A negative correlation between the total fat content and spore heat resistance was found in Jjigae-type foods but not in Jang-type foods. Meanwhile, regarding the heat resistance of B. cereus spores in intact biofilm, the D100°C-values were significantly higher (up to 6.5-fold) than those of planktonic spores in all Jjigae-type foods. The slightly acidic pH and amount of carbohydrates are likely related to the large formation of extracellular polymeric substances and strong heat resistance of B. cereus spores in biofilm. This study may provide a comprehensive understanding of the relationship between the key parameters of foods and heat resistance of B. cereus spores with or without intact biofilm and methods to control their risks in different types of fermented soybean foods.}, }
@article {pmid39436423, year = {2024}, author = {Hirota, A and Kouduka, M and Fukuda, A and Miyakawa, K and Sakuma, K and Ozaki, Y and Ishii, E and Suzuki, Y}, title = {Biofilm Formation on Excavation Damaged Zone Fractures in Deep Neogene Sedimentary Rock.}, journal = {Microbial ecology}, volume = {87}, number = {1}, pages = {132}, pmid = {39436423}, issn = {1432-184X}, mesh = {*Biofilms/growth &amp; development ; *RNA, Ribosomal, 16S/genetics ; *Geologic Sediments/microbiology ; Phylogeny ; Groundwater/microbiology ; Bacteria/genetics/classification/isolation &amp; purification/metabolism ; Gammaproteobacteria/genetics/isolation &amp; purification ; DNA, Bacterial/genetics ; }, abstract = {Deep underground galleries are used to access the deep biosphere in addition to mining and other engineering applications, such as geological disposal of radioactive waste. Fracture networks developed in the excavation damaged zone (EDZ) are concerned with accelerating mass transport, where microbial colonization might be possible due to the availability of space and nutrients. In this study, microbial biofilms at EDZ fractures were investigated by drilling from a 350-m-deep gallery and subsequent borehole logging at the Horonobe Underground Research Laboratory (URL). By using microscopic and spectroscopic techniques, the dense colonization of microbial cells was demonstrated at the surfaces of the EDZ fractures with high hydraulic conductivity. 16S rRNA gene sequence analysis revealed the dominance of gammaproteobacterial lineages, the cultivated members of which are aerobic methanotrophs. The near-complete genomes from Horonobe groundwater, affiliated with the methanotrophic lineages, were fully equipped with genes involved in aerobic methanotrophy. Although the mediation of aerobic methanotrophy remains to be demonstrated, microbial O2 production was supported by the presence of genes in the near-complete genomes, such as catalase and superoxide dismutase that produce O2 from reactive oxygen species and a nitric oxide reductase gene with the substitutions of amino acids in motifs. It is concluded that the EDZ fractures provide energetically favorable subsurface habitats for microorganisms.}, }
@article {pmid39436243, year = {2024}, author = {Seredin, PV and Ippolitov, YA and Peshkov, YA and Goloshchapov, DL and Ippolitov, IY and Avraamova, OG}, title = {[Distinctions in molecular composition of the dental biofilm in a dependence of method of exo/endogeneous caries prevention and cariogenic condition of a patient].}, journal = {Stomatologiia}, volume = {103}, number = {5}, pages = {5-12}, doi = {10.17116/stomat20241030515}, pmid = {39436243}, issn = {0039-1735}, mesh = {Humans ; *Biofilms ; *Dental Caries/microbiology/prevention &amp; control ; Dental Enamel/microbiology ; Adult ; Male ; Glycerophosphates ; Female ; Protein Structure, Secondary ; Spectrophotometry, Infrared ; }, abstract = {OBJECTIVE: Comparative study of changes in the secondary structure of dental biofilm proteins in people with cariesogenic and cariesoprotective status using synchrotron IR microspectroscopy.<br><br>MATERIALS AND METHODS: Dental biofilm samples from 50 patients without caries (group 1) and with carious lesions of tooth enamel (group 2) were studied. The molecular composition of biofilms was studied using IR microspectroscopy. Changes in the secondary structure of dental biofilm proteins were evaluated based on deconvolution of Amide I or Amide II amide bands. using the analysis of variance. Patients of both groups took tablets containing a mineral complex with calcium glycerophosphate.<br><br>RESULTS: Based on the deconvolution of the IR spectral profile of the Amide I and Amide II bands, the changes occurring in the secondary structure of dental biofilm proteins have been studied. Using a large set of spectra, it was shown that the prediction of the secondary structure of the biofilm protein network is influenced by both the cariesogenic situation in the oral cavity (with initial carious lesions of the enamel) and the fact that patients use a modulator - calcium glycerophosphate (a tableted mineral complex with calcium glycerophosphate). Significant intra-group and intergroup differences in the secondary structure of dental biofilm proteins were established for patients in normal and carisogenic situations in the mouth, including after the use of a tableted mineral complex with calcium glycerophosphate. This allowed us to give a mathematical assessment of shifts in the secondary structure of proteins depending on the activity of caries and external modulation.<br><br>CONCLUSION: The results obtained can form the basis of a technique for spectroscopic diagnosis of changes (shifts) in the oral microbiome leading to the development of the carious process, as well as become the basis for choosing the optimal therapeutic ways to treat enamel caries, including through preventive measures aimed at restoring the microflora of the patient's oral cavity.}, }
@article {pmid39436122, year = {2024}, author = {Kang, HJ and You, J-Y and Kim, SH and Moon, J-S and Kim, H-Y and Kim, J-M and Lee, YJ and Kang, H-M}, title = {Characteristics of methicillin-resistant Staphylococcus aureus isolates from bovine mastitis milk in South Korea: molecular characteristics, biofilm, virulence, and antimicrobial resistance.}, journal = {Microbiology spectrum}, volume = {12}, number = {12}, pages = {e0119724}, pmid = {39436122}, issn = {2165-0497}, abstract = {UNLABELLED: Methicillin-resistant Staphylococcus aureus (MRSA) is a drug-resistant pathogen causing subclinical and clinical bovine mastitis. This study examined the molecular properties, biofilm formation, virulence genes, and antimicrobial susceptibility of MRSA isolates from mastitis-infected dairy cow milk in South Korea. Whole-genome sequencing of an ST22-SCCmec IV MRSA strain positive for Panton-Valentine leukocidin (PVL) and toxic shock syndrome toxin-1 (TSST-1) was also performed. Of the 488 S. aureus isolates, 30 (6.1%) were identified as MRSA, harboring the mecA gene. MRSA exhibited the highest resistance to kanamycin (66.7%) among non-beta-lactam antibiotics. Multidrug resistance was observed in 83.3% of MRSA isolates. All MRSA strains had the capacity to form biofilm and harbored biofilm-related genes. The primary virulence genes included hla, hlb, lukED, seg, sei, sem, sen, and seo. The ST72-t324-SCCmec IV genotype was the most prevalent. Of note, three ST22-SCCmec IV isolates were positive for PVL and TSST-1. Our findings suggest that the majority of MRSA isolates from milk obtained from dairy cows with mastitis are multidrug-resistant, capable of forming robust biofilms, and harbor multiple virulence genes. The presence of PVL- and TSST-1-positive ST22-SCCmec IV isolates in mastitis-infected bovine milk highlights the need for persistent monitoring to mitigate possible public health risks.<br><br>IMPORTANCE: This study reports on the presence and characteristics of methicillin-resistant Staphylococcus aureus strains in milk from mastitis-infected cows. To our knowledge, this is the first report of a Panton-Valentine leukocidin- and toxic shock syndrome toxin-1-positive ST22-SCCmec IV strain in South Korea.}, }
@article {pmid39436054, year = {2024}, author = {Finn, JP and Luzinski, C and Burton, BM}, title = {Differential expression of the yfj operon in a Bacillus subtilis biofilm.}, journal = {Applied and environmental microbiology}, volume = {90}, number = {11}, pages = {e0136224}, pmid = {39436054}, issn = {1098-5336}, support = {WIS02030//U.S. Department of Agriculture (USDA)/ ; //Wisconsin Alumni Research Foundation (WARF)/ ; //Wisconsin Alumni Research Foundation (WARF)/ ; }, mesh = {*Bacillus subtilis/genetics/metabolism/physiology ; *Biofilms/growth &amp; development ; *Operon ; *Gene Expression Regulation, Bacterial ; *Bacterial Proteins/genetics/metabolism ; Type VII Secretion Systems/genetics/metabolism ; Promoter Regions, Genetic ; }, abstract = {Type VII protein secretion systems play an important role in the survival and virulence of pathogens and in the competition among some microbes. Potential polymorphic toxin substrates of the type VII secretion system (T7SS) in Bacillus subtilis are important for competition in the context of biofilm communities. Within a biofilm, there is significant physiological heterogeneity as cells within the population take on differential cell fates. Which cells express and deploy the various T7SS substrates is still unknown. To identify which cells express at least one of the T7SS substrates, we investigated the yfj operon. The yfjABCDEF operon encodes at least one predicted T7SS substrate. Starting with an in silico analysis of the yfj operon promoter region, we identified potential regulatory sequences. Using a yfj promoter-reporter fusion, we then identified several regulators that impact expression of the operon, including a regulator of biofilm formation, DegU. In a degU deletion mutant, yfj expression is completely abolished. Mutation of predicted DegU binding sites also results in a significant reduction in yfj reporter levels. Further analysis of yfj regulation reveals that deletion of spo0A has the opposite effect of the degU deletion. Following the yfj reporter by microscopy of cells harvested from biofilms, we find that the yfj operon is expressed specifically in the subset of cells undergoing sporulation. Together, our results define cells entering sporulation as the subpopulation most likely to express products of the yfj operon in B. subtilis.IMPORTANCEDifferential expression of genes in a bacterial community allows for the division of labor among cells in the community. The toxin substrates of the type VII secretions system (T7SS) are known to be active in Bacillus subtilis biofilm communities. This work describes the expression of one of the T7SS-associated operons, the yfj operon, which encodes the YFJ toxin, in the sporulating subpopulation within a biofilm. The evidence that the YFJ toxin may be deployed specifically in cells at the early stages of sporulation provides a potential role for deployment of T7SS in community-associated activities, such as cannibalism.}, }
@article {pmid39435185, year = {2024}, author = {Mayorga-Ramos, A and Carrera-Pacheco, SE and Barba-Ostria, C and Guamán, LP}, title = {Bacteriophage-mediated approaches for biofilm control.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1428637}, pmid = {39435185}, issn = {2235-2988}, mesh = {*Biofilms/growth &amp; development ; *Bacteriophages/physiology/genetics ; *Phage Therapy/methods ; Humans ; Anti-Bacterial Agents/pharmacology ; Bacteria/virology/genetics ; }, abstract = {Biofilms are complex microbial communities in which planktonic and dormant bacteria are enveloped in extracellular polymeric substances (EPS) such as exopolysaccharides, proteins, lipids, and DNA. These multicellular structures present resistance to conventional antimicrobial treatments, including antibiotics. The formation of biofilms raises considerable concern in healthcare settings, biofilms can exacerbate infections in patients and compromise the integrity of medical devices employed during treatment. Similarly, certain bacterial species contribute to bulking, foaming, and biofilm development in water environments such as wastewater treatment plants, water reservoirs, and aquaculture facilities. Additionally, food production facilities provide ideal conditions for establishing bacterial biofilms, which can serve as reservoirs for foodborne pathogens. Efforts to combat antibiotic resistance involve exploring various strategies, including bacteriophage therapy. Research has been conducted on the effects of phages and their individual proteins to assess their potential for biofilm removal. However, challenges persist, prompting the examination of refined approaches such as drug-phage combination therapies, phage cocktails, and genetically modified phages for clinical applications. This review aims to highlight the progress regarding bacteriophage-based approaches for biofilm eradication in different settings.}, }
@article {pmid39434616, year = {2025}, author = {Sahu, P and Chakraborty, S and Isab, AA and Mandal, SM and Dinda, J}, title = {Biofilm Demolition by [Au[III](N N)Cl(NHC)][PF6]2 Complexes Fastened with Bipyridine and Phenanthroline Ligands; Potent Antibacterial Agents Targeting Membrane Lipid.}, journal = {ChemPlusChem}, volume = {90}, number = {1}, pages = {e202400543}, doi = {10.1002/cplu.202400543}, pmid = {39434616}, issn = {2192-6506}, support = {Biju Patnaik Research Fellowship Scheme//Science and Technology Department, Government of Odisha/ ; }, mesh = {*Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; *Phenanthrolines/chemistry/pharmacology ; *Microbial Sensitivity Tests ; *Biofilms/drug effects ; *Gold/chemistry/pharmacology ; Humans ; Ligands ; Coordination Complexes/chemistry/pharmacology/chemical synthesis ; 2,2'-Dipyridyl/chemistry/pharmacology ; Pseudomonas aeruginosa/drug effects ; Staphylococcus aureus/drug effects ; }, abstract = {The development of new antibacterial drugs is essential for staying ahead of evolving antibiotic resistant bacterial (ARB) threats, ensuring effective treatment options for bacterial infections, and protecting public health. Herein, we successfully designed and synthesized two novel gold(III)- NHC complexes, [Au(1)(bpy)Cl][PF6]2 (2) and [Au(1)(phen)Cl][PF6]2 (3) based on the proligand pyridyl[1,2-a]{2-pyridylimidazol}-3-ylidene hexafluorophosphate (1⋅HPF6) [bpy=2,2'-bipyridine; phen=1,10-phenanthroline]. The synthesized complexes were characterized spectroscopically; their geometries and structural arrangements were confirmed by single crystal XRD analysis. Complexes 2 and 3 showed photoluminescence properties at room temperature and the time-resolved fluorescence decay confirmed the fluorescence lifetimes of 0.54 and 0.62 ns respectively; which were used to demonstrate their direct interaction with bacterial cells. Among the two complexes, complex 3 was found to be more potent against the bacterial strains (Staphylococcus aureus, Gram-positive and Pseudomonas aeruginosa, Gram-negative bacteria) with the MIC values of 8.91 μM and 17.82 μM respectively. Studies revealed the binding of the complexes with the fundamental phospholipids present in the cell membrane of bacteria, which was found to be the leading cause of bacterial cell death. Cytotoxicity was evaluated using an MTT assay on 293 T cell lines; emphasizing the potential therapeutic uses of the Au(III)-NHC complexes to control bacterial infections.}, }
@article {pmid39432995, year = {2025}, author = {Zhou, L and Wu, F and Ou, P and Li, H and Zhuang, WQ}, title = {Non-electroactive bacteria behave variously in AnMBR biofilm control using electric field.}, journal = {Water research}, volume = {268}, number = {Pt A}, pages = {122646}, doi = {10.1016/j.watres.2024.122646}, pmid = {39432995}, issn = {1879-2448}, mesh = {*Biofilms ; *Bioreactors/microbiology ; *Electricity ; Bacteria ; }, abstract = {Electroactive bacteria are often regarded as key players responding to electric fields that are used to control biofilm development during AnMBR (anaerobic membrane bioreactor) operation. Consequently, little attention has been given to non-electroactive bacteria in the same systems because of their incapability to acquire and transfer electrons directly. However, in this study, we identified some functionally important non-electroactive bacteria from biofilm established under low-voltage (0, 0.3, 0.5 and 1 V) electric fields in AnMBRs, designated as E-AnMBRs in this study. During the whole experiment, non-electroactive bacteria, mainly belonging to Proteobacteria, Bacteroidetes, and Chloroflexi, were found in all biofilm samples taken from each E-AnMBR. Under 0.3 V and 1 V conditions, non-electroactive bacteria did not seem to contribute to the development of biofilm significantly. Whereas under 0.5 V conditions, the growth of non-electroactive bacteria contributed up to 0.61 kPa/day biofilm formation. Therefore, 0.5 V was identified as a critical voltage, leading to the most severe biofilm formation. The microbial community structure in the reactor with a 0.5 V electric field was distinctly unique, caused by the increase of non-electroactive bacterial activity and the upregulation of their metabolic pathways. Notably, functional genes involved in carbon metabolism and oxidative phosphorylation pathway were upregulated. Furthermore, the 0.5 V electric field enhanced the protein/polysaccharide ratio and increased zeta potential to 31.6 mV (p < 0.01) of the biofilm samples. This was because upregulating quorum sensing genes accelerated the coordinated gene regulations and functional activities among non-electroactive bacteria.}, }
@article {pmid39431971, year = {2024}, author = {Wang, C and Su, Y and Shahriar, SMS and Li, Y and Xie, J}, title = {Emerging strategies for treating medical device and wound-associated biofilm infections.}, journal = {Microbial biotechnology}, volume = {17}, number = {10}, pages = {e70035}, pmid = {39431971}, issn = {1751-7915}, support = {Startup fund//University of Nebraska Medical Center/ ; R01GM138552//NIH/NIGMS/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; Humans ; *Wound Infection/microbiology/drug therapy ; Anti-Bacterial Agents/therapeutic use ; Equipment and Supplies/microbiology ; Bacterial Infections/drug therapy/microbiology/therapy ; Drug Delivery Systems ; }, abstract = {Bacterial infections represent a significant global threat to human health, leading to considerable economic losses through increased healthcare costs and reduced productivity. One major challenge in treating these infections is the presence of biofilms - structured bacterial communities that form protective barriers, making traditional treatments less effective. Additionally, the rise of antibiotic-resistant bacteria has exacerbated treatment difficulties. To address these challenges, researchers are developing and exploring innovative approaches to combat biofilm-related infections. This mini-review highlights recent advancements in the following key areas: surface anti-adhesion technologies, electricity, photo/acoustic-active materials, endogenous mimicking agents, and innovative drug delivery systems. These strategies aim to prevent biofilm formation, disrupt existing biofilms, and enhance the efficacy of antimicrobial treatments. Currently, these approaches show great potential for applications in medical fields such as medical device and wound - associated biofilm infections. By summarizing these developments, this mini-review provides a comprehensive resource for researchers seeking to advance the management and treatment of biofilm-associated infections.}, }
@article {pmid39429208, year = {2024}, author = {Rajangam, SL and Leela, KV and Jayaraman, M and Sabarathinam, S and Narasimhan, MK}, title = {Effect of amikacin-humic acid combination on Acinetobacter baumannii biofilm: an in vitro and in silico study.}, journal = {Future microbiology}, volume = {19}, number = {18}, pages = {1573-1585}, doi = {10.1080/17460913.2024.2412431}, pmid = {39429208}, issn = {1746-0921}, mesh = {*Acinetobacter baumannii/drug effects/physiology ; *Biofilms/drug effects/growth &amp; development ; *Amikacin/pharmacology ; *Anti-Bacterial Agents/pharmacology ; Humans ; *Acinetobacter Infections/microbiology/drug therapy ; *Microbial Sensitivity Tests ; *Computer Simulation ; Microbial Viability/drug effects ; }, abstract = {Aim: Acinetobacter baumannii (AB) is a clinically important bacterial pathogen responsible for nosocomial infections. The biofilm-forming capability of these pathogens reduces the antibiotic penetration and its efficacy, thereby complicating the treatment. The current work aims to isolate the most potent biofilm-forming Acinetobacter species from clinical isolates of the patient samples and to evaluate the efficacy of the amikacin-humic acid combination against it.Methods: The combination effect of Amikacin-Humic (AMK-HUM) acid against the highest biofilm-producing A. baumannii SLMK001 was studied via in-vitro (microscopic analysis) and in-silico (Network Pharmacology) analysis.Results: The amikacin-humic acid combination significantly inhibited both the biofilm formation and cell viability of A. baumannii SLMK001. The images observed via Scanning Electron Microscope (SEM) showed a significant decrease in the biofilm matrix. Confocal Laser Scanning Microscope (CLSM) confirmed a reduction of the Z value of its three-dimensional structure. Further, the Network Pharmacology approach supported these experimental findings by identifying the key targets of the amikacin-humic acid combination against the biofilm pathways of A. baumannii.Conclusion: The in-vitro results aligned with the in-silico findings, indicating that the AMK-HUM combination is a promising treatment that significantly activates the key proteins against A. baumannii biofilm formation and pathogenesis.}, }
@article {pmid39428671, year = {2024}, author = {Yang, J and Mao, L and Gulfam, Y and Zeeshan, M and Wang, X and Fan, T}, title = {Effect of Acetic Acid on Biofilm Formation in Paracidovorax citrulli, Causal Agent of Bacterial Fruit Blotch.}, journal = {Journal of basic microbiology}, volume = {64}, number = {12}, pages = {e2400188}, pmid = {39428671}, issn = {1521-4028}, support = {//This study was supported by the Fund for Less Developed Regions of the National Science Foundation of China (Grant 32360695 and 52067019)./ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Acetic Acid/pharmacology ; *Plant Diseases/microbiology/prevention &amp; control ; Fruit/microbiology ; Comamonadaceae/drug effects/physiology/growth &amp; development ; DNA, Bacterial/genetics ; Culture Media/chemistry ; Polysaccharides, Bacterial/metabolism ; }, abstract = {The unique tissue structure of pathogenic bacteria biofilm plays an important role in its pathogenicity and bactericide resistance. Inhibition or destruction of biofilm formation of pathogenic bacteria is of great significance for the control of plant bacterial diseases. In this study, Paracidovorax citrulli was inoculated into KB medium containing acetic acid, and after shaking at 28°C and 55 r/min for 48 h, it was found that the content of extracellular polysaccharide, extracellular protein and extracellular DNA (eDNA) decreased with the increase of acetic acid concentration, which resulted in the decrease of biofilm formation, it is not even possible to form biofilms on plastic slides. When the final concentration of acetic acid in the culture medium was greater than or equal to 0.5 mg/mL, there was no biofilm on the plastic slides. Therefore, the use of acetic acid as an inhibitor of P. citrulli has a good potential for control of bacterial fruit blotch.}, }
@article {pmid39427717, year = {2024}, author = {Loera-Muro, A and Silva-Jara, J and Hernández, V and León-Montoya, H and Angulo, C}, title = {A perspective on nanomaterials against Campylobacter jejuni biofilm - New control strategies.}, journal = {Microbial pathogenesis}, volume = {197}, number = {}, pages = {107031}, doi = {10.1016/j.micpath.2024.107031}, pmid = {39427717}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Campylobacter jejuni/drug effects/physiology ; *Nanostructures/chemistry ; *Anti-Bacterial Agents/pharmacology ; Humans ; Virulence Factors ; Campylobacter Infections/microbiology/prevention &amp; control ; Host-Pathogen Interactions ; Metal Nanoparticles/chemistry ; }, abstract = {Campylobacter jejuni - a Gram-negative bacterium - is considered the fourth cause of diarrheic diseases that can form biofilms (mono and multi-species) or colonize pre-existing biofilms adhering to both, inert or biotic surfaces; its biofilms contribute to transmission through the food chain and survival under harsh environmental conditions. Thus, developing alternatives against this pathogen is compulsory. Nanomaterials have revolutionized the way of fighting infections related to biofilms due to their unique properties compared to traditional antibiotics. Nanomaterials have also been used against C. jejuni based on zinc, titanium, silver, molybdenum, magnesium, cobalt, erbium, lithium, nickel, hydroxide, polyethylene, graphene, lipids, chitosan, and poly(lactic-co-glycolic acid) (PLGA). Those organic and inorganic materials have synthesized nanoparticles, nanofillers, nanowires, nanoferrites, double layers, nanocomposites, and films that have encapsulated, entrapped, coated or doped molecules. Additionally, bare metal nanoparticles have been tested by their antimicrobial activity on planktonic and sessile forms. Therefore, the present review aimed to describe general biology, virulence factors, host-pathogen relationships and biofilm formation, as well as nanomaterials and nanoparticles fighting against C. jejuni biofilms. Considerations are presented and placed in perspective.}, }
@article {pmid39427346, year = {2024}, author = {Li, Y and Qin, M and Niu, W and Gao, C and Wang, Y and Han, S and Xia, X}, title = {Microplastics colonized by Hafnia paralvei through biofilm formation regulated by c-di-GMP and cAMP promote its spread in water.}, journal = {Aquatic toxicology (Amsterdam, Netherlands)}, volume = {276}, number = {}, pages = {107127}, doi = {10.1016/j.aquatox.2024.107127}, pmid = {39427346}, issn = {1879-1514}, mesh = {*Biofilms/drug effects ; *Cyclic AMP/metabolism ; *Cyclic GMP/analogs &amp; derivatives/metabolism ; *Microplastics/toxicity ; *Water Pollutants, Chemical/toxicity ; Polyvinyl Chloride/chemistry ; }, abstract = {Microplastics (MPs) colonized by pathogens pose significant risks to the environment and health of animals and humans, however, the strategies for pathogens colonization in MPs and the effects of its colonization on spread of pathogens have not been fully characterized. Here, we investigated the biofilm formation mechanism regulated by c-di-GMP in Hafnia paralvei Z11, and determined the effect of MPs colonized by H. paralvei Z11 on the spread of strain Z11. Overexpression of yhjH, a c-di-GMP phosphodiesterase gene, attenuated intracellular c-di-GMP level in strain Z11, leading to an increase in biofilm dispersal and a decrease in biofilm formation. Meanwhile, the decline of c-di-GMP inhibited the expression of cAMP phosphodiesterase genes, increasing the cAMP content and promoting bacterial motility, that was responsible for the increase of biofilm dispersal. Furthermore, the formation of biofilms by strain Z11 on MPs promotes its colonization, which contributes to its vertical and horizontal spread in water after colonizing polyvinyl chloride-MPs and polypropylene-MPs, respectively. Therefore, this study reveals, for the first time, MPs colonized by H. paralvei Z11 through biofilms regulated by crosstalk between c-di GMP and cAMP promote the spread of strain Z11 in water, which expands the understanding of colonization strategy of pathogens on MPs and its risk on spread of pathogens.}, }
@article {pmid39427170, year = {2024}, author = {Suárez-Rodríguez, B and Regueira-Iglesias, A and Blanco-Pintos, T and Sánchez-Barco, A and Vila-Blanco, N and Balsa-Castro, C and Carreira, MJ and Tomás, I}, title = {Randomised-crossover clinical trial on the substantivity of a single application of a gel containing chlorhexidine and o-cymen-5-ol on the oral biofilm and saliva.}, journal = {BMC oral health}, volume = {24}, number = {1}, pages = {1247}, pmid = {39427170}, issn = {1472-6831}, support = {2021-CE161//Lacer, S. A./ ; 2021-CE161//Lacer, S. A./ ; 2021-CE161//Lacer, S. A./ ; 2021-CE161//Lacer, S. A./ ; 2021-CE161//Lacer, S. A./ ; 2021-CE161//Lacer, S. A./ ; ED431G-2023/04; GRC2021/48//Xunta de Galicia - Conseller&#xed;a de Cultura, Educaci&#xf3;n, Formaci&#xf3;n Profesional e Universidades and the European Union (European Regional Development Fund)/ ; ED431G-2023/04; GRC2021/48//Xunta de Galicia - Conseller&#xed;a de Cultura, Educaci&#xf3;n, Formaci&#xf3;n Profesional e Universidades and the European Union (European Regional Development Fund)/ ; }, mesh = {Humans ; *Chlorhexidine/pharmacology/administration &amp; dosage ; *Biofilms/drug effects ; *Saliva/microbiology ; *Gels ; *Cross-Over Studies ; Adult ; Male ; Female ; *Anti-Infective Agents, Local/pharmacology/administration &amp; dosage ; *Dental Plaque/microbiology/drug therapy ; Young Adult ; Microscopy, Confocal ; Microbial Viability/drug effects ; }, abstract = {BACKGROUND: No clinical trials have evaluated the antimicrobial activity and substantivity of gel formulations containing chlorhexidine (CHX) and cymenol.<br><br>OBJECTIVE: To compare the in situ antimicrobial effect and substantivity of a new 0.20% CHX&#x2009;+&#x2009;cymenol gel (test) with the current 0.20% CHX gel formulation (control) on salivary flora and dental plaque biofilm up to seven hours after a single application.<br><br>METHODS: A randomised-crossover clinical trial was conducted with 29 orally healthy volunteers participating in the development of Experiments 1 (saliva) and 2 (dental plaque biofilm). All subjects participated in both experiments and were randomly assigned to receive either the test or control gels. Samples were collected at baseline and five minutes and one, three, five, and seven hours after a single application of the products. The specimens were processed using confocal laser scanning microscopy after staining with the LIVE/DEAD[&#xae;] BacLight&#x2122; solution. Bacterial viability (BV) was quantified in the saliva and biofilm samples. The BV was calculated using the DenTiUS Biofilm software.<br><br>RESULTS: In Experiment 1, the mean baseline BV was significantly reduced five minutes after application in the test group (87.00% vs. 26.50%; p&#x2009;<&#x2009;0.01). This effect was maintained throughout all sampling times and continued up to seven hours (40.40%, p&#x2009;<&#x2009;0.01). The CHX control followed the same pattern. In Experiment 2, the mean baseline BV was also significantly lower five minutes after applying the test gel for: (1) the total thickness of biofilm (91.00% vs. 5.80%; p&#x2009;<&#x2009;0.01); (2) the upper layer (91.29% vs. 3.94%; p&#x2009;<&#x2009;0.01); and (3) the lower layer (86.29% vs. 3.83%; p&#x2009;<&#x2009;0.01). The reduction of BV from baseline was observed for the full-thickness and by layers at all sampling moments and continued seven hours after application (21.30%, 24.13%, and 22.06%, respectively; p&#x2009;<&#x2009;0.01). Again, the control group showed similar results. No significant differences between test and control gels were observed in either saliva or dental plaque biofilm at any sampling time.<br><br>CONCLUSIONS: A 0.20% CHX&#x2009;+&#x2009;cymenol gel application demonstrates potent and immediate antimicrobial activity on salivary flora and de novo biofilm. This effect is maintained seven hours after application. Similar effects are obtained with a 0.20% CHX-only gel.}, }
@article {pmid39426972, year = {2024}, author = {de Celis, M and Modin, O and Arregui, L and Persson, F and Santos, A and Belda, I and Wilén, BM and Liébana, R}, title = {Community successional patterns and inter-kingdom interactions during granular biofilm development.}, journal = {NPJ biofilms and microbiomes}, volume = {10}, number = {1}, pages = {109}, pmid = {39426972}, issn = {2055-5008}, support = {245-2013-627//Svenska Forskningsr&#xe5;det Formas (Swedish Research Council Formas)/ ; 2018-01423//Svenska Forskningsr&#xe5;det Formas (Swedish Research Council Formas)/ ; FEMS-GO-2021-032//Federation of European Microbiological Societies (FEMS)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Sewage/microbiology ; *Bioreactors/microbiology ; Bacteria/classification/growth &amp; development/genetics ; Microbial Interactions ; Eukaryota/physiology ; Microbiota ; }, abstract = {Aerobic granular sludge is a compact and efficient biofilm process used for wastewater treatment which has received much attention and is currently being implemented worldwide. The microbial associations and their ecological implications occurring during granule development, especially those involving inter-kingdom interactions, are poorly understood. In this work, we monitored the prokaryote and eukaryote community composition and structure during the granulation of activated sludge for 343 days in a sequencing batch reactor (SBR) and investigated the influence of abiotic and biotic factors on the granule development. Sludge granulation was accomplished with low-wash-out dynamics at long settling times, allowing for the microbial communities to adapt to the SBR environmental conditions. The sludge granulation and associated changes in microbial community structure could be divided into three stages: floccular, intermediate, and granular. The eukaryotic and prokaryotic communities showed parallel successional dynamics, with three main sub-communities identified for each kingdom, dominating in each stage of sludge granulation. Although inter-kingdom interactions were shown to affect community succession during the whole experiment, during granule development random factors like the availability of settlement sites or drift acquired increasing importance. The prokaryotic community was more affected by deterministic factors, including reactor conditions, while the eukaryotic community was to a larger extent shaped by biotic interactions (including inter-kingdom interactions) and stochasticity.}, }
@article {pmid39426218, year = {2024}, author = {Oliulla, H and Mizan, MFR and Kang, I and Ha, SD}, title = {On-going issues regarding biofilm formation in meat and meat products: challenges and future perspectives.}, journal = {Poultry science}, volume = {103}, number = {12}, pages = {104373}, pmid = {39426218}, issn = {1525-3171}, mesh = {*Biofilms ; *Meat/microbiology ; *Food Microbiology ; *Meat Products/microbiology ; Animals ; Food Handling/methods ; Bacterial Physiological Phenomena ; }, abstract = {The meat industry has been significantly threatened by the risks of foodborne microorganisms and biofilm formation on fresh meat and processed products. A microbial biofilm is a sophisticated defensive mechanism that enables bacterial cells to survive in unfavorable environmental circumstances. Generally, foodborne pathogens form biofilms in various areas of meat-processing plants, and adequate sanitization of these areas is challenging owing to the high tolerance of biofilm cells to sanitization compared with their planktonic states. Consequently, preventing biofilm initiation and maturation using effective and powerful technologies is imperative. In this review, novel and advanced technologies that prevent bacterial and biofilm development via individual and combined intervention technologies, such as ultrasound, cold plasma, enzymes, bacteriocins, essential oils, and phages, were evaluated. The evidence regarding current technologies revealed in this paper is potentially beneficial to the meat industry in preventing bacterial contamination and biofilm formation in food products and processing equipment.}, }
@article {pmid39426117, year = {2025}, author = {Flores-Flores, AS and Vazquez-Guillen, JM and Bocanegra-Ibarias, P and Camacho-Ortiz, A and Tamez-Guerra, RS and Rodriguez-Padilla, C and Flores-Treviño, S}, title = {MALDI-TOF MS profiling to predict resistance or biofilm production in gram-positive ESKAPE pathogens from healthcare-associated infections.}, journal = {Diagnostic microbiology and infectious disease}, volume = {111}, number = {1}, pages = {116562}, doi = {10.1016/j.diagmicrobio.2024.116562}, pmid = {39426117}, issn = {1879-0070}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods ; Humans ; *Cross Infection/microbiology ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests/methods ; Gram-Positive Bacteria/drug effects/classification ; Gram-Positive Bacterial Infections/microbiology/diagnosis ; Drug Resistance, Multiple, Bacterial ; Pseudomonas aeruginosa/drug effects ; Drug Resistance, Bacterial ; }, abstract = {Antimicrobial resistance and biofilm production in healthcare-associated infections is a health issue worldwide. This study aimed to identify potential biomarker peaks for resistance or biofilm production in ESKAPE pathogens using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Antimicrobial susceptibility and biofilm production were assessed on selected isolates. Biomarker peaks were identified using MALDI Biotyper and ClinProTools software. Among resistant strains, 90.0 % were carbapenem-resistant Acinetobacter baumannii (CRAB), 39.0 % were methicillin-resistant Staphylococcus aureus (MRSA), 17.98 % were multidrug-resistant (MDR) Pseudomonas aeruginosa, 21.6 % were vancomycinresistant Enterococcus (VRE), and 2.55 % were carbapenem-resistant Enterobacterales (CRE). Biofilm production was 40.0 % in VRE and 45.8 % in MRSA. Although no potential biomarker peaks for biofilm production were detected, several potential biomarker peaks for drug resistance in VRE (n=5), MRSA (n=4), and MDR P. aeruginosa (n=4) were detected, suggesting avenues for the development of rapid diagnostic tools.}, }
@article {pmid39425525, year = {2024}, author = {Stewart, PS and Kim, J and James, G and Yi, F and Stechmiller, J and Weaver, M and Kelly, DL and Fisher, S and Schultz, G and Lyon, D}, title = {Association of biofilm and microbial metrics with healing rate in older adults with chronic venous leg ulcers.}, journal = {Wound repair and regeneration : official publication of the Wound Healing Society [and] the European Tissue Repair Society}, volume = {32}, number = {6}, pages = {858-871}, pmid = {39425525}, issn = {1524-475X}, support = {UL1TR001427/NH/NIH HHS/United States ; R01NR016986/NR/NINR NIH HHS/United States ; 2018562//National Science Foundation/ ; NRF-2022R1C1C1006659//National Research Foundation of Korea/ ; ECCS-2025391//Montana Nanotechnology Facility/ ; R01 NR016986/NR/NINR NIH HHS/United States ; UL1 TR001427/TR/NCATS NIH HHS/United States ; 202016116//M. J. Murdock Charitable Trust/ ; }, mesh = {Humans ; *Biofilms/growth &amp; development ; *Wound Healing/physiology ; Female ; *Varicose Ulcer/microbiology/physiopathology/therapy ; Male ; Aged ; *Debridement/methods ; Chronic Disease ; Aged, 80 and over ; Wound Infection/microbiology ; Middle Aged ; }, abstract = {The presence of microbial biofilms in many human chronic wounds led to the hypothesis that biofilms delay healing of these wounds. We tested this hypothesis in a population of 117 older individuals with venous leg ulcers who were receiving standardised therapy, including frequent debridement. Debridement specimens were analysed for the amount of bacterial biomass by two independent methods: a microscopic approach that scored the relative size and number of bacterial aggregates, interpreted as a biofilm metric, and conventional enumeration by agar plating for viable bacteria. The plating protocol yielded three distinct values: the total viable bacterial count, bleach-tolerant bacteria, and the log reduction in viable bacteria upon bleach treatment. Wound healing rates over an 8-week observation period were calculated as the rate of decrease of the equivalent diameter of the wound. There was no statistically significant association between wound healing and the biofilm metric in any of the three analyses performed (p ≥0.15). In all three statistical tests, wound healing was associated with the log reduction caused by bleach treatment (p ≤0.004); wounds that harboured bacteria that were more bleach-susceptible healed more slowly. A refinement of the model of chronic wound infection pathogenesis is proposed in which dormant bacteria constitute a persistent nidus and outgrowth of metabolically active cells impairs healing. This model constitutes a new hypothesis as metabolic activity was not directly measured in this investigation.}, }
@article {pmid39425255, year = {2025}, author = {Khan, SN and Ribeiro-Vidal, H and Virto, L and Bravo, E and Nuevo, P and Koldsland, OC and Hjortsjö, C and Sanz, M}, title = {The Decontamination Effect of an Oscillating Chitosan Brush Compared With an Ultrasonic PEEK-Tip: An In Vitro Study Using a Dynamic Biofilm Model.}, journal = {Clinical oral implants research}, volume = {36}, number = {1}, pages = {73-81}, doi = {10.1111/clr.14360}, pmid = {39425255}, issn = {1600-0501}, mesh = {*Biofilms/drug effects ; *Chitosan/pharmacology ; *Polyethylene Glycols/pharmacology ; *Polymers/pharmacology ; *Decontamination/methods ; In Vitro Techniques ; Benzophenones ; Fusobacterium nucleatum/drug effects ; Ketones/pharmacology ; Microscopy, Electron, Scanning ; Surface Properties ; Dental Implants/microbiology ; Aggregatibacter actinomycetemcomitans/drug effects ; Porphyromonas gingivalis/drug effects ; Streptococcus oralis/drug effects ; Actinomyces/drug effects ; Veillonella ; }, abstract = {OBJECTIVES: This study aimed to assess the effect of an oscillating chitosan brush (OCB) compared with an ultrasonic device with PEEK tip (US-PEEK) for mechanical implant surface decontamination using an in vitro model combining 3D models and a validated dynamic multispecies biofilm.<br><br>MATERIALS AND METHODS: A multispecies biofilm using six bacterial strains (Streptococcus oralis, Veillonella parvula, Actinomyces naeslundii, Fusobacterium nucleatum, Porphyromonas gingivalis, and Aggregatibacter actinomycetemcomitans) was seeded on dental implants with machined and sandblasted, large-grit and acid-etched (SLA) surfaces. These were installed in 3D models depicting peri-implant defect. Mechanical decontamination was performed for 120&#x2009;s using either an OCB or a US-PEEK. A negative control group received no treatment. Scanning electron microscopy (SEM) was used to evaluate the bacterial composition and quantitative PCR (qPCR) analyzed the number of each bacterial species [colony-forming units per milliliter (CFU/mL)].<br><br>RESULTS: Well-structured biofilms with a dense microbial distribution were observed on the negative control implants after 72&#x2009;h. qPCR following mechanical decontamination showed a scarce bacterial reduction in the OCB group. The US-PEEK group exhibited a significant decrease in bacterial species compared to both OCB and control groups (p&#x2009;<&#x2009;0.05). A biofilm removal effect was also observed in the OCB group for the machined implant surfaces.<br><br>CONCLUSION: In vitro assessment using an anatomical 3D model showed that mechanical decontamination effectively reduced biofilm. The US-PEEK group demonstrated biofilm reduction on the SLA surface, while the OCB group showed a reduction on the machined implant surface. Additionally, the US-PEEK group demonstrated greater efficacy in reducing bacterial numbers.}, }
@article {pmid39424595, year = {2024}, author = {De Padua, JC and Kikuchi, T and Sakakibara, F and De Leon, AM and Bungihan, ME and Ueno, K and Dela Cruz, TEE and Ishihara, A}, title = {Novel compound, pleuropyronine, and other polyketides isolated from the edible mushroom Pleurotus ostreatus suppress bacterial biofilm formation.}, journal = {Bioscience, biotechnology, and biochemistry}, volume = {89}, number = {1}, pages = {11-21}, doi = {10.1093/bbb/zbae148}, pmid = {39424595}, issn = {1347-6947}, support = {//Department of Science &amp; Technology-Science Education Institute-Foreign Graduate Scholarship (DOST-FGS)/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Pleurotus/chemistry ; *Polyketides/pharmacology/chemistry/isolation &amp; purification ; Anti-Bacterial Agents/pharmacology/isolation &amp; purification/chemistry ; Microbial Sensitivity Tests ; Pyrones/pharmacology/isolation &amp; purification/chemistry ; }, abstract = {An increase in the number of drug-resistant microbes is a major threat to human health. Bacterial drug resistance is mostly mediated by biofilm formation. In this study, the culture filtrate from the edible mushroom, Pleurotus ostreatus, was fractionated to isolate compounds that inhibit the biofilm formation of six pathogenic bacteria. Notably, we isolated compounds 1-6 using bioassay-guided chromatographic separations. Spectroscopic and X-ray diffraction analyses identified 1 as a novel fused bicyclic pyrone-furan, named pleuropyronine, whereas 2-6 were known polyketides. Pleuropyronine inhibited biofilm formation in four Gram-negative bacteria, with IC50 values ranging from 5.4 to 8.7 µg/mL, whereas 2-6 exhibited IC50 values between 1.0 and 5.3 µg/mL against five bacteria. Additionally, pleuropyronine bioactivity was confirmed by the inhibition of exopolysaccharide and biofilm formation induced by C6-homoserine lactone. Thus, this may serve as a pioneering study on the pharmacological potential of isolated compounds, offering valuable insights for future research.}, }
@article {pmid39423986, year = {2024}, author = {Li, Y and Li, Y and Gao, H and Liu, J and Liang, H}, title = {Edible thermosensitive chitosan/hydroxypropyl β-cyclodextrin hydrogel with natural licoricidin for enhancing oral health: Biofilm disruption and demineralization prevention.}, journal = {International journal of biological macromolecules}, volume = {282}, number = {Pt 1}, pages = {136647}, doi = {10.1016/j.ijbiomac.2024.136647}, pmid = {39423986}, issn = {1879-0003}, mesh = {*Biofilms/drug effects ; *Chitosan/chemistry/pharmacology ; *Hydrogels/chemistry/pharmacology ; *2-Hydroxypropyl-beta-cyclodextrin/chemistry/pharmacology ; *Oral Health ; *Streptococcus mutans/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Staphylococcus aureus/drug effects ; Humans ; Tooth Demineralization/prevention &amp; control ; Temperature ; Animals ; }, abstract = {Dental caries, a widespread and significantly detrimental health condition, is characterized by demineralization, pain, compromised tooth functionality, and various other adverse effects. Licoricidin (LC), a natural isoflavonoid, demonstrates potent antimicrobial properties for maintaining oral health. However, its practical application is significantly hindered by its limited water solubility and susceptibility to removal within the oral environment. To tackle this issue, we developed a delivery oral system by an edible thermosensitive chitosan- disodium beta-glycerol phosphate pentahydrate (CS/β-GP) hydrogel to load LC/Hydroxypropyl beta-cyclodextrin (HP-β-CD) inclusion complexes. These hydrogels (LC/HP-β-CD/CS/β-GP) could solidify rapidly at oral temperature and sustainably release LC, thereby preventing its rapid clearance from the oral cavity. We confirmed the significant antibacterial activity of this hydrogel against Streptococcus mutans and Staphylococcus aureus. Additionally, the HP-β-CD combination enhanced LC to penetrate bacterial biofilms and inhibit biofilm growth, leading to leakage of cellular proteins and DNA. Additionally, we studied the effect of LC/HP-β-CD/CS/β-GP on intracellular ROS levels and MMP, comprehensively exploring its antimicrobial mechanism. Furthermore, LC/HP-β-CD/CS/β-GP exhibited the ability to inhibit demineralization and demonstrated excellent biocompatibility. In summary, this study presented a safer approach to oral delivering bioactive substances, offering a promising strategy for enhanced oral health and safety.}, }
@article {pmid39423969, year = {2024}, author = {Wu, S and Huang, Y and Wu, M and Chen, H and Wang, B and Amoah, K and Cai, J and Jian, J}, title = {Identification of a cellular role of hemolysin co-regulatory protein (Hcp) in Vibrio alginolyticus modulating substrate metabolism and biofilm formation by cAMP-CRP.}, journal = {International journal of biological macromolecules}, volume = {282}, number = {Pt 1}, pages = {136656}, doi = {10.1016/j.ijbiomac.2024.136656}, pmid = {39423969}, issn = {1879-0003}, mesh = {*Vibrio alginolyticus/metabolism ; *Biofilms/growth &amp; development ; *Cyclic AMP/metabolism ; *Bacterial Proteins/metabolism/genetics ; *Cyclic AMP Receptor Protein/metabolism/genetics ; Gene Expression Regulation, Bacterial ; Glucose/metabolism ; Hemolysin Proteins/metabolism ; }, abstract = {Cyclic AMP (cAMP) and cAMP receptor protein (CRP) system controls catabolic enzyme expression based on metabolite concentrations in bacteria. Hemolysin co-regulatory protein (Hcp) is well known as a molecular chaperone for virulence factor secretion of the type VI secretion system (T6SS). However, the intracellular role of Hcp involving in bacterial physiological processes remains unknown. To clarify that, we constructed a single hcp mutant strain and analyzed their effects on the physiological processes of Vibrio alginolyticus. The omics results revealed the extensive involvement of Hcp in the catabolic metabolism in bacteria. Simultaneously, Hcp1 and Hcp2 played opposing regulatory roles on the bacterial growth, biofilm formation, and intracellular cAMP-CRP levels during cultivation in a glucose medium. Furthermore, the interacting protein screening and co-immunoprecipitation (Co-IP) assays confirmed that the glucose-specific phosphoenolpyruvate (PEP)-phosphotransferase system (PTS) enzyme IIA component (EIIA[glc]) was a key interacting partner with Hcp proteins as well as class I adenylyl cyclase (AC-I) in Vibrio alginolyticus. These results indicated that, to achieve cellular homeostasis, Hcp1 and Hcp2 might exert antagonistic and synergistic effects, respectively, on the interaction between EIIA[glc] and AC thus cooperatively regulating intracellular cAMP-CRP production.}, }
@article {pmid39423901, year = {2024}, author = {Pasquarelli, F and Oliva, G and Mariniello, A and Buonerba, A and Zorpas, AA and Ng, HY and Belgiorno, V and Naddeo, V and Zarra, T}, title = {Integration of Moving Bed Biofilm Reactor (MBBR) and algal PhotoBioReactors (aPBR) for achieving carbon neutrality in wastewater treatment.}, journal = {The Science of the total environment}, volume = {955}, number = {}, pages = {177012}, doi = {10.1016/j.scitotenv.2024.177012}, pmid = {39423901}, issn = {1879-1026}, mesh = {*Waste Disposal, Fluid/methods ; *Wastewater ; *Biofilms ; *Photobioreactors ; Carbon ; Bioreactors ; Water Pollutants, Chemical/analysis ; Toluene ; }, abstract = {Carbon neutrality is a primary goal for wastewater treatment plants (WWTPs), as they are responsible for significant greenhouse gas (GHG) emissions as well as unpleasant odour emissions. The paper shows a new modular biotechnology that enables simultaneous treatment of gaseous emissions and biofixation of CO2. A comparative assessment of system performances in removing target pollutants (toluene, p-xylene and hydrogen sulphide) was implemented. Results showed that the highest removal efficiency (RE) was recorded for the toluene, equaling 99.9 ± 0.1 %, for an inlet load (IL) of 9.91 ± 3.44 g m[-3] d[-1]. During the experimental tests regarding hydrogen sulphide removal, the system recorded the highest CO2 assimilation, equal to -3.03 ± 0.93 g m[-3] d[-1]. However, this assimilation rate did not correspond to the maximum volumetric biomass productivity (MVBP), equal to 1.3 g L[-1] d[-1], recorded with toluene treatment, with a maximum lipid productivity (MLP) of 450 mg L[-1] d[-1]. The results demonstrated the complete adaptability of the investigated system, which can help to fill the gaps in the current technological landscape, providing an innovative biotechnology that can be directly implemented and environmentally sustainable.}, }
@article {pmid39423786, year = {2025}, author = {Ren, H and Wang, R and Ying, L and Iyobosa, E and Chen, G and Zang, D and Tong, M and Li, E and Nerenberg, R}, title = {Removal of sulfamethoxazole in an algal-bacterial membrane aerated biofilm reactor: Microbial responses and antibiotic resistance genes.}, journal = {Water research}, volume = {268}, number = {Pt A}, pages = {122595}, doi = {10.1016/j.watres.2024.122595}, pmid = {39423786}, issn = {1879-2448}, mesh = {*Biofilms/drug effects ; *Bioreactors ; *Sulfamethoxazole/pharmacology ; Drug Resistance, Microbial/genetics ; Anti-Bacterial Agents/pharmacology ; Bacteria/genetics/metabolism/drug effects ; Waste Disposal, Fluid ; Wastewater/microbiology ; }, abstract = {Antibiotics are frequently detected in wastewater, but often are poorly removed in conventional wastewater treatment processes. Combining microalgal and nitrifying bacterial processes may provide synergistic removal of antibiotics and ammonium. In this research, we studied the removal of the antibiotic sulfamethoxazole (SMX) in two different reactors: a conventional nitrifying bacterial membrane aerated biofilm reactor (bMABR) and algal-bacterial membrane aerated biofilm reactor (abMABR) systems. We investigated the synergistic removal of antibiotics and ammonium, antioxidant activity, microbial communities, antibiotic resistance genes (ARGs), mobile genetic elements (MGEs), and their potential hosts. Our findings show that the abMABR maintained a high sulfamethoxazole (SMX) removal efficiency, with a minimum of 44.6 % and a maximum of 75.8 %, despite SMX inhibition, it maintained a consistent 25.0 % ammonium removal efficiency compared to the bMABR. Through a production of extracellular polymeric substances (EPS) with increased proteins/polysaccharides (PN/PS), the abMABR possibly allowed the microalgae-bacteria consortium to protect the bacteria from SMX inactivation. The activity of antioxidant enzymes caused by SMX was reduced by 62.1-98.5 % in the abMABR compared to the bMABR. Metagenomic analysis revealed that the relative abundance of Methylophilus, Pseudoxanthomonas, and Acidovorax in the abMABR exhibited a significant positive correlation with SMX exposure and reduced nitrate concentrations and SMX removal. Sulfonamide ARGs (sul1 and sul2) appeared to be primarily responsible for defense against SMX stress, and Hyphomicrobium and Nitrosomonas were the key carriers of ARGs. This study demonstrated that the abMABR system has great potential for removing SMX and reducing the environmental risks of ARGs.}, }
@article {pmid39423625, year = {2024}, author = {Mishra, S and Ren, Y and Sun, X and Lian, Y and Singh, AK and Sharma, N and Shikhar, KC}, title = {Microplastics-biofilm in aquatic ecosystem: Formation, pollutants complexation, greenhouse gas emission and ecotoxicology.}, journal = {Journal of environmental management}, volume = {370}, number = {}, pages = {122930}, doi = {10.1016/j.jenvman.2024.122930}, pmid = {39423625}, issn = {1095-8630}, mesh = {*Biofilms ; *Greenhouse Gases ; *Microplastics/toxicity ; *Ecosystem ; *Ecotoxicology ; Water Pollutants, Chemical/toxicity ; }, abstract = {The omnipresent microplastics (MPs) have gradually become a significant environmental problem due to its adverse consequences for ecological systems. MPs serve as substrates for biofilms colonization, which enhances adsorption of harmful contaminants on MPs surface in the aquatic ecosystem. The present study provides a critical discussion on the mechanism involved in MPs-biofilm formation, microbial colonization and the robust factors influencing the process in the aquatic ecosystem. Subsequently, the impact of MPs-biofilm on adsorption of inorganic and organic contaminants is explored. The ecological significance of MPs-biofilm associated pollutant complex for promoting greenhouse gases (GHGs) emissions from aquatic ecosystem is extensively discussed for understanding the climatic risk. Furthermore, the discussion is extended over ecotoxicological impact of MPs-biofilm on aquatic biodiversity and humans. The protective extracellular polymeric substances secreted by colonised bacteria over MPs during biofilm formation creates sticky MPs surface for heteroaggregates formation with swift adsorption of chemical compounds and microorganisms. MPs with functional aromatic groups facilitate the bacterial adhesion on the surface, but affect formation of biofilm. Alternatively, MPs-biofilm promotes the Mn and Fe hydrous oxides formation that can co-precipitate with heavy metal ions and facilitate in remediation measures. However, MPs biodegradation generates GHGs emission per unit mass, comparably more from freshwater than marine ecosystem. Considering the toxicity, MPs-biofilm induces the oxidative response in fishes, causing painful death and thus, destroys aquatic biodiversity. This study will be useful to address MPs-biofilm associated pollution scenario via trace, test and treat strategy involving future engineering research framework for ecological restoration.}, }
@article {pmid39423506, year = {2024}, author = {Lin, S and Li, X and Zhang, W and Shu, G and Li, H and Xu, F and Lin, J and Peng, G and Zhang, L and Fu, H}, title = {Encapsulation nanoarchitectonics of glabridin with sophorolipid micelles for addressing biofilm hazards via extracellular polymeric substance permeation and srtA gene suppression.}, journal = {Ecotoxicology and environmental safety}, volume = {286}, number = {}, pages = {117150}, doi = {10.1016/j.ecoenv.2024.117150}, pmid = {39423506}, issn = {1090-2414}, mesh = {*Biofilms/drug effects ; *Staphylococcus aureus/drug effects ; *Extracellular Polymeric Substance Matrix ; *Isoflavones/chemistry/pharmacology ; *Phenols/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Micelles ; Bacterial Proteins ; Microbial Sensitivity Tests ; Nanoparticles/chemistry ; Lecithins/chemistry ; Oleic Acids ; }, abstract = {BACKGROUND: Biofilm, a common drug-resistant phenotype of Staphylococcus aureus (S. aureus), demonstrates significant drug resistance and recurrence due to its extracellular polymeric substance (EPS) barrier and subsequent bacterial migration. Hence, there is an urgent need for effective solutions to mitigate the hazards posed by biofilms.<br><br>RESULT: This study developed a stable, low-toxicity multifunctional nanomicelle, GLA@SOL/EYL, by encapsulating glabridin (GLA) using sophorolipid (SOL) and egg yolk lecithin (EYL). Optimizations were performed for the hydration medium, the ratio of carrier materials to GLA, and EYL additions. GLA@SOL/EYL exhibited a particle size of 122.1 &#xb1; 0.8&#x202f;nm and a surface potential of -66.4 &#xb1; 1.7&#x202f;mV, endowing it with the ability to permeate biofilms EPS effectively. GLA@SOL/EYL encapsulated 98.3 &#xb1; 1.2&#x202f;% of GLA and demonstrated a slow-release effect, significantly enhancing the bioavailability of GLA. The addition of EYL reduced the hemolytic toxicity of GLA@SOL/EYL and improved its encapsulation rate and stability. GLA@SOL/EYL reduced the minimum inhibitory concentration of GLA to 8&#x202f;&#x3bc;g/mL and extended its inhibitory effect at low concentrations by rapidly disrupting the structural integrity of S. aureus. GLA@SOL/EYL may penetrate biofilms to disperse EPS and remove twice as much biofilm as GLA alone, thereby eliminating 99.99&#x202f;% of S. aureus within biofilms, compared to 99&#x202f;% bactericidal efficacy of GLA. Additionally, GLA@SOL/EYL inhibited 63.8 &#xb1; 1.8&#x202f;% of biofilm formation by affecting the expression of the srtA gene, thereby reducing the expression of cell wall-anchoring protein genes. In contrast, the biofilm inhibition rates of GLA and blank micelles were less than 10&#x202f;%.<br><br>CONCLUSION: GLA@SOL/EYL utilizes the nanoparticle effect to penetrate biofilms and deliver antimicrobial GLA. The SOL disperses the biofilm matrix while GLA is released to kill S. aureus, preventing bacterial dissemination and colonization. Thus, GLA@SOL/EYL presents an innovative strategy for effectively eradicating S. aureus biofilms and preventing new hazards in a one-step approach.}, }
@article {pmid39422496, year = {2024}, author = {Lee, KM and Jaeger, VW}, title = {Adsorption of Staphylococcus aureus biofilm associated compounds on silica probed with molecular dynamics simulations.}, journal = {Biointerphases}, volume = {19}, number = {5}, pages = {}, doi = {10.1116/6.0003870}, pmid = {39422496}, issn = {1559-4106}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Silicon Dioxide/chemistry ; *Molecular Dynamics Simulation ; *Staphylococcus aureus/physiology/drug effects ; Adsorption ; Hydrogen-Ion Concentration ; Acetylglucosamine/chemistry/metabolism ; }, abstract = {Staphylococcus aureus (S. aureus) is a potentially pathogenic bacterium that commonly colonizes surfaces through the formation of biofilms. Silica glass is a common material in the built environment, especially in laboratory and medical spaces. The chemical and physical mechanisms by which S. aureus initially adheres to surfaces are unclear. In this study, the adsorption of several S. aureus biofilm associated compounds on silica is probed using molecular dynamics simulations. Model compounds containing a phosphorylated backbone, N-acetylglucosamine (GlcNAc), or D-alanine (D-Ala) were simulated across a range of pH. GlcNAc adsorption is unfavorable and insensitive to pH. D-Ala adsorption is unfavorable across the range of tested pH. Phosphorylated backbone adsorption is unfavorable at low pH but favorable at high pH. Adsorbate titration and solution salt concentration were probed to establish effects of molecular charge and charge screening. Hydrogen bonding between compounds and the silica surface is a key factor for stronger adsorption. The findings of this study are important for the rational design of improved silica surfaces through chemical functionalization or through the application of optimal chemical disinfectants that discourage the initial stages of biofilm growth.}, }
@article {pmid39422163, year = {2024}, author = {Wang, Y and Guo, W and Zhang, K and Liu, Z and Dai, X and Qiao, Z and Ding, X and Zhao, N and Xu, FJ}, title = {Biomimetic Electrodynamic Metal-Organic Framework Nanosponges for Augmented Treatment of Biofilm Infections.}, journal = {Advanced science (Weinheim, Baden-Wurttemberg, Germany)}, volume = {11}, number = {46}, pages = {e2408442}, pmid = {39422163}, issn = {2198-3844}, support = {52303172//National Natural Science Foundation of China/ ; 52361165659//National Natural Science Foundation of China/ ; 52173271//National Natural Science Foundation of China/ ; 52221006//National Natural Science Foundation of China/ ; 2022YFC2403200//National Key Research and Development Program of China/ ; 2214074//Beijing Natural Science Foundation/ ; BJJWZYJH01201910010024//Beijing Outstanding Young Scientist Program/ ; Z191100006619099//Beijing Municipal Science and Technology Project/ ; JD2419//Fundamental Research Funds for the Central Universities/ ; KQYY//Animal Ethics Committee of Capital Medical University/ ; 202209//Animal Ethics Committee of Capital Medical University/ ; 003//Animal Ethics Committee of Capital Medical University/ ; }, mesh = {*Metal-Organic Frameworks/chemistry/pharmacology ; Animals ; *Biofilms/drug effects ; Mice ; *Staphylococcus aureus/drug effects ; *Disease Models, Animal ; Staphylococcal Infections/drug therapy ; Anti-Bacterial Agents/pharmacology/chemistry ; Biomimetics/methods ; Reactive Oxygen Species/metabolism ; Biomimetic Materials/chemistry/pharmacology ; }, abstract = {Electrodynamic therapy (EDT) is a promising alternative approach for antibacterial therapy, as reactive oxygen species (ROS) are produced efficiently in response to an electric field without relying on endogenous H2O2 and O2. However, the inherent toxicity of metallic catalysts and numerous bacterial toxins during the therapeutic process still hinder its development. Herein, biomimetic metal-organic (MOF@EV) nanosponges composed of ginger-derived extracellular vesicles (EVs), and electrodynamic metal-organic frameworks (MOFs) are developed for the eradication of bacterial infections and the absorption of toxins. The prolonged circulation time of MOF@EV in vivo facilitates their accumulation at infection sites. More interestingly, MOF@EV can behave as nanosponges and effectively prevent host cells from binding to bacterial toxins, thereby reducing damage to cells. Subsequently, the MOF@EV nanosponges are discovered to work as electro-sensitizers, which is confirmed through both theoretical calculation and experimental verification. As a result, ROS is continuously produced under the electric field to achieve effective EDT-mediated bacterial eradication. Meanwhile, the treatment process of MOF@EV in vivo is visualized in mice infected with luciferase-expressing Staphylococcus aureus (S. aureus), and excellent biofilm eradication capacity and detoxification efficiency are demonstrated in a subcutaneous abscess model. This work provides a promising strategy for the treatment of bacterial infections.}, }
@article {pmid39420484, year = {2024}, author = {Ibarra, Y and Marenco, PJ and Centlivre, JP and Hedlund, BP and Rademacher, LK and Greene, SE and Bottjer, DJ and Corsetti, FA}, title = {A Biofilm Channel Origin for Vermiform Microstructure in Carbonate Microbialites.}, journal = {Geobiology}, volume = {22}, number = {5}, pages = {e12623}, doi = {10.1111/gbi.12623}, pmid = {39420484}, issn = {1472-4669}, support = {EAR 2038374//National Science Foundation/ ; EAR 2038420//National Science Foundation/ ; EAR 2038377//National Science Foundation/ ; EAR 2221249//National Science Foundation/ ; }, mesh = {*Biofilms/growth &amp; development ; *Carbonates/metabolism ; *Fossils ; *Porifera/microbiology/physiology ; Animals ; Seawater/microbiology/chemistry ; Geologic Sediments/microbiology ; }, abstract = {A three-dimensional tubular fabric known as "vermiform microstructure" in Phanerozoic and Neoproterozoic carbonate microbialites has been hypothesized to represent the body fossil of nonspicular keratose demosponges. If correct, this interpretation extends the sponge body fossil record and origin of animals to ~890 Ma. However, the veracity of the keratose sponge interpretation for vermiform microstructure remains in question, and the origin of the tubular fabric is enigmatic. Here we compare exceptionally well-preserved microbialite textures from the Upper Triassic to channel networks created by modern microbial biofilms. We demonstrate that anastomosing channel networks of similar size and geometries are produced by microbial biofilms in the absence of sponges, suggesting the origin for vermiform microstructure in ancient carbonates is not unique to sponges and perhaps best interpreted conservatively as likely microbial in origin. We present a taphonomic model of early biofilm lithification in seawater with anomalously high carbonate saturation necessary to preserve delicate microbial textures. This work has implications for the understanding of three-dimensional biofilm architecture that goes beyond the current micro-scale observations available from living biofilm experiments and suggests that biofilm channel networks have an extensive fossil record.}, }
@article {pmid39420448, year = {2024}, author = {Udeh, CU and Amaechi, BT and Abdul-Azees, PA and Obiefuna, AC and Lin, CY and IftiKhar, N and Mankar, S and Omosebi, TO and Gohil, T}, title = {Influence of nanohydroxyapatite mouthwash on the growth of Candida albicans biofilm on milled denture surfaces: An in vitro study.}, journal = {Journal of prosthodontics : official journal of the American College of Prosthodontists}, volume = {}, number = {}, pages = {}, doi = {10.1111/jopr.13965}, pmid = {39420448}, issn = {1532-849X}, abstract = {PURPOSE: There is a need for effective solutions for the persistent prevalence of denture stomatitis (DS) in denture-wearing populations. This study assessed the impact of nanohydroxyapatite (nanoHAP) nanoparticles on Candida albicans biofilm formation on milled polymethylmethacrylate (PMMA) denture bases.<br><br>MATERIALS AND METHODS: Acquired salivary pellicle was formed on disks milled from a prepolymerized PMMA puck. The disks were assigned to two groups, A (n&#xa0;=&#xa0;18) and B (n&#xa0;=&#xa0;18), and each group was further subdivided into three subgroups (6/subgroup), each treated with either Polident solution (antibacterial denture cleanser), nanoHAP mouthwash, or distilled water. Disks in group A subgroups were soaked in their respective treatment solutions for 8&#xa0;h, followed by biofilm formation on the&#xa0;disk for 24&#xa0;h. Disks in group B subgroups had C. albicans biofilm formed on them for 24&#xa0;h, followed by soaking in their respective treatment solutions for 8&#xa0;h. Biofilm thickness, biomass, and live/dead cell ratio were determined using a&#xa0;confocal laser scanning microscope. Biofilm morphology was examined with a&#xa0;scanning electron microscope (SEM). Data were analyzed by ANOVA and Tukey-Kramer multiple comparisons (&#x3b1;&#xa0;=&#xa0;0.05).<br><br>RESULTS: In group A, nanoHAP mouthwash displayed significant anti-adhesive properties. In group B, biofilm biomass and thickness significantly decreased (p&#xa0;<&#xa0;0.05), with the nanoHAP showing the most substantial reduction in existing biofilm compared to other solutions, but it did not significantly affect cell viability.<br><br>CONCLUSIONS: This study demonstrated the efficacy of nanoHAP mouthwash in inhibiting C. albicans biofilm formation when used as a storage medium for acrylic dentures. It suggests its potential clinical application for preventing denture stomatitis in patients.}, }
@article {pmid39420363, year = {2024}, author = {Everly, V and Waturangi, DE and Papuangan, N and Nurhasanah,  and Julyantoro, PGS}, title = {Metabolite from supernatant of soil and plant-associated bacteria control biofilm of fish pathogens.}, journal = {BMC research notes}, volume = {17}, number = {1}, pages = {311}, pmid = {39420363}, issn = {1756-0500}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Soil Microbiology ; Aeromonas hydrophila/drug effects/physiology ; Animals ; Chromobacterium/drug effects/physiology/metabolism ; Quorum Sensing/drug effects ; Vibrio/drug effects/physiology ; Fishes/microbiology ; Anti-Bacterial Agents/pharmacology ; Rhizosphere ; Indonesia ; Bacteria/drug effects/metabolism ; Fish Diseases/microbiology ; }, abstract = {OBJECTIVES: This research aimed to identify and quantify the antibiofilm activity of bioactive compounds from bacteria isolated from rhizosphere and nodule butterfly pea (Clitoria ternatea), rhizosphere clove afo 3 (Syzygium aromaticum), nodule mimosa (Mimosa pudica L.), and soil from gold mining land which were recovered from Ternate, Tidore, Obi Island, and Marotai Island, Eastern part of Indonesia.<br><br>RESULTS: Eight supernatants from soil and plant-associated bacteria were found to have quorum quenching activity against Chromobacterium violaceum. All supernatants exhibited antibiofilm activity against biofilm formed by Aeromonas hydrophila and Vibrio harveyi. The supernatant of FT5 showed the highest activity in disrupting (66.59%) and inhibiting (85.63%) the biofilm of A. hydrophila. For V. harveyi, the supernatant of PTM3 showed the highest disruption activity (72.61%), whileRCA7 showed the highest inhibition activity(75.68%). The Gas Chromatography-Mass Spectrometry (GC-MS) identified fatty acids, ester, and diketopiperazine as the compounds related to the antibiofilm activity. Molecular identification revealed that the isolates belong to the genera Bacillus, Priestia, and Chryseobacterium.}, }
@article {pmid39420209, year = {2024}, author = {Van Roy, Z and Arumugam, P and Bertrand, BP and Shinde, DD and Thomas, VC and Kielian, T}, title = {Tissue niche influences immune and metabolic profiles to Staphylococcus aureus biofilm infection.}, journal = {Nature communications}, volume = {15}, number = {1}, pages = {8965}, pmid = {39420209}, issn = {2041-1723}, support = {P30 GM110768/GM/NIGMS NIH HHS/United States ; R01 NS107369/NS/NINDS NIH HHS/United States ; R01 AI169788/AI/NIAID NIH HHS/United States ; P30 CA036727/CA/NCI NIH HHS/United States ; P01 AI083211/AI/NIAID NIH HHS/United States ; P20 GM103427/GM/NIGMS NIH HHS/United States ; }, mesh = {*Biofilms/growth &amp; development/drug effects ; Animals ; *Staphylococcus aureus/immunology/physiology ; *Staphylococcal Infections/immunology/microbiology/metabolism ; Mice ; Humans ; *Prosthesis-Related Infections/immunology/microbiology ; Female ; Disease Models, Animal ; Metabolome ; Craniotomy ; Male ; Mice, Inbred C57BL ; Amino Acids/metabolism ; Leukocytes/immunology/metabolism ; Transcriptome ; Lipid Metabolism ; }, abstract = {Infection is a devastating post-surgical complication, often requiring additional procedures and prolonged antibiotic therapy. This is especially relevant for craniotomy and prosthetic joint infections (PJI), both of which are characterized by biofilm formation on the bone or implant surface, respectively, with S. aureus representing a primary cause. The local tissue microenvironment likely has profound effects on immune attributes that can influence treatment efficacy, which becomes critical to consider when developing therapeutics for biofilm infections. However, the extent to which distinct tissue niches influence immune function during biofilm development remains relatively unknown. To address this, we compare the metabolomic, transcriptomic, and functional attributes of leukocytes in mouse models of S. aureus craniotomy and PJI complemented with patient samples from both infection modalities, which reveals profound tissue niche-dependent differences in nucleic acid, amino acid, and lipid metabolism with links to immune modulation. These signatures are both spatially and temporally distinct, differing not only between infection sites but evolving over time within a single model. Collectively, this demonstrates that biofilms elicit unique immune and metabolic responses that are heavily influenced by the local tissue microenvironment, which will likely have important implications when designing therapeutic approaches targeting these infections.}, }
@article {pmid39419903, year = {2024}, author = {Cheraghi, N and Khoshnood, S and Sadeghifard, N and Khodaei, N and Asadollahi, P and Bastaminejad, S and Kouhsari, E and Omidi, N and Kalani, BS}, title = {Unveiling the impact of antibiotic stress on biofilm formation and expression of toxin-antitoxin system genes in Clostridium difficile clinical isolates.}, journal = {Molecular biology reports}, volume = {51}, number = {1}, pages = {1060}, pmid = {39419903}, issn = {1573-4978}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Clostridioides difficile/genetics/drug effects ; *Anti-Bacterial Agents/pharmacology ; *Toxin-Antitoxin Systems/genetics ; *Microbial Sensitivity Tests ; *Gene Expression Regulation, Bacterial/drug effects ; Humans ; Bacterial Toxins/genetics ; Bacterial Proteins/genetics/metabolism ; Vancomycin/pharmacology ; Metronidazole/pharmacology ; Clostridium Infections/microbiology/genetics ; }, abstract = {OBJECTIVES: The study investigates how antibiotics affect biofilm formation and toxin gene expression in Clostridium difficile, which is essential for its survival and persistence.<br><br>METHODS: The study confirmed 25 strains of C. difficile and assessed biofilm formation. The MIC of metronidazole and vancomycin was determined through agar dilution, and the impact of sub-MIC levels on biofilm formation and eradication was investigated. Additionally, Real-time PCR was used to analyze the expression levels of target genes related to antibiotic treatment.<br><br>RESULTS: We found that certain genes, such as the ImmA/IrrE system, were associated with increased biofilm formation in isolates. Sub-MIC antibiotic levels influenced gene expression related to biofilm activities, particularly emphasizing the importance of toxin-antitoxin systems. The results suggest that antibiotics at sub-MIC levels may play a signaling role in promoting biofilm formation and gene expression in C. difficile.<br><br>CONCLUSION: Our study suggests that toxin and antitoxin genes may impact C. difficile biofilm formation, while antibiotics could signal biofilm strengthening and gene expression increase.}, }
@article {pmid39419737, year = {2024}, author = {Gonçalves, FMC and de Almeida, EMFC and Hannig, C and Quinteiro, JP and Delbem, ACB and Cannon, ML and Danelon, M}, title = {Biofilm modulation and demineralization reduction after treatment with a new toothpaste formulation containing fluoride, casein phosphopeptide-amorphous calcium phosphate, and sodium trimetaphosphate: In situ study.}, journal = {Dental materials : official publication of the Academy of Dental Materials}, volume = {40}, number = {12}, pages = {2077-2084}, doi = {10.1016/j.dental.2024.09.018}, pmid = {39419737}, issn = {1879-0097}, mesh = {*Caseins/pharmacology ; *Biofilms/drug effects ; *Cross-Over Studies ; Humans ; Double-Blind Method ; *Fluorides/pharmacology ; *Polyphosphates/pharmacology/chemistry ; Animals ; Adult ; *Toothpastes/chemistry/pharmacology ; Cattle ; *Tooth Demineralization/prevention &amp; control ; Male ; Female ; Hardness ; Cariostatic Agents/pharmacology/chemistry ; Dental Enamel/drug effects ; Young Adult ; }, abstract = {OBJECTIVE: This in situ study aimed to evaluate a new toothpaste formulation containing fluoride (F), casein phosphopeptide amorphous calcium phosphate (CPP-ACP) and sodium trimetaphosphate (TMP) on the process of dental demineralization and biofilm composition.<br><br>METHODS: This crossover double-blind study consisted of five phases, in which 10 volunteers wore intraoral appliances containing four bovine enamel specimens. The cariogenic challenge was performed using 30&#xa0;% sucrose solution. Blocks were treated 3&#xa0;&#xd7;/day with the following toothpastes: 1) Placebo (No F-TMP-CPP-ACP), 2) 1100&#xa0;ppm F (1100F), 3) 1100F&#xa0;+&#xa0;3&#xa0;%TMP (1100F-TMP), 4) 1100F&#xa0;+&#xa0;10&#xa0;%CPP-ACP (1100F-CPP-ACP) and 5) 1100F-CPP-ACP-TMP. After 7 days, the percentage loss of surface hardness (%SH), integrated loss of subsurface hardness (&#x394;KHN), F, calcium (Ca) and phosphorus (P) concentration in the enamel was determined. The concentration of F, Ca, P and insoluble extracellular polysaccharide (EPS) in the biofilm were analyzed.<br><br>RESULTS: The addition of CPP-ACP-TMP to 1100F reduced %SH by 42&#xa0;% and 39&#xa0;% when compared to the 1100F and 1100F-CPP-ACP (p&#xa0;<&#xa0;0.001); in addition, to a reduction in lesion body (&#x394;KHN) by 36&#xa0;% for the same treatments. The treatment with 1100F-CPP-ACP-TMP led to a significant increase in the concentration of F, P and Ca in the enamel and biofilm, and reduced the concentration of EPS (p&#xa0;<&#xa0;0.001).<br><br>SIGNIFICANCE: Toothpaste formulation containing 1100F-CPP-ACP-TMP prevented the reduction of enamel hardness and significantly influenced the ionic biochemical composition and insoluble extracellular polysaccharide (EPS) in biofilm formed in situ. These results are promising and provide valuable insights for the design of further clinical trials.}, }
@article {pmid39419459, year = {2024}, author = {Awad, R and Marchand, S and Couet, W and Nasser, M and Buyck, JM and Tewes, F}, title = {Assessment of inhaled cationic antibiotics in an in vitro model of Pseudomonas aeruginosa lung biofilm.}, journal = {Microbial pathogenesis}, volume = {197}, number = {}, pages = {107020}, doi = {10.1016/j.micpath.2024.107020}, pmid = {39419459}, issn = {1096-1208}, mesh = {*Pseudomonas aeruginosa/drug effects/physiology ; *Biofilms/drug effects/growth &amp; development ; *Anti-Bacterial Agents/pharmacology ; *Tobramycin/pharmacology ; *Colistin/pharmacology ; *Microbial Sensitivity Tests ; *Alginates/pharmacology ; Humans ; Pseudomonas Infections/microbiology/drug therapy ; Administration, Inhalation ; Lung/microbiology ; Glucuronic Acid/pharmacology ; Culture Media/chemistry ; Hexuronic Acids/pharmacology ; Sputum/microbiology ; Models, Biological ; }, abstract = {OBJECTIVES: This study aimed to evaluate the efficacy of inhaled cationic antibiotics, including tobramycin (TOB) and colistin (CST), using an in vitro alginate bead model that simulates Pseudomonas aeruginosa lung biofilms.<br><br>METHODS: Bioluminescent P. aeruginosa were encapsulated within alginate beads and dispersed in either Mueller-Hinton broth (MHB) or artificial sputum medium (ASM). The impact of bead size and culture medium on TOB and CST efficacy was assessed by monitoring bioluminescence kinetics, followed by colony-forming unit (CFU/mL) measurements. Antibiotic efficacy was quantified using a Hill inhibitory model to analyze variations in CFU/mL in response to TOB and CST concentrations.<br><br>RESULTS: The TOB EC50 was found to be 8-fold higher when P. aeruginosa was encapsulated in larger beads (1200&#xa0;&#x3bc;m) compared to smaller beads (60&#xa0;&#x3bc;m). TOB efficacy further decreased twofold when larger beads were dispersed in ASM. In contrast, CST demonstrated superior efficacy, being four times more potent than TOB, with corresponding EC50 values of 20.5&#xa0;&#xb1;&#xa0;2.8 times MIC and 78.4&#xa0;&#xb1;&#xa0;10.2 times MIC, respectively. No change in MICs was observed for either antibiotic, even after exposing bacteria to 200 times the MIC.<br><br>CONCLUSIONS: This P. aeruginosa biofilm model highlights how alginate and mucus modulated the efficacy of TOB and CST, and suggested the superior efficacy of CST in eradicating pulmonary biofilms.}, }
@article {pmid39418672, year = {2025}, author = {Bahraminia, M and Cui, S and Zhang, Z and Semlali, A and Le Roux, &#xc9; and Giroux, KA and Lajoie, C and Béland, F and Rouabhia, M}, title = {Effect of cannabidiol (CBD), a cannabis plant derivative, against Candida albicans growth and biofilm formation.}, journal = {Canadian journal of microbiology}, volume = {71}, number = {}, pages = {1-13}, doi = {10.1139/cjm-2024-0034}, pmid = {39418672}, issn = {1480-3275}, mesh = {*Cannabidiol/pharmacology ; *Biofilms/drug effects/growth &amp; development ; *Candida albicans/drug effects/growth &amp; development ; *Antifungal Agents/pharmacology ; Cannabis/chemistry/growth &amp; development ; Hyphae/drug effects/growth &amp; development ; Microbial Sensitivity Tests ; }, abstract = {Cannabidiol (CBD) decreases the growth of C. albicans. CBD inhibits the yeast-to-hyphae transition. CBD reduces biofilm formation by C. albicans. CBD induces C. albicans death through necrosis.}, }
@article {pmid39417236, year = {2024}, author = {Ma, Y and Mao, Y and Kang, X and Zhang, B and Wang, J and Wang, G and Wang, G}, title = {Transcriptomic Analysis of the Effect of Glabridin on Biofilm Formation in Staphylococcus Aureus.}, journal = {Foodborne pathogens and disease}, volume = {}, number = {}, pages = {}, doi = {10.1089/fpd.2024.0038}, pmid = {39417236}, issn = {1556-7125}, abstract = {Staphylococcus aureus (S. aureus) is among the major skin infection-causing pathogens in animals and humans. Its ability to form biofilms has become a foremost cause of bacterial infections and the extensive spread of drug resistance, which poses a great difficulty in clinical treatment. Glabridin (Glb), an extract of licorice with antibacterial and anti-infective properties, has a partially understood biofilm-inhibitory mechanism. This study investigated the inhibitory and antibiofilm activities of subinhibitory concentrations of Glb against S. aureus. The crystal violet assay revealed that Glb significantly suppressed biofilm expression. Scanning electron microscopy observations unveiled that Glb reduced S. aureus adhesion and accumulation by disrupting the spatial structure of the biofilm. In vitro extracellular DNA (eDNA) inhibition assays demonstrated that Glb inhibited biofilm formation by S. aureus by suppressing eDNA secretion. In total, 184 differentially expressed genes were obtained through transcriptomic (RNA-seq) sequencing, of which 81 and 103 genes were upregulated and downregulated, respectively. Glb regulated the transcript levels of biofilm-related genes through the phosphatase transfer system, two-component regulatory system, and nitrogen metabolism. The qPCR analysis was performed to confirm whether Glb interfered with the expression of regulatory genes involved in S. aureus biofilm formation (SarA, ArlR, FnbA, ClfA, icaD, and icaR) as well as the virulence gene Hla. In conclusion, this study demonstrates that Glb has a significant inhibitory effect on biofilm activity and is expected to be a good antibiofilm drug.}, }
@article {pmid39415412, year = {2024}, author = {Basotra, SD and Kumari, Y and Vij, M and Tyagi, A and Sharma, D and Bhattacharyya, MS}, title = {Correction to "ASLdC3: A Derivative of Acidic Sophorolipid Disrupts Mitochondrial Function, Induces ROS Generation, and Inhibits Biofilm Formation in Candida albicans".}, journal = {ACS infectious diseases}, volume = {10}, number = {11}, pages = {4009}, doi = {10.1021/acsinfecdis.4c00753}, pmid = {39415412}, issn = {2373-8227}, }
@article {pmid39414638, year = {2024}, author = {Ghaleb, RN and Bhosale, HJ and Siddiqui, MM and Jadhav, SB and Mamdapure, SV and Shirure, NU and Shinde, SS and Mundhe, PP and Chame, AL and Dhonge, AR}, title = {2,4-Di-Tert-Butylphenol of Streptomyces luridiscabiei MMS-10 Inhibits Biofilm Forming Cariogenic Streptococcus mutans ULSP-2.}, journal = {Current microbiology}, volume = {81}, number = {12}, pages = {413}, pmid = {39414638}, issn = {1432-0991}, mesh = {*Phenols/pharmacokinetics/pharmacology ; *Anti-Bacterial Agents/pharmacology ; *Streptomyces/chemistry/classification/isolation &amp; purification ; *Biofilms/drug effects ; *Streptococcus mutans/drug effects ; Dental Caries/microbiology ; Drug Resistance, Bacterial/drug effects ; Microbial Sensitivity Tests ; Phylogeny ; }, abstract = {Dental caries is a common chronic infectious disease of the oral cavity that affects the overall oral health of the individual. Cariogenic bacteria have long been recognized for their role in developing chronic dental infections. Drug-resistant bacteria represent a global challenge to effective pathogen control in caries. The present study aimed to isolate and identify soil actinomycetes for their antibacterial and anti-biofilm activities against antibiotic-resistant and biofilm-forming cariogenic bacteria. Thirteen caries bacteria isolated from infected tooth samples were evaluated for antibiotic resistance and biofilm formation. The isolate ULSP-2 showed the highest antibiotic resistance score (0.714) and was found to be a strong biofilm producer when tested by congo red agar and microtiter plate assays. The bacterium was identified as Streptococcus mutans based on morphological, biochemical, and molecular characterization. The effect of ethyl acetate extracts from 20 soil actinomycetes on the growth and biofilm formation ability of S. mutans was evaluated. The MMS-10 extract strongly inhibited growth (18.5 ± 0.5 mm) and biofilm formation (56.46 ± 0.32%) of S. mutans at 100 µg/mL. The isolate MMS-10 was identified at the molecular level as Streptomyces luridiscabiei. Based on FTIR, NMR, and GC-MS analysis, the purified MMS-10 extract was characterized and identified as 2,4-Di-tert-butylphenol. The metabolite's physiological, physicochemical, and pharmacokinetic properties were analyzed using the Swiss ADME web server and found to satisfy the criteria of drug-likenessof a molecule. The study revealed the significance of soil actinomycetes in controlling growth and biofilm formation in cariogenic S. mutans.}, }
@article {pmid39414168, year = {2024}, author = {Li, M and Bae, S}, title = {Exploring the effects of polyethylene and polyester microplastics on biofilm formation, membrane Fouling, and microbial communities in Modified Ludzack-Ettinger-Reciprocation membrane bioreactors.}, journal = {Bioresource technology}, volume = {414}, number = {}, pages = {131636}, doi = {10.1016/j.biortech.2024.131636}, pmid = {39414168}, issn = {1873-2976}, mesh = {*Biofilms/drug effects ; *Bioreactors/microbiology ; *Membranes, Artificial ; *Polyethylene/chemistry ; *Polyesters/chemistry ; *Biofouling ; *Microplastics ; Nitrates/pharmacology ; Microbiota/drug effects ; Bacteria/drug effects ; Water Purification/methods ; Denitrification ; }, abstract = {Microplastics (MPs) inevitably enter wastewater treatment plants (WWTPs), yet their impacts remain poorly understood. This study investigates the effects of MPs on system performance and membrane fouling in a Modified Ludzack-Ettinger (MLE)-Reciprocation Membrane Bioreactor (rMBR), an energy-efficient alternative to conventional membrane bioreactors. Additionally, the study examines changes in microbial community induced by different types and shapes of MPs-polyethylene (PE) pellets and polyester (PES) fibers- as well as biofilm formation on MPs, using next-generation sequencing. Results revealed that transmembrane pressure (TMP) increased 2-3 times faster in the presence of PE pellets, while TMP remained stable during the PES stage, implying that MP type and shape could influence biofouling behaviors. Furthermore, enhanced nitrate removal was observed in the aerobic tank due to denitrifying biofilm formation on MPs. However, PES MPs reduced nitrate removal efficiency from 99.6 ± 0.3 % to 90.9 ± 7.9 % and decreased the relative abundance of denitrifying bacteria. Numerous taxa showed affinity to PE pellets, including some pathogens, e.g., Norcadia and Mycobacterium. Notably, an uncultured phylum Candidatus Saccharibacteria dominated in membrane biofilm and MPs, reaching up to 37 % relative abundance. This study is the first to explore how different types and shapes of MPs affect membrane bioreactor systems, particularly with respect to microbial community structure and biofilm formation. The findings offer new insights into the influence of MPs on wastewater treatment processes and highlight the significance of the uncultured phylumCandidatus Saccharibacteriain membrane fouling.}, }
@article {pmid39414110, year = {2024}, author = {Ren, M and Su, J and Bai, Y and Wang, Y and Hou, C and Zhang, Y}, title = {Simultaneous removal of nitrate, manganese, zinc, and bisphenol a by a biofilm reactor with β-CD modified corn stover biochar and PU sponges: Performance and microbial community response.}, journal = {Environmental research}, volume = {263}, number = {Pt 2}, pages = {120156}, doi = {10.1016/j.envres.2024.120156}, pmid = {39414110}, issn = {1096-0953}, mesh = {*Biofilms ; *Zea mays/chemistry ; *Phenols ; *Zinc ; *Charcoal/chemistry ; *Manganese ; *Bioreactors/microbiology ; *Benzhydryl Compounds ; *Nitrates ; *Polyurethanes/chemistry ; beta-Cyclodextrins/chemistry ; Water Pollutants, Chemical ; }, abstract = {In the present study, a biofilm reactor with manganese (Mn) redox cycling was established to remove nitrate (NO3[-]-N), bisphenol A (BPA), zinc (Zn(II)), and Mn(II) using β-cyclodextrin (β-CD) modified corn stover biochar (BC) and polyurethane sponges loaded with Cupriavidus sp. HY129 and Pantoea sp. MFG10. At C/N = 2.0, HRT = 6 h, Mn(II) = 10.0 mg L[-1], and BPA and Zn(II) concentrations = 1.0 mg L[-1], the removal efficiencies of NO3[-]-N, Zn(II), BPA, and Mn(II) were 81.5%, 86.5%, 87.9%, and 75.5%, respectively. The outcomes demonstrated the success that the addition of β-CD could accelerate electron transfer activity and the denitrification process. The remediation of BPA and Zn(II) was mainly through the adsorption of bioprecipitation generated by reactor operation. The bioreactor could preserve the stability of the biological community and the expression of pertinent functional genes under the coercion of BPA and Zn(II).}, }
@article {pmid39412570, year = {2024}, author = {Al-Seraih, A and Belguesmia, Y and Baah, J and Szunerits, S and Boukherroub, R and Drider, D}, title = {Correction: Enterocin B3A-B3B produced by LAB collected from infant faeces: potential utilization in the food industry for Listeria monocytogenes biofilm management.}, journal = {Antonie van Leeuwenhoek}, volume = {118}, number = {1}, pages = {20}, doi = {10.1007/s10482-024-02005-4}, pmid = {39412570}, issn = {1572-9699}, }
@article {pmid39412467, year = {2025}, author = {Pasaoglu Bozkurt, A and Demirci, M and Erdogan, P and Kayalar, E}, title = {Comparison of microbial adhesion and biofilm formation on different orthodontic aligners.}, journal = {American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics}, volume = {167}, number = {1}, pages = {47-62}, doi = {10.1016/j.ajodo.2024.08.010}, pmid = {39412467}, issn = {1097-6752}, mesh = {*Biofilms/growth &amp; development ; *Streptococcus mutans ; *Bacterial Adhesion ; *Lactobacillus acidophilus/physiology ; Humans ; }, abstract = {INTRODUCTION: This study aimed to compare and evaluate time-dependent biofilm formation and microbial adhesion on 6 different clear aligner systems: Invisalign (Align Technology, San Jose, Calif), Clarity (3M ESPE Maplewood, Minn), ClearCorrect (Institut Straumann AG, Basel, Switzerland), Smartee (Smartee Denti-Technology, Shanghai, China), Orthero (Orthero, Istanbul, Turkey) and Graphy (Graphy Inc, Seoul, South Korea).<br><br>METHODS: Streptococcus mutans (ATCC 25175) and Lactobacillus acidophilus (ATCC 4356) were used to evaluate the microbial adhesion and biofilm formation on orthodontic clear aligners at the 0, 24, 48, 72, 96, 120, 168, and 240 hours. Two-way repeated measures analysis of variance (Greenhouse-Geisser) test and post-hoc Bonferroni T2 tests were used for statistical evaluation. The statistical significance level was set at P&#xa0;<0.05.<br><br>RESULTS: It was found that more bacterial formation occurred on ClearCorrect than on Smartee at 120, 168, and 240 hours (P&#xa0;<0.05). It was observed more biofilm formation at 168 hours on Graphy than on Smartee (P&#xa0;<0.05). It was found that S mutans&#xa0;+ L acidophilus formed more biofilm at 120 and 168 hours on Graphy than on Invisalign (P&#xa0;<0.05).<br><br>CONCLUSIONS: Elevated biofilm formation across all materials carries substantial clinical implications. Orthodontists and patients should remain aware of the increased risk of microbial colonization with extended aligner usage.}, }
@article {pmid39412265, year = {2024}, author = {Shostak, MO and Cox, MA and Richards, N and Field, EK}, title = {Evaluation of biofilm assembly and microbial diversity on a freshwater, ferrous-hulled shipwreck.}, journal = {Applied and environmental microbiology}, volume = {90}, number = {11}, pages = {e0177024}, pmid = {39412265}, issn = {1098-5336}, mesh = {*Biofilms/growth &amp; development ; *Fresh Water/microbiology ; Corrosion ; *Ships ; *Bacteria/classification/genetics/isolation &amp; purification/metabolism ; Iron/metabolism ; Microbiota ; }, abstract = {UNLABELLED: Abandoned shipwrecks are sitting at the bottom of oceans, lakes, and rivers around the world. Over time, microbial-comprised biofilms can help protect wrecks against chemical corrosion or contribute to their deterioration through microbiologically influenced corrosion (MIC) by organisms including iron-oxidizing bacteria (FeOB) and sulfate-reducing bacteria (SRB). Assessing the community assembly of these biofilms will give us a better understanding of the role these microbes play in MIC and the factors that influence it. Here, we determine if microbial community composition differs across a shallow freshwater ferrous-hulled shipwreck environment. Results suggest that there was a statistically significant difference among the sample types indicating the wreck environments around Accomac influenced the community composition. This is consistent with previous observations within an estuarine, shallow-water wreck environment. Bacteroidota, Chloroflexota, and Cyanobacteriota were the primary taxa responsible for differences among these wreck environments. Interestingly, port-side biofilm communities were significantly different than those on the starboard side suggesting physical factors of the environment drove niche partitioning on each side of the wreck. Similarly, FeOB enrichments and known FeOB taxa were found across the entire wreck but were primarily found in samples associated with the port side of the wreck. Amplicon sequencing identified both known FeOB and SRB taxa with a higher proportion of FeOB than SRB. Overall, these results indicate that there is niche partitioning of the microbial communities as well as with corrosion-causing taxa within a shallow freshwater wreck site which may lead to variation in how microbes may contribute to the protection or deterioration of these ferrous-hulled wrecks.<br><br>IMPORTANCE: The overall structure, abundance, and diversity of microbial communities on shipwrecks have recently been studied in marine aquatic environments. While previous studies have looked at the microbial communities associated with shallow-water ferrous-hulled wrecks in marine environments, studies focusing on freshwater wreck systems are limited. The purpose of this study was to determine microbial community diversity and composition trends across the Accomac shipwreck environment. Furthermore, shipwrecks are colonized by corrosion-causing taxa, such as iron-oxidizing bacteria and sulfate-reducing bacteria which have been shown to influence the biocorrosion of ferrous-hulled structures. Identification of various microbes in biofilms, as well as corrosion-causing microbes, can help researchers identify the role they play in aquatic ecosystem development and persistence as well as artificial reef integrity. Understanding how microbes assemble on wrecks will provide insight into preservation strategies to prevent deterioration of these wrecks over time, as well as limiting biocorrosion of similar structures.}, }
@article {pmid39412231, year = {2024}, author = {Quiñones-Vico, MI and Andrades-Amate, M and Fernández-González, A and Ubago-Rodríguez, A and Moll, K and Norrby-Teglund, A and Svensson, M and Gutiérrez-Fernández, J and Arias-Santiago, S}, title = {Antibiotic biocompatibility assay and anti-biofilm strategies for Pseudomonas aeruginosa infection in bioengineered artificial skin substitutes.}, journal = {The Journal of antimicrobial chemotherapy}, volume = {79}, number = {12}, pages = {3313-3322}, doi = {10.1093/jac/dkae365}, pmid = {39412231}, issn = {1460-2091}, support = {//Ministry of Science, Innovation and Universities of Spain/ ; PIGE-0242-2019//Ministry of Health and Families of the Andalusian Regional Government/ ; PI17/02083//Carlos III Health Institute/ ; 10007//European Molecular Biology Organization/ ; 2022-01202//Swedish Research Council/ ; FoUI-961229//Region Stockholm/ ; FoUI-975603//Center for Innovative Medicine/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Skin, Artificial ; *Anti-Bacterial Agents/pharmacology ; *Pseudomonas aeruginosa/drug effects ; *Pseudomonas Infections/drug therapy/microbiology ; Humans ; Cell Survival/drug effects ; Microbial Sensitivity Tests ; }, abstract = {OBJECTIVES: Bioengineered artificial skin substitutes (BASS) are an advanced therapy for treating extensively burned patients. Pseudomonas aeruginosa (P. aeruginosa) infections represent a major challenge in these patients as formation of biofilms impede wound healing and perpetuate a chronic inflammatory state. Here we assessed antibiotics (alone or in combination) with respect to cytotoxicity, as well as antimicrobial efficacy in P. aeruginosa biofilm formed on infection of BASS.<br><br>METHODS: Cell viability, structure and functionality were evaluated using microscopy and trans-epidermal water loss analyses, respectively. BASS were established and infected for 24&#x2005;h to allow P. aeruginosa biofilm formation, after which two antimicrobial approaches, treatment and prevention, were tested. In the latter, antibiotics were added to BASS before infection. The antimicrobial effect was determined using real-time calorimetry.<br><br>RESULTS: In dose-response experiments, 1.25&#x2005;mg/mL amikacin, 0.02&#x2005;mg/mL ciprofloxacin, 0.051&#x2005;mg/mL colistin, 1&#x2005;mg/mL meropenem and colistin in combination with either amikacin, ciprofloxacin and meropenem did not affect BASS' viability, structure and functionality. All antibiotics, except colistin, showed effective antimicrobial activity at these non-cytotoxic concentrations. For concentrations below the highest non-cytotoxic ones, successive treatments resulted in higher bacterial metabolic rates. Only the combinations managed to eradicate the infection with repeated treatments. With respect to prevention of infection, all antibiotics at the highest non-cytotoxic concentrations and the combinations were effective. This preventive capacity was maintained for at least 5&#x2005;days.<br><br>CONCLUSION: The findings highlight the potential for developing BASS with antimicrobial properties that can prevent infections during wound healing in burn patients.}, }
@article {pmid39410520, year = {2024}, author = {Mayer, P and Smith, AC and Hurlow, J and Morrow, BR and Bohn, GA and Bowler, PG}, title = {Assessing Biofilm at the Bedside: Exploring Reliable Accessible Biofilm Detection Methods.}, journal = {Diagnostics (Basel, Switzerland)}, volume = {14}, number = {19}, pages = {}, pmid = {39410520}, issn = {2075-4418}, support = {N/A//MolecuLight Inc/ ; }, abstract = {INTRODUCTION: Biofilm is linked through a variety of mechanisms to the pathogenesis of chronic wounds. However, accurate biofilm detection is challenging, demanding highly specialized and technically complex methods rendering it unapplicable for most clinical settings. This study evaluated promising methods of bedside biofilm localization, fluorescence imaging of wound bacterial loads, and biofilm blotting by comparing their performance against validation scanning electron microscopy (SEM).<br><br>METHODS: In this clinical trial, 40 chronic hard-to-heal wounds underwent the following assessments: (1) clinical signs of biofilm (CSB), (2) biofilm blotting, (3) fluorescence imaging for localizing bacterial loads, wound scraping taken for (4) SEM to confirm matrix encased bacteria (biofilm), and (5) PCR (Polymerase Chain Reaction) and NGS (Next Generation Sequencing) to determine absolute bacterial load and species present. We used a combination of SEM and PCR microbiology to calculate the diagnostic accuracy measures of the CSB, biofilm blotting assay, and fluorescence imaging.<br><br>RESULTS: Study data demonstrate that 62.5% of wounds were identified as biofilm-positive based on SEM and microbiological assessment. By employing this method to determine the gold truth, and thus calculate accuracy measures for all methods, fluorescence imaging demonstrated superior sensitivity (84%) and accuracy (63%) compared to CSB (sensitivity 44% and accuracy 43%) and biofilm blotting (sensitivity 24% and accuracy 40%). Biofilm blotting exhibited the highest specificity (64%), albeit with lower sensitivity and accuracy. Using SEM alone as the validation method slightly altered the results, but all trends held constant.<br><br>DISCUSSION: This trial provides the first comparative assessment of bedside methods for wound biofilm detection. We report the diagnostic accuracy measures of these more feasibly implementable methods versus laboratory-based SEM. Fluorescence imaging showed the greatest number of true positives (highest sensitivity), which is clinically relevant and provides assurance that no pathogenic bacteria will be missed. It effectively alerted regions of biofilm at the point-of-care with greater accuracy than standard clinical assessment (CSB) or biofilm blotting paper, providing actionable information that will likely translate into enhanced therapeutic approaches and better patient outcomes.}, }
@article {pmid39410102, year = {2024}, author = {Serrano, S and Ferreira, MV and Alves-Barroco, C and Morais, S and Barreto-Crespo, MT and Tenreiro, R and Semedo-Lemsaddek, T}, title = {Beyond Harmful: Exploring Biofilm Formation by Enterococci Isolated from Portuguese Traditional Cheeses.}, journal = {Foods (Basel, Switzerland)}, volume = {13}, number = {19}, pages = {}, pmid = {39410102}, issn = {2304-8158}, support = {PTDC/OCE-ETA/1785/2020//Funda&#xe7;&#xe3;o para a Ci&#xea;ncia e Tecnologia/ ; UIDB/00276/2020//Funda&#xe7;&#xe3;o para a Ci&#xea;ncia e Tecnologia/ ; LA/P/0059/2020-AL4ANIMALS//Funda&#xe7;&#xe3;o para a Ci&#xea;ncia e Tecnologia/ ; UI/BD/153073/2022//Funda&#xe7;&#xe3;o para a Ci&#xea;ncia e Tecnologia/ ; }, abstract = {This study investigated the biofilm-forming capabilities of Enterococcus isolates from Portuguese traditional cheeses with protected designation of origin (PDO) status, specifically Azeitão and Nisa. Given the absence of added starter cultures in the cheesemaking process, the characteristics of these cheeses are intrinsically linked to the autochthonous microbiota present in the raw materials and the production environment. Our findings demonstrate that all isolates possess biofilm production abilities, which are crucial for their colonization and persistence within cheese factories, thereby maintaining factory-specific microbial heritage. Through an integrated analysis utilizing principal component analysis (PCA), a direct correlation between biofilm formation and cell viability was established. Notably, these results underscore the adaptive capacity of enterococci to survive environmental fluctuations and their role in the unique characteristics of Portuguese traditional cheeses. Overall, this research enhances our understanding of the microbial dynamics in cheese production and highlights the importance of enterococci in preserving cheese quality and heritage.}, }
@article {pmid39409551, year = {2024}, author = {Pandey, C and Christensen, A and Jensen, MNPB and Rechnagel, ER and Gram, K and Roitsch, T}, title = {Stimulation of Arabidopsis thaliana Seed Germination at Suboptimal Temperatures through Biopriming with Biofilm-Forming PGPR Pseudomonas putida KT2440.}, journal = {Plants (Basel, Switzerland)}, volume = {13}, number = {19}, pages = {}, pmid = {39409551}, issn = {2223-7747}, support = {LM2023048//Novo Nordisk Foundation and Ministry of Education for Youth and Sports of CR within the CzeCOS program/ ; }, abstract = {This study investigated the germination response to temperature of seeds of nine Arabidopsis thaliana ecotypes. They are characterized by a similar temperature dependency of seed germination, and 10 °C and 29 °C were found to be suboptimal low and high temperatures for all nine ecotypes, even though they originated from regions with diverse climates. We tested the potential of four PGPR strains from the genera Pseudomonas and Bacillus to stimulate seed germination in the two ecotypes under these suboptimal conditions. Biopriming of seeds with only the biofilm-forming strain Pseudomonas putida KT2440 significantly increased the germination of Cape Verde Islands (Cvi-0) seeds at 10 °C. However, biopriming did not significantly improve the germination of seeds of the widely utilized ecotype Columbia 0 (Col-0) at any of the two tested temperatures. To functionally investigate the role of KT2440's biofilm formation in the stimulation of seed germination, we used mutants with compromised biofilm-forming abilities. These bacterial mutants had a reduced ability to stimulate the germination of Cvi-0 seeds compared to wild-type KT2440, highlighting the importance of biofilm formation in promoting germination. These findings highlight the potential of PGPR-based biopriming for enhancing seed germination at low temperatures.}, }
@article {pmid39409056, year = {2024}, author = {D'Angelo, C and Faggiano, S and Imbimbo, P and Viale, E and Casillo, A and Bettati, S and Olimpo, D and Tutino, ML and Monti, DM and Corsaro, MM and Ronda, L and Parrilli, E}, title = {Pentadecanoic Acid-Releasing PDMS: Towards a New Material to Prevent S. epidermidis Biofilm Formation.}, journal = {International journal of molecular sciences}, volume = {25}, number = {19}, pages = {}, pmid = {39409056}, issn = {1422-0067}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Staphylococcus epidermidis/drug effects/physiology ; Humans ; *Dimethylpolysiloxanes/chemistry/pharmacology ; *Fatty Acids/chemistry/pharmacology ; Anti-Bacterial Agents/pharmacology/chemistry ; Keratinocytes/drug effects ; }, abstract = {Microbial biofilm formation on medical devices paves the way for device-associated infections. Staphylococcus epidermidis is one of the most common strains involved in such infections as it is able to colonize numerous devices, such as intravenous catheters, prosthetic joints, and heart valves. We previously reported the antibiofilm activity against S. epidermidis of pentadecanoic acid (PDA) deposited by drop-casting on the silicon-based polymer poly(dimethyl)siloxane (PDMS). This material exerted an antibiofilm activity by releasing PDA; however, a toxic effect on bacterial cells was observed, which could potentially favor the emergence of resistant strains. To develop a PDA-functionalized material for medical use and overcome the problem of toxicity, we produced PDA-doped PDMS by either spray-coating or PDA incorporation during PDMS polymerization. Furthermore, we created a strategy to assess the kinetics of PDA release using ADIFAB, a very sensitive free fatty acids fluorescent probe. Spray-coating resulted in the most promising strategy as the concentration of released PDA was in the range 0.8-1.5 μM over 21 days, ensuring long-term effectiveness of the antibiofilm molecule. Moreover, the new coated material resulted biocompatible when tested on immortalized human keratinocytes. Our results indicate that PDA spray-coated PDMS is a promising material for the production of medical devices endowed with antibiofilm activity.}, }
@article {pmid39409032, year = {2024}, author = {Kornsombut, N and Takenaka, S and Manuschai, J and Sotozono, M and Nagata, R and Ida, T and Sato, R and Saito, R and Takahashi, R and Sato, D and Noiri, Y}, title = {Effects of Tooth Desensitizers on Streptococcus mutans Biofilm Formation Using a Modified Robbins Device Flow Cell System.}, journal = {International journal of molecular sciences}, volume = {25}, number = {19}, pages = {}, pmid = {39409032}, issn = {1422-0067}, support = {24K02763//Japan Society for the Promotion of Science/ ; 24K22229//Japan Society for the Promotion of Science/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Streptococcus mutans/drug effects/physiology ; Humans ; Dentin/microbiology ; Dentin Desensitizing Agents/pharmacology/chemistry ; }, abstract = {This study aimed to assess the antibiofilm effects of dentin desensitizers using a modified Robbins device flow cell system. The test desensitizers were Saforide, Caredyne Shield, and Clinpro White Varnish. Standardized dentin specimens were prepared from human single-rooted premolars, treated with one of the materials, and mounted on the modified Robbins device flow cell system. Streptococcus mutans biofilms were developed for 24 h at 37 °C under anaerobic conditions. Scanning electron microscopy, fluorescence confocal laser scanning microscopy, viable and total cell counts, acid production, and gene expression analyses were performed. A wavelength-dispersive X-ray spectroscopy electron probe microanalyzer was used to analyze the ion incorporations. Clinpro White Varnish showed the greatest inhibition, suggesting its suppression of bacterial adherence and transcription of genes related to biofilm formation. Saforide reduced only the number of viable bacteria, but other results showed no significant difference. The antibiofilm effects of Caredyne Shield were limited. The uptake of ions released from a material into dentin varies depending on the element. Clinpro White Varnish is effective for the short-term treatment of tooth sensitivity due to dentin demineralization. It prioritizes remineralization by supplying calcium and fluoride ions while resisting biofilm formation.}, }
@article {pmid39407838, year = {2024}, author = {Giordano, V and Giannoudis, PV}, title = {Biofilm Formation, Antibiotic Resistance, and Infection (BARI): The Triangle of Death.}, journal = {Journal of clinical medicine}, volume = {13}, number = {19}, pages = {}, pmid = {39407838}, issn = {2077-0383}, abstract = {Fracture-related infection (FRI) is a devastating event, directly affecting fracture healing, impairing patient function, prolonging treatment, and increasing healthcare costs. Time plays a decisive role in prognosis, as biofilm maturation leads to the development of antibiotic resistance, potentially contributing to infection chronicity and increasing morbidity and mortality. Research exploring the association between biofilm maturation and antibiotic resistance in orthopaedics primarily addresses aspects related to quality of life and physical function; however, little exists on life-threatening conditions and mortality. Understanding the intrinsic relationship between biofilm maturation, bacterial resistance, and mortality is critical in all fields of medicine. In the herein narrative review, we summarize recent evidence regarding biofilm formation, antibiotic resistance, and infection chronicity (BARI), the three basic components of the "triangle of death" of FRI, and its implications. Preoperative, perioperative, and postoperative prevention strategies to avoid the "triangle of death" of FRI are presented and discussed. Additionally, the importance of the orthopaedic trauma surgeon in understanding new tools to combat infections related to orthopaedic devices is highlighted.}, }
@article {pmid39407465, year = {2024}, author = {El-Sawy, ER and Abdel-Aziz, MS and Abdelmegeed, H and Kirsch, G}, title = {Coumarins: Quorum Sensing and Biofilm Formation Inhibition.}, journal = {Molecules (Basel, Switzerland)}, volume = {29}, number = {19}, pages = {}, pmid = {39407465}, issn = {1420-3049}, mesh = {*Coumarins/pharmacology/chemistry ; *Quorum Sensing/drug effects ; *Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; Humans ; Bacteria/drug effects ; }, abstract = {Quorum sensing (QS) is a bacterial cell-to-cell communication mechanism that plays an essential role in bacterial pathogenesis. QS governs bacterial behavior and controls biofilm formation, which in turn contributes to antibiotic resistance. Therefore, identifying and synthesizing novel compounds to overcome QS and inhibit biofilm formation are essential. Coumarins are important plant-derived natural products with wide-ranging bioactivities and extensive applications, including antibacterial, antifungal, anticoagulant, antioxidant, anticancer, and anti-inflammatory properties. Additionally, coumarins are capable of QS rewiring and biofilm formation inhibition, leading to higher susceptibility to antimicrobial agents and less antibiotic resistance. Therefore, in this review, we aim to provide an overview of QS and biofilm formation. This review also discusses the role of natural and synthesized coumarins in controlling QS, inhibiting biofilm formation, and inducing synergy in antibiotic-coumarin combinations. Hence, this review emphasizes the potential of coumarin compounds to act as antibacterial agents and demonstrates their ability to alleviate antibiotic resistance.}, }
@article {pmid39403724, year = {2024}, author = {Choi, W and Lee, H and Wang, Q and Bang, YJ and Choi, SH}, title = {Discovery of a Small-Molecule Inhibitor Targeting the Biofilm Regulator BrpT in Vibrio vulnificus.}, journal = {Journal of microbiology and biotechnology}, volume = {34}, number = {11}, pages = {2201-2210}, pmid = {39403724}, issn = {1738-8872}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Vibrio vulnificus/drug effects/genetics ; *Anti-Bacterial Agents/pharmacology ; *Bacterial Proteins/genetics/metabolism ; *Gene Expression Regulation, Bacterial/drug effects ; Humans ; High-Throughput Screening Assays ; Transcription Factors/genetics/metabolism/antagonists &amp; inhibitors ; Drug Discovery ; Small Molecule Libraries/pharmacology ; Microbial Sensitivity Tests ; Escherichia coli/drug effects/genetics ; Regulon ; }, abstract = {Vibrio vulnificus, an opportunistic human pathogen, employs biofilm formation as a key survival and virulence mechanism. BrpT, a transcriptional regulator, is essential for V. vulnificus biofilm development by regulating the expression of biofilm-related genes. In this study, we aimed to identify a small molecule inhibitor of BrpT to combat V. vulnificus biofilm formation. High-throughput screening of 7,251 compounds using an Escherichia coli reporter strain carrying the arabinose-inducible brpT gene and a BrpT-activated promoter fused to the luxCDABE operon identified a hit compound, BTI (BrpT Inhibitor). BTI potently inhibited BrpT activity in V. vulnificus (EC50 of 6.48 μM) without affecting bacterial growth or host cell viability. Treatment with BTI significantly reduced the expression of the BrpT regulon and impaired biofilm formation and colony rugosity in V. vulnificus, thus increasing its susceptibility to antibiotics. In vitro biochemical analyses revealed that BTI directly binds to BrpT and inhibits its transcriptional regulatory activity. The identification of BTI as a specific inhibitor of BrpT that effectively diminishes V. vulnificus biofilm formation provides a promising foundation for the development of novel anti-biofilm strategies, with the potential to address the growing challenge of antibiotic resistance and improve the treatment of biofilm-associated infections.}, }
@article {pmid39402785, year = {2024}, author = {Tran, HH and Jaruchotiratanasakul, N and Xiang, Z and Pandey, NK and Oh, MJ and Liu, Y and Ren, Z and Babeer, A and Zdilla, MJ and Cormode, DP and Karabucak, B and Lee, D and Steager, EB and Koo, H}, title = {Nanozyme-Shelled Microcapsules for Targeting Biofilm Infections in Confined Spaces.}, journal = {Advanced healthcare materials}, volume = {}, number = {}, pages = {e2402306}, doi = {10.1002/adhm.202402306}, pmid = {39402785}, issn = {2192-2659}, support = {R01 DE031491/DE/NIDCR NIH HHS/United States ; R56 DE029985/DE/NIDCR NIH HHS/United States ; }, abstract = {Bacterial infections in irregular and branched confinements pose significant therapeutic challenges. Despite their high antimicrobial efficacy, enzyme-mimicking nanoparticles (nanozymes) face difficulties in achieving localized catalysis at distant infection sites within confined spaces. Incorporating nanozymes into microrobots enables the delivery of catalytic agents to hard-to-reach areas, but poor nanoparticle dispersibility and distribution during fabrication hinder their catalytic performance. To address these challenges, a nanozyme-shelled microrobotic platform is introduced using magnetic microcapsules with collective and adaptive mobility for automated navigation and localized catalysis within complex confinements. Using double emulsions produced from microfluidics as templates, iron oxide and silica nanoparticles are assembled into 100-µm microcapsules, which self-organize into multi-unit, millimeter-size assemblies under rotating magnetic fields. These microcapsules exhibit high peroxidase-like activity, efficiently catalyzing hydrogen peroxide to generate reactive oxygen species (ROS). Notably, microcapsule assemblies display remarkable collective navigation within arched and branched confinements, reaching the targeted apical regions of the tooth canal with high accuracy. Furthermore, these nanozyme-shelled microrobots perform rapid catalysis in situ and effectively kill biofilms on contact via ROS generation, enabling localized antibiofilm action. This study demonstrates a facile method of integrating nanozymes onto a versatile microrobotic platform to address current needs for targeted therapeutic catalysis in complex and confined microenvironments.}, }
@article {pmid39402397, year = {2024}, author = {Ragupathi, H and Pushparaj, MM and Gopi, SM and Govindarajan, DK and Kandaswamy, K}, title = {Biofilm matrix: a multifaceted layer of biomolecules and a defensive barrier against antimicrobials.}, journal = {Archives of microbiology}, volume = {206}, number = {11}, pages = {432}, pmid = {39402397}, issn = {1432-072X}, support = {SRG/2019/000094//Science and Engineering Research Board/ ; }, mesh = {*Biofilms/drug effects ; *Bacteria/drug effects/metabolism/genetics ; *Bacteriophages/physiology ; Extracellular Polymeric Substance Matrix/metabolism ; Anti-Bacterial Agents/pharmacology ; Anti-Infective Agents/pharmacology ; }, abstract = {Bacterial cells often exist in the form of sessile aggregates known as biofilms, which are polymicrobial in nature and can produce slimy Extracellular Polymeric Substances (EPS). EPS is often referred to as a biofilm matrix and is a heterogeneous mixture of various biomolecules such as polysaccharides, proteins, and extracellular DNA/RNA (eDNA/RNA). In addition, bacteriophage (phage) was also found to be an integral component of the matrix and can serve as a protective barrier. In recent years, the roles of proteins, polysaccharides, and phages in the virulence of biofilms have been well studied. However, a mechanistic understanding of the release of such biomolecules and their interactions with antimicrobials requires a thorough review. Therefore, this article critically reviews the various mechanisms of release of matrix polymers. In addition, this article also provides a contemporary understanding of interactions between various biomolecules to protect biofilms against antimicrobials. In summary, this article will provide a thorough understanding of the functions of various biofilm matrix molecules.}, }
@article {pmid39402087, year = {2024}, author = {Abou Elez, RMM and Zahra, EMF and Gharieb, RMA and Mohamed, MEM and Samir, M and Saad, AM and Merwad, AMA}, title = {Resistance patterns, virulence determinants, and biofilm genes of multidrug-resistant Pseudomonas aeruginosa isolated from fish and fish handlers.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {24063}, pmid = {39402087}, issn = {2045-2322}, mesh = {*Pseudomonas aeruginosa/genetics/pathogenicity/drug effects/isolation &amp; purification ; *Biofilms/growth &amp; development/drug effects ; Animals ; *Drug Resistance, Multiple, Bacterial/genetics ; Humans ; *Virulence Factors/genetics ; *Fishes/microbiology ; *Anti-Bacterial Agents/pharmacology ; Egypt ; Pseudomonas Infections/microbiology/veterinary ; Virulence/genetics ; Microbial Sensitivity Tests ; Fish Diseases/microbiology ; Cross-Sectional Studies ; Gentamicins/pharmacology ; }, abstract = {Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic bacterium that is widely distributed in aquatic environments and causes major economic losses in fish and public health hazards.This study aimed to identify the occurrence of P. aeruginosa in samples collected from fish and fish handlers, and to investigate the antimicrobial susceptibility, virulence determinants, and biofilm genes of P. aeruginosa isolates. A total of 276 samples were cross-sectionally collected from Nile tilapia (53), Golden grey mullet (52), Mediterranean horse mackerel (50), Striped red mullet (71), and fish handlers (50) at five different retail fish markets in Damietta Governorate, Egypt. Pseudomonas species (spp.) were biochemically identified in 57.9% of the total examined samples. Peudomonas aeruginosa were the most prevalent species isolated from the fish and human samples via PCR technique. Peudomonas aeruginosa isolates exhibited full resistance (100%) to tobramycin (TOB), gentamicin (CN), and colistin (CL), with a high level of susceptibility (88.5%) to imipenem (IPM) using the disk diffusion method. Most P. aeruginosa isolates (84.6%) exhibited drug resistance, with 61.5% were multidrug resistance (MDR) and 23.1% were extensive drug resistance (XDR). Most isolates had at least four virulence-associated genes (lasB, toxA, exoU, and oprL) and three biofilm genes (psIA, peIA, and lasR) by using uniplex PCR. The lasI, and rhlR Quorum Sensing (QS) genes were identified in 84.6% and 61.5% in the examined P. aeruginosa isolates, respectively. The highest mortality rate in Nile tilapia experimentally infected with P. aeruginosa isolate encoding most of virulent genes. Multivariate analyses revealed high heterogeneity among the examined isolates. This study revealed the emergence of virulent and drug resistant P. aeruginosa isolates in fish, poses high risks to consumers and food. Thus, strict hygienic measures should be considered when catching, handling, and storing fish, in addition to the routine application of antimicrobial susceptibility testing.}, }
@article {pmid39402074, year = {2024}, author = {Ingino, P and Eraky, H and Zhang, C and Hitchcock, AP and Obst, M}, title = {Soft X-ray spectromicroscopic proof of a reversible oxidation/reduction of microbial biofilm structures using a novel microfluidic in situ electrochemical device.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {24009}, pmid = {39402074}, issn = {2045-2322}, mesh = {*Biofilms/growth &amp; development ; *Oxidation-Reduction ; *Electrochemical Techniques/methods ; X-Rays ; Lab-On-A-Chip Devices ; Bacteria ; }, abstract = {In situ electrochemistry on micron and submicron-sized individual particles and thin layers is a valuable, emerging tool for process understanding and optimization in a variety of scientific and technological fields such as material science, process technology, analytical chemistry, and environmental sciences. Electrochemical characterization and manipulation coupled with soft X-ray spectromicroscopy helps identify, quantify, and optimize processes in complex systems such as those with high heterogeneity in the spatial and/or temporal domain. Here we present a novel platform optimized for in situ electrochemistry with variable liquid electrolyte flow in soft X-ray scanning transmission X-ray microscopes (STXM). With four channels for fluid control and a modular design, it is suited for a wealth of experimental conditions. We demonstrate its capabilities by proving the reversible oxidation and reduction of individual microbial biofilm structures formed by microaerophilic Fe(II)-oxidizing bacteria, also known as twisted stalks. We show spectromicroscopically the heterogeneity of the redox activity on the submicron scale. Examples are also provided of electrochemical modification of liquid electrolyte species (Fe(II) and Fe(III) cyanides), and in situ studies of electrodeposited copper nanoparticles as CO2 reduction electrocatalysts under reaction conditions.}, }
@article {pmid39398375, year = {2024}, author = {Del Pozo, ML and Aguanell, A and García-Junceda, E and Revuelta, J}, title = {Lysozyme-Responsive Hydrogels of Chitosan-Streptomycin Conjugates for the On-Demand Release of Biofilm-Dispersing Enzymes for the Efficient Eradication of Oral Biofilms.}, journal = {Chemistry of materials : a publication of the American Chemical Society}, volume = {36}, number = {19}, pages = {9860-9873}, pmid = {39398375}, issn = {0897-4756}, abstract = {Hydrogels with controlled degradation and sustained antibiofilm activity are promising biomaterials for the treatment of oral infections such as periodontitis or caries. In this article, an in situ forming chitosan-streptomycin hydrogel is developed that can target established bacterial biofilms in response to lysozyme, an enzyme that is overexpressed in saliva during oral infections. When the new hydrogel is applied to simulated oral biofilms, the overexpressed lysozyme degrades the hydrogel and releases chitosan-streptomycin oligosaccharides that can eradicate the biofilm. This work has shown that the coupling of chitosan and streptomycin can have a synergistic effect and that the new hydrogel based on chitosan-streptomycin conjugate can effectively combat biofilms of E. coli, S. aureus, and P. aeruginosa formed in vitro achieving a significant reduction in the biomass of the biofilm and a substantial reduction in the population of viable bacteria in established biofilms. Finally, the CS-Str hydrogel loaded with biofilm-disrupting enzymes, in particular, DNase I and/or DspB, showed a significantly increased ability to reduce the biofilm biomass of P. aeruginosa and S. aureus (by over 84% and up to 92%, respectively), resulting in a drastic reduction in cell viability, which fell below 4% for P. aeruginosa and below 5% for S. aureus.}, }
@article {pmid39397932, year = {2024}, author = {Rashtchi, P and van der Linden, E and Habibi, M and Abee, T}, title = {Biofilm formation of Lactiplantibacillus plantarum food isolates under flow and resistance to disinfectant agents.}, journal = {Heliyon}, volume = {10}, number = {19}, pages = {e38502}, pmid = {39397932}, issn = {2405-8440}, abstract = {Bacterial biofilms formed in food processing environments can be resilient against cleaning and disinfection causing recontamination and spoilage of foods. We investigated the biofilm formation of six Lactiplantibacillus plantarum food spoilage isolates (FBR1-FBR6) using WCFS1 as a reference strain, and examined the impact of benzalkonium chloride (BKC) and peracetic acid (PAA) on planktonic and biofilm cells formed under static and dynamic flow conditions. We used a custom-designed setup composed of a 48-well plate with 0.8 ml culture volumes. We quantified biofilm formation under static and dynamic flow conditions with a flow rate of 3.2 ml/h using plate counting, Crystal Violet (CV) staining, and fluorescence staining techniques. Our findings revealed significant differences in biofilm formation and disinfectant resistance among studied strains and cell types. We observed that flow promoted biofilm formation in some strains and increased the number of culturable cells within biofilms in all strains. Furthermore, biofilm cells demonstrated higher resistance to disinfectants in comparison to planktonic cells for certain strains. Interestingly, cells from dispersed under flow biofilms show higher resistance to disinfectants than cells from static biofilms. The results indicate the importance of flow conditions in influencing L. plantarum food isolates biofilm formation and disinfection resistance, which may have implications for product contamination and spoilage risks.}, }
@article {pmid39396077, year = {2024}, author = {Lennert, KJ and Borsodi, AK and Anda, D and Krett, G and Kós, PB and Engloner, AI}, title = {The effect of urbanization on planktonic and biofilm bacterial communities in different water bodies of the Danube River in Hungary.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {23881}, pmid = {39396077}, issn = {2045-2322}, support = {RRF 2.3.1 21 2022 00008//Sz&#xe9;chenyi Terv Plusz program/ ; RRF 2.3.1 21 2022 00008//Sz&#xe9;chenyi Terv Plusz program/ ; RRF 2.3.1 21 2022 00008//Sz&#xe9;chenyi Terv Plusz program/ ; 2018-1.2.1-NKP-2018-00011//National Excellence Project NKFIH/ ; 2018-1.2.1-NKP-2018-00011//National Excellence Project NKFIH/ ; }, mesh = {*Biofilms/growth &amp; development ; Hungary ; *Urbanization ; *Rivers/microbiology ; *Plankton/genetics ; *Bacteria/genetics/classification/isolation &amp; purification ; *RNA, Ribosomal, 16S/genetics ; Water Microbiology ; Ecosystem ; Biodiversity ; Humans ; Lakes/microbiology ; }, abstract = {Freshwaters play an essential role in providing ecosystem services worldwide, however, the water quality of different water bodies is strongly influenced by human activities such as urbanization, industry and agriculture. In this study, water and biofilm samples were collected from the main channel of the Danube River upstream and downstream of a metropolitan, from a regulated side arm within an urbanized area, and from two differently separated oxbow lakes located in nature conservation areas. The taxonomic diversity of bacterial communities was revealed by 16S rRNA gene-based amplicon sequencing using Illumina MiSeq platform. The results showed that all samples were dominated by phyla Pseudomonadota, Actinobacteriota and Bacteroidota. The bacterial community structures, however, clearly differentiated according to planktonic and epilithic or epiphytic habitats, as well as by riverine body types (main channel, side arm, oxbow lakes). The taxonomic diversity of biofilm communities was higher than that of planktonic ones in all studied habitats. Human impacts were mainly reflected in the slowly changing biofilm composition compared to the planktonic ones. Genera with pollution tolerance and/or degradation potential, such as Acinetobacter, Pseudomonas and Shewanella were mainly detected in biofilm communities of the highly urbanized section of the river side arm.}, }
@article {pmid39395965, year = {2024}, author = {Villanueva-Cotrina, F and Bejar, V and Guevara, J and Cajamarca, I and Medina, C and Mujica, L and Lescano, AG}, title = {Biofilm formation and increased mortality among cancer patients with candidemia in a Peruvian reference center.}, journal = {BMC infectious diseases}, volume = {24}, number = {1}, pages = {1145}, pmid = {39395965}, issn = {1471-2334}, mesh = {Humans ; *Biofilms/growth &amp; development ; *Candidemia/mortality/microbiology/drug therapy ; Male ; Female ; Retrospective Studies ; Middle Aged ; Peru/epidemiology ; *Neoplasms/complications/mortality/microbiology ; Aged ; *Antifungal Agents/therapeutic use ; *Candida/isolation &amp; purification/physiology/drug effects ; Adult ; }, abstract = {BACKGROUND: Candidemia is an invasive mycosis with an increasing global incidence and high mortality rates in cancer patients. The production of biofilms by some strains of Candida constitutes a mechanism that limits the action of antifungal agents; however, there is limited and conflicting evidence about its role in the risk of death. This study aimed to determine whether biofilm formation is associated with mortality in cancer patients with candidemia.<br><br>METHODS: This retrospective cohort study included patients treated at Peru's oncologic reference center between June 2015 and October 2017. Data were collected by monitoring patients for 30 days from the diagnosis of candidemia until the date of death or hospital discharge. Statistical analyses evaluated the association between biofilm production determined by XTT reduction and mortality, adjusting for demographic, clinical, and microbiological factors assessed by the hospital routinary activities. Survival analysis and bivariate and multivariate Cox regression were used, estimating the hazard ratio (HR) as a measure of association with a significance level of p&#x2009;<&#x2009;0.05.<br><br>RESULTS: A total of 140 patients with candidemia were included in the study. The high mortality observed on the first day of post-diagnosis follow-up (81.0%) among 21 patients who were not treated with either antifungal or antimicrobial drugs led to stratification of the analyses according to whether they received treatment. In untreated patients, there was a mortality gradient in patients infected with non-biofilm-forming strains vs. low/medium and high-level biofilm-forming strains (25.0%, 66.7% and 82.3%, respectively, p&#x2009;=&#x2009;0.049). In treated patients, a high level of biofilm formation was associated with increased mortality (HR, 3.92; 95% p&#x2009;=&#x2009;0.022), and this association persisted after adjusting for age, comorbidities, and hospital emergency admission (HR, 6.59; CI: 1.87-23.24, p&#x2009;=&#x2009;0.003).<br><br>CONCLUSIONS: The association between candidemia with in vitro biofilm formation and an increased risk of death consistently observed both in patients with and without treatment, provides another level of evidence for a possible causal association. The presence of comorbidities and the origin of the hospital emergency, which reflect the fragile clinical condition of the patients, and increasing age above 15 years were associated with a higher risk of death.}, }
@article {pmid39395748, year = {2024}, author = {Krishnasamy, N and Ramadoss, R and Vemuri, S and Sujai, GNS}, title = {Optimizing Desmostachya bipinnata-derived platinum nanoparticles for enhanced antibacterial and biofilm reduction.}, journal = {Microbial pathogenesis}, volume = {196}, number = {}, pages = {107004}, doi = {10.1016/j.micpath.2024.107004}, pmid = {39395748}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Platinum/chemistry/pharmacology ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Metal Nanoparticles/chemistry ; *Staphylococcus aureus/drug effects ; *Escherichia coli/drug effects ; *Microbial Sensitivity Tests ; *Plant Extracts/pharmacology/chemistry ; Mouthwashes/pharmacology/chemistry ; Particle Size ; Spectroscopy, Fourier Transform Infrared ; Green Chemistry Technology ; }, abstract = {This study presents the green synthesis and comprehensive characterization of platinum nanoparticles (PtNPs) using Desmostachya bipinnata (Db) extract, incorporated into two innovative mouthwash formulations (MW1 and MW2). UV-Vis spectroscopy confirmed the successful synthesis of PtNPs, with distinct absorption peaks between 250 and 600 nm. Fourier-transform infrared (FTIR) spectroscopy identified hydroxyl and carbonyl functional groups, critical for the bioreduction and stabilization of PtNPs. High-resolution transmission electron microscopy (HR-TEM) revealed uniformly dispersed, spherical nanoparticles with a size range of 10-20 nm, while dynamic light scattering (DLS) confirmed a hydrodynamic diameter of 10-30 nm and a low polydispersity index (PDI) of 0.238, indicating excellent stability. Both formulations exhibited robust antimicrobial, antibiofilm, and anti-plaque properties, with MW2 showing superior efficacy, particularly against Staphylococcus aureus and Escherichia coli, as well as a notable 70 % reduction in biofilm formation and a 60 % plaque reduction within 2 h of treatment. The study underscores the potential of Desmostachya bipinnata-derived PtNPs as a promising alternative to conventional mouthwash, offering enhanced antimicrobial efficacy, biofilm disruption, and plaque prevention, alongside excellent stability and biocompatibility for oral healthcare applications.}, }
@article {pmid39395744, year = {2024}, author = {Gopinath, V and Mitra, K and Chadha, A and Doble, M}, title = {Disrupting Mycobacterium smegmatis biofilm using enzyme-immobilized rifampicin loaded silk fibroin nanoparticles for dual anti-bacterial and anti-biofilm action.}, journal = {Microbial pathogenesis}, volume = {196}, number = {}, pages = {106999}, doi = {10.1016/j.micpath.2024.106999}, pmid = {39395744}, issn = {1096-1208}, mesh = {*Biofilms/drug effects ; *Nanoparticles/chemistry ; *Rifampin/pharmacology ; *Fibroins/chemistry/pharmacology ; *Mycobacterium smegmatis/drug effects ; *Enzymes, Immobilized/chemistry/pharmacology ; *Anti-Bacterial Agents/pharmacology/chemistry ; 6-Phytase/pharmacology/metabolism/chemistry ; beta-Glucosidase/metabolism/chemistry ; Microbial Sensitivity Tests ; Glucose Oxidase/pharmacology/metabolism/chemistry ; Extracellular Polymeric Substance Matrix/chemistry/drug effects/metabolism ; alpha-Amylases/metabolism/pharmacology/antagonists &amp; inhibitors ; Hydrophobic and Hydrophilic Interactions ; }, abstract = {Biofilm formation is a major challenge in the treatment of tuberculosis, leading to poor treatment outcomes and latent infections. The complex and dense extracellular polymeric substances (EPS) of the biofilm provides safe harbour for bacterium enabling persistence against anti-TB antibiotics. In this study, we demonstrated that rifampicin-encapsulated silk fibroin nanoparticles immobilized with antibiofilm enzymes can disrupt the Mycobacterium smegmatis biofilm and facilitate the anti-bacterial action of Rifampicin (RIF). The EPS of M.smegmatis biofilm predominantly comprised of lipids (48.8 ± 1.32 %) and carbohydrates (34.8 ± 4.70 %), similar to tuberculosis biofilms. Pre-formed biofilm eradication screening revealed that hydrolytic enzymes such as β-Glucosidase, Glucose oxidase, ɑ-Amylase, Acylase, and Phytase can exhibit biofilm eradication of M.smegmatis biofilms. The enzyme-mediated biofilm disruption was associated with a decrease in hydrophobicity of biofilm surfaces. Treatment with β-glucosidase and Phytase demonstrated a putative biofilm eradication by reducing the total carbohydrates and lipid composition without causing any significant bactericidal activity. Further, Phytase (250 μg/ml) and β-Glucosidase (112.5 ± 17.6 μg/ml) conjugated rifampicin-loaded silk fibroin nanoparticles (R-SFNs) exhibited an enhanced anti-bacterial activity against pre-formed M.smegmatis biofilms, compared to free rifampicin (32.5±7 μg/ml). Notably, treatment with β-glucosidase, Phytase and ɑ-amylase immobilized SFNs decreased the biofilm thickness by ∼98.84 % at 6h, compared to control. Thus, the study highlights that coupling anti-mycobacterial drugs with biofilm-eradicating enzymes such as amylase, phytase or β-glucosidase can be a potential strategy to improve the TB therapeutic outcomes.}, }
@article {pmid39395451, year = {2025}, author = {Werneburg, GT and Hettel, D and Goldman, HB and Vasavada, SP and Miller, AW}, title = {Indwelling Urological Device Biofilm Composition and Characteristics in the Presence and Absence of Infection.}, journal = {Urology}, volume = {196}, number = {}, pages = {82-89}, doi = {10.1016/j.urology.2024.10.021}, pmid = {39395451}, issn = {1527-9995}, mesh = {*Biofilms ; Humans ; Male ; *Prosthesis-Related Infections/microbiology ; Penile Prosthesis/microbiology ; Urinary Sphincter, Artificial/microbiology ; Stents/microbiology/adverse effects ; Middle Aged ; Catheters, Indwelling/microbiology/adverse effects ; Female ; Aged ; Adult ; }, abstract = {OBJECTIVE: To characterize microbial biofilms associated with different device types used in the urological field including ureteral stents, sacral neuromodulation (SNM) devices, penile prostheses, and artificial urinary sphincters (AUS).<br><br>MATERIALS AND METHODS: Data from 4 studies, each reporting biofilm composition of a particular device type, were pooled and included for inter-device analysis. Studies recruited adults scheduled for ureteral stent, SNM, IPP, or AUS removal/revision. Device (n&#xa0;=&#xa0;115) biofilms and controls were analyzed with multi-omics approaches, and compositions were compared across device types and clinical factors.<br><br>RESULTS: Microbiota present on each device type was distinct from that of perineal, rectal, or urine flora (P&#xa0;<.01). Biofilm microbial counts (P&#xa0;<.001) and diversity (P&#xa0;=&#xa0;.024) differed by device type. Ureteral stents had greater microbial counts than other device types (P&#xa0;<.001). Staphylococcus, Pseudomonas, Lactobacillus, Ureaplasma were commonly detected across devices. Device biofilms harbored a greater proportion of Proteobacteria phylum, and the rectal, perineal, and urine flora harbored a greater proportion of Firmicutes. Unique microbe-metabolite interaction networks were identified in presence and absence of infection. Antibiotic-resistance genes including sul2 (sulfonamide resistance) and rpoB (rifampin resistance) were detected in biofilms across device types. Biofilm reconstitution in vitro differed by device type from which strains were isolated.<br><br>CONCLUSION: Ureteral stents, sacral neuromodulation devices, penile prostheses, and artificial urinary sphincters harbored unique microbial and metabolite profiles that differed from those of skin, urine, and rectal flora. The findings of this study set the groundwork for investigation of novel strategies to reduce device-associated infection risk within and outside urology.}, }
@article {pmid39394228, year = {2024}, author = {Sato, Y and Hatayama, N and Suzuki, Y and Yugeta, N and Yoshino, Y}, title = {Staphylococcus pseudintermedius ST2660 isolated from a cat has strong biofilm-forming ability and increases biofilm formation at cat's normal body temperature.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {23820}, pmid = {39394228}, issn = {2045-2322}, support = {21K08516//Japan Society for the Promotion of Science/ ; 24K11641//Japan Society for the Promotion of Science/ ; 22-72//ACRO Incubation Grants from Teikyo University/ ; 23-93//ACRO Incubation Grants from Teikyo University/ ; }, mesh = {Cats ; *Biofilms/drug effects/growth &amp; development ; Animals ; *Staphylococcus/drug effects/isolation &amp; purification/genetics/physiology ; *Anti-Bacterial Agents/pharmacology ; *Staphylococcal Infections/microbiology/veterinary/drug therapy ; Body Temperature/drug effects ; Cat Diseases/microbiology ; Microbial Sensitivity Tests ; Fluoroquinolones/pharmacology ; }, abstract = {Staphylococcus pseudintermedius has been isolated from dogs, cats, and horses and is also known as an emergent zoonotic agent. We administered orbifloxacin, a fluoroquinolone, to treat bacterial infections of cutaneous wounds caused by excessive grooming of the skin in contact with the subcutaneous port of the subcutaneous ureteral bypass (SUB) system in a cat. However, after 80 days of treatment, a severe abscess was observed in the wound and fluoroquinolone-resistant S. pseudintermedius was isolated from the abscess. The isolate was identified as a novel sequence type (ST) 2660 and contained genes for leukocidins (lukS and lukF), exfoliative toxin (siet), and biofilm regulation (icaA and icaD). The isolate was resistant to macrolide, lincosamide, fluoroquinolone, and tetracycline classes. In addition, the isolate had strong biofilm-forming ability which significantly increased with culturing at 39 °C compared with that at 37 °C, suggesting that the isolate prefers a cats' body temperature as the optimal biofilm growth condition. Notably, the biofilms were increased in the presence of doxycycline with culturing at 39 °C. This study is the first report in Japan on the new sequence type of S. pseudintermedius isolated from a companion animal and clarifies the distinctive virulence of S. pseudintermedius.}, }
@article {pmid39393651, year = {2024}, author = {Peng, X and Zhang, D and Yuan, J and Yang, H and Li, M and Zhang, H and Niu, H and Zhu, C and Chen, Y and Zhao, C and Guo, T and Wang, Z and Liu, D and Ying, H}, title = {Engineering bacterium for biofilm formation and L-lysine production in continuous fermentation.}, journal = {Bioresource technology}, volume = {414}, number = {}, pages = {131567}, doi = {10.1016/j.biortech.2024.131567}, pmid = {39393651}, issn = {1873-2976}, mesh = {*Biofilms ; *Lysine/metabolism ; *Corynebacterium glutamicum/metabolism/genetics ; *Fermentation ; *Bioreactors/microbiology ; Genetic Engineering/methods ; }, abstract = {Microbial biofilms provide advantages in fermentation processes. However, Corynebacterium glutamicum (C. glutamicum) usually exhibits relatively poor biofilm formation compared to other industrial strains. To develop a biofilm-enhanced fermentation process for C. glutamicum, seven genes potentially related to biofilm formation in C. glutamicum were systematically investigated, which include ppk2B, glgC, virB11, cslA, NCgl2909, NCgl0350 and exeR. Deletion of the NCgl0350, NCgl2909 genes and heterologous expression of the cslA gene were found to increase biofilm amounts by 16.9%, 21.2% and 135%, respectively, compared to the wild-type strain. Meanwhile, the production of L-lysine by engineered strains was assessed in biofilm-based continuous fermentation. The most notable result was observed for the cslA-expressing strain, which produced an average of 26.1% higher L-lysine compared with that of wild-type strain in 6-L bioreactors. In conclusion, this study offers valuable insights into the biofilm formation in C. glutamicum and its application in continuous fermentation processes.}, }
@article {pmid39393342, year = {2024}, author = {Chowdhry, M and Dipane, MV and Duncan, ST and Pena, D and Stavrakis, A and McPherson, EJ}, title = {Next generation sequencing identifies an increased diversity of microbes in post lavage specimens in infected TKA using a biofilm disrupting irrigant.}, journal = {The Knee}, volume = {51}, number = {}, pages = {231-239}, doi = {10.1016/j.knee.2024.09.010}, pmid = {39393342}, issn = {1873-5800}, mesh = {Humans ; *Arthroplasty, Replacement, Knee ; *Prosthesis-Related Infections/microbiology/drug therapy/diagnosis ; *Biofilms ; *Therapeutic Irrigation ; Prospective Studies ; *High-Throughput Nucleotide Sequencing ; Male ; Female ; Aged ; Middle Aged ; Microbiota ; Synovial Fluid/microbiology ; Aged, 80 and over ; }, abstract = {BACKGROUND: Periprosthetic joint infection (PJI) is a devastating complication of joint arthroplasty. In chronic PJI, a biofilm envelops the surface of implants, which contains microbiota within an extra-microbial polymeric matrix (EMPM). Microbial identification is paramount for effective treatment. In this study, we use a multi-modal, EMPM disrupting, neoadjuvant irrigant and compare the microbiota detected pre-lavage to post-lavage by two techniques: culture and Next Generation Sequencing (NGS). We suspect more organisms to be identified after applying an EMPM disrupting irrigant.<br><br>METHODS: A multicenter, prospective study was conducted on 38 patients with known Total Knee Arthroplasty PJI. At initial arthrotomy, synovial fluid was obtained and analyzed for quantitative cultures and microbial NGS. Joint was then irrigated with Bactisure Lavage followed by Normal Saline. Post-lavage samples were similarly obtained and analyzed.<br><br>RESULTS: In pre-lavage samples for cultures, 55.3% of samples were positive, identifying 11 unique organisms. In post-lavage samples for cultures, 13.2% of samples were positive, identifying 5 unique organisms. In pre-lavage samples for NGS, 79% were DNA signal positive, identifying 126 unique organisms. In post-lavage samples for NGS, 74% of samples were DNA signal positive, identifying 177 unique organisms. Moreover, 135/177 of these organisms were not identified pre-lavage.<br><br>CONCLUSION: In this pre-to-post irrigant study, culture showed a decrease in the number of identifiable organisms post-lavage. In contrast NGS revealed an increase in the number of identifiable organisms post-lavage. Furthermore, NGS identified 135 additional organisms, not detected pre-lavage. This suggests an increased diversity of microbes may exist within EMPM, which are not cultivable.}, }
@article {pmid39393325, year = {2024}, author = {Yang, C and Huang, B and Lin, J and Yang, Q and Guo, Y and Liu, D and Sun, B}, title = {Isolation and screening of high biofilm producing lactic acid bacteria, and exploration of its effects on the microbial hazard in corn straw silage.}, journal = {Journal of hazardous materials}, volume = {480}, number = {}, pages = {136009}, doi = {10.1016/j.jhazmat.2024.136009}, pmid = {39393325}, issn = {1873-3336}, mesh = {*Biofilms ; *Zea mays/microbiology ; *Silage/microbiology ; Lactic Acid/metabolism ; Fermentation ; Lactobacillales/metabolism/genetics/isolation &amp; purification ; Lactobacillus plantarum/metabolism/genetics ; }, abstract = {Silage is a well-established method for preserving feed. However, the preparation process still poses several potential microbial hazards. Lactic acid bacteria exhibiting a biofilm phenotype are considered the most advanced 'fourth-generation probiotics' due to their significant potential in enhancing fermentation quality. In this study, a strain of high-biofilm-producing lactic acid bacteria (HBP-LAB) was successfully isolated from silage samples using the crystal violet method and designated as Lactiplantibacillus plantarum S23Y. This strain was subsequently used as an inoculant in corn straw for experimental purposes. The results indicated that it effectively reduced dry matter loss caused by microorganisms, thereby enhancing the retention of dry matter in silage. Following aerobic exposure, this strain was able to maintain the population of Lactobacillus and the concentration of lactic acid, which significantly decreased the likelihood of yeast-induced aerobic spoilage and improved the aerobic stability of the silage. However, it is important to note that this HBP-LAB did not have a significant impact on antibiotic resistance genes (ARGs) or mobile genetic elements (MGEs) in the silage. In conclusion, using S23Y as a representative strain, we have demonstrated that HBP-LAB can enhance the fermentation quality of silage to a certain extent and mitigate the detrimental effects of microorganisms. The findings of this study provide valuable insights for the application of lactic acid bacteria with a biofilm phenotype in silage fermentation.}, }
@article {pmid39392011, year = {2024}, author = {Javanmard, Z and Pourhajibagher, M and Bahador, A}, title = {Advancing Anti-Biofilm Strategies: Innovations to Combat Biofilm-Related Challenges and Enhance Efficacy.}, journal = {Journal of basic microbiology}, volume = {64}, number = {12}, pages = {e2400271}, doi = {10.1002/jobm.202400271}, pmid = {39392011}, issn = {1521-4028}, mesh = {Humans ; Anti-Bacterial Agents/pharmacology ; Anti-Infective Agents/pharmacology ; Bacteria/drug effects/growth &amp; development/radiation effects ; *Biofilms/drug effects/growth &amp; development/radiation effects ; Nanotechnology/methods ; Photochemotherapy/methods ; *Quorum Sensing/drug effects/radiation effects ; }, abstract = {Biofilms are complex communities of microorganisms that can cause significant challenges in various settings, including industrial processes, environmental systems, and human health. The protective nature of biofilms makes them resistant to traditional anti-biofilm strategies, such as chemical agents, mechanical interventions, and surface modifications. To address the limitations of conventional anti-biofilm methods, researchers have explored emerging strategies that encompass the use of natural compounds, nanotechnology-based methods, quorum-sensing inhibition, enzymatic degradation, and antimicrobial photodynamic/sonodynamic therapy. There is an increasing focus on combining multiple anti-biofilm strategies to combat resistance and enhance effectiveness. Researchers are continuously investigating the mechanisms of biofilm formation and developing innovative approaches to overcome the limitations of conventional anti-biofilm methods. These efforts aim to improve the management of biofilms and prevent infections while preserving the environment. This study provides a comprehensive overview of the latest advancements in anti-biofilm strategies. Given the dynamic nature of this field, exploring new approaches is essential to stimulate further research and development initiatives. The effective management of biofilms is crucial for maintaining the health of industrial processes, environmental systems, and human populations.}, }
@article {pmid39391921, year = {2024}, author = {Samoilova, Z and Smirnova, G and Sutormina, L and Oktyabrsky, O}, title = {Modulating effects of fodder grasses extracts on antibiotic sensitivity and biofilm production in avian pathogenic Escherichia coli strains.}, journal = {Biofouling}, volume = {40}, number = {10}, pages = {816-830}, doi = {10.1080/08927014.2024.2414222}, pmid = {39391921}, issn = {1029-2454}, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology ; *Escherichia coli/drug effects/physiology ; *Plant Extracts/pharmacology ; Animals ; *Microbial Sensitivity Tests ; Ciprofloxacin/pharmacology ; Poaceae/microbiology ; Escherichia coli Infections/drug therapy/microbiology/veterinary ; Cefotaxime/pharmacology ; Streptomycin/pharmacology ; }, abstract = {Extracts of certain fodder grasses may be viewed as powerful agents against infections induced by avian pathogenic Escherichia coli strains. Here we demonstrated ability of Galega orientalis and Rhaponticum carthamoides extracts, alone or in combination with antibiotics, to inhibit growth, viability and biofilm formation in avian pathogenic Escherichia coli strains with different sensitivity to antibiotics and non-pathogenic laboratory strain E. coli BW25113 as well as its mutant derivatives. Modulation of motility and production of extracellular structures in the presence of the extracts correlated with their anti-biofilm effects. Interestingly, an increase in antibacterial action of kanamycin, streptomycin, ciprofloxacin, and cefotaxime on both biofilms and planktonic cultures of the studied strains was observed in the presence of the extracts, including antibiotic resistant APEC strain #45. The extracts alone showed weak prooxidant activity which could contribute to modification of redox-sensitive sites of various regulatory circuits, resulting to synergetic effects in combination with antibiotics.}, }
@article {pmid39386371, year = {2024}, author = {Salazar, M and Shahbazi Nia, S and German, NA and Awosile, B and Sabiu, S and Calle, A}, title = {Exploring diflunisal as a synergistic agent against Staphylococcus aureus biofilm formation.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1399996}, pmid = {39386371}, issn = {1664-302X}, abstract = {Staphylococcus aureus is a bacterial pathogen of considerable significance in public health, capable of inducing a diverse range of infectious diseases. One of the most notorious mechanisms used by S. aureus to survive and colonize the site of infection is its ability to form biofilms. Diflunisal, a non-steroidal anti-inflammatory drug (NSAID), is a known inhibitor of the Agr system in S. aureus, which is key in regulating biofilm formation. This study evaluated the effect of broad-spectrum antibiotics in combination with diflunisal on S. aureus biofilm density. Eight antibiotics were tested independently at different concentrations and in combination with diflunisal to assess their effect on S. aureus biofilm formation. When using the antibiotics alone and with diflunisal, a significant control effect on biofilm formation was observed (p < 0.05), irrespective of diflunisal presence, but did not achieve a complete biofilm growth inhibition. Over time, diflunisal influenced biofilm formation; however, such an effect was correlated with antibiotic concentration and exposure time. With amikacin treatments, biofilm density increased with extended exposure time. In the case of imipenem, doripenem, levofloxacin, and ciprofloxacin, lower doses and absence of diflunisal showed higher control over biofilm growth with longer exposure. However, in all cases, diflunisal did not significantly affect the treatment effect on biofilm formation. In the absence of antibiotics, diflunisal significantly reduced biofilm formation by 53.12% (p < 0.05). This study suggests that diflunisal could be a potential treatment to control S. aureus biofilms, but it does not enhance biofilm inhibition when combined with antibiotics.}, }
@article {pmid39385119, year = {2024}, author = {Rizkinata, D and Waturangi, DE and Yulandi, A}, title = {Synergistic action of bacteriophage and metabolites of Pseudomonas fluorescens JB3B and Streptomyces thermocarboxydus 18PM against Enterotoxigenic Escherichia coli and Bacillus cereus and their biofilm.}, journal = {BMC microbiology}, volume = {24}, number = {1}, pages = {398}, pmid = {39385119}, issn = {1471-2180}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Bacillus cereus/drug effects/virology ; *Pseudomonas fluorescens/virology/drug effects ; *Streptomyces/virology/physiology ; *Enterotoxigenic Escherichia coli/drug effects/physiology ; *Bacteriophages/physiology ; Anti-Bacterial Agents/pharmacology ; Food Microbiology ; }, abstract = {BACKGROUND: Foodborne disease and food spoilage are the prime public health issue and food security round the globe. Significant disease outbreaks mostly linked to the existence of pathogenic bacteria that extremely challenging due to the persistence of biofilm-forming. Proteins and bacterial metabolites have been shown to have good antibacterial activity and effectively removal bacterial biofilm. Recently, bacteriophage and their encoded lytic proteins such as lysin have attracted attention as potential alternative agent to control undesirable pathogens in human body infection, increasing food safety as advance preservations and medical treatment such as phage therapy. For these reasons, the efficacy of bacteriophage and their potential in combination with bacterial metabolites from Phyllosphere and Actinomycetes bacteria (Pseudomonas fluorescens JB3B and Streptomyces thermocarboxydus 18PM crude extracts) was the aim of this present study.<br><br>RESULTS: In this study, bacteriophage BC-VP (1.28&#x2009;&#xb1;&#x2009;0.29&#x2009;&#xd7;&#x2009;10[11] PFU/ml) and ETEC-phage-TG (8.9&#x2009;&#xb1;&#x2009;2.19&#x2009;&#xd7;&#x2009;10[8] PFU/ml) isolated from artificial lake water from previous study showed potential activity to control Bacillus cereus (BC) and Enterotoxigenic Escherichia coli (ETEC) population. The combination of BC-VP with metabolite (P. fluorescens JB3B and S. thermocarboxydus 18PM) which were known from previous study had antibiofilm activities were able to inhibit (86.1%; 83.3%) and destruct (41%; 45.5%) biofilm formation of B. cereus respectively. Likewise, the synergy of bacteriophage ETEC-phage-TG with the same crude extract also showed promising activity against biofilm of ETEC with percentage of inhibition (81.9%; 76.4%) and percentage of destruction (54.1%; 44.4%). Application in various food, combination of BC-VP and bacterial metabolite extract (P. fluorescens JB3B; S. thermocarboxydus 18PM) were able to reduce Bacillus cereus population in mashed potato (99.6%; 99.4%) at cold temperature (4&#xa0;&#xb0;C) and (68.9%; 56.6%) at room temperature (28&#xa0;&#xb0;C), boiled pasta (99.5%; 99.4%) and (84.7%; 75.7%), also soymilk (96.9%; 96.7%) and (42.4%; 39.4%) respectively. Likewise, combination of ETEC-phage-TG and bacterial metabolite (P. fluorescens JB3B; S. thermocarboxydus 18PM) potentially reduced ETEC population after two different temperatures (4&#xa0;&#xb0;C and 28&#xa0;&#xb0;C) incubation in bean sprouts (TFTC; TFTC) and (47.5%; 49.1%), chicken meat (TFTC; TFTC) and (58.1%; 54%), also minced beef (99.5%; 99.4%) and (41.1%; 28%). GC-MS determination performed, oxalic acid, phenol, phenylethyl alcohol, N-hexadecanoic acid, and pyrolol[1,2-a]pyrazine-1,4-dione, hexadro-3-92-methylpropyl was the most active compound in P. fluorescens JB3B. 2,4-Di-tert-butylphenol, phenyl acetic acid, N-Hexadecanoic acid, pyrolol[1,2-a]pyrazine-1,4-dione, hexadro-3-92-methylpropyl, and Bis(2-ethylhexyl) phthalate was most active compound in the S. thermocarboxydus 18PM isolates.<br><br>CONCLUSIONS: The combination of isolated bacteriophages and bacterial metabolite showed promising results to be used as biocontrol candidate to overcome biofilm formed by foodborne and food spoilage bacteria using their ability to produce antibiofilm compounds and lytic activity. In addition, this combination also potentially reduces the use or replace the drawbacks of common application such as antibiotic treatment.}, }
@article {pmid39384943, year = {2024}, author = {Du, X and Li, P and Fan, C and Tian, J and Lin, Y and Xie, J and Cheng, J and Fu, Y and Jiang, D and Yuan, M and Yu, X and Tsuda, K and Li, B}, title = {Holliday junction resolvase RuvC targets biofilm eDNA and confers plant resistance to vascular pathogens.}, journal = {Nature plants}, volume = {10}, number = {11}, pages = {1710-1723}, pmid = {39384943}, issn = {2055-0278}, support = {32272556//National Natural Science Foundation of China (National Science Foundation of China)/ ; }, mesh = {*Biofilms ; *Solanum lycopersicum/microbiology/genetics/physiology ; *Plant Diseases/microbiology/immunology ; *Xanthomonas/physiology ; *Ralstonia solanacearum/physiology ; Holliday Junction Resolvases/metabolism/genetics ; Disease Resistance/genetics ; Bacterial Proteins/metabolism/genetics ; Oryza/microbiology/genetics/physiology ; Plant Proteins/genetics/metabolism ; }, abstract = {A biofilm lifestyle is critical for bacterial pathogens to colonize and protect themselves from host immunity and antimicrobial chemicals in plants and animals. The formation and regulation mechanisms of phytobacterial biofilm are still obscure. Here we found that the protein Ralstonia solanacearum resistance to ultraviolet C (RuvC) is highly abundant in biofilm and positively regulates pathogenicity by controlling systemic movement in tomato xylem. RuvC protein accumulates at the later stage of biofilm development and specifically targets Holliday junction (HJ)-like structures to disrupt the biofilm extracellular DNA (eDNA) lattice, thus facilitating biofilm dispersal. Recombinant RuvC protein can resolve extracellular HJ to prevent bacterial biofilm formation. Heterologous expression of R. solanacearum or Xanthomonas oryzae pv. oryzae RuvC with plant secretion signal in tomato or rice confers resistance to bacterial wilt or bacterial blight disease, respectively. Plant chloroplast-localized HJ resolvase monokaryotic chloroplast 1 (MOC1), which shares structural similarity with bacterial RuvC, shows a strong inhibitory effect on bacterial biofilm formation. Relocalization of SlMOC1 to apoplast in tomato roots leads to increased resistance to bacterial wilt. Our novel finding reveals a critical pathogenesis mechanism of R. solanacearum and provides an efficient biotechnology strategy to improve plant resistance to bacterial vascular disease.}, }
@article {pmid39384811, year = {2024}, author = {Devanga Ragupathi, NK and Muthuirulandi Sethuvel, DP and Ganesan, A and Murugan, D and Baskaran, A and Wannigama, DL and Monk, PN and Karunakaran, E and Veeraraghavan, B}, title = {Evaluation of mrkD, pgaC and wcaJ as biomarkers for rapid identification of K. pneumoniae biofilm infections from endotracheal aspirates and bronchoalveolar lavage.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {23572}, pmid = {39384811}, issn = {2045-2322}, support = {10065043//QR GCRF , UKRI/ ; GCRFNGR5\1293//Academy of Medical Sciences, UK/ ; }, mesh = {*Biofilms/growth &amp; development ; *Klebsiella pneumoniae/genetics/isolation &amp; purification ; Humans ; *Klebsiella Infections/microbiology/diagnosis ; *Biomarkers ; Bronchoalveolar Lavage Fluid/microbiology ; Bacterial Proteins/genetics ; }, abstract = {Klebsiella pneumoniae has been identified as one of the most important opportunistic pathogens responsible for nosocomial infections. Antibiotic resistance and the ability to form biofilms are the two main factors involved in the persistence of infections. Conventional detection methods involve culture isolation and identification followed by biofilm assay that takes 48-72 h. Timely detection of biofilm-forming resistant pathogens is essential to appropriately treat the infection with the right dose and combinations. The present study focuses on evaluating an RT-PCR panel using mrkD, pgaC, and wcaJ genes to screen for biofilm-forming K. pneumoniae from ETA/BAL specimens. The assay accurately identified K. pneumoniae harboring samples with a limit of detection of 1 ng/µl total RNA. Representative culture-negative-PCR-positive samples were subjected to metagenomics which identified K. pneumoniae reads in these samples confirming the specificity of RT-PCR. mrkD and pgaC act as K. pneumoniae specific identification whereas wcaJ acts as a negative marker for biofilm-forming K. pneumoniae. In addition, RT-PCR results correlated well with the phenotypic biofilm-forming assay. This RT-PCR assay is the first of its kind for rapid identification of biofilm-forming K. pneumoniae. The result of this study highlights that the rapid detection of K. pneumoniae biofilms based on the RT-PCR results coupled with clinical conditions would be appropriate to treat emerging infections or to prevent re-infections in clinical settings.}, }
@article {pmid39384621, year = {2024}, author = {Pal, S and Chatterjee, N and Sinha Roy, S and Chattopadhyay, B and Acharya, K and Datta, S and Dhar, P}, title = {Valorization of oil refinery by-products: production of sophorolipids utilizing fatty acid distillates and their potential antibacterial, anti-biofilm, and antifungal activities.}, journal = {World journal of microbiology &amp; biotechnology}, volume = {40}, number = {11}, pages = {344}, pmid = {39384621}, issn = {1573-0972}, support = {1626/(NET-DEC2018)//University Grants Commission/ ; }, mesh = {*Biofilms/drug effects ; *Antifungal Agents/pharmacology/metabolism ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology/biosynthesis ; *Plant Oils/pharmacology/metabolism/chemistry ; *Fatty Acids ; Bacteria/drug effects ; Surface-Active Agents/pharmacology/metabolism ; Palm Oil/chemistry/pharmacology ; Sunflower Oil/chemistry ; Saccharomycetales/metabolism ; Fungi/drug effects ; Soybean Oil/metabolism/pharmacology ; Oleic Acids ; }, abstract = {Starmerella bombicola is a native yeast strain producing sophorolipids as secondary metabolites. This study explores the production, characterization, and biological activities of sophorolipids and investigates the antimicrobial, anti-biofilm, and antifungal properties of sophorolipids produced from oil refinery wastes by the yeast Starmerella bombicola. The present work demonstrated that S. bombicola MTCC 1910 when grown in oil refinery wastes namely palm fatty acid distillates and soy fatty acid distillates enhanced the rate of sophorolipids production drastically in comparison to vegetable oil, sunflower oil used as hydrophobic feedstock. Sophorolipid yields were 18.14, 37.21, and 46.1 g/L with sunflower oil, palm, and soy fatty acid distillates respectively. The crude biosurfactants were characterized using TLC, FTIR, and HPLC revealing to be acetylated sophorolipids containing both the acidic and lactonic isomeric forms. The surface lowering and emulsifying properties of the sophorolipids from refinery wastes were significantly higher than the sunflower oil-derived sophorolipids. Also, all the sophorolipids exhibited strong antibacterial properties (minimum inhibitory concentrations were between 50 and 200 µg mL[-1]) against Salmonella typhimurium, Bacillus cereus, and Staphylococcus epidermidis and were validated with morphological analysis by Scanning electron microscopy. All the sophorolipids were potent biofilm inhibitors and eradicators (minimum biofilm inhibitory and eradication concentrations were between 12.5 to 1000 µg mL[-1]) for all the tested organisms. Furthermore, antifungal activities were also found to exhibit about 16-56% inhibition at 1 mg mL[-1] for fungal mycelial growth. Therefore, this endeavour of sophorolipids production using palm and soy fatty acid distillates not only opens up a window for the bioconversion of industrial wastes into productive biosurfactants but also concludes that sophorolipids from oil refinery wastes are potent antimicrobial, anti-biofilm, and antifungal agents, highlighting their potential in biotechnological and medical applications.}, }
@article {pmid39384180, year = {2024}, author = {Milli, G and Pellegrini, A and Listro, R and Fasolini, M and Pagano, K and Ragona, L and Pietrocola, G and Linciano, P and Collina, S}, title = {New LsrK Ligands as AI-2 Quorum Sensing Interfering Compounds against Biofilm Formation.}, journal = {Journal of medicinal chemistry}, volume = {67}, number = {20}, pages = {18139-18156}, pmid = {39384180}, issn = {1520-4804}, mesh = {*Biofilms/drug effects ; *Quorum Sensing/drug effects ; *Pseudomonas aeruginosa/drug effects ; *Staphylococcus aureus/drug effects ; *Homoserine/analogs &amp; derivatives/pharmacology/chemistry/chemical synthesis ; *Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; Ligands ; *Lactones/pharmacology/chemistry/chemical synthesis ; *Microbial Sensitivity Tests ; Bacterial Proteins/antagonists &amp; inhibitors/metabolism ; Structure-Activity Relationship ; Phosphotransferases (Alcohol Group Acceptor) ; Escherichia coli Proteins ; }, abstract = {Antimicrobial resistance (AMR) represents a critical global health crisis. An innovative strategy to deal with AMR is to interfere with biofilm formation and bacterial quorum sensing (QS). In this study, newly designed autoinducer-2 (AI-2)-inspired compounds in targeting biofilm-associated infections were evaluated for their ability to inhibit biofilm formation in Staphylococcus aureus and Pseudomonas aeruginosa. The most effective compounds, 5d, 5e, and 7b, exhibited potent antibiofilm activity with minimal inhibitory concentrations in the low microgram per mL range. Detailed biological assays confirmed that the antibiofilm activity was primarily driven through AI-2 QS inhibition rather than direct antimicrobial effects. The combination of different spectroscopic techniques, such as differential scanning fluorimetry, intrinsic tryptophan fluorescence, circular dichroism, and nuclear magnetic resonance, elucidated the binding between the compounds and the LsrK enzyme, a key player in AI-2 mediated QS. Our findings highlight the potential of these novel QS inhibitors as promising therapeutic agents against biofilm-associated infections.}, }
@article {pmid39384150, year = {2024}, author = {Wang, L and Tkhilaishvili, T and Jiang, Z and Pirlar, RF and Ning, Y and Millán Laleona, A and Wang, J and Tang, J and Wang, Q and Trampuz, A and Gonzalez Moreno, M and Zhang, X}, title = {Phage-liposome nanoconjugates for orthopedic biofilm eradication.}, journal = {Journal of controlled release : official journal of the Controlled Release Society}, volume = {376}, number = {}, pages = {949-960}, doi = {10.1016/j.jconrel.2024.09.049}, pmid = {39384150}, issn = {1873-4995}, mesh = {Animals ; *Biofilms/drug effects ; *Liposomes ; *Anti-Bacterial Agents/administration &amp; dosage/pharmacology/chemistry ; *Bacteriophages ; *Nanoconjugates/chemistry/administration &amp; dosage ; *Rats, Sprague-Dawley ; Prosthesis-Related Infections/prevention &amp; control ; Male ; Rats ; Drug Resistance, Multiple, Bacterial ; Osteomyelitis/drug therapy/microbiology ; }, abstract = {Infection by multidrug-resistant (MDR) bacteria has become one of the biggest threats to public health worldwide. One reason for the difficulty in treatment is the lack of proper delivery strategies into MDR bacterial biofilms, where the thick extracellular polymeric substance (EPS) layer impedes the penetration of antibiotics and nanoparticles. Here, we propose a novel bioactive nanoconjugate of drug-loaded liposomes and bacteriophages for targeted eradication of the MDR biofilms in orthopedic infections. Phage Sb-1, which has the ability to degrade EPS, was conjugated with antibiotic-loaded liposomes. Upon encountering the biofilm, phage Sb-1 degrades the EPS structure, thereby increasing the sensitivity of bacteria to antibiotics and allowing the antibiotics to penetrate deeply into the biofilm. As a result, effective removal of MDR bacterial biofilm was achieved with low dose of antibiotics, which was proved in this study by both in vitro and in vivo investigations. Notably, in the rat prosthetic joint infection (PJI) model, we found that the liposome-phage nanoconjugates could effectively decrease the bacterial load in the infected area and significantly promote osteomyelitis recovery. It is therefore believed that the conjugation of bacteriophage and liposomes could open new possibilities for the treatment of orthopedic infections, possibly other infections in the deep tissues.}, }
@article {pmid39384023, year = {2024}, author = {Thamayandhi, C and El-Tayeb, MA and Syed, SR and Sivaramakrishnan, R and Gunasekar, B}, title = {Antibacterial and anti-biofilm efficacy of selenium nanoparticles against Pseudomonas aeruginosa: Characterization and in vitro analysis.}, journal = {Microbial pathogenesis}, volume = {196}, number = {}, pages = {106998}, doi = {10.1016/j.micpath.2024.106998}, pmid = {39384023}, issn = {1096-1208}, mesh = {*Biofilms/drug effects ; *Pseudomonas aeruginosa/drug effects ; *Selenium/pharmacology/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Microbial Sensitivity Tests ; *Nanoparticles/chemistry ; Microscopy, Confocal ; Spectroscopy, Fourier Transform Infrared ; Bacterial Adhesion/drug effects ; }, abstract = {Pseudomonas aeruginosa (P. aeruginosa), a Gram-negative opportunistic pathogen, poses significant treatment challenges due to its antibiotic resistance and biofilm formation. This study investigates the anti-bacterial and anti-biofilm activities of chemically synthesized selenium nanoparticles (SeNPs) against P. aeruginosa. SeNPs were synthesized using ascorbic acid as a reducing agent and characterized. Biofilm formation was quantified using a modified microtiter plate method, and the anti-biofilm efficacy of SeNPs was evaluated using confocal microscopy and SEM. The P. aeruginosa isolates exhibited high resistance to piperacillin-tazobactam (60 %) and ceftazidime (59 %). SeNPs demonstrated a round shape with a diameter of 15-18 nm. UV-Vis spectra showed a peak at 275 nm, and XRD analysis revealed crystalline peaks corresponding to selenium. The FTIR spectra confirmed the presence of various functional groups. SeNPs significantly reduced biofilm formation in a dose-dependent manner, with MIC50 and MIC90 values of 60 μg/mL and 80 μg/mL, respectively. Confocal microscopy and SEM analysis showed a notable decrease in biofilm thickness and bacterial adherence post-SeNPs treatment. These findings suggest that SeNPs could be a promising alternative or adjunctive treatment option for combating antibiotic-resistant P. aeruginosa infections. Further research is warranted to explore the clinical applications of SeNPs in treating biofilm-associated infections.}, }
@article {pmid39383826, year = {2025}, author = {Wang, D and Wen, S and Liu, H and Liu, P and Xiong, J and Wu, Y and Li, Z and Tian, Z and Liu, B and Xu, D and Gu, T and Wang, F}, title = {Mitigation of biocorrosion of X80 carbon steel by a shale microbiome biofilm using a green biocide enhanced by d-amino acids.}, journal = {Bioelectrochemistry (Amsterdam, Netherlands)}, volume = {161}, number = {}, pages = {108831}, doi = {10.1016/j.bioelechem.2024.108831}, pmid = {39383826}, issn = {1878-562X}, mesh = {*Biofilms/drug effects ; Corrosion ; *Steel/chemistry ; *Microbiota/drug effects ; *Amino Acids ; *Disinfectants/pharmacology ; Carbon/chemistry ; Oil and Gas Fields/microbiology ; Green Chemistry Technology ; }, abstract = {Microbiologically influenced corrosion (MIC) in shale gas field is a major threat with the hydraulic fracturing fluid injected into the subsurface. In this study, the microbiome collected from a shale gas produced water sample was extracted and cultivated in ATCC 1249 medium modified with 10 g/L NaCl anaerobically at 30 °C. d-amino acids, which were reported as biocide enhancers, were found to enhance 2,2-dibromo-3-nitrilopropionamide (DBNPA) biocide on the mitigation of shale microbiome MIC on X80 carbon steel. The combination of 50 ppm (w/w) d-leucine + 50 ppm d-alanine + 1 ppm d-tyrosine had the best enhancement effect on 50 ppm DBNPA with 84 % less weight loss, and 67 % lower corrosion current density (icorr) compared to 50 ppm DBNPA alone. The corrosion data were consistent with the enhanced biofilm inhibition observation. The experimental data also indicated that d-tyrosine used alone at a low dosage of 1 ppm enhanced DBNPA considerably, with 44 % less weight loss and 47 % less icorr. The electrochemical results showed the positive response of shale gas microbiome biofilm to the injected magnetite nanoparticles indicating the extracellular electron transfer might be a main mechanism for its corrosion.}, }
@article {pmid39383754, year = {2024}, author = {Wu, Y and Sun, Q and Zhou, Z and Wang, Z and Fu, H}, title = {Efficient degradation of carbamazepine and metagenomic investigations of anodic biofilm in microbial fuel cells.}, journal = {Journal of environmental management}, volume = {370}, number = {}, pages = {122743}, doi = {10.1016/j.jenvman.2024.122743}, pmid = {39383754}, issn = {1095-8630}, mesh = {*Carbamazepine/metabolism ; *Bioelectric Energy Sources ; *Biofilms ; *Metagenomics ; Electrodes ; Biodegradation, Environmental ; }, abstract = {Environmental contamination with carbamazepine is a considerable global problem. In this study, two-compartment microbial fuel cells (MFCs) were constructed to investigate the degradation performance of carbamazepine, and the degradation mechanism was further explored by using metagenomic analysis. The results showed that MFCs exhibited excellent carbamazepine removal performance and also generated electricity. The removal rate of carbamazepine reached 73.56% over the 72-h operation period, which was 3.09 times higher than that of the traditional anaerobic method, and the peak voltage of the MFCs could reach 416 mV. Metagenomics revealed significant differences in microbial community composition between MFCs and the traditional anaerobic method (p < 0.05), and Proteobacteria (81.57%) was predominant bacterial phyla during the degradation of carbamazepine by MFCs. Among them, the microbial communities at the genus level were mainly composed of Pseudomonas, Pusillimonas, Burkholderia, Stenotrophomonas, Methyloversatilis and Nitrospirillum. Kyoto Encyclopedia of genes and genomes (KEGG) metabolic pathway analysis showed that the number of genes related to carbon and nitrogen metabolism increased by 85.12% and 142.25%, respectively. Importantly, a greater number of genes of microbial grown on the surface of anode were assigned to denitrification and the degradation of aromatic compounds. This research provides a cost-effective method for treating wastewater contaminated with carbamazepin.}, }
@article {pmid39383746, year = {2024}, author = {Das, S and Pradhan, T and Panda, SK and Behera, AD and Kumari, S and Mallick, S}, title = {Bacterial biofilm-mediated environmental remediation: Navigating strategies to attain Sustainable Development Goals.}, journal = {Journal of environmental management}, volume = {370}, number = {}, pages = {122745}, doi = {10.1016/j.jenvman.2024.122745}, pmid = {39383746}, issn = {1095-8630}, mesh = {*Biofilms ; *Environmental Restoration and Remediation/methods ; *Sustainable Development ; Bacteria/metabolism ; }, abstract = {Bacterial biofilm is a structured bacterial community enclosed within a three-dimensional polymeric matrix, governed by complex signaling pathways, including two-component systems, quorum sensing, and c-di-GMP, which regulate its development and resistance in challenging environments. The genetic configurations within biofilm empower bacteria to exhibit significant pollutant remediation abilities, offering a promising strategy to tackle diverse ecological challenges and expedite progress toward Sustainable Development Goals (SDGs). Biofilm-based technologies offer advantages such as high treatment efficiency, cost-effectiveness, and sustainability compared to conventional methods. They significantly contribute to agricultural improvement, soil fertility, nutrient cycling, and carbon sequestration, thereby supporting SDG 1 (No poverty), SDG 2 (Zero hunger), SDG 13 (Climate action), and SDG 15 (Life on land). In addition, biofilm facilitates the degradation of organic-inorganic pollutants from contaminated environments, aligning with SDG 6 (Clean water and sanitation) and SDG 14 (Life below water). Bacterial biofilm also has potential applications in industrial innovation, aligning SDG 7 (Affordable and clean energy), SDG 8 (Decent work and economic growth), and SDG 9 (Industry, innovation, and infrastructure). Besides, bacterial biofilm prevents several diseases, aligning with SDG 3 (Good health and well-being). Thus, bacterial biofilm-mediated remediation provides advanced opportunities for addressing environmental issues and progressing toward achieving the SDGs. This review explores the potential of bacterial biofilms in addressing soil pollution, wastewater, air quality improvement, and biodiversity conservation, emphasizing their critical role in promoting sustainable development.}, }
@article {pmid39381779, year = {2024}, author = {Sivori, F and Cavallo, I and Truglio, M and De Maio, F and Sanguinetti, M and Fabrizio, G and Licursi, V and Francalancia, M and Fraticelli, F and La Greca, I and Lucantoni, F and Camera, E and Mariano, M and Ascenzioni, F and Cristaudo, A and Pimpinelli, F and Di Domenico, EG}, title = {Staphylococcus aureus colonizing the skin microbiota of adults with severe atopic dermatitis exhibits genomic diversity and convergence in biofilm traits.}, journal = {Biofilm}, volume = {8}, number = {}, pages = {100222}, pmid = {39381779}, issn = {2590-2075}, abstract = {Atopic dermatitis (AD) is a chronic inflammatory skin disorder exacerbated by Staphylococcus aureus colonization. The specific factors that drive S. aureus overgrowth and persistence in AD remain poorly understood. This study analyzed skin barrier functions and microbiome diversity in lesional (LE) and non-lesional (NL) forearm sites of individuals with severe AD compared to healthy control subjects (HS). Notable differences were found in transepidermal water loss, stratum corneum hydration, and microbiome composition. Cutibacterium was more prevalent in HS, while S. aureus and S. lugdunensis were predominantly found in AD LE skin. The results highlighted that microbial balance depends on inter-species competition. Specifically, network analysis at the genus level demonstrated that overall bacterial correlations were higher in HS, indicating a more stable microbial community. Notably, network analysis at the species level revealed that S. aureus engaged in competitive interactions in NL and LE but not in HS. Whole-genome sequencing (WGS) showed considerable genetic diversity among S. aureus strains from AD. Despite this variability, the isolates exhibited convergence in key phenotypic traits such as adhesion and biofilm formation, which are crucial for microbial persistence. These common phenotypes suggest an adaptive evolution, driven by competition in the AD skin microenvironment, of S. aureus and underscoring the interplay between genetic diversity and phenotypic convergence in microbial adaptation.}, }
@article {pmid39381466, year = {2024}, author = {Kaintura, A and Ramar, K}, title = {Comparative Evaluation of Biofilm Formation on Temporization Crown Materials Used in the Rehabilitation of Primary Dentition With Different Polishing Materials: An In Vitro Study.}, journal = {Cureus}, volume = {16}, number = {9}, pages = {e68944}, pmid = {39381466}, issn = {2168-8184}, abstract = {Introduction Advancements in dental materials have enhanced aesthetic treatments for managing dental caries and injuries in primary dentition. Bis-acryl composite-based temporization materials are now preferred for restoring primary crowns due to their superior properties. However, prolonged exposure to dietary and hygienic factors can lead to discoloration and roughness, making efficient polishing essential to prevent plaque buildup. Objective This study aims to evaluate Streptococcus mutans biofilm formation on temporization material polished with different polishing systems. Methods This study tested bis-acryl methacrylate temporization material. Thirty disk-shaped specimens were prepared and divided into three groups according to the polishing system used (n = 10 per group): Shofu Super Snap mini kit (Shofu, San Marcos, CA), aluminum oxide polishing paste, and propol polishing paste. Each group's specimens were polished according to the manufacturer's instructions. Surface roughness (SR), scanning electron microscopy (SEM) morphological analysis, and Streptococcus mutans biofilm formation were assessed for each group. Results The results showed significant differences in roughness average (Ra) values among the polishing materials, with the Shofu Super Snap mini kit having the highest roughness (Ra = 2.04), followed by propol polishing paste (Ra = 1.30) and aluminum oxide paste (Ra = 0.75). Additionally, polishing methods significantly affected mean colony-forming unit (CFU) levels, with the first group having the highest mean CFU value (0.24), with SEM images showing substantial biofilm formation by Streptococcus mutans. Conclusion Bacterial biofilm formation on the aluminum oxide paste group's surface differed from that on the propol polishing paste and aluminum oxide disc groups. The polishing techniques that we tested significantly influenced surface properties and biofilm formation. These findings suggest that selecting an appropriate polishing system can reduce the risk of gingival inflammation associated with temporization materials.}, }
@article {pmid39381027, year = {2024}, author = {Szymczak, M and Golec, P}, title = {Long-Term Effectiveness of Engineered T7 Phages Armed with Silver Nanoparticles Against Escherichia coli Biofilm.}, journal = {International journal of nanomedicine}, volume = {19}, number = {}, pages = {10097-10105}, pmid = {39381027}, issn = {1178-2013}, mesh = {*Biofilms/drug effects ; *Metal Nanoparticles/chemistry ; *Silver/chemistry/pharmacology ; *Escherichia coli/drug effects ; *Bacteriophage T7/physiology ; Anti-Bacterial Agents/pharmacology/chemistry ; Phage Therapy ; Escherichia coli Infections ; Microbial Sensitivity Tests ; }, abstract = {The escalating threat of antibiotic-resistant bacteria, particularly those forming biofilm structures, underscores the urgent need for alternative treatment strategies. Bacteriophages have emerged as promising agents for combating bacterial infections, especially those associated with biofilm formation. However, the efficacy of phage therapy can be limited by the development of bacterial resistance and biofilm regrowth. Interestingly, phages could be combined with other agents, such as metal nanoparticles, to enhance their antibacterial effectiveness. Since the therapeutic strategy of using phages and metal nanoparticles has been developed relatively recently, evaluating its efficacy under various conditions is essential, with a particular focus on the duration of activity. This study tested the hypothesis that a novel approach to combating bacterial biofilms, based on phages armed with silver nanoparticles (AgNPs), would exhibit enhanced activity over an extended period after application. In this work, we investigated the potential of engineered T7 phages armed with AgNPs for eradicating Escherichia coli biofilm. We demonstrated that such biomaterial exhibits sustained antimicrobial activity even after prolonged exposure. Compared to phages alone or AgNPs alone, the biomaterial significantly enhances biofilm eradication, particularly after 48 hours of treatment. These findings highlight the potential of synergistic phage-nanoparticle strategies for combatting biofilm-associated infections.}, }
@article {pmid39377591, year = {2024}, author = {Shi, W and Li, Y and Zhang, W}, title = {Screening and functional characterization of isocitrate lyase AceA in the biofilm formation of Vibrio alginolyticus.}, journal = {Applied and environmental microbiology}, volume = {90}, number = {11}, pages = {e0069724}, pmid = {39377591}, issn = {1098-5336}, support = {LR20C190001//MOST | NSFC | NSFC-Zhejiang Joint Fund | | Science Fund for Distinguished Young Scholars of Zhejiang Province ()/ ; 31972833//MOST | National Natural Science Foundation of China (NSFC)/ ; 2021J062//NBST | Natural Science Foundation of Ningbo Municipality ()/ ; NA//K.C. Wong Magna Fund in Ningbo City/ ; }, mesh = {*Biofilms/growth &amp; development ; *Vibrio alginolyticus/genetics/physiology/enzymology ; *Isocitrate Lyase/genetics/metabolism ; *Bacterial Proteins/genetics/metabolism ; Gene Expression Regulation, Bacterial ; Gene Expression Profiling ; }, abstract = {Biofilm is a well-known sessile lifestyle for bacterial pathogens, but a little is known about the mechanism on biofilm formation in Vibrio alginolyticus. In this study, we screened V. alginolyticus strains with strong biofilm formation ability from coastal seawater. The antibiotic resistance of the biofilm cells (BFs) was higher than that of the planktonic cells (PTs). To study the genes and pathways involved in biofilm formation, we performed transcriptome analysis of the BFs and PTs of V. alginolyticus R9. A total of 685 differentially expressed genes (DEGs) were upregulated, and 517 DEGs were downregulated in the BFs. The upregulated DEGs were significantly enriched in several pathways including glyoxylate and dicarboxylate metabolism, while the downregulated genes were significantly enriched in the flagellar assembly pathways. The key gene involved in glyoxylate shunt, aceA, was cloned, and ΔaceA mutant was constructed to determine the function of AceA in carbon source utilization, biofilm formation, and virulence. Real-time reverse transcription PCR showed that the expression of aceA was higher at the mature stage but lower at the disperse stage of biofilm formation, and the expression of the flagellar related genes was upregulated in ΔaceA. This is the first study to illustrate the global gene expression profile during the biofilm formation of V. alginolyticus, and isocitrate lyase AceA, the key enzyme involved in glyoxylate shunt, was shown to maintain biofilms accompanied by downregulation of flagellation but promoted dispersal of BFs at the late stage.IMPORTANCEBiofilms pose serious public problems, not only protecting the cells in it from environmental hazard but also affecting the composition and abundance of bacteria, algae, fungi, and protozoa. The important opportunistic pathogen Vibrio alginolyticus is extremely ubiquitously present in seawater, and it also exhibited a strong ability to form biofilm; thus, investigation on the biofilm formation of V. alginolyticus at molecular level is fundamental for the deeper exploration of the environmental concerns arose by biofilm. In this study, transcriptome analysis of biofilm cells (BFs) and planktonic cells (PTs) from V. alginolyticus was performed and AceA was screened to play an important role in biofilm formation. AceA was shown to maintain biofilms accompanied by downregulation of flagellation but promoted dispersal of BFs at the disperse stage. This method was helpful to further understand the ability and mechanism of V. alginolyticus biofilm formation and provide clues for prevention of V. alginolyticus infection.}, }
@article {pmid39377107, year = {2024}, author = {Sampaio, C and Cusicanqui Méndez, DA and Buzalaf, MAR and Pessan, JP and Cruvinel, T}, title = {Influence of different growth conditions on the composition and acidogenicity of saliva-derived microcosm biofilm and their effects on enamel demineralization.}, journal = {Biofouling}, volume = {40}, number = {10}, pages = {743-753}, doi = {10.1080/08927014.2024.2410781}, pmid = {39377107}, issn = {1029-2454}, mesh = {*Biofilms/growth &amp; development ; *Saliva/chemistry ; *Dental Enamel/microbiology ; *Tooth Demineralization ; Hydrogen-Ion Concentration ; Humans ; Culture Media/chemistry ; Lactic Acid/metabolism ; Lactobacillus/physiology/growth &amp; development ; Streptococcus/physiology/growth &amp; development ; Animals ; }, abstract = {This study compared the influence of growth conditions on the composition and acidogenicity of saliva-derived microcosm biofilms and enamel demineralization. Biofilms grown in sucrose-supplemented modified McBain medium, containing 25/50 mmol/L PIPES (buffer), under anaerobiosis/microaerophilia, for 3 and 7 days were evaluated for their acidogenicity, microbial composition, matrix, and enamel mineral content. The viability of total lactobacilli was higher in the group containing 25 mmol/L PIPES grown under anaerobiosis, which also showed lower pH values. The viability of total streptococci and total microorganisms was significantly higher at 7 days in the groups with 50 mmol/L PIPES than at 3 days, regardless of the incubation atmosphere. No significant differences were observed in lactic acid, calcium, superficial hardness loss, or lesion depth. In conclusion, the incubation atmosphere, buffer content in the growth media, and duration of biofilm formation displayed species-varied influence on microcosm biofilms, without causing significant changes in acid metabolism or enamel demineralization.}, }
@article {pmid39376521, year = {2024}, author = {Pakeeraiah, K and Swain, PP and Sahoo, A and Panda, PK and Mahapatra, M and Mal, S and Sahoo, RK and Sahu, PK and Paidesetty, SK}, title = {Multimodal antibacterial potency of newly designed and synthesized Schiff's/Mannich based coumarin derivatives: potential inhibitors of bacterial DNA gyrase and biofilm production.}, journal = {RSC advances}, volume = {14}, number = {43}, pages = {31633-31647}, pmid = {39376521}, issn = {2046-2069}, abstract = {The briskened urge to develop potential antibacterial candidates against multidrug-resistant pathogens has motivated the present research study. Herein, newly synthesized coumarin derivatives with azomethine and amino-methylated as the functional groups have been focused on their antibacterial efficacy. The study proposed two distinct series: 3-acetyl substituted coumarin derivatives, followed by the Schiff base approach (5a-5i), and formaldehyde-secondary cyclic amine-based derivatives (7a-7g), using the Mannich base approach, further the compounds have been confirmed through various spectral studies. Further, target-specific binding affinity has been affirmed via in silico study. In vitro antibacterial study suggested compounds 5d and 5f to be most effective against S. aureus and multidrug-resistant K. pneumoniae, with MIC values of 8 and 16 μg mL[-1]. Among them, the compounds 5d and 5f showed excellent binding scores against different bacterial gyrase compared to the standard novobiocin. Based on RMRS, RMSF, Rg, and H-bond plots, MD simulation study at 100 ns also suggested better stability of 5d inside gyraseB of E. coli than the complex of E. coli-GyrB-novobiocin. The toxicity and pharmacokinetic profiles showed favorable drug-likeness. Overall, systematic in vitro and in silico assessment suggested that multimodal antibacterial derivatives 5d and 5f strongly inhibit both bacterial DNA gyrase and biofilm formation of drug-resistant pathogens, suggesting their potency in mainstream antibacterial therapy.}, }
@article {pmid39376426, year = {2024}, author = {Mujahid, ZA and Palal, SS and Gopan, G and Ramabhadraiah, AK}, title = {Biofilm Producing Organisms and Their Antibiotic Sensitivity in Chronic Suppurative Otitis Media: A Cross-Sectional Study.}, journal = {Indian journal of otolaryngology and head and neck surgery : official publication of the Association of Otolaryngologists of India}, volume = {76}, number = {5}, pages = {3886-3894}, pmid = {39376426}, issn = {2231-3796}, abstract = {Chronic Suppurative Otitis Media (CSOM) is an inflammation of the mucoperiosteal lining of the middle ear cleft. Recently, biofilms have been discovered to play a pivotal role in the pathogenesis of CSOM. A biofilm is a bacterial aggregation that adheres to the mucosal surfaces and is connected with an extracellular matrix. Biofilms enhance antibiotic resistance, facilitate genetic alterations and amplify competence to combat host immunity. This study aims to identify the spectrum of biofilm-producers in CSOM and investigate their antibiotic sensitivity. Samples (648) were obtained from the deeper part of external auditory meatus of patients with CSOM. Pus samples were collected and processed for culture sensitivity. Biofilms detected. The findings were compiled and statistically analyzed. Out of 500 culture-positive samples, most commonly isolated bacteria was Pseudomonas (62.6%), followed by MRSA (13.8%). Biofilm-producers were 350, with 119 being strong, 167 moderate, and 64 weak. Biofilms were produced by 70% of the isolates, with Pseudomonas producing the most (74.6%), followed by MRSA. Gentamicin was the most effective antibiotic against biofilm-producers. Amoxicillin-Clavulanic Acid, Ceftriaxone, Cefuroxime, and Minocyclin were resistant. Pseudomonas had the highest sensitivity to Levofloxacin (96.6%), followed by Ceftazidime and Ciprofloxacin. Pseudomonas was resistant to Cefuroxime, Amoxicillin-Clavulanic acid and Linezolid. Multi-drug resistance has been widespread among CSOM causal species, particularly in biofilm producers. Thus, screening for biofilm formation, in addition to the standard antibiogram, must be undertaken as part of CSOM protocol. This will address the multi-drug resistance and select an appropriate treatment modality.}, }
@article {pmid39375363, year = {2024}, author = {Lander, SM and Fisher, G and Everett, BA and Tran, P and Prindle, A}, title = {Secreted nucleases reclaim extracellular DNA during biofilm development.}, journal = {NPJ biofilms and microbiomes}, volume = {10}, number = {1}, pages = {103}, pmid = {39375363}, issn = {2055-5008}, support = {R35 GM147170/GM/NIGMS NIH HHS/United States ; NSF 2239567//National Science Foundation (NSF)/ ; S10 OD025194/OD/NIH HHS/United States ; W911NF-21-1-0291//United States Department of Defense | United States Army | U.S. Army Research, Development and Engineering Command | Army Research Office (ARO)/ ; P41 GM108569/GM/NIGMS NIH HHS/United States ; P30 CA060553/CA/NCI NIH HHS/United States ; 1R35GM147170-01//U.S. Department of Health &amp; Human Services | National Institutes of Health (NIH)/ ; F31 GM143907/GM/NIGMS NIH HHS/United States ; F31GM143907//U.S. Department of Health &amp; Human Services | NIH | National Institute of General Medical Sciences (NIGMS)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Bacillus subtilis/genetics ; *DNA, Bacterial/genetics ; Bacterial Proteins/genetics/metabolism ; Deoxyribonucleases/metabolism/genetics ; }, abstract = {DNA is the genetic code found inside all living cells and its molecular stability can also be utilized outside the cell. While extracellular DNA (eDNA) has been identified as a structural polymer in bacterial biofilms, whether it persists stably throughout development remains unclear. Here, we report that eDNA is temporarily invested in the biofilm matrix before being reclaimed later in development. Specifically, by imaging eDNA dynamics within undomesticated Bacillus subtilis biofilms, we found eDNA is produced during biofilm establishment before being globally degraded in a spatiotemporally coordinated pulse. We identified YhcR, a secreted Ca[2+]-dependent nuclease, as responsible for eDNA degradation in pellicle biofilms. YhcR cooperates with two other nucleases, NucA and NucB, to reclaim eDNA for its phosphate content in colony biofilms. Our results identify extracellular nucleases that are crucial for eDNA reclamation during biofilm development and we therefore propose a new role for eDNA as a dynamic metabolic reservoir.}, }
@article {pmid39373511, year = {2024}, author = {Richards, B and Robertson, S and Martinez Pomares, L and Cámara, M}, title = {Development of a Polymicrobial Colony Biofilm Model to Test Antimicrobials in Cystic Fibrosis.}, journal = {Journal of visualized experiments : JoVE}, volume = {}, number = {211}, pages = {}, doi = {10.3791/67213}, pmid = {39373511}, issn = {1940-087X}, mesh = {*Cystic Fibrosis/microbiology ; *Biofilms/drug effects/growth &amp; development ; Humans ; Anti-Bacterial Agents/pharmacology ; Pseudomonas aeruginosa/drug effects/physiology ; Models, Biological ; Microbial Sensitivity Tests/methods ; }, abstract = {A range of bacteria biofilm models exist for the testing of antibiotics. However, many of these are limited to a single experimental output, such as colony-forming units or metabolic activity. Furthermore, many biofilm models do not reflect the biological and physiochemical properties of the human host environment. This is an important issue in many conditions, but most noticeably in cystic fibrosis (CF). A large proportion of people with CF suffer from both chronic and intermittent infections, and in vitro, antibiotic susceptibility testing poorly correlates with patient treatment outcomes. Some biofilm models incorporate CF lung-relevant media, including synthetic sputum mimics, but do not consider the polymicrobial nature of the environment, which alters biofilm architecture, physiology, and the way microbes respond to treatment. The solid-air interface colony biofilm model described here is highly adaptable and incorporates both CF-relevant media and a polymicrobial context. This model can also be used for mid-throughput screening of antimicrobials and to study their effect on polymicrobial dynamics. Output measurements from the model can be colony-forming units, metabolic activity, and confocal microscopy analysis. The model can easily be adapted to different microorganisms, media, temperatures, and variable oxygen conditions and can be used to test a wide range of chemical, biological, and physical treatments.}, }
@article {pmid39373165, year = {2025}, author = {Zhang, TH and Yang, YK and Feng, YM and Luo, ZJ and Wang, MW and Qi, PY and Zeng, D and Liu, HW and Liao, YM and Meng, J and Zhou, X and Liu, LW and Yang, S}, title = {Engineering the novel azobenzene-based molecular photoswitches for suppressing bacterial infection through dynamic regulation of biofilm formation.}, journal = {Pest management science}, volume = {81}, number = {2}, pages = {585-598}, doi = {10.1002/ps.8453}, pmid = {39373165}, issn = {1526-4998}, support = {//National Key Research and Development Program of China (2022YFD1700300)/ ; //National Natural Science Foundation of China (32372610, U23A20201, 32160661, 32202359/ ; //the Central Government Guides Local Science and Technology Development Fund Projects [Qiankehezhongyindi [2024]007]/ ; 32372610//National Natural Science Foundation of China/ ; U23A20201//National Natural Science Foundation of China/ ; 32160661//National Natural Science Foundation of China/ ; 32202359//National Natural Science Foundation of China/ ; 2022YFD1700300//National Key Research and Development Program of China/ ; [2024]007//Central Government Guides Local Science and Technology Development Fund Projects/ ; }, mesh = {*Biofilms/drug effects ; *Azo Compounds/pharmacology/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; }, abstract = {BACKGROUND: Bacterial biofilm is a strong fortress for bacteria to resist harsh external environments, which can enhance their tolerance and exacerbate the drug/pesticide resistance risk. Currently, photopharmacology provides an advanced approach via precise spatiotemporal control for regulating biological activities by light-controlling the molecular configurations, thereby having enormous potential in the development of drug/pesticides.<br><br>RESULTS: To further expand the photopharmacology application for discovering new antibiofilm agents, we prepared a series of light-controlled azo-active molecules and explored their photo isomerization, fatigue resistance, and anti-biofilm performance. Furthermore, their mechanisms of inhibiting biofilm formation were systematically investigated. Overall, designed azo-derivative A11 featured excellent anti-Xoo activity with an half-maximal effective concentration (EC50) value of 5.45&#x2009;&#x3bc;g&#x2009;mL[-1], and the EC50 value could be further elevated to 2.19&#x2009;&#x3bc;g&#x2009;mL[-1] after ultraviolet irradiation (converted as cis-configuration). The photo-switching behavior showed that A11 had outstanding anti-fatigue properties. An in-depth analysis of the action mechanism showed that A11 could effectively inhibit biofilm formation and the expression of relevant virulence factors. This performance could be dynamically regulated via loading with private light-switch property.<br><br>CONCLUSION: In this work, designed light-controlled azo molecules provide a new model for resisting bacterial infection via dynamic regulation of bacterial biofilm formation. &#xa9; 2024 Society of Chemical Industry.}, }
@article {pmid39372729, year = {2025}, author = {Yang, Y and Yan, J and Olson, R and Jiang, X}, title = {Comprehensive Genomic and Evolutionary Analysis of Biofilm Matrix Clusters and Proteins in the Vibrio Genus.}, journal = {bioRxiv : the preprint server for biology}, volume = {}, number = {}, pages = {}, doi = {10.1101/2024.08.19.608685}, pmid = {39372729}, issn = {2692-8205}, abstract = {Vibrio cholerae pathogens cause cholera, an acute diarrheal disease resulting in significant morbidity and mortality worldwide. Biofilms in vibrios enhance their survival in natural ecosystems and facilitate transmission during cholera outbreaks. Critical components of the biofilm matrix include the Vibrio polysaccharides produced by the vps-1 and vps-2 gene clusters and the biofilm matrix proteins encoded in the rbm gene cluster, together comprising the biofilm matrix cluster. However, the biofilm matrix clusters and their evolutionary patterns in other Vibrio species remain underexplored. In this study, we systematically investigated the distribution, diversity, and evolution of biofilm matrix clusters and proteins across the Vibrio genus. Our findings reveal that these gene clusters are sporadically distributed throughout the genus, even appearing in species phylogenetically distant from V. cholerae. Evolutionary analysis of the major biofilm matrix proteins RbmC and Bap1 shows that they are structurally and sequentially related, having undergone structural domain and modular alterations. Additionally, a novel loop-less Bap1 variant was identified, predominantly represented in two phylogenetically distant Vibrio cholerae subspecies clades that share specific gene groups associated with the presence or absence of the protein. Furthermore, our analysis revealed that rbmB, a gene involved in biofilm dispersal, shares a recent common ancestor with Vibriophage tail proteins, suggesting that phages may mimic host functions to evade biofilm-associated defenses. Our study offers a foundational understanding of the diversity and evolution of biofilm matrix clusters in vibrios, laying the groundwork for future biofilm engineering through genetic modification.}, }
@article {pmid39370609, year = {2024}, author = {Islam, MS and Alatishe, A and Lee-Lopez, CC and Serrano, F and Yukl, ET}, title = {H-NOX Influences Biofilm Formation, Central Metabolism, and Quorum Sensing in Paracoccus denitrificans.}, journal = {Journal of proteome research}, volume = {23}, number = {11}, pages = {4988-5000}, pmid = {39370609}, issn = {1535-3907}, mesh = {*Biofilms/growth &amp; development ; *Paracoccus denitrificans/metabolism/genetics ; *Quorum Sensing ; *Bacterial Proteins/metabolism/genetics ; Proteomics/methods ; 4-Butyrolactone/analogs &amp; derivatives/metabolism ; Pyruvic Acid/metabolism ; Signal Transduction ; Heme-Binding Proteins/metabolism ; Metabolic Networks and Pathways/genetics ; Gene Expression Regulation, Bacterial ; Hemeproteins/metabolism/genetics ; }, abstract = {The transition from planktonic to biofilm growth in bacteria is often accompanied by greater resistance to antibiotics and other stressors, as well as distinct alterations in physical traits, genetic activity, and metabolic restructuring. In many species, the heme nitric oxide/oxygen binding proteins (H-NOX) play an important role in this process, although the signaling mechanisms and pathways in which they participate are quite diverse and largely unknown. In Paracoccus denitrificans, deletion of the hnox gene results in a severe biofilm-deficient phenotype. Quantitative proteomics was used to assemble a comprehensive data set of P. denitrificans proteins showing altered abundance of those involved in several important metabolic pathways. Further, decreased levels of pyruvate and elevated levels of C16 homoserine lactone were detected for the Δhnox strain, associating the biofilm deficiency with altered central carbon metabolism and quorum sensing, respectively. These results expand our knowledge of the important role of H-NOX signaling in biofilm formation.}, }
@article {pmid39369508, year = {2024}, author = {Jang, Y and Lee, SH and Kim, NK and Park, HD}, title = {Metagenomic analysis reveals abundance of mixotrophic, heterotrophic, and homoacetogenic bacteria in a hydrogen-based membrane biofilm reactor.}, journal = {Water research}, volume = {267}, number = {}, pages = {122564}, doi = {10.1016/j.watres.2024.122564}, pmid = {39369508}, issn = {1879-2448}, mesh = {*Biofilms ; *Bioreactors/microbiology ; *Hydrogen/metabolism ; *Bacteria/metabolism/genetics ; *Metagenomics ; *Heterotrophic Processes ; Denitrification ; Metagenome ; }, abstract = {Heterotrophic microorganisms are frequently observed in hydrogenotrophic denitrification systems and are presumed to contribute to their improved performance. However, their roles and metabolic pathways in the hydrogen-based membrane biofilm reactor (H2-MBfR) system remain unclear. The objective of this study was to elucidate the underlying mechanisms driving heterotrophic denitrification. For this purpose, metagenomic analysis was conducted on an H2-MBfR showing higher denitrification performance, focusing on the metabolic function of the microbial community. Functional genes related to H2 oxidation, organic carbon metabolism, and denitrification were the major targets of interest. This analysis revealed a substantial number of genes associated with the oxidation of organic carbon compounds in the biofilm, suggesting its potential for heterotrophic denitrification. Investigation of the genes of interest in metagenome-assembled genomes (MAGs) has demonstrated a predominance of mixotrophs or heterotrophs rather than obligate autotrophs. Notably, MAGs exhibiting the highest abundance of genes of interest were affiliated with Hydrogenophaga and Thauera, implying their significant role in denitrifying the H2-MBfR as mixotrophs utilizing both H2 and organic substrates. The identification of 11 MAGs, presumed to originate from homoacetogens suggested that acetate might contribute to the proliferation of heterotrophs. Based on these metagenomic findings, possible metabolic pathways were identified to explain heterotrophic denitrification within the H2-MBfR biofilms.}, }
@article {pmid39369013, year = {2024}, author = {Klein, EM and Heintz, H and Wurst, R and Schuldt, S and Hähl, H and Jacobs, K and Gescher, J}, title = {Comparative analysis of the influence of BpfA and BpfG on biofilm development and current density in Shewanella oneidensis under oxic, fumarate- and anode-respiring conditions.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {23174}, pmid = {39369013}, issn = {2045-2322}, mesh = {*Shewanella/genetics/physiology/metabolism ; *Biofilms/growth &amp; development ; *Fumarates/metabolism ; *Electrodes ; Bacterial Proteins/genetics/metabolism ; Bioelectric Energy Sources/microbiology ; Oxygen/metabolism ; }, abstract = {Biofilm formation by Shewanella oneidensis has been extensively studied under oxic conditions; however, relatively little is known about biofilm formation under anoxic conditions and how biofilm architecture and composition can positively influence current generation in bioelectrochemical systems. In this study, we utilized a recently developed microfluidic biofilm analysis setup with automated 3D imaging to investigate the effects of extracellular electron acceptors and synthetic modifications to the extracellular polymeric matrix on biofilm formation. Our results with the wild type strain demonstrate robust biofilm formation even under anoxic conditions when fumarate is used as the electron acceptor. However, this pattern shifts when a graphite electrode is employed as the electron acceptor, resulting in biofilm formation falling below the detection limit of the optical coherence tomography imaging system. To manipulate biofilm formation, we aimed to express BpfG with a single amino acid substitution in the catalytic center (C116S) and to overexpress bpfA. Our analyses indicate that, under oxic conditions, overarching mechanisms predominantly influence biofilm development, rather than the specific mutations we investigated. Under anoxic conditions, the bpfG mutation led to a quantitative increase in biofilm formation, but both strains exhibited significant qualitative changes in biofilm architecture compared to the controls. When an anode was used as the sole electron acceptor, both the bpfA and bpfG mutations positively impacted mean current density, yielding a 1.8-fold increase for each mutation.}, }
@article {pmid39368992, year = {2024}, author = {Margot, C and Rhoads, W and Gabrielli, M and Olive, M and Hammes, F}, title = {Dynamics of drinking water biofilm formation associated with Legionella spp. colonization.}, journal = {NPJ biofilms and microbiomes}, volume = {10}, number = {1}, pages = {101}, pmid = {39368992}, issn = {2055-5008}, support = {Aramis nr.:4.20.01//Bundesamt f&#xfc;r Lebensmittelsicherheit und Veterin&#xe4;rwesen (Federal Food Safety and Veterinary Office)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Legionella/physiology/classification/growth &amp; development/genetics ; *Drinking Water/microbiology ; *RNA, Ribosomal, 18S/genetics ; Water Microbiology ; Sequence Analysis, DNA ; }, abstract = {Understanding how Legionella spp. proliferate in multispecies biofilms is essential to develop strategies to control their presence in building plumbing. Here, we analyzed biofilm formation and Legionella spp. colonization on new plumbing material during 8 weeks. Biofilm formation was characterized by an initial increase in intact cell concentrations up to 9.5 × 10[5] cells/cm[2], followed by a steady decrease. We identified Comamonas, Caulobacter, Schlegella, Blastomonas and Methyloversatilis as pioneer genera in the biofilm formation process. Importantly, L. pneumophila was the dominant Legionella spp. and rapidly colonized the biofilms, with culturable cell concentrations peaking at 3.1 × 10[4] MPN/cm[2] after 4 weeks already. Moreover, several Legionella species co-occurred and had distinct dynamics of biofilm colonization. Vermamoeba vermiformis (V. vermiformis) was the dominant protist identified with 18S rRNA gene amplicon sequencing. Together our results highlight that biofilm formation upon introduction of new building plumbing material is a dynamic process where pathogenic Legionella species can be part of the earliest colonizers.}, }
@article {pmid39368846, year = {2025}, author = {Hartono Adji, RP and Anshori, I and Manurung, RV and Taufiqqurrachman,  and Mahmudin, D and Daud, P and Kurniadi, DP and Pristianto, EJ and Rahman, AN and Desvasari, W and Sulistyaningsih,  and Mandasari, RD and Hiskia,  and Wiranto, G}, title = {Retraction notice to "A comprehensive study on transparent conducting oxides in compact microbial fuel cells: Integrated spectroscopic and electrochemical analyses for monitoring biofilm growth" [Biosens. Bioelectron. 250 (2024) 116067].}, journal = {Biosensors &amp; bioelectronics}, volume = {267}, number = {}, pages = {116812}, doi = {10.1016/j.bios.2024.116812}, pmid = {39368846}, issn = {1873-4235}, }
@article {pmid39368628, year = {2024}, author = {Mei, N and Jia, F and Wang, H and Hu, Z and Han, B and Chen, Y and Zhao, X and Han, X and Zhang, J and Li, D and Yao, H and Guo, J}, title = {Partitioned granular sludge coupling with membrane-aerated biofilm reactor for efficient autotrophic nitrogen removal.}, journal = {Bioresource technology}, volume = {414}, number = {}, pages = {131570}, doi = {10.1016/j.biortech.2024.131570}, pmid = {39368628}, issn = {1873-2976}, mesh = {*Sewage/microbiology ; *Biofilms ; *Nitrogen/metabolism ; *Bioreactors ; *Autotrophic Processes ; *Membranes, Artificial ; Biological Oxygen Demand Analysis ; Denitrification ; Bacteria/metabolism ; Nitrites/metabolism ; Nitrification ; Water Purification/methods ; }, abstract = {The partial nitritation-anammox process based on a membrane-aerated biofilm reactor (MABR) faces several challenges, such as difficulty in suppressing nitrite-oxidizing bacteria (NOB), excessive effluent nitrate, and ineffective synergy between denitrification and anammox bacteria. Therefore, a novel partitioned granular sludge coupling with MABR (G-MABR) was constructed. The chemical oxygen demand (COD) and nitrogen removal efficiency were 88.8 ± 1.8 %-92.6 ± 1.2 % and 88.8 ± 1.5 %-93.6 ± 0.7 %, respectively. The COD was mainly lowered in the lower granular sludge-zone, while nitrogen was removed in the upper MABR-zone. NOB was significantly suppressed in the MABR-zone due to competition for substrate with denitrifying bacteria and anammox bacteria. This partitioned configuration reduced the C/N ratio in the MABR-zone, thus facilitating autotrophic nitrogen removal. Both partial nitrification and denitrification provided nitrite for anammox bacteria in granular sludge, whereas partial nitrification mainly supplied nitrite to the anammox bacteria in membrane biofilms.}, }
@article {pmid39368567, year = {2024}, author = {Ofori, P and Zemliana, N and Zaffran, I and Etzion, T and Sionov, RV and Steinberg, D and Mechoulam, R and Kogan, NM and Levi-Schaffer, F}, title = {Antifungal properties of abnormal cannabinoid derivatives: Disruption of biofilm formation and gene expression in Candida species.}, journal = {Pharmacological research}, volume = {209}, number = {}, pages = {107441}, doi = {10.1016/j.phrs.2024.107441}, pmid = {39368567}, issn = {1096-1186}, mesh = {*Biofilms/drug effects/growth &amp; development ; Animals ; *Antifungal Agents/pharmacology/chemical synthesis/chemistry ; *Candida/drug effects/growth &amp; development ; Mice ; Candidiasis/drug therapy/microbiology ; Cannabinoids/pharmacology/chemistry ; Microbial Sensitivity Tests ; Male ; Gene Expression Regulation, Fungal/drug effects ; }, abstract = {Abnormal cannabinoids (including comp 3) are a class of synthetic lipid compounds with non-psychoactive properties and regioisomer configurations, but distinct from traditional cannabinoids since they do not interact with the established CB1 and CB2 receptors. Previous research showed the cardioprotective and anti-inflammatory potentials of comp 3 and more recently its antimicrobial effect on methicillin-resistant Staphylococcus aureus (MRSA). Given the escalating challenges posed by Candida infections and the rise of antifungal drug resistance, the exploration of novel therapeutic avenues is crucial. This study aimed to assess the anti-Candida properties of newly synthesized AbnCBD derivatives. AbnCBD derivatives were synthesized by acid catalysis-induced coupling and further derivatized. We evaluated the potential of the AbnCBD derivatives to inhibit the growth stages of various Candida species. By in vitro colorimetric assays and in vivo mice experiments, we have shown that AbnCBD derivatives induce differential inhibition of Candida growth. The AbnCBD derivatives, especially comp 3, comp 10, and comp 9 significantly reduced the growth of C. albicans, including FLC-resistant strains, and of C. tropicalis and C. parapsilosis but not of C auris compared to their controls (FLC and 0.5 % DMSO). Comp 3 also disrupted C. albicans biofilm formation and eradicated mature biofilms. Notably, other derivatives of AbnCBD disrupted the biofilm formation and maturation of C. albicans but did not affect yeast growth. In a murine model of VVC, comp 3 demonstrated significant fungal clearance and reduced C. albicans burden compared to vehicle and FLC controls. These findings highlight the potential of AbnCBDs as promising antifungal agents against Candida infections.}, }
@article {pmid39368563, year = {2024}, author = {Manna, T and Chandra Guchhait, K and Jana, D and Dey, S and Karmakar, M and Hazra, S and Manna, M and Jana, P and Panda, AK and Ghosh, C}, title = {Wastewater-based surveillance of Vibrio cholerae: Molecular insights on biofilm regulatory diguanylate cyclases, virulence factors and antibiotic resistance patterns.}, journal = {Microbial pathogenesis}, volume = {196}, number = {}, pages = {106995}, doi = {10.1016/j.micpath.2024.106995}, pmid = {39368563}, issn = {1096-1208}, mesh = {*Biofilms/growth &amp; development/drug effects ; *Virulence Factors/genetics ; *Vibrio cholerae/genetics/drug effects/pathogenicity ; India ; *Phosphorus-Oxygen Lyases/genetics/metabolism ; *Wastewater/microbiology ; *Bacterial Proteins/genetics/metabolism ; Cholera/microbiology ; Anti-Bacterial Agents/pharmacology ; Cyclic GMP/analogs &amp; derivatives/metabolism ; Microbial Sensitivity Tests ; Drug Resistance, Bacterial/genetics ; Gene Expression Regulation, Bacterial ; Escherichia coli Proteins ; }, abstract = {Vibrio cholerae is an inherent inhabitant of aquatic ecosystems. The Indian state of West Bengal, especially the Gangetic delta region is the highest cholera affected region and is considered as the hub of Asiatic cholera. V. cholerae were isolated from publicly accessible wastewater of Midnapore, West Bengal, India. Serotyping determined all isolates to be of non-O1/non-O139 serogroups. Moderate biofilm-forming abilities were noticed in most of the isolates (74.7 %) while, high biofilm formation was recorded for only 6.3 % isolates and 19 % of isolates exhibited low/non-biofilm-forming abilities. PCR-based screening of crucial diguanylate cyclases (DGCs) involved in cyclic-di-GMP-mediated biofilm signaling was performed. cdgH and cdgM were the most abundant DGCs among 93.7 % and 91.5 % of isolates, respectively. Other important DGCs, i.e., cdgK, cdgA, cdgL, and vpvC were present in 84 %, 75.5 %, 72 % and 68 % of isolates, respectively. Besides, the non-O1/non-O139 isolates were screened for the occurrence of virulence factor encoding genes. Moreover, among these non-O1/non-O139 isolates, two strains (3.17 %) harbored both ctxA and ctxB genes, which encode the cholera toxin associated with epidemic cholera. ompU was the most prevalent virulence factor, present in 24.8 % of isolates. Other virulence factors like, zot and st were found in 4.7 % and 9.5 % of isolates. Genes encoding tcp and ace were found to be PCR-negative for the isolates. Additionally, crucial virulence factor regulators, toxT, toxR and hapR were found to be PCR-positive in all the isolates. Antibiotic resistance patterns displayed further vulnerabilities with decreased sensitivity towards commonly used antibiotics with multiple antibiotic resistance index ranging between 0.37 and 0.62. The presence of cholera toxin-encoding multi-drug resistant (MDR) V. cholerae strains in environmental settings is alarming. High occurrence of DGCs are considered to encourage further investigations to use them as alternative therapeutic targets against MDR cholera pathogen due to their unique presence in bacterial systems.}, }
@article {pmid39367886, year = {2024}, author = {Zhang, J and Hao, J and Wang, J and Li, H and Zhao, D}, title = {Strategic manipulation of biofilm dispersion for controlling Listeria monocytogenes infections.}, journal = {Critical reviews in food science and nutrition}, volume = {}, number = {}, pages = {1-10}, doi = {10.1080/10408398.2024.2409340}, pmid = {39367886}, issn = {1549-7852}, abstract = {Listeria monocytogenes (L. monocytogenes), a gram-positive foodborne pathogen that can easily cause listeriosis. It secretes extracellular polymers and forms biofilms that are highly resistant to disinfection methods, such as UV light and germicides, posing risks to food processing equipment and food quality. Dispersion of biofilm is the cycle of its formation in which the bacteria return to planktonic state and become susceptible to antimicrobials, the strategic manipulation of biofilm dispersion is thus heralded as a novel and promising approach for the effective control of biofilm-related infections. Compared to the traditional methods, it is more effective to start with the composition of biofilms, cut off the production of their constituent substances, and genetically reduce the probability of biofilm formation. Meanwhile, the dispersion of bacteria can be supplemented with exogenous substances, making long-term control possible. This paper provides a brief but comprehensive overview of the mechanisms of L. monocytogenes biofilms or cross-contamination and their resistance properties, and facilitates our understanding and control of the prevention and containment of L. monocytogenes biofilm contamination based on the biofilm's active and passive diffusion strategies. This work provides practical guidelines for the food industry to guard against the enduring threat to food safety due to L. monocytogenes biofilms.}, }
@article {pmid39366290, year = {2024}, author = {Bundurus, IA and Balta, I and Pet, I and Stef, L and Popescu, CA and McCleery, D and Lemon, J and Callaway, T and Douglas, A and Corcionivoschi, N}, title = {Mechanistic concepts involved in biofilm associated processes of Campylobacter jejuni: persistence and inhibition in poultry environments.}, journal = {Poultry science}, volume = {103}, number = {12}, pages = {104328}, pmid = {39366290}, issn = {1525-3171}, mesh = {*Campylobacter jejuni/physiology/drug effects ; *Biofilms/drug effects ; Animals ; *Campylobacter Infections/veterinary/microbiology/prevention &amp; control ; *Poultry Diseases/microbiology/prevention &amp; control ; Poultry/microbiology ; Chickens ; }, abstract = {Campylobacter species, predominantly Campylobacter jejuni, remains a significant zoonotic pathogen worldwide, with the poultry sector being the primary vector for human transmission. In recent years. there has been a notable rise in the incidence of human campylobacteriosis, necessitating a deeper understanding of the pathogen's survival mechanisms and transmission dynamics. Biofilm presence significantly contributes to C. jejuni persistence in poultry and subsequent food product contamination, and this review describes the intricate processes involved in biofilm formation. The ability of Campylobacter to form biofilms on various surfaces, including stainless steel, plastic, and glass, is a critical survival strategy. Campylobacter biofilms, with their remarkable resilience, protect the pathogen from environmental stresses such as desiccation, pH extremes, biocides and sanitizing agents. This review explores the molecular and genetic mechanisms of C. jejuni biofilm formation, highlighting regulatory genes involved in motility, chemotaxis, and stress responses. Flagellar proteins, particularly flaA, flaB, flaG, and adhesins like cadF and flpA, are identified as the main molecular components in biofilm development. The role of mixed-species biofilms, where C. jejuni integrates into existing biofilms of other bacteria to enhance pathogen resilience, is also discussed. This review also considers alternative interventions to control C. jejuni in poultry production, in the context of increasing antibiotic resistance. It explores the effectiveness of prebiotics, probiotics, synbiotics, bacteriocins, bacteriophages, vaccines, and organic acids, with a focus on their mechanisms of action in reducing bacterial colonization and biofilm formation. Studies show that mixtures of organic acids and compounds like Carvacrol and Eugenol significantly downregulate genes linked with motility and adhesion, thereby disrupting biofilm integrity. It discusses the impact of environmental factors, such as temperature and oxygen levels on biofilm formation, providing insights into how industrial conditions can be manipulated to reduce contamination. This paper stresses the need for a multifaceted approach to control Campylobacter in poultry, integrating molecular and genetic insights with practical interventions. By advancing our understanding of biofilm dynamics and gene regulation, we aim to inform the development of more effective strategies to enhance food safety and protect public health.}, }
@article {pmid39367219, year = {2024}, author = {Battulga, B and Nakanishi, T and Atarashi-Andoh, M and Otosaka, S and Koarashi, J}, title = {Biofilm-mediated interactions between plastics and radiocesium in coastal environments.}, journal = {Environmental science and pollution research international}, volume = {31}, number = {50}, pages = {60080-60092}, pmid = {39367219}, issn = {1614-7499}, support = {23KK0201//Japan Society for the Promotion of Science/ ; }, mesh = {*Biofilms ; *Plastics ; *Cesium Radioisotopes ; Japan ; }, abstract = {A ubiquitous distribution of plastic debris has been reported in aquatic and terrestrial environments; however, the interactions between plastics and radionuclides and the radioactivity of environmental plastics remain largely unknown. Here, we characterize biofilms developing on the surface of plastic debris to explore the role of plastic-associated biofilms as an interaction medium between plastics and radiocesium ([137]Cs) in the environment. Biofilm samples were extracted from plastics (1-50 mm in size) collected from two contrasting coastal areas in Japan. The radioactivity of plastics was estimated based on the [137]Cs activity concentration of the biofilms and compared seasonally with surrounding environmental samples (i.e., sediment and sand). [137]Cs traces were detected in biofilms with activity concentrations of 21-1300 Bq·kg[-1] biofilm (dry weight), corresponding to 0.04-4.5 Bq·kg[-1] plastic (dry weight). Our results reveal the interaction between [137]Cs and plastics and provide evidence that organic and mineral components in biofilms are essential in [137]Cs retention in environmental plastics. Given the ubiquitous distribution of plastic debris in the environment, more attention should be directed to bioaccumulation and the radioecological impacts of plastic-associated radionuclides on ecosystems.}, }
@article {pmid39366990, year = {2024}, author = {Pappe, E and Hübner, RH and Saccomanno, J and Ebrahimi, HDN and Witzenrath, M and Wiessner, A and Sarbandi, K and Xiong, Z and Kursawe, L and Moter, A and Kikhney, J}, title = {Biofilm infections of endobronchial valves in COPD patients after endoscopic lung volume reduction: a pilot study with FISHseq.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {23078}, pmid = {39366990}, issn = {2045-2322}, mesh = {Humans ; *Biofilms/growth &amp; development ; Pilot Projects ; Male ; *Pulmonary Disease, Chronic Obstructive/microbiology ; Female ; Aged ; *In Situ Hybridization, Fluorescence ; Middle Aged ; Pneumonectomy/methods ; }, abstract = {Endoscopic lung volume reduction (ELVR) using endobronchial valves (EBV) is a treatment option for a subset of patients with severe chronic obstructive pulmonary disease (COPD), suffering from emphysema and hyperinflation. In this pilot study, we aimed to determine the presence of bacterial biofilm infections on EBV and investigate their involvement in lack of clinical benefits, worsening symptomatology, and increased exacerbations that lead to the decision to remove EBVs. We analyzed ten COPD patients with ELVR who underwent EBV removal. Clinical data were compared to the microbiological findings from conventional EBV culture. In addition, EBV were analyzed by FISHseq, a combination of Fluorescence in situ hybridization (FISH) with PCR and sequencing, for visualization and identification of microorganisms and biofilms. All ten patients presented with clinical symptoms, including pneumonia and recurrent exacerbations. Microbiological cultures from EBV detected several microorganisms in all ten patients. FISHseq showed either mixed or monospecies colonization on the EBV, including oropharyngeal bacterial flora, Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcus spp., and Fusobacterium sp. On 5/10 EBV, FISHseq visualized biofilms, on 1/10 microbial microcolonies, on 3/10 single microorganisms, and on 1/10 no microorganisms. The results of the study demonstrate the presence of biofilms on EBV for the first time and its potential involvement in increased exacerbations and clinical worsening in patients with ELVR. However, further prospective studies are needed to evaluate the clinical relevance of biofilm formation on EBV and appropriate treatment options to avoid infections in patients with ELVR.}, }
@article {pmid39363349, year = {2024}, author = {Ivers, C and Kaya, EC and Yucel, U and Boyle, D and Trinetta, V}, title = {Evaluation of Salmonella biofilm attachment and hydrophobicity characteristics on food contact surfaces.}, journal = {BMC microbiology}, volume = {24}, number = {1}, pages = {387}, pmid = {39363349}, issn = {1471-2180}, mesh = {*Biofilms/growth &amp; development ; *Hydrophobic and Hydrophilic Interactions ; *Salmonella/physiology/growth &amp; development ; *Bacterial Adhesion ; *Food Microbiology ; Surface Properties ; Microscopy, Confocal ; Food Contamination ; }, abstract = {Salmonella forms biofilms, and persist on food contact surfaces. Once a biofilm is formed cleaning and sanitation protocols may be inadequate for effective removal. This study evaluated attachment characteristics, surface properties, and structure of Salmonella biofilms on food contact surfaces commonly used in the tree-fruit industry. Multi-strain Salmonella biofilms were grown in a Centers for Disease Control and Prevention (CDC) biofilm reactor at 22 ± 2 °C and sampling was conducted at 2, 24 and 96-h. After each incubation period, coupons weregently rinsed and the remaining cells enumerated. Biofilms were analyzed with Laser Scanning Confocal Microscopy (LSCM). Hydrophobicity was evaluated by measuring the contact angles of reference liquids method using a drop tensiometer instrument. Material type and biofilm age significantly influenced attachment and biofilm hydrophobicity (P < 0.05). The strength of attachment, across all time points, was highest on nylon followed by wood and high-density polyethylene. The highest contact angle measurements were observed after 96-h of biofilm formation for each material. All the results and observations from this study contribute to a better understanding of the attachment and hydrophobicity characteristics of Salmonella and might help producers make informed decisions when selecting containers for harvesting and storing in order to minimize biofilm formation and potential for cross-contamination.}, }
@article {pmid39363239, year = {2024}, author = {Vatankhah, M and Mahboubi, A and Varshochian, R and Haeri, A and Houri, H and Abbasian, Z and Dadashzadeh, S}, title = {Thermosensitive multivesicular liposomal hydrogel: a potential platform for loco-regional drug delivery in the treatment of osteomyelitis caused by antibiotic-resistant biofilm-forming bacteria.}, journal = {Letters in applied microbiology}, volume = {77}, number = {10}, pages = {}, doi = {10.1093/lambio/ovae092}, pmid = {39363239}, issn = {1472-765X}, support = {32030//Shahid Beheshti University of Medical Sciences/ ; }, mesh = {*Biofilms/drug effects ; *Osteomyelitis/drug therapy/microbiology ; *Liposomes/chemistry ; *Anti-Bacterial Agents/pharmacology/administration &amp; dosage ; *Hydrogels/chemistry ; *Vancomycin/pharmacology/administration &amp; dosage ; *Drug Delivery Systems ; Staphylococcus aureus/drug effects ; Methicillin-Resistant Staphylococcus aureus/drug effects ; Humans ; Drug Liberation ; Poloxamer/chemistry ; Staphylococcal Infections/drug therapy/microbiology ; Microbial Sensitivity Tests ; }, abstract = {Biofilm-mediated osteomyelitis presents significant therapeutic challenges. Given the limitations of existing osteomyelitis treatment approaches, there is a distinct need to develop a localized drug delivery system that is biocompatible, biodegradable, and capable of controlled antibiotic release. Multivesicular liposomes (MVLs), characterized by their non-concentric vesicular structure, distinct composition, and enhanced stability, serve as the system for a robust sustained-release drug delivery platform. In this study, various hydrogel formulations composed of poloxamer 407 and other hydrogels, incorporating vancomycin hydrochloride (VAN HL)-loaded MVLs (VAN HL-MVLs), were prepared and evaluated. The optimized VAN HL-MVL sol-gel system, consisting of poloxamer 407 and hyaluronic acid, successfully maintained drug release for up to 3 weeks and exhibited shear-thinning behavior at 37°C. While complete drug release from MVLs alone took place in 312 h, the hydrogel formulation extended this release to 504 h. The released drug effectively inhibited the Staphylococcus aureus biofilms growth within 24 h and methicillin-resistant S. aureus biofilms within 72 h. It also eradicated preformed biofilms of S. aureus and methicillin-resistant S. aureus in 96 and 120 h, respectively. This injectable in situ gel system incorporating VAN HL-MVLs holds potential as an alternative to undergoing multiple surgeries for osteomyelitis treatment and warrants further studies.}, }
@article {pmid39362854, year = {2024}, author = {Kunisch, F and Campobasso, C and Wagemans, J and Yildirim, S and Chan, BK and Schaudinn, C and Lavigne, R and Turner, PE and Raschke, MJ and Trampuz, A and Gonzalez Moreno, M}, title = {Targeting Pseudomonas aeruginosa biofilm with an evolutionary trained bacteriophage cocktail exploiting phage resistance trade-offs.}, journal = {Nature communications}, volume = {15}, number = {1}, pages = {8572}, pmid = {39362854}, issn = {2041-1723}, support = {01KI1823//Bundesministerium f&#xfc;r Bildung und Forschung (Federal Ministry of Education and Research)/ ; }, mesh = {*Pseudomonas aeruginosa/virology/physiology/drug effects ; *Biofilms/growth &amp; development ; *Bacteriophages/physiology/genetics ; *Anti-Bacterial Agents/pharmacology ; Pseudomonas Phages/physiology/genetics ; Humans ; Phage Therapy/methods ; Drug Resistance, Multiple, Bacterial ; Pseudomonas Infections/therapy/microbiology ; Host Specificity ; Microbial Sensitivity Tests ; }, abstract = {Spread of multidrug-resistant Pseudomonas aeruginosa strains threatens to render currently available antibiotics obsolete, with limited prospects for the development of new antibiotics. Lytic bacteriophages, the viruses of bacteria, represent a path to combat this threat. In vitro-directed evolution is traditionally applied to expand the bacteriophage host range or increase bacterial suppression in planktonic cultures. However, while up to 80% of human microbial infections are biofilm-associated, research towards targeted improvement of bacteriophages' ability to combat biofilms remains scarce. This study aims at an in vitro biofilm evolution assay to improve multiple bacteriophage parameters in parallel and the optimisation of bacteriophage cocktail design by exploiting a bacterial bacteriophage resistance trade-off. The evolved bacteriophages show an expanded host spectrum, improved antimicrobial efficacy and enhanced antibiofilm performance, as assessed by isothermal microcalorimetry and quantitative polymerase chain reaction, respectively. Our two-phage cocktail reveals further improved antimicrobial efficacy without incurring dual-bacteriophage-resistance in treated bacteria. We anticipate this assay will allow a better understanding of phenotypic-genomic relationships in bacteriophages and enable the training of bacteriophages against other desired pathogens. This, in turn, will strengthen bacteriophage therapy as a treatment adjunct to improve clinical outcomes of multidrug-resistant bacterial infections.}, }
@article {pmid39362422, year = {2024}, author = {Bellich, B and Cacioppo, M and De Zorzi, R and Rizzo, R and Brady, JW and Cescutti, P}, title = {Interactions of biofilm polysaccharides produced by human infective bacteria with molecules of the quorum sensing system. A microscopy and NMR study.}, journal = {International journal of biological macromolecules}, volume = {281}, number = {Pt 2}, pages = {136222}, doi = {10.1016/j.ijbiomac.2024.136222}, pmid = {39362422}, issn = {1879-0003}, mesh = {*Quorum Sensing ; *Biofilms/growth &amp; development ; *Polysaccharides, Bacterial/chemistry/metabolism ; *Magnetic Resonance Spectroscopy/methods ; Humans ; Rhamnose/metabolism/chemistry ; Bacteria/metabolism ; }, abstract = {Biofilms are the most common lifestyle adopted by bacterial communities where cells live embedded in a self-produced hydrated matrix. Although polysaccharides are considered essential for matrix architecture, their possible functional roles are still rather unexplored. The primary structure of polysaccharides produced by Klebsiella pneumoniae and species of the Burkholderia cepacia Complex revealed a composition rich in rhamnose. The methyl group on carbon 6 of rhamnose units lowers the polymer hydrophilicity and can form low polarity regions on the polysaccharide chains. These regions promote chain-chain interactions that contribute to the biofilm matrix stability, but may also act as binding sites for low-polarity molecules, aiding their mobility through the hydrated matrix. In particular, quorum sensing system components crucial for the biofilm life cycle often display poor solubility in water. Therefore, cis-11-methyl-2-dodecenoic acid and L-homoserine-lactones were investigated by NMR spectroscopy for their possible interaction with polysaccharides. In addition, the macromolecular morphology of the polysaccharides was assessed using atomic force and electron microscopies to define the role of Rha residues on the three-dimensional conformation of the polymer. NMR data revealed that quorum sensing components interact with Rhamnose-rich polysaccharides, and the extent of interaction depends on the specific primary structure of each polysaccharide.}, }
@article {pmid39361487, year = {2024}, author = {Tahir, S and Parvin, F and Wang, M and Deva, AK and Vickery, K and Hu, H}, title = {The efficacy of antimicrobial solutions against multispecies bacterial biofilm with or without negative pressure wound therapy in an in vitro wound model.}, journal = {The Journal of antimicrobial chemotherapy}, volume = {79}, number = {12}, pages = {3178-3185}, doi = {10.1093/jac/dkae338}, pmid = {39361487}, issn = {1460-2091}, support = {//KCI Medical Australia Pty Ltd/ ; }, mesh = {*Biofilms/drug effects ; *Negative-Pressure Wound Therapy/methods ; Humans ; Microscopy, Electron, Scanning ; Wound Infection/microbiology/drug therapy ; Microscopy, Confocal ; Colony Count, Microbial ; In Situ Hybridization, Fluorescence ; Microbial Viability/drug effects ; Anti-Bacterial Agents/pharmacology ; Anti-Infective Agents/pharmacology ; Bacteria/drug effects ; Pseudomonas aeruginosa/drug effects ; }, abstract = {OBJECTIVES: Biofilm is the major challenge in chronic wound management. Instilling a wound cleansing solution aids in wound bed cleaning and infectious pathogen elimination. Negative pressure wound therapy (NPWT) improves the wound-healing process. This study investigated the efficacy of two antimicrobials (Vashe Wound Cleanser and Prontosan Wound Irrigation Solution) against a multispecies bacterial biofilm with or without NPWT in an in vitro wound model.<br><br>METHODS: A mixed multispecies biofilm containing Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcus pyogenes, and Acinetobacter baumannii was developed and verified by scanning electron microscopy and fluorescent in situ hybridization. The efficacy of Vashe and Prontosan against multispecies biofilm with or without NPWT was evaluated by colony-forming unit (cfu) of each species and total bacterial number, and visually confirmed by live/dead stain and confocal microscopy.<br><br>RESULTS: Prontosan reduced biofilm cell numbers significantly: 6 instils over 24&#x2005;h resulting in 3.86&#x200a;&#xb1;&#x200a;0.14&#x2005;cfu log10 reduction without NPWT and 4.75&#x200a;&#xb1;&#x200a;0.13&#x2005;cfu log10 reduction combined with NPWT (P&#x200a;<&#x200a;0.01) and 12 instils over 48&#x2005;h resulting in 5.24&#x200a;&#xb1;&#x200a;0.11&#x2005;cfu log10 reduction without NPWT and biofilm eradication with NPWT (P&#x200a;<&#x200a;0.001). NPWT alone or combined with Vashe failed to reduce multispecies biofilm numbers significantly over 24 or 48&#x2005;h.<br><br>CONCLUSIONS: Prontosan significantly reduced biofilm cell numbers, with better efficacy over 48 than 24&#x2005;h, emphasizing the necessity for persistent and robust treatment. NPWT enhanced the effectiveness of Prontosan instillation. However, NPWT alone or combined with Vashe showed limited efficacy and difficulty when combating the multispecies biofilm in vitro.}, }
@article {pmid39361981, year = {2024}, author = {Zhou, J and Ramasamy, P and Li, K}, title = {Corrigendum to "Chitosan-collagen biopolymer biofilm derived from cephalopod gladius; evaluation of osteogenesis, angiogenesis and wound healing for tissue engineering application" [Int. J. Biol. Macromol. 2024 Aug 26;279(Pt 1):135078].}, journal = {International journal of biological macromolecules}, volume = {281}, number = {Pt 1}, pages = {136104}, doi = {10.1016/j.ijbiomac.2024.136104}, pmid = {39361981}, issn = {1879-0003}, }
@article {pmid39361085, year = {2024}, author = {Hindieh, P and Yaghi, J and Assaf, JC and Chokr, A and Atoui, A and Louka, N and Khoury, AE}, title = {Unlocking the potential of lactic acid bacteria mature biofilm extracts as antibiofilm agents.}, journal = {AMB Express}, volume = {14}, number = {1}, pages = {112}, pmid = {39361085}, issn = {2191-0855}, abstract = {The continuous growth of biofilm infections and their resilience to conventional cleaning methods and antimicrobial agents pose a worldwide challenge across diverse sectors. This persistent medical, industrial, and environmental issue contributes to treatment challenges and chronic diseases. Lactic acid bacteria have garnered global attention for their substantial antimicrobial effects against pathogens and established beneficial roles. Notably, their biofilms are also predicted to show a promising control strategy against pathogenic biofilm formation. The prevalence of biofilm-related problems underscores the need for extensive research and innovative solutions to tackle this global challenge. This novel study investigates the effect of different extracts (external, internal, and mixed extracts) obtained from Lactobacillus rhamnosus GG biofilm on pathogenic-formed biofilms. Subsequently, external extracts presented an important eradication effectiveness. Furthermore, a 6-fold concentration of these extracts led to eradication percentages of 57%, 67%, and 76% for Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa biofilms, respectively, and around 99.9% bactericidal effect of biofilm cells was observed for the three strains. The results of this research could mark a significant breakthrough in the field of anti-biofilm and antimicrobial strategies. Further studies and molecular research will be necessary to detect the molecules secreted by the biofilm, and their mechanisms of action engaged in new anti-biofilm strategies.}, }
@article {pmid39360839, year = {2024}, author = {Gómez-Mejia, A and Orlietti, M and Tarnutzer, A and Mairpady Shambat, S and Zinkernagel, AS}, title = {Inhibition of Streptococcus pyogenes biofilm by Lactiplantibacillus plantarum and Lacticaseibacillus rhamnosus.}, journal = {mSphere}, volume = {9}, number = {10}, pages = {e0043024}, pmid = {39360839}, issn = {2379-5042}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Streptococcus pyogenes/drug effects/physiology/growth &amp; development ; *Lacticaseibacillus rhamnosus/physiology/drug effects ; *Lactobacillus plantarum/physiology/drug effects ; Probiotics/pharmacology ; Humans ; Antibiosis ; Microbial Viability/drug effects ; Anti-Bacterial Agents/pharmacology ; }, abstract = {The human pathobiont Streptococcus pyogenes forms biofilms and causes infections, such as pharyngotonsillitis and necrotizing fasciitis. Bacterial biofilms are more resilient to antibiotic treatment, and new therapeutic strategies are needed to control biofilm-associated infections, such as recurrent pharyngotonsillitis. Lactiplantibacillus plantarum and Lacticaseibacillus rhamnosus are two bacterial commensals used for their probiotic properties. This study aimed to elucidate the anti-biofilm properties of L. plantarum and L. rhamnosus cell-free supernatants (LPSN and LRSN, respectively) on S. pyogenes biofilms grown in vitro in supplemented minimal medium. When planktonic or biofilm S. pyogenes were exposed to LPSN or LRSN, S. pyogenes survival was reduced significantly in a concentration-dependent manner, and the effect was more pronounced on preformed biofilms. Enzymatic digestion of LPSN and LRSN suggested that glycolipid compounds might cause the antimicrobial effect. In conclusion, this study indicates that L. plantarum and L. rhamnosus produce glycolipid bioactive compounds that reduce the viability of S. pyogenes in planktonic and biofilm cultures.IMPORTANCEStreptococcus pyogenes infections are a significant concern for populations at risk, such as children and the elderly, as non-invasive conditions such as impetigo and strep throat can lead to severe invasive diseases such as necrotizing fasciitis. Despite its susceptibility to current antibiotics, the formation of biofilm by this pathogen decreases the efficacy of antibiotic treatment alone. The ability of commensal lactobacillus to kill S. pyogenes has been documented by previous studies using in vitro settings. The relevance of our study is in using a physiological setup and a more detailed understanding of the nature of the lactobacillus molecule affecting the viability of S. pyogenes. This additional knowledge will help for a better comprehension of the molecules' characteristics and kinetics, which in turn will facilitate new avenues of research for its translation to new therapies.}, }
@article {pmid39360709, year = {2024}, author = {Hu, R and Qian, H and Wang, X and Peng, B and Huang, D}, title = {Nicotine promotes pathogenic bacterial growth and biofilm formation in peri-implant.}, journal = {Journal of medical microbiology}, volume = {73}, number = {10}, pages = {}, doi = {10.1099/jmm.0.001897}, pmid = {39360709}, issn = {1473-5644}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Nicotine/pharmacology ; Humans ; *Peri-Implantitis/microbiology ; Fusobacterium nucleatum/drug effects/growth &amp; development/physiology ; Porphyromonas gingivalis/drug effects/growth &amp; development ; Male ; Dental Implants/microbiology ; Female ; Interleukin-6/metabolism ; Middle Aged ; Interleukins/metabolism ; Streptococcus sanguis/drug effects/growth &amp; development ; Bacteria/drug effects/classification/genetics/growth &amp; development/isolation &amp; purification ; Smoking/adverse effects ; }, abstract = {Introduction. Peri-implantitis is a plaque-associated disease that leads to implant loss and arises from bacterial biofilms on the surface of the implant. Smoking is a risk factor for peri-implantitis and impedes treatment effectiveness. Additionally, aryl hydrocarbon receptor (AHR), IL-6, and IL-22 levels are related to peri-implantitis.Aim. We aimed to investigate the effects of nicotine on inflammatory response, bacterial growth and biofilm formation.Hypothesis/Gap Statement. We hypothesized that nicotine promoted pathogenic bacterial growth and biofilm formation, thereby aggravating inflammation.Methodology. The expression of AHR, IL-6 and IL-22 was measured in peri-implant sulci fluid using quantitative PCR and Western blot analyses. The cementum was incubated with bacterial suspension including Porphyromonas gingivalis, Streptococcus sanguinis and Fusobacterium nucleatum and treated with 100, 200, 250 and 300 µg ml[-1] nicotine, and then, the absorbance and number of colony-forming units were detected. Biofilm formation was evaluated using the tissue culture plate method and safranin O staining. Carbohydrates and proteins were measured by the phenol-sulfuric acid method and the bicinchoninic acid method, respectively.Results. The results indicated that smoking increased the levels of AHR, IL-6 and IL-22. Functionally, nicotine promoted the growth of P. gingivalis, S. sanguinis and F. nucleatum. Additionally, it promoted the biofilm formation of these bacteria and increased the contents of carbohydrates and proteins.Conclusion. Nicotine promoted bacterial growth and biofilm build-up, suggesting that smoking may aggravate the progression of peri-implantitis.}, }
@article {pmid39359676, year = {2024}, author = {Wang, J and Yang, J and Durairaj, P and Wang, W and Wei, D and Tang, S and Liu, H and Wang, D and Jia, AQ}, title = {Discovery of β-nitrostyrene derivatives as potential quorum sensing inhibitors for biofilm inhibition and antivirulence factor therapeutics against Serratia marcescens.}, journal = {mLife}, volume = {3}, number = {3}, pages = {445-458}, pmid = {39359676}, issn = {2770-100X}, abstract = {Quorum sensing (QS) inhibition has emerged as a promising target for directed drug design, providing an appealing strategy for developing antimicrobials, particularly against infections caused by drug-resistant pathogens. In this study, we designed and synthesized a total of 33 β-nitrostyrene derivatives using 1-nitro-2-phenylethane (NPe) as the lead compound, to target the facultative anaerobic bacterial pathogen Serratia marcescens. The QS-inhibitory effects of these compounds were evaluated using S. marcescens NJ01 and the reporter strain Chromobacterium violaceum CV026. Among the 33 new β-nitrostyrene derivatives, (E)-1-methyl-4-(2-nitrovinyl)benzene (m-NPe, compound 28) was proven to be a potent inhibitor that reduced biofilm formation of S. marcescens NJ01 by 79%. Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) results revealed that treatment with m-NPe (50 μg/ml) not only enhanced the susceptibility of the formed biofilms but also disrupted the architecture of biofilms by 84%. m-NPe (50 μg/ml) decreased virulence factors in S. marcescens NJ01, reducing the activity of protease, prodigiosin, and extracellular polysaccharide (EPS) by 36%, 72%, and 52%, respectively. In S. marcescens 4547, the activities of hemolysin and EPS were reduced by 28% and 40%, respectively, outperforming the positive control, vanillic acid (VAN). The study also found that the expression levels of QS- and biofilm-related genes (flhD, fimA, fimC, sodB, bsmB, pigA, pigC, and shlA) were downregulated by 1.21- to 2.32-fold. Molecular dynamics analysis showed that m-NPe could bind stably to SmaR, RhlI, RhlR, LasR, and CviR proteins in a 0.1 M sodium chloride solution. Importantly, a microscale thermophoresis (MST) test revealed that SmaR could be a target protein for the screening of a quorum sensing inhibitor (QSI) against S. marcescens. Overall, this study highlights the efficacy of m-NPe in suppressing the virulence factors of S. marcescens, identifying it as a new potential QSI and antibiofilm agent capable of restoring or improving antimicrobial drug sensitivity.}, }
@article {pmid39358894, year = {2024}, author = {Gao, Y and Wang, J and Deng, Z and Wang, Y and Zhang, D and Xu, X and Yu, X and Wei, X}, title = {Targeted Delivery of 2D Composite Minerals for Biofilm Removal.}, journal = {ACS applied materials &amp; interfaces}, volume = {16}, number = {39}, pages = {52814-52823}, doi = {10.1021/acsami.4c10998}, pmid = {39358894}, issn = {1944-8252}, mesh = {*Biofilms/drug effects ; *Staphylococcus aureus/drug effects ; *Escherichia coli/drug effects ; Anti-Bacterial Agents/pharmacology/chemistry ; Chlorhexidine/pharmacology/chemistry ; Corrosion ; Magnetite Nanoparticles/chemistry ; Microbial Sensitivity Tests ; }, abstract = {Microbiologically influenced corrosion (MIC) poses considerable challenges in various industries, prompting the exploration of advanced materials to mitigate microbial threats. This study successfully synthesized nanoscale vermiculite (VMT) from natural seawater and utilized it as a foundation to integrate magnetic nanoparticles (Fe3O4) and chlorhexidine acetate (CA) for inhibiting MIC. A comprehensive investigation encompassing the synthesis, characterization, and application of these VMT/Fe3O4/CA composites was conducted to evaluate their antimicrobial effectiveness against Escherichia coli, Staphylococcus aureus, and sulfate-reducing bacteria (SRB), demonstrating an efficacy exceeding 99.5%. Moreover, the composite material demonstrated the capability to align with a magnetic field, enabling precise drug targeting and release, thereby facilitating biofilm removal. This research makes a significant contribution to the advancement of intelligent, efficient, and eco-friendly corrosion protection solutions.}, }
@article {pmid39358363, year = {2024}, author = {Valiei, A and Dickson, A and Aminian-Dehkordi, J and Mofrad, MRK}, title = {Metabolic interactions shape emergent biofilm structures in a conceptual model of gut mucosal bacterial communities.}, journal = {NPJ biofilms and microbiomes}, volume = {10}, number = {1}, pages = {99}, pmid = {39358363}, issn = {2055-5008}, mesh = {*Gastrointestinal Microbiome ; *Biofilms/growth &amp; development ; Humans ; *Bacteria/classification/metabolism/genetics ; *Microbial Interactions ; Computer Simulation ; Symbiosis ; Models, Biological ; Bacterial Physiological Phenomena ; Intestinal Mucosa/microbiology/metabolism ; }, abstract = {The gut microbiome plays a major role in human health; however, little is known about the structural arrangement of microbes and factors governing their distribution. In this work, we present an in silico agent-based model (ABM) to conceptually simulate the dynamics of gut mucosal bacterial communities. We explored how various types of metabolic interactions, including competition, neutralism, commensalism, and mutualism, affect community structure, through nutrient consumption and metabolite exchange. Results showed that, across scenarios with different initial species abundances, cross-feeding promotes species coexistence. Morphologically, competition and neutralism resulted in segregation, while mutualism and commensalism fostered high intermixing. In addition, cooperative relations resulted in community properties with little sensitivity to the selective uptake of metabolites produced by the host. Moreover, metabolic interactions strongly influenced colonization success following the invasion of newcomer species. These results provide important insights into the utility of ABM in deciphering complex microbiome patterns.}, }
@article {pmid39353484, year = {2024}, author = {Yu, G and Huang, TY and Li, Y}, title = {Kanamycin promotes biofilm viability of MRSA strains showing extremely high resistance to kanamycin.}, journal = {Microbial pathogenesis}, volume = {196}, number = {}, pages = {106986}, doi = {10.1016/j.micpath.2024.106986}, pmid = {39353484}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Methicillin-Resistant Staphylococcus aureus/drug effects/genetics ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; *Kanamycin/pharmacology ; Microbial Viability/drug effects ; Humans ; Drug Resistance, Bacterial ; Staphylococcal Infections/microbiology ; Bacterial Proteins/genetics/metabolism ; }, abstract = {Staphylococcus aureus is widely distributed in environment and can cause various human infection and food poisoning cases. Also, this pathogen is a typical biofilm former, which further complicates its pathogenicity. Antibiotics have been widely used to eliminate pathogenic bacteria, but their indiscriminate use has also led to the widespread emergence of drug-resistant bacteria, such as Methicillin-Resistant Staphylococcus aureus (MRSA). In this study, the effect of antibiotics on biofilm formation of MRSA strains 875 and 184 was explored. Firstly, MRSA 875 belongs to SCCmec type IV, ST239, carrying the atl, icaA, icaD, icaBC, and aap genes, and MRSA 184 belongs to SCCmec type II, ST5, carrying the atl, icaD, icaBC, aap, and agr genes. Then, a total of 8 antibiotics have been selected, including kanamycin, gentamycin, cipprofloxacin, erythromycin, meropenem, penicillin G, tetracycline, vancomycin. Minimum inhibitory concentrations (MICs) of each antibiotic were determined, and MIC of MRSA 875 and 184 to kanamycin/gentamicin are 2048/64 μg/mL and 2048/4 μg/mL, respectively. A total of 10 concentrations, ranging from 1/128 to 4 MIC with 2-fold, were used to study biofilm formation. Biofilm biomass and viability were determined during different phases, including initial adhesion (8 h), proliferation (16 h), accumulation (24 h) and maturation (48 h). Importantly, kanamycin at specific concentrations showed significant promotion of biofilm biomass and biofilm viability, with none of such observation acquired from other antibiotics. This study provides scientific basis and new research ideas for the quality control technology of microorganisms and safety prevention of MRSA.}, }
@article {pmid39353242, year = {2024}, author = {Ahmad, A and Al Senaidi, AS and Mubarak, MS}, title = {Microbial approach towards anode biofilm engineering enhances extracellular electron transfer for bioenergy production.}, journal = {Journal of environmental management}, volume = {370}, number = {}, pages = {122696}, doi = {10.1016/j.jenvman.2024.122696}, pmid = {39353242}, issn = {1095-8630}, mesh = {*Biofilms ; *Electrodes ; Bioelectric Energy Sources ; Electrolysis ; Electron Transport ; Sewage ; Electrons ; Bioreactors ; Electricity ; }, abstract = {Applying microbial electrolysis cells (MEC) is a biological approach to enhance the growth of high amounts of electroactive biofilm for extracellular electron transfer. The electroactive biofilm degrades the organics by oxidizing them at the anode and producing electrical energy. Addition of waste-activated sludge (WAS) with fat grease oil (FOG) produces an optimal reactor environment for microbial growth to enhance the exchange of electrons between cells via microbial electrolysis. The present work aimed to investigate the microbial approach to increase the extracellular electron transfer (EET) in microbial electrolysis cells. Results revealed that metabolites in electroactive microbes (EAM) grow viable cells that initiate high EET at anode sites. At optimum WAS with FOG addition, volatile fatty acid and current generation yield production was 2.94 ± 0.19 g/L and 17.91 ± 7.23 mA, accompanied by COD removal efficiency of 89.5 ± 14.4%, respectively. This study introduces a novel approach to anode biofilm engineering that significantly enhances extracellular electron transfer, offering a fresh perspective on bioenergy production. Our approach, which demonstrates that anodic biofilm enhances intercellular electron transfer, increases NADH-NAD ratio, and increases metabolite yield-fluxes, has the potential to revolutionize bio-electricity production. Results indicated that the electrolysis highlights MEC performance in power generation of 788 mV with 200 mL of anode volume of active viable cells by utilizing WAS with 11% FOG. The achievements of this study provide critical parameters for the anode biofilm engineering, demonstrating how growth cell volume, intercellular electron transfer, and increases in NADH-NAD ratio are evidence of an increase in the EET, compelling evidence for the resilience treatment and efficient current production. These findings are significant in advancing our understanding of bioenergy production.}, }
@article {pmid39352654, year = {2024}, author = {Ranđelović, M and Dimitrijević, M and Mijatović, S and Ignjatović, A and Arsić-Arsenijević, V and Stojanović-Radić, Z and Hay, R and Otašević, S}, title = {Antifungal susceptibility and biofilm production of Candida species- causative agents of female genital tract infections.}, journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]}, volume = {55}, number = {4}, pages = {3863-3872}, pmid = {39352654}, issn = {1678-4405}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Antifungal Agents/pharmacology ; Female ; Humans ; *Microbial Sensitivity Tests ; *Candida/drug effects/physiology/isolation &amp; purification/classification ; *Candidiasis, Vulvovaginal/microbiology ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ; Fluconazole/pharmacology ; }, abstract = {BACKGROUND: Recurrent vulvovaginal candidosis (RVVC) is a chronic infection affecting 8-10% of women worldwide. Biofilm production of the infecting species and reduced sensitivity to antimycotics could contribute to the recurrence of this infection. This study aimed to examine the biofilm production ability and antifungal susceptibility of genital yeast isolates to determine their virulence potential.<br><br>METHODS: Matrix-assisted laser desorption in ionization-time of flight mass spectrometry (MALDI-TOF MS) was used to identify 300 Candida species. Using crystal violet method, strains were categorized into non-producers, weak, moderate, and strong biofilm producers (BFP). Antifungal susceptibility testing was performed using commercial Integral System YEASTS Plus test (ISYPT) and broth microdilution method (BMM).<br><br>RESULTS: MALDI-TOF MS identified 150 Candida albicans, 124 non-albicans Candida (NAC), and 26 Saccharomyces cerevisiae strains. Within 138 (46.0%) BFP, 23 (16.7%) were strong, 44 (31.9%) moderate, and 71 (51.4%) weak. BMM was done for 43 BFP selected isolates with nystatin MIC &#x2c3;1.25 &#x3bc;l, fluconazole MIC &#x2c3;64 &#x3bc;l, and clotrimazole MIC &#x2c3;1.0 &#x3bc;l determined by ISYPT. Compared to all examined isolates, BMM confirmed that: i) C. albicans and NAC BFP showed low sensitivity to fluconazole (12% and 4%, respectively); ii) all BFP showed low sensitivity to nystatin (12.7% C. albicans, 14.5% NAC, and 23.1% S. cerevisiae); iii) clotrimazole in vitro was the most efficient regarding C. albicans and S. cerevisiae strains, but in 4.0% NAC BFP for this antimycotic higher MIC was established.<br><br>CONCLUSION: Novel antimycotics or possible combinations of antifungal agents and natural products could be a new treatment option for RVVC.}, }
@article {pmid39351665, year = {2024}, author = {Pradhan, L and Hazra, S and Singh, SV and Bajrang,  and Upadhyay, A and Pal, BN and Mukherjee, S}, title = {Correction: Surface modification of medical grade biomaterials by using a low-temperature-processed dual functional Ag-TiO2 coating for preventing biofilm formation.}, journal = {Journal of materials chemistry. B}, volume = {12}, number = {39}, pages = {10110}, doi = {10.1039/d4tb90157f}, pmid = {39351665}, issn = {2050-7518}, abstract = {Correction for 'Surface modification of medical grade biomaterials by using a low-temperature-processed dual functional Ag-TiO2 coating for preventing biofilm formation' by Lipi Pradhan et al., J. Mater. Chem. B, 2024, https://doi.org/10.1039/D4TB00701H.}, }
@article {pmid39351304, year = {2024}, author = {Elbakush, AM and Trunschke, O and Shafeeq, S and Römling, U and Gomelsky, M}, title = {Maple compounds prevent biofilm formation in Listeria monocytogenes via sortase inhibition.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1436476}, pmid = {39351304}, issn = {1664-302X}, abstract = {The Pss exopolysaccharide (EPS) enhances the ability of the foodborne pathogen Listeria monocytogenes to colonize and persist on surfaces of fresh fruits and vegetables. Eradicating listeria within EPS-rich biofilms is challenging due to their increased tolerance to disinfectants, desiccation, and other stressors. Recently, we discovered that extracts of maple wood, including maple sap, are a potent source of antibiofilm agents. Maple lignans, such as nortrachelogenin-8'-O-β-D-glucopyranoside and lariciresinol, were found to inhibit the formation of, and promote the dispersion of pre-formed L. monocytogenes EPS biofilms. However, the mechanism remained unknown. Here, we report that these lignans do not affect Pss EPS synthesis or degradation. Instead, they promote EPS detachment, likely by interfering with an unidentified lectin that keeps EPS attached to the cell surfaces. Furthermore, the maple lignans inhibit the activity of L. monocytogenes sortase A (SrtA) in vitro. SrtA is a transpeptidase that covalently anchors surface proteins, including the Pss-specific lectin, to the cell wall peptidoglycan. Consistent with this, deletion of the srtA gene results in Pss EPS detachment from listerial cells. We also identified several additional maple compounds, including epicatechin gallate, isoscopoletin, scopoletin, and abscisic acid, which inhibit L. monocytogenes SrtA activity in vitro and prevent biofilm formation. Molecular modelling indicates that, despite their structural diversity, these compounds preferentially bind to the SrtA active site. Since maple products are abundant and safe for consumption, our finding that they prevent biofilm formation in L. monocytogenes offers a viable source for protecting fresh produce from this foodborne pathogen.}, }
@article {pmid39350533, year = {2025}, author = {Ge, M and Zhu, W and Mei, J and Hu, T and Yang, C and Lin, H and Shi, J}, title = {Piezoelectric-Enhanced Nanocatalysts Trigger Neutrophil N1 Polarization against Bacterial Biofilm by Disrupting Redox Homeostasis.}, journal = {Advanced materials (Deerfield Beach, Fla.)}, volume = {37}, number = {6}, pages = {e2409633}, doi = {10.1002/adma.202409633}, pmid = {39350533}, issn = {1521-4095}, support = {2022YFB3804500//National Key R&amp;D Program of China/ ; JCYJ-SHFY-2022-003//Shanghai Pilot Program for Basic Research-Chinese Academy of Science/ ; 52372276//National Natural Science Foundation of China/ ; 82302717//National Natural Science Foundation of China/ ; 22335006//National Natural Science Foundation of China/ ; 21JC1406000//Basic Research Program of Shanghai Municipal Government/ ; 2023262//Youth Innovation Promotion Association of the Chinese Academy of Sciences/ ; //Young Elite Scientists Sponsorship Program by CAST/ ; 22QA1410200//Shanghai Science and Technology Committee Rising-Star Program/ ; 23ZR1472300//Natural Science Foundation of Shanghai/ ; 2021-I2M-5-012//CAMS Innovation Fund for Medical Sciences/ ; 23YF1432200//Shanghai Sailing Program/ ; 2023M732310//China Postdoctoral Science Foundation/ ; }, mesh = {Animals ; *Neutrophils/drug effects/metabolism ; *Biofilms/drug effects ; *Oxidation-Reduction ; Mice ; *Homeostasis/drug effects ; *Metal-Organic Frameworks/chemistry/pharmacology ; *Reactive Oxygen Species/metabolism ; *Nanoparticles/chemistry ; Catalysis ; Anti-Bacterial Agents/pharmacology/chemistry ; }, abstract = {Strategies of manipulating redox signaling molecules to inhibit or activate immune signals have revolutionized therapeutics involving reactive oxygen species (ROS). However, certain diseases with dual resistance barriers to the attacks by both ROS and immune cells, such as bacterial biofilm infections of medical implants, are difficult to eradicate by a single exogenous oxidative stimulus due to the diversity and complexity of the redox species involved. Here, this work demonstrates that metal-organic framework (MOF) nanoparticles capable of disrupting the bacterial ROS-defense system can dismantle bacterial redox resistance and induce potent antimicrobial immune responses in a mouse model of surgical implant infection by simultaneously modulating redox homeostasis and initiating neutrophil N1 polarization in the infection microenvironment. Mechanistically, the piezoelectrically enhanced MOF triggers ROS production by tilting the band structure and acts synergistically with the aurintricarboxylic acid loaded within the MOF, which inhibits the activity of the cystathionine γ-cleaving enzyme. This leads to biofilm structure disruption and antigen exposure through homeostatic imbalance and synergistic activation of neutrophil N1 polarization signals. Thus, this study provides an alternative but promising strategy for the treatment of antibiotic-resistant biofilm infections.}, }
@article {pmid39350452, year = {2024}, author = {Liu, Z and Wang, J and Qi, L and Wang, J and Xu, H and Yang, H and Liu, J and Liu, L and Feng, G and Zhang, L}, title = {Amino Acid Functionalized SrTiO3 Nanoarrays with Enhanced Osseointegration Through Programmed Rapid Biofilm Elimination and Angiogenesis Controlled by NIR-Driven Gas Therapy.}, journal = {Small (Weinheim an der Bergstrasse, Germany)}, volume = {20}, number = {51}, pages = {e2407078}, doi = {10.1002/smll.202407078}, pmid = {39350452}, issn = {1613-6829}, support = {82072546//National Natural Science Foundation of China/ ; 82272434//National Natural Science Foundation of China/ ; 2024YFHZ0304//Sichuan Science and Technology Program/ ; 2022ZDZX0029//Sichuan Science and Technology Program/ ; }, mesh = {*Titanium/chemistry/pharmacology ; *Biofilms/drug effects ; *Osseointegration/drug effects ; *Strontium/chemistry/pharmacology ; Animals ; *Infrared Rays ; Neovascularization, Physiologic/drug effects ; Oxides/chemistry/pharmacology ; Nitric Oxide/metabolism/chemistry ; Indocyanine Green/chemistry/pharmacology ; Mice ; Indoles/chemistry/pharmacology ; Angiogenesis ; Polymers ; }, abstract = {Bacterial biofilm formation is closely associated with persistent infections of medical implants, which can lead to implantation failure. Additionally, the reconstruction of the vascular network is crucial for achieving efficient osseointegration. Herein, an anti-biofilm nanoplatform based on L-arginine (LA)/new indocyanine green (NICG) that is anchored to strontim titanium oxide (SrTiO3) nano-arrays on a titanium (Ti) substrate by introducing polydopamine (PDA) serving as the interlayer is designed and successfully fabricated. Near-infrared light (NIR) is used to excite NICG, generating reactive oxygen species (ROS) that react with LA to release nitric oxide (NO) molecules. Utilizing the concentration-dependent effect of NO, high power density NIR irradiation applied during the early stage after implantation to release a high concentration of NO, which synergized with the photothermal effect of PDA to eliminate bacterial biofilm. Subsequently, the irradiation power density can be finely down-regulated to reduce the NO concentration in subsequent treatment for accelerating the reconstruction of blood vessels. Meanwhile, SrTiO3 nano-arrays improve the hydrophilicity of the implant surface and slowly release strontium (Sr) ions for continuously optimizing the osteogenic microenvironment. Effective biofilm elimination and revascularization alongside the continuous optimization of the osteogenic microenvironment can significantly enhance the osseointegration of the functionalized Ti implant in in vivo animal experiments.}, }
@article {pmid39350011, year = {2024}, author = {Tölken, LA and Neufend, JV and Oppegaard, O and Methling, K and Moll, K and Redanz, S and Katsburg, MMD and Ali, MQ and Shumba, P and Kreikemeyer, B and Skrede, S and Fulde, M and Norrby-Teglund, A and Lalk, M and Kittang, BR and Siemens, N}, title = {Streptokinase reduces Streptococcus dysgalactiae subsp. equisimilis biofilm formation.}, journal = {BMC microbiology}, volume = {24}, number = {1}, pages = {378}, pmid = {39350011}, issn = {1471-2180}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Streptokinase/genetics/metabolism ; *Streptococcus/genetics/drug effects/physiology ; Humans ; *Streptococcal Infections/microbiology ; Soft Tissue Infections/microbiology ; Bacterial Proteins/genetics/metabolism ; }, abstract = {BACKGROUND: Streptococcus dysgalactiae subspecies equisimilis (SDSE) is increasingly recognized as an emerging cause of invasive diseases including necrotizing soft tissue infections (NSTIs). In contrast to the closely related Streptococcus pyogenes, SDSE infections mainly affect older and comorbid patients. Biofilm formation has been demonstrated in soft tissue biopsies of S. pyogenes NSTI cases.<br><br>RESULTS: Here, we show that bacterial aggregations indicative of biofilms are also present in SDSE NSTI. Although streptokinase (Ska) activity and biofilm formation did not correlate in a diverse set of clinical SDSE isolates, addition of exogenous Ska at an early time point prevented biofilm formation for selected strains. Deletion of ska in SDSE S118 strain resulted in increased biofilm forming capacity. Ska-deficient mutant strain was characterized by a higher metabolic activity and consequent metabolome profiling of biofilms identified higher deposition of a wide range of metabolites as compared to the wild-type.<br><br>CONCLUSIONS: Our results argue that Ska suppresses biofilm formation in SDSE independent of its original plasminogen converting activity. However, the impact of biofilms and its consequences for patient outcomes in streptococcal NSTIs remain to be elucidated.}, }
@article {pmid39349970, year = {2024}, author = {Liu, X and Zou, L and Li, B and Di Martino, P and Rittschof, D and Yang, JL and Maki, J and Liu, W and Gu, JD}, title = {Chemical signaling in biofilm-mediated biofouling.}, journal = {Nature chemical biology}, volume = {20}, number = {11}, pages = {1406-1419}, pmid = {39349970}, issn = {1552-4469}, support = {32100101//National Natural Science Foundation of China (National Science Foundation of China)/ ; 32370105//National Natural Science Foundation of China (National Science Foundation of China)/ ; 92051103//National Natural Science Foundation of China (National Science Foundation of China)/ ; 31970036//National Natural Science Foundation of China (National Science Foundation of China)/ ; }, mesh = {*Biofilms/growth &amp; development/drug effects ; *Biofouling/prevention &amp; control ; *Quorum Sensing ; *Signal Transduction ; Animals ; }, abstract = {Biofouling is the undesirable accumulation of living organisms and their metabolites on submerged surfaces. Biofouling begins with adhesion of biomacromolecules and/or microorganisms and can lead to the subsequent formation of biofilms that are predominantly regulated by chemical signals, such as cyclic dinucleotides and quorum-sensing molecules. Biofilms typically release chemical cues that recruit or repel other invertebrate larvae and algal spores. As such, harnessing the biochemical mechanisms involved is a promising avenue for controlling biofouling. Here, we discuss how chemical signaling affects biofilm formation and dispersion in model species. We also examine how this translates to marine biofouling. Both inductive and inhibitory effects of chemical cues from biofilms on macrofouling are also discussed. Finally, we outline promising mitigation strategies by targeting chemical signaling to foster biofilm dispersion or inhibit biofouling.}, }
@article {pmid39349472, year = {2024}, author = {Davignon, G and Pietrosemoli, N and Benaroudj, N and Soupé-Gilbert, ME and Cagliero, J and Turc, &#xc9; and Picardeau, M and Guentas, L and Goarant, C and Thibeaux, R}, title = {Leptospira interrogans biofilm transcriptome highlights adaption to starvation and general stress while maintaining virulence.}, journal = {NPJ biofilms and microbiomes}, volume = {10}, number = {1}, pages = {95}, pmid = {39349472}, issn = {2055-5008}, mesh = {*Biofilms/growth &amp; development ; *Leptospira interrogans/genetics/pathogenicity ; Virulence ; *Transcriptome ; Animals ; *Leptospirosis/microbiology ; *Stress, Physiological ; *Gene Expression Regulation, Bacterial ; *Adaptation, Physiological/genetics ; Mice ; Gene Expression Profiling ; Disease Models, Animal ; }, abstract = {Life-threatening Leptospira interrogans navigate a dual existence: surviving in the environment and infecting mammalian hosts. Biofilm formation is presumably an important survival strategy to achieve this process. Understanding the relation between biofilm and virulence might improve our comprehension of leptospirosis epidemiology. Our study focused on elucidating Leptospira's adaptations and regulations involved in such complex microenvironments. To determine the transcriptional profile of Leptospira in biofilm, we compared the transcriptomes in late biofilms and in exponential planktonic cultures. While genes for motility, energy production, and metabolism were downregulated, those governing general stress response, defense against metal stress, and redox homeostasis showed a significant upsurge, hinting at a tailored defensive strategy against stress. Further, despite a reduced metabolic state, biofilm disruption swiftly restored metabolic activity. Crucially, bacteria in late biofilms or resulting from biofilm disruption retained virulence in an animal model. In summary, our study highlights Leptospira's adaptive equilibrium in biofilms: minimizing energy expenditure, potentially aiding in withstanding stresses while maintaining pathogenicity. These insights are important for explaining the survival strategies of Leptospira, revealing that a biofilm lifestyle may confer an advantage in maintaining virulence, an understanding essential for managing leptospirosis across both environmental and mammalian reservoirs.}, }
@article {pmid39349363, year = {2024}, author = {Zeng, T and Liu, J and Wah Cheung, C and Li, Y and Jia, H and Ming Tse, EC and Li, Y}, title = {Manganese Complex-Gold Nanoparticle Hybrid for Biofilm Inhibition and Eradication.}, journal = {Chembiochem : a European journal of chemical biology}, volume = {25}, number = {23}, pages = {e202400500}, doi = {10.1002/cbic.202400500}, pmid = {39349363}, issn = {1439-7633}, support = {17318422//Hong Kong Research Grants Council/ ; 22107088//National Science Fund of China/ ; }, mesh = {*Biofilms/drug effects ; *Gold/chemistry/pharmacology ; *Metal Nanoparticles/chemistry ; *Pseudomonas aeruginosa/drug effects ; *Manganese/chemistry/pharmacology ; *Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; Microbial Sensitivity Tests ; Reactive Oxygen Species/metabolism ; Coordination Complexes/chemistry/pharmacology/chemical synthesis ; }, abstract = {Biofilms, which are resistant to conventional antimicrobial treatments, pose significant challenges in medical and industrial environments. This study introduces manganese complex-gold nanoparticles (Mn-DPA-AuNPs) as a hybrid strategy for biofilm inhibition and eradication. Upon exposure to green light, these nanoparticles significantly enhance the generation of reactive oxygen species (ROS), including hydrogen peroxide and superoxide. This activity substantially reduces the regrowth potential of the surviving bacteria within the biofilm, with marked efficacy noted in Pseudomonas aeruginosa PAO1. This study highlights the potential of integrating manganese complexes with gold nanoparticles to develop advanced antimicrobial agents against resistant biofilms, offering a promising approach to enhance microbial control in diverse settings.}, }
@article {pmid39347874, year = {2024}, author = {Yoon, JY and Park, S and Lee, D and Park, OJ and Lee, W and Han, SH}, title = {Lipoteichoic Acid from Lacticaseibacillus rhamnosus GG as a Novel Intracanal Medicament Targeting Enterococcus faecalis Biofilm Formation.}, journal = {Journal of microbiology (Seoul, Korea)}, volume = {62}, number = {10}, pages = {897-905}, pmid = {39347874}, issn = {1976-3794}, support = {NRF-2018R1A5A2024418//National Research Foundation of Korea/ ; NRF-2022M3A9F3082330//National Research Foundation of Korea/ ; RS-2022-00164722//National Research Foundation of Korea/ ; 02-2023-0039//Seoul National University Bundang Hospital (SNUBH) Research Fund/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Enterococcus faecalis/drug effects/physiology/growth &amp; development ; *Teichoic Acids/metabolism ; Humans ; *Dental Pulp Cavity/microbiology ; *Lipopolysaccharides/metabolism ; *Lacticaseibacillus rhamnosus/drug effects/physiology ; Anti-Bacterial Agents/pharmacology ; Microscopy, Electron, Scanning ; Periapical Periodontitis/microbiology ; Root Canal Irrigants/pharmacology ; }, abstract = {The demand for safe and effective endodontic medicaments to control Enterococcus faecalis biofilms, a contributor to apical periodontitis, is increasing. Recently, lipoteichoic acid (LTA) of family Lactobacillaceae has been shown to have anti-biofilm effects against various oral pathogens. Preliminary experiments showed that LTA purified from Lacticaseibacillus rhamnosus GG (Lgg.LTA) was the most effective against E. faecalis biofilms among LTAs from three Lactobacillaceae including L. rhamnosus GG, Lacticaseibacillus casei, and Lactobacillus acidophilus. Therefore, in this study, we investigated the potential of Lgg.LTA as an intracanal medicament in human root canals infected with E. faecalis. Twenty eight dentinal cylinders were prepared from extracted human teeth, where two-week-old E. faecalis biofilms were formed followed by intracanal treatment with sterile distilled water (SDW), N-2 methyl pyrrolidone (NMP), calcium hydroxide (CH), or Lgg.LTA. Bacteria and biofilms that formed in the root canals were analyzed by scanning electron microscopy and confocal laser scanning microscopy. The remaining E. faecalis cells in the root canals after intracanal medicament treatment were enumerated by culturing and counting. When applied to intracanal biofilms, Lgg.LTA effectively inhibited E. faecalis biofilm formation as much as CH, while SDW and NMP had little effect. Furthermore, Lgg.LTA reduced both live and dead bacteria within the dentinal tubules, indicating the possibility of minimal re-infection in the root canals. Collectively, intracanal application of Lgg.LTA effectively inhibited E. faecalis biofilm formation, implying that Lgg.LTA can be used as a novel endodontic medicament.}, }
@article {pmid39347863, year = {2024}, author = {Klempt, F and Soleimani, M and Wriggers, P and Junker, P}, title = {A Hamilton principle-based model for diffusion-driven biofilm growth.}, journal = {Biomechanics and modeling in mechanobiology}, volume = {23}, number = {6}, pages = {2091-2113}, pmid = {39347863}, issn = {1617-7940}, support = {426335750//Deutsche Forschungsgemeinschaft,Germany/ ; }, mesh = {*Biofilms/growth &amp; development ; *Models, Biological ; Diffusion ; *Computer Simulation ; Stress, Mechanical ; }, abstract = {Dense communities of bacteria, also known as biofilms, are ubiquitous in all of our everyday life. They are not only always surrounding us, but are also active inside our bodies, for example in the oral cavity. While some biofilms are beneficial or even necessary for human life, others can be harmful. Therefore, it is highly important to gain an in-depth understanding of biofilms which can be achieved by in vitro or in vivo experiments. Since these experiments are often time-consuming or expensive, in silico models have proven themselves to be a viable tool in assisting the description and analysis of these complicated processes. Current biofilm growth simulations are using mainly two approaches for describing the underlying models. The volumetric approach splits the deformation tensor into a growth and an elastic part. In this approach, the mass never changes, unless some additional constraints are enforced. The density-based approach, on the other hand, uses an evolution equation to update the growing tissue by adding mass. Here, the density stays constant, and no pressure is exerted. The in silico model presented in this work combines the two approaches. Thus, it is possible to capture stresses inside of the biofilm while adding mass. Since this approach is directly derived from Hamilton's principle, it fulfills the first and second law of thermodynamics automatically, which other models need to be checked for separately. In this work, we show the derivation of the model as well as some selected numerical experiments. The numerical experiments show a good phenomenological agreement with what is to be expected from a growing biofilm. The numerical behavior is stable, and we are thus capable of solving complicated boundary value problems. In addition, the model is very reactive to different input parameters, thereby different behavior of various biofilms can be captured without modifying the model.}, }
@article {pmid39346024, year = {2024}, author = {Gao, X and Wang, H and Wu, Z and Sun, P and Yu, W and Chen, D and Mao, Y and Fang, L and Qian, J and Li, L and Peng, Q and Han, Y}, title = {The Characteristic of Biofilm Formation in ESBL-Producing K. pneumoniae Isolates.}, journal = {The Canadian journal of infectious diseases &amp; medical microbiology = Journal canadien des maladies infectieuses et de la microbiologie medicale}, volume = {2024}, number = {}, pages = {1802115}, pmid = {39346024}, issn = {1712-9532}, abstract = {Klebsiella pneumoniae is a pathogen that commonly causes hospital-acquired infections. Bacterial biofilms are structured bacterial communities that adhere to the surface of objects or biological tissues. In this study, we investigated the genome homology and biofilm formation capacity of ESBL-producing K. pneumoniae. Thirty ESBL-producing K. pneumoniae isolates from 25 inpatients at Ruijin Hospital, Shanghai, were subjected to pulsed-field gel electrophoresis (PFGE) to estimate genomic relatedness. Based on the chromosomal DNA patterns we obtained, we identified 21 PFGE profiles from the 30 isolates, eight of which had high homology indicating that they may have genetic relationships and/or potential clonal advantages within the hospital. Approximately 84% (21/25) of the clinical patients had a history of surgery, urinary tract catheterization, and/or arteriovenous intubation, all of which may have increased the risk for nosocomial infections. Biofilms were observed in 73% (22/30) of the isolates and that strains did not express type 3 fimbriae did not have biofilm formation capacity. Above findings indicated that a high percentage of ESBL-producing K. pneumoniae isolates formed biofilms in vitro and even though two strains with cut-off of PFGE reached 100% similarity, they generated biofilms differently. Besides, the variability in biofilm formation ability may be correlated with the expression of type 3 fimbriae. Thus, we next screened four ESBL-producing K. pneumoniae isolates (Kpn5, Kpn7, Kpn11, and Kpn16) with high homology and significant differences in biofilm formation using PFGE molecular typing, colony morphology, and crystal violet tests. Kpn7 and Kpn16 had stronger biofilm formation abilities compared with Kpn5 and Kpn11. The ability of above four ESBL-producing K. pneumoniae isolates to agglutinate in a mannose-resistant manner or in a mannose-sensitive manner, as well as RNA sequencing-based transcriptome results, showed that type 3 fimbriae play a significant role in biofilm formation. In contrast, type 1 fimbriae were downregulated during biofilm formation. Further research is needed to fully understand the regulatory mechanisms which underlie these processes.}, }
@article {pmid39346023, year = {2024}, author = {Soltan Dallal, MM and Nasser, A and Karimaei, S}, title = {Characterization of Virulence Genotypes, Antimicrobial Resistance Patterns, and Biofilm Synthesis in Salmonella spp Isolated from Foodborne Outbreaks.}, journal = {The Canadian journal of infectious diseases &amp; medical microbiology = Journal canadien des maladies infectieuses et de la microbiologie medicale}, volume = {2024}, number = {}, pages = {4805228}, pmid = {39346023}, issn = {1712-9532}, abstract = {Salmonella is the main bacterial pathogen that causes foodborne disease, particularly in developing countries. Nontyphoidal Salmonella (NTS) include Enteritidis and Typhimurium as the most prevalent strains which are one of the significant causes of acute gastroenteritis in children. Therefore, identifying the most predominant serovars, types of common contaminated food, and paying attention to their antibiotic resistance are the main factors in the prevention and control strategy of salmonellosis. This study was undertaken to evaluate the prevalence rate of serovars, the biofilm formation, antimicrobial resistance (AMR) status, and phenotypic virulence factors of Salmonella strains isolated from diarrhea samples in some cities of Iran. A total of 40 (10.41%) Salmonella isolates were recovered from 384 diarrhea samples processed and the most common serovar was Salmonella serovar Typhimurium (82.5). Also, all isolates belonging to serovar Typhimurium showed more virulence factors compared to other serovars. The isolates showed a high resistance rate to ampicillin (95%) and nalidixic acid (87.5%), while a low resistance rate was found for chloramphenicol (2.5%). Moreover, significant variances in the capacity of biofilm formation were found between different Salmonella serotypes. The resistance of NTS to extant choice drugs is a potential public health problem. Constant monitoring of AMR pattern and virulence profile of NTS serovars is suggested for the prevention of salmonellosis in humans.}, }
@article {pmid39345232, year = {2024}, author = {Veach, AM and Steinbrecher, A and Le, M}, title = {Spatial variability of bacterial biofilm communities in a wastewater effluent-impacted suburban stream ecosystem.}, journal = {Microbiology spectrum}, volume = {12}, number = {11}, pages = {e0424623}, pmid = {39345232}, issn = {2165-0497}, mesh = {*Wastewater/microbiology ; *Biofilms/growth &amp; development ; *Bacteria/genetics/classification/isolation &amp; purification/metabolism ; *Rivers/microbiology/chemistry ; *Microbiota ; *Ecosystem ; Archaea/classification/genetics/metabolism/isolation &amp; purification ; Biodiversity ; Phosphorus/analysis/metabolism ; RNA, Ribosomal, 16S/genetics ; Nitrogen/metabolism/analysis ; Biomass ; }, abstract = {UNLABELLED: Wastewater discharge is a global threat to freshwater resources. Streams, in particular, are receiving waterbodies that are directly impacted chemically and biologically due to effluent discharge. However, it is largely unknown how wastewater serves as a subsidy or a stressor to aquatic biodiversity, particularly microbiota, over space. Nutrient-diffusing substrata (NDS) were deployed; NDS release nutrients through diffusion into the water column into a wastewater-dependent stream across three reaches. We used N, P, and N + P treatments for the measurement of single nutrient and co-nutrient limitation, and a no-nutrient control. Both algal and total biofilm biomass was measured and the 16S ribosomal RNA genes via targeted amplicon sequencing was used to assess bacterial/archaeal community diversity. Data indicated that total organic matter in biofilms differs spatially with the greatest organic matter (OM) concentrations in the confluence downstream of wastewater inputs. Biofilm OM concentrations were greatest in P and N + P treatments in the confluence site relative to control or N-only treatments. This indicates heterotrophic microbial communities-likely bacteria that dominate stream biofilms-are P-limited in this ecosystem even with upstream wastewater inputs. In conjunction, bacteria/archaeal communities differed the greatest among nutrient treatments versus spatially and had several indicator taxa belonging to Flavobacterium spp. in N treatments relative to controls. Collectively with historical water quality data, we conclude that this wastewater-fed stream is primarily N-enriched but potentially P-limited, which results in significant shifts in biofilm bacterial communities and likely their overall biomass in this urban watershed.<br><br>IMPORTANCE: Streams in arid and semi-arid biomes are often dependent on their flow from municipal sources, such as wastewater effluent. However, wastewater has been shown to contain high concentrations of nutrients and chemical pollutants that can potentially harm aquatic ecosystems and their biota. Understanding if and the type of microorganisms that respond to pollution sources, specifically effluent from wastewater treatment facilities, in regions where flow is predominantly from treatment facilities, is critical for developing a predictive monitoring approach for eutrophication or other ecological degradation states for freshwaters.}, }
@article {pmid39345197, year = {2024}, author = {Wei, Y and Zhang, Y and Zhuang, Y and Tang, Y and Nie, H and Haung, Y and Liu, T and Yang, W and Yan, F and Zhu, Y}, title = {Veillonella parvula acts as a pathobiont promoting the biofilm virulence and cariogenicity of Streptococcus mutans in adult severe caries.}, journal = {Microbiology spectrum}, volume = {12}, number = {11}, pages = {e0431823}, pmid = {39345197}, issn = {2165-0497}, support = {82201055//MOST | National Natural Science Foundation of China (NSFC)/ ; 0223A205//2015 cultivation program for reserve talents for academic leaders of Nanjing Stomatological Hospital/ ; 2022-R-203 0222C116//3456 cultivation program for junior talents of Nanjing Stomatological Hospital/ ; ZKX23053//Nanjing Medical Science and Technique Development Foundation/ ; }, mesh = {*Biofilms/growth &amp; development ; *Streptococcus mutans/genetics/pathogenicity/physiology ; *Dental Caries/microbiology ; *Dental Plaque/microbiology ; Humans ; Virulence ; Animals ; Adult ; *Veillonella/genetics/physiology/pathogenicity ; Rats ; Male ; Mice ; Female ; Microbiota ; }, abstract = {Adult severe caries (ASC) brings severe oral dysfunction and treatment difficulties to patients, and yet no clear pathogenic mechanism for it has been found. This study is focused on the composition of dental plaque microbiome profiles in order to identify disease-relevant species and to investigate into their interactions with the S. mutans. Samples of dental plaque were collected for metagenomic analysis. The acidification, aciduricity, oxidative stress tolerance, and gtf (glucosyltransferase) gene expression of S. mutans cocultured with V. parvula which was identified as ASC-related dominant bacterium. The biofilm formation and extracellular exopolysaccharide (EPS) synthesis of dual-strain were analyzed with scanning electron microscopy (SEM), crystal violet (CV) staining, live/dead bacterial staining, and confocal laser scanning microscopy (CLSM). Furthermore, rodent model experiments were performed to validate the in vivo cariogenicity of the dual-species biofilm. The most significantly abundant taxon found associated with ASC was V. parvula. In vitro experiments found that V. parvula can effectively promote S. mutans mature biofilm formation with enhanced acid resistance, hydrogen peroxide detoxicity, and biofilm virulence. Rodent model experiments revealed that V. parvula was incapable of causing disease on its own, but it significantly heightened the biofilm virulence of S. mutans when being co-infected and augmented the progression, quantity, and severity of dental caries. Our findings demonstrated that V. parvula may act as a synergistic pathobiont to modulate the metabolic activity, spatial structure, and pathogenicity of biofilms of S. mutans in the context of ASC.IMPORTANCEAdult severe caries (ASC), as a special type of acute caries, is rarely reported and its worthiness of further study is still in dispute. Yet studies on the etiology of severe caries in adults have not found a clear pathogenic mechanism for it. Knowledge of the oral microbiota is important for the treatment of dental caries. We discovered that the interaction between V. parvula and S. mutans augments the severity of dental caries in vivo, suggesting V. parvula may act as a synergistic pathobiont exacerbating biofilm virulence of S. mutans in ASC. Our findings may improve the understanding of ASC pathogenesis and are likely to provide a basis for planning appropriate therapeutic strategies.}, }
@article {pmid39344640, year = {2024}, author = {Bamford, NC and Morris, RJ and Prescott, A and Murphy, P and Erskine, E and MacPhee, CE and Stanley-Wall, NR}, title = {TasA Fibre Interactions Are Necessary for Bacillus subtilis Biofilm Structure.}, journal = {Molecular microbiology}, volume = {122}, number = {4}, pages = {598-609}, doi = {10.1111/mmi.15315}, pmid = {39344640}, issn = {1365-2958}, support = {ALTF 471-2020//European Molecular Biology Organization/ ; BB/P001335/1/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom ; BB/R012415/1/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom ; BB/X002950/1/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom ; 200208/Z/15/Z/WT_/Wellcome Trust/United Kingdom ; }, mesh = {*Biofilms/growth &amp; development ; *Bacillus subtilis/metabolism/genetics/physiology ; *Bacterial Proteins/metabolism/genetics ; Amyloid/metabolism ; Extracellular Matrix/metabolism ; }, abstract = {The extracellular matrix of biofilms provides crucial structural support to the community and protection from environmental perturbations. TasA, a key Bacillus subtilis biofilm matrix protein, forms both amyloid and non-amyloid fibrils. Non-amyloid TasA fibrils are formed via a strand-exchange mechanism, whereas the amyloid-like form involves non-specific self-assembly. We performed mutagenesis of the N-terminus to assess the role of non-amyloid fibrils in biofilm development. We find that the N-terminal tail is essential for the formation of structured biofilms, providing evidence that the strand-exchange fibrils are the active form in the biofilm matrix. Furthermore, we demonstrate that fibre formation alone is not sufficient to give structure to the biofilm. We build an interactome of TasA with other extracellular protein components, and identify important interaction sites. Our results provide insight into how protein-matrix interactions modulate biofilm development.}, }
@article {pmid39343957, year = {2024}, author = {Samaniego, LVB and Scandelau, SL and Silva, CR and Pratavieira, S and de Oliveira Arnoldi Pellegrini, V and Dabul, ANG and Esmerino, LA and de Oliveira Neto, M and Hernandes, RT and Segato, F and Pileggi, M and Polikarpov, I}, title = {Thermothelomyces thermophilus exo- and endo-glucanases as tools for pathogenic E. coli biofilm degradation.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {22576}, pmid = {39343957}, issn = {2045-2322}, support = {2021/08780-1//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado de S&#xe3;o Paulo/ ; 306852/2021-7 and 440180/2022-8//Conselho Nacional de Desenvolvimento Cient&#xed;fico e Tecnol&#xf3;gico/ ; }, mesh = {*Biofilms/growth &amp; development/drug effects ; *Escherichia coli ; Hydrolysis ; Cellulase/metabolism/chemistry ; Hypocreales/enzymology ; }, abstract = {The escalating prevalence of drug-resistant pathogens not only jeopardizes the effectiveness of existing treatments but also increases the complexity and severity of infectious diseases. Escherichia coli is one the most common pathogens across all healthcare-associated infections. Enzymatic treatment of bacterial biofilms, targeting extracellular polymeric substances (EPS), can be used for EPS degradation and consequent increase in susceptibility of pathogenic bacteria to antibiotics. Here, we characterized three recombinant cellulases from Thermothelomyces thermophilus: a cellobiohydrolase I (TthCel7A), an endoglucanase (TthCel7B), and a cellobiohydrolase II (TthCel6A) as tools for hydrolysis of E. coli and Gluconacetobacter hansenii biofilms. Using a design mixture approach, we optimized the composition of cellulases, enhancing their synergistic activity to degrade the biofilms and significantly reducing the enzymatic dosage. In line with the crystalline and ordered structure of bacterial cellulose, the mixture of exo-glucanases (0.5 TthCel7A:0.5 TthCel6A) is effective in the hydrolysis of G. hansenii biofilm. Meanwhile, a mixture of exo- and endo-glucanases is required for the eradication of E. coli 042 and clinical E. coli biofilms with significantly different proportions of the enzymes (0.56 TthCel7B:0.44 TthCel6A and 0.6 TthCel7A:0.4 TthCel7B, respectively). X-ray diffraction pattern and crystallinity index of E. coli cellulose are comparable to those of carboxymethyl cellulose (CMC) substrate. Our results illustrate the complexity of E. coli biofilms and show that successful hydrolysis is achieved by a specific combination of cellulases, with consistent recurrence of TthCel7B endoglucanase.}, }
@article {pmid39342710, year = {2024}, author = {Li, R and Lu, MY and Guo, RB and Duan, H and Ni, BJ and Fu, SF}, title = {Life cycle assessment of hydrogenotrophic denitrification in membrane aerated biofilm reactors for sustainable wastewater treatment.}, journal = {Water research}, volume = {267}, number = {}, pages = {122529}, doi = {10.1016/j.watres.2024.122529}, pmid = {39342710}, issn = {1879-2448}, mesh = {*Biofilms ; *Denitrification ; *Bioreactors ; *Waste Disposal, Fluid/methods ; *Wastewater/chemistry ; *Hydrogen/metabolism ; Membranes, Artificial ; Water Purification/methods ; Nitrogen/metabolism ; }, abstract = {The conventional anaerobic-anoxic-oxic (AAO) process for wastewater treatment is associated with high energy consumption and pollutant emissions due to its reliance on heterotrophic denitrification. In contrast, membrane aerated biofilm reactors (MABR) coupled with hydrogenotrophic denitrification (H2-MABR) offers a more promising alternative. This study conducts a life cycle assessment (LCA) to evaluate the environmental and economic benefits of H2-MABR compared to traditional AAO processes. Results indicate that even with a limited reactor life, the application of MABR in actual wastewater treatment plants can yield over 30 % reduction in environmental and economic impacts. Using CO2 from biogas as a carbon source significantly reduces carbon emissions during the anaerobic stage, while the efficient nitrogen removal minimizes the need for wastewater recirculation and electricity consumption. The H2-driven denitrification process also avoids emissions and secondary pollution risks associated with organic electron donors. Furthermore, coupling H2-MABR with renewable energy source and Power-to-Gas technology further enhances sustainability by ensuring a stable hydrogen supply. Given the significant potential of H2-MABR for improving wastewater treatment, further research and large-scale implementation are highly encouraged.}, }
@article {pmid39342123, year = {2024}, author = {Elawady, R and Aboulela, AG and Gaballah, A and Ghazal, AA and Amer, AN}, title = {Antimicrobial Sub-MIC induces Staphylococcus aureus biofilm formation without affecting the bacterial count.}, journal = {BMC infectious diseases}, volume = {24}, number = {1}, pages = {1065}, pmid = {39342123}, issn = {1471-2334}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Staphylococcus aureus/drug effects/physiology ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology ; Humans ; *Staphylococcal Infections/microbiology/drug therapy ; Bacterial Load ; Ciprofloxacin/pharmacology ; Gentamicins/pharmacology ; }, abstract = {BACKGROUND: Biofilm formation is an essential virulence factor that creates a highly protected growth mode for Staphylococcus aureus (S. aureus) to survive in any hostile environment. Antibiotic sub-minimal inhibitory concentration (sub-MIC) may modulate the biofilm formation ability of bacterial pathogens, thereby affecting bacterial pathogenesis and infection outcomes. Intense antimicrobial therapy to treat biofilm-associated infections can control the pathogenic infection aggravation but cannot guarantee its complete eradication.<br><br>OBJECTIVE: This study aimed to assess the sub-MICs effect of 5 different antimicrobial classes on biofilm-forming capacity among Staphylococcus aureus clinical isolates using three different biofilm quantitation techniques.<br><br>METHODS: In this study, the effects of 5 different antimicrobial agents, namely, azithromycin, gentamicin, ciprofloxacin, doxycycline, and imipenem, at sub-MICs of 12.5%, 25%, and 50% were tested on 5 different clinical isolates of S. aureus. The biofilms formed in the absence and presence of different antimicrobial sub-MICs were then assessed using the following three different techniques: the crystal violet (CV) staining method, the quantitative PCR (qPCR) method, and the spread plate method (SPM).<br><br>RESULTS: Biofilm formation was significantly induced in 64% of the tested conditions using the CV technique. On the other hand, the qPCR quantifying the total bacterial count and the SPM quantifying the viable bacterial count showed significant induction only in 24% and 17.3%, respectively (Fig.&#xa0;1). The difference between CV and the other techniques indicates an increase in biofilm biomass without an increase in bacterial growth. As expected, sub-MICs did not reduce the viable cell count, as shown by the SPM. The CV staining method revealed that sub-MICs of imipenem and ciprofloxacin had the highest significance rate (80%) showing an inductive effect on the biofilm development. On the other hand, doxycycline, azithromycin, and gentamicin displayed lower significance rates of 73%, 53%, and 47%, respectively.<br><br>CONCLUSION: Exposure to sub-MIC doses of antimicrobial agents induces the biofilm-forming capacity of S. aureus via increasing the total biomass without significantly affecting the bacterial growth of viable count.}, }
@article {pmid39342036, year = {2024}, author = {Shiralizadeh, S and Farmany, A and Shokoohizadeh, L and Pourhajibagher, M and Alikhani, MY and Bahador, A}, title = {Enhancing antimicrobial efficacy against Pseudomonas aeruginosa biofilm through carbon dot-mediated photodynamic inactivation.}, journal = {AMB Express}, volume = {14}, number = {1}, pages = {108}, pmid = {39342036}, issn = {2191-0855}, support = {14000124468 and 14000117209//Vice Chancellor of Research and Technology of Hamadan University of Medical Sciences, Hamadan, IRAN/ ; }, abstract = {Pseudomonas aeruginosa biofilms shield the bacteria from antibiotics and the body's defenses, often leading to chronic infections that are challenging to treat. This study aimed to assess the impact of sub-lethal doses of antimicrobial photodynamic inactivation (sAPDI) utilizing carbon dots (CDs) derived from gentamicin and imipenem on biofilm formation and the expression of genes (pelA and pslA) associated with P. aeruginosa biofilm formation.The anti-biofilm effects of sAPDI were evaluated by exposing P. aeruginosa to sub-minimum biofilm inhibitory concentrations (sub-MBIC) of CDsGEN-NH2, CDsIMP-NH2, CDsGEN-IMP, and CDsIMP-GEN, combined with sub-lethal UVA light irradiation. Biofilm formation ability was assessed by crystal violet (CV) assay and enumeration method. Additionally, the impact of sAPDI on the expression of pelF and pslA genes was evaluated using real-time quantitative polymerase chain reaction (RT-qPCR).Compared to the control group, the sAPDI treatment with CDsGEN-NH2, CDsIMP-NH2, CDsGEN-IMP, and CDsIMP-GEN resulted in a significant reduction in biofilm activity of P. aeruginosa ATCC 27853 (P < 0.0001). The CV assay method demonstrated reductions in optical density of 83.70%, 81.08%, 89.33%, and 75.71%, while the CFU counting method showed reductions of 4.03, 3.76, 4.39, and 3.21 Log10 CFU/mL. qRT-PCR analysis revealed decreased expression of the pelA and pslA genes in P. aeruginosa ATCC 27853 following sAPDI treatment compared to the control group (P < 0.05).The results indicate that sAPDI using CDs derived from gentamicin and imipenem can decrease the biofilm formation of P. aeruginosa and the expression of the pelA and pslA genes associated with its biofilm formation.}, }
@article {pmid39341797, year = {2024}, author = {Bin Mohammad Muzaki, MZ and Subramoni, S and Summers, S and Kjelleberg, S and Rice, SA}, title = {Klebsiella pneumoniae AI-2 transporters mediate interspecies interactions and composition in a three-species biofilm community.}, journal = {NPJ biofilms and microbiomes}, volume = {10}, number = {1}, pages = {91}, pmid = {39341797}, issn = {2055-5008}, mesh = {*Biofilms/growth &amp; development ; *Klebsiella pneumoniae/genetics/metabolism ; *Pseudomonas aeruginosa/genetics/metabolism ; *Bacterial Proteins/genetics/metabolism ; Microbial Interactions ; Homoserine/analogs &amp; derivatives/metabolism ; Pseudomonas/genetics/metabolism ; Membrane Transport Proteins/metabolism/genetics ; Gene Deletion ; Biomass ; Lactones ; }, abstract = {Biofilms in nature often exist as communities. In this study, an experimental mixed-species community consisting of Pseudomonas aeruginosa, Pseudomonas protegens and Klebsiella pneumoniae was used to investigate how AI-2 transporters affect interspecies interactions and composition. The K. pneumoniae lsrB/lsrD deletion mutants had a 10-25-fold higher concentration of extracellular AI-2 compared to the wild-type. Although these deletion mutants produced monospecies biofilms of similar biomass, the substitution of these mutants for the parental strain significantly altered composition. Dual-species biofilm assays demonstrated that the changes in composition were due to the cumulative effect of pairwise interactions. It was further revealed that K. pneumoniae being present physically in the consortium was important in AI-2 mediating composition in the consortium, and that AI-2 transporters were crucial in achieving maximum biomass in the community. In conclusion, these findings demonstrate that AI-2 transporters mediate interspecies interactions and is important in maintaining the compositional equilibrium of the community.}, }
@article {pmid39341189, year = {2024}, author = {Zhao, Z and Wang, Y and Wei, Y and Peng, G and Wei, T and He, J and Li, R and Wang, Y}, title = {Distinctive patterns of bacterial community succession in the riverine micro-plastisphere in view of biofilm development and ecological niches.}, journal = {Journal of hazardous materials}, volume = {480}, number = {}, pages = {135974}, doi = {10.1016/j.jhazmat.2024.135974}, pmid = {39341189}, issn = {1873-3336}, mesh = {*Biofilms/growth &amp; development ; *Bacteria/metabolism/classification/growth &amp; development ; Microplastics ; Rivers/microbiology ; Ecosystem ; Biodegradation, Environmental ; Microbiota ; }, abstract = {Exploring plastic bacterial community succession is a crucial step in analyzing and predicting the ecological assembly processes of the plastisphere and its associated environmental impacts. However, microbial biofilm development and niche differentiation during plastic bacterial community succession have rarely scarcely considered. Here, we assessed the differences between three microplastics (MPs) and two natural polymers in terms of biofilm development and niche properties during bacterial community succession, and identified a genus of MPs-degrading bacteria with strong competitive potential in the plastisphere. MPs biofilm development exhibits secondary succession characteristics, whereas natural polymer biofilms persist during the primary succession stage. During succession in plastic bacterial communities, the relationship between nutrient resources and microbial competition was reflected in a positive correlation between species competition and niche breadth, which contradicted the common belief that increased nutrient availability leads to reduced competition. Furthermore, the co-occurrence network revealed that specialists were species with greater competitive potential within the plastisphere. Additionally, the MPs-degrading Exiguobacterium genus represented a key taxon in the plastisphere. Our study provides a reliable pathway for revealing the specificity of plastic bacterial community succession from multiple perspectives and enhances the understanding of ecological assembly processes in the plastisphere.}, }
@article {pmid39339644, year = {2024}, author = {Mahmoud, GA and Rashed, NM and El-Ganainy, SM and Salem, SH}, title = {Unveiling the Neem (Azadirachta indica) Effects on Biofilm Formation of Food-Borne Bacteria and the Potential Mechanism Using a Molecular Docking Approach.}, journal = {Plants (Basel, Switzerland)}, volume = {13}, number = {18}, pages = {}, pmid = {39339644}, issn = {2223-7747}, abstract = {Biofilms currently represent the most prevalent bacterial lifestyle, enabling them to resist environmental stress and antibacterial drugs. Natural antibacterial agents could be a safe solution for controlling bacterial biofilms in food industries without affecting human health and environmental safety. A methanolic extract of Azadirachta indica (neem) leaves was prepared and analyzed using gas chromatography-mass spectrometry for the identification of its phytochemical constituents. Four food-borne bacterial pathogens (Bacillus cereus, Novosphingobium aromaticivorans, Klebsiella pneumoniae, and Serratia marcescens) were tested for biofilm formation qualitatively and quantitatively. The antibacterial and antibiofilm properties of the extract were estimated using liquid cultures and a microtiter plate assay. The biofilm inhibition mechanisms were investigated using a light microscope and molecular docking technique. The methanolic extract contained 45 identified compounds, including fatty acids, ester, phenols, flavonoids, terpenes, steroids, and antioxidants with antimicrobial, anticancer, and anti-inflammatory properties. Substantial antibacterial activity in relation to the extract was recorded, especially at 100 μg/mL against K. pneumoniae and S. marcescens. The extract inhibited biofilm formation at 100 μg/mL by 83.83% (S. marcescens), 73.12% (K. pneumoniae), and 54.4% (N. aromaticivorans). The results indicate efficient biofilm formation by the Gram-negative bacteria S. marcescens, K. pneumoniae, and N. aromaticivorans, giving 0.74, 0.292, and 0.219 OD at 595 nm, respectively, while B. cereus was found to have a low biofilm formation potential, i.e., 0.14 OD at 595 nm. The light microscope technique shows the antibiofilm activities with the biofilm almost disappearing at 75 μg/mL and 100 μg/mL concentrations. This antibiofilm property was attributed to DNA gyrase inhibition as illustrated by the molecular docking approach.}, }
@article {pmid39339292, year = {2024}, author = {Shi, L and Zhou, X and Qi, P}, title = {Resin Acid Copper Salt, an Interesting Chemical Pesticide, Controls Rice Bacterial Leaf Blight by Regulating Bacterial Biofilm, Motility, and Extracellular Enzymes.}, journal = {Molecules (Basel, Switzerland)}, volume = {29}, number = {18}, pages = {}, pmid = {39339292}, issn = {1420-3049}, support = {32160661//The National Natural Science Foundation of China/ ; 32202359//The National Natural Science Foundation of China/ ; Guikangda K2024-9//The Scientific Research Foundation of Guiyang Healthcare Vocational University/ ; }, mesh = {*Biofilms/drug effects ; *Xanthomonas/drug effects/pathogenicity ; *Plant Diseases/microbiology/prevention &amp; control ; *Copper/chemistry/pharmacology ; *Oryza/microbiology ; Anti-Bacterial Agents/pharmacology/chemistry ; Plant Leaves ; Resins, Plant/pharmacology/chemistry ; }, abstract = {Bacterial virulence plays an important role in infection. Antibacterial virulence factors are effective for preventing crop bacterial diseases. Resin acid copper salt as an effective inhibitor exhibited excellent anti-Xanthomonas oryzae pv. oryzae (Xoo) activity with an EC50 of 50.0 μg mL[-1]. Resin acid copper salt (RACS) can reduce extracellular polysaccharides' (EPS's) biosynthesis by down-regulating gumB relative expression. RACS can also effectively inhibit the bio-mass of Xoo biofilm. It can reduce the activity of Xoo extracellular amylase at a concentration of 100 μg mL[-1]. Meanwhile, the results of virtual computing suggested that RACS is an enzyme inhibitor. RACS displayed good curative activity with a control effect of 38.5%. Furthermore, the result of the phytotoxicity assessment revealed that RACS exhibited slight toxicity compared with the control at a concentration of 200 μg mL[-1]. The curative effect was increased to 45.0% using an additional antimicrobial agent like orange peel essential oil. RACS markedly inhibited bacterial pathogenicity at a concentration of 100 μg mL[-1] in vivo.}, }
@article {pmid39338585, year = {2024}, author = {Hantus, CE and Moppel, IJ and Frizzell, JK and Francis, AE and Nagashima, K and Ryno, LM}, title = {L-Rhamnose Globally Changes the Transcriptome of Planktonic and Biofilm Escherichia coli Cells and Modulates Biofilm Growth.}, journal = {Microorganisms}, volume = {12}, number = {9}, pages = {}, pmid = {39338585}, issn = {2076-2607}, support = {MCB-2226953//National Science Foundation/ ; DBI-1828041//National Science Foundation/ ; Cottrell Scholar Award//Research Corporation for Science Advancement/ ; }, abstract = {L-rhamnose, a naturally abundant sugar, plays diverse biological roles in bacteria, influencing biofilm formation and pathogenesis. This study investigates the global impact of L-rhamnose on the transcriptome and biofilm formation of PHL628 E. coli under various experimental conditions. We compared growth in planktonic and biofilm states in rich (LB) and minimal (M9) media at 28 °C and 37 °C, with varying concentrations of L-rhamnose or D-glucose as a control. Our results reveal that L-rhamnose significantly affects growth kinetics and biofilm formation, particularly reducing biofilm growth in rich media at 37 °C. Transcriptomic analysis through RNA-seq showed that L-rhamnose modulates gene expression differently depending on the temperature and media conditions, promoting a planktonic state by upregulating genes involved in rhamnose transport and metabolism and downregulating genes related to adhesion and biofilm formation. These findings highlight the nuanced role of L-rhamnose in bacterial adaptation and survival, providing insight into potential applications in controlling biofilm-associated infections and industrial biofilm management.}, }
@article {pmid39338564, year = {2024}, author = {Ikeda, H and Maeda, S}, title = {Characterization of Escherichia coli Persisters from Biofilm Culture: Multiple Dormancy Levels and Multigenerational Memory in Formation.}, journal = {Microorganisms}, volume = {12}, number = {9}, pages = {}, pmid = {39338564}, issn = {2076-2607}, support = {19K05791//Japan Society for the Promotion of Science/ ; }, abstract = {Persister cells (PCs), a subpopulation occurring within normal cells, exhibit a transient tolerance to antibiotics because of their dormant state. PCs are categorized into two types: type I PCs, which emerge during the stationary phase, and type II PCs, which emerge during the logarithmic phase. Using the conventional colony-forming method, we previously demonstrated that type I PCs of Escherichia coli form more frequently in air-solid biofilm culture than in liquid culture. In the current study, we modified a cell filamentation method as a more efficient and rapid alternative for quantifying PCs. This modified method yielded results consistent with those of the conventional method with 10[3]-10[4] times higher sensitivity and less detection time, within several hours, and further revealed the existence of multiple levels of type I PCs, including a substantial number of deeply dormant cells. This study also discovered a potential epigenetic memory mechanism, spanning several generations (four or six cell divisions), which influences type II PC formation based on prior biofilm experience in E. coli.}, }
@article {pmid39338555, year = {2024}, author = {Martinet, MG and Lohde, M and Higazy, D and Brandt, C and Pletz, MW and Middelboe, M and Makarewicz, O and Ciofu, O}, title = {Diversification of Pseudomonas aeruginosa Biofilm Populations under Repeated Phage Exposures Decreases the Efficacy of the Treatment.}, journal = {Microorganisms}, volume = {12}, number = {9}, pages = {}, pmid = {39338555}, issn = {2076-2607}, support = {861323//Marie Sk&#x142;odowska-Curie grant/ ; 13N15720//Federal Ministry of Education and Research/ ; 19-10-0406//Aase og Ejnar Danielsens Fond/ ; }, abstract = {Phage therapy has been proposed as a therapeutic alternative to antibiotics for the treatment of chronic, biofilm-related P. aeruginosa infections. To gain a deeper insight into the complex biofilm-phage interactions, we investigated in the present study the effect of three successive exposures to lytic phages of biofilms formed by the reference strains PAO1 and PA14 as well as of two sequential clinical P. aeruginosa isolates from the sputum of a patient with cystic fibrosis (CF). The Calgary device was employed as a biofilm model and the efficacy of phage treatment was evaluated by measurements of the biomass stained with crystal violet (CV) and of the cell density of the biofilm bacterial population (CFU/mL) after each of the three phage exposures. The genetic alterations of P. aeruginosa isolates from biofilms exposed to phages were investigated by whole-genome sequencing. We show here that the anti-biofilm efficacy of the phage treatment decreased rapidly with repeated applications of lytic phages on P. aeruginosa strains with different genetic backgrounds. Although we observed the maintenance of a small subpopulation of sensitive cells after repeated phage treatments, a fast recruitment of mechanisms involved in the persistence of biofilms to the phage attack occurred, mainly by mutations causing alterations of the phage receptors. However, mutations causing phage-tolerant phenotypes such as alginate-hyperproducing mutants were also observed. In conclusion, a decreased anti-biofilm effect occurred after repeated exposure to lytic phages of P. aeruginosa biofilms due to the recruitment of different resistance and tolerance mechanisms.}, }
@article {pmid39338515, year = {2024}, author = {Tentori, EF and Wang, N and Devin, CJ and Richardson, RE}, title = {Treatment of Anaerobic Digester Liquids via Membrane Biofilm Reactors: Simultaneous Aerobic Methanotrophy and Nitrogen Removal.}, journal = {Microorganisms}, volume = {12}, number = {9}, pages = {}, pmid = {39338515}, issn = {2076-2607}, support = {N/A//Cornell Sloan Fellowship/ ; N/A//Cornell Atkinson Center Academic Venture Fund/ ; N/A//EPA People, Prosperity, and the Planet (EPA-P3) Program/ ; }, abstract = {Anaerobic digestion (AD) produces useful biogas and waste streams with high levels of dissolved methane (CH4) and ammonium (NH4[+]), among other nutrients. Membrane biofilm reactors (MBfRs), which support dissolved methane oxidation in the same reactor as simultaneous nitrification and denitrification (ME-SND), are a potential bubble-less treatment method. Here, we demonstrate ME-SND taking place in single-stage, AD digestate liquid-fed MBfRs, where oxygen (O2) and supplemental CH4 were delivered via pressurized membranes. The effects of two O2 pressures, leading to different O2 fluxes, on CH4 and N removal were examined. MBfRs achieved up to 98% and 67% CH4 and N removal efficiencies, respectively. The maximum N removal rates ranged from 57 to 94 mg N L[-1] d[-1], with higher overall rates observed in reactors with lower O2 pressures. The higher-O2-flux condition showed NO2[-] as a partial nitrification endpoint, with a lower total N removal rate due to low N2 gas production compared to lower-O2-pressure reactors, which favored complete nitrification and denitrification. Membrane biofilm 16S rRNA amplicon sequencing showed an abundance of aerobic methanotrophs (especially Methylobacter, Methylomonas, and Methylotenera) and enrichment of nitrifiers (especially Nitrosomonas and Nitrospira) and anammox bacteria (especially Ca. Annamoxoglobus and Ca. Brocadia) in high-O2 and low-O2 reactors, respectively. Supplementation of the influent with nitrite supported evidence that anammox bacteria in the low-O2 condition were nitrite-limited. This work highlights coupling of aerobic methanotrophy and nitrogen removal in AD digestate-fed reactors, demonstrating the potential application of ME-SND in MBfRs for the treatment of AD's residual liquids and wastewater. Sensor-based tuning of membrane O2 pressure holds promise for the optimization of bubble-less treatment of excess CH4 and NH4[+] in wastewater.}, }
@article {pmid39338470, year = {2024}, author = {Martinho, I and Braz, M and Duarte, J and Brás, A and Oliveira, V and Gomes, NCM and Pereira, C and Almeida, A}, title = {The Potential of Phage Treatment to Inactivate Planktonic and Biofilm-Forming Pseudomonas aeruginosa.}, journal = {Microorganisms}, volume = {12}, number = {9}, pages = {}, pmid = {39338470}, issn = {2076-2607}, abstract = {Pseudomonas aeruginosa is a common cause of hospital-acquired infections and exhibits a strong resistance to antibiotics. An alternative treatment option for bacterial infections is the use of bacteriophages (or phages). In this study, two distinct phages, VB_PaD_phPA-G (phPA-G) and VB_PaN_phPA-Intesti (phPA-Intesti), were used as single suspensions or in a phage cocktail to inactivate the planktonic cells and biofilms of P. aeruginosa. Preliminary experiments in culture medium showed that phage phPA-Intesti (reductions of 4.5-4.9 log CFU/mL) outperformed phPA-G (reductions of 0.6-2.6 log CFU/mL) and the phage cocktail (reduction of 4.2 log CFU/mL). Phage phPA-Intesti caused a maximum reduction of 5.5 log CFU/cm[2] in the P. aeruginosa biofilm in urine after 4 h of incubation. The combination of phage phPA-Intesti and ciprofloxacin did not improve the efficacy of bacterial inactivation nor reduce the development of resistant mutants. However, the development of resistant bacteria was lower in the combined treatment with the phage and the antibiotic compared to treatment with the antibiotic alone. This phage lacks known toxins, virulence, antibiotic resistance, and integrase genes. Overall, the results suggest that the use of phage phPA-Intesti could be a potential approach to control urinary tract infections (UTIs), namely those caused by biofilm-producing and multidrug-resistant strains of P. aeruginosa.}, }
@article {pmid39338441, year = {2024}, author = {Thippani, S and Patel, NJ and Jathan, J and Filush, K and Socarras, KM and DiLorenzo, J and Balasubramanian, K and Gupta, K and Ortiz Aleman, G and Pandya, JM and Kavitapu, VV and Zeng, D and Miller, JC and Sapi, E}, title = {Evidence for the Presence of Borrelia burgdorferi Biofilm in Infected Mouse Heart Tissues.}, journal = {Microorganisms}, volume = {12}, number = {9}, pages = {}, pmid = {39338441}, issn = {2076-2607}, abstract = {Borrelia burgdorferi, the bacterium responsible for Lyme disease, has been shown to form antimicrobial-tolerant biofilms, which protect it from unfavorable conditions. Bacterial biofilms are known to significantly contribute to severe inflammation, such as carditis, a common manifestation of Lyme disease. However, the role of B. burgdorferi biofilms in the development of Lyme carditis has not been thoroughly investigated due to the absence of an appropriate model system. In this study, we examined heart tissues from mice infected with B. burgdorferi for the presence of biofilms and inflammatory markers using immunohistochemistry (IHC), combined fluorescence in situ hybridization FISH/IHC, 3D microscopy, and atomic force microscopy techniques. Our results reveal that B. burgdorferi spirochetes form aggregates with a known biofilm marker (alginate) in mouse heart tissues. Furthermore, these biofilms induce inflammation, as indicated by elevated levels of murine C-reactive protein near the biofilms. This research provides evidence that B. burgdorferi can form biofilms in mouse heart tissue and trigger inflammatory processes, suggesting that the mouse model is a valuable tool for future studies on B. burgdorferi biofilms.}, }
@article {pmid39338422, year = {2024}, author = {Thakur, P and Gopalakrishnan, V and Saxena, P and Subramaniam, M and Goh, KM and Peyton, B and Fields, M and Sani, RK}, title = {Influence of Copper on Oleidesulfovibrio alaskensis G20 Biofilm Formation.}, journal = {Microorganisms}, volume = {12}, number = {9}, pages = {}, pmid = {39338422}, issn = {2076-2607}, support = {1736255//National Science Foundation/ ; 1849206//National Science Foundation/ ; 1920954//National Science Foundation/ ; }, abstract = {Copper is known to have toxic effects on bacterial growth. This study aimed to determine the influence of copper ions on Oleidesulfovibrio alaskensis G20 biofilm formation in a lactate-C medium supplemented with variable copper ion concentrations. OA G20, when grown in media supplemented with high copper ion concentrations of 5, 15, and 30 µM, exhibited inhibited growth in its planktonic state. Conversely, under similar copper concentrations, OA G20 demonstrated enhanced biofilm formation on glass coupons. Microscopic studies revealed that biofilms exposed to copper stress demonstrated a change in cellular morphology and more accumulation of carbohydrates and proteins than controls. Consistent with these findings, sulfur (dsrA, dsrB, sat, aprA) and electron transport (NiFeSe, NiFe, ldh, cyt3) genes, polysaccharide synthesis (poI), and genes involved in stress response (sodB) were significantly upregulated in copper-induced biofilms, while genes (ftsZ, ftsA, ftsQ) related to cellular division were negatively regulated compared to controls. These results indicate that the presence of copper ions triggers alterations in cellular morphology and gene expression levels in OA G20, impacting cell attachment and EPS production. This adaptation, characterized by increased biofilm formation, represents a crucial strategy employed by OA G20 to resist metal ion stress.}, }
@article {pmid39337326, year = {2024}, author = {Krzyżek, P and Migdał, P and Krzyżanowska, B and Duda-Madej, A}, title = {Optimization of Helicobacter pylori Biofilm Formation in In Vitro Conditions Mimicking Stomach.}, journal = {International journal of molecular sciences}, volume = {25}, number = {18}, pages = {}, pmid = {39337326}, issn = {1422-0067}, support = {SUBK.A130.23.057//Wroclaw Medical University/ ; IA/SP/453975/2020//National Centre for Research and Development/ ; }, mesh = {*Biofilms/growth &amp; development/drug effects ; *Helicobacter pylori/physiology ; Humans ; *Coculture Techniques/methods ; Stomach/microbiology ; Helicobacter Infections/microbiology ; Cell Line ; }, abstract = {Helicobacter pylori is one of the most common bacterial pathogens worldwide and the main etiological agent of numerous gastric diseases. The frequency of multidrug resistance of H. pylori is growing and the leading factor related to this phenomenon is its ability to form biofilm. Therefore, the establishment of a proper model to study this structure is of critical need. In response to this, the aim of this original article is to validate conditions of the optimal biofilm development of H. pylori in monoculture and co-culture with a gastric cell line in media simulating human fluids. Using a set of culture-based and microscopic techniques, we proved that simulated transcellular fluid and simulated gastric fluid, when applied in appropriate concentrations, stimulate autoaggregation and biofilm formation of H. pylori. Additionally, using a co-culture system on semi-permeable membranes in media imitating the stomach environment, we were able to obtain a monolayer of a gastric cell line with H. pylori biofilm on its surface. We believe that the current model for H. pylori biofilm formation in monoculture and co-culture with gastric cells in media containing host-mimicking fluids will constitute a platform for the intensification of research on H. pylori biofilms in in vitro conditions that simulate the human body.}, }
@article {pmid39335547, year = {2024}, author = {Pleskova, SN and Bezrukov, NA and Nikolaeva, ED and Boryakov, AV and Kuzina, OV}, title = {Rapid Detection of Acinetobacter baumannii Suspension and Biofilm Nanomotion and Antibiotic Resistance Estimation.}, journal = {Biomedicines}, volume = {12}, number = {9}, pages = {}, pmid = {39335547}, issn = {2227-9059}, support = {22-14-20001//Russian Science Foundation/ ; }, abstract = {OBJECTIVES: To develop a system for the rapid detection of Acinetobacter baumannii 173-p1 antibiotic resistance (to ensure reliable fixation of bacteria on a cantilever without losing their nanomotion, to show that nanomotion is due to bacterial metabolism, to compare the nanomotion of bacteria in suspension form and inside of the biofilms), to study the sensitivity/resistance of A. baumannii 173-p1 to antibiotics (lincomycin, ceftriaxone and doxycycline) using the oscillation method of atomic force microscopy and to evaluate the sensitivity and speed of the method in comparison with the classical disk diffusion method.<br><br>METHODS: The oscillation mode of atomic force microscopy, scanning electron microscopy and the classical disk diffusion method were used for a complex parallel study of A. baumannii 173-p1 antibiotic resistance, which included testing of fixing agents (poly-L-lysine, rosin and fibronectin), comparison of bacterial metabolism in a set of media (normal saline solution, meat-peptone broth and lysogeny broth) and assessment of antibiotic sensitivity/resistance per se.<br><br>RESULTS: A method for express testing of Acinetobacter baumannii antibiotic resistance using AFM was developed; it is shown that bacterial nanomotion directly correlates with bacteria metabolic activity and that bacterial nanomotion is more easily detected in suspension form, rather than in biofilms.<br><br>CONCLUSION: The express testing method gave results that are completely comparable with the classical disk diffusion test and with the results of morphology studies by the SEM method, but it significantly exceeded them in speed, allowing a conclusion to be made on the sensitivity/resistance of bacteria less than an hour after the start of the diagnostics.}, }
@article {pmid39335057, year = {2024}, author = {Wang, C and Zhao, J and Lin, Y and Lwin, SZC and El-Telbany, M and Masuda, Y and Honjoh, KI and Miyamoto, T}, title = {Characterization of Two Novel Endolysins from Bacteriophage PEF1 and Evaluation of Their Combined Effects on the Control of Enterococcus faecalis Planktonic and Biofilm Cells.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {9}, pages = {}, pmid = {39335057}, issn = {2079-6382}, abstract = {Endolysin, a bacteriophage-derived lytic enzyme, has emerged as a promising alternative antimicrobial agent against rising multidrug-resistant bacterial infections. Two novel endolysins LysPEF1-1 and LysPEF1-2 derived from Enterococcus phage PEF1 were cloned and overexpressed in Escherichia coli to test their antimicrobial efficacy against multidrug-resistant E. faecalis strains and their biofilms. LysPEF1-1 comprises an enzymatically active domain and a cell-wall-binding domain originating from the NLPC-P60 and SH3 superfamilies, while LysPEF1-2 contains a putative peptidoglycan recognition domain that belongs to the PGRP superfamily. LysPEF1-1 was active against 89.86% (62/69) of Enterococcus spp. tested, displaying a wider antibacterial spectrum than phage PEF1. Moreover, two endolysins demonstrated lytic activity against additional gram-positive and gram-negative species pretreated with chloroform. LysPEF1-1 showed higher activity against multidrug-resistant E. faecalis strain E5 than LysPEF1-2. The combination of two endolysins effectively reduced planktonic cells of E5 in broth and was more efficient at inhibiting biofilm formation and removing biofilm cells of E. faecalis JCM 7783[T] than used individually. Especially at 4 °C, they reduced viable biofilm cells by 4.5 log after 2 h of treatment on glass slide surfaces. The results suggest that two novel endolysins could be alternative antimicrobial agents for controlling E. faecalis infections.}, }
@article {pmid39335053, year = {2024}, author = {Aleksic Sabo, V and Škorić, D and Jovanović-Šanta, S and Knezevic, P}, title = {Exploring Biofilm-Related Traits and Bile Salt Efficacy as Anti-Biofilm Agents in MDR Acinetobacter baumannii.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {9}, pages = {}, pmid = {39335053}, issn = {2079-6382}, support = {451-03-66/2024-03/ 200125 &amp; 451-03-65/2024-03/200125//Ministry of Science, Technological Development and Innovation of the Republic of Serbia/ ; }, abstract = {Acinetobacter baumannii has been designated as a critical priority pathogen by the World Health Organization for the development of novel antimicrobial agents. This study aimed to investigate both the phenotypic and genotypic traits of multidrug-resistant (MDR) A. baumannii strains, along with the effects of natural bile salts on biofilm formation. The research analyzed phenotypic traits, including autoaggregation, hydrophobicity, twitching motility, lectin production, and biofilm formation, as well as genotypic traits such as the presence of bap and blaPER-1 genes in twenty wound and eight environmental MDR A. baumannii isolates. While all strains were identified as good biofilm producers, no statistically significant correlation was detected between the examined traits and biofilm formation. However, differences in biofilm production were observed between environmental and wound isolates. The natural bile salts Na-cholate, Na-deoxycholate, and Na-chenodeoxycholate demonstrated effective anti-A. baumannii activity (MIC = 0.25-10 mg mL[-1]), with significant anti-biofilm effects. Na-deoxycholate and Na-chenodeoxycholate inhibited 94-100% of biofilm formation at super-MIC concentrations (8-32 mg mL[-1]). This study underscores the urgent need for innovative strategies to combat antibiotic resistance and biofilm formation in A. baumannii, highlighting the potential of natural bile salts as promising biofilm inhibitors and encouraging further research into their modification and combination with other antimicrobials.}, }
@article {pmid39335049, year = {2024}, author = {Afonso, L and Grzegorczyk, KG and Salomão, JM and Basso, KR and Alves, LC and Silva, MCD and Chryssafidis, AL and Gionco-Cano, B and Yamada-Ogatta, SF and Andrade, G}, title = {Fluopsin C Promotes Biofilm Removal of XDR Acinetobacter baumannii and Presents an Additive Effect with Polymyxin B on Planktonic Cells.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {9}, pages = {}, pmid = {39335049}, issn = {2079-6382}, support = {439754/2018-6//National Council for Scientific and Technological Development/ ; 406016/2022-4//National Council for Scientific and Technological Development/ ; }, abstract = {Acinetobacter baumannii emerged as one of the most important pathogens for the development of new antimicrobials due to the worldwide detection of isolates resistant to all commercial antibiotics, especially in nosocomial infections. Biofilm formation enhances A. baumannii survival by impairing antimicrobial action, being an important target for new antimicrobials. Fluopsin C (FlpC) is an organocupric secondary metabolite with broad-spectrum antimicrobial activity. This study aimed to evaluate the antibiofilm activity of FlpC in established biofilms of extensively drug-resistant A. baumannii (XDRAb) and the effects of its combination with polymyxin B (PolB) on planktonic cells. XDRAb susceptibility profiles were determined by Vitek 2 Compact, disk diffusion, and broth microdilution. FlpC and PolB interaction was assessed using the microdilution checkerboard method and time-kill kinetics. Biofilms of XDRAb characterization and removal by FlpC exposure were assessed by biomass staining with crystal violet. Confocal Laser Scanning Microscopy was used to determine the temporal removal of the biofilms using DAPI, and cell viability using live/dead staining. The minimum inhibitory concentration (MIC) of FlpC on XDRAb was 3.5 µg mL[-1]. Combining FlpC + PolB culminated in an additive effect, increasing bacterial susceptibility to both antibiotics. FlpC-treated 24 h biofilms reached a major biomass removal of 92.40 ± 3.38% (isolate 230) using 7.0 µg mL[-1] FlpC. Biomass removal occurred significantly over time through the dispersion of the extracellular matrix and decreasing cell number and viability. This is the first report of FlpC's activity on XDRAb and the compound showed a promissory response on planktonic and sessile cells, making it a candidate for the development of a new antimicrobial product.}, }
@article {pmid39334993, year = {2024}, author = {Li, H and Yang, Z and Khan, SA and Walsh, LJ and Seneviratne, CJ and Ziora, ZM}, title = {Characteristics of Metallic Nanoparticles (Especially Silver Nanoparticles) as Anti-Biofilm Agents.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {9}, pages = {}, pmid = {39334993}, issn = {2079-6382}, abstract = {Biofilm-associated infections account for a large proportion of chronic diseases and pose a major health challenge. Metal nanoparticles offer a new way to address this problem, by impairing microbial growth and biofilm formation and by causing degradation of existing biofilms. This review of metal nanoparticles with antimicrobial actions included an analysis of 20 years of journal papers and patent applications, highlighting the progress over that time. A network analysis of relevant publications showed a major focus on the eradication of single-species biofilms formed under laboratory conditions, while a bibliometric analysis showed growing interest in combining different types of metal nanoparticles with one another or with antibiotics. The analysis of patent applications showed considerable growth over time, but with relatively few patents progressing to be granted. Overall, this profile shows that intense interest in metal nanoparticles as anti-biofilm agents is progressing beyond the confines of simple laboratory biofilm models and coming closer to clinical application. Looking to the future, metal nanoparticles may provide a sustainable approach to combatting biofilms of drug-resistant bacteria.}, }
@article {pmid39334983, year = {2024}, author = {Piccirillo, A and Tolosi, R and Mughini-Gras, L and Kers, JG and Laconi, A}, title = {Drinking Water and Biofilm as Sources of Antimicrobial Resistance in Free-Range Organic Broiler Farms.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {9}, pages = {}, pmid = {39334983}, issn = {2079-6382}, support = {2024BCA1SIDPROGETTI-00139//Department of Comparative Biomedicine and Food Science, University of Padua/ ; }, abstract = {Drinking water distribution systems (DWDSs) represent an ideal environment for biofilm formation, which can harbor pathogenic and antimicrobial-resistant bacteria. This study aimed to assess longitudinally the microbial community composition and antimicrobial resistance (AMR), as determined by 16S rRNA NGS and qPCR, respectively, in drinking water (DW) and biofilm from DWDSs, as well as faeces, of free-range organic broiler farms. The role of DWDSs in AMR gene (ARG) dissemination within the farm environment and transmission to animals, was also assessed. DW and biofilm microbial communities differed from those of faecal samples. Moreover, potentially pathogenic and opportunistic bacteria (e.g., Staphylococcaceae) were identified in water and biofilms. High prevalence and abundance of ARGs conferring resistance to carbapenems (i.e., blaNDM), 3rd and 4th generation cephalosporins (i.e., blaCMY-2), (fluoro)quinolones (i.e., qnrS), and polymyxins (i.e., mcr-3 and mcr-5) were detected in DW, biofilm, and faecal samples, which is of concern for both animal and human health. Although other factors (e.g., feed, pests, and wildlife) may contribute to the dissemination of AMR in free-range organic poultry farms, this study indicates that DWDSs can also play a role.}, }
@article {pmid39333031, year = {2024}, author = {Pal, S and Jain, D and Biswal, S and Rastogi, SK and Kumar, G and Ghosh, AS}, title = {The physiological role of Acinetobacter baumannii DacC is exerted through influencing cell shape, biofilm formation, the fitness of survival, and manifesting DD-carboxypeptidase and beta-lactamase dual-enzyme activities.}, journal = {FEMS microbiology letters}, volume = {371}, number = {}, pages = {}, doi = {10.1093/femsle/fnae079}, pmid = {39333031}, issn = {1574-6968}, support = {#BT/PR45312/NER/95/1941/2022//Department of Biotechnology, GOI/ ; }, mesh = {*Acinetobacter baumannii/drug effects/enzymology/genetics/physiology ; Anti-Bacterial Agents/pharmacology ; Bacterial Proteins/genetics/metabolism ; beta-Lactamases/genetics/metabolism ; beta-Lactams/pharmacology ; *Biofilms/growth &amp; development ; *Carboxypeptidases/genetics/metabolism ; Gene Deletion ; Microbial Sensitivity Tests ; }, abstract = {With the growing threat of drug-resistant Acinetobacter baumannii, there is an urgent need to comprehensively understand the physiology of this nosocomial pathogen. As penicillin-binding proteins are attractive targets for antibacterial therapy, we have tried to explore the physiological roles of two putative DD-carboxypeptidases, viz., DacC and DacD, in A. baumannii. Surprisingly, the deletion of dacC resulted in a reduced growth rate, loss of rod-shaped morphology, reduction in biofilm-forming ability, and enhanced susceptibility towards beta-lactams. In contrast, the deletion of dacD had no such effect. Interestingly, ectopic expression of dacC restored the lost phenotypes. The ∆dacCD mutant showed properties similar to the ∆dacC mutant. Conversely, in vitro enzyme kinetics assessments reveal that DacD is a stronger DD-CPase than DacC. Finally, we conclude that DacC might have DD-CPase and beta-lactamase activities, whereas DacD is a strong DD-CPase.}, }
@article {pmid39332602, year = {2025}, author = {Zhou, Y and Chang, J and Zhang, M and Li, X and Luo, X and Li, W and Tian, Z and Zhang, N and Ni, B and Zhang, Y and Lu, R}, title = {GefB, a GGDEF domain-containing protein, affects motility and biofilm formation of Vibrio parahaemolyticus and is regulated by quorum sensing regulators.}, journal = {Gene}, volume = {933}, number = {}, pages = {148968}, doi = {10.1016/j.gene.2024.148968}, pmid = {39332602}, issn = {1879-0038}, mesh = {*Vibrio parahaemolyticus/genetics/metabolism ; *Biofilms/growth &amp; development ; *Quorum Sensing/genetics ; *Bacterial Proteins/genetics/metabolism ; *Cyclic GMP/metabolism/analogs &amp; derivatives ; *Gene Expression Regulation, Bacterial ; Flagella/metabolism/genetics ; Transcription Factors ; }, abstract = {Vibrio parahaemolyticus (V. parahaemolyticus) stands as the predominant etiological agent responsible for gastroenteritis associated with the consumption of seafood. Cyclic di-guanosine monophosphate (c-di-GMP), a secondary messenger in bacteria, controls multiple bacterial behaviors including pathogenesis, the development of biofilms, and motility. The protein GefB (VPA1478), characterized by the presence of a GGDEF domain, inhibits the swarming motility of V. parahaemolyticus. In this study, we showed that deletion of gefB remarkably reduced cellular c-di-GMP level and biofilm formation by V. parahaemolyticus, but significantly enhanced the swimming and swarming motility. In addition, GefB inhibited the polar and lateral flagellar genes but activated genes associated with exopolysaccharide production of V. parahaemolyticus. The data also demonstrated that vpa1477 and gefB are co-transcribed as a single transcriptional unit, designated as vpa1477-gefB. Transcription of vpa1477-gefB was under the collective regulation of the master quorum sensing (QS) regulators AphA and OpaR, which function at low (LCD) and high cell density (HCD), respectively. AphA positively regulated vpa1477-gefB transcription at LCD, whereas OpaR negatively regulated its transcription at HCD. The findings significantly enhance our comprehension of the metabolism and regulatory mechanisms of c-di-GMP in V. parahaemolyticus.}, }
@article {pmid39330701, year = {2024}, author = {Tort, S and Öztürk, ZC and Kaynak-Onurdağ, F and Mutlu-Ağardan, NB}, title = {Preparation and evaluation the effects of retinoic acid loaded proliposomal nanofibers on microbial biofilm inhibition.}, journal = {Pharmaceutical development and technology}, volume = {29}, number = {9}, pages = {955-965}, doi = {10.1080/10837450.2024.2411034}, pmid = {39330701}, issn = {1097-9867}, mesh = {*Biofilms/drug effects ; *Nanofibers/chemistry ; *Tretinoin/pharmacology/administration &amp; dosage ; *Liposomes ; Anti-Bacterial Agents/pharmacology/administration &amp; dosage ; Drug Delivery Systems/methods ; Povidone/chemistry ; Propionibacterium acnes/drug effects ; Acne Vulgaris/drug therapy/microbiology ; }, abstract = {The electrospinning method involves the production of different drug delivery systems using various polymers. The production of proliposomes with electrospinning provides the hybridization of two novel drug delivery systems. Retinoic acid, also known as all-trans retinoic acid (ATRA), is a common and effective drug for acne therapy. This study aimed to prepare ATRA-loaded proliposomal nanofibers and evaluate their effectiveness on microbial biofilm inhibition. Blank and ATRA-loaded proliposomal nanofiber formulations were fabricated in various polyvinylpyrrolidone, phosphatidylcholine and cholesterol ratios. TEM images verified the rapid formation of the liposomes after the hydration of nanofibers. The vesicle size, polydispersity index and zeta potential values of self-assembled liposomes were measured. The vesicle size values were found to be 321.9-363.8 nm with PDI values varying between 0.332 and 0.511 and zeta potential values of (-16.8) to (-20.5)mV. ATRA-loaded proliposomal nanofibers provided higher bioadhesion (0.25 mJ/cm[2]) than the commercial cream (0.07 mJ/cm[2]). The short-term stability results showed that the initial characteristics remained for three months at 4 °C. The proposed ATRA-loaded self-assembled proliposomal system provided antibacterial, fungistatic or fungicidal effects superior to retinoic acid itself and inhibited biofilm formation in lower concentrations. This approach can combine the stability advantage of nanofibers in the dry state with the high effectiveness of liposomes in acne treatment presenting antibacterial and anti-biofilm-forming activity against Candida albicans and Cutibacterium acnes.}, }
@article {pmid39326804, year = {2024}, author = {Upadhyay, A and Pal, D and Kumar, A}, title = {Cellulase exhibited a therapeutic potential to inhibit Salmonella enterica serovar Typhi biofilm by targeting multiple regulatory proteins of biofilm.}, journal = {Microbial pathogenesis}, volume = {196}, number = {}, pages = {106979}, doi = {10.1016/j.micpath.2024.106979}, pmid = {39326804}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Salmonella typhi/drug effects ; *Cellulase/metabolism ; *Bacterial Proteins/metabolism ; *Anti-Bacterial Agents/pharmacology ; *Cellulose/metabolism ; Microbial Sensitivity Tests ; Molecular Docking Simulation ; }, abstract = {Biofilm-mediated Salmonella enterica serovar Typhi (Salmonella Ser. Typhi) infections are a growing global health issue due to the formation of antibiotic resistance. The study aimed to discover some of the druggable target proteins of Salmonella Ser. Typhi biofilm and antibiofilm enzyme to prevent Salmonella Ser. Typhi biofilm-mediated infection. Enzymatic therapy has demonstrated effective therapeutic results against bacterial infections due to its specificity and high binding capacity to the target. Therefore, this study focused on the computational interaction between the cellulase enzyme and Salmonella Ser. Typhi biofilm targets proteins with help of the various computational experiments such as ADMET (absorption, distribution, metabolism, excretion, and toxicity), protein-protein interactions, MMGBSA, etc. Further, in vitro validations of the typhoidal biofilm and cellulose presence in Salmonella Ser. Typhi biofilm was conducted using Scanning Electron Microscopy (SEM), Fourier transform infrared spectroscopy, and Raman analysis. Additionally, a minimum biofilm inhibitory concentration assay for cellulase was conducted and find out the optimized cellulase concentration which showed its inhibitory effect on the Salmonella Ser. Typhi. The cellulase antibiofilm effect was analyzed with the help of SEM analysis. Further, the cellulose content in Salmonella Ser. Typhi was quantified before and after treatment of cellulase enzyme. As a result, 58.82 % cellulose content was decreased due to cellulase treatment in Salmonella Ser. Typhi. From the seven selected typhoidal biofilm regulatory proteins of Salmonella Ser. Typhi, we identified only five potential druggable targets: BcsA, CsgE, OmpR, CsgF, and CsgD. The BcsA protein is responsible for cellulose production in Salmonella Ser. Typhi biofilm. Consequently, cellulose worked as a fascinating drug target in Salmonella Ser. Typhi biofilm. Therefore, we used cellulase as a potential antibiofilm enzyme for target-based disruption of biofilm. The cellulase showed a high binding affinity with all five identified target proteins [BcsA(-205.62 kcal/mol) > CsgE(-108.20 kcal/mol) > OmpR(-107.58 kcal/mol) > CsgF(-73.74 kcal/mol) > CsgD(-66.61 kcal/mol)] in the protein-protein interaction analysis. Our computational analysis suggests that the cellulase enzyme may be used as a potential antibiofilm enzyme against Salmonella Ser. Typhi biofilm.}, }
@article {pmid39326803, year = {2024}, author = {Francis, AL and Namasivayam, SKR and Samrat, K}, title = {Potential of silver nanoparticles synthesized from Justicia adhatoda metabolites for inhibiting biofilm on urinary catheters.}, journal = {Microbial pathogenesis}, volume = {196}, number = {}, pages = {106957}, doi = {10.1016/j.micpath.2024.106957}, pmid = {39326803}, issn = {1096-1208}, mesh = {*Biofilms/drug effects ; *Silver/pharmacology/chemistry ; *Urinary Catheters/microbiology ; *Metal Nanoparticles/chemistry ; *Justicia/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; *Microbial Sensitivity Tests ; Animals ; Spectroscopy, Fourier Transform Infrared ; X-Ray Diffraction ; Humans ; Zebrafish ; Microscopy, Electron, Scanning ; Plant Extracts/pharmacology/chemistry ; Bacteria/drug effects ; Pseudomonas aeruginosa/drug effects ; Particle Size ; Escherichia coli/drug effects ; }, abstract = {In the present study, we investigated the anti-biofilm effect of urinary catheters fabricated with biogenic nanoparticles synthesized from metabolites of Justicia adhatoda under in vitro conditions against human pathogenic bacteria. Silver nanoparticles were synthesized in the reaction mixture composed of 2 % w/v of 0.1 M of precursor (silver nitrate) and 0.2 g of the metabolites obtained from ethanolic extract of Justicia adhatoda. Characterization of the nanoparticles was done by UV visible spectroscopy, fourier infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X ray diffraction (XRD) to confirm the structural and functional properties. Primary conformation of nanoparticles synthesis by UV visible spectroscopy revealed the notable absorption spectra at 425 nm with a wavelength shift around 450 nm, likely due to surface plasmon resonance excitation. SEM analysis showed spherical, monodisperse, nano scale particles with a size range of 50-60 nm. Crystaline phase of the synthesized nanoparticles was confirmed by x ray diffraction studies which showed the distinct peaks at (2θ) 27.90, 32.20, 46.30, 54.40, and 67.40, corresponding to (111), (200), (220), (222), and (311) planes of nano scale silver. The biocompatibility of these nanoparticles was assessed through zebrafish embryonic toxicity study which showed more than 90 % of embryos were alive and healthy. No marked changes on the blood cells also confirmed best hemocompatibility of the nanoparticles. Synthesized nanoparticles thus obtained were fabricated on the urinary catheter and the fabrication was confirmed by FTIR and SEM analysis. Notable changes in the absorption peaks, uniform coating and embedding of silver nanoparticles studied by FTIR and SEM analysis confirmed the fabrication of silver nanoparticles. The coated catheters demonstrated significant antibacterial activity against pathogenic bacterial strains, including E. coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853. Anti-biofilm studies, conducted using a modified microtiter plate crystal violet assay, revealed effective inhibition of both bacterial adhesion and biofilm development. 85 % of biofilm inhibition was recorded against both the tested strains. The coating method presented in this study shows promise for enhancing infection resistance in commonly used medical devices like urinary catheters, thus addressing device-associated infections.}, }
@article {pmid39325551, year = {2024}, author = {Rafe Hatshan, M and Perianaika Matharasi Antonyraj, A and Marunganathan, V and Rafi Shaik, M and Deepak, P and Thiyagarajulu, N and Manivannan, C and Jain, D and Melo Coutinho, HD and Guru, A and Arockiaraj, J}, title = {Synergistic Action of Vanillic Acid-Coated Titanium Oxide Nanoparticles: Targeting Biofilm Formation Receptors of Dental Pathogens and Modulating Apoptosis Genes for Enhanced Oral Anticancer Activity.}, journal = {Chemistry &amp; biodiversity}, volume = {}, number = {}, pages = {e202402080}, doi = {10.1002/cbdv.202402080}, pmid = {39325551}, issn = {1612-1880}, support = {RSP2024R222//King Saud University, Riyadh, Saudi Arabia/ ; }, abstract = {The prevalence of bacterial and fungal infections is caused by S. aureus, S. mutans, E. faecalis, and Candida albicans are often associated with dental illnesses. In the present study, a unique strategy was used to combat these diseases by fabricating titanium dioxide nanoparticles (TiO2 NPs) conjugated with the plant-based molecule vanillic acid (VA). To confirm the structural characterization of the synthesized VA-TiO2 NPs, an extensive analysis was carried out utilizing methods such as SEM, FTIR, and XRD. Assessments for scavenging reactive oxygen species were performed to evaluate its antioxidant capability. Furthermore, a zone of inhibition test targeting pathogenic oral bacteria was used to assess the antibacterial efficacy of VA-TiO2 NPs. Molecular modeling investigations were performed to better understand the interactions among vanillic acid and dental pathogen receptors using the Autodock program. The findings indicated that VA-TiO2 NPs exhibited strong free radical scavenging activity. Additionally, they showed excellent antibacterial action towards dental pathogens, with a minimum inhibition level of 60 μg/mL. Furthermore, at doses of 15 μg/mL, 30 μg/mL, 60 μg/mL, and 120 μg/mL, VA-TiO2 NPs demonstrated concentration-dependent apoptotic impacts on human oral carcinoma cells. Apoptotic gene over-expression was identified by the molecular perspectives that revealed the anticancer mechanism of VA-TiO2 NPs on KB cells. This study highlights the promising suitability of VA-TiO2 NPs for dental applications due to their robust antioxidant, anticancer, and antimicrobial characteristics. These nanoparticles present an evident prospect for addressing oral pathogen challenges and improving overall oral health.}, }
@article {pmid39325271, year = {2024}, author = {Kamali, M and Ghaderi, A and Tamimi, P and Firooz, A and Nasiri Kashani, M and Ayatollahi, A and Valizadeh, F and Fattahi, M and Fattahi, M}, title = {Reactive oxygen species-inducing itraconazole and its anti-biofilm activity against resistant Candida parapsilosis sensu lato biofilm cells isolated from patients with recalcitrant onychomycosis.}, journal = {Archives of dermatological research}, volume = {316}, number = {9}, pages = {642}, pmid = {39325271}, issn = {1432-069X}, mesh = {*Itraconazole/pharmacology ; Humans ; *Biofilms/drug effects ; *Reactive Oxygen Species/metabolism ; *Onychomycosis/drug therapy/microbiology ; *Antifungal Agents/pharmacology ; *Drug Resistance, Fungal/drug effects ; *Candida parapsilosis/drug effects/isolation &amp; purification ; Apoptosis/drug effects ; Microbial Sensitivity Tests ; Female ; Nails/microbiology/drug effects ; }, abstract = {Candida parapsilosis was introduced as the second most responsible for nail involvement. The colonization of biotic and abiotic surfaces by Candida spp. can result in the formation of biofilms, which possess a high level of resistance to typical antifungal agents. Since Candida spp. can produce biofilm mass on the surface of the nails, dermatologists should consider appropriate antifungals to eliminate both the planktonic and biofilm cells. The aim of this research was to determine the antifungal efficacy of itraconazole against C. parapsilosis sensu lato biofilm formations, in addition to its static effects. Ten C. parapsilosis sensu lato isolates were enrolled in this study. The use of itraconazole results in the accumulation of reactive oxygen species (ROS) during treatment. In order to verify the correlation between ROS and itraconazole-induced cell death, the viability of cells was analyzed by administering the ROS scavenger Ascorbic acid. The apoptotic features of itraconazole were analyzed using the Annexin V-FITC method. Based on current data, it was found that the generation of intracellular stresses by itraconazole is not observed in cells upon ROS inhibition, emphasizing the importance of intracellular ROS in the apoptotic mechanism of itraconazole. Targeting the oxidative defense system is a powerful point to use ROS-inducing antifungals as a superior choice for more effective therapies in case of recalcitrant onychomycosis.}, }
@article {pmid39324454, year = {2024}, author = {Pradhan, A and Shrestha, K and Aryal, S and Shrestha, S}, title = {Dental Biofilm Accumulation and Gingival Health of Teeth with Fixed Single Prosthesis Fabricated by Various Prosthetic Materials.}, journal = {Kathmandu University medical journal (KUMJ)}, volume = {22}, number = {85}, pages = {27-30}, pmid = {39324454}, issn = {1812-2078}, mesh = {Humans ; Female ; Male ; Adult ; Cross-Sectional Studies ; Middle Aged ; *Biofilms ; *Dental Plaque ; Aged ; Periodontal Index ; Crowns ; Ceramics ; Dental Plaque Index ; Young Adult ; Gingivitis ; Gingiva ; }, abstract = {Background Periodontal health plays an important role in maintaining the health of natural teeth as well as in the success of all dental procedures. Fixed single prosthesis (dental crown) can be fabricated with different types of prosthetic restorative materials like Metal, Ceramic, Ceramic fused to metal. These different materials have different affinity for plaque accumulation leading to the development of gingival inflammation and periodontal disease. Objective To determine the amount of Plaque accumulation and gingival health of teeth with a fixed single prosthesis fabricated by various Prosthetic materials. Method This quantitative cross-sectional study was carried out from July 2021 to March 2022. The patients who visited the hospital after six months of use of the prosthesis enrolled and were categorized into three groups according to the material used for the prosthesis metal, ceramic, and metal-ceramic. The periodontal condition was assessed using the plaque index and gingival index. Result A total of 136 patients (78 female and 58 male) were enrolled in the study, with a mean age of 39.44 ± 16.23 years (Range 19 - 70 years). There were 47 patients with ceramic crowns, 39 patients with metallic, and 50 patients with metal ceramic crowns. The mean plaque index of metal, ceramic, and metal-ceramic crowns was found 1.15 ± 0.546, 0.86 ± 0.479, and 0.93 ± 0.498 respectively. Similarly, the mean gingival index of metal, ceramic, and metal-ceramic crown were 1.22 ± 0.56, 0.91 ± 0.48, and 1.09 ± 0.55 respectively. Conclusion The dental biofilm (plaque) accumulation and hence gingival inflammation is less in ceramic crowns than in metal and metal-ceramic crowns.}, }
@article {pmid39323765, year = {2024}, author = {Du, T and Cao, J and Zhang, Z and Xiao, Z and Jiao, J and Song, Z and Du, X and Wang, S}, title = {Thermo-responsive cascade antimicrobial platform for precise biofilm removal and enhanced wound healing.}, journal = {Burns &amp; trauma}, volume = {12}, number = {}, pages = {tkae038}, pmid = {39323765}, issn = {2321-3868}, abstract = {BACKGROUND: Bacterial infection, tissue hypoxia and inflammatory response can hinder infected wound repair. This study aimed to develop a multifunctional specific therapeutic photo-activated release nanosystem [HMPB@MB@AuNPs@PMB@HA (HMAPH)] by loading photosensitizer methylene blue (MB) into hollow mesoporous Prussian blue nanostructures and modifying the surface with gold particles, polymyxin B (PMB) and hydrophilic hyaluronic acid.<br><br>METHODS: The HMAPH was characterized using transmission electron microscopy, UV-vis, Fourier-transform infrared spectroscopy, X-ray diffraction and X-ray photon spectroscopy. The photothermal performance, iron ion release and free radical generation of the HMAPH were measured under different conditions to investigate its thermo-responsive cascade reaction. The antibacterial ability of HMAPH was investigated using live/dead fluorescence tests. The morphology and membrane integrity of Pseudomonas aeruginosa (P. aeruginosa) were investigated using transmission electron microscopy. The anti-biofilm activity of HMAPH was evaluated using crystal violet and SYBR Green I staining. Finally, we established a mouse model of a skin wound infected by P. aeruginosa to confirm the in vivo effectiveness of HMAPH. We used immunofluorescent staining, hematoxylin-eosin staining, Masson staining and enzyme-linked immunosorbent assay to examine whether HMAPH promoted wound healing and reduced inflammatory damage.<br><br>RESULTS: In this study, hyaluronic acid was decomposed under the action of hyaluronidase. Also, the exposed nanomaterials specifically bound to the outer membrane of P. aeruginosa through PMB to increase the membrane sensitivity to photodynamic treatment. Under dual-light irradiation, a large amount of iron ions released by HMAPH underwent a Fenton reaction with H2O2 in bacteria to generate hydroxyl radicals (&#x2022;OH), enabling direct killing of cells by hyperthermia. Additionally, the photodynamic activity of MB released by photo-induced activation led to the generation of reactive oxygen species, achieving synergistic and effective inhibition of P. aeruginosa. HMAPH also inhibited biofilm formation and downregulated the expression of virulence factors. In vivo experiments revealed that HMAPH accelerated the healing of P. aeruginosa-infected wounds by promoting angiogenesis and skin regeneration, inhibiting the inflammatory response and promoting M1 to M2 polarization.<br><br>CONCLUSIONS: Our study proposed a strategy against bacteria and biofilms through a synergistic photothermal-photodynamic-Fenton reaction, opening up new prospects for combating biofilm-associated infections.}, }
@article {pmid39322446, year = {2024}, author = {Kim, HS and Kim, M and Kim, Y and Shin, HH and Lee, SW and Ryu, JH}, title = {Antimicrobial adhesive self-healing hydrogels for efficient dental biofilm removal from periodontal tissue.}, journal = {Dental materials : official publication of the Academy of Dental Materials}, volume = {40}, number = {11}, pages = {1970-1980}, doi = {10.1016/j.dental.2024.09.012}, pmid = {39322446}, issn = {1879-0097}, mesh = {*Biofilms/drug effects ; *Hydrogels/chemistry/pharmacology ; *Porphyromonas gingivalis/drug effects ; *Alginates/chemistry ; *Tannins/chemistry/pharmacology ; Boronic Acids/chemistry/pharmacology ; Humans ; Anti-Infective Agents/pharmacology/chemistry ; Materials Testing ; Anti-Bacterial Agents/pharmacology/chemistry ; Minocycline/pharmacology/chemistry ; Biocompatible Materials/chemistry/pharmacology ; }, abstract = {OBJECTIVES: Oral biofilms, including pathogens such as Porphyromonas gingivalis, are involved in the initiation and progression of various periodontal diseases. However, the treatment of these diseases is hindered by the limited efficacy of many antimicrobial materials in removing biofilms under the harsh conditions of the oral cavity. Our objective is to develop a gel-type antimicrobial agent with optimal physicochemical properties, strong tissue adhesion, prolonged antimicrobial activity, and biocompatibility to serve as an adjunctive treatment for periodontal diseases.<br><br>METHODS: Phenylboronic acid-conjugated alginate (Alg-PBA) was synthesized using a carbodiimide coupling agent. Alg-PBA was then combined with tannic acid (TA) to create an Alg-PBA/TA hydrogel. The composition of the hydrogel was optimized to enhance its mechanical strength and tissue adhesiveness. Additionally, the hydrogel's self-healing ability, erosion and release profile, biocompatibility, and antimicrobial activity against P. gingivalis were thoroughly characterized.<br><br>RESULTS: The Alg-PBA/TA hydrogels, with a final concentration of 5&#xa0;wt% TA, exhibited both mechanical properties comparable to conventional Minocycline gel and strong tissue adhesiveness. In contrast, the Minocycline gel demonstrated negligible tissue adhesion. The Alg-PBA/TA hydrogel also retained its rheological properties under repeated 5 kPa stress owing to its self-healing capability, whereas the Minocycline gel showed irreversible changes in rheology after just one stress cycle. Additionally, Alg-PBA/TA hydrogels displayed a sustained erosion and TA release profile with minimal impact on the surrounding pH. Additionally, the hydrogels exhibited potent antimicrobial activity against P. gingivalis, effectively eliminating its biofilm without compromising the viability of MG-63 cells.<br><br>SIGNIFICANCE: The Alg-PBA/TA hydrogel demonstrates an optimal combination of mechanical strength, self-healing ability, tissue adhesiveness, excellent biocompatibility, and sustained antimicrobial activity against P. gingivalis. These attributes make it superior to conventional Minocycline gel. Thus, the Alg-PBA/TA hydrogel is a promising antiseptic candidate for adjunctive treatment of various periodontal diseases.}, }
@article {pmid39322184, year = {2024}, author = {Chavez-Manini, CA and Reza-López, SA and Arzate-Quintana, C and Quiñonez-Flores, CM and Favila-Pérez, MA and Camarillo-Cisneros, J and Castillo-González, AR}, title = {Effect of electric current in viability, biofilm formation and antibiotic resistance of Pseudomonas aeruginosa: A systematic review.}, journal = {Indian journal of medical microbiology}, volume = {52}, number = {}, pages = {100735}, doi = {10.1016/j.ijmmb.2024.100735}, pmid = {39322184}, issn = {1998-3646}, mesh = {*Pseudomonas aeruginosa/drug effects/physiology ; *Biofilms/drug effects/growth &amp; development ; *Electricity ; *Microbial Viability/drug effects ; *Anti-Bacterial Agents/pharmacology ; Humans ; Electrodes ; Drug Resistance, Bacterial ; Microbial Sensitivity Tests ; }, abstract = {BACKGROUND: The bactericidal effect of electric current has been studied in various microorganisms such as Pseudomonas aeruginosa. The objective of this review is to identify the experimental parameters with the greatest antibacterial effect in the shortest time.<br><br>METHODS: Literature search was conducted in the databases PubMed, Science Direct, and Google Scholar. Only original articles published between 2014 and 2023 were included, where the effect of electric current on viability, biofilm formation, and/or antibiotic resistance in P. aeruginosa was analyzed. Quality control criteria considered included specifying control and experimental groups, replicates performed, experimental parameters, and study limitations.<br><br>RESULTS: Ten studies were included, which involved the strains Xen5, Xen41, PAO1 persistent cells, and PA14. An average reduction of 3.5 log in biofilm formation was observed in the included studies. The electric current parameters that achieved the greatest effect were 500&#xa0;&#x3bc;A DC with platinum electrodes for 4 days [5.2-5.5 log], 200&#xa0;&#x3bc;A intermittent with titanium electrodes for 4 days [4.99 log], and 150&#xa0;&#xb1;&#xa0;60&#xa0;&#x3bc;A with silver electrodes for 24&#xa0;h [4 log]. Complete eradication of PAO1 persistent cells was achieved in 1&#xa0;h with a treatment of 70 &#x3bc;A/cm2 DC followed by 1.5&#xa0;&#x3bc;g/mL tobramycin for 1&#xa0;h each.<br><br>CONCLUSIONS: The bactericidal effect of electric current is proportional to the exposure time and current intensity. The electrode material influences the effectiveness of the treatment, possibly because of redox reactions, while differences are observed in the effect on the cell membrane and gene expression when using metallic or carbon electrodes, suggesting differences in the mechanism of action.}, }
@article {pmid39321970, year = {2024}, author = {Ashkar Daw, M and Azrad, M and Peretz, A}, title = {Associations between biofilm formation and virulence factors among clinical Helicobacter pylori isolates.}, journal = {Microbial pathogenesis}, volume = {196}, number = {}, pages = {106977}, doi = {10.1016/j.micpath.2024.106977}, pmid = {39321970}, issn = {1096-1208}, mesh = {*Biofilms/growth &amp; development ; *Helicobacter pylori/genetics/drug effects/pathogenicity/isolation &amp; purification/physiology ; *Virulence Factors/genetics ; Humans ; *Bacterial Proteins/genetics/metabolism ; *Helicobacter Infections/microbiology ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; *Genotype ; *Antigens, Bacterial/genetics/metabolism ; *Urease/metabolism ; Clarithromycin/pharmacology ; Drug Resistance, Bacterial ; Levofloxacin/pharmacology ; Amoxicillin/pharmacology ; Tetracycline/pharmacology ; Rifampin/pharmacology ; Metronidazole/pharmacology ; }, abstract = {INTRODUCTION: Helicobacter pylori (H. pylori) causes several gastrointestinal diseases. Its virulence factors contributing to disease development include biofilm formation, cytotoxin-associated gene A (CagA) and vacuolating cytotoxin A (VacA) proteins that induce host tissue damage. In addition, urease activity enables H. pylori growth in the gastric acidic environment. This work aimed to characterize bacterial factors associated with biofilm production among 89 clinical H. pylori isolates, collected from patient gastric biopsies.<br><br>METHODS: Biofilm production was detected using the crystal violet method. PCR was performed to determine vacA genotype (s1m1, s1m2, s2m1 and s2m2) and cagA gene presence. Urease activity was measured via the phenol red method. Susceptibility to six antibiotics was assessed by the Etest method.<br><br>RESULTS: Most H. pylori isolates produced biofilm. No association was found between biofilm-formation capacity and cagA presence or vacA genotype. Urease activity levels varied across isolates; no association was found between biofilm-formation and urease activity. Clarithromycin resistance was measured in 49&#xa0;% of the isolates. Isolates susceptible to tetracycline were more commonly strong biofilm producers. In contrast, a significantly higher rate of strong biofilm producers was observed among resistant isolates to amoxicillin, levofloxacin and rifampicin, compared to susceptible isolates. Non-biofilm producers were more common among isolates sensitive to rifampicin and metronidazole, compared to resistant isolates.<br><br>CONCLUSIONS: Further studies are needed to understand the factors that regulate biofilm production in order to search for treatments for H. pylori biofilm destruction.}, }
@article {pmid39321968, year = {2024}, author = {Costa, MLVA and Neto, MCS and Fialho, PHDS and Costa, SCR and Araújo-Nobre, AR and Lopes, AP and Meneses, AKS and de Lima, SG and Vale, GC and Soares, MJDS and de Carvalho, ALM and Quelemes, PV}, title = {Effect of zinc oxide-eugenol endodontic paste on planktonic aggregates and biofilm of Enterococcus faecalis - An atomic force microscopy evaluation.}, journal = {Microbial pathogenesis}, volume = {196}, number = {}, pages = {106965}, doi = {10.1016/j.micpath.2024.106965}, pmid = {39321968}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Enterococcus faecalis/drug effects/ultrastructure ; *Microscopy, Atomic Force ; Animals ; Cattle ; Spectroscopy, Fourier Transform Infrared ; Plankton/drug effects ; Anti-Bacterial Agents/pharmacology ; Gas Chromatography-Mass Spectrometry ; Eugenol/pharmacology ; Zinc Oxide-Eugenol Cement/pharmacology ; Dentin/drug effects/microbiology ; Root Canal Filling Materials/pharmacology ; }, abstract = {OBJECTIVE: This work aimed to evaluate the in vitro effect of zinc oxide-eugenol paste (ZOE) on planktonic aggregates (EfPA) and biofilm (EfBio) of Enterococcus faecalis, focusing on their morphological aspects observed and analyzed using atomic force microscopy (AFM).<br><br>DESIGN: The eugenol and paste were characterized by Gas Chromatography coupled with Mass Spectrometry (GC-MS) and Fourier Transform Infrared Spectroscopy (FTIR), respectively. The effect of ZOE on EfPA and EfBio was evaluated by a direct-contact test through colony counting and crystal violet staining protocol. AFM images of untreated and treated EfPA and EfBio growth on bovine dentin were obtained to analyze the morphological damage caused by the treatments.<br><br>RESULTS: The characterization showed high purity in the eugenol composition and chemical interaction between the components of the paste. A bactericidal effect on aggregates was observed after 6&#xa0;h of exposure, and on biofilm after 24&#xa0;h of treatment (p&#xa0;<&#xa0;0.001). A disruptive effect on the biofilm was also evident. AFM images revealed the formation of EfPA, with a notable presence of an exopolysaccharide matrix. After 6&#xa0;h of ZOE treatment, there was a significant increase in the size and surface roughness profile of treated cells (p&#xa0;<&#xa0;0.05). Loss of typical cell morphology was observed after 24&#xa0;h. The effect on the biofilm showed a tendency towards a less condensed biofilm pattern in the treated group, with no differences in surface roughness.<br><br>CONCLUSION: ZOE presents bactericidal action on EfPA and EfBio, promoting significant morphological changes after treatment, especially in the aggregates.}, }
@article {pmid39321727, year = {2024}, author = {Wen, C and Li, Q and Zhu, D and Zhong, M and Zhu, S and Xu, H and Li, C and Zhu, S and Caiola, N and Chen, L and Luo, X}, title = {Biofilm-mediated heavy metal bioaccumulation and trophic transfer in a mining-contaminated river.}, journal = {Water research}, volume = {267}, number = {}, pages = {122487}, doi = {10.1016/j.watres.2024.122487}, pmid = {39321727}, issn = {1879-2448}, mesh = {*Metals, Heavy ; *Biofilms ; *Rivers ; *Food Chain ; *Mining ; *Water Pollutants, Chemical/metabolism ; Animals ; Bioaccumulation ; Environmental Monitoring ; Fishes ; }, abstract = {Biofilms, essential for material circulation and energy flow in aquatic ecosystems, markedly enrich heavy metals in water environments. However, the impact of these accumulated metals on organisms feeding on biofilms remains poorly unknown. This study involved a year-long seasonal survey along the Bijiang River, located next to Asia's largest lead (Pb)-zinc (Zn) mine, conducted to investigate the role of biofilms in nutrient and metal transfer in food webs. In total, 355 biotic and abiotic samples, including water, biofilms, and aquatic biota, were analyzed for the presence of eight heavy metals (arsenic [As], cadmium, chromium, copper, Pb, nickel, Zn, and iron) as well as stable carbon (δ[13]C) and nitrogen (δ[15]N) isotopes. Wide ranges of δ[13]C and δ[15]N values indicated diverse dietary carbon sources and trophic positions in the Bijiang River (maximum trophic level: 4.28). A Bayesian mixing model revealed that periphytic biofilms were the dominant basal carbon source, especially in spring, whereas in summer, consumers exploited more diverse food sources, possibly because feeding on spring biofilms enhanced predator feeding efficiency. Metals tended to be biodiluted along food chains owing to their higher concentrations in biofilms and benthic organisms as well as their chemical forms. Although diet did not significantly affect heavy metal accumulation in fish, those relying on biofilms as the main carbon source showed significantly higher As (p = 0.048) and Pb (p = 0.007) levels compared with those relying on C4 plants. Overall, this study highlights the critical role of periphytic biofilms in nutrient and metal dynamics in aquatic food webs.}, }
@article {pmid39321640, year = {2025}, author = {Yu, W and Wang, Q and Liu, Z and Gan, H and Wu, Q and Guo, N and Zeng, W and Li, S and Liu, Y}, title = {Metal-phenolic network crosslinked nanogel with prolonged biofilm retention for dihydroartemisinin/NIR synergistically enhanced chemodynamic therapy.}, journal = {Journal of colloid and interface science}, volume = {678}, number = {Pt C}, pages = {841-853}, doi = {10.1016/j.jcis.2024.09.168}, pmid = {39321640}, issn = {1095-7103}, mesh = {*Biofilms/drug effects ; *Artemisinins/chemistry/pharmacology/administration &amp; dosage ; *Nanogels/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; Hyaluronic Acid/chemistry/pharmacology ; Tannins/chemistry/pharmacology ; Animals ; Staphylococcus aureus/drug effects ; Mice ; Iron/chemistry ; Particle Size ; Microbial Sensitivity Tests ; Polyethylene Glycols/chemistry/pharmacology ; Drug Liberation ; Surface Properties ; Polyethyleneimine ; }, abstract = {Chemodynamic therapy (CDT) is emerging as a promising treatment for biofilm infections. However, its effectiveness is significantly hindered by several factors: the body's stable temperature, a limited supply of Fe[2+] ions, and inadequate endogenous levels of H2O2 at the infection sites. Herin, our study introduces MPN-crosslinked hyaluronic acid (HA) nanogels as an effective strategy for treating biofilm-associated infections. The DHA@HA-TA/Fe (DHTF) nanogel is synthesized through the coordination reaction between Fe[2+] ions and tannic acid (TA)-modified HA, with dihydroartemisinin (DHA) encapsulated within the structure. DHTF exhibits pH-/hyaluronidase-responsiveness in the biofilm infection microenvironment, enabling sustained release of DHA as a substitute for H2O2 and Fe[2+] for CDT. The incorporation of Fe[2+]/TA-based MPN and DHA within the nanogels enables photothermal/DHA dually-enhanced CDT, facilitating efficient disruption of biofilm matrices and bacterial eradication through boosting reactive oxygen species production. In vivo studies demonstrate that DHTF exhibit prolonged retention within biofilms. This ensures a sustained release of therapeutic agents and continuous anti-biofilm activity. Eventually, both in vitro and in vivo evaluations consistently confirm the significant anti-biofilm capacity of DHTF. Our findings highlight the potential of DHTF as a promising nanomedicine for biofilm-related infections, offering efficient treatment strategies that could improve clinical management of these challenging conditions.}, }
@article {pmid39319552, year = {2024}, author = {Antunes Filho, S and Pizzorno Backx, B and Foguel, D}, title = {Green nanotechnology in phytosynthesis and its efficiency in inhibiting bacterial biofilm formation: implications for medicine.}, journal = {Biofouling}, volume = {40}, number = {10}, pages = {645-659}, doi = {10.1080/08927014.2024.2407036}, pmid = {39319552}, issn = {1029-2454}, mesh = {*Biofilms/drug effects ; *Metal Nanoparticles/chemistry ; *Nanotechnology/methods ; *Green Chemistry Technology ; Anti-Bacterial Agents/pharmacology/chemistry ; Bacteria/drug effects ; Silver/pharmacology/chemistry ; Gold/chemistry ; }, abstract = {Nanotechnology is used in several biomedical applications, including antimicrobial and antibiofilm applications using nanomaterials. Bacterial biofilm varies according to the strain; the matrix is very strong and resistant. In this sense, phytosynthesis is an important method for combating bacterial biofilms through the use of metallic nanoparticles (silver, gold, or copper) with increased marketing and technical-scientific potential. In this review, we seek to gather the leading publications on the use of phytosynthesized metallic nanoparticles against bacterial biofilms. Furthermore, this study aims to understand the main characteristics and parameters of these nanomaterials, their antibiofilm efficiency, and the presence or absence of cytotoxicity in these developed technologies.}, }
@article {pmid39319013, year = {2024}, author = {Muturi, P and Wachira, P and Wagacha, M and Mbae, C and Kavai, S and Muhammed, M and Gunn, JS and Kariuki, S}, title = {Fecal Shedding, Antimicrobial Resistance and In Vitro Biofilm formation on Simulated Gallstones by Salmonella Typhi Isolated from Typhoid Cases and Asymptomatic Carriers in Nairobi, Kenya.}, journal = {International journal of clinical microbiology}, volume = {1}, number = {2}, pages = {23-36}, pmid = {39319013}, issn = {2690-4721}, support = {R01 AI099525/AI/NIAID NIH HHS/United States ; R01 AI116917/AI/NIAID NIH HHS/United States ; }, abstract = {Typhoid fever, caused by the human restricted pathogen Salmonella Typhi, remains a major global public health concern. Even after successful treatment, approximately 3-5% of patients with typhoid fail to clear the bacteria within one year and become chronic carriers. Most typhoid carriers have gallstones in their gallbladder, and biofilm formation on gallstones is highly correlated with chronic carriage. This study's goal was to identify asymptomatic typhoid carriers in an endemic setting in Kenya, and to compare acute versus chronic isolates. A cohort of typhoid fever patients identified through blood and/or stool culture, and their household contacts, were followed up after treatment to detect longitudinal S. Typhi stool shedding. An abdominal ultrasound scan was used to identify individuals with gallstones. A total of 32 index patients and 32 household contacts were successfully followed-up. Gallstones were detected in 4 cases and 1 household contact. The duration of S. Typhi shedding was significantly longer in individuals with gallstones compared to those without, P<0.001. Eighty-three (83) S. Typhi strains were tested for susceptibility to commonly used antimicrobials and examined by in vitro biofilm formation assays. Out of 37 infected individuals, 32.4% had infections caused by multidrug resistant (MDR) S. Typhi strains and only 18.9% were infected by susceptible strains. Non-MDR strains formed significantly better biofilms in vitro than the MDR strains (P<0.001). This study provides data on S. Typhi chronic carriage that will influence public health approaches aimed at reducing typhoid transmission and the burden of infection.}, }
@article {pmid39318902, year = {2024}, author = {Raju, R and Prasad, AS and S, RK}, title = {Anti-inflammatory and Antioxidant Activity of Neem and Kirata-Induced Silver Nanoparticles Against Oral Biofilm: An In Vitro Study.}, journal = {Cureus}, volume = {16}, number = {8}, pages = {e67708}, pmid = {39318902}, issn = {2168-8184}, abstract = {Introduction Silver nanoparticles have been the most commonly used nanoparticles which could be integrated with plant extracts. The mutually beneficial interaction between neutral plant extracts and nanoparticles reduced the chemical toxicity while promoting synthesis. Azadirachta indica, widely known as the neem plant, has diverse medicinal compounds encompassing antibacterial, antiviral, antiprotozoal, insecticidal, antifungal, and antioxidant properties. Swertia chirata, known as Chirayata in India, stands out for its dual roles as a laxative and appetiser with pronounced antimicrobial and anti-inflammatory qualities. Hence, this study aimed to evaluate the anti-inflammatory and antioxidant properties of silver nanoparticles synthesized using Neem and Kirata extract. Materials and methods The plant extracts of Neem (Azadirachta indica) and Kirata (Swertia chirata) were obtained in powder form. It was later formulated into an extract and stored in a refrigerator at 4 degrees Celsius. The formulated extract of Neem and Kirata was then incorporated with silver nitrate to form a modified silver nanoparticle using a green synthesis approach. The anti-inflammatory activity of Neem and Kirata extract was tested using Bovine Serum Assay and Egg Albumin Assay. The antioxidant activity of the new herbal-formulated Ag nanoparticles was determined by the DPPH ((2,2-diphenyl-1-picrylhydrazyl) assay. Results Based on the anti-inflammatory assays, the Neem and Kirata-induced nanoparticles showed increasing levels of inhibition, while the standard showed slightly higher inhibition at 10, 20 and 30 µL. At 40 µL and 50 µL, both Kirata and Neem (Ag) and the standard showed high levels of inhibition, nearing 75% and above, with the standard consistently showing a marginally higher inhibition percentage. Based on the DPPH assay, the Neem Kirata-induced Ag nanoparticle showed a comparable or slightly higher inhibition percentage compared to the standard. Conclusion The study underscores the potential of Neem and Kirata herbal-based silver nanoparticles as effective anti-inflammatory and antioxidant agents. Future research directions should focus on refining nanoparticle synthesis, investigating mechanisms of action, and exploring additional therapeutic applications in the biomedical and pharmaceutical sectors.}, }
@article {pmid39318870, year = {2024}, author = {Allen-Taylor, D and Boro, G and Cabato, PM and Mai, C and Nguyen, K and Rijal, G}, title = {Staphylococcus epidermidis biofilm in inflammatory breast cancer and its treatment strategies.}, journal = {Biofilm}, volume = {8}, number = {}, pages = {100220}, pmid = {39318870}, issn = {2590-2075}, abstract = {Bacterial biofilms represent a significant challenge in both clinical and industrial settings because of their robust nature and resistance to antimicrobials. Biofilms are formed by microorganisms that produce an exopolysaccharide matrix, protecting function and supporting for nutrients. Among the various bacterial species capable of forming biofilms, Staphylococcus epidermidis, a commensal organism found on human skin and mucous membranes, has emerged as a prominent opportunistic pathogen, when introduced into the body via medical devices, such as catheters, prosthetic joints, and heart valves. The formation of biofilms by S. epidermidis on these surfaces facilitates colonization and provides protection against host immune responses and antibiotic therapies, leading to persistent and difficult-to-treat infections. The possible involvement of biofilms for breast oncogenesis has recently created the curiosity. This paper therefore delves into S. epidermidis biofilm involvement in breast cancer. S. epidermidis biofilms can create a sustained inflammatory environment through their metabolites and can break DNA in breast tissue, promoting cellular proliferation, angiogenesis, and genetic instability. Preventing biofilm formation primarily involves preventing bacterial proliferation using prophylactic measures and sterilization of medical devices and equipment. In cancer treatment, common modalities include chemotherapy, surgery, immunotherapy, alkylating agents, and various anticancer drugs. Understanding the relationship between anticancer drugs and bacterial biofilms is crucial, especially for those undergoing cancer treatment who may be at increased risk of bacterial infections, for improving patient outcomes. By elucidating these interactions, strategies to prevent or disrupt biofilm formation, thereby reducing the incidence of infections associated with medical devices and implants, can be identified.}, }
@article {pmid39318723, year = {2024}, author = {Alvim, ALS and Varoto, AA and Martins, E and Rigotti, MA and Ferreira, AM and Dodo, NB and Diniz, MO and Giroti, ALB and Carneiro, LM and Dos Santos Almeida Vaz, E and de Sousa, AFL and de Andrade, D}, title = {Impact of water quality on reprocessing equipment: Assessment of neurosurgical instruments cleaning and biofilm formation in hospital pipes.}, journal = {Journal of infection prevention}, volume = {25}, number = {5}, pages = {161-165}, pmid = {39318723}, issn = {1757-1774}, abstract = {BACKGROUND: The presence of contamination and microorganisms at any stage of processing renders a method unsafe, leading to a high risk of cross-transmission and cross-infection.<br><br>OBJECTIVE: The objective of this study was to assess the cleaning quality of aspirator instruments used in neurosurgical procedures.<br><br>METHODS: The experimental study was conducted at the materials and sterilization center, as well as the microbiology laboratory, of a philanthropic hospital in Brazil. A study protocol was implemented, which involved the analysis of 10 samples of Yasargil aspirators with varying dimensions. The samples were subjected to protein tests to detect the presence of organic matter and microbiological analysis. Descriptive statistics were used to analyze the data.<br><br>RESULTS: The results indicated that 40% of the instruments tested positive for protein after manual cleaning. Furthermore, after automated cleaning, samples showed an increased microbiological load, with Escherichia coli accounting for 20% and Klebsiella aerogenes for 10% of the identified microorganisms.<br><br>CONCLUSION: This study provides evidence of failures in the cleaning process of healthcare products and highlights the presence of biofilm in the pipes, thereby compromising the drinking water quality standard.}, }
@article {pmid39318525, year = {2024}, author = {Váczi, P and Čonková, E and Malinovská, Z}, title = {Synergistic effect of essential oils and chlorhexidine against planktonic and biofilm-forming cells of Malassezia pachydermatis.}, journal = {Veterinary and animal science}, volume = {26}, number = {}, pages = {100397}, pmid = {39318525}, issn = {2451-943X}, abstract = {Malassezia (M.) pachydermatis, is often associated with secondary infection of the skin and external auditory canal in dogs and cats. The treatment of Malassezia infections is based on the local application of antifungals often combined with antiseptics. Due to increased resistance of yeast to commonly used antimycotics, especially in biofilm-forming cells, the use of natural substances, e.g. plant essential oils, appears as a new promised option. In this study, the efficacy of selected plant essential oils (EO) - oregano, rosemary, bergamot, clove, cinnamon, and thyme - in combination with chlorhexidine on both planktonic and biofilm-forming cells of M. pachydermatis, was investigated. The checkerboard test was used to determine the effect of chlorhexidine combined with individual EOs. According to the FICI (fractional inhibitory concentration index) in planktonic cells, most combinations showed additive effect, except for thyme and rosemary EO, where a synergistic effect was found (33.3 % and 16.7 % respectively). In the biofilm-forming cells, a synergistic effect was noted in chlorhexidine combined with bergamot EO, recorded in 6 isolates (33.3 %), and with thyme and oregano EO, detected in 3 isolates (16.7 %). A significant decrease (p ˂ 0.05) was found in FIC (fractional inhibitory concentration) compared to MIC (minimum inhibitory concentration), for both planktonic and biofilm-forming cells. Based on the obtained results, we can conclude that the combination of chlorhexidine with EOs achieved better efficiency than when using each agent alone and made it possible to reduce the concentration of both, and a sufficient antifungal and antibiofilm effect was achieved in M. pachydermatis strains.}, }
@article {pmid39317617, year = {2024}, author = {Bao, HX and Wang, HL and Wang, ST and Sun, YL and Zhang, XN and Cheng, HY and Qian, ZM and Wang, AJ}, title = {Corrigendum to "Response of sulfur-metabolizing biofilm to external sulfide in element sulfur-based denitrification packed-bed reactor" [Environ. Res. 231 (2023) 116061].}, journal = {Environmental research}, volume = {262}, number = {Pt 1}, pages = {120001}, doi = {10.1016/j.envres.2024.120001}, pmid = {39317617}, issn = {1096-0953}, }
@article {pmid39317560, year = {2024}, author = {Ahirwar, P and Kozlovskaya, V and Pukkanasut, P and Nikishau, P and Nealy, S and Harber, G and Michalek, SM and Antony, L and Wu, H and Kharlampieva, E and Velu, SE}, title = {Polymer vesicles for the delivery of inhibitors of cariogenic biofilm.}, journal = {Dental materials : official publication of the Academy of Dental Materials}, volume = {40}, number = {11}, pages = {1937-1953}, pmid = {39317560}, issn = {1879-0097}, support = {R01 DE022350/DE/NIDCR NIH HHS/United States ; R03 DE025058/DE/NIDCR NIH HHS/United States ; R21 DE028349/DE/NIDCR NIH HHS/United States ; }, mesh = {*Biofilms/drug effects ; *Dental Caries/microbiology/drug therapy/prevention &amp; control ; Animals ; *Streptococcus mutans/drug effects ; Rats ; *Polymers/chemistry ; Anti-Bacterial Agents/pharmacology/chemistry ; Drug Delivery Systems ; Hydrogen-Ion Concentration ; Disease Models, Animal ; }, abstract = {OBJECTIVES: The goal of this study is to develop a novel drug delivery platform for the pH-responsive delivery of biofilm inhibitors as a potential avenue to prevent and treat dental caries.<br><br>METHODS: Biofilm and growth inhibition assays were performed in polystyrene microtiter 96-well plates. Docking analysis was performed using the reported GtfB +&#xa0;HA5 co-crystal structure (PDB code: 8fg8) in SeeSAR 13.0.1 software. Polymersome vesicles were assembled from poly(N-vinylpyrrolidone)8-block-poly(dimethylsiloxane)64-block-poly(N-vinylpyrrolidone)8 (PVPON8-PDMS64-PVPON8) triblock copolymer using a nanoprecipitation method. Microbiome analysis of biofilm inhibitors and the in vivo drug release and antivirulence activities of polymersome encapsulated inhibitors have been carried out in a S. mutans induced rat caries model.<br><br>RESULTS: Biofilm inhibitors for HA5 and HA6 have shown species-specific selectivity towards S. mutans and the ability to preserve the oral microbiome in a S. mutans induced dental caries model. The inhibitors were encapsulated into pH-responsive block copolymer vesicles to generate polymersome-encapsulated biofilm inhibitors, and their biofilm and growth inhibitory activities against S. mutans and representative strains of oral commensal streptococci have been assessed. A 4-week treatment of S. mutans UA159 infected gnotobiotic rats with 100&#xa0;&#xb5;M of polymersome-encapsulated biofilm inhibitor, PEHA5 showed significant reductions in buccal, sulcal, and proximal caries scores compared to an untreated control group.<br><br>SIGNIFICANCE: Taken together, our data suggests that the biofilm-selective therapy using the polymersome-encapsulated biofilm inhibitors is a viable approach for the prevention and treatment of dental caries while preserving the oral microbiome.}, }
@article {pmid39317234, year = {2024}, author = {Keller, S and LuTheryn, G and Gray, M and Lyons, B and Cleveland, RO and Stride, E and Coussios, CC}, title = {Quantitative evaluation of anti-biofilm cavitation activity seeded from microbubbles or protein cavitation nuclei by passive acoustic mapping.}, journal = {Physics in medicine and biology}, volume = {}, number = {}, pages = {}, doi = {10.1088/1361-6560/ad7f1a}, pmid = {39317234}, issn = {1361-6560}, abstract = {Bacterial biofilms represent a major challenge for effective antibiotic therapy as they confer physical and functional changes that protect bacteria from their surrounding environment. In this work, focused ultrasound in combination with cavitation nuclei was used to disrupt biofilms of Staphylococcus aureus and Pseudomonas aeruginosa, both of which are on the World Health Organization's priority list for new antimicrobial research. Approach: Single species biofilms were exposed to ultrasound (0.5 MHz centre frequency, 0.5-1.5 MPa peak rarefactional pressure, 200 cycle pulses, 5 Hz repetition frequency, 30 s duration), in the presence of two different types of cavitation nuclei. Quantitative passive acoustic mapping (PAM) was used to monitor cavitation emissions during treatment using a calibrated linear array. Main Results: It was observed that the cumulative energy of acoustic emissions during treatment was positively correlated with biofilm disruption, with differences between bacterial species attributed to differences in biofilm morphology. PCaN provided increased biofilm reduction compared to microbubbles due in large part to their persistence over the duration of ultrasound exposure. There was also good correlation between the spatial distribution of cavitation as characterized by PAM and the extent of biofilm disruption observed with microscopy. Significance: Collectively, the results from this work indicate the potential broad applicability of cavitation for eliminating biofilms of priority pathogens and the opportunity presented by Passive Acoustic Mapping for real-time monitoring of antimicrobial processes.}, }
@article {pmid39316962, year = {2024}, author = {Pousty, D and Ma, B and Mathews, C and Halanur, M and Mamane, H and Linden, KG}, title = {Biofilm inactivation using LED systems emitting germicidal UV and antimicrobial blue light.}, journal = {Water research}, volume = {267}, number = {}, pages = {122449}, doi = {10.1016/j.watres.2024.122449}, pmid = {39316962}, issn = {1879-2448}, mesh = {*Biofilms/radiation effects ; *Ultraviolet Rays ; *Disinfection/methods ; *Pseudomonas aeruginosa ; *Light ; Polycarboxylate Cement/chemistry ; Polyvinyl Chloride/chemistry ; Blue Light ; }, abstract = {Biofilms have been widely detected in water distribution and water storage systems posing potential risks to drinking water safety by harboring and shedding pathogens. Light-based disinfection methods, such as germicidal ultraviolet (UV) and antimicrobial blue light (aBL), could serve as non-chemical alternatives for biofilm control. This study investigated the inactivation of pure-culture Pseudomonas aeruginosa biofilms and mixed-culture biofilms using three distinct light-based disinfection methods: a low-pressure (LP) UV lamp emitting at 254 nm, a UV light emitting diode (LED) at 270 nm, and an aBL LED at 405 nm. The biofilms were developed on three commonly used materials including polycarbonate (PC), polytetrafluoroethylene (PTFE), and polyvinyl chloride (PVC), to assess the impact of surface characteristics on light-based biofilm inactivation. Our findings show that all selected devices can effectively inactivate pure-culture and mixed-culture biofilms. While both UV devices (LP UV lamp and UV LED) provided significant inactivation at lower fluences (>1 log reduction at 20 mJ/cm[2]), aBL LED achieved significant inactivation at higher fluences for pure culture (maximum log reduction of 3.8 ± 0.5 at > 200,000 mJ/cm[2]). Inactivation performance also varied with surface materials, likely attributed to different surface properties including roughness, hydrophobicity, and surface charge. This study provides important information on using light-based technologies for biofilm control and highlights the effect of surface materials on their inactivation performance.}, }
@article {pmid39315775, year = {2024}, author = {Laekas-Hameder, M and Daigle, F}, title = {Only time will tell: lipopolysaccharide glycoform and biofilm-formation kinetics in Salmonella species and Escherichia coli.}, journal = {Journal of bacteriology}, volume = {206}, number = {10}, pages = {e0031824}, pmid = {39315775}, issn = {1098-5530}, support = {RGPIN-2020-05233//Canadian Government | Natural Sciences and Engineering Research Council of Canada (NSERC)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Lipopolysaccharides/metabolism ; *Escherichia coli/genetics/metabolism/physiology ; *Salmonella/physiology/genetics/metabolism ; Kinetics ; Bacterial Adhesion ; }, abstract = {In Gram-negative bacteria, LPS (lipopolysaccharide) has been thoroughly characterized and has been shown to play a major role in pathogenesis and bacterial defense. In Salmonella and Escherichia coli, LPS also influences biofilm development. However, the overall role of LPS glycoform in biofilm formation has not been conclusively settled, as there is a lack of consensus on the topic. Some studies show that LPS mutants produce less biofilm biomass than the wild-type strains, while others show that they produce more. This review summarizes current knowledge of LPS biosynthesis and explores the impact of defective steps on biofilm-related characteristics, such as motility, adhesion, auto-aggregation, and biomass production in Salmonella and E. coli. Overall, motility tends to decrease, while adhesion and auto-aggregation phenotypes tend to increase in most LPS-mutant strains. Interestingly, biofilm biomass of various LPS mutants revealed a clear pattern dependent on biofilm maturation time. Incubation times of less than 24 h resulted in a biofilm-defective phenotype compared to the wild-type, while incubation exceeding 24 h led to significantly higher levels of biofilm production. This explains conflicting results found in reports describing the same LPS mutations. It is therefore critical to consider the effect of biofilm maturation time to ascertain the effects of LPS glycoform on biofilm phenotype. Underlying reasons for such changes in biofilm kinetics may include changes in signalling systems affecting biofilm maturation and composition, and dynamic LPS modifications. A better understanding of the role of LPS in the evolution and modification of biofilms is crucial for developing strategies to disperse biofilms.}, }
@article {pmid39315276, year = {2024}, author = {Korkus, J and Sałata, P and Thompson, SA and Paluch, E and Bania, J and Wałecka-Zacharska, E}, title = {The role of cydB gene in the biofilm formation by Campylobacter jejuni.}, journal = {Research square}, volume = {}, number = {}, pages = {}, pmid = {39315276}, issn = {2693-5015}, support = {R01 AI103267/AI/NIAID NIH HHS/United States ; R21 AI154078/AI/NIAID NIH HHS/United States ; }, abstract = {Campylobacter jejuni is a major cause of food- and water-borne bacterial infections in humans. A key factor helping bacteria to survive adverse environmental conditions is biofilm formation ability. Nonetheless, the molecular basis underlying biofilm formation by C. jejuni remains poorly understood. Around thirty genes involved in the regulation and dynamics of C. jejuni biofilm formation have been described so far. We applied random transposon mutagenesis to identify new biofilm-associated genes in C. jejuni strain 81-176. Of 1350 mutants, twenty-four had a decreased ability to produce biofilm compared to the wild-type strain. Some mutants contained insertions in genes previously reported to affect the biofilm formation process. The majority of identified genes encoded hypothetical proteins. In the library of EZ-Tn5 insertion mutants, we found the cydB gene associated with respiration that was not previously linked with biofilm formation in Campylobacter. To study the involvement of the cydB gene in biofilm formation, we constructed a non-marked deletion cydB mutant together with a complemented mutant. We found that the cydB deletion-mutant formed a weaker biofilm of loosely organized structure and lower volume than the parent strain. In the present study, we demonstrated the role of the cydB gene in biofilm formation by C. jejuni.}, }
@article {pmid39314881, year = {2024}, author = {Lee, H and Hwang, SH and Shin, H and Ha, NC and Wang, Q and Choi, SH}, title = {Identification and characterization of a small molecule BFstatin inhibiting BrpR, the transcriptional regulator for biofilm formation of Vibrio vulnificus.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1468567}, pmid = {39314881}, issn = {1664-302X}, abstract = {Many pathogenic bacteria form biofilms that are resistant to not only host immune defenses but also antibiotics, posing a need for the development of strategies to control biofilms. In this study, to prevent biofilm formation of the fulminating foodborne pathogen Vibrio vulnificus, chemical libraries were extensively screened to identify a small molecule inhibiting the activity of BrpR, a transcriptional regulator for biofilm genes. Accordingly, the BrpR inhibitor BFstatin [N1-(2-chloro-5-fluorophenyl)-N3-propylmalonamide], with a half-maximal effective concentration of 8.01 μM, was identified. BFstatin did not interfere with bacterial growth or exhibit cytotoxicity to the human epithelial cell line. BFstatin directly bound to BrpR and interrupted its binding to the target promoter DNAs of the downstream genes. Molecular dynamics simulation of the interaction between BFstatin and BrpR proposed that BFstatin modifies the structure of BrpR, especially the DNA-binding domain. Transcriptomic analyses revealed that BFstatin reduces the expression of the BrpR regulon including the cabABC operon and brp locus which contribute to the production of biofilm matrix of V. vulnificus. Accordingly, BFstatin diminished the biofilm levels of V. vulnificus by inhibiting the matrix development in a concentration-dependent manner. Altogether, BFstatin could be an anti-biofilm agent targeting BrpR, thereby rendering V. vulnificus more susceptible to host immune defenses and antibiotics.}, }
@article {pmid39312715, year = {2024}, author = {Jasim, ES and Kadhum, AS}, title = {Poly-Ether-Ether-Ketone versus dead-soft coaxial bonded retainers: a randomized clinical trial. Part 2: periodontal health and microbial biofilm assessment.}, journal = {European journal of orthodontics}, volume = {46}, number = {5}, pages = {}, doi = {10.1093/ejo/cjae048}, pmid = {39312715}, issn = {1460-2210}, mesh = {Adolescent ; Adult ; Female ; Humans ; Male ; Young Adult ; *Benzophenones ; *Biofilms ; Dental Calculus/microbiology ; *Dental Plaque Index ; *Ketones ; Orthodontic Appliance Design ; *Orthodontic Retainers ; *Periodontal Index ; Periodontal Pocket/microbiology ; Polyethylene Glycols ; Polymers ; Streptococcus mutans/isolation &amp; purification ; }, abstract = {BACKGROUND: Retainers have the potential to detrimentally impact periodontal health and contribute to tooth decay.<br><br>OBJECTIVES: To investigate periodontal health and bacterial biofilm related to Poly-Ether-Ether-Ketone (PEEK) fixed retainers as compared to Dead-soft coaxial fixed retainer (DSC).<br><br>TRIAL DESIGN: A two-arm parallel groups single-centre randomized clinical trial.<br><br>METHODS: The trial included patients whose orthodontic treatment was completed and required retainers. Participants were randomly assigned into two retainer groups: PEEK retainers, prepared by computer-aided design and manufacturing into 0.8&#xa0;mm wire form, and DSC retainers. The objectives included assessing periodontal health through plaque accumulation index (PI), bleeding on probing (BOP), periodontal pocket depth (PPD), gingival index (GI), calculus index (CI), and alveolar bone height (ABH) assessment. Biofilm assessment involved bacteriological screening of aerobic, facultative anaerobic, mutans streptococci, and lactobacilli. The periodontal indices and microbiological screening as well as were assessed at the debonding stage (T0), 1-month (T1), 3-month (T3), and 6-month (T6) after the commencement of the trial, except for the ABH, which was recorded using periapical radiograph at T0 and T6.<br><br>BLINDING: Single blinding of participants in addition to the bacteriological specialist.<br><br>RESULTS: Initially, the trial enrolled 46 participants, aged between 12 and 28 years, and were randomly assigned to two groups, with 23 participants in each group. Subsequently, one participant withdrew from the trial, resulting in a total of 45 participants whose data were analysed. Assessment of the periodontal indices, excluding the CI (P&#x2005;=&#x2005;.480), revealed statistically but not clinically significant differences between groups after 6-month of retention (P&#x2005;=&#x2005;.016 of PI, P&#x2005;=&#x2005;.020 of BOP, P&#x2005;=&#x2005;.05 of PPD, and P&#x2005;=&#x2005;.01 of GI). There was slight plaque accumulation, normal PPD (approximately 1&#xa0;mm), healthy to mild gingivitis with a GI of less than 1 and BOP was around 10%. Concerning the ABH, there was a noticeable reduction in its score after 6 months, particularly in the PEEK group, although the difference was not statistically significant (P&#x2005;=&#x2005;.102). Furthermore, the bacteriological viable count did not show any significant difference between the groups during the recall visits.<br><br>HARMS: There have been no reported negative consequences.<br><br>LIMITATIONS: Blinding the assessor of periodontal indices was not feasible due to the nature of the intervention. The trial follow-up duration was limited.<br><br>CONCLUSIONS: Both the PEEK and DSC retainers have comparable impacts on periodontal health and bacterial accumulation and composition during the retention period.<br><br>TRIAL REGISTRATION: NCT05557136.}, }
@article {pmid39312573, year = {2024}, author = {Carter, MD and Tran, TM and Cope-Arguello, ML and Weinstein, S and Li, H and Hendrich, CG and Prom, JL and Li, J and Chu, LT and Bui, L and Manikantan, H and Lowe-Power, TM and Allen, C}, title = {Lectins and polysaccharide EPS I have flow-responsive roles in the attachment and biofilm mechanics of plant pathogenic Ralstonia.}, journal = {PLoS pathogens}, volume = {20}, number = {9}, pages = {e1012358}, pmid = {39312573}, issn = {1553-7374}, mesh = {*Biofilms/growth &amp; development ; *Ralstonia/metabolism/physiology ; *Solanum lycopersicum/microbiology/metabolism ; *Lectins/metabolism/genetics ; *Polysaccharides, Bacterial/metabolism ; *Plant Diseases/microbiology ; Bacterial Adhesion/physiology ; Bacterial Proteins/metabolism/genetics ; Plant Roots/microbiology ; }, abstract = {Bacterial biofilm formation and attachment to hosts are mediated by carbohydrate-binding lectins, exopolysaccharides, and their interactions in the extracellular matrix (ECM). During tomato infection Ralstonia pseudosolanacearum (Rps) GMI1000 highly expresses three lectins: LecM, LecF, and LecX. The latter two are uncharacterized. We evaluated the roles in bacterial wilt disease of LecF, a fucose-binding lectin, LecX, a xylose-binding lectin, and the Rps exopolysaccharide EPS I. Interestingly, single and double lectin mutants attached to tomato roots better and formed more biofilm under static conditions in vitro. Consistent with this finding, static bacterial aggregation was suppressed by heterologous expression of lecFGMI1000 and lecXGMI1000 in other Ralstonia strains that naturally lack these lectins. Crude ECM from a ΔlecF/X double mutant was more adhesive than the wild-type ECM, and LecF and LecX increased Rps attachment to ECM. The enhanced adhesiveness of the ΔlecF/X ECM could explain the double mutant's hyper-attachment in static conditions. Unexpectedly, mutating lectins decreased Rps attachment and biofilm viscosity under shear stress, which this pathogen experiences in plant xylem. LecF, LecX, and EPS I were all essential for biofilm development in xylem fluid flowing through cellulose-coated microfluidic channels. These results suggest that under shear stress, LecF and LecX increase Rps attachment by interacting with the ECM and plant cell wall components like cellulose. In static conditions such as on root surfaces and in clogged xylem vessels, the same lectins suppress attachment to facilitate pathogen dispersal. Thus, Rps lectins have a dual biological function that depends on the physical environment.}, }
@article {pmid39312550, year = {2024}, author = {Korenaga, A and Miyaoka, T and Asami, H and Yamagami, Y and Yoshii, M and Tanaka, S and Nagao, T}, title = {Synergetic inhibitory effect of isopropyl methylphenol-based agents on biofilm formation by Streptococcus mutans.}, journal = {PloS one}, volume = {19}, number = {9}, pages = {e0310926}, pmid = {39312550}, issn = {1932-6203}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Streptococcus mutans/drug effects ; Drug Synergism ; Microbial Sensitivity Tests ; Gene Expression Regulation, Bacterial/drug effects ; Phenols/pharmacology ; Anti-Bacterial Agents/pharmacology ; Castor Oil ; Humans ; Polyethylene Glycols/pharmacology ; }, abstract = {Dental caries and periodontitis are the most common oral diseases in humans and the main causes of tooth loss. Streptococcus mutans is primarily responsible for dental caries and dental plaque, which are triggered by biofilm formation on the tooth surface. In this study, biofilm inhibition by 4-isopropyl-3-methylphenol (IPMP)-based agents, consisting of IPMP and polyoxyethylene-hydrogenated castor oil (POEHCO), was investigated in vitro. Notably, the use of POEHCO in addition to IPMP inhibited S. mutans biofilms more drastically than IPMP alone. Moreover, the effects of IPMP on the expression of biofilm-related genes (gtfB, gtfC, and gtfD) were examined using quantitative real-time PCR. IPMP at sub-minimum inhibitory concentrations significantly downregulated the expression of these genes. These results suggested that the inhibitory effects on biofilm formation were synergistically enhanced by the surfactant and antibiofilm activities of IPMP. Therefore, IPMP-based agents as dentifrices may be useful to prevent oral diseases originating from biofilms.}, }
@article {pmid39311590, year = {2024}, author = {Farha, AK and Habimana, O and Corke, H}, title = {Guanabenz acetate, an antihypertensive drug repurposed as an inhibitor of Escherichia coli biofilm.}, journal = {Microbiology spectrum}, volume = {12}, number = {11}, pages = {e0073824}, pmid = {39311590}, issn = {2165-0497}, support = {82150410458//MOST | National Natural Science Foundation of China (NSFC)/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Escherichia coli/drug effects ; *Drug Repositioning ; *Antihypertensive Agents/pharmacology ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; Humans ; Escherichia coli Infections/drug therapy/microbiology ; Escherichia coli Proteins/metabolism/genetics ; Bacterial Proteins/metabolism/genetics ; Cellulose/pharmacology/analogs &amp; derivatives ; }, abstract = {UNLABELLED: Biofilms formed by Escherichia coli are composed of amyloid curli and cellulose and have been shown to be linked to pathogenicity, antibiotic resistance, and chronic infections. Guanabenz acetate (GABE), an antihypertensive drug, was identified as a potential strategic repurposing drug due to its biofilm inhibitory properties following an extensive antimicrobial screening assay of 2,202 Food and Drug Administration-approved non-antibiotic agents. The results of this study provide insights into the effectiveness of GABE as a therapeutic alternative against E. coli biofilm-associated infectious diseases.<br><br>IMPORTANCE: Biofilm-associated bacterial infections are one of the major problems in medical settings. There are currently limited biofilm inhibitors available for clinical use. Guanabenz acetate, a drug used to treat high blood pressure, was found to be an effective anti-biofilm agent against Escherichia coli. Our results show that this drug can inhibit the production of cellulose and curli amyloid protein, which are the two main components of E. coli biofilms. Our findings highlight the possibility of repurposing a drug to prevent E. coli biofilm formation.}, }
@article {pmid39311303, year = {2024}, author = {Yaneva, B and Mutafchieva, M and Shentov, P and Tomov, G}, title = {Guided Biofilm Therapy for Management of "Desquamative Gingivitis"-Clinical Cases.}, journal = {Clinics and practice}, volume = {14}, number = {5}, pages = {1931-1939}, pmid = {39311303}, issn = {2039-7275}, abstract = {Background: Desquamative gingivitis is a clinical manifestation often associated with various mucocutaneous disorders, characterized by red, painful, and friable gingiva. It is predominantly seen in middle-aged to elderly females and is typically linked to autoimmune conditions such as lichen planus, pemphigoid, and pemphigus, among others. Due to the chronic pain and difficulty in maintaining personal oral hygiene, professional care becomes crucial. Methods: This article explores the application of guided biofilm therapy as a novel, gentle approach for managing desquamative gingivitis, focusing on three clinical cases. This therapy employs erythritol-based powders for biofilm removal, offering a less abrasive and more comfortable alternative to traditional mechanical plaque removal techniques. Results: The cases demonstrate the effectiveness of guided biofilm therapy in reducing discomfort and improving clinical outcomes in desquamative gingivitis patients, particularly those suffering from mucous membrane pemphigoid, pemphigus vulgaris, and oral lichen planus. Conclusions: The guided biofilm approach underscores the importance of tailored periodontal therapy in managing nonplaque-induced gingival lesions, improving patient compliance and oral health outcomes.}, }
@article {pmid39310685, year = {2023}, author = {Poje, G and Bilić, M and Dawidowsky, K and Kovač Bilić, L}, title = {BIOFILM AND HISTOPATHOLOGICAL GRADING OF MAXILLARY SINUS MUCOSA IN PATIENTS WITH ANTROCHOANAL POLYPS.}, journal = {Acta clinica Croatica}, volume = {62}, number = {3}, pages = {406-414}, pmid = {39310685}, issn = {1333-9451}, mesh = {Humans ; *Nasal Polyps/pathology/surgery/microbiology ; *Biofilms ; *Maxillary Sinus/microbiology/pathology/surgery ; Male ; Female ; Cross-Sectional Studies ; Adult ; Middle Aged ; Nasal Mucosa/microbiology/pathology ; Microscopy, Electron, Scanning ; Aged ; }, abstract = {The aim of this cross-sectional study was to determine the signs of biofilm in the maxillary sinus of patients with antrochoanal polyps (ACP), and status of the mucosa on which the biofilm occurred. Mucosal samples from maxillary sinus in 40 ACP patients who underwent endoscopic sinus surgery were analyzed histopathologically and by scanning electron microscopy. Results were compared with maxillary mucosa samples of 40 patients without endoscopic and radiological signs of sinus disease. The existence of biofilm and its relation to the degree of histopathological changes according to Terrier classification of chronic mucosal inflammation of maxillary sinus were statistically analyzed. Biofilm was detected in 23 of 40 (57.5%) ACP patients; the incidence was significantly lower in the control group (2/40, 5%). Biofilm was not found in type 1 mucosa according to Terrier classification. In conclusion, biofilm showed a significant incidence in the maxillary sinus mucosa of ACP patients (57.5%). Occasionally, biofilm can be found in patients with no signs of sinus disease, but not on histologically normal mucosa. Results of this study support the theory that biofilm formation does not represent the initial stage of the inflammatory process.}, }
@article {pmid39309319, year = {2024}, author = {Chen, H and Xia, A and Yan, H and Huang, Y and Zhu, X and Zhu, X and Liao, Q}, title = {Mass transfer in heterogeneous biofilms: Key issues in biofilm reactors and AI-driven performance prediction.}, journal = {Environmental science and ecotechnology}, volume = {22}, number = {}, pages = {100480}, pmid = {39309319}, issn = {2666-4984}, abstract = {Biofilm reactors, known for utilizing biofilm formation for cell immobilization, offer enhanced biomass concentration and operational stability over traditional planktonic systems. However, the dense nature of biofilms poses challenges for substrate accessibility to cells and the efficient release of products, making mass transfer efficiency a critical issue in these systems. Recent advancements have unveiled the intricate, heterogeneous architecture of biofilms, contradicting the earlier view of them as uniform, porous structures with consistent mass transfer properties. In this review, we explore six biofilm reactor configurations and their potential combinations, emphasizing how the spatial arrangement of biofilms within reactors influences mass transfer efficiency and overall reactor performance. Furthermore, we discuss how to apply artificial intelligence in processing biofilm measurement data and predicting reactor performance. This review highlights the role of biofilm reactors in environmental and energy sectors, paving the way for future innovations in biofilm-based technologies and their broader applications.}, }
@article {pmid39309185, year = {2024}, author = {To, D and Blanco Massani, M and Coraça-Huber, DC and Seybold, A and Ricci, F and Zöller, K and Bernkop-Schnürch, A}, title = {Antibiotic-Polyphosphate Nanocomplexes: A Promising System for Effective Biofilm Eradication.}, journal = {International journal of nanomedicine}, volume = {19}, number = {}, pages = {9707-9725}, pmid = {39309185}, issn = {1178-2013}, mesh = {*Biofilms/drug effects ; *Polyphosphates/chemistry/pharmacology ; *Colistin/pharmacology/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; Humans ; *Nanoparticles/chemistry ; *Micrococcus luteus/drug effects ; Particle Size ; Alkaline Phosphatase/metabolism ; Microbial Sensitivity Tests ; Cell Line ; Cell Survival/drug effects ; }, abstract = {PURPOSE: The eradication of bacterial biofilms poses an enormous challenge owing to the inherently low antibiotic susceptibility of the resident microbiota. The complexation of antibiotics with polyphosphate can substantially improve antimicrobial performance.<br><br>METHODS: Nanoparticular complexes of the model drug colistin and polyphosphate (CP-NPs) were developed and characterized in terms of their particle size and morphology, polydispersity index (PDI), zeta potential, and cytotoxicity. Enzyme-triggered monophosphate and colistin release from the CP-NPs was evaluated in the presence of alkaline phosphatase (AP). Subsequently, antimicrobial efficacy was assessed by inhibition experiments on planktonic cultures, as well as time-kill assays on biofilms formed by the model organism Micrococcus luteus.<br><br>RESULTS: The CP-NPs exhibited a spherical morphology with particle sizes <200 nm, PDI <0.25, and negative zeta potential. They showed reduced cytotoxicity toward two human cell lines and significantly decreased hemotoxicity compared with native colistin. Release experiments with AP verified the enzymatic cleavage of polyphosphate and subsequent release of monophosphate and colistin from CP-NPs. Although CP-NPs were ineffective against planktonic M. luteus cultures, they showed major activity against bacterial biofilms, outperforming native colistin treatment. Strongly elevated AP levels in the biofilm state were identified as a potential key factor for the observed findings.<br><br>CONCLUSION: Accordingly, polyphosphate-based nanocomplexes represent a promising tool to tackle bacterial biofilm.}, }
@article {pmid39309069, year = {2024}, author = {Ma, X and Wu, Z and Li, J and Yang, Y}, title = {Functional Study of desKR: a Lineage-Specific Two-Component System Positively Regulating Staphylococcus aureus Biofilm Formation.}, journal = {Infection and drug resistance}, volume = {17}, number = {}, pages = {4037-4053}, pmid = {39309069}, issn = {1178-6973}, abstract = {PURPOSE: Biofilms significantly contribute to the persistence and antibiotic resistance of Staphylococcus aureus infections. However, the regulatory mechanisms governing biofilm formation of S. aureus remain not fully elucidated. This study aimed to investigate the function of the S. aureus lineage-specific two-component system, desKR, in biofilm regulation and pathogenicity.<br><br>METHODS: Bioinformatic analysis was conducted to assess the prevalence of desKR across various S. aureus lineages and to examine its structural features. The impact of desKR on S. aureus pathogenicity was evaluated using in vivo mouse models, including skin abscess, bloodstream infection, and nasal colonization models. Crystal violet staining and confocal laser scanning microscopy were utilized to examine the impact of desKR on S. aureus biofilm formation. Mechanistic insights into desKR-mediated biofilm regulation were investigated by quantifying polysaccharide intercellular adhesin (PIA) production, extracellular DNA (eDNA) release, autolysis assays, and RT-qPCR.<br><br>RESULTS: The prevalence of desKR varied among different S. aureus lineages, with notably low carriage rates in ST398 and ST59 lineages. Deletion of desKR in NCTC8325 strain resulted in decreased susceptibility to &#x3b2;-lactam and glycopeptide antibiotics. Although desKR did not significantly affect acute pathogenicity, the &#x394;desKR mutant exhibited significantly reduced nasal colonization and biofilm-forming ability. Overexpression of desKR in naturally desKR-lacking strains (ST398 and ST59) enhanced biofilm formation, suggesting a lineage-independent effect. Phenotypic assays further revealed that the &#x394;desKR mutant showed reduced PIA production, decreased eDNA release, and lower autolysis rates. RT-qPCR indicated significant downregulation of icaA, icaD, icaB, and icaC genes, along with upregulation of icaR, whereas autolysis-related genes remained unchanged.<br><br>CONCLUSION: The desKR two-component system positively regulates S. aureus biofilm formation in a lineage-independent manner, primarily by modulating PIA synthesis via the ica operon. These findings provide new insights into the molecular mechanisms of biofilm formation in S. aureus and highlight desKR as a potential target for therapeutic strategies aimed at combating biofilm-associated infections.}, }
@article {pmid39306818, year = {2024}, author = {Szermer-Olearnik, B and Filik-Matyjaszczyk, K and Ciekot, J and Czarny, A}, title = {The Hydrophobic Stabilization of Pseudomonas aeruginosa Bacteriophage F8 and the Influence of Modified Bacteriophage Preparation on Biofilm Degradation.}, journal = {Current microbiology}, volume = {81}, number = {11}, pages = {370}, pmid = {39306818}, issn = {1432-0991}, support = {UMO-2019/03/X/NZ6/01710//Narodowym Centrum Nauki/ ; }, mesh = {*Pseudomonas aeruginosa/virology ; *Biofilms/growth &amp; development ; *Pseudomonas Phages/physiology ; *Hydrophobic and Hydrophilic Interactions ; 1-Octanol/chemistry ; Myoviridae/physiology/chemistry ; Bacteriophages/physiology/chemistry ; }, abstract = {The bacteriophage F8 belongs to the Myoviridae group of phages and is a pathogen of Pseudomonas aeruginosa. Since Pseudomonas aeruginosa is a multidrug-resistant opportunistic bacterium and can cause serious challenges for health services, studying the potential use of phages against them is a promising approach. Pseudomonas aeruginosa can be found on medical devices because bacteria can attach to surfaces and develop biofilms, which are difficult to eradicate because of their high resistance to environmental conditions and antimicrobial therapeutics. Phage therapy is becoming promising as an alternative for the treatment of antibiotic-resistant infections, but there is still a lack of standardized protocols approved by health organizations for possible use in the clinic. In our research, we focused on the potential use of 1-octanol, which was previously used by our team to develop a method for phage purification from bacterial lysate. 1-octanol is a fatty alcohol that is mostly used in the cosmetics industry, and its advantage is that it is approved by the FDA as a food additive. In this paper, we studied the protective properties of the addition of 1-octanol for storing phage liquid preparations. We demonstrated the stabilization effect of 1-octanol addition on F8 bacteriophage preparation during storage under various conditions. Interestingly, more effective biofilm reduction was observed after treatment with the purified bacteriophage and with 1-octanol addition compared to crude lysate.}, }
@article {pmid39306312, year = {2025}, author = {Javadi, K and Emadzadeh, MR and Mohammadzadeh Hosseini Moghri, SAH and Halaji, M and Parsian, H and Rajabnia, M and Pournajaf, A}, title = {Anti-biofilm and antibacterial effect of bacteriocin derived from Lactobacillus plantarum on the multidrug-resistant Acinetobacter baumannii.}, journal = {Protein expression and purification}, volume = {226}, number = {}, pages = {106610}, doi = {10.1016/j.pep.2024.106610}, pmid = {39306312}, issn = {1096-0279}, mesh = {*Biofilms/drug effects ; *Acinetobacter baumannii/drug effects ; *Lactobacillus plantarum/chemistry/genetics ; *Bacteriocins/pharmacology/chemistry/genetics/isolation &amp; purification ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Drug Resistance, Multiple, Bacterial/drug effects ; Microbial Sensitivity Tests ; Bacterial Proteins/genetics/pharmacology ; }, abstract = {This research examines the impact of bacteriocin derived from Lactobacillus plantarum PTCC 1745 on the biofilm formations of A. baumannii isolates. Bacteriocin derived from L. plantarum PTCC 1745 was obtained through ammonium sulfate precipitation, cation-exchange chromatography, and reversed-phase high-performance liquid chromatography (RP-HPLC). Testing for bacteriocin susceptibility has been conducted using the broth dilution method. The anti-biofilm activity of bacteriocin was evaluated using a microtiter plate method. Quantitative real-time PCR assay evaluated bap gene expression in bacteriocin-treated cells. According to SDS-PAGE, bacteriocin from L. plantarum has a 25-kDa apparent molecular weight. The MICs of bacteriocin ranged from 30 to 120 μg/mL, while the MBCs varied between 60 and 120 μg/mL. Compared to the non-treated group, strains bacteriocin-treated isolates had 59 % less ability to form biofilm. The mean relative expression of the bap gene among the MDR A. baumannii isolates decreased by 52 % compared to the untreated control. This study demonstrated that bacteriocin derived from L. plantarum PTCC 1745 had antibacterial and antibiofilm activity against MDR A. baumannii isolates.}, }
@article {pmid39297751, year = {2024}, author = {Erfaninejad, M and Mahmoudabadi, AZ and Hashemzadeh, M and Maraghi, E and Fatahinia, M}, title = {Characteristics of Candida albicans Derived From HIV-Positive Individuals With Oral Candidiasis: Genotyping, Phenotypic Variation, Antifungal Susceptibility, and Biofilm Formation.}, journal = {Journal of clinical laboratory analysis}, volume = {38}, number = {19-20}, pages = {e25103}, pmid = {39297751}, issn = {1098-2825}, support = {OG-9945//Ahvaz Jundishapur University of Medical Sciences/ ; }, mesh = {Humans ; *Biofilms/drug effects/growth &amp; development ; *Candida albicans/genetics/drug effects ; *Candidiasis, Oral/microbiology ; *Antifungal Agents/pharmacology ; *Microbial Sensitivity Tests ; *Genotype ; *Phenotype ; HIV Infections/complications ; Male ; Female ; Adult ; Drug Resistance, Fungal/genetics ; }, abstract = {BACKGROUND: Oral candidiasis (OC) is one of the most common mucosal infections in those afflicted with HIV/AIDS. This study aimed to provide detailed information on the phenotype, genotype, antifungal susceptibility, and biofilm formation ability of oral Candida albicans isolated from HIV-infected patients with OC.<br><br>METHODS: A total of 25 C. albicans isolates were collected from oral lesions of HIV-infected patients referred to Behavioral Diseases Counseling Center affiliated with Ahvaz Jundishapur University of Medical Sciences, Iran. The antifungal susceptibility testing was done according to CLSI M27 guideline (fourth edition). The crystal violet method was used to evaluate the biofilm formation ability of isolates. Different phenotypes were identified on yeast extract-peptone-dextrose agar medium supplemented with phloxine B. Genotyping analysis of the isolates was performed using high-resolution melting (HRM) assays and ABC genotyping.<br><br>RESULTS: The highest and lowest susceptibility of the C. albicans isolates was found for fluconazole 24 (96%) and ITC 18 (72%), respectively. Forty-eight percent of the isolates had high biofilm formation ability and exhibited gray cell type. The most common genotype was genotype B (52%). HRM analysis of HIS3, EF3, and CDC3 markers showed three, four, and five different groups, respectively.<br><br>CONCLUSION: Investigating the phenotype, antifungal susceptibility and biofilm formation ability of the C. albicans isolates obtained from oral lesions of HIV-infected patients revealed that the dominant genotypes in the current research could cause more serious infections from the oral source. We recommend further research with a larger sample size to determine the molecular epidemiology of C. albicans among HIV patients in Iran.}, }
@article {pmid39297664, year = {2024}, author = {Ji, X and Fan, D and Wang, J and Zhang, B and Hu, Y and Lv, H and Wu, J and Sun, Y and Liu, J and Zhang, Y and Wang, S}, title = {Cronobacter sakazakii lysozyme inhibitor LprI mediated by HmsP and c-di-GMP is essential for biofilm formation and virulence.}, journal = {Applied and environmental microbiology}, volume = {90}, number = {10}, pages = {e0156424}, pmid = {39297664}, issn = {1098-5336}, mesh = {*Biofilms/growth &amp; development/drug effects ; *Cronobacter sakazakii/genetics/physiology/drug effects/pathogenicity ; Virulence ; *Bacterial Proteins/genetics/metabolism ; Animals ; Rats ; *Cyclic GMP/analogs &amp; derivatives/metabolism ; *Muramidase ; Enterobacteriaceae Infections/microbiology ; Humans ; }, abstract = {Cronobacter sakazakii poses a significant threat, particularly to neonates and infants. Despite its strong pathogenicity, understanding of C. sakazakii biofilms and their role in infections remains limited. This study investigates the roles of HmsP and c-di-GMP in biofilm formation and identifies key genetic and proteomic elements involved. Gene knockout experiments reveal that HmsP and c-di-GMP are linked to biofilm formation in C. sakazakii. Comparative proteomic profiling identifies the lysozyme inhibitor protein LprI, which is downregulated in hmsP knockouts and upregulated in c-di-GMP knockouts, as a potential biofilm formation factor. Further investigation of the lprI knockout strain shows significantly reduced biofilm formation and decreased virulence in a rat infection model. Additionally, LprI is demonstrated to bind extracellular DNA, suggesting a role in anchoring C. sakazakii within the biofilm matrix. These findings enhance our understanding of the molecular mechanisms underlying biofilm formation and virulence in C. sakazakii, offering potential targets for therapeutic intervention and food production settings.IMPORTANCECronobacter sakazakii is a bacterium that poses a severe threat to neonates and infants. This research elucidates the role of the lysozyme inhibitor LprI, modulated by HmsP and c-di-GMP, and uncovers a key factor in biofilm formation and virulence. The findings offer crucial insights into the molecular interactions that enable C. sakazakii to form resilient biofilms and persist in hostile environments, such as those found in food production facilities. These insights not only enhance our understanding of C. sakazakii pathogenesis but also identify potential targets for novel therapeutic interventions to prevent or mitigate infections. This work is particularly relevant to public health and the food industry, where controlling C. sakazakii contamination in powdered infant formula is vital for safeguarding vulnerable populations.}, }
@article {pmid39297645, year = {2024}, author = {Louvet, M and Li, J and Brandalise, D and Bachmann, D and Sala de Oyanguren, F and Labes, D and Jacquier, N and Genoud, C and Mucciolo, A and Coste, AT and Sanglard, D and Lamoth, F}, title = {Ume6-dependent pathways of morphogenesis and biofilm formation in Candida auris.}, journal = {Microbiology spectrum}, volume = {12}, number = {11}, pages = {e0153124}, pmid = {39297645}, issn = {2165-0497}, support = {310030_192611//Swiss National Science Foundation (SNSF)/ ; //Fondation Santos-Suarez pour la Recherche M&#xe9;dicale (Santos-Suarez Foundation for Medical Research)/ ; //Carigest (Carigest SA)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Fungal Proteins/genetics/metabolism ; *Candida auris/genetics/metabolism/growth &amp; development ; *Morphogenesis ; *Gene Expression Regulation, Fungal ; *Transcription Factors/genetics/metabolism ; Humans ; Virulence/genetics ; Candidiasis/microbiology ; }, abstract = {Candida auris is a yeast pathogen causing nosocomial outbreaks of candidemia. Its ability to adhere to inert surfaces and to be transmitted from one patient to another via medical devices is of particular concern. Like other Candida spp., C. auris has the ability to transition from the yeast form to pseudohyphae and to build biofilms. Moreover, some isolates have a unique capacity to form aggregates. These morphogenetic changes may impact virulence. In this study, we demonstrated the role of the transcription factor Ume6 in C. auris morphogenesis. Genetic hyperactivation of Ume6 induced filamentation and aggregation. The Ume6-hyperactivated strain (UME6[HA]) also exhibited increased adhesion to inert surface and formed biofilms of higher biomass compared to the parental strain. Transcriptomic analyses of UME6[HA] revealed enrichment of genes encoding for adhesins, proteins involved in cell wall organization, sterol biosynthesis, and aspartic protease activities. The three most upregulated genes compared to wild-type were those encoding for the agglutin-like sequence adhesin Als4498, the C. auris-specific adhesin Scf1, and the hypha-specific G1 cyclin-related protein Hgc1. The deletion of these genes in the UME6[HA] background showed that Ume6 controls filamentation via Hgc1 and aggregation via Als4498 and Scf1. Adhesion to inert surface was essentially triggered by Scf1. However, Als4498 and Hgc1 were also crucial for biofilm formation. Our data show that Ume6 is a universal regulator of C. auris morphogenesis via distinct modulators.IMPORTANCEC. auris represents a public health threat because of its ability to cause difficult-to-treat infections and hospital outbreaks. The morphogenetic plasticity of C. auris, including its ability to filament, to form aggregates or biofilms on inert surfaces, is important to the fungus for interhuman transmission, skin or catheter colonization, tissue invasion, antifungal resistance, and escape of the host immune system. This work deciphered the importance of Ume6 in the control of distinct pathways involved in filamentation, aggregation, adhesion, and biofilm formation of C. auris. A better understanding of the mechanisms of C. auris morphogenesis may help identify novel antifungal targets.}, }
@article {pmid39305253, year = {2024}, author = {Lalitha, MM and Banerjee, S and Jayaraj, A and Kamath, A and Divakaran, D and Yadav, V and Lakavathu, M and Sajimon, J and Anil, P and Shaijumon, MM and Singh, NS and Kurapati, R}, title = {Two-Dimensional Materials/Biopolymer-Based Antimicrobial Coatings to Thwart Biofilm Formation on Medical Implants.}, journal = {ACS applied bio materials}, volume = {7}, number = {10}, pages = {6332-6342}, doi = {10.1021/acsabm.4c00725}, pmid = {39305253}, issn = {2576-6422}, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; *Escherichia coli/drug effects ; *Coated Materials, Biocompatible/chemistry/pharmacology ; *Prostheses and Implants ; *Bacillus subtilis/drug effects ; *Microbial Sensitivity Tests ; *Materials Testing ; Particle Size ; Surface Properties ; Chitosan/chemistry/pharmacology ; Humans ; Graphite/chemistry/pharmacology ; Phosphorus/chemistry ; }, abstract = {Infections associated with medical implants due to bacterial adhesion and biofilm formation are a serious problem, leading to acute health risks to patients by compromising their immune system. Therefore, suppressing biofilm formation on biomedical implants is a challenging task, especially for overcoming the drug resistance of bacterial biofilms. Herein, a synergistic efficient surface coating method was developed to inhibit biofilm formation on a model medical implant by combining the antimicrobial property of trimethyl chitosan (TMC) with either 2D material graphene oxide (GO) or black phosphorus (BP) sheets using layer-by-layer (LbL) self-assembly. The multilayer coatings of TMC/GO and TMC/BP were optimized on the glass surface (a model implant) and characterized by using spectroscopic and microscopy techniques. Next, we investigated the antibiofilm formation properties of the TMC/GO and TMC/BP coatings on glass surfaces against both Gram-negative, Escherichia coli (E. coli), and Gram-positive, Bacillus subtilis (B. subtilis), bacteria. The antibiofilm formation was studied using crystal violet (CV) and live/dead assays. Both the live/dead and the CV assays confirmed that the TMC/2D material (2DM)-coated surfaces prevented biofilm formation much more effectively compared to the uncoated surfaces. Scanning electron microscopy analyses revealed that the bacteria were affected physically by incubating with TMC/2DM-coated surfaces due to membrane perturbation, thereby preventing cell attachment and biofilm formation. Further, BP composite coatings (TMC/BP) showed a much better ability to thwart biofilm formation than GO composite coatings (TMC/GO). Also, multilayer coatings showed superior cytocompatibility with human foreskin fibroblast (HFF). Our results demonstrate that the developed coatings TMC/2DMs could be potential candidates for thwarting biofilm formation on medical implants.}, }
@article {pmid39304122, year = {2024}, author = {Nguyen, HK and Duke, MM and Grayton, QE and Broberg, CA and Schoenfisch, MH}, title = {Impact of nitric oxide donors on capsule, biofilm and resistance profiles of Klebsiella pneumoniae.}, journal = {International journal of antimicrobial agents}, volume = {64}, number = {5}, pages = {107339}, pmid = {39304122}, issn = {1872-7913}, support = {R01 DE032060/DE/NIDCR NIH HHS/United States ; R01 DK132778/DK/NIDDK NIH HHS/United States ; }, mesh = {*Klebsiella pneumoniae/drug effects ; *Biofilms/drug effects ; *Nitric Oxide Donors/pharmacology ; *Bacterial Capsules/drug effects ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; Nitric Oxide/metabolism ; Humans ; Drug Resistance, Bacterial ; }, abstract = {Klebsiella pneumoniae is considered to be a critical public health threat due to its ability to cause fatal, multi-drug-resistant infections in the bloodstream and key organs. The polysaccharide-based capsule layer that shields K. pneumoniae from clearance via innate immunity is a prominent virulence factor. K. pneumoniae also forms biofilms on biotic and abiotic surfaces. These biofilms significantly reduce penetration by, and antibacterial activity from, traditional antibiotics. Nitric oxide (NO), an endogenous molecule involved in the innate immune system, is equally effective at eradicating bacteria but without engendering resistance. This study investigated the effects of NO-releasing small molecules capable of diverse release kinetics on the capsule and biofilm formation characteristics of multiple K. pneumoniae strains. The use of NO donors with moderate and extended NO-release properties (i.e., half-life >1.8 h) inhibited bacterial growth. Additionally, treatment with NO decreased capsule mucoviscosity in K. pneumoniae strains that normally exhibit hypermucoviscosity. The NO donors were also effective against K. pneumoniae biofilms at the same minimum biocidal concentrations that eliminated planktonic bacteria, while meropenem showed little antibacterial action in the same experiments. These results represent the first account of exogenous NO affecting biomarkers involved in K. pneumoniae infections, and may therefore inform future development of NO-based therapeutics for treating such infections.}, }
@article {pmid39303497, year = {2025}, author = {Lou, X and Wu, Y and Chen, Z and Zhang, Q and Xiao, X and Fang, Z}, title = {Novel insights into biofilm formation and the key differentially expressed genes in Yersinia enterocolitica from meat: Implications for food safety and disease prevention.}, journal = {International journal of food microbiology}, volume = {426}, number = {}, pages = {110914}, doi = {10.1016/j.ijfoodmicro.2024.110914}, pmid = {39303497}, issn = {1879-3460}, mesh = {*Biofilms/growth &amp; development ; *Yersinia enterocolitica/genetics ; Animals ; *Food Safety ; *Yersinia Infections/microbiology ; Meat/microbiology ; Food Microbiology ; Gene Expression Regulation, Bacterial ; Ducks/microbiology ; Poultry/microbiology ; Humans ; Bacterial Proteins/genetics/metabolism ; }, abstract = {Yersinia enterocolitica is an important foodborne pathogen that can cause a zoonotic disease known as yersiniosis, which causes symptoms such as acute diarrhea, mesenteric adenitis, terminal ileum inflammation, pseudo appendicitis, sepsis, and other complications. The mechanism of biofilm formation in Y. enterocolitica remains poorly understood, with limited research available on this topic. This study systematically examined the distribution characteristics and biofilm formation ability of Y. enterocolitica isolated from poultry and livestock related samples. Analysis of food samples collected indicated significant presence of Y. enterocolitica (207/670, 30.9 %), particularly in frozen duck meat (7/11, 63.6 %). Majority of the isolated strains did not demonstrate biofilm-forming ability (52.7 %), while a notable percentage exhibited moderate (6.8 %) to strong (11.6 %) biofilm-forming ability. Additionally, a significant percentage of strains (16/207, 7.7 %) displayed extremely high optical density/cut-off OD (OD/ODC) ratios (the average OD value of each sample divided by the average OD value of the negative controls of each 96-well plate plus 3 standard deviations) (exceeding 10). Time-course analysis of biofilm formation in 10 isolates revealed three distinct patterns: (i) rapid increase from 6 h to 12 h, with gradual peak between 48 and 72 h followed by a slight decline and stabilization; (ii) little biofilm formation at 24 h with a gradual increase up to 96 h, maintaining this level until 120 h; and (iii) complete absence of biofilm formation throughout the experiment. Subsequent examination of differentially expressed genes (DEGs) in planktonic cells and biofilms of two strains with distinct biofilm formation capabilities identified seven metabolic pathways, including ribosome, photosynthesis, fatty acid degradation, valine, leucine, and isoleucine degradation, as well as pinene, camphor, and geraniol degradation. Significantly elevated expression levels of genes associated with flagellar assembly, bacterial chemotaxis, and quorum sensing (partially) were observed exclusively in planktonic cells of the selected strain with stronger biofilm-forming ability, implying that the heightened expression of flagellar assembly and bacterial chemotaxis-related genes is an important but not sole determinant of biofilm formation. The study contributes to the elucidation of the underlying mechanisms governing biofilm formation in Y. enterocolitica and may offer valuable insights for the advancement of novel food safety strategies.}, }
@article {pmid39300677, year = {2024}, author = {Murshid, RM and Al-Ouqaili, MTS and Kanaan, BAJ}, title = {Microbial Vaginosis and its Relation to Single or Multi-Species Biofilm in Iraqi Women: Clinical and Microbiological Study.}, journal = {Pakistan journal of biological sciences : PJBS}, volume = {27}, number = {8}, pages = {404-412}, doi = {10.3923/pjbs.2024.404.412}, pmid = {39300677}, issn = {1812-5735}, mesh = {Humans ; Female ; *Vaginosis, Bacterial/microbiology/diagnosis ; *Biofilms/growth &amp; development ; Iraq ; Adult ; Vagina/microbiology ; Young Adult ; Microbial Sensitivity Tests ; Candida albicans/isolation &amp; purification ; Candidiasis, Vulvovaginal/microbiology/diagnosis ; Middle Aged ; }, abstract = {Background and Objective: Bacterial vaginosis (BV) is the primary aetiology of vaginal discharge causing significant public health consequences. The study aims to detect the frequency of bacterial vaginosis and to assess the effectiveness of the Amsel's criteria and Nugent's score system as diagnostic tests for BV. Materials and Methods: A total of 135 high vaginal swab samples were obtained and analyzed microbiologically to detect the presence of Amsel clinical criteria and to determine the Nugent's score using gram staining. The microbiological culture, antimicrobial susceptibility test and bacterial biofilm generation were conducted using standardized laboratory conditions. The study data were analyzed using SPSS version 16.0 and Microsoft Excel. The Chi-square test was used to ascertain any significant differences with a p-value of less than 0.05. Results: Out of 135 HVS, 60 (44.4 %) specimens revealed bacterial vaginosis and 30 (22.2%) represent Candida albicans vaginitis. In comparing Amsel's criteria with Nugent's score, the sensitivity, specificity, positive and negative predictive values were 94.7, 92.3, 90 and 96%, respectively. Also, 26 (50%) of the study isolates were produced biofilm strongly. Further, Gardnerella vaginalis was the study isolate that produced biofilm strongly (66.6%) followed by Pseudomonas aeruginosa (57.1%). Conclusion: The study highlights the significance of Amsel's clinical criteria and the Nugent's score system as diagnostic tests for bacterial vaginosis in outpatient settings. Additionally, there is an association between recurrent bacterial vaginosis and vulvovaginal candidiasis. Moreover, addressing vaginal disorders caused by single-species or multi-species biofilms create the researcher to be focused on studying multi-species biofilms.}, }
@article {pmid39297992, year = {2024}, author = {Gao, S and Yuan, S and Quan, Y and Jin, W and Shen, Y and Liu, B and Wang, Y and Wang, Y}, title = {Effects of AI-2 quorum sensing related luxS gene on Streptococcus suis formatting monosaccharide metabolism-dependent biofilm.}, journal = {Archives of microbiology}, volume = {206}, number = {10}, pages = {407}, pmid = {39297992}, issn = {1432-072X}, support = {32172852//National Natural Science Foundation of China/ ; 222300420005//Excellent Youth Foundation of Henan Scientific Committee/ ; 24IRTSTHN033//Program for Innovative Research Team (in Science and Technology) in University of Henan Province/ ; }, mesh = {*Biofilms/growth &amp; development ; *Carbon-Sulfur Lyases/genetics/metabolism ; *Bacterial Proteins/genetics/metabolism ; *Streptococcus suis/genetics/metabolism/growth &amp; development ; *Quorum Sensing/genetics ; *Monosaccharides/metabolism ; Animals ; Gene Expression Regulation, Bacterial ; Gene Deletion ; Virulence/genetics ; Lactones/metabolism ; Larva/microbiology ; Homoserine/analogs &amp; derivatives/metabolism ; }, abstract = {Biofilm is the primary cause of persistent infections caused by Streptococcus suis (S. suis). Metabolism and AI-2 quorum sensing are intricately linked to S. suis biofilm formation. Although the role of the AI-2 quorum sensing luxS gene in S. suis biofilm has been reported, its specific regulatory mechanism remains unclear. This study explored the differences in biofilm formation and monosaccharide metabolism among the wild type (WT), luxS mutant (ΔluxS) and complement strain (CΔluxS), and Galleria mellonella larvae were used to access the effect of luxS gene deletion on the virulence of S. suis in different monosaccharide medias. The results indicated that deletion of the luxS gene further compromised the monosaccharide metabolism of S. suis, impacting its growth in media with fructose, galactose, rhamnose, and mannose as the sole carbon sources. However, no significant impact was observed in media with glucose and N-acetylglucosamine. This deletion also weakened EPS synthesis, thereby diminishing the biofilm formation capacity of S. suis. Additionally, the downregulation of adhesion gene expression due to luxS gene deletion was found to be independent of the monosaccharide medias of S. suis.}, }
@article {pmid39302957, year = {2024}, author = {Ramos, RCPDS and de Oliveira, NS and Bianchini, LF and Azevedo-Alanis, LR and Pimentel, IC and Hardy, AMTG and Murata, RM and Glassey, J and Rosa, EAR}, title = {Cunninghamella echinulata DSM1905 biofilm-based L-asparaginase production in pneumatically-driven bioreactors.}, journal = {PloS one}, volume = {19}, number = {9}, pages = {e0308847}, pmid = {39302957}, issn = {1932-6203}, mesh = {*Bioreactors/microbiology ; *Cunninghamella/metabolism ; *Biofilms/growth &amp; development ; *Asparaginase/biosynthesis/metabolism ; Fermentation ; Biomass ; }, abstract = {We evaluated by comparing the performance of three pneumatically-driven bioreactors in the production of L-asparaginase (L-ASNase), an enzyme used to treat leukaemia and lymphoma. A two-step screening process was conducted to detect Cunninghamella spp. strains producing L-ASNase. Cunninghamella echinulata DSM1905 produced the highest levels of L-ASNase during screening assays. Subsequently, fermentations were performed in bubble column (BCR), airlift (ALR), and hybrid fixed-bed airlift (FB-ALR) bioreactors to determine the best upstream bioprocess. Mycelial biomass production was higher in BCR than in ALR and FB-ALR (p ≤ 0.0322). The activity of L-ASNase produced in FB-ALR, in which the fungus grew as a consistent biofilm, was significantly higher (p ≤ 0.022) than that from ALR, which was higher than that of BCR (p = 0.036). The specific activity of ALR and FB-ALR presented no differences (p = 0.073), but it was higher than that of BCR (p ≤ 0.032). In conclusion, C. echinulata DSM1905, grown under the biofilm phenotype, produced the highest levels of L-ASNase, and FB-ALR was the best upstream system for enzyme production.}, }
@article {pmid39300947, year = {2025}, author = {Zeb, BS and Mahmood, Q and Irshad, M and Zafar, H and Wang, R}, title = {Sustainable treatment of combined industrial wastewater: synergistic phytoremediation with Eichhornia crassipes, Pistia stratiotes, and Arundo donax in biofilm wetlands.}, journal = {International journal of phytoremediation}, volume = {27}, number = {1}, pages = {128-134}, doi = {10.1080/15226514.2024.2403037}, pmid = {39300947}, issn = {1549-7879}, mesh = {*Biodegradation, Environmental ; *Wetlands ; *Eichhornia/metabolism ; *Wastewater ; *Biofilms ; *Water Pollutants, Chemical/metabolism ; *Waste Disposal, Fluid/methods ; *Araceae/metabolism ; *Industrial Waste ; }, abstract = {This study investigates the treatment of combined wastewater from Hattar Industrial Estate using Biofilm Wetlands (BW) planted with monoculture species: Eichhornia crassipes (EAC), Pistia stratiotes (WL), and Arundo donax (GR). Each species showed distinct capabilities in organic degradation, metal uptake, and pH stabilization. BW2, planted with EAC, achieved the highest total solids (TS) and total suspended solids (TSS) removal efficiencies of 66% and 65%, respectively. GR effectively reduced initial COD concentrations from 232 mg/L to 58.67 mg/L, while EAC and WL reached reductions to 72.78 mg/L and 70.67 mg/L, respectively. Overall, the plant efficiency ranking was EAC > GR > WL. These findings underscore the potential of these plant species in synergistic BW systems, highlighting their role as natural solutions for remediating complex industrial effluents. This research contributes to advancing eco-friendly wastewater treatment approaches, suggesting promising applications for sustainable practices in industrial contexts. RESEARCH HIGHLIGHTSThis research assessed the effectiveness of phytoremediation using Eichhornia crassipes, Pistia stratiotes, and Arundo donax for removing pollutants i.e. heavy metals (Cd, Pb, Ni, K, Ca, Mg, Na, Fe, Hg) nitrates, phosphates and sulfates from combined industrial wastewater of Hattar Industrial Estate Pakistan.It highlighted the potential of selected plant species' as natural treatment systems, providing crucial insights into their efficiency.Findings contribute to understanding nature-based solutions for complex industrial effluents.}, }
@article {pmid39299622, year = {2024}, author = {Ma, H and Wang, T and Li, G and Liang, J and Zhang, J and Liu, Y and Zhong, W and Li, P}, title = {A photo-modulated nitric oxide delivering hydrogel for the accelerated healing of biofilm infected chronic wounds.}, journal = {Acta biomaterialia}, volume = {188}, number = {}, pages = {169-183}, doi = {10.1016/j.actbio.2024.09.017}, pmid = {39299622}, issn = {1878-7568}, mesh = {Animals ; *Biofilms/drug effects ; *Wound Healing/drug effects ; *Hydrogels/chemistry/pharmacology ; Mice ; *Nitric Oxide/pharmacology/metabolism ; Methicillin-Resistant Staphylococcus aureus/drug effects ; Male ; Wound Infection/drug therapy/pathology/therapy/microbiology ; Staphylococcal Infections/drug therapy/therapy/pathology ; Chronic Disease ; }, abstract = {Biofilm infection and impaired healing of chronic wounds are posing tremendous challenges in clinical practice. In this study, we presented a versatile antimicrobial hydrogel capable of delivering nitric oxide (NO) in a controllable manner to dissipate biofilms, eliminate microorganisms, and promote the healing of chronic wounds. This hydrogel was constructed by Schiff-base crosslinking of oxidized dextran and antimicrobial peptide ε-poly-lysine, further encapsulating photothermal nanoparticles bearing NO donor. This hydrogel could continuously and slowly release NO, effectively dissipating biofilms, and promoting the proliferation of mouse fibroblasts and the migration of endothelial cells. Upon exposure to NIR laser irradiation, the hydrogel generated hyperthermia and rapidly released NO, resulting in the efficient elimination of a broad spectrum of drug-resistant Gram-positive/negative bacterial and fungal biofilms through the synergistic effects of NO, photothermal therapy, and the antibacterial peptide. Notably, the hydrogel demonstrated exceptional in vivo therapeutic outcomes in accelerating the healing process of mice diabetic wounds infected with methicillin-resistant Staphylococcus aureus by successfully eliminating biofilm infection, regulating inflammation, and facilitating angiogenesis and collagen deposition. Overall, this proposed hydrogel shows great promise in accommodating the various demands of the complex repair process of chronic wounds infected with biofilms. STATEMENT OF SIGNIFICANCE: The presence of biofilm infections and underlying dysfunctions in the healing process made chronic wound become stuck in the inflammation stage and difficult to heal. This work developed a NIR laser-modulated three-stage NO-releasing versatile antimicrobial hydrogel (DEPN) exhibiting good therapeutic efficacy for chronic wound. This DEPN hydrogel could inherently and slowly released NO to disperse biofilm. Upon NIR laser irradiation, the DEPN hydrogel generated hyperthermia and induced a rapid burst release of NO effectively eliminating a broad spectrum of drug-resistant bacterial and fungal biofilms. Subsequently, the DEPN hydrogel continually release NO slowly to promote the tissue remolding. This DEPN hydrogel displays great potential in treatment of chronic wounds infected with biofilm.}, }
@article {pmid39299599, year = {2024}, author = {da Silva, AM and Murillo, DM and Anbumani, S and von Zuben, AA and Cavalli, A and Obata, HT and Fischer, ER and de Souza E Silva, M and Bakkers, E and Souza, AA and Carvalho, HF and Cotta, MA}, title = {N-acetylcysteine effects on extracellular polymeric substances of Xylella fastidiosa: A spatiotemporal investigation with implications for biofilm disruption.}, journal = {International journal of antimicrobial agents}, volume = {64}, number = {5}, pages = {107340}, doi = {10.1016/j.ijantimicag.2024.107340}, pmid = {39299599}, issn = {1872-7913}, mesh = {*Biofilms/drug effects ; *Xylella/drug effects/physiology ; *Acetylcysteine/pharmacology ; *Extracellular Polymeric Substance Matrix/drug effects/metabolism ; Bacterial Adhesion/drug effects ; Anti-Bacterial Agents/pharmacology ; Spatio-Temporal Analysis ; }, abstract = {BACKGROUND: The matrix of extracellular polymeric substances (EPS) present in biofilms greatly amplifies the problem of bacterial infections, protecting bacteria against antimicrobial treatments and eventually leading to bacterial resistance. The need for alternative treatments that destroy the EPS matrix becomes evident. N-acetylcysteine (NAC) is one option that presents diverse effects against bacteria; however, the different mechanisms of action of NAC in biofilms have yet to be elucidated.<br><br>OBJECTIVES: In this work, we performed microscopy studies at micro and nano scales to address the effects of NAC at single cell level and early-stage biofilms of the Xylella fastidiosa phytopathogen.<br><br>METHODS: We show the physical effects of NAC on the adhesion surface and the different types of EPS, as well as the mechanical response of individual bacteria to NAC concentrations between 2 and 20 mg/mL.<br><br>RESULTS: NAC modified the conditioning film on the substrate, broke down the soluble EPS, resulting in the release of adherent bacteria, decreased the volume of loosely bound EPS, and disrupted the biofilm matrix. Tightly bound EPS suffered structural alterations despite no solid evidence of its removal. In addition, bacterial force measurements upon NAC action performed with InP nanowire arrays showed an enhanced momentum transfer to the nanowires due to increased cell mobility resulting from EPS removal.<br><br>CONCLUSIONS: Our results clearly show that conditioning film and soluble EPS play a key role in cell adhesion control and that NAC alters EPS structure, providing solid evidence that NAC actuates mainly on EPS removal, both at single cell and biofilm levels.}, }
@article {pmid39299433, year = {2024}, author = {Yao, H and Fan, Y and Emre, EST and Li, N and Ge, M and Wang, J and Wei, J}, title = {Alginate-modified ZnO anti-planktonic and anti-biofilm nanoparticles for infected wound healing.}, journal = {International journal of biological macromolecules}, volume = {}, number = {}, pages = {135739}, doi = {10.1016/j.ijbiomac.2024.135739}, pmid = {39299433}, issn = {1879-0003}, abstract = {Bacterial infections is one of the main factors delaying the wound healing, which has become a serious challenge for healthcare systems. Zinc oxide nanoparticles (ZnO NPs), which show broad-spectrum and excellent antibacterial activity, tend to aggregate easily and therefore hardly penetrate into bacterial biofilms, showing limited anti-biofilm properties. Herein，alginate (ALG) modified ZnO NPs (ZnO@ALG) were prepared via the combination of mussel-inspired method and "thiol-Michael" click reaction, which showed excellent dispersion and biocompatibility. Besides, the interactions between ZnO@ALG and bacteria was much better than that of ZnO NPs, and makes the bacteria produced more reactive oxygen species (ROS) than bare ZnO NPs. The anti-planktonic activity of ZnO@ALG (250 μg/mL) could reach almost 100 %, which was 2-3 times higher than that of bare ZnO NPs. In addition, the ZnO@ALG could significantly accelerate the healing of S. aureus infected wounds, and the wound healing rate of ZnO@ALG group was about 79.2 %, which was significantly higher than that of ZnO NPs (~65.8 %). This study demonstrates that the ZnO@ALG holds a great potential in the anti-planktonic and anti-biofilm fields, and the ALG-modification method can be an effective strategy to enhance the antibacterial properties of nanomaterials.}, }
@article {pmid39299341, year = {2024}, author = {Liu, J and Hu, M and Hu, M and Wang, J and Zhang, T and Wang, Y and Wang, X}, title = {Responses of suspended sludge and biofilm in a SNAD system under C/N elevation: Microbial activity, nitrogen conversion flux and molecular ecological network.}, journal = {The Science of the total environment}, volume = {954}, number = {}, pages = {176236}, doi = {10.1016/j.scitotenv.2024.176236}, pmid = {39299341}, issn = {1879-1026}, mesh = {*Biofilms ; *Waste Disposal, Fluid/methods ; *Denitrification ; *Sewage/microbiology ; *Nitrogen/analysis ; Nitrification ; Wastewater/microbiology ; Carbon/metabolism ; Bacteria/metabolism ; }, abstract = {The simultaneous partial nitrification, anammox and denitrification (SNAD) process had received widespread attention as an advanced wastewater treatment process. In this study, the SNAD mainstream nitrogen removal process with the incorporation of polyurethane sponge packing under different C/N conditions was investigated. Results showed that the highest nitrogen removal efficiency of the system was achieved at the C/N of 2.0, while the high C/N (3.5) significantly deteriorate the nitrogen removal efficiency. Meanwhile, high C/N (3.5) significantly inhibited the activity and abundance of anammox bacteria (mainly Candidatus_Kuenenia), resulting in the decreased contribution of anammox (from 63.14 % to 48.09 %). The significant divergence of microbial interactions in the suspended sludge and biofilm was observed with increasing C/N. Compared with suspended sludge, biofilm facilitated higher abundance and activity of anammox bacteria, and the molecular ecological network of biofilm displayed better stability and more efficient mass transfer efficiency between microorganisms. The C/N of 3.5 simplified the subnetworks of Chloroflexi and Proteobacteria but increased the positive interactions between Planctomycetota and other microbes. Anammox bacteria were found as keystone species only in biofilm system. This study provided a theoretical basis and technical guidance for the application of SNAD process in municipal wastewater treatment.}, }
@article {pmid39299138, year = {2024}, author = {Ren, WT and He, ZL and Lv, Y and Wang, HZ and Deng, L and Ye, SS and Du, JS and Wu, QL and Guo, WQ}, title = {Carbon chain elongation characterizations of electrode-biofilm microbes in electro-fermentation.}, journal = {Water research}, volume = {267}, number = {}, pages = {122417}, doi = {10.1016/j.watres.2024.122417}, pmid = {39299138}, issn = {1879-2448}, mesh = {*Biofilms ; *Electrodes ; *Bioreactors/microbiology ; Fermentation ; Fatty Acids/metabolism ; Bacteria/metabolism ; Carbon ; Sewage/microbiology ; }, abstract = {The higher efficiency of electro-fermentation in synthesizing medium-chain fatty acids (MCFAs) compared to traditional fermentation has been acknowledged. However, the functional mechanisms of electrode-biofilm enhancing MCFAs synthesis remain research gaps. To address this, this study proposed a continuous flow electrode-biofilm reactor for chain elongation (CE). After 225 days of operation, stable electrode-biofilms formed and notably improved caproate yield by more than 38 %. The electrode-biofilm was enriched with more CE microorganisms and electroactive bacteria compared to the suspended sludge microorganisms, including Caproicibacterium, Oscillibacter and Pseudoramibacter. Besides, the upregulated CE pathways were evaluated by metagenomic analysis, and the results indicated that the pathways such as acetyl-CoA and malonyl-[acp] formation, reverse beta-oxidation, and fatty acid biosynthesis pathway were all markedly enhanced in cathodic biofilm, more than anodic biofilm and suspended microorganisms. Moreover, microbial community regulated processes like bacterial chemotaxis, flagellar assembly and quorum sensing, crucial for electrode-biofilm formation. Electron transfer, energy metabolism, and microbial interactions were found to be prominently upregulated in the cathodic biofilm, surpassing levels observed in anodic biofilm and suspended sludge microorganisms, which further enhanced CE efficiency. In addition, the statistical analyses further highlighted key microbial functions and interactions within the cathodic biofilm. Oscillospiraceae_bacterium was identified to be the most active microbe, alongside pivotal roles played by Caproiciproducens_sp._NJN-50, Clostridiales_bacterium, Prevotella_sp. and Pseudoclavibacter_caeni. Eventually, the proposed microbial collaboration mechanisms of cathodic biofilm were ascertained. Overall, this study uncovered the biological effects of the electrode-biofilm on MCFAs electrosynthesis, thereby advancing biochemicals production and filling the knowledge gaps in CE electroactive biofilm reactors.}, }
@article {pmid39298451, year = {2024}, author = {Wahab, AT and Nadeem, F and Salar, U and Bilal, HM and Farooqui, M and Javaid, S and Sadaf, S and Khan, KM and Choudhary, MI}, title = {Coumarin derivatives as new anti-biofilm agents against Staphylococcus aureus.}, journal = {PloS one}, volume = {19}, number = {9}, pages = {e0307439}, pmid = {39298451}, issn = {1932-6203}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Coumarins/pharmacology/chemistry ; *Staphylococcus aureus/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Microbial Sensitivity Tests ; Humans ; Microscopy, Atomic Force ; }, abstract = {Staphylococcus aureus infections are the primary causes of morbidity, and mortality, particularly in immuno-compromised individuals. S. aureus associated infections are acquired from community, as well as hospital settings, and difficult to treat because of the emerging resistance against available antibiotics. One of the key factors of its resistance is the biofilm formation, which can be targeted to treat S. aureus-induced infections. Currently, there is no drug available that function by targeting the biofilm. This unmet need demands the discovery of drug candidates against S. aureus biofilm. The present study was designed to evaluate coumarin derivatives 1-21 against S. aureus biofilm. The 96-well plate crystal violet assay was employed for the quantification of biofilm. Results showed that the coumarin derivatives 2-4, 10, and 17 possess potent antibiofilm activity, with MBIC values between 25-100 μg/mL. The results were further confirmed through atomic force microscopy (AFM), scanning electron (SEM), and fluorescence microscopic studies. The quantitative RT-PCR analysis revealed the downregulation of biofilm associated genes, icaA and icaD. These coumarin derivatives were also found to be non-cytotoxic to fibroblasts. This study, therefore, identifies the antibiofilm potential of coumarin derivatives that will pave the way for further research on these derivatives.}, }
@article {pmid39296039, year = {2024}, author = {Wang, J and Hu, Y and Xue, Y and Wang, K and Mao, D and Pan, XY and Rui, Y}, title = {PMMA-induced biofilm promotes Schwann cells migration and proliferation mediated by EGF/Tnc/FN1 to improve sciatic nerve defect.}, journal = {Heliyon}, volume = {10}, number = {17}, pages = {e37231}, pmid = {39296039}, issn = {2405-8440}, abstract = {OBJECTIVE: The purpose of this study is to investigate the role of PMMA-induced biofilm in nerve regeneration compared with silicone-induced biofilm involved in the mechanism.<br><br>METHODS: PMMA or silicon rods were placed next to the sciatic nerve to induce a biological membrane which was assayed by PCR, Western blot, immunohistochemistry, immunofluorescence and proteomics. A 10&#xa0;mm sciatic nerve gaps were repaired with the autologous nerve wrapped in an induced biological membrane. The repair effects were observed through general observation, functional evaluation of nerve regeneration, ultrasound examination, neural electrophysiology, the wet weight ratio of bilateral pretibial muscle and histological evaluation. Cell proliferation and migration of Schwann cells co-cultured with EGF-treated fibroblasts combined with siRNA were investigated.<br><br>RESULTS: The results indicated that expression of GDNF, NGF and VEGF along with neovascularization was similar in the silicone and PMMA group and as the highest at 6 weeks after operation. Nerve injury repair mediated by toluidine blue and S100&#x3b2;/NF200 expression, the sensory and motor function evaluation, ultrasound, target organ muscle wet-weight ratio, percentage of collagen fiber, electromyography and histochemical staining were not different between the two groups and better than blank group. EGF-treated fibroblasts promoted proliferation and migration may be Tnc expression dependently.<br><br>CONCLUSION: Our study suggested that PMMA similar to silicon induced biofilm may promote autogenous nerve transplantation to repair nerve defects through EGF/Tnc/FN1 to increase Schwann cells proliferation and migration.}, }
@article {pmid39295916, year = {2024}, author = {Hird, C and Jékely, G and Williams, EA}, title = {Microalgal biofilm induces larval settlement in the model marine worm Platynereis dumerilii.}, journal = {Royal Society open science}, volume = {11}, number = {9}, pages = {240274}, pmid = {39295916}, issn = {2054-5703}, abstract = {A free-swimming larval stage features in many marine invertebrate life cycles. To transition to a seafloor-dwelling juvenile stage, larvae need to settle out of the plankton, guided by specific environmental cues that lead them to an ideal habitat for their future life on the seafloor. Although the marine annelid Platynereis dumerilii has been cultured in research laboratories since the 1950s and has a free-swimming larval stage, specific environmental cues that induce settlement in this nereid worm are yet to be identified. Here, we demonstrate that microalgal biofilm is a key settlement cue for P. dumerilii larvae, inducing earlier onset of settlement and enhancing subsequent juvenile growth as a primary food source. We tested the settlement response of P. dumerilii to 40 different strains of microalgae, predominantly diatom species, finding that P. dumerilii have species-specific preferences in their choice of settlement substrate. The most effective diatom species for inducing P. dumerilii larval settlement were benthic pennate species including Grammatophora marina, Achnanthes brevipes and Nitzschia ovalis. The identification of specific environmental cues for P. dumerilii settlement enables a link between its ecology and the sensory and nervous system signalling that regulates larval behaviour and development. Incorporation of diatoms into P. dumerilii culture practices will improve the husbandry of this marine invertebrate model.}, }
@article {pmid39294663, year = {2024}, author = {Cyris, M and Festerling, J and Kahl, M and Springer, C and Dörfer, CE and Graetz, C}, title = {Guided biofilm therapy versus conventional protocol-clinical outcomes in non-surgical periodontal therapy.}, journal = {BMC oral health}, volume = {24}, number = {1}, pages = {1105}, pmid = {39294663}, issn = {1472-6831}, mesh = {Humans ; *Biofilms ; Female ; Male ; Middle Aged ; Treatment Outcome ; *Dental Scaling/methods ; Adult ; *Periodontal Pocket/therapy ; *Periodontal Index ; Single-Blind Method ; Ultrasonic Therapy/methods ; Chronic Periodontitis/therapy/microbiology ; Follow-Up Studies ; Periodontal Debridement/methods ; Aged ; }, abstract = {BACKGROUND: The aim of the randomized controlled clinical trial study was to evaluate the effectiveness in reducing pathologically increased pocket probing depths (PPD > 3 mm) using the Guided Biofilm Therapy (GBT) protocol (adapted to the clinical conditions in non-surgical periodontal therapy (NSPT): staining, air-polishing, ultrasonic scaler, air-polishing) compared to conventional instrumentation (staining, hand curettes/sonic scaler, polishing with rotary instruments) both by less experienced practitioners (dental students).<br><br>METHODS: All patients were treated according to a split-mouth design under supervision as diseased teeth of quadrants I/III and II/IV randomly assigned to GBT or conventional treatment. In addition to the treatment time, periodontal parameters such as PPD and bleeding on probing (BOP) before NSPT (T0) and after NSPT (T1: 5&#x2009;&#xb1;&#x2009;2 months after T0) were documented by two calibrated and blinded examiners (Ethics vote/ Trial-register: Kiel-D509-18/ DRKS00026041).<br><br>RESULTS: Data of 60 patients were analyzed (stage III/IV: n&#x2009;=&#x2009;36/ n&#x2009;=&#x2009;24; grade A/ B/ C: n&#x2009;=&#x2009;1/ n&#x2009;=&#x2009;31/ n&#x2009;=&#x2009;28). At T1, a PPD reduction of all diseased tooth surfaces was observed in 57.0% of the GBT group and 58.7% of the control group (p&#x2009;=&#x2009;0.067). The target endpoint (PPD&#x2009;&#x2264;&#x2009;4 mm without BOP) was achieved in 11.5% for GBT (conventional treatment: 11.2%; p&#x2009;=&#x2009;0.714). With the exception for number of sites with BOP, which was at T1 15.9% in the GBT group and 14.3% in the control group (p&#x2009;<&#x2009;0.05) no significant differences between the outcomes of the study were found. At 30.3(28.3) min, the treatment time was significantly shorter in GBT than in the control group at 34.6(24.5) min (p&#x2009;<&#x2009;0.001).<br><br>CONCLUSIONS: With both protocols (GBT/ conventional instrumentation) comparably good clinical treatment results can be achieve in NSPT in stage III-IV periodontitis patients.<br><br>TRIAL REGISTRATION: The study was registered before the start of the study and can be found under the number DRKS00026041 in the German Clinical Trials Register. The registration date was 19/08/2021.}, }
@article {pmid39294648, year = {2024}, author = {Moradinezhad, M and Abbasi Montazeri, E and Hashemi Ashtiani, A and Pourlotfi, R and Rakhshan, V}, title = {Biofilm formation of Streptococcus mutans, Streptococcus sanguinis, Staphylococcus epidermidis, Staphylococcus aureus, Lactobacillus casei, and Candida Albicans on 5 thermoform and 3D printed orthodontic clear aligner and retainer materials at 3 time points: an in vitro study.}, journal = {BMC oral health}, volume = {24}, number = {1}, pages = {1107}, pmid = {39294648}, issn = {1472-6831}, mesh = {*Biofilms/growth &amp; development ; *Printing, Three-Dimensional ; *Streptococcus mutans ; *Staphylococcus epidermidis ; *Candida albicans/physiology ; *Staphylococcus aureus ; *Polyethylene Terephthalates ; *Streptococcus sanguis ; In Vitro Techniques ; *Lacticaseibacillus casei ; *Orthodontic Retainers/microbiology ; Polyethylene Glycols ; Humans ; Computer-Aided Design ; }, abstract = {INTRODUCTION: Orthodontic clear aligners and retainers have numerous advantages that is making them ever increasingly popular. However, they might, similar to any other oral appliance, contribute to biofilm formation and finally dental caries or white spot lesions or gingival inflammations. The literature on biofilm formation on orthodontic clear appliances is very scarce and limited to a few microorganisms and materials. Therefore, this experimental study evaluated the biofilm formation on 5 thermoformed and 3D printed CAD/CAM orthodontic retainers in 3 intervals.<br><br>METHODS: In this in vitro study, 345 specimens (270 test discs and 45 negative controls) were created from fabricated retainers. Retainers included a 3D printed CAD/CAM material (Detax) and four thermoformed retainers [Erkodent (polyethylene terephthalate glycol [PETG]); EasyVac (polyethylene); DB (polyester based on terephthalic acid); and Clear Tech]. They were all 1&#xa0;mm thick, and all completely fabricated, i.e., heated or printed. The discs were placed in 96-well plates. Microorganisms were cultured on 270 discs for 24&#xa0;h (90 discs), 72&#xa0;h (90 other discs), and 5 days or 120&#xa0;h (90 other discs). Biofilm formation of the strains and negative controls was measured using the microtiter plate assay by ELISA reading. The microbes' ability to produce biofilm was categorized based on the comparison of average optical density (OD) of tests versus a cut-off point OD (ODc) calculated as the average of the OD of corresponding negative controls plus 3&#xd7; its standard deviation: non-biofilm former [OD&#x2009;&#x2264;&#x2009;ODc], weak biofilm former [ODc&#x2009;<&#x2009;OD &#x2264; (2 &#xd7; ODc)], moderate biofilm former [(2 &#xd7; ODc)&#x2009;<&#x2009;OD &#x2264; (4 &#xd7; ODc)], and strong biofilm former [(4 &#xd7; ODc)&#x2009;<&#x2009;OD]. These were also converted to ranked scores between zero (no biofilm) and 3. The difference between ODs with control ODs were calculated. These were analyzed using 3-way ANOVA, 2-way ANOVA, and Tukey tests (&#x3b1;&#x2009;=&#x2009;0.05, &#x3b1;&#x2009;=&#x2009;0.008).<br><br>RESULTS: The 3-way ANOVA showed that the overall difference among the &#x394;ODs of 5 retainers (all microorganisms and all intervals combined, n&#x2009;=&#x2009;270) was not significant (F&#x2009;=&#x2009;1.860, P&#x2009;=&#x2009;0.119). Nevertheless, the difference among 3 intervals (F&#x2009;=&#x2009;31.607, P&#x2009;=&#x2009;0.0000) and the difference among the 6 microorganisms (F&#x2009;=&#x2009;24.044, P&#x2009;=&#x2009;0.0000) were significant. According to the Tukey test, the differences between the 1st interval with either of the other two intervals was significant (both P values&#x2009;=&#x2009;0.000). There were significant differences between Candida albicans with all other organisms (all 5 P values = 0.0000). All other pairwise comparisons were insignificant (all 10 P values&#x2009;&#x2265;&#x2009;0.1). After taking the averages of the 3 intervals, the order of the biofilm generation for different materials were as follows: Detax (average score: 1.56), Easyvac (1.67), Erkodent (1.78), Clear Tech (1.83), BD (2.28).<br><br>CONCLUSIONS: As far as these 6 microorganisms are of concern, there might not be a significant overall difference among the clear retainer materials tested in this study. A significant overall increase was observed between the first and third days, which later did not significantly increase more until day 5. The Candida albicans biofilm was more intense than the tested 5 bacteria, which themselves showed rather similar growth patterns to each other.}, }
@article {pmid39294587, year = {2024}, author = {Chiang-Ni, C and Huang, JY and Hsu, CY and Lo, YC and Chen, YM and Lai, CH and Chiu, CH}, title = {Genetic diversity, biofilm formation, and Vancomycin resistance of clinical Clostridium innocuum isolates.}, journal = {BMC microbiology}, volume = {24}, number = {1}, pages = {353}, pmid = {39294587}, issn = {1471-2180}, support = {CORPD1M0012//Chang Gung Memorial Hospital, Linkou/ ; CORPD1M0012//Chang Gung Memorial Hospital, Linkou/ ; 112-2628-B-182-004//National Science and Technology Council/ ; }, mesh = {*Biofilms/growth &amp; development/drug effects ; Humans ; *Phylogeny ; *Multilocus Sequence Typing ; *Clostridium/genetics/drug effects/isolation &amp; purification/classification ; *Anti-Bacterial Agents/pharmacology ; *Genetic Variation ; *Vancomycin/pharmacology ; *Vancomycin Resistance/genetics ; *Microbial Sensitivity Tests ; *Clostridium Infections/microbiology ; Taiwan ; Genotype ; Genes, Essential ; }, abstract = {BACKGROUND: Clostridium innocuum, previously considered a commensal microbe, is a spore-forming anaerobic bacterium. C. innocuum displays inherent resistance to vancomycin and is associated with extra-intestinal infections, antibiotic-associated diarrhea, and inflammatory bowel disease. This study seeks to establish a multilocus sequence typing (MLST) scheme to explore the correlation between C. innocuum genotyping and its potential pathogenic phenotypes.<br><br>METHODS: Fifty-two C. innocuum isolates from Linkou Chang Gung Memorial Hospital (CGMH) in Taiwan and 60 sequence-available C. innocuum isolates from the National Center for Biotechnolgy Information Genome Database were included. The concentrated sequence of housekeeping genes in C. innocuum was determined by amplicon sequencing and used for MLST and phylogenetic analyses. The biofilm production activity of the C. innocuum isolates was determined by crystal violet staining.<br><br>RESULTS: Of the 112 C. innocuum isolates, 58 sequence types were identified. Maximum likelihood estimation categorized 52 CGMH isolates into two phylogenetic clades. These isolates were found to be biofilm producers, with isolates in clade I exhibiting significantly higher biofilm production than isolates in clade II. The sub-inhibitory concentration of vancomycin seemed to minimally influence biofilm production by C. innocuum isolates. Nevertheless, C. innocuum embedded in the biofilm structure demonstrated resistance to vancomycin treatments at a concentration greater than 256&#xa0;&#xb5;g/mL.<br><br>CONCLUSIONS: This study suggests that a specific genetic clade of C. innocuum produces a substantial amount of biofilm. Furthermore, this phenotype assists C. innocuum in resisting high concentrations of vancomycin, which may potentially play undefined roles in C. innocuum pathogenesis.}, }
@article {pmid39293098, year = {2025}, author = {Lou, X and Zhou, Q and Jiang, Q and Lin, L and Zhu, W and Mei, X and Xiong, J and Gao, Y}, title = {Inhibitory effect and mechanism of violacein on planktonic growth, spore germination, biofilm formation and toxin production of Bacillus cereus and its application in grass carp preservation.}, journal = {International journal of food microbiology}, volume = {426}, number = {}, pages = {110917}, doi = {10.1016/j.ijfoodmicro.2024.110917}, pmid = {39293098}, issn = {1879-3460}, mesh = {*Indoles/pharmacology ; *Bacillus cereus/drug effects/growth &amp; development ; *Biofilms/drug effects/growth &amp; development ; Animals ; *Anti-Bacterial Agents/pharmacology ; *Spores, Bacterial/drug effects/growth &amp; development ; *Bacterial Toxins/biosynthesis/metabolism ; *Carps/microbiology ; *Microbial Sensitivity Tests ; Food Preservation/methods ; Food Microbiology ; Plankton/drug effects/growth &amp; development ; }, abstract = {Bacillus cereus is a ubiquitous foodborne pathogen commonly found in various foods. Its ability to form spores, biofilms and diarrhoeal and/or emetic toxins further exacerbates the risk of food poisoning. Violacein is a tryptophan derivative with excellent antibacterial activity. However, the knowledge on the antibacterial action of violacein against B. cereus was lacking, and thus this study aimed to investigate the antibacterial activity and mechanism. The antibacterial results demonstrated that minimum inhibitory concentration and minimum bactericidal concentration of violacein were 3.125 mg/L and 12.50 mg/L, respectively. Violacein could effectively inhibit planktonic growth, spore germination and biofilm formation of B. cereus (P < 0.001). Meanwhile, violacein significantly downregulated the expression of toxin genes, including nheA (P < 0.05), nheB (P < 0.001), bceT (P < 0.01), cytK (P < 0.001), hblC (P < 0.001) and hblD (P < 0.001). Results of extracellular alkaline phosphatase, nucleotide and protein leakage assays and scanning and transmission electron microscopy observation tests showed violacein destroyed cell walls and membranes of B. cereus. In addition, 6.25 mg/kg of violacein could significantly inhibit B. cereus in grass carp fillets (P < 0.05). These results demonstrate that violacein has great potential as an effective natural antimicrobial preservative to control food contamination and poisoning events caused by B. cereus.}, }
@article {pmid39293097, year = {2025}, author = {Su, LM and Huang, RT and Hsiao, HI}, title = {Biofilm formation comparison of Vibrio parahaemolyticus on stainless steel and polypropylene while minimizing environmental impacts and transfer to grouper fish fillets.}, journal = {International journal of food microbiology}, volume = {426}, number = {}, pages = {110913}, doi = {10.1016/j.ijfoodmicro.2024.110913}, pmid = {39293097}, issn = {1879-3460}, mesh = {*Vibrio parahaemolyticus/growth &amp; development/physiology ; *Stainless Steel ; *Biofilms/growth &amp; development ; *Polypropylenes ; Animals ; Food Microbiology ; Hydrogen-Ion Concentration ; Bacterial Adhesion ; Seafood/microbiology ; Fishes/microbiology ; Temperature ; Food Contamination/prevention &amp; control/analysis ; }, abstract = {This study investigated the influence of food contact surface materials on the biofilm formation of Vibrio parahaemolyticus while attempting to minimize the impact of environmental factors. The response surface methodology (RSM), incorporating three controlled environmental factors (temperature, pH, and salinity), was employed to determine the optimal conditions for biofilm formation on stainless steel (SS) and polypropylene (PP) coupons. The RSM results demonstrated that pH was highly influential. After minimizing the impacts of environmental factors, initially V. parahaemolyticus adhered more rapidly on PP than SS. To adhere to SS, V. parahaemolyticus formed extra exopolysaccharide (EPS) and exhibited clustered stacking. Both PP and SS exhibited hydrophilic properties, but SS was more hydrophilic than PP. Finally, this study observed a higher transfer rate of biofilms from PP to fish fillets than from SS to fish fillets. The present findings suggest that the food industry should consider the material of food processing surfaces to prevent V. parahaemolyticus biofilm formation and thus to enhance food safety.}, }
@article {pmid39289306, year = {2024}, author = {Aydın, F and Aktepe, Y and Kahve, H&#x130; and Çakır, &#x130;}, title = {In Vitro Probiotic Characterization of Yeasts with their Postbiotics' Antioxidant Activity and Biofilm Inhibition Capacity.}, journal = {Current microbiology}, volume = {81}, number = {11}, pages = {364}, pmid = {39289306}, issn = {1432-0991}, support = {121O580//T&#xfc;rkiye Bilimsel ve Teknolojik Ara&#x15f;t&#x131;rma Kurumu/ ; }, mesh = {*Probiotics ; *Biofilms/growth &amp; development ; *Antioxidants/metabolism ; *Yeasts/genetics/physiology/metabolism/classification ; Fermented Foods/microbiology ; Bacteria/classification/genetics/metabolism ; }, abstract = {This study evaluated the in vitro probiotic potential and postbiotic properties of yeast strains isolated from traditional fermented foods, emphasizing antioxidant activity (AOA) and biofilm inhibition capacity (BIC). The yeasts were molecularly confirmed using start codon targeted polymorphisms as Kluyveromyces lactis (n = 17), Saccharomyces cerevisiae (n = 9), Pichia kudriavzevii (n = 6), P. fermentans (n = 4), Wickerhamomyces anomalus (n = 2), and Torulaspora delbrueckii (n = 1). The probiotic assessment of live cells included viability in simulated gastric and pancreatic juices, autoaggregation, hydrophobicity, and AOA, using S. boulardii MYA-796 as reference. Additionally, cell-free supernatants (CFS) were tested for AOA and BIC against Cronobacter sakazakii, Listeria monocytogenes, Pseudomonas aeruginosa, and Staphylococcus aureus. Several strains exhibited significantly higher in vitro probiotic characteristics compared to S. boulardii MYA-796 (P < 0.05), particularly in gastric and pancreatic survival, hydrophobicity, and AOA. Notably, CFS exhibited greater AOA than live cells and strong BIC, especially against L. monocytogenes and S. aureus. Multivariate analysis identified K. lactis TC11, S. cerevisiae M33T1-2, P. kudriavzevii S96, W. anomalus OB7Y1, and T. delbrueckii KY31 as having superior probiotic properties, attributed to enhanced gastric survival, autoaggregation, and AOA. CFS of S. cerevisiae M33T1-2 and T. delbrueckii KY31 demonstrated significant BIC, with over 60% inhibition across all tested pathogens.}, }
@article {pmid39288570, year = {2025}, author = {Liu, X and Ming, Z and Ding, Y and Guan, P and Shao, Y and Wang, L and Wang, X}, title = {Characterization of a novel phage SPX1 and biological control for biofilm of Shewanella in shrimp and food contact surfaces.}, journal = {International journal of food microbiology}, volume = {426}, number = {}, pages = {110911}, doi = {10.1016/j.ijfoodmicro.2024.110911}, pmid = {39288570}, issn = {1879-3460}, mesh = {*Biofilms/growth &amp; development ; *Bacteriophages/physiology/genetics ; Animals ; *Food Microbiology ; *Seafood/microbiology ; Shewanella putrefaciens/virology ; Genome, Viral ; Penaeidae/microbiology ; Food Contamination/prevention &amp; control/analysis ; Shewanella/virology/physiology ; Biological Control Agents ; }, abstract = {Shewanella putrefaciens, commonly found in seafood, forms tenacious biofilms on various surfaces, contributing to spoilage and cross-contamination. Bacteriophages, owing to their potent lytic capabilities, have emerged as novel and safe options for preventing and eliminating contaminants across various foods and food processing environments. In this study, a novel phage SPX1 was isolated, characterized by a high burst size (43.81 ± 3.01 PFU/CFU) and a short latent period (10 min). SPX1 belongs to the Caudoviricetes class, exhibits resistance to chloroform, and sensitivity to ultraviolet. It shows stability over a wide range of temperatures (30-50 °C) and pH levels (3-11). The genome of phage SPX1 consists of 53,428 bp with 49.72 % G + C composition, and lacks tRNAs or virulence factors. Genome analysis revealed the presence of two endolysins, confirming its biofilm-removal capacity. Following the treatment of shrimp surface biofilm with the optimal MOI of 0.001 of phage SPX1 for 5 h, the bacterial count decreased by 1.84 ± 0.1 log10 CFU/cm[2] (> 98.5 %). Biofilms on the surfaces of the three common materials used in shrimp processing and transportation also showed varying degrees of reduction: glass (1.98 ± 0.01 log10 CFU/cm[2]), stainless steel (1.93 ± 0.05 log10 CFU/cm[2]), and polyethylene (1.38 ± 0.1 log10 CFU/cm[2]). The study will contribute to phage as a novel and potent biocontrol agent for effectively managing S. putrefaciens and its biofilm, ensuring a reduction in spoilage bacteria contamination during the aquaculture, processing, and transportation of seafood products.}, }
@article {pmid39287971, year = {2024}, author = {Hassan, AS and Heflen, ES and Nguyen, KD and Parrett, GA and Risser, DD}, title = {EbsA is essential for both motility and biofilm formation in the filamentous cyanobacterium Nostoc punctiforme.}, journal = {Microbiology (Reading, England)}, volume = {170}, number = {9}, pages = {}, pmid = {39287971}, issn = {1465-2080}, mesh = {*Nostoc/genetics/metabolism/physiology/growth &amp; development ; *Biofilms/growth &amp; development ; *Bacterial Proteins/genetics/metabolism ; *Fimbriae, Bacterial/metabolism/genetics ; Gene Expression Regulation, Bacterial ; Gene Deletion ; }, abstract = {Many cyanobacteria, both unicellular and filamentous, exhibit surface motility driven by type IV pili (T4P). While the component parts of the T4P machinery described in other prokaryotes are largely conserved in cyanobacteria, there are also several T4P proteins that appear to be unique to this phylum. One recently discovered component is EbsA, which has been characterized in two unicellular cyanobacteria. EbsA was found to form a complex with other T4P proteins and is essential for motility. Additionally, deletion of ebsA in one of these strains promoted the formation of biofilms. To expand the understanding of ebsA in cyanobacteria, its role in motility and biofilm formation were investigated in the model filamentous cyanobacterium Nostoc punctiforme. Expression of ebsA was strictly limited to hormogonia, the motile filaments of N. punctiforme. Deletion of ebsA did not affect hormogonium development but resulted in the loss of motility and the failure to accumulate surface pili or produce hormogonium polysaccharide (HPS), consistent with pervious observations in unicellular cyanobacteria. Protein-protein interaction studies indicated that EbsA directly interacts with PilB, and the localization of EbsA-GFP resembled that previously shown for both PilB and Hfq. Collectively, these results support the hypothesis that EbsA forms a complex along with PilB and Hfq that is essential for T4P extension. In contrast, rather than enhancing biofilm formation, deletion of both ebsA and pilB abolish biofilm formation in N. punctiforme, implying that distinct modalities for the relationship between motility, T4P function and biofilm formation may exist in different cyanobacteria.}, }
@article {pmid39287559, year = {2024}, author = {Park, J and Hassan, MA and Nabawy, A and Li, CH and Jiang, M and Parmar, K and Reddivari, A and Goswami, R and Jeon, T and Patel, R and Rotello, VM}, title = {Engineered Bacteriophage-Polymer Nanoassemblies for Treatment of Wound Biofilm Infections.}, journal = {ACS nano}, volume = {18}, number = {39}, pages = {26928-26936}, pmid = {39287559}, issn = {1936-086X}, support = {R01 AI134770/AI/NIAID NIH HHS/United States ; R01 EB022641/EB/NIBIB NIH HHS/United States ; }, mesh = {*Biofilms/drug effects ; Animals ; Mice ; *Methicillin-Resistant Staphylococcus aureus/drug effects/virology ; *Polymers/chemistry/pharmacology ; *Anti-Bacterial Agents/pharmacology/chemistry ; Wound Infection/microbiology/therapy/drug therapy ; Bacteriophages ; Hydrogels/chemistry/pharmacology ; Staphylococcus aureus/drug effects/virology/physiology ; Microbial Sensitivity Tests ; Staphylococcal Infections/therapy/drug therapy ; Nanostructures/chemistry ; }, abstract = {The antibacterial efficacy and specificity of lytic bacteriophages (phages) make them promising therapeutics for treatment of multidrug-resistant bacterial infections. Restricted penetration of phages through the protective matrix of biofilms, however, may limit their efficacy against biofilm infections. Here, engineered polymers were used to generate noncovalent phage-polymer nanoassemblies (PPNs) that penetrate bacterial biofilms and kill resident bacteria. Phage K, active against multiple strains of Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA), was assembled with cationic poly(oxanorbornene) polymers into PPNs. The PPNs retained phage infectivity, while demonstrating enhanced biofilm penetration and killing relative to free phages. PPNs achieved 3-log10 bacterial reduction (∼99.9%) against MRSA biofilms in vitro. PPNs were then incorporated into Poloxamer 407 (P407) hydrogels and applied onto in vivo wound biofilms, demonstrating controlled and sustained release. Hydrogel-incorporated PPNs were effective in a murine MRSA wound biofilm model, showing a 1.5-log10 reduction in bacterial load compared to a 0.5 log reduction with phage K in P407 hydrogel. Overall, this work showcases the therapeutic potential of phage K engineered with cationic polymers for treating wound biofilm infections.}, }
@article {pmid39287037, year = {2024}, author = {Ball, C and Jones, H and Thomas, H and Woodmansey, E and Cole, W and Schultz, G}, title = {Impact of continuous topical oxygen therapy on biofilm gene expression in a porcine tissue model.}, journal = {Journal of wound care}, volume = {33}, number = {9}, pages = {702-707}, doi = {10.12968/jowc.2024.0213}, pmid = {39287037}, issn = {0969-0700}, mesh = {Animals ; *Biofilms/drug effects ; *Pseudomonas aeruginosa/drug effects ; Swine ; *Oxygen/metabolism ; Disease Models, Animal ; Pseudomonas Infections/therapy ; Skin/metabolism/microbiology ; Wound Infection/therapy ; Administration, Topical ; Wound Healing ; }, abstract = {OBJECTIVE: The effect of continuous topical oxygen therapy (cTOT) on Pseudomonas aeruginosa biofilm gene transcription profiles following inoculation onto porcine skin, using a customised molecular assay was determined.<br><br>METHOD: Sterilised porcine skin explants were inoculated with Pseudomonas aeruginosa in triplicate: 0 hours as negative control; 24 hours cTOT device on; 24 hours cTOT device off. The oxygen delivery system of the cTOT device was applied to the inoculated tissue and covered with a semi-occlusive dressing. All samples were incubated at 37&#xb1;2&#xb0;C for 24 hours, with the 0 hours negative control inoculated porcine skin samples recovered immediately. Planktonic suspensions and porcine skin biopsy samples were taken at 0 hours and 24 hours. Samples were processed and quantifiably assessed using gene specific reverse transcription-quantitative polymerase chain reaction assays for a panel of eight Pseudomonas aeruginosa genes (16S, pelA, pslA, rsaL, pcrV, pscQ, acpP, cbrA) associated with biofilm formation, quorum sensing, protein secretion/translocation and metabolism.<br><br>RESULTS: Transcriptional upregulation of pelA, pcrV and acpP, responsible for intracellular adhesion, needletip protein production for type-3 secretion systems and fatty acid synthesis during proliferation, respectively, was observed when the cTOT device was switched on compared to when the device was switched off. Data suggest increased metabolic activity within bacterial cells following cTOT treatment.<br><br>CONCLUSION: cTOT is an adjunctive therapy that supports faster healing and pain reduction in non-healing hypoxic wounds. Oxygen has previously been shown to increase susceptibility of biofilms to antibiotics through enhancing metabolism. Observed gene expression changes highlighted the impact of cTOT on biofilms, potentially influencing antimicrobial treatment success in wounds. Further in vitro and clinical investigations are warranted.}, }
@article {pmid39287005, year = {2024}, author = {Miao, ZY and Zhang, XY and Long, HZ and Lin, J and Chen, WM}, title = {Hybrids of 3-Hydroxypyridin-4(1H)-ones and Long-Chain 4-Aminoquinolines as Potent Biofilm Inhibitors of Pseudomonas aeruginosa Potentiate Tobramycin and Polymyxin B Activity.}, journal = {Journal of medicinal chemistry}, volume = {67}, number = {18}, pages = {16835-16857}, doi = {10.1021/acs.jmedchem.4c01760}, pmid = {39287005}, issn = {1520-4804}, mesh = {*Pseudomonas aeruginosa/drug effects ; *Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; Structure-Activity Relationship ; *Tobramycin/pharmacology/chemistry ; Animals ; *Polymyxin B/pharmacology/chemistry ; *Microbial Sensitivity Tests ; *Pseudomonas Infections/drug therapy/microbiology ; Mice ; Drug Synergism ; Quorum Sensing/drug effects ; Pyridones/pharmacology/chemistry/chemical synthesis ; Humans ; Aminoquinolines ; }, abstract = {The biofilm formation of Pseudomonas aeruginosa involves multiple complex regulatory pathways; thus, blocking a single pathway is unlikely to achieve the desired antibiofilm efficacy. Herein, a series of hybrids of 3-hydroxypyridin-4(1H)-ones and long-chain 4-aminoquinolines were synthesized as biofilm inhibitors against P. aeruginosa based on a multipathway antibiofilm strategy. Comprehensive structure-activity relationship studies identified compound 30b as the most valuable antagonist, which significantly inhibited P. aeruginosa biofilm formation (IC50 = 5.8 μM) and various virulence phenotypes. Mechanistic studies revealed that 30b not only targets the three quorum sensing systems but also strongly induces iron deficiency signals in P. aeruginosa. Furthermore, 30b demonstrated a favorable in vitro and in vivo safety profile. Moreover, 30b specifically enhanced the antibacterial activity of tobramycin and polymyxin B in in vitro and in vivo combination therapy. Overall, these results highlight the potential of 30b as a novel anti-infective candidate for treating P. aeruginosa infections.}, }
@article {pmid39283160, year = {2024}, author = {Boren, LS and Grosso, RA and Hugenberg-Cox, AN and Hill, JT and Albert, CM and Tuohy, JM}, title = {Complete genome sequence of Deinococcus sonorensis type strain KR-87: a rare biofilm-producing representative of the genus Deinococcus.}, journal = {Microbiology resource announcements}, volume = {13}, number = {10}, pages = {e0073224}, pmid = {39283160}, issn = {2576-098X}, support = {CTR059401//Arizona Department of Health Services (ADHS)/ ; 1742062//National Science Foundation (NSF)/ ; }, abstract = {Here, we present a complete genome of Deinococcus sonorensis KR-87[T], a biofilm-producing mesophile from the Arizonan Sonoran Desert. The sequence, assembled using Oxford Nanopore Technologies' long-read sequencing platform, predicts a genome size of 4.78 Mbp, with 6 replicons, 4,361 protein-coding genes, and a G+C content of 69.0%.}, }
@article {pmid39283133, year = {2024}, author = {Ng, K-S and Bambace, MF and Andersen, EB and Meyer, RL and Schwab, C}, title = {Environmental pH and compound structure affect the activity of short-chain carboxylic acids against planktonic growth, biofilm formation, and eradication of the food pathogen Salmonella enterica.}, journal = {Microbiology spectrum}, volume = {12}, number = {11}, pages = {e0165824}, pmid = {39283133}, issn = {2165-0497}, support = {NNF21OC0066725//Novo Nordisk Fonden (NNF)/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Salmonella enterica/drug effects/growth &amp; development ; *Carboxylic Acids/pharmacology/chemistry ; Hydrogen-Ion Concentration ; *Anti-Bacterial Agents/pharmacology/chemistry ; Food Microbiology ; Microbial Sensitivity Tests ; Plankton/drug effects/growth &amp; development ; }, abstract = {Short-chain carboxylic acids (SCCAs) that are naturally produced by microbial fermentation play an essential role in delaying microbial spoilage. SCCAs are structurally diverse, but only a few of them are routinely used in food biopreservation. This study investigated the effects of environmental pH and intrinsic properties of 21 structurally different SCCAs on the antimicrobial and antibiofilm activity against Salmonella enterica. Inhibition of SCCA toward planktonic and biofilm growth of S. enterica was higher in an acidic environment (pH 4.5) that is common in fermented products, and for SCCA that possessed both a high acid dissociation strength (pKa) (>4.0) and a positive hydrophobicity [octanol/water partition coefficient (log Kow)]. Crotonic and caproic acids were identified as SCCAs with potential as biopreservatives even at near-neutral pH. SCCA with hydrophilic groups such as lactic acid did not inhibit S. enterica at concentrations up to 50 mM, while SCCA with benzene or methyl groups or a double bond prevented S. enterica growth and biofilm formation. Stimulation of biofilm formation was observed for formic, acetic, and propionic acid close to the minimum inhibitory concentration to reduce 50% of cell density (MIC50) of planktonic cells, and for citric and isocitric acid with an MIC50 of ≥50 mM. The presence of low concentrations of formic and propionic acids during biofilm formation conferred protection during eradication possibly due to a pre-adaptation effect, yet two consecutive acid treatments were successful in eradicating biofilms if the first acid treatment was two- to threefold of the MIC50.IMPORTANCEThis study provides a systematic comparison on the antimicrobial and antibiofilm activity of more than 20 structurally different SCCAs against a common food pathogen. We tested the antimicrobial activity at controlled pH and identified the structure-dependent antimicrobial effects of SCCA without the confounding influence of acidification. The combined effect of pKa and log Kow was identified as an important feature that should be considered when deciding for a specific SCCA in the application as antimicrobial. Our results imply that additional phenomena such as the use of SCCA as substrate and cellular pre-adaption effects have to be taken into consideration. We finally present a two-step treatment as an efficient approach to eradicate biofilms, which can be applied for the disinfection of contact surfaces and manufacturing equipment. Results obtained here can serve as guidelines for application of SCCA to avoid the growth of food pathogens and/or to develop biopreserved food systems.}, }
@article {pmid39282204, year = {2024}, author = {Farzamian, S and Khorsandi, K and Hosseinzadeh, R and Falsafi, S}, title = {Effect of Saponin on Methylene Blue (MB) Photo-Antimicrobial Activity Against Planktonic and Biofilm Form of Bacteria.}, journal = {Indian journal of microbiology}, volume = {64}, number = {3}, pages = {1075-1083}, pmid = {39282204}, issn = {0046-8991}, abstract = {Bacterial resistance has led to the spread of bacterial infections such as chronic wound infections. Finding solutions for combating resistant bacteria in chronic wounds such as Staphylococcus aureus and Pseudomonas aeruginosa became an attractive theme among researchers. P. aeruginosa is a gram negative opportunistic human pathogenic bacterium that is difficult to treat due to its high resistance to antibiotics. S. aureus (gram negative bacterium) also has a high antibiotic resistance, so that it is resistant to vancomycin (VRSA), tetracycline, fluoroquinolones and beta-lactam antibiotics including penicillin and methicillin (MRSA). In particular, S. aureus and P. aeruginosa have intrinsic and acquired antibiotic resistance, making the clinical management of infection a real challenge, especially in patients with comorbidities. aPDT can be proposed as a new method in the treatment of multi-drug resistant bacteria in chronic wound infection conditions. In this study, the effect of saponin (100 μg/mL) on photodynamic inactivation on planktonic and biofilm forms of P. aeruginosa (ATCC 27853) and S. aureus (ATCC 25923) strains and on Human Dermal Fibroblast (HDF) cells was investigated. Methylene blue (MB) was used as photosensitizer (0, 10, 50, 100 μg/mL). The light source was a red LED source (660 nm; power density: 20 mW/cm[2]) which is related to the maximum absorption of MB. The results showed that the use of saponin in combination with MB-aPDT (Methylene Blue-antibacterial photodynamic therapy) reduces the phototoxic activity of MB due to decreasing the monomer form of MB. This result was obtained by spectrophotometric study. Also, the result of MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) assay showed that 8 min of irradiation (660 nm) at 10 μg/mL concentration of alone MB had the lowest phototoxic effect on HDF cells. Due to reduced phototoxic properties of MB in this method, detergents containing saponins not recommended to applied at the same time with MB-aPDT in wound infection area.}, }
@article {pmid39282194, year = {2024}, author = {Biswas, R and Jangra, B and Ashok, G and Ravichandiran, V and Mohan, U}, title = {Current Strategies for Combating Biofilm-Forming Pathogens in Clinical Healthcare-Associated Infections.}, journal = {Indian journal of microbiology}, volume = {64}, number = {3}, pages = {781-796}, pmid = {39282194}, issn = {0046-8991}, abstract = {The biofilm formation by various pathogens causes chronic infections and poses severe threats to industry, healthcare, and society. They can form biofilm on surfaces of medical implants, heart valves, pacemakers, contact lenses, vascular grafts, urinary catheters, dialysis catheters, etc. These biofilms play a central role in bacterial persistence and antibiotic tolerance. Biofilm formation occurs in a series of steps, and any interference in these steps can prevent its formation. Therefore, the hunt to explore and develop effective anti-biofilm strategies became necessary to decrease the rate of biofilm-related infections. In this review, we highlighted and discussed the current therapeutic approaches to eradicate biofilm formation and combat drug resistance by anti-biofilm drugs, phytocompounds, antimicrobial peptides (AMPs), antimicrobial lipids (AMLs), matrix-degrading enzymes, nanoparticles, phagebiotics, surface coatings, photodynamic therapy (PDT), riboswitches, vaccines, and antibodies. The clinical validation of these findings will provide novel preventive and therapeutic strategies for biofilm-associated infections to the medical world.}, }
@article {pmid39282173, year = {2024}, author = {Askari, R and Zaboli, F and Pordeli, H and Kaboosi, H}, title = {Investigation of Photodynamic and Rhamnolipid Inhibition on the Dermatophyte Biofilm.}, journal = {Indian journal of microbiology}, volume = {64}, number = {3}, pages = {927-936}, pmid = {39282173}, issn = {0046-8991}, abstract = {The failure to successfully treat dermatophyte-related diseases is often due to the formation of biofilms, which makes dermatophytes resistant to antifungals. Here, an attempt has been made to assess inhibition of dermatophyte biofilm production using photodynamic therapy and rhamnolipid biosurfactant. Two methods were used to inhibit biofilm formation by dermophytes Trichophyton mentagrophytes, Trichophyton rubrum and Trichophyton verrucosum, Microsporum canis and Microsporum gypseum. The first method was the use of rhamnolipid with concentrations of 39 to 1000 ppm and the second was the use of photodynamic method with concentrations of 8, 16 and 32 µg/ml of methylene blue. In addition, these two methods were evaluated simultaneously. The biofilm formation was evaluated using spectrophotometry and scanning electron microscopy. Biosurfactant has been shown to have an improved ability to inhibit the formation of biofilm by the strains. Although photodynamic therapy has not been successful, but in combination with biosurfactant, it may have a synergistic effect. By investigating the effect of rhamnolipid on the formation of biofilm, it was found that Microsporum species has a relatively stronger attachment to the surfaces of the wells compared to trichophyton species. The biofilms were evaluated with electron microscope in the simultaneous treatment of rhamnolipid and photodynamics. The results showed that after the treatment, the biofilms became discrete and their structural integrity was reduced. Even in Microsporum species, which were among the most resistant dermatophytes, the changes in the fungal biofilm after treatment were significant.}, }
@article {pmid39281025, year = {2024}, author = {He, Z and Zhou, X and Mei, N and Jin, W and Sun, J and Yin, S and Wang, Q}, title = {Effectiveness of cyclic treatment of municipal wastewater by Tetradesmus obliquus - Loofah biofilm, its internal community changes and potential for resource utilization.}, journal = {Water research X}, volume = {24}, number = {}, pages = {100254}, pmid = {39281025}, issn = {2589-9147}, abstract = {Microalgae biofilm has garnered significant attention from researchers in the field of sewage treatment due to its advantages such as ease of collection and stable sewage treatment capabilities. Using agricultural waste as biofilm carriers has become a hotspot in reducing costs for this method. This study first combined Tetradesmus obliquus with loofah to form a microalgae biofilm for the study of periodic nitrogen and phosphorus removal from municipal wastewater. The biofilm could stably treat 7 batches of wastewater within one month. The removal rate of TP almost reached 100 %, while the removal rates of NH4 [+] and TN both reached or exceeded 80 %. The average biomass yield over 25 days was 102.04 mg/L/day. The polysaccharide content increased from 8.61 % to 16.98 % during the cyclic cultivation. The lipid content gradually decreased from 40.91 to 26.1 %. The protein content increased from 32.93 % in the initial stage to 41.18 % and then decreased to 36.31 % in the later stage. During the mid-stage of culturing, the richness of anaerobic bacteria decreased, while the richness of aerobic and facultative bacteria increased, which was conducive to the construction of the microalgae-bacteria symbiotic system and steadily improved the effect of nitrogen and phosphorus removal. As the culturing progressed, the Rotifers that emerged during the mid-stage gradually damaged the biofilm over time, leading to a decline in the effectiveness of sewage treatment in the later stages. This study offers technical support for carrier selection in microalgae biofilm methods and for the periodic removal of nitrogen and phosphorus from wastewater.}, }
@article {pmid39279011, year = {2024}, author = {Silva, MLV and Viana, KSS and de Arruda, JAA and de Miranda, RD and Soares, MCF and Calado, HDR and Amorim, MCL and Costa, FO and Cota, LOM and Abreu, LG and Amaral, TMP and Mesquita, RA}, title = {Volatile sulfur compounds, biofilm, and salivary parameters in patients with periodontal disease: a cross-sectional study.}, journal = {Odontology}, volume = {}, number = {}, pages = {}, pmid = {39279011}, issn = {1618-1255}, support = {CDS-APQ-01835-1//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado de Minas Gerais/ ; }, abstract = {This cross-sectional study aimed to evaluate the interplay between volatile sulfur compounds (VSC), biofilm, salivary parameters, and periodontal status in patients with and without periodontal disease. Sixty-four subjects diagnosed with periodontitis and 60 periodontally healthy individuals were included. Probing depth, clinical attachment level, bleeding on probing, tongue coating index, plaque index, number of teeth, spinnability of unstimulated whole saliva, and salivary flow rate were evaluated. The concentrations of VSC were quantified using a portable gas chromatograph. The mean differences in hydrogen sulfide, methyl mercaptan, salivary flow, spinnability, and plaque index did not exhibit statistically significant variances between the two groups. However, a pronounced tongue coating index and a diminished tooth count showed statistical significance in the periodontitis group (p = 0.039; p < 0.001). Unstimulated salivary flow rate less than 0.25 mL/min was statistically significant in the periodontitis group (p = 0.032). After controlling for confounding factors, bleeding on probing remained significant. A positive correlation between periodontal parameters and VSC concentration was found. An inverse correlation was also noted between the spinnability of saliva and tongue coating index (-0.34; p < 0.001). Salivary parameters may contribute to the formation of tongue coating and are correlated with periodontal status. Bleeding on probing, clinical attachment level, and probing depth were identified as potential contributors to VSC formation.}, }
@article {pmid39278276, year = {2024}, author = {Somawardana, IA and Prasad, B and Kay, W and Hunt, C and Adams, J and Kawaguchi, B and Smith, TB and Ashton, N and Sadaphal, V and Tepper, J and Monogue, M and Ramirez, JI and Jones, OD and Shelton, JM and Evers, BM and Serge, R and Pybus, C and Williams, D and Chopra, R and Greenberg, DE}, title = {Alternating magnetic fields (AMF) and linezolid reduce Staphylococcus aureus biofilm in a large animal implant model.}, journal = {The Journal of infection}, volume = {89}, number = {5}, pages = {106271}, doi = {10.1016/j.jinf.2024.106271}, pmid = {39278276}, issn = {1532-2742}, mesh = {Animals ; *Biofilms/drug effects ; *Linezolid/pharmacology/therapeutic use ; *Staphylococcal Infections/drug therapy/microbiology ; Sheep ; Female ; *Anti-Bacterial Agents/pharmacology/therapeutic use/administration &amp; dosage ; *Prosthesis-Related Infections/microbiology/drug therapy/prevention &amp; control ; Magnetic Fields ; Disease Models, Animal ; Prostheses and Implants/microbiology ; Methicillin-Resistant Staphylococcus aureus/drug effects ; Staphylococcus aureus/drug effects ; Oxazolidinones/pharmacology/therapeutic use/administration &amp; dosage ; }, abstract = {OBJECTIVES: We aimed to evaluate the effectiveness of alternating magnetic fields (AMF) combined with antibiotics in reducing Staphylococcus aureus biofilm on metal implants in a large animal model, compared to antibiotics alone.<br><br>METHODS: Metal plates were inoculated with a clinical MRSA strain and then implanted into thirty-three ewes divided into three groups: positive control, linezolid only, and a combination of linezolid and AMF. Animals had either titanium or cobalt-chrome plates and were sacrificed at 5&#xa0;or 21 days&#xa0;post-implantation. Blood and tissue samples were collected at various time points post-AMF treatment.<br><br>RESULTS: In vivo efficacy studies demonstrated significant biofilm reduction on titanium and cobalt-chrome implants with AMF-linezolid combination treatment compared to controls. Significant bacterial reductions were also observed in surrounding tissues and bones. Cytokine analysis showed improved inflammatory responses with combination therapy, and histopathology confirmed reduced inflammation, necrosis, and bacterial presence, especially at 5 days post-implantation.<br><br>CONCLUSIONS: This study demonstrates that combining AMF with antibiotics significantly reduces biofilm-associated infections on metal implants in a large animal model. Numerical simulations confirmed targeted heating, and in vivo results showed substantial bacterial load reduction and reduced inflammatory response. These findings support the potential of AMF as a non-invasive treatment for prosthetic joint infections.}, }
@article {pmid39277662, year = {2024}, author = {Pumirat, P and Santajit, S and Tunyong, W and Kong-Ngoen, T and Tandhavanant, S and Lohitthai, S and Rungruengkitkun, A and Chantratita, N and Ampawong, S and Reamtong, O and Indrawattana, N}, title = {Impact of AbaI mutation on virulence, biofilm development, and antibiotic susceptibility in Acinetobacter baumannii.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {21521}, pmid = {39277662}, issn = {2045-2322}, support = {Fundamental Fund: fiscal year 2023//Mahidol University/ ; N42A660376//National Research Council of Thailand/ ; }, mesh = {*Acinetobacter baumannii/genetics/drug effects/pathogenicity ; *Biofilms/drug effects/growth &amp; development ; Virulence/genetics ; *Anti-Bacterial Agents/pharmacology ; *Bacterial Proteins/genetics/metabolism ; *Mutation ; *Quorum Sensing/genetics/drug effects ; Gene Expression Regulation, Bacterial/drug effects ; Microbial Sensitivity Tests ; Bacterial Outer Membrane Proteins/genetics/metabolism ; Acinetobacter Infections/microbiology/drug therapy ; Proteomics ; }, abstract = {The quorum sensing (QS) system mediated by the abaI gene in Acinetobacter baumannii is crucial for various physiological and pathogenic processes. In this study, we constructed a stable markerless abaI knockout mutant (ΔabaI) strain using a pEXKm5-based allele replacement method to investigate the impact of abaI on A. baumannii. Proteomic analysis revealed significant alterations in protein expression between the wild type (WT) and ΔabaI mutant strains, particularly in proteins associated with membrane structure, antibiotic resistance, and virulence. Notably, the downregulation of key outer membrane proteins such as SurA, OmpA, OmpW, and BamA suggests potential vulnerabilities in outer membrane integrity, which correlate with structural abnormalities in the ΔabaI mutant strain, including irregular cell shapes and compromised membrane integrity, observed by scanning and transmission electron microscopy. Furthermore, diminished expression of regulatory proteins such as OmpR and GacA-GacS highlights the broader regulatory networks affected by abaI deletion. Functional assays revealed impaired biofilm formation and surface-associated motility in the mutant strain, indicative of altered colonization capabilities. Interestingly, the mutant showed a complex antibiotic susceptibility profile. While it demonstrated increased susceptibility to membrane-targeting antibiotics, its response to beta-lactams was more nuanced. Despite increased expression of metallo-beta-lactamase (MBL) superfamily proteins and DcaP-like protein, the mutant unexpectedly showed lower MICs for carbapenems (imipenem and meropenem) compared to the wild-type strain. This suggests that abaI deletion affects antibiotic susceptibility through multiple, potentially competing mechanisms. Further investigation is needed to fully elucidate the interplay between quorum sensing, antibiotic resistance genes, and overall antibiotic susceptibility in A. baumannii. Our findings underscore the multifaceted role of the abaI gene in modulating various cellular processes and highlight its significance in A. baumannii physiology, pathogenesis, and antibiotic resistance. Targeting the abaI QS system may offer novel therapeutic strategies for this clinically significant pathogen.}, }
@article {pmid39277594, year = {2024}, author = {Su, Z and Xu, D and Hu, X and Zhu, W and Kong, L and Qian, Z and Mei, J and Ma, R and Shang, X and Fan, W and Zhu, C}, title = {Biodegradable oxygen-evolving metalloantibiotics for spatiotemporal sono-metalloimmunotherapy against orthopaedic biofilm infections.}, journal = {Nature communications}, volume = {15}, number = {1}, pages = {8058}, pmid = {39277594}, issn = {2041-1723}, support = {82272512//National Natural Science Foundation of China (National Science Foundation of China)/ ; 82302718//National Natural Science Foundation of China (National Science Foundation of China)/ ; }, mesh = {*Biofilms/drug effects ; Animals ; Mice ; *Manganese Compounds/chemistry/pharmacology ; *Oxygen/metabolism ; *Oxides/pharmacology/chemistry ; Anti-Bacterial Agents/pharmacology ; Hydrogen Peroxide/metabolism ; Immunotherapy/methods ; Humans ; Ultrasonic Therapy/methods ; Nanoparticles/chemistry ; Signal Transduction/drug effects ; Antigens, Bacterial/immunology ; Staphylococcus aureus/drug effects ; Female ; }, abstract = {Pathogen-host competition for manganese and intricate immunostimulatory pathways severely attenuates the efficacy of antibacterial immunotherapy against biofilm infections associated with orthopaedic implants. Herein, we introduce a spatiotemporal sono-metalloimmunotherapy (SMIT) strategy aimed at efficient biofilm ablation by custom design of ingenious biomimetic metal-organic framework (PCN-224)-coated MnO2-hydrangea nanoparticles (MnPM) as a metalloantibiotic. Upon reaching the acidic H2O2-enriched biofilm microenvironment, MnPM can convert abundant H2O2 into oxygen, which is conducive to significantly enhancing the efficacy of ultrasound (US)-triggered sonodynamic therapy (SDT), thereby exposing bacteria-associated antigens (BAAs). Moreover, MnPM disrupts bacterial homeostasis, further killing more bacteria. Then, the Mn ions released from the degraded MnO2 can recharge immune cells to enhance the cGAS-STING signaling pathway sensing of BAAs, further boosting the immune response and suppressing biofilm growth via biofilm-specific T cell responses. Following US withdrawal, the sustained oxygenation promotes the survival and migration of fibroblasts, stimulates the expression of angiogenic growth factors and angiogenesis, and neutralizes excessive inflammation. Our findings highlight that MnPM may act as an immune costimulatory metalloantibiotic to regulate the cGAS-STING signaling pathway, presenting a promising alternative to antibiotics for orthopaedic biofilm infection treatment and pro-tissue repair.}, }
@article {pmid39277052, year = {2024}, author = {Gong, W and Zhang, H and Xue, M and Guo, L and Jiang, M and Zhao, Y and Liang, H}, title = {Electron-deficient wastewater treatment in membrane-aerated conductive biofilm reactor: Performance and mechanism.}, journal = {Bioresource technology}, volume = {413}, number = {}, pages = {131411}, doi = {10.1016/j.biortech.2024.131411}, pmid = {39277052}, issn = {1873-2976}, mesh = {*Biofilms ; *Wastewater/chemistry/microbiology ; *Bioreactors ; *Water Purification/methods ; *Membranes, Artificial ; *Electrons ; *Nitrogen ; Electrodes ; Denitrification ; Oxidoreductases/metabolism ; Oxidation-Reduction ; Electric Conductivity ; Thauera/metabolism ; }, abstract = {A membrane-aerated conductive biofilm reactor (MA-CBR) was constructed for carbon-limited wastewater treatment and to reduce the stress of the electric field on nitrous oxide reductase (NosZ). Counter-diffusion with an embedded aerobic layer declined the effect of current on NosZ (K00376) for N2O reduction. Other coding genes for denitrification in cathodic membrane aerated biofilms, including K02568, K00368, K15864, K02305, and K04561, were also positively affected by the electric field and significantly accumulate in Thauera. NH4[+]-N oxidation can occur at the anode and cathode (membrane aeration biofilm). This cathodic synergistic NH4[+]-N oxidation provided more electrons to be directly utilized by the denitrifying bacteria at the cathode. Compared to the MABR, the total nitrogen removal efficiency of MA-CBR increased by 5.68 mg/L, 11.02 mg/L, and 15.63 mg/L at voltages of 0.25 V, 0.50 V, and 0.75 V, respectively.}, }
@article {pmid39276739, year = {2024}, author = {Zhang, S and Xing, Z and Li, Y and Jiang, L and Shi, W and Zhao, Y and Fang, L}, title = {Plastic film from the source of anaerobic digestion: Surface degradation, biofilm and UV response characteristics.}, journal = {Journal of hazardous materials}, volume = {480}, number = {}, pages = {135793}, doi = {10.1016/j.jhazmat.2024.135793}, pmid = {39276739}, issn = {1873-3336}, mesh = {*Ultraviolet Rays ; Anaerobiosis ; *Plastics/chemistry ; *Biofilms/radiation effects ; *Hydrophobic and Hydrophilic Interactions ; Archaea/radiation effects/metabolism ; Biodegradation, Environmental ; Bacteria/radiation effects/metabolism ; Temperature ; Surface Properties ; }, abstract = {This study simulates a major environmental scenario involving "organic fertilizer source" plastics, by exploring the key factors influencing the changes in plastic-films during anaerobic digestion (AD), as well as the responses of the anaerobically digested plastics to ultraviolet (UV) radiation exposure. The results demonstrate that the degradation effect of AD on plastics is reflected by their yellowish and ruptured appearance, slightly worn surfaces, hardening and opacity, and fragmentation. AD significantly increases the content of oxygen-containing functional groups and the degree of unsaturation in plastic films, with thermophilic temperature processes proving more effective than those conducted at mesophilic temperatures. Exposure to UV light has been found to amplify the degradative effects, suggesting the potential cumulative impact of AD and UV. Both AD and UV irradiation reduced the hydrophilicity of plastics. In particular, the hydrophobicity of polylactic acid films was completely disrupted under overlay-exposure. Furthermore, microbial populations on plastic surfaces were mainly bacterial. These bacterial populations were primarily influenced by temperature, and moderately by the plastic types. In contrast, archaea were predominantly affected by both temperature and digested substrate. This study offers a theoretical foundation for strategies aimed at preventing and controlling plastic pollution derived from organic fertilizers.}, }
@article {pmid39272546, year = {2024}, author = {Kang, S and Yang, Y and Hou, W and Zheng, Y}, title = {Inhibitory Effects of Lactobionic Acid on Biofilm Formation and Virulence of Staphylococcus aureus.}, journal = {Foods (Basel, Switzerland)}, volume = {13}, number = {17}, pages = {}, pmid = {39272546}, issn = {2304-8158}, support = {No. T2023312//Shanghai Agricultural Science and Technology Innovation Program/ ; No. LSNZD201607//Scientific Study Project of the Liaoning Province Education Department/ ; No. 32302257//National Natural Science Foundation of China/ ; }, abstract = {Staphylococcus aureus biofilm is a common bio-contaminant source that leads to food cross-contamination and foodborne disease outbreaks. Hence, there is a need for searching novel antibiofilm agents with potential anti-virulence properties to control S. aureus contamination and infections in food systems. In this study, the antibiofilm effects of lactobionic acid (LBA) against S. aureus and its influence on virulence were explored. The minimum inhibition concentration of LBA on S. aureus was 8 mg/mL. Viable count and crystal violet assays revealed that LBA inhibited and inactivated S. aureus biofilms. Microscopic observations further confirmed the antibiofilm activity of LBA on S. aureus that disrupted the biofilm architecture and inactivated the viable cells in biofilms. Moreover, LBA decreased the release of extracellular DNA (eDNA) and extracellular polysaccharide (EPS) in S. aureus biofilms. LBA suppressed biofilm formation by intervening metabolic activity and reduced virulence secretion by repressing the hemolytic activity of S. aureus. Furthermore, LBA altered the expressions of biofilm- and virulence-related genes in S. aureus, further confirming that LBA suppressed biofilm formation and reduced the virulence secretion of S. aureus. The results suggest that LBA might be useful in preventing and controlling biofilm formation and the virulence of S. aureus to ensure food safety.}, }
@article {pmid39270757, year = {2024}, author = {Vadakkan, K and Hemapriya, J and Ngangbam, AK and Sathishkumar, K and Mapranathukaran, VO}, title = {Biofilm inhibition of Staphylococcus aureus by silver nanoparticles derived from Hellenia speciosa rhizome extract.}, journal = {Microbial pathogenesis}, volume = {196}, number = {}, pages = {106933}, doi = {10.1016/j.micpath.2024.106933}, pmid = {39270757}, issn = {1096-1208}, mesh = {*Biofilms/drug effects ; *Staphylococcus aureus/drug effects ; *Plant Extracts/pharmacology/chemistry ; *Silver/pharmacology/chemistry ; *Metal Nanoparticles/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Rhizome/chemistry ; *Microbial Sensitivity Tests ; Bacterial Adhesion/drug effects ; }, abstract = {Staphylococcus aureus is the most common cause of serious health conditions because of the formation of biofilm, which lowers antibiotic efficacy and enhances infection transmission and tenacious behavior. This bacteria is a major threat to the worldwide healthcare system. Silver nanoparticles have strong antibacterial characteristics and emerged as a possible alternative. This work is most relevant since it investigates the parameters influencing the biogenic nanoparticle-assisted control of bacterial biofilms by Staphylococcus aureus. Nanoparticles were fabricated utilizing Hellenia speciosa rhizome extracts, which largely comprised physiologically active components such as spirost-5-en-3-yl acetate, thymol, stigmasterol, and diosgenin, enhanced with the creation of silver nanocomposites. GC-MS, XRD, DLS, SEM, EDX, FTIR and TEM were used to investigate the characteristics of nanoparticles. The microtiter plate experiment showed that nanoparticles destroyed biofilms by up to 92.41 % at doses that ranged from 0 to 25 μg/ml. Fluorescence microscopy and SEM demonstrated the nanoparticles' capacity to prevent bacterial surface adhesion. EDX research revealed that the organic extract efficiently formed silver nanoparticles with considerable oxygen incorporation, which was attributed to phytochemicals that stabilize AgNPs and prevent accumulation. FTIR spectroscopy indicated the existence of hydroxyl, carbonyl, and carboxylate groups, which are essential for nanoparticle stability. TEM revealed that the AgNPs were spheroidal, with diameters ranging from 40 to 60 nm and an average of 46 nm. These results demonstrate the efficacy of H. speciosa extract in creating stable, well-defined AgNPs suited for a variety of applications. This work underlines the potential of green-synthesized AgNPs in biomedical applications, notably in the treatment of S. aureus biofilm-associated illnesses. The thorough characterization gives important information on the stability and efficiency of these biogenic nanoparticles.}, }
@article {pmid39270755, year = {2024}, author = {Kumbhar, V and Gaiki, S and Shelar, A and Nikam, V and Patil, R and Kumbhar, A and Gugale, G and Pawar, R and Khairnar, B}, title = {Mining for antifungal agents to inhibit biofilm formation of Candida albicans: A study on green synthesis, antibiofilm, cytotoxicity, and in silico ADME analysis of 2-amino-4H-pyran-3-carbonitrile derivatives.}, journal = {Microbial pathogenesis}, volume = {196}, number = {}, pages = {106926}, doi = {10.1016/j.micpath.2024.106926}, pmid = {39270755}, issn = {1096-1208}, mesh = {*Candida albicans/drug effects ; *Biofilms/drug effects ; *Antifungal Agents/pharmacology/chemical synthesis ; *Microbial Sensitivity Tests ; Animals ; Mice ; Pyrans/pharmacology/chemical synthesis/chemistry ; Nitriles/pharmacology/chemical synthesis ; Green Chemistry Technology ; Cell Survival/drug effects ; }, abstract = {Candida albicans (C. albicans) biofilm infections are quite difficult to manage due to their resistance against conventional antifungal drugs. To address this issue, there is a desperate need for new therapeutic drugs. In the present study, a green and efficient protocol has been developed for the synthesis of 2-amino-4H-pyran-3-carbonitrile scaffolds 4a-i, 6a-j, and 8a-g by Knoevenagel-Michael-cyclocondensation reaction between aldehydes, malononitrile, and diverse enolizable C-H activated acidic compounds using guanidinium carbonate as a catalyst either under grinding conditions or by stirring at room temperature. This protocol is operationally simple, rapid, inexpensive, has easy workup and column-free purification. A further investigation of the synthesized compounds was conducted to examine their antifungal potential and their ability to inhibit the growth and development of biofilm-forming yeasts like fungus C. albicans. According to our findings, 4b, 4d, 4e, 6e, 6f, 6g, 6i, 8c, 8d, and 8g were found to be active and potential inhibitors for biofilm infection causing C. albicans. The inhibition of biofilm by active compounds were observed using field emission scanning electron microscopy (FESEM). Biofilm inhibiting compounds were also tested for in vitro toxicity by using 3T3-L1 cell line, and 4b, 6e, 6f, 6g, 6i, 8c, and 8d were found to be biocompatible. Furthermore, the in silico ADME descriptors revealed drug-like properties with no violation of Lipinski's rule of five. Hence, the result suggested that synthesized derivatives could serve as a useful aid in the development of novel antifungal compounds for the treatment of fungal infections and virulence in C. albicans.}, }
@article {pmid39270539, year = {2024}, author = {Roszkowski, P and Bielenica, A and Stefańska, J and Majewska, A and Markowska, K and Pituch, H and Koliński, M and Kmiecik, S and Chrzanowska, A and Struga, M}, title = {Antibacterial and anti-biofilm activities of new fluoroquinolone derivatives coupled with nitrogen-based heterocycles.}, journal = {Biomedicine &amp; pharmacotherapy = Biomedecine &amp; pharmacotherapie}, volume = {179}, number = {}, pages = {117439}, doi = {10.1016/j.biopha.2024.117439}, pmid = {39270539}, issn = {1950-6007}, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Microbial Sensitivity Tests ; *Molecular Docking Simulation ; *Heterocyclic Compounds/pharmacology/chemistry/chemical synthesis ; *Fluoroquinolones/pharmacology/chemistry ; *Nitrogen/chemistry ; DNA Gyrase/metabolism ; Staphylococcus aureus/drug effects ; Ciprofloxacin/pharmacology ; Structure-Activity Relationship ; Bacteria/drug effects/growth &amp; development ; }, abstract = {We report the design, synthesis, and antimicrobial evaluation of a series of ciprofloxacin (CP) conjugates coupled with nitrogen-containing heterocycles. In vitro screening of these new hybrid compounds (1-13) against a panel of planktonic bacterial strains highlighted thiazolyl homologs 6 and 7 as the most promising candidates for further investigation. These derivatives demonstrated potent growth-inhibitory activity against various standard and clinical isolates, with minimum inhibitory concentrations (MICs) ranging from 0.05 to 0.4 µg/ml, which are higher or comparable to the reference fluoroquinolone. Both compounds effectively inhibited biofilm formation by selected staphylococci across all tested concentrations (1-8 x MIC), displaying greater efficacy at higher doses compared to CP alone. Notably, conjugate 7 also significantly eradicated existing biofilms formed by S. aureus of various origin. Molecular docking studies revealed that conjugate 7 engages in a broader range of interactions with DNA gyrase and DNA topoisomerase IV than CP, suggesting stronger binding affinity and enhanced flexibility. This may contribute to its potential in overcoming bacterial resistance mechanisms. The above findings indicate compound 7 as a promising candidate for clinical development.}, }
@article {pmid39269814, year = {2024}, author = {Fakher, S and Westenberg, D}, title = {The anti-biofilm efficacy of copper and zinc doped borate bioactive glasses.}, journal = {Future microbiology}, volume = {19}, number = {14}, pages = {1229-1242}, pmid = {39269814}, issn = {1746-0921}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Copper/pharmacology/chemistry ; *Zinc/pharmacology/chemistry ; *Borates/pharmacology/chemistry ; *Pseudomonas aeruginosa/drug effects/growth &amp; development ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Staphylococcus epidermidis/drug effects ; *Glass/chemistry ; *Escherichia coli/drug effects/growth &amp; development ; Humans ; Microbial Sensitivity Tests ; Cross Infection/prevention &amp; control/microbiology ; Bacteria/drug effects/growth &amp; development ; }, abstract = {Aim: Healthcare-acquired infections (HAIs) pose significant challenges in medical settings due to their resistance to conventional treatment methods. The role of bacterial biofilms in exacerbating these infections is well-documented, making HAIs particularly difficult to eradicate. Despite numerous research efforts, an effective solution to combat these infections remains elusive. This study aims to explore the potential of metal-ion (copper and zinc) doped borate bioactive glasses (BBGs) as a novel treatment modality to inhibit bacterial species commonly implicated in HAIs: Staphylococcus epidermidis, Escherichia coli, and Pseudomonas aeruginosa.Methods: The study analyzed the efficacy of both direct and indirect applications of BBGs on severe biofilms pre-formed under static and dynamic growth conditions; a comprehensive predictive modeling was developed, simulating diverse clinically relevant conditions.Results: Results demonstrate more than 4 log reduction in bacterial growth within 2 days for direct application and 3 days for indirect application of copper and zinc-doped BBGs. These findings were consistent across the three bacterial species, in both static and dynamic conditions.Conclusion: Copper and zinc-doped BBGs can be an effective approach in combating HAIs complicated by biofilms.}, }
@article {pmid39269114, year = {2024}, author = {Zykova, MV and Karpova, MR and Zhang, Y and Chubik, MV and Shunkova, DM and Azarkina, LA and Mihalyov, DA and Konstantinov, AI and Plotnikov, EV and Pestryakov, AN and Perminova, IV and Belousov, MV}, title = {The Influence of Silver-Containing Bionanomaterials Based on Humic Ligands on Biofilm Formation in Opportunistic Pathogens.}, journal = {Nanomaterials (Basel, Switzerland)}, volume = {14}, number = {17}, pages = {}, pmid = {39269114}, issn = {2079-4991}, abstract = {The uncontrolled use of antibiotics has led to a global problem of antimicrobial resistance. One of the main mechanisms of bacterial resistance is the formation of biofilms. In order to prevent the growth of antimicrobial resistance, it is crucial to develop new antibacterial agents that are capable of inhibiting the formation of biofilms. This makes this area of research highly relevant today. Promising candidates for these antibacterial agents are new bionanomaterials made from natural humic substances and silver nanoparticles. These substances have the potential to not only directly kill microorganisms but also penetrate biofilms and inhibit their formation. The goal of this study is to synthesize active pharmaceutical substances in the form of bionanomaterials, using ultradispersed silver nanoparticles in a matrix of coal humic substances, perform their characterization (NMR spectroscopy, TEM, and ICP-AES methods), and research their influence on biofilm formation in the most dangerous opportunistic pathogens (E. coli, Methicillin-resistant St. Aureus, K. pneumoniae, P. aeruginosa, St. aureus, A. baumannii, and K. Pneumonia). The results showed that all of the studied bionanomaterials had antibacterial activity against all of the opportunistic pathogens. Furthermore, they were found to have a suppressive effect on both pre-existing biofilms of these bacteria and their formation.}, }
@article {pmid39267932, year = {2024}, author = {Keyhani, S and Alikhani, MY and Doosti-Irani, A and Shokoohizadeh, L}, title = {Effect of Mentha longifolia essential oil on oqxA efflux pump gene expression and biofilm formation in ciprofloxacin-resistant Klebsiella pneumoniae strains.}, journal = {Iranian journal of microbiology}, volume = {16}, number = {4}, pages = {552-559}, pmid = {39267932}, issn = {2008-3289}, abstract = {BACKGROUND AND OBJECTIVES: Today, medicinal plants and their derivatives are considered to reduce the prevalence of antibiotic resistance. The aim of this study was to investigate the effect of Mentha longifolia essential oil on oqxA efflux pump gene expression and biofilm formation in ciprofloxacin-resistant Klebsiella pneumoniae strains.<br><br>MATERIALS AND METHODS: A total of 50 clinical strains of K. pneumoniae resistant to ciprofloxacin were studied. The minimum inhibitory concentration (MIC) of M. longifolia essential oil and its synergistic effect with ciprofloxacin were determined using the microbroth dilution method and the fractional inhibitory concentration (FIC) method. Minimum biofilm inhibition concentration (MBIC) of M. longifolia essential oil was detected. The effect of essential oils on the expression level of the oqxA gene was detected by Real-time PCR.<br><br>RESULTS: M. longifolia essential oil showed inhibitory activity against ciprofloxacin-resistant strains of K. pneumoniae. When M. longifolia essential oil was combined with ciprofloxacin, the MIC was reduced 2-4 times. In 28% of the strains, M. longifolia with ciprofloxacin showed a synergistic effect. M. longifolia essential oil reduces the strength of biofilm formation and alters the biofilm phenotype. A significant decrease in oqxA gene expression was observed in all isolates after treatment with M. longifolia essential oil.<br><br>CONCLUSION: Based on the results of this study, it was observed that supplementing M. longifolia essential oil can help reduce ciprofloxacin resistance and inhibit biofilm formation in fluoroquinolone-resistant K. pneumoniae strains.}, }
@article {pmid39267929, year = {2024}, author = {Owais, D and Al-Groom, RM and AlRamadneh, TN and Alsawalha, L and Khan, MSA and Yousef, OH and Burjaq, SZ}, title = {Antibiotic susceptibility and biofilm forming ability of Staphylococcus aureus isolated from Jordanian patients with diabetic foot ulcer.}, journal = {Iranian journal of microbiology}, volume = {16}, number = {4}, pages = {450-458}, pmid = {39267929}, issn = {2008-3289}, abstract = {BACKGROUND AND OBJECTIVES: Microbial biofilm is characterized by the irreversible attachment of planktonic cells to a surface and is usually associated with high antimicrobial resistance with worsening the wound healing. The objective of the study was to determine the prevalence of Staphylococcus aureus in diabetic foot ulcers (DFUs) of diabetic patients and to investigate antibiotic susceptibility patterns of these isolates. In addition to screen biofilm forming ability of isolated S. aureus.<br><br>MATERIALS AND METHODS: A total of 112 non-healing wound swabs of diabetic foot patients were collected and cultured on different culture media to identify and characterize 98 isolates. The S. aureus isolates were examined for their antibiotic susceptibility to different antimicrobial agents. Furthermore, S. aureus isolates were evaluated for their biofilm production capability using the Tissue Culture Plate Method (TPC). The level of icaA gene expression was determined by RT-PCR.<br><br>RESULTS: The results of this study showed that these non-healing wounds yield positive cultures, with an average of 1.67 organisms per sample. The isolates showed highest resistance against oxacillin (95.2%) and lowest resistance against linezolid (3.7%). All isolates were biofilm producers and a significant association with the icaA gene expression level was recorded.<br><br>CONCLUSION: This study showed that S. aureus isolates have a great ability to produce biofilms that are associated with the chronicity of wounds in diabetic patients. Routine screening for biofilm formers in chronic wounds and their antibiotic susceptibility testing will help in early treatment and prevent any other complications.}, }
@article {pmid39266450, year = {2024}, author = {Gnimpieba, EZ and Hartman, TW and Do, T and Zylla, J and Aryal, S and Haas, SJ and Agany, DDM and Gurung, BDS and Doe, V and Yosufzai, Z and Pan, D and Campbell, R and Huber, VC and Sani, R and Gadhamshetty, V and Lushbough, C}, title = {Biofilm marker discovery with cloud-based dockerized metagenomics analysis of microbial communities.}, journal = {Briefings in bioinformatics}, volume = {25}, number = {Supplement_1}, pages = {}, pmid = {39266450}, issn = {1477-4054}, support = {#1849206//National Science Foundation/ ; //Institutional Development Award/ ; /GM/NIGMS NIH HHS/United States ; P20GM103443/NH/NIH HHS/United States ; }, mesh = {*Biofilms/growth &amp; development ; *Metagenomics/methods ; Microbiota/genetics ; Cloud Computing ; Humans ; Computational Biology/methods ; }, abstract = {In an environment, microbes often work in communities to achieve most of their essential functions, including the production of essential nutrients. Microbial biofilms are communities of microbes that attach to a nonliving or living surface by embedding themselves into a self-secreted matrix of extracellular polymeric substances. These communities work together to enhance their colonization of surfaces, produce essential nutrients, and achieve their essential functions for growth and survival. They often consist of diverse microbes including bacteria, viruses, and fungi. Biofilms play a critical role in influencing plant phenotypes and human microbial infections. Understanding how these biofilms impact plant health, human health, and the environment is important for analyzing genotype-phenotype-driven rule-of-life functions. Such fundamental knowledge can be used to precisely control the growth of biofilms on a given surface. Metagenomics is a powerful tool for analyzing biofilm genomes through function-based gene and protein sequence identification (functional metagenomics) and sequence-based function identification (sequence metagenomics). Metagenomic sequencing enables a comprehensive sampling of all genes in all organisms present within a biofilm sample. However, the complexity of biofilm metagenomic study warrants the increasing need to follow the Findability, Accessibility, Interoperability, and Reusable (FAIR) Guiding Principles for scientific data management. This will ensure that scientific findings can be more easily validated by the research community. This study proposes a dockerized, self-learning bioinformatics workflow to increase the community adoption of metagenomics toolkits in a metagenomics and meta-transcriptomics investigation. Our biofilm metagenomics workflow self-learning module includes integrated learning resources with an interactive dockerized workflow. This module will allow learners to analyze resources that are beneficial for aggregating knowledge about biofilm marker genes, proteins, and metabolic pathways as they define the composition of specific microbial communities. Cloud and dockerized technology can allow novice learners-even those with minimal knowledge in computer science-to use complicated bioinformatics tools. Our cloud-based, dockerized workflow splits biofilm microbiome metagenomics analyses into four easy-to-follow submodules. A variety of tools are built into each submodule. As students navigate these submodules, they learn about each tool used to accomplish the task. The downstream analysis is conducted using processed data obtained from online resources or raw data processed via Nextflow pipelines. This analysis takes place within Vertex AI's Jupyter notebook instance with R and Python kernels. Subsequently, results are stored and visualized in Google Cloud storage buckets, alleviating the computational burden on local resources. The result is a comprehensive tutorial that guides bioinformaticians of any skill level through the entire workflow. It enables them to comprehend and implement the necessary processes involved in this integrated workflow from start to finish. This manuscript describes the development of a resource module that is part of a learning platform named "NIGMS Sandbox for Cloud-based Learning" https://github.com/NIGMS/NIGMS-Sandbox. The overall genesis of the Sandbox is described in the editorial NIGMS Sandbox [1] at the beginning of this Supplement. This module delivers learning materials on the analysis of bulk and single-cell ATAC-seq data in an interactive format that uses appropriate cloud resources for data access and analyses.}, }
@article {pmid39266402, year = {2024}, author = {Fakeeha, G and AlHarbi, S and Auda, S and Balto, H}, title = {The Impact of Silver Nanoparticles' Size on Biofilm Eradication.}, journal = {International dental journal}, volume = {}, number = {}, pages = {}, doi = {10.1016/j.identj.2024.08.007}, pmid = {39266402}, issn = {1875-595X}, abstract = {INTRODUCTION: Efficient intracanal disinfection is required for a successful regenerative endodontic treatment. Thus, this study aimed to identify the silver nanoparticles' (NPs) size (AgNPs) with the highest antibiofilm efficacy when mixed with calcium hydroxide [Ca(OH)2] to eradicate an in vitro endodontic biofilm.<br><br>METHODS: The various sizes of AgNPs and mixtures were characterized by scanning electron microscopy, transmission electron microscopy, and ultraviolet-visible spectroscopy. A total of 168 dentin root segments were prepared, sterilized, and inoculated for 3 weeks with Actinomyces naeslundii and Fusobacterium nucleatum. Samples were randomly allocated to 4 experimental groups (n = 28/group): 2 nm AgNPs + 35% Ca(OH)2, 5 nm AgNPs + 35% Ca(OH)2, 10 nm AgNPs + 35% Ca(OH)2, and 35% Ca(OH)2 alone. Samples exposed to saline and triple antibiotic paste (TAP) acted as negative and positive control groups, respectively. After 1 and 2 weeks, samples were stained with LIVE/DEAD BacLight dye and examined under a confocal laser scanning microscope to determine the proportion of dead bacteria.<br><br>RESULTS: The characterization procedure revealed a spherical NP's structure with minor aggregations. Except for Ca(OH)2 group, all groups had significantly higher antibiofilm efficacy at 2 weeks. Both the 10 nm mixture (99.5%) and TAP (99.2%) exhibited the highest antibiofilm efficacy at 2 weeks and were not significantly different from one another (P > .05). No significant difference was noted between the 2 and 5 nm mixtures at 1 week (81% and 84%) and 2 weeks (89% and 91%).<br><br>CONCLUSION: The 10 nm AgNPs (0.02%) + 35% Ca(OH)2 mixture exhibited the highest antibiofilm efficacy at 2 weeks compared to all other mixtures at both observation periods. Interestingly, the 10 nm mixture performed similarly to TAP at 2 weeks. Excluding Ca(OH)2 group, longer application significantly improved the antibiofilm efficacy of all tested medicaments.<br><br>CLINICAL RELEVANCE: The 10 nm AgNPs + 35% Ca(OH)2 mixture revealed promising results as an intracanal medicament in the regenerative endodontic treatment protocol.}, }
@article {pmid39264564, year = {2024}, author = {Svitich, OA and Poddubikov, AV and Vartanova, NO and Leonova, AY and Kurbatova, EA}, title = {Biofilm Formation by Lactobacillus Strains of Modern Probiotics and Their Antagonistic Activity against Opportunistic Bacteria.}, journal = {Bulletin of experimental biology and medicine}, volume = {177}, number = {4}, pages = {476-481}, pmid = {39264564}, issn = {1573-8221}, mesh = {*Biofilms/growth &amp; development/drug effects ; *Probiotics/pharmacology ; *Bacterial Adhesion/drug effects ; *Lactobacillus/physiology ; Hydrogen-Ion Concentration ; Culture Media/chemistry ; Lactic Acid/metabolism ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ; Antibiosis/physiology ; Lactobacillus acidophilus/physiology ; }, abstract = {The species identity of the studied lactobacillus strains was confirmed by matrix-activated laser desorption/ionization with time-of-flight ion separation (MALDI-TOF mass spectrometry). Lactobacillus strains differed in the dynamics of lactic acid accumulation and changes in the pH of the culture medium. The culture medium affected adhesion ability of lactobacilli. The ability to adhere does not affect the formation of biofilms by lactobacillus strains except for the L. acidophilus La5 strain, which has low adhesion ability and fewer microbial cells detected after mechanical destruction of the biofilm. The metabiotics of the lactobacillus culture medium have an antagonistic effect on conditionally pathogenic microorganisms. Adhesion, biofilm formation, and antagonistic activity of probiotic lactobacillus strains are strain-specific properties.}, }
@article {pmid39264555, year = {2024}, author = {Niboucha, N and Jubinville, &#xc9; and Péloquin, L and Clop, A and Labrie, S and Goetz, C and Fliss, I and Jean, J}, title = {Reuterin Enhances the Efficacy of Peracetic Acid Against Multi-species Dairy Biofilm.}, journal = {Probiotics and antimicrobial proteins}, volume = {}, number = {}, pages = {}, pmid = {39264555}, issn = {1867-1314}, support = {2016-049-C22//Consortium de Recherche et Innovations en Bioproc&#xe9;d&#xe9;s Industriels au Qu&#xe9;bec/ ; 2016-049-C22//Consortium de Recherche et Innovations en Bioproc&#xe9;d&#xe9;s Industriels au Qu&#xe9;bec/ ; 2016-049-C22//Consortium de Recherche et Innovations en Bioproc&#xe9;d&#xe9;s Industriels au Qu&#xe9;bec/ ; RDCPJ516460-17//Natural Sciences and Engineering Research Council of Canada/ ; RDCPJ516460-17//Natural Sciences and Engineering Research Council of Canada/ ; RDCPJ516460-17//Natural Sciences and Engineering Research Council of Canada/ ; }, abstract = {Biofilms may contain pathogenic and spoilage bacteria and can become a recurring problem in the dairy sector, with a negative impact on product quality and consumer health. Peracetic acid (PAA) is one of the disinfectants most frequently used to control biofilm formation and persistence. Though effective, it cannot be used at high concentrations due to its corrosive effect on certain materials and because of toxicity concerns. The aim of this study was to test the possibility of PAA remaining bactericidal at lower concentrations by using it in conjunction with reuterin (3-hydroxypropionaldehyde). We evaluated the efficacy of PAA in pure form or as BioDestroy[®], a PAA-based commercial disinfectant, on three-species biofilms formed by dairy-derived bacteria, namely Pseudomonas azotoformans PFlA1, Serratia liquefaciens Sl-LJJ01, and Bacillus licheniformis Bl-LJJ01. Minimum inhibitory concentrations of the three agents were determined for each bacterial species and the fractional inhibitory concentrations were then calculated using the checkerboard assay. The minimal biofilm eradication concentration (MBEC) of each antibacterial combination was then calculated against mixed-species biofilm. PAA, BioDestroy[®], and reuterin showed antibiofilm activity against all bacteria within the mixed biofilm at respectively 760 ppm, 450 ppm, and 95.6 mM. The MBEC was lowered significantly to 456 ppm, 337.5 ppm, and 71.7 mM, when exposed to reuterin for 16 h followed by contact with disinfectant. Combining reuterin with chemical disinfection shows promise in controlling biofilm on food contact surfaces, especially for harsh or extended treatments. Furthermore, systems with reuterin encapsulation and nanotechnologies could be developed for sustainable antimicrobial efficacy without manufacturing disruptions.}, }
@article {pmid39264339, year = {2024}, author = {Pradhan, L and Hazra, S and Singh, SV and Bajrang,  and Upadhyay, A and Pal, BN and Mukherjee, S}, title = {Surface modification of medical grade biomaterials by using a low-temperature-processed dual functional Ag-TiO2 coating for preventing biofilm formation.}, journal = {Journal of materials chemistry. B}, volume = {12}, number = {39}, pages = {10093-10109}, doi = {10.1039/d4tb00701h}, pmid = {39264339}, issn = {2050-7518}, mesh = {*Titanium/chemistry/pharmacology ; *Biofilms/drug effects ; *Silver/chemistry/pharmacology ; *Surface Properties ; Animals ; *Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; *Coated Materials, Biocompatible/chemistry/pharmacology ; Metal Nanoparticles/chemistry ; Rats ; Staphylococcus aureus/drug effects/physiology ; Microbial Sensitivity Tests ; Temperature ; Chickens ; Biocompatible Materials/chemistry/pharmacology ; }, abstract = {Biofilm development in medical devices is considered the major virulence component that leads to increased mortality and morbidity among patients. Removing a biofilm once formed is challenging and frequently results in persistent infections. Many current antibiofilm coating strategies involve harsh conditions causing damage to the surface of the medical devices. To address the issue of bacterial attachment in medical devices, we propose a novel antibacterial surface modification approach. In this paper, we developed a novel low-temperature based solution-processed approach to deposit silver nanoparticles (Ag NPs) inside a titanium oxide (TiO2) matrix to obtain a Ag-TiO2 nanoparticle coating. The low temperature (120 °C)-based UV annealed drop cast method is novel and ensures no surface damage to the medical devices. Various medical-grade biomaterials were then coated using Ag-TiO2 to modify the surface of the materials. Several studies were performed to observe the antibacterial and antibiofilm properties of Ag-TiO2-coated medical devices and biomaterials. Moreover, the Ag-TiO2 NPs did not show any skin irritation in rats and showed biocompatibility in the chicken egg model. This study indicates that Ag-TiO2 coating has promising potential for healthcare applications to combat microbial infection and biofilm formation.}, }
@article {pmid39263769, year = {2024}, author = {Blanco Massani, M and To, D and Meile, S and Schmelcher, M and Gintsburg, D and Coraça-Huber, DC and Seybold, A and Loessner, M and Bernkop-Schnürch, A}, title = {Enzyme-responsive nanoparticles: enhancing the ability of endolysins to eradicate Staphylococcus aureus biofilm.}, journal = {Journal of materials chemistry. B}, volume = {12}, number = {37}, pages = {9199-9205}, doi = {10.1039/d4tb01122h}, pmid = {39263769}, issn = {2050-7518}, mesh = {*Staphylococcus aureus/drug effects/physiology ; *Biofilms/drug effects ; *Nanoparticles/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; Humans ; *Microbial Sensitivity Tests ; Endopeptidases/metabolism/pharmacology/chemistry ; Particle Size ; Polyphosphates/chemistry/pharmacology ; }, abstract = {Stimuli-responsive nanomaterials show promise in eradicating Staphylococcus aureus biofilm from implants. Peptidoglycan hydrolases (PGHs) are cationic antimicrobials that can be bioengineered to improve the targeting of persisters and drug-resistant bacteria. However, these molecules can be degraded before reaching the target and/or present limited efficacy against biofilm. Therefore, there is an urgent need to improve their potency. Herein, PGH-polyphosphate nanoparticles (PGH-PP NPs) are formed by ionotropic gelation between cationic PGHs and anionic polyphosphate, with the aim of protecting PHGs and delivering them at the target site triggered by alkaline phosphatase (AP) from S. aureus biofilm. Optimized conditions for obtaining M23-PP NPs and GH15-PP NPs are presented. Size, zeta potential, and transmission electron microscopy imaging confirm the nanoscale size. The system demonstrates outstanding performance, as evidenced by a dramatic reduction in PGHs' minimum inhibitory concentration and minimum bactericidal concentration, together with protection against proteolytic effects, storage stability, and cytotoxicity towards the Caco-2 and HeLa cell lines. Time-kill experiments show the great potential of these negatively charged delivery systems in overcoming the staphylococcal biofilm barrier. Efficacy under conditions inhibiting AP proves the enzyme-triggered delivery of PGHs. The enzyme-responsive PGH-PP NPs significantly enhance the effectiveness of PGHs against bacteria residing in biofilm, offering a promising strategy for eradicating S. aureus biofilm.}, }
@article {pmid39262597, year = {2024}, author = {Pandey, A and Bhushan, J and Joshi, RK and Uppal, AS and Angrup, A and Kansal, S}, title = {Comparative evaluation of antimicrobial efficacy of chitosan nanoparticles and calcium hydroxide against endodontic biofilm of Enterococcus faecalis: An in vitro study.}, journal = {Journal of conservative dentistry and endodontics}, volume = {27}, number = {7}, pages = {750-754}, pmid = {39262597}, issn = {2950-4708}, abstract = {AIM: The aim of the study was to assess and evaluate the antimicrobial effectiveness of chitosan nanoparticles (CSNPs) with calcium hydroxide in the elimination of Enterococcus faecalis.<br><br>MATERIALS AND METHODS: Using the broth microdilution method, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of calcium hydroxide and CSNPs were measured. The antibiofilm effect of calcium hydroxide and CSNPs against E. faecalis biofilm was qualitatively analyzed using a crystal violet assay. A 7-day-old biofilms of E. faecalis grown on dentine discs were assigned to the following three groups (n = 11 dentine discs), normal saline (group I), calcium hydroxide (group II), and CSNPs (group III). Quantification of live and dead cells using confocal microscopy was done to evaluate the antibiofilm efficacy of the medicaments included in the study.<br><br>RESULTS: MIC of calcium hydroxide and CSNPs against E. faecalis was observed at 2.5 mg/mL and 0.31 mg/mL, respectively. MBC of calcium hydroxide and CSNPs was observed at 2.5 mg/mL and 0.31 mg/mL, respectively. Using Crystal Violet (CV) assay, calcium hydroxide and CSNPs showed biofilm inhibition at concentrations of 2.5 mg/mL and 0.625 mg/mL, respectively. Confocal laser scanning microscopy analysis found that both calcium hydroxide and CSNPs showed a significant decrease in viable cells at their MBC values compared to the control group's normal saline. CSNPs showed a significantly lower percentage of live cells than calcium hydroxide (P < 0.05).<br><br>CONCLUSION: The study results reveal that the antimicrobial efficacy of CSNPs is better than calcium hydroxide and normal saline against E. faecalis biofilm.}, }
@article {pmid39261342, year = {2024}, author = {Das, P and Mehra, A and Sachan, SG and Chattopadhyay, S}, title = {Screening different solid supports for Pseudomonas aeruginosa biofilm formation and determining its efficiency for decolorization and degradation of congo red.}, journal = {Archives of microbiology}, volume = {206}, number = {10}, pages = {402}, pmid = {39261342}, issn = {1432-072X}, mesh = {*Biofilms/growth &amp; development ; *Congo Red/metabolism ; *Pseudomonas aeruginosa/physiology/metabolism ; *Biodegradation, Environmental ; Wastewater/microbiology ; Water Pollutants, Chemical/metabolism ; Spectroscopy, Fourier Transform Infrared ; Coloring Agents/metabolism ; Germination ; }, abstract = {A global water crisis is emerging due to increasing levels of contaminated water and decreasing clean water supply on Earth. This study aims to address the removal of azo dye from wastewater to enable its reuse. Recently, utilizing microorganisms has been proven to be a practical choice for the remediation of azo dyes in wastewater. Hence, in this study, we employed a preformed biofilm of Pseudomonas aeruginosa on a solid support (called substrate) to degrade azo dyes. This process offers several advantages, such as stability, substrate portability, more biofilm production in less time, and efficient utilization of enzymes for remediation. From 50 ppm of initial Congo Red concentration, 75.74% decolorization was achieved within ten h using a preformed biofilm on a coverslip. A maximum of 52.27% decolorization was achieved using biofilm during its formation after 72 h of incubation. The Fourier-transform infrared (FTIR) spectroscopic analysis of Congo Red dye before and after remediation revealed a significant change in peak intensity, indicating dye degradation. Phytotoxicity studies performed by seed germination with Vigna radiata revealed that, after 5-7 days, almost 40% more seeds with longer root and shoot lengths were germinated in the presence of treated dye compared to the untreated one. This data indicated that the harmful Congo Red was successfully degraded to a non-toxic product by Pseudomonas aeruginosa biofilm grown on a glass substrate.}, }
@article {pmid39260724, year = {2024}, author = {Ke, Y and Sun, W and Xue, Y and Yuan, Z and Zhu, Y and Chen, X and Yan, S and Li, Y and Xie, S}, title = {Pipe material and natural organic matter impact drinking water biofilm microbial community, pathogen profiles and antibiotic resistome deciphered by metagenomics assembly.}, journal = {Environmental research}, volume = {262}, number = {Pt 2}, pages = {119964}, doi = {10.1016/j.envres.2024.119964}, pmid = {39260724}, issn = {1096-0953}, mesh = {*Biofilms/drug effects ; *Drinking Water/microbiology ; *Metagenomics ; Microbiota/drug effects ; Drug Resistance, Microbial/genetics ; Water Supply ; Anti-Bacterial Agents/pharmacology ; Polyethylene ; Water Microbiology ; }, abstract = {Biofilms in drinking water distribution systems (DWDSs) are a determinant to drinking water biosafety. Yet, how and why pipe material and natural organic matter (NOM) affect biofilm microbial community, pathogen composition and antibiotic resistome remain unclear. We characterized the biofilms' activity, microbial community, antibiotic resistance genes (ARGs), mobile genetic elements (MGEs) and pathogenic ARG hosts in Centers for Disease Control and Prevention (CDC) reactors with different NOM dosages and pipe materials based on metagenomics assembly. Biofilms in cast iron (CI) pipes exhibited higher activity than those in polyethylene (PE) pipes. NOM addition significantly decreased biofilm activity in CI pipes but increased it in PE pipes. Pipe material exerted more profound effects on microbial community structure than NOM. Azospira was significantly enriched in CI pipes and Sphingopyxis was selected in PE pipes, while pathogen (Ralstonia pickettii) increased considerably in NOM-added reactors. Microbial community network in CI pipes showed more edges (CI 13520, PE 7841) and positive correlation proportions (CI 72.35%, PE 61.69%) than those in PE pipes. Stochastic processes drove assembly of both microbial community and antibiotic resistome in DWDS biofilms based on neutral community model. Bacitracin, fosmidomycin and multidrug ARGs were predominant in both PE and CI pipes. Both pipe materials and NOM regulated the biofilm antibiotic resistome. Plasmid was the major MGE co-existing with ARGs, facilitating ARG horizontal transfer. Pathogens (Achromobacter xylosoxidans and Ralstonia pickettii) carried multiple ARGs (qacEdelta1, OXA-22 and aadA) and MGEs (integrase, plasmid and transposase), which deserved more attention. Microbial community contributed more to ARG change than MGEs. Structure equation model (SEM) demonstrated that turbidity and ammonia affected ARGs by directly mediating Shannon diversity and MGEs. These findings might provide a technical guidance for controlling pathogens and ARGs from the point of pipe material and NOM in drinking water.}, }
@article {pmid39259403, year = {2024}, author = {Visperas, A and Cui, K and Alam, MM and Subramanian, S and Butsch, E and Klika, AK and Samia, AC and Piuzzi, NS}, title = {Diamond-like carbon (DLC) surface treatment decreases biofilm burden by S. aureus on titanium alloy in vitro- a pilot study.}, journal = {European journal of orthopaedic surgery &amp; traumatology : orthopedie traumatologie}, volume = {34}, number = {8}, pages = {3989-3994}, pmid = {39259403}, issn = {1432-1068}, mesh = {*Biofilms/drug effects ; *Titanium ; *Staphylococcus aureus/drug effects/physiology ; Pilot Projects ; *Alloys ; *Prosthesis-Related Infections/prevention &amp; control/microbiology ; *Coated Materials, Biocompatible/pharmacology ; Surface Properties ; Microscopy, Electron, Scanning ; Diamond ; Carbon/pharmacology ; Staphylococcal Infections/prevention &amp; control ; Humans ; }, abstract = {PURPOSE: Periprosthetic joint infection is a complication of total joint arthroplasty with treatment costs over $1.6 billion dollars per year in the US with high failure rates. Therefore, generation of coatings that can prevent infection is paramount. Diamond-like carbon (DLC) is an ideal coating for implants as they are wear-resistant, corrosion-resistant, inert, and have a low friction coefficient. The purpose of this study was to test the efficacy of DLC surface treatment in prevention of biofilm on titanium discs infected with Staphylococcus aureus in vitro.<br><br>METHODS: Titanium alloy discs (n&#x2009;=&#x2009;4 non-coated and n&#x2009;=&#x2009;4 DLC-coated) were infected with 5&#x2009;&#xd7;&#x2009;10[5] colony-forming units (CFU) of S. aureus for 2 weeks then analysed via crystal violet and scanning electron microscopy (SEM).<br><br>RESULTS: Crystal violet analysis yielded differences in the appearance of biofilm on implant surface where DLC-coated had a clumpier appearance but no difference in biofilm quantification. Interestingly, this clumpy appearance did lead to differences in SEM biofilm coverage where significantly less biofilm coverage was found on DLC-coated discs (81.78% vs. 54.17%, p&#x2009;<&#x2009;0.003).<br><br>CONCLUSION: DLC-coated titanium alloy implants may have preventative properties in S. aureus infection. Observing differences in biofilm coverage does warrant additional testing including CFU titration and biofilm kinetics with eventual use in an animal model of periprosthetic joint infection.}, }
@article {pmid39257244, year = {2024}, author = {Rajagopal, GK and Raorane, CJ and Ravichandran, V and Rajasekharan, SK}, title = {Synergy of histone acetyltransferase inhibitor (HATi) with quercetin inhibits biofilm formation in Candida tropicalis.}, journal = {Letters in applied microbiology}, volume = {77}, number = {9}, pages = {}, doi = {10.1093/lambio/ovae085}, pmid = {39257244}, issn = {1472-765X}, support = {//SRMIST/ ; }, mesh = {*Candida tropicalis/drug effects ; *Quercetin/pharmacology ; *Biofilms/drug effects ; *Antifungal Agents/pharmacology ; *Histone Acetyltransferases/antagonists &amp; inhibitors/metabolism/genetics ; *Drug Synergism ; *Anacardic Acids/pharmacology ; Drug Resistance, Fungal ; Microbial Sensitivity Tests ; Enzyme Inhibitors/pharmacology ; Fungal Proteins/genetics/metabolism/antagonists &amp; inhibitors ; }, abstract = {Histone acetyltransferase inhibitors (HATi) are mechanism-based inhibitors that show promise in the treatment of several illnesses, including diabetes, hyperlipidemia, cancer, and Alzheimer's disease. The work emphasizes the significance of HATi as a possible treatment strategy against Candida species biofilms. Here, in this study, we found that combining a HATi, anacardic acid (AA), and quercetin, a known flavonoid, significantly prevented biofilm formation by C. tropicalis. We further show that C. tropicalis exhibited a considerable downregulation of drug-resistance gene expression (CDR1 and MDR1) when co-administrated. Additionally, in silico studies revealed that the AA interacts strongly with a histone acetyltransferase, Rtt109, which may account for the observed biofilm inhibitory effect. In conclusion, the study illustrates how HATi may be used to potentiate the inhibitory action of phytoactives or antifungals against drug-resistant yeast infections.}, }
@article {pmid39256439, year = {2024}, author = {de Sousa, DV and Maia, PVS and Eltink, E and de Moura Guimarães, L}, title = {Biomolecules in Pleistocene fossils from tropical cave indicate fossil biofilm.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {21071}, pmid = {39256439}, issn = {2045-2322}, support = {432075/2018-6//Conselho Nacional das Funda&#xe7;&#xf5;es Estaduais de Amparo &#xe0; Pesquisa/ ; 0936-21-52799//Funda&#xe7;&#xe3;o de Amparo &#xe0; Ci&#xea;ncia e Tecnologia do Estado de Pernambuco/ ; 102032/2024-6//Conselho Nacional de Desenvolvimento Cient&#xed;fico e Tecnol&#xf3;gico/ ; }, mesh = {*Fossils ; *Biofilms ; *Spectrum Analysis, Raman ; *Caves/microbiology ; Animals ; Tooth/microbiology/chemistry ; Brazil ; }, abstract = {Finding biomolecules in fossils is a challenging task due to their degradation over time from physical, chemical, and biological factors. The primary hypothesis for explaining the presence of biomolecules in fossilized bones tissues suggests their survival in the fossilization process. In contrast, some of these biomolecules could either derive from bacteria biofilm, thus without a direct relationship with the fossil record or could be an artifact from measurement procedures. Raman spectroscopy studies across various fossil ages and environments have detected multiple bands ranging from 1200 to 1800 cm[-1] associative of organic compounds. However, the significance of these bands remains elusive. Our research aims to address this issue through a deep Raman spectroscopy investigation on Pleistocene teeth from Tayassu and Smilodon populator. These fossils were obtained from a well-preserved stratigraphic succession in Toca de Cima do Pilão cave, near the National Park of Serra da Capivara in semiarid Brazil. We propose two hypotheses to explain the presence of organic compounds related to 1200 to 1800 cm[-1] Raman spectral range in fossil tissues: (i) these bands are biological signatures of preserved fossil biomolecules, or (ii) they are exogenous biological signatures associated with the bacterial biofilm formation during post-depositional processes. Our results align with the latter hypothesis, followed by biofilm degradation. However, the specific mechanisms involved in the natural biofilm degradation in fossil records remain unexplored in this study. In our case, the formation of biofilm on fossil bones is attributed to the oligotrophic conditions of the cave sediment matrix. We present a comprehensive model to elucidate the existence of biofilm on fossilized tissues, emphasizing the pivotal role of post-depositional processes, especially water action, in the cave environment. As the fossils were discovered in a cave setting, post-depositional processes significantly contribute to the formation of the biofilm matrix. Although our study provides insights into biofilm formation, further research is needed to delve into the specific mechanisms driving natural biofilm degradation in fossils.}, }
@article {pmid39255667, year = {2024}, author = {Mei, Z and Wang, F and Fu, Y and Liu, Y and Hashsham, SA and Wang, Y and Harindintwali, JD and Dou, Q and Virta, M and Jiang, X and Deng, Y and Zhang, T and Tiedje, JM}, title = {Biofilm enhanced the mitigations of antibiotics and resistome in sulfadiazine and trimethoprim co-contaminated soils.}, journal = {Journal of hazardous materials}, volume = {479}, number = {}, pages = {135721}, pmid = {39255667}, issn = {1873-3336}, support = {P42 ES004911/ES/NIEHS NIH HHS/United States ; }, mesh = {*Sulfadiazine/pharmacology ; *Biofilms/drug effects ; *Trimethoprim/pharmacology ; *Soil Pollutants/toxicity ; *Anti-Bacterial Agents/pharmacology ; *Soil Microbiology ; *Manure/microbiology ; Arthrobacter/genetics/drug effects/metabolism ; Charcoal ; Genes, Bacterial ; Drug Resistance, Bacterial/genetics ; Drug Resistance, Microbial/genetics ; }, abstract = {Reducing antibiotic levels in soil ecosystems is vital to curb the dissemination of antimicrobial resistance genes (ARGs) and mitigate global health threats. However, gaps persist in understanding how antibiotic resistome can be suppressed during antibiotic degradation. Herein, we investigate the efficacy of a biochar biofilm incorporating antibiotics-degrading bacterial strain (Arthrobacter sp. D2) to mitigate antibiotic resistome in non-manured and manure-amended soils with sulfadiazine (SDZ) and trimethoprim (TMP) contamination. Results show that biofilm enhanced SDZ degradation by 83.0% within three days and increased TMP attenuation by 55.4% over 60 days in non-manured soils. In the non-manured black soil, the relative abundance of ARGs increased initially after biofilm inoculation. However, by day 30, it decreased by 20.5% compared to the controls. Moreover, after 7 days, biofilm reduced TMP by 38.5% in manured soils and decreased the total ARG abundance by 19.0%. Thus, while SDZ degradation did not increase sulfonamide resistance genes, TMP dissipation led to a proliferation of insertion sequences and related TMP resistance genes. This study underscores the importance of antibiotic degradation in reducing related ARGs while cautioning against the potential proliferation and various ARGs transfer by resistant microorganisms.}, }
@article {pmid39254872, year = {2024}, author = {Amer, AM and Charnock, C and Nguyen, S}, title = {Novel Teixobactin Analogues Show Promising In Vitro Activity on Biofilm Formation by Staphylococcus aureus and Enterococcus faecalis.}, journal = {Current microbiology}, volume = {81}, number = {10}, pages = {349}, pmid = {39254872}, issn = {1432-0991}, mesh = {*Biofilms/drug effects ; *Enterococcus faecalis/drug effects/physiology/growth &amp; development ; *Staphylococcus aureus/drug effects/physiology ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Microbial Sensitivity Tests ; *Depsipeptides/pharmacology/chemistry ; }, abstract = {The treatment of infections caused by biofilm-forming organisms is challenging. The newly discovered antibiotic teixobactin shows activity against a wide range of biofilm-forming bacteria. However, the laborious and low-yield chemical synthesis of teixobactin complicates its further development for clinical application. The use of more easily synthesized teixobactin analogues may offer promise in this regard. In this article, three newly developed analogues were tested for efficacy against Staphylococcus aureus and Enterococcus faecalis. Minimum inhibitory and -bactericidal concentrations were investigated. MIC values for S. aureus and E. faecalis ranged from 0.5-2 and 2-4 μg/mL, respectively. Moreover, the ability of the analogues to prevent biofilm formation and to inactivate bacterial cells in already established S. aureus biofilm on medical grade materials (PVC and PTFE) used in the production of infusion tubing and catheters were also tested. The analogues showed an ability to prevent biofilm formation and inactivate bacterial cells in established biofilms at concentrations as low as 1-2 μg/mL. Confocal laser scanning microscopy showed that the most promising analogue (TB3) inactivated S. aureus cells in a preformed biofilm and gave a reduction in biovolume. The relative ease of synthesis of the analogues and their in vitro efficacy, makes them promising candidates for pharmaceutical development.}, }
@article {pmid39252055, year = {2024}, author = {Firouzjaei, MD and Halaji, M and Yaghoubi, S and Hendizadeh, P and Salehi, M and Mohammadi, M and Pournajaf, A}, title = {Inducible clindamycin-resistant and biofilm formation in the Staphylococcus aureus isolated from healthcare worker's anterior nasal carriage.}, journal = {BMC research notes}, volume = {17}, number = {1}, pages = {252}, pmid = {39252055}, issn = {1756-0500}, mesh = {Humans ; *Biofilms/drug effects/growth &amp; development ; *Clindamycin/pharmacology ; *Health Personnel ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; *Staphylococcus aureus/drug effects/isolation &amp; purification/physiology/genetics ; *Methicillin-Resistant Staphylococcus aureus/drug effects/isolation &amp; purification/genetics/physiology ; *Staphylococcal Infections/microbiology/epidemiology ; *Carrier State/microbiology ; Iran ; Male ; Adult ; Female ; Erythromycin/pharmacology ; Drug Resistance, Multiple, Bacterial/genetics ; Drug Resistance, Bacterial/genetics ; }, abstract = {OBJECTIVE: The purpose of this study is a new update on the resistance profile, Macrolide-Lincosamide-Streptogramin B resistance mechanisms and biofilm formation in the Staphylococcus aureus isolated from health care workers (HCWs) nasal carriage at a children's teaching hospital in Babol (Northern Iran).<br><br>RESULTS: A total of 143 non-repetitive nasal swab samples were collected from volunteers, where 53.8% (n; 77/143) were HCWs, 33.6% (n; 48/143) medical students, and 12.6% (n; 18/143) resident students. The prevalence of nasal carriers of S. aureus was 22.4% (n; 32/143), among them, 40.6% (n; 13/32) were identified as methicillin-resistant Staphylococcus aureus (MRSA(carriers. Antimicrobial susceptibility testing showed that erythromycin (68.8%, n; 22/32) and ciprofloxacin (15.6%, n; 5/32) had the highest and lowest resistance rate, respectively. The frequency of resistance genes in the strains was as follows; ermC (n; 17/32, 53.1%), ermA (n; 11/32, 34.4%), ermB (n; 6/32, 18.7%), ereA (n; 3/32, 9.4%). Moreover, 50.0% (n; 16/32), 28.1% (n; 9/32) and 21.8% (n; 7/32) of isolates were strongly, weakly and moderately biofilm producer, respectively. Macrolides-lincosamides-streptogramins B (MLSB) antibiotic resistance among S. aureus isolates from HCWs nasal carriage have found significant prevalence rates throughout the globe. It is crucial to remember that the development of biofilms and MLS B antibiotic resistance are both dynamic processes.}, }
@article {pmid39251105, year = {2024}, author = {Sun, X and Xiao, F and Su, Y and Li, Z and Yu, X and Parales, RE and Li, L}, title = {Cyclic di-GMP incorporates the transcriptional factor FleQ03 in Pseudomonas syringae MB03 to elicit biofilm-dependent resistance in response to Caenorhabditis elegans predation.}, journal = {Journal of invertebrate pathology}, volume = {207}, number = {}, pages = {108189}, doi = {10.1016/j.jip.2024.108189}, pmid = {39251105}, issn = {1096-0805}, mesh = {Animals ; *Caenorhabditis elegans/microbiology ; *Biofilms ; *Cyclic GMP/analogs &amp; derivatives/metabolism ; *Pseudomonas syringae/physiology ; *Bacterial Proteins/genetics/metabolism ; Transcription Factors/genetics/metabolism ; }, abstract = {Bacteria usually form biofilms as a defense mechanism against predation by bacterivorous nematodes. In this context, the second messenger c-di-GMP from the wild-type Pseudomonas syringae MB03 actuates the transcriptional factor FleQ03 to elicit biofilm-dependent nematicidal activity against Caenorhabditis elegans N2. P. syringae MB03 cells exhibited nematicidal activity and c-di-GMP content in P. syringae MB03 cells was increased after feeding to nematodes. Expression of a diguanylate cyclase (DGC) gene in P. syringae MB03 resulted in an increased c-di-GMP content, biofilm yield and nematicidal activity, whereas converse effects were obtained when expressing a phosphodiesterase (PDE) gene. Molecular docking and isothermal titration calorimetry assays verified the affinity activity between c-di-GMP and the FleQ03 protein. The disruption of the fleQ03 gene in P. syringae MB03, while increasing c-di-GMP content, significantly diminished both biofilm formation and nematicidal activity. Interestingly, P. syringae MB03 formed a full-body biofilm around the worms against predation, probably extending from the tail to the head, whereas it was not observed in the fleQ03 gene disrupted cells. Thus, we hypothesized that c-di-GMP incorporated FleQ03 to reinforce bacterial biofilm and biofilm-dependent pathogenicity in response to C. elegans predation, providing insights into a possible means of resisting bacterivorous nematodes by bacteria in natural ecosystems.}, }
@article {pmid39249569, year = {2024}, author = {Ruhal, R and Sahu, A and Koujalagi, T and Das, A and Prasanth, H and Kataria, R}, title = {Biofilm-specific determinants of enterococci pathogen.}, journal = {Archives of microbiology}, volume = {206}, number = {10}, pages = {397}, pmid = {39249569}, issn = {1432-072X}, support = {NA//VIT University/ ; NA//VIT University/ ; NA//VIT University/ ; NA//VIT University/ ; NA//VIT University/ ; NA//VIT University/ ; }, mesh = {*Enterococcus/genetics/metabolism ; *Biofilms ; Gene Expression Regulation, Bacterial ; *Gram-Positive Bacterial Infections/epidemiology/microbiology/physiopathology ; Bacterial Adhesion/genetics ; Adhesins, Bacterial/genetics/metabolism ; Polysaccharides, Bacterial/metabolism ; Gene Transfer, Horizontal ; }, abstract = {Amongst all Enterococcus spp., E. faecalis and E. faecium are most known notorious pathogen and their biofilm formation has been associated with endocarditis, oral, urinary tract, and wound infections. Biofilm formation involves a pattern of initial adhesion, microcolony formation, and mature biofilms. The initial adhesion and microcolony formation involve numerous surface adhesins e.g. pili Ebp and polysaccharide Epa. The mature biofilms are maintained by eDNA, It's worth noting that phage-mediated dispersal plays a prominent role. Further, the involvement of peptide pheromones in regulating biofilm maintenance sets it apart from other pathogens and facilitating the horizontal transfer of resistance genes. The role of fsr based regulation by regulating gelE expression is also discussed. Thus, we provide a concise overview of the significant determinants at each stage of Enterococcus spp. biofilm formation. These elements could serve as promising targets for antibiofilm strategies.}, }
@article {pmid39248307, year = {2024}, author = {Bi, Y and Chen, X and Luo, F and Wang, X and Chen, X and Yao, J and Shao, Z}, title = {Magnetic silk fibroin nanospheres loaded with amphiphilic polypeptides and antibiotics for biofilm eradication.}, journal = {Biomaterials science}, volume = {12}, number = {20}, pages = {5337-5348}, doi = {10.1039/d4bm01065e}, pmid = {39248307}, issn = {2047-4849}, mesh = {*Biofilms/drug effects ; *Fibroins/chemistry/pharmacology ; *Anti-Bacterial Agents/pharmacology/chemistry/administration &amp; dosage ; *Staphylococcus aureus/drug effects/physiology ; *Nanospheres/chemistry ; Peptides/chemistry/pharmacology/administration &amp; dosage ; Microbial Sensitivity Tests ; Drug Carriers/chemistry ; Magnetite Nanoparticles/chemistry ; }, abstract = {The eradication of established biofilms is a highly challenging task, due to the protective barrier effect of extracellular polymeric substances (EPS) and the presence of persister cells. Both increased drug permeability and elimination of persister cells are essential for the eradication of biofilms. Here, magnetic silk fibroin nanospheres loaded with antibiotics and host defense peptide (HDP) mimics (MPSN/S@P) were developed to demonstrate a new strategy for biofilm eradication. As an HDP mimic, an amphiphilic polypeptide containing 90% L-lysine and 10% L-valine (Lys90Val10) was selected for loading onto magnetic silk fibroin nanospheres via electrostatic interactions. Lys90Val10 exhibited excellent antibacterial activities against both planktonic and persister cells of Staphylococcus aureus (S. aureus). As a representative of the hydrophobic drug, spiramycin (SPM) was conveniently embedded into the β-sheet domain during the self-assembly process of silk fibroin. The sustained release of SPM during biofilm eradication enhanced the antibacterial efficacy of MPSN/S@P. The antibacterial test demonstrated that the extract from the MPSN/S@P suspension can kill both planktonic and persister cells of S. aureus, as well as inhibiting biofilm formation. Importantly, with the assistance of magnetic guidance and photothermal effects derived from Fe3O4 nanoparticles (Fe3O4 NPs), over 92% of bacteria in the biofilm were killed by MPSN/S@P, indicating the successful eradication of mature biofilms. The simple preparation method, integration of photothermal and magnetic responsiveness, and persister cell killing functions of MPSN/S@P provide an accessible strategy and illustrative paradigm for efficient biofilm eradication.}, }
@article {pmid39247681, year = {2024}, author = {Cordery, C and Craddock, J and Malý, M and Basavaraja, K and Webb, JS and Walsh, MA and Tews, I}, title = {Control of phosphodiesterase activity in the regulator of biofilm dispersal RbdA from Pseudomonas aeruginosa.}, journal = {RSC chemical biology}, volume = {5}, number = {10}, pages = {1052-1059}, pmid = {39247681}, issn = {2633-0679}, abstract = {The switch between planktonic and biofilm lifestyle correlates with intracellular concentration of the second messenger bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP). While bacteria possess cyclase and phosphodiesterase enzymes to catalyse formation or hydrolysis of c-di-GMP, both enzymatic domains often occur in a single protein. It is tacitly assumed that one of the two enzymatic activities is dominant, and that additional domains and protein interactions enable responses to environmental conditions and control activity. Here we report the structure of the phosphodiesterase domain of the membrane protein RbdA (regulator of biofilm dispersal) in a dimeric, activated state and show that phosphodiesterase activity is controlled by the linked cyclase. The phosphodiesterase region around helices α5/α6 forms the dimer interface, providing a rationale for activation, as this region was seen in contact with the cyclase domain in an auto-inhibited structure previously described. Kinetic analysis supports this model, as the activity of the phosphodiesterase alone is lower when linked to the cyclase. Analysis of a computed model of the RbdA periplasmatic domain reveals an all-helical architecture with a large binding pocket that could accommodate putative ligands. Unravelling the regulatory circuits in multi-domain phosphodiesterases like RbdA is important to develop strategies to manipulate or disperse bacterial biofilms.}, }
@article {pmid39247326, year = {2024}, author = {de Souza, BM and Braga, AS and Vertuan, M and Sassaki, S and Araújo, TT and Santos, PSDS and Buzalaf, MAR and Magalhães, AC}, title = {Influence of irradiated dentin, biofilm and different artificial saliva formulations on root dentin demineralization.}, journal = {Heliyon}, volume = {10}, number = {16}, pages = {e36334}, pmid = {39247326}, issn = {2405-8440}, abstract = {The aim of this study was evaluated the influence of radiation as well as of new formulations of artificial saliva on the development of root dentin lesions. Bovine root samples were divided into: irradiated (70 Gy) dentin or not; the type of biofilm (from irradiated patient-experimental or non-irradiated patient-control) and the type of artificial saliva (for the condition irradiated dentin/biofilm from irradiated patient): Control Artificial Saliva (inorganic); Control Saliva + 1 mg/ml hemoglobin; Control Saliva +0.1 mg/ml cystatin; Control Saliva + hemoglobin + cystatin; Bioextra (positive control) and deionized water (DiW, negative control) (n = 12/group). Biofilm was produced using human biofilm and McBain saliva (0.2 % of sucrose, 37[o] C and 5 % CO2); the treatments were done 1x/day, for 5 days. Colony-forming units (CFU) counting was performed; demineralization was quantified by transversal microradiography. Two-way ANOVA/Bonferroni or Sidak test for the comparison between biofilm x dentin and ANOVA/Tukey or Kruskal-Wallis/Dunn for comparing artificial saliva were done (p < 0.05). The type of biofilm had no influence on CFU and demineralization. Sound dentin under control biofilm presented the lowest Lactobacillus ssp. and Streptococcus mutans CFU and the lowest mean mineral loss (R) (25.6 ± 2.2; 23.7 ± 2.9 %) compared to irradiated dentin (26.1 ± 2.8; 28.1 ± 3.3, p < 0.004) for both types of biofilms (experimental and control, respectively). Bioextra was the only artificial saliva that reduced R (10.8 ± 2.5 %) and Lesion Depth (LD) (35 ± 15 μm) compared to DiW (17.3 ± 3.3 %, 81 ± 18 μm, p < 0.0001). Irradiation has impact on caries development; the experimental saliva were unable to reduce its occurrence.}, }
@article {pmid39246828, year = {2024}, author = {Erb, IK and Suarez, C and Frank, EM and Bengtsson-Palme, J and Lindberg, E and Paul, CJ}, title = {Escherichia coli in urban marine sediments: interpreting virulence, biofilm formation, halotolerance, and antibiotic resistance to infer contamination or naturalization.}, journal = {FEMS microbes}, volume = {5}, number = {}, pages = {xtae024}, pmid = {39246828}, issn = {2633-6685}, abstract = {Marine sediments have been suggested as a reservoir for pathogenic bacteria, including Escherichia coli. The origins, and properties promoting survival of E. coli in marine sediments (including osmotolerance, biofilm formation capacity, and antibiotic resistance), have not been well-characterized. Phenotypes and genotypes of 37 E. coli isolates from coastal marine sediments were characterized. The isolates were diverse: 30 sequence types were identified that have been previously documented in humans, livestock, and other animals. Virulence genes were found in all isolates, with more virulence genes found in isolates sampled from sediment closer to the effluent discharge point of a wastewater treatment plant. Antibiotic resistance was demonstrated phenotypically for one isolate, which also carried tetracycline resistance genes on a plasmid. Biofilm formation capacity varied for the different isolates, with most biofilm formed by phylogroup B1 isolates. All isolates were halotolerant, growing at 3.5% NaCl. This suggests that the properties of some isolates may facilitate survival in marine environments and can explain in part how marine sediments can be a reservoir for pathogenic E. coli. As disturbance of sediment could resuspend bacteria, this should be considered as a potential contributor to compromised bathing water quality at nearby beaches.}, }
@article {pmid39246292, year = {2025}, author = {Shao, L and Li, T and Yang, S and Ma, L and Cai, B and Jia, Q and Jiang, H and Bai, T and Li, Y}, title = {The prebiotic effects of fructooligosaccharides enhance the growth characteristics of Staphylococcus epidermidis and enhance the inhibition of Staphylococcus aureus biofilm formation.}, journal = {International journal of cosmetic science}, volume = {47}, number = {1}, pages = {155-167}, doi = {10.1111/ics.13020}, pmid = {39246292}, issn = {1468-2494}, support = {1021ZK230016013//Shandong Freda Biotech Co., Ltd., and the Collaborative Innovation Center of Fragrance Flavour and Cosmetics/ ; }, mesh = {*Oligosaccharides/pharmacology ; *Staphylococcus epidermidis/drug effects ; *Prebiotics ; *Staphylococcus aureus/drug effects ; *Biofilms/drug effects ; Humans ; Fatty Acids, Volatile/metabolism ; }, abstract = {OBJECTIVE: Oligosaccharides have been shown to enhance the production of short chain fatty acids (SCFAs) by gut probiotics and regulate gut microbiota, to improve intestinal health. Recent research indicates that oligosaccharides may also positively impact skin microbiota by selectively promoting the growth of skin commensal bacteria and inhibiting pathogenic bacteria. However, the specific metabolic and regulatory mechanisms of skin commensal bacteria in response to oligosaccharides remain unclear. This study aims to explore the influence of four oligosaccharides on the growth and metabolism of Staphylococcus epidermidis and further identify skin prebiotics that can enhance its probiotic effects on the skin.<br><br>METHODS: Fructooligosaccharides (FOS), isomaltooligosaccharide (IMO), galactooligosaccharides (GOS) and inulin were compared in terms of their impact on cell proliferation, SCFAs production of S. epidermidis CCSM0287 and the biofilm inhibition effect of their fermentation supernatants on Staphylococcus aureus CCSM0424. Furthermore, the effect of FOS on S. epidermidis CCSM0287 was analysed by the transcriptome analysis.<br><br>RESULTS: All four oligosaccharides effectively promoted the growth of S. epidermidis CCSM0287 cells, increased the production of SCFAs, with FOS demonstrating the most significant effect. Analysis of the SCFAs indicated that S. epidermidis CCSM0287 predominantly employs oligosaccharides to produce acetic acid and isovaleric acid, differing from the SCFAs produced by gut microbiota. Among the four oligosaccharides, the addition of 2% FOS fermentation supernatant significantly inhibited S. aureus CCSM0424 biofilm formation. Furthermore, RNA sequencing revealed 162 differentially expressed genes (84 upregulated and 78 downregulated) of S. epidermidis CCSM0287 upon FOS treatment compared with glucose treatment. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis highlighted differences in the amino acid synthesis pathway, particularly in terms of arginine biosynthesis.<br><br>CONCLUSION: FOS promotes cell proliferation, increases the SCFA production of S. epidermidis CCSM0287 and enhance the inhibition of S. aureus biofilm formation, suggesting that FOS serves as a potential prebiotic for strain S. epidermidis CCSM0287.}, }
@article {pmid39246244, year = {2024}, author = {Saravanan, V and Gopalakrishnan, V and Mahendran, MIMS and Vaithianathan, R and Srinivasan, S and Boopathy, V and Krishnamurthy, S}, title = {Biofilm mediated integrin activation and directing acceleration of colorectal cancer.}, journal = {APMIS : acta pathologica, microbiologica, et immunologica Scandinavica}, volume = {132}, number = {10}, pages = {688-705}, doi = {10.1111/apm.13466}, pmid = {39246244}, issn = {1600-0463}, mesh = {*Biofilms/growth &amp; development ; *Colorectal Neoplasms/microbiology ; Humans ; *Integrins/metabolism ; *Signal Transduction ; }, abstract = {Bacterial biofilm plays a vital role in influencing several diseases, infections, metabolic pathways and communication channels. Biofilm influence over colorectal cancer (CRC) has been a booming area of research interest. The virulence factors of bacterial pathogen have a high tendency to induce metabolic pathway to accelerate CRC. The bacterial species biofilm may induce cancer through regulating the major signalling pathways responsible for cell proliferation, differentiation, survival and growth. Activation of cancer signals may get initiated from the chronic infections through bacterial biofilm species. Integrin mediates in the activation of major pathway promoting cancer. Integrin-mediated signals are expected to be greatly influenced by biofilm. Integrins are identified as an important dimer, whose dysfunction may alter the signalling cascade specially focusing on TGF-β, PI3K/Akt/mToR, MAPK and Wnt pathway. Along with biofilm shield, the tumour gains greater resistance from radiation, chemotherapy and also from other antibiotics. The biofilm barrier is known to cause challenges for CRC patients undergoing treatment.}, }
@article {pmid39245418, year = {2024}, author = {Li, L and Xiong, Y and Zhang, Y and Yan, Y and Zhao, R and Yang, F and Xie, M}, title = {Biofilm-camouflaged Prussian blue synergistic mitochondrial mass enhancement for Alzheimer's disease based on Cu[2+] chelation and photothermal therapy.}, journal = {Journal of controlled release : official journal of the Controlled Release Society}, volume = {375}, number = {}, pages = {269-284}, doi = {10.1016/j.jconrel.2024.09.009}, pmid = {39245418}, issn = {1873-4995}, mesh = {Animals ; *Ferrocyanides/chemistry ; *Alzheimer Disease/drug therapy/therapy ; *Copper/chemistry/administration &amp; dosage ; *Mitochondria/drug effects/metabolism ; *Photothermal Therapy/methods ; *Amyloid beta-Peptides/metabolism ; *Biofilms/drug effects ; *Chelating Agents/chemistry ; *Nanoparticles ; Reactive Oxygen Species/metabolism ; Mice, Transgenic ; Mice ; Humans ; Male ; Blood-Brain Barrier/metabolism ; Erythrocytes/drug effects ; }, abstract = {Alzheimer's disease (AD) is one of the most common neurodegenerative diseases characterized by cognitive and memory impairment. Metal ion imbalance and Mitochondrial dysfunction, leading to abnormal aggregation of β-amyloid protein (Aβ), are key factors in the pathogenesis of AD. Therefore, we designed a composite nanometer system of red blood cell (RBC) membranes-encapsulated Prussian blue nanoparticles (PB/RBC). Prussian blue nanoparticles (PBNPs) can chelate Cu[2+] and reduce reactive oxygen species (ROS). The RBC membranes are a kind of natural long-lasting circulating carrier. At the same time, through NIR irradiation, the excellent photothermal ability of PBNPs can also temporarily open the blood-brain barrier (BBB), enhance the transmission efficiency of PB/RBC across the BBB, and depolymerize the formed Aβ deposits, thereby achieving the optimal therapeutic effect. In vitro and in vivo studies demonstrated that PB/RBC could inhibit Cu[2+]-induced Aβ monomers aggregation, eliminate the deposition of Aβ plaques, improve the quality of mitochondria, restore the phagocytic function of microglia, alleviate neuroinflammation in APP/PS1 mice, and repair memory damage. In conclusion, our biofilm-camouflaged nano-delivery system provides significant neuroprotection by inhibiting Cu[2+]-induced Aβ monomers aggregation, photothermally depolymerizing Aβ fibrils and reducing the level of ROS, thus effectively ameliorating and treating AD.}, }
@article {pmid39244811, year = {2025}, author = {Maggio, F and Rossi, C and Serio, A and Chaves-Lopez, C and Casaccia, M and Paparella, A}, title = {Anti-biofilm mechanisms of action of essential oils by targeting genes involved in quorum sensing, motility, adhesion, and virulence: A review.}, journal = {International journal of food microbiology}, volume = {426}, number = {}, pages = {110874}, doi = {10.1016/j.ijfoodmicro.2024.110874}, pmid = {39244811}, issn = {1879-3460}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Quorum Sensing/drug effects ; *Oils, Volatile/pharmacology ; Virulence ; *Bacterial Adhesion/drug effects ; Bacteria/drug effects/pathogenicity/genetics ; Anti-Bacterial Agents/pharmacology ; Gene Expression Regulation, Bacterial/drug effects ; }, abstract = {Biofilms are a critical factor for food safety, causing important economic losses. Among the novel strategies for controlling biofilms, essential oils (EOs) can represent an environmentally friendly approach, able to act both on early and mature stages of biofilm formation. This review reports the anti-biofilm mechanisms of action of EOs against five pathogenic bacterial species known for their biofilm-forming ability. These mechanisms include disturbing the expression of genes related to quorum sensing (QS), motility, adhesion, and virulence. Biofilms and QS are interconnected processes, and EOs interfere with the communication system (e.g. regulating the expression of agrBDCA, luxR, luxS, and pqsA genes), thus influencing biofilm formation. In addition, QS is an important mechanism that regulates gene expression related to bacterial survival, virulence, and pathogenicity. Similarly, EOs also influence the expression of many virulence genes. Moreover, EOs exert their effects modulating the genes associated with bacterial adhesion and motility, for example those involved in curli (csg), fimbriae (fim, lpf), and flagella (fla, fli, flh, and mot) production, as well as the ica genes responsible for synthetizing polysaccharide intercellular adhesin. This review provides a comprehensive framework on the topic for a better understanding of EOs biofilm mechanisms of action.}, }
@article {pmid39244761, year = {2024}, author = {Cui, Y and Wang, D and Zhang, L and Qu, X}, title = {Research progress on the regulatory mechanism of biofilm formation in probiotic lactic acid bacteria.}, journal = {Critical reviews in food science and nutrition}, volume = {}, number = {}, pages = {1-15}, doi = {10.1080/10408398.2024.2400593}, pmid = {39244761}, issn = {1549-7852}, abstract = {Probiotic lactic acid bacteria (LAB) must undergo three key stages of testing, including food processing, storage, and gastrointestinal tract environment, their beneficial effects could exert. The biofilm formation of probiotic LAB is helpful for improving their stress resistances, survival rates, and colonization abilities under adverse environmental conditions, laying an important foundation for their probiotic effects. In this review, the formation process, the composition and function of basic components of probiotic LAB biofilm have been summarized. This review focuses on the regulatory mechanism of probiotic LAB biofilm formation. In addition, the characteristics and related mechanisms of probiotics in biofilm state have been analyzed to guide the application of probiotic LAB biofilms in the field of health and food. The biofilm formation of LAB is an extremely complex process involving multiple regulatory factors. Besides quorum sensing (QS), other regulatory factors are not yet fully understood. The probiotic LAB in biofilm state exhibit superior survival rate, adhesion performance, and immunomodulation ability, attribute to various metabolic processes, including stress response, exopolysaccharide (EPS) metabolism, amino acid and protein metabolisms, etc. The understanding about regulatory mechanism of biofilm formation of different probiotic species and strains will accelerate the development and application of probiotics products.}, }
@article {pmid39244528, year = {2024}, author = {Feng, R and Chen, Y and Chen, T and Hu, Z and Peng, T}, title = {DUF1127-containing protein and ProQ had opposite effects on biofilm formation in Vibrio alginolyticus.}, journal = {BMC microbiology}, volume = {24}, number = {1}, pages = {330}, pmid = {39244528}, issn = {1471-2180}, support = {42276158//National Natural Science Foundation of China/ ; 2024A1515010759//Guang dong Natural Science Foundation-General Project/ ; KYY24053//Initial Funding of Jiangsu University of Technology/ ; }, mesh = {*Biofilms/growth &amp; development ; *Vibrio alginolyticus/genetics/physiology/metabolism ; *Bacterial Proteins/genetics/metabolism ; *Gene Expression Regulation, Bacterial ; *Oxidative Stress ; RNA-Binding Proteins/genetics/metabolism ; Virulence/genetics ; Gene Deletion ; Reactive Oxygen Species/metabolism ; }, abstract = {The RNA binding protein is crucial for gene regulation at the post transcription level. In this study, functions of the DUF1127-containing protein and ProQ, which are RNA-binding proteins, were revealed in Vibrio alginolyticus. DUF1127 deletion increased the ability of biofilm formation, whereas ProQ deletion reduced the amount of biofilm. Moreover, extracellular proteinase secretion was significantly reduced in the DUF1127 deletion strain. ProQ, not DUF1127-containing protein, can help the cell to defense oxidative stress. Deletion of DUF1127 resulted in a higher ROS level in the cell, however, ProQ deletion showed no difference. RNA-seq unveiled the expression of genes involved in extracellular protease secretion were significantly downregulated and biofilm synthesis-related genes, such as rbsB and alsS, were differentially expressed in the DUF1127 deletion strain. ProQ affected the expression of genes involved in biofilm synthesis (flgC and flgE), virulence (betB and hutG), and oxidative stress. Moreover, the DUF1127-containing and ProQ affected the mRNA levels of various regulators, such as LysR and BetI. Overall, our study revealed that the DUF1127-containing protein and ProQ have crucial functions on biofilm formation in V. alginolyticus.}, }
@article {pmid39244368, year = {2024}, author = {Yao, S and Yang, H and Zhang, M and Xian, J and Zhou, R and Jin, Y and Huang, J and Wu, C}, title = {Sucrose contributed to the biofilm formation of Tetragenococcus halophilus and changed the biofilm structure.}, journal = {Food microbiology}, volume = {124}, number = {}, pages = {104616}, doi = {10.1016/j.fm.2024.104616}, pmid = {39244368}, issn = {1095-9998}, mesh = {*Biofilms/growth &amp; development ; *Sucrose/metabolism ; Polysaccharides, Bacterial/metabolism ; Enterococcaceae/genetics/metabolism/physiology ; Bacterial Proteins/genetics/metabolism ; Monosaccharides/metabolism ; Gene Expression Regulation, Bacterial ; Freeze Drying ; }, abstract = {Based on the previous research results that the addition of sucrose in the medium improved the biofilm formation of Tetragenococcus halophilus, the influence of sucrose on biofilm formation was explored. Moreover, the influence of exogenous expression of related genes sacA and galE from T. halophilus on the biofilm formation of L. lactis NZ9000 was investigated. The results showed that the addition of sucrose in the medium improved the biofilm formation, the resistance of biofilm cells to freeze-drying stress, and the contents of exopolysaccharides (EPS) and eDNA in the T. halophilus biofilms. Meanwhile, the addition of sucrose in the medium changed the monosaccharide composition of EPS and increased the proportion of glucose and galactose in the monosaccharide composition. Under 2.5% (m/v) salt stress condition, the expression of gene sacA promoted the biofilm formation and the EPS production of L. lactis NZ9000 with the sucrose addition in the medium and changed the EPS monosaccharide composition. The expression of gene galE up-regulated the proportion of rhamnose, galactose, and arabinose in the monosaccharide composition of EPS, and down-regulated the proportion of glucose and mannose. This study will provide a theoretical basis for regulating the biofilm formation of T. halophilus, and provide a reference for the subsequent research on lactic acid bacteria biofilms.}, }
@article {pmid39244358, year = {2024}, author = {Yi, Y and Chen, M and Coldea, TE and Yang, H and Zhao, H}, title = {Soy protein hydrolysates induce menaquinone-7 biosynthesis by enhancing the biofilm formation of Bacillus subtilis natto.}, journal = {Food microbiology}, volume = {124}, number = {}, pages = {104599}, doi = {10.1016/j.fm.2024.104599}, pmid = {39244358}, issn = {1095-9998}, mesh = {*Bacillus subtilis/metabolism/genetics/physiology ; *Biofilms/growth &amp; development ; *Vitamin K 2/analogs &amp; derivatives/metabolism ; *Fermentation ; *Protein Hydrolysates/metabolism ; *Soybean Proteins/metabolism ; Bacterial Proteins/metabolism/genetics ; Quorum Sensing ; }, abstract = {Menaquinone-7 (MK-7) is a form of vitamin K2 with health-beneficial effects. A novel fermentation strategy based on combining soy protein hydrolysates (SPHs) with biofilm-based fermentation was investigated to enhance menaquinone-7 (MK-7) biosynthesis by Bacillus subtilis natto. Results showed the SPHs increased MK-7 yield by 199.4% in two-stage aeration fermentation as compared to the SP-based medium in submerged fermentation, which was related to the formation of robust biofilm with wrinkles and the enhancement of cell viability. Moreover, there was a significant correlation between key genes related to MK-7 and biofilm synthesis, and the quorum sensing (QS) related genes, Spo0A and SinR, were downregulated by 0.64-fold and 0.39-fold respectively, which promoted biofilm matrix synthesis. Meanwhile, SPHs also enhanced the MK-7 precursor, isoprene side chain, supply, and MK-7 assembly efficiency. Improved fermentation performances of bacterial cells during fermentation were attributed to abundant oligopeptides (Mw < 1 kDa) and moderate amino acids, particularly Arg, Asp, and Phe in SPHs. All these results revealed that SPHs were a potential and superior nitrogen source for MK-7 production by Bacillus subtilis natto.}, }
@article {pmid39244072, year = {2024}, author = {Hou, S and Li, Y and Chen, Q and Yang, J and Zhao, P and Zhao, Y}, title = {Mechano-triggered eradication of dentinal tubule biofilm via in situ generation of nanoscale sonosensitizer by the tailored irrigation formulation.}, journal = {International journal of pharmaceutics}, volume = {665}, number = {}, pages = {124655}, doi = {10.1016/j.ijpharm.2024.124655}, pmid = {39244072}, issn = {1873-3476}, mesh = {*Biofilms/drug effects ; *Dentin/drug effects ; Animals ; Mice ; *Indocyanine Green/administration &amp; dosage/pharmacology/chemistry ; *Hydrogen Peroxide ; *Anti-Bacterial Agents/pharmacology/administration &amp; dosage/chemistry ; Cell Line ; Humans ; Root Canal Irrigants/pharmacology/administration &amp; dosage ; Ferrous Compounds/chemistry/pharmacology ; Sodium Hypochlorite/pharmacology ; Metallocenes/chemistry ; Nanoparticles/chemistry ; }, abstract = {The efficient elimination of bacteria within the dentinal tubules has been hindered by the poor deposition and short residence of disinfecting agents. Meanwhile, the current irrigant (e.g., NaClO, 5.25 %) shows severe adverse effects on the surrounding soft tissues because of its inherent high irritancy. To address this issue, this work reports an in situ generated sonosensitizer to handle the biofilm in dentinal tubules with minimal adverse effects. The production of nanoscale sonosensitizer involves the concurrent delivery of H2O2 (0.01 %), ferrocene derivative (Fc), and indocyanine green (ICG). With ultrasound treatment, the reaction between H2O2 and Fc liberated Fe[3+] that was further complexed with ICG to generate the nanoscale sonosensitizer in situ, followed by singlet oxygen production for potent disinfecting action. Because the above cascade reactions occur within the confined dentinal tubules, the generated ICG-Fe[3+] nanosensitizer would show prolonged retention therein. The anti-bacterial potency of nanosensitizer was demonstrated in petrodish and ex vivo biofilm models. Meanwhile, the transmission electron microscope imaging of biofilm and cytotoxicity assay in L929 fibroblast cells proved the superiority of nanosensitizer against NaClO regarding adverse effects. The current work opens new avenues of biofilm elimination in dentinal tubules, showing a high translation potential.}, }
@article {pmid39243653, year = {2024}, author = {Yan, Z and Chen, Y and Su, P and Liu, S and Jiang, R and Wang, M and Zhang, L and Lu, G and Yuan, S}, title = {Microbial carbon metabolism patterns of microplastic biofilm in the vertical profile of urban rivers.}, journal = {Journal of environmental management}, volume = {370}, number = {}, pages = {122422}, doi = {10.1016/j.jenvman.2024.122422}, pmid = {39243653}, issn = {1095-8630}, mesh = {*Biofilms ; *Rivers/microbiology ; *Carbon/metabolism ; *Microplastics ; Water Pollutants, Chemical/metabolism ; }, abstract = {Microplastics (MPs) can provide a unique niche for microbiota in waters, thus regulating the nutrients and carbon cycling. Following the vertical transport of MPs in waters, the compositions of attached biofilm may be dramatically changed. However, few studies have focused on the related ecological function response, including the carbon metabolism. In this study, we investigated the microbial carbon metabolism patterns of attached biofilm on different MPs in the vertical profile of urban rivers. The results showed that the carbon metabolism capacity of biofilm on the degradable polylactic acid (PLA) MPs was higher than that in the non-degradable polyethylene terephthalate (PET) MPs. In the vertical profile, the carbon metabolism rates of biofilm on two MPs both decreased with water depth, being 0.74 and 0.91 folds in bottom waters of that in surface waters. Specifically, the utilization of polymers, carbohydrate, and amine of PLA biofilm was significantly inhibited in the bottom waters, which were not altered on the PET. Compared with surface waters, the microbial metabolism function index of PLA biofilm was inhibited in deep waters, but elevated in the PET biofilm. In addition, the water quality parameters (e.g., nutrients) in the vertical profile largely shaped carbon metabolism patterns. These findings highlight the distinct carbon metabolism patterns in aquatic environments in the vertical profile, providing new insights into the effects of MPs on global carbon cycle.}, }
@article {pmid39242535, year = {2024}, author = {Attrah, M and Schärer, MR and Esposito, M and Gionchetta, G and Bürgmann, H and Lens, PNL and Fenner, K and van de Vossenberg, J and Robinson, SL}, title = {Disentangling abiotic and biotic effects of treated wastewater on stream biofilm resistomes enables the discovery of a new planctomycete beta-lactamase.}, journal = {Microbiome}, volume = {12}, number = {1}, pages = {164}, pmid = {39242535}, issn = {2049-2618}, support = {109070/WT_/Wellcome Trust/United Kingdom ; Schweizerischer Nationalfonds zur F&#xf6;rderung der Wissenschaftlichen Forschung, 186531 (ANTIVERSA as part of biodeversa+, European Biodiversity Partnership)//Schweizerischer Nationalfonds zur F&#xf6;rderung der Wissenschaftlichen Forschung/ ; Schweizerischer Nationalfonds zur F&#xf6;rderung der Wissenschaftlichen Forschung, 186531 (ANTIVERSA as part of biodeversa+, European Biodiversity Partnership)//Schweizerischer Nationalfonds zur F&#xf6;rderung der Wissenschaftlichen Forschung/ ; 200021L_201006//Schweizerischer Nationalfonds zur F&#xf6;rderung der Wissenschaftlichen Forschung/ ; PZPGP2_209124//Schweizerischer Nationalfonds zur F&#xf6;rderung der Wissenschaftlichen Forschung/ ; }, mesh = {*Biofilms/drug effects ; *Wastewater/microbiology ; *beta-Lactamases/genetics ; *Rivers/microbiology ; *Metagenomics ; Microbiota/drug effects ; Bacteria/genetics/classification/drug effects/isolation &amp; purification ; Anti-Bacterial Agents/pharmacology ; Planctomycetales/genetics/drug effects ; Metagenome ; Bacterial Proteins/genetics/metabolism ; }, abstract = {BACKGROUND: Environmental reservoirs of antibiotic resistance pose a threat to human and animal health. Aquatic biofilms impacted by wastewater effluent (WW) are known environmental reservoirs for antibiotic resistance; however, the relative importance of biotic factors and abiotic factors from WW on the abundance of antibiotic resistance genes (ARGs) within aquatic biofilms remains unclear. Additionally, experimental evidence is limited within complex aquatic microbial communities as to whether genes bearing low sequence similarity to validated reference ARGs are functional as ARGs.<br><br>RESULTS: To disentangle the effects of abiotic and biotic factors on ARG abundances, natural biofilms were previously grown in flume systems with different proportions of stream water and either ultrafiltered or non-ultrafiltered WW. In this study, we conducted deep shotgun metagenomic sequencing of 75 biofilm, stream, and WW samples from these flume systems and compared the taxonomic and functional microbiome and resistome composition. Statistical analysis revealed an alignment of the resistome and microbiome composition and a significant association with experimental treatment. Several ARG classes exhibited an increase in normalized metagenomic abundances in biofilms grown with increasing percentages of non-ultrafiltered WW. In contrast, sulfonamide and extended-spectrum beta-lactamase ARGs showed greater abundances in biofilms grown in ultrafiltered WW compared to non-ultrafiltered WW. Overall, our results pointed toward the dominance of biotic factors over abiotic factors in determining ARG abundances in WW-impacted stream biofilms and suggested gene family-specific mechanisms for ARGs that exhibited divergent abundance patterns. To investigate one of these specific ARG families experimentally, we biochemically characterized a new beta-lactamase from the Planctomycetota (Phycisphaeraceae). This beta-lactamase displayed activity in the cleavage of cephalosporin analog despite sharing a low sequence identity with known ARGs.<br><br>CONCLUSIONS: This discovery of a functional planctomycete beta-lactamase ARG is noteworthy, not only because it was the first beta-lactamase to be biochemically characterized from this phylum, but also because it was not detected by standard homology-based ARG tools. In summary, this study conducted a metagenomic analysis of the relative importance of biotic and abiotic factors in the context of WW discharge and their impact on both known and new ARGs in aquatic biofilms. Video Abstract.}, }
@article {pmid39242261, year = {2024}, author = {Carmona-Orozco, ML and Echeverri, F}, title = {Corrigendum to "Induction of biofilm in extended-spectrum beta-lactamase Staphylococcus aureus with drugs commonly used in pharmacotherapy" [Microb Pathog 195 (2024) 106863 1-11].}, journal = {Microbial pathogenesis}, volume = {195}, number = {}, pages = {106911}, doi = {10.1016/j.micpath.2024.106911}, pmid = {39242261}, issn = {1096-1208}, }
@article {pmid39925837, year = {2024}, author = {Elhaig, MM and El-Tarabili, RM and Wahdan, A}, title = {A report of coagulase-negative Staphylococci from clinically incurable cases of bovine mastitis: prevalence, biofilm formation, and resistance profile.}, journal = {Iranian journal of veterinary research}, volume = {25}, number = {3}, pages = {279-284}, pmid = {39925837}, issn = {1728-1997}, abstract = {BACKGROUND: Given the abuse of broad-spectrum agents in the treatment of clinical bovine mastitis, coagulase-negative Staphylococci (CNS) have emerged to be of clinical and epidemiological significance.<br><br>AIMS: The study aimed to identify CNS and Staphylococcus aureus in incurable clinical mastitis in 50 cattle and 90 buffaloes, determine antibiotic resistance profile, and biofilm-forming ability of CNS and S. aureus isolates.<br><br>METHODS: 140 milk samples were collected from four villages in Sharkia, Egypt, for bacteriological isolation and molecular investigations.<br><br>RESULTS: Forty-nine Staphylococcus isolates were identified, including 11 CNS and 38 coagulase-positive S. aureus. The most recorded CNS strains were S. epidemidis (3), S. simulans (2), S. hominis (2), S. chromogen (2), S. xylosus (1), and S. warneri (1). A 63.2% of S. aureus and 27.3% of CNS isolates showed the ability to form biofilm, which was confirmed by ica PCR. S. epidemidis and S. chromogen were extensively drug-resistant, and most S. aureus isolates showed multidrug resistance (MDR). The proportion of methicillin-resistant was lower among S. aureus (84.2%), compared with CNS (90.9%).<br><br>CONCLUSION: CNS present a challenge due to their uprising resistance compared with S. aureus. The appearance of CNS-MDR strains carrying ica gene leads to treatment protocol failure on bovine farms and improper control of bovine mastitis.}, }
@article {pmid39916904, year = {2023}, author = {Bueno, MR and Dudu-Silva, G and Macedo, TT and Gomes, APAP and Rodrigues Oliveira Braga, A and Aguiar Silva, LD and Bueno-Silva, B}, title = {Lactobacillus acidophilus impairs the establishment of pathogens in a subgingival multispecies biofilm.}, journal = {Frontiers in dental medicine}, volume = {4}, number = {}, pages = {1212773}, pmid = {39916904}, issn = {2673-4915}, abstract = {The present study evaluated the antibiofilm effects of Lactobacillus acidophilus within a subgingival multispecies biofilm. Lactobacillus acidophilus (La5) at 1 × 10[2], 1 × 10[4], and 1 × 10[6] were included at the beginning of biofilm formation, which lasted 7 days. The biofilms comprised 33 periodontitis-related bacterial species and the Calgary Biofilm device was used. At the end, DNA-DNA hybridization (checkerboard) was performed. A Kruskal-Wallis test followed by a Dunn post hoc test were performed (p ≤ 0.05). La5 at 1 × 10[4] and 1 × 10[6] reduced the total counts of biofilm and the proportions of red and green complexes when compared to the control biofilm without La5 (p ≤ 0.05). La5 at 1 × 10[4] increased the proportions of Actinomyces complex compared to the controls (p ≤ 0.05). Both La5 at 1 × 10[4] and 1 × 10[6] decreased levels of 20 and 14 distinct species, respectively, including Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum polymorphum, and Parvimonas micra compared to the control (p ≤ 0.05). Only La5 at 1 × 10[4] reduced the levels of Tannerella forsythia, Fusobacterium periodonticum, and Aggregatibacter actinomycetencomytans compared to the control (p ≤ 0.05). L. acidophilus inhibited establishing periodontic pathogens from red complex such as P. gingivalis and T. forsythia in a subgingival multispecies biofilm.}, }
@article {pmid39281058, year = {2022}, author = {Moshaverinia, M and Sahmeddini, S and Lavee, F and Zareshahrabadi, Z and Zomorodian, K}, title = {Antimicrobial and Anti-Biofilm Activities of Thymus fallax Essential Oil against Oral Pathogens.}, journal = {BioMed research international}, volume = {2022}, number = {}, pages = {9744153}, pmid = {39281058}, issn = {2314-6141}, abstract = {AIM: Oral infections associated with a wide diversity of microorganisms, including bacteria and yeasts, occur frequently in humans, affecting the whole oral cavity and well-being. Oral pathogens easily grow and propagate in the oral cavity, leading to the formation of dental plaque on both soft and hard tissue. The oral cavity contains up to 700 different species of microorganisms, which Candida and Streptococci are the most common organisms. Oral diseases continue to increase despite the best efforts of the medical and scientific communities. During the past decades, drug resistance to common antibiotics used in the treatment of oral infections has been raised to high levels worldwide. To overcome such resistance, there is a growing tendency to use herbal medicine as alternative. This study was conducted to find out the chemical constitution of Thymus fallax (T. fallax) essential oil and to determine its antimicrobial and anti-biofilm efficacy against common oral pathogens.<br><br>MATERIALS AND METHODS: The chemical compositions of the essential oil distilled from T. fallax plants were analyzed using gas chromatography/mass spectrometry (GC/MS). Antimicrobial susceptibility testing against common Streptococcus, Enterococcus, Staphylococcus, and Candida strains was assessed by broth microdilution in 96-well plates as suggested by the Clinical and Laboratory Standards Institute (CLSI) methods. Biofilm growth and development were assessed using XTT reduction assay.<br><br>RESULTS: Based on the GC/MS test results, thymol (67.75%) followed by caryophyllene (E-) (7.27%) was the main component of this essential oil. T. fallax inhibited the growth of examined microbial pathogens at concentrations of 0.031-16&#x2009;&#x3bc;L/mL. Also, the essential oil showed biofilm inhibition of greater than 95% in the concentration of 8&#x2009;&#x3bc;L/mL against all tested bacterial strains as well as Candida albicans (p value < 0.05).<br><br>CONCLUSIONS: Considering the significant antimicrobial activities of T. fallax, this essential oil has the potential to be used as further antimicrobial and anti-biofilm pharmaceutical products in the control and treatment of oral infections.}, }
@article {pmid39241550, year = {2025}, author = {Guo, Z and Ge, M and Ruan, Z and Ma, Y and Chen, Y and Lin, H}, title = {2D Janus carrier-enabled trojan horse: Gallium delivery for the sequential therapy of biofilm associated infection.}, journal = {Biomaterials}, volume = {313}, number = {}, pages = {122761}, doi = {10.1016/j.biomaterials.2024.122761}, pmid = {39241550}, issn = {1878-5905}, mesh = {*Biofilms/drug effects ; Animals ; *Anti-Bacterial Agents/pharmacology/therapeutic use ; *Reactive Oxygen Species/metabolism ; *Gallium/chemistry/pharmacology ; Mice ; Drug Carriers/chemistry ; RAW 264.7 Cells ; Humans ; Staphylococcus aureus/drug effects/physiology ; }, abstract = {Biofilm-associated infections (BAIs) continue to pose a major challenge in the medical field. Nanomedicine, in particular, promises significant advances in combating BAIs through the introduction of a variety of nanomaterials and nano-antimicrobial strategies. However, studies to date have primarily focused on the removal of the bacterial biofilm and neglect the subsequent post-biofilm therapeutic measures for BAIs, rendering pure anti-biofilm strategies insufficient for the holistic recovery of affected patients. Herein, we construct an emerging dual-functional composite nanosheet (SiHx@Ga) that responds to pHs fluctuation in the biofilm microenvironment to enable a sequential therapy of BAIs. In the acidic environment of biofilm, SiHx@Ga employs the self-sensitized photothermal Trojan horse strategy to effectively impair the reactive oxygen species (ROS) defense system while triggering oxidative stress and lipid peroxidation of bacteria, engendering potent antibacterial and anti-biofilm effects. Surprisingly, in the post-treatment phase, SiHx@Ga adsorbs free pathogenic nucleic acids released after biofilm destruction, generates hydrogen with ROS-scavenging and promotes macrophage polarization to the M2 type, effectively mitigating damaging inflammatory burst and promoting tissue healing. This well-orchestrated strategy provides a sequential therapy of BAIs by utilizing microenvironmental variations, offering a conceptual paradigm shift in the field of nanomedicine anti-infectives.}, }
@article {pmid39241141, year = {2024}, author = {Yarov, YY and Tkachenko, IM and Skripnikov, PM and Hurzhii, OV and Kozak, RV}, title = {Results of microbiological study of dental biofilm in generalized periodontitis against the background of different body reactivity.}, journal = {Wiadomosci lekarskie (Warsaw, Poland : 1960)}, volume = {77}, number = {7}, pages = {1415-1419}, doi = {10.36740/WLek202407117}, pmid = {39241141}, issn = {0043-5147}, mesh = {Humans ; *Biofilms/growth &amp; development ; *Periodontitis/microbiology ; Female ; Male ; Adult ; Middle Aged ; }, abstract = {OBJECTIVE: Aim: To study the spectrum, frequency of isolation and level of colonization of dental biofilm with microorganisms in generalized periodontitis against the background of different body reactivity.<br><br>PATIENTS AND METHODS: Materials and Methods: 216 people with the diagnosis of generalized periodontitis. Depending on the state of reactivity of the organism, the patients were divided into 3 groups: with normo-, hyper- and with hyporeaction. The patients underwent patch surgery. After the surgery, dental biofilm was taken. Microbiological studies included the isolation and species identification of dental biofilm microorganisms, the results of quantitative studies of microflora: the level of colonization was expressed in colony-forming units per 1 ml (CFU/ml); the frequency of microorganisms isolation was expressed in absolute numbers. Statistical processing of the obtained digital data was performed using the computer program Statistica 8.0.<br><br>RESULTS: Results: The studies have shown that in different states of the body's reactivityi n patients with generalized periodontitis after flap surgery, different quantitative and qualitative composition of the microflora of the dental biofilm is determined. In case of normal body reactivity, there are predominantly aerobic-anaerobic associations with a wide range and quantitative predominance of aerobic microflora; in case of impaired (hyper- and hypo-) reactivity, there are predominantly aerobic-anaerobic associations with an expansion of the spectrum, frequency of isolation and level of colonization of facultative and obligate anaerobes.<br><br>CONCLUSION: Conclusions: The identified differences in the quantitative and qualitative composition of the microflora of the dental biofilm indicate the key role of the body's reactivity in the studied processes.}, }
@article {pmid39240091, year = {2024}, author = {Dramé, I and Rossez, Y and Krzewinski, F and Charbonnel, N and Ollivier-Nakusi, L and Briandet, R and Dague, E and Forestier, C and Balestrino, D}, title = {FabR, a regulator of membrane lipid homeostasis, is involved in Klebsiella pneumoniae biofilm robustness.}, journal = {mBio}, volume = {15}, number = {10}, pages = {e0131724}, pmid = {39240091}, issn = {2150-7511}, mesh = {*Bacterial Proteins/genetics/metabolism ; *Biofilms/growth &amp; development ; Fatty Acids/metabolism ; Gene Deletion ; Gene Expression Regulation, Bacterial ; Homeostasis ; *Klebsiella pneumoniae/genetics/metabolism/physiology ; Membrane Lipids/metabolism ; }, abstract = {Biofilm is a dynamic structure from which individual bacteria and micro-aggregates are released to subsequently colonize new niches by either detachment or dispersal. Screening of a transposon mutant library identified genes associated with the alteration of Klebsiella pneumoniae biofilm including fabR, which encodes a transcriptional regulator involved in membrane lipid homeostasis. An isogenic ∆fabR mutant formed more biofilm than the wild-type (WT) strain and its trans-complemented strain. The thick and round aggregates observed with ∆fabR were resistant to extensive washes, unlike those of the WT strain. Confocal microscopy and BioFlux microfluidic observations showed that fabR deletion was associated with biofilm robustness and impaired erosion over time. The genes fabB and yqfA associated with fatty acid metabolism were significantly overexpressed in the ∆fabR strain, in both planktonic and biofilm conditions. Two monounsaturated fatty acids, palmitoleic acid (C16:1) and oleic acid (C18:1), were found in higher proportion in biofilm cells than in planktonic forms, whereas heptadecenoic acid (C17:1) and octadecanoic acid, 11-methoxy (C18:0-OCH3) were found in higher proportion in the planktonic lifestyle. The fabR mutation induced variations in the fatty acid composition, with no clear differences in the amounts of saturated fatty acids (SFA) and unsaturated fatty acids for the planktonic lifestyle but lower SFA in the biofilm form. Atomic force microscopy showed that deletion of fabR is associated with decreased K. pneumoniae cell rigidity in the biofilm lifestyle, as well as a softer, more elastic biofilm with increased cell cohesion compared to the wild-type strain.IMPORTANCEKlebsiella pneumoniae is an opportunistic pathogen responsible for a wide range of nosocomial infections. The success of this pathogen is due to its high resistance to antibiotics and its ability to form biofilms. The molecular mechanisms involved in biofilm formation have been largely described but the dispersal process that releases individual and aggregate cells from mature biofilm is less well documented while it is associated with the colonization of new environments and thus new threats. Using a multidisciplinary approach, we show that modifications of bacterial membrane fatty acid composition lead to variations in the biofilm robustness, and subsequent bacterial detachment and biofilm erosion over time. These results enhance our understanding of the genetic requirements for biofilm formation in K. pneumoniae that affect the time course of biofilm development and the embrittlement step preceding its dispersal that will make it possible to control K. pneumoniae infections.}, }
@article {pmid39238019, year = {2024}, author = {Abdel-Fatah, SS and Mohammad, NH and Elshimy, R and Mosallam, FM}, title = {Impeding microbial biofilm formation and Pseudomonas aeruginosa virulence genes using biologically synthesized silver Carthamus nanoparticles.}, journal = {Microbial cell factories}, volume = {23}, number = {1}, pages = {240}, pmid = {39238019}, issn = {1475-2859}, mesh = {*Biofilms/drug effects ; *Pseudomonas aeruginosa/drug effects/genetics ; *Metal Nanoparticles/chemistry ; *Silver/pharmacology/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Microbial Sensitivity Tests ; Virulence/drug effects ; Virulence Factors/genetics/metabolism ; Plant Extracts/pharmacology/chemistry ; Bacterial Proteins/metabolism/genetics ; }, abstract = {Long-term antibiotic treatment results in the increasing resistance of bacteria to antimicrobials drugs, so it is necessary to search for effective alternatives to prevent and treat pathogens that cause diseases. This study is aimed for biological synthesis of silver Carthamus nanoparticles (Ag-Carth-NPs) to combat microbial biofilm formation and Pseudomonas aeruginosa virulence genes. Ag-Carth-NPs are synthesized using Carthamus tenuis aqueous extract as environmentally friendly method has no harmful effect on environment. General factorial design is used to optimize Ag-Carth-NPs synthesis using three variables in three levels are Carthamus extract concentration, silver nitrate concentration and gamma radiation doses. Analysis of response data indicates gamma radiation has a significant effect on Ag-Carth-NPs production. Ag-Carth-NPs have sharp peak at λ max 425 nm, small and spherical particles with size 20.0 ± 1.22 nm, high stability up to 240 day with zeta potential around - 43 ± 0.12 mV, face centered cubic crystalline structure and FT-IR spectroscopy shows peak around 620 cm[-1] that corresponding to AgNPs that stabilized by C. tenuis extract functional moiety. The antibacterial activity of Ag-Carth-NPs against pathogenic bacteria and fungi was determined using well diffusion method. The MIC values of Ag-Carth-NPs were (6.25, 6.25, 3.126, 25, 12.5, 12.5, 25 and 12.5 µg/ml), MBC values were (12.5, 12.5, 6.25, 50, 25, 25, 50 and 25 µg/ml) and biofilm inhibition% were (62.12, 68.25, 90.12, 69.51, 70.61, 71.12, 75.51 and 77.71%) against Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermidis, Candida tropicalis and Candida albicans respectively. Ag-Carth-NPs has bactericidal efficacy and significantly reduced the swarming, swimming motility, pyocyanin and protease production of P. aeruginosa. Furthermore, P. aeruginosa ToxA gene expression was significantly down regulated by 81.5%, while exoU reduced by 78.1%, where lasR gene expression reduction was 68%, while the reduction in exoU was 66% and 60.1% decrease in lasB gene expression after treatment with Ag-Carth-NPs. This activity is attributed to effect of Ag-Carth-NPs on cell membrane integrity, down regulation of virulence gene expression, and induction of general and oxidative stress in P. aeruginosa. Ag-Carth-NPs have no significant cytotoxic effects on normal human cell (Hfb4) but have IC50 at 5.6µg/mL against of HepG-2 cells. Limitations of the study include studies with low risks of silver nanoparticles for in vitro antimicrobial effects and its toxicity.}, }
@article {pmid39237859, year = {2024}, author = {Rostamani, M and Bakht, M and Rahimi, S and Alizadeh, SA and Anari, RK and Khakpour, M and Javadi, A and Fardsanei, F and Nikkhahi, F}, title = {Phenotypic and genotypic determination of resistance to common disinfectants among strains of Acinetobacter baumannii producing and non-producing biofilm isolated from Iran.}, journal = {BMC microbiology}, volume = {24}, number = {1}, pages = {323}, pmid = {39237859}, issn = {1471-2180}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Acinetobacter baumannii/drug effects/genetics/physiology/isolation &amp; purification ; *Disinfectants/pharmacology ; *Microbial Sensitivity Tests ; Humans ; Iran ; *Genotype ; *Phenotype ; Edetic Acid/pharmacology ; Drug Resistance, Bacterial/genetics ; Anti-Bacterial Agents/pharmacology ; Acinetobacter Infections/microbiology ; Sodium Hypochlorite/pharmacology ; Cross Infection/microbiology ; Chlorhexidine/pharmacology ; }, abstract = {BACKGROUND: Nosocomial infections are a global problem in hospitals all around the world. It is considered a major health problem, especially in developing countries. The increase in the patient's stay in hospitals has increased the mortality rate, and consequently, the costs drastically increase. The main purpose of using disinfectants in the hospital environment is to reduce the risk of nosocomial infections. Ethylene diamine tetra acetic acid (EDTA) causes lysis and increases susceptibility to antimicrobial agents in the planktonic form of bacteria. This substance affects the permeability of the outer membrane of bacteria. It also prevents the formation of biofilms by bacteria.<br><br>MATERIALS AND METHODS: In the current study, 120 isolates of Acinetobacter baumannii (A. baumannii) were confirmed by phenotypic and genotypic methods. Antibiogram was performed and then the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of isolates against 5% sodium hypochlorite, ethanol %70, sayasept-HP 2%, chlorhexidine 2%, dettol 4/8% were evaluated. In addition, the disinfectant effect was re-evaluated with the mixture of EDTA solution. All isolates were examined for biofilm presence by crystal violet staining method in triplicates and repeated three times for each strain. Also for all isolates detection of efflux pump genes (Qac-E, qacE-&#x394;1, SUG-E) by PCR technique was done.<br><br>RESULTS: Antibiogram results of A. baumannii showed that 6.7% were Multi-drug-resistant (MDR), and 89.2% were Extensively drug-resistant (XDR) isolates. The highest effect of disinfectants was related to 5% sodium hypochlorite, and the least effect was 70% ethanol. EDTA increases the efficacy of selected disinfectants significantly. The highest prevalence of the efflux pump genes was related to SUG-E (95%) and Qac-E (91.7%), and, the qacE-&#x394;1 gene with 12.5%. The biofilm production rate was 91.3% among all isolates.<br><br>CONCLUSION: The best and safest way to disinfect hospital floors and surfaces is to choose the right disinfectants, and learn how to use them properly. In this study, a mixture of disinfectants and EDTA had a significant effect on bactericidal activity. it was found that improper use of disinfectants, especially the use of sub-inhibitory dilutions, increases the resistance of bacteria to disinfectants.}, }
@article {pmid39237802, year = {2024}, author = {Biswas, A and A, JM and Lewis, SA and Raja, S and Paul, A and Ghosal, K and Mahmood, S and Ansari, MD}, title = {Design and Evaluation of Microemulsion-Based Drug Delivery Systems for Biofilm-Based Infection in Burns.}, journal = {AAPS PharmSciTech}, volume = {25}, number = {7}, pages = {203}, pmid = {39237802}, issn = {1530-9932}, mesh = {*Biofilms/drug effects ; *Emulsions ; *Burns/drug therapy/microbiology ; *Pseudomonas aeruginosa/drug effects ; *Drug Delivery Systems/methods ; *Anti-Bacterial Agents/administration &amp; dosage/pharmacology ; Particle Size ; Drug Liberation ; Surface-Active Agents/chemistry ; Polysorbates/chemistry ; Tea Tree Oil/administration &amp; dosage/chemistry/pharmacology ; Chemistry, Pharmaceutical/methods ; Humans ; }, abstract = {Normal skin is the first line of defense in the human body. A burn injury makes the skin susceptible to bacterial infection, thereby delaying wound healing and ultimately leading to sepsis. The chances of biofilm formation are high in burn wounds due to the presence of avascular necrotic tissue. The most common pathogen to cause burn infection and biofilm is Pseudomonas aeruginosa. The purpose of this study was to create a microemulsion (ME) formulation for topical application to treat bacterial burn infection. In the present study, tea tree oil was used as the oil phase, Tween 80 and transcutol were used as surfactants, and water served as the aqueous phase. Pseudo ternary phase diagrams were used to determine the design space. The ranges of components as suggested by the design were chosen, optimization of the microemulsion was performed, and in vitro drug release was assessed. Based on the characterization studies performed, it was found that the microemulsion were formulated properly, and the particle size obtained was within the desired microemulsion range of 10 to 300 nm. The I release study showed that the microemulsion followed an immediate release profile. The formulation was further tested based on its ability to inhibit biofilm formation and bacterial growth. The prepared microemulsion was capable of inhibiting biofilm formation.}, }
@article {pmid39236969, year = {2024}, author = {Aramli, N and Safarkar, R and Shiralipour, A and Sadeghi, Z}, title = {Biofilm formation, antibiotic-resistance and clonal relatedness among clinical isolates of Acinetobacterbaumannii.}, journal = {Microbial pathogenesis}, volume = {195}, number = {}, pages = {106916}, doi = {10.1016/j.micpath.2024.106916}, pmid = {39236969}, issn = {1096-1208}, mesh = {*Biofilms/growth &amp; development/drug effects ; Humans ; *Anti-Bacterial Agents/pharmacology ; *Acinetobacter Infections/microbiology ; *Microbial Sensitivity Tests ; Iran ; *Drug Resistance, Multiple, Bacterial/genetics ; *Acinetobacter baumannii/drug effects/genetics/isolation &amp; purification/physiology ; Molecular Typing ; Polymerase Chain Reaction ; Colistin/pharmacology ; Adult ; Hospitals ; Male ; Female ; Genotype ; Middle Aged ; }, abstract = {In this work, the antibiotic resistance, biofilm formation capability, and clonal relatedness of 50 A. baumannii isolates collected from three hospitals in Ardabil city, Iran, were evaluated. Antibiotic sensitivity and biofilm formation of isolates were determined by disk diffusion and microtiter-plate methods, respectively. Molecular typing of isolates was also performed using repetitive sequence-based PCR (REP-PCR). The majority of isolates were resistant to cephems, aminoglycosides, and carbapenems, with 80 % classified as multi-drug resistant (MDR). While, only isolates collected from blood and tracheal were resistant to colistin. Additionally, 42 isolates (84 %) had biofilm formation capability. According to rep-PCR results, 34 isolates showed similar banding patterns, while 16 isolates had unique banding patterns. Finally, based on the molecular analysis, there was a direct relationship between biofilm formation and the antibiotic resistance of isolates. In other words, MDR isolates had a higher ability to form biofilm.}, }
@article {pmid39236967, year = {2024}, author = {Haranahalli Nataraj, B and Nayakvadi, S and Dhali, A and Shome, R and Prakash, K and Revanasiddappa, ST}, title = {Evaluation of virulence determinants and cell surface properties associated with biofilm formation in methicillin-resistant Staphylococcus aureus (MRSA) and extended spectrum beta-lactamase (ESBL) Escherichia coli from livestock and poultry origin.}, journal = {Microbial pathogenesis}, volume = {195}, number = {}, pages = {106905}, doi = {10.1016/j.micpath.2024.106905}, pmid = {39236967}, issn = {1096-1208}, mesh = {*Biofilms/growth &amp; development/drug effects ; Animals ; *Escherichia coli/genetics/drug effects/pathogenicity ; *beta-Lactamases/genetics/metabolism ; *Methicillin-Resistant Staphylococcus aureus/genetics/drug effects/pathogenicity/enzymology/isolation &amp; purification ; *Poultry/microbiology ; *Virulence Factors/genetics/metabolism ; *Livestock/microbiology ; Virulence ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology ; Surface Properties ; Genotype ; Phenotype ; Staphylococcal Infections/microbiology ; }, abstract = {Antibiotic resistance poses a persistent threat to modern medicine due to the emergence of novel antibiotic-resistant strains. Therefore, a timely understanding of antibiotic resistance and the virulence biology of pathogenic bacteria, particularly those of public health significance, is crucial for implementing effective mitigation strategies. This study aimed to investigate the virulence profiles of ten S. aureus isolates (NDa to NDj) and ten E. coli isolates (ND1 to ND10) originating from livestock and poultry, and to assess how various cell surface properties and biofilm formation abilities influence antibiotic resistance phenotypes. Antibiotic resistance profiling through phenotypic (AST) and genotypic methods (PCR) confirmed that NDa to NDe were methicillin-resistant S. aureus (MRSA) and ND1 to ND5 were extended-spectrum β-lactamase (ESBL) producing E. coli isolates. Virulence properties such as hemolytic activity, coagulase activity, and nuclease activity were found to be independent of the antibiotic resistance phenotype in S. aureus. In contrast, biofilm formation phenotype was observed to influence antibiotic resistance phenotypes, with MRSA and ESBL E. coli isolates demonstrating higher biofilm formation potency. Chemical and enzymatic analysis of S. aureus and E. coli biofilms revealed proteins and polysaccharides as major components, followed by nucleic acids. Furthermore, cell surface properties such as auto-aggregation and hydrophobicity were notably higher in isolates with strong to medium biofilm-forming capabilities (ESBL and MRSA isolates), corroborated by genomic confirmation of various genes associated with biofilm, adhesion, and colonization. In conclusion, this study highlights that surface hydrophobicity and biofilm formation ability of MRSA (NDa to NDe) and ESBL E. coli (ND1 to ND5) isolates may influence antibiotic resistance phenotypes.}, }
@article {pmid39236594, year = {2024}, author = {Aniba, R and Dihmane, A and Raqraq, H and Ressmi, A and Nayme, K and Timinouni, M and Barguigua, A}, title = {Molecular and phenotypic characterization of biofilm formation and antimicrobial resistance patterns of uropathogenic staphylococcus haemolyticus isolates in Casablanca, Morocco.}, journal = {Diagnostic microbiology and infectious disease}, volume = {110}, number = {4}, pages = {116483}, doi = {10.1016/j.diagmicrobio.2024.116483}, pmid = {39236594}, issn = {1879-0070}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Staphylococcus haemolyticus/drug effects/genetics/isolation &amp; purification ; Humans ; Morocco ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; *Staphylococcal Infections/microbiology ; Drug Resistance, Multiple, Bacterial/genetics ; Female ; Male ; Phenotype ; Urinary Tract Infections/microbiology ; Adult ; Middle Aged ; Drug Resistance, Bacterial/genetics ; Young Adult ; }, abstract = {This study aimed to establish the correlation between antibiotic resistance and biofilm formation by Staphylococcus haemolyticus and to examine the impact of sub-inhibitory concentrations of antibiotics (sub-MICs) on biofilm formation. Antibiotic susceptibility testing was conducted using the disk diffusion method, and biofilm formation was determined using Congo red agar and microtiter plate methods. Antibiotic resistance and biofilm-associated genes were detected using polymerase chain reaction. The majority of the twenty-one S. haemolyticus isolates were multidrug-resistant, methicillin-resistant (MRSH) and biofilm producers, including 43 % of moderate biofilm producers. A significant correlation was observed between MRSH and MSSH isolates in terms of biofilm production. Vancomycin, gentamicin, and ciprofloxacin at their sub-MICs tended to promote biofilm formation. The eno gene was present in 76.2 % of strains, followed by aap, and atlE. This study revealed a strong correlation between the biofilm-forming ability and antibiotic resistance in S. haemolyticus, which underlines a crucial public health issue.}, }
@article {pmid39235742, year = {2025}, author = {Giaouris, E}, title = {Comparing Gene Expression Between Planktonic and Biofilm Cells of Foodborne Bacterial Pathogens Through RT-qPCR.}, journal = {Methods in molecular biology (Clifton, N.J.)}, volume = {2852}, number = {}, pages = {143-158}, pmid = {39235742}, issn = {1940-6029}, mesh = {*Plankton/genetics/growth &amp; development ; *Biofilms/growth &amp; development ; *Foodborne Diseases/microbiology ; *Bacteria/genetics/isolation &amp; purification ; *Reverse Transcriptase Polymerase Chain Reaction/methods ; *Gene Expression Regulation, Bacterial ; Data Analysis ; Reverse Transcription ; RNA, Bacterial/genetics/isolation &amp; purification ; }, abstract = {Like most microorganisms, important foodborne pathogenic bacteria, such as Salmonella enterica, Listeria monocytogenes, and several others as well, can attach to surfaces, of either abiotic or biotic nature, and create biofilms on them, provided the existence of supportive environmental conditions (e.g., permissive growth temperature, adequate humidity, and nutrient presence). Inside those sessile communities, the enclosed bacteria typically present a gene expression profile that differs from the one that would be displayed by the same cells growing planktonically in liquid media (free-swimming cells). This altered gene expression has important consequences on cellular physiology and behavior, including stress tolerance and induction of virulence. In this chapter, the methodology to use reverse transcription-quantitative polymerase chain reaction (RT-qPCR) to monitor and comparatively quantify expression changes in preselected genes of bacteria between planktonic and biofilm growth modes is presented.}, }
@article {pmid39235741, year = {2025}, author = {Dubois-Brissonnet, F}, title = {Characterization of Bacterial Membrane Fatty Acid Profiles for Biofilm Cells.}, journal = {Methods in molecular biology (Clifton, N.J.)}, volume = {2852}, number = {}, pages = {135-141}, pmid = {39235741}, issn = {1940-6029}, mesh = {*Biofilms/growth &amp; development ; *Fatty Acids/metabolism ; *Cell Membrane/metabolism ; Bacteria/metabolism ; Phospholipids/metabolism ; Membrane Fluidity ; }, abstract = {When submitted to environmental stresses, bacteria can modulate its fatty acid composition of membrane phospholipids in order to optimize membrane fluidity. Characterization of bacterial membrane fatty acid profiles is thus an interesting indicator of cellular physiological state. The methodology described here aims to improve the recovering of biofilm cells for the characterization of their fatty acid profiles. The saponification reagent is directly applied on the whole biofilm before the removal of cells from the inert surface. In this way, maximum of the cells and their fatty acids can be recovered from the deepest layers of the biofilm.}, }
@article {pmid39233097, year = {2025}, author = {Higashihira, S and Simpson, SJ and Arnold, CJ and Deckard, ER and Meneghini, RM and Greenfield, EM and Buller, LT}, title = {Biofilm Formation is Durably Prevented on Pre-Fabricated Antibiotic Cement Spacers Compared to Cobalt Chrome and Polyethylene.}, journal = {The Journal of arthroplasty}, volume = {40}, number = {3}, pages = {779-785}, doi = {10.1016/j.arth.2024.08.046}, pmid = {39233097}, issn = {1532-8406}, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/administration &amp; dosage ; *Polymethyl Methacrylate/chemistry ; *Bone Cements/chemistry ; *Staphylococcus aureus/drug effects ; *Prosthesis-Related Infections/prevention &amp; control ; *Polyethylene/chemistry ; Vancomycin ; Chromium Alloys ; Gentamicins/administration &amp; dosage/pharmacology ; Humans ; }, abstract = {BACKGROUND: A 2-stage revision remains the standard for managing chronic periprosthetic joint infection. Despite multiple spacer options, whether a particular one better resists biofilm formation remains unclear. Prefabricated polymethylmethacrylate (PMMA) articulating spacers containing antibiotics and a proprietary pore structure were developed to increase antibiotic elution characterized by a rapid burst phase for the initial one to two days and an extended slow-release phase for > 28 days. This in vitro study determined whether biofilm formation is prevented during the initial rapid burst phase and/or the slow-release phase.<br><br>METHODS: S.&#xa0;aureus-Xen36 was incubated in 1.5 mL of Luria-Bertani broth with PMMA discs with the proprietary pore structure either with or without gentamycin and vancomycin or with 'Hoffman style' positive-control discs (ultra-high molecular weight polyethylene or cobalt-chrome). Nonadherent bacteria were removed by three phosphate buffered saline rinses every 20 to 24&#xa0;hours. Planktonic bacterial growth in the culture broth and biofilm formation on the discs were measured by colony forming unit (CFU) counting and resazurin reduction assays. Experiments were repeated > four times.<br><br>RESULTS: No detectable planktonic bacterial growth or biofilm formation occurred in cultures containing PMMA with antibiotics (&#x2264; 15 CFUs/disc), whereas biofilms formed on PMMA without antibiotics, ultra-high molecular weight polyethylene, and cobalt-chrome (1&#xa0;&#xd7; 10[7] to 4&#xa0;&#xd7; 10[8] CFUs/disc, P < 0.0001). Biofilm formation was confirmed by a 100-fold decrease in sensitivity to vancomycin. To determine whether the antibiotic slow-release phase is sufficient to block biofilm formation, PMMA discs with antibiotics were preeluted for 14 days with multiple saline changes prior to bacterial inoculation. After antibiotic elution, still no detectable biofilms formed on PMMA discs with antibiotics (&#x2264; 15 CFUs/disc, P < 0.0001).<br><br>CONCLUSIONS: Antibiotic release during both the initial and slow-release phases prevented biofilm formation on PMMA with the proprietary pore structure. This may translate into improved infection eradication rates clinically.}, }
@article {pmid39226944, year = {2024}, author = {Yang, Z and Li, Z and Zhu, K and Zhou, J and Lin, H and Zhou, J}, title = {Pre-anoxic electro-stimulation enhanced simultaneous nitrification-denitrification in single-stage electrolysis-integrated sequencing batch biofilm reactor.}, journal = {Bioresource technology}, volume = {412}, number = {}, pages = {131412}, doi = {10.1016/j.biortech.2024.131412}, pmid = {39226944}, issn = {1873-2976}, mesh = {*Nitrification ; *Biofilms ; *Denitrification ; *Electrolysis ; *Bioreactors/microbiology ; *Nitrogen/metabolism ; Electricity ; Bacteria/metabolism ; }, abstract = {Simultaneous nitrification-denitrification (SND) is a promising nitrogen removal process. However, total nitrogen (TN) removal is limited due to unsatisfactory denitrification. This study demonstrated that short-time (1 h) pre-anoxic electro-stimulation significantly enhanced SND efficiency in the aerobic phase by promoting the proliferation of mixotrophic and heterotrophic denitrifiers. SND and TN removal efficiencies at the optimal electric current (EC) (0.02 A) were 85.6 % and 93.9 %, which were 39.1 % and 17.2 % higher than control. Microbial community analysis indicated that the abundance of mixotrophic and heterotrophic denitrifiers significantly increased. H2 generated in the electro-stimulation process induced the proliferation of mixotrophic denitrifiers. The weak EC (0.02 A) promoted the activity and growth of heterotrophic denitrifiers by accelerating electron transfer. They concurrently mediated heterotrophic denitrification to enhance SND efficiency. PICRUSt2 analysis revealed that the abundance of denitrifying genes dramatically surged. This study provides new insights into applying electrolysis to achieve advanced SND while minimizing electricity consumption.}, }
@article {pmid39226538, year = {2024}, author = {Özkul, G and Kehribar, E&#x15e; and Ahan, RE and Şeker, U&#xd6;&#x15e;}, title = {An Antibiotic-Degrading Engineered Biofilm Platform to Combat Environmental Antibiotic Resistance.}, journal = {ACS biomaterials science &amp; engineering}, volume = {10}, number = {10}, pages = {6625-6633}, doi = {10.1021/acsbiomaterials.4c01074}, pmid = {39226538}, issn = {2373-9878}, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology ; *Escherichia coli/genetics/metabolism/drug effects ; Ciprofloxacin/pharmacology ; Laccase/metabolism/genetics ; Drug Resistance, Microbial/genetics/drug effects ; Biodegradation, Environmental ; Escherichia coli Proteins/metabolism/genetics ; }, abstract = {The presence of antibiotics in natural water bodies is a growing problem regarding the occurrence of antibiotic resistance among various species. This is mainly caused by the excessive use of medical and veterinary antibiotics as well as the lack of effective treatment processes for eliminating residual antibiotics from wastewaters. In this study, we introduce a genetically engineered biomaterial as a solution for the effective degradation of one of the dominantly found antibiotics in natural water bodies. Our biomaterial harnesses laccase-type enzymes, which are known to attack specific types of antibiotics, i.e., fluoroquinolone-type synthetic antibiotics, and as a result degradation occurs. The engineered biomaterial is built using Escherichia coli biofilm protein CsgA as a scaffold, which is fused separately to two different laccase enzymes with the SpyTag-SpyCatcher peptide-protein duo. The designed biofilm materials were successful in degrading ciprofloxacin, as demonstrated with the data obtained from mass spectrometry analysis and cell viability assays.}, }
@article {pmid39226040, year = {2024}, author = {Dong, Q and Chang, Y and Goodwin, PH and Liu, Q and Xu, W and Xia, M and Zhang, J and Sun, R and Xu, S and Wu, C and Wu, K and Yang, L}, title = {Double-Wing Motif Protein is a Novel Biofilm Regulatory Factor of the Plant Disease Biocontrol Agent, Bacillus subtilis.}, journal = {Journal of agricultural and food chemistry}, volume = {72}, number = {37}, pages = {20273-20285}, doi = {10.1021/acs.jafc.4c02192}, pmid = {39226040}, issn = {1520-5118}, mesh = {*Bacillus subtilis/genetics/metabolism ; *Bacterial Proteins/genetics/metabolism/chemistry ; Biofilms/growth &amp; development ; *Fusarium/genetics/metabolism/physiology ; Gene Expression Regulation, Bacterial ; *Plant Diseases/microbiology ; *Triticum/microbiology ; }, abstract = {Transposon mutagenesis screening of Bacillus subtilis YB-1471, a novel rhizosphere biocontrol agent of Fusarium crown rot (FCR) of wheat, resulted in the identification of orf04391, linked to reduced biofilm formation. The gene encodes a protein possessing a putative tertiary structure of a "double-wing" DNA-binding domain. Expression of orf04391 increased during biofilm development in stationary cultures and during rapid growth in shaking cultures. An orf04391 deletion strain showed reduced biofilm production related to lower levels of the extracellular matrix, and the mutant also had reduced sporulation, adhesion, root colonization, and FCR biocontrol efficiency. Transcriptome analysis of YB-1471 and Δorf04391 in stationary culture showed that the loss of orf04391 resulted in altered expression of numerous genes, including sinI, an initiator of biofilm formation. DNA binding was shown with his-tagged Orf04391 binding to the sinIR operon in vivo and in vitro. Orf04391 appears to be a transcriptional regulator of biofilm formation in B. subtilis through the Spo0A-SinI/SinR pathway.}, }
@article {pmid39225712, year = {2024}, author = {Chekli, Y and Thiriet-Rupert, S and Caillet, C and Quilès, F and Le Cordier, H and Deshayes, E and Bardiaux, B and Pédron, T and Titecat, M and Debarbieux, L and Ghigo, JM and Francius, G and Duval, JFL and Beloin, C}, title = {Biophysical insights into sugar-dependent medium acidification promoting YfaL protein-mediated Escherichia coli self-aggregation, biofilm formation and acid stress resistance.}, journal = {Nanoscale}, volume = {16}, number = {37}, pages = {17567-17584}, doi = {10.1039/d4nr01884b}, pmid = {39225712}, issn = {2040-3372}, mesh = {Acids/chemistry ; Bacterial Adhesion/drug effects ; *Biofilms/drug effects/growth &amp; development ; *Escherichia coli/drug effects/physiology ; *Escherichia coli Proteins/metabolism/chemistry ; Hydrogen-Ion Concentration ; Stress, Physiological ; Sugars/chemistry/metabolism ; }, abstract = {The ability of bacteria to interact with their environment is crucial to form aggregates and biofilms, and develop a collective stress resistance behavior. Despite its environmental and medical importance, bacterial aggregation is poorly understood and mediated by few known adhesion structures. Here, we identified a new role for a surface-exposed Escherichia coli protein, YfaL, which can self-recognize and induce bacterial autoaggregation. This process occurs only under acidic conditions generated during E. coli growth in the presence of fermentable sugars. These findings were supported by electrokinetic and atomic force spectroscopy measurements, which revealed changes in the electrostatic, hydrophobic, and structural properties of YfaL-decorated cell surface upon sugar consumption. Furthermore, YfaL-mediated autoaggregation promotes biofilm formation and enhances E. coli resistance to acid stress. The prevalence and conservation of YfaL in environmental and clinical E. coli suggest strong evolutionary selection for its function inside or outside the host. Overall, our results emphasize the importance of environmental parameters such as low pH as physicochemical cues influencing bacterial adhesion and aggregation, affecting E. coli and potentially other bacteria's resistance to environmental stress.}, }
@article {pmid39224216, year = {2024}, author = {Gong, F and Xin, S and Liu, X and He, C and Yu, X and Pan, L and Zhang, S and Gao, H and Xu, J}, title = {Multiple biological characteristics and functions of intestinal biofilm extracellular polymers: friend or foe?.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1445630}, pmid = {39224216}, issn = {1664-302X}, abstract = {The gut microbiota is vital to human health, and their biofilms significantly impact intestinal immunity and the maintenance of microbial balance. Certain pathogens, however, can employ biofilms to elude identification by the immune system and medical therapy, resulting in intestinal diseases. The biofilm is formed by extracellular polymorphic substances (EPS), which shield microbial pathogens from the host immune system and enhance its antimicrobial resistance. Therefore, investigating the impact of extracellular polysaccharides released by pathogens that form biofilms on virulence and defence mechanisms is crucial. In this review, we provide a comprehensive overview of current pathogenic biofilm research, deal with the role of extracellular polymers in the formation and maintenance of pathogenic biofilm, and elaborate different prevention and treatment strategies to provide an innovative approach to the treatment of intestinal pathogen-based diseases.}, }
@article {pmid39222779, year = {2024}, author = {Basak, P and Dastidar, DG and Ghosh, D and Chakraborty, T and Sau, S and Chakrabarti, G}, title = {Staphylococcus aureus major cell division protein FtsZ assembly is inhibited by silibinin, a natural flavonolignan that also blocked bacterial growth and biofilm formation.}, journal = {International journal of biological macromolecules}, volume = {279}, number = {Pt 2}, pages = {135252}, doi = {10.1016/j.ijbiomac.2024.135252}, pmid = {39222779}, issn = {1879-0003}, mesh = {*Staphylococcus aureus/drug effects ; *Biofilms/drug effects ; *Bacterial Proteins/metabolism ; *Cytoskeletal Proteins/metabolism/antagonists &amp; inhibitors ; Humans ; *Silybin/pharmacology/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; HEK293 Cells ; Microbial Sensitivity Tests ; Cell Division/drug effects ; Molecular Docking Simulation ; }, abstract = {The bacterial cell division protein FtsZ has been considered a potential therapeutic target due to its rapid treadmilling that induces cellular wall construction in bacteria. The current study discovered a novel antimicrobial compound, silibinin, a natural flavonolignan and its impact on the recombinant S. aureus FtsZ (SaFtsZ). Silibinin inhibited S. aureus Newman growth in a dose-dependent manner. The IC50 and MIC values for silibinin were 75 μM and 200 μM, respectively. It had no cytotoxicity against HEK293 cells in vitro. Silibinin also enlarged the bacterial cell morphology by ∼40 folds and showed antibiofilm property. It perturbed the S. aureus membrane potential both at IC50 conc. and at MIC conc. Further, it inhibited both the polymerization and GTPase activity of SaFtsZ. It did not inhibit tubulin assembly, a eukaryotic FtsZ homolog. A fluorescence quenching study yielded the Kd value for SaFtsZ-Silibinin interaction and binding stoichiometry 0.857 ± 0.188 μM and 1:1, respectively. Both in silico study and competition assay indicated that silibinin binds at the GTP binding site on SaFtsZ. The Ki value for the silibinin-mediated inhibition of SaFtsZ was 8.8 μM. Therefore, these findings have comprehensively shown the antimicrobial behavior of silibinin on S. aureus Newman cells targeting SaFtsZ.}, }
@article {pmid39221168, year = {2024}, author = {Coenye, T and Ahonen, M and Anderson, S and Cámara, M and Chundi, P and Fields, M and Foidl, I and Gnimpieba, EZ and Griffin, K and Hinks, J and Loka, AR and Lushbough, C and MacPhee, C and Nater, N and Raval, R and Slater-Jefferies, J and Teo, P and Wilks, S and Yung, M and ,  and Webb, JS}, title = {Global challenges and microbial biofilms: Identification of priority questions in biofilm research, innovation and policy.}, journal = {Biofilm}, volume = {8}, number = {}, pages = {100210}, pmid = {39221168}, issn = {2590-2075}, abstract = {Priority question exercises are increasingly used to frame and set future research, innovation and development agendas. They can provide an important bridge between the discoveries, data and outputs generated by researchers, and the information required by policy makers and funders. Microbial biofilms present huge scientific, societal and economic opportunities and challenges. In order to identify key priorities that will help to advance the field, here we review questions from a pool submitted by the international biofilm research community and from practitioners working across industry, the environment and medicine. To avoid bias we used computational approaches to group questions and manage a voting and selection process. The outcome of the exercise is a set of 78 unique questions, categorized in six themes: (i) Biofilm control, disruption, prevention, management, treatment (13 questions); (ii) Resistance, persistence, tolerance, role of aggregation, immune interaction, relevance to infection (10 questions); (iii) Model systems, standards, regulatory, policy education, interdisciplinary approaches (15 questions); (iv) Polymicrobial, interactions, ecology, microbiome, phage (13 questions); (v) Clinical focus, chronic infection, detection, diagnostics (13 questions); and (vi) Matrix, lipids, capsule, metabolism, development, physiology, ecology, evolution environment, microbiome, community engineering (14 questions). The questions presented are intended to highlight opportunities, stimulate discussion and provide focus for researchers, funders and policy makers, informing future research, innovation and development strategy for biofilms and microbial communities.}, }
@article {pmid39219609, year = {2024}, author = {Leynaud, V and Jousserand, NP and Lucas, MN and Cavalié, L and Motta, JP and Oswald, &#xc9; and Lavoué, R}, title = {Adjunctive intravesical EDTA-tromethamine treatment of a biofilm-associated recurrent Escherichia coli cystitis in a dog.}, journal = {The Canadian veterinary journal = La revue veterinaire canadienne}, volume = {65}, number = {9}, pages = {886-893}, pmid = {39219609}, issn = {0008-5286}, mesh = {Dogs ; Animals ; *Dog Diseases/drug therapy/microbiology ; Female ; *Cystitis/veterinary/drug therapy/microbiology ; *Edetic Acid/therapeutic use/administration &amp; dosage ; *Biofilms/drug effects ; *Escherichia coli Infections/veterinary/drug therapy ; *Anti-Bacterial Agents/therapeutic use/administration &amp; dosage ; Administration, Intravesical ; Escherichia coli/drug effects ; Recurrence ; }, abstract = {A 15-month-old spayed female greater Swiss mountain dog was brought to our clinic because of relapsing episodes of urinary tract infection, present since her adoption at 2 mo of age. A diagnosis of chronic bacterial cystitis associated with an invasive, biofilm-forming uropathogenic Escherichia coli was made with bladder-wall histology and fluorescent in situ hybridization analysis. Local treatment with EDTA-tromethamine (EDTA-Tris) infusions along with parenteral cefquinome and prophylactic measures (Type-A proanthocyanidins and probiotics) coincided with clinical and bacterial remission. The dog has been free of clinical signs of urinary tract infection for >4 y. Biofilm-forming uropathogenic E. coli can cause chronic, recurrent cystitis due to low antibiotic efficacy and should be considered in cases of recurrent cystitis in dogs, especially in the absence of identified predisposing factors. This case report describes the diagnostic and therapeutic options that were used to manage a case of this type. Key clinical message: Fluorescent in situ hybridization analysis may be considered in the diagnosis of chronic bacterial cystitis in dogs, and intravesical instillations of EDTA-Tris may be helpful in managing such cases.}, }
@article {pmid39218889, year = {2024}, author = {He, W and Ma, P and Li, L and Wang, D and Li, X and Wen, X and Zuo, Y and Guo, Q and Zhang, Y and Cheng, R and Wang, Z}, title = {Efficacy and safety of preventing catheter-associated urinary tract infection by inhibiting catheter bacterial biofilm formation: a multicenter randomized controlled trial.}, journal = {Antimicrobial resistance and infection control}, volume = {13}, number = {1}, pages = {96}, pmid = {39218889}, issn = {2047-2994}, support = {31072238, 31172441, 31372562, 81170650//National Natural Science Foundation of China/ ; }, mesh = {Humans ; *Biofilms/growth &amp; development ; *Urinary Tract Infections/prevention &amp; control/microbiology ; *Catheter-Related Infections/prevention &amp; control/microbiology ; Female ; Male ; Middle Aged ; Double-Blind Method ; Urinary Catheters/adverse effects/microbiology ; Urinary Catheterization/adverse effects ; Aged ; Adult ; China ; Bandages ; Cross Infection/prevention &amp; control ; }, abstract = {BACKGROUND: Catheter-associated urinary tract infection (CAUTI) remains the most significant challenge among hospital-acquired infections (HAIs), yet still unresolved. The present study aims to evaluate the preventive effectiveness of JUC Spray Dressing (name of U.S. FDA and CE certifications, while the medical device name in China is Long-acting Antimicrobial Material) alone for CAUTI without combining with antibiotics and to evaluate the impact of bacterial biofilm formation on CAUTI results on the inserted catheters of patients.<br><br>METHODS: In this multicenter, randomized, double-blind study, we enrolled adults who suffered from acute urinary retention (AUR) and required catheterization in 6 hospitals in China. Participants were randomly allocated 1:1 according to a random number table to receive JUC Spray Dressing (JUC group) or normal saline (placebo group). The catheters were pretreated with JUC Spray Dressing or normal saline respectively before catheterization. Urine samples and catheter samples were collected after catheterization by trial staff for further investigation.<br><br>RESULTS: From April 2012 to April 2020, we enrolled 264 patients and randomly assigned them to the JUC group (n&#x2009;=&#x2009;132) and the placebo group (n&#x2009;=&#x2009;132). Clinical symptoms and urine bacterial cultures showed the incidence of CAUTI of the JUC group was significantly lower than the placebo group (P&#x2009;<&#x2009;0.01). In addition, another 30 patients were enrolled to evaluate the biofilm formation on catheters after catheter insertion in the patients' urethra (10 groups, 3 each). The results of scanning electron microscopy (SEM) showed that bacterial biofilm formed on the 5th day in the placebo group, while no bacterial biofilm formed on the 5th day in the JUC group. In addition, no adverse reactions were reported using JUC Spray Dressing.<br><br>CONCLUSION: Continued indwelling urinary catheters for 5 days resulted in bacterial biofilm formation, and pretreatment of urethral catheters with JUC Spray Dressing can prevent bacterial biofilm formation by forming a physical antimicrobial film, and significantly reduce the incidence of CAUTI. This is the first report of a study on inhibiting bacterial biofilm formation on the catheters in CAUTI patients.}, }
@article {pmid39218719, year = {2024}, author = {Rogers, ME and de Pablos, LM and Sunter, JD}, title = {Gels and cells: the Leishmania biofilm as a space and place for parasite transmission.}, journal = {Trends in parasitology}, volume = {40}, number = {10}, pages = {876-885}, doi = {10.1016/j.pt.2024.08.001}, pmid = {39218719}, issn = {1471-5007}, mesh = {*Biofilms/growth &amp; development ; *Leishmania/physiology ; Animals ; Leishmaniasis/transmission/parasitology ; Host-Parasite Interactions/physiology ; Psychodidae/parasitology/microbiology ; Protozoan Proteins/metabolism ; Humans ; }, abstract = {Leishmania make an abundant glycoprotein and proteophosphoglycan-rich gel, called the promastigote secretory gel, in the anterior midgut of their sand fly vector. This gel is a multi-faceted virulence factor which promotes the survival and transmission of the parasites between hosts. Here, we present the case that Leishmania parasites embedded in the promastigote secretory gel should be redefined as a biofilm as it shares striking similarities in biogenesis, form, and function with biofilms of other unicellular organisms. We believe that this reinterpretation will stimulate new hypotheses and avenues of research to improve our understanding of the developmental programme of Leishmania and the interaction these parasites and other kinetoplastids have with their insect hosts.}, }
@article {pmid39218374, year = {2024}, author = {Janus, A and Deepa, PM and Vergis, J and Rajasekhar, R and Habeeb, BP and Bipin, KC and Vinu David, P and Anand, L and Ratish, RL and Shyma, VH and Vijayakumar, K}, title = {Unravelling the complex mechanisms of multidrug resistance in bovine mastitis pathogens: Insights into antimicrobial resistance genes, biofilm dynamics, and efflux systems.}, journal = {Microbial pathogenesis}, volume = {195}, number = {}, pages = {106902}, doi = {10.1016/j.micpath.2024.106902}, pmid = {39218374}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; Cattle ; Animals ; *Mastitis, Bovine/microbiology ; Female ; *Drug Resistance, Multiple, Bacterial/genetics ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; *Klebsiella/genetics/drug effects ; *Staphylococcus/drug effects/genetics ; *Milk/microbiology ; Escherichia coli/genetics/drug effects ; Genes, Bacterial/genetics ; Bacterial Proteins/genetics/metabolism ; }, abstract = {Mastitis remains a paramount economic threat to dairy livestock, with antibiotic resistance severely compromising treatment efficacy. This study provides an in-depth investigation into the multidrug resistance (MDR) mechanisms in bacterial isolates from bovine mastitis, emphasizing the roles of antimicrobial resistance genes (ARGs), biofilm formation, and active efflux systems. A total of 162 Staphylococci, eight Escherichia coli, and seven Klebsiella spp. isolates were obtained from 215 milk samples of clinical and subclinical mastitis cases. Antibiotic susceptibility testing identified Twenty Staphylococci (12.35 %), six E. coli (75 %) and seven Klebsiella (100 %) identified as MDR displaying significant resistance to β-lactams and tetracyclines The Multiple Antibiotic Resistance (MAR) index of these isolates ranged from 0.375 to 1.0, highlighting extensive resistance. Notably, 29 of the 33 MDR isolates produced biofilms on Congo red agar, while all exhibited biofilm formation in the Microtitre Plate assay. Critical ARGs (blaZ, blaTEM, blaCTX-M, tetM, tetA, tetB, tetC, strA/B, aadA) and efflux pump genes (acrB, acrE, acrF, emrB, norB) regulating active efflux were identified. This pioneering study elucidates the synergistic contribution of ARGs, biofilm production, and efflux pump activity to MDR in bovine mastitis pathogens. To our knowledge, this comprehensive study is the first of its kind, offering novel insights into the complex resistance mechanisms. The findings underscore the imperative need for advanced antibiotic stewardship and strategic interventions in dairy farming to curb the rise of antibiotic-resistant infections, thereby protecting both animal and public health.}, }
@article {pmid39218364, year = {2024}, author = {Xue, Y and Cheng, Y and Wang, Q and Zhao, R and Han, X and Zhu, J and Bai, L and Li, G and Zhang, H and Liang, H}, title = {Simultaneous removal of ammonia nitrogen, sulfamethoxazole, and antibiotic resistance genes in self-corrosion microelectrolysis-enhanced counter-diffusion biofilm system.}, journal = {Bioresource technology}, volume = {412}, number = {}, pages = {131399}, doi = {10.1016/j.biortech.2024.131399}, pmid = {39218364}, issn = {1873-2976}, mesh = {*Biofilms ; *Sulfamethoxazole ; *Ammonia/metabolism ; Bioreactors ; Nitrogen ; Drug Resistance, Microbial/genetics ; Molecular Docking Simulation ; Anti-Bacterial Agents/pharmacology ; Diffusion ; Genes, Bacterial ; Water Pollutants, Chemical ; }, abstract = {A self-corrosion microelectrolysis (SME)-enhanced membrane-aerated biofilm reactor (eMABR) was developed for the removal of pollutants and reduction of antibiotic resistance genes (ARGs). Fe[2+] and Fe[3+] formed iron oxides on the biofilm, which enhanced the adsorption and redox process. SME can induce microorganisms to secrete more extracellular proteins and up-regulate the expression of ammonia monooxygenase (AMO) (0.92 log2). AMO exposed extra binding sites (ASP-69) for antibiotics, weakening the competition between NH4[+]-N and sulfamethoxazole (SMX). The NH4[+]-N removal efficiency in the S-eMABR (adding SMX and IC) increased by 44.87 % compared to the S-MABR (adding SMX). SME increased the removal performance of SMX by approximately 1.45 times, down-regulated the expressions of sul1 (-1.69 log2) and sul2 (-1.30 log2) genes, and controlled their transfer within the genus. This study provides a novel strategy for synergistic reduction of antibiotics and ARGs, and elucidates the corresponding mechanism based on metatranscriptomic and molecular docking analyses.}, }
@article {pmid39217929, year = {2024}, author = {Duan, R and Zhang, S and Jiang, S and Zhang, S and Song, Y and Luo, M and Lu, J}, title = {Glufosinate-ammonium increased nitrogen and phosphorus content in water and shaped microbial community in epiphytic biofilm of Hydrilla verticillata.}, journal = {Journal of hazardous materials}, volume = {479}, number = {}, pages = {135674}, doi = {10.1016/j.jhazmat.2024.135674}, pmid = {39217929}, issn = {1873-3336}, mesh = {*Phosphorus/analysis ; *Hydrocharitaceae/microbiology/metabolism ; *Nitrogen/analysis ; *Water Pollutants, Chemical/analysis ; *Aminobutyrates/analysis ; *Biofilms ; Microbiota ; Bacteria/metabolism/genetics/classification ; Herbicides/analysis ; Ammonium Compounds/analysis ; Wetlands ; }, abstract = {Glufosinate-ammonium (GLAM) can be released into adjacent water bodies with rainfall runoff and return water from farmland irrigation. However, impacts of GLAM on aquatic organisms remain unclear. In this study, changes in water quality, plant physiological parameters and epiphytic microbial community were investigated in wetlands with Hydrilla verticillata exposed to GLAM for 24 days. We found GLAM addition damaged cell and reduced chlorophyll a content in Hydrilla verticillata leaves, and increased ammonium and phosphorus in water (p < 0.001). The α-diversity increased in bacterial community but decreased in eukaryotic community with GLAM exposure. Neutral community models explained 62.3 % and 55.0 % of the variance in bacterial and eukaryotic communities, respectively. Many GLAM micro-biomarkers were obtained, including some clades from Proteobacteria, Bacteroidete, Actinobacteriota, Phragmoplastophyta, Annelida and Arthropoda. Redundancy analysis revealed that GLAM concentration was positively correlated to Flavobacterium, Gomphonema and Closterium but negatively to Methyloglobulus and Methylocystis. Network analysis revealed that 15 mg/L GLAM disturbed the interactions among phytoplankton, protozoa, metazoan and bacteria and reduced the stability of the microbial communities compared to 8 mg/L GLAM. GLAM shaped the nitrogen and phosphorus cycle related bacterial genes. This study highlights that herbicides are non-neglectable factors affecting the efficiency of aquatic ecological restoration in agricultural areas to control agricultural non-point source pollution.}, }
@article {pmid39216701, year = {2024}, author = {Li, Q and Zhao, W and Cui, S and Gadow, SI and Qin, Y and Li, YY}, title = {Synergetic association of hydroxyapatite-mediated biofilm and suspended sludge enhances resilience of partial nitrification/anammox (PN/A) system treating high-strength anaerobic membrane bioreactor (AnMBR) permeate.}, journal = {Bioresource technology}, volume = {412}, number = {}, pages = {131391}, doi = {10.1016/j.biortech.2024.131391}, pmid = {39216701}, issn = {1873-2976}, mesh = {*Bioreactors ; *Biofilms/drug effects ; *Durapatite/chemistry/pharmacology ; *Nitrification ; *Sewage ; Anaerobiosis ; *Membranes, Artificial ; Nitrogen ; Ammonia/metabolism ; Oxidation-Reduction ; }, abstract = {A single-stage partial nitrification/anammox (PN/A) system with biocarriers was used to treat the permeate from an anaerobic membrane reactor (AnMBR) processing organic fraction of municipal solid wastes. The suitable Ca/P ratio and high pH in the AnMBR permeate facilitated hydroxyapatite (HAP) formation, enhancing the biofilm attachment and the settleability of suspended sludge. This maintained sufficient biomass and a stable microbial structure after flushing to mitigate the free nitrous acid inhibition. Robust anammox bacteria in the biofilm and ammonia-oxidizing bacteria in the suspended sludge ensured that the PN/A system achieved an 87.3 % nitrogen removal efficiency at an influent NH4[+]-N concentration of 1802 mg/L. This study demonstrates that AnMBR permeate with high Ca, P and NH4[+]-N content is suitable for single-stage PN/A system with biocarriers due to the high resilience enhanced by HAP, offering a reference for the treatment of high-strength AnMBR permeate.}, }
@article {pmid39216664, year = {2024}, author = {Huang, Y and Hu, T and Lin, B and Ke, Y and Li, J and Ma, J}, title = {Microplastics-biofilm interactions in biofilm-based wastewater treatment processes: A review.}, journal = {Environmental pollution (Barking, Essex : 1987)}, volume = {361}, number = {}, pages = {124836}, doi = {10.1016/j.envpol.2024.124836}, pmid = {39216664}, issn = {1873-6424}, mesh = {*Biofilms/drug effects ; *Wastewater/chemistry ; *Waste Disposal, Fluid/methods ; *Microplastics/toxicity ; *Water Pollutants, Chemical ; Bioreactors ; Plastics ; }, abstract = {Microplastics, pervasive contaminants from plastic, present significant challenges to wastewater treatment processes. This review critically examines the interactions between microplastics and biofilm-based treatment technologies, specifically focusing on the concepts of "biofilm on microplastics" and "microplastics in biofilm". It discusses the implications of these interactions in contaminant removal and process performance. Advanced characterization techniques, including morphological characterization, chemical composition analysis, and bio-information analysis, are assessed to elucidate the complex interplay between microplastics and biofilms within biofilters, biological aerated filters (BAFs), rotating biological contactors (RBCs), and moving bed biofilm reactors (MBBRs). This review synthesizes current research findings, highlighting that microplastics can either hinder or enhance the treatment processes, contingent on their concentration, physicochemical properties, and the specific biofilm technology employed. The insights gained from this review are essential for developing strategies to mitigate the adverse effects of microplastics and for optimizing the design and operation of wastewater treatment.}, }
@article {pmid39216533, year = {2024}, author = {Yoshida, S and Inaba, H and Nomura, R and Nakano, K and Matsumoto-Nakano, M}, title = {Role of fimbriae variations in Porphyromonas gulae biofilm formation.}, journal = {Journal of oral biosciences}, volume = {66}, number = {4}, pages = {28-33}, doi = {10.1016/j.job.2024.08.003}, pmid = {39216533}, issn = {1880-3865}, mesh = {*Biofilms/growth &amp; development ; *Fimbriae, Bacterial/genetics/metabolism ; *Porphyromonas/genetics/physiology ; *Microscopy, Confocal ; Genotype ; Animals ; Porphyromonas gingivalis/genetics/physiology ; Fimbriae Proteins/genetics/metabolism ; }, abstract = {OBJECTIVES: Porphyromonas gulae is a major causative agent of periodontal disease in companion animals that possesses various virulence factors, including fimbriae, lipopolysaccharides, and proteases. P. gulae fimbriae are classified into three genotypes (A, B, and C) based on their nucleotide sequences. Type C fimbrial isolates have been reported to be more virulent than other fimA types, suggesting that different fimA types may aid in the regulation of periodontal pathogenesis. Detailed findings regarding the ability of P. gulae to form biofilms have yet to be reported. Here, we investigated the contributions of fimbrial genotypes in P. gulae biofilm formation.<br><br>METHODS: P. gulae and P. gingivalis biofilms were generated on plates and analyzed using confocal laser microscopy. Additionally, the biofilms formed were assessed by staining with crystal violet. Furthermore, the physical strength of P. gulae biofilms was examined by ultrasonication.<br><br>RESULTS: Biofilms formed by P. gulae type C were denser than those formed by types A and B. Moreover, the amount of biofilm formed by type C strains was significantly greater than that formed by type A and B strains, which was similar to the biofilms formed by P. gingivalis with type II fimbriae. Additionally, the physical strength of the type C biofilm was significantly greater than that of the other strains.<br><br>CONCLUSIONS: These results suggest that FimA variation may coordinate for biofilm formation. This is the first report on the observation and characterization of P. gulae biofilm formation.}, }
@article {pmid39211930, year = {2024}, author = {Paseban, K and Noroozi, S and Gharehcheloo, R and Haddadian, A and Falahi Robattorki, F and Dibah, H and Amani, R and Sabouri, F and Ghanbarzadeh, E and Hajrasouiha, S and Azari, A and Rashidian, T and Mirzaie, A and Pirdolat, Z and Salarkia, M and Shahrava, DS and Safaeinikjoo, F and Seifi, A and Sadat Hosseini, N and Saeinia, N and Bagheri Kashtali, A and Ahmadiyan, A and Mazid Abadi, R and Sadat Kermani, F and Andalibi, R and Chitgarzadeh, A and Tavana, AA and Piri Gharaghie, T}, title = {Preparation and optimization of niosome encapsulated meropenem for significant antibacterial and anti-biofilm activity against methicillin-resistant Staphylococcus aureus isolates.}, journal = {Heliyon}, volume = {10}, number = {16}, pages = {e35651}, pmid = {39211930}, issn = {2405-8440}, abstract = {BACKGROUND: One of the targeted drug delivery systems is the use of nanocarriers, and one of these drug delivery systems is niosome. Niosome have a nano-vesicular structure and are composed of non-ionic surfactants. Objective: In this study, various niosome-encapsulated meropenem formulations were prepared. Subsequently, their antibacterial and anti-biofilm activities were evaluated against methicillin-resistant Staphylococcus aureus (MRSA) strains.<br><br>METHODS: The physicochemical properties of niosomal formulations were characterized using a field scanning electron microscope, X-Ray diffraction, Zeta potential, and dynamic light scattering. Antibacterial and anti-biofilm activities were evaluated using broth microdilution and minimum biofilm inhibitory concentration, respectively. In addition, biofilm gene expression analysis was performed using quantitative Real-Time PCR. To evaluate biocompatibility, the cytotoxicity of niosome-encapsulated meropenem in a normal human diploid fibroblast (HDF) cell line was investigated using an MTT assay.<br><br>RESULTS: An F1 formulation of niosome-encapsulated meropenem with a size of 51.3&#xa0;&#xb1;&#xa0;5.84&#xa0;nm and an encapsulation efficiency of 84.86&#xa0;&#xb1;&#xa0;3.14&#xa0;% was achieved. The synthesized niosomes prevented biofilm capacity with a biofilm growth inhibition index of 69&#xa0;% and significantly downregulated icaD, FnbA, Ebps, and Bap gene expression in MRSA strains (p&#xa0;<&#xa0;0.05). In addition, the F1 formulation increased antibacterial activity by 4-6 times compared with free meropenem. Interestingly, the F1 formulation of niosome-encapsulated meropenem indicated cell viability >90&#xa0;% at all tested concentrations against normal HDF cells. The results of the present study indicate that niosome-encapsulated meropenem increased antibacterial and anti-biofilm activities without profound cytotoxicity in normal human cells, which could prove useful as a good drug delivery system.}, }
@article {pmid39214208, year = {2024}, author = {Kar, A and Saha, P and De, R and Bhattacharya, S and Mukherjee, SK and Hossain, ST}, title = {Unveiling the role of PA0730.1 sRNA in Pseudomonas aeruginosa virulence and biofilm formation: Exploring rpoS and mucA regulation.}, journal = {International journal of biological macromolecules}, volume = {279}, number = {Pt 1}, pages = {135130}, doi = {10.1016/j.ijbiomac.2024.135130}, pmid = {39214208}, issn = {1879-0003}, mesh = {*Pseudomonas aeruginosa/genetics/pathogenicity ; *Biofilms/growth &amp; development ; *Gene Expression Regulation, Bacterial ; *Sigma Factor/genetics/metabolism ; *Bacterial Proteins/genetics/metabolism ; Virulence/genetics ; *Virulence Factors/genetics ; *RNA, Small Untranslated/genetics ; }, abstract = {Small RNA (sRNA) in bacteria serve as the key messengers in regulating genes associated with quorum sensing controlled bacterial virulence. This study was aimed to unveil the regulatory role of sRNA PA0730.1 on the expression of various traits of Pseudomonas aeruginosa linked to pathogenicity, with special emphasis on the growth, colony morphology, cell motility, biofilm formation, and the expression of diverse virulence factors. PA0730.1 sRNA was found to be upregulated both during planktonic stationary growth phase and at biofilm state of P. aeruginosa PAO1. PA0730.1 deleted strain showed significant growth retardation with increased doubling time. Overexpression of PA0730.1 led to enhanced motility and biofilm formation, while the ∆PA0730.1 strain displayed significant inhibition in motility and biofilm formation. Furthermore, PA0730.1 was found to regulate the synthesis of selected virulence factors of P. aeruginosa. These observations in PA0730.1[+] and ∆PA0730.1 were found to be correlated with the PA0730.1-mediated repression of transcription regulators, mucA and rpoS, both at transcriptional and translational levels. The results suggest that PA0730.1 sRNA might be a promising target for developing new drug to counter P. aeruginosa pathogenesis, and could also help in RNA oligonucleotide based therapeutic research for formulating a novel therapeutant.}, }
@article {pmid39214178, year = {2024}, author = {Cao, Q and Zhang, C and Zhang, J and Zhang, J and Zheng, Z and Liu, H}, title = {Enhanced microbial electrosynthesis performance with 3-D algal electrodes under high CO2 sparging: Superior biofilm stability and biocathode-plankton interactions.}, journal = {Bioresource technology}, volume = {412}, number = {}, pages = {131381}, doi = {10.1016/j.biortech.2024.131381}, pmid = {39214178}, issn = {1873-2976}, mesh = {*Biofilms ; *Electrodes ; *Carbon Dioxide/metabolism ; *Plankton/metabolism ; *Bioelectric Energy Sources/microbiology ; Biomass ; Acetates/metabolism ; }, abstract = {Microbial electrosynthesis (MES) shows great promise for converting CO2 into high-value chemicals. However, cathode biofilm erosion by high CO2 sparging and the unclear role of plankton in MES hinders the continuous improvement of its performance. This study aims to enhance biofilm resistance and improve interactions between bio-cathode and plankton by upgrading waste algal biomass into 3-D porous algal electrode (PAE) with rough surface. Results showed that the acetate synthesis of PAE under 20 mL/min CO2 sparging (PAE-20) was up to 3330.61 mol/m[3], 4.63 times that of carbon felt under the same conditions (CF-20). The microbial loading of PAE-20 biofilm was twice that of CF-20. Furthermore, higher cumulative abundance of functional microorganisms was observed in plankton of PAE-20 (55 %), compared to plankton of CF-20 (14 %), and enhanced biocathode-plankton interactions significantly suppressed acetate consumption. Thus, this efficient and sustainable 3-D electrode advances MES technology and offers new perspectives for waste biomass recycling.}, }
@article {pmid39214043, year = {2024}, author = {Anoy, MMI and Hill, EA and Garcia, MR and Kim, WJ and Beliaev, AS and Beyenal, H}, title = {A directional electrode separator improves anodic biofilm current density in a well-mixed single-chamber bioelectrochemical system.}, journal = {Enzyme and microbial technology}, volume = {180}, number = {}, pages = {110502}, pmid = {39214043}, issn = {1879-0909}, support = {T32 GM008336/GM/NIGMS NIH HHS/United States ; }, mesh = {*Biofilms/growth &amp; development ; *Electrodes ; *Bioelectric Energy Sources/microbiology ; *Bioreactors/microbiology ; Hydrogen/metabolism ; Zea mays ; Equipment Design ; Electrochemical Techniques/methods ; }, abstract = {In this study, a directional electrode separator (DES) was designed and incorporated into a single-chamber bioelectrochemical system (BES) to reduce migration and reoxidation of hydrogen. This issue arises when H2, generated at the cathode, travels to the anode where anodic biofilms use H2. To test the feasibility of our design, a 3D-printed BES reactor equipped with a DES was inoculated with anaerobic digestor granules and operated under fed-batch conditions using fermented corn stover effluent. The DES equipped reactor achieved significantly higher current densities (∼53 A/m[2]) compared to a conventional single-chamber BES without a separator (∼16 A/m[2]), showing a 3.3 times improvement. Control abiotic electrochemical experiments revealed that the DES exhibited significantly higher proton conductivity (456±127 µS/mm) compared to a proton exchange membrane (67±21 µS/mm) with a statistical significance of P=0.03. The DES also effectively reduced H2 migration to the anode by 21-fold relative to the control. Overall, incorporating a DES in a single-chamber BES enhanced anodic current density by reducing H2 migration to the anode.}, }
@article {pmid39214032, year = {2024}, author = {Qu, Q and Zhang, X and Muhire, J and Yang, A and Xie, M and Xiong, R and Cheng, W and Pei, D and Huang, C}, title = {Biomimetic triggered release from hydroxyethyl cellulose @ Prussian blue microparticles for tri-modality biofilm removal.}, journal = {Colloids and surfaces. B, Biointerfaces}, volume = {244}, number = {}, pages = {114184}, doi = {10.1016/j.colsurfb.2024.114184}, pmid = {39214032}, issn = {1873-4367}, mesh = {*Cellulose/chemistry/pharmacology/analogs &amp; derivatives ; *Biofilms/drug effects ; *Ferrocyanides/chemistry/pharmacology ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Microbial Sensitivity Tests ; Particle Size ; Drug Liberation ; Biomimetic Materials/chemistry/pharmacology ; Humans ; Surface Properties ; Escherichia coli/drug effects ; Staphylococcus aureus/drug effects ; Biomimetics/methods ; Reactive Oxygen Species/metabolism ; }, abstract = {Human health is under growing threat from the increasing incidence of bacterial infections. Through their antimicrobial mechanisms, bacteria use appropriate strategies to overcome the antimicrobial effects of antibiotics. The enhanced effects of synergistic strategies on drug-resistant bacteria and biofilms have led to increasing interest in these approaches in recent years. Herein, biomimetic hydroxyethyl cellulose @ Prussian blue microparticles (HEC@PB MPs) generated by the gas-shearing method show a synergistic antibacterial property induced by antibiotic-, photothermal- and photodynamic- effect. MPs, as tri-modality antibacterial agents, exhibit ideal antibacterial activity and biofilm removal effect, and their mode of action on bacteria was investigated. Additionally, a drug release concept encouraged by the ROS-driven breakdown of cellulose, as seen in brown-rot fungi, was introduced. It combines ROS-responsive HEC and photodynamic PB and is likely to fit a niche in many applications.}, }
@article {pmid39212539, year = {2024}, author = {Goltermann, L and Shahryari, S and Rybtke, M and Tolker-Nielsen, T}, title = {Microbial Primer: The catalytic biofilm matrix.}, journal = {Microbiology (Reading, England)}, volume = {170}, number = {8}, pages = {}, pmid = {39212539}, issn = {1465-2080}, mesh = {*Biofilms/growth &amp; development ; *Bacteria/genetics/metabolism ; Extracellular Matrix/metabolism ; Bacterial Physiological Phenomena ; }, abstract = {The extracellular matrix of microbial biofilms has traditionally been viewed as a structural scaffold that retains the resident bacteria in the biofilm. Moreover, a role of the matrix in the tolerance of biofilms to antimicrobials and environmental stressors was recognized early in biofilm research. However, as research progressed it became apparent that the biofilm matrix can also be involved in processes such as bacterial migration, genetic exchange, ion capture and signalling. More recently, evidence has accumulated that the biofilm matrix can also have catalytic functions. Here we review foundational research on this fascinating catalytic role of the biofilm matrix.}, }
@article {pmid39211795, year = {2024}, author = {Liu, L and Li, H and Ma, C and Liu, J and Zhang, Y and Xu, D and Xiong, J and He, Y and Yang, H and Chen, H}, title = {Effect of anti-biofilm peptide CRAMP-34 on the biofilms of Acinetobacter lwoffii derived from dairy cows.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1406429}, pmid = {39211795}, issn = {2235-2988}, mesh = {*Biofilms/drug effects/growth &amp; development ; Animals ; Cattle ; Female ; *Acinetobacter/drug effects/genetics ; *Anti-Bacterial Agents/pharmacology ; China ; Mastitis, Bovine/microbiology/drug therapy ; Bacterial Adhesion/drug effects ; Gene Expression Profiling ; Microbial Sensitivity Tests ; Acinetobacter Infections/microbiology ; }, abstract = {Dairy mastitis is one of the most common diseases in dairy farming, and the formation of pathogenic bacteria biofilms may be an important reason why traditional antibiotic therapy fails to resolve some cases of dairy mastitis. We isolated and identified three strains of A. lwoffii were with strong biofilm forming ability from dairy cow mastitis samples from Chongqing dairy farms in China. In order to investigate the effect of novel anti-biofilm peptide CRAMP-34 on A.lwoffii biofilms, the anti-biofilm effect was evaluated by crystal violet staining, biofilms viable bacteria counting and confocal laser scanning microscopy (CLSM). In addition, transcriptome sequencing analysis, qRT-PCR and phenotypic verification were used to explore the mechanism of its action. The results showed that CRAMP-34 had a dose-dependent eradicating effect on A. lwoffii biofilms. Transcriptome sequencing analysis showed that 36 differentially expressed genes (11 up-regulated and 25 down-regulated) were detected after the intervention with the sub-inhibitory concentration of CRAMP-34. These differentially expressed genes may be related to enzyme synthesis, fimbriae, iron uptake system, capsular polysaccharide and other virulence factors through the functional analysis of differential genes. The results of subsequent bacterial motility and adhesion tests showed that the motility of A.lwoffii were enhanced after the intervention of CRAMP-34, but there was no significant change in adhesion. It was speculated that CRAMP-34 may promote the dispersion of biofilm bacteria by enhancing the motility of biofilm bacteria, thereby achieving the effect of eradicating biofilms. Therefore, these results, along with our other previous findings, suggest that CRAMP-34 holds promise as a new biofilm eradicator and deserves further research and development.}, }
@article {pmid39210732, year = {2024}, author = {Mourão, A and Serrano, I and Cunha, E and Tavares, L and Lourenço, A and Oliveira, M}, title = {In vitro efficacy of lavender oil, otological gel and gentamicin to eradicate biofilm produced by Pseudomonas aeruginosa.}, journal = {Veterinary dermatology}, volume = {35}, number = {6}, pages = {726-735}, doi = {10.1111/vde.13294}, pmid = {39210732}, issn = {1365-3164}, support = {UIDB/00276/2020//Funda&#xe7;&#xe3;o para a Ci&#xea;ncia e a Tecnologia/ ; LA/P/0059/2020//Funda&#xe7;&#xe3;o para a Ci&#xea;ncia e a Tecnologia/ ; }, mesh = {*Biofilms/drug effects ; *Pseudomonas aeruginosa/drug effects ; *Gentamicins/pharmacology/administration &amp; dosage ; Animals ; *Lavandula ; *Oils, Volatile/pharmacology/administration &amp; dosage ; Dogs ; *Plant Oils/pharmacology/administration &amp; dosage ; *Anti-Bacterial Agents/pharmacology ; *Otitis Externa/veterinary/drug therapy/microbiology ; Dog Diseases/drug therapy/microbiology ; Pseudomonas Infections/veterinary/drug therapy ; Gels ; Microbial Sensitivity Tests ; }, abstract = {BACKGROUND: Otitis externa (OE) is one of the most frequently diagnosed dermatological diseases in dogs, having a multifactorial aetiology. Among the bacterial agents associated with canine OE, Pseudomonas aeruginosa is of special concern owing to its frequent multidrug resistance profile and ability to form biofilms related to the infection's chronicity and recurrence.<br><br>OBJECTIVES: The main objective of this study was to evaluate and compare the antibiofilm activity of two innovative antimicrobials-an otological gel containing a synthetic antimicrobial peptide and Lavandula angustifolia essential oil-with gentamicin (a conventional antibiotic) using biofilm-producing P. aeruginosa isolates obtained from dogs with OE.<br><br>MATERIALS AND METHODS: The biofilm eradication capacity of gentamicin, otological gel and lavender oil was determined against a collection of 12 P.&#x2009;aeruginosa biofilm-producers among 35 clinical isolates obtained from the ear canals of dogs with OE. Also, the antimicrobial activity of the otological gel against P.&#x2009;aeruginosa biofilms was assessed in an in&#xa0;vitro model of dog cerumen.<br><br>RESULTS: Lavender oil showed the best effectiveness after 30&#x2009;min of contact, eradicating 58.3% (seven of 12) of the isolates, and gentamicin showed full eradication (12 of 12) after 24&#x2009;h. The otological gel acted more slowly than the lavender oil; yet at 24&#x2009;h, the antibiofilm capacity of both compounds was similar, with no significant difference between them. It also was found that triglycerides from synthetic cerumen earwax had antipseudomonal activity and, when combined with the otological gel, led to the full eradication of P.&#x2009;aeruginosa.<br><br>The results of this in&#xa0;vitro study indicate that lavender oil and the otological gel may be effective topical treatments for canine OE promoted by P.&#x2009;aeruginosa biofilm-producers, as alternatives to gentamicin.}, }
@article {pmid39210155, year = {2024}, author = {Ashraf, N and Anas, A and Sukumaran, V and James, J and Bilutheth, MN and Chekkillam, AR and Jasmin, C and Raj K, D and Babu, I}, title = {Biofilm-forming bacteria associated with corals secrete melanin with UV-absorption properties.}, journal = {World journal of microbiology &amp; biotechnology}, volume = {40}, number = {10}, pages = {313}, pmid = {39210155}, issn = {1573-0972}, support = {MLP2013//Council of Scientific and Industrial Research, India/ ; BT/PR30688/BIC/101/1139/2018//Department of Biotechnology, Ministry of Science and Technology, India/ ; }, mesh = {*Anthozoa/microbiology ; Animals ; *Melanins/metabolism ; *Bacteria/classification/metabolism/isolation &amp; purification/genetics ; *Biofilms/growth &amp; development ; India ; Ultraviolet Rays ; RNA, Ribosomal, 16S/genetics ; Coral Reefs ; Phylogeny ; Microbiota ; }, abstract = {Corals are colonized by a plethora of microorganisms, and their diversity plays a significant role in the health and resilience of corals when they face oxidative stress leading to bleaching. In the current study, we examined 238 bacteria isolated from five different coral species (Acropora hyacinthus, Pocillopora damicornis, Podabacea crustacea, Porites lobata, and Pavona venosa) collected from the coral reef ecosystems of Kavaratti, Lakshadweep Islands, India. We found that bacteria such as Psychrobacter sp., Halomonas sp., Kushneria sp., Staphylococcus sp., Bacillus sp., Brachybacterium sp., Citrobacter sp., and Salinicola sp. were commonly present in the corals. On the other hand, Qipengyuania sp., Faucicola sp., Marihabitans sp., Azomonas sp., Atlantibacter sp., Cedecea sp., Krasalinikoviella sp., and Aidingimonas sp. were not previously reported from the corals. Among the bacterial isolates, a significant number showed high levels of biofilm formation (118), UV absorption (119), and melanin production (127). Considering these properties, we have identified a combination of seven bacteria from the genera Halomonas sp., Psychrobacter sp., Krasalinikoviella sp., and Micrococcus sp. as a potential probiotic consortium for protecting corals from oxidative stress. Overall, this study provides valuable insights into the coral microbiome and opens up possibilities for microbiome-based interventions to protect these crucial ecosystems in the face of global environmental challenges.}, }
@article {pmid39209232, year = {2024}, author = {Dorner, M and Behrens, S}, title = {Biochar as ammonia exchange biofilm carrier for enhanced aerobic nitrification in activated sludge.}, journal = {Bioresource technology}, volume = {413}, number = {}, pages = {131374}, doi = {10.1016/j.biortech.2024.131374}, pmid = {39209232}, issn = {1873-2976}, mesh = {*Charcoal/chemistry ; *Sewage/microbiology ; *Biofilms ; *Nitrification ; *Ammonia/metabolism ; Aerobiosis ; Hydrogen-Ion Concentration ; Bioreactors ; }, abstract = {The effects of biochar on aerobic nitrification in activated sludge were investigated in sequencing batch reactors. Biochar amended reactors exhibited 87-94 % lower ammonia in effluent and 16-71 % greater removal of total Kjeldahl nitrogen compared to control reactors. Quantitative qPCR analyses revealed that the relative abundance of ammonia oxidizing bacteria (AOB, amoA/16S rRNA genes) was greater in biochar than in control reactors. AOB were enriched on biochar surfaces, with biochar particles having up to 12.1 times greater relative abundance of AOB compared to suspended biomass. Biochar's maximum ammonia sorption capacity of 4.4 mg N/g at pH 7 decreased with decreasing pH, however a pH-sensitive fluorescent probe was used to show that biofilms growing on biochar surfaces maintain a median pH of > 6.7 despite reactor acidification by nitrification. Microbial colonization of biochar in activated sludge creates a pH-sheltered environment that sustains biochar's ammonia sorption capacity, resulting in enrichment of AOB on biochar particles and improved nitrification.}, }
@article {pmid39208563, year = {2024}, author = {Guo, Q and Liu, B and Guo, X and Yan, P and Cao, B and Liu, R and Liu, X}, title = {Characterization and application of LysSGF2 and HolSGF2 as potential biocontrol agents against planktonic and biofilm cells of common pathogenic bacteria.}, journal = {International journal of food microbiology}, volume = {425}, number = {}, pages = {110848}, doi = {10.1016/j.ijfoodmicro.2024.110848}, pmid = {39208563}, issn = {1879-3460}, mesh = {*Biofilms/drug effects ; Bacteriophages ; Anti-Bacterial Agents/pharmacology ; Plankton/drug effects ; Shigella flexneri/drug effects ; Muramidase/pharmacology ; Gram-Negative Bacteria/drug effects ; Gram-Positive Bacteria/drug effects ; Animals ; }, abstract = {Antimicrobial resistance represents a global health emergency, necessitating the introduction of novel antimicrobial agents. In the present study, lysozyme and holin from Shigella flexneri 1.1868 phage SGF2, named LysSGF2 and HolSGF2, respectively, were cloned, expressed, and characterized. LysSGF2 and HolSGF2 showed lytic activities against S. flexneri 1.1868 cells at 4-55 °C and pH 3.1-10.3. LysSGF2 exhibited antimicrobial activity against five gram-negative and two gram-positive bacteria. HolSGF2 showed antimicrobial activity against four gram-negative and one gram-positive species. The antibacterial activities of LysSGF2 and HolSGF2 were determined in liquid beverages, including bottled water and milk. The relative lytic activity of LysSGF2 combined with HolSGF2 against the tested bacteria was approximately 46-77 % in water. Furthermore, the combination markedly decreased the viable counts of tested bacteria by approximately 3-5 log CFU/mL. LysSGF2 and HolSGF2 could efficiently remove biofilms on polystyrene, glass, and stainless-steel. The efficacy of the LysSGF2 and HolSGF2 combination against the tested bacteria on polystyrene was 58-71 %. Combination treatment effectively killed biofilm cells formed on stainless-steel and glass by 1-4 log CFU/mL. ese results indicate that LysSGF2 and HolSGF2 can successfully control both the planktonic and biofilm cells of common pathogenic bacteria, suggesting that the combined or single use of LysSGF2 and HolSGF2 may be of great value in food processing.}, }
@article {pmid39207160, year = {2024}, author = {Shen, L and Zhang, J and Chen, Y and Rao, L and Wang, X and Zhao, H and Wang, B and Xiao, Y and Yu, J and Xu, Y and Shi, J and Han, W and Song, Z and Yu, F}, title = {Correction for Shen et al., "Small-Molecule Compound CY-158-11 Inhibits Staphylococcus aureus Biofilm Formation".}, journal = {Microbiology spectrum}, volume = {12}, number = {10}, pages = {e0198424}, doi = {10.1128/spectrum.01984-24}, pmid = {39207160}, issn = {2165-0497}, }
@article {pmid39205249, year = {2024}, author = {Soro, O and Kigen, C and Nyerere, A and Gachoya, M and Georges, M and Odoyo, E and Musila, L}, title = {Characterization and Anti-Biofilm Activity of Lytic Enterococcus Phage vB_Efs8_KEN04 against Clinical Isolates of Multidrug-Resistant Enterococcus faecalis in Kenya.}, journal = {Viruses}, volume = {16}, number = {8}, pages = {}, pmid = {39205249}, issn = {1999-4915}, support = {PAU/ADM/PAUSTI/9/2022//African Union Commission/ ; JKU/ADM/10B//AFRICA-ai-JAPAN Project Innovation Research Funds/ ; }, mesh = {*Biofilms/growth &amp; development/drug effects ; *Enterococcus faecalis/virology/drug effects ; Kenya ; *Bacteriophages/physiology/genetics/isolation &amp; purification/classification ; *Drug Resistance, Multiple, Bacterial ; *Genome, Viral ; *Host Specificity ; Humans ; Anti-Bacterial Agents/pharmacology ; Gram-Positive Bacterial Infections/microbiology ; Sewage/virology ; }, abstract = {Enterococcus faecalis (E. faecalis) is a growing cause of nosocomial and antibiotic-resistant infections. Treating drug-resistant E. faecalis requires novel approaches. The use of bacteriophages (phages) against multidrug-resistant (MDR) bacteria has recently garnered global attention. Biofilms play a vital role in E. faecalis pathogenesis as they enhance antibiotic resistance. Phages eliminate biofilms by producing lytic enzymes, including depolymerases. In this study, Enterococcus phage vB_Efs8_KEN04, isolated from a sewage treatment plant in Nairobi, Kenya, was tested against clinical strains of MDR E. faecalis. This phage had a broad host range against 100% (26/26) of MDR E. faecalis clinical isolates and cross-species activity against Enterococcus faecium. It was able to withstand acidic and alkaline conditions, from pH 3 to 11, as well as temperatures between -80 °C and 37 °C. It could inhibit and disrupt the biofilms of MDR E. faecalis. Its linear double-stranded DNA genome of 142,402 bp contains 238 coding sequences with a G + C content and coding gene density of 36.01% and 91.46%, respectively. Genomic analyses showed that phage vB_Efs8_KEN04 belongs to the genus Kochikohdavirus in the family Herelleviridae. It lacked antimicrobial resistance, virulence, and lysogeny genes, and its stability, broad host range, and cross-species lysis indicate strong potential for the treatment of Enterococcus infections.}, }
@article {pmid39204439, year = {2024}, author = {Apaza Ticona, L and Martínez Noguerón, A and Sánchez Sánchez-Corral, J and Montoto Lozano, N and Ortega Domenech, M}, title = {Anti-Inflammatory, Antibacterial, Anti-Biofilm, and Anti-Quorum Sensing Activities of the Diterpenes Isolated from Clinopodium bolivianum.}, journal = {Pharmaceutics}, volume = {16}, number = {8}, pages = {}, pmid = {39204439}, issn = {1999-4923}, abstract = {This study reports for the first time the isolation of four diterpenoid compounds: 15-Hydroxy-12-oxo-abietic acid (1), 12α-hydroxyabietic acid (2), (-)-Jolkinolide E (3), and 15-Hydroxydehydroabietic acid (4) from Clinopodium bolivianum (C. bolivianum). The findings demonstrate that both the dichloromethane/methanol (DCMECB) extract of C. bolivianum and the isolated compounds exhibit significant anti-inflammatory (inhibition of NF-κB activation), antibacterial (primarily against Gram-positive bacteria), and anti-biofilm (primarily against Gram-negative bacteria) activities. Among the isolated diterpenes, compounds 3 and 4 showed notable anti-inflammatory effects, with IC50 values of 17.98 μM and 23.96 μM for compound 3, and 10.79 μM and 17.37 μM for compound 4, in the HBEC3-KT and MRC-5 cell lines. Regarding their antibacterial activity, compounds 3 and 4 were particularly effective, with MIC values of 0.53-1.09 μM and 2.06-4.06 μM, respectively, against the S. pneumoniae and S. aureus Gram-positive bacteria. Additionally, these compounds demonstrated significant anti-biofilm and anti-quorum sensing activities, especially against Gram-negative bacteria (H. influenzae and L. pneumophila). We also explain how compound 3 (BIC = 1.50-2.07 μM, Anti-QS = 0.31-0.64 μM) interferes with quorum sensing due to its structural homology with AHLs, while compound 4 (BIC = 4.65-7.15 μM, Anti-QS = 1.21-2.39 μM) destabilises bacterial membranes due to the presence and position of its hydroxyl groups. These results support the traditional use of C. bolivianum against respiratory infections caused by both Gram-positive and Gram-negative bacteria. Furthermore, given the increasing antibiotic resistance and biofilm formation by these bacteria, there is a pressing need for the development of new, more active compounds. In this context, compounds 3 and 4 isolated from C. bolivianum offer promising potential for the development of a library of new, more potent, and selective drugs.}, }
@article {pmid39204321, year = {2024}, author = {MubarakAli, D and Saravanakumar, K and Ganeshalingam, A and Santosh, SS and De Silva, S and Park, JU and Lee, CM and Cho, SH and Kim, SR and Cho, N and Thiripuranathar, G and Park, S}, title = {Recent Progress in Multifunctional Stimuli-Responsive Combinational Drug Delivery Systems for the Treatment of Biofilm-Forming Bacterial Infections.}, journal = {Pharmaceutics}, volume = {16}, number = {8}, pages = {}, pmid = {39204321}, issn = {1999-4923}, support = {2022R1I1A1A01067464//National Research Foundation (NRF) of Korea/ ; NRF-2022R1F1A1063364//Ministry of Education, Science, and Technology, Republic of Korea/ ; K413000//Korea Basic Science Institute/ ; G22202201282201//Korea Institute of Marine Science &amp; Technology Promotion (KIMST), funded by the Ministry of Oceans and Fisheries/ ; }, abstract = {Drug-resistant infectious diseases pose a substantial challenge and threat to medical regimens. While adaptive laboratory evolution provides foresight for encountering such situations, it has inherent limitations. Novel drug delivery systems (DDSs) have garnered attention for overcoming these hurdles. Multi-stimuli responsive DDSs are particularly effective due to their reduced background leakage and targeted drug delivery to specific host sites for pathogen elimination. Bacterial infections create an acidic state in the microenvironment (pH: 5.0-5.5), which differs from normal physiological conditions (pH: 7.4). Infected areas are characterized by the overexpression of hyaluronidase, gelatinase, phospholipase, and other virulence factors. Consequently, several effective stimuli-responsive DDSs have been developed to target bacterial pathogens. Additionally, biofilms, structured communities of bacteria encased in a self-produced polymeric matrix, pose a significant challenge by conferring resistance to conventional antimicrobial treatments. Recent advancements in nano-drug delivery systems (nDDSs) show promise in enhancing antimicrobial efficacy by improving drug absorption and targeting within the biofilm matrix. nDDSs can deliver antimicrobials directly to the biofilm, facilitating more effective eradication of these resilient bacterial communities. Herein, this review examines challenges in DDS development, focusing on enhancing antibacterial activity and eradicating biofilms without adverse effects. Furthermore, advances in immune system modulation and photothermal therapy are discussed as future directions for the treatment of bacterial diseases.}, }
@article {pmid39203688, year = {2024}, author = {Seručnik, M and Dogsa, I and Zadravec, LJ and Mandic-Mulec, I and Žnidaršič-Plazl, P}, title = {Development of a Microbioreactor for Bacillus subtilis Biofilm Cultivation.}, journal = {Micromachines}, volume = {15}, number = {8}, pages = {}, pmid = {39203688}, issn = {2072-666X}, abstract = {To improve our understanding of Bacillus subtilis growth and biofilm formation under different environmental conditions, two versions of a microfluidic reactor with two channels separated by a polydimethylsiloxane (PDMS) membrane were developed. The gas phase was introduced into the channel above the membrane, and oxygen transfer from the gas phase through the membrane was assessed by measuring the dissolved oxygen concentration in the liquid phase using a miniaturized optical sensor and oxygen-sensitive nanoparticles. B. subtilis biofilm formation was monitored in the growth channels of the microbioreactors, which were designed in two shapes: one with circular extensions and one without. The volumes of these microbioreactors were (17 ± 4) μL for the reactors without extensions and (28 ± 4) μL for those with extensions. The effect of microbioreactor geometry and aeration on B. subtilis biofilm growth was evaluated by digital image analysis. In both microbioreactor geometries, stable B. subtilis biofilm formation was achieved after 72 h of incubation at a growth medium flow rate of 1 μL/min. The amount of oxygen significantly influenced biofilm formation. When the culture was cultivated with a continuous air supply, biofilm surface coverage and biomass concentration were higher than in cultivations without aeration or with a 100% oxygen supply. The channel geometry with circular extensions did not lead to a higher total biomass in the microbioreactor compared to the geometry without extensions.}, }
@article {pmid39203579, year = {2024}, author = {Wint, WY and Miyanohara, M and Terada-Ito, C and Yamada, H and Ryo, K and Murata, T}, title = {Effects of Sucrose and Farnesol on Biofilm Formation by Streptococcus mutans and Candida albicans.}, journal = {Microorganisms}, volume = {12}, number = {8}, pages = {}, pmid = {39203579}, issn = {2076-2607}, abstract = {Candida albicans (C. albicans) and Streptococcus mutans (S. mutans) are frequently detected in the plaque biofilms of children with early childhood caries. This study investigated the effects of sucrose and farnesol on biofilm formation by the oral pathogens S. mutans and C. albicans, including their synergistic interactions. Biofilm formation dynamics were monitored using the Cell Index (CI). The CI for S. mutans increased in the brain-heart infusion medium, peaking at 10 h; however, the addition of sucrose reduced the CI. For C. albicans yeast cells, the CI increased at sucrose concentrations > 0.5%, peaking at 2 h. Mixed cultures of S. mutans and C. albicans yeast cells showed significantly higher CI values in the presence of sucrose, suggesting a synergistic effect on biofilm formation. Farnesol consistently suppressed biofilm formation by C. albicans yeast cells, even in the presence of sucrose, and higher farnesol concentrations resulted in greater inhibition. Regarding C. albicans hyphal cells, sucrose did not enhance biofilm formation, whereas farnesol significantly reduced biofilm formation at all concentrations tested. These findings elucidate the complex roles of sucrose and farnesol in biofilm formation by S. mutans and C. albicans and emphasize the potential of farnesol as an effective oral biofilm inhibitor.}, }
@article {pmid39203542, year = {2024}, author = {Wang, X and Wu, Y and Chen, M and Fu, C and Xu, H and Li, L}, title = {Different Roles of Dioxin-Catabolic Plasmids in Growth, Biofilm Formation, and Metabolism of Rhodococcus sp. Strain p52.}, journal = {Microorganisms}, volume = {12}, number = {8}, pages = {}, pmid = {39203542}, issn = {2076-2607}, support = {22076102//National Natural Science Foundation of China/ ; 21876100//National Natural Science Foundation of China/ ; 2023KJ005//Youth Innovation Team Project of Higher School in Shandong Province/ ; }, abstract = {Microorganisms harbor catabolic plasmids to tackle refractory organic pollutants, which is crucial for bioremediation and ecosystem health. Understanding the impacts of plasmids on hosts provides insights into the behavior and adaptation of degrading bacteria in the environment. Here, we examined alterations in the physiological properties and gene expression profiles of Rhodococcus sp. strain p52 after losing two conjugative dioxin-catabolic megaplasmids (pDF01 and pDF02). The growth of strain p52 accelerated after pDF01 loss, while it decelerated after pDF02 loss. During dibenzofuran degradation, the expression levels of dibenzofuran catabolic genes on pDF01 were higher compared to those on pDF02; accordingly, pDF01 loss markedly slowed dibenzofuran degradation. It was suggested that pDF01 is more beneficial to strain p52 under dibenzofuran exposure. Moreover, plasmid loss decreased biofilm formation, especially after pDF02 loss. Transcriptome profiling revealed different pathways enriched in upregulated and downregulated genes after pDF01 and pDF02 loss, indicating different adaptation mechanisms. Based on the transcriptional activity variation, pDF01 played roles in transcription and anabolic processes, while pDF02 profoundly influenced energy production and cellular defense. This study enhances our knowledge of the impacts of degradative plasmids on native hosts and the adaptation mechanisms of hosts, contributing to the application of plasmid-mediated bioremediation in contaminated environments.}, }
@article {pmid39203493, year = {2024}, author = {Saoudi, B and Bariz, K and Saci, S and Belounis, Y and Ait Issad, H and Abbaci, M and Mustapha, MA and Nabti, EH and Alenazy, R and Alhussaini, MS and Alyahya, AAI and Alqasmi, M and Alhumaidi, MS and Almufarriji, FM and Houali, K}, title = {Enhancing Antibiotic Efficacy and Combating Biofilm Formation: Evaluating the Synergistic Potential of Origanum vulgare Essential Oil against Multidrug-Resistant Gram-Negative Bacteria.}, journal = {Microorganisms}, volume = {12}, number = {8}, pages = {}, pmid = {39203493}, issn = {2076-2607}, abstract = {Multidrug-resistant (MDR) Gram-negative bacteria remain a global public health issue due to the barrier imposed by their outer membrane and their propensity to form biofilms. It is becoming imperative to develop new antibacterial strategies. In this context, this study aims to evaluate the antibacterial efficacy of Origanum vulgare essential oil (OEO), alone and in combination with antibiotics, as well as its antibiofilm action against multidrug-resistant Gram-negative strains. OEO components were identified by gas chromatography-mass spectrometry (GC-MS), and antibacterial activity was assessed using the agar diffusion test and the microdilution method. Interactions between OEO and antibiotics were examined using the checkerboard method, while antibiofilm activity was analyzed using the crystal violet assay. Chemical analysis revealed that carvacrol was the major compound in OEO (61.51%). This essential oil demonstrated activity against all the tested strains, with inhibition zone diameters (IZDs) reaching 32.3 ± 1.5 mm. The combination of OEO with different antibiotics produced synergistic and additive effects, leading to a reduction of up to 98.44% in minimum inhibitory concentrations (MICs). In addition, this essential oil demonstrated an ability to inhibit and even eradicate biofilm formation. These results suggest that OEO could be exploited in the development of new molecules, combining its metabolites with antibiotics.}, }
@article {pmid39203430, year = {2024}, author = {Gilmore, A and Badham, M and Rudisin, W and Ashton, N and Williams, D}, title = {A Bead Biofilm Reactor for High-Throughput Growth and Translational Applications.}, journal = {Microorganisms}, volume = {12}, number = {8}, pages = {}, pmid = {39203430}, issn = {2076-2607}, support = {W81XWH-20-1-0378//Congressionally Directed Medical Research Programs/ ; }, abstract = {Bacteria in natural ecosystems such as soil, dirt, or debris preferentially reside in the biofilm phenotype. When a traumatic injury, such as an open fracture, occurs, these naturally dwelling biofilms and accompanying foreign material can contaminate the injury site. Given their high tolerance of systemic levels of antibiotics that may be administered prophylactically, biofilms may contribute to difficult-to-treat infections. In most animal models, planktonic bacteria are used as initial inocula to cause infection, and this might not accurately mimic clinically relevant contamination and infection scenarios. Further, few approaches and systems utilize the same biofilm and accompanying substrate throughout the experimental continuum. In this study, we designed a unique reactor to grow bacterial biofilms on up to 50 silica beads that modeled environmental wound contaminants. The data obtained indicated that the reactor system repeatably produced mature Staphylococcus aureus and Pseudomonas aeruginosa biofilms on the silica beads, with an average of 5.53 and 6.21 log10 colony-forming units per mm[2], respectively. The bead substrates are easily manipulable for in vitro or in vivo applications, thus improving translatability. Taken together, the bead biofilm reactor presented herein may be a useful system for repeatably growing established biofilms on silica beads that could be used for susceptibility testing and as initial inocula in future animal models of trauma-related injuries.}, }
@article {pmid39203407, year = {2024}, author = {Li, X and Ding, W and Li, Z and Yan, Y and Tong, Y and Xu, J and Li, M}, title = {vB_CacS-HV1 as a Novel Pahexavirus Bacteriophage with Lytic and Anti-Biofilm Potential against Cutibacterium acnes.}, journal = {Microorganisms}, volume = {12}, number = {8}, pages = {}, pmid = {39203407}, issn = {2076-2607}, support = {2022-KF-08//Open Project of the State Key Laboratory of Plateau Ecology and Agriculture/ ; 2022-NK-107//National Science and Technology Achievement Transformation Special Project - Pre-subsidy - Rural Affairs Department/ ; }, abstract = {Acne vulgaris is a prevalent chronic inflammatory skin disease, most common in adolescence and often persisting into adulthood, leading to severe physical and psychological impacts. The primary etiological factor is Cutibacterium acnes infection. The overuse of antibiotics for acne treatment over recent decades has led to the emergence of antibiotic-resistant Cutibacterium acnes strains. In this study, we isolated and characterized a novel bacteriophage, vB_CacS-HV1, from saliva samples. The average nucleotide identity analysis indicated that vB_CacS-HV1 is a new species within the Pahexavirus genus, enhancing our understanding of this underexplored group. vB_CacS-HV1 demonstrates favorable stability, lacks potentially harmful genetic elements (virulence factors, antibiotic resistance genes, transposons, and integrases), and exhibits potent lytic and anti-biofilm activities against Cutibacterium acnes at low concentrations. These advantages highlight vB_CacS-HV1's potential as a promising antibacterial agent that could possibly be complementary to antibiotics or other treatments for acne therapy.}, }
@article {pmid39203365, year = {2024}, author = {Principi, N and Esposito, S}, title = {Biofilm Production and Its Implications in Pediatrics.}, journal = {Microorganisms}, volume = {12}, number = {8}, pages = {}, pmid = {39203365}, issn = {2076-2607}, abstract = {Biofilms, aggregates of bacteria enclosed in a self-produced matrix, have been implicated in various pediatric respiratory infections, including acute otitis media (AOM), otitis media with effusion (OME), adenoiditis, protracted bacterial bronchitis, and pulmonary exacerbations in cystic fibrosis. These infections are prevalent in children and often associated with biofilm-producing pathogens, leading to recurrent and chronic conditions. Biofilms reduce antibiotic efficacy, contributing to treatment failure and disease persistence. This narrative review discusses biofilm production by respiratory pathogens such as Streptococcus pneumoniae, non-typeable Haemophilus influenzae, Pseudomonas aeruginosa, and Staphylococcus aureus. It examines their mechanisms of biofilm formation, antibiotic resistance, and the challenges they present in clinical treatment. Various antibiofilm strategies have shown promise in vitro and in animal studies, including the use of N-acetylcysteine, enzymes like dispersin B, and agents disrupting quorum sensing and biofilm matrix components. However, their clinical application, particularly in children, remains limited. Traditional treatments for biofilm-associated diseases have not significantly evolved, even with biofilm detection. The transition from experimental findings to clinical practice is complex and requires robust clinical trials and standardized biofilm detection protocols. Addressing biofilms in pediatric respiratory infections is crucial for improving treatment outcomes and managing recurrent and chronic diseases effectively.}, }
@article {pmid39203351, year = {2024}, author = {Liang, J and Zheng, X and Ning, T and Wang, J and Wei, X and Tan, L and Shen, F}, title = {Revealing the Viable Microbial Community of Biofilm in a Sewage Treatment System Using Propidium Monoazide Combined with Real-Time PCR and Metagenomics.}, journal = {Microorganisms}, volume = {12}, number = {8}, pages = {}, pmid = {39203351}, issn = {2076-2607}, support = {42307051//National Natural Science Foundation of China/ ; 2022M713416//China Postdoctoral Science Foundation/ ; CAAS-ZDRW202306//Special Fund for Basic Scientific Research of Central Public Welfare Institutes/ ; }, abstract = {Microbial community composition, function, and viability are important for biofilm-based sewage treatment technologies. Most studies of microbial communities mainly rely on the total deoxyribonucleic acid (DNA) extracted from the biofilm. However, nucleotide materials released from dead microorganisms may interfere with the analysis of viable microorganisms and their metabolic potential. In this study, we developed a protocol to assess viability as well as viable community composition and function in biofilm in a sewage treatment system using propidium monoazide (PMA) coupled with real-time quantitative polymerase chain reaction (qPCR) and metagenomic technology. The optimal removal of PMA from non-viable cells was achieved by a PMA concentration of 4 μM, incubation in darkness for 5 min, and exposure for 5 min. Simultaneously, the detection limit can reach a viable bacteria proportion of 1%, within the detection concentration range of 10[2]-10[8] CFU/mL (colony forming unit/mL), showing its effectiveness in removing interference from dead cells. Under the optimal conditions, the result of PMA-metagenomic sequencing revealed that 6.72% to 8.18% of non-viable microorganisms were influenced and the composition and relative abundance of the dominant genera were changed. Overall, this study established a fast, sensitive, and highly specific biofilm viability detection method, which could provide technical support for accurately deciphering the structural composition and function of viable microbial communities in sewage treatment biofilms.}, }
@article {pmid39203113, year = {2024}, author = {Išljamović, M and Bonvin, D and Milojević, M and Stojanović, S and Spasić, M and Stojković, B and Janošević, P and Otašević, S and Ebersold, MM}, title = {Antifungal Effect of Poly(methyl methacrylate) with Farnesol and Undecylenic Acid against Candida albicans Biofilm Formation.}, journal = {Materials (Basel, Switzerland)}, volume = {17}, number = {16}, pages = {}, pmid = {39203113}, issn = {1996-1944}, support = {No. 2014.0040/Serbia///Swiss Government Excellence Scholarship/ ; }, abstract = {The control of Candida albicans biofilm formation on dentures made of poly(methyl methacrylate) (PMMA) is an important challenge due to the high resistance to antifungal drugs. Interestingly, the natural compounds undecylenic acid (UDA) and farnesol (FAR) both prevent C. albicans biofilm formation and could have a synergetic effect. We therefore modified PMMA with a combination of UDA and FAR (UDA+FAR), aiming to obtain the antifungal PMMA_UDA+FAR composites. Equal concentrations of FAR and UDA were added to PMMA to reach 3%, 6%, and 9% in total of both compounds in composites. The physico-chemical properties of the composites were characterized by Fourier-transform infrared spectroscopy and water contact angle measurement. The antifungal activity of the composites was tested on both biofilm and planktonic cells with an XTT test 0 and 6 days after the composites' preparation. The effect of the UDA+FAR combination on C. albicans filamentation was studied in agar containing 0.0125% and 0.4% UDA+FAR after 24 h and 48 h of incubation. The results showed the presence of UDA and FAR on the composite and decreases in the water contact angle and metabolic activity of both the biofilm and planktonic cells at both time points at non-toxic UDA+FAR concentrations. Thus, the modification of PMMA with a combination of UDA+FAR reduces C. albicans biofilm formation on dentures and could be a promising anti-Candida strategy.}, }
@article {pmid39202995, year = {2024}, author = {Bugyna, L and Bilská, K and Boháč, P and Pribus, M and Bujdák, J and Bujdáková, H}, title = {Anti-Biofilm Effect of Hybrid Nanocomposite Functionalized with Erythrosine B on Staphylococcus aureus Due to Photodynamic Inactivation.}, journal = {Molecules (Basel, Switzerland)}, volume = {29}, number = {16}, pages = {}, pmid = {39202995}, issn = {1420-3049}, support = {EU Next Generation EU through the Recovery and Resilience Plan for Slovakia under the project No. 09I03-03-V01-00105//Government Office of the Slovak Republic/ ; APVV-21- 0302//Slovak Research and Development Agency/ ; APVV-22-0150//Slovak Research and Development Agency/ ; VEGA 1/0240/23//Ministry of Education, Research, Development and Youth/ ; }, mesh = {*Biofilms/drug effects ; *Nanocomposites/chemistry ; *Staphylococcus aureus/drug effects ; *Erythrosine/pharmacology/chemistry ; Polyurethanes/chemistry/pharmacology ; Anti-Bacterial Agents/pharmacology/chemistry ; Photosensitizing Agents/pharmacology/chemistry ; Silicates/chemistry/pharmacology ; Photochemotherapy/methods ; Polyelectrolytes ; }, abstract = {Resistant biofilms formed by Staphylococcus aureus on medical devices pose a constant medical threat. A promising alternative to tackle this problem is photodynamic inactivation (PDI). This study focuses on a polyurethane (PU) material with an antimicrobial surface consisting of a composite based on silicate, polycation, and erythrosine B (EryB). The composite was characterized using X-ray diffraction and spectroscopy methods. Anti-biofilm effectiveness was determined after PDI by calculation of CFU mL[-1]. The liquid PU precursors penetrated a thin silicate film resulting in effective binding of the PU/silicate composite and the PU bulk phases. The incorporation of EryB into the composite matrix did not significantly alter the spectral properties or photoactivity of the dye. A green LED lamp and laser were used for PDI, while irradiation was performed for different periods. Preliminary experiments with EryB solutions on planktonic cells and biofilms optimized the conditions for PDI on the nanocomposite materials. Significant eradication of S. aureus biofilm on the composite surface was achieved by irradiation with an LED lamp and laser for 1.5 h and 10 min, respectively, resulting in a 10,000-fold reduction in biofilm growth. These results demonstrate potential for the development of antimicrobial polymer surfaces for modification of medical materials and devices.}, }
@article {pmid39202793, year = {2024}, author = {Fehlhofer, J and Ries, J and Nickel, FT and Rothhammer, V and Schwab, S and Kesting, M and Buchbender, M}, title = {Correction: Fehlhofer et al. Expression of Inflammatory Mediators in Biofilm Samples and Clinical Association in Multiple Sclerosis Patients in Remission-A Pilot Study. Life 2024, 14, 367.}, journal = {Life (Basel, Switzerland)}, volume = {14}, number = {8}, pages = {}, pmid = {39202793}, issn = {2075-1729}, abstract = {References [...].}, }
@article {pmid39201405, year = {2024}, author = {Ruiz-Mazón, L and Ramírez-Rico, G and de la Garza, M}, title = {Lactoferrin Affects the Viability of Bacteria in a Biofilm and the Formation of a New Biofilm Cycle of Mannheimia haemolytica A2.}, journal = {International journal of molecular sciences}, volume = {25}, number = {16}, pages = {}, pmid = {39201405}, issn = {1422-0067}, support = {992577//Conahcyt/ ; CB-A1-S-8989//Conahcyt/ ; }, mesh = {*Biofilms ; *Mannheimia haemolytica/drug effects/physiology ; *Lactoferrin/pharmacology ; *Microbial Viability/drug effects ; Animals ; Cattle ; Bacterial Proteins/metabolism ; }, abstract = {Respiratory diseases in ruminants are responsible for enormous economic losses for the dairy and meat industry. The main causative bacterial agent of pneumonia in ovine is Mannheimia haemolytica A2. Due to the impact of this disease, the effect of the antimicrobial protein, bovine lactoferrin (bLf), against virulence factors of this bacterium has been studied. However, its effect on biofilm formation has not been reported. In this work, we evaluated the effect on different stages of the biofilm. Our results reveal a decrease in biofilm formation when bacteria were pre-incubated with bLf. However, when bLf was added at the start of biofilm formation and on mature biofilm, an increase was observed, which was visualized by greater bacterial aggregation and secretion of biofilm matrix components. Additionally, through SDS-PAGE, a remarkable band of ~80 kDa was observed when bLf was added to biofilms. Therefore, the presence of bLf on the biofilm was determined through the Western blot and Microscopy techniques. Finally, by using Live/Dead staining, we observed that most of the bacteria in a biofilm with bLf were not viable. In addition, bLf affects the formation of a new biofilm cycle. In conclusion, bLf binds to the biofilm of M. haemolytica A2 and affects the viability of bacteria and the formation a new biofilm cycle.}, }
@article {pmid39200500, year = {2024}, author = {Liu, Y and Liu, Y and Hao, L and Cao, J and Jiang, L and Yi, H}, title = {Metabolomic Approaches to Study the Potential Inhibitory Effects of Plantaricin Q7 against Listeria monocytogenes Biofilm.}, journal = {Foods (Basel, Switzerland)}, volume = {13}, number = {16}, pages = {}, pmid = {39200500}, issn = {2304-8158}, support = {32172180//National Natural Science Foundation of China/ ; ZR2020KC009//Key Program of Natural Science Foundation of Shandong Province in China/ ; }, abstract = {Listeria monocytogenes is a serious pathogen and can exacerbate harmful effects through the formation of biofilm. Inhibition of or reduction in L. monocytogenes biofilm is a promising strategy to control L. monocytogenes in the food industry. In our previous study, it was found that plantaricin Q7 produced by Lactiplantibacillus plantarum Q7 could inhibit and reduce L. monocytogenes biofilm, but the specific mechanism remains unclear. In this study, the inhibitive and reduced activity of plantaricin Q7 on L. monocytogenes biofilm was investigated by metabolomics. The results showed that plantaricin Q7 inhibited the synthesis of L. monocytogenes biofilm mainly through purine metabolism and glycerol phospholipid metabolism, and the key differential metabolites included acetylcholine and hypoxanthine with a decrease in abundance from 5.80 to 4.85. In addition, plantaricin Q7 reduced the formed L. monocytogenes biofilm by purine metabolism and arginine biosynthesis, and the main differential metabolites were N-acetylglutamate and D-ribose-1-phosphate with a decrease in abundance from 6.21 to 4.73. It was the first report that purine metabolism and amino acid metabolism were the common metabolic pathway for plantaricin Q7 to inhibit and reduce L. monocytogenes biofilm, which could be potential targets to control L. monocytogenes biofilm. A putative metabolic pathway for L. monocytogenes biofilm inhibition and reduction by plantaricin Q7 was proposed. These findings provided a novel strategy to control L. monocytogenes biofilm in food processing.}, }
@article {pmid39200422, year = {2024}, author = {Wei, J and Zhang, X and Ismael, M and Zhong, Q}, title = {Anti-Biofilm Effects of Z102-E of Lactiplantibacillus plantarum against Listeria monocytogenes and the Mechanism Revealed by Transcriptomic Analysis.}, journal = {Foods (Basel, Switzerland)}, volume = {13}, number = {16}, pages = {}, pmid = {39200422}, issn = {2304-8158}, support = {2024A1515012695//Guangdong Basic and Applied Basic Research Foundation/ ; 31972046//National Natural Science Foundation of China/ ; 2020B1212060059//Science and Technology Projects of Guangdong Province/ ; }, abstract = {Lactic acid bacteria (LAB) are the most common probiotics, and they present excellent inhibitory effects on pathogenic bacteria. This study aimed to explore the anti-biofilm potential of the purified active substance of Lactiplantibacillus plantarum, named Z102-E. The effects of Z102-E on Listeria monocytogenes were investigated in detail, and a transcriptomic analysis was conducted to reveal the anti-biofilm mechanism. The results indicated that the sub-MIC of Z102-E (3.2, 1.6, and 0.8 mg/mL) decreased the bacterial growth and effectively reduced the self-aggregation, surface hydrophobicity, sugar utilization, motility, biofilm formation, AI-2 signal molecule, contents of extracellular polysaccharides, and extracellular protein of L. monocytogenes. Moreover, the inverted fluorescence microscopy observation confirmed the anti-biofilm effect of Z102-E. The transcriptomic analysis indicated that 117 genes were up-regulated and 214 were down-regulated. Z102-E regulated the expressions of genes related to L. monocytogenes quorum sensing, biofilm formation, etc. These findings suggested that Z102-E has great application potential as a natural bacteriostatic agent.}, }
@article {pmid39200087, year = {2024}, author = {Mishra, A and Tabassum, N and Aggarwal, A and Kim, YM and Khan, F}, title = {Artificial Intelligence-Driven Analysis of Antimicrobial-Resistant and Biofilm-Forming Pathogens on Biotic and Abiotic Surfaces.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {8}, pages = {}, pmid = {39200087}, issn = {2079-6382}, support = {RS-2023-00241461//Ministry of Education/ ; 2023 (202315350001)//Pukyong National University/ ; }, abstract = {The growing threat of antimicrobial-resistant (AMR) pathogens to human health worldwide emphasizes the need for more effective infection control strategies. Bacterial and fungal biofilms pose a major challenge in treating AMR pathogen infections. Biofilms are formed by pathogenic microbes encased in extracellular polymeric substances to confer protection from antimicrobials and the host immune system. Biofilms also promote the growth of antibiotic-resistant mutants and latent persister cells and thus complicate therapeutic approaches. Biofilms are ubiquitous and cause serious health risks due to their ability to colonize various surfaces, including human tissues, medical devices, and food-processing equipment. Detection and characterization of biofilms are crucial for prompt intervention and infection control. To this end, traditional approaches are often effective, yet they fail to identify the microbial species inside biofilms. Recent advances in artificial intelligence (AI) have provided new avenues to improve biofilm identification. Machine-learning algorithms and image-processing techniques have shown promise for the accurate and efficient detection of biofilm-forming microorganisms on biotic and abiotic surfaces. These advancements have the potential to transform biofilm research and clinical practice by allowing faster diagnosis and more tailored therapy. This comprehensive review focuses on the application of AI techniques for the identification of biofilm-forming pathogens in various industries, including healthcare, food safety, and agriculture. The review discusses the existing approaches, challenges, and potential applications of AI in biofilm research, with a particular focus on the role of AI in improving diagnostic capacities and guiding preventative actions. The synthesis of the current knowledge and future directions, as described in this review, will guide future research and development efforts in combating biofilm-associated infections.}, }
@article {pmid39200075, year = {2024}, author = {Jantaruk, P and Teerapo, K and Charoenwutthikun, S and Roytrakul, S and Kunthalert, D}, title = {Anti-Biofilm and Anti-Inflammatory Properties of the Truncated Analogs of the Scorpion Venom-Derived Peptide IsCT against Pseudomonas aeruginosa.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {8}, pages = {}, pmid = {39200075}, issn = {2079-6382}, support = {R2565B051, PHD/0050/2559//Naresuan University (NU) and National Science, Research and Innovation Fund (NSRF), and The Royal Golden Jubilee Ph.D. (RGJ-PHD) Program Scholarship,/ ; }, abstract = {Pseudomonas aeruginosa is an opportunistic pathogen in humans and a frequent cause of severe nosocomial infections and fatal infections in immunocompromised individuals. Its ability to form biofilms has been the main driving force behind its resistance to almost all conventional antibiotics, thereby limiting treatment efficacy. In an effort to discover novel therapeutic agents to fight P. aeruginosa-associated biofilm infections, the truncated analogs of scorpion venom-derived peptide IsCT were synthesized and their anti-biofilm properties were examined. Among the investigated peptides, the IsCT-Δ6-8 peptide evidently showed the most potential anti-P. aeruginosa biofilm activity and the effect was not due to bacterial growth inhibition. The IsCT-Δ6-8 peptide also exhibited inhibitory activity against the production of pyocyanin, an important virulence factor of P. aeruginosa. Furthermore, the IsCT-Δ6-8 peptide significantly suppressed the production of inflammatory mediators nitric oxide and interleukin-6 in P. aeruginosa LPS-induced macrophages. Due to its low cytotoxicity to mammalian cells, the IsCT-Δ6-8 peptide emerges as a promising candidate with significant anti-biofilm and anti-inflammatory properties. These findings highlight its potential application in treating P. aeruginosa-related biofilm infections.}, }
@article {pmid39200043, year = {2024}, author = {Manuschai, J and Sotozono, M and Takenaka, S and Kornsombut, N and Takahashi, R and Saito, R and Nagata, R and Ida, T and Noiri, Y}, title = {In Vitro Inhibitory Effect of Silver Diamine Fluoride Combined with Potassium Iodide against Mixed-Species Biofilm Formation on Human Root Dentin.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {8}, pages = {}, pmid = {39200043}, issn = {2079-6382}, support = {JP21H03117B//Japan society for the promotion of science/ ; 21K16990//Japan society for the promotion of science/ ; }, abstract = {Applying a saturated potassium iodide (KI) solution immediately after silver diamine fluoride (SDF) application may affect the inhibitory effects of SDF on biofilm formation. This study compared the efficacy of 38% SDF with and without KI on preventing mixed-species biofilm formation on human root dentin surfaces and assessed ion incorporation into root dentin. The biofilms, composed of Streptococcus mutans, Lactobacillus rhamnosus, and Actinomyces naeslundii, were grown on specimen surfaces treated with either SDF or SDF + KI. After 24 h, the biofilms were evaluated using scanning electron microscopy, live/dead staining, adenosine triphosphate (ATP) assays, colony-forming unit (CFU) counts, and quantitative polymerase chain reaction. A Mann-Whitney U test was used to compare the results between the groups. Ion incorporation was assessed using an electron probe microanalyzer. The relative ATP content in the SDF + KI group was significantly higher than that in the SDF group (p < 0.05). However, biofilm morphology and the logarithmic reduction in CFUs and bacterial DNA were comparable across the groups. The SDF + KI treatment resulted in less silver and fluoride ion incorporation than that yielded by SDF alone. The inhibitory effects of SDF and SDF + KI on mixed-species biofilm formation were almost equivalent, although KI application affected the ion incorporation.}, }
@article {pmid39200019, year = {2024}, author = {Santiago, MB and Tanimoto, MH and Ambrosio, MALV and Veneziani, RCS and Bastos, JK and Sabino-Silva, R and Martins, CHG}, title = {The Antibacterial Potential of Brazilian Red Propolis against the Formation and Eradication of Biofilm of Helicobacter pylori.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {8}, pages = {}, pmid = {39200019}, issn = {2079-6382}, support = {2017/04138-8//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado de S&#xe3;o Paulo/ ; Finance code 001//Coordena&#xe7;&#xe3;o de Aperfeicoamento de Pessoal de N&#xed;vel Superior/ ; 307974/2019-7 and 409157/2022-8 and 384347/2023-1//National Council for Scientific and Technological Development/ ; }, abstract = {Helicobacter pylori is associated with gastrointestinal diseases, and its treatment is challenging due to antibiotic-resistant strains, necessitating alternative therapies. Brazilian red propolis (BRP), known for its diverse bioactive compounds with pharmaceutical properties, was investigated for its anti-H. pylori activity, focusing on biofilm formation inhibition and eradication. BRP was tested against H. pylori (ATCC 43526) using several assays: time-kill, nucleotide leakage, biofilm formation inhibition (determining the minimum inhibitory concentration of biofilm of 50%-MICB50, and cell viability), and biofilm eradication (determining the minimum eradication concentration of biofilm of 99.9%-MBEC). Standardization of H. pylori biofilm formation was also conducted. In the time-kill assay, BRP at 50 µg/mL eliminated all H. pylori cells after 24 h. The nucleotide leakage assay showed no significant differences between control groups and BRP-treated groups at 25 µg/mL and 50 µg/mL. H. pylori formed biofilms in vitro at 10[9] CFU/mL after 72 h. The MICB50 of BRP was 15.6 µg/mL, and at 500, 1000, and 2000 µg/mL, BRP eradicated all bacterial cells. The MBEC was 2000 µg/mL. These findings suggest that BRP has promising anti-H. pylori activity, effectively inhibiting and eradicating biofilms. Further studies are necessary to elucidate BRP's mechanisms of action against H. pylori.}, }
@article {pmid39199989, year = {2024}, author = {Chakraborty, S and Baindara, P and Sharma, P and Jose T, A and V, K and Manoharan, R and Mandal, SM}, title = {Anti-Biofilm Action of Cineole and Hypericum perforatum to Combat Pneumonia-Causing Drug-Resistant P. aeruginosa.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {8}, pages = {}, pmid = {39199989}, issn = {2079-6382}, abstract = {Hospital-acquired antibiotic-resistant pneumonia is one of the major causes of mortality around the world that pose a catastrophic threat. Pseudomonas aeruginosa is one of the most significant opportunistic pathogens responsible for hospital-acquired pneumonia and gained resistance to the majority of conventional antibiotics. There is an urgent need for antibiotic alternatives to control drug-resistant pneumonia and other related respiratory infections. In the present study, we explored the antibacterial potential of cineole in combination with homeopathic medicines against biofilm-forming drug-resistant P. aeruginosa. Out of 26 selected and screened homeopathic medicines, Hypericum Perforatum (HyPer) was found to eradicate biofilm-forming drug-resistant P. aeruginosa most effectively when used in combination with cineole. Interestingly, the synergistic action of HyPer and cineole was also found to be similarly effective against planktonic cells of P. aeruginosa. Further, the potential synergistic killing mechanisms of cineole and HyPer were determined by analyzing zeta membrane potential, outer membrane permeability, and DNA release from P. aeruginosa cells upon treatment with cineole and HyPer. Additionally, molecular docking analysis revealed strong binding affinities of hypericin (an active ingredient of HyPer) with the PqsA (a quorum sensing protein) of P. aeruginosa. Overall, our findings revealed the potential synergistic action of cineole and HyPer against biofilm-forming drug-resistant P. aeruginosa. Cineole and HyPer could be used in combination with other bronchodilators as inhalers to control the biofilm-forming drug-resistant P. aeruginosa.}, }
@article {pmid39199988, year = {2024}, author = {Vintilă, C and Coșeriu, RL and Mare, AD and Ciurea, CN and Togănel, RO and Simion, A and Cighir, A and Man, A}, title = {Biofilm Formation and Antibiotic Resistance Profiles in Carbapenemase-Producing Gram-Negative Rods-A Comparative Analysis between Screening and Pathological Isolates.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {8}, pages = {}, pmid = {39199988}, issn = {2079-6382}, abstract = {(1) Background: Carbapenem-resistant (CR) bacteria pose a significant global public health challenge due to their ability to evade treatment with beta-lactam antibiotics, including carbapenems. This study investigates the biofilm-forming capabilities of CR clinical bacterial isolates and examines the impact of serum on biofilm formation. Additionally, the study evaluates the resistance profiles and genetic markers for carbapenemase production. (2) Methods: Bacterial isolates were collected from the microbiology laboratory of Mures County Clinical Hospital between October 2022 and September 2023. Pharyngeal and rectal swabs were screened for carbapenem-resistant bacteria using selective media. Lower respiratory tract samples were also analyzed for CR Gram-negative bacteria. The isolates were tested for their ability to form biofilms in the presence and absence of fetal bovine serum at 24 and 48 h. Carbapenemase production was detected phenotypically and confirmed via PCR for relevant genes. (3) Results: Out of 846 screened samples, 4.25% from pharyngeal swabs and 6.38% from rectal swabs tested positive for CR bacteria. Acinetobacter baumannii and Klebsiella pneumoniae were the most common species isolated. Biofilm formation varied significantly between clinical isolates and standard strains, with clinical isolates generally showing higher biofilm production. The presence of serum had no significant effect on biofilm formation in Klebsiella spp., but stimulated biofilm formation for Acinetobacter spp. Carbapenemase genes blaKPC, blaOXA-48-like, and blaNDM were detected in various isolates, predominantly in Klebsiella spp., but were not the main determinants of carbapenem resistance, at least in screening isolates. (4) Conclusions: This study highlights the variability in biofilm formation among CR clinical isolates and underscores the differences between the bacteria found as carriage versus infection. Both bacterial species and environmental factors variably influence biofilm formation. These insights are crucial for the development of effective treatment and infection control strategies in clinical settings.}, }
@article {pmid39199987, year = {2024}, author = {David, A and Tahrioui, A and Tareau, AS and Forge, A and Gonzalez, M and Bouffartigues, E and Lesouhaitier, O and Chevalier, S}, title = {Pseudomonas aeruginosa Biofilm Lifecycle: Involvement of Mechanical Constraints and Timeline of Matrix Production.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {8}, pages = {}, pmid = {39199987}, issn = {2079-6382}, abstract = {Pseudomonas aeruginosa is an opportunistic pathogen causing acute and chronic infections, especially in immunocompromised patients. Its remarkable adaptability and resistance to various antimicrobial treatments make it difficult to eradicate. Its persistence is enabled by its ability to form a biofilm. Biofilm is a community of sessile micro-organisms in a self-produced extracellular matrix, which forms a scaffold facilitating cohesion, cell attachment, and micro- and macro-colony formation. This lifestyle provides protection against environmental stresses, the immune system, and antimicrobial treatments, and confers the capacity for colonization and long-term persistence, often characterizing chronic infections. In this review, we retrace the events of the life cycle of P. aeruginosa biofilm, from surface perception/contact to cell spreading. We focus on the importance of extracellular appendages, mechanical constraints, and the kinetics of matrix component production in each step of the biofilm life cycle.}, }
@article {pmid39199983, year = {2024}, author = {Artesani, L and Ciociola, T and Vismarra, A and Bacci, C and Conti, S and Giovati, L}, title = {Activity of Synthetic Peptide KP and Its Derivatives against Biofilm-Producing Escherichia coli Strains Resistant to Cephalosporins.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {8}, pages = {}, pmid = {39199983}, issn = {2079-6382}, support = {Bando di Ateneo 2021 per la ricerca co-funded by MUR-Italian Ministry of Universities and Research - D.M. 737/2021 - PNR - PNRR - NextGenerationEU.//University of Parma/ ; }, abstract = {Bacterial resistance to β-lactam antibiotics, particularly new generation cephalosporins, is a major public health concern. In Escherichia coli, resistance to these antibiotics is mainly mediated by extended-spectrum β-lactamases (ESBL), which complicates a range of health-threatening infections. These infections may also be biofilm-related, making them more difficult to treat because of the higher tolerance to conventional antibiotics and the host immune response. In this study, we tested as potential new drug candidates against biofilm-forming ESBL-producing E. coli four antimicrobial peptides previously shown to have antifungal properties. The peptides proved to be active in vitro at micromolar concentrations against both sensitive and ESBL-producing E. coli strains, effectively killing planktonic cells and inhibiting biofilm formation. Quantitative fluorescence intensity analysis of three-dimensional reconstructed confocal laser scanning microscopy (CLSM) images of mature biofilm treated with the most active peptide showed significant eradication and a reduction in viable bacteria, while scanning electron microscopy (SEM) revealed gross morphological alterations in treated bacteria. The screening of the investigated peptides for antibacterial and antibiofilm activity led to the selection of a leading candidate to be further studied for developing new antimicrobial drugs as an alternative treatment against microbial infections, primarily associated with biofilms.}, }
@article {pmid39198733, year = {2024}, author = {Crossman, L and Sims, L and Dean, R and Felgate, H and Calvo, TD and Hill, C and McNamara, I and Webber, MA and Wain, J}, title = {Sticking together: independent evolution of biofilm formation in different species of staphylococci has occurred multiple times via different pathways.}, journal = {BMC genomics}, volume = {25}, number = {1}, pages = {812}, pmid = {39198733}, issn = {1471-2164}, mesh = {*Biofilms/growth &amp; development ; *Staphylococcus/genetics/physiology ; Phylogeny ; Bacterial Proteins/genetics/metabolism ; Evolution, Molecular ; }, abstract = {BACKGROUND: Staphylococci cause a wide range of infections, including implant-associated infections which are difficult to treat due to the presence of biofilms. Whilst some proteins involved in biofilm formation are known, the differences in biofilm production between staphylococcal species remains understudied. Currently biofilm formation by Staphylococcus aureus is better understood than other members of the genus as more research has focused on this species.<br><br>RESULTS: We assembled a panel of 385 non-aureus Staphylococcus isolates of 19 species from a combination of clinical sources and reference strains. We used a high-throughput crystal violet assay to assess the biofilm forming ability of all strains and assign distinct biofilm formation categories. We compared the prevalence of Pfam domains between the categories and used machine learning to identify amino acid 20-mers linked to biofilm formation. This identified some domains within proteins already linked to biofilm formation and important domains not previously linked to biofilm formation in staphylococci. RT-qPCR confirmed the expression of selected genes predicted to encode important domains within biofilms in Staphylococcus epidermidis. The prevalence and distribution of biofilm associated domains showed a link to phylogeny, suggesting different Staphylococcus species have independently evolved different mechanisms of biofilm production.<br><br>CONCLUSIONS: This work has identified different routes to biofilm formation in diverse species of Staphylococcus and suggests independent evolution of biofilm has occurred multiple times across the genus. Understanding the mechanisms of biofilm formation in any given species is likely to require detailed study of relevant strains and the ability to generalise across the genus may be limited.}, }
@article {pmid39198017, year = {2024}, author = {Mnisi, TJ and Matotoka, MM and Masoko, P}, title = {Antioxidant, antibacterial, and anti-biofilm activities of selected indigenous plant species against nosocomial bacterial pathogens.}, journal = {Letters in applied microbiology}, volume = {77}, number = {9}, pages = {}, doi = {10.1093/lambio/ovae080}, pmid = {39198017}, issn = {1472-765X}, support = {SFH160713177859//National Research Foundation of South Africa/ ; }, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology ; *Plant Extracts/pharmacology/chemistry ; *Antioxidants/pharmacology/chemistry ; *Microbial Sensitivity Tests ; Cross Infection/microbiology ; Artemia/drug effects ; Bacteria/drug effects ; Animals ; Pseudomonas aeruginosa/drug effects ; }, abstract = {Biofilms are responsible for over 60% of nosocomial infections. The focus of this study was to investigate the antioxidant, antibacterial, antibiofilm, and anti-motility activities of Gardenia volkensii, Carissa bispinosa, Peltophorum africanum, and Senna petersiana. Antioxidant activity was evaluated using free radical (DPPH) scavenging and ferric reducing power assays. Antibacterial and antibiofilm activities were evaluated using the broth micro-dilution and the crystal violet assays, respectively. Anti-motility was evaluated using anti-swarming activities, and the brine shrimp lethality assay was used for cytotoxicity. Gardenia volkensii and C. bispinosa acetone extracts had low EC50 values of 9.59 and 9.99 μg ml-1on the free-radical scavenging activity, respectively. All the plant extracts demonstrated broad-spectrum antibacterial activity against Klebsiella pneumoniae, Pseudomonasa aeruginosa, Escherichia coli, Enterococcus faecalis, and Staphylococcus aureus [minimum inhibitory concentration (MIC) < 0.63 mg ml-1]. The initial cell adherence stage of P. aeruginosa and E. coli was the most susceptible stage where sub-MICs resulted in inhibitions >50%. Peltophorum africanum had the least cytotoxic effects. All extracts had anti-motility activity against P. aeruginosa and E. coli. This study showed that not only do the plants have strong antibacterial activity but had noteworthy inhibition (>50%) of initial cell adherence and may be suitable candidates for the treatment of nosocomial pathogens.}, }
@article {pmid39197770, year = {2024}, author = {Yang, Y and Zhu, Y and Gan, D and Cai, X and Li, X and Liu, X and Xia, S}, title = {Enhancing biofilm formation with powder carriers for efficient nitrogen and phosphorus removal.}, journal = {The Science of the total environment}, volume = {951}, number = {}, pages = {175812}, doi = {10.1016/j.scitotenv.2024.175812}, pmid = {39197770}, issn = {1879-1026}, mesh = {*Phosphorus ; *Waste Disposal, Fluid/methods ; *Nitrogen ; *Zeolites/chemistry ; *Biofilms ; *Sewage/microbiology ; *Wastewater/microbiology/chemistry ; Magnesium Compounds ; Silicon Compounds ; Water Pollutants, Chemical/analysis ; Powders ; Bioreactors/microbiology ; }, abstract = {This study assesses the improvement in nitrogen and phosphorus removal from wastewater achieved through the integration of zeolite and attapulgite carrier materials into the activated sludge (AS) process. It was found that the addition of these materials significantly enhanced the processing performance of the reactor. Specifically, the use of zeolite and attapulgite powders increased sludge particle sizes to averages of 231.56 μm and 219.62 μm, respectively. This facilitated micro-granule formation, substantially improving the settling characteristics of the sludge and boosting the activity and proliferation of essential microbes. Illumina MiSeq sequencing demonstrated significant accumulations of DGAOs (Candidatus_Competibacter) and DPAOs (Candidatus_Accumulibacter). Furthermore, these carriers augmented the protein content in extracellular polymers, enhancing the hydrophobicity of the sludge and promoting aggregation. Comparative analysis based on the extended Derjaguin, Landau, Verwey, and Overbeek (DLVO) theory indicated a preferential adhesion affinity of sludge for zeolite compared to attapulgite, attributed primarily to Lewis acid-base and electric double-layer interactions. These findings underscore zeolite's enhanced efficacy in biomass fixation and suggest significant potential for the technological advancement of wastewater treatment plants.}, }
@article {pmid39197692, year = {2024}, author = {Zhou, Y and Chang, J and Zhang, M and Li, X and Yang, W and Hu, L and Zhou, D and Ni, B and Lu, R and Zhang, Y}, title = {VPA0198, a GGDEF domain-containing protein, affects the motility and biofilm formation of Vibrio parahaemolyticus and is regulated by quorum sensing associated regulators.}, journal = {Microbial pathogenesis}, volume = {195}, number = {}, pages = {106882}, doi = {10.1016/j.micpath.2024.106882}, pmid = {39197692}, issn = {1096-1208}, mesh = {*Vibrio parahaemolyticus/genetics/metabolism/physiology ; *Biofilms/growth &amp; development ; *Quorum Sensing/genetics ; *Cyclic GMP/analogs &amp; derivatives/metabolism ; *Bacterial Proteins/genetics/metabolism ; *Gene Expression Regulation, Bacterial ; Transcription Factors ; }, abstract = {Cyclic di-GMP (c-di-GMP), a ubiquitous secondary messenger in bacteria, affects multiple bacterial behaviors including motility and biofilm formation. c-di-GMP is synthesized by diguanylate cyclase harboring a GGDEF domain and degraded by phosphodiesterase harboring an either EAL or HD-GYP domain. Vibrio parahaemolyticus, the leading cause of seafood-associated gastroenteritis, harbors more than 60 genes involved in c-di-GMP metabolism. However, roles of most of these genes including vpa0198, which encodes a GGDEF-domain containing protein, are still completely unknown. AphA and OpaR are the master quorum sensing (QS) regulators operating at low (LCD) and high cell density (HCD), respectively. QsvR integrates into QS to control gene expression via direct regulation of AphA and OpaR. In this study, we showed that deletion of vpa0198 remarkably reduced c-di-GMP production and biofilm formation, whereas promoted the swimming motility of V. parahaemolyticus. Overexpression of VPA0198 in the vpa0198 mutant strain significantly reduced the swimming and swarming motility and enhanced the biofilm formation ability of V. parahaemolyticus. In addition, transcription of vpa0198 was under the collective regulation of AphA, OpaR and QsvR. AphA activated the transcription of vpa0198 at LCD, whereas QsvR and OpaR coordinately and directly repressed vpa0198 transcription at HCD, thereby leading to a cell density-dependent expression of vpa0198. Therefore, this work expanded the knowledge of synthetic regulatory mechanism of c-di-GMP in V. parahaemolyticus.}, }
@article {pmid39197659, year = {2024}, author = {Wang, X and Zhang, J and Li, L and Zhu, Y and Zhang, Y and Ni, M and Ding, Y and Huang, Y and Pan, Y}, title = {Formation mechanism of high biofilm phosphorus storage capacity and its effect on phosphorus uptake-release and carbon source consumption.}, journal = {Bioresource technology}, volume = {412}, number = {}, pages = {131363}, doi = {10.1016/j.biortech.2024.131363}, pmid = {39197659}, issn = {1873-2976}, mesh = {*Phosphorus/metabolism ; *Biofilms ; *Carbon/metabolism ; *Bioreactors ; Wastewater/chemistry ; }, abstract = {Phosphorus recovery from wastewater is an effective method to alleviate the shortage of phosphorus resources. The biofilm phosphorus recovery process can realize simultaneous removal and enrichment of phosphorus in wastewater. In this study, a sequencing batch biofilm reactor was constructed to study the rapid phosphorus release and slow phosphorus release stages in the phosphorus recovery cycle. The relationship between high biofilm phosphorus storage capacity (Pbiofilm), phosphorus recovery solution concentration, phosphorus uptake-release behavior and carbon source consumption were explored. The increase in phosphorus recovery solution concentration promotes the elevation of Pbiofilm, which, conversely promotes phosphorus release in the next recovery cycle. In addition, the distinct phosphorus uptake-release characteristics of extracellular polymeric substances and cells were illustrated. This study provides a theoretical foundation to elevate the phosphorus recovery efficiency and reduce carbon source consumption in biofilm phosphorus recovery process.}, }
@article {pmid39197632, year = {2024}, author = {Huang, B and Xiao, F and Chen, Z and Hu, T and Qiu, R and Wang, W and You, W and Su, X and Hu, W and Wang, Z}, title = {Coaxial electrospun nanofiber accelerates infected wound healing via engineered probiotic biofilm.}, journal = {International journal of biological macromolecules}, volume = {279}, number = {Pt 1}, pages = {135100}, doi = {10.1016/j.ijbiomac.2024.135100}, pmid = {39197632}, issn = {1879-0003}, mesh = {*Nanofibers/chemistry ; *Wound Healing/drug effects ; *Biofilms/drug effects ; *Probiotics/pharmacology ; Animals ; *Anti-Bacterial Agents/pharmacology ; *Fibroins/chemistry/pharmacology ; Mice ; Polyesters/chemistry ; Staphylococcus aureus/drug effects ; }, abstract = {Bacterial infection is the primary cause of delayed wound healing. Infected wounds suffer from a series of harmful factors in the harsh wound microenvironment (WME), greatly damaging their potential for tissue regeneration. Herein, a novel probiotic biofilm-based antibacterial strategy is proposed through experimentation. Firstly, a series of coaxial polycaprolactone (PCL) / silk fibroin (SF) nanofiber films (termed as PSN-n, n = 0.5, 1.0, 1.5, and 2.0, respectively) are prepared by coaxial electrospinning and their physiochemical properties are comprehensively characterized. Afterward, the PSN-1.5 is selected and co-cultured with L. paracasei to allow the formation of probiotic biofilm. The probiotic biofilm-loaded PSN-1.5 nanofiber film (termed as PSNL-1.5) exhibits relatively good broad-spectrum antibacterial activity, biocompatibility, and enhanced pro-regenerative capability by immunoregulation of M2 macrophage. A wound healing assay is performed using an S. aureus-infected skin defect model. The application effect of PSNL-1.5 is significantly better than that of a commercial nano‑silver burn &amp; scald dressing (Anson®), revealing huge potential for clinical translation. This study is of significant novelty in demonstrating the antibacterial and pro-regenerative abilities of probiotic biofilms. The product of this study will be extensively used for treating infected wounds or other wounds.}, }
@article {pmid39197623, year = {2024}, author = {Zhou, J and Li, K and Ramasamy, P}, title = {Chitosan-collagen biopolymer biofilm derived from cephalopod gladius; Evaluation of osteogenesis, angiogenesis and wound healing for tissue engineering application.}, journal = {International journal of biological macromolecules}, volume = {279}, number = {Pt 1}, pages = {135078}, doi = {10.1016/j.ijbiomac.2024.135078}, pmid = {39197623}, issn = {1879-0003}, mesh = {Animals ; *Chitosan/chemistry/pharmacology ; *Wound Healing/drug effects ; *Collagen/chemistry/pharmacology/metabolism ; *Osteogenesis/drug effects ; *Neovascularization, Physiologic/drug effects ; Rats ; *Tissue Engineering ; Male ; Rats, Wistar ; Biofilms/drug effects ; Biopolymers/chemistry/pharmacology ; Angiogenesis ; }, abstract = {Chitosan (Ch) and acid-soluble collagen (ASC) from Doryteuthis singhalensis gladius were isolated to test their osteogenic, angiogenic, and wound healing capabilities in male Wistar rats. The results of the study showed that the ASC yield was 18.58 %, the total protein content was 86.43 % ± 0.18 %, and the amino acid composition was as follows: glycine, 15.68 %; proline, 13.84 %. A, B, I, II, and III show FT-IR amide regional bands at 3392, 2959, 1652, 1471, and 1237 cm[-1] respectively. The electrophoretic pattern of ASC validated its molecular weights of 105 kDa and 96 kDa. The [1]H NMR spectra showed pure singles at 1.99 ppm, and the UV-Vis spectrum showed a particular absorbance between 238 and 220 nm. The DSC showed two endothermic peaks: one with an To value of 119.72 °C and TP of 126.28 °C, and the other with 147.42 °C and 148.47 °C. Initially, we fabricated Ch and ASC biofilms at an 8.5:1.5 ratio for tissue engineering applications. A cellular-level study demonstrated good biocompatibility and enhanced osteoblastic differentiation of collagen chitosan films (CChF). Additionally, the biofilm exhibited increased angiogenic potency, as observed in the chick embryo chorioallantoic membrane (CAM) assay. The experimental animal model demonstrated that in wound healing, the CChF treated rats (95.75 ± 2.28 %) had a greater decrease in the diameter of the wound than the control rats (22.25 ± 2.45 %), followed by the CF (collagen film) treated rats (63.25 ± 2.08 %) and ChF (chitosan film) (52.67 ± 1.58 %). Rats treated with CChF had 48.82 ± 1.25 mg/g of hydroxyproline in NFGT and 75.25 ± 1.56 mg/g of overall protein. The higher hydroxyproline levels in the CChF-treated groups corroborated these histopathological findings. These results imply that by promoting the development of scars, inflammation, and proliferation, CChF accelerates the healing process.}, }
@article {pmid39196492, year = {2024}, author = {Ünal, N and Kiymaci, ME and Savluk, M and Erdogan, H and Seker, E}, title = {Determination of antibacterial and anti-biofilm activities of Terpinen-4-ol loaded polydopamine nanoparticles against Staphylococcus aureus isolates from cows with subclinical mastitis.}, journal = {Veterinary research communications}, volume = {48}, number = {6}, pages = {3655-3668}, pmid = {39196492}, issn = {1573-7446}, support = {Project No:221O176//The Scientific and Technological Research Council of T&#xfc;rkiye (TUBITAK)/ ; }, mesh = {Animals ; Cattle ; *Biofilms/drug effects ; *Staphylococcus aureus/drug effects/physiology ; *Anti-Bacterial Agents/pharmacology ; *Indoles/pharmacology/chemistry ; *Polymers/pharmacology/chemistry ; *Nanoparticles/chemistry ; Female ; *Mastitis, Bovine/microbiology ; *Staphylococcal Infections/veterinary/microbiology/drug therapy ; Microbial Sensitivity Tests ; Terpenes/pharmacology/chemistry ; }, abstract = {Mastitis in cows is one of the most important diseases that give rise to economic losses in dairy farms. Increasing antimicrobial resistance in Staphylococcus aureus, one of the most common causes of mastitis, is a significant health problem. Due to the problems encountered in treating infections caused by resistant strains, developing alternative treatment methods, such as Nanomaterial systems and natural agents, are important. The essential oil of Melaleuca alternifolia is used as an antibacterial and the primary active component is terpinen-4-ol. This study aimed to investigate the antibacterial and anti-biofilm activity of terpinen-4-ol and terpinen-4-ol loaded polydopamine (T-PDA) nanoparticles against S. aureus isolates, which were resistant to at least one group of antibiotics isolated from milk samples of subclinical mastitis cows. The S. aureus strains were identified by biochemical tests and verified with the API Staph kit. The antibiotic susceptibility of the isolates was determined by the disc diffusion method. The broth microdilution method determined the antimicrobial activities of the terpinen-4-ol and T-PDA nanoparticles, and anti-biofilm activities were assessed using the modified crystal violet method. All of the isolates were resistant to benzylpenicillin and susceptible to trimethoprim/sulfamethoxazole. Multi-antibiotic resistance was detected in the 11 S. aureus isolates used in this study. For the terpinen-4-ol and T-PDA nanoparticles, MIC values were determined in the range of 0.125-0.5% (µL/mL) and 0.125-0.25% (µL/mL), respectively. None of the isolates formed biofilms. As a result, it was found that the antibacterial efficacy of the T- PDA nanoparticles was higher against nine of the S. aureus isolates than against the terpinen-4-ol.}, }
@article {pmid39195716, year = {2024}, author = {Díaz, LKC and Berná, A and Boltes, K}, title = {Bioelectroremediation of a Real Industrial Wastewater: The Role of Electroactive Biofilm and Planktonic Cells through Enzymatic Activities.}, journal = {Toxics}, volume = {12}, number = {8}, pages = {}, pmid = {39195716}, issn = {2305-6304}, support = {PID2021-128700OB-I00//Ministerio de Ciencia e Innovaci&#xf3;n/ ; P2018/EMT-4341//Comunidad de Madrid/ ; }, abstract = {Bioelectrochemical processes are emerging as one of the most efficient and sustainable technologies for wastewater treatment. Their application for industrial wastewater treatment is still low due to the high toxicity and difficulty of biological treatment for industrial effluents. This is especially relevant in pharmaceutical industries, where different solvents, active pharma ingredients (APIs), extreme pH, and salinity usually form a lethal cocktail for the bacterial community in bioreactors. This work evaluates the impact of the anode architecture on the detoxification performance and analyzes, for the first time, the profile of some key bioremediation enzymes (catalase and esterase) and reactive oxygen species (ROS) during the operation of microbial electrochemical cells treating real pharmaceutical wastewater. Our results show the existence of oxidative stress and loss of cell viability in planktonic cells, while the electrogenic bacteria that form the biofilm maintain their biochemical machinery intact, as observed in the bioelectrochemical response. Monitorization of electrical current flowing in the bioelectrochemical system showed how electroactive biofilm, after a short adaptation period, started to degrade the pharma effluent. The electroactive biofilms are responsible for the detoxification of this type of industrial wastewater.}, }
@article {pmid39195076, year = {2024}, author = {Christian, N and Burden, D and Emam, A and Brenk, A and Sperber, S and Kalu, M and Cuadra, G and Palazzolo, D}, title = {Effects of E-Liquids and Their Aerosols on Biofilm Formation and Growth of Oral Commensal Streptococcal Communities: Effect of Cinnamon and Menthol Flavors.}, journal = {Dentistry journal}, volume = {12}, number = {8}, pages = {}, pmid = {39195076}, issn = {2304-6767}, support = {Not Applicable//Debusk College of Osteopathic Medicine and Muhlenberg College Intramural Funds/ ; }, abstract = {(1) Background: The rise in electronic cigarette (E-cigarette) popularity, especially among adolescents, has prompted research to investigate potential effects on health. Although much research has been carried out on the effect on lung health, the first site exposed to vaping-the oral cavity-has received relatively little attention. The aims of this study were twofold: to examine the effects of E-liquids on the viability and hydrophobicity of oral commensal streptococci, and the effects of E-cigarette-generated aerosols on the biomass and viability of oral commensal streptococci. (2) Methods: Quantitative and confocal biofilm analysis, live-dead staining, and hydrophobicity assays were used to determine the effect on oral commensal streptococci after exposure to E-liquids and/or E-cigarette-generated aerosols. (3) Results: E-liquids and flavors have a bactericidal effect on multispecies oral commensal biofilms and increase the hydrophobicity of oral commensal streptococci. Flavorless and some flavored E-liquid aerosols have a bactericidal effect on oral commensal biofilms while having no effect on overall biomass. (4) Conclusions: These results indicate that E-liquids/E-cigarette-generated aerosols alter the chemical interactions and viability of oral commensal streptococci. Consequently, the use of E-cigarettes has the potential to alter the status of disease and health in the oral cavity and, by extension, affect systemic health.}, }
@article {pmid39193978, year = {2024}, author = {Muslim, SN and Muslem, WH and Alwan, BH and Rasool, KH}, title = {Evaluation of L-Asparaginase Purified from Pseudomonas Fluorescens as Inhibitor for Biofilm Producers in Dental Decays.}, journal = {Clinical laboratory}, volume = {70}, number = {8}, pages = {}, doi = {10.7754/Clin.Lab.2024.240112}, pmid = {39193978}, issn = {1433-6510}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Pseudomonas fluorescens/drug effects/isolation &amp; purification ; *Asparaginase/pharmacology/isolation &amp; purification ; Humans ; *Dental Caries/microbiology ; *Phylogeny ; RNA, Ribosomal, 16S/genetics ; Anti-Bacterial Agents/pharmacology ; }, abstract = {BACKGROUND: This study aimed to assess Pseudomonas fluorescens-purified L-Asparaginase's effectiveness as a broad-spectrum inhibitor of biofilm producers in dental decays.<br><br>METHODS: The 16S rRNA sequence was used to build a phylogenetic tree to calculate the evolutionary distance between the isolated bacterial strain SW3 and other species. The evolutionary history was inferred by using the neighbor-joining approach.<br><br>RESULTS: The bacteria were identified from dental decays, including Staphylococcus aureus, Streptococcus mutans, Streptococcus oralis, and Streptococcus mitis. Each one of these isolates showed different degrees of biofilm development. Purified L-Asparaginase inhibited the most potent Gram-positive biofilm-forming bacteria (biofilm producers) with higher inhibition percentages against Streptococcus oralis and Streptococcus mitis, 65 - 73.8 % and 54.7 - 63%, respectively. The inhibition percentages increased with increasing concentration and reached up to 74 - 81% with Streptococcus oralis and 66 - 74% with Streptococcus mitis, while SW3 bacteria showed (100%). This strain was suggested SW3 (Pseudomonas spp.). Pseudomonas fluorescens bacterial strain isolated from rhizosphere soil produced extracellular L-Asparaginase when grown on as a substrate. L-Asparaginase was purified to homogeneity by using ammonium sulfate at 60% saturation, followed by gel filtration chromatography on a sephadex G-100 column, with a recovery yield of 49% and a purification fold of 2.22.<br><br>CONCLUSIONS: L-Asparaginase had a promising use for removing and avoiding biofilm growth, implying that it might be used in the dental industry in the future.}, }
@article {pmid39193785, year = {2024}, author = {Alves, GDSG and de Oliveira, AMP and Roseno, ACB and Ribeiro, NP and Alves, MDS and Sampaio, C and do Prado, RL and Pessan, JP and Monteiro, DR}, title = {Interkingdom biofilm of Streptococcus pyogenes and Candida albicans: establishment of an in vitro model and dose-response validation of antimicrobials.}, journal = {Biofouling}, volume = {40}, number = {9}, pages = {580-592}, doi = {10.1080/08927014.2024.2395390}, pmid = {39193785}, issn = {1029-2454}, mesh = {*Candida albicans/drug effects/physiology ; *Biofilms/drug effects ; *Streptococcus pyogenes/drug effects/physiology ; Humans ; Dose-Response Relationship, Drug ; Saliva/microbiology ; Microbial Sensitivity Tests ; Culture Media/chemistry ; Amoxicillin/pharmacology ; Nystatin/pharmacology ; Anti-Bacterial Agents/pharmacology ; Anti-Infective Agents/pharmacology ; }, abstract = {Although Streptococcus pyogenes and Candida albicans may colonize tonsillar tissues, the interaction between them in mixed biofilms has been poorly explored. This study established an interkingdom biofilm model of S. pyogenes and C. albicans and verified the dose-response validation of antimicrobials. Biofilms were formed on microplates, in the presence or absence of a conditioning layer of human saliva, using Brain Heart Infusion (BHI) broth or artificial saliva (AS) as a culture medium, and with variations in the microorganism inoculation sequence. Biofilms grown in AS showed higher mass than those grown in BHI broth, and an opposite trend was observed for metabolism. The number of S. pyogenes colonies was lower in AS. Amoxicillin and nystatin showed dose-dependent effects. The inoculation of the two species at the same time, without prior exposure to saliva, and using BHI broth would be the model of choice for future studies assessing the effects of antimicrobials on dual S. pyogenes/C. albicans biofilms.}, }
@article {pmid39193397, year = {2024}, author = {Wang, Z and Lu, X and Zheng, M and Hu, Z and Batstone, D and Yuan, Z and Hu, S}, title = {Quadrupling the capacity of post aerobic digestion treating anaerobically digested sludge using a moving-bed biofilm (MBBR) configuration.}, journal = {Water research X}, volume = {24}, number = {}, pages = {100240}, pmid = {39193397}, issn = {2589-9147}, abstract = {Wastewater treatment plants produce large amounts of sludge requiring stabilization before safe disposal. Traditional biological stabilization approaches are cost-effective but generally require either an extended retention time (10-40 days), or elevated temperatures (40-80 °C) for effective pathogens inactivation. This study overcomes these limitations via a novel acidic aerobic digestion process, leveraging an acid-tolerant ammonia-oxidizing bacterium (AOB) Candidatus Nitrosoglobus. To retain this novel but slowly growing AOB, we proposed the first-ever application of a classical wastewater configuration-moving bed biofilm reactor (MBBR)-for sludge treatment. The AOB in biofilm maintains acidic pH and high nitrite levels in sludge, generating free nitrous acid in situ to expedite sludge stabilization. This process was tested in two laboratory-scale aerobic digesters processing full-scale anaerobically digested sludge. At an ambient temperature of 20 °C, pathogens were reduced to levels well below the threshold specified for the highest stabilization level (Class A), within a retention time of 3.5 days. A high volatile solids reduction of 27.4 ± 5.2% was achieved. Through drastically accelerating stabilization and enhancing reduction, this process substantially saves capital and operational costs for sludge disposal.}, }
@article {pmid39191399, year = {2024}, author = {Ando, K and Miyahara, S and Hanada, S and Fukuda, K and Saito, M and Sakai, A and Maruo, A and Zenke, Y}, title = {Effective biofilm eradication in MRSA isolates with aminoglycoside-modifying enzyme genes using high-concentration and prolonged gentamicin treatment.}, journal = {Microbiology spectrum}, volume = {12}, number = {10}, pages = {e0064724}, pmid = {39191399}, issn = {2165-0497}, support = {21K09241//MEXT | Japan Society for the Promotion of Science (JSPS)/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Gentamicins/pharmacology ; *Methicillin-Resistant Staphylococcus aureus/drug effects/genetics/isolation &amp; purification ; Humans ; *Anti-Bacterial Agents/pharmacology ; *Staphylococcal Infections/microbiology/drug therapy ; *Microbial Sensitivity Tests ; *Aminoglycosides/pharmacology ; Bacterial Proteins/genetics/metabolism ; Drug Resistance, Bacterial/genetics ; Japan ; }, abstract = {UNLABELLED: Bone and soft tissue infections caused by biofilm-forming bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA), remain a significant clinical challenge. While the control of local infection is necessary, systemic treatment is also required, and biofilm eradication is a critical target for successful management. Topical antibiotic treatments, such as antibiotic-loaded bone cement (ALBC), have been used for some time, and continuous local antibiotic perfusion therapy, a less invasive method, has been developed by our group. However, the optimal antibiotics and concentrations for biofilms of clinical isolates are still not well understood. We examined the efficacy of high concentrations of gentamicin against MRSA biofilms and the role of gentamicin resistance genes in biofilm eradication. We collected 101 MRSA samples from a hospital in Japan and analyzed their gene properties, including methicillin and gentamicin resistance, and their minimum biofilm eradication concentration (MBEC) values. Our results showed that high concentrations of gentamicin are effective against MRSA biofilms and that even concentrations lower than the MBEC value could eliminate biofilms after prolonged exposure. We also identified three aminoglycoside/gentamicin resistance genes [aac(6')-aph(2″), aph(3')-III, and ant(4')-IA] and found that the presence or absence of these genes may inform the selection of treatments. It was also found that possession of the aac(6')-aph(2″) gene correlated with the minimum inhibitory concentration/MBEC values of gentamicin. Although this study provides insight into the efficacy of gentamicin against MRSA biofilms and the role of gentamicin resistance genes, careful selection of the optimal treatment strategy is needed for clinical application.<br><br>IMPORTANCE: Our analysis of 101 MRSA clinical isolates has provided valuable insights that could enhance treatment selection for biofilm infections in orthopedics. We found that high concentrations of gentamicin were effective against MRSA biofilms, and even prolonged exposure to concentrations lower than the minimum biofilm eradication concentration (MBEC) value could eliminate biofilms. The presence of the aac(6')-aph(2&#x2033;) gene, an aminoglycoside resistance gene, was found to correlate with the minimum inhibitory concentration (MIC) and MBEC values of gentamicin, providing a potential predictive tool for treatment susceptibility. These results suggest that extended high concentrations of local gentamicin treatment could effectively eliminate MRSA biofilms in orthopedic infections. Furthermore, testing for gentamicin MIC or the possession of the aac(6')-aph(2&#x2033;) gene could help select treatment, including topical gentamicin administration and surgical debridement.}, }
@article {pmid39190939, year = {2024}, author = {Wen, J and Dan, Y and Liu, X and Li, H}, title = {Promoting microalgal biofilm formation by crushed oyster shell-hydroxyapatite layer on micropatterned aluminum coating for heavy metal ions removal.}, journal = {Colloids and surfaces. B, Biointerfaces}, volume = {243}, number = {}, pages = {114168}, doi = {10.1016/j.colsurfb.2024.114168}, pmid = {39190939}, issn = {1873-4367}, mesh = {*Biofilms/drug effects/growth &amp; development ; Animals ; *Aluminum/chemistry/pharmacology ; *Durapatite/chemistry ; *Microalgae/growth &amp; development/drug effects/chemistry ; *Ostreidae/microbiology ; *Metals, Heavy/chemistry/isolation &amp; purification ; Adsorption ; Surface Properties ; Water Pollutants, Chemical/isolation &amp; purification/chemistry ; Chlorella/growth &amp; development/chemistry ; Ions ; Spectroscopy, Fourier Transform Infrared ; }, abstract = {Microalgal biomass has shown inspiring potential for the heavy metal removal from wastewater, and forming microalgal biofilm is one of the sustainable methods for the microalgal biomass production. Here we report the formation of microalgal biofilm by accelerated colonization of typical algae Chlorella on thermal sprayed aluminum (Al) coatings with biologically modified surfaces. Micro-patterning surface treatment of the Al coatings promotes the attachment of Chlorella from 6.31 % to 17.51 %. Further enhanced algae attachment is achieved through liquid flame spraying a bioactive crushed oyster shell-hydroxyapatite (CaCO3-HA) composite top layer on the micropatterned coating, reaching 46.03-49.62 % of Chlorella attachment ratio after soaking in Chlorella suspension for 5 days. The rapidly formed microalgal biofilm shows an adsorption ratio of 95.43 % and 85.23 % for low concentration Zn[2+] and Cu[2+] in artificial seawater respectively within 3 days. Quick interaction has been realized between heavy metal ions and the negatively-charged extracellular polymeric substances (EPS) matrix existing in the biofilm. Fourier transform infrared spectroscopy (FTIR) results indicate that both carboxyl and phosphoryl groups of biofilms are crucial in the adsorption of Cu[2+] and the adsorption of Zn[2+] is due to the hydroxyl and phosphate groups. Meanwhile, the biofilm could act as a barrier to protect Chlorella against the attack of the heavy metal ions with relatively low concentrations in aqueous solution. The route of quick cultivating microalgal biofilm on marine structures through constructing biological layer on their surfaces would give insight into developing new techniques for removing low concentration heavy metal ions from water for environmental bioremediation.}, }
@article {pmid39189769, year = {2024}, author = {Wang, L and Wang, X and Wu, H and Wang, H and Lu, Z}, title = {Interspecies synergistic interactions mediated by cofactor exchange enhance stress tolerance by inducing biofilm formation.}, journal = {mSystems}, volume = {9}, number = {9}, pages = {e0088424}, pmid = {39189769}, issn = {2379-5077}, support = {2022C03001//"Pioneer" and "Leading Goose" R&amp;D Program of Zhejiang/ ; 41721001//MOST | National Natural Science Foundation of China (NSFC)/ ; 32170107//MOST | National Natural Science Foundation of China (NSFC)/ ; }, mesh = {*Biofilms/growth &amp; development ; Vitamin B 12/metabolism ; Microbial Interactions ; Stress, Physiological/physiology ; Osmotic Pressure/physiology ; Bacteria/metabolism/genetics ; S-Adenosylmethionine/metabolism ; }, abstract = {UNLABELLED: Metabolic exchange plays a crucial role in shaping microbial community interactions and functions, including the exchange of small molecules such as cofactors. Cofactors are fundamental to enzyme catalytic activities; however, the role of cofactors in microbial stress tolerance is unclear. Here, we constructed a synergistic consortium containing two strains that could efficiently mineralize di-(2-ethylhexyl) phthalate under hyperosmotic stress. Integration of transcriptomic analysis, metabolic profiling, and a genome-scale metabolic model (GEM) facilitated the discovery of the potential mechanism of microbial interactions. Multi-omics analysis revealed that the vitamin B12-dependent methionine-folate cycle could be a key pathway for enhancing the hyperosmotic stress tolerance of synergistic consortium. Further GEM simulations revealed interspecies exchange of S-adenosyl-L-methionine and riboflavin, cofactors needed for vitamin B12 biosynthesis, which was confirmed by in vitro experiments. Overall, we proposed a new mechanism of bacterial hyperosmotic stress tolerance: bacteria might promote the production of vitamin B12 to enhance biofilm formation, and the species collaborate with each other by exchanging cofactors to improve consortium hyperosmotic stress tolerance. These findings offer new insights into the role of cofactors in microbial interactions and stress tolerance and are potentially exploitable for environmental remediation.<br><br>IMPORTANCE: Metabolic interactions (also known as cross-feeding) are thought to be ubiquitous in microbial communities. Cross-feeding is the basis for many positive interactions (e.g., mutualism) and is a primary driver of microbial community assembly. In this study, a combination of multi-omics analysis and metabolic modeling simulation was used to reveal the metabolic interactions of a synthetic consortium under hyperosmotic stress. Interspecies cofactor exchange was found to promote biofilm formation under hyperosmotic stress. This provides a new perspective for understanding the role of metabolic interactions in microbial communities to enhance environmental adaptation, which is significant for improving the efficiency of production activities and environmental bioremediation.}, }
@article {pmid39188729, year = {2024}, author = {Suban, S and Yemini, S and Shor, A and Waldman Ben-Asher, H and Yaron, O and Karako-Lampert, S and Sendersky, E and Golden, SS and Schwarz, R}, title = {A cyanobacterial sigma factor F controls biofilm-promoting genes through intra- and intercellular pathways.}, journal = {Biofilm}, volume = {8}, number = {}, pages = {100217}, pmid = {39188729}, issn = {2590-2075}, abstract = {Cyanobacteria frequently constitute integral components of microbial communities known as phototrophic biofilms, which are widespread in various environments. Moreover, assemblages of these organisms, which serve as an expression platform, simplify harvesting the biomass, thereby holding significant industrial relevance. Previous studies of the model cyanobacterium Synechococcus elongatus PCC 7942 revealed that its planktonic growth habit results from a biofilm-suppression mechanism that depends on an extracellular inhibitor, an observation that opens the door to investigating cyanobacterial intercellular communication. Here, we demonstrate that the RNA polymerase sigma factor SigF1, is required for this biofilm-suppression mechanism whereas the S. elongatus paralog SigF2 is not involved in biofilm regulation. Comprehensive transcriptome analyses identified distinct regulons under the control of each of these sigma factors. sigF1 inactivation substantially lowers transcription of genes that code for the primary pilus subunit and consequently prevents pilus assembly. Moreover, additional data demonstrate absence of the biofilm inhibitor from conditioned medium of the sigF1 mutant, further validating involvement of the pilus assembly complex in secretion of the biofilm inhibitor. Consequently, expression is significantly upregulated for the ebfG-operon that encodes matrix components and the genes that encode the corresponding secretion system, which are repressed by the biofilm inhibitor in the wild type. Thus, this study uncovers a basic regulatory component of cyanobacterial intercellular communication, a field that is in its infancy. Elevated expression of biofilm-promoting genes in a sigF1 mutant supports an additional layer of regulation by SigF1 that operates via an intracellular mechanism.}, }
@article {pmid39185371, year = {2024}, author = {Mashal, S and Siddiqua, A and Ullah, N and Baloch, R and Khan, M and Hasnain, SZU and Imran Aziz, M and Huseynov, E and Selakovic, D and Rosic, G and Makhkamov, T and Yuldashev, A and Islamov, S and Abdullayeva, N and Khujanazarov, U and Amin, A}, title = {Bioactive plant waste components targeting oral bacterial pathogens as a promising strategy for biofilm eradication.}, journal = {Frontiers in chemistry}, volume = {12}, number = {}, pages = {1406869}, pmid = {39185371}, issn = {2296-2646}, abstract = {The significance of this study lies in its exploration of bioactive plant extracts as a promising avenue for combating oral bacterial pathogens, offering a novel strategy for biofilm eradication that could potentially revolutionize oral health treatments. Oral bacterial infections are common in diabetic patients; however, due to the development of resistance, treatment options are limited. Considering the excellent antimicrobial properties of phenolic compounds, we investigated them against isolated oral pathogens using in silico and in vitro models. We performed antibiogram studies and minimum inhibitory concentration (MIC), antibiofilm, and antiquorum sensing activities covering phenolic compounds. Bacterial strains were isolated from female diabetic patients and identified by using 16S rRNA sequencing as Pseudomonas aeruginosa, Bacillus chungangensis, Bacillus paramycoides, and Paenibacillus dendritiformis. Antibiogram studies confirmed that all strains were resistant to most tested antibiotics except imipenem and ciprofloxacin. Molecular docking analysis revealed the significant interaction of rutin, quercetin, gallic acid, and catechin with transcription regulator genes 1RO5, 4B2O, and 5OE3. All tested molecules followed drug-likeness rules except rutin. The MIC values of the tested compounds varied from 0.0625 to 0.5 mg/mL against clinical isolates. Significant antibiofilm activity was recorded in the case of catechin (73.5% ± 1.6% inhibition against B. paramycoides), cinnamic acid (80.9% ± 1.1% inhibition against P. aeruginosa), and vanillic acid and quercetin (65.5% ± 1.7% and 87.4% ± 1.4% inhibition, respectively, against B. chungangensis) at 0.25-0.125 mg/mL. None of the phenolic compounds presented antiquorum sensing activity. It was, therefore, concluded that polyphenolic compounds may have the potential to be used against oral bacterial biofilms, and further detailed mechanistic investigations should be performed.}, }
@article {pmid39185188, year = {2024}, author = {Walton, B and Abbondante, S and Marshall, ME and Dobruchowska, JM and Alvi, A and Gallagher, LA and Vallikat, N and Zhang, Z and Wozniak, DJ and Yu, EW and Boons, GJ and Pearlman, E and Rietsch, A}, title = {A biofilm-tropic Pseudomonas aeruginosa bacteriophage uses the exopolysaccharide Psl as receptor.}, journal = {bioRxiv : the preprint server for biology}, volume = {}, number = {}, pages = {}, pmid = {39185188}, issn = {2692-8205}, support = {R01 AI145069/AI/NIAID NIH HHS/United States ; R01 AI169865/AI/NIAID NIH HHS/United States ; R01 EY014362/EY/NEI NIH HHS/United States ; }, abstract = {Bacteria in nature can exist in multicellular communities called biofilms. Biofilms also form in the course of many infections. Pseudomonas aeruginosa infections frequently involve biofilms, which contribute materially to the difficulty to treat these infections with antibiotic therapy. Many biofilm-related characteristics are controlled by the second messenger, cyclic-di-GMP, which is upregulated on surface contact. Among these factors is the exopolysaccharide Psl, which is a critically important component of the biofilm matrix. Here we describe the discovery of a P. aeruginosa bacteriophage, which we have called Clew-1, that directly binds to and uses Psl as a receptor. While this phage does not efficiently infect planktonically growing bacteria, it can disrupt P. aeruginosa biofilms and replicate in biofilm bacteria. We further demonstrate that the Clew-1 can reduce the bacterial burden in a mouse model of P. aeruginosa keratitis, which is characterized by the formation of a biofilm on the cornea. Due to its reliance on Psl for infection, Clew-1 does not actually form plaques on wild-type bacteria under standard in vitro conditions. This argues that our standard isolation procedures likely exclude bacteriophage that are adapted to using biofilm markers for infection. Importantly, the manner in which we isolated Clew-1 can be easily extended to other strains of P. aeruginosa and indeed other bacterial species, which will fuel the discovery of other biofilm-tropic bacteriophage and expand their therapeutic use.}, }
@article {pmid39184815, year = {2024}, author = {Green, HD and Van Horn, GT and Williams, T and Eberly, A and Morales, GH and Mann, R and Hauter, IM and Hadjifrangiskou, M and Schmitz, JE}, title = {Intra-strain colony biofilm heterogeneity in uropathogenic Escherichia coli and the effect of the NlpI lipoprotein.}, journal = {Biofilm}, volume = {8}, number = {}, pages = {100214}, pmid = {39184815}, issn = {2590-2075}, support = {P20 DK123967/DK/NIDDK NIH HHS/United States ; R21 AI175788/AI/NIAID NIH HHS/United States ; }, abstract = {Biofilm growth facilitates the interaction of uropathogenic Escherichia coli (UPEC) with the host environment. The extracellular polymeric substances (EPS) of UPEC biofilms are composed prominently of curli amyloid fiber and cellulose polysaccharide. When the organism is propagated as a colony biofilm on agar media, these macromolecules can generate pronounced macroscopic structures. Moreover, curli/cellulose associate tightly with Congo red, generating a characteristic pink-to-red staining pattern when the media is supplemented with this dye. Among different clinical isolates of UPEC, changes in the abundance of curli/cellulose can lead to diverse colony biofilm phenotypes on a strain-by-strain basis. Nevertheless, for any given isolate, these phenotypes are classically homogenous throughout the colony biofilm. Here, we report that a subset of clinical UPEC isolates display heterogenous 'peppermint' colony biofilms, with distinct pale and red subpopulations. Through isolation of these subpopulations and whole genome sequencing, we demonstrate various emergent mutations associated with the phenomenon, including within the gene encoding the outer membrane lipoprotein nlpI. Deletion of nlpI within independent strain-backgrounds increased biofilm rugosity, while its overexpression induced the peppermint phenotype. Upregulation of EPS-associated proteins and transcripts was likewise observed in the absence of nlpI. Overall, these results demonstrate that EPS elaboration in UPEC is impacted by nlpI. More broadly, this phenomenon of intra-strain colony biofilm heterogeneity may be leveraged as a tool to identify additional members within the broad collection of genes that regulate or otherwise affect biofilm formation.}, }
@article {pmid39184814, year = {2024}, author = {Chen, N and Li, Y and Liang, X and Qin, K and Zhang, Y and Wang, J and Wu, Q and Gupta, TB and Ding, Y}, title = {Bacterial extracellular vesicle: A non-negligible component in biofilm life cycle and challenges in biofilm treatments.}, journal = {Biofilm}, volume = {8}, number = {}, pages = {100216}, pmid = {39184814}, issn = {2590-2075}, abstract = {Bacterial biofilms, especially those formed by pathogens, have been increasingly impacting human health. Bacterial extracellular vesicle (bEV), a kind of spherical membranous structure released by bacteria, has not only been reported to be a component of the biofilm matrix but also plays a non-negligible role in the biofilm life cycle. Nevertheless, a comprehensive overview of the bEVs functions in biofilms remains elusive. In this review, we summarize the biogenesis and distinctive features characterizing bEVs, and consolidate the current literature on their functions and proposed mechanisms in the biofilm life cycle. Furthermore, we emphasize the formidable challenges associated with vesicle interference in biofilm treatments. The primary objective of this review is to raise awareness regarding the functions of bEVs in the biofilm life cycle and lay the groundwork for the development of novel therapeutic strategies to control or even eliminate bacterial biofilms.}, }
@article {pmid39184655, year = {2024}, author = {S, MP and John, J and K, P and Prasad, K and Fahad Ismail, TM and Sivakumar, S and Sivakumar, K and Flora, J and Kumar Sivabalan, P and Wase, P}, title = {Biofilm Formation on Denture Base Material Reinforced With a Novel Organic Material.}, journal = {Cureus}, volume = {16}, number = {7}, pages = {e65232}, pmid = {39184655}, issn = {2168-8184}, abstract = {BACKGROUND: Microcrystalline cellulose (MCC) is a novel organic material developed by one of the authors in this study. When MCC was incorporated with conventionally available denture base resin, it demonstrated increased flexural strength and flexural modulus. However, it was speculated that because the material is organic, it can promote the growth of Candida. The purpose of this study is to evaluate the Candida albicans biofilm formation on polymethyl methacrylate (PMMA) denture base resin incorporated with MCC.<br><br>MATERIALS AND METHODS: MCC is an organic material extracted from the oil palm empty fruit bunch (OPEFB). The growth of C. albicans and biofilm formation in three test groups were compared by biofilm assay and imaging techniques like microscopy (by safranin staining) and scanning electron microscopy. The three test groups were comprised of MCC-reinforced PMMA containing OPEFB fibers of 50-micrometer thickness at 5% weight reinforcement, conventionally and commercially available heat cure PMMA, and an empty well to assess any discrepancies from the environment.<br><br>RESULTS: The test groups showed increased biofilm formation by C. albicans compared to commercially and conventionally available heat cure PMMA. Reinforcement with MCC showed higher biofilm formation of 1.43 times higher compared to conventional PMMA. Biofilms formed by Candida albicans on MCC-reinforced PMMA appeared heterogeneous in structure, comprised of yeast cells and hyphae, surrounded by a higher density of polysaccharide extracellular matrix material compared to that of conventionally available heat cure PMMA.<br><br>CONCLUSION: Biofilm formation is increased in denture base resin incorporated with MCC. More investigation is warranted to study the antifungal efficacy of the addition of antifungal agents to the reinforced denture base resin.}, }
@article {pmid39182887, year = {2024}, author = {Ma, W and Yang, Y and Wang, W and Qv, J and Jia, J and Ren, X}, title = {Fabrication of N-halamine/MWPPy-ZnO hybrids based cellulose nanofibril composite films with improved UV-protective, antibacterial, and biofilm control functions.}, journal = {International journal of biological macromolecules}, volume = {278}, number = {Pt 3}, pages = {135023}, doi = {10.1016/j.ijbiomac.2024.135023}, pmid = {39182887}, issn = {1879-0003}, mesh = {*Cellulose/chemistry ; *Zinc Oxide/chemistry/pharmacology ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Ultraviolet Rays ; *Biofilms/drug effects ; *Nanofibers/chemistry ; Amines/chemistry ; Staphylococcus aureus/drug effects ; Spectroscopy, Fourier Transform Infrared ; Microbial Sensitivity Tests ; Escherichia coli/drug effects ; }, abstract = {The design and fabrication of synergistic hybrid antibacterial materials is a promising approach for achieving effective sterilization while compensating for the deficiency of a single component. Despite being highly effective biocidal components, the poor UV light stability of some N-halamines limits their applications. This study was conducted to address this issue by the rational integration of cyclic N-halamine precursor (PGHAPA) with microwaved zinc oxide (MWPPy-ZnO) nanoparticles via covalent bonds and the preparation of cellulose nanofibrils based antibacterial composite films after chlorination (CNF/MWPPy-ZnO-PGHAPA-Cl). The proposed films offered tight lamellar structure, considerable thermal stability and better mechanical properties. The results from the FT-IR and XPS experiments provided the evidence of chemical reactions among the PGHAPA, MWPPy-ZnO, and CNF film. Notably, the CNF/MWPPy-ZnO-PGHAPA-Cl films showed improved UV stability with a chlorine content of up to 0.16 % after 24 h of irradiation, which was much greater than that of the CNF/PGHAPA-Cl films. Furthermore, the CNF/MWPPy-ZnO-PGHAPA-Cl films displayed rapid bactericidal activity, inactivating all the contacted Staphylococcus aureus and Escherichia coli O157:H7 strains within 5 min, along with prominent biofilm disruption, indicating great potential for daily food packaging applications.}, }
@article {pmid39182856, year = {2024}, author = {A, J and Deepa, PM and Vergis, J and Rajasekhar, R and Habeeb, BP and David, PV and Bipin, KC and Anand, LF and Vijayakumar, K}, title = {Green synthesized silver nanoparticles from Ocimum sanctum: A potent inhibitor of biofilm forming ability and efflux pumps in bacteria causing bovine mastitis.}, journal = {Microbial pathogenesis}, volume = {195}, number = {}, pages = {106883}, doi = {10.1016/j.micpath.2024.106883}, pmid = {39182856}, issn = {1096-1208}, mesh = {Animals ; *Biofilms/drug effects ; Cattle ; *Silver/pharmacology/chemistry/metabolism ; *Mastitis, Bovine/microbiology/drug therapy ; *Metal Nanoparticles/chemistry ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; Female ; *Plant Extracts/pharmacology/chemistry ; *Drug Resistance, Multiple, Bacterial/drug effects ; *Ocimum sanctum/chemistry ; *Klebsiella pneumoniae/drug effects/genetics ; Plant Leaves/microbiology ; Escherichia coli/drug effects/genetics ; Green Chemistry Technology ; Staphylococcus/drug effects ; }, abstract = {Therapeutic management of mastitis faces significant challenges due to multidrug resistance. In the present study, multi-drug-resistant (MDR) Staphylococcus spp, Klebsiella pneumoniae, and Escherichia coli were isolated from bovine clinical mastitis cases and the phenotypic and genotypic multidrug resistance profiling was carried out. Silver nanoparticles (AgNPs) were biosynthesized using Ocimum sanctum leaf extracts and characterized via UV Vis absorption, Fourier Transform Infrared Spectroscopy, X-ray diffraction studies, Energy dispersive spectroscopy and Electron Microscopy. The determined minimum inhibitory concentration and minimum bactericidal concentration of the AgNPs against the recovered MDR isolates were 62.5 μg/ml and 125 μg/ml respectively. At a concentration of 50 μg/ml, the AgNPs demonstrated biofilm inhibitory activities of 80.35 % for MDR E. coli, 71.29 % for S. aureus and 60.18 % for MDR K. pneumoniae. Post-treatment observations revealed notable differences in biofilm formation across bacterial isolates. Furthermore, AgNP treatment led to significant downregulation of expression of the efflux pump genes acrB, acrE, acrF, and emrB in Gram-negative isolates and norB in Staphylococci isolates. This research underscores the potential for the development of an eco-friendly antimicrobial alternative in the form of green synthesized silver nanoparticles to combat drug resistance offering potential antibiofilm and efflux pump inhibitory activities.}, }
@article {pmid39182787, year = {2024}, author = {Zheng, X and Zhang, W and Wu, Y and Wu, J and Chen, Y and Long, M}, title = {Biodegradation of organosulfur with extra carbon source: Insights into biofilm formation and bacterial metabolic processes.}, journal = {The Science of the total environment}, volume = {951}, number = {}, pages = {175758}, doi = {10.1016/j.scitotenv.2024.175758}, pmid = {39182787}, issn = {1879-1026}, mesh = {*Biofilms ; *Biodegradation, Environmental ; *Carbon/metabolism ; *Water Pollutants, Chemical/metabolism ; *Bacteria/metabolism ; Bioreactors/microbiology ; Waste Disposal, Fluid/methods ; Sulfur Compounds/metabolism ; Wastewater/microbiology ; Bacterial Physiological Phenomena ; }, abstract = {Organosulfur compounds are prevalent in wastewater, presenting challenges for biodegradation, particularly in low-carbon environments. Supplementing additional carbon sources not only provides essential nutrients for microbial growth but also serves as regulators, influencing adaptive changes in biofilm and enhancing the survival of microorganisms in organosulfur-induced stress bioreactors. This study aims to elucidate the biodegradation of organosulfur under varying carbon source levels, placing specific emphasis on functional bacteria and metabolic processes. It has been observed that higher levels of carbon supplementation led to significantly improved total sulfur (TS) removal efficiencies, exceeding 83 %, and achieve a high organosulfur CH3SH removal efficiency of ~100 %. However, in the reactor with no external carbon source added, the oxidation end-product SO4[2-] accumulated significantly, surpassing 120 mEq/m[2]-day. Furthermore, the TB-EPS concentration consistently increasedwith the ascending glucose concentration. The analysis of bacterial community reveals the enrichment of functional bacteria involved in sulfur metabolism and biofilm formation (e.g. Ferruginibacter, Rhodopeudomonas, Gordonia, and Thiobacillus). Correspondingly, the gene expressions related to the pathway of organosulfur to SO4[2-] were notably enhanced (e.g. MTO increased by 27.7 %). In contrast, extra carbon source facilitated the transfer of organosulfur into amino acids in sulfur metabolism and promoted assimilation. These metabolic insights, coupled with kinetic transformation results, further validate distinct sulfur pathways under different carbon source conditions. The intricate interplay between bacteria growth regulation, pollutant biodegradation, and microbial metabolites underscores a complex network relationship that significantly contributes to efficient operation of bioreactors.}, }
@article {pmid39181904, year = {2024}, author = {Udayagiri, H and Sana, SS and Dogiparthi, LK and Vadde, R and Varma, RS and Koduru, JR and Ghodake, GS and Somala, AR and Boya, VKN and Kim, SC and Karri, RR}, title = {Phytochemical fabrication of ZnO nanoparticles and their antibacterial and anti-biofilm activity.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {19714}, pmid = {39181904}, issn = {2045-2322}, mesh = {*Zinc Oxide/chemistry/pharmacology ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Biofilms/drug effects ; *Metal Nanoparticles/chemistry ; *Escherichia coli/drug effects ; *Microbial Sensitivity Tests ; *Klebsiella pneumoniae/drug effects ; Plant Extracts/chemistry/pharmacology ; Phytochemicals/pharmacology/chemistry ; X-Ray Diffraction ; Spectroscopy, Fourier Transform Infrared ; }, abstract = {The synthesis of metal nanoparticles through bio-reduction is environmentally benign and devoid of impurities, which is very important for biological applications. This method aims to improve ZnO nanoparticle's antibacterial and anti-biofilm activity while reducing the amount of hazardous chemicals used in nanoparticle production. The assembly of zinc oxide nanoparticles (ZnO NPs) is presented via bio-reduction of an aqueous zinc nitrate solution using Echinochloacolona (E. colona) plant aqueous leaf extract comprising various phytochemical components such as phenols, flavonoids, proteins, and sugars. The synthesized nano ZnO NPs are characterized by UV-visible spectrophotometer (UV-vis), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (X-RD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and elemental composition by energy-dispersive x-ray spectroscopy (EDX). The formation of biosynthesized ZnO nanoparticles was confirmed by the absorbance at 360-370 nm in the UV-vis spectrum. The average crystal size of the particles was found to be 15.8 nm, as calculated from XRD. SEM and TEM analysis of prepared ZnO NPs confirmed the spherical and hexagonal shaped nanoparticles. ZnO NPs showed antibacterial activity against Escherichia coli and Klebsiella pneumoniae with the largest zone of inhibition (ZOI) of 17 and 18 mm, respectively, from the disc diffusion method. Furthermore, ZnO NPs exhibited significant anti-biofilm activity in a dose-dependent manner against selected bacterial strains, thus suggesting that ZnO NPs can be deployed in the prevention of infectious diseases and also used in food preservation.}, }
@article {pmid39181514, year = {2024}, author = {Wang, T and Han, X and Cheng, Y and Yang, J and Bai, L and Zeng, W and Wang, H and Cheng, N and Zhang, H and Li, G and Liang, H}, title = {Insights into the azo dye decolourisation and denitrogenation in micro-electrolysis enhanced counter-diffusion biofilm system.}, journal = {Bioresource technology}, volume = {411}, number = {}, pages = {131333}, doi = {10.1016/j.biortech.2024.131333}, pmid = {39181514}, issn = {1873-2976}, mesh = {*Biofilms ; *Electrolysis ; Azo Compounds/metabolism/chemistry ; Coloring Agents/metabolism/chemistry ; Bioreactors ; Diffusion ; Anthraquinones/metabolism ; Nitrogen ; Biodegradation, Environmental ; }, abstract = {In this study, electron transport pathways were activated and diversified by coupling counter-diffusion biofilms with micro-electrolysis for Alizarin yellow R (AYR) denitrogenation. Due to the binding of AYR to two residues of EC 4.1.3.36 with higher binding energy, the expression of EC 4.1.3.36 was down-regulated, causing the EC 3.1.2.28 and EC 2.5.1.74 for menaquinone synthesis (redox mediator) undetectable in Membrane aerated biofilm reactors (MABR). Spontaneous electron generation in the micro electrolysis-coupled MABR (ME-MABR) significantly activated two enzymes. Activated menaquinone up-regulated decolourisation related genes expression in ME-MABR, including azoR (2.12 log2), NQO1 (2.97 log2), wrbA (0.45 log2), and ndh (0.47 log2). The diversified electron flow pathways also promoted the nitrogen metabolism coding genes up-regulation, accelerating further inorganic nitrogen denitrogenation after AYR mineralisation. Compared to MABR, the decolourisation, mineralisation, and denitrogenation in ME-MABR increased by 25.80 %, 16.53 %, and 13.32 %, respectively. This study provides new insights into micro-electrolysis enhanced removal of AYR.}, }
@article {pmid39181432, year = {2024}, author = {Lu, C and Zhang, YY and Peng, SM and Gu, M and Wong, HM}, title = {Effects of graphene oxide and graphene quantum dots on enhancing CPP-ACP anti-caries ability of enamel lesion in a biofilm-challenged environment.}, journal = {Journal of dentistry}, volume = {149}, number = {}, pages = {105319}, doi = {10.1016/j.jdent.2024.105319}, pmid = {39181432}, issn = {1879-176X}, mesh = {*Graphite/chemistry/pharmacology ; *Biofilms/drug effects ; *Caseins/pharmacology ; *Dental Enamel/drug effects ; *Streptococcus mutans/drug effects ; Humans ; *Quantum Dots ; *Dental Caries/microbiology/prevention &amp; control ; Microscopy, Electron, Scanning ; Tooth Remineralization/methods ; Cariostatic Agents/pharmacology/chemistry ; Microscopy, Confocal ; Hydrogen-Ion Concentration ; Citric Acid/pharmacology ; Fibroblasts/drug effects ; Saliva, Artificial/chemistry ; }, abstract = {OBJECTIVE: To investigate the anticaries effects of graphene oxide (GO) and graphene quantum dots (GQDs) combined with casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) on enamel in a biofilm-challenged environment.<br><br>MATERIAL AND METHODS: GO and GQDs were synthesised using citric acid. The antibiofilm and biofilm inhibition effects for Streptococcus mutans were evaluated by scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), and colony-forming units (CFU). Remineralisation ability was determined by assessing mineral loss, calcium-to-phosphorus ratio, and surface morphology. To create a biofilm-challenged environment, enamel blocks were immersed in S. mutans to create the lesion and then subjected to artificial saliva/biofilm cycling for 7 days. Anticaries effects of GO, GQDs, GQDs@CPP-ACP, GO@CPP-ACP, and CPP-ACP were determined by broth pH and mineral changes after 7-day pH cycling. Biocompatibility was tested using a Cell Counting Kit-8 (CCK8) assay for human gingival fibroblasts (HGF-1).<br><br>RESULTS: GQDs and GO presented significant antibiofilm and biofilm inhibition effects compared to the CPP-ACP and control groups (P < 0.05). The enamel covered by GQDs and GO showed better crystal structure formation and less mineral loss (P < 0.05) than that covered by CPP-ACP alone. After 7 days in the biofilm-challenged environment, the GO@CPP-ACP group showed less lesion depth than the CPP-ACP and control groups (P < 0.05). GO and GQDs showed good biocompatibility compared to the control group by CCK8 (P > 0.05) within 3 days.<br><br>CONCLUSION: GO and GQDs could improve the anti-caries effects of CPP-ACP, and CPP-ACP agents with GO or GQDs could be a potential option for enamel lesion management.<br><br>CLINICAL SIGNIFICANCE: GO and GQDs have demonstrated the potential to significantly enhance the anticaries effects of CPP-ACP. Incorporating these nanomaterials into CPP-ACP formulations could provide innovative and effective options for the management of enamel lesions, offering improved preventive and therapeutic strategies in dental care.}, }
@article {pmid39180785, year = {2024}, author = {Aniba, R and Dihmane, A and Raqraq, H and Ressmi, A and Nayme, K and Timinouni, M and Barguigua, A}, title = {Exploring staphylococcus in urinary tract infections: A systematic review and meta-analysis on the epidemiology, antibiotic resistance and biofilm formation.}, journal = {Diagnostic microbiology and infectious disease}, volume = {110}, number = {4}, pages = {116470}, doi = {10.1016/j.diagmicrobio.2024.116470}, pmid = {39180785}, issn = {1879-0070}, mesh = {Humans ; *Anti-Bacterial Agents/pharmacology/therapeutic use ; *Biofilms/drug effects/growth &amp; development ; Drug Resistance, Bacterial ; Microbial Sensitivity Tests ; Prevalence ; *Staphylococcal Infections/drug therapy/epidemiology/microbiology ; *Staphylococcus/drug effects/isolation &amp; purification/physiology ; *Urinary Tract Infections/drug therapy/epidemiology/microbiology ; }, abstract = {This study aimed to determine the epidemiology, biofilm formation and antibiotic resistance of staphylococci collected worldwide in the context of UTIs. This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Forty studies from 23 countries were selected for quantitative review. Electronic databases (PubMed, Scopus, Google Scholar, and Web of Sciences) were searched for articles published between 2010 and 2024 on the epidemiology, biofilm formation, and antibiotic resistance of uropathogenic staphylococci. Strict inclusion and exclusion standards were applied during the review of the articles. Forty articles were included in this systematic review. The prevalence of uropathogenic staphylococci varies from country to country, with the pooled prevalence of S. aureus and coagulase-negative staphylococci (CoNS) being 8.71 % (95 %CI: 6.145-11.69) and 13.17 % (95 %CI: 8.08-19.27) respectively. Among CoNS isolates, S. epidermidis was the most common with 19.3 % (95 %CI: 5.88-38.05). The prevalence of methicillin-resistant S. aureus isolates increased significantly from 23 % in 2010-2015 to 47 % in 2021-2024 (p = 0.03). S. haemolyticus is the most antibiotic-resistant species in CoNS, with 45 % of isolates resistant to methicillin, 33 % to gentamicin, and 29 % to tetracycline. Eighty-eight S. aureus strains were biofilm producers, including 35 % moderate biofilm producers and 48 % strong biofilm producers. The combined frequencies of icaA, clfA and fnbpA were 100, 99, and 89 %, respectively. The development of antibiotic resistance and biofilm formation by staphylococci involved in UTIs explains the need for periodic regional surveillance of these infections, which poses a serious public health problem.}, }
@article {pmid39179305, year = {2024}, author = {Reigh, EL}, title = {STAPH: The Biofilm.}, journal = {Annals of allergy, asthma &amp; immunology : official publication of the American College of Allergy, Asthma, &amp; Immunology}, volume = {133}, number = {3}, pages = {284-285}, doi = {10.1016/j.anai.2024.04.012}, pmid = {39179305}, issn = {1534-4436}, mesh = {*Biofilms ; Humans ; Staphylococcus aureus ; Staphylococcal Infections ; }, }
@article {pmid39178800, year = {2024}, author = {Kuriki, N and Asahi, Y and Okamoto, M and Noiri, Y and Ebisu, S and Machi, H and Suzuki, M and Hayashi, M}, title = {Synergistic effects of arginine and fluoride on human dental biofilm control.}, journal = {Journal of dentistry}, volume = {149}, number = {}, pages = {105307}, pmid = {39178800}, issn = {1879-176X}, support = {K02 DE029531/DE/NIDCR NIH HHS/United States ; R01 DE027648/DE/NIDCR NIH HHS/United States ; }, mesh = {*Arginine/pharmacology ; *Biofilms/drug effects ; Humans ; *Fluorides/pharmacology ; *Toothpastes/pharmacology ; *Cariostatic Agents/pharmacology ; Drug Synergism ; Dentifrices/pharmacology ; Bacterial Load/drug effects ; Bacteria/drug effects/classification ; Microbiota/drug effects ; Dental Plaque/microbiology ; Adult ; Male ; Young Adult ; High-Throughput Nucleotide Sequencing ; Saliva/microbiology ; }, abstract = {OBJECTIVES: The aim of this study was to quantitatively and comprehensively investigate the combined effects of arginine and fluoride on the suppression of pathogenicity using an in situ biofilm model and next-generation sequencing (NGS).<br><br>METHODS: Using the in situ model, dental biofilms were formed and the viable bacterial counts and arginine activity in the arginine- and fluoride-containing dentifrice and control groups were measured. We also compared their effects on the bacterial microbiota and predictive functional factors in the control, arginine (arg), and arginine + fluoride (argF) groups using NGS analysis.<br><br>RESULTS: Compared to the control treatment, the use of 8 % arginine and 1450 ppm fluoride toothpaste resulted in significantly high oral NH4[+] concentrations without affecting the number of viable bacteria (P < 0.05). NGS analysis revealed that the oral microbiota of the control, arg, and argF groups were significantly different. Heat map analysis of the predicted functional factors revealed that the arg group had different properties from the other groups and activated specific substrate metabolic pathways; contrastingly, argF treatment inhibited the activity of these pathways and prevented an increase in the abundance of bacterial genera that utilize substrates such as sucrose, suggesting the synergistic effect of arginine and fluoride.<br><br>CONCLUSIONS: This study indicates that the combination of arginine and fluoride has a synergistic effect on the bacterial microbiota and pathogenicity of dental biofilms compared with arginine alone.<br><br>CLINICAL SIGNIFICANCE: Our findings suggest that the combination of arginine and fluoride could be used as an effective prebiotic and may inhibit the growth of bacteria associated with dental diseases.}, }
@article {pmid39178688, year = {2025}, author = {Jia, D and Zou, Y and Zhang, Y and Xu, H and Yang, W and Zheng, X and Zhang, Y and Yu, Q}, title = {A self-supplied hydrogen peroxide and nitric oxide-generating nanoplatform enhances the efficacy of chemodynamic therapy for biofilm eradication.}, journal = {Journal of colloid and interface science}, volume = {678}, number = {Pt A}, pages = {20-29}, doi = {10.1016/j.jcis.2024.08.148}, pmid = {39178688}, issn = {1095-7103}, mesh = {*Biofilms/drug effects ; *Hydrogen Peroxide/pharmacology/chemistry ; Animals ; *Nitric Oxide/metabolism/chemistry/pharmacology ; Mice ; *Anti-Bacterial Agents/pharmacology/chemistry ; Pseudomonas aeruginosa/drug effects ; Microbial Sensitivity Tests ; Metal-Organic Frameworks/chemistry/pharmacology ; Nanoparticles/chemistry ; Arginine/chemistry/pharmacology ; Copper/chemistry/pharmacology ; Particle Size ; Methicillin-Resistant Staphylococcus aureus/drug effects ; Surface Properties ; Peroxides ; }, abstract = {Bacterial biofilms present a profound challenge to global public health, often resulting in persistent and recurrent infections that resist treatment. Chemodynamic therapy (CDT), leveraging the conversion of hydrogen peroxide (H2O2) to highly reactive hydroxyl radicals (•OH), has shown potential as an antibacterial approach. Nonetheless, CDT struggles to eliminate biofilms due to limited endogenous H2O2 and the protective extracellular polymeric substances (EPS) within biofilms. This study introduces a multifunctional nanoplatform designed to self-supply H2O2 and generate nitric oxide (NO) to overcome these hurdles. The nanoplatform comprises calcium peroxide (CaO2) for sustained H2O2 production, a copper-based metal-organic framework (HKUST-1) encapsulating CaO2, and l-arginine (l-Arg) as a natural NO donor. When exposed to the acidic microenvironment within biofilms, the HKUST-1 layer decomposes, releasing Cu[2+] ions and l-Arg, and exposing the CaO2 core to initiate a cascade of reactions producing reactive species such as H2O2, •OH, and superoxide anions (•O2[-]). Subsequently, H2O2 catalyzes l-Arg to produce NO, which disperses the biofilm and reacts with •O2[-] to form peroxynitrite, synergistically eradicating bacteria with •OH. In vitro assays demonstrated the nanoplatform's remarkable antibiofilm efficacy against both Gram-positive Methicillin-resistant Staphylococcus aureus and Gram-negative Pseudomonas aeruginosa, significantly reducing bacterial viability and EPS content. In vivo mouse model experiments validated the nanoplatform's effectiveness in eliminating biofilms and promoting infected wound healing without adverse effects. This study represents a breakthrough in overcoming traditional CDT limitations by integrating self-supplied H2O2 with NO's biofilm-disrupting capabilities, offering a promising therapeutic strategy for biofilm-associated infection.}, }
@article {pmid39178662, year = {2024}, author = {Her, E and Han, S and Ha, SD}, title = {Development of poly(lactic acid)-based natural antimicrobial film incorporated with caprylic acid against Salmonella biofilm contamination in the meat industry.}, journal = {International journal of food microbiology}, volume = {425}, number = {}, pages = {110871}, doi = {10.1016/j.ijfoodmicro.2024.110871}, pmid = {39178662}, issn = {1879-3460}, mesh = {*Caprylates/pharmacology ; *Biofilms/drug effects/growth &amp; development ; *Food Packaging/methods ; *Polyesters/pharmacology/chemistry ; *Meat/microbiology ; Animals ; *Microbial Sensitivity Tests ; *Salmonella typhimurium/drug effects/growth &amp; development ; Cattle ; Chickens ; Salmonella enteritidis/drug effects/growth &amp; development ; Food Microbiology ; Food Contamination/prevention &amp; control ; Anti-Bacterial Agents/pharmacology ; Anti-Infective Agents/pharmacology ; Salmonella/drug effects/growth &amp; development ; Polymers/pharmacology/chemistry ; Lactic Acid/pharmacology ; }, abstract = {Using a solvent-casting method, a poly(lactic acid) (PLA) film incorporated with caprylic acid (CA) was developed as an active packaging against Salmonella enterica ser. Typhimurium and S. enteritidis to reduce the risk of microbial contamination during distribution and storage of meat. According to the minimum inhibitory concentration (MIC) test results of the natural antimicrobial, CA was introduced at 0.6, 1.2, 2.4, and 4.8 % (v/v) into neat PLA. The biofilm inhibitory effect and antimicrobial efficacy of CA-PLA film against both Salmonella strains, as well as the intermolecular interactions and barrier properties of CA-PLA film, were evaluated. Biofilm formation was reduced to below the detection limit (<1.0 log CFU/cm[2]) for both S. typhimurium and S. enteritidis when co-cultured overnight with 4.8 % CA-PLA film. The 4.8 % CA-PLA film achieved maximum log reductions of 2.58 and 1.65 CFU/g for S. typhimurium and 2.59 and 1.76 CFU/g for S. enteritidis on inoculated chicken breast and beef stored at 25 °C overnight, respectively, without any quality (color and texture) losses. CA maintained its typical chemical structure in the film, as confirmed by attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectra. Furthermore, film surface morphology observations by field emission scanning electron microscopy (FESEM) showed that CA-PLA film was smoother than neat PLA film. No significant (P > 0.05) changes were observed for water vapor permeability and oxygen permeability by the addition of CA into PLA film, suggesting that CA-PLA film is a promising strategy for active packaging to control Salmonella contamination in the meat industry.}, }
@article {pmid39176452, year = {2024}, author = {Berking, BB and Rijpkema, SJ and Zhang, BHE and Sait, A and Amatdjais-Groenen, H and Wilson, DA}, title = {Biofilm Disruption from within: Light-Activated Molecular Drill-Functionalized Polymersomes Bridge the Gap between Membrane Damage and Quorum Sensing-Mediated Cell Death.}, journal = {ACS biomaterials science &amp; engineering}, volume = {10}, number = {9}, pages = {5881-5891}, pmid = {39176452}, issn = {2373-9878}, mesh = {*Biofilms/drug effects ; *Quorum Sensing/drug effects ; *Light ; Polymers/chemistry/pharmacology ; Cell Membrane/metabolism/drug effects ; }, abstract = {Bacterial biofilms represent an escalating global health concern with the proliferation of drug resistance and hospital-acquired infections annually. Numerous strategies are under exploration to combat biofilms and preempt the development of antibacterial resistance. Among these, mechanical disruption of biofilms and enclosed bacteria presents a promising avenue, aiming to induce membrane permeabilization and consequent lethal damage. Herein, we introduce a hemithioindigo (HTI) motor activated by visible light, capable of disrupting sessile bacteria when integrated into a polymeric vesicle carrier. Under visible light, bacteria exhibited a notable outer membrane permeability, reduced membrane fluidity, and diminished viability following mechanical drilling. Moreover, various genetic responses pertaining to the cell envelope were examined via qRT-PCR, alongside the activation of a self-lysis mechanism associated with phage stress, which was coupled with increases in quorum sensing, demonstrating a potential self-lysis cascade from within. The multifaceted mechanisms of action, coupled with the energy efficiency of mechanical damage, underscore the potential of this system in addressing the challenges posed by pathogenic biofilms.}, }
@article {pmid39174958, year = {2024}, author = {Hashim, A and Kheir El Din, NH and El-Khazragy, N and Almalahy, HG}, title = {Comparison of the efficacy of Er,Cr:YSGG laser on oral biofilm removal from implant surfaces with various application times for the treatment of peri-implantitis defects: ex vivo study.}, journal = {BMC oral health}, volume = {24}, number = {1}, pages = {980}, pmid = {39174958}, issn = {1472-6831}, mesh = {Humans ; *Biofilms ; Decontamination/methods ; *Dental Implants/microbiology ; Dental Plaque/microbiology/therapy ; *Lasers, Solid-State/therapeutic use ; *Peri-Implantitis/microbiology/therapy ; Surface Properties ; }, abstract = {PURPOSE: The major struggle in peri-implantitis therapy is the availability of successful decontamination of the infected implant surface. The main hypothesis of this study was the Er,Cr: YSGG laser decontamination efficacy investigation on the infected implant surfaces with various peri-implantitis defects. The primary objective of this study was to decide the efficacy of Er,Cr:YSGG laser as a decontamination tool at various peri-implantitis simulating defects. The secondary objective was to compare the efficacy of the Er,Cr: YSGG laser on oral biofilm removal between two protocols the first protocol (4 cycles at 2.5 min) and the second protocol (5 cycles at 5 min) at various peri-implantitis simulating defects.<br><br>MATERIALS AND METHODS: A total of 3 subjects whose plaque biofilms formed in-vivo on twenty-four tested implants were divided into four tested groups. Two native implants were tested as controls.The in vitro defect model was computer-aided designed and printed into a 3D-printed model with various anulations in peri-implant infrabony defects, which were 15,30,60,and 90 degrees.<br><br>RESULTS: Both Er, Cr: YSGG decontamination protocols at 50&#xa0;mJ (1.5 W/30&#xa0;Hz), 50% air, and 40% water were effective at reducing the total implant surface area/ biofilm ratio (%), but the second protocol had a markedly greater reduction in the duration of application (5 cycles at 5&#xa0;min) than did the first protocol (4 cycles at 2.5&#xa0;min).<br><br>CONCLUSION: The Er, Cr: YSGG laser is an effective decontamination device in various peri-implantitis defects. The second protocol(5 cycles at 5&#xa0;min) with greater application time and circles is more effective than the first one. The defect angulation influence the decontamination capability in peri-implantitis therapy.<br><br>Clinicians anticipate that the exploration of suitable therapeutic modalities for peri-implantitis therapy is limited by the obvious heterogeneity of the available evidence in the literature and need for a pre-clinical theoretical basis setup. The major challenges associated with peri-implantitis therapy include the successful decontamination of the infected implant surface, the absence of any damage to the treated implant surface with adequate surface roughness, and the biocompatibility of the implant surface, which allows osteoblastic cells to grow on the treated surface and is the key for successful re-osseointegration. Therefore, these are the expected empirical triads that need to be respected for successful peri-implantitis therapy. Failure of one of the triads represents a peri-implantitis therapeutic failure. The Er, Cr: YSGG laser is regarded as one of the expected devices for achieving the required triad.<br><br>TRIAL REGISTRATION: "Efficacy of Er,Cr YSGG Laser in Treatment of Peri-implantitis".<br><br>CLINICALTRIALS: gov ID NCT05137821. First Posted date: 30 -11-2021.}, }
@article {pmid39173960, year = {2024}, author = {Hou, Z and Dong, W and Wang, H and Zhao, Z and Li, Y and Liu, H and Shi, K and Liang, Q and Peng, Y}, title = {Rapid start-up of mainstream partial denitrification /anammox and enhanced nitrogen removal through inoculation of precultured biofilm for treating low-strength municipal sewage.}, journal = {Bioresource technology}, volume = {411}, number = {}, pages = {131320}, doi = {10.1016/j.biortech.2024.131320}, pmid = {39173960}, issn = {1873-2976}, mesh = {*Biofilms ; *Denitrification ; *Nitrogen/metabolism ; *Sewage/microbiology ; Bacteria/metabolism ; Bioreactors ; Water Purification/methods ; Anaerobiosis/physiology ; Waste Disposal, Fluid/methods ; Oxidation-Reduction ; }, abstract = {This study investigated the rapid start-up of mainstream partial denitrification coupled with anammox (PD/A) and nitrogen removal performance by inoculating precultured PD/A biofilm. The results showed mainstream PD/A in the anaerobic-anoxic-aerobic (A[2]O) process was rapidly established within 30 days. Nitrogen removal efficiency (NRE) improved by 23.8 % contrasted to the traditional A[2]O process. The mass balance showed that anammox contribution to total nitrogen (TN) removal were maintained at 37.9 %∼55.7 %, and reducing hydraulic retention time (HRT) strengthened simultaneously denitrification and anammox activity. The microbial community showed that the dominant bacteria such as denitrifying bacteria (DNBs) and glycogen accumulating organisms (GAOs) both in biofilm and flocculent sludge (floc), integrating with anammox bacteria (AnAOB) in biofilm might lead to enhanced nitrogen removal. Overall, this study offered a fast start-up strategy of mainstream PD/A with enhanced nitrogen removal, which are valuable for upgradation and renovation of existed municipal wastewater treatment plants (WWTPs).}, }
@article {pmid39173494, year = {2024}, author = {Hemmati, YB and Bahrami, R and Pourhajibagher, M}, title = {Assessing the physico-mechanical, anti-bacterial, and anti-demineralization properties of orthodontic resin composite containing different concentrations of photoactivated zinc oxide nanoparticles on Streptococcus mutans biofilm around ceramic and metal orthodontic brackets: An ex vivo study.}, journal = {International orthodontics}, volume = {22}, number = {4}, pages = {100901}, doi = {10.1016/j.ortho.2024.100901}, pmid = {39173494}, issn = {1879-680X}, mesh = {*Streptococcus mutans/drug effects ; *Orthodontic Brackets ; *Biofilms/drug effects ; *Zinc Oxide/pharmacology ; *Composite Resins/chemistry ; *Ceramics ; *Anti-Bacterial Agents/pharmacology ; Nanoparticles ; Tooth Demineralization/prevention &amp; control ; Shear Strength ; Materials Testing ; Microbial Sensitivity Tests ; Chlorhexidine/pharmacology ; Humans ; Dental Enamel/drug effects ; }, abstract = {BACKGROUND AND PURPOSE: The aim of this study was to evaluate the physico-mechanical, anti-bacterial, and anti-demineralization properties of orthodontic resin composite containing photoactivated zinc oxide nanoparticles (ZnONPs) on Streptococcus mutans biofilm around ceramic and metal brackets.<br><br>MATERIAL AND METHODS: Following the minimum inhibitory concentration (MIC) determination for ZnONPs, shear bond strength (SBS) was tested for composites containing different concentrations of ZnONPs. The chosen concentration was used to evaluate the microleakage, anti-bacterial, and anti-demineralization properties.<br><br>RESULTS: Adding 50&#x3bc;g/mL of ZnONPs to the orthodontic composite did not negatively affect its physico-mechanical properties. ZnONPs (50&#x3bc;g/mL)-mediated aPDT and 0.2% chlorhexidine significantly (P=0.000) reduced S.&#xa0;mutans biofilms compared to the phosphate-buffered saline (PBS) groups (metal/PBS=7.47&#xb1;0.7&#xd7;10[6], and ceramic/PBS=7.47&#xb1;0.7&#xd7;10[6]), with the lowest colony count observed in these groups (metal/chlorhexidine=1.06&#xb1;0.4&#xd7;10[5], ceramic/chlorhexidine=1&#xb1;0.2&#xd7;10[5], metal/ZnONPs-mediated aPDT=1.33&#xb1;0.3&#xd7;10[5], and ceramic/ZnONPs-mediated aPDT=1.2&#xb1;0.3&#xd7;10[5]). Sodium fluoride varnish and ZnONPs-mediated aPDT showed the highest efficacy in anti-demineralization and significantly improving the enamel surface microhardness compared to the artificial saliva, especially in ceramic bracket groups (524.17&#xb1;42.78N and 441.00&#xb1;29.48N, 394.17&#xb1;46.83N, P=0.000, and P=0.003, respectively).<br><br>CONCLUSION: ZnONPs (50&#x3bc;g/mL)-mediated aPDT effectively inhibited S.&#xa0;mutans biofilm and promoted anti-demineralization without adverse effects on the physico-mechanical properties of the composite resin. These results suggest the potential of this method in preventing white spot lesions during orthodontic treatment.}, }
@article {pmid39170400, year = {2024}, author = {Rossetti, AP and Perpetuini, G and Tofalo, R}, title = {Sniffing the wine differences: The role of Starmerella bacillaris biofilm-detached cells.}, journal = {Heliyon}, volume = {10}, number = {15}, pages = {e35692}, pmid = {39170400}, issn = {2405-8440}, abstract = {This study investigated the impact of 10 strains of Starmerella bacillaris, co-inoculated as planktonic or biofilm-detached cells with Saccharomyces cerevisiae, on the volatilome of a red wine. The wines produced with St. bacillaris biofilm-detached cells exhibited a greater concentration of glycerol and a lower quantity of ethanol than the other wines. Furthermore, these wines exhibited elevated levels of higher alcohols, organic acids, esters, terpenes, and norisoprenoids. Based on the odor activity value and relative odor contribution, isoamyl acetate, ethyl octanoate, ethyl isobutanoate, and methyl decanoate were the main aroma components of wines made with planktonic cells. The main compounds characterizing the wines obtained with biofilm-detached cells were: phenethyl alcohol, β-damascenone, citronellol, β-ionone, and nerol. The sensory analysis revealed that the wines produced with biofilm-detached cells had higher scores for mouth-feel, spicy, floral, and raspberry notes than the others. The present study provides evidence that St. bacillaris biofilm-detached cells released specific volatile compounds in red wines.}, }
@article {pmid39169973, year = {2024}, author = {Sultan, AM and Mahmoud, NM}, title = {Detection of resistance integrons among biofilm and non-biofilm producing clinical isolates of Pseudomonas aeruginosa.}, journal = {Germs}, volume = {14}, number = {1}, pages = {11-19}, pmid = {39169973}, issn = {2248-2997}, abstract = {INTRODUCTION: Integrons are genetic systems that may confer antibiotic resistance to Pseudomonas aeruginosa. Biofilm formation can facilitate gene exchange and can accelerate the development of antibiotic resistance. The aim of this work was to assess the distribution of resistance integrons including class 1, 2 and 3 among biofilm- and non-biofilm producing clinical strains of P. aeruginosa. We also aimed to investigate the relationship between the existence of these integrons and the isolates' resistance patterns.<br><br>METHODS: Specimens were obtained from patients showing evidence of infection. P. aeruginosa isolates were identified using conventional techniques, while disk diffusion test was used to detect their antimicrobial susceptibilities. Biofilm formation was detected by the tissue culture plate technique, while classes of integrons were detected by polymerase chain reaction.<br><br>RESULTS: Out of 106 P. aeruginosa isolates, 55.7% were class 1 integron-positive while 19.8% were class 2 integron-positive. However, class 3 integrons were not detected. Significant associations were found between class 1 integrons and resistance toward amikacin, gentamicin, cefepime, ceftazidime and ciprofloxacin. Class 2 integrons were associated with amikacin, ceftazidime and cefepime resistance. Of pseudomonal isolates, 61.3% were biofilm producing. Biofilm production was associated significantly with the existence of class 1 integrons (p<0.001) and class 2 integrons (p=0.039).<br><br>CONCLUSIONS: About two thirds of isolated strains harbored resistance integrons, which emphasized their significance in our locality. The frequencies of class 1 and 2 integrons were significantly higher among biofilm forming isolates. Ongoing surveillance and infection control strategies are necessary to limit spread of integrons.}, }
@article {pmid39169088, year = {2024}, author = {Zacher, AT and Mirza, K and Thieme, L and Nietzsche, S and Senft, C and Schwarz, F}, title = {Biofilm formation of Staphylococcus aureus on various implants used for surgical treatment of destructive spondylodiscitis.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {19364}, pmid = {39169088}, issn = {2045-2322}, mesh = {*Biofilms/growth &amp; development ; *Staphylococcus aureus/physiology/drug effects ; Humans ; *Discitis/microbiology/surgery ; *Titanium ; *Prostheses and Implants/microbiology ; Staphylococcal Infections/microbiology ; Polymers/chemistry ; Anti-Bacterial Agents/pharmacology/therapeutic use ; Bacterial Adhesion ; Bone Cements ; Benzophenones ; Polyethylene Glycols/chemistry ; Ketones ; }, abstract = {The incidence of spondylodiscitis has witnessed a significant increase in recent decades. Surgical intervention becomes necessary in case of bone destruction to remove infected tissue and restore spinal stability, often involving the implantation of a cage. Despite appropriate treatment, relapses occur in up to 20 percent of cases, resulting in substantial economic and social burdens. The formation of biofilm has been identified as a major contributor to relapse development. Currently, there is no consensus among German-speaking spinal surgeons or in the existing literature regarding the preferred choice of material to minimize relapse rates. Thus, the objective of this study is to investigate whether certain materials used in spinal implants exhibit varying degrees of susceptibility to bacterial attachment, thereby providing valuable insights for improving treatment outcomes.Eight cages of each PEEK, titanium-coated PEEK (Ti-PEEK), titanium (Ti), polyetherketoneketone (PEKK), tantalum (Ta) and antibiotic-loaded bone cement were incubated with 20% human plasma for 24 h. Subsequently, four implants were incubated with S. aureus for 24 h or 48 h each. The biofilm was then removed by sonication and the attained solution plated for Colony Forming Units (CFU) counting. Scanning electron microscopy was used to confirm bacterial attachment. The CFUs have been compared directly and in relation to the cages surface area. The surface area of the implants was PEEK 557 mm[2], Ti-PEEK 472 mm[2], Ti 985 mm[2], PEKK 594 mm[2], Ta 706 mm[2], bone cement 123 mm[2]. The mean CFU count per implant and per mm[2] surface area after 24 h and after 48 h was calculated. Bone cement was found to have significantly more CFUs per mm[2] surface area than the other materials tested. When comparing the CFU count per implant, bone cement was statistically significantly more prone to biofilm formation than PEEK after 48 h. There was no statistical significance between the other materials when comparing both CFU count per mm[2] surface area and CFU count per implant. The electron microscopic analysis showed the attachment of the bacteria, as well as production of extracellular polymeric substances (EPS) as a sign for beginning biofilm formation. Antibiotic-loaded bone cement has shown statistically significantly more bacterial attachment than the other examined materials. No difference was found between the other materials regarding bacterial attachment after 24 h and 48 h. Proposed hypotheses for further studies include testing whether differences become apparent after longer incubation or with different pathogens involved in the pathogenesis of pyogenic spondylodiscitis.}, }
@article {pmid39168903, year = {2024}, author = {Evangeline, WP and Rajalakshmi, E and Mahalakshmi, S and Ramya, V and Devkiran, B and Saranya, E and Ramya, M}, title = {Impact of eugenol on biofilm development in Shigella flexneri 1457: a plant terpenoid based-approach to inhibit food-borne pathogen.}, journal = {Archives of microbiology}, volume = {206}, number = {9}, pages = {384}, pmid = {39168903}, issn = {1432-072X}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Shigella flexneri/drug effects/genetics/growth &amp; development/physiology ; *Eugenol/pharmacology ; *Anti-Bacterial Agents/pharmacology ; Quorum Sensing/drug effects ; Microbial Sensitivity Tests ; Dysentery, Bacillary/drug therapy/microbiology ; Terpenes/pharmacology ; }, abstract = {Shigella flexneri is a gram-negative bacterium responsible for shigellosis and bacterial dysentery. Despite using various synthetic antimicrobial agents and antibiotics, their efficacy is limited, prompting concerns over antibiotic resistance and associated health risks. This study investigated eugenol, a polyphenol with inherent antioxidant and antibacterial properties, as a potential alternative treatment. We aimed to evaluate eugenol's antibacterial effects and mechanisms of action against S. flexneri and its impact on biofilm formation. We observed significant growth suppression of S. flexneri with eugenol concentrations of 8-10 mM (98.29%). Quantitative analysis using the Crystal Violet assay demonstrated a marked reduction in biofilm formation at 10 mM (97.01 %). Assessment of Cell Viability and morphology via Fluorescence-Activated Cell Sorting and Scanning Electron Microscopy confirmed these findings. Additionally, qPCR analysis revealed the downregulation of key genes responsible for adhesion (yebL), quorum sensing (rcsC, sdiA), and EPS production (s0482) associated with bacterial growth and biofilm formation. The present study suggests eugenol could offer a promising alternative to conventional antibiotics for treating shigellosis caused by S. flexneri.}, }
@article {pmid39168436, year = {2024}, author = {Qi, R and Qian, C and Li, Y and Wang, Y}, title = {Biofilm formation on MgFe-LDH@quartz sand as novel wetland substrate under varied C/N ratios for BDE-47 removal.}, journal = {Environmental pollution (Barking, Essex : 1987)}, volume = {361}, number = {}, pages = {124779}, doi = {10.1016/j.envpol.2024.124779}, pmid = {39168436}, issn = {1873-6424}, mesh = {*Biofilms ; *Halogenated Diphenyl Ethers ; *Water Pollutants, Chemical/metabolism ; *Wetlands ; Wastewater/chemistry ; Adsorption ; Sand/chemistry ; Waste Disposal, Fluid/methods ; Carbon/chemistry ; Hydroxides/chemistry ; Nitrogen ; }, abstract = {Layered double hydroxide (LDH)-coated substrates could enhance the removal of various wastewater-born pollutants. However, research on biofilms attached to LDH-coatings and their synergistic purification effects on strongly hydrophobic persistent organic pollutants (POPs) remains limited. This study aims to investigate biofilm formation on MgFe-LDH@quartz sand and its effectiveness in removing tetrabromodiphenyl ether (BDE-47), an emerging halogenated POP in municipal wastewater. Under different C/N ratios (3, 5, and 10), BDE-47 removal rates ranged from 28.0% to 41.6% after 72 h. The optimal performance was achieved with LDH coating at C/N = 5, when substrate biofilm reached its highest extracelluar polymer substances (EPS) content, dehydrogenase activity and relative hydrophobicity. Moreover, distinct distribution patterns of EPS components' fluorescence peaks were observed in the LDH-coating treatment using three dimensional excitation-emission matrix (3D-EEM). While substrate adsorption was the primary mechanism for BDE-47 removal, accounting for 59.6%-83.4% of the total, biofilm adsorption and degradation contributed a relatively lower amount, ranging from 11.5% to 21.4%, and were more dependent on the C/N ratio. Notably, the maximum carrying capacity of protein predicted by the logistic growth model exhibited a strong positive correlation with the total BDE-47 removal rate (R[2] = 0.82, p < 0.05), highlighting the importance of biofilm extracelluar proteins.}, }
@article {pmid39167960, year = {2024}, author = {Nasu, T and Maeda, S}, title = {Escherichia coli persisters in biofilm can perform horizontal gene transfer by transformation.}, journal = {Biochemical and biophysical research communications}, volume = {738}, number = {}, pages = {150549}, doi = {10.1016/j.bbrc.2024.150549}, pmid = {39167960}, issn = {1090-2104}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Escherichia coli/genetics/drug effects ; *Gene Transfer, Horizontal ; *Plasmids/genetics ; *Transformation, Bacterial ; Ampicillin/pharmacology ; Anti-Bacterial Agents/pharmacology ; Drug Resistance, Bacterial/genetics/drug effects ; }, abstract = {Persisters represent a subset of cells that exhibit transient tolerance to antimicrobials. These persisters can withstand sudden exposure to antimicrobials, even as the majority of normal cells perish. In this study, we have demonstrated the capacity of ampicillin-tolerant and alkali-tolerant persisters to execute horizontal gene transfer via in situ transformation within biofilms. Air-solid biofilms, comprising two Escherichia coli populations each with a distinct plasmid, were formed on agar media. They were treated with lethal doses of ampicillin or NaOH for 24 h, followed by a 1-min glass-ball roll. This process led to a high frequency of horizontal plasmid transfer (10[-7]-10[-6] per cell) from dead cells to surviving persisters within the biofilms. Plasmid transfer was DNase-sensitive and also occurred by adding purified plasmid DNA to plasmid-free biofilms, demonstrating a transformation mechanism. This marks the first evidence of persisters' novel ability for horizontal gene transfer, via transformation.}, }
@article {pmid39166876, year = {2024}, author = {de Palma, TH and Powers, C and McPartland, MJ and Mark Welch, J and Ramsey, M}, title = {Essential genes for Haemophilus parainfluenzae survival and biofilm growth.}, journal = {mSystems}, volume = {9}, number = {9}, pages = {e0067424}, pmid = {39166876}, issn = {2379-5077}, support = {R01 DE027958/DE/NIDCR NIH HHS/United States ; 1017848//U.S. Department of Agriculture (USDA)/ ; R01DE027958//HHS | NIH | National Institute of Dental and Craniofacial Research (NIDCR)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Haemophilus parainfluenzae/genetics ; *Genes, Essential/genetics ; Humans ; Genome, Bacterial/genetics ; DNA Transposable Elements/genetics ; Microbial Viability/genetics ; }, abstract = {Haemophilus parainfluenzae (Hp) is a Gram-negative, highly prevalent, and abundant commensal in the human oral cavity, and an infrequent extraoral opportunistic pathogen. Hp occupies multiple niches in the oral cavity, including the supragingival plaque biofilm. Little is known about how Hp interacts with its neighbors in healthy biofilms nor its mechanisms of pathogenesis as an opportunistic pathogen. To address this, we identified the essential genome and conditionally essential genes in in vitro biofilms aerobically and anaerobically. Using transposon insertion sequencing (TnSeq) with a highly saturated mariner transposon library in two strains, the ATCC33392 type-strain (Hp 392) and oral isolate EL1 (Hp EL1), we show that the essential genomes of Hp 392 and Hp EL1 are composed of 395 (20%) and 384 (19%) genes, respectively. The core essential genome, consisting of 341 (17%) essential genes conserved between both strains, was composed of genes associated with genetic information processing, carbohydrate, protein, and energy metabolism. We also identified conditionally essential genes for aerobic and anaerobic biofilm growth, which were associated with carbohydrate and energy metabolism in both strains. RNAseq analysis determined that most genes upregulated during anaerobic growth are not essential for Hp 392 anaerobic survival. The completion of this library and analysis under these conditions gives us a foundational insight into the basic biology of H. parainfluenzae in differing oxygen conditions, similar to its in vivo habitat. This library presents a valuable tool for investigation into conditionally essential genes for an organism that lives in close contact with many microbial species in the human oral habitat.IMPORTANCEHaemophilus parainfluenzae is a highly abundant human commensal microbe, present in most healthy individuals where it colonizes the mouth. H. parainfluenzae correlates with good oral health and may play a role in preservation of healthy host status. Also, H. parainfluenzae can cause opportunistic infections outside of the oral cavity. To date, little is known about how H. parainfluenzae colonizes the human host, despite being such a frequent and abundant part of our human microbiome. Here, we demonstrate the creation and use of a powerful tool, a TnSeq library, used to identify genes necessary for both the outright growth of this organism and also genes conditionally essential for growth in varying oxygen status which it can encounter in the human host. This tool and these data serve as a foundation for further study of this relatively unknown organism that may play a role in preserving human health.}, }
@article {pmid39166556, year = {2024}, author = {Casarin, RCV and Silva, RVCD and Paz, HES and Stolf, CS and Carvalho, LM and Noronha, MF and Sallum, AW and Monteiro, MF}, title = {Metatranscriptomic analysis shows functional alterations in subgingival biofilm in young smokers with periodontitis: a pilot study.}, journal = {Journal of applied oral science : revista FOB}, volume = {32}, number = {}, pages = {e20240031}, pmid = {39166556}, issn = {1678-7765}, mesh = {Humans ; *Biofilms ; Pilot Projects ; Male ; Female ; Adult ; *Smoking/adverse effects ; Periodontitis/microbiology ; Case-Control Studies ; Young Adult ; Gene Expression Profiling ; Gingiva/microbiology ; Transcriptome ; }, abstract = {OBJECTIVE: This study aimed to assess the influence of smoking on the subgingival metatranscriptomic profile of young patients affected by stage III/IV and generalized periodontal disease.<br><br>METHODOLOGY: In total, six young patients, both smokers and non-smokers (n=3/group), who were affected by periodontitis were chosen. The STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guidelines for case-control reporting were followed. Periodontal clinical measurements and subgingival biofilm samples were collected. RNA was extracted from the biofilm and sequenced via Illumina HiSeq. Differential expression analysis used Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment, and differentially expressed genes were identified using the Sleuth package in R, with a statistical cutoff of &#x2264;0.05.<br><br>RESULTS: This study found 3351 KEGGs in the subgingival biofilm of both groups. Smoking habits altered the functional behavior of subgingival biofilm, resulting in 304 differentially expressed KEGGs between groups. Moreover, seven pathways were modulated: glycan degradation, galactose metabolism, glycosaminoglycan degradation, oxidative phosphorylation, peptidoglycan biosynthesis, butanoate metabolism, and glycosphingolipid biosynthesis. Smoking also altered antibiotic resistance gene levels in subgingival biofilm by significantly overexpressing genes related to beta-lactamase, permeability, antibiotic efflux pumps, and antibiotic-resistant synthetases.<br><br>CONCLUSION: Due to the limitations of a small sample size, our data suggest that smoking may influence the functional behavior of subgingival biofilm, modifying pathways that negatively impact the behavior of subgingival biofilm, which may lead to a more virulent community.}, }
@article {pmid39165955, year = {2024}, author = {Malekahmadi, S and Yousefnezhadazizi, A and Askaripour, H}, title = {Simulation of anaerobic biodegradation process in a tubular bioreactor with a biofilm layer: Steady-state and unsteady-state conditions.}, journal = {Heliyon}, volume = {10}, number = {15}, pages = {e35397}, pmid = {39165955}, issn = {2405-8440}, abstract = {In this paper, anaerobic biodegradation process in a tubular bioreactor with an inner biofilm layer for steady-state and unsteady-state conditions are simulated. The effects of various parameters including bioreactor diameter, fraction of active biomass transferred to liquid phase, and residence time of the liquid on bioreactor performance are examined. Simulations indicate that decreasing diameter of bioreactor leads to increasing degree of conversion of the substrate in liquid phase and decreasing dimensionless concentration of the substrate in biofilm. With an increase in the fraction of active biomass transferred to liquid, substrate concentrations in liquid and biofilm slightly vary. Increased residence time of the liquid phase results in the degree of conversion of substrate goes up, but substrate concentration in biofilm lowers a little. In addition, it is found that biomass concentration of liquid phase is boosted with decreased bioreactor diameter and increased residence time of liquid. A proportional-integral controller is designed and the tuned parameters of K P = - 0.131 and K I = 0.02 are obtained using genetic algorithm. It is observed that controller regulate well the degree of conversion of the substrate within 120 s for both servo and regulatory modes.}, }
@article {pmid39162860, year = {2024}, author = {Wang, D and Liu, N and Qiao, M and Xu, C}, title = {Gallic acid as biofilm inhibitor can improve transformation efficiency of Ruminiclostridium papyrosolvens.}, journal = {Biotechnology letters}, volume = {46}, number = {6}, pages = {1143-1153}, pmid = {39162860}, issn = {1573-6776}, support = {LZ24C010001//Zhejiang Provincial Natural Science Foundation of China/ ; 32170053//National Natural Science Foundation of China/ ; 2022LFR065//Science Development Foundation of Zhejiang A&amp;F University/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Gallic Acid/pharmacology/metabolism ; Clostridiales/metabolism/genetics ; Transformation, Bacterial ; Metabolic Engineering/methods ; }, abstract = {Ruminiclostridium papyrosolvens is an anaerobic, mesophilic, and cellulolytic clostridia, promising consolidated bioprocessing (CBP) candidate for producing renewable green chemicals from cellulose, but its genetic transformation has been severely impeded by extracellular biofilm. Here, we analyzed the effects of five different inhibitors with gradient concentrations on R. papyrosolvens growth and biofilm formation. Gallic acid was proved to be a potent inhibitor of biofilm synthesis of R. papyrosolvens. Furthermore, the transformation efficiency of R. papyrosolvens was significantly increased when the cells were treated by the gallic acid, and the mutant strain was successfully obtained by the improved transformation method. Thus, inhibition of biofilm formation of R. papyrosolvens by using gallic acid will contribute to its genetic transformation and efficient metabolic engineering.}, }
@article {pmid39162544, year = {2024}, author = {Chen, KZM and Vu, LM and Vollmer, AC}, title = {Cultivation in long-term simulated microgravity is detrimental to pyocyanin production and subsequent biofilm formation ability of Pseudomonas aeruginosa.}, journal = {Microbiology spectrum}, volume = {12}, number = {10}, pages = {e0021124}, pmid = {39162544}, issn = {2165-0497}, mesh = {*Pseudomonas aeruginosa/genetics/physiology/metabolism/growth &amp; development ; *Biofilms/growth &amp; development ; *Pyocyanine/metabolism/biosynthesis ; Weightlessness ; Weightlessness Simulation ; Virulence ; Bioreactors/microbiology ; Bacterial Proteins/genetics/metabolism ; Humans ; }, abstract = {UNLABELLED: Pseudomonas aeruginosa forms aggregates known as biofilms. Previous studies have shown that when P. aeruginosa is cultivated in space, thicker and structurally different biofilms are formed than from those grown on Earth. We investigated how microgravity, simulated in a laboratory setting, influenced the growth, colonization, and virulence potentials of a P. aeruginosa PA14 wild-type strain, as well as two surface attachment-defective (sad) mutants altered at crucial biofilm-forming steps: flgK and pelA. Using high-aspect ratio rotating-wall vessel (HARV) bioreactors, P. aeruginosa bacteria were grown to stationary phase under prolonged (6 days) exposure to simulated microgravity or normal gravity conditions. After the exposure, the capacity of the culture to form biofilms was measured. Additionally, pigment (pyocyanin) formed by each culture during the incubation was extracted and quantified. We demonstrate that the first prolonged exposure to low-shear modeled microgravity (LSMMG) and without nutrient replenishment significantly diminishes wild-type P. aeruginosa PA14 biofilm formation abilities after exposure and pyocyanin production during exposure, while the mutant strains exhibit differing outcomes for both properties.<br><br>IMPORTANCE: Given plans for humans to engage in prolonged space travel, we investigated biofilm and pigment/virulence factor formation in Pseudomonas aeruginosa when cultivated in microgravity. These bacteria are opportunistic pathogens in immunocompromised individuals. Previous studies of space travelers have shown some immune system diminutions. Hence, our studies shed some light on how prolonged cultivation of bacteria in simulated microgravity conditions affect their growth characteristics.}, }
@article {pmid39162533, year = {2024}, author = {Liu, H and Chen, H and Ma, Z and Zhang, Y and Zhang, S and Zhao, D and Yao, Z and Zhou, T and Wang, Z}, title = {Plumbagin enhances antimicrobial and anti-biofilm capacities of chlorhexidine against clinical Klebsiella pneumoniae while reducing resistance mutations.}, journal = {Microbiology spectrum}, volume = {12}, number = {10}, pages = {e0089624}, pmid = {39162533}, issn = {2165-0497}, support = {2022E10022//Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province/ ; no. 2023RC046//The Health Department of Zhejiang Province of the People's Republic of China/ ; }, mesh = {*Biofilms/drug effects ; *Klebsiella pneumoniae/drug effects/genetics ; *Chlorhexidine/pharmacology ; *Naphthoquinones/pharmacology ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology ; *Drug Resistance, Bacterial/genetics ; Humans ; Mutation ; Klebsiella Infections/drug therapy/microbiology ; Drug Synergism ; Bacterial Proteins/genetics/metabolism ; }, abstract = {With the widespread misuse of disinfectants, the clinical susceptibility of Klebsiella pneumoniae (K. pneumoniae) to chlorhexidine (CHX) has gradually diminished, posing significant challenges to clinical disinfection and infection control. K. pneumoniae employs overexpression of efflux pumps and the formation of thick biofilms to evade the lethal effects of CHX. Plumbagin (PLU) is a natural plant extract that enhances membrane permeability and reduces proton motive force. In this study, we elucidated the synergistic antimicrobial activity of PLU in combination with CHX, effectively reducing the MIC of CHX against K. pneumoniae to 1 µg/mL and below. Crucially, through crystal violet staining and confocal laser scanning microscopy live/dead staining, we discovered that PLU significantly enhances the anti-biofilm capability of CHX. Mechanistically, experiments involving membrane permeability, alkaline phosphatase leakage, reactive oxygen species, and RT-qPCR suggest that the combination of PLU and CHX improves the permeability of bacterial inner and outer membranes, promotes bacterial oxidative stress, and inhibits oqxA/B efflux pump expression. Furthermore, we conducted surface disinfection experiments on medical instruments to simulate clinical environments, demonstrating that the combination effectively reduces bacterial loads by more than 3 log10 CFU/mL. Additionally, results from resistance mutation frequency experiments indicate that combined treatment reduces the generation of resistant mutants within the bacterial population. In summary, PLU can serve as an adjuvant, enhancing the anti-biofilm capability of CHX and reducing the occurrence of resistance mutations, thereby extending the lifespan of CHX.IMPORTANCEAs disinfectants are extensively and excessively utilized worldwide, clinical pathogens are progressively acquiring resistance against these substances. However, high concentrations of disinfectants can lead to cross-resistance to antibiotics, and concurrent use of different disinfectants can promote bacterial resistance mutations and facilitate the horizontal transfer of resistance genes, which poses significant challenges for clinical treatment. Compared with the lengthy process of developing new disinfectants, enhancing the effectiveness of existing disinfectants with natural plant extracts is important and meaningful. CHX is particularly common and widely used compared with other disinfectants. Meanwhile, Klebsiella pneumoniae, as a clinically significant pathogen, exhibits high rates of resistance and pathogenicity. Previous studies and our data indicate a significant decrease in the sensitivity of clinical K. pneumoniae to CHX, highlighting the urgent need for novel strategies to address this issue. In light of this, our research is meaningful.}, }
@article {pmid39160249, year = {2024}, author = {Ahmady-Asbchin, S and Akbari Nasab, M and Gerente, C}, title = {Heavy metals biosorption in unary, binary, and ternary systems onto bacteria in a moving bed biofilm reactor.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {19168}, pmid = {39160249}, issn = {2045-2322}, mesh = {*Metals, Heavy/metabolism ; *Bioreactors/microbiology ; *Biofilms/growth &amp; development ; Biodegradation, Environmental ; Nickel/metabolism/chemistry ; Cadmium/metabolism ; Bacillus/metabolism ; Phylogeny ; Hydrogen-Ion Concentration ; Bacteria/metabolism ; Adsorption ; Lead/metabolism ; Temperature ; }, abstract = {Toxic and heavy metals cause direct and indirect damage to the environment and ultimately to humans. This study involved the isolation of indigenous bacteria from heavy metal-contaminated environments that have the ability to bioabsorb heavy metals such as cadmium, nickel, and lead. The bioabsorption process was optimized by varying parameters such as temperature, metal concentration, number of bacteria, pH, and more. The bacterial isolates were investigated in terms of morphology, biochemistry, and phylogeny, with 12 strains chosen in the initial stage and one strain chosen in the final stage. It should be remembered that the metal uptake capacity of all isolates was approximately calculated. A box and reactor were designed to house these optimized microorganisms. Based on biochemical, morphological, and molecular results, the isolated strain was found to be closely related to the Bacillus genus. In the first five steps of testing, the ideal pH for removing lead alone, lead with cadmium, lead with nickel, and lead ternary (with cadmium and nickel) by Bacillus bacteria was found to be 7, 6, 5.5, and 6.5, respectively. The absorption efficiencies for single lead (unary), lead together with nickel, cadmium (binary), and ternary (lead with cadmium and nickel) were found to be 0.36, 0.25, 0.22, and 0.21 mmol/g, respectively. The ideal temperature for lead removal was around 30 °C. The adsorption isotherm for each lead metal in different states was found to be similar to the Langmuir isotherm, indicating that the surface absorption process is a single-layer process. The kinetics of the process follow the second-order kinetic model. The amount of Bacillus bacteria biomass obtained during this process was approximately 1.5 g per liter.}, }
@article {pmid39160204, year = {2024}, author = {Nahum, Y and Gross, N and Cerrone, A and Matouš, K and Nerenberg, R}, title = {Effect of biofilm physical characteristics on their susceptibility to antibiotics: impacts of low-frequency ultrasound.}, journal = {NPJ biofilms and microbiomes}, volume = {10}, number = {1}, pages = {70}, pmid = {39160204}, issn = {2055-5008}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Anti-Bacterial Agents/pharmacology ; *Tobramycin/pharmacology ; *Pseudomonas aeruginosa/drug effects/physiology ; Microbial Sensitivity Tests ; Microbial Viability/drug effects ; Ultrasonic Waves ; }, abstract = {Biofilms are highly resistant to antimicrobials, often causing chronic infections. Combining antimicrobials with low-frequency ultrasound (LFU) enhances antimicrobial efficiency, but little is known about the underlying mechanisms. Biofilm physical characteristics, which depend on factors such as growth conditions and age, can have significant effects on inactivation efficiency. In this study, we investigated the susceptibility of Pseudomonas aeruginosa biofilms to tobramycin, with and without LFU treatment. The biofilms were grown under low and high fluid shear to provide different characteristics. Low-shear biofilms exhibited greater thickness, roughness, and porosity and lower density, compared to high-shear biofilms. The biofilm matrix of the high-shear biofilms had a three times higher protein-to-polysaccharide ratio, suggesting greater biofilm stiffness. This was supported by microrheology measurements of biofilm creep compliance. For the low-shear biofilms without LFU, the viability of the biofilms in their inner regions was largely unaffected by the antibiotic after a 2-hour treatment. However, when tobramycin was combined with LFU, the inactivation for the entire biofilm increased to 80% after 2 h. For the high-shear biofilms without LFU, higher LFU intensities were needed to achieve similar inactivation results. Microrheology measurements revealed that changes in biofilm inactivation profiles were closely related to changes in biofilm mechanical properties. Modeling suggests that LFU changes antibiotic diffusivity within the biofilm, probably due to a "decohesion" effect. Overall, this research suggests that biofilm physical characteristics (e.g., compliance, morphology) are linked to antimicrobial efficiency. LFU weakens the biofilm while increasing its diffusivity for antibiotics.}, }
@article {pmid39159773, year = {2024}, author = {Biswas, T and Ahmed, M and Mondal, S}, title = {Mixed species biofilm: Structure, challenge and its intricate involvement in hospital associated infections.}, journal = {Microbial pathogenesis}, volume = {195}, number = {}, pages = {106866}, doi = {10.1016/j.micpath.2024.106866}, pmid = {39159773}, issn = {1096-1208}, mesh = {*Biofilms/growth &amp; development ; Humans ; *Cross Infection/microbiology ; Bacteria/classification ; Anti-Bacterial Agents/pharmacology/therapeutic use ; Microbial Interactions ; Extracellular Polymeric Substance Matrix/metabolism ; }, abstract = {Hospital associated infections or healthcare associated infections (HAIs) are a major threat to healthcare and medical management, mostly because of their recalcitrant nature. The primary cause of these HAIs is bacterial associations, especially the interspecies interactions. In interspecies interactions, more than one species co-exists in a common platform of extracellular polymeric substances (EPS), establishing a strong interspecies crosstalk and thereby lead to the formation of mixed species biofilms. In this process, the internal microenvironment and the surrounding EPS matrix of the biofilms ensure the protection of the microorganisms and allow them to survive under antagonistic conditions. The communications between the biofilm members as well as the interactions between the bacterial cells and the matrix polymers, also aid in the rigidity of the biofilm structure and allow the microorganisms to evade both the host immune response and a wide range of anti-microbials. Therefore, to design a treatment protocol for HAIs is difficult and it has become a growing point of concern. This review therefore first aims to discuss the role of microenvironment, molecular structure, cell-cell communication, and metabolism of mixed species biofilms in manifestation of HAIs. In addition, we discuss the electrochemical properties of mixed-species biofilms and their mechanism in developing drug resistance. Then we focus on the most dreaded bacterial HAI including oral and gut multi-species infections, catheter-associated urinary tract infections, surgical site infections, and ventilator-associated pneumonia. Further, we highlight the challenges to eradication of the mixed species biofilms and the current and prospective future strategies for the treatment of mixed species-associated HAI. Together, the review presents a comprehensive understanding of mixed species biofilm-mediated infections in clinical scenario, and summarizes the current challenge and prospect of therapeutic strategies against HAI.}, }
@article {pmid39159772, year = {2024}, author = {Carmona-Orozco, ML and Echeverri, F}, title = {Induction of biofilm in extended-spectrum beta-lactamase Staphylococcus aureus with drugs commonly used in pharmacotherapy.}, journal = {Microbial pathogenesis}, volume = {195}, number = {}, pages = {106863}, doi = {10.1016/j.micpath.2024.106863}, pmid = {39159772}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Anti-Bacterial Agents/pharmacology ; Humans ; *Staphylococcus aureus/drug effects ; *Microbial Sensitivity Tests ; *Staphylococcal Infections/microbiology/drug therapy ; *beta-Lactamases/metabolism ; Methicillin-Resistant Staphylococcus aureus/drug effects ; }, abstract = {Staphylococcus aureus is a bacterial pathogen that causes bloodstream infections, pneumonia, and skin abscesses and is the primary pathogen responsible for medical devices associated with biofilm infections, accounting for approximately 70 % of cases. Therefore, the World Health Organization (WHO) has designated this microorganism as a top priority due to its role in causing over 20,000 bacteremia-related deaths in the US each year. The issue of pathogen resistance to antibiotics, mainly by a biofilm, further complicates these infections since biofilms render the bacterial colony impervious to antibiotics. However, many natural and synthetic substances also induce bacterial biofilm formation. Therefore, we investigated whether the most common active pharmaceutical ingredients (APIs) could induce biofilm formation in two clinical isolates of extended-spectrum beta-lactamase Staphylococcus aureus, one of them also methicillin-resistant (A2M) and two medical devices. We detected biofilm inducers, inhibitors, and destabilizers. Microbial strain, medical devices, API structure, and concentration influenced the modulatory effects of biofilm. In all devices tested, including microplates, FR18 duodenal probe, and respiratory probe, the clinic isolate methicillin-resistant S. aureus A2M exhibited lower susceptibility to biofilm formation than S. aureus A1. The anti-inflammatory acetaminophen, the hypocholesterolemic lovastatin, and the diuretic hydrochlorothiazide all induced biofilm. However, verapamil, an antihypertensive, and cetirizine, an antihistamine, inhibited biofilm on S. aureus A2M, while propranolol, another antihypertensive, inhibited biofilm on S. aureus A1. Additionally, diclofenac, an analgesic, and cetirizine destabilized the biofilm, resulting in more free bacteria and possibly making them more susceptible to external agents such as antibiotics. Nonetheless, further epidemiologic analyses and in vivo assays are needed to confirm these findings and to establish a correlation between drug use, the onset of bacterial infections in patients, and the use of medical devices. This work provides information about the probable clinical implications of drugs in patients using medical devices or undergoing surgical procedures. Inhibitory APIs could also be used as drug repurposing or templates to design new, more potent biofilm inhibitors.}, }
@article {pmid39159744, year = {2024}, author = {Magalhães, TC and Lopes, AG and Ferreira, GF and Denadai, &#xc2;ML and da Silva, JG and Dos Santos, RL and Munchow, EA and de Carvalho, FG}, title = {In vitro assessment of NaF/Chit supramolecular complex: Colloidal stability, antibacterial activity and enamel protection against S. mutans biofilm.}, journal = {Journal of dentistry}, volume = {149}, number = {}, pages = {105316}, doi = {10.1016/j.jdent.2024.105316}, pmid = {39159744}, issn = {1879-176X}, mesh = {*Biofilms/drug effects ; *Streptococcus mutans/drug effects ; *Dental Enamel/drug effects/microbiology ; Humans ; *Anti-Bacterial Agents/pharmacology ; *Sodium Fluoride/pharmacology ; *Chitosan/pharmacology/chemistry ; *Microbial Sensitivity Tests ; Spectroscopy, Fourier Transform Infrared ; Mouthwashes/pharmacology/chemistry ; Colloids ; Cariostatic Agents/pharmacology/chemistry ; }, abstract = {OBJECTIVES: This study assessed the effect of NaF/Chit suspensions on enamel and on S. mutans biofilm, simulating application of a mouthrinse.<br><br>METHODS: The NaF/Chit particle suspensions were prepared at molar ratio [NaF]/Chitmon]&#x2248;0.68 at nominal concentrations of 0.2 % and 0.05 % NaF and characterized by Fourier transform infrared spectroscopy (FTIR), dynamic light scattering and zeta potential. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were measured. The S. mutans biofilm was formed for 7 days on eighty human enamel blocks that were divided into eight groups (n = 10/group): i) 0.05 % NaF solution; ii) 0.31 % Chit solution; iii) NaF/Chit(R=0.68) suspension at 0.05 % NaF; iv) 1.0 % HAc solution (Control); v) 0.2 % NaF solution; vi) 1.25 % Chit solution; vii) NaF/Chit(R=0.68) suspension at 0.2 % NaF; viii) 0.12 % chlorhexidine digluconate. The substances were applied daily for 90 s. S. mutans cell counts (CFU/mL) were performed, and the Knoop microhardness (KHN) of enamel samples were measured before and after biofilm formation. The KHN and CFU/mL data were analyzed by repeated measure ANOVA and Tukey's test (&#x3b1; = 0.05).<br><br>RESULTS: Interactions between NaF and Chit were evidenced in solid state by FTIR spectra. The NaF/Chit complexes showed spontaneous microparticle formation and colloidal stability. The MIC and MBC ranged from 0.65 to 1.31 mg/mL. The NaF/Chit(R=0.68) suspension at 0.2 %NaF Group showed lower CFU/mL values than other groups. The NaF/Chit(R=0.68) suspensions Groups had the highest KHN values after biofilm formation.<br><br>CONCLUSIONS: The NaF/Chit(R=0.68) complexes exhibited an antibacterial effect against S. mutans biofilm and reduced the enamel hardness loss.<br><br>CLINICAL SIGNIFICANCE: The NaF/Chit(R=0.68) suspensions showed potential to be used as a mouthrinse for caries prevention.}, }
@article {pmid39158270, year = {2024}, author = {Nairn, BL and Lima, BP and Chen, R and Yang, JQ and Wei, G and Chumber, AK and Herzberg, MC}, title = {Effects of fluid shear stress on oral biofilm formation and composition and the transcriptional response of Streptococcus gordonii.}, journal = {Molecular oral microbiology}, volume = {39}, number = {6}, pages = {477-490}, doi = {10.1111/omi.12481}, pmid = {39158270}, issn = {2041-1014}, support = {K08 DE027705/DE/NIDCR NIH HHS/United States ; R01 DE025618/DE/NIDCR NIH HHS/United States ; R03 DE031337/DE/NIDCR NIH HHS/United States ; 2236497//National Science Foundation/ ; }, mesh = {*Biofilms/growth &amp; development ; *Streptococcus gordonii/genetics/physiology ; *Dental Plaque/microbiology ; Humans ; *Stress, Mechanical ; Biomass ; Mouth/microbiology ; Gene Expression Profiling ; Gene Expression Regulation, Bacterial ; Shear Strength ; }, abstract = {Biofilms are subjected to many environmental pressures that can influence community structure and physiology. In the oral cavity, and many other environments, biofilms are exposed to forces generated by fluid flow; however, our understanding of how oral biofilms respond to these forces remains limited. In this study, we developed a linear rocker model of fluid flow to study the impact of shear forces on Streptococcus gordonii and dental plaque-derived multispecies biofilms. We observed that as shear forces increased, S. gordonii biofilm biomass decreased. Reduced biomass was largely independent of overall bacterial growth. Transcriptome analysis of S. gordonii biofilms exposed to moderate levels of shear stress uncovered numerous genes with differential expression under shear. We also evaluated an ex vivo plaque biofilm exposed to fluid shear forces. Like S. gordonii, the plaque biofilm displayed decreased biomass as shear forces increased. Examination of plaque community composition revealed decreased diversity and compositional changes in the plaque biofilm exposed to shear. These studies help to elucidate the impact of fluid shear on oral bacteria and may be extended to other bacterial biofilm systems.}, }
@article {pmid39156801, year = {2024}, author = {Naziri, Z and Hajihasani, A and Derakhshandeh, A}, title = {Investigation of antibiotic resistance, virulence genes, and biofilm formation of Escherichia coli isolated from sheep feces in Shiraz industrial slaughterhouse, South of Iran.}, journal = {Iranian journal of veterinary research}, volume = {25}, number = {1}, pages = {25-32}, pmid = {39156801}, issn = {1728-1997}, abstract = {BACKGROUND: With the increase in human population, the consumption of livestock products such as sheep meat has also increased. Sheep are the reservoir and shedder of Escherichia coli that can be transmitted to humans. Aims: Characterization of fecal E. coli isolated from sheep in slaughterhouse.<br><br>METHODS: Stool specimens were collected from 30 apparently healthy sheep from different flocks in Shiraz industrial slaughterhouse. The resistance of E. coli isolates against 10 antibiotics was determined by disk diffusion method. The presence of three major extended spectrum beta-lactamase (ESBL) genes and five tetracycline resistance genes as well as seven virulence genes were investigated by polymerase chain reaction (PCR) technique. Using the microtiter plate method, the biofilm formation ability of E. coli isolates was investigated.<br><br>RESULTS: The highest frequency of resistance was to amoxicillin (100%) followed by tetracycline (25%). All E. coli isolates were susceptible to gentamicin and nitrofurantoin, and only one isolate was resistant to the tested third-generation cephalosporins. Multidrug resistance phenotype was observed in 16.7% of the isolates. bla TEM (25%) was the most prevalent ESBL gene and tetA (62.5%) was the most prevalent tetracycline resistance gene in the isolates. crl, csgA, fimH, and bcsA genes were present in all isolates, and the prevalence of papC and afa genes was 95.8% and 83.3%, respectively. In total, 62.5% of the isolates were biofilm producers.<br><br>CONCLUSION: According to the concept of One Health, the presence of virulent antibiotic-resistant biofilm producing strains of E. coli in sheep is a risk to public health.}, }
@article {pmid39155946, year = {2024}, author = {Godart, GA and Elwasila, SM and Durvasula, RV}, title = {A rare case of candida osteomyelitis of the mandible associated with osteoradionecrosis and biofilm formation.}, journal = {IDCases}, volume = {37}, number = {}, pages = {e02029}, pmid = {39155946}, issn = {2214-2509}, abstract = {Candida osteomyelitis, in general, is a relatively rare manifestation compared to its bacterial counterparts. The mandible's involvement is rarer, lacking established management and fewer guidelines. Herein, we aim to illustrate the significant challenge in treatment, namely due to the persistent and resistant nature of Candida albicans-associated biofilm. A multidisciplinary approach involving adjunctive use of antifungals with surgical interventions is typically necessary and feasible in this case. However, surgical interventions may not always be possible in challenging instances in which the patient may be structurally (including osteoradionecrosis) and vascularly compromised, raising questions about the feasibility of standard-of-care as well as the success of alternative therapies aimed at disrupting biofilm formation. Clinicians should maintain a high index of suspicion for complicating, deep-seated Candidiasis in at-risk populations and endeavor to treat as aggressively as possible to limit recurrent disease owing to persistence.}, }
@article {pmid39155705, year = {2024}, author = {Tan, S and Huang, Y and Yang, H and Zhang, S and Tang, X}, title = {Microbial communities and denitrification mechanisms of pyrite autotrophic denitrification coupled with three-dimensional biofilm electrode reactor.}, journal = {Water environment research : a research publication of the Water Environment Federation}, volume = {96}, number = {8}, pages = {e11107}, doi = {10.1002/wer.11107}, pmid = {39155705}, issn = {1554-7531}, support = {21806126//National Natural Science Foundation of China/ ; WUT.2019IVB031//Fundamental Research Funds for the Central Universities/ ; }, mesh = {*Denitrification ; *Biofilms ; *Bioreactors ; *Electrodes ; *Sulfides/metabolism/chemistry ; Autotrophic Processes ; Iron/metabolism ; Bacteria/metabolism/classification/genetics ; Nitrates/metabolism ; Microbiota ; }, abstract = {Denitrification is of great significance for low C/N wastewater treatment. In this study, pyrite autotrophic denitrification (PAD) was coupled with a three-dimensional biofilm electrode reactor (BER) to enhance denitrification. The effect of current on denitrification was extensively studied. The nitrate removal of the PAD-BER increased by 14.90% and 74.64% compared to the BER and the PAD, respectively. In addition, the electron utilization, extracellular polymeric substances secretion, and denitrification enzyme activity (NaR and NiR) were enhanced in the PAD-BER. The microbial communities study displayed that Dokdonella, Hydrogenophaga, Nitrospira, and Terrimonas became the main genera for denitrification. Compared with the PAD and the BER, the abundance of the key denitrification genes narG, nirK, nirS, and nosZ were all boosted in the PAD-BER. This study indicated that the enhanced autotrophic denitrifiers and denitrification genes were responsible for the improved denitrification in the PAD-BER. PRACTITIONER POINTS: PAD-BER displayed higher nitrate removal, EPS, NAR, and NIR activity. The three types of denitrification (HD, HAD, and PAD) and their contribution percentage in the PAD-BER were analyzed. HAD was dominant among the three denitrification processes in PAD-BER. Microbial community composition and key denitrification genes were tested to reveal the denitrification mechanisms.}, }
@article {pmid39155413, year = {2024}, author = {Yang, K and Wang, L and Chen, J and Wang, Z and Li, J and Chen, X and Fu, S and Hai, L and Deng, L and He, D}, title = {H2O2-Activatable Liposomal Nanobomb Capable of Generating Hypoxia-Irrelevant Alkyl Radicals by Photo-Triggered Cascade Reaction for High-Performance Elimination of Biofilm Bacteria.}, journal = {Advanced healthcare materials}, volume = {13}, number = {31}, pages = {e2402136}, doi = {10.1002/adhm.202402136}, pmid = {39155413}, issn = {2192-2659}, support = {22375061//National Natural Science Foundation of China/ ; 21775036//National Natural Science Foundation of China/ ; 22005343//National Natural Science Foundation of China/ ; 2021SK2053//Key Research and Development Program of Hunan Province/ ; 2022RC1164//Science and Technology Innovation Program of Hunan Province/ ; 22A0031//Research Foundation of Education Department of Hunan Province/ ; 2022JJ30379//Natural Science Foundation of Hunan Province/ ; ZDSYS20220606101604009//Shenzhen Science and Technology Program/ ; }, mesh = {*Hydrogen Peroxide/chemistry ; *Nanocomposites/chemistry ; *Liposomes/chemistry/pharmacology ; Benzothiazoles/chemistry ; Sulfonic Acids/chemistry ; Azo Compounds/chemistry ; Imidazoles/chemistry ; Free Radicals/chemistry ; *Biofilms/drug effects ; Animals ; Mice ; Mice, Inbred BALB C ; Random Allocation ; *Staphylococcus aureus/drug effects/physiology ; *Staphylococcal Infections/drug therapy ; *Anti-Bacterial Agents/chemistry/pharmacology ; }, abstract = {High H2O2 levels are widely present at the infection sites or in the biofilm microenvironment. Herein, hemin with peroxidase-like catalytic activity and its substrate, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), are simultaneously introduced into a liposomal nanoparticle containing thermosensitive 2,2'-azobis[2-(2-imidazolin-2-yl) propane] dihydrochloride (AIBI)-loaded bovine serum albumin (BAG), rationally constructing an H2O2-activatable liposomal nanobomb (Lipo@BHA) for combating biofilm-associated bacterial infections with high performance. In the presence of H2O2, hemin can catalyze the conversion of ABTS into its oxidized form (ABTS·[+]) with strong near-infrared (NIR) absorption, which produces photonic hyperpyrexia to cause the decomposition of AIBI into oxygen-independent alkyl radicals (·R) and nitrogen (N2) microbubbles. The former not only directly damage bacterial cells but also significantly accelerates the oxidization of ABTS to ABTS·[+] for augmenting photothermal-triggered generation of ·R. Interestingly, the released N2 can induce transient cavitation to rupture lysosomal nanoparticle and improve the biofilm permeability, thereby enhancing the antibiofilm effect of Lipo@BHA. The proposed Lipo@BHA exhibits satisfactory multi-mode combination antibacterial properties. Through endogenous H2O2-activated cascade reaction, Lipo@BHA achieves remarkable hypoxia-irrelevant ·R therapy of biofilm-associated wound infections with low cytotoxicity and good in vivo biosafety. Therefore, this work presents a versatile H2O2-activatable cascade ·R generation strategy for biofilm-specific therapeutic applications.}, }
@article {pmid39154385, year = {2024}, author = {Li, Z and Wang, Q and Lei, Z and Zheng, H and Zhang, H and Huang, J and Ma, Q and Li, F}, title = {Biofilm formation and microbial interactions in moving bed-biofilm reactors treating wastewater containing pharmaceuticals and personal care products: A review.}, journal = {Journal of environmental management}, volume = {368}, number = {}, pages = {122166}, doi = {10.1016/j.jenvman.2024.122166}, pmid = {39154385}, issn = {1095-8630}, mesh = {*Biofilms ; *Wastewater/chemistry ; *Bioreactors ; Microbial Interactions ; Pharmaceutical Preparations ; Waste Disposal, Fluid/methods ; Cosmetics ; Water Pollutants, Chemical ; Water Purification/methods ; Humans ; }, abstract = {The risk of pharmaceuticals and personal care products (PPCPs) has been paid more attention after the outbreak of COVID-19, threatening the ecology and human health resulted from the massive use of drugs and disinfectants. Wastewater treatment plants are considered the final stop to restrict PPCPs from wide spreading into the environment, but the performance of conventional treatment is limited due to their concentrations and characteristics. Previous studies have shown the unreplaceable capability of moving bed-biofilm reactor (MBBR) as a cost-effective method with layered microbial structure for treating wastewater even with toxic compounds. The biofilm community and microbial interactions are essential for the MBBR process in completely degrading or converting types of PPCPs to secondary metabolites, which still need further investigation. This review starts with discussing the initiation of MBBR formation and its influencing parameters according to the research on MBBRs in the recent years. Then the efficiency of MBBRs and the response of biofilm after exposure to PPCPs are further addressed, followed by the bottlenecks proposed in this field. Some critical approaches are also recommended for mitigating the deficiencies of MBBRs based on the recently published publications to reduce the environmental risk of PPCPs. Finally, this review provides fundamental information on PPCPs removal by MBBRs with the main focus on microbial interactions, promoting the MBBRs to practical application in the real world of wastewater treatment.}, }
@article {pmid39153696, year = {2024}, author = {Xu, H and Yang, XL and Zhang, ZH and Xia, YG and Song, HL}, title = {External circuit loading mode regulates anode biofilm electrochemistry and pollutants removal in microbial fuel cells.}, journal = {Bioresource technology}, volume = {410}, number = {}, pages = {131300}, doi = {10.1016/j.biortech.2024.131300}, pmid = {39153696}, issn = {1873-2976}, mesh = {*Bioelectric Energy Sources ; *Electrodes ; *Biofilms/drug effects ; Biological Oxygen Demand Analysis ; Water Pollutants, Chemical ; Sulfamethoxazole ; Electrochemistry/methods ; Bacteria/metabolism/drug effects ; Electricity ; }, abstract = {This study investigated the effects of different external circuit loading mode on pollutants removal and power generation in microbial fuel cells (MFC). The results indicated that MFC exhibited distinct characteristics of higher maximum power density (Pmax) (named MFC-HP) and lower Pmax (named MFC-LP). And the capacitive properties of bioanodes may affect anodic electrochemistry. Reducing external load to align with the internal resistance increased Pmax of MFC-LP by 54.47 %, without no obvious effect on MFC-HP. However, intermittent external resistance loading (IER) mitigated the biotoxic effects of sulfamethoxazole (SMX) (a persistent organic pollutant) on chemical oxygen demand (COD) and NH4[+]-N removal and maintained high Pmax (424.33 mW/m[2]) in MFC-HP. Meanwhile, IER mode enriched electrochemically active bacteria (EAB) and environmental adaptive bacteria Advenella, which may reduce antibiotic resistance genes (ARGs) accumulation. This study suggested that the external circuit control can be effective means to regulate electrochemical characteristics and pollutants removal performance of MFC.}, }
@article {pmid39153576, year = {2024}, author = {Dias, GR and Freitas-Silva, J and de Carvalho, MM and Ramos, VFDS and Muricy, G and Rodrigues, JCF and Costa, BRFV and de Oliveira, BFR and Laport, MS}, title = {Bioemulsifier from sponge-associated bacteria reduces staphylococcal biofilm.}, journal = {Microbial pathogenesis}, volume = {195}, number = {}, pages = {106856}, doi = {10.1016/j.micpath.2024.106856}, pmid = {39153576}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Porifera/microbiology ; Animals ; *Bacterial Adhesion/drug effects ; *Staphylococcus aureus/drug effects/physiology ; *Emulsifying Agents/pharmacology/chemistry ; Staphylococcus epidermidis/drug effects/physiology ; Escherichia coli/drug effects/physiology ; Hydrophobic and Hydrophilic Interactions ; Anti-Bacterial Agents/pharmacology ; Bacillus cereus/drug effects/physiology ; Hemolysis ; Surface-Active Agents/pharmacology/metabolism ; Vibrio/drug effects/physiology/metabolism ; Microbial Sensitivity Tests ; Gram-Negative Bacteria/drug effects/physiology ; }, abstract = {Biofilm formation is a major health concern and studies have been pursued to find compounds able to prevent biofilm establishment and remove pre-existing biofilms. While biosurfactants (BS) have been well-known for possessing antibiofilm activities, bioemulsifiers (BE) are still scarcely explored for this purpose. The present study aimed to evaluate the bioemulsifying properties of cell-free supernatants produced by Bacillaceae and Vibrio strains isolated from marine sponges and investigate their antiadhesive and antibiofilm activities against different pathogenic Gram-positive and Gram-negative bacteria. The BE production by the marine strains was confirmed by the emulsion test, drop-collapsing, oil-displacement, cell hydrophobicity and hemolysis assays. Notably, Bacillus cereus 64BHI1101 displayed remarkable emulsifying activity and the ultrastructure analysis of its BE extract (BE64-1) revealed the presence of structures typically observed in macromolecules composed of polysaccharides and proteins. BE64-1 showed notable antiadhesive and antibiofilm activities against Staphylococcus aureus, with a reduction of adherence of up to 100 % and a dispersion of biofilm of 80 %, without affecting its growth. BE64-1 also showed inhibition of Staphylococcus epidermidis and Escherichia coli biofilm formation and adhesion. Thus, this study provides a starting point for exploring the antiadhesive and antibiofilm activities of BE from sponge-associated bacteria, which could serve as a valuable tool for future research to combat S. aureus biofilms.}, }
@article {pmid39153575, year = {2024}, author = {Sikdar, B and Mukherjee, S and Bhattacharya, R and Raj, A and Roy, A and Banerjee, D and Gangopadhyay, G and Roy, S}, title = {The anti-quorum sensing and biofilm inhibitory potential of Piper betle L. leaf extract and prediction of the roles of the potent phytocompounds.}, journal = {Microbial pathogenesis}, volume = {195}, number = {}, pages = {106864}, doi = {10.1016/j.micpath.2024.106864}, pmid = {39153575}, issn = {1096-1208}, mesh = {*Quorum Sensing/drug effects ; *Biofilms/drug effects ; *Plant Extracts/pharmacology/chemistry ; *Pseudomonas aeruginosa/drug effects ; *Piper betle/chemistry ; *Plant Leaves/chemistry ; *Chromobacterium/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Microbial Sensitivity Tests ; *Virulence Factors ; *Molecular Docking Simulation ; Phytochemicals/pharmacology/chemistry ; Gene Expression Regulation, Bacterial/drug effects ; Bacterial Proteins/metabolism/genetics ; }, abstract = {The leaves of Piper betle L., known as betel leaf, have immense medicinal properties. It possesses potent antimicrobial efficacies and can be a valuable tool to combat drug-resistant microorganisms. Quorum sensing (QS) inhibition is one of the best strategies to combat drug resistance. The present study investigates the anti-quorum sensing and biofilm inhibitory potential of Piper betle L. leaf extract against two bacterial strains, Chromobacterium violaceum and Pseudomonas aeruginosa. The extract produced substantial QS-inhibition zones in a biosensor strain of C. violaceum (CV026), indicating interference with quorum-sensing signals. The Results demonstrated significant inhibition in biofilm formation and different QS-regulated virulence factors (violacein, exopolysaccharides, pyocyanin, pyoverdine, elastase) in both C. violaceum and P. aeruginosa at sub-MIC concentrations of the extract and tetracycline, an antibiotic with known anti-QS activity. The quantitative real-time PCR (qRT-PCR) revealed decreased gene expression in different QS-related genes in C. violaceum (cviI, cviR, and vioA) and P. aeruginosa (lasI, lasR, lasB, rhlI, rhlR, and rhlA) strains after treatment. Gas Chromatography-Mass Spectrometry (GC-MS) analysis identified the significant phytocompounds, mainly derivatives of chavicol and eugenol, in the extract. Of these compounds, chavicol acetate (affinity: -7.00 kcal/mol) and acetoxy chavicol acetate (affinity: -7.87 kcal/mol) showed the highest potential to bind with the CviR and LasR protein, respectively, as evident from the in-silico molecular docking experiment. The findings of this endeavour highlight the promising role of Piper betle L. as a source of natural compounds with anti-quorum sensing properties against pathogenic bacteria, opening avenues for developing novel therapeutic agents to combat bacterial infections.}, }
@article {pmid39153098, year = {2024}, author = {Estrada-Arriaga, EB and Montero-Farías, R and Morales-Morales, C and García-Sánchez, L and Falcón-Rojas, A and Garzón-Zúñiga, MA and Gutierrez-Macias, T}, title = {Performance of a pilot-scale microbial electrolysis cell coupled with biofilm-based reactor for household wastewater treatment: simultaneous pollutant removal and hydrogen production.}, journal = {Bioprocess and biosystems engineering}, volume = {47}, number = {11}, pages = {1929-1950}, pmid = {39153098}, issn = {1615-7605}, mesh = {*Biofilms/growth &amp; development ; *Hydrogen/metabolism ; *Bioreactors ; *Electrolysis ; *Wastewater/microbiology ; Water Purification/methods ; Waste Disposal, Fluid/methods ; Biological Oxygen Demand Analysis ; Bioelectric Energy Sources/microbiology ; Water Pollutants, Chemical/metabolism/isolation &amp; purification ; Pilot Projects ; Nitrogen/metabolism ; }, abstract = {The septic tank is the most commonly used decentralized wastewater treatment systems for household wastewater treatment in on-site applications. The removal rate of various pollutants is lower in different septic tank configurations. The integration of a microbial electrolysis cells (MEC) into septic tank or biofilm-based reactors can be a green and sustainable technology for household wastewater treatment and energy production. In this study, a 50-L septic tank was converted into a 50-L MEC coupled with biofilm-based reactor for simultaneous household wastewater treatment and hydrogen production. The biofilm-based reactor was integrated by an anaerobic packed-bed biofilm reactor (APBBR) and an aerobic moving bed biofilm reactor (aeMBBR). The MEC/APBBR/aeMBBR was evaluated at different organic loading rates (OLRs) by applying voltage of 0.7 and 1.0 V. Result showed that the increase of OLRs from 0.2 to 0.44 kg COD/m[3] d did not affect organic matter removals. Nutrient and solids removal decreased with increasing OLR up to 0.44 kg COD/m[3] d. Global removal of chemical oxygen demand (COD), biochemical oxygen demand (BOD), total nitrogen (TN), ammoniacal nitrogen (NH4[+]), total phosphorus (TP) and total suspended solids (TSS) removal ranged from 81 to 84%, 84 to 85%, 53 to 68%, 88 to 98%, 11 to 30% and 76 to 88% respectively, was obtained in this study. The current density generated in the MEC from 0 to 0.41 A/m[2] contributed to an increase in hydrogen production and pollutants removal. The maximum volumetric hydrogen production rate obtained in the MEC was 0.007 L/L[.]d (0.072 L/d). The integration of the MEC into biofilm-based reactors applying a voltage of 1.0 V generated different bioelectrochemical nitrogen and phosphorus transformations within the MEC, allowing a simultaneous denitrification-nitrification process with phosphorus removal.}, }
@article {pmid39150420, year = {2024}, author = {Xue, Y and Zhang, C and Li, S and Zhou, Q and Zhou, X and Zhang, Y}, title = {Enhanced denitrification by graphene oxide-modified cathode for the secondary effluent of wastewater treatment plants in three-dimensional biofilm electrode reactors.}, journal = {Water science and technology : a journal of the International Association on Water Pollution Research}, volume = {89}, number = {12}, pages = {3192-3207}, pmid = {39150420}, issn = {0273-1223}, support = {No. 2020YFD1100102//Key Technologies Research and Development Program/ ; }, mesh = {*Graphite/chemistry ; *Denitrification ; *Biofilms ; *Electrodes ; *Bioreactors ; *Waste Disposal, Fluid/methods ; *Wastewater/chemistry ; Nitrogen/chemistry ; Water Purification/methods ; }, abstract = {In this study, a novel three-dimensional biofilm electrode reactor (3D-BER) with a graphene oxide (GO)-modified cathode was developed to enhance the denitrification performance of secondary effluent from wastewater treatment plants (SEWTPs). The effects of different hydraulic retention times (HRTs) and currents on the 3D-BER were explored. The results indicated that at the optimal HRT of 4 h and current of 350 mA/m[2], the 3D-BER with GO-modified cathode had a higher denitrification rate (2.40 ± 0.1 mg TN/L/h) and less accumulation of intermediate products, especially with 3.34% total nitrogen (TN) molar conversion to N2O. The GO-modified cathode offered a large biocompatible specific surface area and enhanced the conductivity, which favored microbial growth and increased electron transfer efficiency and extracellular enzyme activities. Moreover, the activity of nitrite reductase increased more than that of nitrate reductase to accelerate nitrite reduction, thus facilitating the denitrification process. The proposed 3D-BER provided an effective solution to elevate tertiary denitrification in the SEWTP.}, }
@article {pmid39149593, year = {2024}, author = {Bai, X and Peng, W and Tang, Y and Wang, Z and Guo, J and Song, F and Yang, H and Huang, C}, title = {An NIR-propelled janus nanomotor with enhanced ROS-scavenging, immunomodulating and biofilm-eradicating capacity for periodontitis treatment.}, journal = {Bioactive materials}, volume = {41}, number = {}, pages = {271-292}, pmid = {39149593}, issn = {2452-199X}, abstract = {Periodontitis is an inflammatory disease caused by bacterial biofilms, which leads to the destruction of periodontal tissue. Current treatments, such as mechanical cleaning and antibiotics, struggle to effectively address the persistent biofilms, inflammation, and tissue damage. A new approach involves developing a Janus nanomotor (J-CeM@Au) by coating cerium dioxide-doped mesoporous silica (CeM) with gold nanoparticles (AuNPs). This nanomotor exhibits thermophoretic motion when exposed to near-infrared (NIR) laser light due to the temperature gradient produced by the photothermal effects of asymmetrically distributed AuNPs. The NIR laser provides the energy for propulsion and activates the nanomotor's antibacterial properties, allowing it to penetrate biofilms and kill bacteria. Additionally, the nanomotor's ability to scavenge reactive oxygen species (ROS) can modulate the immune response and create a regenerative environment, promoting the healing of periodontal tissue. Overall, this multifunctional nanomotor offers a promising new approach for treating periodontitis by simultaneously addressing biofilm management and immune modulation with autonomous movement.}, }
@article {pmid39149462, year = {2024}, author = {Fleeman, R and Beckman, R and Cella, E and Azarian, T and Rendueles, O}, title = {Diverse polysaccharide production and biofilm formation abilities of clinical Klebsiella pneumoniae.}, journal = {Research square}, volume = {}, number = {}, pages = {}, pmid = {39149462}, issn = {2693-5015}, support = {R00 AI163295/AI/NIAID NIH HHS/United States ; }, abstract = {Klebsiella pneumoniae infections have become a growing threat for human health. The lack of understanding of the relationship between antibiotic resistance, mucoviscosity, and biofilm formation in clinical isolates impedes our abilities to effectively predict K. pneumoniae infection outcomes. These traits are also associated with fitness in natural populations and more specifically within a host. The Multidrug-Resistant Organism Repository and Surveillance Network offers a unique opportunity into the genetic and phenotypic variabilities in the K. pneumoniae isolates encountered in the clinics today. To this end, we compared the genetic profiles of these isolates with the phenotypic biofilm formation abilities, percent mucoviscosity, and growth rates. We found most isolates formed limited biofilm, although a select group of isolates could form extremely robust biofilms. Variation in biofilm formation could not be explained by difference in growth rate, suggesting specific genetic and physical determinants. Interestingly, the most mucoid strains in the populations were lacking the genetic element regulating the mucoid phenotype and three of these isolates were able to form robust biofilms. There was a significant phenotype-genotype correlation with decreased biofilm formation and an insertion sequence in the transcriptional activator of the type III fimbrial system. Finally, confocal microscopy highlighted the structural and spatial heterogeneity of biofilm among the most robust biofilm formers not detected by traditional methods. The combination of phenotypic, genomic and image analyses allowed us to reveal an unexpected phenotypic diversity and an intricate relation between growth, mucoviscosity and specific virulence-associated genetic determinants.}, }
@article {pmid39149421, year = {2024}, author = {Chao, Y and Mørch, M and Håkansson, AP and Shannon, O}, title = {Biofilm-dispersed pneumococci induce elevated leukocyte and platelet activation.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1405333}, pmid = {39149421}, issn = {2235-2988}, mesh = {*Biofilms/growth &amp; development ; Humans ; *Streptococcus pneumoniae/immunology ; *Platelet Activation ; *Neutrophils/immunology ; Monocytes/immunology/microbiology ; Pneumococcal Infections/microbiology/immunology ; Blood Platelets/microbiology ; Leukocytes/immunology ; Flow Cytometry ; Adult ; Female ; Male ; }, abstract = {INTRODUCTION: Streptococcus pneumoniae (the pneumococcus) effectively colonizes the human nasopharynx, but can migrate to other host sites, causing infections such as pneumonia and sepsis. Previous studies indicate that pneumococci grown as biofilms have phenotypes of bacteria associated with colonization whereas bacteria released from biofilms in response to changes in the local environment (i.e., dispersed bacteria) represent populations with phenotypes associated with disease. How these niche-adapted populations interact with immune cells upon reaching the vascular compartment has not previously been studied. Here, we investigated neutrophil, monocyte, and platelet activation using ex vivo stimulation of whole blood and platelet-rich plasma with pneumococcal populations representing distinct stages of the infectious process (biofilm bacteria and dispersed bacteria) as well as conventional broth-grown culture (planktonic bacteria).<br><br>METHODS: Flow cytometry and ELISA were used to assess surface and soluble activation markers for neutrophil and monocyte activation, platelet-neutrophil complex and platelet-monocyte complex formation, and platelet activation and responsiveness.<br><br>RESULTS: Overall, we found that biofilm-derived bacteria (biofilm bacteria and dispersed bacteria) induced significant activation of neutrophils, monocytes, and platelets. In contrast, little to no activation was induced by planktonic bacteria. Platelets remained functional after stimulation with bacterial populations and the degree of responsiveness was inversely related to initial activation. Bacterial association with immune cells followed a similar pattern as activation.<br><br>DISCUSSION: Differences in activation of and association with immune cells by biofilm-derived populations could be an important consideration for other pathogens that have a biofilm state. Gaining insight into how these bacterial populations interact with the host immune response may reveal immunomodulatory targets to interfere with disease development.}, }
@article {pmid39149420, year = {2024}, author = {Zhang, Z and Pan, Y and Hussain, W and Chen, G and Li, E}, title = {BBSdb, an open resource for bacterial biofilm-associated proteins.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1428784}, pmid = {39149420}, issn = {2235-2988}, mesh = {*Biofilms/growth &amp; development ; *Bacterial Proteins/genetics/metabolism ; Bacteria/genetics/metabolism/classification ; Transcriptome ; Proteome ; Escherichia coli/genetics/metabolism ; Computational Biology/methods ; }, abstract = {Bacterial biofilms are organized heterogeneous assemblages of microbial cells encased within a self-produced matrix of exopolysaccharides, extracellular DNA and proteins. Over the last decade, more and more biofilm-associated proteins have been discovered and investigated. Furthermore, omics techniques such as transcriptomes, proteomes also play important roles in identifying new biofilm-associated genes or proteins. However, those important data have been uploaded separately to various databases, which creates obstacles for biofilm researchers to have a comprehensive access to these data. In this work, we constructed BBSdb, a state-of-the-art open resource of bacterial biofilm-associated protein. It includes 48 different bacteria species, 105 transcriptome datasets, 21 proteome datasets, 1205 experimental samples, 57,823 differentially expressed genes (DEGs), 13,605 differentially expressed proteins (DEPs), 1,930 'Top 5% differentially expressed genes', 444 'Threshold-based DEGs' and a predictor for prediction of biofilm-associated protein. In addition, 1,781 biofilm-associated proteins, including annotation and sequences, were extracted from 942 articles and public databases via text-mining analysis. We used E. coli as an example to represent how to explore potential biofilm-associated proteins in bacteria. We believe that this study will be of broad interest to researchers in field of bacteria, especially biofilms, which are involved in bacterial growth, pathogenicity, and drug resistance. Availability and implementation: The BBSdb is freely available at http://124.222.145.44/#!/.}, }
@article {pmid39149263, year = {2024}, author = {Williams, I and Tuckerman, JS and Peters, DI and Bangs, M and Williams, E and Shin, IJ and Kaspar, JR}, title = {A Strain of Streptococcus mitis Inhibits Biofilm Formation of Caries Pathogens via Abundant Hydrogen Peroxide Production.}, journal = {bioRxiv : the preprint server for biology}, volume = {}, number = {}, pages = {}, pmid = {39149263}, issn = {2692-8205}, support = {R03 DE031766/DE/NIDCR NIH HHS/United States ; }, abstract = {Commensal oral streptococci that colonize supragingival biofilms deploy mechanisms to combat competitors within their niche. Here, we determined that Streptococcus mitis more effectively inhibited biofilm formation of Streptococcus mutans within a seven species panel. This phenotype was common amongst all assayed isolates of S. mutans, but was specific to a single strain of S. mitis, ATCC 49456. The growth inhibitory factor was not effectively carried in spent supernatants of S. mitis. However, we documented ATCC 49456 to accumulate 4-5 times more hydrogen peroxide (H2O2) than other species tested, and 5-18 times more than other S. mitis strains assayed. The S. mutans biofilm formation inhibitory phenotype was reduced when grown in media containing catalase or with a S. mitis mutant of pyruvate oxidase (spxB; pox), confirming that SpxB-dependent H2O2 production was the main antagonistic factor. Addition of S. mitis within hours after S. mutans inoculation was effective at reducing biofilm biomass, but not for 24 h pre-formed biofilms. Transcriptome analysis revealed responses for both S. mitis and S. mutans, with several S. mutans differentially expressed genes following a gene expression pattern previously described, while others being unique to the interaction with S. mitis. Finally, we show that S. mitis also affected coculture biofilm formation of several other commensal streptococci. Our study shows that strains with abundant H2O2 production are effective at inhibiting initial growth of caries pathogens like S. mutans, but are less effective at disrupting pre-formed biofilms and have the potential to influence the stability of other oral commensal strains.}, }
@article {pmid39148892, year = {2024}, author = {Schlichter Kadosh, Y and Muthuraman, S and Nisaa, K and Ben-Zvi, A and Karsagi Byron, DL and Shagan, M and Brandis, A and Mehlman, T and Gopas, J and Saravana Kumar, R and Kushmaro, A}, title = {Pseudomonas aeruginosa quorum sensing and biofilm attenuation by a di-hydroxy derivative of piperlongumine (PL-18).}, journal = {Biofilm}, volume = {8}, number = {}, pages = {100215}, pmid = {39148892}, issn = {2590-2075}, abstract = {Bacterial communication, Quorum Sensing (QS), is a target against virulence and prevention of antibiotic-resistant infections. 16 derivatives of Piperlongumine (PL), an amide alkaloid from Piper longum L., were screened for QS inhibition. PL-18 had the best QSI activity. PL-18 inhibited the lasR-lasI, rhlR-rhlI, and pqs QS systems of Pseudomonas aeruginosa. PL-18 inhibited pyocyanin and rhamnolipids that are QS-controlled virulence elements. Iron is an essential element for pathogenicity, biofilm formation and resilience in harsh environments, its uptake was inhibited by PL-18. Pl-18 significantly reduced the biofilm biovolume including in established biofilms. PL-18-coated silicon tubes significantly inhibited biofilm formation. The transcriptome study of treated P. aeruginosa showed that PL-18 indeed reduced the expression of QS and iron homeostasis related genes, and up regulated sulfur metabolism related genes. Altogether, PL-18 inhibits QS, virulence, iron uptake, and biofilm formation. Thus, PL-18 should be further developed against bacterial infection, antibiotic resistance, and biofilm formation.}, }
@article {pmid39147521, year = {2024}, author = {Ren, F and Chen, Y and Yang, S and Zhang, Y and Liu, Y and Ma, Y and Wang, Y and Liu, Y and Dong, Q and Lu, D}, title = {Characterization of emetic Bacillus cereus biofilm formation and cereulide production in biofilm.}, journal = {Food research international (Ottawa, Ont.)}, volume = {192}, number = {}, pages = {114834}, doi = {10.1016/j.foodres.2024.114834}, pmid = {39147521}, issn = {1873-7145}, mesh = {*Bacillus cereus/metabolism/physiology ; *Biofilms/growth &amp; development ; *Depsipeptides/metabolism ; *Food Microbiology ; Microscopy, Confocal ; Animals ; Milk/microbiology ; Hot Temperature ; Extracellular Polymeric Substance Matrix/metabolism ; Foodborne Diseases/microbiology ; Food Handling/methods ; }, abstract = {Bacillus cereus is a well-known foodborne pathogen that can cause human diseases, including vomiting caused by emetic toxin, cereulide, requiring 10[5]-10[8] cells per gram to cause the disease. The bacterial cells may be eliminated during processing, but cereulide can survive in most processing techniques due to its resistance to high temperatures, extreme pH and proteolytic enzymes. Herein, we reported dynamic processes of biofilm formation of four different types and cereulide production within the biofilm. Confocal laser scanning microscopy (CLSM) images revealed that biofilms of the four different types reach each stage at different time points. Among the extracellular polymeric substances (EPS) components of the four biofilms formed by the emetic B. cereus F4810/72 strain, proteins account for the majority. In addition, there are significant differences (p < 0.05) in the EPS components at the same stage among biofilms of different types. The time point at which cereulide was first detected in the four types of biofilms was 24 h. In the biofilm of B. cereus formed in ultra-high-temperature (UHT) milk, the first peak of cereulide appeared at 72 h. The cereulide content of the biofilms formed in BHI was mostly higher than that of the biofilms formed in UHT milk. This study contributes to a better understanding of food safety issues in the industry caused by biofilm and cereulide toxin produced by B. cereus.}, }
@article {pmid39146677, year = {2024}, author = {Khalaf, MM and Gouda, M and Abou Taleb, MF and Heakal, FE and Abd El-Lateef, HM}, title = {Fabrication of smart nanogel based on carrageenan and green coffee extract as a long-term antifouling agent to improve biofilm prevention in food production.}, journal = {Food chemistry}, volume = {461}, number = {}, pages = {140719}, doi = {10.1016/j.foodchem.2024.140719}, pmid = {39146677}, issn = {1873-7072}, mesh = {*Carrageenan/pharmacology/chemistry ; *Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Plant Extracts/pharmacology/chemistry ; *Nanogels/chemistry ; *Microbial Sensitivity Tests ; *Staphylococcus aureus/drug effects ; Listeria monocytogenes/drug effects/growth &amp; development ; Coffee/chemistry ; Coffea/chemistry ; Bacteria/drug effects ; Salmonella enterica/drug effects ; }, abstract = {This study investigates the extract of the bioactive compounds from green coffee extract (GCE) and the loading of two different concentrations of GCE (1% and 2%) onto carrageenan nanogels (CAR NGs) to compare their antibacterial and antibiofilm effects with unloaded nanogels (NGs). The bioactive compounds of GCE were characterized using GC-MS analysis. The GCE1 and GCE2 were successfully deposited onto the surface of CAR NGs. The antibacterial and antibiofilm potential of prepared NGs were conducted against some foodborne pathogens (E. coli O157, Salmonella enterica, Staphylococcus aureus, and Listeria monocytogenes). The results of GC-MS analysis indicated that there were identified 16 bioactive compounds in GCE, including caffeine (36.27%), Dodemorph (9.04%), and D-Glycero-d-ido-heptose (2.44%), contributing to its antimicrobial properties. The antibacterial coatings demonstrated a notable antimicrobial effect, showing zone of inhibition (ZOI) diameters of up to 37 mm for GCE2 loaded CAR NGs. The minimum inhibitory concentration (MIC) values for GCE2 loaded CAR NGs were 80 ppm for E. coli O157, and 120 ppm for S. enterica, S. aureus, and L. monocytogenes, achieving complete bacterial inactivation within 10-15 min of exposure. Both GCE1 and GCE2 loaded CAR NGs significantly reduced biofilm cell densities on stainless steel (SS) materials for E. coli O157, S. enterica, S. aureus, and L. monocytogenes, with reductions ranging from 60% to 95%. Specifically, biofilm densities were reduced by up to 95% for E. coli O157, 89% for S. enterica, 85% for S. aureus, and 80% for L. monocytogenes. Results of the toxicity evaluation indicated that the NGs were non-toxic and biocompatible, with predicted EC50 values proved their biocompatibility and safety. These results recommended that GCE loaded CAR NGs are promising as natural antimicrobial agents for enhancing food safety and extending shelf life. Further, the study concluded that incorporating GCE into CAR NGs is an effective strategy for developing sustainable antimicrobial coatings for the food industry and manufacturing.}, }
@article {pmid39146626, year = {2024}, author = {Pramana, A and Firmanda, A and Arnata, IW and Sartika, D and Sari, EO}, title = {Reduction of biofilm and pathogenic microorganisms using curcumin-mediated photodynamic inactivation to prolong food shelf-life.}, journal = {International journal of food microbiology}, volume = {425}, number = {}, pages = {110866}, doi = {10.1016/j.ijfoodmicro.2024.110866}, pmid = {39146626}, issn = {1879-3460}, mesh = {*Curcumin/pharmacology ; *Biofilms/drug effects ; *Photosensitizing Agents/pharmacology ; *Food Microbiology ; *Bacteria/drug effects/growth &amp; development/radiation effects/metabolism ; *Food Preservation/methods ; *Fungi/drug effects ; Food Storage ; Reactive Oxygen Species/metabolism ; Food Contamination/prevention &amp; control ; }, abstract = {Pathogenic microbial contamination (bacteria and fungi) in food products during production poses a significant global health risk, leading to food waste, greenhouse gas emissions, and aesthetic and financial losses. Bacteria and fungi, by forming solid biofilms, enhance their resistance to antimicrobial agents, thereby increasing the potential for cross-contamination of food products. Curcumin molecule-mediated photodynamic inactivation (Cur-m-PDI) technology has shown promising results in sterilizing microbial contaminants and their biofilms, significantly contributing to food preservation without compromising quality. Photosensitizers (curcumin) absorb light, leading to a chemical reaction with oxygen and producing reactive oxygen species (ROS) that effectively reduce bacteria, fungi, and biofilms. The mechanism of microorganism inhibition is caused by exposure to ROS generated via the type 1 pathway involving electron transfer (such as O2•[-], H2O2, -OH•, and other radicals), the type 2 pathway involving energy transfer (such as [1]O2), secondary ROS, and weakening of antioxidant enzymes. The effectiveness of the inactivation of microorganisms is influenced by the concentration of curcumin, light (source type and energy density), oxygen availability, and duration of exposure. This article reviews the mechanism of reducing microbial food contamination and inhibiting their biofilms through Cur-m-PDI. It also highlights future directions, challenges, and considerations related to the effects of ROS in oxidizing food, the toxicity of PDI to living cells and tissues, conditions/types of food products, and the stability and degradation of curcumin.}, }
@article {pmid39145307, year = {2024}, author = {Tekedar, HC and Patel, F and Blom, J and Griffin, MJ and Waldbieser, GC and Kumru, S and Abdelhamed, H and Dharan, V and Hanson, LA and Lawrence, ML}, title = {Tad pili contribute to the virulence and biofilm formation of virulent Aeromonas hydrophila.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1425624}, pmid = {39145307}, issn = {2235-2988}, mesh = {*Aeromonas hydrophila/genetics/pathogenicity/physiology ; *Biofilms/growth &amp; development ; *Fimbriae, Bacterial/genetics/metabolism ; Virulence/genetics ; Animals ; *Operon ; *Gram-Negative Bacterial Infections/microbiology ; *Fish Diseases/microbiology ; Bacterial Adhesion/genetics ; Catfishes/microbiology ; Bacterial Proteins/genetics/metabolism ; Gene Knockout Techniques ; }, abstract = {Type IV pili (T4P) are versatile proteinaceous protrusions that mediate diverse bacterial processes, including adhesion, motility, and biofilm formation. Aeromonas hydrophila, a Gram-negative facultative anaerobe, causes disease in a wide range of hosts. Previously, we reported the presence of a unique Type IV class C pilus, known as tight adherence (Tad), in virulent Aeromonas hydrophila (vAh). In the present study, we sought to functionalize the role of Tad pili in the pathogenicity of A. hydrophila ML09-119. Through a comprehensive comparative genomics analysis of 170 A. hydrophila genomes, the conserved presence of the Tad operon in vAh isolates was confirmed, suggesting its potential contribution to pathogenicity. Herein, the entire Tad operon was knocked out from A. hydrophila ML09-119 to elucidate its specific role in A. hydrophila virulence. The absence of the Tad operon did not affect growth kinetics but significantly reduced virulence in catfish fingerlings, highlighting the essential role of the Tad operon during infection. Biofilm formation of A. hydrophila ML09-119 was significantly decreased in the Tad operon deletant. Absence of the Tad operon had no effect on sensitivity to other environmental stressors, including hydrogen peroxide, osmolarity, alkalinity, and temperature; however, it was more sensitive to low pH conditions. Scanning electron microscopy revealed that the Tad mutant had a rougher surface structure during log phase growth than the wildtype strain, indicating the absence of Tad impacts the outer surface of vAh during cell division, of which the biological consequences are unknown. These findings highlight the role of Tad in vAh pathogenesis and biofilm formation, signifying the importance of T4P in bacterial infections.}, }
@article {pmid39144210, year = {2024}, author = {Wang, W and Li, Y and Lu, S and Liu, P and Han, X and Sun, W and Wang, Q and Fang, W and Jiang, W}, title = {BolA-like protein (IbaG) promotes biofilm formation and pathogenicity of Vibrio parahaemolyticus.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1436770}, pmid = {39144210}, issn = {1664-302X}, abstract = {Vibrio parahaemolyticus is a gram-negative halophilic bacterium widespread in temperate and tropical coastal waters; it is considered to be the most frequent cause of Vibrio-associated gastroenteritis in many countries. BolA-like proteins, which reportedly affect various growth and metabolic processes including flagellar synthesis in bacteria, are widely conserved from prokaryotes to eukaryotes. However, the effects exerted by BolA-like proteins on V. parahaemolyticus remain unclear, and thus require further investigation. In this study, our purpose was to investigate the role played by BolA-like protein (IbaG) in the pathogenicity of V. parahaemolyticus. We used homologous recombination to obtain the deletion strain ΔibaG and investigated the biological role of BolA family protein IbaG in V. parahaemolyticus. Our results showed that IbaG is a bacterial transcription factor that negatively modulates swimming capacity. Furthermore, overexpressing IbaG enhanced the capabilities of V. parahaemolyticus for swarming and biofilm formation. In addition, inactivation of ibaG in V. parahaemolyticus SH112 impaired its capacity for colonizing the heart, liver, spleen, and kidneys, and reduced visceral tissue damage, thereby leading to diminished virulence, compared with the wild-type strain. Finally, RNA-sequencing revealed 53 upregulated and 71 downregulated genes in the deletion strain ΔibaG. KEGG enrichment analysis showed that the two-component system, quorum sensing, bacterial secretion system, and numerous amino acid metabolism pathways had been altered due to the inactivation of ibaG. The results of this study indicated that IbaG exerts a considerable effect on gene regulation, motility, biofilm formation, and pathogenicity of V. parahaemolyticus. To the best of our knowledge, this is the first systematic study on the role played by IbaG in V. parahaemolyticus infections. Thus, our findings may lead to a better understanding of the metabolic processes involved in bacterial infections and provide a basis for the prevention and control of such infections.}, }
@article {pmid39143645, year = {2024}, author = {Al-Khafaji, NSK and Almjalawi, BSA and Ewadh, RMJ and Al-Dahmoshi, HOM and Abed, SY and Nasrolahi, A and Nwobodo, DC and Kanaan, MHG and Abdullah, SS and Saki, M}, title = {Prevalence of plasmid-mediated quinolone resistance genes and biofilm formation in different species of quinolone-resistant clinical Shigella isolates: a cross-sectional study.}, journal = {European journal of medical research}, volume = {29}, number = {1}, pages = {419}, pmid = {39143645}, issn = {2047-783X}, mesh = {Humans ; *Biofilms/drug effects/growth &amp; development ; Cross-Sectional Studies ; *Quinolones/pharmacology ; *Shigella/genetics/drug effects/isolation &amp; purification ; *Plasmids/genetics ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; Drug Resistance, Bacterial/genetics ; Prevalence ; Dysentery, Bacillary/microbiology/epidemiology/drug therapy ; Female ; }, abstract = {BACKGROUND: The purpose of this study was to look into the presence of plasmid-mediated quinolone resistance (PMQR) genes and biofilm formation in several species of clinical Shigella isolates that were resistant to quinolones.<br><br>METHODS: The stool samples of 150 patients (younger than 10 years) with diarrhea were collected in this cross-sectional study (November 2020 to December 2021). After cultivation of samples on Hektoen Enteric agar and xylose lysine deoxycholate agar, standard microbiology tests, VITEK 2 system, and polymerase chain reaction (PCR) were utilized to identify Shigella isolates. The broth microdilution method was used to determine antibiotic susceptibility. PMQR genes including qnrA, qnrB, qnrC, qnrD, qnrE, qnrS, qnrVC, qepA, oqxAB, aac(6')-Ib-cr, and crpP and biofilm formation were investigated in quinolone-resistant isolates by PCR and microtiter plate method, respectively. An enterobacterial repetitive intergenic consensus polymerase chain reaction (ERIC-PCR) technique was used to determine the clonal relatedness of quinolone-resistant isolates.<br><br>RESULTS: A total of 95 Shigella isolates including S. sonnei (53, 55.8%), S. flexneri (39, 41.1%), and S. boydii (3, 3.2%) were identified. The highest resistance rates of the isolates were against ampicillin (92.6%, n&#x2009;=&#x2009;88/95). Overall, 42 of 95 (44.2%) isolates were simultaneously resistant against two or more quinolones including 26 (61.9%) S. sonnei and 16 (38.1%) S. flexneri. All isolates were multidrug-resistant (resistance to more than 3 antibiotics). The occurrence of PMQR genes was as follows: qnrS (52.4%), qnrA and aac(6')-Ib-cr (33.3%), and qnrB (19.0%). The prevalence in species was as follows: 61.5% and 37.5% (qnrS), 19.2% and 56.3% (qnrA), 38.5% and 25.0 (aac(6')-Ib-cr), and 19.2% and 18.8% (qnrB) for S. sonnei and S. flexneri, respectively. The other PMQR genes were not detected. In total, 52.8% (28/53) of quinolone-susceptible and 64.3% (27/42) of quinolone-resistant isolates were biofilm producers. Biofilm formation was not significantly different between quinolone-resistant and quinolone-susceptible isolates (P-value&#x2009;=&#x2009;0.299). Quinolone-resistant isolates showed a high genetic diversity according to the ERIC-PCR.<br><br>CONCLUSION: It seems that qnrS, qnrA, and aac(6')-Ib-cr play a significant role in the quinolone resistance among Shigella isolates in our region. Also the quinolone-resistant S. flexneri and S. sonnei isolates had a high genetic diversity. Hence, antibiotic therapy needs to be routinely revised based on the surveillance findings.}, }
@article {pmid39143532, year = {2024}, author = {Yang, Y and Fan, L and Jiang, J and Sun, J and Xue, L and Ma, X and Kuai, L and Li, B and Li, Y}, title = {M2 macrophage-polarized anti-inflammatory microneedle patch for accelerating biofilm-infected diabetic wound healing via modulating the insulin pathway.}, journal = {Journal of nanobiotechnology}, volume = {22}, number = {1}, pages = {489}, pmid = {39143532}, issn = {1477-3155}, support = {(No. 82374444//National Natural Science Foundation of China/ ; No. RY411.33.10//Xinglin Youth Scholar of Shanghai University of Traditional Chinese Medicine/ ; (2021-2023//Youth Talent Promotion Project of China Association of Traditional Chinese Medicine/ ; CACM-2021-QNRC2-A10//Category A/ ; 2022YQ026//Health Young Talents of Shanghai Municipal Health Commission/ ; (No. 23YF1439800)//Shanghai Science and Technology Development Funds (Sailing Program)/ ; No. 2023ZZ02017//Shanghai Dermatology Research Center/ ; No. SHDC2023CRW009//Shanghai Skin Disease Hospital demonstration research ward project/ ; (No. 2022XD052)//Talent Program of Shanghai Municipal Health Commission/ ; No. 2021ZD0202003//Sci-Tech Innovation 2030-Major Project of Brain science and brain-inspired intelligence technology/ ; }, mesh = {Animals ; *Wound Healing/drug effects ; *Insulin/metabolism ; Mice ; *Macrophages/metabolism/drug effects ; *Biofilms/drug effects ; *Signal Transduction/drug effects ; *Needles ; Male ; Anti-Inflammatory Agents/pharmacology ; Diabetes Mellitus, Experimental ; Nanoparticles/chemistry ; RAW 264.7 Cells ; Mice, Inbred C57BL ; }, abstract = {Macrophages play a pivotal role in the healing of diabetic ulcers. The sustained elevation of glucose levels damages the insulin signaling pathway in macrophages, leading to dysfunctional macrophages that struggle to transition from pro-inflammatory (M1) to reparative (M2) states. Therefore, modulating macrophage inflammatory responses via the insulin pathway holds promise for diabetic ulcer treatment. Additionally, the presence of biofilm impedes drug penetration, and the resulting immunosuppressive microenvironment exacerbates the persistent infiltration of pro-inflammatory M1 macrophages. Therefore, we designed an array of dissolvable microneedle (denoted as NPF@MN) loaded with self-assembled nanoparticles that could deliver NPF nanoparticles, acid-sensitive NPF-releasing Protocatechualdehyde (PA) with hypoglycemic and insulin-like effects, regulating macrophage polarization to an anti-inflammatory M2 phenotype. Additionally, this study extensively examined the mechanism by which NPF@MN accelerates the healing of diabetic ulcers through the activation of the insulin signaling pathway. Through RNA-seq and GSEA analysis, we identified a reduction in the expression of pathway-related factors such as IR, IRS-1, IRS-2, and SHC. Our work presents an innovative therapeutic approach targeting the insulin pathway in diabetic ulcers and underscores its translational potential for clinical management.}, }
@article {pmid39142478, year = {2024}, author = {Hu, D and Long, D and Xia, T and Wang, Y and Zhang, S and Wang, J and Shi, X and Wang, Y}, title = {Accelerated healing of intractable biofilm-infected diabetic wounds by trypsin-loaded quaternized chitosan hydrogels that disrupt extracellular polymeric substances and eradicate bacteria.}, journal = {International journal of biological macromolecules}, volume = {278}, number = {Pt 2}, pages = {134677}, doi = {10.1016/j.ijbiomac.2024.134677}, pmid = {39142478}, issn = {1879-0003}, mesh = {Hydrogels/chemistry ; *Wound Healing ; *Biofilms ; *Trypsin/analysis/metabolism ; *Chitosan/chemistry ; Extracellular Space/metabolism ; *Diabetes Complications/metabolism/therapy ; Male ; Animals ; Mice ; Rats ; Rats, Sprague-Dawley ; Spectroscopy, Fourier Transform Infrared ; Drug Resistance, Multiple, Bacterial ; Anti-Bacterial Agents/pharmacology ; }, abstract = {Complex and stubborn bacterial biofilm infections significantly hinder diabetic wound healing and threaten public health. Therefore, a dressing material that effectively clears biofilms and promotes wound healing is urgently required. Herein, we introduce a novel strategy for simultaneously dispersing extracellular polymeric substances and eradicating drug-resistant bacteria. We prepared an ultrabroad-spectrum and injectable quaternized chitosan (QCS) hydrogel loaded with trypsin, which degrades biofilm extracellular proteins. Increased temperature initiated QCS gelation to form the hydrogel, enabling the sustained release of trypsin and effective adherence of the hydrogel to irregularly shaped wounds. To reproduce clinical scenarios, biofilms formed by a mixture of Staphylococcus aureus (S. aureus), Methicillin-resistant S. aureus, and Pseudomonas aeruginosa were administered to the wounds of rats with streptozotocin-induced diabetes. Under these severe infection conditions, the hydrogel efficiently suppressed inflammation, promoted angiogenesis, and enhanced collagen deposition, resulting in accelerated healing of diabetic wounds. Notably, the hydrogel demonstrates excellent biocompatibility without cytotoxicity. In summary, we present a trypsin-loaded QCS hydrogel with tremendous clinical applications potential for the treatment of chronic infected wounds.}, }
@article {pmid39142418, year = {2024}, author = {Li, Y and Wang, Q and Chen, H and Song, C and Zheng, Y and Chai, Z and Zheng, M}, title = {Multi-stage oxic biofilm system for pilot-scale treatment of coking wastewater: Pollutants removal performance, biofilm properties and microbial community.}, journal = {Bioresource technology}, volume = {411}, number = {}, pages = {131271}, doi = {10.1016/j.biortech.2024.131271}, pmid = {39142418}, issn = {1873-2976}, mesh = {*Biofilms ; *Wastewater/chemistry ; *Coke ; Water Pollutants, Chemical ; Bioreactors ; Pilot Projects ; Water Purification/methods ; Polyurethanes/chemistry ; Waste Disposal, Fluid/methods ; Biodegradation, Environmental ; Microbiota ; Biomass ; Nitrogen ; Ammonium Compounds ; }, abstract = {A multi-stage oxic biofilm system based on hydrophilic polyurethane foam was established and operated for advanced treatment of coking wastewater, in which distinct gradient variations of pollutants removal, biofilm properties and microbial community in the 5 stages were evaluated. The system rapidly achieved NH4[+]-N removal efficiency of 97.51 ± 2.29 % within 8 days. The biofilm growing attached on the carriers exhibited high biomass (≥10.29 g/L), which ensured sufficient microbial population. Additionally, the rising extracellular polymeric substance and declining proteins/polysaccharides ratios across stages suggested a dense-to-loose transition in the biofilm's structure, in response to the varying pollutant concentrations. The dominance of Nitrosomonas cluster in the first 3 stages and Nitrospira lineage in the following 2 stages facilitated the complete depletion of high NH4[+]-N concentration without NO2[-]-N accumulation. Overall, the distinct biofilm property and community at each stage, shaped by the multi-stage configuration, maximized the pollutants removal efficiency.}, }
@article {pmid39142417, year = {2024}, author = {Wei, CH and Zhai, XY and Jiang, YD and Rong, HW and Zhao, LG and Liang, P and Huang, X and Ngo, HH}, title = {Simultaneous carbon, nitrogen and phosphorus removal in sequencing batch membrane aerated biofilm reactor with biofilm thickness control via air scouring aided by computational fluid dynamics.}, journal = {Bioresource technology}, volume = {409}, number = {}, pages = {131267}, doi = {10.1016/j.biortech.2024.131267}, pmid = {39142417}, issn = {1873-2976}, mesh = {*Biofilms ; *Nitrogen ; *Phosphorus ; *Bioreactors ; *Carbon ; *Hydrodynamics ; *Membranes, Artificial ; Air ; Biological Oxygen Demand Analysis ; Water Purification/methods ; Computer Simulation ; Rheology ; Wastewater/chemistry ; }, abstract = {Membrane aerated biofilm reactor (MABR) is challenged by biofilm thickness control and phosphorus removal. Air scouring aided by computational fluid dynamics (CFD) was employed to detach outer biofilm in sequencing batch MABR treating low C/N wastewater. Biofilm with 177-285 µm thickness in cycle 5-15 achieved over 85 % chemical oxygen demand (COD) and total inorganic nitrogen (TIN) removals at loading rate of 13.2 gCOD/m[2]/d and 2.64 gNH4[+]-N/m[2]/d. Biofilm rheology measurements in cycle 10-25 showed yield stress against detachment of 2.8-7.4 Pa, which were equal to CFD calculated shear stresses under air scouring flowrate of 3-9 L/min. Air scouring reduced effluent NH4[+]-N by 10 % and biofilm thickness by 78 µm. Intermittent aeration (4h off, 19.5h on) and air scouring (3 L/min, 30 s before settling) in one cycle achieved COD removal over 90 %, TIN and PO4[3-]-P removals over 80 %, showing great potential for simultaneous carbon, nitrogen and phosphorus removals.}, }
@article {pmid39141938, year = {2024}, author = {Shi, J and Wan, N and Yang, S and Yang, Y and Han, H}, title = {Which biofilm reactor is suitable for degradation of 2,4-dimethylphenol, focusing on bacteria, algae, or a combination of bacteria-algae?.}, journal = {Journal of hazardous materials}, volume = {478}, number = {}, pages = {135492}, doi = {10.1016/j.jhazmat.2024.135492}, pmid = {39141938}, issn = {1873-3336}, mesh = {*Biofilms/drug effects ; *Bioreactors ; *Water Pollutants, Chemical/metabolism/chemistry ; *Bacteria/metabolism/drug effects ; *Biodegradation, Environmental ; Microalgae/metabolism ; Phenols/metabolism/chemistry ; Chlorella/metabolism/drug effects ; }, abstract = {Effectively treating phenolic substances is a crucial task in environmental protection. This study aims to determine whether bacterial-algae biofilm reactors offer superior treatment efficacy compared to traditional activated sludge and biofilm reactors. The average degradation ratios of 2,4-dimethylphenol (40, 70, 150, 300, and 230 mg/L) were found to be 98 %, 99 %, 92.1 %, 84.7 %, and 63.7 % respectively. The bacterial-algae biofilm demonstrates a higher tolerance to toxicity, assimilation ability, and efficacy recovery ability. The cell membrane of Chlorella in the bacteria-algae biofilm is not easily compromised, thus ensuring a stable pH environment. High concentrations of tightly bound extracellular polymers (TB-EPS) enhance the efficacy in treating toxic pollutants, promote the stable structure. Intact Chlorella, bacilli, and EPS were observed in bacterial-algal biofilm. The structural integrity of bacteria-algae consistently enhances its resistance to the inhibitory effects of high concentrations of phenolic compounds. Cloacibacterium, Comamonas, and Dyella were the main functional bacterial genera that facilitate the formation of bacterial-algal biofilms and the degradation of phenolic compounds. The dominant microalgal families include Aspergillaceae, Chlorellales, Chlorellaceae, and Scenedesmaceae have certain treatment effects on phenolic substances. Chlorellales and Chlorellaceae have the ability to convert NH4[+]-N. The Aspergillaceae is also capable of generating synergistic effects with Chlorellales, Chlorellaceae, and Scenedesmaceae, thereby establishing a stable bacterial-algal biofilm system.}, }
@article {pmid39141525, year = {2024}, author = {Charria-Girón, E and Zeng, H and Gorelik, TE and Pahl, A and Truong, KN and Schrey, H and Surup, F and Marin-Felix, Y}, title = {Arcopilins: A New Family of Staphylococcus aureus Biofilm Disruptors from the Soil Fungus Arcopilus navicularis.}, journal = {Journal of medicinal chemistry}, volume = {67}, number = {17}, pages = {15029-15040}, pmid = {39141525}, issn = {1520-4804}, mesh = {*Biofilms/drug effects ; *Staphylococcus aureus/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Microbial Sensitivity Tests ; Soil Microbiology ; Pyridones/chemistry/pharmacology/chemical synthesis ; Pyrrolidinones/chemistry/pharmacology/metabolism ; }, abstract = {Biofilms represent a key challenge in the treatment of microbial infections; for instance, Staphylococcus aureus causes chronic or fatal infections by forming biofilms on medical devices. Herein, the fungus Arcopilus navicularis was found to produce a novel family of PKS-NRPS metabolites that are able to disrupt preformed biofilms of S. aureus. Arcopilins A-F (1-6), tetramic acids, and arcopilin G (7), a 2-pyridone, were elucidated using HR-ESI-MS and one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) spectroscopy. Their absolute configuration was established by the synthesis of MPTA-esters for 2, analysis of [1]H-[1]H coupling constants, and ROESY correlations, along with comparison with the crystal structure of 7. Arcopilin A (1) not only effectively disrupts preformed biofilms of S. aureus but also potentiates the activity of gentamicin and vancomycin up to 115- and 31-fold times, respectively. Our findings demonstrate the potential application of arcopilins for the conjugated treatment of infections caused by S. aureus with antibiotics unable to disrupt preformed biofilms.}, }
@article {pmid39140783, year = {2024}, author = {Chen, G and Fanouraki, G and Anandhi Rangarajan, A and Winkelman, BT and Winkelman, JT and Waters, CM and Mukherjee, S}, title = {Combinatorial control of Pseudomonas aeruginosa biofilm development by quorum-sensing and nutrient-sensing regulators.}, journal = {mSystems}, volume = {9}, number = {9}, pages = {e0037224}, pmid = {39140783}, issn = {2379-5077}, support = {R35 GM150803/GM/NIGMS NIH HHS/United States ; R00 GM129424/GM/NIGMS NIH HHS/United States ; R35 GM139537/GM/NIGMS NIH HHS/United States ; R00GM129424, R35GM150803//HHS | NIH | National Institute of General Medical Sciences (NIGMS)/ ; SSP-2022-104//Searle Scholars Program (SSP)/ ; R35GM150803,R00GM129424//HHS | NIH | National Institute of General Medical Sciences (NIGMS)/ ; R00GM129424//HHS | NIH | National Institute of General Medical Sciences (NIGMS)/ ; R35GM150803//HHS | NIH | National Institute of General Medical Sciences (NIGMS)/ ; R01 AI158433/AI/NIAID NIH HHS/United States ; R35GM139537//HHS | NIH | National Institute of General Medical Sciences (NIGMS)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Quorum Sensing/genetics ; *Pseudomonas aeruginosa/physiology/genetics ; *Bacterial Proteins/genetics/metabolism ; *Gene Expression Regulation, Bacterial ; Signal Transduction ; Mutation ; Nutrients/metabolism ; Repressor Proteins/genetics/metabolism ; }, abstract = {The human pathogen Pseudomonas aeruginosa, a leading cause of hospital-acquired infections, inhabits and forms sessile antibiotic-resistant communities called biofilms in a wide range of biotic and abiotic environments. In this study, we examined how two global sensory signaling pathways-the RhlR quorum-sensing system and the CbrA/CbrB nutritional adaptation system-intersect to control biofilm development. Previous work has shown that individually these two systems repress biofilm formation. Here, we used biofilm analyses, RNA-seq, and reporter assays to explore the combined effect of information flow through RhlR and CbrA on biofilm development. We find that the ΔrhlRΔcbrA double mutant exhibits a biofilm morphology and an associated transcriptional response distinct from wildtype and the parent ΔrhlR and ΔcbrA mutants indicating codominance of each signaling pathway. The ΔrhlRΔcbrA mutant gains suppressor mutations that allow biofilm expansion; these mutations map to the crc gene resulting in loss of function of the carbon catabolite repression protein Crc. Furthermore, the combined absence of RhlR and CbrA leads to a drastic reduction in the abundance of the Crc antagonist small RNA CrcZ. Thus, CrcZ acts as the molecular convergence point for quorum- and nutrient-sensing cues. We find that in the absence of antagonism by CrcZ, Crc promotes the expression of biofilm matrix components-Pel exopolysaccharide, and CupB and CupC fimbriae. Therefore, this study uncovers a regulatory link between nutritional adaption and quorum sensing with potential implications for anti-biofilm targeting strategies.IMPORTANCEBacteria often form multicellular communities encased in an extracytoplasmic matrix called biofilms. Biofilm development is controlled by various environmental stimuli that are decoded and converted into appropriate cellular responses. To understand how information from two distinct stimuli is integrated, we used biofilm formation in the human pathogen Pseudomonas aeruginosa as a model and studied the intersection of two global sensory signaling pathways-quorum sensing and nutritional adaptation. Global transcriptomics on biofilm cells and reporter assays suggest parallel regulation of biofilms by each pathway that converges on the abundance of a small RNA antagonist of the carbon catabolite repression protein, Crc. We find a new role of Crc as it modulates the expression of biofilm matrix components in response to the environment. These results expand our understanding of the genetic regulatory strategies that allow P. aeruginosa to successfully develop biofilm communities.}, }
@article {pmid39140393, year = {2024}, author = {Basudan, S and Alqahtani, A and Alrwais, F and Almeaither, R and Auda, S and Balto, HA}, title = {Antibiofilm effect of different concentrations of silver nanoparticles combined with calcium hydroxide against Enterococcus faecalis biofilm: An ex vivo study.}, journal = {Australian endodontic journal : the journal of the Australian Society of Endodontology Inc}, volume = {50}, number = {3}, pages = {604-611}, doi = {10.1111/aej.12882}, pmid = {39140393}, issn = {1747-4477}, support = {RSP-2024/179//Researchers Supporting Project, King Saud University/ ; }, mesh = {*Enterococcus faecalis/drug effects ; *Biofilms/drug effects ; *Calcium Hydroxide/pharmacology ; *Silver/pharmacology ; *Metal Nanoparticles ; Humans ; Microscopy, Confocal ; Dentin/drug effects/microbiology ; Anti-Bacterial Agents/pharmacology ; Materials Testing ; Root Canal Irrigants/pharmacology ; }, abstract = {This study aimed to evaluate the antibiofilm activity of different concentrations of silver nanoparticles (AgNPs) in combination with calcium hydroxide [Ca(OH)2] against Enterococcus faecalis biofilm. On an E. faecalis biofilm on dentin discs, the following medicaments were applied for 7 days (n = 13/group): 0.005% AgNPs+Ca(OH)2, 0.01% AgNPs+Ca(OH)2, 0.02% AgNPs + Ca(OH)2, Ca(OH)2 and saline/control. Specimens were stained with LIVE/DEAD® BacLight™ dye and analysed with confocal laser scanning microscopy. Proportion of dead bacteria was calculated and analysed. There was a significant reduction in E. faecalis biofilm in all medicament groups (43.5%, 49.1%, 69.1%, 48.7%) respectively, compared with control group (2.54%) (p < 0.001). The 0.02% AgNPs + Ca(OH)2 group demonstrated the most significantly superior antibiofilm effect, with no significant difference between remaining groups. In conclusion, combining 0.02% AgNPs enhanced the antibiofilm effect of Ca(OH)2 on E. faecalis biofilm compared with lower AgNPs concentrations.}, }
@article {pmid39140129, year = {2024}, author = {Manobala, T}, title = {Peptide-based strategies for overcoming biofilm-associated infections: a comprehensive review.}, journal = {Critical reviews in microbiology}, volume = {}, number = {}, pages = {1-18}, doi = {10.1080/1040841X.2024.2390597}, pmid = {39140129}, issn = {1549-7828}, abstract = {Biofilms represent resilient microbial communities responsible for inducing chronic infections in human subjects. Given the escalating challenges associated with antibiotic therapy failures in clinical infections linked to biofilm formation, a peptide-based approach emerges as a promising alternative to effectively combat these notoriously resistant biofilms. Contrary to conventional antimicrobial peptides, which predominantly target cellular membranes, antibiofilm peptides necessitate a multifaceted approach, addressing various "biofilm-specific factors." These factors encompass Extracellular Polymeric Substance (EPS) degradation, membrane targeting, cell signaling, and regulatory mechanisms. Recent research endeavors have been directed toward assessing the potential of peptides as potent antibiofilm agents. However, to translate these peptides into viable clinical applications, several critical considerations must be meticulously evaluated during the peptide design process. This review serves to furnish an all-encompassing summary of the pivotal factors and parameters that necessitate contemplation for the successful development of an efficacious antibiofilm peptide.}, }
@article {pmid39139372, year = {2024}, author = {Diaz-Mateus, MA and Salgar-Chaparro, SJ and Tarazona, J and Farhat, H}, title = {Exploring the influence of deposit mineral composition on biofilm communities in oil and gas systems.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1438806}, pmid = {39139372}, issn = {1664-302X}, abstract = {INTRODUCTION: Inside oil and gas pipelines, native microbial communities and different solid compounds typically coexist and form mixed deposits. However, interactions between these deposits (primarily consisting of mineral phases) and microorganisms in oil and gas systems remain poorly understood. Here, we investigated the influence of magnetite (Fe3O4), troilite (FeS), and silica (SiO2) on the microbial diversity, cell viability, biofilm formation, and EPS composition of an oil-recovered multispecies consortium.<br><br>METHODS: An oilfield-recovered microbial consortium was grown for 2 weeks in separate bioreactors, each containing 10&#x2009;g of commercially available magnetite (Fe3O4), troilite (FeS), or silica (SiO2) at 40&#xb0;C&#x2009;&#xb1;&#x2009;1&#xb0;C under a gas atmosphere of 20% CO2/80% N2.<br><br>RESULTS: The microbial population formed in troilite significantly differed from those in silica and magnetite, which exhibited significant similarities. The dominant taxa in troilite was the Dethiosulfovibrio genus, whereas Sulfurospirillum dominated in magnetite and silica. Nevertheless, biofilm formation was lowest on troilite and highest on silica, correlating with the observed cell viability.<br><br>DISCUSSION: The dissolution of troilite followed by the liberation of HS[-] (H2S) and Fe[2+] into the test solution, along with its larger particle size compared to silica, likely contributed to the observed results. Confocal laser scanning microscopy revealed that the EPS of the biofilm formed in silica was dominated by eDNA, while those in troilite and magnetite primarily contained polysaccharides. Although the mechanisms of this phenomenon could not be determined, these findings are anticipated to be particularly valuable for enhancing MIC mitigation strategies currently used in oil and gas systems.}, }
@article {pmid39139360, year = {2024}, author = {Roscetto, E and Di Gennaro, D and Ascione, T and Galdiero, U and Aversa, M and Festa, E and Catania, MR and Balato, G}, title = {Antiseptics' Concentration, Combination, and Exposure Time on Bacterial and Fungal Biofilm Eradication.}, journal = {Arthroplasty today}, volume = {28}, number = {}, pages = {101468}, pmid = {39139360}, issn = {2352-3441}, abstract = {BACKGROUND: This study aims to assess the activity of solutions containing povidone-iodine (PI) and hydrogen peroxide (H2O2) alone or combined on the biofilm of microbial species in the contest of periprosthetic joint infection (PJI).<br><br>METHODS: Different antiseptic solutions were tested on 2-day-old biofilms of Gram-positive and Gram-negative bacteria and fungi at 1 and 3 minutes of exposure. The efficacy of these solutions was evaluated by measuring the biofilm metabolic activity by methoxynitrosulfophenyl-tetrazolium carboxanilide (XTT) reduction assay. The anti-biofilm effect of 5% PI and 0.3% PI&#xa0;+ 0.5% H2O2 was tested on a 5-day-old biofilm using colony-forming unit counts and an XTT reduction assay.<br><br>RESULTS: PI and H2O2 solutions showed concentration-dependent anti-biofilm activity except for E.&#xa0;faecalis. PI at 5% was the most active solution against the 2-day-old biofilm of all test microorganisms. The 0.3% PI&#xa0;+ 0.5% H&#x2082;O&#x2082; solution had a significant effect only at 3 minutes. The 5% PI and 0.3% PI&#xa0;+ 0.5% H&#x2082;O&#x2082; effect was evaluated on 5-day-old biofilms. PI at 5% produced a significant reduction in metabolic activity at both 1 and 3 minutes; 0.3% PI&#xa0;+ 0.5% H&#x2082;O&#x2082; caused a significant activity against all Gram-positive strains after 3 minutes, with a greater metabolic activity reduction than 5% PI.<br><br>CONCLUSIONS: In the case of PJI caused by Gram-positive bacteria, 0.3% PI&#xa0;+ 0.5% H&#x2082;O&#x2082; could be used for wound irrigation for 3 minutes of exposure. In the case of PJI with a different etiological agent or PJI with an unknown etiology, it is advisable to use 5% PI for 1 minute of exposure.}, }
@article {pmid39138881, year = {2024}, author = {Pathoor, NN and Ganesh, PS}, title = {Reply to "Comment on micro- and nanorobots for biofilm eradication".}, journal = {APMIS : acta pathologica, microbiologica, et immunologica Scandinavica}, volume = {132}, number = {11}, pages = {757-758}, doi = {10.1111/apm.13460}, pmid = {39138881}, issn = {1600-0463}, }
@article {pmid39137519, year = {2024}, author = {Köksaldı, &#x130;&#xc7; and Avcı, E and Köse, S and Özkul, G and Kehribar, E&#x15e; and Şafak Şeker, U&#xd6;}, title = {Genetically engineered bacterial biofilm materials enhances portable whole cell sensing.}, journal = {Biosensors &amp; bioelectronics}, volume = {264}, number = {}, pages = {116644}, doi = {10.1016/j.bios.2024.116644}, pmid = {39137519}, issn = {1873-4235}, mesh = {*Biosensing Techniques/instrumentation/methods ; *Biofilms ; *Escherichia coli/isolation &amp; purification ; *Copper/chemistry ; *Escherichia coli Proteins/genetics/chemistry ; Genetic Engineering ; Paper ; Environmental Monitoring/instrumentation ; }, abstract = {In recent years, whole-cell biosensors (WCBs) have emerged as a potent approach for environmental monitoring and on-site analyte detection. These biosensors harness the biological apparatus of microorganisms to identify specific analytes, offering advantages in sensitivity, specificity, and real-time monitoring capabilities. A critical hurdle in biosensor development lies in ensuring the robust attachment of cells to surfaces, a crucial step for practical utility. In this study, we present a comprehensive approach to tackle this challenge via engineering Escherichia coli cells for immobilization on paper through the Curli biofilm pathway. Furthermore, incorporating a cellulose-binding peptide domain to the CsgA biofilm protein enhances cell adhesion to paper surfaces, consequently boosting biosensor efficacy. To demonstrate the versatility of this platform, we developed a WCB for copper, optimized to exhibit a discernible response, even with the naked eye. To confirm its suitability for practical field use, we characterized our copper sensor under various environmental conditions-temperature, salinity, and pH-to mimic real-world scenarios. The biosensor-equipped paper discs can be freeze-dried for deployment in on-site applications, providing a practical method for long-term storage without loss of sensitivity paper discs demonstrate sustained functionality and viability even after months of storage with 5 μM limit of detection for copper with visible-to-naked-eye signal levels. Biofilm-mediated surface attachment and analyte sensing can be independently engineered, allowing for flexible utilization of this platform as required. With the implementation of copper sensing as a proof-of-concept study, we underscore the potential of WCBs as a promising avenue for the on-site detection of a multitude of analytes.}, }
@article {pmid39137468, year = {2024}, author = {Tian, LL and Li, Y and Yang, R and Jiang, Y and He, JJ and Wang, H and Chen, LQ and Zhu, WY and Xue, T and Li, BB}, title = {Low concentrations of tetrabromobisphenol A promote the biofilm formation of methicillin-resistant Staphylococcus aureus.}, journal = {Ecotoxicology and environmental safety}, volume = {283}, number = {}, pages = {116853}, doi = {10.1016/j.ecoenv.2024.116853}, pmid = {39137468}, issn = {1090-2414}, mesh = {*Biofilms/drug effects ; *Methicillin-Resistant Staphylococcus aureus/drug effects/physiology ; *Polybrominated Biphenyls/toxicity ; Xanthophylls ; Bacterial Proteins/genetics ; }, abstract = {The effect and underlying mechanism of tetrabromobisphenol A (TBBPA), a plastic additive, on biofilm formation of methicillin-resistant Staphylococcus aureus (MRSA USA300) remain unknown. This study first investigated the impact of different concentrations of TBBPA on the growth and biofilm formation of USA300. The results indicated that a low concentration (0.5 mg/L) of TBBPA promoted the growth and biofilm formation of USA300, whereas high concentrations (5 mg/L and 10 mg/L) of TBBPA had inhibitory effects. Further exploration revealed that the low concentration of TBBPA enhance biofilm formation by promoting the synthesis of extracellular proteins, release of extracellular DNA (eDNA), and production of staphyloxanthin. RTqPCR analysis demonstrated that the low concentration of TBBPA upregulated genes associated with extracellular protein synthesis (sarA, fnbA, fnbB, aur) and eDNA formation (atlA) and increased the expression of genes involved in staphyloxanthin biosynthesis (crtM), suggesting a potential mechanism for enhanced resistance of USA300 to adverse conditions. These findings shed light on how low concentrations of TBBPA facilitate biofilm formation in USA300 and highlight the indirect impact of plastic additives on pathogenic bacteria in terms of human health. In the future, in-depth studies about effects of plastic additives on pathogenicity of pathogenic bacteria should be conducted. CAPSULE: The protein and eDNA contents in biofilms of methicillin-resistant Staphylococcus aureus are increased by low concentrations of TBBPA.}, }
@article {pmid39135871, year = {2024}, author = {Saini, P and Ayyanna, R and Kumar, R and Bhowmick, SK and Bhaskar, V and Dey, B}, title = {Restriction of growth and biofilm formation of ESKAPE pathogens by caprine gut-derived probiotic bacteria.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1428808}, pmid = {39135871}, issn = {1664-302X}, abstract = {The accelerated rise in antimicrobial resistance (AMR) poses a significant global health risk, necessitating the exploration of alternative strategies to combat pathogenic infections. Biofilm-related infections that are unresponsive to standard antibiotics often require the use of higher-order antimicrobials with toxic side effects and the potential to disrupt the microbiome. Probiotic therapy, with its diverse benefits and inherent safety, is emerging as a promising approach to prevent and treat various infections, and as an alternative to antibiotic therapy. In this study, we isolated novel probiotic bacteria from the gut of domestic goats (Capra hircus) and evaluated their antimicrobial and anti-biofilm activities against the 'ESKAPE' group of pathogens. We performed comprehensive microbiological, biochemical, and molecular characterizations, including analysis of the 16S-rRNA gene V1-V3 region and the 16S-23S ISR region, on 20 caprine gut-derived lactic acid bacteria (LAB). Among these, six selected Lactobacillus isolates demonstrated substantial biofilm formation under anaerobic conditions and exhibited robust cell surface hydrophobicity and autoaggregation, and epithelial cell adhesion properties highlighting their superior enteric colonization capability. Notably, these Lactobacillus isolates exhibited broad-spectrum growth inhibitory and anti-biofilm properties against 'ESKAPE' pathogens. Additionally, the Lactobacillus isolates were susceptible to antibiotics listed by the European Food Safety Authority (EFSA) within the prescribed Minimum Inhibitory Concentration limits, suggesting their safety as feed additives. The remarkable probiotic characteristics exhibited by the caprine gut-derived Lactobacillus isolates in this study strongly endorse their potential as compelling alternatives to antibiotics and direct-fed microbial (DFM) feed supplements in the livestock industry, addressing the escalating need for antibiotic-free animal products.}, }
@article {pmid39135331, year = {2024}, author = {Gaihre, S and Prajapati, K and Dhungel, S and Dawadi, P and Joshi, DR and Joshi, TP}, title = {Occurrence of biofilm forming Escherichia coli in drinking water supply system in Kathmandu.}, journal = {Water environment research : a research publication of the Water Environment Federation}, volume = {96}, number = {8}, pages = {e11096}, doi = {10.1002/wer.11096}, pmid = {39135331}, issn = {1554-7531}, support = {//Nepal Academy of Science and Technology/ ; 4500406708//UNESCO and the International Development Research Center (IDRC)/ ; }, mesh = {*Biofilms ; *Escherichia coli/genetics/drug effects/physiology/isolation &amp; purification ; Nepal ; *Drinking Water/microbiology ; *Water Supply ; Anti-Bacterial Agents/pharmacology ; Microbial Sensitivity Tests ; Water Microbiology ; }, abstract = {Biofilm development in gram negative bacterial contaminants in water supply systems is linked to persistence as well as antibiotic resistance, which threatens water quality and hence the public health. This study aimed to investigate phenotypic and genetic capacity of biofilm formation by Escherichia coli isolated from supply water with their antibiotic susceptibility pattern. Altogether fifty water samples collected from a city supply water distribution scheme in Kathmandu were analyzed to assess the physicochemical and microbiological quality. Comparing Nepal's national drinking water quality standards 2022, conductivity (4%), turbidity (18%), iron (28%), and residual chlorine (8%) were found exceeding the values above the standards. Among total, 40% of water samples were contaminated with total coliform bacteria. E. coli and Citrobacter species were dominant and isolated from 20 (64.52%) and 11 (35.48%) water samples, respectively. Antibiotic susceptibility testing revealed that E. coli isolates were resistant to ampicillin (20%), nitrofurantoin (10%), and cefotaxime (10%). Citrobacter spp. (54.54%) were found multidrug resistant (MDR) while none of the isolates of E. coli were MDR. Of total, 45% of the isolates developed biofilm while testing with the Microtiter plate method. Biofilm-forming genes bcsA and csgD in E. coli isolates were detected with polymerase chain reaction (PCR) employing specific primers. bcsA and csgD genes were detected in 55% and 45% of the isolates, respectively. This study confirms the occurrences of biofilm forming and antibiotic resistant bacteria like E. coli in the drinking water supply system in Kathmandu alarming its environmental circulation and possible public health threat. Although further study is warranted, this study suggests public health and drinking water treatment interventions to mitigate the biofilm forming antibiotic resistant potential pathogens from supply water in Kathmandu, Nepal. PRACTITIONER POINTS: Forty percent of tested drinking water samples in Kathmandu were contaminated with total coliform bacteria. E. coli and half of Citrobacter spp. isolates were resistant to multiple antibiotics. bcsA and csgD genes were detected in biofilm producing E.coli isolates.}, }
@article {pmid39135304, year = {2024}, author = {Yeung, YWS and Ma, Y and Deng, Y and Khoo, BL and Chua, SL}, title = {Bacterial Iron Siderophore Drives Tumor Survival and Ferroptosis Resistance in a Biofilm-Tumor Spheroid Coculture Model.}, journal = {Advanced science (Weinheim, Baden-Wurttemberg, Germany)}, volume = {11}, number = {39}, pages = {e2404467}, pmid = {39135304}, issn = {2198-3844}, mesh = {*Ferroptosis/drug effects ; *Biofilms/drug effects ; Humans ; *Pseudomonas aeruginosa/drug effects/metabolism ; *Siderophores/metabolism/pharmacology ; *Spheroids, Cellular/metabolism/drug effects ; Tumor Microenvironment/drug effects ; Coculture Techniques ; Cell Survival/drug effects ; Cell Line, Tumor ; Lung Neoplasms/metabolism/drug therapy/pathology ; Iron/metabolism ; Oligopeptides/pharmacology/metabolism ; }, abstract = {Interactions between tumoral cells and tumor-associated bacteria within the tumor microenvironment play a significant role in tumor survival and progression, potentially impacting cancer treatment outcomes. In lung cancer patients, the Gram-negative pathogen Pseudomonas aeruginosa raises questions about its role in tumor survival. Here, a microfluidic-based 3D-human lung tumor spheroid-P. aeruginosa model is developed to study the bacteria's impact on tumor survival. P. aeruginosa forms a tumor-associated biofilm by producing Psl exopolysaccharide and secreting iron-scavenging pyoverdine, which is critical for establishing a bacterial community in tumors. Consequently, pyoverdine promotes cancer progression by reducing susceptibility to iron-induced death (ferroptosis), enhancing cell viability, and facilitating several cancer hallmarks, including epithelial-mesenchymal transition and metastasis. A promising combinatorial therapy approach using antimicrobial tobramycin, ferroptosis-inducing thiostrepton, and anti-cancer doxorubicin could eradicate biofilms and tumors. This work unveils a novel phenomenon of cross-kingdom cooperation, where bacteria protect tumors from death, and it paves the way for future research in developing antibiofilm cancer therapies. Understanding these interactions offers potential new strategies for combatting cancer and enhancing treatment efficacy.}, }
@article {pmid39133525, year = {2024}, author = {Scharnow, AM and Solinski, AE and Rowe, S and Drechsel, I and Zhang, H and Shaw, E and Page, JE and Wu, H and Sieber, SA and Wuest, WM}, title = {In Situ Biofilm Affinity-Based Protein Profiling Identifies the Streptococcal Hydrolase GbpB as the Target of a Carolacton-Inspired Chemical Probe.}, journal = {Journal of the American Chemical Society}, volume = {146}, number = {33}, pages = {23449-23456}, pmid = {39133525}, issn = {1520-5126}, support = {R01 AI149778/AI/NIAID NIH HHS/United States ; T32 GM007753/GM/NIGMS NIH HHS/United States ; R35 GM119426/GM/NIGMS NIH HHS/United States ; R01 DE025837/DE/NIDCR NIH HHS/United States ; R01 AI148752/AI/NIAID NIH HHS/United States ; T90 DE030859/DE/NIDCR NIH HHS/United States ; R01 DE022350/DE/NIDCR NIH HHS/United States ; }, mesh = {*Biofilms/drug effects ; Bacterial Proteins/metabolism/chemistry ; Anti-Bacterial Agents/pharmacology/chemistry ; Molecular Probes/chemistry/metabolism ; N-Acetylmuramoyl-L-alanine Amidase/metabolism/chemistry ; Lactones/chemistry/metabolism/pharmacology ; Hydrolases/metabolism/chemistry/antagonists &amp; inhibitors ; }, abstract = {Natural products are important precursors for antibiotic drug design. These chemical scaffolds serve as synthetic inspiration for chemists who leverage their structures to develop novel antibacterials and chemical probes. We have previously studied carolacton, a natural product macrolactone fromSorangium cellulosum, and discovered a simplified derivative, A2, that maintained apparent biofilm inhibitory activity, although the biological target was unknown. Herein, we utilize affinity-based protein profiling (AfBPP) in situ during biofilm formation to identify the protein target using a photoexcitable cross-linking derivative of A2. From these studies, we identified glucan binding protein B (GbpB), a peptidoglycan hydrolase, as the primary target of A2. Further characterization of the interaction between A2 and GbpB, as well as PcsB, a closely related homologue from the more pathogenic S. pneumoniae, revealed binding to the catalytic CHAP (cysteine, histidine, aminopeptidase) domain. To the best of our knowledge, this is the first report of a small-molecule binder of a conserved and essential bacterial CHAP hydrolase, revealing its potential as an antibiotic target. This work also highlights A2 as a useful tool compound for streptococci and as an initial scaffold for the design of more potent CHAP binders.}, }
@article {pmid39133016, year = {2024}, author = {Albicoro, FJ and Bessho, S and Grando, K and Olubajo, S and Tam, V and Tükel, &#xc7;}, title = {Lactate promotes the biofilm-to-invasive-planktonic transition in Salmonella enterica serovar Typhimurium via the de novo purine pathway.}, journal = {Infection and immunity}, volume = {92}, number = {10}, pages = {e0026624}, pmid = {39133016}, issn = {1098-5522}, support = {R01 AI153325/AI/NIAID NIH HHS/United States ; R01 AI168550/AI/NIAID NIH HHS/United States ; R01 AI171568/AI/NIAID NIH HHS/United States ; }, mesh = {*Biofilms/growth &amp; development ; *Salmonella typhimurium/metabolism/physiology/genetics ; *Lactic Acid/metabolism ; *Purines/metabolism ; *Gene Expression Regulation, Bacterial ; Mice ; Bacterial Proteins/metabolism/genetics ; Animals ; Salmonella Infections/microbiology/metabolism ; Cyclic GMP/metabolism/analogs &amp; derivatives ; Virulence ; }, abstract = {Salmonella enterica serovar Typhimurium (S. Typhimurium) infection triggers an inflammatory response that changes the concentration of metabolites in the gut impacting the luminal environment. Some of these environmental adjustments are conducive to S. Typhimurium growth, such as the increased concentrations of nitrate and tetrathionate or the reduced levels of Clostridia-produced butyrate. We recently demonstrated that S. Typhimurium can form biofilms within the host environment and respond to nitrate as a signaling molecule, enabling it to transition between sessile and planktonic states. To investigate whether S. Typhimurium utilizes additional metabolites to regulate its behavior, our study delved into the impact of inflammatory metabolites on biofilm formation. The results revealed that lactate, the most prevalent metabolite in the inflammatory environment, impedes biofilm development by reducing intracellular c-di-GMP levels, suppressing the expression of curli and cellulose, and increasing the expression of flagellar genes. A transcriptomic analysis determined that the expression of the de novo purine pathway increases during high lactate conditions, and a transposon mutagenesis genetic screen identified that PurA and PurG, in particular, play a significant role in the inhibition of curli expression and biofilm formation. Lactate also increases the transcription of the type III secretion system genes involved in tissue invasion. Finally, we show that the pyruvate-modulated two-component system BtsSR is activated in the presence of high lactate, which suggests that lactate-derived pyruvate activates BtsSR system after being exported from the cytosol. All these findings propose that lactate is an important inflammatory metabolite used by S. Typhimurium to transition from a biofilm to a motile state and fine-tune its virulence.IMPORTANCEWhen colonizing the gut, Salmonella enterica serovar Typhimurium (S. Typhimurium) adopts a dynamic lifestyle that alternates between a virulent planktonic state and a multicellular biofilm state. The coexistence of biofilm formers and planktonic S. Typhimurium in the gut suggests the presence of regulatory mechanisms that control planktonic-to-sessile transition. The signals triggering the transition of S. Typhimurium between these two lifestyles are not fully explored. In this work, we demonstrated that in the presence of lactate, the most dominant host-derived metabolite in the inflamed gut, there is a reduction of c-di-GMP in S. Typhimurium, which subsequently inhibits biofilm formation and induces the expression of its invasion machinery, motility genes, and de novo purine metabolic pathway genes. Furthermore, high levels of lactate activate the BtsSR two-component system. Collectively, this work presents new insights toward the comprehension of host metabolism and gut microenvironment roles in the regulation of S. Typhimurium biology during infection.}, }
@article {pmid39132636, year = {2024}, author = {Rouamba, A and Badini, D and Compaoré, E and Ouédraogo, V and Kiendrebeogo, M}, title = {Lippia multiflora Leaves Extracts Enhance Cefotaxime Bactericidal Effects and Quench the Biofilm Formation in Methicillin-Resistant Staphylococcus aureus ATCC 43300.}, journal = {Avicenna journal of medical biotechnology}, volume = {16}, number = {3}, pages = {193-199}, pmid = {39132636}, issn = {2008-2835}, abstract = {BACKGROUND: The emergence of the multidrug-resistant bacteria strain has become a global world crisis. This study was designed to evaluate the antibiofilm and synergistic effects of Lippia multiflora leaf extracts on the activity of cefotaxime against the methicillin-resistant Staphylococcus aureus (S. aureus).<br><br>METHODS: The synergistic effect of methanol and dichloromethane extracts on the bactericidal activity of cefotaxime was determined by using the antibiotic susceptibility test on agar medium. The antibiofilm activity of the extracts was measured by using the crystal violet method. The antioxidant potential of the extracts was assessed by using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Ferric Reduction Activity Potential (FRAP) methods. The main secondary metabolites groups were analyzed by using different standard analytical tests. The total phenolics and total flavonoids were quantified spectrophotometrically.<br><br>RESULTS: The methanol extract (final concentration of 100 &#x3bc;g/ml) inhibited the formation of bacterial biofilm more than salicylic acid (p<0.05). All extracts combined with cefotaxime (20 &#x3bc;g and 200 &#x3bc;g) showed good synergistic bactericidal effect on S. aureus with inhibitory diameters of up to 40 mm. The methanol extract showed higher total phenolics (462.20&#xb1;10.90 mg EAG/g) and total flavonoids (26.20&#xb1;0.20 mg EQ/g) contents than the dichloromethane extract (96.70&#xb1;1.70 mg EAG/g and 8.00&#xb1;1.20 mg EQ/g). Moreover, the methanol extract showed a higher FRAP reducing power (353.6&#xb1;4.17 mmol EQ/g) than the dichloromethane extract (385.3&#xb1;7.01 mmol EQ/g). Qualitative phytochemical analysis showed the presence of tannins, flavonoids, terpenes and sterols in both extracts.<br><br>CONCLUSION: These data showed that L. multiflora leaves contain effective antibacterial phytomolecules for combating bacterial resistance.}, }
@article {pmid39127970, year = {2024}, author = {Chai, Y and Ma, Q and He, J and Wei, G and Huang, A}, title = {Rapid Revealing of Quorum Sensing (QS)-Regulated PLA, Biofilm and Lysine Targets of Lactiplantibacillus plantarum L3.}, journal = {Current microbiology}, volume = {81}, number = {10}, pages = {303}, pmid = {39127970}, issn = {1432-0991}, support = {No. 32260578//National Natural Science Foundation of China/ ; 202302AN360002//Yunnan Province-City Integration Project/ ; }, mesh = {*Quorum Sensing ; *Bacterial Proteins/genetics/metabolism ; *Biofilms/growth &amp; development ; *Gene Expression Regulation, Bacterial ; *Lysine/metabolism ; Lactobacillus plantarum/genetics/metabolism/physiology ; Genome, Bacterial ; Carbon-Sulfur Lyases ; }, abstract = {Quorum sensing (QS) can regulate the production of multiple functional factors in bacteria, but the process of identifying its regulatory targets is very complex and labor-intensive. In this study, an efficient and rapid method to find QS targets through prediction was used. The genome of Lactiplantibacillus plantarum (L. plantarum) L3 was sequenced and characterized, and then linked the L. plantarum L3 genome to the STRING database for QS system regulatory target prediction. A total of 3,167,484 base pairs (bps) were examined from the genome of L. plantarum L3, and 30 QS-related genes were discovered (including luxS). The STRING database prediction indicated that the 30 QS-related genes are mainly involved in the regulation of nine metabolic pathways. Furthermore, metE, metK, aroB, cysE, and birA1 were predicted to be regulatory targets of the LuxS/AI-2 QS system, and these five targets were validated based on quantitative real-time PCR and content determination. Successful elucidation of the LuxS/AI-2 QS system's key targets and regulation mechanism in L. plantarum L3 demonstrated the effectiveness of the new approach for predicting QS targets and provides a scientific basis for future work on improving regulation of functional factor production.}, }
@article {pmid39127666, year = {2024}, author = {Wang, H and Fan, Q and Wang, Y and Yi, L and Wang, Y}, title = {Multi-omics analysis reveals genes and metabolites involved in Streptococcus suis biofilm formation.}, journal = {BMC microbiology}, volume = {24}, number = {1}, pages = {297}, pmid = {39127666}, issn = {1471-2180}, support = {222300420005//Excellent Youth Foundation of He'nan Scientific Committee/ ; 232102110095//Henan Provincial Science and Technology Research Project/ ; 24IRTSTHN033//Program for Innovative Research Team (in Science and Technology) in University of Henan Province/ ; (24A230013)//Key Scientific Research Projects of Universities in Henan Province/ ; 32172852//the National Natural Science Foundation of China/ ; }, mesh = {Bacterial Proteins/genetics/metabolism ; *Biofilms/growth &amp; development ; Gene Expression Profiling ; Gene Expression Regulation, Bacterial ; Metabolic Networks and Pathways/genetics ; Metabolome ; Metabolomics ; Multiomics ; *Streptococcus suis/genetics/metabolism ; Transcriptome ; }, abstract = {BACKGROUND: Streptococcus suis is an important zoonotic pathogen. Biofilm formation largely explains the difficulty in preventing and controlling S. suis. However, little is known about the molecular mechanism of S. suis biofilm formation.<br><br>RESULTS: In this study, transcriptomic and metabolomic analyses of S. suis in biofilm and planktonic states were performed to identify key genes and metabolites involved in biofilm formation. A total of 789 differential genes and 365 differential metabolites were identified. By integrating transcriptomics and metabolomics, five main metabolic pathways were identified, including amino acid pathway, nucleotide metabolism pathway, carbon metabolism pathway, vitamin and cofactor metabolism pathway, and aminoacyl-tRNA biosynthesis metabolic pathway.<br><br>CONCLUSIONS: These results provide new insights for exploring the molecular mechanism of S. suis biofilm formation.}, }
@article {pmid39127090, year = {2024}, author = {Swidsinski, A and Amann, R and Guschin, A and Swidsinski, S and Loening-Baucke, V and Mendling, W and Sobel, JD and Lamont, RF and Vaneechoutte, M and Baptista, PV and Bradshaw, CS and Kogan, IY and Savicheva, &#x410;M and Mitrokhin, OV and Swidsinski, NW and Sukhikh, GT and Priputnevich, TV and Apolikhina, IA and Dörffel, Y}, title = {Polymicrobial consortia in the pathogenesis of biofilm vaginosis visualized by FISH. Historic review outlining the basic principles of the polymicrobial infection theory.}, journal = {Microbes and infection}, volume = {26}, number = {8}, pages = {105403}, doi = {10.1016/j.micinf.2024.105403}, pmid = {39127090}, issn = {1769-714X}, mesh = {Humans ; Female ; *Vaginosis, Bacterial/microbiology ; *In Situ Hybridization, Fluorescence ; *Biofilms/growth &amp; development ; Vagina/microbiology ; Coinfection/microbiology ; Microbial Consortia ; Bacteria/genetics/pathogenicity/classification/isolation &amp; purification ; Male ; Microbiota ; }, abstract = {The manuscript disputes the exclusive mono-infectious way of thinking, which presumes that for every infection only one pathogen is responsible and sufficient, when infectious vectors, close contact and reduced immunity meet. In situations involving heavily colonized anatomical sites such an approach often ends in insoluble contradictions. Upon critical reflection and evaluation of 20 years research on spatial organization of vaginal microbiota it is apparent, that in some situations, pathogens may act and operate in permanent, structurally organized consortia, whereas its individual components may be innocuous and innocent, failing to express any pathogenic effect. In these cases, consortia are the true pathogens responsible for many infectious conditions, which usually remain unrecognized as long as improperly diagnosed. The structure of such consortia can be unraveled using ribosomal fluorescence in situ hybridization (FISH). FISH methodology, that not only offers an ex vivo opportunity to recognize bacterial species, but provides unique physical insight into their specific role in the pathogenesis of polymicrobial infections. Ribosomal FISH technique applied to both, women with bacterial vaginosis (BV) and their male partners, has added significantly to our understanding of the pathogenesis of this condition and contributed to appreciating the mechanisms of polymicrobial, community-based infection, potentially leading to therapeutic advances.}, }
@article {pmid39126743, year = {2024}, author = {Song, D and Wang, L and Sun, W and Zhang, Y and Xie, B and Zhao, Y and Wang, W and Wang, P and Ma, J and Cheng, W}, title = {Tourmaline triggered biofilm transformation: Boosting ultrafiltration efficiency and fouling resistance.}, journal = {Water research}, volume = {264}, number = {}, pages = {122212}, doi = {10.1016/j.watres.2024.122212}, pmid = {39126743}, issn = {1879-2448}, mesh = {*Biofilms ; *Ultrafiltration ; *Biofouling ; *Water Purification/methods ; *Membranes, Artificial ; }, abstract = {Ultralow pressure filtration system, which integrates the dual functionalities of biofilm degradation and membrane filtration, has gained significant attention in water treatment due to its superior contaminant removal efficiency. However, it is a challenge to mitigate membrane biofouling while maintaining the high activity of biofilm. This study presents a novel ceramic-based ultrafiltration membrane functionalized with tourmaline nanoparticles to address this challenge. The incorporation of tourmaline nanoparticles enables the release of nutrient elements and the generation of an electric field, which enhances the biofilm activity on the membrane surface and simultaneously alleviates intrapore biofouling. The tourmaline-modified ceramic membrane (TCM) demonstrated a significant antifouling effect, with a substantial increase in water flux by 60 %. Additionally, the TCM achieved high removal efficiencies for contaminants (48.78 % in TOC, 22.28 % in UV254, and 24.42 % in TN) after 30 days of continuous operation. The fouling resistance by various constituents in natural water was individually analyzed using model compounds. The TCM with improved electronegativity and hydrophilicity exhibited superior resistance to irreversible fouling through increased electrostatic repulsion and reduced adhesion to foulants. Comprehensive characterizations and analyses, including interfacial interaction energies, redox reaction processes, and biofilm evolutions, demonstrated that the TCM can release nutrient elements to facilitate the development of functional microbial community within the biofilm, and generate reactive oxygen species (ROS) on the membrane surface to the degrade contaminants and mitigate membrane biofouling. The electric field generated by tourmaline nanoparticles can promote electron transfer in the Fe(III)/Fe(II) cycle, ensuring a stable and sustainable generation of ROS and bactericidal negative ions. These synergistic functions enhance contaminant removal and reduce irreversible fouling of the TCM. This study provides fundamental insights into the role of tourmaline-modified surfaces in enhancing membrane filtration performance and fouling resistance, inspiring the development of high-performance, anti-fouling membranes.}, }
@article {pmid39126548, year = {2024}, author = {Zaytsev, EM and Britsina, MV and Ozeretskovskaya, MN and Zaitsev, AE}, title = {Protective Activity and Safety of Experimental Acellular Pertussis Vaccines Based on Antigenic Complexes Isolated from Biofilm and Planktonic Cultures of Bordetella pertussis.}, journal = {Bulletin of experimental biology and medicine}, volume = {177}, number = {3}, pages = {349-352}, pmid = {39126548}, issn = {1573-8221}, mesh = {*Bordetella pertussis/immunology/pathogenicity ; *Pertussis Vaccine/immunology ; Animals ; *Biofilms/drug effects/growth &amp; development ; *Whooping Cough/prevention &amp; control/microbiology/immunology ; Mice ; *Vaccines, Acellular/immunology ; Plankton/drug effects/immunology ; Antigens, Bacterial/immunology ; Female ; Mice, Inbred BALB C ; Administration, Intranasal ; }, abstract = {Continued circulation of the whooping cough pathogen, even in countries with high vaccine coverage, can be related to persistence of Bordetella pertussis biofilms in the respiratory tract. The films differ from planktonic cells by increased resistance to the host immune system and antibacterial drugs. The available acellular pertussis vaccines (aPV) containing antigens isolated from planktonic cultures of B. pertussis protect from severe forms of whooping cough, but do not effectively influence circulation of virulent strains in the subclinical forms of the disease and asymptomatic carriage. It is promising to create new generation aPV based on antigens isolated from biofilm cultures of B. pertussis capable of more effectively controlling the entire infectious cycle of whooping cough, including colonization, persistence, and transmission of the pathogen. From antigenic complexes isolated from the culture medium of biofilm and planktonic cultures of the strain B. pertussis No. 317 (serotype 1.2.3), experimental aPV were made: aPV-B and aPV-P, respectively. In intracerebral infection of mice with a virulent strain of B. pertussis, aPV-B demonstrated 2.5-fold higher protective activity than aPV-P and also more effectively reduced colonization of the lungs by B. pertussis cells in mice after intranasal infection with a virulent strain. Both vaccine preparations were safe and did not cause death in mice after administration of histamine.}, }
@article {pmid39126293, year = {2024}, author = {Gallas, JA and Pelozo, LL and Corona, SAM and Shen, Y and Haapasalo, M and Sousa-Neto, MD and Souza-Gabriel, AE}, title = {Effect of pomegranate solution alone or combined with chlorhexidine against oral multispecies biofilm.}, journal = {International endodontic journal}, volume = {57}, number = {12}, pages = {1819-1828}, doi = {10.1111/iej.14135}, pmid = {39126293}, issn = {1365-2591}, support = {//Coordena&#xe7;&#xe3;o de Aperfei&#xe7;oamento de Pessoal de N&#xed;vel Superior/ ; }, mesh = {*Biofilms/drug effects ; *Pomegranate/chemistry ; *Plant Extracts/pharmacology ; *Chlorhexidine/pharmacology ; Humans ; Anti-Infective Agents, Local/pharmacology ; Hydrolyzable Tannins/pharmacology ; Microscopy, Confocal ; Dental Plaque/microbiology ; }, abstract = {AIM: Natural bioactive products have been tested as alternative antimicrobial agents. This study evaluated the effect of Punica granatum extract (PGE) on oral multispecies biofilms.<br><br>METHODOLOGY: Lyophilized extracts from pomegranate peel were prepared, and the punicalagin content was assessed by ultra-performance liquid chromatography (UPLC). Oral multispecies biofilms from 2 donors were grown on four collagen-coated hydroxyapatite discs. After incubation for 7&#x2009;days or 3&#x2009;weeks, the biofilms were exposed to water (control), 2% CHX, 10% PGE, 20% PGE or 30% PGE for 3&#x2009;min. The proportions of dead bacteria were assessed by the live/dead staining and confocal microscopy. After the analysis, the best PGE concentration (30%) was combined with CHX. The experimental phases were repeated using water, 2% CHX, 30% PGE and 30% PGE&#x2009;+&#x2009;2% CHX. Five random areas of the biofilm on each disc were scanned, resulting in 20 scanned areas for each group.<br><br>RESULTS: Regarding the biofilm volume, no differences were found amongst solutions (p&#x2009;=&#x2009;.111). The PGE solution killed bacteria effectively in 1-week, 2-week and 3-week-old-plaque biofilms, ranging from 37 to 55.3%, depending on the PGE concentration. The 30% PGE (a) (p&#x2009;=&#x2009;.0009) had greater antibiofilm effectiveness than 2% CHX (b), which killed bacteria in the 25.2 to 48.7% range. The 10% and 20% PGE had intermediate values (ab), without significant differences from 30% PGE (p&#x2009;=&#x2009;1.002). Water (c) had the lowest proportion of dead bacteria (p&#x2009;<&#x2009;.00001) in a range of 5 to 6.7% and lower effectiveness in killing bacteria (p&#x2009;<&#x2009;.05). The PGE alone or mixed with 2% CHX had greater anti-biofilm effectiveness than CHX (p&#x2009;<&#x2009;.05). The old plaque biofilms were more resistant than the 7-day-old plaque (p&#x2009;<&#x2009;.05).<br><br>CONCLUSIONS: The 30% PGE (alone or combined with CHX) exhibited a greater antibiofilm effect on oral multispecies biofilms grown on hydroxyapatite discs than 2% CHX.}, }
@article {pmid39125921, year = {2024}, author = {Rajewska, M and Maciąg, T and Narajczyk, M and Jafra, S}, title = {Carbon Source and Substrate Surface Affect Biofilm Formation by the Plant-Associated Bacterium Pseudomonas donghuensis P482.}, journal = {International journal of molecular sciences}, volume = {25}, number = {15}, pages = {}, pmid = {39125921}, issn = {1422-0067}, support = {2015/19/D/NZ9/03588//National Science Center/ ; }, mesh = {*Biofilms/growth &amp; development ; *Pseudomonas/physiology/metabolism/genetics ; *Carbon/metabolism ; Plant Roots/microbiology ; Rhizosphere ; Solanum lycopersicum/microbiology ; Zea mays/microbiology ; Glass ; Bacterial Adhesion ; Glycerol/metabolism ; Polystyrenes ; }, abstract = {The ability of bacteria to colonize diverse environmental niches is often linked to their competence in biofilm formation. It depends on the individual characteristics of a strain, the nature of the colonized surface (abiotic or biotic), or the availability of certain nutrients. Pseudomonas donghuensis P482 efficiently colonizes the rhizosphere of various plant hosts, but a connection between plant tissue colonization and the biofilm formation ability of this strain has not yet been established. We demonstrate here that the potential of P482 to form biofilms on abiotic surfaces and the structural characteristics of the biofilm are influenced by the carbon source available to the bacterium, with glycerol promoting the process. Also, the type of substratum, polystyrene or glass, impacts the ability of P482 to attach to the surface. Moreover, P482 mutants in genes associated with motility or chemotaxis, the synthesis of polysaccharides, and encoding proteases or regulatory factors, which affect biofilm formation on glass, were fully capable of colonizing the root tissue of both tomato and maize hosts. Investigating the role of cellular factors in biofilm formation using these plant-associated bacteria shows that the ability of bacteria to form biofilm on abiotic surfaces does not necessarily mirror its ability to colonize plant tissues. Our research provides a broader perspective on the adaptation of these bacteria to various environments.}, }
@article {pmid39125609, year = {2024}, author = {Alfeqy, MM and El-Hawary, SS and El-Halawany, AM and Rabeh, MA and Alshehri, SA and Abdelmohsen, UR and Safwat, NA and Serry, AM and Fahmy, HA and Ezzat, MI}, title = {Biosynthesis and Characterization of Aeonium arboreum-Derived Silver Nanoparticles: Antimicrobial Activity, Biofilm Inhibition, Antihemolytic Activity, and In Silico Studies.}, journal = {International journal of molecular sciences}, volume = {25}, number = {15}, pages = {}, pmid = {39125609}, issn = {1422-0067}, support = {RGP1/192/45//Deanship of Scientific Research at King Khalid University/ ; }, mesh = {*Metal Nanoparticles/chemistry ; *Silver/chemistry/pharmacology ; *Biofilms/drug effects ; *Microbial Sensitivity Tests ; *Molecular Docking Simulation ; Plant Extracts/chemistry/pharmacology ; Anti-Infective Agents/pharmacology/chemistry ; Anti-Bacterial Agents/pharmacology/chemistry ; Candida albicans/drug effects ; Pseudomonas aeruginosa/drug effects ; Computer Simulation ; }, abstract = {Environmentally friendly biosynthesis of silver nanoparticles (AgNPs) from Aeonium arboreum (L.) Webb &amp; Berthel is reported for the first time. The synthesized AgNPs were characterized using UV-Vis, FTIR, TEM, Zeta potential, and XRD analysis, revealing high stability (-29.1 mV), spherical shape, and an average size of 100 nm. The antimicrobial activity levels of both A. arboreum extract and biosynthesized AgNPs were evaluated against five uropathogens (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans). Both the extract and the AgNPs exhibited significant efficacy, particularly against E. coli, with inhibition zones of 27 mm and 30 mm, respectively. LC-MS analysis tentatively identified 11 secondary metabolites in the extract, including quercetin-3-O-glucoside, quercetin-3-O-rhamnoside, myricetin 3-glucoside, and daphneresinol. In silico docking studies revealed promising binding affinities of these metabolites in relation to key enzymes involved in bacterial folate synthesis (dihydrofolate reductase (DHFR) and dihydropteroate synthase (DHPS)) and DNA replication (DNA gyrase). These findings demonstrate the potential of A. arboreum-based AgNPs and their associated metabolites as a novel therapeutic approach for combating urinary tract infections. Their antimicrobial, antihemolytic, and antibiofilm properties warrant further investigation.}, }
@article {pmid39125195, year = {2024}, author = {Guckeisen, T and Orghici, R and Rathgeber, S}, title = {Correlative Effects on Nanoplastic Aggregation in Model Extracellular Biofilm Substances Investigated with Fluorescence Correlation Spectroscopy.}, journal = {Polymers}, volume = {16}, number = {15}, pages = {}, pmid = {39125195}, issn = {2073-4360}, abstract = {Recent studies show that biofilm substances in contact with nanoplastics play an important role in the aggregation and sedimentation of nanoplastics. Consequences of these processes are changes in biofilm formation and stability and changes in the transport and fate of pollutants in the environment. Having a deeper understanding of the nanoplastics-biofilm interaction would help to evaluate the risks posed by uncontrolled nanoplastic pollution. These interactions are impacted by environmental changes due to climate change, such as, e.g., the acidification of surface waters. We apply fluorescence correlation spectroscopy (FCS) to investigate the pH-dependent aggregation tendency of non-functionalized polystyrene (PS) nanoparticles (NPs) due to intermolecular forces with model extracellular biofilm substances. Our biofilm model consists of bovine serum albumin (BSA), which serves as a representative for globular proteins, and the polysaccharide alginate, which is a main component in many biofilms, in solutions containing Na[+] with an ionic strength being realistic for fresh-water conditions. Biomolecule concentrations ranging from 0.5 g/L up to at maximum 21 g/L are considered. We use non-functionalized PS NPs as representative for mostly negatively charged nanoplastics. BSA promotes NP aggregation through adsorption onto the NPs and BSA-mediated bridging. In BSA-alginate mixtures, the alginate hampers this interaction, most likely due to alginate-BSA complex formation. In most BSA-alginate mixtures as in alginate alone, NP aggregation is predominantly driven by weaker, pH-independent depletion forces. The stabilizing effect of alginate is only weakened at high BSA contents, when the electrostatic BSA-BSA attraction is not sufficiently screened by the alginate. This study clearly shows that it is crucial to consider correlative effects between multiple biofilm components to better understand the NP aggregation in the presence of complex biofilm substances. Single-component biofilm model systems based on comparing the total organic carbon (TOC) content of the extracellular biofilm substances, as usually considered, would have led to a misjudgment of the stability towards aggregation.}, }
@article {pmid39123725, year = {2024}, author = {Hai, H and Yang, M and Cheng, Z and Ma, K and Shang, F}, title = {Potential Role of SdiA in Biofilm Formation and Drug Resistance in Avian Pathogenic Escherichia coli.}, journal = {Animals : an open access journal from MDPI}, volume = {14}, number = {15}, pages = {}, pmid = {39123725}, issn = {2076-2615}, abstract = {Avian pathogenic Escherichia coli (APEC) constitutes a significant cause of colibacillosis, a localized or systemic inflammatory disorder in avian species, resulting in considerable economic losses within the global poultry industry. SdiA (suppressor of division inhibitor) is a transcription factor recognized as a LuxR homolog in Escherichia coli, regulating various behaviors, including biofilm formation, multidrug resistance, and the secretion of virulence factors. However, the function of SdiA in APEC strains and its correlation with virulence and multidrug resistance remains unknown. This study probed into the function of SdiA by analyzing the effect of sdiA deletion on the transcription profile of an APEC strain. The microarray data revealed that SdiA upregulates 160 genes and downregulates 59 genes, exerting a particularly remarkable influence on the transcription of multiple virulence genes. A series of antibiotic sensitivity tests, biofilm formation assays, motility assays, and transcriptome analyses were performed, while a Normality test and t-test were conducted on the datasets. This research confirmed that SdiA inhibits biofilm formation by 1.9-fold (p-value < 0.01) and motility by 1.5-fold (p-value < 0.01). RT-qPCR revealed that SdiA positively regulates multidrug resistance by upregulating the expression of yafP, cbrA, and eamB. Collectively, the results of this study indicate the role of SdiA in the pathogenesis of APEC by controlling biofilm formation, motility, and multidrug resistance.}, }
@article {pmid39122151, year = {2024}, author = {Demontier, E and Ster, C and Chamberland, S and Ramanathan, S and Dufour, S and Malouin, F}, title = {Biofilm Dairy Foods Review: Effect of biofilm production on antimicrobial susceptibility of Staphylococcus aureus bovine mastitis strains from the most prevalent Canadian spa types.}, journal = {Journal of dairy science}, volume = {}, number = {}, pages = {}, doi = {10.3168/jds.2024-25238}, pmid = {39122151}, issn = {1525-3198}, abstract = {Staphylococcus aureus intramammary infections often leads to clinical and subclinical mastitis in dairy cattle. Prediction of disease evolution and treatment efficacy based on the characteristics of disease-causing strains of S. aureus would significantly improve management of dairy herds. To study the impact of biofilm production and the influence of genetic lineage, we selected S. aureus isolates from the most prevalent Canadian spa types associated with bovine mastitis. Antimicrobial susceptibility in planktonic growth and for bacteria embedded in biofilm was compared. PCR was used to detect the bap gene responsible for atypical biofilm formation. All Canadian spa types from dairy cattle were susceptible to the 8 antimicrobial agents tested. Only strain sa3493 from spa type t267 showed a resistance to pirlimycin. However, bacteria producing larger amounts of biofilms better survived the bactericidal action of antimicrobial agents even when exposed to concentrations 64 folds higher than the minimal inhibitory concentration determined for planktonic cultures. Pirlimycin was more effective on bacteria producing low to moderate levels of biofilm compared with vancomycin or ceftiofur. Antimicrobial agents did not affect the viability of spa types t13401 and t605 that were high biofilm producers. While both these spa types produced high amounts of biofilm, only t605 possessed the bap gene. We also found a close relationship between DIM at sampling and the presence of spa type t605 isolates. These results suggest that detection of S. aureus spa type may help predict the effectiveness of antimicrobial therapy and that some spa types are more likely to be retrieved toward the end of the lactation.}, }
@article {pmid39122126, year = {2024}, author = {Wang, XT and Zhao, L and Zhang, Q and Wang, B and Xing, D and Nan, J and Ren, NQ and Lee, DJ and Chen, C}, title = {Linking performance to dynamic migration of biofilm ecosystem reveals the role of voltage in the start-up of hybrid microbial electrolysis cell-anaerobic digestion.}, journal = {Bioresource technology}, volume = {411}, number = {}, pages = {131242}, doi = {10.1016/j.biortech.2024.131242}, pmid = {39122126}, issn = {1873-2976}, mesh = {*Biofilms ; *Electrolysis ; *Methane/metabolism ; *Electrodes ; Anaerobiosis/physiology ; *Bioelectric Energy Sources/microbiology ; Sewage/microbiology ; Electricity ; Ecosystem ; Bioreactors/microbiology ; Biomass ; }, abstract = {Applied voltage is a crucial parameter in hybrid microbial electrolysis cells-anaerobic digestion (MEC-AD) systems for enhancing methane production from waste activated sludge (WAS). This study explored the impact of applied voltage on the initial biofilm formation on electrodes during the MEC-AD startup using raw WAS (Rr) and heat-pretreated WAS (Rh). The findings indicated that the maximum methane productivity for Rr and Rh were 3.4 ± 0.5 and 3.4 ± 0.2 mL/gVSS/d, respectively, increasing 1.5 times and 2.6 times over the productivity at 0 V. The biomass on electrode biofilms for Rr and Rh at 0.8 V increased by 70 % and 100 % compared to 0 V. The core functional microorganisms in the cathode biofilm were Methanobacterium and Syntrophomonas, and Geobacter in the anode biofilm, enhancing methane production through syntrophism and direct interspecies electron transfer, respectively. These results offer academic insights into optimizing AD functional electrode biofilms by applying voltage.}, }
@article {pmid39121346, year = {2024}, author = {Barta, A and Salusso, A and Kúsz, N and Berkecz, R and Schlauer, J and Purger, D and Hohmann, J and Carpinella, MC and Vasas, A}, title = {Phenanthrenes from Juncus articulatus with Antibacterial and Biofilm Formation Inhibitory Activity.}, journal = {Journal of natural products}, volume = {87}, number = {8}, pages = {2068-2080}, pmid = {39121346}, issn = {1520-6025}, mesh = {*Anti-Bacterial Agents/pharmacology/chemistry ; *Biofilms/drug effects ; *Phenanthrenes/pharmacology/chemistry/isolation &amp; purification ; *Microbial Sensitivity Tests ; Molecular Structure ; *Methicillin-Resistant Staphylococcus aureus/drug effects ; Escherichia coli/drug effects ; Pseudomonas aeruginosa/drug effects ; Staphylococcus aureus/drug effects ; }, abstract = {Continuing our search for bioactive compounds in species from the Juncaceae family, Juncus articulatus was investigated. Ten previously undescribed phenanthrenes─articulins A-J (1-10)─and ten known compounds─juncuenin B, dehydrojuncuenin B, juncatrin B, ensifolins E, F, H, I, K, juncuenin D, and luzulin A (11-20)─along with other compounds, have been isolated and identified. The isolated compounds were evaluated for antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, methicillin-susceptible Staphylococcus aureus (MSSA), and methicillin-resistant Staphylococcus aureus (MRSA). Compounds 12 and 14 exhibited the most potent activity against planktonic and sessile MSSA and MRSA with minimum inhibitory concentration (MIC) values of 15.1 μM (12 for both bacterial strains) and 15.3 μM (14 for both bacterial strains). Compounds 15, 17, and 18 also exhibited activity against both strains, although to a lower extent, with MIC values ranging from 30.0 to 56.8 μM. The inhibition of biofilm formation of these compounds was observed at 15.1-114.3 μM. This study elucidates the phenanthrene composition of J. articulatus and the antibacterial effect of these compounds.}, }
@article {pmid39119620, year = {2024}, author = {Astrada, A and Nakagami, G and Sanada, H}, title = {Challenges in Biofilm Identification in Diabetic Foot Infections: Review of Literature.}, journal = {The international journal of lower extremity wounds}, volume = {}, number = {}, pages = {15347346241273112}, doi = {10.1177/15347346241273112}, pmid = {39119620}, issn = {1552-6941}, abstract = {Foot ulcerations are one of the most common complications of diabetes and one of the major initial causes of amputations. The formation of biofilms on wounds significantly contributes to infections and delayed healing. While existing methods for identifying these biofilms have limitations, there is a need for a convenient tool for its clinical application. This literature review aimed to address the problem with current clinical biofilm identification in wound care and a proposal for biofilm-detection-based wound care in diabetic foot ulcer patients. Identifying biofilms is particularly vital due to the absence of typical signs of infection in DFUs. However, current approaches, although effective, often prove invasive and technically intricate. The wound blotting technique, involving attaching a nitrocellulose membrane and subsequent staining, presents an alternative that is swift and non-invasive. Research highlights the applicability of wound blotting with alcian blue staining in clinical scenarios, consistently producing sensitive outcomes. By addressing the critical need for early biofilm detection, wound blotting holds promise for enhancing DFU management and contributing to strategies aimed at preventing amputations.}, }
@article {pmid39116779, year = {2024}, author = {Guo, M and Tan, S and Wu, Y and Zheng, C and Du, P and Zhu, J and Sun, A and Liu, X}, title = {BrfA functions as a bacterial enhancer-binding protein to regulate functional amyloid Fap-dependent biofilm formation in Pseudomonas fluorescens by sensing cyclic diguanosine monophosphate.}, journal = {Microbiological research}, volume = {287}, number = {}, pages = {127864}, doi = {10.1016/j.micres.2024.127864}, pmid = {39116779}, issn = {1618-0623}, mesh = {*Biofilms/growth &amp; development ; *Pseudomonas fluorescens/genetics/metabolism/physiology ; *Gene Expression Regulation, Bacterial ; *Bacterial Proteins/genetics/metabolism ; *Cyclic GMP/analogs &amp; derivatives/metabolism ; Amyloid/metabolism ; Promoter Regions, Genetic ; Protein Binding ; Sigma Factor/genetics/metabolism ; }, abstract = {The functional amyloid of Pseudomonas (Fap) is essential for the formation of macrocolony biofilms, pellicles, and solid surface-associated (SSA) biofilms of Pseudomonas fluorescens PF07, an isolate from refrigerated marine fish. However, limited information on the expression regulation of fap genes is available. Herein, we found that a novel bacterial enhancer-binding protein (bEBP), BrfA, regulated Fap-dependent biofilm formation by directly sensing cyclic diguanosine monophosphate (c-di-GMP). Our in vivo data showed that the REC domain deletion of BrfA promoted fap gene expression and biofilm formation, and c-di-GMP positively regulated the transcription of fapA in a BrfA-dependent manner. In in vitro experiments, we found that the ATPase activity of BrfA was inhibited by the REC domain and was activated by c-di-GMP. BrfA and the sigma factor RpoN bound to the upstream region of fapA, and the binding ability of BrfA was not affected by either deletion of the REC domain or c-di-GMP. BrfA specifically bound to the three enhancer sites upstream of the fapA promoter, which contain the consensus sequence CA-(N4)-TGA(A/T)ACACC. In vivo experiments using a lacZ fusion reporter indicated that all three BrfA enhancer sites were essential for the activation of fapA transcription. Overall, these findings reveal that BrfA is a new type of c-di-GMP-responsive transcription factor that directly controls the transcription of Fap biosynthesis genes in P. fluorescens. Fap functional amyloids and BrfA-type transcription factors are widespread in Pseudomonas species. The novel insights into the c-di-GMP- and BrfA-dependent expression regulation of fap provided by this work will contribute to the development of antibiofilm strategies.}, }
@article {pmid39116134, year = {2024}, author = {Hansen, KH and Byeon, CH and Liu, Q and Drace, T and Boesen, T and Conway, JF and Andreasen, M and Akbey, &#xdc;}, title = {Structure of biofilm-forming functional amyloid PSMα1 from Staphylococcus aureus.}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, volume = {121}, number = {33}, pages = {e2406775121}, pmid = {39116134}, issn = {1091-6490}, mesh = {*Staphylococcus aureus/metabolism/physiology ; *Biofilms/growth &amp; development ; *Amyloid/metabolism/chemistry ; Bacterial Toxins/metabolism/chemistry ; Protein Conformation ; Bacterial Proteins/metabolism/chemistry ; Models, Molecular ; }, abstract = {Biofilm-protected pathogenic Staphylococcus aureus causes chronic infections that are difficult to treat. An essential building block of these biofilms are functional amyloid fibrils that assemble from phenol-soluble modulins (PSMs). PSMα1 cross-seeds other PSMs into cross-β amyloid folds and is therefore a key element in initiating biofilm formation. However, the paucity of high-resolution structures hinders efforts to prevent amyloid assembly and biofilm formation. Here, we present a 3.5 Å resolution density map of the major PSMα1 fibril form revealing a left-handed cross-β fibril composed of two C2-symmetric U-shaped protofilaments whose subunits are unusually tilted out-of-plane. Monomeric α-helical PSMα1 is extremely cytotoxic to cells, despite the moderate toxicity of the cross-β fibril. We suggest mechanistic insights into the PSM functional amyloid formation and conformation transformation on the path from monomer-to-fibril formation. Details of PSMα1 assembly and fibril polymorphism suggest how S. aureus utilizes functional amyloids to form biofilms and establish a framework for developing therapeutics against infection and antimicrobial resistance.}, }
@article {pmid39115732, year = {2024}, author = {Abdul Raheem, N and Selvaraj, GK and Karuppanan, K and Ganesan, G and Soorangkattan, S and Subramanian, B and Ramamurthy Baluraj, S and Rajaiah, DK and Hasan, I}, title = {Bioremediation of heavy metals by an unexplored bacterium, Pseudoxanthomonas mexicana strain GTZY isolated from aerobic-biofilm wastewater system.}, journal = {Environmental science and pollution research international}, volume = {}, number = {}, pages = {}, pmid = {39115732}, issn = {1614-7499}, abstract = {We prompted to characterize a wastewater bacterium, Pseudoxanthomonas mexicana GTZY, that efficiently transforms toxic mercury and arsenic, explores its bioremediation capability, and reveals their relevant gene resistance operons. The isolated strain was characterized by its phylogenetic, biochemical, and phenotypic properties. The strain GTZY potentially removed 84.3% of mercury and their mercury volatilization (Hg(II) to Hg(0)) was confirmed using the X-ray film method, and its respective merA gene was PCR amplified. In addition, strain GTZY efficiently removed arsenate (68.5%) and arsenite (63.2%), and showed resistance up to > 175 and > 55 mM, respectively. Their genomic annotations disclosed the linkage of Tn2-transposon and int1 in both ends of mer operon (merAPTR). The co-existence of arsP and arsH proteins in its intrinsic ars operon (arsCPRH) was extremely diverse from its ancestral species. We believe that the mercury resistance-conferring mer operon of P. mexicana GTZY presumably derived horizontally from other species in the reactor, while the arsenic resistance-conferring intrinsic ars operon was highly diversified and evolved from its ancestral species. By considering the potential of the strain GTZY to transform heavy metals, this can be used to recover contaminated sites.}, }
@article {pmid39113613, year = {2024}, author = {Chen, M and Trotter, VV and Walian, PJ and Chen, Y and Lopez, R and Lui, LM and Nielsen, TN and Malana, RG and Thorgersen, MP and Hendrickson, AJ and Carion, H and Deutschbauer, AM and Petzold, CJ and Smith, HJ and Arkin, AP and Adams, MWW and Fields, MW and Chakraborty, R}, title = {Molecular mechanisms and environmental adaptations of flagellar loss and biofilm growth of Rhodanobacter under environmental stress.}, journal = {The ISME journal}, volume = {18}, number = {1}, pages = {}, pmid = {39113613}, issn = {1751-7370}, support = {//ENIGMA-Ecosystems and Networks Integrated with Genes and Molecular Assemblies/ ; DE-AC02-05CH11231//US Department of Energy, Office of Science, Office of Biological and Environmental Research/ ; }, mesh = {*Biofilms/growth &amp; development ; *Flagella/genetics/physiology ; *Stress, Physiological ; *Aluminum/toxicity ; *Adaptation, Physiological ; Hydrogen-Ion Concentration ; Nitrates/metabolism ; Groundwater/microbiology ; Bacterial Proteins/genetics/metabolism ; }, abstract = {Biofilms aid bacterial adhesion to surfaces via direct and indirect mechanisms, and formation of biofilms is considered as an important strategy for adaptation and survival in suboptimal environmental conditions. However, the molecular underpinnings of biofilm formation in subsurface sediment/groundwater ecosystems where microorganisms often experience fluctuations in nutrient input, pH, and nitrate or metal concentrations are underexplored. We examined biofilm formation under different nutrient, pH, metal, and nitrate regimens of 16 Rhodanobacter strains isolated from subsurface groundwater wells spanning diverse levels of pH (3.5 to 5) and nitrates (13.7 to 146 mM). Eight Rhodanobacter strains demonstrated significant biofilm growth under low pH, suggesting adaptations for survival and growth at low pH. Biofilms were intensified under aluminum stress, particularly in strains possessing fewer genetic traits associated with biofilm formation, findings warranting further investigation. Through random barcode transposon-site sequencing (RB-TnSeq), proteomics, use of specific mutants, and transmission electron microscopy analysis, we discovered flagellar loss under aluminum stress, indicating a potential relationship between motility, metal tolerance, and biofilm growth. Comparative genomic analyses revealed the absence of flagella and chemotaxis genes and the presence of a putative type VI secretion system in the highly biofilm-forming strain FW021-MT20. In this study we identified genetic determinants associated with biofilm growth under metal stress in a predominant environmental genus, Rhodanobacter, and identified traits aiding survival and adaptation to contaminated subsurface environments.}, }
@article {pmid39112554, year = {2025}, author = {Rumbaugh, KP and Whiteley, M}, title = {Towards improved biofilm models.}, journal = {Nature reviews. Microbiology}, volume = {23}, number = {1}, pages = {57-66}, pmid = {39112554}, issn = {1740-1534}, mesh = {*Biofilms/growth &amp; development ; *Models, Biological ; Humans ; Bacterial Physiological Phenomena ; }, abstract = {Biofilms are complex microbial communities that have a critical function in many natural ecosystems, industrial settings as well as in recurrent and chronic infections. Biofilms are highly heterogeneous and dynamic assemblages that display complex responses to varying environmental factors, and those properties present substantial challenges for their study and control. In recent years, there has been a growing interest in developing improved biofilm models to offer more precise and comprehensive representations of these intricate systems. However, an objective assessment for ascertaining the ability of biofilms in model systems to recapitulate those in natural environments has been lacking. In this Perspective, we focus on medical biofilms to delve into the current state-of-the-art in biofilm modelling, emphasizing the advantages and limitations of different approaches and addressing the key challenges and opportunities for future research. We outline a framework for quantitatively assessing model accuracy. Ultimately, this Perspective aims to provide a comprehensive and critical overview of medically focused biofilm models, with the intent of inspiring future research aimed at enhancing the biological relevance of biofilm models.}, }
@article {pmid39111496, year = {2024}, author = {Lin, N and Wang, M and Gong, H and Li, N and Liu, F and Wu, Y and Sun, X and Yang, Q and Tan, X}, title = {Immobilizing DNase in ternary AuAgCu hydrogels to accelerate biofilm disruption for synergistically enhanced therapy of MRSA infections.}, journal = {International journal of biological macromolecules}, volume = {277}, number = {Pt 4}, pages = {134518}, doi = {10.1016/j.ijbiomac.2024.134518}, pmid = {39111496}, issn = {1879-0003}, mesh = {*Biofilms/drug effects ; *Hydrogels/chemistry/pharmacology ; *Methicillin-Resistant Staphylococcus aureus/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Deoxyribonucleases/chemistry/pharmacology/metabolism ; *Gold/chemistry/pharmacology ; *Staphylococcal Infections/drug therapy ; Animals ; Copper/chemistry/pharmacology ; Microbial Sensitivity Tests ; Mice ; Enzymes, Immobilized/chemistry/pharmacology ; Wound Healing/drug effects ; }, abstract = {Bacterial biofilm-related infections have become a significant global concern in public health and economy. Extracellular DNA (eDNA) is regarded as one of the key elements of extracellular polymeric substances (EPS) in bacterial biofilm, providing robust support to maintain the stability of bacterial biofilms for fighting against environmental stresses (such as antibiotics, reactive oxygen species (ROS), and hyperthermia). In this study, ternary AuAgCu hydrogels nanozyme with porous network structures were utilized for the immobilization of DNase (AuAgCu@DNase hydrogels) to realize enhanced biofilm decomposition and antibacterial therapy of MRSA. The prepared AuAgCu@DNase hydrogels can efficiently hydrolyze eDNA in biofilms so that the generated ROS and hyperthermia by laser irradiation can permeate into the interior of the biofilm to achieve deep sterilization. The typical interface interactions between AuAgCu hydrogels and DNase and the excellent photothermal-boost peroxidase-like performances of AuAgCu hydrogels take responsibility for the enhanced antibacterial activity. In the MRSA-infected wounds model, the in vivo antibacterial results revealed that the AuAgCu@DNase hydrogels possess excellent drug-resistant bacteria-killing performance with superb biocompatibility. Meanwhile, the pathological analysis of collagen deposition and fibroblast proliferation of wounds demonstrate highly satisfactory wound healing. This work offers an innovative path for developing nanozyme-enzyme antibacterial composites against drug-resistant bacteria and their biofilms.}, }
@article {pmid39111435, year = {2024}, author = {Liao, R and Song, Z and Zhang, X and Xiong, X and Zhang, Z and Zhao, Z and Sun, F}, title = {Versatile enhancement for anaerobic moving bed biofilm (AnMBBR) treating pretreated landfill leachate by hydrochar: Energy recovery, greenhouse gas emission reduction and underlying microbial mechanisms.}, journal = {The Science of the total environment}, volume = {951}, number = {}, pages = {175161}, doi = {10.1016/j.scitotenv.2024.175161}, pmid = {39111435}, issn = {1879-1026}, mesh = {*Biofilms ; Anaerobiosis ; *Water Pollutants, Chemical/analysis ; *Bioreactors ; *Waste Disposal, Fluid/methods ; *Greenhouse Gases/analysis ; Methane/metabolism ; Biological Oxygen Demand Analysis ; }, abstract = {Hydrochars were prepared from fruit peels (HC-1) and vegetable waste (HC-2), and combined with fiber spheres, respectively, to form homogeneous biocompatible carriers, which were used for anaerobic moving bed biofilm reactor (AnMBBR) to enhance anaerobic digestion (AD) performance and energy recovery of landfill leachate treatment. Compared with the control AnMBBR with conventional fiber spheres as carriers, the chemical oxygen demand (COD) removal efficiency of the AnMBBR with HC-2 increased from 75 % to 88 %, methane yield increased from 77.7 mL/g-COD to 155.3 mL/g-COD, and achieved greenhouse gases (GHG) emission reductions of 1.74 t CO2 eq/a during long-term operation. HC-2-fiber sphere biocarriers provided more sites for attached-growth biomass (AGBS) and significantly enhanced the abundance of functional microbial community, with the relative abundance of methanogenic bacteria Methanothrix increased from 0.03 % to over 24.4 %. Moreover, the gene abundance of most the key enzymes encoding the hydrolysis, acidogenesis and methanogenesis pathways were up-regulated with the assistance of HC-2. Consequently, hydrochar-assisted AnMBBR were effective to enhance methanogenesis performance, energy recovery and carbon reduction for high-strength landfill leachate treatment.}, }
@article {pmid39111368, year = {2024}, author = {Ahmed, F and Mirani, ZA and Urooj, S and Noor Ul Hudda, H and Janees Imdad, M and Zhao, Y and Malakar, PK}, title = {A rare biofilm dispersion strategy demonstrated by Staphylococcus aureus under oxacillin stress.}, journal = {Microbial pathogenesis}, volume = {194}, number = {}, pages = {106838}, doi = {10.1016/j.micpath.2024.106838}, pmid = {39111368}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Oxacillin/pharmacology ; *Anti-Bacterial Agents/pharmacology ; *Methicillin-Resistant Staphylococcus aureus/drug effects/genetics/physiology ; *Microbial Sensitivity Tests ; Bacterial Proteins/genetics/metabolism ; Staphylococcal Infections/microbiology ; Microscopy, Electron, Scanning ; Humans ; Staphylococcus aureus/drug effects/genetics/physiology ; }, abstract = {Staphylococcus aureus (S. aureus), a versatile Gram-positive bacterium, is implicated in a spectrum of infections, and its resilience is often attributed to biofilm formation. This study investigates the effect of sub-inhibitory doses of oxacillin on biofilm formation by methicillin-resistant S. aureus (MRSA). Specifically, it examines how these doses influence biofilms' development, maturation, and dispersal. The biofilm's zenith reached 48 h of incubation, followed by a noteworthy decline at 96 h and a distinctive clearance zone around biofilm-positive cells exposed to oxacillin. Scanning electron micrographs unveiled an intriguing active biofilm dispersal mechanism, a rarity in this species. Among 180 isolates, only three carrying the elusive icaD gene exhibited this phenomenon. icaD gene was absent in their counterparts. Notably, the icaD gene emerges as a distinctive marker, crucial in regulating biofilm dispersion and setting these isolates apart. The captivating interplay of oxacillin, biofilm dynamics, and genetic signatures disintegrate novel dimensions in understanding MRSA's adaptive strategies and underscores the importance of the icaD gene in engineering biofilm resilience.}, }
@article {pmid39110759, year = {2024}, author = {Vieira, B and Alcantara, JB and Destro, G and Guerra, MES and Oliveira, S and Lima, CA and Longato, GB and Hakansson, AP and Leite, LC and Darrieux, M and R Converso, T}, title = {Role of the polyamine transporter PotABCD during biofilm formation by Streptococcus pneumoniae.}, journal = {PloS one}, volume = {19}, number = {8}, pages = {e0307573}, pmid = {39110759}, issn = {1932-6203}, mesh = {*Biofilms/growth &amp; development ; *Streptococcus pneumoniae/physiology/metabolism ; Animals ; Mice ; Polyamines/metabolism ; Bacterial Proteins/metabolism/genetics ; Pneumococcal Infections/microbiology ; Membrane Transport Proteins/metabolism/genetics ; Operon ; }, abstract = {Streptococcus pneumoniae is a bacterium of great global importance, responsible for more than one million deaths per year. This bacterium is commonly acquired in the first years of life and colonizes the upper respiratory tract asymptomatically by forming biofilms that persist for extended times in the nasopharynx. However, under conditions that alter the bacterial environment, such as viral infections, pneumococci can escape from the biofilm and invade other niches, causing local and systemic disease of varying severity. The polyamine transporter PotABCD is required for optimal survival of the organism in the host. Immunization of mice with recombinant PotD can reduce subsequent bacterial colonization. PotD has also been suggested to be involved in pneumococcal biofilm development. Therefore, in this study we aimed to elucidate the role of PotABCD and polyamines in pneumococcal biofilm formation. First, the formation of biofilms was evaluated in the presence of exogenous polyamines-the substrate transported by PotABCD-added to culture medium. Next, a potABCD-negative strain was used to determine biofilm formation in different model systems using diverse levels of complexity from abiotic surface to cell substrate to in vivo animal models and was compared with its wild-type strain. The results showed that adding more polyamines to the medium stimulated biofilm formation, suggesting a direct correlation between polyamines and biofilm formation. Also, deletion of potABCD operon impaired biofilm formation in all models tested. Interestingly, more differences between wild-type and mutant strains were observed in the more complex model, which emphasizes the significance of employing more physiological models in studying biofilm formation.}, }
@article {pmid39108901, year = {2024}, author = {Haque, MM and Rupok, MRB and Molla, MAH and Rahman, MM and Shozib, HB and Mosharaf, MK}, title = {Rhizoengineering with biofilm producing rhizobacteria ameliorates oxidative stress and enhances bioactive compounds in tomato under nitrogen-deficient field conditions.}, journal = {Heliyon}, volume = {10}, number = {14}, pages = {e34276}, pmid = {39108901}, issn = {2405-8440}, abstract = {Nitrogen (N) deficiency limits crop productivity. In this study, rhizoengineering with biofilm producing rhizobacteria (BPR) contributing to productivity, physiology, and bioactive contents in tomato was examined under N-deficient field conditions. Here, different BPR including Leclercia adecarboxylata ESK12, Enterobacter ludwigii ESK17, Glutamicibacter arilaitensis ESM4, E. cloacae ESM12, Bacillus subtilis ESM14, Pseudomonas putida ESM17 and Exiguobacterium acetylicum ESM24 were used for the rhizoengineering of tomato plants. Rhizoengineered plants showed significant increase in growth attributes (15.73%-150.13 %) compared to the control plants. However, production of hydrogen peroxide (21.49-59.38 %), electrolyte leakage (19.5-38.07 %) and malondialdehyde accumulation (36.27-46.31 %) were increased remarkably more in the control plants than the rhizoengineered plants, thus N deficiency induced the oxidative stress. Compared to the control, photosynthetic rate, leaf temperature, stomatal conductance, intrinsic and instantaneous water use efficiency, relative water content, proline and catalase activity were incredibly enhanced in the rhizoengineered plants, suggesting both non-enzymatic and enzymatic antioxidant systems might protect tomato plants from oxidative stress under N-deficient field conditions. Yield (10.24-66.21 %), lycopene (4.8-7.94 times), flavonoids (52.32-110.46 %), phenolics (9.79-23.5 %), antioxidant activity (34.09-86.36 %) and certain minerals were significantly increased in the tomatoes from rhizoengineered plants. The principal component analysis (PCA) revealed that tomato plants treated with BPR induced distinct profiles compared to the control. Among all the applied BPR strains, ESM4 and ESM14 performed better in terms of biomass production, while ESK12 and ESK17 showed better results for reducing oxidative stress and increasing bioactive compounds in tomato, respectively. Thus, rhizoengineering with BPR can be utilized to mitigate the oxidative damage and increase the productivity and bioactive compounds in tomato under N-deficient field conditions.}, }
@article {pmid39108883, year = {2024}, author = {Swedan, SF and Aldakhily, DB}, title = {Antimicrobial resistance, biofilm formation, and molecular detection of efflux pump and biofilm genes among Klebsiella pneumoniae clinical isolates from Northern Jordan.}, journal = {Heliyon}, volume = {10}, number = {14}, pages = {e34370}, pmid = {39108883}, issn = {2405-8440}, abstract = {The current study aimed to investigate the antimicrobial susceptibility profiles, biofilm production capabilities, and the prevalence of efflux pump and biofilm-associated genes among Klebsiella pneumoniae clinical isolates. One hundred sixty-seven K. pneumoniae isolates were collected from microbiology laboratories in Northern Jordan hospitals. Antimicrobial susceptibility was tested using the Kirby-Bauer method. The double-disk synergy test was used to detect the extended-spectrum beta-lactamase (ESBL) phenotype. PCR was used to detect the frequency of acrAB, tolC, and mdtk efflux pump genes and fimH-1, mrkA, and mrkD biofilm-associated genes among the isolates. The highest nonsusceptibility was observed against azithromycin (87.4 %) and nitrofurantoin (85.0 %). Among the isolates, 75.4 % and 92.2 % were multidrug resistant and produced biofilms, respectively. Efflux pump genes acrAB, tolC, and mdtK were found in 96.4 %, 95.2 %, and 90.4 % of the isolates, respectively. Biofilm-associated genes mrkD, mrkA, and fimH-1 were found in 92.2 %, 89.2 %, and 88.6 % of the isolates, respectively. The presence of the mrkA was significantly associated with biofilm formation. Overall, high percentages of multi-drug resistance, efflux pump, and biofilm-associated genes were observed among the isolates. Subsequent studies are recommended to monitor changes in the prevalence of resistance phenotypes and genotypes of isolates.}, }
@article {pmid39107803, year = {2024}, author = {Dame-Teixeira, N and El-Gendy, R and de Oliveira, AS and Holanda, CA and Romeiro, LAS and Do, T}, title = {Engineering a dysbiotic biofilm model for testing root caries interventions through microbial modulation.}, journal = {Microbiome}, volume = {12}, number = {1}, pages = {145}, pmid = {39107803}, issn = {2049-2618}, support = {NIF\ R5\242/AMS_/Academy of Medical Sciences/United Kingdom ; NIF\ R5\242/AMS_/Academy of Medical Sciences/United Kingdom ; NIF\ R5\242/AMS_/Academy of Medical Sciences/United Kingdom ; }, mesh = {*Biofilms ; Humans ; *Root Caries/microbiology ; *Saliva/microbiology ; Cattle ; Animals ; *Microbiota ; Bacteria/genetics/isolation &amp; purification ; Dentin/microbiology ; Collagenases/metabolism ; }, abstract = {BACKGROUND: This study aimed to engineer and optimise a dysbiotic biofilm model to develop in vitro root caries for investigating microbial modulation strategies. The model involved growing complex biofilms from a saliva inoculum collected from four volunteers using two strategies. In the first strategy ("pre-treatment strategy"), bovine root slabs were used, and two natural compounds were incorporated at time 0 of the 10-day biofilm experiment, which included sucrose cycles mimicking the cariogenic environment. In the second strategy ("post-treatment strategy"), mature biofilms were grown in a modified Calgary biofilm device coated with collagen and hydroxyapatite for 7 days and then were exposed to the same natural compounds. The metatranscriptome of each biofilm was then determined and analysed. Collagenase activity was examined, and the biofilms and dentine were imaged using confocal and scanning electron microscopy (SEM). Mineral loss and lesion formation were confirmed through micro-computed tomography (μ-CT).<br><br>RESULTS: The pH confirmed the cariogenic condition. In the metatranscriptome, we achieved a biofilm compositional complexity, showing a great diversity of the metabolically active microbiome in both pre- and post-treatment strategies, including reads mapped to microorganisms other than bacteria, such as archaea and viruses. Carbohydrate esterases had increased expression in the post-treated biofilms and in samples without sugar cycles, while glucosyltransferases were highly expressed in the presence of sucrose cycles. Enrichment for functions related to nitrogen compound metabolism and organic cyclic component metabolism in groups without sucrose compared to the sucrose-treated group. Pre-treatment of the roots with cranberry reduced microbial viability and gelatinase (but not collagenase) activity (p&#x2009;<&#x2009;0.05). SEM images showed the complexity of biofilms was maintained, with a thick extracellular polysaccharides layer.<br><br>CONCLUSIONS: This root caries model was optimized to produce complex cariogenic biofilms and root caries-like lesions, and could be used to test microbial modulation in vitro. Pre-treatments before biofilm development and cariogenic challenges were more effective than post-treatments. The clinical significance lies in the potential to apply the findings to develop varnish products for post-professional tooth prophylaxis, aiming at implementing a strategy for dysbiosis reversal in translational research. Video Abstract.}, }
@article {pmid39106694, year = {2024}, author = {Su, S and Li, Z and Sun, Y and Gao, S and Gao, Q}, title = {The multifaceted role of TolA protein in promoting survival, biofilm formation and virulence of avian pathogenic Escherichia coli.}, journal = {Poultry science}, volume = {103}, number = {10}, pages = {104142}, pmid = {39106694}, issn = {1525-3171}, mesh = {Animals ; *Biofilms ; *Poultry Diseases/microbiology ; *Chickens ; *Escherichia coli Infections/veterinary/microbiology ; Virulence ; *Escherichia coli Proteins/genetics/metabolism ; *Escherichia coli/physiology/pathogenicity/genetics ; Bacterial Outer Membrane Proteins/genetics/metabolism ; Virulence Factors/genetics/metabolism ; }, abstract = {Avian pathogenic Escherichia coli (APEC) can spread beyond the intestines and cause systemic infections, leading to various clinical manifestations, including airsacculitis, pericarditis, perihepatitis and colisepticemia. The mechanisms facilitating this extraintestinal infections are not fully understood. In this study, we investigate how the tolA gene affects APEC virulence by encoding a protein involved in maintaining outer membrane integrity. We constructed a tolA deletion mutant of APEC strain E058 and evaluated its growth and survival in various environments, including in vitro cultures and in vivo infection models in chickens. We found that the motility-defective ΔtolA mutant exhibits reduced biofilm formation ability and weakened resistance to the environmental stresses, suggesting an important role for TolA in APEC's survival. The lack of tolA gene affects the bacterial ability to resist the host's immune system, such as complement-mediated serum killing or phagocytosis, as shown by the serum killing and macrophage phagocytosis assays. Additionally, in vivo infection studies using chickens demonstrated that the ΔtolA mutant displayed attenuated virulence, evidenced by reduced mortality and lower tissue bacterial burden. Reverse transcription quantitative real-time PCR (RT-qPCR) analysis revealed that inactivation of tolA led to downregulation of virulence genes associated with serum resistance (traT) and flagellar biosynthesis (fliR). Taken together, our findings demonstrate the multifaceted role of TolA protein in promoting the survival, immune evasion, biofilm formation, and virulence of APEC E058. This suggests that targeting TolA could potentially offer new strategies for combating APEC infections.}, }
@article {pmid39106464, year = {2024}, author = {Hapip, CA and Fischer, E and Feldman, TP and Brown, BL}, title = {Formation of Single-Species and Multispecies Biofilm by Isolates from Septic Transfusion Reactions in Platelet Bag Model.}, journal = {Emerging infectious diseases}, volume = {30}, number = {9}, pages = {1819-1828}, pmid = {39106464}, issn = {1080-6059}, mesh = {*Biofilms/growth &amp; development ; Humans ; *Platelet Transfusion/adverse effects ; *Blood Platelets/microbiology ; Bacteria/isolation &amp; purification ; Transfusion Reaction ; }, abstract = {During 2018-2021, eight septic transfusion reactions occurred from transfusion of platelet units contaminated with Acinetobacter spp., Staphylococcus saprophyticus, Leclercia adecarboxylata, or a combination of those environmental organisms. Whether biofilm formation contributed to evasion of bacterial risk mitigations, including bacterial culture, point-of-care testing, or pathogen-reduction technology, is unclear. We designed a 12-well plate-based method to evaluate environmental determinants of single-species and multispecies biofilm formation in platelets. We evaluated bacteria isolated from septic transfusion reactions for biofilm formation by using crystal violet staining and enumeration of adherent bacteria. Most combinations of bacteria had enhanced biofilm production compared with single bacteria. Combinations involving L. adecarboxylata had increased crystal violet biofilm production and adherent bacteria. This study demonstrates that transfusion-relevant bacteria can produce biofilms well together. More work is needed to clarify the effect of biofilms on platelet bacterial risk control strategies, but US Food and Drug Administration-recommended strategies remain acceptable.}, }
@article {pmid39105888, year = {2024}, author = {Norouzalinia, F and Asadpour, L and Mokhtary, M}, title = {Anti-microbial, anti-biofilm, and efflux pump inhibitory effects of ellagic acid-bonded magnetic nanoparticles against Escherichia coli isolates.}, journal = {International microbiology : the official journal of the Spanish Society for Microbiology}, volume = {}, number = {}, pages = {}, pmid = {39105888}, issn = {1618-1905}, abstract = {The spread of microbial resistance is a threat to public health. In this study, the anti-microbial, anti-biofilm, and efflux pump inhibitory effects of ellagic acid-loaded magnetic nanoparticles (Fe3O4NPs@EA) against beta-lactamase producing Escherichia coli isolates have been investigated. The effects of Fe3O4 NPs@EA on the growth inhibition of E. coli isolates were determined by disc diffusion method and determining the minimum inhibitory concentration was done using broth micro-dilution method. The anti-biofilm effect of nanoparticles was investigated using the microplate method. The efflux pump inhibitory effect of nanoparticles was investigated using cart-wheel method and by investigating the effect of nanoparticles on acrB and tolC genes expression levels. Fe3O4 NPs@EA showed anti-bacterial effects against test bacteria, and the MIC of these nanoparticles varied from 0.19 to 1.56 mg/mL. These nanoparticles caused a 43-62% reduction in biofilm formation of test bacteria compared to control. Furthermore, efflux pump inhibitory effect of these nanoparticles was confirmed at a concentration of 1/8 MIC, and the expression of acrB and tolC genes decreased in bacteria treated with 1/4 MIC Fe3O4 NPs@EA. According to the results, the use of nanoparticles containing ellagic acid can provide a basis for the development of new treatments against drug-resistant E. coli. This substance may improve the concentration of antibiotics in the bacterial cell and increase their effectiveness by inhibiting the efflux in E. coli isolates.}, }
@article {pmid39105738, year = {2024}, author = {Adams, CE and Spicer, SK and Gaddy, JA and Townsend, SD}, title = {Synthesis of a Phosphoethanolamine Cellulose Mimetic and Evaluation of Its Unanticipated Biofilm Modulating Properties.}, journal = {ACS infectious diseases}, volume = {10}, number = {9}, pages = {3245-3255}, pmid = {39105738}, issn = {2373-8227}, support = {R01 HD090061/HD/NICHD NIH HHS/United States ; P30 DK058404/DK/NIDDK NIH HHS/United States ; P30 EY008126/EY/NEI NIH HHS/United States ; P30 CA068485/CA/NCI NIH HHS/United States ; R35 GM133602/GM/NIGMS NIH HHS/United States ; U24 DK059637/DK/NIDDK NIH HHS/United States ; S10 OD028704/OD/NIH HHS/United States ; R01 AI134036/AI/NIAID NIH HHS/United States ; I01 BX005352/BX/BLRD VA/United States ; P30 DK020593/DK/NIDDK NIH HHS/United States ; }, mesh = {*Biofilms/drug effects ; *Cellulose/chemistry/pharmacology ; *Ethanolamines/chemistry/pharmacology ; Uropathogenic Escherichia coli/drug effects/physiology ; Bacterial Adhesion/drug effects ; }, abstract = {When coordinating and adhering to a surface, microorganisms produce a biofilm matrix consisting of extracellular DNA, lipids, proteins, and polysaccharides that are intrinsic to the survival of bacterial communities. Indeed, bacteria produce a variety of structurally diverse polysaccharides that play integral roles in the emergence and maintenance of biofilms by providing structural rigidity, adhesion, and protection from environmental stressors. While the roles that polysaccharides play in biofilm dynamics have been described for several bacterial species, the difficulty in isolating homogeneous material has resulted in few structures being elucidated. Recently, Cegelski and co-workers discovered that uropathogenic Escherichia coli (UPEC) secrete a chemically modified cellulose called phosphoethanolamine cellulose (pEtN cellulose) that plays a vital role in biofilm assembly. However, limited chemical tools exist to further examine the functional role of this polysaccharide across bacterial species. To address this critical need, we hypothesized that we could design and synthesize an unnatural glycopolymer to mimic the structure of pEtN cellulose. Herein, we describe the synthesis and evaluation of a pEtN cellulose glycomimetic which was generated using ring-opening metathesis polymerization. Surprisingly, the synthetic polymers behave counter to native pEtN cellulose in that the synthetic polymers repress biofilm formation in E. coli laboratory strain 11775T and UPEC strain 700415 with longer glycopolymers displaying greater repression. To evaluate the mechanism of action, changes in biofilm and cell morphology were visualized using high resolution field-emission gun scanning electron microscopy which further revealed changes in cell surface appendages. Our results suggest synthetic pEtN cellulose glycopolymers act as an antiadhesive and inhibit biofilm formation across E. coli strains, highlighting a potential new inroad to the development of bioinspired, biofilm-modulating materials.}, }
@article {pmid39104625, year = {2024}, author = {Stoddard, H and Kulas, D and Zolghadr, A and Aloba, S and Schaerer, LG and Putman, L and Valencia, I and Lacey, JA and Shonnard, DR and Techtmann, SM and Ong, RG}, title = {Biofilm mitigation in hybrid chemical-biological upcycling of waste polymers.}, journal = {Frontiers in bioengineering and biotechnology}, volume = {12}, number = {}, pages = {1435695}, pmid = {39104625}, issn = {2296-4185}, abstract = {Introduction: Accumulation of plastic waste in the environment is a serious global issue. To deal with this, there is a need for improved and more efficient methods for plastic waste recycling. One approach is to depolymerize plastic using pyrolysis or chemical deconstruction followed by microbial-upcycling of the monomers into more valuable products. Microbial consortia may be able to increase stability in response to process perturbations and adapt to diverse carbon sources, but may be more likely to form biofilms that foul process equipment, increasing the challenge of harvesting the cell biomass. Methods: To better understand the relationship between bioprocess conditions, biofilm formation, and ecology within the bioreactor, in this study a previously-enriched microbial consortium (LS1_Calumet) was grown on (1) ammonium hydroxide-depolymerized polyethylene terephthalate (PET) monomers and (2) the pyrolysis products of polyethylene (PE) and polypropylene (PP). Bioreactor temperature, pH, agitation speed, and aeration were varied to determine the conditions that led to the highest production of planktonic biomass and minimal formation of biofilm. The community makeup and diversity in the planktonic and biofilm states were evaluated using 16S rRNA gene amplicon sequencing. Results: Results showed that there was very little microbial growth on the liquid product from pyrolysis under all fermentation conditions. When grown on the chemically-deconstructed PET the highest cell density (0.69 g/L) with minimal biofilm formation was produced at 30°C, pH 7, 100 rpm agitation, and 10 sL/hr airflow. Results from 16S rRNAsequencing showed that the planktonic phase had higher observed diversity than the biofilm, and that Rhodococcus, Paracoccus, and Chelatococcus were the most abundant genera for all process conditions. Biofilm formation by Rhodococcus sp. And Paracoccus sp. Isolates was typically lower than the full microbial community and varied based on the carbon source. Discussion: Ultimately, the results indicate that biofilm formation within the bioreactor can be significantly reduced by optimizing process conditions and using pure cultures or a less diverse community, while maintaining high biomass productivity. The results of this study provide insight into methods for upcycling plastic waste and how process conditions can be used to control the formation of biofilm in bioreactors.}, }
@article {pmid39104345, year = {2024}, author = {Wei, ZC and Zhou, C and Ji, L and Hou, DQ and Dong, Y}, title = {[Comparison of the repair effects of Haiao oral biofilm alone or in combination with allogeneic bone graft in bone defects after jaw bone cyst surgery].}, journal = {Shanghai kou qiang yi xue = Shanghai journal of stomatology}, volume = {33}, number = {3}, pages = {285-289}, pmid = {39104345}, issn = {1006-7248}, mesh = {Humans ; *Bone Transplantation/methods ; *Biofilms/drug effects ; Prospective Studies ; Transplantation, Homologous/methods ; }, abstract = {PURPOSE: To compare the repair effects of Haiao oral biofilm alone or in combination with allogeneic bone graft on bone defects after jaw bone cyst surgery.<br><br>METHODS: A prospective study was conducted on 105 patients with bone defects after jaw bone cyst surgery who were admitted to Affiliated Hospital of Jiangnan University from November 2020 to July 2022. According to the random number table methods, the patients were divided into three groups: Haiao membrane group, allogeneic bone graft group and combination group. Among them, Haiao membrane group(35 patients) were repaired using Haiao oral biofilm; allogeneic bone group(35 patients) using allogeneic bone, while combined group (35 patients) using a combination of Haiao oral biofilm and allogeneic bone graft. The clinical basic data of three groups of patients were compared, including the healing effect at the incision, bone density at the bone defect, bone resorption and attachment loss. Statistical analysis was performed with SPSS 22.0 software package.<br><br>RESULTS: There was no significant difference in general clinical data among the three groups (P&#xff1e;0.05). The postoperative restoration effect of gingival soft tissue morphology in combined group was significantly better than that in Haiao membrane group and allogeneic bone graft group (P&#xff1c;0.05). There was no significant difference in bone density at the bone defect site among the three groups before treatment(P&#xff1e;0.05); 6 and 12 months after treatment, the bone density of the three groups was significantly improved (P&#xff1c;0.05), and combined group was significantly higher than the other groups(P&#xff1c;0.05). There was no significant difference in the vertical and lingual bone resorption levels among the three groups before treatment(P&#xff1e;0.05); 6 and 12 months after treatment, the vertical and lingual bone resorption levels of the three groups were significantly reduced (P&#xff1c;0.05), and combined group were significantly lower than the other groups (P&#xff1c;0.05). There was no significant difference in attachment loss among the three groups before treatment(P&#xff1e;0.05); 6 and 12 months after treatment, the attachment loss of the three groups decreased(P&#xff1c;0.05), and combined group was significantly lower than the other groups(P&#xff1c;0.05).<br><br>CONCLUSIONS: The combination of Haiao oral biofilm and allogeneic bone graft has good repair effect in the treatment of bone defects after jaw bone cyst surgery, which is beneficial for the recovery of gingival soft tissue, improvement of bone density, reduction of bone resorption and attachment loss.}, }
@article {pmid39104344, year = {2024}, author = {Zhang, MZ and Kuang, HF and Yang, LY and Luo, W}, title = {[Application of small intestinal submucosa absorbable biofilm in the repair of alveolar bone defects].}, journal = {Shanghai kou qiang yi xue = Shanghai journal of stomatology}, volume = {33}, number = {3}, pages = {279-284}, pmid = {39104344}, issn = {1006-7248}, mesh = {Humans ; *Biofilms ; *Intestinal Mucosa ; Alveolar Bone Loss ; Bone Regeneration ; Intestine, Small ; Absorbable Implants ; }, abstract = {PURPOSE: To study the clinical efficacy of small intestinal submucosa (SIS) absorbable biological membrane in alveolar bone defect repair.<br><br>METHODS: A total of 102 patients with alveolar bone defect who received guided bone regeneration (GBR) in our hospital from January 2020 to January 2022 were selected and divided into Bio-Gide group (51 cases using Bio-Gide absorbable biofilm) and SIS group (51 cases using SIS absorbable biofilm) by computer random number generator. The perioperative related indicators, blood calcium, blood phosphorus, biocompatibility, periodontal attachment loss (PAL) length, pulp sensitivity, tooth mobility, alveolar bone volume and adverse events of the two groups were compared. Statistical analysis was performed with SPSS 24.0 software package.<br><br>RESULTS: There was no significant difference in operation time, intraoperative blood loss, visual analogue scale (VAS) score of pain on the first day after operation, VAS score on the fifth day after operation, wound healing time, blood calcium and phosphorus levels before operation, 1 d and 12 d after operation, PAL length before operation, 3 months, 6 months and 12 months after operation, pulp sensitivity and tooth looseness grade 1 and 2 percentage at 3, 6 and 12 months after operation, bone width increase, bone height increase at 12 months after operation and adverse event rate between the two groups (P&#xff1e;0.05). Compared with Bio-Gide group, the wound healing time and biofilm absorption time were shortened in SIS group(P&#xff1c;0.05), and the incidence of rejection was decreased 12 d after operation (P&#xff1c;0.05).<br><br>CONCLUSIONS: SIS absorbable biofilm and Bio-Gide absorbable biofilm have similar efficacy and safety in repairing GBR for alveolar bone defects, but the former is more biocompatible and the latter can provide longer barrier function.}, }
@article {pmid39102953, year = {2024}, author = {Zhao, Y and Yuan, X and Du, Z and Niu, J and Song, J and Zhai, S and Liu, Y and Nuramkhaan, M}, title = {New insights into N2O emission and electron competition under different chemical oxygen demand to nitrogen ratios in a biofilm system.}, journal = {The Science of the total environment}, volume = {949}, number = {}, pages = {175265}, doi = {10.1016/j.scitotenv.2024.175265}, pmid = {39102953}, issn = {1879-1026}, mesh = {*Biofilms ; *Nitrous Oxide/metabolism ; *Nitrogen/metabolism ; *Biological Oxygen Demand Analysis ; Denitrification ; Bioreactors ; Electrons ; Waste Disposal, Fluid/methods ; Air Pollutants ; Models, Theoretical ; }, abstract = {Nitrous oxide (N2O) is a greenhouse gas that could accumulate during the heterotrophic denitrification process. In this study, the effects of different chemical oxygen demand to nitrogen ratio (COD/N) on N2O production and electron competition was investigated. The electron competition was intensified with the decrease of electron supply, and Nos had the best electron competition ability. The model simulation results indicated that the degradation of NOx-Ns was a combination of diffusion and biological degradation. As reaction proceeding, N2O could accumulate inside biofilm. A thinner biofilm and a longer hydraulic retention time (HRT) might be an effective way to control N2O emission. The application of mathematical model is an opportunity to gain deep understanding of substrate degradation and electron competition inside biofilm.}, }
@article {pmid39102390, year = {2024}, author = {Rimi, SS and Ashraf, MN and Sigma, SH and Ahammed, MT and Siddique, MP and Zinnah, MA and Rahman, MT and Islam, MS}, title = {Biofilm formation, agr typing and antibiotic resistance pattern in methicillin-resistant Staphylococcus aureus isolated from hospital environments.}, journal = {PloS one}, volume = {19}, number = {8}, pages = {e0308282}, pmid = {39102390}, issn = {1932-6203}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Methicillin-Resistant Staphylococcus aureus/genetics/drug effects/isolation &amp; purification/physiology ; *Bacterial Proteins/genetics ; Humans ; Anti-Bacterial Agents/pharmacology ; Hospitals ; Microbial Sensitivity Tests ; Trans-Activators/genetics ; Staphylococcal Infections/microbiology ; }, abstract = {Biofilm development significantly enhances the virulence of methicillin-resistant Staphylococcus aureus (MRSA), leading to severe infections and decreased susceptibility to antibiotics, especially in strains associated with hospital environments. This study examined the occurrence of MRSA, their ability to form biofilms, agr typing, and the antibiotic resistance profiles of biofilm-forming MRSA strains isolated from environmental surfaces at Mymensingh Medical College Hospital (MMCH). From 120 swab samples, 86 (71.67%) tested positive for S. aureus. MRSA was identified in 86 isolates using the disk diffusion technique, and by polymerase chain reaction (PCR), 56 (65.1%) isolates were confirmed to carry the mecA gene. The Crystal Violet Microtiter Plate (CVMP) test revealed that 80.35% (45 isolates) were biofilm-forming and 19.6% (11 isolates) were non-biofilm-forming. Out of 45 biofilm producer isolates 37.5% and 42.9% isolates exhibited strong and intermediate biofilm-forming characteristics, respectively. Molecular analysis revealed that 17.78% of MRSA isolates carried at least one gene related to biofilm formation, specifically icaA, icaB, and icaD genes were discovered in 13.33%, 8.89%, 6.67% of the MRSA isolates, respectively. In agr typing, the most prevalent group was agr I (71.11%), followed by group III (17.78%) and group II (11.11%). Group IV was not detected. The distribution of agr gene groups showed a significant difference among biofilm-forming isolates (p < 0.05). In agr group I, 18.75% of isolates carried the icaA gene, 12.5% carried the icaB gene, and 9.37% carried the icaD gene. Biofilm-forming genes were not detected in any of the isolates from agr groups II or III. There are no statistically significant differences between agr groups and the presence of these genes (p > 0.05). Antibiotic resistance varied significantly among agr groups, with agr group I displaying the highest resistance, agr group II, and agr group III exhibiting the least resistance (p < 0.05). Seventy-three (73.3%) of the isolates were multi-drug resistant, with agr group I displaying nineteen MDR patterns. The occurrence of MRSA in hospital environments and their capacity to form biofilm raises concerns for public health. These findings support the importance of further research focused on agr quorum sensing systems as a basis for developing novel antibacterial agents.}, }
@article {pmid39101559, year = {2024}, author = {Brar, NK and Dhariwal, A and Shekhar, S and Junges, R and Hakansson, AP and Petersen, FC}, title = {HAMLET, a human milk protein-lipid complex, modulates amoxicillin induced changes in an ex vivo biofilm model of the oral microbiome.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1406190}, pmid = {39101559}, issn = {1664-302X}, abstract = {Challenges from infections caused by biofilms and antimicrobial resistance highlight the need for novel antimicrobials that work in conjunction with antibiotics and minimize resistance risk. In this study we investigated the composite effect of HAMLET (human alpha-lactalbumin made lethal to tumor cells), a human milk protein-lipid complex and amoxicillin on microbial ecology using an ex vivo oral biofilm model with pooled saliva samples. HAMLET was chosen due to its multi-targeted antimicrobial mechanism, together with its synergistic effect with antibiotics on single species pathogens, and low risk of resistance development. The combination of HAMLET and low concentrations of amoxicillin significantly reduced biofilm viability, while each of them alone had little or no impact. Using a whole metagenomics approach, we found that the combination promoted a remarkable shift in overall microbial composition compared to the untreated samples. A large proportion of the bacterial species in the combined treatment were Lactobacillus crispatus, a species with probiotic effects, whereas it was only detected in a minor fraction in untreated samples. Although resistome analysis indicated no major shifts in alpha-diversity, the results showed the presence of TEM beta-lactamase genes in low proportions in all treated samples but absence in untreated samples. Our study illustrates HAMLET's capability to alter the effects of amoxicillin on the oral microbiome and potentially favor the growth of selected probiotic bacteria when in combination. The findings extend previous knowledge on the combined effects of HAMLET and antibiotics against target pathogens to include potential modulatory effects on polymicrobial biofilms of human origin.}, }
@article {pmid39101130, year = {2024}, author = {Vasconcelos, PGS and Lee, KM and Abuna, GF and Costa, EMMB and Murata, RM}, title = {Monoterpene antifungal activities: evaluating geraniol, citronellal, and linalool on Candida biofilm, host inflammatory responses, and structure-activity relationships.}, journal = {Frontiers in pharmacology}, volume = {15}, number = {}, pages = {1394053}, pmid = {39101130}, issn = {1663-9812}, support = {R03 DE031190/DE/NIDCR NIH HHS/United States ; }, abstract = {Introduction: Despite the rising concern with fungal resistance, a myriad of molecules has yet to be explored. Geraniol, linalool, and citronellal are monoterpenes with the same molecular formula (C10H18O), however, neither the effect of these compounds on inflammatory axis induced by Candida spp. nor the antibiofilm Structure-Activity Relationship (SAR) have been well-investigated. Herein we analyzed geraniol, linalool and citronellal antifungal activity, cytotoxicity, and distinctive antibiofilm SAR, also the influence of geraniol on Candida spp induced dysregulated inflammatory axis, and in vivo toxicity. Methods: Minimal inhibitory (MIC) and fungicidal (MFC) concentrations against Candida spp were defined, followed by antibiofilm activity (CFU-colony forming unit/mL/g of dry weight). Cytotoxic activity was assessed using human monocytes (THP-1) and oral squamous cell (TR146). Geraniol was selected for further analysis based on antifungal, antibiofilm and cytotoxic results. Geraniol was tested using a dual-chamber co-culture model with TR146 cells infected with C. albicans, and THP-1 cells, used to mimic oral epithelium upon fungal infection. Expression of Candida enzymes (phospholipase-PLB and aspartyl proteases-SAP) and host inflammatory cytokines (interleukins: IL-1β, IL-6, IL-17, IL-18, IL-10, and Tumor necrosis factor-TNF) were analyzed. Lastly, geraniol in vivo toxicity was assessed using Galleria mellonella. Results: MIC values obtained were 1.25-5 mM/mL for geraniol, 25-100 mM/mL for linalool, and 100-200 mM/mL for citronellal. Geraniol 5 and 50 mM/mL reduced yeast viability during biofilm analysis, only 500 mM/mL of linalool was effective against a 72 h biofilm and no biofilm activity was seen for citronellal. LD50 for TR146 and THP-1 were, respectively: geraniol 5.883 and 8.027 mM/mL; linalool 1.432 and 1.709 mM/mL; and citronellal 0.3006 and 0.1825 mM/mL. Geraniol was able to downregulate expression of fungal enzymes and host pro-inflammatory cytokines IL-1β, IL-6, and IL-18. Finally, safety in vivo parameters were observed up to 20 mM/Kg. Discussion: Despite chemical similarities, geraniol presented better antifungal, antibiofilm activity, and lower cytotoxicity when compared to the other monoterpenes. It also showed low in vivo toxicity and capacity to downregulate the expression of fungal enzymes and host pro-inflammatory cytokines. Thus, it can be highlighted as a viable option for oral candidiasis treatment.}, }
@article {pmid39099204, year = {2024}, author = {Algadi, H and Alhoot, MA and Al-Maleki, AR and Purwitasari, N}, title = {Effects of Metal and Metal Oxide Nanoparticles against Biofilm-Forming Bacteria: A Systematic Review.}, journal = {Journal of microbiology and biotechnology}, volume = {34}, number = {9}, pages = {1748-1756}, pmid = {39099204}, issn = {1738-8872}, mesh = {*Biofilms/drug effects ; *Metal Nanoparticles/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Bacteria/drug effects ; *Oxides/pharmacology/chemistry ; Metals/pharmacology/chemistry ; Microbial Sensitivity Tests ; }, abstract = {Biofilm formation by bacteria poses a significant challenge across diverse industries, displaying resilience against conventional antimicrobial agents. Nanoparticles emerge as a promising alternative for addressing biofilm-related issues. This review aims to assess the efficacy of metal and metal oxide nanoparticles in inhibiting or disrupting biofilm formation by various bacterial species. It delineates trends, identifies gaps, and outlines avenues for future research, emphasizing best practices and optimal nanoparticles for biofilm prevention and eradication. Additionally, it underscores the potential of nanoparticles as substitutes for traditional antibiotics in healthcare and combating antibiotic resistance. A systematic literature search, encompassing Web of Science, PubMed, and Google Scholar from 2015 to 2023, yielded 48 publications meeting the review criteria. These studies employed diverse methods to explore the antibacterial activity of nanoparticles against biofilm-forming bacteria strains. The implications of this study are profound, offering prospects for novel antimicrobial agents targeting biofilm-forming bacteria, often resistant to conventional antibiotics. In conclusion, nanoparticles present a promising frontier in countering biofilm-forming bacteria. This review delivers a structured analysis of current research, providing insights into the potential and challenges of nanoparticle utilization against biofilm-related challenges. While nanoparticles exhibit inherent antimicrobial properties with applications spanning healthcare, agriculture, and industries, the review acknowledges limitations such as the narrow scope of tested nanoparticles and the imperative need for extensive research on long-term toxicity and environmental impacts.}, }
@article {pmid39098403, year = {2024}, author = {Stindlova, M and Peroutka, V and Jencova, V and Havlickova, K and Lencova, S}, title = {Application of MTT assay for probing metabolic activity in bacterial biofilm-forming cells on nanofibrous materials.}, journal = {Journal of microbiological methods}, volume = {224}, number = {}, pages = {107010}, doi = {10.1016/j.mimet.2024.107010}, pmid = {39098403}, issn = {1872-8359}, mesh = {*Biofilms/growth &amp; development ; *Staphylococcus aureus/physiology ; *Nanofibers/chemistry ; *Escherichia coli/physiology ; *Tetrazolium Salts/metabolism/chemistry ; *Polyesters/chemistry ; Thiazoles/metabolism ; Glucose/metabolism ; Spectrophotometry/methods ; Nylons/chemistry ; }, abstract = {The quantification of cellular metabolic activity via MTT assay has become a widespread practice in eukaryotic cell studies and is progressively extending to bacterial cell investigations. This study pioneers the application of MTT assay to evaluate the metabolic activity of biofilm-forming cells within bacterial biofilms on nanofibrous materials. The biofilm formation of Staphylococcus aureus and Escherichia coli on nanomaterials electrospun from polycaprolactone (PCL), polylactic acid (PLA), and polyamide (PA) was examined. Various parameters of the MTT assay were systematically investigated, including (i) the dissolution time of the formed formazan, (ii) the addition of glucose, and (iii) the optimal wavelength for spectrophotometric determination. Based on interim findings, a refined protocol suitable for application to nanofibrous materials was devised. We recommend 2 h of the dissolution, the application of glucose, and spectrophotometric measurement at 595 nm to obtain reliable data. Comparative analysis with the reference CFU counting protocol revealed similar trends for both tested bacteria and all tested nanomaterials. The proposed MTT protocol emerges as a suitable method for assessing the metabolic activity of bacterial biofilms on PCL, PLA, and PA nanofibrous materials.}, }
@article {pmid39098160, year = {2024}, author = {Kim, U and Oh, SW}, title = {Antimicrobial resistance induction potential of grapefruit seed extract on multi-species biofilm of E. coli in food industry.}, journal = {International journal of food microbiology}, volume = {424}, number = {}, pages = {110849}, doi = {10.1016/j.ijfoodmicro.2024.110849}, pmid = {39098160}, issn = {1879-3460}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Citrus paradisi ; *Microbial Sensitivity Tests ; *Escherichia coli/drug effects/growth &amp; development ; *Seeds ; *Plant Extracts/pharmacology ; *Anti-Bacterial Agents/pharmacology ; *Listeria monocytogenes/drug effects/growth &amp; development/physiology ; Drug Resistance, Bacterial ; Food Microbiology ; Salmonella typhimurium/drug effects ; }, abstract = {Biofilm formation in natural environments involving complex multi-structural arrangements hinders challenges in antimicrobial resistance. This study investigated the antimicrobial resistance potential of grapefruit seed extract (GSE) by examining the formation of mono-, dual-, and multi-species biofilms. We also explored the counterintuitive effect in response to GSE at various concentrations, including minimum inhibitory concentration (MIC) and sub-MIC (1/2 and 1/4 MIC). The results of the swimming and swarming motility tests revealed increased motility at the sub-MIC of GSE. The crystal violet assay demonstrated increased biofilm formation in multi-species biofilms, highlighting the synergistic effect of Escherichia coli, Salmonella Typhimurium, and Listeria monocytogenes. At the MIC concentration of GSE, field emission scanning electron microscopy (FE-SEM) revealed cell morphology damage, while sub-MIC increased biofilm formation and architectural complexity. Multi-species biofilms demonstrated greater biofilm-forming ability and antimicrobial resistance than mono-species biofilms, indicating synergistic interactions and enhanced resilience. These findings highlight the importance of understanding biofilm dynamics and antimicrobial resistance to ensure environmental safety.}, }
@article {pmid39098095, year = {2024}, author = {Xu, S and Liu, Z and Ren, P and Liu, Y and Xiao, F and Li, W}, title = {BmfR, a novel GntR family regulator, regulates biofilm formation in marine-derived, Bacillus methylotrophicus B-9987.}, journal = {Microbiological research}, volume = {287}, number = {}, pages = {127859}, doi = {10.1016/j.micres.2024.127859}, pmid = {39098095}, issn = {1618-0623}, mesh = {*Bacillus/genetics/metabolism ; *DNA-Binding Proteins/genetics/metabolism ; *Bacterial Proteins/genetics/metabolism ; *Biofilms ; Gene Expression Regulation, Bacterial ; Transcriptome ; Operon ; Base Sequence ; Sequence Homology, Nucleic Acid ; Polysaccharides/metabolism ; Extracellular Space/metabolism ; }, abstract = {Biofilms are common living states for microorganisms, allowing them to adapt to environmental changes. Numerous Bacillus strains can form complex biofilms that play crucial roles in biocontrol processes. However, our current understanding of the molecular mechanisms of biofilm formation in Bacillus is mainly based on studies of Bacillus subtilis. Knowledge regarding the biofilm formation of other Bacillus species remains limited. In this study, we identified a novel transcriptional regulator, BmfR, belonging to the GntR family, that regulates biofilm formation in marine-derived Bacillus methylotrophicus B-9987. We demonstrated that BmfR induces biofilm formation by activating the extracellular polysaccharide structural genes epsA-O and negatively regulating the matrix gene repressor, SinR; of note it positively affects the expression of the master regulator of sporulation, Spo0A. Furthermore, database mining for BmfR homologs has revealed their widespread distribution among many bacterial species, mainly Firmicutes and Proteobacteria. This study advances our understanding of the biofilm regulatory network of Bacillus strains, and provides a new target for exploiting and manipulating biofilm formation.}, }
@article {pmid39098075, year = {2024}, author = {Liu, H and Li, L and Ye, W and Zhao, B and Peng, Y and Liu, G and Gao, X and Peng, X}, title = {Simultaneous nitrification and denitrification in a hybrid activated sludge-membrane aerated biofilm reactor (H-MABR) for nitrogen removal from low COD/N interflow: A pilot-scale study.}, journal = {Journal of environmental management}, volume = {367}, number = {}, pages = {122038}, doi = {10.1016/j.jenvman.2024.122038}, pmid = {39098075}, issn = {1095-8630}, mesh = {*Bioreactors ; *Nitrogen/metabolism ; *Denitrification ; *Nitrification ; *Biofilms ; *Sewage ; *Biological Oxygen Demand Analysis ; Waste Disposal, Fluid/methods ; Pilot Projects ; }, abstract = {There are a large number of simple landfills in hilly areas, and the results of previous studies have shown that pollutants in landfills can spread via interflow and cause surface source pollution. The hybrid activated sludge-membrane aerated bioreactor (H-MABR) developed in a previous study can be used for the treatment of interflow with a low chemical oxygen demand (COD)/total nitrogen (TN) ratio, and it has been shown to be effective in laboratory simulations. To investigate the effectiveness of the H-MABR in treating interflow around landfills in real-world applications, an in-situ pilot-scale evaluation of the effectiveness of H-MABR operation was conducted at a landfill. The results indicated that the removal efficiencies of COD, TN, and ammonia nitrogen in interflow by H-MABR were 87.1 ± 6.0%, 80.9 ± 7.9%, and 97.9 ± 1.4%, respectively. The removal rate of TN reached 148.6-205.6 g-N/m[3]·d. The concentration of each pollutant in the effluent was in accordance with China's "Standard for pollution control on the landfill site of municipal solid waste (GB16889-2008)," wherein the COD, TN, and ammonia nitrogen of effluent should be less than 100 mg/L, 40 mg/L, and 25 mg/L, respectively. The results of community composition analysis and PICRUSt analysis based on 16S rRNA gene sequencing showed that there were different dominant functional bacteria between the inner and outer rings, but functional genes involved in the nitrification-denitrification, assimilated nitrate reduction, and dissimilated nitrate reduction pathway were all detected. Furthermore, except for the nitrite oxidation gene narG, the abundance of which did not significantly differ between the inner and outer rings, the abundance of the other functional genes was higher in the outer ring than in the inner ring. An economic evaluation revealed that the operation cost of interflow treatment by the H-MABR was as low as ¥2.78/m[3]; thus, the H-MABR is a shock-load-resistant and cost-effective technology for interflow treatment.}, }
@article {pmid39097900, year = {2024}, author = {Taha Majid, B and Ali Hussein, S and Kamal Rachid, S}, title = {Unraveling the molecular regulation of biofilm underlying effect of chronic disease medications.}, journal = {Cellular and molecular biology (Noisy-le-Grand, France)}, volume = {70}, number = {7}, pages = {15-21}, doi = {10.14715/cmb/2024.70.7.3}, pmid = {39097900}, issn = {1165-158X}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Staphylococcus aureus/drug effects/genetics/physiology ; Humans ; *Enterococcus faecalis/drug effects/genetics/physiology ; *Ursodeoxycholic Acid/pharmacology ; Anti-Bacterial Agents/pharmacology ; Chronic Disease ; Microbial Sensitivity Tests ; Gene Expression Regulation, Bacterial/drug effects ; Benzimidazoles/pharmacology ; Tetrazoles/pharmacology ; Biphenyl Compounds/pharmacology ; }, abstract = {A biofilm is a complex microbial structure that promotes the progression of persistent infections, particularly in nosocomial settings via indwelling medical devices. Conventional antibiotics are often ineffective treatments for biofilms; hence, it is crucial to investigate or design non-antibiotic antibiofilm compounds that can successfully reduce and eradicate biofilm-related infections. This study was an attempt to repurpose chronic disease medications of the antihypertensive and antilipidemic drug classes, including candesartan cilexetil (CC) and ursodeoxycholic acid (UDCA), respectively, to be used as antibiofilm agents against the two infectious pathogens Staphylococcus aureus and Enterococcus faecalis. Crystal violet (CV) staining assay was used to evaluate the antibiofilm activity of the drugs. Real-time polymerase chain reaction (RT-PCR) was performed to determine the transcription levels of the biofilm-related genes (icaA and icaR in S. aureus and fsrC and gelE in E. faecalis) following treatment with different concentrations of CC and UDCA. we found that a concentration of greater than 1.5 µg/ml of CC significantly (p < 0.005) inhibited the biofilm formation of both bacterial isolates, and a concentration of greater than 50 µg/ml of UDCA significantly (p < 0.005) inhibited the biofilm formation of both bacterial isolates. Interestingly, the mRNA expression levels of biofilm-related genes were decreased in the two bacterial isolates at concentrations that were lower than the human pharmaceutical daily doses.}, }
@article {pmid39097145, year = {2024}, author = {Bhandari, S and Upreti, MK and Angbuhang, KB and Shrestha, B and Thapa Shrestha, U}, title = {Increased biofilm-associated carbapenem-resistant Acinetobacter calcoaceticus-baumannii complex infections among hospitalised patients in Kathmandu Model Hospital, Nepal.}, journal = {Journal of global antimicrobial resistance}, volume = {39}, number = {}, pages = {1-2}, doi = {10.1016/j.jgar.2024.07.012}, pmid = {39097145}, issn = {2213-7173}, }
@article {pmid39097132, year = {2024}, author = {Valdivia Pérez, JA and Nocelli, NE and Bustos, J and Antonio, ML and Smania, A and Vico, RV and Fanani, ML}, title = {Membrane-targeted mechanism for amphiphilic vitamin C compounds as methicillin-resistant Staphylococcus aureus biofilm eradicating agents.}, journal = {Chemistry and physics of lipids}, volume = {264}, number = {}, pages = {105423}, doi = {10.1016/j.chemphyslip.2024.105423}, pmid = {39097132}, issn = {1873-2941}, mesh = {*Biofilms/drug effects ; *Methicillin-Resistant Staphylococcus aureus/drug effects ; *Ascorbic Acid/chemistry/pharmacology ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Microbial Sensitivity Tests ; Cell Membrane/drug effects/metabolism/chemistry ; Surface-Active Agents/chemistry/pharmacology ; }, abstract = {Staphylococcus aureus infections and its biofilm removal is an important concern in health care management. Methicillin-resistant S. aureus is responsible for severe morbidity and mortality worldwide. The extensive use of disinfectants against biofilms has led to negative environmental impacts. Developing new and more potent biofilm eradication agents with minimal detrimental effects on human and environmental health is currently on the agenda. The alkyl esters of L-ascorbic acid (ASCn) are antioxidant amphiphiles, which show antimicrobial capacity against methicillin-sensitive and resistant S. aureus strains. ASC12 and ASC14 formulations are able to kill the persister cells of the deepest layers of the biofilm. We tested the hypothesis that the antimicrobial and antibiofilm capacity found for the ASCn emerges from a combined effect of its amphiphilic and their redox capacity. This mechanism appears related to: I) a larger diffusion capacity of the ASC12 micelles than ASC14 and ASC16 microstructures; II) the neutralization of the ASCn acid hydroxyl when the amphiphile reaches the surface of an anionic surface, followed by a rapid insertion; III) the disruption of cell membrane by alteration of membrane tension and structure and IV) ASCn accumulation in the cell membrane or biofilm extracellular matrix surfaces, reducing functional chemical groups and affecting its biological function.}, }
@article {pmid39097126, year = {2024}, author = {Li, J and Sun, M and Tang, X and Liu, Y and Ou, C and Luo, Y and Wang, L and Hai, L and Deng, L and He, D}, title = {Acidic biofilm microenvironment-responsive ROS generation via a protein nanoassembly with hypoxia-relieving and GSH-depleting capabilities for efficient elimination of biofilm bacteria.}, journal = {Acta biomaterialia}, volume = {186}, number = {}, pages = {439-453}, doi = {10.1016/j.actbio.2024.07.044}, pmid = {39097126}, issn = {1878-7568}, mesh = {*Biofilms/drug effects ; Animals ; *Copper/chemistry/pharmacology ; *Glutathione/metabolism ; *Serum Albumin, Bovine/chemistry ; *Reactive Oxygen Species/metabolism ; *Indocyanine Green/chemistry/pharmacology ; Hydrogen Peroxide/chemistry ; Mice ; Anti-Bacterial Agents/pharmacology/chemistry ; Staphylococcus aureus/drug effects/physiology ; Hydrogen-Ion Concentration ; }, abstract = {Reactive oxygen species (ROS) are widely considered to the effective therapeutics for fighting bacterial infections especially those associated with biofilm. However, biofilm microenvironments including hypoxia, limited H2O2, and high glutathione (GSH) level seriously limit the therapeutic efficacy of ROS-based strategies. Herein, we have developed an acidic biofilm microenvironment-responsive antibacterial nanoplatform consisting of copper-dopped bovine serum albumin (CBSA) loaded with copper peroxide (CuO2) synthesized in situ and indocyanine green (ICG). The three-in-one nanotherapeutics (CuO2/ICG@CBSA) are capable of releasing Cu[2+] and H2O2 in a slightly acidic environment, where Cu[2+] catalyzes the conversion of H2O2 into hydroxyl radical (•OH) and consumes the highly expressed GSH to disrupt the redox homeostasis. With the assistance of an 808 nm laser, the loaded ICG not only triggers the production of singlet oxygen ([1]O2) by a photodynamic process, but also provides photonic hyperpyrexia that further promotes the Fenton-like reaction for enhancing •OH production and induces thermal decomposition of CuO2 for the O2-self-supplying [1]O2 generation. The CuO2/ICG@CBSA with laser irradiation demonstrates photothermal-augmented multi-mode synergistic bactericidal effect and is capable of inhibiting biofilm formation and eradicating the biofilm bacteria. Further in vivo experiments suggest that the CuO2/ICG@CBSA can effectively eliminate wound infections and accelerate wound healing. The proposed three-in-one nanotherapeutics with O2/H2O2-self-supplied ROS generating capability show great potential in treating biofilm-associated bacterial infections. STATEMENT OF SIGNIFICANCE: Here, we have developed an acidic biofilm microenvironment-responsive nanoplatform consisting of copper-dopped bovine serum albumin (CBSA) loaded with copper peroxide (CuO2) synthesized in situ and indocyanine green (ICG). The nanotherapeutics (CuO2/ICG@CBSA) are capable of releasing Cu[2+] and H2O2 in an acidic environment, where Cu[2+] catalyzes the conversion of H2O2 into •OH and consumes the overexpressed GSH to improve oxidative stress. With the aid of an 808 nm laser, ICG provides photonic hyperpyrexia for enhancing •OH production, and triggers O2-self-supplying [1]O2 generation. CuO2/ICG@CBSA with laser irradiation displays photothermal-augmented multi-mode antibacterial and antibiofilm effect. Further in vivo experiments prove that CuO2/ICG@CBSA effectively eliminates wound infection and promotes wound healing. The proposed three-in-one nanotherapeutics show great potential in treating biofilm-associated bacterial infections.}, }
@article {pmid39096840, year = {2025}, author = {Huo, S and Lyu, Z and Wang, X and Liu, S and Chen, X and Yang, M and Liu, Z and Yin, X}, title = {Engineering mesoporous polydopamine-based potentiate STING pathway activation for advanced anti-biofilm therapy.}, journal = {Biomaterials}, volume = {312}, number = {}, pages = {122739}, doi = {10.1016/j.biomaterials.2024.122739}, pmid = {39096840}, issn = {1878-5905}, mesh = {*Biofilms/drug effects ; *Polymers/chemistry ; Animals ; *Indoles/chemistry/pharmacology ; Mice ; *Membrane Proteins/metabolism ; Nanoparticles/chemistry ; Photochemotherapy/methods ; Porosity ; Macrophages/metabolism/drug effects ; Reactive Oxygen Species/metabolism ; Female ; Signal Transduction/drug effects ; Photothermal Therapy ; Myeloid-Derived Suppressor Cells/metabolism/drug effects ; Mice, Inbred C57BL ; }, abstract = {The biofilm-induced "relatively immune-compromised zone" creates an immunosuppressive microenvironment that is a significant contributor to refractory infections in orthopedic endophytes. Consequently, the manipulation of immune cells to co-inhibit or co-activate signaling represents a crucial strategy for the management of biofilm. This study reports the incorporation of Mn[2+] into mesoporous dopamine nanoparticles (Mnp) containing the stimulator of interferon genes (STING) pathway activator cGAMP (Mncp), and outer wrapping by M1-like macrophage cell membrane (m-Mncp). The cell membrane enhances the material's targeting ability for biofilm, allowing it to accumulate locally at the infectious focus. Furthermore, m-Mncp mechanically disrupts the biofilm through photothermal therapy and induces antigen exposure through photodynamic therapy-generated reactive oxygen species (ROS). Importantly, the modulation of immunosuppression and immune activation results in the augmentation of antigen-presenting cells (APCs) and the commencement of antigen presentation, thereby inducing biofilm-specific humoral immunity and memory responses. Additionally, this approach effectively suppresses the activation of myeloid-derived suppressor cells (MDSCs) while simultaneously boosting the activity of T cells. Our study showcases the efficacy of utilizing m-Mncp immunotherapy in conjunction with photothermal and photodynamic therapy to effectively mitigate residual and recurrent infections following the extraction of infected implants. As such, this research presents a viable alternative to traditional antibiotic treatments for biofilm that are challenging to manage.}, }
@article {pmid39095741, year = {2024}, author = {Al-Momani, H and Aolymat, I and Ibrahim, L and Albalawi, H and Al Balawi, D and Albiss, BA and Almasri, M and Alghweiri, S}, title = {Low-dose zinc oxide nanoparticles trigger the growth and biofilm formation of Pseudomonas aeruginosa: a hormetic response.}, journal = {BMC microbiology}, volume = {24}, number = {1}, pages = {290}, pmid = {39095741}, issn = {1471-2180}, mesh = {*Pseudomonas aeruginosa/drug effects/genetics/physiology/growth &amp; development ; *Zinc Oxide/pharmacology ; *Biofilms/drug effects/growth &amp; development ; *Anti-Bacterial Agents/pharmacology ; *Hormesis/drug effects ; Humans ; Metal Nanoparticles/chemistry ; Nanoparticles/chemistry ; Cystic Fibrosis/microbiology ; Gene Expression Regulation, Bacterial/drug effects ; X-Ray Diffraction ; Pseudomonas Infections/microbiology ; Microbial Sensitivity Tests ; Microscopy, Electron, Scanning ; Dose-Response Relationship, Drug ; }, abstract = {INTRODUCTION: Hormesis describes an inverse dose-response relationship, whereby a high dose of a toxic compound is inhibitory, and a low dose is stimulatory. This study explores the hormetic response of low concentrations of zinc oxide nanoparticles (ZnO NPs) toward Pseudomonas aeruginosa.<br><br>METHOD: Samples of P. aeruginosa, i.e. the reference strain, ATCC 27,853, together with six strains recovered from patients with cystic fibrosis, were exposed to ten decreasing ZnO NPs doses (0.78-400&#xa0;&#xb5;g/mL). The ZnO NPs were manufactured from Peganum harmala using a chemical green synthesis approach, and their properties were verified utilizing X-ray diffraction and scanning electron microscopy. A microtiter plate technique was employed to investigate the impact of ZnO NPs on the growth, biofilm formation and metabolic activity of P. aeruginosa. Real-time polymerase chain reactions were performed to determine the effect of ZnO NPs on the expression of seven biofilm-encoding genes.<br><br>RESULT: The ZnO NPs demonstrated concentration-dependent bactericidal and antibiofilm efficiency at concentrations of 100-400&#xa0;&#xb5;g/mL. However, growth was significantly stimulated at ZnO NPs concentration of 25&#xa0;&#xb5;g/mL (ATCC 27853, Pa 3 and Pa 4) and at 12.5&#xa0;&#xb5;g/mL and 6.25&#xa0;&#xb5;g/mL (ATCC 27853, Pa 2, Pa 4 and Pa 5). No significant positive growth was detected at dilutions&#x2009;<&#x2009;6.25&#xa0;&#xb5;g/mL. similarly, biofilm formation was stimulated at concentration of 12.5&#xa0;&#xb5;g/mL (ATCC 27853 and Pa 1) and at 6.25&#xa0;&#xb5;g/mL (Pa 4). At concentration of 12.5&#xa0;&#xb5;g/mL, ZnO NPs upregulated the expression of LasB (ATCC 27853, Pa 1 and Pa 4) and LasR and LasI (ATCC 27853 and Pa 1) as well as RhII expression (ATCC 27853, Pa 2 and Pa 4).<br><br>CONCLUSION: When exposed to low ZnO NPs concentrations, P. aeruginosa behaves in a hormetic manner, undergoing positive growth and biofilm formation. These results highlight the importance of understanding the response of P. aeruginosa following exposure to low ZnO NPs concentrations.}, }
@article {pmid39094962, year = {2024}, author = {Huang, X and Wu, M and Chen, Y and Feng, L and Ji, F and Li, L and Huang, L and Wang, Y and Shen, F and Deng, S and Fang, D}, title = {Ultrahigh carbon utilization in symbiotic biofilm-sludge denitrification systems using polymers as sole electron donors.}, journal = {Bioresource technology}, volume = {408}, number = {}, pages = {131194}, doi = {10.1016/j.biortech.2024.131194}, pmid = {39094962}, issn = {1873-2976}, mesh = {*Biofilms ; *Carbon ; *Denitrification ; *Sewage/microbiology ; Nitrates/metabolism ; Electrons ; Polyesters/chemistry/metabolism ; Polymers/chemistry ; Symbiosis/physiology ; Water Purification/methods ; Bioreactors ; }, abstract = {The polymer-based denitrification system is an effective nitrate removal process for treating low carbon/nitrogen wastewater. However, in polymer denitrification systems, carbon used for the denitrification reaction is weakly targeted. Improving the efficiency of carbon utilization in denitrification is important to reduce carbon wastage. In this study, a symbiotic biofilm-sludge denitrification system was constructed using polycaprolactone as electron donors. Results show that the carbon release amount in 120 days was 85.32±0.46 g, and the unit mass of polycaprolactone could remove 1.55±0.01 g NO3[-]-N. Meaningfully, the targeted carbon utilization efficiency for denitrification could achieve 79%-85%. The quantitative results showed that the release of electron donors can be well matched to the demand for electron acceptors in the biofilm-sludge denitrification system. Overall, the symbiotic system can improve the nitrate removal efficiency and reduce the waste of carbon source.}, }
@article {pmid39094920, year = {2024}, author = {Yan, C and Nakajima, M and Ikeda-Imafuku, M and Yanagawa, M and Hayatsu, M and Fukuta, T and Shibata, S and Mitragotri, S and Tabeta, K}, title = {Choline and geranate ionic liquid for subgingival biofilm control.}, journal = {International journal of pharmaceutics}, volume = {662}, number = {}, pages = {124544}, doi = {10.1016/j.ijpharm.2024.124544}, pmid = {39094920}, issn = {1873-3476}, mesh = {*Biofilms/drug effects ; *Choline/chemistry ; *Ionic Liquids/chemistry/pharmacology ; *Anti-Bacterial Agents/pharmacology/administration &amp; dosage/chemistry ; Periodontitis/drug therapy/microbiology ; Cell Membrane Permeability/drug effects ; }, abstract = {Periodontitis is a chronic inflammatory disease that causes destruction of the periodontium and eventual tooth loss. The priority in the periodontal treatment is to remove the subgingival biofilm. Chemical removal of biofilms using antimicrobial agents has been applied in clinical practice. However, their clinical effect is still limited because the agents must overcome biofilm's significant drug tolerance, which is primarily caused by the extracellular matrix, a physical barrier that attenuates drug diffusion. This study aimed to study the use of ionic liquids (ILs), a new class of biocompatible materials, for controlling subgingival biofilms because of their excellent permeability. Choline and geranate (CAGE) IL was tested for its highly potent antiseptic behavior and permeability. Antibacterial tests revealed that the significant efficacy of CAGE against periodontopathic microorganisms was derived from their ability to destroy cell membrane, as demonstrated by membrane permeability assay and transmission electron microscopy imaging. Antibiofilm tests using two pathogenic biofilm models revealed that CAGE exerted efficacy against the biofilm-embedded bacteria, conspicuously neutralized the biofilms, and eventually destroyed the biofilm structure. Furthermore, the penetration of CAGE into the biofilm was visually confirmed using confocal laser scanning microscopy. This study highlighted the potential of CAGE as a powerful antibiofilm therapeutic.}, }
@article {pmid39094711, year = {2024}, author = {Ramírez, N and Cassola, F and Gambero, A and Sartoratto, A and Gómez Castellanos, LM and Ribeiro, G and Ferreira Rodrigues, RA and Duarte, MCT}, title = {Control of pathogenic bacterial biofilm associated with acne and the anti-inflammatory potential of an essential oil blend.}, journal = {Microbial pathogenesis}, volume = {194}, number = {}, pages = {106834}, doi = {10.1016/j.micpath.2024.106834}, pmid = {39094711}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Oils, Volatile/pharmacology ; Humans ; *Acne Vulgaris/microbiology/drug therapy ; Mice ; *Anti-Inflammatory Agents/pharmacology ; *Anti-Bacterial Agents/pharmacology ; *Propionibacterium acnes/drug effects ; *Staphylococcus epidermidis/drug effects ; Animals ; *Staphylococcus aureus/drug effects ; *Keratinocytes/drug effects/microbiology ; *Microbial Sensitivity Tests ; *Macrophages/drug effects/microbiology ; *Tumor Necrosis Factor-alpha/metabolism ; Fibroblasts/drug effects/microbiology ; Cell Survival/drug effects ; HaCaT Cells ; Cell Line ; Plant Oils/pharmacology ; }, abstract = {Acne is one of the most common skin conditions worldwide, with multifactorial origins it affects areas of the skin with hair follicles and sebaceous glands that become clogged. Bacterial incidence aggravates treatment due to resistance to antimicrobial agents and production of virulence factors such as biofilm formation. Based on these information, this study aims to conduct in vitro evaluations of the antibacterial activity of essential oils (EOs), alone and in combination, against Propionibacterium acnes, Staphylococcus aureus, and Staphylococcus epidermidis in planktonic and biofilm forms. This study also assessed the anti-inflammatory potential (TNF-α) and the effects of EOs on the viability of human keratinocytes (HaCaT), murine fibroblasts (3T3-L1), and bone marrow-derived macrophages (BMDMs). Of all EOs tested, 13 had active action against P. acnes, 9 against S. aureus, and 9 against S. epidermidis at concentrations of 0.125-2.0 mg/mL. Among the most active plant species, a blend of essential oil (BEOs) was selected, with Cymbopogon martini (Roxb.) Will. Watson, Eugenia uniflora L., and Varronia curassavica Jacq., the latter due to its anti-inflammatory action. This BEOs showed higher inhibition rates when compared to chloramphenicol against S. aureus and S. epidermidis, and higher eradication rates when compared to chloramphenicol for the three target species. The BEOs did not affect the cell viability of cell lines evaluated, and the levels of TNF-α decreased. According to these results, the BEOs evaluated showed potential for the development of an alternative natural formulation for the treatment of acne.}, }
@article {pmid39093050, year = {2024}, author = {Basotra, SD and Kumari, Y and Vij, M and Tyagi, A and Sharma, D and Bhattacharyya, MS}, title = {ASLdC3: A Derivative of Acidic Sophorolipid Disrupts Mitochondrial Function, Induces ROS Generation, and Inhibits Biofilm Formation in Candida albicans.}, journal = {ACS infectious diseases}, volume = {10}, number = {9}, pages = {3185-3201}, doi = {10.1021/acsinfecdis.4c00155}, pmid = {39093050}, issn = {2373-8227}, mesh = {*Biofilms/drug effects ; *Candida albicans/drug effects/physiology ; *Antifungal Agents/pharmacology/chemistry/chemical synthesis ; *Reactive Oxygen Species/metabolism ; *Mitochondria/drug effects ; *Microbial Sensitivity Tests ; Animals ; Humans ; Oleic Acids ; }, abstract = {Fungal infections account for more than 140 million cases of severe and life-threatening conditions each year, causing approximately 1.7 million deaths annually. Candida albicans and related species are the most common human fungal pathogens, causing both superficial (mucosal and cutaneous) and life-threatening invasive infections (candidemia) with a 40-75% mortality rate. Among many virulence factors of Candida albicans, morphological transition from yeast to hyphae, secretion of hydrolytic enzymes, and formation of biofilms are considered to be crucial for pathogenicity. However, the arsenals for the treatment against these pathogens are restricted to only a few classes of approved drugs, the efficacy of which is being compromised by host toxicity, fungistatic activity, and the emergence of drug resistance. In this study, we have described the development of a molecule, exhibiting excellent antifungal activity (MIC 8 μg/mL), by tailoring acidic sophorolipids with aryl alcohols via enzyme catalysis. This novel derivative, ASLdC3, is a surface-active compound that lowers the surface tension of the air-water interface up to 2-fold before reaching the critical micelle concentration of 25 μg/mL. ASLdC3 exhibits excellent antibiofilm properties against Candida albicans and other nonalbicans Candida species. The molecule primarily exhibits its antifungal activity by perturbing mitochondrial function through the alteration of the mitochondrial membrane potential (MMP) and generation of reactive oxygen species (ROS). The ROS damages fungal cell membrane function and cell wall integrity, eventually leading to cell death. ASLdC3 was found to be nontoxic in in vitro assay and nonhemolytic. Besides, it does not cause toxicity in the C. elegans model. Our study provides a valuable foundation for the potential of acidic sophorolipid as a nontoxic, biodegradable precursor for the design and synthesis of novel molecules for use as antimicrobial drugs as well as for other clinical applications.}, }
@article {pmid39091304, year = {2024}, author = {El-Didamony, SE and Kalaba, MH and Sharaf, MH and El-Fakharany, EM and Osman, A and Sitohy, M and Sitohy, B}, title = {Melittin alcalase-hydrolysate: a novel chemically characterized multifunctional bioagent; antibacterial, anti-biofilm and anticancer.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1419917}, pmid = {39091304}, issn = {1664-302X}, abstract = {The prevalent life-threatening microbial and cancer diseases and lack of effective pharmaceutical therapies created the need for new molecules with antimicrobial and anticancer potential. Bee venom (BV) was collected from honeybee workers, and melittin (NM) was extracted from BV and analyzed by urea-polyacrylamide gel electrophoresis (urea-PAGE). The isolated melittin was hydrolyzed with alcalase into new bioactive peptides and evaluated for their antimicrobial and anticancer activity. Gel filtration chromatography fractionated melittin hydrolysate (HM) into three significant fractions (F1, F2, and F3), that were characterized by electrospray ionization mass spectrometry (ESI-MS) and evaluated for their antimicrobial, anti-biofilm, antitumor, and anti-migration activities. All the tested peptides showed antimicrobial and anti-biofilm activities against Gram-positive and Gram-negative bacteria. Melittin and its fractions significantly inhibited the proliferation of two types of cancer cells (Huh-7 and HCT 116). Yet, melittin and its fractions did not affect the viability of normal human lung Wi-38 cells. The IC50 and selectivity index data evidenced the superiority of melittin peptide fractions over intact melittin. Melittin enzymatic hydrolysate is a promising novel product with high potential as an antibacterial and anticancer agent.}, }
@article {pmid39090348, year = {2024}, author = {Mohan, S and Lavu, V and Ajitkumar, S and Balaji, SK}, title = {Anti-biofilm activity of 445 nm and 970 nm diode laser on mixed species colonies of- aggregatibacter actinomycetemcomitans and porphyromonas gingivalis cultured on titanium discs -an in vitro study.}, journal = {Lasers in medical science}, volume = {39}, number = {1}, pages = {206}, pmid = {39090348}, issn = {1435-604X}, mesh = {*Biofilms/radiation effects/drug effects ; *Porphyromonas gingivalis/physiology ; *Aggregatibacter actinomycetemcomitans ; *Lasers, Semiconductor/therapeutic use ; *Titanium/chemistry ; Humans ; In Vitro Techniques ; }, abstract = {To assess and compare the anti-microbial efficacy of 445 nm and 970 nm diode laser on mixed species biofilm of Aggregatibacter actinomycetemcomitans [A.a] and Porphyromonas gingivalis [P.g] cultured on machined pure titanium discs. A total of 65 machined pure titanium discs with no surface modifications with a 10-mm diameter and a 2-mm height were sterilized by autoclaving at 121 °C for 15 min and incubated with the commercially available bacterial strains ATCC(American Type Culture Collection- P.g 33277 and A.a 29522)mixture of Aggregatibacter actinomycetemcomitans(A.a) and Porphyromonas gingivalis(P.g).After a 2-week incubation period with the mixture of bacteria to develop a mixed species biofilm, the discs were divided into three groups: (1) no treatment (control), (2) 445 nm laser (test), (3) 970 nm laser (test). For each laser wavelength (445 and 970 nm), the discs were exposed to 1.0 W and 2.0 W in continuous wave mode for the times points of 15, 30, and 60 s. The antimicrobial efficacy was assessed by qPCR. A significant reduction in the levels of both species of bacteria was observed between control and the laser intervention groups. A higher efficacy for the 445 nm diode laser against Porphyromonas gingivalis and a similar efficacy against Aggregatibacter actinomycetemcomitans was observed as compared to the 970 nm group. 445 nm wavelength represents a potential and effective laser wavelength which can be used for the management of peri-implant infection. The present study findings also need to be further validated through clinical interventional trials.}, }
@article {pmid39089085, year = {2024}, author = {Oliulla, H and Mizan, MFR and Ashrafudoulla, M and Meghla, NS and Ha, AJ and Park, SH and Ha, SD}, title = {The challenges and prospects of using cold plasma to prevent bacterial contamination and biofilm formation in the meat industry.}, journal = {Meat science}, volume = {217}, number = {}, pages = {109596}, doi = {10.1016/j.meatsci.2024.109596}, pmid = {39089085}, issn = {1873-4138}, mesh = {*Biofilms ; *Plasma Gases/pharmacology ; *Food Microbiology ; Animals ; *Meat/microbiology ; Food Handling/methods ; Bacteria ; Meat Products/microbiology ; Food Contamination/prevention &amp; control ; }, abstract = {The risk of foodborne disease outbreaks increases when the pathogenic bacteria are able to form biofilms, and this presents a major threat to public health. An emerging non-thermal cold plasma (CP) technology has proven a highly effective method for decontaminating meats and their products and extended their shelf life. CP treatments have ability to reduce microbial load and, biofilm formation with minimal change of color, pH value, and lipid oxidation of various meat and meat products. The CP technique offers many advantages over conventional processing techniques due to its layout flexibility, nonthermal behavior, affordability, and ecological sustainability. The technology is still in its infancy, and continuous research efforts are needed to realize its full potential in the meat industry. This review addresses the basic principles and the impact of CP technology on biofilm formation, meat quality (including microbiological, color, pH value, texture, and lipid oxidation), and microbial inactivation pathways and also the prospects of this technology.}, }
@article {pmid39088791, year = {2024}, author = {Rahn, HP and Liu, X and Chosy, MB and Sun, J and Cegelski, L and Wender, PA}, title = {Biguanide-Vancomycin Conjugates are Effective Broad-Spectrum Antibiotics against Actively Growing and Biofilm-Associated Gram-Positive and Gram-Negative ESKAPE Pathogens and Mycobacteria.}, journal = {Journal of the American Chemical Society}, volume = {146}, number = {32}, pages = {22541-22552}, pmid = {39088791}, issn = {1520-5126}, support = {R01 CA031845/CA/NCI NIH HHS/United States ; R01 CA245533/CA/NCI NIH HHS/United States ; R01 GM117278/GM/NIGMS NIH HHS/United States ; R37 CA031845/CA/NCI NIH HHS/United States ; }, mesh = {*Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; *Biofilms/drug effects ; *Vancomycin/pharmacology/chemistry ; *Microbial Sensitivity Tests ; *Gram-Negative Bacteria/drug effects ; *Gram-Positive Bacteria/drug effects ; *Biguanides/pharmacology/chemistry/chemical synthesis ; Mycobacterium/drug effects ; Molecular Structure ; }, abstract = {Strategies to increase the efficacy and/or expand the spectrum of activity of existing antibiotics provide a potentially fast path to clinically address the growing crisis of antibiotic-resistant infections. Here, we report the synthesis, antibacterial efficacy, and mechanistic activity of an unprecedented class of biguanide-antibiotic conjugates. Our lead biguanide-vancomycin conjugate, V-C6-Bg-PhCl (5e), induces highly effective cell killing with up to a 2 orders-of-magnitude improvement over its parent compound, vancomycin (V), against vancomycin-resistant enterococcus. V-C6-Bg-PhCl (5e) also exhibits improved activity against mycobacteria and each of the ESKAPE pathogens, including the Gram-negative organisms. Furthermore, we uncover broad-spectrum killing activity against biofilm-associated Gram-positive and Gram-negative bacteria as well as mycobacteria not observed for clinically used antibiotics such as oritavancin. Mode-of-action studies reveal that vancomycin-like cell wall synthesis inhibition with improved efficacy attributed to enhanced engagement at vancomycin binding sites through biguanide association with relevant cell-surface anions for Gram-positive and Gram-negative bacteria. Due to its potency, remarkably broad activity, and lack of acute mammalian cell toxicity, V-C6-Bg-PhCl (5e) is a promising candidate for treating antibiotic-resistant infections and notoriously difficult-to-treat slowly growing and antibiotic-tolerant bacteria associated with chronic and often incurable infections. More generally, this study offers a new strategy (biguanidinylation) to enhance antibiotic activity and facilitate clinical entry.}, }
@article {pmid39088248, year = {2024}, author = {Walsh, D and Parmenter, C and Bakker, SE and Lithgow, T and Traven, A and Harrison, F}, title = {A new model of endotracheal tube biofilm identifies combinations of matrix-degrading enzymes and antimicrobials able to eradicate biofilms of pathogens that cause ventilator-associated pneumonia.}, journal = {Microbiology (Reading, England)}, volume = {170}, number = {8}, pages = {}, pmid = {39088248}, issn = {1465-2080}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Pneumonia, Ventilator-Associated/microbiology/drug therapy ; *Pseudomonas aeruginosa/drug effects/physiology ; Humans ; *Candida albicans/drug effects/physiology ; *Klebsiella pneumoniae/drug effects/physiology/growth &amp; development ; Intubation, Intratracheal ; Anti-Infective Agents/pharmacology ; Anti-Bacterial Agents/pharmacology ; }, abstract = {Ventilator-associated pneumonia is defined as pneumonia that develops in a patient who has been on mechanical ventilation for more than 48 hours through an endotracheal tube. It is caused by biofilm formation on the indwelling tube, which introduces pathogenic microbes such as Pseudomonas aeruginosa, Klebsiella pneumoniae and Candida albicans into the patient's lower airways. Currently, there is a lack of accurate in vitro models of ventilator-associated pneumonia development. This greatly limits our understanding of how the in-host environment alters pathogen physiology and the efficacy of ventilator-associated pneumonia prevention or treatment strategies. Here, we showcase a reproducible model that simulates the biofilm formation of these pathogens in a host-mimicking environment and demonstrate that the biofilm matrix produced differs from that observed in standard laboratory growth medium. In our model, pathogens are grown on endotracheal tube segments in the presence of a novel synthetic ventilated airway mucus medium that simulates the in-host environment. Matrix-degrading enzymes and cryo-scanning electron microscopy were employed to characterize the system in terms of biofilm matrix composition and structure, as compared to standard laboratory growth medium. As seen in patients, the biofilms of ventilator-associated pneumonia pathogens in our model either required very high concentrations of antimicrobials for eradication or could not be eradicated. However, combining matrix-degrading enzymes with antimicrobials greatly improved the biofilm eradication of all pathogens. Our in vitro endotracheal tube model informs on fundamental microbiology in the ventilator-associated pneumonia context and has broad applicability as a screening platform for antibiofilm measures including the use of matrix-degrading enzymes as antimicrobial adjuvants.}, }
@article {pmid39087223, year = {2024}, author = {Nam, OH and Park, TY and Jeong, SR and Shin, J and Jih, MK}, title = {Antimicrobial effect of two fluoride-releasing adhesive tapes on Streptococcus mutans biofilm.}, journal = {The Journal of clinical pediatric dentistry}, volume = {48}, number = {4}, pages = {132-138}, doi = {10.22514/jocpd.2024.086}, pmid = {39087223}, issn = {1557-5268}, mesh = {*Streptococcus mutans/drug effects ; *Biofilms/drug effects ; *Fluorides/pharmacology/chemistry ; Polyvinyl Alcohol/chemistry/pharmacology ; Microscopy, Confocal ; Microscopy, Electron, Scanning ; Humans ; Cariostatic Agents/pharmacology/chemistry ; Anti-Infective Agents/pharmacology ; }, abstract = {Fluoride-releasing adhesive tapes have been developed as a new fluoride delivery agent. However, application as caries prevention agents remains underexplored. This study aimed at evaluating the antimicrobial activity of two fluoride-releasing adhesive tapes against S. mutans biofilm. Two polyvinyl alcohol (PVA) tapes were investigated: (i) a fluoride-PVA (F-PVA) tape, (ii) a pullulan incorporated F-PVA (PF-PVA) tape. S. mutan strains were cultured and treated with the tapes. Antimicrobial effects were evaluated using the agar diffusion test, field-emission scanning electron microscopy (FE-SEM), and confocal laser scanning microscopy (CLSM). F-PVA tapes showed higher inhibition-zone diameters than PF-PVA at 48 h and 72 h. However, there were no significant differences (p > 0.05) between the effects of F-PVA and PF-PVA. The bio-volume of S. mutans and extracellular polymeric substances significantly decreased in the F-PVA tapes than in the PF-PVA tapes (p < 0.05). FE-SEM micrographs revealed less S. mutans colonization in F-PVA. F-PVA exhibited better antimicrobial activity against S. mutans than PF-PVA.}, }
@article {pmid39086984, year = {2024}, author = {Ullah, N and Hasnain, SZU and Baloch, R and Amin, A and Nasibova, A and Selakovic, D and Rosic, GL and Islamov, S and Naraliyeva, N and Jaradat, N and Mammadova, AO}, title = {Exploring essential oil-based bio-composites: molecular docking and in vitro analysis for oral bacterial biofilm inhibition.}, journal = {Frontiers in chemistry}, volume = {12}, number = {}, pages = {1383620}, pmid = {39086984}, issn = {2296-2646}, abstract = {Oral bacterial biofilms are the main reason for the progression of resistance to antimicrobial agents that may lead to severe conditions, including periodontitis and gingivitis. Essential oil-based nanocomposites can be a promising treatment option. We investigated cardamom, cinnamon, and clove essential oils for their potential in the treatment of oral bacterial infections using in vitro and computational tools. A detailed analysis of the drug-likeness and physicochemical properties of all constituents was performed. Molecular docking studies revealed that the binding free energy of a Carbopol 940 and eugenol complex was -2.0 kcal/mol, of a Carbopol 940-anisaldehyde complex was -1.9 kcal/mol, and a Carbapol 940-eugenol-anisaldehyde complex was -3.4 kcal/mol. Molecular docking was performed against transcriptional regulator genes 2XCT, 1JIJ, 2Q0P, 4M81, and 3QPI. Eugenol cinnamaldehyde and cineol presented strong interaction with targets. The essential oils were analyzed against Staphylococcus aureus and Staphylococcus epidermidis isolated from the oral cavity of diabetic patients. The cinnamon and clove essential oil combination presented significant minimum inhibitory concentrations (MICs) (0.0625/0.0312 mg/mL) against S. epidermidis and S. aureus (0.0156/0.0078 mg/mL). In the anti-quorum sensing activity, the cinnamon and clove oil combination presented moderate inhibition (8 mm) against Chromobacterium voilaceum with substantial violacein inhibition (58% ± 1.2%). Likewise, a significant biofilm inhibition was recorded in the case of S. aureus (82.1% ± 0.21%) and S. epidermidis (84.2% ± 1.3%) in combination. It was concluded that a clove and cinnamon essential oil-based formulation could be employed to prepare a stable nanocomposite, and Carbapol 940 could be used as a compatible biopolymer.}, }
@article {pmid39086652, year = {2024}, author = {Das, S and Kaledhonkar, S}, title = {Physiochemical characterization of a potential Klebsiella phage MKP-1 and analysis of its application in reducing biofilm formation.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1397447}, pmid = {39086652}, issn = {1664-302X}, abstract = {The common intestinal pathogen Klebsiella pneumoniae (K. pneumoniae) is one of the leading causes of fatal superbug infections that can resist the effects of commonly prescribed medicines. The uncontrolled use or misuse of antibiotics has increased the prevalence of drug-resistant K. pneumoniae strains in the environment. In the quest to search for alternative therapeutics for treating these drug-resistant infections, bacteriophages (bacterial viruses) emerged as potential candidates for in phage therapy against Klebsiella. The effective formulation of phage therapy against drug-resistant Klebsiella infections demands thorough characterization and screening of many bacteriophages. To contribute effectively to the formulation of successful phage therapy against superbug infections by K. pneumoniae, this study includes the isolation and characterization of a novel lytic bacteriophage MKP-1 to consider its potential to be used as therapeutics in treating drug-resistant Klebsiella infections. Morphologically, having a capsid attached to a long non-contractile tail, it was found to be a siphovirus that belongs to the class Caudoviricetes and showed infectivity against different strains of the target host bacterium. Comparatively, this double-stranded DNA phage has a large burst size and is quite stable in various physiological conditions. More interestingly, it has the potential to degrade the tough biofilms formed by K. pneumoniae (Klebsiella pneumoniae subsp. pneumoniae (Schroeter) Trevisan [ATCC 15380]) significantly. Thus, the following study would contribute effectively to considering phage MKP-1 as a potential candidate for phage therapy against Klebsiella infection.}, }
@article {pmid39085984, year = {2024}, author = {Aktekin, MB and Oksuz, Z and Turkmenoglu, B and Istifli, ES and Kuzucu, M and Algul, O}, title = {Synthesis and evaluation of di-heterocyclic benzazole compounds as potential antibacterial and anti-biofilm agents against Staphylococcus aureus.}, journal = {Chemical biology &amp; drug design}, volume = {104}, number = {2}, pages = {e14601}, doi = {10.1111/cbdd.14601}, pmid = {39085984}, issn = {1747-0285}, support = {2021-1-TP3-4120//Mersin University/ ; }, mesh = {*Biofilms/drug effects ; *Staphylococcus aureus/drug effects ; *Anti-Bacterial Agents/pharmacology/chemical synthesis/chemistry ; *Microbial Sensitivity Tests ; *Molecular Docking Simulation ; *DNA Gyrase/metabolism ; Humans ; Heterocyclic Compounds/chemistry/pharmacology/chemical synthesis ; Structure-Activity Relationship ; Cell Line ; Catalytic Domain ; }, abstract = {Cumulative escalation in antibiotic-resistant pathogens necessitates the quest for novel antimicrobial agents, as current options continue to diminish bacterial resistance. Herein, we report the synthesis of di-heterocyclic benzazole structures (12-19) and their in vitro evaluation for some biological activities. Compounds 16 and 17 demonstrated potent antibacterial activity (MIC = 7.81 μg/mL) against Staphylococcus aureus, along with significant anti-biofilm activity. Noteworthy is the capability of Compound 17 to inhibit biofilm formation by at least 50% at sub-MIC (3.90 μg/mL) concentration. Furthermore, both compounds exhibited the potential to inhibit preformed biofilm by at least 50% at the MIC concentration (7.81 μg/mL). Additionally, Compounds 16 and 17 were examined for cytotoxic effects in HFF-1 cells, using the MTT method, and screened for binding interactions within the active site of S. aureus DNA gyrase using in silico molecular docking technique, employing AutoDock 4.2.6 and Schrödinger Glidse programs. Overall, our findings highlight Compounds 16 and 17 as promising scaffolds warranting further optimization for the development of effective antibacterial and anti-biofilm agents.}, }
@article {pmid39084967, year = {2024}, author = {Zang, K and Sun, Y and Jiang, Y and Liu, M and Sun, J and Li, H and Zheng, F and Sun, B}, title = {Preparation and characterization of Baijiu Jiuzao cellulose nanofibers-kafirin composite bio-film with excellent physical properties.}, journal = {International journal of biological macromolecules}, volume = {275}, number = {Pt 1}, pages = {133993}, doi = {10.1016/j.ijbiomac.2024.133993}, pmid = {39084967}, issn = {1879-0003}, mesh = {*Cellulose/chemistry ; *Nanofibers/chemistry ; Tensile Strength ; }, abstract = {Jiuzao is the main solid by-products of Baijiu industry, which contain a high amount of underutilized cellulose and proteins. In recent years, cellulose nanofibers mixed with proteins to prepare biodegradable bio-based film materials have received widespread attention. In this study, we propose a novel method to simultaneously extract kafirin and cellulose from strong-flavor type of Jiuzao, and modify cellulose to prepare cellulose nanofibers by the TEMPO (2,2,6,6-tetramethylpiperidine-1-oxide) oxidation-pressure homogenization technique, and finally mix kafirin with cellulose nanofibers to prepare a new biodegradable bio-based composite film. Based on the analysis of one-way and response surface experiments, the highest purity of cellulose was 82.04 %. During cellulose oxidation, when NaClO was added at 25 mmol/g, cellulose nanofibers have a particle size of 80-120 nm, a crystallinity of 65.8°. Finally, kafirin and cellulose nanofibers were mixed to prepare films. The results showed that when cellulose nanofibers were added at 1 %, the film surface was smooth, the light transmittance was 60.8 %, and the tensile strength was 9.17 MPa at maximum, which was 104 % higher than pure protein film. The contact angle was 34.3°. This paper provides new ideas and theoretical basis for preparing biodegradable bio-based composite film materials, and improves the added value of Jiuzao.}, }
@article {pmid39084546, year = {2024}, author = {Teulé-Trull, M and Demiquels-Punzano, E and Pérez, RA and Aparicio, C and Durán-Sindreu, F and Sánchez-López, E and González-Sánchez, JA and Delgado, LM}, title = {Revision of ex vivo endodontic biofilm model using computer aided design.}, journal = {Journal of dentistry}, volume = {149}, number = {}, pages = {105270}, doi = {10.1016/j.jdent.2024.105270}, pmid = {39084546}, issn = {1879-176X}, mesh = {*Biofilms/drug effects ; Humans ; *Enterococcus faecalis/drug effects ; *Computer-Aided Design ; Anti-Bacterial Agents/pharmacology/therapeutic use ; Printing, Three-Dimensional ; Microscopy, Confocal ; Dental Pulp Cavity/microbiology ; Dental Pulp/microbiology ; }, abstract = {OBJECTIVE: Most endodontic diseases are bacterium-mediated inflammatory or necrotic process induced by contaminated dental pulp. Although great advances are being performed to obtain more efficient antibacterial strategies for persistent infections, most studies lack of representative models to test their antibacterial effects and their outcomes cannot be promptly translated to clinical practice. Therefore, this study aimed to refine an ex vivo endodontic biofilm model combining human tooth, computer guided design and 3D printing to obtain a more reproducible and predictable model.<br><br>METHODS: Monoradicular teeth were cut using three different methods: hand-held (HCC), mechanical precision (MPC) and computer aid guided cutting (CGC). Then, blocks were reassembled. The different model preparations were assessed in terms of dimensional tolerance, surface analysis, liquid tightness and Enterococcus faecalis biofilm development for 21 days, which was studied by metabolic assays and confocal microscopy. Then, the proposed model was validated using different commercial disinfecting treatments.<br><br>RESULTS: CGC exhibited significantly lower deviation and surface without defects compared to HHC and MPC, leading to superior liquid tightness. Similarly, mature biofilms with high metabolic activity and vitality were observed in all conditions, CGC showing the lowest variation. Regarding the model validation, all antibacterial treatments resulted in the complete eradication of bacteria in the standard 2D model, whereas commercial treatments exhibited varying levels of efficacy in the proposed ex vivo model, from moderately reduction of metabolic activity to complete elimination of biofilm.<br><br>CONCLUSIONS: The novel guided approach represents a more reliable, standardized, and reproducible model for the evaluation of endodontic disinfecting therapies.<br><br>CLINICAL SIGNIFICANCE: During antibacterial treatment development, challenging 3D models using teeth substrates to test antibacterial treatments novel guided approach represents a more reliable, standardized, and reproducible model for the evaluation of endodontic disinfecting therapies.}, }
@article {pmid39084089, year = {2024}, author = {Tang, B and Hung, W and Salam, M and Zhang, L and Yang, Y and Niu, J and Li, H and Zhang, L}, title = {Suspended particulate matter-biofilm aggregates benefit microcystin removal in turbulent water but trigger toxicity toward Daphnia magna.}, journal = {Water research}, volume = {263}, number = {}, pages = {122150}, doi = {10.1016/j.watres.2024.122150}, pmid = {39084089}, issn = {1879-2448}, mesh = {*Daphnia/drug effects ; *Microcystins/toxicity ; Animals ; *Biofilms/drug effects ; Particulate Matter/toxicity ; Marine Toxins ; Water Pollutants, Chemical/toxicity ; Adsorption ; Daphnia magna ; }, abstract = {Suspended particulate matter (SPM) and biofilm are critical in removing contaminants in aquatic environments, but the environmental behavior and ecological toxicity of SPM-biofilm aggregates modulated by turbulence intensities are largely unknown. This study determined the removal pathways of microcystin-LR (MC-LR) by SPM and its biofilm under different turbulence intensities (2.25 × 10[-3], 1.01 × 10[-2], and 1.80 × 10[-2] m[2]/s[3]). Then, we evaluated the toxicity of SPM-biofilm aggregates to Daphnia magna. The results revealed that SPM contributed to the adsorption of MC-LR, and the removal of MC-LR can be accelerated with biofilm formation on SPM, with 95.66 % to 97.45 % reduction in MC-LR concentration under the studied turbulence intensities. Higher turbulence intensity triggered more frequent contact of SPM and MC-LR, formed compact but smaller clusters of SPM-biofilm aggregates, and enhanced the abundance of mlrA and mlrB; thus benefiting the adsorption, biosorption, and biodegradation of MC-LR. Furthermore, the SPM-biofilm aggregates formed in turbulent water triggered oxidative stress to Daphnia magna, while a weak lethal toxic effect was identified under moderate turbulence intensity. The results indicate that the toxicity of SPM-biofilm aggregates fail to display a linear relationship with turbulence intensity. These findings offer new perspectives on understanding the environmental behavior and ecological outcomes of SPM and its biofilms in turbulent aquatic environments.}, }
@article {pmid39079336, year = {2024}, author = {Zhang, Y and Li, X and Ren, A and Yao, M and Chen, C and Zhang, H and van der Meer, W and Liu, G}, title = {Impacts of water treatments on bacterial communities of biofilm and loose deposits in drinking water distribution systems.}, journal = {Environment international}, volume = {190}, number = {}, pages = {108893}, doi = {10.1016/j.envint.2024.108893}, pmid = {39079336}, issn = {1873-6750}, mesh = {*Biofilms/growth &amp; development/drug effects ; *Drinking Water/microbiology ; *Water Purification/methods ; *Water Supply ; *Bacteria ; Water Microbiology ; }, abstract = {Treated drinking water is delivered to customers through drinking water distribution systems (DWDSs). Although studies have focused on exploring the microbial ecology of DWDSs, knowledge about the effects of different water treatments on the bacterial community of biofilm and loose deposits in DWDS is limited. This study assessed the effects of additional treatments on the bacterial communities developed in 10 months' old pilot DWDSs. The results showed a similar bacterial community in the pipe-wall biofilm, which was dominated by Novosphingobium spp. (20-82 %) and Sphingomonas spp. (11-53 %), regardless of the treatment applied. The bacterial communities that were retained in the distribution systems (including pipe-wall biofilm and loose deposits) were similar to the particle-associated bacteria (PAB) in the corresponding supply water. The additional treatments showed clear effects of the removal and/or introduction of particles. The genera Aeromonas spp., Clostridium spp., Legionella spp., and Pseudomonas spp., which contain opportunistic pathogenic species, were only detected among the PAB in ion exchange system. Our study demonstrated that the biofilm community is consistent across treatments, and the contribution from bacteria in loose deposits is important but can be controlled by removing particles. These findings offer more insight into the origin and development of microbial ecology in DWDSs and suggest paths for further research on the possibility of managing the microbial ecology in distribution systems.}, }
@article {pmid39079293, year = {2024}, author = {Li, T and Li, CY and Wang, YF and Zhang, JN and Li, H and Wu, HF and Yang, XL and Song, HL}, title = {Insights to the cooperation of double-working potential electroactive biofilm for performance of sulfamethoxazole removal: ARG fate and microorganism communities.}, journal = {Journal of hazardous materials}, volume = {477}, number = {}, pages = {135357}, doi = {10.1016/j.jhazmat.2024.135357}, pmid = {39079293}, issn = {1873-3336}, mesh = {*Biofilms/drug effects ; *Sulfamethoxazole ; Water Pollutants, Chemical/chemistry/metabolism ; Anti-Bacterial Agents/chemistry ; Drug Resistance, Microbial/genetics ; Electrochemical Techniques ; Bacteria/metabolism/genetics/drug effects ; Genes, Bacterial ; }, abstract = {Bioelectrochemical systems (BESs) have shown great potential in enhancing sulfamethoxazole (SMX) removal. However, electroactive biofilms (EBs) constructed with single potentials struggle due to limited biocatalytic activity, hindering deep SMX degradation. Here, we constructed a double-working potential BES (BES-D) to investigate its ability to eliminate SMX and reduce the levels of corresponding antibiotic resistance genes (ARGs). The preferable electrochemical activity of EB in BES-D was confirmed by electrochemical characterization, EPS analysis, physical structure, viability of the biofilm, and cytochrome content. BES-D exhibited a notably greater SMX removal efficiency (94.2 %) than did the single-working potential BES (BES-S) and the open-circuit group (OC). Degradation pathway analysis revealed that the cooperative EB could accelerate the in-depth removal of SMX. Moreover, EB interaction in BES-D decreased the relative abundance of ARGs in biofilms compared to that in BES-S, although the absolute number of ARG copies increased in BES-D effluents. Compared to those in BES-S and OC, more complex cross-niche microbial associations in the EB of BES-D were observed by network analysis of the bacterial community and ARG hosts, enhancing the degradation efficiency of SMX. In conclusion, BES-D has significant potential for SMX removal and the enhancement of EB activity. Nonetheless, the risk of ARG dissemination in effluent remains a concern.}, }
@article {pmid39079190, year = {2024}, author = {Müderris, T and Dursun Manyaslı, G and Kaya, S and Gül Yurtsever, S}, title = {In vitro interactions of combinations of colistin with meropenem, rifampicin and tigecycline in colistin-resistant, biofilm-forming Klebsiella pneumoniae.}, journal = {Diagnostic microbiology and infectious disease}, volume = {110}, number = {2}, pages = {116408}, doi = {10.1016/j.diagmicrobio.2024.116408}, pmid = {39079190}, issn = {1879-0070}, mesh = {*Klebsiella pneumoniae/drug effects ; *Biofilms/drug effects ; *Colistin/pharmacology ; *Tigecycline/pharmacology ; *Rifampin/pharmacology ; *Meropenem/pharmacology ; *Anti-Bacterial Agents/pharmacology ; Humans ; *Microbial Sensitivity Tests ; *Drug Synergism ; *Klebsiella Infections/microbiology/drug therapy ; Drug Resistance, Bacterial ; }, abstract = {In this study, it was aimed to reveal the in vitro interactions of combinations of colistin with meropenem, rifampicin and tigecycline in colistin-resistant, biofilm-forming Klebsiella pneumonia. A total of 30 isolates, 15 of which formed biofilms and 15 did not form biofilms, were randomly selected from K. pneumoniae isolates growing in blood samples. The synergy rates of colistin-meropenem, colistin-tigecycline, colistin-rifampicin combinations in planktonic/sessile bacteria are; It was determined as 83,3%/73,3%, 66,6%/33,3%, 100%/60% respectively. Biofilm inhibitory concentration (BIC) of colistin, meropenem, tigecycline, and rifampicin significantly increased after biofilm formation. The synergistic activity seen in the sessile form was independent of the planktonic form. Although a high synergistic effect was observed in the meropenem-colistin combination on sessile bacteria, colistin had very high BIC in all combinations. Large-scale studies are needed in which the number of isolates studied is large, bacterial resistance profiles are evaluated genomically, and various antimicrobial groups are included.}, }
@article {pmid39077794, year = {2024}, author = {Guedes, GMM and Ocadaque, CJ and Amando, BR and Freitas, AS and Pereira, VC and Cordeiro, RA and Bandeira, SP and Souza, PFN and Rocha, MFG and Sidrim, JJC and Souza Collares Maia Castelo-Branco, D}, title = {Influence of carbonyl cyanide m-chlorophenyl hydrazone on biofilm dynamics, protease, and siderophore production by Burkholderia pseudomallei.}, journal = {Biofouling}, volume = {40}, number = {8}, pages = {514-526}, doi = {10.1080/08927014.2024.2385038}, pmid = {39077794}, issn = {1029-2454}, mesh = {*Biofilms/drug effects ; *Siderophores/pharmacology ; *Burkholderia pseudomallei/drug effects/physiology ; *Anti-Bacterial Agents/pharmacology ; *Carbonyl Cyanide m-Chlorophenyl Hydrazone/pharmacology ; *Microbial Sensitivity Tests ; *Peptide Hydrolases/metabolism ; Virulence Factors ; }, abstract = {Efflux pump inhibitors are a potential therapeutic strategy for managing antimicrobial resistance and biofilm formation. This article evaluated the effect of carbonyl cyanide m-chlorophenyl hydrazone (CCCP) on the biofilm growth dynamics and the production of virulence factors by Burkholderia pseudomallei. The effects of CCCP on planktonic, growing, and mature biofilm, interaction with antibacterial drugs, and protease and siderophore production were assessed. CCCP MICs ranged between 128 and 256 µM. The CCCP (128 µM) had a synergic effect with all the antibiotics tested against biofilms. Additionally, CCCP reduced (p < .05) the biomass of biofilm growth and mature biofilms at 128 and 512 µM, respectively. CCCP also decreased (p < .05) protease production by growing (128 µM) and induced (p < .05) siderophore release by planktonic cells (128 µM) growing biofilms (12.8 and 128 µM) and mature biofilms (512 µM). CCCP demonstrates potential as a therapeutic adjuvant for disassembling B. pseudomallei biofilms and enhancing drug penetration.}, }
@article {pmid39075606, year = {2024}, author = {Zhang, T and Ji, S and Zhang, M and Wu, F and Li, X and Luo, X and Huang, Q and Li, M and Zhang, Y and Lu, R}, title = {Effect of capsular polysaccharide phase variation on biofilm formation, motility and gene expression in Vibrio vulnificus.}, journal = {Gut pathogens}, volume = {16}, number = {1}, pages = {40}, pmid = {39075606}, issn = {1757-4749}, support = {QN2022044//Research Projects of Nantong Health Commission/ ; MS12021045//Research Projects of Nantong Health Commission/ ; MA2020018//Subject of Nantong Science and Technology Bureau/ ; }, abstract = {Vibrio vulnificus, a significant marine pathogen, undergoes opaque (Op)-translucent (Tr) colony switching based on whether capsular polysaccharide (CPS) is produced. CPS phase variation is sometime accompanied by genetic variation or down-regulation of particular genes, such as wzb. In addition, CPS prevents biofilm formation and is important to the virulence of V. vulnificus. However, the extent to which there is a difference in gene expression between Tr and Op colonies and the impact of CPS phase variation on other behaviors of V. vulnificus remain unknown. In this work, the data have shown that CPS phase variation of V. vulnificus is affected by incubation time. Tr and Op strains exhibited similar growth rates. However, Tr strains had enhanced biofilm formation capacities but reduced swimming motility compared to Op strains. The RNA-seq assay revealed 488 differentially expressed genes, with 214 downregulated and 274 upregulated genes, between Tr and Op colonies. Genes associated with Tad pili and CPS were downregulated, whereas those involved in flagellum were upregulated, in Tr colonies compared with Op colonies. In addition, 9 putative c-di-GMP metabolism-associated genes and 28 genes encoding putative regulators were significantly differentially expressed, suggesting that CPS phase variation is probably strictly regulated in V. vulnificus. Moreover, 8 genes encoding putative porins were also differentially expressed between the two phenotypic colonies, indicating that bacterial outer membrane was remodeled during CPS phase variation. In brief, this work highlighted the gene expression profiles associated with CPS phase variation, but more studies should be performed to disclose the intrinsic mechanisms in the future.}, }
@article {pmid39074665, year = {2024}, author = {Yuan, Q and Lou, Y and Chen, S and Chen, Y and Li, X and Zhang, X and Qian, L and Zhang, Y and Sun, Y}, title = {Effect of long-term dosage of hydrazine on mainstream anammox process: Biofilm characteristics and microbial community.}, journal = {Chemosphere}, volume = {363}, number = {}, pages = {142968}, doi = {10.1016/j.chemosphere.2024.142968}, pmid = {39074665}, issn = {1879-1298}, mesh = {*Biofilms/drug effects ; *Bioreactors/microbiology ; *Hydrazines/pharmacology/chemistry ; *Wastewater/chemistry ; *Oxidation-Reduction ; *Waste Disposal, Fluid/methods ; Bacteria/drug effects/metabolism ; Anaerobiosis ; Ammonium Compounds/chemistry ; Nitrogen ; Microbiota/drug effects ; Biomass ; }, abstract = {The impact of the long-term trace hydrazine (N2H4) exogenous supplementation on activity of the anaerobic ammonium oxidation (anammox) biofilm was investigated in a moving bed biofilm reactor (MBBR) for mainstream wastewater treatment. The results of this study demonstrated that the addition of 2-5 mg/L N2H4 enhanced anammox biofilm activity, as evidenced by the augmented nitrogen removal rate (NRR), which increased from 113.4 g/(m[3]·d) to 126.7 g/(m[3]·d) with the introduction of 2 mg/L N2H4. However, a higher concentration of N2H4 (10 mg/L) suppressed anammox activity, leading to a reduced NRR of 91.5 g/(m[3]·d). Bioindicators revealed that the long-term addition of 2 mg/L N2H4 fostered the accumulation of anammox bacteria (AnAOB) biomass, elevating the volatile suspended solids (VSS) content by 12%. Moreover, the structural composition of extracellular polymeric substances (EPS) within the biofilm was altered, resulting in enhanced biofilm strength within the reactor. The protective mechanism of the biofilm was activated, and EPS secretion was stimulated by the continuous N2H4 supplementation. The introduction of an excess dosage of N2H4 led to alterations in the microbial communities, ultimately resulting in a decline in the performance of the reactor. These findings collectively illustrate that N2H4, as an intermediate product, can effectively enhance anammox activity within the MBBR for mainstream wastewater treatment. This study contributes to the understanding of the optimization strategies for anammox processes in wastewater treatment systems.}, }
@article {pmid39073000, year = {2024}, author = {Chen, S and Huang, B and Tian, J and Zhang, W}, title = {Advancements of Porphyrin-Derived Nanomaterials for Antibacterial Photodynamic Therapy and Biofilm Eradication.}, journal = {Advanced healthcare materials}, volume = {13}, number = {27}, pages = {e2401211}, doi = {10.1002/adhm.202401211}, pmid = {39073000}, issn = {2192-2659}, support = {52333014//National Natural Science Foundation of China/ ; 22075079//National Natural Science Foundation of China/ ; 52203009//National Natural Science Foundation of China/ ; }, mesh = {*Biofilms/drug effects ; *Photochemotherapy/methods ; *Porphyrins/chemistry/pharmacology ; *Anti-Bacterial Agents/chemistry/pharmacology ; *Nanostructures/chemistry ; Humans ; Photosensitizing Agents/chemistry/pharmacology ; Animals ; }, abstract = {The threat posed by antibiotic-resistant bacteria and the challenge of biofilm formation has highlighted the inadequacies of conventional antibacterial therapies, leading to increased interest in antibacterial photodynamic therapy (aPDT) in recent years. This approach offers advantages such as minimal invasiveness, low systemic toxicity, and notable effectiveness against drug-resistant bacterial strains. Porphyrins and their derivatives, known for their high molar extinction coefficients and singlet oxygen quantum yields, have emerged as crucial photosensitizers in aPDT. However, their practical application is hindered by challenges such as poor water solubility and aggregation-induced quenching. To address these limitations, extensive research has focused on the development of porphyrin-based nanomaterials for aPDT, enhancing the efficacy of photodynamic sterilization and broadening the range of antimicrobial activity. This review provides an overview of various porphyrin-based nanomaterials utilized in aPDT and biofilm eradication in recent years, including porphyrin-loaded inorganic nanoparticles, porphyrin-based polymer assemblies, supramolecular assemblies, metal-organic frameworks (MOFs), and covalent organic frameworks (COFs). Additionally, insights into the prospects of aPDT is offered, highlighting its potential for practical implementation.}, }
@article {pmid39072629, year = {2024}, author = {Poddar, K and Anand, A}, title = {Growing Mycobacterial Biofilm as a Model to Study Antimicrobial Resistance.}, journal = {Journal of visualized experiments : JoVE}, volume = {}, number = {209}, pages = {}, doi = {10.3791/66607}, pmid = {39072629}, issn = {1940-087X}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Mycobacterium smegmatis/drug effects/physiology ; *Drug Resistance, Bacterial ; Bacteriological Techniques/methods ; }, abstract = {Many bacteria thrive in intricate natural communities, exhibiting key attributes of multicellularity such as communication, cooperation, and competition. The most prevalent manifestation of bacterial multicellular behavior is the formation of biofilms, often linked to pathogenicity. Biofilms offer a haven against antimicrobial agents, fostering the emergence of antimicrobial resistance. The conventional practice of cultivating bacteria in shake flask liquid cultures fails to represent their proper physiological growth in nature, consequently limiting our comprehension of their intricate dynamics. Notably, the metabolic and transcriptional profiles of bacteria residing in biofilms closely resemble those of naturally growing cells. This parallelism underscores the significance of biofilms as an ideal model for foundational and translational research. This article focuses on utilizing Mycobacterium smegmatis as a model organism to illustrate a technique for cultivating pellicle biofilms. The approach is adaptable to various culture volumes, facilitating its implementation for diverse experimental objectives such as antimicrobial studies. Moreover, the method's design enables the qualitative or quantitative evaluation of the biofilm-forming capabilities of different mycobacterial species with minor adjustments.}, }
@article {pmid39071848, year = {2024}, author = {Zhu, Q and Zheng, Y and Zhou, X and Wang, D and Yuan, M and Qian, D and Liang, S and Yu, W and Yang, J and Hou, H and Hu, J}, title = {c-di-GMP and AHL signals-triggered chemical communication under electrical signaling disruption restores Geobacter sulfurreducens biofilm formation.}, journal = {ISME communications}, volume = {4}, number = {1}, pages = {ycae096}, pmid = {39071848}, issn = {2730-6151}, abstract = {Electrogenic biofilms, which have attracted considerable attention in simultaneous wastewater treatment and energy recovery in bioelectrochemical systems, are regulated by chemical communication and potassium channel-mediated electrical signaling. However, how these two communication pathways interact with each other has not been thoroughly investigated. This study first explored the roles of chemical communication, including intracellular bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) and extracellular N-acyl-homoserine lactone (AHL)-mediated quorum sensing, in electrogenic biofilm formation through an integrated analysis of transcriptomics and metabolomics. Electrical signaling disruption inhibited the formation and electroactivity of Geobacter sulfurreducens biofilm, which was mainly ascribed to the reduction in biofilm viability and extracellular protein/polysaccharide ratio. The upregulation of expression levels of genes encoding c-di-GMP and AHL synthesis by transcriptomic analysis, and the increased secretion of N-butanoyl-L-homoserine lactone by metabolomic analysis confirmed the enhancement of chemical communication under electrical signaling disruption, thus indicating a compensatory mechanism among different signaling pathways. Furthermore, protein-protein interaction network showed the convergence of different signaling pathways, with c-di-GMP-related genes acting as central bridges. This study highlights the interaction of different signaling pathways, especially the resilience of c-di-GMP signaling to adverse external stresses, thereby laying the foundation for facilitating electrogenic biofilm formation under adverse conditions in practical applications.}, }
@article {pmid39071379, year = {2024}, author = {Prentice, JA and Kasivisweswaran, S and van de Weerd, R and Bridges, AA}, title = {Biofilm dispersal patterns revealed using far-red fluorogenic probes.}, journal = {bioRxiv : the preprint server for biology}, volume = {}, number = {}, pages = {}, pmid = {39071379}, issn = {2692-8205}, support = {R00 AI158939/AI/NIAID NIH HHS/United States ; }, abstract = {Bacteria frequently colonize niches by forming multicellular communities called biofilms. To explore new territories, cells exit biofilms through an active process called dispersal. Biofilm dispersal is essential for bacteria to spread between infection sites, yet how the process is executed at the single-cell level remains mysterious. Here, we characterize dispersal at unprecedented resolution for the global pathogen Vibrio cholerae. To do so, we first developed a far-red cell-labeling strategy that overcomes pitfalls of fluorescent protein-based approaches. We reveal that dispersal initiates at the biofilm periphery and ~25% of cells never disperse. We define novel micro-scale patterns that occur during dispersal, including biofilm compression and the formation of dynamic channels. These patterns are attenuated in mutants that reduce overall dispersal or that increase dispersal at the cost of homogenizing local mechanical properties. Collectively, our findings provide fundamental insights into the mechanisms of biofilm dispersal, advancing our understanding of how pathogens disseminate.}, }
@article {pmid39071348, year = {2024}, author = {Bottura, B and McConnell, G and Florek, LC and Smiley, MK and Martin, R and Eana, A and Dayton, HT and Eckartt, KN and Price-Whelan, AM and Hoskisson, PA and Dietrich, LEP and Rooney, LM}, title = {Oxygen Microenvironments in E. coli Biofilm Nutrient Transport Channels: Insights from Complementary Sensing Approaches.}, journal = {bioRxiv : the preprint server for biology}, volume = {}, number = {}, pages = {}, pmid = {39071348}, issn = {2692-8205}, support = {R01 AI103369/AI/NIAID NIH HHS/United States ; }, abstract = {Chemical gradients and the emergence of distinct microenvironments in biofilms are vital to the stratification, maturation and overall function of microbial communities. These gradients have been well characterised throughout the biofilm mass but the microenvironment of recently discovered nutrient transporting channels in Escherichia coli biofilms remains unexplored. This study employs three different oxygen sensing approaches to provide a robust quantitative overview of the oxygen gradients and microenvironments throughout the biofilm transport channel networks formed by E. coli macrocolony biofilms. Oxygen nanosensing combined with confocal laser scanning microscopy established that the oxygen concentration changes along the length of biofilm transport channels. Electrochemical sensing provided precise quantification of the oxygen profile in the transport channels, showing similar anoxic profiles compared with the adjacent cells. Anoxic biosensing corroborated these approaches, providing an overview of the oxygen utilisation throughout the biomass. The discovery that transport channels maintain oxygen gradients contradicts the previous literature that channels are completely open to the environment along the apical surface of the biofilm. We provide a potential mechanism for the sustenance of channel microenvironments via orthogonal visualisations of biofilm thin sections showing thin layers of actively growing cells. This complete overview of the oxygen environment in biofilm transport channels primes future studies aiming to exploit these emergent structures for new bioremediation approaches.}, }
@article {pmid39071244, year = {2024}, author = {Ballah, FM and Hoque, MN and Islam, MS and Faisal, GM and Rahman, AMT and Khatun, MM and Rahman, M and Hassan, J and Rahman, MT}, title = {Genomic Insights of a Methicillin-Resistant Biofilm-Producing Staphylococcus aureus Strain Isolated From Food Handlers.}, journal = {BioMed research international}, volume = {2024}, number = {}, pages = {5516117}, pmid = {39071244}, issn = {2314-6141}, mesh = {*Biofilms/growth &amp; development/drug effects ; Humans ; *Methicillin-Resistant Staphylococcus aureus/genetics/drug effects/isolation &amp; purification ; *Staphylococcal Infections/microbiology ; Whole Genome Sequencing ; Genomics ; Genome, Bacterial/genetics ; Food Handling ; Anti-Bacterial Agents/pharmacology ; Microbial Sensitivity Tests ; Virulence/genetics ; Virulence Factors/genetics ; Phylogeny ; Drug Resistance, Multiple, Bacterial/genetics ; }, abstract = {Methicillin-resistant Staphylococcus aureus (MRSA) is an important zoonotic pathogen associated with a wide range of infections in humans and animals. Thus, the emergence of MRSA clones poses an important threat to human and animal health. This study is aimed at elucidating the genomics insights of a strong biofilm-producing and multidrug-resistant (MDR) S. aureus MTR_BAU_H1 strain through whole-genome sequencing (WGS). The S. aureus MTR_BAU_H1 strain was isolated from food handlers' hand swabs in Bangladesh and phenotypically assessed for antimicrobial susceptibility and biofilm production assays. The isolate was further undergone to high throughput WGS and analysed using different bioinformatics tools to elucidate the genetic diversity, molecular epidemiology, sequence type (ST), antimicrobial resistance, and virulence gene distribution. Phenotypic analyses revealed that the S. aureus MTR_BAU_H1 strain is a strong biofilm-former and carries both antimicrobial resistance (e.g., methicillin resistance; mecA, beta-lactam resistance; blaZ and tetracycline resistance; tetC) and virulence (e.g., sea, tsst, and PVL) genes. The genome of the S. aureus MTR_BAU_H1 belonged to ST1930 that possessed three plasmid replicons (e.g., rep16, rep7c, and rep19), seven prophages, and two clustered regularly interspaced short palindromic repeat (CRISPR) arrays of varying sizes. Phylogenetic analysis showed a close evolutionary relationship between the MTR_BAU_H1 genome and other MRSA clones of diverse hosts and demographics. The MTR_BAU_H1 genome harbours 42 antimicrobial resistance genes (ARGs), 128 virulence genes, and 273 SEED subsystems coding for the metabolism of amino acids, carbohydrates, proteins, cofactors, vitamins, minerals, and lipids. This is the first-ever WGS-based study of a strong biofilm-producing and MDR S. aureus strain isolated from human hand swabs in Bangladesh that unveils new information on the resistomes (ARGs and correlated mechanisms) and virulence potentials that might be linked to staphylococcal pathogenesis in both humans and animals.}, }
@article {pmid39071174, year = {2024}, author = {Kranjec, C and Mathew, JP and Ovchinnikov, K and Fadayomi, I and Yang, Y and Kjos, M and Li, WW}, title = {A bacteriocin-based coating strategy to prevent vancomycin-resistant Enterococcus faecium biofilm formation on materials of interest for indwelling medical devices.}, journal = {Biofilm}, volume = {8}, number = {}, pages = {100211}, pmid = {39071174}, issn = {2590-2075}, abstract = {The ever-increasing use of exogenous materials as indwelling medical devices in modern medicine offers to pathogens new ways to gain access to human body and begin, in some cases, life threatening infections. Biofouling of such materials with bacteria or fungi is a major concern during surgeries, since this is often associated with biofilm formation and difficult to treat, recalcitrant infections. Intense research efforts have therefore developed several strategies to shield the medical devices' surface from colonization by pathogenic microorganisms. Here, we used dopamine as a coupling agent to coat four different materials of medical interest (plastic polyetheretherketone (PEEK), stainless steel, titanium and silicone catheter) with the bacteriocins, enterocin EJ97-short and the thiopeptide micrococcin P1. Water contact angle measurements and x-ray photoelectron spectroscopy were used to verify the effective coating of the materials. The effect of bacteriocins coated on these materials on the biofilm formation by a vancomycin resistant Enterococcus faecium (VRE) strain was studied by biofilm-oriented antimicrobial test (BOAT) and electron scanning microscopy. The in vitro biocompatibility of bacteriocin-modified biomaterials was tested on cultured human cells. The results demonstrated that the binding of the bacteriocins to the implant surfaces is achieved, and the two bacteriocins in combination could inhibit biofilm formation by E. faecium on all four materials. The modified implant showed no cytotoxicity to the human cells tested. Therefore, surface modification with the two bacteriocins may offer a novel and effective way to prevent biofilm formation on a wide range of implant materials.}, }
@article {pmid39070877, year = {2024}, author = {Rodriguez-Merchan, EC}, title = {Biofilm Related Total Knee Arthroplasty Infection: Prevention, Diagnosis and Treatment.}, journal = {The archives of bone and joint surgery}, volume = {12}, number = {7}, pages = {531-534}, pmid = {39070877}, issn = {2345-4644}, abstract = {Biofilm related implant infection is undoubtedly a relevant challenge in total knee arthroplasty (TKA) with our comprehension steadily progressing and novel management approaches being developed. The aim of this article was to review the most important advances in approaches to combat infections due to biofilm-forming bacteria in TKA. The main conclusions were the following: 1) Fundamental management techniques for infected TKA include open DAIR (debridement, antibiotics, and implant retention), and one and two-stage revision TKA; 2) Continuous local antibiotic perfusion (CLAP) appears to diminish the risk of periprosthetic joint infection (PJI); 3) Restraint of quorum sensing seems to avert PJI after TKA; 4) A recent in vitro study showed promising results in the prevention and management of PJI after TKA using PMMA [poly(methyl methacrylate)] loaded with up to 100 mg of rifampin.}, }
@article {pmid39070325, year = {2024}, author = {Echhpal, UR and Shah, KK and Ahmed, N}, title = {Effectiveness of Denture Cleansers on Candida albicans Biofilm on Conventionally Fabricated, Computer-Aided Design/Computer-Aided Manufacturing-Milled, and Rapid-Prototyped Denture Base Resins: An In Vitro Study.}, journal = {Cureus}, volume = {16}, number = {6}, pages = {e63290}, pmid = {39070325}, issn = {2168-8184}, abstract = {INTRODUCTION: Conventionally fabricated denture base resins have been used for over 150 years. Newer denture base resins can provide a superior fit and may be customized to the patient's characteristics, but the literature on their cleansibility remains limited. The oral cavity can be a hub for thousands of microflora. The maintenance of complete dentures by edentulous patients depends not only on the maintenance of the patient but also on the material used, biofilm adherence, and polishability.<br><br>MATERIALS AND METHODS: Cuboid specimens of 10 &#xd7; 5 &#xd7; 2 mm were designed using the Meshmixer version 3.5 software (Meshmixer, Australia). The standard tessellation (STL) file was imported&#xa0;and sent for printing (NextDent, Netherlands) (Group 1), milling in polymethyl methacrylate (PMMA) (Ivotion, Ivoclar, Schaan, Liechtenstein) (Group 2), and wax milling (Upcera, China), followed by flasking, counter flasking, and packing using heat-cured acrylic resin (DPI, India) (Group 3). The obtained specimens were polished using pumice and sterilized using a UV sterilization unit. The specimens were then immersed in a suspension of candida broth. After three days of biofilm formation, a colony count was performed and noted as colony-forming units per milliliter (CFU/mL). Specimens were treated using Secure denture cleansing tablets (Ghent, New York), table salt (iodized table salt, Tata, India),&#xa0;Clinsodent (ICPA, Mumbai, India), and Polident denture cleansing powder (Polident, Ontario, Canada). A colony count was done after treatment, and the data were tabulated. Statistical analysis was done using SPSS software to compare the efficiency of denture cleansers in all three groups, and statistical significance was set at 0.05. The Kolmogorov-Smirnov test was done to confirm the normality of the data, followed by a one-way analysis of variance (ANOVA) test to compare the efficiency of denture cleansers on the removal of candida colonies.<br><br>RESULTS: Milled denture base resins showed a significantly lower colony count when compared to printed and conventionally fabricated denture base resins. The denture cleansers showed high efficacy in all groups, with the most significant being Secure, which showed a mean difference ranging from 8.114 to 9.887 CFU/mL, followed by Clinsodent,&#xa0;showing a mean of 6.699-9.863 CFU/mL, followed closely by Polident, showing 4.964-7.114 CFU/mL, followed by table salt, being 5.254-8.920 CFU/mL. The 95% confidence interval confirmed statistical significance.<br><br>CONCLUSION: The highest candida colony count was demonstrated by the conventional, followed by rapid prototyping, and was least with milled denture base resins. Following treatment with denture cleansers, Secure demonstrated almost complete eradication of colonies, making it the most effective option. Salt exhibited the lowest efficiency, followed closely by Polident and Clinsodent, and the most effective was Secure denture cleanser.}, }
@article {pmid39069959, year = {2024}, author = {Kathju, A and Nistico, L and Stoodley, P}, title = {Bacterial Biofilm on Tissue Expander and Acellular Dermal Graft After Breast Reconstruction.}, journal = {Surgical infections}, volume = {25}, number = {8}, pages = {632-635}, doi = {10.1089/sur.2024.156}, pmid = {39069959}, issn = {1557-8674}, mesh = {Humans ; Female ; *Acellular Dermis ; *Biofilms ; Adult ; *Mammaplasty/methods ; *Tissue Expansion Devices ; *Staphylococcus aureus ; Staphylococcal Infections/microbiology ; Mastectomy/adverse effects ; Anti-Bacterial Agents/therapeutic use ; Breast Implants/adverse effects/microbiology ; }, abstract = {A 27-year-old female underwent bilateral mastectomy with left axillary dissection and had immediate breast reconstruction with textured silicone implants and acellular dermal graft (ADG) reinforcement of the inferior quadrants. The patient was maintained on oral antibiotics postoperatively and initially did well. However, she subsequently presented with fever, erythema, and tenderness in the left chest and was admitted for intravenous antibiotic therapy. Despite improvement of her symptoms, she ultimately cultured positive for Staphylococcus aureus and had the tissue expander and the ADG material explanted. These explanted specimens were immediately examined with confocal microscopy using Live/Dead staining under hydrated conditions for the presence of bacterial biofilms. Biofilm bacteria were clearly visualized adherent to both the tissue expander shell and also to the ADG surface. This is the first direct demonstration of viable bacteria in biofilm configuration on the surface of a tissue expander and acellular dermal graft after breast reconstruction.}, }
@article {pmid39068786, year = {2024}, author = {Ge, Z and Ai, D and Ma, Z and Li, Y and Zhang, J}, title = {Evolution and distribution of antibiotic resistance genes in submerged macrophytes and biofilm systems: From seasonal monitoring to mesocosm experiments.}, journal = {Journal of environmental management}, volume = {367}, number = {}, pages = {121947}, doi = {10.1016/j.jenvman.2024.121947}, pmid = {39068786}, issn = {1095-8630}, mesh = {*Biofilms ; *Drug Resistance, Microbial/genetics ; Seasons ; Ecosystem ; Proteobacteria/genetics ; Anti-Bacterial Agents/pharmacology ; Bacteria/genetics ; }, abstract = {The aquatic ecosystem has been extensively investigated as a hotspot for the spread of antibiotic resistance genes (ARGs); yet, the evolution and distribution of ARGs profiles in submerged macrophytes biofilms and surrounding water remained unclear. In this study, the dynamic distribution and seasonal variations of microbial communities and ARGs profiles were investigated, alongside their assembly processes and mutual interactions. Bacitracin and multidrug resistance genes were predominant, constituting more than 60% of the total ARGs abundance. The deterministic processes (<65%), influenced by the physicochemical properties of the river environment, governed the assembly and composition of ARGs profiles, exhibiting significant seasonal variation. The peak diversity (21 types) and abundance (0.316 copy ratios) of ARGs were detected during the summer. Proteobacteria and Actinobacteria were the dominant bacterial phyla, accounting for 38.41-85.50% and 4.03-27.09% of the microbial community, respectively. Furthermore, Proteobacteria, especially genera such as Acinetobacter, Burkholderia, and Pseudomonas, with various resistance sequences, were the primary carriers of multiple ARGs. Notably, the genetic exchanges between biofilms and surrounding water facilitated the further propagation of high-risk ARGs, posing greater ecological risks. Redundancy analysis indicated that the total nitrogen and temperature in water determined the fate of pathogenic-resistant species. These findings provided theoretical support for the mitigation of ARGs contamination in aquatic environments.}, }
@article {pmid39068090, year = {2024}, author = {Wu, C and Mangal, U and Seo, JY and Kim, H and Bai, N and Cha, JY and Lee, KJ and Kwon, JS and Choi, SH}, title = {Enhancing biofilm resistance and preserving optical translucency of 3D printed clear aligners through carboxybetaine-copolymer surface treatment.}, journal = {Dental materials : official publication of the Academy of Dental Materials}, volume = {40}, number = {10}, pages = {1575-1583}, doi = {10.1016/j.dental.2024.07.009}, pmid = {39068090}, issn = {1879-0097}, mesh = {*Printing, Three-Dimensional ; *Biofilms/drug effects ; *Surface Properties ; *Materials Testing ; *Methacrylates/chemistry ; Betaine/chemistry/pharmacology/analogs &amp; derivatives ; Microscopy, Electron, Scanning ; Streptococcus mutans/drug effects ; Polymers/chemistry ; Tensile Strength ; Spectroscopy, Fourier Transform Infrared ; }, abstract = {OBJECTIVES: This study aimed to use a carboxybetaine methacrylate (CBMA) copolymer solution to surface treat 3D printed clear aligners at different fabrication stages, to impart antifouling properties, and assess the surface treatment at various fabrication stages' impact on physico-mechanical characteristics.<br><br>METHODS: Surface treatments using a blend of 2-hydroxyethyl methacrylate (HEMA) and CBMA, termed CCS, were performed at various stages of 3D printed clear aligner fabrication. Experimental groups, CB1, CB2, and CB3, were determined by the stage of surface treatment during post-processing. CB1, CB2, and CB3 received treatment before post-curing, after post-curing, and after post-processing, respectively. Untreated samples served as controls. Physical and mechanical properties were assessed through tensile testing, Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and UV-Vis spectroscopy. The surface was further characterized through scanning electron microscopy and contact angle measurements. The cytotoxicity was assessed with 7-day elution and agar diffusion assays. Lastly, bacterial biofilm resistance was evaluated using confocal laser scanning microscopy. Crystal violet assay was performed using Streptococcus mutans.<br><br>RESULTS: Surface treatment during CB1 stage exerted the most significantly unfavorable influence on properties of the 3D printed aligner resin. CB2 samples showed the maximum preservation of translucency even after 7-day aging. CB2 and CB3 phases showed enhanced hydrophilicity of sample surfaces with reduced adhesion of multispecies biofilm and S. mutans.<br><br>SIGNIFICANCE: Application of CCS surface treatment immediately after post-curing (CB2) can enhance the biofilm resistance of 3D printed clear aligners while maintaining high fidelity to optical translucency and constituent mechanical properties.}, }
@article {pmid39067645, year = {2024}, author = {Wan, C and Ju, X and Xu, D and Ou, J and Zhu, M and Lu, G and Li, K and Jiang, W and Li, C and Hu, X and Tian, Y and Niu, Z}, title = {Escherichia coli exopolysaccharides disrupt Pseudomonas aeruginosa biofilm and increase its antibiotic susceptibility.}, journal = {Acta biomaterialia}, volume = {185}, number = {}, pages = {215-225}, doi = {10.1016/j.actbio.2024.07.028}, pmid = {39067645}, issn = {1878-7568}, mesh = {*Biofilms/drug effects ; *Pseudomonas aeruginosa/drug effects/physiology ; *Polysaccharides, Bacterial/pharmacology ; *Anti-Bacterial Agents/pharmacology ; *Escherichia coli/drug effects ; Animals ; Microbial Sensitivity Tests ; Mice ; Tobramycin/pharmacology ; }, abstract = {Pseudomonas aeruginosa (P. aeruginosa) is a major pathogen that causes infectious diseases. It has high tendency to form biofilms, resulting in the failure of traditional antibiotic therapies. Inspired by the phenomenon that co-culture of Escherichia coli (E. coli) and P. aeruginosa leads to a biofilm reduction, we reveal that E. coli exopolysaccharides (EPS) can disrupt P. aeruginosa biofilm and increase its antibiotic susceptibility. The results show that E. coli EPS effectively inhibit biofilm formation and disrupt mature biofilms in P. aeruginosa, Staphylococcus aureus, and E. coli itself. The maximal inhibition and disruption rates against P. aeruginosa biofilm are 40 % and 47 %, respectively. Based on the biofilm-disrupting ability of E. coli EPS, we develop an E. coli EPS/antibiotic combining strategy for the treatment of P. aeruginosa biofilms. The combination with E. coli EPS increases the antibacterial efficiency of tobramycin against P. aeruginosa biofilms in vitro and in vivo. This study provides a promising strategy for treating biofilm infections. STATEMENT OF SIGNIFICANCE: Biofilm formation is a leading cause of chronic infections. It blocks antibiotics, increases antibiotic-tolerance, and aids in immune evasion, thus representing a great challenge in clinic. This study proposes a promising approach to combat pathogenic Pseudomonas aeruginosa (P. aeruginosa) biofilms by combining Escherichia coli exopolysaccharides with antibiotics. This strategy shows high efficiency in different P. aeruginosa stains, including two laboratory strains, PAO1 and ATCC 10145, as well as a clinically acquired carbapenem-resistant strain. In addition, in vivo experiments have shown that this approach is effective against implanted P. aeruginosa biofilms and can prevent systemic inflammation in mice. This strategy offers new possibilities to address the clinical failure of conventional antibiotic therapies for microbial biofilms.}, }
@article {pmid39067337, year = {2024}, author = {Song, W and Ma, R and Liang, Z and Li, J and Dong, J and Du, X and Wang, Z and Li, X}, title = {Biofilm growth characteristic and footprint identification in gravity-driven ceramic membrane bioreactor with electro-coagulation under extreme conditions for roofing rainwater purification.}, journal = {Journal of environmental management}, volume = {367}, number = {}, pages = {121944}, doi = {10.1016/j.jenvman.2024.121944}, pmid = {39067337}, issn = {1095-8630}, mesh = {*Biofilms ; *Bioreactors ; *Ceramics ; Water Purification/methods ; Rain ; Membranes, Artificial ; Phosphorus ; }, abstract = {The identification of biofilm growth footprints influencing on the biofilm detachment and breakup can advance research into how biofilms form. Thus, a gravity-driven ceramic membrane bioreactor (GDCMBR) was used to investigate the growth, detachment and breakup of biofilm using rainwater pretreated by electrocoagulation under 70-days continuous operation. The in-situ ultrasonic time-domain reflectometry (UTDR) technique was applied to non-invasively determine the biofilm thickness. Initially, the biofilm was slowly thickening, but it would collapse and became thinner after accumulating to a certain level, and then it thickened again in a later period, following a cyclic pattern of 'thickening - collapsing - thickening'. This is because the biofilm growth is related with the accumulation of flocs, however, excessive floc formation results in the biofilm being overweight till reaching the thickness limit and thus collapsing. Subsequently, the biofilm gradually thickens again due to the floc production and continuous deposition. Although the biofilm was dynamically changing, the water quality of treatment of the biofilm always remained stable. Ammonia nitrogen and total phosphorus have been almost completely removed, while CODMn removal efficiency was around 25%. And total bacteria amount in the membrane concentrate was obviously higher than that in the influent with the greater microbial activity, demonstrating the remarkable enrichment effect on bacteria. The understanding of biofilm growth characteristic and footprint identification enables us to develop rational approaches to control biofilm structure for efficient GDCMBR performance and operation lifespan.}, }
@article {pmid39066983, year = {2024}, author = {Khan, MAR and Wang, BW and Lin, HC and Yang, YL and Liaw, CC}, title = {Structure-Functional Activity of Pyrone Derivatives for Inhibition of Barnacle Settlement and Biofilm Formation.}, journal = {Marine biotechnology (New York, N.Y.)}, volume = {26}, number = {5}, pages = {1000-1008}, pmid = {39066983}, issn = {1436-2236}, support = {MOST108-2320-B-110-006-MY3//Ministry of Science and Technology grant/ ; NSYSU-KMU 111-I06//National Sun Yat-sen University-Kaohsiung Medical University Joint Research Project/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Thoracica/drug effects ; Animals ; *Pyrones/pharmacology/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; Structure-Activity Relationship ; Biofouling/prevention &amp; control ; Bacteria/drug effects/growth &amp; development ; Microbial Sensitivity Tests ; }, abstract = {Naturally occurring 6-pentyl-2H-pyran-2-one and its synthetic analogues greatly inhibit the settlement of Amphibalanus amphitrite cyprids and the growth and biofilm formation of marine bacteria. To optimize the antifouling activities of pyrone derivatives, this study designed pyrone analogues by modifying functional groups, such as the benzyl group, cyclopentane, and halides, substituted on both sides of a pyrone. The antifouling effects of the synthesized pyrone derivatives were subsequently evaluated against five marine biofilm-forming bacteria, Loktanella hongkongensis, Staphylococcus cohnii, S. saprophyticus, Photobacterium angustum, and Alteromonas macleodii, along with barnacle cyprids of Amphibalanus amphitrite. Substituting nonpolar parts-such as the aliphatic, cyclopentyl, or phenyl moieties on C-5 or the furan moieties on C-3-not only increased antibacterial activity and inhibited biofilm formation but also inhibited barnacle cyprid settlement when compared to 6-pentyl-2H-pyran-2-one.}, }
@article {pmid39066496, year = {2024}, author = {Power, AD and Mok, WWK}, title = {Agar and agarose used for Staphylococcus aureus biofilm cultivation impact fluoroquinolone tolerance.}, journal = {Journal of applied microbiology}, volume = {135}, number = {8}, pages = {}, pmid = {39066496}, issn = {1365-2672}, support = {DP2 GM146456/GM/NIGMS NIH HHS/United States ; DP2GM146456-01/NH/NIH HHS/United States ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Agar ; *Fluoroquinolones/pharmacology ; *Sepharose ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology ; *Staphylococcus aureus/drug effects/physiology/growth &amp; development ; Culture Media/chemistry ; Moxifloxacin/pharmacology ; Methicillin-Resistant Staphylococcus aureus/drug effects/physiology ; }, abstract = {AIMS: Staphylococcus aureus is an opportunistic pathogen whose treatment is further complicated by its ability to form biofilms. In this study, we examine the impact of growing S. aureus biofilms on different polymerizing surfaces, specifically agar and agarose, on the pathogen's tolerance to fluoroquinolones.<br><br>METHODS AND RESULTS: Biofilms of two methicillin-resistant strains of S. aureus were grown on agar or agarose in the presence of the same added nutrients, and their antibiotic susceptibility to two fluoroquinolones, moxifloxacin (MXF) and delafloxacin (DLX), were measured. We also compared the metabolism and extracellular polymeric substances (EPS) production of biofilms that were grown on agar and agarose.<br><br>CONCLUSIONS: Biofilms that were grown on agarose were consistently more susceptible to antibiotics than those grown on agar. We found that in biofilms that were grown on agar, extracellular protein composition was higher, and adding EPS to agarose-grown biofilms increased their tolerance to DLX to levels that were comparable to agar-grown biofilms.}, }
@article {pmid39065765, year = {2024}, author = {Mohammed, EJ and Abdelaziz, AEM and Mekky, AE and Mahmoud, NN and Sharaf, M and Al-Habibi, MM and Khairy, NM and Al-Askar, AA and Youssef, FS and Gaber, MA and Saied, E and AbdElgayed, G and Metwally, SA and Shoun, AA}, title = {Biomedical Promise of Aspergillus Flavus-Biosynthesized Selenium Nanoparticles: A Green Synthesis Approach to Antiviral, Anticancer, Anti-Biofilm, and Antibacterial Applications.}, journal = {Pharmaceuticals (Basel, Switzerland)}, volume = {17}, number = {7}, pages = {}, pmid = {39065765}, issn = {1424-8247}, support = {RSP2024R505//King Saud University/ ; }, abstract = {This study utilized Aspergillus flavus to produce selenium nanoparticles (Se-NPs) in an environmentally friendly and ecologically sustainable manner, targeting several medicinal applications. These biosynthesized Se-NPs were meticulously characterized using X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, transmission electron microscope (TEM), and UV-visible spectroscopy (UV), revealing their spherical shape and size ranging between 28 and 78 nm. We conducted further testing of Se-NPs to evaluate their potential for biological applications, including antiviral, anticancer, antibacterial, antioxidant, and antibiofilm activities. The results indicate that biosynthesized Se-NPs could be effective against various pathogens, including Salmonella typhimurium (ATCC 14028), Bacillus pumilus (ATCC 14884), Staphylococcus aureus (ATCC 6538), Clostridium sporogenes (ATCC 19404), Escherichia coli (ATCC 8739), and Bacillus subtilis (ATCC 6633). Additionally, the biosynthesized Se-NPs exhibited anticancer activity against three cell lines: pancreatic carcinoma (PANC1), cervical cancer (Hela), and colorectal adenocarcinoma (Caco-2), with IC50 values of 177, 208, and 216 μg/mL, respectively. The nanoparticles demonstrated antiviral activity against HSV-1 and HAV, achieving inhibition rates of 66.4% and 15.1%, respectively, at the maximum non-toxic concentration, while also displaying antibiofilm and antioxidant properties. In conclusion, the biosynthesized Se-NPs by A. flavus present a promising avenue for various biomedical applications with safe usage.}, }
@article {pmid39065310, year = {2024}, author = {Van Rooyen, B and De Wit, M and Osthoff, G and Van Niekerk, J}, title = {Cactus Pear Mucilage (Opuntia spp.) as a Novel Functional Biopolymer: Mucilage Extraction, Rheology and Biofilm Development.}, journal = {Polymers}, volume = {16}, number = {14}, pages = {}, pmid = {39065310}, issn = {2073-4360}, abstract = {The investigation of novel, natural polymers has gained considerably more exposure for their desirable, often specific, functional properties. Multiple researchers have explored these biopolymers to determine their potential to address many food processing, packaging and environmental concerns. Mucilage from the cactus pear (Opuntia ficus-indica) is one such biopolymer that has been identified as possessing a functional potential that can be used in an attempt to enhance food properties and reduce the usage of non-biodegradable, petroleum-based packaging in the food industry. However, variations in the structural composition of mucilage and the different extraction methods that have been reported by researchers have considerably impacted mucilage's functional potential. Although not comparable, these factors have been investigated, with a specific focus on mucilage applications. The natural ability of mucilage to bind water, alter the rheology of a food system and develop biofilms are considered the major applications of mucilage's functional properties. Due to the variations that have been reported in mucilage's chemical composition, specifically concerning the proportions of uronic acids, mucilage's rheological and biofilm properties are influenced differently by changes in pH and a cross-linker. Exploring the factors influencing mucilage's chemical composition, while co-currently discussing mucilage functional applications, will prove valuable when evaluating mucilage's potential to be considered for future commercial applications. This review article, therefore, discusses and highlights the key factors responsible for mucilage's specific functional potential, while exploring important potential food processing and packaging applications.}, }
@article {pmid39065268, year = {2024}, author = {Cate, JD and Sullivan, YZ and King, MD}, title = {Inhibition of Microbial Growth and Biofilm Formation in Pure and Mixed Bacterial Samples.}, journal = {Microorganisms}, volume = {12}, number = {7}, pages = {}, pmid = {39065268}, issn = {2076-2607}, support = {5R21AI169046-02A1/NH/NIH HHS/United States ; CBET 2034048//NSF/ ; TEX09746//USDA NIFA Hatch Project/ ; }, abstract = {Hydraulic fracturing, or fracking, requires large amounts of water to extract fossil fuel from rock formations. As a result of hydraulic fracturing, the briny wastewater, often termed back-produced fracturing or fracking water (FW), is pumped into holding ponds. One of the biggest challenges with produced water management is controlling microbial activity that could reduce the pond water's reusable layer and pose a significant environmental hazard. This study focuses on the characterization of back-produced water that has been hydraulically fractured using chemical and biological analysis and the development of a high-throughput screening method to evaluate and predict the antimicrobial effect of four naturally and commercially available acidic inhibitors (edetic acid, boric acid, tannic acid, and lactic acid) on the growth of the FW microbiome. Liquid cultures and biofilms of two laboratory model strains, the vegetative Escherichia coli MG1655, and the spore-forming Bacillus atrophaeus (also known as Bacillus globigii, BG) bacteria, were used as reference microorganisms. Planktonic bacteria in FW were more sensitive to antimicrobials than sessile bacteria in biofilms. Spore-forming BG bacteria exhibited more sensitivity to acidic inhibitors than the vegetative E. coli cells. Organic acids were the most effective bacterial growth inhibitors in liquid culture and biofilm.}, }
@article {pmid39065121, year = {2024}, author = {Shi, W and Zhang, Q and Li, H and Du, D and Ma, X and Wang, J and Jiang, J and Liu, C and Kou, L and Ren, J}, title = {Biofilm Formation, Motility, and Virulence of Listeria monocytogenes Are Reduced by Deletion of the Gene lmo0159, a Novel Listerial LPXTG Surface Protein.}, journal = {Microorganisms}, volume = {12}, number = {7}, pages = {}, pmid = {39065121}, issn = {2076-2607}, support = {32160834//National Natural Science Foundation of China/ ; 32160833//National Natural Science Foundation of China/ ; 32260895//National Natural Science Foundation of China/ ; RCZK202042//Shihezi University high level talent research launch project/ ; }, abstract = {Listeria monocytogenes (L. monocytogenes) is a foodborne pathogen that causes listeriosis in humans and other animals. Surface proteins with the LPXTG motif have important roles in the virulence of L. monocytogenes. Lmo0159 is one such protein, but little is known about its role in L. monocytogenes virulence, motility, and biofilm formation. Here, we constructed and characterized a deletion mutant of lmo0159 (∆lmo0159). We analyzed not only the capacity of biofilm formation, motility, attachment, and intracellular growth in different cell types but also LD50; bacterial load in mice's liver, spleen, and brain; expression of virulence genes; and survival time of mice after challenge. The results showed that the cross-linking density of the biofilm of ∆lmo0159 strain was lower than that of WT by microscopic examination. The expression of biofilm-formation and virulence genes also decreased in the biofilm state. Subsequently, the growth and motility of ∆lmo0159 in the culture medium were enhanced. Conversely, the growth and motility of L. monocytogenes were attenuated by ∆lmo0159 at both the cellular and mouse levels. At the cellular level, ∆lmo0159 reduced plaque size; accelerated scratch healing; and attenuated the efficiency of adhesion, invasion, and intracellular proliferation in swine intestinal epithelial cells (SIEC), RAW264.7, mouse-brain microvascular endothelial cells (mBMEC), and human-brain microvascular endothelial cells (hCMEC/D3). The expression of virulence genes was also inhibited. At the mouse level, the LD50 of the ∆lmo0159 strain was 10[0.97] times higher than that of the WT strain. The bacterial load of the ∆lmo0159 strain in the liver and spleen was lower than that of the WT strain. In a mouse model of intraperitoneal infection, the deletion of the lmo0159 gene significantly prolonged the survival time of the mice, suggesting that the lmo0159 deletion mutant also exhibited reduced virulence. Thus, our study identified lmo0159 as a novel virulence factor among L. monocytogenes LPXTG proteins.}, }
@article {pmid39065070, year = {2024}, author = {Burdová, A and Véghová, A and Minarovičová, J and Drahovská, H and Kaclíková, E}, title = {The Relationship between Biofilm Phenotypes and Biofilm-Associated Genes in Food-Related Listeria monocytogenes Strains.}, journal = {Microorganisms}, volume = {12}, number = {7}, pages = {}, pmid = {39065070}, issn = {2076-2607}, support = {313011V336//European Regional Development Fund/ ; 720/2023/MPRVSR-930//Ministry of Agriculture and Rural Development of the Slovak Republic/ ; }, abstract = {Listeria monocytogenes is an important pathogen responsible for listeriosis, a serious foodborne illness associated with high mortality rates. Therefore, L. monocytogenes is considered a challenge for the food industry due to the ability of some strains to persist in food-associated environments. Biofilm production is presumed to contribute to increased L. monocytogenes resistance and persistence. The aims of this study were to (1) assess the biofilm formation of L. monocytogenes isolates from a meat processing facility and sheep farm previously characterized and subjected to whole-genome sequencing and (2) perform a comparative genomic analysis to compare the biofilm formation and the presence of a known set of biofilm-associated genes and related resistance or persistence markers. Among the 37 L. monocytogenes isolates of 15 sequence types and four serogroups involved in this study, 14%, 62%, and 24% resulted in the formation of weak, moderate, and strong biofilm, respectively. Increased biofilm-forming ability was associated with the presence of the stress survival islet 1 (SSI-1), inlL, and the truncated inlA genes. Combining the phenotypic and genotypic data may contribute to understanding the relationships between biofilm-associated genes and L. monocytogenes biofilm-forming ability, enabling improvement in the control of this foodborne pathogen.}, }
@article {pmid39065026, year = {2024}, author = {Li, Z and Zhang, M and Lei, G and Lu, X and Yang, X and Kan, B}, title = {A Single Base Change in the csgD Promoter Resulted in Enhanced Biofilm in Swine-Derived Salmonella Typhimurium.}, journal = {Microorganisms}, volume = {12}, number = {7}, pages = {}, pmid = {39065026}, issn = {2076-2607}, support = {2022YFC2303900//the National Key Research and Development Program of China/ ; }, abstract = {Pathogenic Salmonella strains causing gastroenteritis typically can colonize and proliferate in the intestines of multiple host species. They retain the ability to form red dry and rough (rdar) biofilms, as seen in Salmonella enterica serovar Typhimurium. Conversely, Salmonella serovar like Typhi, which can cause systemic infections and exhibit host restriction, are rdar-negative. In this study, duck-derived strains and swine-derived strains of S. Typhimurium locate on independent phylogenetic clades and display relative genomic specificity. The duck isolates appear more closely related to human blood isolates and invasive non-typhoidal Salmonella (iNTS), whereas the swine isolates were more distinct. Phenotypically, compared to duck isolates, swine isolates exhibited enhanced biofilm formation that was unaffected by the temperature. The transcriptomic analysis revealed the upregulation of csgDEFG transcription as the direct cause. This upregulation may be mainly attributed to the enhanced promoter activity caused by the G-to-T substitution at position -44 of the csgD promoter. Swine isolates have created biofilm polymorphisms by altering a conserved base present in Salmonella Typhi, iNTS, and most Salmonella Typhimurium (such as duck isolates). This provides a genomic characteristics perspective for understanding Salmonella transmission cycles and evolution.}, }
@article {pmid39063012, year = {2024}, author = {Liu, X and Hu, J and Wang, W and Yang, H and Tao, E and Ma, Y and Sha, S}, title = {Mycobacterial Biofilm: Mechanisms, Clinical Problems, and Treatments.}, journal = {International journal of molecular sciences}, volume = {25}, number = {14}, pages = {}, pmid = {39063012}, issn = {1422-0067}, support = {LJKZ0846//Scientific Research Program of Liaoning Province, China/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; Humans ; Animals ; *Antitubercular Agents/pharmacology/therapeutic use ; Mycobacterium tuberculosis/drug effects/physiology ; Tuberculosis/drug therapy/microbiology ; Bacterial Proteins/metabolism/genetics ; Virulence ; }, abstract = {Tuberculosis (TB) remains a threat to human health worldwide. Mycobacterium tuberculosis (Mtb) and other nontuberculous mycobacteria (NTM) can form biofilms, and in vitro and animal experiments have shown that biofilms cause serious drug resistance and mycobacterial persistence. Deeper investigations into the mechanisms of mycobacterial biofilm formation and, consequently, the exploration of appropriate antibiofilm treatments to improve the efficiency of current anti-TB drugs will be useful for curing TB. In this review, the genes and molecules that have been recently reported to be involved in mycobacterial biofilm development, such as ABC transporter, Pks1, PpiB, GroEL1, MprB, (p)ppGpp, poly(P), and c-di-GMP, are summarized. Biofilm-induced clinical problems, including biofilm-related infections and enhanced virulence, as well as their possible mechanisms, are also discussed in detail. Moreover, we also illustrate newly synthesized anti-TB agents that target mycobacterial biofilm, as well as some assistant methods with high efficiency in reducing biofilms in hosts, such as the use of nanoparticles.}, }
@article {pmid39062838, year = {2024}, author = {Zhang, Y and Zhao, X and Wang, J and Liao, L and Qin, H and Zhang, R and Li, C and He, Y and Huang, S}, title = {VmsR, a LuxR-Type Regulator, Contributes to Virulence, Cell Motility, Extracellular Polysaccharide Production and Biofilm Formation in Xanthomonas oryzae pv. oryzicola.}, journal = {International journal of molecular sciences}, volume = {25}, number = {14}, pages = {}, pmid = {39062838}, issn = {1422-0067}, support = {2020GXNSFDA297026//Guangxi Natural Science Foundation/ ; 32360045//National Natural Science Foundation of China/ ; 32060600//National Natural Science Foundation of China/ ; }, mesh = {*Xanthomonas/pathogenicity/genetics/metabolism ; *Biofilms/growth &amp; development ; *Polysaccharides, Bacterial/metabolism/biosynthesis ; Virulence/genetics ; *Gene Expression Regulation, Bacterial ; *Bacterial Proteins/genetics/metabolism ; Trans-Activators/genetics/metabolism ; Oryza/microbiology ; Plant Diseases/microbiology ; Promoter Regions, Genetic ; Repressor Proteins/genetics/metabolism ; }, abstract = {LuxR-type regulators play pivotal roles in regulating numerous bacterial processes, including bacterial motility and virulence, thereby exerting a significant influence on bacterial behavior and pathogenicity. Xanthomonas oryzae pv. oryzicola, a rice pathogen, causes bacterial leaf streak. Our research has identified VmsR, which is a response regulator of the two-component system (TCS) that belongs to the LuxR family. These findings of the experiment reveal that VmsR plays a crucial role in regulating pathogenicity, motility, biofilm formation, and the production of extracellular polysaccharides (EPSs) in Xoc GX01. Notably, our study shows that the vmsR mutant exhibits a reduced swimming motility but an enhanced swarming motility. Furthermore, this mutant displays decreased virulence while significantly increasing EPS production and biofilm formation. We have uncovered that VmsR directly interacts with the promoter regions of fliC and fliS, promoting their expression. In contrast, VmsR specifically binds to the promoter of gumB, resulting in its downregulation. These findings indicate that the knockout of vmsR has profound effects on virulence, motility, biofilm formation, and EPS production in Xoc GX01, providing insights into the intricate regulatory network of Xoc.}, }
@article {pmid39062493, year = {2024}, author = {Vadillo-Rodríguez, V and Fernández-Babiano, I and Pérez-Giraldo, C and Fernández-Calderón, MC}, title = {Anti-Biofilm Perspectives of Propolis against Staphylococcus epidermidis Infections.}, journal = {Biomolecules}, volume = {14}, number = {7}, pages = {}, pmid = {39062493}, issn = {2218-273X}, support = {PID2022-140422OB-I00//Agencia Estatal de Investigaci&#xf3;n/ ; Una manera de hacer Europa.//FEDER Una manera de hacer Europa./ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Staphylococcus epidermidis/drug effects/physiology ; *Propolis/pharmacology/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Microbial Sensitivity Tests ; Humans ; Bacterial Adhesion/drug effects ; Staphylococcal Infections/drug therapy/microbiology ; }, abstract = {Staphylococcus epidermis has emerged as the main causative agent of medical device-related infections. Their major pathogenicity factor lies in its ability to adhere to surfaces and proliferate into biofilms, which increase their resistance to antibiotics. The main objective of this study was to evaluate the use and the mechanism of action of an ethanolic extract of Spanish propolis (EESP) as a potential alternative for preventing biofilm-related infections caused by S. epidermidis. The chemical composition of propolis is reported and its antibacterial activity against several strains of S. epidermidis with different biofilm-forming capacities evaluated. The influence of sub-inhibitory concentrations (sub-MICs) of EESP on their growth, physicochemical surface properties, adherence, and biofilm formation were studied. EESP interferes with planktonic cells, homogenizing their physicochemical surface properties and introducing a significant delay in their growth. The adherence and biofilms at the EESP concentrations investigated were decreased up to 90.5% among the strains. Microscopic analysis indicated that the planktonic cells that survived the treatment were the ones that adhere and proliferate on the surfaces. The results obtained suggest that the EESP has a high potential to be used as an inhibitor of both the adhesion and biofilm formation of S. epidermidis.}, }
@article {pmid39061313, year = {2024}, author = {Pirușcă, IA and Balaure, PC and Grumezescu, V and Irimiciuc, SA and Oprea, OC and Bîrcă, AC and Vasile, B and Holban, AM and Voinea, IC and Stan, MS and Trușcă, R and Grumezescu, AM and Croitoru, GA}, title = {New Fe3O4-Based Coatings with Enhanced Anti-Biofilm Activity for Medical Devices.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {7}, pages = {}, pmid = {39061313}, issn = {2079-6382}, abstract = {With the increasing use of invasive, interventional, indwelling, and implanted medical devices, healthcare-associated infections caused by pathogenic biofilms have become a major cause of morbidity and mortality. Herein, we present the fabrication, characterization, and in vitro evaluation of biocompatibility and anti-biofilm properties of new coatings based on Fe3O4 nanoparticles (NPs) loaded with usnic acid (UA) and ceftriaxone (CEF). Sodium lauryl sulfate (SLS) was employed as a stabilizer and modulator of the polarity, dispersibility, shape, and anti-biofilm properties of the magnetite nanoparticles. The resulting Fe3O4 functionalized NPs, namely Fe3O4@SLS, Fe3O4@SLS/UA, and Fe3O4@SLS/CEF, respectively, were prepared by co-precipitation method and fully characterized by XRD, TEM, SAED, SEM, FTIR, and TGA. They were further used to produce nanostructured coatings by matrix-assisted pulsed laser evaporation (MAPLE) technique. The biocompatibility of the coatings was assessed by measuring the cell viability, lactate dehydrogenase release, and nitric oxide level in the culture medium and by evaluating the actin cytoskeleton morphology of murine pre-osteoblasts. All prepared nanostructured coatings exhibited good biocompatibility. Biofilm growth inhibition ability was tested at 24 h and 48 h against Staphylococcus aureus and Pseudomonas aeruginosa as representative models for Gram-positive and Gram-negative bacteria. The coatings demonstrated good biocompatibility, promoting osteoblast adhesion, migration, and growth without significant impact on cell viability or morphology, highlighting their potential for developing safe and effective antibacterial surfaces.}, }
@article {pmid39061305, year = {2024}, author = {Mishra, A and Aggarwal, A and Khan, F}, title = {Medical Device-Associated Infections Caused by Biofilm-Forming Microbial Pathogens and Controlling Strategies.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {7}, pages = {}, pmid = {39061305}, issn = {2079-6382}, support = {RS-2023-00241461//National Research Foundation/ ; }, abstract = {Hospital-acquired infections, also known as nosocomial infections, include bloodstream infections, surgical site infections, skin and soft tissue infections, respiratory tract infections, and urinary tract infections. According to reports, Gram-positive and Gram-negative pathogenic bacteria account for up to 70% of nosocomial infections in intensive care unit (ICU) patients. Biofilm production is a main virulence mechanism and a distinguishing feature of bacterial pathogens. Most bacterial pathogens develop biofilms at the solid-liquid and air-liquid interfaces. An essential requirement for biofilm production is the presence of a conditioning film. A conditioning film provides the first surface on which bacteria can adhere and fosters the growth of biofilms by creating a favorable environment. The conditioning film improves microbial adherence by delivering chemical signals or generating microenvironments. Microorganisms use this coating as a nutrient source. The film gathers both inorganic and organic substances from its surroundings, or these substances are generated by microbes in the film. These nutrients boost the initial growth of the adhering bacteria and facilitate biofilm formation by acting as a food source. Coatings with combined antibacterial efficacy and antifouling properties provide further benefits by preventing dead cells and debris from adhering to the surfaces. In the present review, we address numerous pathogenic microbes that form biofilms on the surfaces of biomedical devices. In addition, we explore several efficient smart antiadhesive coatings on the surfaces of biomedical device-relevant materials that manage nosocomial infections caused by biofilm-forming microbial pathogens.}, }
@article {pmid39061301, year = {2024}, author = {D'Aquila, P and De Rose, E and Sena, G and Scorza, A and Cretella, B and Passarino, G and Bellizzi, D}, title = {Quorum Quenching Approaches against Bacterial-Biofilm-Induced Antibiotic Resistance.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {7}, pages = {}, pmid = {39061301}, issn = {2079-6382}, abstract = {With the widespread phenomenon of antibiotic resistance and the diffusion of multiple drug-resistant bacterial strains, enormous efforts are being conducted to identify suitable alternative agents against pathogenic microorganisms. Since an association between biofilm formation and antibiotic resistance phenotype has been observed, a promising strategy pursued in recent years focuses on controlling and preventing this formation by targeting and inhibiting the Quorum Sensing (QS) system, whose central role in biofilm has been extensively demonstrated. Therefore, the research and development of Quorum Quenching (QQ) compounds, which inhibit QS, has gradually attracted the attention of researchers and has become a new strategy for controlling harmful microorganisms. Among these, a number of both natural and synthetic compounds have been progressively identified as able to interrupt the intercellular communication within a microbial community and the adhesion to a surface, thus disintegrating mature/preformed biofilms. This review describes the role played by QS in the formation of bacterial biofilms and then focuses on the mechanisms of different natural and synthetic QS inhibitors (QSIs) exhibiting promising antibiofilm ability against Gram-positive and Gram-negative bacterial pathogens and on their applications as biocontrol strategies in various fields.}, }
@article {pmid39061295, year = {2024}, author = {Santajit, S and Tunyong, W and Horpet, D and Binmut, A and Kong-Ngoen, T and Wisessaowapak, C and Thavorasak, T and Pumirat, P and Indrawattana, N}, title = {Unveiling the Antimicrobial, Anti-Biofilm, and Anti-Quorum-Sensing Potential of Paederia foetida Linn. Leaf Extract against Staphylococcus aureus: An Integrated In Vitro-In Silico Investigation.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {7}, pages = {}, pmid = {39061295}, issn = {2079-6382}, support = {RGNS 64-205//Office of the Permanent Secretary, Ministry of Higher Education, Science, Research and Innova-tion (OPS MHESI), Thailand Science Research and Innovation (TSRI)/ ; FF-113/2567//Mahidol University (Fundamental Fund: fiscal year 2024 by National Science Research and In-novation Fund (NSRF))./ ; }, abstract = {Antimicrobial resistance poses a global health threat, with Staphylococcus aureus emerging as a notorious pathogen capable of forming stubborn biofilms and regulating virulence through quorum sensing (QS). In the quest for novel therapeutic strategies, this groundbreaking study unveils the therapeutic potential of Paederia foetida Linn., an Asian medicinal plant containing various bioactive compounds, contributing to its antimicrobial activities, in the battle against S. aureus. Through a comprehensive approach, we investigated the effect of ethanolic P. foetida leaf extract on S. aureus biofilms, QS, and antimicrobial activity. The extract exhibited promising inhibitory effects against S. aureus including the biofilm-forming strain and MRSA. Real-time PCR analysis revealed significant downregulation of key virulence and biofilm genes, suggesting interference with QS. Biofilm assays quantified the extract's ability to disrupt and prevent biofilm formation. LC-MS/MS analysis identified quercetin and kaempferol glycosides as potential bioactive constituents, while molecular docking studies explored their binding to the QS transcriptional regulator SarA. Computational ADMET predictions highlighted favorable intestinal absorption but potential P-glycoprotein interactions limiting oral bioavailability. While promising anti-virulence effects were demonstrated, the high molecular weights and excessive hydrogen bond donors/acceptors of the flavonoid glycosides raise concerns regarding drug-likeness and permeability. This integrated study offers valuable insights for developing novel anti-virulence strategies to combat antimicrobial resistance.}, }
@article {pmid39061287, year = {2024}, author = {Sena, G and De Rose, E and Crudo, M and Filippelli, G and Passarino, G and Bellizzi, D and D'Aquila, P}, title = {Essential Oils from Southern Italian Aromatic Plants Synergize with Antibiotics against Escherichia coli, Pseudomonas aeruginosa and Enterococcus faecalis Cell Growth and Biofilm Formation.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {7}, pages = {}, pmid = {39061287}, issn = {2079-6382}, abstract = {The spread of antibiotic-resistant pathogens has prompted the development of novel approaches to identify molecules that synergize with antibiotics to enhance their efficacy. This study aimed to investigate the effects of ten Essential Oils (EOs) on the activity of nine antibiotics in influencing growth and biofilm formation in Escherichia coli, Pseudomonas aeruginosa, and Enterococcus faecalis. The effects of the EOs alone and in combination with antibiotics on both bacterial growth and biofilm formation were analyzed by measuring the MIC values through the broth microdilution method and the crystal violet assay, respectively. All EOs inhibited the growth of E. coli (1.25 ≤ MIC ≤ 5 mg/mL) while the growth of P. aeruginosa and E. faecalis was only affected by EOs from Origanum vulgare, (MIC = 5 mg/mL) and O. vulgare (MIC = 1.25 mg/mL) and Salvia rosmarinus (MIC = 5 mg/mL), respectively. In E. coli, most EOs induced a four- to sixteen-fold reduction in the MIC values of ampicillin, ciprofloxacin, ceftriaxone, gentamicin, and streptomycin, while in E. faecalis such a reduction is observed in combinations of ciprofloxacin with C. nepeta, C. bergamia, C. limon, C. reticulata, and F. vulgare, of gentamicin with O. vulgare, and of tetracycline with C. limon and O. vulgare. A smaller effect was observed in P. aeruginosa, in which only C. bergamia reduced the concentration of tetracycline four-fold. EO-antibiotic combinations also inhibit the biofilm formation. More precisely, all EOs with ciprofloxacin in E. coli, tetracycline in P. aeruginosa, and gentamicin in E. faecalis showed the highest percentage of inhibition. Combinations induce up- and down-methylation of cytosines and adenines compared to EO or antibiotics alone. The study provides evidence about the role of EOs in enhancing the action of antibiotics by influencing key processes involved in resistance mechanisms such as biofilm formation and epigenetic changes. Synergistic interactions should be effectively considered in dealing with pathogenic microorganisms.}, }
@article {pmid39061277, year = {2024}, author = {Musa, L and Toppi, V and Stefanetti, V and Spata, N and Rapi, MC and Grilli, G and Addis, MF and Di Giacinto, G and Franciosini, MP and Casagrande Proietti, P}, title = {High Biofilm-Forming Multidrug-Resistant Salmonella Infantis Strains from the Poultry Production Chain.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {7}, pages = {}, pmid = {39061277}, issn = {2079-6382}, abstract = {The ability of Salmonella species to adhere to surfaces and form biofilms, leading to persistent environmental reservoirs, might represent a direct link between environmental contamination and food processing contamination. The purpose of this study was to investigate the biofilm-forming ability of 80 multidrug-resistant (MDR) and extended-spectrum beta-lactamase (ESBL) producing Salmonella enterica serovar Infantis strains isolated from the broiler food chain production through whole genome sequencing (WGS), PCR, and morphotype association assays. Biofilm formation was quantified by testing the strains at two different temperatures, using 96-well polystyrene plates. The rough and dry colony (rdar) morphotype was assessed visually on Congo red agar (CRA) plates. Based on our results, all tested S. Infantis strains produced biofilm at 22 °C with an rdar morphotype, while at 37 °C, all the isolates tested negative, except one positive. Most isolates (58.75%) exhibited strong biofilm production, while 36.25% showed moderate production. Only 5 out of 80 (6.25%) were weak biofilm producers. WGS analysis showed the presence of the fim cluster (fimADF) and the csg cluster (csgBAC and csgDEFG), also described in S. Typhimurium, which are responsible for fimbriae production. PCR demonstrated the presence of csgD, csgB, and fimA in all 80 S. Infantis strains. To our knowledge, this is the first study comparing the effects of two different temperatures on the biofilm formation capacity of ESBL producing S. Infantis from the broiler production chain. This study highlights that the initial biofilm components, such as curli and cellulose, are specifically expressed at lower temperatures. It is important to emphasize that within the broiler farm, the environmental temperature ranges between 18-22 °C, which is the optimum temperature for in vitro biofilm formation by Salmonella spp. This temperature range facilitates the expression of biofilm-associated genes, contributing to the persistence of S. Infantis in the environment. This complicates biosecurity measures and makes disinfection protocols on the farm and in the production chain more difficult, posing serious public health concerns.}, }
@article {pmid39060129, year = {2024}, author = {Bian, C and Lyu, M and Zhu, M and Liu, M and Xie, X and Weir, MD and Hack, GD and Masri, R and Zhang, K and Bai, Y and Xu, HHK and Zhang, N}, title = {Novel antibacterial orthodontic elastomeric ligature with oral biofilm-regulatory ability to prevent enamel demineralization.}, journal = {Dental materials : official publication of the Academy of Dental Materials}, volume = {40}, number = {10}, pages = {1534-1545}, doi = {10.1016/j.dental.2024.07.015}, pmid = {39060129}, issn = {1879-0097}, mesh = {*Biofilms/drug effects ; *Elastomers ; *Anti-Bacterial Agents/pharmacology ; *Tooth Demineralization/prevention &amp; control ; *Methacrylates/pharmacology ; Materials Testing ; Orthodontic Appliances/microbiology ; In Vitro Techniques ; Streptococcus mutans/drug effects ; Real-Time Polymerase Chain Reaction ; Dental Plaque/microbiology/prevention &amp; control ; Dental Enamel/drug effects ; }, abstract = {OBJECTIVES: To synthesize a novel antibacterial orthodontic elastomeric ligature incorporating dimethylaminohexadecyl methacrylate (DMAHDM) for the first time to prevent enamel demineralization during orthodontic therapy.<br><br>METHODS: Various mass fractions of DMAHDM (ranging from 0&#xa0;% to 20&#xa0;%) were grafted onto commercial elastomeric ligatures using an ultraviolet photochemical grafting method and were characterized. The optimal DMAHDM concentration was determined based on biocompatibility and mechanical properties, and the antibacterial efficacy was evaluated in a whole-plaque biofilm model. TaqMan real-time polymerase chain reaction and fluorescence in situ hybridization were used to assess the microbial regulatory ability of the multispecies biofilms. Furthermore, an in vitro tooth demineralization model was established to explore its preventive effects on enamel demineralization. Statistical analysis involved a one-way analysis of variance and LSD post hoc tests at a significance level of 0.05.<br><br>RESULTS: The elastomeric ligature containing 2&#xa0;% mass fraction of DMAHDM exhibited excellent mechanical properties, favorable biocompatibility, and the most effective antibacterial ability against microorganisms, which decreased by almost two logarithms (P&#xa0;<&#xa0;0.05). It significantly reduced the proportion of Streptococcus mutans in the multispecies plaque biofilm by 25&#xa0;% at 72&#xa0;h, leading to an enhanced biofilm microenvironment. Moreover, the novel elastomeric ligature demonstrated an obvious preventive effect on enamel demineralization, with an elastic modulus 30&#xa0;% higher and hardness 62&#xa0;% higher than those of the control group within 3 months (P&#xa0;<&#xa0;0.05).<br><br>SIGNIFICANCE: The integration of DMAHDM with an elastomeric ligature holds significant promise for regulating biofilms and preventing enamel demineralization in orthodontic applications.}, }
@article {pmid39059950, year = {2024}, author = {Byun, KH and Kang, M and Seon Koo, M and Lim, MC and Sik Ok, G and Jung Kim, H}, title = {Potential risk of biofilm-forming Bacillus cereus group in fresh-cut lettuce production chain.}, journal = {Food research international (Ottawa, Ont.)}, volume = {191}, number = {}, pages = {114692}, doi = {10.1016/j.foodres.2024.114692}, pmid = {39059950}, issn = {1873-7145}, mesh = {*Lactuca/microbiology ; *Biofilms/growth &amp; development ; *Bacillus cereus/genetics/metabolism/isolation &amp; purification/physiology ; *Enterotoxins/genetics/metabolism ; *Food Microbiology ; Bacillus thuringiensis/genetics/physiology ; Spores, Bacterial/genetics ; Anti-Bacterial Agents/pharmacology ; Food Contamination/analysis ; Microbial Sensitivity Tests ; Foodborne Diseases/microbiology ; Genotype ; }, abstract = {Bacillus cereus and Bacillus thuringiensis, which belong to the B. cereus group, are widely distributed in nature and can cause food poisoning symptoms. In this study, we collected 131 isolates belonging to the B. cereus group, comprising 124B. cereus and seven B. thuringiensis isolates, from fresh-cut lettuce production chain and investigated their potential risk by analyzing genotypic (enterotoxin and emetic toxin gene profiles) and phenotypic (antibiotic susceptibility, sporulation, and biofilm formation) characteristics. Enterotoxin genes were present only in B. cereus, whereas the emetic toxin gene was not detected in any of the B. cereus isolates. All isolates were susceptible to vancomycin, which is a last resort for treating B. cereus group infection symptoms, but generally resistant to β-lactam antimicrobials, and had the ability to form spores (at an average sporulation rate of 24.6 %) and biofilms at 30 °C. Isolates that formed strong biofilms at 30 °C had a superior possibility of forming a dense biofilm by proliferating at 10 °C compared to other isolates. Additionally, confocal laser scanning microscopy (CLSM) images revealed a notable presence of spores within the submerged biofilm formed at 10 °C, and the strengthened attachment of biofilm inner cells to the substrate was further revealed through biofilm structure parameters analysis. Collectively, our study revealed the prevalence and contamination levels of B. cereus and B. thuringiensis at fresh-cut lettuce production chain and investigated their genotypic and phenotypic characteristics, aiming to provide valuable insights for the development of potential risk management strategies to ensure food safety, especially along the cold chain.}, }
@article {pmid39059895, year = {2024}, author = {Bombelli, A and Araya-Cloutier, C and Abee, T and den Besten, HMW}, title = {Disinfectant efficacy of glabridin against dried and biofilm cells of Listeria monocytogenes and the impact of residual organic matter.}, journal = {Food research international (Ottawa, Ont.)}, volume = {191}, number = {}, pages = {114613}, doi = {10.1016/j.foodres.2024.114613}, pmid = {39059895}, issn = {1873-7145}, mesh = {*Listeria monocytogenes/drug effects/growth &amp; development ; *Isoflavones/pharmacology ; *Biofilms/drug effects/growth &amp; development ; *Phenols/pharmacology ; *Food Microbiology ; Disinfectants/pharmacology ; Microbial Sensitivity Tests ; Stainless Steel ; Anti-Bacterial Agents/pharmacology ; Animals ; }, abstract = {Glabridin is an antimicrobial compound which can be extracted from plants, such as liquorice (Glycyrrhiza glabra) roots. Although its activity against foodborne pathogens and spoilage microorganisms has already been reported, the investigation of potential applications as a surface disinfectant is still largely unexplored. Hence, this study evaluated the disinfectant efficacy of glabridin against Listeria monocytogenes. The activity of glabridin was first tested in vitro in a nutrient-rich medium against eight strains of L. monocytogenes, including food isolates and the model strain EGDe. The tested strains showed similar susceptibility with minimal inhibitory and bactericidal concentrations of 12.5 µg/mL and 25 µg/mL, respectively. Subsequently, L. monocytogenes L6, FBR17 and EGDe were selected to assess the efficacy of glabridin against dried cells (according to the European standard EN 13697:2015 + A1:2019) and biofilm cells on stainless steel surfaces. Moreover, the impact of food residual organic matter was investigated using skim milk, cantaloupe and smoked salmon solution as soiling components. Our results showed that applying 200 µg/mL of glabridin resulted in a substantial reduction (>3 log10) of dried and biofilm cells of L. monocytogenes in standard conditions (i.e. low level of residual organic matter). Cantaloupe soiling components slightly reduced the activity of glabridin, while the efficacy of glabridin when tested with salmon and skim milk residuals was substantially affected. Comparative analysis using standardized protein contents provided evidence that the type of food matrices and type of proteins may impact the activity of glabridin as a disinfectant. Overall, this study showed low strain variability for the activity of glabridin against L. monocytogenes and shed light on the possible application of this natural antimicrobial compound as a surface disinfectant.}, }
@article {pmid39059770, year = {2024}, author = {Tan, GSE and Chia, GJM and Thevasagayam, NM and Loy, SQD and Prakki, SRS and Lim, ZQ and Chua, JY and Chia, JWZ and Marimuthu, K and Vasoo, S and Ng, OT and Poh, BF and Ang, BSP}, title = {Whole-genome sequencing establishes persistence of biofilm-associated Pseudomonas aeruginosa detected from microbiological surveillance of gastrointestinal endoscopes.}, journal = {The Journal of hospital infection}, volume = {152}, number = {}, pages = {73-80}, doi = {10.1016/j.jhin.2024.07.007}, pmid = {39059770}, issn = {1532-2939}, mesh = {*Pseudomonas aeruginosa/genetics/isolation &amp; purification ; *Whole Genome Sequencing ; *Biofilms/growth &amp; development ; Humans ; *Endoscopes, Gastrointestinal/microbiology ; Singapore ; Equipment Contamination ; Pseudomonas Infections/microbiology ; }, abstract = {BACKGROUND: An increased incidence of Pseudomonas aeruginosa in microbiological surveillance (MS) cultures from gastrointestinal endoscopes was detected between March 2020 and March 2023 in Tan Tock Seng Hospital Singapore.<br><br>AIM: To describe the use of whole-genome sequencing (WGS) in this investigation.<br><br>METHODS: WGS was performed for all P.&#xa0;aeruginosa isolates with pairwise comparison of isolates to assess for genomic linkage. Comprehensive review of reprocessing practices and environmental sampling was performed.<br><br>FINDINGS: Twenty-two P.&#xa0;aeruginosa isolates were detected from endoscopic MS cultures. Fifteen (68%) isolates were available for WGS. Eighteen pairwise comparisons of isolates were made, of which 10 were found to be genomically linked. One endoscope had P.&#xa0;aeruginosa repeatedly cultured from subsequent MS that were genomically linked and persistent despite repeat endoscopic reprocessing, establishing the persistence of biofilm that could not be eradicated with routine reprocessing. All P.&#xa0;aeruginosa isolates cultured from other different endoscopes were genetically distinct. Investigation into reprocessing practices revealed the use of air/water valves connected to endoscopes during clinical use. Inspection of these valves revealed the presences of cracks and tears. All other environmental samples were negative.<br><br>CONCLUSION: The WGS findings helped to deprioritize common source contamination and supported the hypothesis of biofilm build-up within endoscopes, leading to repeatedly positive MS cultures that were genomically linked. This was possibly related to incomplete reprocessing of the damaged air/water valves, resulting in biofilm build-up. All faulty valves were changed and subsequently cleaned separately with ultrasonic cleaning followed by sterilization which resolved this incident.}, }
@article {pmid39059308, year = {2024}, author = {Xia, G and Sun, Z and Huang, J and Qi, J and Yao, J}, title = {Biodegradation of carbon disulfide and hydrogen sulfide using a moving bed biofilm reactor coupled with sulfur recycling: Performance, mechanism, and potential application.}, journal = {Journal of environmental management}, volume = {367}, number = {}, pages = {121943}, doi = {10.1016/j.jenvman.2024.121943}, pmid = {39059308}, issn = {1095-8630}, mesh = {*Biofilms ; *Bioreactors ; *Hydrogen Sulfide/metabolism ; *Biodegradation, Environmental ; *Sulfur/metabolism ; *Carbon Disulfide/metabolism ; Kinetics ; }, abstract = {In this work, a moving bed biofilm reactor (MBBR) was equipped for simultaneous biodegradation of CS2 and H2S. MBBR was started up and operated with different inlet concentrations and retention time; results indicated that approximately 81.9% CS2 and 93.9% H2S could be degraded, and the maximum elimination capacities of 209.3 g/(m[3]·h) and 138.5 g/(m[3]·h) were achieved for CS2 and H2S, respectively. The biodegradation mechanisms, including mass transfer, kinetics, and electron transfer, were then investigated. The mass transfer fraction and the maximum degradation rate per unit filter volume were calculated for evaluating the characteristics of mass transfer in MBBR. The variations of extracellular polymeric substances secretion, electron transport system activity and ATP enzyme activity showed that MBBR had an excellent performance for waste gas purification. Subsequently, the recovery of sulfur was explored via morphology, crystal structure, and generation kinetics, indicating that a modified Gompertz model could precisely describe the kinetics of sulfur recovery, and the product selectivity of 51.7% was achieved for sulfur. The microbial community analysis suggested that the dominant genera for biodegradation and sulfur recovery were Acidithiobacillus and Mycobacterium. Finally, MBBR system was validated for treatment of actual waste gas; results indicated that maximum elimination capacities of 134.1 g/(m[3]·h) and 117.1 g/(m[3]·h) were obtained for CS2 and H2S, respectively, suggesting that MBBR had the potential for application.}, }
@article {pmid39057985, year = {2024}, author = {Liu, C and Qian, R and Shi, W and Kou, L and Wang, J and Ma, X and Ren, H and Gao, S and Ren, J}, title = {EⅡB Mutation Reduces the Pathogenicity of Listeria monocytogenes by Negatively Regulating Biofilm Formation Ability, Infective Capacity, and Virulence Gene Expression.}, journal = {Veterinary sciences}, volume = {11}, number = {7}, pages = {}, pmid = {39057985}, issn = {2306-7381}, support = {RCZK202042//Shihezi University high level talent research launch project/ ; 32160833//National Natural Science Foundation of China/ ; 32160834//Natural Science Foundation of China/ ; }, abstract = {To explore the role of the membrane permease ⅡB (EⅡB) gene of Listeria pathogenicity island 4 (LIPI-4) in the virulence of Listeria monocytogenes, both an EⅡB deletion strain (∆EⅡB) and a complemented strain were constructed. In vitro experiments demonstrated that EⅡB deletion affected the biofilm formation ability of the wild-type strain (Lm928). Moreover, this deletion decreased the intracellular proliferation abilities of L. monocytogenes. Mice infected with ∆EⅡB survived longer and experienced less weight loss on days 1, 2, and 3 post-infection. The bacterial load in the liver tissue of ∆EⅡB-infected mice was significantly reduced, and a considerable decrease in the blood levels of inflammatory cytokines IL-β, IL-6, IL-10, and TNF-α were observed. Following EⅡB deletion, 65% (13/20) of genes were downregulated, 25% (5/20) were upregulated, and 10% (2/20) showed no change. These findings suggest that EⅡB deletion may reduce both the in vivo and in vitro virulence levels as well as the biofilm formation ability of Lm928 by downregulating the transcription levels of genes associated with virulence and biofilm formation. These findings provide a foundation for further examining the pathogenic mechanisms of LIPI-4 and EⅡB in L. monocytogenes.}, }
@article {pmid39057504, year = {2024}, author = {Alifah, N and Palungan, J and Ardayanti, K and Ullah, M and Nurkhasanah, AN and Mustopa, AZ and Lallo, S and Agustina, R and Yoo, JW and Hasan, N}, title = {Development of Clindamycin-Releasing Polyvinyl Alcohol Hydrogel with Self-Healing Property for the Effective Treatment of Biofilm-Infected Wounds.}, journal = {Gels (Basel, Switzerland)}, volume = {10}, number = {7}, pages = {}, pmid = {39057504}, issn = {2310-2861}, support = {96/IV/KS/11/2022 and 4538/UN4.22/PT.01.03/2022//This study was supported by the Indonesia Endowment Funds for Education (LPDP) and the National Research and Innovation Agency/Badan Riset dan Inovasi Nasional (BRIN) under the scheme of Program Riset dan Inovasi untuk Indonesia Maju (RIIM) with the contr/ ; }, abstract = {Self-healing hydrogels have good mechanical strength, can endure greater external force, and have the ability to heal independently, resulting in a strong bond between the wound and the material. Bacterial biofilm infections are life-threatening. Clindamycin (Cly) can be produced in the form of a self-healing hydrogel preparation. It is noteworthy that the antibacterial self-healing hydrogels show great promise as a wound dressing for bacterial biofilm infection. In this study, we developed a polyvinyl alcohol/borax (PVA/B) self-healing hydrogel wound dressing that releases Cly. Four ratios of PVA, B, and Cly were used to make self-healing hydrogels: F1 (4%:0.8%:1%), F2 (4%:1.2%:1%), F3 (1.6%:1%), and F4 (4%:1.6%:0). The results showed that F4 had the best physicochemical properties, including a self-healing duration of 11.81 ± 0.34 min, swelling ratio of 85.99 ± 0.12%, pH value of 7.63 ± 0.32, and drug loading of 98.34 ± 11.47%. The B-O-C cross-linking between PVA and borax caused self-healing, according to FTIR spectra. The F4 formula had a more equal pore structure in the SEM image. The PVA/B-Cly self-healing hydrogel remained stable at 6 ± 2 °C for 28 days throughout the stability test. The Korsmeyer-Peppas model released Cly by Fickian diffusion. In biofilm-infected mouse wounds, PVA/B-Cly enhanced wound healing and re-epithelialization. Our results indicate that the PVA/B-Cly produced in this work has reliable physicochemical properties for biofilm-infected wound therapy.}, }
@article {pmid39057422, year = {2024}, author = {Caudal, F and Roullier, C and Rodrigues, S and Dufour, A and Artigaud, S and Le Blay, G and Bazire, A and Petek, S}, title = {Anti-Biofilm Extracts and Molecules from the Marine Environment.}, journal = {Marine drugs}, volume = {22}, number = {7}, pages = {}, pmid = {39057422}, issn = {1660-3397}, support = {PhD SPOQS project//University of Southern Brittany/ ; PhD SPOQS project//Institut de Recherche pour le D&#xe9;veloppement/ ; ANR-17-EURE-0015 (MARESISTOME flagship project)//ISblue/ ; SPOQS project//Laboratoire des Sciences de l'Environnement Marin/ ; SPOQS project//Laboratoire de Biotechnologie et Chimie Marines/ ; }, mesh = {*Biofilms/drug effects ; *Aquatic Organisms ; *Anti-Bacterial Agents/pharmacology/chemistry/isolation &amp; purification ; Animals ; Bacteria/drug effects ; Humans ; Biological Products/pharmacology/isolation &amp; purification/chemistry ; }, abstract = {Pathogenic bacteria and their biofilms are involved in many diseases and represent a major public health problem, including the development of antibiotic resistance. These biofilms are known to cause chronic infections for which conventional antibiotic treatments are often ineffective. The search for new molecules and innovative solutions to combat these pathogens and their biofilms has therefore become an urgent need. The use of molecules with anti-biofilm activity would be a potential solution to these problems. The marine world is rich in micro- and macro-organisms capable of producing secondary metabolites with original skeletons. An interest in the chemical strategies used by some of these organisms to regulate and/or protect themselves against pathogenic bacteria and their biofilms could lead to the development of bioinspired, eco-responsible solutions. Through this original review, we listed and sorted the various molecules and extracts from marine organisms that have been described in the literature as having strictly anti-biofilm activity, without bactericidal activity.}, }
@article {pmid39057048, year = {2024}, author = {Eltabey, SM and Ibrahim, AH and Zaky, MM and Ibrahim, AE and Alrashdi, YBA and El Deeb, S and Saleh, MM}, title = {The Promising Effect of Ascorbic Acid and Paracetamol as Anti-Biofilm and Anti-Virulence Agents against Resistant Escherichia coli.}, journal = {Current issues in molecular biology}, volume = {46}, number = {7}, pages = {6805-6819}, pmid = {39057048}, issn = {1467-3045}, abstract = {Escherichia coli is a major cause of serious infections, with antibiotic resistance rendering many treatments ineffective. Hence, novel strategies to combat this pathogen are needed. Anti-virulence therapy is a promising new approach for the subsequent era. Recent research has examined the impact of sub-inhibitory doses of ascorbic acid and paracetamol on Escherichia coli virulence factors. This study evaluated biofilm formation, protease production, motility behavior, serum resistance, expression of virulence-regulating genes (using RT-PCR), and survival rates in a mouse model. Ascorbic acid significantly reduced biofilm formation, protease production, motility, and serum resistance from 100% in untreated isolates to 22-89%, 10-89%, 2-57%, and 31-35% in treated isolates, respectively. Paracetamol also reduced these factors from 100% in untreated isolates to 16-76%, 1-43%, 16-38%, and 31-35%, respectively. Both drugs significantly down-regulated virulence-regulating genes papC, fimH, ompT_m, stcE, fliC, and kpsMTII. Mice treated with these drugs had a 100% survival rate compared with 60% in the positive control group control inoculated with untreated bacteria. This study highlights the potential of ascorbic acid and paracetamol as anti-virulence agents, suggesting their use as adjunct therapies alongside conventional antimicrobials or as alternative treatments for resistant Escherichia coli infections.}, }
@article {pmid39055850, year = {2024}, author = {Outomuro Ruiz, JM and Gerner, E and Rahimi, S and Alarcón, LA and Mijakovic, I}, title = {Biofilm formation and dispersal of Staphylococcus aureus wound isolates in microtiter plate-based 2-D wound model.}, journal = {Heliyon}, volume = {10}, number = {13}, pages = {e33872}, pmid = {39055850}, issn = {2405-8440}, abstract = {Biofilm-associated wound infections in diabetic and immunocompromised patients are an increasing threat due to rising antibiotic resistance. Various wound models have been used to screen for efficient antiinfection treatments. However, results from in vitro models do not always match in vivo results, and this represents a bottleneck for development of new infection treatments. In this study, a static 2-D microtiter plate-based biofilm model was tested for growing clinically relevant Staphylococcus aureus wound isolates in various operating conditions, seeking to identify an optimal setup that would yield physiologically relevant results. Specifically, the tested variables included wound-mimicking growth media, precoating of surface with different proteins, multiwell plates with various surface properties, and the effect of bacterial pre-attachment step. Our results indicated that protein precoating is a key factor for supporting biofilm growth. The same wound isolate responded with significant differences in biofilm formation to different wound-mimicking media. Biofilm dispersal, as a proxy for effectiveness of antibiofilm treatments, was also investigated in response to proteinase K. The dispersal effect of proteinase K showed that the biofilm dispersal is contingent upon the specific wound isolate, with isolates CCUG 35571 and ATCC 6538 showing considerable dispersal responses. In conclusion, this study observed a higher biofilm formation in isolates when a protein precoating of collagen type I was applied but being dependent on the growth media selected. That is why we recommend to use simulated wound fluid or a wound-mimicking growth media to perform similar studies. Furthermore, proteinase K is suggested as an important factor that could affect biofilm dispersal within such models, since biofilm dispersal was induced in isolates CCUG 35571 and ATCC 6538 in simulated wound fluid on precoated collagen type I plates.}, }
@article {pmid39054781, year = {2024}, author = {Li, Y and Liang, X and Chen, N and Yuan, X and Wang, J and Wu, Q and Ding, Y}, title = {The promotion of biofilm dispersion: a new strategy for eliminating foodborne pathogens in the food industry.}, journal = {Critical reviews in food science and nutrition}, volume = {}, number = {}, pages = {1-25}, doi = {10.1080/10408398.2024.2354524}, pmid = {39054781}, issn = {1549-7852}, abstract = {Food safety is a critical global concern due to its direct impact on human health and overall well-being. In the food processing environment, biofilm formation by foodborne pathogens poses a significant problem as it leads to persistent and high levels of food contamination, thereby compromising the quality and safety of food. Therefore, it is imperative to effectively remove biofilms from the food processing environment to ensure food safety. Unfortunately, conventional cleaning methods fall short of adequately removing biofilms, and they may even contribute to further contamination of both equipment and food. It is necessary to develop alternative approaches that can address this challenge in food industry. One promising strategy in tackling biofilm-related issues is biofilm dispersion, which represents the final step in biofilm development. Here, we discuss the biofilm dispersion mechanism of foodborne pathogens and elucidate how biofilm dispersion can be employed to control and mitigate biofilm-related problems. By shedding light on these aspects, we aim to provide valuable insights and solutions for effectively addressing biofilm contamination issues in food industry, thus enhancing food safety and ensuring the well-being of consumers.}, }
@article {pmid39054303, year = {2024}, author = {Javid Moghadam, M and Maktabi, S and Zarei, M and Mahmoodi, P}, title = {Controlling Staphylococcus aureus biofilm on food contact surfaces: the efficacy of Oliveria decumbens essential oil and its implications on biofilm-related genes.}, journal = {Journal of applied microbiology}, volume = {135}, number = {8}, pages = {}, doi = {10.1093/jambio/lxae187}, pmid = {39054303}, issn = {1365-2672}, support = {//Shahid Chamran University of Ahvaz/ ; }, mesh = {*Biofilms/drug effects ; *Staphylococcus aureus/drug effects/genetics/physiology ; *Oils, Volatile/pharmacology ; *Microbial Sensitivity Tests ; Stainless Steel ; Anti-Bacterial Agents/pharmacology ; Food Microbiology ; }, abstract = {AIMS: This study aimed to investigate the effect of Oliveria decumbens essential oil (Od-EO) on the phenotypic properties and gene expression of Staphylococcus aureus biofilm on commonly used food contact surfaces.<br><br>METHODS AND RESULTS: The minimum inhibitory concentration and minimum bactericidal concentration of Od-EO on S. aureus ATCC25923 were determined to be 0.5 and 1&#x2009;&#xb5;l/ml, respectively. Crystal violet staining, scanning electron microscopy (SEM), biofilm metabolic activity evaluation, and real-time PCR analysis were used to assess the anti-biofilm properties of Od-EO. The results demonstrated that Od-EO exhibited significant anti-biofilm properties against S. aureus and effectively reduced the metabolic activity of biofilm cells. Furthermore, the inhibitory effects of Od-EO on biofilm formation were more pronounced on stainless steel (SS) compared to high-density polyethylene (HDPE) surfaces. Real-time PCR analysis revealed that Od-EO downregulated the expression of biofilm-related genes (icaA, icaD, clfA, clfB, FnbA, FnbB, and hld) in S. aureus grown on SS, while the expression levels of all studied genes except hld in the biofilm formed on HDPE remained unchanged or increased.<br><br>CONCLUSIONS: One of the main anti-biofilm mechanisms of the Od-EO on the HDPE is related to the disturbance in the QS of the cells. These findings highlight the potential of Od-EO as an effective agent for controlling and inhibiting S. aureus biofilm in the food industry and its potential use in disinfectant compounds.}, }
@article {pmid39053599, year = {2024}, author = {Li, P and Luo, Y and Tian, J and Cheng, Y and Wang, S and An, X and Zheng, J and Yan, H and Duan, H and Zhang, J and Pan, Z and Chen, Y and Wang, R and Zhou, H and Wang, Z and Tan, Z and Li, X}, title = {Outdoor tubular photobioreactor microalgae-microorganisms biofilm treatment of municipal wastewater: Enhanced heterotrophic assimilation and synergistic aerobic denitrogenation.}, journal = {Bioresource technology}, volume = {408}, number = {}, pages = {131151}, doi = {10.1016/j.biortech.2024.131151}, pmid = {39053599}, issn = {1873-2976}, mesh = {*Microalgae/metabolism ; *Biofilms ; *Wastewater/microbiology ; *Photobioreactors/microbiology ; *Nitrogen/metabolism ; *Denitrification ; *Heterotrophic Processes ; Phosphorus ; Water Purification/methods ; Aerobiosis ; Carbon/metabolism/pharmacology ; Waste Disposal, Fluid/methods ; }, abstract = {This research evaluated a microalgae consortium (MC) in a pilot-scale tubular photobioreactor for municipal wastewater (MWW) treatment, compared with an aeration column photobioreactor. Transitioning from suspended MC to a microalgae-microbial biofilm (MMBF) maintained treatment performance despite increasing influent from 50 L to 150 L in a 260 L system. Carbon and nitrogen removal were effective, but phosphorus removal varied due to biofilm shading and the absence of phosphorus-accumulating organisms. High influent flow caused MMBF detachment due to shear stress. Stabilizing and re-establishing the MMBF showed that a stable phycosphere influenced microbial diversity and interactions, potentially destabilizing the MMBF. Heterotrophic nitrification-aerobic denitrification bacteria were crucial for MC equilibrium. Elevated gene expression related to nitrogen fixation, organic nitrogen metabolism, and nitrate reduction confirmed strong microalgal symbiosis, highlighting MMBF's treatment potential. This study supports the practical application of microalgae in wastewater treatment.}, }
@article {pmid39052827, year = {2024}, author = {Liu, S and Li, Y and Xu, H and Kearns, DB and Wu, Y}, title = {Active interface bulging in Bacillus subtilis swarms promotes self-assembly and biofilm formation.}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, volume = {121}, number = {31}, pages = {e2322025121}, pmid = {39052827}, issn = {1091-6490}, support = {R35 GM131783/GM/NIGMS NIH HHS/United States ; }, mesh = {*Bacillus subtilis/physiology ; *Biofilms/growth &amp; development ; }, abstract = {Microbial communities such as biofilms are commonly found at interfaces. However, it is unclear how the physical environment of interfaces may contribute to the development and behavior of surface-associated microbial communities. Combining multimode imaging, single-cell tracking, and numerical simulations, here, we found that activity-induced interface bulging promotes colony biofilm formation in Bacillus subtilis swarms presumably via segregation and enrichment of sessile cells in the bulging area. Specifically, the diffusivity of passive particles is ~50% lower inside the bulging area than elsewhere, which enables a diffusion-trapping mechanism for self-assembly and may account for the enrichment of sessile cells. We also uncovered a quasilinear relation between cell speed and surface-packing density that underlies the process of active interface bulging. Guided by the speed-density relation, we demonstrated reversible formation of liquid bulges by manipulating the speed and local density of cells with light. Over the course of development, the active bulges turned into striped biofilm structures, which eventually give rise to a large-scale ridge pattern. Our findings reveal a unique physical mechanism of biofilm formation at air-solid interface, which is pertinent to engineering living materials and directed self-assembly in active fluids.}, }
@article {pmid39052320, year = {2024}, author = {Tang, M and Yang, R and Zhuang, Z and Han, S and Sun, Y and Li, P and Fan, K and Cai, Z and Yang, Q and Yu, Z and Yang, L and Li, S}, title = {Divergent molecular strategies drive evolutionary adaptation to competitive fitness in biofilm formation.}, journal = {The ISME journal}, volume = {18}, number = {1}, pages = {}, pmid = {39052320}, issn = {1751-7370}, support = {A2022046//Medical Research Foundation of GuangDong Province/ ; NSZD2023011//Outstanding Young Researcher Program/ ; //Science and Technology Key Research Program in Nanshan District Health Care System/ ; JCYJ20210324112607020//Shenzhen Science and Technology Innovation Commission for Research and Development Projects/ ; 2023A1515110855//GuangDong Basic and Applied Basic Research Foundation/ ; 32270196//National Natural Science Foundation/ ; KQTD20200909113758004//Shenzhen Overseas High-level Talent Team/ ; }, mesh = {*Biofilms/growth &amp; development ; *Pseudomonas aeruginosa/genetics/physiology ; Genetic Fitness ; Adaptation, Physiological ; Virulence ; Mutation ; Bacteriophages/genetics/physiology ; Cyclic GMP/metabolism/analogs &amp; derivatives ; Superinfection/microbiology ; Biological Evolution ; }, abstract = {Biofilm is a group of heterogeneously structured and densely packed bacteria with limited access to nutrients and oxygen. These intrinsic features can allow a mono-species biofilm to diversify into polymorphic subpopulations, determining the overall community's adaptive capability to changing ecological niches. However, the specific biological functions underlying biofilm diversification and fitness adaptation are poorly demonstrated. Here, we launched and monitored the experimental evolution of Pseudomonas aeruginosa biofilms, finding that two divergent molecular trajectories were adopted for adaptation to higher competitive fitness in biofilm formation: one involved hijacking bacteriophage superinfection to aggressively inhibit kin competitors, whereas the other induced a subtle change in cyclic dimeric guanosine monophosphate signaling to gain a positional advantage via enhanced early biofilm adhesion. Bioinformatics analyses implicated that similar evolutionary strategies were prevalent among clinical P. aeruginosa strains, indicative of parallelism between natural and experimental evolution. Divergence in the molecular bases illustrated the adaptive values of genomic plasticity for gaining competitive fitness in biofilm formation. Finally, we demonstrated that these fitness-adaptive mutations reduced bacterial virulence. Our findings revealed how the mutations intrinsically generated from the biofilm environment influence the evolution of P. aeruginosa.}, }
@article {pmid39049919, year = {2024}, author = {Prajapati, RA and Jadeja, GC}, title = {Red dragon fruit-soy protein isolate biofilm: UV-blocking, antioxidant &amp; improved mechanical properties for sustainable food packaging.}, journal = {Journal of food science and technology}, volume = {61}, number = {9}, pages = {1686-1700}, pmid = {39049919}, issn = {0022-1155}, abstract = {UNLABELLED: In this study, an active biofilm was developed by incorporating red dragon fruit peel (RDF) extract into soy protein isolate (SPI) film matrix for sustainable food packaging. The addition of betalain-rich-RDF extract (1-7 wt%) significantly improved UV-blocking and antioxidant properties of the film compared to the control film. As wt% of RDF-extract increased, water vapor permeability, water solubility, and elongation at break decreased by 1.06 × 10[-10] g m m[-2] s[-1] Pa[-1], 34.25%, and 133.25%, respectively. On the other hand, Tensile strength increased significantly (P < 0.05) by 78.76%. FTIR results confirmed the intermolecular interaction between RDF extract and SPI through hydrogen bonding, while XRD result showed a decrease in the crystallinity degree of the film with RDF extract addition. However, no significant change in the TGA curve between extract-incorporated SPI films was observed. SEM analysis revealed that SPI B and SPI D films had a more compact and denser structure than the control film, while AFM analysis showed an increase in Ra and Rq values representing higher surface roughness of SPI D film. SPI D film also significantly (P < 0.05) decreased the weight loss and increased total soluble solids of freshly cut apples over 7-day storage period.<br><br>SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13197-024-05940-2.}, }
@article {pmid39049800, year = {2024}, author = {Aydin, A and Sudagidan, M and Abdramanov, A and Yurt, MNZ and Mamatova, Z and Ozalp, VC}, title = {Horse Meat Microbiota: Determination of Biofilm Formation and Antibiotic Resistance of Isolated Staphylococcus Spp.}, journal = {Foodborne pathogens and disease}, volume = {21}, number = {10}, pages = {643-652}, doi = {10.1089/fpd.2023.0171}, pmid = {39049800}, issn = {1556-7125}, mesh = {Horses/microbiology ; Animals ; *Biofilms/drug effects ; *Staphylococcus/drug effects/isolation &amp; purification/genetics ; *RNA, Ribosomal, 16S/genetics ; *Anti-Bacterial Agents/pharmacology ; *Microbiota ; Kazakhstan ; Meat/microbiology ; Microbial Sensitivity Tests ; High-Throughput Nucleotide Sequencing ; Food Microbiology ; Drug Resistance, Bacterial/genetics ; Drug Resistance, Multiple, Bacterial/genetics ; }, abstract = {Domestic horses could be bred for leisure activities and meat production, as is already the case in many countries. Horse meat is consumed in various countries, including Kazakhstan and Kyrgyzstan, and with the increase in this consumption, horses are registered as livestock by the Food and Agricultural Organization. In this study, horse meat microbiota of horse samples (n = 56; 32 samples from Kazakhstan and 24 samples from Kyrgyzstan) from two countries, Kazakhstan (n = 3) and Kyrgyzstan (n = 1), were investigated for the first time by next-generation sequencing and metabarcoding analysis. The results demonstrated that Firmicutes, Proteobacteria, and Actinobacteria were the dominant bacterial phyla in all samples. In addition, three (5.4%) Staphylococcus strains were isolated from the Uzynagash region, Kazakhstan. Staphylococcus strains were identified as Staphylococcus warneri, S. epidermidis, and S. pasteuri by partial 16S rRNA DNA gene Sanger sequencing. All three Staphylococcus isolates were nonbiofilm formers; only the S. pasteuri was detected as multidrug-resistant (resistant to penicillin, cefoxitin, and oxacillin). In addition, S. pasteuri was found to carry mecA, mecC, and tetK genes. This is the first study to detect potentially pathogenic Staphylococcus spp. in horse meat samples originating from Kazakhstan. In conclusion, it should be carefully considered that undercooked horse meat may pose a risk to consumers in terms of pathogens such as antibiotic-resistant Staphylococcus isolates.}, }
@article {pmid39048998, year = {2024}, author = {Pourhajibagher, M and Ghafari, HA and Bahador, A}, title = {Postbiotic mediators derived from Lactobacillus species enhance riboflavin-mediated antimicrobial photodynamic therapy for eradication of Streptococcus mutans planktonic and biofilm growth.}, journal = {BMC oral health}, volume = {24}, number = {1}, pages = {836}, pmid = {39048998}, issn = {1472-6831}, mesh = {*Biofilms/drug effects ; *Streptococcus mutans/drug effects ; *Riboflavin/pharmacology ; *Photochemotherapy/methods ; *Microbial Sensitivity Tests ; Lactobacillus/drug effects ; Photosensitizing Agents/pharmacology ; Plankton/drug effects ; Lacticaseibacillus casei/drug effects ; Anti-Bacterial Agents/pharmacology ; }, abstract = {BACKGROUND: Streptococcus mutans has been implicated as a primary causative agent of dental caries and one of its important virulence properties is an ability to form biofilm on tooth surfaces. Thus, strategies to prevent and control S. mutans biofilms are requested. The present study aimed to examine the eradication of S. mutans planktonic and biofilm cells using riboflavin (Rib)-mediated antimicrobial photodynamic therapy (aPDT) enhanced by postbiotic mediators derived from Lactobacillus species.<br><br>MATERIALS AND METHODS: Minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of Rib and postbiotic mediators were determined. The antimicrobial and anti-biofilm effects of Rib-mediated aPDT (Rib plus blue light), Rib-mediated aPDT in combination with postbiotic mediators derived from Lactobacillus casei (LC) (aPDT[+&#x2009;LC]), and Rib-mediated aPDT in combination with postbiotic mediators derived from Lactobacillus plantarum (LP) (aPDT[+&#x2009;LP]) were evaluated. The anti-virulence potential of Rib-mediated aPDT, aPDT[+&#x2009;LC], and aPDT[+&#x2009;LP] were assessed by measuring the expression of the gtfB gene using quantitative real-time polymerase chain reaction (qRT-PCR) at the highest concentrations of Rib, LC, and LP, at which the S. mutans had proliferation as the same as in the control (non-treated) group.<br><br>RESULTS: According to the results, the MIC doses of LC, LP, and Rib were 64&#xa0;&#xb5;g/mL, 128&#xa0;&#xb5;g/mL, and 128&#xa0;&#xb5;g/mL, respectively, while the MBC values of LC, LP, and Rib were 128&#xa0;&#xb5;g/mL, 256&#xa0;&#xb5;g/mL, and 256&#xa0;&#xb5;g/mL, respectively. Rib-mediated aPDT, aPDT[+&#x2009;LP], and aPDT[+&#x2009;LC] showed a significant reduction in Log10 CFU/mL of S. mutans compared to the control group (4.2, 4.9, and 5.2 Log10 CFU/mL, respectively; all P&#x2009;<&#x2009;0.05). The most destruction of S. mutans biofilms was observed after treatment with aPDT[+&#x2009;LC] followed by aPDT[+&#x2009;LP] and Rib-mediated aPDT (77.5%, 73.3%, and 67.6%, respectively; all P&#x2009;<&#x2009;0.05). The concentrations of 31.2&#xa0;&#xb5;g/mL, 62.5&#xa0;&#xb5;g/mL, and 62.5&#xa0;&#xb5;g/mL were considered as the highest concentrations of LC, LP, and Rib, respectively, at which S. mutans replicates as same as the control group and were used for gtfB gene expression assay using qRT-PCR during Rib-mediated aPDT, aPDT[+&#x2009;LP], and aPDT[+&#x2009;LC] treatments. Gene expression results revealed that aPDT[+&#x2009;LP] and aPDT[+&#x2009;LC] could decrease the gene expression level of gtfB by 6.3- and 5.7-fold, respectively (P&#x2009;<&#x2009;0.05), while only 5.1-fold reduction was observed after Rib-mediated aPDT (P&#x2009;<&#x2009;0.05).<br><br>CONCLUSION: Our findings indicate that aPDT[+&#x2009;LP] and aPDT[+&#x2009;LC] hold promise for use as a treatment to combat S. mutans planktonic and biofilms growth as well as anti-virulence as a preventive strategy to inhibit biofilms development via reduction of gtfB gene expression.}, }
@article {pmid39047804, year = {2024}, author = {Haque, A and Chowdhury, A and Islam Bhuiyan, MN and Bhowmik, B and Afrin, S and Sarkar, R and Haque, MM}, title = {Molecular characterization, antibiotic resistant pattern and biofilm forming potentiality of bacterial community associated with Ompok pabda fish farming in southwestern Bangladesh.}, journal = {Microbial pathogenesis}, volume = {194}, number = {}, pages = {106818}, doi = {10.1016/j.micpath.2024.106818}, pmid = {39047804}, issn = {1096-1208}, mesh = {*Biofilms/growth &amp; development/drug effects ; Animals ; *Anti-Bacterial Agents/pharmacology ; *Aquaculture ; *Bacteria/genetics/drug effects/classification/isolation &amp; purification ; *Microbial Sensitivity Tests ; Bangladesh ; Drug Resistance, Bacterial/genetics ; Fish Diseases/microbiology ; Fishes/microbiology ; Gills/microbiology ; Water Microbiology ; }, abstract = {Ompok pabda is gaining popularity in the aquaculture industry due to its increasing demand; however research on microbial diversity and antibiotic susceptibility remains limited. The present study was designed to identify the bacterial pathogens commonly found in the pabda farming system with their biofilm forming potential and antibiotic susceptibility. Different bacterial strains were isolated from water, sediments and gut, gill of pabda fish and the isolates were identified based on their morphological traits, biochemical and molecular analysis. Antibiotic susceptibilities, antibiotic resistance gene determination and biofilm formation capabilities were evaluated by disc diffusion method, PCR amplification and Microtiter plate (MTP) assay, respectively. The respective isolates of gill and gut of pabda aquaculture and their environments were: Exiguobacterium spp. (25 %), Enterococcus spp. (20 %), Bacillus spp. (10 %), Acinetobacter spp. (10 %), Enterobacter spp. (10 %), Aeromonas spp. (10 %), Lactococcus spp. (5 %), Klebsiella spp. (5 %) and Kurthia spp. (5 %). Antibiotic resistance frequencies were found to be relatively high, especially for trimethoprim (95 %), sulfafurazole (75 %), ampicillin (60 %), amoxicillin-clavulanic acid (55 %), and cephradine (50 %). 30 % isolates were categorized as DR bacteria followed by 30 % isolates were MDR bacteria and 40 % were classified as XDR bacteria. Moreover, 4 antibiotic resistant genes were detected with sul1 (30 %), dfrA1 (10 %), tetC (40 %), and qnrA (5 %) of isolates. Based on the microtiter plate method, 20 %, 25 %, and 30 % of isolates were found to produce strong, moderate, and weak biofilms, respectively. The findings suggest that biofilm forming bacterial strains found in O. pabda fish farm may be a potential source of numerous antibiotic-resistant bacteria. The study sheds new light on antibiotic resistance genes, which are typically inherited by bacteria and play an important role in developing effective treatments or control strategies.}, }
@article {pmid39046262, year = {2024}, author = {Sheikhy, M and Karbasizade, V and Ghanadian, M and Fazeli, H}, title = {Evaluation of chlorogenic acid and carnosol for anti-efflux pump and anti-biofilm activities against extensively drug-resistant strains of Staphylococcus aureus and Pseudomonas aeruginosa.}, journal = {Microbiology spectrum}, volume = {12}, number = {9}, pages = {e0393423}, pmid = {39046262}, issn = {2165-0497}, support = {340106//Isfahan University of Medical Sciences (IUMS)/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Pseudomonas aeruginosa/drug effects ; *Staphylococcus aureus/drug effects/physiology ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; Humans ; *Drug Resistance, Multiple, Bacterial/drug effects ; *Abietanes/pharmacology ; *Chlorogenic Acid/pharmacology/chemistry ; Staphylococcal Infections/microbiology ; Drug Synergism ; Pseudomonas Infections/microbiology ; Cross Infection/microbiology ; }, abstract = {UNLABELLED: Efflux pumps and biofilm play significant roles in bacterial antibiotic resistance. This study investigates the potential of chlorogenic acid (CGA) and carnosol (CL), as phenolic and diterpene compounds, respectively, for their inhibitory effects on efflux pumps. Among the 12 multidrug-resistant (MDR) strains of Staphylococcus aureus and Pseudomonas aeruginosa isolated from nosocomial skin infections, eight strains were identified as extensively drug resistant (XDR) using the disc diffusion method. The presence of efflux pumps in MDR strains of S. aureus and P. aeruginosa was screened using carbonyl cyanide-m-chlorophenylhydrazone. Between the 12 MDR strains of S. aureus and P. aeruginosa, 80% (4 out of 5) of the S. aureus strains and 85.7% (6 out of 7) of the P. aeruginosa strains exhibited active efflux pumps associated with gentamicin resistance. The checkerboard assay results, in combination with gentamicin, demonstrated that CGA exhibited a reduction in the minimum inhibitory concentration (MIC) for XDR S. aureus strain. Similarly, CL showed a synergistic effect and reduced the MIC for both XDR strains of S. aureus and P. aeruginosa. Flow cytometry was used to examine efflux pump activity at sub-MIC concentrations of 1/8, 1/4, and 1/2 MIC in comparison to the control. In XDR S. aureus, CGA demonstrated 39%, 70%, and 19% inhibition, while CL exhibited 74%, 73.5%, and 62% suppression. In XDR P. aeruginosa, CL exhibited inhibition rates of 25%, 10%, and 15%. The inhibition of biofilm formation was assessed using the microtiter plate method, resulting in successful inhibition of biofilm formation. Finally, the MTT assay was conducted, and it confirmed minimal cytotoxicity. Given the significant reduction in efflux pump activity and biofilm formation observed with CGA and CL in this study, these compounds can be considered as potential inhibitors of efflux pumps and biofilm formation, offering potential strategies to overcome antimicrobial resistance.<br><br>IMPORTANCE: In summary, CGA and CL demonstrated promising potentiating antimicrobial effects against XDR strains of Staphylococcus aureus and Pseudomonas aeruginosa, suggesting their probably potential as candidates for addressing nosocomial pathogens. They exhibited significant suppression of efflux pump activity, indicating a possible successful inhibition of this mechanism. Moreover, all substances effectively inhibited biofilm formation, while showing minimal cytotoxicity. However, further advancement to clinical trials is needed to evaluate the feasibility of utilizing CGA and CL for reversing bacterial XDR efflux and determining their efficacy against biofilms. These trials will provide valuable insights into the practical applications of these compounds in combating drug-resistant infections.}, }
@article {pmid39046242, year = {2024}, author = {Xue, J and Li, S and Wang, L and Zhao, Y and Zhang, L and Zheng, Y and Zhang, W and Chen, Z and Jiang, T and Sun, Y}, title = {Enhanced fatty acid biosynthesis by Sigma28 in stringent responses contributes to multidrug resistance and biofilm formation in Helicobacter pylori.}, journal = {Antimicrobial agents and chemotherapy}, volume = {68}, number = {9}, pages = {e0085024}, pmid = {39046242}, issn = {1098-6596}, support = {82172313//MOST | National Natural Science Foundation of China (NSFC)/ ; 2021GXGC011305//Major Scientific and Technological Innovation Project of Shandong Province ()/ ; no. ZK (2022) 341//| Science and Technology Program of Guizhou Province ()/ ; }, mesh = {*Anti-Bacterial Agents/pharmacology ; *Bacterial Proteins/genetics/metabolism ; *Biofilms/drug effects/growth &amp; development ; *Drug Resistance, Multiple, Bacterial/genetics ; *Fatty Acids/biosynthesis/metabolism ; Gene Expression Regulation, Bacterial/drug effects ; *Helicobacter pylori/drug effects/genetics ; Microbial Sensitivity Tests ; Operon ; Sigma Factor/genetics/metabolism ; }, abstract = {The metabolic state of bacteria significantly contributes to their resistance to antibiotics; however, the specific metabolic mechanisms conferring antimicrobial resistance in Helicobacter pylori remain largely understudied. Employing transcriptomic and non-targeted metabolomics, we characterized the metabolic reprogramming of H. pylori when challenged with antibiotic agents. We observed a notable increase in both genetic and key proteomic components involved in fatty acid biosynthesis. Inhibition of this pathway significantly enhanced the antibiotic susceptibility of the sensitive and multidrug-resistant H. pylori strains while also disrupting their biofilm-forming capacities. Further analysis revealed that antibiotic treatment induced a stringent response, triggering the expression of the hp0560-hp0557 operon regulated by Sigma28 (σ[28]). This activation in turn stimulated the fatty acid biosynthetic pathway, thereby enhancing the antibiotic tolerance of H. pylori. Our findings reveal a novel adaptive strategy employed by H. pylori to withstand antibiotic stress.}, }
@article {pmid39046207, year = {2024}, author = {Keskin, BH and Şahin, &#x130; and Kahraman, G and Duran, PK and Dülger, G and Durmuş, MA and Ceylan, AN and Çalışkan, E and Öksüz, &#x15e;}, title = {[Investigation of Biofilm Formation, Anti-Quorum Sensing Activity and Antimicrobial Resistance in Corynebacterium Species Isolated from Clinical Samples].}, journal = {Mikrobiyoloji bulteni}, volume = {58}, number = {3}, pages = {239-258}, doi = {10.5578/mb.20249704}, pmid = {39046207}, issn = {0374-9096}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Corynebacterium/drug effects/isolation &amp; purification/growth &amp; development ; Humans ; *Anti-Bacterial Agents/pharmacology ; *Corynebacterium Infections/microbiology ; *Microbial Sensitivity Tests ; *Quorum Sensing/drug effects ; Drug Resistance, Bacterial ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ; Indoles/pharmacology ; }, abstract = {An increasing number of different clinical infections caused by Corynebacteria have been reported in the last decade. The aim of this study was to evaluate the antibiotic resistance rates, biofilm formation capacities and to investigate the ''anti-quorum-sensing (anti-QS)'' activities of corynebacteria, which were divided into three groups according to the type of growth in culture (pure, with another pathogenic bacterium and polymicrobial growth). In total 240 Corynebacterium spp. isolates from different clinical specimens sent to the medical microbiology laboratories of Düzce University Faculty of Medicine Hospital and Başakşehir Çam and Sakura City Hospital between June 2021 and June 2022 were classified into three groups: pure, isolated with another pathogen and polymicrobial, according to their growth patterns in culture. Bacteria were identified by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) Biotyper (Bruker, Germany) at an external centre. Antibiotic susceptibilities were determined by disc diffusion method and for vancomycin broth microdilution method was used. Results were interpreted according to EUCAST recommendations. The biofilm-forming properties of the isolates were determined quantitatively. Bioactive components of 17 isolates with strong biofilm formation were extracted and anti-QS activity was determined by agar diffusion method using Chromobacterium violaceum ATCC 12472 strain and then violacein pigment production was measured quantitatively. Of the 240 Corynebacterium spp. isolates, 138 (58%) were pure, 52 (22%) were isolated with another pathogen and 50 (20%) were part of a polymicrobial infection. Of the isolates, 140 were identified as C.striatum, 34 as C.amycolatum and 24 as Corynebacterium afermentans. When the antibiotic resistance rates of the Corynebacterium isolates were analysed according to the groups, the resistance rates to rifampicin and tetracycline antibiotics were found to be statistically significantly lower in the polymicrobial group than in the other groups. The resistance rates to penicillin, clindamycin, ciprofloxacin, moxifloxacin, rifampicin, tetracycline and linezolid were 96.7%, 88.3%, 86.3%, 73.8%, 62.5%, 59.2% and 0.8%, respectively. While all isolates were susceptible to vancomycin, linezolid resistance was detected in two C.afermentans isolates. When the biofilm formation ability was analysed, it was observed that 87 (36.3%) isolates formed biofilm. The biofilm formation rate of the isolates in the polymicrobial growth group was lower than the other two groups. The anti-QS activity of 17 isolates with strong biofilm formation was investigated and none of the Corynebacterium extracts tested were found to have anti-QS activity (inhibition of violacein pigment production without inhibiting bacterial growth) in the QS study with C.violaceum, whereas five isolate extracts had antibacterial activity (inhibition of bacterial growth). Four of the bacterial extracts with antimicrobial activity belonged to C.amycolatum and one to C.afermentans. In conclusion, when both antibiotic resistance rates and biofilm formation rates were analysed, the corynebacteria growing in culture with another pathogen showed similar characteristics to the corynebacteria growing as a pure culture. Therefore, it was thought that corynebacteria growing with another pathogen should not be ignored. In addition, the antimicrobial effects of some corynebacterial extracts suggested that more QS studies should be carried out with microbiota bacteria.}, }
@article {pmid39046206, year = {2024}, author = {Öztaş Gülmüş, E and Akçelik, N and Özdemir, C and Akçelik, M}, title = {[Effect of Quorum Sensing Systems on Biofilm Formation and Virulence in Salmonella].}, journal = {Mikrobiyoloji bulteni}, volume = {58}, number = {3}, pages = {225-238}, doi = {10.5578/mb.20240038}, pmid = {39046206}, issn = {0374-9096}, mesh = {*Quorum Sensing ; *Biofilms/growth &amp; development ; *Carbon-Sulfur Lyases/genetics ; Virulence ; *Bacterial Proteins/genetics/metabolism ; *Homoserine/analogs &amp; derivatives ; *Gene Expression Regulation, Bacterial ; Mutation ; Virulence Factors/genetics ; 4-Butyrolactone/analogs &amp; derivatives/metabolism ; Animals ; Salmonella/pathogenicity/genetics ; }, abstract = {In recent years, as the paradigm of communication between cells has been clarified, the ability of bacteria to change their gene expression patterns in response to various extracellular signals has attracted great interest. In particular, intracellular and intercellular communication between bacterial populations, called quorum sensing (QS), is essential for coordinating physiological and genetic activities. QS studies are critical, particularly in elucidating the regulatory mechanisms of infectious processes in food-borne pathogens. Elucidating the QS mechanisms in Salmonella is effective in silencing the virulence factors in the fight against this bacterium. The aims of this study were; to create luxS gene mutants that play a vital role in the QS activity of Salmonella and to determine the effect of this mutation on the expression of virulence genes in the bacteria and to determine the impact of synthetic N-hexanoyl-homoserine lactone (C6HSL) on biofilm formation and AI-2 signaling pathway of Salmonella wild strain and luxS gene mutants. luxS gene mutants were constructed by recombining the gene region with the chloramphenicol gene cassette based on homologous region recombination. In the luxS mutants obtained in this way, the expression of eight different virulence genes (hilA, invA, inv, glgC, fimF, fliF, lpfA, gyrA), which have essential roles in Salmonella pathogenicity, was determined by quantitative real-time reverse transcriptase polymerase chain reaction (rRT-qPCR) method and compared with natural strains. As a result of these studies, it was determined that the expression of each gene examined was significantly reduced in luxS mutant strains. The relative AI-2 activities of Salmonella strains were analyzed depending on time. It was determined that the highest activity occurred at the fourth hour and the AI-2 activities of luxS mutants were reduced compared to the wild strain. Finally, it was determined that C6HSL increased the biofilm activity of Salmonella Typhimurium DMC4, SL1344 wild strains, and mutants, mainly at the 72nd hour. In conclusion, our results proved that C6HSL stimulated QS communication in all strains and increased biofilm of Salmonella formation and autoinducer activity. This situation determines that Salmonella responds to external signals by using QS systems. In addition, this research contributed to provide additional information on interspecies communication mechanisms to develop strategies to prevent biofilm formation of this pathogen.}, }
@article {pmid39045150, year = {2024}, author = {Breivik, A and Mulic, A and Sehic, A and Valen, HR and Kopperud, S and Stein, L and Khan, Q}, title = {Accumulation and removal of Streptococcus mutans biofilm on enamel and root surfaces in vitro.}, journal = {Biomaterial investigations in dentistry}, volume = {11}, number = {}, pages = {41059}, pmid = {39045150}, issn = {2641-5275}, abstract = {OBJECTIVE: This study aimed to quantitatively investigate the accumulation of Streptococcus mutans biofilm on enamel and root surfaces and assess the amount of biofilm removal using (1) experimental toothpaste and (2) water, in a closed system of flow chamber.<br><br>METHODS: Eight sound premolars were embedded in epoxy resin and polished with silicon carbide grinding papers to display enamel and root surfaces. To mimic biofilm, cultures of Streptococcus mutans were prepared and grown on the tooth surfaces over night before they were exposed to either 2 liters of Milli Q water or 2 liters of 40% experimental toothpaste in the flow chamber. The amount of biofilm was measured and quantified in Fluorescence microscopy. Mean fluorescence values were recorded and analysed using Microsoft&#xae; Excel&#xae; (MS Excel 2016).<br><br>RESULTS: The ability to grow biofilm was equally present at both the enamel and root surfaces. The use of water and 40% experimental toothpaste showed a significant reduction of areas covered with biofilm on both enamel and root dentin in comparison to untreated surfaces (p < 0.01). Significantly more biofilm was removed from enamel compared to root surfaces when treated with either water and toothpaste (p < 0.01). Slightly less biofilm was removed by the use of water compared to toothpaste on both enamel and root dentin surfaces, although the differences were not statistically significant.<br><br>CONCLUSION: The results indicate that less biofilm is removed from the root surfaces than enamel by the use of water and 40% experimental toothpaste in flow chamber. Assessing oral biofilm accumulation and monitoring biofilm formation on enamel and root dentin surfaces give oral health professionals important directions that could strenghten the significance of dental caries prevention. Improving older individuals' oral hygiene practices should therefore be considered an important measure to prevent root caries.}, }
@article {pmid39044574, year = {2024}, author = {Wang, Z and Chen, J and You, Z and Liu, X and Zhang, J}, title = {[Advances in mechanisms of biofilm formation and drug resistance of Staphylococcus aureus].}, journal = {Sheng wu gong cheng xue bao = Chinese journal of biotechnology}, volume = {40}, number = {7}, pages = {2038-2051}, doi = {10.13345/j.cjb.230803}, pmid = {39044574}, issn = {1872-2075}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Staphylococcus aureus/drug effects/physiology ; *Anti-Bacterial Agents/pharmacology ; Humans ; Staphylococcal Infections/microbiology ; Drug Resistance, Multiple, Bacterial ; Drug Resistance, Bacterial ; }, abstract = {Staphylococcus aureus is a common pathogenic bacterium. However, due to the abuse of antibiotics, multiple drug-resistant S. aureus (DR S. aureus) has emerged in a large number, which seriously threatens human health. DR S. aureus usually forms biofilms by attaching on contact surfaces and secreting macromolecules including polysaccharides, proteins, and lipids, thus encasing themselves in a self-generated polymeric matrix. A biofilm provides an efficacious barrier that protects bacteria from detrimental environmental factors. Simultaneously, it protects DR S. aureus from the host immune system and attenuates the penetration and killing effects of drugs, serving as a key structure for the development of drug resistance. Therefore, gaining an in-depth understanding of the DR S. aureus biofilm is crucial for treating related infectious diseases. In this paper, we summarize recent research progress in the biofilm formation mechanism, drug resistance mechanism, and measures for inhibition and clearance of DR S. aureus and provide an outlook on the future research directions.}, }
@article {pmid39042175, year = {2024}, author = {Kirchhoff, L and Arweiler-Harbeck, D and Meyer, M and Buer, J and Lang, S and Steinmann, J and Bertram, R and Deuss, E and Höing, B}, title = {Bacterial biofilm formation on headpieces of Cochlear implants.}, journal = {European archives of oto-rhino-laryngology : official journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) : affiliated with the German Society for Oto-Rhino-Laryngology - Head and Neck Surgery}, volume = {281}, number = {12}, pages = {6261-6266}, pmid = {39042175}, issn = {1434-4726}, mesh = {*Biofilms/growth &amp; development ; *Pseudomonas aeruginosa ; *Staphylococcus aureus ; *Cochlear Implants/microbiology ; Humans ; *Prosthesis-Related Infections/microbiology ; Equipment Contamination ; }, abstract = {INTRODUCTION: Bacterial biofilm formation on medical devices, such as Cochlear implants (CI), can lead to chronic infections. Not only the inner parts of the implant but also the externally located headpiece might be associated with prolonged superficial skin eczema resulting in the inability of wearing the headpiece. In this study, the surface of three CI headpieces from different manufacturers were examined for bacterial biofilm formation.<br><br>MATERIALS AND METHODS: Two bacterial species associated with implant-related infections were tested: Pseudomonas aeruginosa (ATCC9027) and Staphylococcus aureus (ATCC6538). Biofilms were formed over 24&#xa0;h in tryptic soy broth at 36&#xa0;&#xb0;C. Biofilm formation was detected in form of biomass measurement by crystal violet staining. CI headpiece dummies of three manufacturers were used.<br><br>RESULTS: Both tested bacterial species formed biofilms on the examined CI headpiece-surfaces in a species-dependent manner with higher biofilm formation of P. aeruginosa. For both, S. aureus and P. aeruginosa, biofilm formation on the CI components was comparable to a polystyrene control surface. Between the three manufacturers, no significant difference in biofilm formation was found.<br><br>DISCUSSION: The tested bacteria displayed biofilm formation on the CI headpieces in a species-specific manner with higher amount of biofilm formed by P. aeruginosa. The biofilm formation was comparable between the manufacturers. In this study, an enhanced biofilm formation on CI headpieces could not be demonstrated. These in vitro tests suggest a minor role of bacterial biofilm on the CI headpiece in skin infections under the CI headpiece.}, }
@article {pmid39040541, year = {2024}, author = {Pan, Z and Dai, C and Li, W}, title = {Material-based treatment strategies against intraosseous implant biofilm infection.}, journal = {Biochemistry and biophysics reports}, volume = {39}, number = {}, pages = {101764}, pmid = {39040541}, issn = {2405-5808}, abstract = {Implant-associated infections present a significant clinical obstacle for orthopedic practitioners, with bacterial biofilm formation serving as a pivotal factor in the initiation, progression, and management of such infections. Conventional approaches have proven inadequate in fully eradicating biofilm-related infections. Consequently, novel material-based therapeutic strategies have been developed, encompassing the utilization of antimicrobial agents, delivery vehicles, and synergistic antibacterial systems. In this review, we provide a succinct overview of recent advancements in anti-biofilm strategies, with the aim of offering insights that may aid in the treatment of intraosseous implant infections.}, }
@article {pmid39040382, year = {2024}, author = {Chandraraj, SS and Suyambulingam, I and Edayadulla, N and Divakaran, D and Singh, MK and Sanjay, MR and Siengchin, S}, title = {Characterization of Calotropis gigantiea plant leaves biomass-based bioplasticizers for biofilm applications.}, journal = {Heliyon}, volume = {10}, number = {13}, pages = {e33641}, pmid = {39040382}, issn = {2405-8440}, abstract = {The present surge in environmental consciousness has pushed for the use of biodegradable plasticizers, which are sustainable and abundant in plant resources. As a result of their biocompatibility and biodegradability, Calotropis gigantiea leaf plasticizers (CLP) serve as viable alternatives to chemical plasticizers. First time, the natural plasticizers from the Calotropis leaves were extracted for this study using a suitable chemical approach that was also environmentally friendly. The XRD results showed a reduced crystallinity index of 20.2 % and a crystalline size of 5.3 nm, respectively. TGA study revealed that the CLP has good thermal stability (244 °C). Through FT-IR study, the existence of organic compounds in CLP can be investigated by key functional groups such as alcohol, amine, amide, hydrocarbon, alkene, aromatic, etc. Further the presence of alcoholic, amino, and carboxyl constituents was confirmed by UV investigation. SEM, EDAX analysis, and AFM are used to examine the surface morphology of the isolated plasticizer. SEM pictures reveal rough surfaces on the CLP surface pores, which makes them suitable for plasticizing new bioplastics with improved mechanical properties. Poly (butylene adipate-co-terephthalate) (PBAT), a biodegradable polymer matrix, was used to investigate the plasticization impact after the macromolecules were characterised. The biofilm PBAT/CLP had a thickness of 0.8 mm. In addition, the reinforcement interface was examined using scanning electron microscopy. When CLP is loaded differently in PBAT, the tensile strength and young modulus change from 15.30 to 24.60 MPa and from 137 to 168 MPa, respectively. CLP-reinforced films demonstrated better surface compatibility and enhanced flexibility at a loading of 2 % when compared to pure PBAT films. Considering several documented characteristics, CLP may prove to be an excellent plasticizer for resolving environmental issues in the future.}, }
@article {pmid39039267, year = {2024}, author = {Silva, AR and Melo, LF and Keevil, CW and Pereira, A}, title = {Legionella colonization and 3D spatial location within a Pseudomonas biofilm.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {16781}, pmid = {39039267}, issn = {2045-2322}, support = {LEPABE//Funda&#xe7;&#xe3;o para a Ci&#xea;ncia e a Tecnologia/ ; }, mesh = {*Biofilms/growth &amp; development ; *Legionella pneumophila/physiology ; *Pseudomonas fluorescens/physiology ; Legionella/physiology ; Microscopy, Confocal ; Tomography, Optical Coherence ; }, abstract = {Biofilms are known to be critical for Legionella settlement in engineered water systems and are often associated with Legionnaire's Disease events. One of the key features of biofilms is their heterogeneous three-dimensional structure which supports the establishment of microbial interactions and confers protection to microorganisms. This work addresses the impact of Legionella pneumophila colonization of a Pseudomonas fluorescens biofilm, as information about the interactions between Legionella and biofilm structures is scarce. It combines a set of meso- and microscale biofilm analyses (Optical Coherence Tomography, Episcopic Differential Interference Contrast coupled with Epifluorescence Microscopy and Confocal Laser Scanning Microscopy) with PNA-FISH labelled L. pneumophila to tackle the following questions: (a) does the biofilm structure change upon L. pneumophila biofilm colonization?; (b) what happens to L. pneumophila within the biofilm over time and (c) where is L. pneumophila preferentially located within the biofilm? Results showed that P. fluorescens structure did not significantly change upon L. pneumophila colonization, indicating the competitive advantage of the first colonizer. Imaging of PNA-labelled L. pneumophila showed that compared to standard culture recovery it colonized to a greater extent the 3-day-old P. fluorescens biofilms, presumably entering in VBNC state by the end of the experiment. L. pneumophila was mostly located in the bottom regions of the biofilm, which is consistent with the physiological requirements of both bacteria and confers enhanced Legionella protection against external aggressions. The present study provides an expedited methodological approach to address specific systematic laboratory studies concerning the interactions between L. pneumophila and biofilm structure that can provide, in the future, insights for public health Legionella management of water systems.}, }
@article {pmid39038400, year = {2024}, author = {Gao, SC and Fan, XX and Zhang, Z and Li, RT and Zhang, Y and Gao, TP and Liu, Y}, title = {A dual-function mixed-culture biofilm for sulfadiazine removal and electricity production using bio-electrochemical system.}, journal = {Biosensors &amp; bioelectronics}, volume = {263}, number = {}, pages = {116552}, doi = {10.1016/j.bios.2024.116552}, pmid = {39038400}, issn = {1873-4235}, mesh = {*Biofilms ; *Geobacter/metabolism/physiology/isolation &amp; purification ; *Sulfadiazine ; *Bioelectric Energy Sources/microbiology ; Electricity ; Biosensing Techniques ; Biodegradation, Environmental ; Electrochemical Techniques/methods ; }, abstract = {Sulfadiazine (SDZ) is frequently detected in environmental samples, arousing much concern due to its toxicity and hard degradation. This study investigated the electricity generation capabilities, SDZ removal and microbial communities of a highly efficient mixed-culture system using repeated transfer enrichments in a bio-electrochemical system. The mixed-culture biofilm (S160-T2) produced a remarkable current density of 954.12 ± 15.08 μA cm[-2] with 160 mg/L SDZ, which was 32.9 and 1.8 times higher than that of Geobacter sulfurreducens PCA with 40 mg/L SDZ and without additional SDZ, respectively. Especially, the impressive SDZ removal rate of 98.76 ± 0.79% was achieved within 96 h using the further acclimatized mixed-culture. The removal efficiency of this mixed-culture for SDZ through the bio-electrochemical system was 1.1 times higher than that using simple anaerobic biodegradation. Furthermore, the current density and removal efficiency in this system gradually decreased with increasing SDZ concentrations from 0 to 800 mg/L. In addition, community diversity data demonstrated that the dominant genera, Geobacter and Escherichia-Shigella, were enriched in mixed-culture biofilm, which might be responsible for the current production and SDZ removal. This work confirmed the important roles of acclimatized microbial consortia and co-substrates in the simultaneous removal of SDZ and electricity generation in an electrochemical system.}, }
@article {pmid39037897, year = {2024}, author = {Zermeño-Pérez, D and Chouirfa, H and Rodriguez, BJ and Dürig, T and Duffy, P and Cróinín, T&#xd3;}, title = {Bioresorbable Polyester Coatings with Antifouling and Antimicrobial Properties for Prevention of Biofilm Formation in Early Stage Infections on Ti6Al4V Hard-Tissue Implants.}, journal = {ACS applied bio materials}, volume = {7}, number = {8}, pages = {5728-5739}, pmid = {39037897}, issn = {2576-6422}, mesh = {*Biofilms/drug effects ; *Titanium/chemistry/pharmacology ; *Alloys/chemistry/pharmacology ; *Polyesters/chemistry/pharmacology ; *Materials Testing ; *Coated Materials, Biocompatible/chemistry/pharmacology ; *Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; *Staphylococcus aureus/drug effects ; Microbial Sensitivity Tests ; Humans ; Particle Size ; Polyethylene Glycols/chemistry/pharmacology ; Surface Properties ; Prostheses and Implants ; }, abstract = {Implants made from titanium are used as prostheses because of their biocompatibility and their mechanical properties close to those of human bone. However, the risk of bacterial infection is always a major concern during surgery, and the development of biofilm can make these infections difficult to treat. A promising strategy to mitigate against bacterial infections is the use of antifouling and antimicrobial coatings, where bioresorbable polymers can play an important role due to their controlled degradability and sustained drug release, as well as excellent biocompatibility. In the present study, poly(d,l-lactide) (PDLLA) and poly[d,l-lactide-co-methyl ether poly(ethylene glycol)] (PDLLA-PEG) were studied, varying the PEG content (20-40% w/w) to analyze the effectiveness of PEG as an antifouling molecule. In addition, silver sulfadiazine (AgSD) was used as an additional antimicrobial agent with a concentration ≤5% w/w and incorporated into the PEGylated polymers to create a polymer with both antifouling and antimicrobial properties. Polymers synthesized were applied using spin coating to obtain homogeneous coatings to protect samples made from titanium/aluminum/vanadium (Ti6Al4V). The polymer coatings had a smoothing effect in comparison to that of the uncoated material, decreasing the contact area available for bacterial colonization. It was also noted that PEG addition into the polymeric chain developed amphiphilic materials with a decrease in contact angle from the most hydrophobic (Ti6Al4V) to the most hydrophilic PDLLA-PEG (60/40), highlighting the increase in water uptake contributing to the hydration layer formation, which confers the antifouling effect on the coating. This study demonstrated that the addition of PEG above 20% w/w and AgSD above 1% w/v into the formulation was able to decrease bacterial adherence against clinically relevant biofilm former strains Staphylococcus aureus and Pseudomonas aeruginosa.}, }
@article {pmid39037809, year = {2024}, author = {Aydın, E and Kocaaga, M and Temel, A}, title = {Association of antibiotic resistance and biofilm formation in Escherichia coli ST131/O25b.}, journal = {Acta microbiologica et immunologica Hungarica}, volume = {71}, number = {3}, pages = {197-205}, doi = {10.1556/030.2024.02275}, pmid = {39037809}, issn = {1588-2640}, mesh = {*Biofilms/drug effects/growth &amp; development ; Humans ; *Escherichia coli Infections/microbiology ; *Anti-Bacterial Agents/pharmacology ; *Virulence Factors/genetics ; *Uropathogenic Escherichia coli/drug effects/genetics/physiology/isolation &amp; purification ; Female ; Male ; Adult ; Middle Aged ; Microbial Sensitivity Tests ; Aged ; beta-Lactamases/genetics ; Young Adult ; Urinary Tract Infections/microbiology ; Adolescent ; Child ; Drug Resistance, Bacterial/genetics ; Aged, 80 and over ; Drug Resistance, Multiple, Bacterial/genetics ; Escherichia coli Proteins/genetics/metabolism ; Escherichia coli/genetics/drug effects/physiology ; }, abstract = {Urinary tract infections are becoming difficult to treat every year due to antibiotic resistance. Uropathogenic Escherichia coli (UPEC) isolates pose a threat with a combined expression of multidrug-resistance and biofilm formation. ST131 clone is a high-risk pandemic clone due to its strong association with antimicrobial resistance, which has been reported frequently in recent years. This study aims to define risk factors, clinical outcomes, and bacterial genetics associated with ST131/O25b UPEC. In this study, antibiotic susceptibility and species-level identification of 61 clinical E. coli strains were determined by automated systems. Detection of extended-spectrum beta-lactamases was assessed by double-disk synergy test. Biofilm formation was quantified by spectrophotometric method. Virulence genes (iutA, sfa cnf-1, iroN, afa, papA, fimA), antibiotic resistance genes (blaCTX-M, blaTEM, blaSHV, blaOXA, qnrA, qnrB, qnrS, ant(2')-Ia, ant(3)-Ia, aac(3)-IIa, mcr-1, mcr-2, mcr-3, mcr-4) were investigated by PCR. The following beta-lactamase genes were identified, blaTEM (n = 53, 86.8%), blaCTX-M (n = 59, 96.7%), blaSHV (n = 47, 77.0%), and blaOXA-1 (n = 27, 44.2%). Our data revealed that 93.4% of (57/61) E. coli isolates were biofilm-producers. O25pabBspe and trpA2 were investigated for the presence of ST131/O25b clone. Among multidrug resistant isolates, co-existence of O25pabBspe and trpA2 was detected in 29 isolates (47.5%). The fimH30 and H30Rx subclones were detected in four isolates that are strong biofilm-producers. These results suggest that clinical E. coli strains may become reservoirs of virulence and antibiotic resistance genes. This study demonstrates a significant difference in biofilm formation between E. coli ST131 and non-ST131 isolates. Moreover, 86.21% (n = 25) of ST131 isolates produced strong to moderate biofilms, while only 43.75% (n = 14) of non-ST131 isolates showed the ability to form strong biofilms. Presence of iutA and fimA genes in the majority of ST131 strains showed an important role in biofilm formation. These findings suggest application of iutA and fimA gene suppressors in treatment of infections caused by biofilm-producing drug-resistant ST131 strains.}, }
@article {pmid39037271, year = {2024}, author = {Mookherjee, A and Mitra, M and Sason, G and Jose, PA and Martinenko, M and Pietrokovski, S and Jurkevitch, E}, title = {Flagellar stator genes control a trophic shift from obligate to facultative predation and biofilm formation in a bacterial predator.}, journal = {mBio}, volume = {15}, number = {8}, pages = {e0071524}, pmid = {39037271}, issn = {2150-7511}, support = {361/22//Israel Science Foundation (ISF)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Flagella/genetics/physiology ; *Bacterial Proteins/genetics/metabolism ; *Bdellovibrio bacteriovorus/genetics/physiology ; Mutation ; Gene Expression Regulation, Bacterial ; Cyclic GMP/analogs &amp; derivatives/metabolism ; }, abstract = {UNLABELLED: The bacterial predator Bdellovibrio bacteriovorus is considered to be obligatorily prey (host)-dependent (H-D), and thus unable to form biofilms. However, spontaneous host-independent (H-I) variants grow axenically and can form robust biofilms. A screen of 350 H-I mutants revealed that single mutations in stator genes fliL or motA were sufficient to generate flagellar motility-defective H-I strains able to adhere to surfaces but unable to develop biofilms. The variants showed large transcriptional shifts in genes related to flagella, prey-invasion, and cyclic-di-GMP (CdG), as well as large changes in CdG cellular concentration relative to the H-D parent. The introduction of the parental fliL allele resulted in a full reversion to the H-D phenotype, but we propose that specific interactions between stator proteins prevented functional complementation by fliL paralogs. In contrast, specific mutations in a pilus-associated protein (Bd0108) mutant background were necessary for biofilm formation, including secretion of extracellular DNA (eDNA), proteins, and polysaccharides matrix components. Remarkably, fliL disruption strongly reduced biofilm development. All H-I variants grew similarly without prey, showed a strain-specific reduction in predatory ability in prey suspensions, but maintained similar high efficiency in prey biofilms. Population-wide allele sequencing suggested additional routes to host independence. Thus, stator and invasion pole-dependent signaling control the H-D and the H-I biofilm-forming phenotypes, with single mutations overriding prey requirements, and enabling shifts from obligate to facultative predation, with potential consequences on community dynamics. Our findings on the facility and variety of changes leading to facultative predation also challenge the concept of Bdellovibrio and like organisms being obligate predators.<br><br>IMPORTANCE: The ability of bacteria to form biofilms is a central research theme in biology, medicine, and the environment. We show that cultures of the obligate (host-dependent) "solitary" predatory bacterium Bdellovibrio bacteriovorus, which cannot replicate without prey, can use various genetic routes to spontaneously yield host-independent (H-I) variants that grow axenically (as a single species, in the absence of prey) and exhibit various surface attachment phenotypes, including biofilm formation. These routes include single mutations in flagellar stator genes that affect biofilm formation, provoke motor instability and large motility defects, and disrupt cyclic-di-GMP intracellular signaling. H-I strains also exhibit reduced predatory efficiency in suspension but high efficiency in prey biofilms. These changes override the requirements for prey, enabling a shift from obligate to facultative predation, with potential consequences on community dynamics.}, }
@article {pmid39035353, year = {2024}, author = {Zuberi, A and Ahmad, N and Ahmad, H and Saeed, M and Ahmad, I}, title = {Beyond antibiotics: CRISPR/Cas9 triumph over biofilm-associated antibiotic resistance infections.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1408569}, pmid = {39035353}, issn = {2235-2988}, mesh = {*Biofilms/drug effects/growth &amp; development ; *CRISPR-Cas Systems ; *Anti-Bacterial Agents/pharmacology ; Humans ; Bacteria/drug effects/genetics ; Drug Resistance, Bacterial/genetics ; Bacterial Infections/microbiology/drug therapy ; Gene Editing ; }, abstract = {A complex structure known as a biofilm is formed when a variety of bacterial colonies or a single type of cell in a group sticks to a surface. The extracellular polymeric compounds that encase these cells, often consisting of proteins, eDNA, and polysaccharides, exhibit strong antibiotic resistance. Concerns about biofilm in the pharmaceutical industry, public health, and medical fields have sparked a lot of interest, as antibiotic resistance is a unique capacity exhibited by these biofilm-producing bacteria, which increases morbidity and death. Biofilm formation is a complicated process that is controlled by several variables. Insights into the processes to target for the therapy have been gained from multiple attempts to dissect the biofilm formation process. Targeting pathogens within a biofilm is profitable because the bacterial pathogens become considerably more resistant to drugs in the biofilm state. Although biofilm-mediated infections can be lessened using the currently available medications, there has been a lot of focus on the development of new approaches, such as bioinformatics tools, for both treating and preventing the production of biofilms. Technologies such as transcriptomics, metabolomics, nanotherapeutics and proteomics are also used to develop novel anti-biofilm agents. These techniques help to identify small compounds that can be used to inhibit important biofilm regulators. The field of appropriate control strategies to avoid biofilm formation is expanding quickly because of this spurred study. As a result, the current article addresses our current knowledge of how biofilms form, the mechanisms by which bacteria in biofilms resist antibiotics, and cutting-edge treatment approaches for infections caused by biofilms. Furthermore, we have showcased current ongoing research utilizing the CRISPR/Cas9 gene editing system to combat bacterial biofilm infections, particularly those brought on by lethal drug-resistant pathogens, concluded the article with a novel hypothesis and aspirations, and acknowledged certain limitations.}, }
@article {pmid39035281, year = {2024}, author = {Wongsuwanlert, M and Teanpaisan, R and Ruangsri, P and Kaewdech, A and Sunpaweravong, S and Pahumunto, N}, title = {Effect of mouthwash containing poly l-Lysine and glycerol monolaurate on oral Helicobacter pylori relating to biofilm eradication, anti-adhesion, and pro-inflammatory cytokine suppression.}, journal = {Journal of dental sciences}, volume = {19}, number = {3}, pages = {1748-1757}, pmid = {39035281}, issn = {2213-8862}, abstract = {BACKGROUND/PURPOSE: Helicobacter pylori has been found to be related to periodontitis, and the oral cavity has been considered a reservoir for H. pylori gastritis infection. Thus, this study evaluated the effect of mouthwash containing poly l-Lysine and glycerol monolaurate on inhibiting H. pylori growth, biofilm formation, cell cytotoxicity, adhesion ability, cagA mRNA expression, and pro-inflammatory cytokines stimulated by H. pylori.<br><br>MATERIALS AND METHODS: Nineteen H. pylori strains were isolated from the oral cavity. The effectiveness of mouthwash containing poly l-Lysine and glycerol monolaurate was examined for its ability to inhibit H. pylori growth and biofilm formation and was tested for cell viability in oral epithelial cells (H357), gastric adenocarcinoma cells (AGS), and periodontal ligament cells (PDL). Additionally, the mouthwash was tested for reducing cagA mRNA expression, adhesion ability to H357 and AGS cells, and pro-inflammatory cytokines stimulated with H. pylori in AGS and PDL cells.<br><br>RESULTS: The mouthwash containing poly l-Lysine and glycerol monolaurate could eradicate the biofilm by 14.9-19.9% after incubation at 5&#xa0;min, and cell viability revealed 77.2, 79.8, and 100.0% for AGS, H357, and PDL cells, respectively. Moreover, the mouthwash containing poly l-Lysine and glycerol monolaurate could down-regulate cagA mRNA expression, reduce adhesion of H. pylori by approximately 9.5-47.8% for H357&#xa0;cells and 24.5-62.9% for AGS cells, and decrease pro-inflammatory cytokines, especially interleukin-8, stimulated with H. pylori.<br><br>CONCLUSION: Mouthwash containing poly l-Lysine and glycerol monolaurate could inhibit H. pylori growth and reduce their virulence expression. The mouthwash also revealed low cytotoxicity to oral and gastric cells.}, }
@article {pmid39034023, year = {2024}, author = {Liu, Y and Dai, A and Xia, L and Zhou, Y and Ren, T and Huang, Y and Zhou, Y}, title = {Deciphering the roles of nitrogen source in sharping synchronous metabolic pathways of linear alkylbenzene sulfonate and nitrogen in a membrane biofilm for treating greywater.}, journal = {Environmental research}, volume = {260}, number = {}, pages = {119650}, doi = {10.1016/j.envres.2024.119650}, pmid = {39034023}, issn = {1096-0953}, mesh = {*Biofilms/drug effects ; *Nitrogen/metabolism ; *Waste Disposal, Fluid/methods ; *Alkanesulfonic Acids/metabolism ; Water Pollutants, Chemical/metabolism ; Wastewater/chemistry/microbiology ; Metabolic Networks and Pathways ; Ammonia/metabolism ; Urea/metabolism ; Water Purification/methods ; Bioreactors/microbiology ; }, abstract = {Nitrogen (N) source is an important factor affecting biological wastewater treatment. Although the oxygen-based membrane biofilm showed excellent greywater treatment performance, how N source impacts the synchronous removal of organics and N is still unclear. In this work, how N species (urea, nitrate and ammonia) affect synchronous metabolic pathways of organics and N were evaluated during greywater treatment in the membrane biofilm. Urea and ammonia achieved efficient chemical oxygen demand (>97.5%) and linear alkylbenzene sulfonate (LAS, >98.5%) removal, but nitrate enabled the maximum total N removal (80.8 ± 2.6%). The nitrate-added system had poor LAS removal ratio and high residual LAS, promoting the accumulation of effluent protein-like organics and fulvic acid matter. N source significantly induced bacterial community succession, and the increasing of corresponded functional flora can promote the transformation and utilization of microbial-mediated N. The nitrate system was more conducive to the accumulation of denitrification related microorganisms and enzymes, enabling the efficient N removal. Combining with high amount of ammonia monooxygenase that contributing to LAS and N co-metabolism, LAS mineralization related microbes and functional enzymes were generously accumulated in the urea and ammonia systems, which achieved the high efficiency of organics and LAS removal.}, }
@article {pmid39033146, year = {2024}, author = {Varin-Simon, J and Colin, M and Velard, F and Tang-Fichaux, M and Ohl, X and Mongaret, C and Gangloff, SC and Reffuveille, F}, title = {Cutibacterium acnes biofilm formation is influenced by bone microenvironment, implant surfaces and bacterial internalization.}, journal = {BMC microbiology}, volume = {24}, number = {1}, pages = {270}, pmid = {39033146}, issn = {1471-2180}, mesh = {*Biofilms/growth &amp; development ; *Titanium ; *Prosthesis-Related Infections/microbiology ; Humans ; Bacterial Adhesion ; Propionibacteriaceae/physiology/genetics/drug effects ; Prostheses and Implants/microbiology ; Bone and Bones/microbiology ; Plastics ; Alloys ; Surface Properties ; }, abstract = {BACKGROUND: The bacterial persistence, responsible for therapeutic failures, can arise from the biofilm formation, which possesses a high tolerance to antibiotics. This threat often occurs when a bone and joint infection is diagnosed after a prosthesis implantation. Understanding the biofilm mechanism is pivotal to enhance prosthesis joint infection (PJI) treatment and prevention. However, little is known on the characteristics of Cutibacterium acnes biofilm formation, whereas this species is frequently involved in prosthesis infections.<br><br>METHODS: In this study, we compared the biofilm formation of C. acnes PJI-related strains and non-PJI-related strains on plastic support and textured titanium alloy by (i) counting adherent and viable bacteria, (ii) confocal scanning electronic microscopy observations after biofilm matrix labeling and (iii) RT-qPCR experiments.<br><br>RESULTS: We highlighted material- and strain-dependent modifications of C. acnes biofilm. Non-PJI-related strains formed aggregates on both types of support but with different matrix compositions. While the proportion of polysaccharides signal was higher on plastic, the proportions of polysaccharides and proteins signals were more similar on titanium. The changes in biofilm composition for PJI-related strains was less noticeable. For all tested strains, biofilm formation-related genes were more expressed in biofilm formed on plastic that one formed on titanium. Moreover, the impact of C. acnes internalization in osteoblasts prior to biofilm development was also investigated. After internalization, one of the non-PJI-related strains biofilm characteristics were affected: (i) a lower quantity of adhered bacteria (80.3-fold decrease), (ii) an increase of polysaccharides signal in biofilm and (iii) an activation of biofilm gene expressions on textured titanium disk.<br><br>CONCLUSION: Taken together, these results evidenced the versatility of C. acnes biofilm, depending on the support used, the bone environment and the strain.}, }
@article {pmid39033094, year = {2024}, author = {Xu, KZ and You, C and Wang, YJ and Dar, OI and Yin, LJ and Xiang, SL and Jia, AQ}, title = {Repurposing promethazine hydrochloride to inhibit biofilm formation against Burkholderia thailandensis.}, journal = {Medical microbiology and immunology}, volume = {213}, number = {1}, pages = {16}, pmid = {39033094}, issn = {1432-1831}, support = {Qhyb2022-46//Innovative Research Projects for Postgraduates in Hainan Province/ ; Qhyb2021-38//Innovative Research Projects for Postgraduates in Hainan Province/ ; 82160664//National Natural Science Foundation of China/ ; 221CXTD434//Natural Science Foundation of Hainan Province/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Burkholderia/drug effects/physiology/genetics ; *Promethazine/pharmacology ; *Drug Repositioning ; Molecular Docking Simulation ; Anti-Bacterial Agents/pharmacology ; Lipase/metabolism/genetics ; Gene Expression Regulation, Bacterial/drug effects ; Bacterial Proteins/genetics/metabolism ; Humans ; Quorum Sensing/drug effects ; }, abstract = {Melioidosis is a severe infectious disease caused by Burkholderia pseudomallei, an intracellular pathogen with a high mortality rate and significant antibiotic resistance. The high mortality rate and resistance to antibiotics have drawn considerable attention from researchers studying melioidosis. This study evaluated the effects of various concentrations (75, 50, and 25 µg/mL) of promethazine hydrochloride (PTZ), a potent antihistamine, on biofilm formation and lipase activity after 24 h of exposure to B. thailandensis E264. A concentration-dependent decrease in both biofilm biomass and lipase activity was observed. RT-PCR analysis revealed that PTZ treatment not only made the biofilm structure loose but also reduced the expression of btaR1, btaR2, btaR3, and scmR. Single gene knockouts of quorum sensing (QS) receptor proteins (∆btaR1, ∆btaR2, and ∆btaR3) were successfully constructed. Deletion of btaR1 affected biofilm formation in B. thailandensis, while deletion of btaR2 and btaR3 led to reduced lipase activity. Molecular docking and biological performance results demonstrated that PTZ inhibits biofilm formation and lipase activity by suppressing the expression of QS-regulated genes. This study found that repositioning PTZ reduced biofilm formation in B. thailandensis E264, suggesting a potential new approach for combating melioidosis.}, }
@article {pmid39033083, year = {2024}, author = {Almeida Junior, HL and Assis, TM and Faria, EC and Costa, LRK and Ibaldo, BM}, title = {Piedraia hortae: biofilm formation and its importance in the pathogenesis of Piedra nigra (black piedra).}, journal = {Anais brasileiros de dermatologia}, volume = {99}, number = {6}, pages = {863-868}, pmid = {39033083}, issn = {1806-4841}, mesh = {*Biofilms/growth &amp; development ; *Microscopy, Electron, Scanning ; Piedra/microbiology/pathology ; Humans ; Hyphae ; }, abstract = {BACKGROUND: Little is known about the ultrastructure of Piedraia hortae.<br><br>OBJECTIVE: To examine a P. hortae colony with scanning electron microscopy and investigate possible contributions to its the pathogenesis of black piedra.<br><br>RESULTS: On low magnifications, two distinct aspects of the colony are identified, a compact area and a filamentous area. Analysis of the filamentous area demonstrates hyphae adhered by a thin reticular substance. A recurring finding is the adhesion between the fungal filaments in parallel. On high magnifications, the microfibrillar substance adhering the hyphae to each other becomes very evident. Examination of the compact area shows the hyphae embedded in the reticular matrix forming a biofilm and the colony well adhered. On high magnification, it can be observed that the hyphae are within this fibrillar matrix, which has the same appearance as the filamentous substance that adheres the hyphae to each other.<br><br>STUDY LIMITATIONS: Only one strain was examined.<br><br>CONCLUSIONS: The formation of biofilm with fungal structures and reticulated extracellular substance is important in the pathogenesis of black piedra.}, }
@article {pmid39031267, year = {2024}, author = {Allami, M and Mohammed, EJ and Alnaji, Z and A Jassim, S}, title = {Antibiotic resistance and its correlation with biofilm formation and virulence genes in Klebsiella pneumoniae isolated from wounds.}, journal = {Journal of applied genetics}, volume = {65}, number = {4}, pages = {925-935}, pmid = {39031267}, issn = {2190-3883}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Klebsiella pneumoniae/genetics/pathogenicity/drug effects/isolation &amp; purification ; *Anti-Bacterial Agents/pharmacology ; Virulence/genetics ; *beta-Lactamases/genetics ; Humans ; *Klebsiella Infections/microbiology ; Microbial Sensitivity Tests ; Virulence Factors/genetics ; Drug Resistance, Multiple, Bacterial/genetics ; Imipenem/pharmacology ; Bacterial Proteins/genetics ; }, abstract = {Klebsiella pneumoniae is the most important species of the Klebsiella genus and often causes hospital infections. These bacteria have a high resistance to most of the available drugs, which has caused concern all over the world. In this study, we investigated the antibiotic resistance profile and the ability to produce extended-spectrum beta-lactamase (ESBL) among K. pneumoniae isolates, and then we investigated the relationship between these two factors with biofilm formation and the prevalence of different virulence genes. In this study, 130 isolates of K. pneumoniae isolated from wounds were investigated. The antibiotic resistance of the isolates was evaluated by the disk diffusion method. The microtiter plate method was used to measure biofilm formation. The prevalence of virulence genes was detected by multiplex PCR. Among the examined isolates, 85.3% showed multidrug resistance. 87.6% of the isolates were ESBL-positive. Imipenem, meropenem, and fosfomycin were the most effective drugs. The ability of the isolates to produce biofilm was strong (80%), moderate (12.3%), and weak (7.6%), respectively. fimH, mrKD, entB, and tolC virulence genes were observed in all isolates. High prevalence of antibiotic resistance (especially multidrug resistance), high prevalence of ESBL-producing isolates, the ability of all isolates to biofilm formation, and the presence of fimH, mrKD, entB, and tolC virulence genes in all isolates show the importance of these factors in the pathogenesis of K. pneumoniae isolates in Iraq.}, }
@article {pmid39030869, year = {2024}, author = {Hou, Z and Ren, X and Sun, Z and An, R and Huang, M and Gao, C and Yin, M and Liu, G and He, D and Du, H and Tang, R}, title = {Trash into Treasure: Nano-coating of Catheter Utilizes Urine to Deprive H2S Against Persister and Rip Biofilm Matrix.}, journal = {Advanced healthcare materials}, volume = {13}, number = {27}, pages = {e2401067}, doi = {10.1002/adhm.202401067}, pmid = {39030869}, issn = {2192-2659}, support = {82101011,82260477//National Natural Science Foundation of China/ ; lzujbky-2022-ey19//Fundamental Research Funds for the Central Universities/ ; 20YF8WA084,20YF8FA073//Natural Science Foundation of Gansu Province of China/ ; 20JR10FA670//Scientific and Technological Foundation of Gansu Province/ ; GXH20220530-16//Gansu Association for Science and Technology/ ; 20JR10RA653-ZDKF20210301//open fund of Key Laboratory of Dental Maxillofacial Reconstruction and Biological Intelligence Manufacturing, Gansu Province/ ; lzuyxcx-2022-182//Medical Innovation and Development Project of Lanzhou University/ ; lzukqky-2021-q01,lzukqky-2021-q07,lzukqky-2022-q03//Hospital of Stomatology Lanzhou University Scientific Research Project/ ; 2024B-003//Education Technology Innovation Project of Gansu Province in 2024/ ; PKUSS20200103//Youth Research Fund of Peking University School and Hospital of Stomatology/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Hydrogen Sulfide/chemistry ; *Urease/metabolism ; *Metal Nanoparticles/chemistry ; Anti-Bacterial Agents/chemistry/pharmacology ; Silver/chemistry ; Humans ; Urine/microbiology/chemistry ; Catheters/microbiology ; Urinary Tract Infections/prevention &amp; control/microbiology/drug therapy ; Escherichia coli/drug effects ; Catheter-Related Infections/prevention &amp; control/microbiology ; Microbial Sensitivity Tests ; }, abstract = {Bacteria-derived hydrogen sulfide (H2S) often contributes to the emergence of antibiotic-recalcitrant bacteria, especially persister (a sub-population of dormant bacteria), thus causing the treatment failure of Catheter-associated urinary tract infection (CAUTI). Here, an H2S harvester nanosystem to prevent the generation of persister bacteria and disrupt the dense biofilm matrix by the self-adaptive ability of shape-morphing is prepared. The nanosystem possesses a core-shell structure that is composed of liquid metal nanoparticle (LM NP), AgNPs, and immobilized urease. The nanosystem decomposes urea contained in urine to generate ammonia for eliminating bacteria-derived H2S. Depending on the oxidative layer of liquid metal, the nanosystem also constitutes a long-lasting reservoir for temporarily storing bacteria-derived H2S, when urease transiently overloads or in the absence of urine in a catheter. Depriving H2S can prevent the emergence of persistent bacteria, enhancing the bacteria-killing efficiency of Ga[3+] and Ag[+] ions. Even when the biofilm has formed, the urine flow provides heat to trigger shape morphing of the LM NP, tearing the biofilm matrix. Collectively, this strategy can turn trash (urea) into treasure (H2S scavengers and biofilm rippers), and provides a new direction for the antibacterial materials application in the medical field.}, }
@article {pmid39029506, year = {2024}, author = {Montoya-Hinojosa, EI and Villarreal-Treviño, L and Bocanegra-Ibarias, P and Camacho-Ortiz, A and Flores-Treviño, S}, title = {Drug Resistance in Biofilm and Planktonic Cells of Achromobacter spp., Burkholderia spp., and Stenotrophomonas maltophilia Clinical Isolates.}, journal = {Microbial drug resistance (Larchmont, N.Y.)}, volume = {30}, number = {9}, pages = {354-362}, doi = {10.1089/mdr.2023.0301}, pmid = {39029506}, issn = {1931-8448}, mesh = {*Biofilms/drug effects ; *Stenotrophomonas maltophilia/drug effects ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology ; Humans ; *Burkholderia/drug effects ; *Achromobacter/drug effects ; *Gram-Negative Bacterial Infections/microbiology/drug therapy ; Drug Resistance, Bacterial ; Trimethoprim, Sulfamethoxazole Drug Combination/pharmacology ; Mexico ; Ceftazidime/pharmacology ; Plankton/drug effects ; Drug Resistance, Multiple, Bacterial ; Levofloxacin/pharmacology ; }, abstract = {Background: Biofilm production in nonfermenting Gram-negative bacteria influences drug resistance. The aim of this work was to evaluate the effect of different antibiotics on biofilm eradication of clinical isolates of Achromobacter, Burkholderia, and Stenotrophomonas maltophilia. Methods: Clinical isolates were identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry in a third-level hospital in Monterrey, Mexico. Crystal violet staining was used to determine biofilm production. Drug susceptibility testing was determined by broth microdilution in planktonic cells and biofilm cells. Results: Resistance in planktonic cells was moderate to trimethoprim-sulfamethoxazole, and low to chloramphenicol, minocycline, levofloxacin (S. maltophilia and Burkholderia), ceftazidime, and meropenem (Burkholderia and Achromobacter). Biofilm eradication required higher drug concentrations of ceftazidime, chloramphenicol, levofloxacin, and trimethoprim-sulfamethoxazole than planktonic cells (p < 0.05). Levofloxacin showed biofilm eradication activity in S. maltophilia, minocycline and meropenem in Burkholderia, and meropenem in Achromobacter. Conclusions: Drug resistance increased due to biofilm production for some antibiotics, particularly ceftazidime and trimethoprim-sulfamethoxazole for all three pathogens, chloramphenicol for S. maltophilia and Burkholderia, and levofloxacin for Burkholderia. Some antibiotics could be used for the treatment of biofilm-associated infections in our population, such as levofloxacin for S. maltophilia, minocycline and meropenem for Burkholderia, and meropenem for Achromobacter.}, }
@article {pmid39028551, year = {2024}, author = {Malik, A and Oludiran, A and Poudel, A and Alvarez, OB and Woodward, C and Purcell, EB}, title = {RelQ-mediated alarmone signalling regulates growth, stress-induced biofilm formation and spore accumulation in Clostridioides difficile.}, journal = {Microbiology (Reading, England)}, volume = {170}, number = {7}, pages = {}, pmid = {39028551}, issn = {1465-2080}, support = {R15 AI156650/AI/NIAID NIH HHS/United States ; LEAPS- MPS 2213353//National Science Foundation/ ; }, mesh = {*Biofilms/growth &amp; development ; *Clostridioides difficile/genetics/metabolism/physiology/growth &amp; development ; *Spores, Bacterial/growth &amp; development/metabolism/genetics ; *Bacterial Proteins/genetics/metabolism ; *Gene Expression Regulation, Bacterial ; *Signal Transduction ; *Stress, Physiological ; Anti-Bacterial Agents/pharmacology ; Ligases/genetics/metabolism ; Gene Deletion ; Oxidative Stress ; }, abstract = {The bacterial stringent response (SR) is a conserved transcriptional reprogramming pathway mediated by the nucleotide signalling alarmones, (pp)pGpp. The SR has been implicated in antibiotic survival in Clostridioides difficile, a biofilm- and spore-forming pathogen that causes resilient, highly recurrent C. difficile infections. The role of the SR in other processes and the effectors by which it regulates C. difficile physiology are unknown. C. difficile RelQ is a clostridial alarmone synthetase. Deletion of relQ dysregulates C. difficile growth in unstressed conditions, affects susceptibility to antibiotic and oxidative stressors and drastically reduces biofilm formation. While wild-type C. difficile displays increased biofilm formation in the presence of sublethal stress, the ΔrelQ strain cannot upregulate biofilm production in response to stress. Deletion of relQ slows spore accumulation in planktonic cultures but accelerates it in biofilms. This work establishes biofilm formation and spore accumulation as alarmone-mediated processes in C. difficile and reveals the importance of RelQ in stress-induced biofilm regulation.}, }
@article {pmid39027105, year = {2024}, author = {Wang, L and Liu, P and Wu, Y and Pei, H and Cao, X}, title = {Inhibitory effect of Lonicera japonica flos on Streptococcus mutans biofilm and mechanism exploration through metabolomic and transcriptomic analyses.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1435503}, pmid = {39027105}, issn = {1664-302X}, abstract = {INTRODUCTION: Streptococcus mutans was the primary pathogenic organism responsible for dental caries. Lonicera japonica flos (LJF) is a traditional herb in Asia and Europe and consumed as a tea beverage for thousands of years.<br><br>METHODS: The inhibitory effect and mechanism of LJF on biofilm formation by S. mutans was investigated. The active extracts of LJF were validated for their inhibitory activity by examining changes in surface properties such as adherence, hydrophobicity, auto-aggregation abilities, and exopolysaccharides (EPS) production, including water-soluble glucan and water-insoluble glucan.<br><br>RESULTS AND DISCUSSION: LJF primarily inhibited biofilm formation through the reduction of EPS production, resulting in alterations in cell surface characteristics and growth retardation in biofilm formation cycles. Integrated transcriptomic and untargeted metabolomics analyses revealed that EPS production was modulated through two-component systems (TCS), quorum sensing (QS), and phosphotransferase system (PTS) pathways under LJF stress conditions. The sensing histidine kinase VicK was identified as an important target protein, as LJF caused its dysregulated expression and blocked the sensing of autoinducer II (AI-2). This led to the inhibition of response regulator transcriptional factors, down-regulated glycosyltransferase (Gtf) activity, and decreased production of water-insoluble glucans (WIG) and water-soluble glucans (WSG). This is the first exploration of the inhibitory effect and mechanism of LJF on S. mutans, providing a theoretical basis for the application of LJF in functional food, oral health care, and related areas.}, }
@article {pmid39026137, year = {2024}, author = {Jagaba, AH and Abdulazeez, I and Lawal, DU and Affam, AC and Mu'azu, ND and Soja, UB and Usman, AK and Noor, A and Lim, JW and Aljundi, IH}, title = {A review on the application of biochar as an innovative and sustainable biocarrier material in moving bed biofilm reactors for dye removal from environmental matrices.}, journal = {Environmental geochemistry and health}, volume = {46}, number = {9}, pages = {333}, pmid = {39026137}, issn = {1573-2983}, mesh = {*Charcoal/chemistry ; *Biofilms ; *Coloring Agents/chemistry ; *Bioreactors ; Water Pollutants, Chemical ; Biodegradation, Environmental ; Waste Disposal, Fluid/methods ; }, abstract = {Dye decolorization through biological treatment techniques has been gaining momentum as it is based on suspended and attached growth biomass in both batch and continuous modes. Hence, this review focused on the contribution of moving bed biofilm reactors (MBBR) in dye removal. MBBR have been demonstrated to be an excellent technology for pollution extraction, load shock resistance, and equipment size and energy consumption reduction. The review went further to highlight different biocarrier materials for biofilm development this review identified biochar as an innovative and environmentally friendly material produced through the application of different kinds of reusable or recyclable wastes and biowastes. Biochar as a carbonized waste biomass could be a better competitor and environmentally friendly substitute to activated carbon given its lower mass costs. Biochar can be easily produced particularly in rural locations where there is an abundance of biomass-based trash. Given that circular bioeconomy lowers dependency on natural resources by turning organic wastes into an array of useful products, biochar empowers the creation of competitive goods. Thus, biochar was identified as a novel, cost-effective, and long-term management strategy since it brings about several essential benefits, including food security, climate change mitigation, biodiversity preservation, and sustainability improvement. This review concludes that integrating two treatment methods could greatly lead to better color, organic matter, and nutrients removal than a single biological MBBR treatment process.}, }
@article {pmid39024943, year = {2024}, author = {Wang, X and Chen, C and Hu, J and Liu, C and Ning, Y and Lu, F}, title = {Current strategies for monitoring and controlling bacterial biofilm formation on medical surfaces.}, journal = {Ecotoxicology and environmental safety}, volume = {282}, number = {}, pages = {116709}, doi = {10.1016/j.ecoenv.2024.116709}, pmid = {39024943}, issn = {1090-2414}, mesh = {*Biofilms/drug effects/growth &amp; development ; Biosensing Techniques/methods ; Equipment and Supplies/microbiology ; Bacteria/drug effects/growth &amp; development ; Anti-Bacterial Agents/pharmacology ; Drug Resistance, Multiple, Bacterial ; }, abstract = {Biofilms, intricate microbial communities that attach to surfaces, especially medical devices, form an exopolysaccharide matrix, which enables bacteria to resist environmental pressures and conventional antimicrobial agents, leading to the emergence of multi-drug resistance. Biofilm-related infections associated with medical devices are a significant public health threat, compromising device performance. Therefore, developing effective methods for supervising and managing biofilm growth is imperative. This in-depth review presents a systematic overview of strategies for monitoring and controlling bacterial biofilms. We first outline the biofilm creation process and its regulatory mechanisms. The discussion then progresses to advancements in biosensors for biofilm detection and diverse treatment strategies. Lastly, this review examines the obstacles and new perspectives associated with this domain to facilitate the advancement of innovative monitoring and control solutions. These advancements are vital in combating the spread of multi drug-resistant bacteria and mitigating public health risks associated with infections from biofilm formation on medical instruments.}, }
@article {pmid39023225, year = {2024}, author = {Zhao, L and Li, W and Liu, Y and Qi, Y and An, N and Yan, M and Wang, Z and Zhou, M and Yang, S}, title = {Designing Fast-Moving Antibacterial Microtorpedoes to Treat Lethal Bacterial Biofilm Infections.}, journal = {ACS nano}, volume = {}, number = {}, pages = {}, doi = {10.1021/acsnano.4c04995}, pmid = {39023225}, issn = {1936-086X}, abstract = {Engineering fast-moving microrobot swarms that can physically disassemble bacterial biofilms and kill the bacteria released from the biofilms is a promising way to combat bacterial biofilm infections. Here, we report electrochemical design of Ag7O8NO3 microtorpedoes with outstanding antibacterial performance and meanwhile capable of moving at speeds of hundreds of body lengths per second in clinically used H2O2 aqueous solutions. These fast-moving antibacterial Ag7O8NO3 microtorpedoes could penetrate into and disintegrate the bacterial biofilms and, in turn, kill the bacteria released from the biofilms. Based on the understanding of the growth behavior of the microtorpedoes, we could fine-tune the morphology of the microtorpedoes to accelerate the moving speed and increase their penetration depth into the biofilms simply via controlling the potential waveforms. We further developed an automatic shaking method to selectively peel off the uniformly structured microtorpedoes from the electrode surface, realizing continuous electrochemical production of the microtorpedoes. Animal experiments proved that the microtorpedo swarms greatly increased the survival rate of the mice infected by lethal biofilms to >90%. We used the electrochemical method to design and massively produce uniformly structured fast-moving antibacterial microtorpedo swarms with application potentials in treatment of lethal bacterial biofilm infections.}, }
@article {pmid39023091, year = {2024}, author = {Li, C and Gao, D and Li, C and Cheng, G and Zhang, L}, title = {Fighting against biofilm: The antifouling and antimicrobial material.}, journal = {Biointerphases}, volume = {19}, number = {4}, pages = {}, doi = {10.1116/6.0003695}, pmid = {39023091}, issn = {1559-4106}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Biofouling/prevention &amp; control ; *Anti-Infective Agents/pharmacology/chemistry ; Biocompatible Materials/chemistry/pharmacology ; Anti-Bacterial Agents/pharmacology/chemistry ; }, abstract = {Biofilms are groups of microorganisms protected by self-secreted extracellular substances. Biofilm formation on the surface of biomaterial or engineering materials becomes a severe challenge. It has caused significant health, environmental, and societal concerns. It is believed that biofilms lead to life-threatening infection, medical implant failure, foodborne disease, and marine biofouling. To address these issues, tremendous effort has been made to inhibit biofilm formation on materials. Biofilms are extremely difficult to treat once formed, so designing material and coating bearing functional groups that are capable of resisting biofilm formation has attracted increasing attention for the last two decades. Many types of antibiofilm strategies have been designed to target different stages of biofilm formation. Development of the antibiofilm material can be classified into antifouling material, antimicrobial material, fouling release material, and integrated antifouling/antimicrobial material. This review summarizes relevant research utilizing these four approaches and comments on their antibiofilm properties. The feature of each method was compared to reveal the research trend. Antibiofilm strategies in fundamental research and industrial applications were summarized.}, }
@article {pmid39021701, year = {2024}, author = {Andersen, JB and Rybtke, M and Tolker-Nielsen, T}, title = {The dynamics of biofilm development and dispersal should be taken into account when quantifying biofilm via the crystal violet microtiter plate assay.}, journal = {Biofilm}, volume = {8}, number = {}, pages = {100207}, pmid = {39021701}, issn = {2590-2075}, abstract = {The crystal violet microtiter plate biofilm assay is often used to compare the amount of biofilm formed by a mutant versus wild-type or a compound-treated biofilm versus the non-treatment control. In many of these studies the amount of biofilm is assessed only at one single time point. However, if the dynamics of biofilm development of the mutant (or compound-treated biofilm) is different than that of the wild-type (or non-treatment control), then biofilm quantification at a single time point may give misleading results. To overcome this shortcoming of the common biofilm quantification technique, we recommend to use a serial dilution-based crystal violet microtiter plate biofilm assay for easy assessment of the dynamics of biofilm development and dispersal. We demonstrate that the dilution-resolved crystal violet assay displays the dynamics of Pseudomonas aeruginosa biofilm development and dispersal as efficient as a time-resolved crystal violet assay. In addition, focusing on mutants of different parts of the c-di-GMP signaling system in P. aeruginosa, we provide an example illustrating the need to assess biofilm dynamics instead of quantifying biofilm biomass at a single time point.}, }
@article {pmid39021314, year = {2024}, author = {Gomes Guimarães, G and Alves, F and Gonçalves, I and Silva E Carvalho, I and Toneth Ponce Ayala, E and Pratavieira, S and Salvador Bagnato, V}, title = {The synergistic effect of photodynamic and sonodynamic inactivation against Candida albicans biofilm.}, journal = {Journal of biophotonics}, volume = {17}, number = {9}, pages = {e202400190}, doi = {10.1002/jbio.202400190}, pmid = {39021314}, issn = {1864-0648}, support = {001//Coordena&#xe7;&#xe3;o de Aperfei&#xe7;oamento Pessoal de N&#xed;vel Superior (CAPES)/ ; 465&#x2009;360/2014-9//National Council for Scientific and Technological Development-CNPq/ ; 306919/2019-2//National Council for Scientific and Technological Development-CNPq/ ; 305072/2022-6//National Council for Scientific and Technological Development-CNPq/ ; 131017/2022-5//National Council for Scientific and Technological Development-CNPq/ ; 440237/2021-1//National Council for Scientific and Technological Development-CNPq/ ; 2013/07276-1//S&#xe3;o Paulo Research Foundation (FAPESP)/ ; 2014/50857-8//S&#xe3;o Paulo Research Foundation (FAPESP)/ ; 2021/01324-0//S&#xe3;o Paulo Research Foundation (FAPESP)/ ; }, mesh = {*Biofilms/drug effects ; *Candida albicans/drug effects/physiology ; *Curcumin/pharmacology ; Microbial Viability/drug effects ; Light ; Ultrasonic Waves ; Photosensitizing Agents/pharmacology ; Photochemotherapy ; }, abstract = {Candida albicans biofilm can cause diseases that are resistant to conventional antifungal agents. Photodynamic (PDI), sonodynamic (SDI), and sonophotodynamic (SPDI) inactivation have arisen as promising antimicrobial strategies. This study evaluated these treatments mediated by curcumin against C. albicans biofilms. For this, C. albicans biofilms were submitted to PDI, SDI, or SPDI with different light and ultrasound doses, then, the viability assay was performed to measure the effectiveness. Finally, a mathematical model was suggested to fit acquired experimental data and understand the synergistic effect of light and ultrasound in different conditions. The results showed that SPDI, PDI, and SDI reduced the viability in 6 ± 1; 1 ± 1; and 2 ± 1 log, respectively, using light at 60 J/cm[2], ultrasound at 3 W/cm[2], and 80 μM of curcumin. The viability reduction was proportional to the ultrasound and light doses delivered. These results encourage the use of SPDI for the control of microbial biofilm.}, }
@article {pmid39021233, year = {2024}, author = {Emiliano, JVDS and Fusieger, A and Camargo, AC and Rodrigues, FFDC and Nero, LA and Perrone, &#xcd;T and Carvalho, AF}, title = {Staphylococcus aureus in Dairy Industry: Enterotoxin Production, Biofilm Formation, and Use of Lactic Acid Bacteria for Its Biocontrol.}, journal = {Foodborne pathogens and disease}, volume = {21}, number = {10}, pages = {601-616}, doi = {10.1089/fpd.2023.0170}, pmid = {39021233}, issn = {1556-7125}, mesh = {*Biofilms ; *Staphylococcus aureus/physiology ; *Enterotoxins/metabolism ; *Food Microbiology ; Humans ; Animals ; Lactobacillales/physiology/metabolism ; Dairying ; Bacteriocins/metabolism ; Food Contamination/prevention &amp; control ; Milk/microbiology ; }, abstract = {Staphylococcus aureus is a well-known pathogen capable of producing enterotoxins during bacterial growth in contaminated food, and the ingestion of such preformed toxins is one of the major causes of food poisoning around the world. Nowadays 33 staphylococcal enterotoxins (SEs) and SE-like toxins have been described, but nearly 95% of confirmed foodborne outbreaks are attributed to classical enterotoxins SEA, SEB, SEC, SED, and SEE. The natural habitat of S. aureus includes the skin and mucous membranes of both humans and animals, allowing the contamination of milk, its derivatives, and the processing facilities. S. aureus is well known for the ability to form biofilms in food processing environments, which contributes to its persistence and cross-contamination in food. The biocontrol of S. aureus in foods by lactic acid bacteria (LAB) and their bacteriocins has been studied for many years. Recently, LAB and their metabolites have also been explored for controlling S. aureus biofilms. LAB are used in fermented foods since in ancient times and nowadays characterized strains (or their purified bacteriocin) can be intentionally added to prolong food shelf-life and to control the growth of potentially pathogenic bacteria. Regarding the use of these microorganism and their metabolites (such as organic acids and bacteriocins) to prevent biofilm development or for biofilm removal, it is possible to conclude that a complex network behind the antagonistic activity remains poorly understood at the molecular level. The use of approaches that allow the characterization of these interactions is necessary to enhance our understanding of the mechanisms that govern the inhibitory activity of LAB against S. aureus biofilms in food processing environments.}, }
@article {pmid39020257, year = {2024}, author = {Zarei, M and Ghahfarokhi, MG and Sabaeian, M and Sepahi, M and Alirezaie, S and Mohebi, M}, title = {Effect of plasma-activated water on planktonic and biofilm cells of Vibrio parahaemolyticus strains isolated from cutting board surfaces in retail seafood markets.}, journal = {Journal of applied microbiology}, volume = {135}, number = {8}, pages = {}, doi = {10.1093/jambio/lxae182}, pmid = {39020257}, issn = {1365-2672}, support = {SCU.VF99.245//Shahid Chamran University of Ahvaz/ ; }, mesh = {*Vibrio parahaemolyticus/physiology/isolation &amp; purification ; *Biofilms/growth &amp; development ; *Seafood/microbiology ; Plasma Gases/pharmacology ; Food Microbiology ; Plankton/physiology ; Stainless Steel ; }, abstract = {AIMS: This research aimed to analyze cutting board surfaces in seafood markets to find Vibrio parahaemolyticus, assess the isolates' ability to form biofilms, generate and evaluate characteristics of plasma-activated water (PAW), and compare the effect of PAW on planktonic and biofilm cells of the isolated V. parahaemolyticus strains.<br><br>METHODS AND RESULTS: A total of 11&#xa0;V. parahaemolyticus strains were isolated from 8.87% of the examined cutting boards. Biofilm-forming ability was evaluated for these isolates at temperatures of 10&#xb0;C, 20&#xb0;C, and 30&#xb0;C using crystal violet staining. Four strains with the highest biofilm potential were selected for further analysis. The pH of the PAW used in the study was 3.41&#xa0;&#xb1;&#xa0;0.04, and the initial concentrations of hydrogen peroxide, nitrate, and nitrite were 108&#xa0;&#xb1;&#xa0;9.6, 742&#xa0;&#xb1;&#xa0;61, and 36.3&#xa0;&#xb1;&#xa0;2.9&#xa0;&#xb5;M, respectively. However, these concentrations decreased significantly within 3-4 days during storage at room temperature. PAW exhibited significant antimicrobial effects on V. parahaemolyticus planktonic cells, reducing viable bacteria up to 4.54 log CFU/ml within 20 min. PAW also reduced the number of biofilm cells on stainless steel (up to 3.55 log CFU/cm2) and high-density polyethylene (up to 3.06 log CFU/cm2) surfaces, although to a lesser extent than planktonic cells.<br><br>CONCLUSIONS: PAW exhibited significant antibacterial activity against V. parahaemolyticus cells, although its antibacterial properties diminished over time. Furthermore, the antibacterial activity of PAW against biofilm cells of V. parahaemolyticus was less pronounced compared to the planktonic cells. Therefore, the actual effectiveness of PAW in seafood processing environments can be affected by biofilms that may form on various surfaces such as cutting boards if they are not cleaned properly.}, }
@article {pmid39020245, year = {2024}, author = {Huang, Z and Li, Y and Yin, W and Raby, RBN and Liang, H and Yu, B}, title = {A magnetic-guided nano-antibacterial platform for alternating magnetic field controlled vancomycin release in staphylococcus aureus biofilm eradication.}, journal = {Drug delivery and translational research}, volume = {}, number = {}, pages = {}, pmid = {39020245}, issn = {2190-3948}, support = {81974323//National Natural Science Foundation of China/ ; 2020A1515010055//Natural Science Foundation of Guangdong Province/ ; zdyf201993//Science and Technology Development Plan Project of Chenzhou/ ; }, abstract = {Bacterial resilience within biofilms, rendering them up to 1000 times more resistant to antibiotic drugs, poses a formidable challenge. This study introduces a targeted biofilm eradication strategy, termed "target-penetration-killing-eradication", implemented through magnetic micro-robotic technology. Specifically, we present the development of a magnetic-guided nano-antibacterial platform designed for alternating magnetic field (AMF) controlled vancomycin release in the eradication of Staphylococcus aureus biofilms. To address the issue of premature vancomycin release in physiological conditions, we employed a temperature-sensitive linking agent, 4,4'-azobis(4-cyano valeric acid), facilitating the conjugation of vancomycin onto Fe3O4/CS nanocomposites, resulting in the novel construct Fe3O4@CS-ACVA-VH. The release mechanism adheres to first-order kinetics and Fickian diffusion, with each 10-min AMF treatment releasing approximately 8.4 ± 1.1% of vancomycin. The potency of vancomycin in the release solution was similar to that of the original drug (MIC: 7.4 ± 3.5 vs. 5.6 μg/mL). Fe3O4@CS-ACVA-VH exhibited sustained antibacterial efficacy, inhibiting bacterial growth for four consecutive days and preventing the formation of bacterial biofilms on its surface. Contact-inhibition bacterial activity of Fe3O4@CS-ACVA-VH against S. aureus was 0.046875 mg/mL. Conceptually validating our approach, we emphasize Fe3O4@CS-ACVA-VH's exceptional ability to penetrate S. aureus biofilms under static magnetic field attraction. Furthermore, the nano-platform offers the unique advantage of on-demand vancomycin release through alternating magnetic field stimulation, effectively clearing a larger biofilm area. This multifunctional nano-platform demonstrates magnetic-guided biofilm penetration followed by controlled vancomycin release, presenting a promising strategy for enhanced biofilm eradication.}, }
@article {pmid39019725, year = {2024}, author = {Bueno, FL and Badaró, MM and Pagnano, VO and Curylofo, PA and Oliveira, VC and Macedo, AP and Watanabe, E and Paranhos, HFO and Silva-Lovato, CH}, title = {Effect of disinfectants on multispecies biofilm, the physical and mechanical properties of polymethyl methacrylate, and the corrosion of cobalt chromium alloy.}, journal = {The Journal of prosthetic dentistry}, volume = {132}, number = {3}, pages = {603.e1-603.e8}, doi = {10.1016/j.prosdent.2024.06.019}, pmid = {39019725}, issn = {1097-6841}, mesh = {*Polymethyl Methacrylate/chemistry ; *Biofilms/drug effects ; *Chromium Alloys/chemistry ; Corrosion ; *Surface Properties ; Materials Testing ; Sodium Hypochlorite/pharmacology ; Microscopy, Electron, Scanning ; Hardness ; In Vitro Techniques ; Disinfectants/pharmacology ; Humans ; Flexural Strength ; }, abstract = {STATEMENT OF PROBLEM: The optimal disinfection protocol that controls adverse effects and promotes effective antimicrobial action on removable prostheses is unclear.<br><br>PURPOSE: This in vitro study investigated the effect of disinfectant solutions on the biological, physical, mechanical, and chemical properties of removable prosthesis materials.<br><br>MATERIAL AND METHODS: Specimens of polymethyl methacrylate (PMMA) and cobalt chromium (Co-Cr) alloy were immersed in distilled water (PMMA) or artificial saliva (Co-Cr) as the control and in 0.25% sodium hypochlorite (NaOCl0.25%), 0.5% chloramine T (CT0.5%), and 0.15% Triclosan (TR0.15%). The antibiofilm activity was evaluated by microbial load and cell metabolisms of the mixed biofilm. Physical (color change, sorption, solubility, and surface roughness), mechanical (hardness, flexural, and impact strength), and chemical (corrosion) properties were analyzed before and after simulating a 5-year immersion. Laser confocal microscopy, scanning electron microscopy (SEM), and dispersive energy spectroscopy (EDS) complemented the analyses. The data were analyzed by using the Mann-Whitney U test, Kruskal-Wallis with Dunn posttests, 1-way ANOVA, and repeated measures ANOVA (&#x3b1;=.05).<br><br>RESULTS: All solutions were effective against bacteria, but only NaOCl0.25% eliminated Candida spp. TR0.15%, and CT0.5% increased cell metabolisms. For interaction (time and solution), there was a reduction in PMMA hardness in the control and TR0.15%. Color, sorption, solubility, and flexural strength did not change. CT0.5% and TR0.15% were similar for impact resistance. CT0.5% caused the lowest roughness. NaOCl0.25% showed the greatest corrosive potential. Dark spots were seen under SEM in Co-Cr stored with NaOCl0.25% and TR0.15%. EDS indicated different proportions of oxygen, cobalt, chromium, and molybdenum.<br><br>CONCLUSIONS: NaOCl0.25% had the best antimicrobial action. CT0.5% and TR0.15% have potential. Hardness and roughness changes were clinically acceptable, and the other properties remained unchanged. All the solutions caused color changes. NaOCl0.25% was unsatisfactory for use with Co-Cr, CT0.5% was intermediate, and TR0.15% was suitable.}, }
@article {pmid39019323, year = {2024}, author = {Siu, SY and Pudipeddi, A and Vishwanath, V and Cheng Lee, AH and Tin Cheung, AW and Pan Cheung, GS and Neelakantan, P}, title = {Effect of Novel and Traditional Intracanal Medicaments on Biofilm Viability and Composition.}, journal = {Journal of endodontics}, volume = {50}, number = {10}, pages = {1412-1419}, doi = {10.1016/j.joen.2024.07.003}, pmid = {39019323}, issn = {1878-3554}, mesh = {*Biofilms/drug effects ; *Enterococcus faecalis/drug effects ; *Actinomyces/drug effects ; Calcium Hydroxide/pharmacology ; Microbial Viability/drug effects ; Root Canal Irrigants/pharmacology ; Amino Acids/pharmacology ; Humans ; }, abstract = {INTRODUCTION: The aim of this study was to test the hypothesis that a combination of D-amino acids (DAAs) and trans-cinnamaldehyde (TC) demonstrates superior antibiofilm activity to calcium hydroxide (CH) and untreated controls.<br><br>METHODS: In this 3-part in&#xa0;vitro study, the concentration of DAAs (D-methionine, D-leucine, D-tyrosine, and D-tryptophan) that would significantly decrease Enterococcus faecalis and Actinomyces naeslundii biofilm biomass was first determined. Then, the effect of TC&#xa0;+ selected DAAs on polymicrobial biofilms was characterized by quantifying the biomass and biofilm viability. Finally, the antibiofilm effects of TC&#xa0;+&#xa0;DAA was compared with CH and untreated controls by (i) determining bacterial viability and (ii) quantifying biofilm matrix composition using selective fluorescence-binding analysis. Statistical analysis was performed using one-way ANOVA and appropriate multiple comparisons test, with P&#xa0;<&#xa0;.05 considered as statistically significant.<br><br>RESULTS: TC (0.06%)&#xa0;+ D-tyrosine (1&#xa0;mM)&#xa0;+&#xa0;D-tryptophan (25&#xa0;mM) significantly reduced the biomass and biofilm viability compared to the control (P&#xa0;<&#xa0;.05). While no significant difference was observed between TC&#xa0;+&#xa0;DAA and CH in the cultivable bacterial counts (P&#xa0;>&#xa0;.05), confocal microscopy demonstrated a significantly greater percentage of dead bacteria in TC&#xa0;+&#xa0;DAA-treated biofilms compared to CH and the control (P&#xa0;<&#xa0;.05). TC&#xa0;+&#xa0;DAA significantly decreased the biovolume and all the examined components of the biofilm matrix quantity compared to the control, while CH significantly reduced only the exopolysaccharide quantity (P&#xa0;<&#xa0;.05).<br><br>CONCLUSION: The combination of TC&#xa0;+&#xa0;D-tyrosine&#xa0;+&#xa0;D-tryptophan demonstrated superior antibiofilm activity (biofilm bacterial killing and reduction of matrix quantity) to CH and has potential to be developed as an intracanal medicament.}, }
@article {pmid39017726, year = {2024}, author = {Carvalho, FS and Tarabal, VS and Livio, DF and Cruz, LF and Monteiro, APF and Parreira, AG and Guimarães, PPG and Scheuerman, K and Chagas, RCR and da Silva, JA and Gonçalves, DB and Granjeiro, JM and Sinisterra, RD and Segura, MEC and Granjeiro, PA}, title = {Production and characterization of the lipopeptide with anti-adhesion for oral biofilm on the surface of titanium for dental implants.}, journal = {Archives of microbiology}, volume = {206}, number = {8}, pages = {354}, pmid = {39017726}, issn = {1432-072X}, support = {APQ- 00855-19//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado de Minas Gerais/ ; 306076/2017-9//Conselho Nacional de Desenvolvimento Cient&#xed;fico e Tecnol&#xf3;gico/ ; 001//Coordena&#xe7;&#xe3;o de Aperfei&#xe7;oamento de Pessoal de N&#xed;vel Superior/ ; }, mesh = {*Titanium/pharmacology/chemistry ; *Biofilms/drug effects/growth &amp; development ; *Bacterial Adhesion/drug effects ; *Dental Implants/microbiology ; *Lipopeptides/pharmacology ; *Microbial Sensitivity Tests ; Humans ; Anti-Bacterial Agents/pharmacology ; Staphylococcus aureus/drug effects/physiology ; Bacillus subtilis/drug effects ; Porphyromonas gingivalis/drug effects/physiology/growth &amp; development ; Aggregatibacter actinomycetemcomitans/drug effects ; Surface Properties ; Fibroblasts/drug effects ; Fusobacterium nucleatum/drug effects ; Cell Survival/drug effects ; Osteoblasts/drug effects ; Surface-Active Agents/pharmacology ; }, abstract = {Titanium implants are subject to bacterial adhesion and peri-implantitis induction, and biosurfactants bring a new alternative to the fight against infections. This work aimed to produce and characterize the biosurfactant from Bacillus subtilis ATCC 19,659, its anti-adhesion and antimicrobial activity, and cell viability. Anti-adhesion studies were carried out against Streptococcus sanguinis, Staphylococcus aureus, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Proteus mirabilis as the minimum inhibitory concentration and the minimum bactericidal concentration. Cell viability was measured against osteoblast and fibroblast cells. The biosurfactant was classified as lipopeptide, with critical micelle concentration at 40 µg mL[- 1], and made the titanium surface less hydrophobic. The anti-adhesion effect was observed for Staphylococcus aureus and Streptococcus sanguinis with 54% growth inhibition and presented a minimum inhibitory concentration of 15.7 µg mL[- 1] for Streptococcus sanguinis and Aggregatibacter actinomycetemcomitans. The lipopeptide had no cytotoxic effect and demonstrated high potential application against bacterial biofilms.}, }
@article {pmid39015665, year = {2024}, author = {Tian, Z and Xiong, Y and Li, G and Cao, X and Li, X and Du, C and Zhang, L}, title = {Food wastewater treatment using a hybrid biofilm reactor: nutrient removal performance and functional microorganisms on filler biofilm and suspended sludge.}, journal = {RSC advances}, volume = {14}, number = {31}, pages = {22470-22479}, pmid = {39015665}, issn = {2046-2069}, abstract = {In this study, a laboratory-scale hybrid biofilm reactor (HBR) was constructed to treat food wastewater (FWW) before it is discharged into the sewer. The chemical oxygen demand (COD) of 29 860 mg L[-1] in FWW was degraded to 200-350 mg L[-1] using the HBR under the operating parameters of COD load 1.68 kg m[-3] d[-1], hydraulic retention time (HRT) of 426.63 h, dissolved oxygen (DO) of 8-9 mg L[-1], and temperature of 22-23 °C. The biomass of biofilm on the surface of filler was 2.64 g L[-1] for column A and 0.91 g L[-1] for column O. Microbial analysis revealed richer and more diverse microorganisms in filler biofilms compared to those in suspended sludge. The hybrid filler was conducive to the development of functional microbial species, including phyla Firmicutes, Actinobacteriota, and Chloroflexi, and genus level norank_f_JG30-KF-CM45, which will improve FWW treatment efficiency. Moreover, the microorganisms on the filler biofilm had more connections and relationships than those in the suspended sludge. The combination of an up-flow anaerobic sludge bed (UASB) and HBR was demonstrated to be an economical strategy for practical applications as a shorter HRT of 118.34 h could be obtained. Overall, this study provides reliable data and a theoretical basis for the application of HBR and FWW treatments.}, }
@article {pmid39014985, year = {2024}, author = {Duggan DiDominic, KL and Shapleigh, JP and Walter, MT and Wang, YS and Reid, MC and Regan, JM}, title = {Microbial diversity and gene abundance in denitrifying bioreactors: A comparison of the woodchip surface biofilm versus the interior wood matrix.}, journal = {Journal of environmental quality}, volume = {53}, number = {5}, pages = {565-576}, doi = {10.1002/jeq2.20600}, pmid = {39014985}, issn = {1537-2537}, support = {1922551//National Science Foundation Research Traineeship (NRT) Program/ ; 2019-67019-29461//U.S. Department of Agriculture/ ; }, mesh = {*Bioreactors ; *Wood ; *Biofilms ; *Denitrification ; Microbiota ; Nitrogen/analysis ; Bacteria/genetics/metabolism ; }, abstract = {Excessive amounts of nitrogen (N) and phosphorus (P) can lead to eutrophication in water sources. Woodchip bioreactors have shown success in removing N from agricultural runoff, but less is known regarding P removal. Woodchip bioreactors are subsurface basins filled with woodchips installed downgradient of agricultural land to collect and treat drainage runoff. Microorganisms use the woodchips as a carbon (C) source to transform N in the runoff, with unresolved biological impacts on P. This study aims to explore microbial communities present in the bioreactor and determine whether milling woodchips to probe the microbial communities within them reveals hidden microbial diversities or potential activities. Metagenomic sequencing and bioinformatic analyses were performed on six woodchip samples (i.e., three unmilled and three milled) collected from a 10-year-old woodchip bioreactor treating agricultural tile drainage. All samples had similar DNA purity, yield, quality, and microbial diversity regardless of milling. However, when sequences were aligned against various protein libraries, our results indicated greater relative abundance of denitrification and P transformation proteins on the outside of the woodchips (unmilled), while the interior of woodchips (milled) exhibited more functional gene abundance for carbohydrate breakdown. Thus, it may be important to characterize microbial communities both within woodchips, and on woodchip surfaces, to gain a more holistic understanding of coupled biogeochemical cycles on N, P, and C in woodchip bioreactors. Based on these findings, we advise that future microbial research on woodchips (and potentially other permeable organic materials) examine both the surface biofilm and the interior organic material during initial studies. Once researchers determine where specific proteins or enzymes of interest are most prevalent, subsequent studies may then focus on either one or both aspects, as needed.}, }
@article {pmid39012538, year = {2024}, author = {Tang, D and Lin, Y and Yao, H and Liu, Y and Xi, Y and Li, M and Mao, A}, title = {Effect of L-HSL on biofilm and motility of Pseudomonas aeruginosa and its mechanism.}, journal = {Applied microbiology and biotechnology}, volume = {108}, number = {1}, pages = {418}, pmid = {39012538}, issn = {1432-0614}, support = {12065001//12065001/ ; 32160025//32160025/ ; }, mesh = {*Pseudomonas aeruginosa/drug effects/physiology/genetics ; *Biofilms/drug effects/growth &amp; development ; *Quorum Sensing/drug effects ; *Caenorhabditis elegans/drug effects/microbiology ; Animals ; *4-Butyrolactone/analogs &amp; derivatives/pharmacology/metabolism ; Anti-Bacterial Agents/pharmacology ; Gene Expression Profiling ; Homoserine/analogs &amp; derivatives/metabolism/pharmacology ; Gene Expression Regulation, Bacterial/drug effects ; }, abstract = {Pseudomonas aeruginosa (P. aeruginosa) biofilm formation is a crucial cause of enhanced antibiotic resistance. Quorum sensing (QS) is involved in regulating biofilm formation; QS inhibitors block the QS signaling pathway as a new strategy to address bacterial resistance. This study investigated the potential and mechanism of L-HSL (N-(3-cyclic butyrolactone)-4-trifluorophenylacetamide) as a QS inhibitor for P. aeruginosa. The results showed that L-HSL effectively inhibited the biofilm formation and dispersed the pre-formed biofilm of P. aeruginosa. The production of extracellular polysaccharides and the motility ability of P. aeruginosa were suppressed by L-HSL. C. elegans infection experiment showed that L-HSL was non-toxic and provided protection to C. elegans against P. aeruginosa infection. Transcriptomic analysis revealed that L-HSL downregulated genes related to QS pathways and biofilm formation. L-HSL exhibits a promising potential as a therapeutic drug for P. aeruginosa infection. KEY POINTS: • Chemical synthesis of N-(3-cyclic butyrolactone)-4-trifluorophenylacetamide, named L-HSL. • L-HSL does not generate survival pressure on the growth of P. aeruginosa and can inhibit the QS system. • KEGG enrichment analysis found that after L-HSL treatment, QS-related genes were downregulated.}, }
@article {pmid39012148, year = {2024}, author = {Ayala, JC and Balthazar, JT and Shafer, WM}, title = {Transcriptional responses of Neisseria gonorrhoeae to glucose and lactate: implications for resistance to oxidative damage and biofilm formation.}, journal = {mBio}, volume = {15}, number = {8}, pages = {e0176124}, pmid = {39012148}, issn = {2150-7511}, support = {R01 AI021150/AI/NIAID NIH HHS/United States ; R24 AI155395/AI/NIAID NIH HHS/United States ; IK6 BX005390/BX/BLRD VA/United States ; AI021150-37//HHS | NIH | National Institute of Allergy and Infectious Diseases (NIAID)/ ; R37 AI021150/AI/NIAID NIH HHS/United States ; }, mesh = {*Neisseria gonorrhoeae/genetics/metabolism/drug effects/physiology ; *Biofilms/growth &amp; development ; *Lactic Acid/metabolism ; *Glucose/metabolism ; *Oxidative Stress ; *Gene Expression Regulation, Bacterial ; *Iron/metabolism ; Gonorrhea/microbiology ; Gene Expression Profiling ; }, abstract = {Understanding how bacteria adapt to different environmental conditions is crucial for advancing knowledge regarding pathogenic mechanisms that operate during infection as well as efforts to develop new therapeutic strategies to cure or prevent infections. Here, we investigated the transcriptional response of Neisseria gonorrhoeae, the causative agent of gonorrhea, to L-lactate and glucose, two important carbon sources found in the host environment. Our study revealed extensive transcriptional changes that gonococci make in response to L-lactate, with 37% of the gonococcal transcriptome being regulated, compared to only 9% by glucose. We found that L-lactate induces a transcriptional program that would negatively impact iron transport, potentially limiting the availability of labile iron, which would be important in the face of the multiple hydrogen peroxide attacks encountered by gonococci during its lifecycle. Furthermore, we found that L-lactate-mediated transcriptional response promoted aerobic respiration and dispersal of biofilms, contrasting with an anaerobic condition previously reported to favor biofilm formation. Our findings suggest an intricate interplay between carbon metabolism, iron homeostasis, biofilm formation, and stress response in N. gonorrhoeae, providing insights into its pathogenesis and identifying potential therapeutic targets.IMPORTANCEGonorrhea is a prevalent sexually transmitted infection caused by the human pathogen Neisseria gonorrhoeae, with ca. 82 million cases reported worldwide annually. The rise of antibiotic resistance in N. gonorrhoeae poses a significant public health threat, highlighting the urgent need for alternative treatment strategies. By elucidating how N. gonorrhoeae responds to host-derived carbon sources such as L-lactate and glucose, this study offers insights into the metabolic adaptations crucial for bacterial survival and virulence during infection. Understanding these adaptations provides a foundation for developing novel therapeutic approaches targeting bacterial metabolism, iron homeostasis, and virulence gene expression. Moreover, the findings reported herein regarding biofilm formation and L-lactate transport and metabolism contribute to our understanding of N. gonorrhoeae pathogenesis, offering potential avenues for preventing and treating gonorrhea infections.}, }
@article {pmid39012136, year = {2024}, author = {Motta, EVS and de Jong, TK and Gage, A and Edwards, JA and Moran, NA}, title = {Glyphosate effects on growth and biofilm formation in bee gut symbionts and diverse associated bacteria.}, journal = {Applied and environmental microbiology}, volume = {90}, number = {8}, pages = {e0051524}, pmid = {39012136}, issn = {1098-5336}, support = {R35 GM131738/GM/NIGMS NIH HHS/United States ; //Texas A and M University (A&amp;M)/ ; R35GM131738//HHS | National Institutes of Health (NIH)/ ; }, mesh = {Animals ; *Glyphosate ; *Biofilms/drug effects/growth &amp; development ; Bees/microbiology ; *Glycine/analogs &amp; derivatives/pharmacology ; *Gastrointestinal Microbiome/drug effects ; *Herbicides/pharmacology ; *Bacteria/drug effects/growth &amp; development ; *Symbiosis ; Bacterial Physiological Phenomena/drug effects ; }, abstract = {UNLABELLED: Biofilm formation is a common adaptation enabling bacteria to thrive in various environments and withstand external pressures. In the context of host-microbe interactions, biofilms play vital roles in establishing microbiomes associated with animals and plants and are used by opportunistic microbes to facilitate survival within hosts. Investigating biofilm dynamics, composition, and responses to environmental stressors is crucial for understanding microbial community assembly and biofilm regulation in health and disease. In this study, we explore in vivo colonization and in vitro biofilm formation abilities of core members of the honey bee (Apis mellifera) gut microbiota. Additionally, we assess the impact of glyphosate, a widely used herbicide with antimicrobial properties, and a glyphosate-based herbicide formulation on growth and biofilm formation in bee gut symbionts as well as in other biofilm-forming bacteria associated with diverse animals and plants. Our results demonstrate that several strains of core bee gut bacterial species can colonize the bee gut, which probably depends on their ability to form biofilms. Furthermore, glyphosate exposure elicits variable effects on bacterial growth and biofilm formation. In some instances, the effects correlate with the bacteria's ability to encode a susceptible or tolerant version of the enzyme inhibited by glyphosate in the shikimate pathway. However, in other instances, no such correlation is observed. Testing the herbicide formulation further complicates comparisons, as results often diverge from glyphosate exposure alone, suggesting that co-formulants influence bacterial growth and biofilm formation. These findings highlight the nuanced impacts of environmental stressors on microbial biofilms, with both ecological and host health-related implications.<br><br>IMPORTANCE: Biofilms are essential for microbial communities to establish and thrive in diverse environments. In the honey bee gut, the core microbiota member Snodgrassella alvi forms biofilms, potentially aiding the establishment of other members and promoting interactions with the host. In this study, we show that specific strains of other core members, including Bifidobacterium, Bombilactobacillus, Gilliamella, and Lactobacillus, also form biofilms in vitro. We then examine the impact of glyphosate, a widely used herbicide that can disrupt the bee microbiota, on bacterial growth and biofilm formation. Our findings demonstrate the diverse effects of glyphosate on biofilm formation, ranging from inhibition to enhancement, reflecting observations in other beneficial or pathogenic bacteria associated with animals and plants. Thus, glyphosate exposure may influence bacterial growth and biofilm formation, potentially shaping microbial establishment on host surfaces and impacting health outcomes.}, }
@article {pmid39012102, year = {2024}, author = {Conway, J and Delanois, RE and Mont, MA and Stavrakis, A and McPherson, E and Stolarski, E and Incavo, S and Oakes, D and Salvagno, R and Adams, JS and Kisch-Hancock, A and Tenorio, E and Leighton, A and Ryser, S and Kauvar, LM and Bernthal, NM}, title = {Phase 1 study of the pharmacokinetics and clinical proof-of-concept activity of a biofilm-disrupting human monoclonal antibody in patients with chronic prosthetic joint infection of the knee or hip.}, journal = {Antimicrobial agents and chemotherapy}, volume = {68}, number = {8}, pages = {e0065524}, pmid = {39012102}, issn = {1098-6596}, support = {/WT_/Wellcome Trust/United Kingdom ; 27302C0028/ES/NIEHS NIH HHS/United States ; 4500004431//Combating Antibiotic-Resistant Bacteria Biopharmaceutical Accelerator (CARB-X)/ ; }, mesh = {Humans ; *Biofilms/drug effects ; *Prosthesis-Related Infections/drug therapy/microbiology ; Female ; Male ; Middle Aged ; Aged ; *Anti-Bacterial Agents/pharmacokinetics/therapeutic use/pharmacology ; Double-Blind Method ; *Antibodies, Monoclonal/pharmacokinetics/therapeutic use/pharmacology ; }, abstract = {UNLABELLED: We report the results of a first-in-human phase 1 clinical study to evaluate TRL1068, a native human monoclonal antibody that disrupts bacterial biofilms with broad-spectrum activity against both Gram-positive and Gram-negative species. The study population consisted of patients with chronic periprosthetic joint infections (PJIs) of the knee or hip, including both monomicrobial and polymicrobial infections, that are highly resistant to antibiotics due to biofilm formation. TRL1068 was administered via a single pre-surgical intravenous infusion in three sequentially ascending dose groups (6, 15, and 30 mg/kg). Concomitant perioperative antibiotics were pathogen-targeted as prescribed by the treating physician. In this double-blinded study, 4 patients were randomized to receive placebo and 11 patients to receive TRL1068 on day 1, as well as targeted antibiotics for 7 days prior to the scheduled removal of the infected implant and placement of an antibiotic-eluting spacer as the first stage of the standard of care two-stage exchange arthroplasty. No adverse events attributable to TRL1068 were reported. TRL1068 serum half-life was 15-18 days. At day 8, the concentration in synovial fluid was approximately 60% of the blood level and thus at least 15-fold above the threshold for biofilm-disrupting activity in vitro. Explanted prostheses were sonicated to release adherent bacteria for culture, with elimination of the implant bacteria observed in 3 of the 11 patients who received TRL1068, which compares favorably to prior PJI treatments. None of the patients who received TRL1068 had a relapse of the original infection by the end of the study (day 169).<br><br>CLINICAL TRIALS: This study is registered with ClinicalTrials.gov as NCT04763759.}, }
@article {pmid39011568, year = {2024}, author = {Martins, PHR and Romo, AIB and Gouveia, FS and Paz, IA and Nascimento, NRF and Andrade, AL and Rodríguez-López, J and de Vasconcelos, MA and Teixeira, EH and Moraes, CAF and Lopes, LGF and Sousa, EHS}, title = {Anti-bacterial, anti-biofilm and synergistic effects of phenazine-based ruthenium(II) complexes.}, journal = {Dalton transactions (Cambridge, England : 2003)}, volume = {53}, number = {30}, pages = {12627-12640}, doi = {10.1039/d4dt01033g}, pmid = {39011568}, issn = {1477-9234}, mesh = {*Phenazines/chemistry/pharmacology ; *Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; *Ruthenium/chemistry/pharmacology ; *Biofilms/drug effects ; *Coordination Complexes/chemistry/pharmacology/chemical synthesis ; *Microbial Sensitivity Tests ; Drug Synergism ; Staphylococcus aureus/drug effects ; }, abstract = {Antimicrobial resistance has become a global threat to human health, which is coupled with the lack of novel drugs. Metallocompounds have emerged as promising diverse scaffolds for the development of new antibiotics. Herein, we prepared some metal compounds mainly focusing on cis-[Ru(bpy)(dppz)(SO3)(NO)](PF6) (PR02, bpy = 2,2'-bipyridine, dppz = dipyrido[3,2-a:2',3'-c]phenazine), in which phenazinic and nitric oxide ligands along with sulfite conferred some key properties. This compound exhibited a redox potential for bound NO[+/0] of -0.252 V (vs. Ag|AgCl) and a high pH for nitrosyl-nitro conversion of 9.16, making the nitrosyl ligand the major species. These compounds were still able to bind to DNA structures. Interestingly, reduced glutathione (GSH) was unable to promote significant NO/HNO release, an uncommon feature of many similar systems. However, this reducing agent was essential to generate superoxide radicals. Antimicrobial studies were carried out using six bacterial strains, where none or very low activity was observed for Gram-negative bacteria. However, PR02 and PR (cis-[Ru(bpy)(dppz)Cl2]) showed high antibacterial activity in some Gram-positive strains (MBC for S. aureus up to 4.9 μmol L[-1]), where the activity of PR02 was similar to or at least 4-fold better than that of PR. Besides, PR02 showed capacity to inhibit bacterial biofilm formation, a major health issue leading to bacterial tolerance to antibiotics. Interestingly, we also showed that PR02 can function in synergism with the known antibiotic ampicillin, improving their action up to 4-fold even against resistant strains. Altogether, these results showed that PR02 is a promising antimicrobial nitrosyl ruthenium compound combining features beyond its killing action, which deserves further biological studies.}, }
@article {pmid39011151, year = {2024}, author = {Macià, MD and Borghi, E and Oliver, A}, title = {Eurobiofilms 2022: A translational perspective of biofilm-related persistent infections.}, journal = {Biofilm}, volume = {7}, number = {}, pages = {100168}, pmid = {39011151}, issn = {2590-2075}, }
@article {pmid39010993, year = {2024}, author = {El-Subeyhi, M and Hamid, LL and Gayadh, EW and Saod, WM and Ramizy, A}, title = {Biogenic Synthesis and Characterisation of Novel Potassium Nanoparticles by Capparis spinosa Flower Extract and Evaluation of Their Potential Antibacterial, Anti-biofilm and Antibiotic Development.}, journal = {Indian journal of microbiology}, volume = {64}, number = {2}, pages = {548-557}, pmid = {39010993}, issn = {0046-8991}, abstract = {Scientific researches on the synthesis, characterisation, and biological activity of potassium nanoparticles (K NPs) are extremely rare. In our study, we successfully synthesised a novel form of K NPs using Capparis spinosa (C. spinosa) flower extract as a reducing and capping agent. The formation of K NPs in new form (K2O NPs) was confirmed by UV-vis and XRD spectra. Furthermore, the FTIR results indicated the presence of specific active biomolecules in the C. spinosa extract which played a crucial role in reducing and stabilising K2O NPs. SEM imaging demonstrated that the K2O NPs exhibited irregular shapes with nanosizes ranging between 25 and 95 nm. Remarkably, the biosynthesised K2O NPs displayed considerable antibacterial activity against a wide range of multidrug-resistant (MDR) pathogenic bacteria. K2O NPs demonstrated considerable anti-biofilm activity against preformed biofilms produced by MDR bacteria. Combining K2O NPs with conventional antibiotics greatly improved their efficacy in compacting the MDR bacterial strains. Industrially, bulk form of potassium oxides was commonly used in the preparation of various antimicrobial compounds such as detergents, bleach, and oxidising solutions. The synthesis of potassium oxide in nanoform has shown remarkable biological efficacy, making it a promising therapeutic approach for pharmaceutical and medical applications.}, }
@article {pmid39009474, year = {2025}, author = {Mahto, KU and Das, S}, title = {Electroactive biofilm communities in microbial fuel cells for the synergistic treatment of wastewater and bioelectricity generation.}, journal = {Critical reviews in biotechnology}, volume = {45}, number = {2}, pages = {434-453}, doi = {10.1080/07388551.2024.2372070}, pmid = {39009474}, issn = {1549-7801}, mesh = {*Bioelectric Energy Sources/microbiology ; *Biofilms/growth &amp; development ; *Wastewater/microbiology ; Electron Transport ; Electricity ; Water Purification/methods ; Bacteria/metabolism ; }, abstract = {Increasing industrialization and urbanization have contributed to a significant rise in wastewater discharge and exerted extensive pressure on the existing natural energy resources. Microbial fuel cell (MFC) is a sustainable technology that utilizes wastewater for electricity generation. MFC comprises a bioelectrochemical system employing electroactive biofilms of several aerobic and anaerobic bacteria, such as Geobacter sulfurreducens, Shewanella oneidensis, Pseudomonas aeruginosa, and Ochrobacterum pseudiintermedium. Since the electroactive biofilms constitute a vital part of the MFC, it is crucial to understand the biofilm-mediated pollutant metabolism and electron transfer mechanisms. Engineering electroactive biofilm communities for improved biofilm formation and extracellular polymeric substances (EPS) secretion can positively impact the bioelectrochemical system and improve fuel cell performance. This review article summarizes the role of electroactive bacterial communities in MFC for wastewater treatment and bioelectricity generation. A significant focus has been laid on understanding the composition, structure, and function of electroactive biofilms in MFC. Various electron transport mechanisms, including direct electron transfer (DET), indirect electron transfer (IET), and long-distance electron transfer (LDET), have been discussed. A detailed summary of the optimization of process parameters and genetic engineering strategies for improving the performance of MFC has been provided. Lastly, the applications of MFC for wastewater treatment, bioelectricity generation, and biosensor development have been reviewed.}, }
@article {pmid39009090, year = {2024}, author = {Li, X and Xiao, L and Sui, X and Li, M and Wang, N and Sun, Z and Li, T and Cao, X and Li, B}, title = {Municipal solid waste leachate treatment by three-stage membrane aeration biofilm reactor system.}, journal = {Chemosphere}, volume = {363}, number = {}, pages = {142847}, doi = {10.1016/j.chemosphere.2024.142847}, pmid = {39009090}, issn = {1879-1298}, mesh = {*Biofilms ; *Bioreactors/microbiology ; *Nitrogen ; *Water Pollutants, Chemical/analysis/metabolism ; *Biological Oxygen Demand Analysis ; *Ammonia/analysis ; Solid Waste/analysis ; Bacteria/metabolism ; Waste Disposal, Fluid/methods ; Denitrification ; }, abstract = {A combined process of coagulation pretreatment and three-stage membrane aeration biofilm reactor (MABR) system was successfully applied for the first time to treat actual municipal solid waste leachate (MSWL), which was characterized by high concentrations of toxic hard-to-degrade organics and salinity. The results showed that 9.8%-21.3% of organics could be removed from actual MSWL by coagulation with polymeric aluminum chloride (PAC). Three-stage MABR contributed 95.6% of the chemical oxygen demand (COD) removal, with the influent COD concentration ranging from 6000 to 7000 mg/L. At the same time, the removal efficiencies of total nitrogen (TN) and ammonia (NH4[+]-N) could reach to 84.3% and 79.9% without the addition of external carbon source, respectively. The nitrifying/denitrifying bacteria were enriched in the biofilm including Thiobacillus, Azoarcus and Methyloversatilis, which supported the MABR with high nitrogen removal efficiency and significantly toxic tolerance. Principal component analysis (PCA) and the Pearson correlation coefficients (r) illustrated that aeration pressure is a crucial operational parameter, exhibiting a strong correlation between the MABR performance and microbial communities. This work demonstrates that MABR is an effective and low-energy option for simultaneous removal of carbon and nitrogen in the treatment of MSWL.}, }
@article {pmid39008846, year = {2024}, author = {Dey, R and Mukherjee, R and Biswas, S and Haldar, J}, title = {Stimuli-Responsive Release-Active Dressing: A Promising Solution for Eradicating Biofilm-Mediated Wound Infections.}, journal = {ACS applied materials &amp; interfaces}, volume = {16}, number = {29}, pages = {37795-37805}, doi = {10.1021/acsami.4c09820}, pmid = {39008846}, issn = {1944-8252}, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/chemistry/pharmacology ; *Bandages ; *Wound Infection/drug therapy/microbiology ; *Methicillin-Resistant Staphylococcus aureus/drug effects/physiology ; Animals ; Mice ; Hydrogen-Ion Concentration ; Staphylococcal Infections/drug therapy ; Microbial Sensitivity Tests ; Humans ; Carboxymethylcellulose Sodium/chemistry/pharmacology ; }, abstract = {Biofilm-mediated wound infections pose a significant challenge due to the limitations of conventional antibiotics, which often exhibit narrow-spectrum activity, fail to eliminate recurrent bacterial contamination, and are unable to penetrate the biofilm matrix. While the search for alternatives has explored the use of metal nanoparticles and synthetic biocides, these solutions often suffer from unintended toxicity to surrounding tissues and lack controlled administration and release. In this study, we engineered a pH-responsive release-active dressing film based on carboxymethyl cellulose, incorporating a synthetic antibacterial molecule (SAM-17). The dressing film exhibited optimal mechanical stability for easy application and demonstrated excellent fluid absorption properties, allowing for prolonged moisturization at the site of injury. The film exhibited pH-dependent release of cargo, with 78% release within 24 h at acidic pH, enabling targeted antibacterial drug delivery within the wound microenvironment. Furthermore, the release-active film effectively eliminated repeated challenges of bacterial contamination. Remarkably, the film demonstrated a minimal toxicity profile in both in vitro and in vivo models. The film eliminated preformed bacterial biofilms, achieving a reduction of 2.5 log against methicillin-resistant Staphylococcus aureus (MRSA) and 4.1 log against vancomycin-resistant S. aureus (VRSA). In a biofilm-mediated MRSA wound infection model, this release-active film eradicated the biofilm-embedded bacteria by over 99%, resulting in accelerated wound healing. These findings highlight the potential of this film as an effective candidate for tackling biofilm-associated wound infections.}, }
@article {pmid39003969, year = {2024}, author = {Jardak, M and Lami, R and Saadaoui, O and Jlidi, H and Stien, D and Aifa, S and Mnif, S}, title = {Control of Staphylococcus epidermidis biofilm by surfactins of an endophytic bacterium Bacillus sp. 15 F.}, journal = {Enzyme and microbial technology}, volume = {180}, number = {}, pages = {110477}, doi = {10.1016/j.enzmictec.2024.110477}, pmid = {39003969}, issn = {1879-0909}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Staphylococcus epidermidis/drug effects/physiology ; *Bacillus/physiology ; *Lipopeptides/pharmacology ; Anti-Bacterial Agents/pharmacology ; Endophytes/physiology/metabolism ; Bacterial Adhesion/drug effects ; Peptides, Cyclic/pharmacology ; }, abstract = {The present paper deals with the preparation and annotation of a surfactin(s) derived from a culture of the endophytic bacterium Bacillus 15 F. The LC-MS analysis of the acetonitrile fraction confirmed the presence of surfactins Leu/Ile7 C15, Leu/Ile7 C14 and Leu/Ile7 C13 with [M+H][+] at m/z 1036.6895, 1022.6741 and 1008.6581, respectively. Various concentrations of the surfactin(s) (hereafter referred to as surfactin-15 F) were used to reduce the adhesion of Staphylococcus epidermidis S61, which served as a model for studying antibiofilm activity on polystyrene surfaces. Incubation of Staphylococcus epidermidis S61 with 62.5 µg/ml of surfactin-15 F resulted in almost complete inhibition of biofilm formation (90.3 ± 3.33 %), and a significant reduction of cell viability (resazurin-based fluorescence was more than 200 times lower). The antiadhesive effect of surfactin-15 F was confirmed by scanning electron microscopy. Surfactin-15 F demonstrated an eradication effect against preformed biofilm, causing severe disruption of Staphylococcus epidermidis S61 biofilm structure and reducing viability. The results suggest that surfactins produced by endophytic bacteria could be an alternative to synthetic products. Surfactin-15 F, used in wound dressings, demonstrated an efficient treatment of the preformed Staphylococcus epidermidis S61 biofilm, and thus having a great potential in medical applications.}, }
@article {pmid39002458, year = {2024}, author = {Cao, J and Xu, A and Gao, D and Gong, X and Cheng, L and Zhou, Q and Yang, T and Gong, F and Liu, Z and Liang, H}, title = {Enhance PD/A biofilm formation via a novel biochar/tourmaline modified-biocarriers to treat low-strength contaminated surface water: Initial adhesion and high-substrate microenvironment.}, journal = {Journal of environmental management}, volume = {366}, number = {}, pages = {121803}, doi = {10.1016/j.jenvman.2024.121803}, pmid = {39002458}, issn = {1095-8630}, mesh = {*Biofilms ; *Charcoal/chemistry ; *Denitrification ; Nitrogen/chemistry ; Water Purification/methods ; }, abstract = {In this work, a novel polyurethane carrier modified with biochar and tourmaline/zeolite powder at ratio of 1:1 and 1:2 was developed to promote the formation of biofilms and the synergy of overall bacterial activity for Partial Denitrification/Anammox to treat low-nitrogen contaminated surface water. Based on the batch experiment, the modified biocarrier, BTP2 (biochar: tourmaline = 2: 1), exhibited the highest total nitrogen removal efficiency (83.63%) under influent total nitrogen of 15 mg/L and COD/NO3[-] of 3. The dense biofilm was formed in inner side of biocarrier owing to the increased surface roughness and various functional groups suggested by scanning electron microscopy and Fourier-transform infrared analysis. The EPS content increased from 200.15 to 220.26 mg/g VSS in BTP2 system. Besides, the rapid NH4[+] capture and organics release of the modified carrier fueled the growth of anammox and denitrification bacteria, with the activity of 2.13 ± 0.52 mg N/gVSS/h and 6.70 ± 0.52 mg N/gVSS/h (BTP2). High-throughput sequencing unraveled the increased abundances of Candidatus_Competibacter (0.82%), Thauera (0.60%) and Candidatus_Brocadia (0.55%) which was responsible for the synergy of incomplete reduction of NO3[-] to NO2[-] and NH4[+] oxidation. Overall, this study provided a valid and simple-control guide for biofilm formation towards rapid enrichment and great collaboration of Anammox and denitrification bacteria.}, }
@article {pmid39002428, year = {2024}, author = {Jyoti, K and Soni, K and Chandra, R}, title = {Pharmaceutical industrial wastewater exhibiting the co-occurrence of biofilm-forming genes in the multidrug-resistant bacterial community poses a novel environmental threat.}, journal = {Aquatic toxicology (Amsterdam, Netherlands)}, volume = {273}, number = {}, pages = {107019}, doi = {10.1016/j.aquatox.2024.107019}, pmid = {39002428}, issn = {1879-1514}, mesh = {*Biofilms/drug effects ; *Wastewater/microbiology ; *Drug Resistance, Multiple, Bacterial/genetics ; *Bacteria/genetics/drug effects ; *Anti-Bacterial Agents/toxicity/pharmacology ; Water Pollutants, Chemical/toxicity ; Industrial Waste ; Genes, Bacterial/genetics ; India ; Drug Industry ; Waste Disposal, Fluid ; }, abstract = {The interaction of the environment with the effluent of wastewater treatment plants, having antibiotics, multidrug-resistant (MDR) bacteria, and biofilm-forming genes (BFGs), has vast environmental risks. Antibiotic pollution bottlenecks environmental bacteria and has the potential to significantly lower the biodiversity of environmental bacteria, causing an alteration in ecological equilibrium. It can induce selective pressure for antibiotic resistance (AR) and can transform the non-resistant environmental bacteria into a resistant form through HGT. This study investigated the occurrence of MDR bacteria, showing phenotypic and genotypic characteristics of biofilm. The bacteria were isolated from the pharmaceutical wastewater treatment plants (WWTPs) of Dehradun and Haridwar (India), located in the pharmaceutical areas. The findings of this study demonstrate the coexistence of BFGs and MDR clinical bacteria in the vicinity of pharmaceutical industrial wastewater treatment plants. A total of 47 bacteria were isolated from both WWTPs and tested for antibiotic resistance to 13 different antibiotics; 16 isolates (34.04 %) tested positive for MDR. 5 (31.25 %) of these 16 MDR isolates were producing biofilm and identified as Pseudomonas aeruginosa, Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, and Burkholderia cepacia. The targeted BFGs in this study were ompA, bap and pslA. The most common co-occurring gene was ompA (80 %), with pslA (40 %) being the least common. A. baumannii contains all three targeted genes, whereas B. cepacia only has bap. Except for B. cepacia, all the biofilm-forming MDR isolates show AR to all the tested antibiotics and prove that the biofilm enhances the AR potential. The samples of both wastewater treatment plants also showed the occurrence of tetracycline, ampicillin, erythromycin and chloramphenicol, along with high levels of BOD, COD, PO4[-3], NO3[-], heavy metals and organic pollutants. The co-occurrence of MDR and biofilm-forming tendency in the clinical strain of bacteria and its environmental dissemination may have an array of hazardous impacts on human and environmental health.}, }
@article {pmid39000327, year = {2024}, author = {Mechmechani, S and Yammine, J and Alhuthali, S and El Mouzawak, M and Charvourou, G and Ghasrsallaoui, A and Chihib, NE and Doulgeraki, A and Karam, L}, title = {Study of the Resistance of Staphylococcus aureus Biofilm, Biofilm-Detached Cells, and Planktonic Cells to Microencapsulated Carvacrol Used Alone or Combined with Low-pH Treatment.}, journal = {International journal of molecular sciences}, volume = {25}, number = {13}, pages = {}, pmid = {39000327}, issn = {1422-0067}, support = {CA18113//EuromicropH COST action/ ; }, mesh = {*Biofilms/drug effects ; *Staphylococcus aureus/drug effects/physiology ; *Cymenes/pharmacology ; Hydrogen-Ion Concentration ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology ; Plankton/drug effects ; Capsules ; Drug Compounding/methods ; Drug Resistance, Bacterial/drug effects ; }, abstract = {Microbial biofilms pose severe problems in the medical field and food industry, as they are the cause of many serious infections and food-borne diseases. The extreme biofilms' resistance to conventional anti-microbial treatments presents a major challenge to their elimination. In this study, the difference in resistance between Staphylococcus aureus DSMZ 12463 biofilms, biofilm-detached cells, and planktonic cells against microcapsules containing carvacrol was assessed. The antimicrobial/antibiofilm activity of low pH disinfection medium containing the microencapsulated carvacrol was also studied. In addition, the effect of low pH on the in vitro carvacrol release from microcapsules was investigated. The minimum inhibitory concentration of microencapsulated carvacrol was 0.625 mg mL[-1]. The results showed that biofilms exhibited greater resistance to microencapsulated carvacrol than the biofilm-detached cells and planktonic cells. Low pH treatment alone, by hydrochloric acid addition, showed no bactericidal effect on any of the three states of S. aureus strain. However, microencapsulated carvacrol was able to significantly reduce the planktonic cells and biofilm-detached cells below the detection limit (no bacterial counts), and the biofilm by approximatively 3 log CFU mL[-1]. In addition, results showed that microencapsulated carvacrol combined with low pH treatment reduced biofilm by more than 5 log CFU mL[-1]. Thus, the use of microencapsulated carvacrol in acidic environment could be a promising approach to combat biofilms from abiotic surfaces.}, }
@article {pmid38998500, year = {2024}, author = {Wu, D and Hao, L and Liu, X and Li, X and Zhao, G}, title = {The Anti-Biofilm Properties of Phloretin and Its Analogs against Porphyromonas gingivalis and Its Complex Flora.}, journal = {Foods (Basel, Switzerland)}, volume = {13}, number = {13}, pages = {}, pmid = {38998500}, issn = {2304-8158}, support = {21978101//National Natural Science Foundation of China/ ; 22278159//National Natural Science Foundation of China/ ; }, abstract = {Porphyromonas gingivalis is crucial for the pathogenesis of periodontitis. This research investigated the effects of the fruit-derived flavonoid phloretin and its analogs on the growth of pure P. gingivalis and the flora of P. gingivalis mixed with the symbiotic oral pathogens Fusobacterium nucleatum and Streptococcus mitis. The results showed that the tested flavonoids had little effect on the biofilm amount of pure P. gingivalis, but significantly reduced the biofilm amount of mixed flora to 83.6~89.1%. Biofilm viability decreased to 86.7~92.8% in both the pure- and mixed-bacterial groups after naringenin and phloretin treatments. SEM showed that phloretin and phlorizin displayed a similar and remarkable destructive effect on P. gingivalis and the mixed biofilms. Transcriptome analysis confirmed that biofilm formation was inhibited by these flavonoids, and phloretin significantly regulated the transcription of quorum sensing. Phlorizin and phloretin reduced AI-2 activity to 45.9% and 55.4%, respectively, independent of the regulation of related gene transcription. This research marks the first finding that these flavonoids possess anti-biofilm properties against P. gingivalis and its intricate bacterial community, and the observed performance variations, driven by structural differences, underscore the existence of intriguing structure-activity relationships.}, }
@article {pmid38998429, year = {2024}, author = {Fernández-Grajera, M and Pacha-Olivenza, MA and Fernández-Calderón, MC and González-Martín, ML and Gallardo-Moreno, AM}, title = {Dynamic Adhesive Behavior and Biofilm Formation of Staphylococcus aureus on Polylactic Acid Surfaces in Diabetic Environments.}, journal = {Materials (Basel, Switzerland)}, volume = {17}, number = {13}, pages = {}, pmid = {38998429}, issn = {1996-1944}, support = {TED2021-131345B-I00//Ministerio de Ciencia, Innovaci&#xf3;n y Universidades/ ; TED2021-131345B-I00//Fondo Europeo de Desarrollo Regional/ ; PID2022-140422OB-I00//Ministerio de Ciencia, Innovaci&#xf3;n y Universidades/ ; PID2022-140422OB-I00//Fondo Europeo de Desarrollo Regional/ ; IB20092//Consejer&#xed;a de Educaci&#xf3;n y Empleo, Junta de Extremadura/ ; Action VI-03//Universidad de Extremadura/ ; }, abstract = {Interest in biodegradable implants has focused attention on the resorbable polymer polylactic acid. However, the risk of these materials promoting infection, especially in patients with existing pathologies, needs to be monitored. The enrichment of a bacterial adhesion medium with compounds that are associated with human pathologies can help in understanding how these components affect the development of infectious processes. Specifically, this work evaluates the influence of glucose and ketone bodies (in a diabetic context) on the adhesion dynamics of S. aureus to the biomaterial polylactic acid, employing different approaches and discussing the results based on the physical properties of the bacterial surface and its metabolic activity. The combination of ketoacidosis and hyperglycemia (GK2) appears to be the worst scenario: this system promotes a state of continuous bacterial colonization over time, suppressing the stationary phase of adhesion and strengthening the attachment of bacteria to the surface. In addition, these supplements cause a significant increase in the metabolic activity of the bacteria. Compared to non-enriched media, biofilm formation doubles under ketoacidosis conditions, while in the planktonic state, it is glucose that triggers metabolic activity, which is practically suppressed when only ketone components are present. Both information must be complementary to understand what can happen in a real system, where planktonic bacteria are the ones that initially colonize a surface, and, subsequently, these attached bacteria end up forming a biofilm. This information highlights the need for good monitoring of diabetic patients, especially if they use an implanted device made of PLA.}, }
@article {pmid38995023, year = {2024}, author = {Danhorn, T and Hentzer, M and Givskov, M and Parsek, MR and Fuqua, C}, title = {Erratum for Danhorn et al., "Phosphorus Limitation Enhances Biofilm Formation of the Plant Pathogen Agrobacterium tumefaciens through the PhoR-PhoB Regulatory System".}, journal = {Journal of bacteriology}, volume = {206}, number = {8}, pages = {e0023824}, doi = {10.1128/jb.00238-24}, pmid = {38995023}, issn = {1098-5530}, }
@article {pmid38992841, year = {2024}, author = {Yui, S and Karia, K and Ali, S}, title = {Evaluation of novel disinfection methods for the remediation of heavily contaminated thermostatic mixing valves and water systems with Pseudomonas aeruginosa biofilm: considerations for new and existing healthcare water systems.}, journal = {The Journal of hospital infection}, volume = {151}, number = {}, pages = {195-200}, doi = {10.1016/j.jhin.2024.05.024}, pmid = {38992841}, issn = {1532-2939}, mesh = {*Biofilms/growth &amp; development/drug effects ; *Pseudomonas aeruginosa/physiology/drug effects ; *Disinfection/methods ; *Peracetic Acid/pharmacology ; *Disinfectants/pharmacology ; Water Microbiology ; Humans ; }, abstract = {BACKGROUND: Pseudomonas aeruginosa is a leading cause of nosocomial Gram-negative bacteraemia. Water systems are a well-documented source of P. aeruginosa and established biofilms are difficult to remove.<br><br>AIM: To evaluate the efficacy of regular flushing, peracetic acid disinfection, in-tap thermal disinfection, and in-line thermal disinfection to eradicate P.&#xa0;aeruginosa biofilm in a colonized tap model.<br><br>METHODS: A simulated tap system was constructed and inoculated with a reference and an environmental strain of P.&#xa0;aeruginosa to form biofilm. Water samples were collected from the taps and P.&#xa0;aeruginosa levels enumerated following disinfection methods. To simulate regular flushing, taps were flushed for 5&#xa0;min, five times per day with water tested daily. Peracetic acid (4000&#xa0;ppm) was manually injected into the system and flushed through the system with a pump. Thermal flushing at 60&#xa0;&#xb0;C was performed in-line and with an in-tap bypass valve. Tests were conducted with cross-linked polyethylene (PEX) piping and repeated with copper piping.<br><br>FINDINGS: Regular flushing and peracetic acid applied with a pump did not reduce P.&#xa0;aeruginosa levels. A limited reduction was observed when manually injecting peracetic acid. In-tap thermal flushing eradicated P.&#xa0;aeruginosa in copper piping but not PEX. In-line thermal flushing was the most effective at reducing P.&#xa0;aeruginosa levels; however, it did not eradicate the biofilm.<br><br>CONCLUSION: In-line thermal flushing was the most effective method to remove P.&#xa0;aeruginosa biofilm. Results vary significantly with the strain of bacteria and the composition of the plumbing. Several methods used in combination may be necessary to remove established biofilm.}, }
@article {pmid38992475, year = {2024}, author = {Isolani, R and Pilatti, F and de Paula, MN and Valone, L and da Silva, EL and de Oliveira Caleare, A and Seixas, FAV and Hensel, A and Mello, JCP}, title = {Limonium brasiliense rhizomes extract against virulence factors of Porphyromonas gingivalis: Inhibition of gingipains, bacterial adhesion, and biofilm formation.}, journal = {Fitoterapia}, volume = {177}, number = {}, pages = {106120}, doi = {10.1016/j.fitote.2024.106120}, pmid = {38992475}, issn = {1873-6971}, mesh = {*Biofilms/drug effects ; *Porphyromonas gingivalis/drug effects ; *Gingipain Cysteine Endopeptidases ; Humans ; *Adhesins, Bacterial/drug effects ; *Bacterial Adhesion/drug effects ; *Plant Extracts/pharmacology/chemistry ; *Virulence Factors ; *Cysteine Endopeptidases ; *Plumbaginaceae/chemistry ; Plant Roots/chemistry ; Proanthocyanidins/pharmacology/isolation &amp; purification ; KB Cells ; Anti-Bacterial Agents/pharmacology/isolation &amp; purification/chemistry ; Phytochemicals/pharmacology/isolation &amp; purification ; }, abstract = {Periodontitis is clinically characterized by destruction of the tooth support system and tooth loss. Porphyromonas gingivalis (Pg) plays a dominant role in periodontitis. Fractions and isolated compounds from an acetone-water extract of the roots of Limonium brasiliense (Lb) were tested in vitro for their anti-adhesive capacity against Pg on human KB buccal cells, influence on gingipains, the main virulence factors of Pg, and biofilm formation. Fractions EAF and FLB7 (50 μg/mL) reduced the bacterial adhesion of Pg to KB cells significantly (63 resp. 70%). The proanthocyanidin samarangenin A inhibited the adhesion (72%, 30 μM), samarangenin B (71%, 20 μM), and the flavan-3-ol epigallocatechin-3-O-gallate (79%, 30 μM). Fraction AQF, representing hydrophilic compounds, reduced the proteolytic activity of Arginin-specific gingipain (IC50 12.78 μg/mL). Fractions EAF and FLB7, characterized by lipohilic constituents, inhibited Arg-gingipain (IC50 3 μg/mL). On Lysine-specific gingipain, AQF has an IC50 15.89, EAF 14.15, and FLB7 6 μg/mL. The reduced bacterial adhesion is due to a strong interaction of proanthocyanidins with gingipains. AQF, EAF, and FLB7 significantly inhibited biofilm formation: IC50 11.34 (AQF), 11.66 (EAF), and 12.09 μg/mL (FLB7). In silico analysis indicated, that the polyphenols act against specific targets of Pg, not affecting mammalian cells. Therefore, Lb might be effective for prevention of periodontal disease by influencing virulence factors of Pg.}, }
@article {pmid38991244, year = {2024}, author = {Heusser, A and Wackernagel, I and Reinmann, M and Udert, KM}, title = {Increasing urine nitrification performance with sequential membrane aerated biofilm reactors.}, journal = {Water research}, volume = {261}, number = {}, pages = {122019}, doi = {10.1016/j.watres.2024.122019}, pmid = {38991244}, issn = {1879-2448}, mesh = {*Bioreactors ; *Nitrification ; *Biofilms ; *Ammonia/metabolism ; Urine/chemistry ; Membranes, Artificial ; Waste Disposal, Fluid ; }, abstract = {This study aimed to investigate whether separating organics depletion from nitrification increases the overall performance of urine nitrification. Separate organics depletion was facilitated with membrane aerated biofilm reactors (MABRs). The high pH and ammonia concentration in stored urine inhibited nitrification in the first stage and therewith allowed the separation of organics depletion from nitrification. An organics removal of 70 % was achieved at organic loading rates in the influent of 3.7 gCOD d[-1] m[-2]. Organics depletion in a continuous flow stirred tank reactor (CSTR) for organics depletion led to ammonia stripping through diffused aeration of up to 13 %. Using an MABR, diffusion into the lumen amounted for 4 % ammonia loss only. In the MABR, headspace volume and therefore ammonia loss through the headspace was negligible. By aerating the downstream MABR for nitrification with the off-gas of the MABR for organics depletion, 96 % of the ammonia stripped in the first stage could be recovered in the second stage, so that the overall ammonia loss was negligibly low. Nitrification of the organics-depleted urine was studied in MABRs, CSTRs, and sequencing batch reactors in fed batch mode (FBRs), the latter two operated with suspended biomass. The experiments demonstrated that upstream organics depletion can double the nitrification rate. In a laboratory-scale MABR, nitrification rates were recorded of up to 830 mgNL[-1] d[-1] (3.1 gN m[-2] d[-1]) with ambient air and over 1500 mgNL[-1] d[-1] (6.7 gN m[-2] d[-1]) with oxygen-enriched air. Experiments with a laboratory-scale MABR showed that increasing operational parameters such as pH, recirculation flow, scouring frequency, and oxygen content increased the nitrification rate. The nitrification in the MABR was robust even at high pH setpoints of 6.9 and was robust against process failures arising from operational mistakes. The hydraulic retention time (HRT) required for nitrification was only 1 to 2 days. With the preceding organics depletion, the HRT for our system requires 2 to 3 days in total, whereas a combined activated sludge system requires 4 to 8 days. The N2O concentration in the off-gas increases with increasing nitrification rates; however, the N2O emission factor was 2.8 % on average and independent of nitrification rates. These results indicate that the MABR technology has a high potential for efficient and robust production of ammonium nitrate from source-separated urine.}, }
@article {pmid38991000, year = {2024}, author = {Arif, M and Asif, A and Nazeer, K and Sultan, S and Riaz, S}, title = {Coexistence of β-lactamase genes and biofilm forming potential among carbapenem-resistant Acinetobacter baumannii in Lahore, Pakistan.}, journal = {Journal of infection in developing countries}, volume = {18}, number = {6}, pages = {943-949}, doi = {10.3855/jidc.19119}, pmid = {38991000}, issn = {1972-2680}, mesh = {*Biofilms/growth &amp; development ; *beta-Lactamases/genetics ; Humans ; Pakistan ; *Acinetobacter baumannii/genetics/drug effects ; Male ; Cross-Sectional Studies ; Adult ; Middle Aged ; Female ; *Acinetobacter Infections/microbiology ; *Anti-Bacterial Agents/pharmacology ; *Carbapenems/pharmacology ; Microbial Sensitivity Tests ; Young Adult ; Bacterial Proteins/genetics ; Adolescent ; }, abstract = {INTRODUCTION: Our goal was to investigate the antimicrobial resistance due to beta-lactamase genes and virulent determinants (biofilm-forming ability) expressed by Acinetobacter collected from health settings in Pakistan. A cross-sectional study was conducted for the molecular characterization of carbapenemases and biofilm-producing strains of Acinetobacter spp.<br><br>METHODOLOGY: Two twenty-three imipenem-resistant Acinetobacter isolates were analyzed from 2020 to 2023.The combination disk test and modified hodge test were performed. Biofilm forming ability was determined by polystyrene tube assay. Multiplex polymerase chain reaction (PCR) for virulent and biofilm-forming genes, and 16S rRNA sequencing were performed.<br><br>RESULTS: 118 (52.9%) carbapenem-resistant Acinetobacter (CR-AB) were isolated from wounds and pus, 121 (54.2%) from males, and 92 (41.2%) from 26-50-years-olds. More than 80% of strains produced &#x3b2;-lactamases and carbapenemases. Based on the PCR amplification of the ITS gene, 174 (78.0%) CR-AB strains were identified from CR-Acinetobacter non-baumannii (ANB). Most CR-AB were strong and moderate biofilm producers. Genetic analysis revealed the blaOXA-23, blaTEM, blaCTX-M blaNDM-1 and blaVIM were prevalent in CR-AB with frequencies 91 (94.8%), 68 (70.8%), 19 (19.7%), 53 (55.2%), 2 (2.0%) respectively. Among virulence genes, OmpA was dominant in CR-AB isolates from wound (83, 86.4%), csuE 63 (80.7%) from non-wound specimens and significantly correlated with blaNDM and blaOXA genes. Phylogenetic analysis revealed three different clades for strains based on specimens.<br><br>CONCLUSIONS: CR-AB was highly prevalent in Pakistan and associated with wound infections. The genes, blaOXA-23, blaTEM, blaCTX-M, and blaNDM-1 were detected in CR-AB. Most CR-AB were strong biofilm producers with virulent genes OmpA and csuE.}, }
@article {pmid38990088, year = {2024}, author = {Leistikow, KR and May, DS and Suh, WS and Vargas Asensio, G and Schaenzer, AJ and Currie, CR and Hristova, KR}, title = {Bacillus subtilis-derived peptides disrupt quorum sensing and biofilm assembly in multidrug-resistant Staphylococcus aureus.}, journal = {mSystems}, volume = {9}, number = {8}, pages = {e0071224}, pmid = {38990088}, issn = {2379-5077}, support = {U19 AI142720/AI/NIAID NIH HHS/United States ; U19AI142720//HHS | NIH | NIH Office of the Director (OD)/ ; W9132T-22-2-0001, W9132T-23-2-0003//U.S. Department of Defense (DOD)/ ; }, mesh = {*Biofilms/drug effects ; *Quorum Sensing/drug effects ; *Bacillus subtilis/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; Humans ; Peptides/pharmacology ; Methicillin-Resistant Staphylococcus aureus/drug effects ; Drug Resistance, Multiple, Bacterial/drug effects ; Microbial Sensitivity Tests ; Bacterial Proteins/genetics/metabolism ; Staphylococcus aureus/drug effects/physiology ; }, abstract = {UNLABELLED: Multidrug-resistant Staphylococcus aureus is one of the most clinically important pathogens in the world, with infections leading to high rates of morbidity and mortality in both humans and animals. The ability of S. aureus to form biofilms protects cells from antibiotics and promotes the transfer of antibiotic resistance genes; therefore, new strategies aimed at inhibiting biofilm growth are urgently needed. Probiotic species, including Bacillus subtilis, are gaining interest as potential therapies against S. aureus for their ability to reduce S. aureus colonization and virulence. Here, we search for strains and microbially derived compounds with strong antibiofilm activity against multidrug-resistant S. aureus by isolating and screening Bacillus strains from a variety of agricultural environments. From a total of 1,123 environmental isolates, we identify a single strain B. subtilis 6D1, with a potent ability to inhibit biofilm growth, disassemble mature biofilm, and improve antibiotic sensitivity of S. aureus biofilms through an Agr quorum sensing interference mechanism. Biochemical and molecular networking analysis of an active organic fraction revealed multiple surfactin isoforms, and an uncharacterized peptide was driving this antibiofilm activity. Compared with commercial high-performance liquid chromatography grade surfactin obtained from B. subtilis, we show these B. subtilis 6D1 peptides are significantly better at inhibiting biofilm formation in all four S. aureus Agr backgrounds and preventing S. aureus-induced cytotoxicity when applied to HT29 human intestinal cells. Our study illustrates the potential of exploring microbial strain diversity to discover novel antibiofilm agents that may help combat multidrug-resistant S. aureus infections and enhance antibiotic efficacy in clinical and veterinary settings.<br><br>IMPORTANCE: The formation of biofilms by multidrug-resistant bacterial pathogens, such as Staphylococcus aureus, increases these microorganisms' virulence and decreases the efficacy of common antibiotic regimens. Probiotics possess a variety of strain-specific strategies to reduce biofilm formation in competing organisms; however, the mechanisms and compounds responsible for these phenomena often go uncharacterized. In this study, we identified a mixture of small probiotic-derived peptides capable of Agr quorum sensing interference as one of the mechanisms driving antibiofilm activity against S. aureus. This collection of peptides also improved antibiotic killing and protected human gut epithelial cells from S. aureus-induced toxicity by stimulating an adaptive cytokine response. We conclude that purposeful strain screening and selection efforts can be used to identify unique probiotic strains that possess specially desired mechanisms of action. This information can be used to further improve our understanding of the ways in which probiotic and probiotic-derived compounds can be applied to prevent bacterial infections or improve bacterial sensitivity to antibiotics in clinical and agricultural settings.}, }
@article {pmid38990043, year = {2024}, author = {Momeni, SS and Cao, X and Xie, B and Rainey, K and Childers, NK and Wu, H}, title = {Intraspecies interactions of Streptococcus mutans impact biofilm architecture and virulence determinants in childhood dental caries.}, journal = {mSphere}, volume = {9}, number = {7}, pages = {e0077823}, pmid = {38990043}, issn = {2379-5042}, support = {R00 DE029527/DE/NIDCR NIH HHS/United States ; R01 DE016684/DE/NIDCR NIH HHS/United States ; R01 DE017954/DE/NIDCR NIH HHS/United States ; R01DE022350, T90DE022736//HHS | NIH | National Institute of Dental and Craniofacial Research (NIDCR)/ ; DE029527//HHS | NIH | National Institute of Dental and Craniofacial Research (NIDCR)/ ; K99 DE029527/DE/NIDCR NIH HHS/United States ; R01 DE022350/DE/NIDCR NIH HHS/United States ; T90 DE022736/DE/NIDCR NIH HHS/United States ; R01DE016684//HHS | NIH | National Institute of Dental and Craniofacial Research (NIDCR)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Streptococcus mutans/genetics/physiology/pathogenicity ; *Dental Caries/microbiology ; Humans ; Animals ; Child, Preschool ; Drosophila/microbiology ; Virulence ; Microbial Interactions ; Genotype ; Female ; Male ; Child ; Hydrogen-Ion Concentration ; Virulence Factors/genetics ; Disease Models, Animal ; Microscopy, Confocal ; }, abstract = {Early childhood dental caries (ECC) is the most common chronic disease among children, especially among low socioeconomic populations. Streptococcus mutans is most frequently associated with initiation of ECC. Although many studies report children with multiple S. mutans strains (i.e., genotypes) have greater odds of developing ECC, studies investigating intraspecies interactions in dental caries are lacking. This study investigates the impact of intraspecies interactions on cariogenic and fitness traits of clinical S. mutans isolates using in vitro and in vivo approaches. Association analysis evaluated if presence of multiple S. mutans genotypes within the first year of colonization was associated with caries. Initially, clinical S. mutans isolates from 10 children were evaluated. S. mutans strains (G09 and G18, most prevalent) isolated from one child were used for subsequent analysis. Biofilm analysis was performed for single and mixed cultures to assess cariogenic traits, including biofilm biomass, intra-polysaccharide, pH, and glucan. Confocal laser scanning microscopy (CLSM) and time-lapse imaging were used to evaluate spatial and temporal biofilm dynamics, respectively. A Drosophila model was used to assess colonization in vivo. Results showed the mean biofilm pH was significantly lower in co-cultured biofilms versus monoculture. Doubling of S. mutans biofilms was observed by CLSM and in vivo colonization in Drosophila for co-cultured S. mutans. Individual strains occupied specific domains in co-culture and G09 contributed most to increased co-culture biofilm thickness and colonization in Drosophila. Biofilm formation and acid production displayed distinct signatures in time-lapsed experiments. This study illuminates that intraspecies interactions of S. mutans significantly impacts biofilm acidity, architecture, and colonization.IMPORTANCEThis study sheds light on the complex dynamics of a key contributor to early childhood dental caries (ECC) by exploring intraspecies interactions of different S. mutans strains and their impact on cariogenic traits. Utilizing clinical isolates from children with ECC, the research highlights significant differences in biofilm architecture and acid production in mixed versus single genotype cultures. The findings reveal that co-cultured S. mutans strains exhibit increased cell density and acidity, with individual strains occupying distinct domains. These insights, enhanced by use of time-lapsed confocal laser scanning microscopy and a Drosophila model, offer a deeper understanding of ECC pathogenesis and potential avenues for targeted interventions.}, }
@article {pmid38989494, year = {2024}, author = {Datla, VDD and Uppalapati, LV and Pilli, HPK and Mandava, J and Kantheti, S and Komireddy, SNK and Chandolu, V}, title = {Effect of ultrasonic and Er,Cr:YSGG laser-activated irrigation protocol on dual-species root canal biofilm removal: An in vitro study.}, journal = {Journal of conservative dentistry and endodontics}, volume = {27}, number = {6}, pages = {613-620}, pmid = {38989494}, issn = {2950-4708}, abstract = {AIM: The aim of the study was to investigate the disinfecting efficacy of a standardized irrigating solution activated by ultrasonics or laser irradiation on mature dual-species biofilms at different root levels in vitro.<br><br>MATERIALS AND METHODS: Conventional access cavity preparations were done on 160 single-rooted mandibular premolar teeth with single canals. Freshly extracted oral microbial strains of Staphylococcus aureus, Streptococcus mutans, Enterococcus faecalis, and Candida albicans after biochemical confirmation were used to generate two discrete dual-species microbial inoculums. The sterilized tooth samples were randomly segregated into two groups (n = 80) and inoculated with a mixed inoculum of S. aureus + E. faecalis strains (Group 1) and S. mutans + C. albicans strains (Group 2), respectively. Following the 21-day incubation period under aerobic conditions, the infected specimens in each group were divided into four subgroups (n = 20) and subjected to experimental treatment protocols. This included a positive control (no treatment of biofilms), syringe irrigation alone with TruNatomy needle, passive ultrasonically activated irrigation with 20# Irrisafe tip, and laser agitation of irrigant with Er,Cr:YSGG laser using RFT 2 laser tip. Root canals of experimental specimens (except the control samples) are instrumented with TruNatomy rotary file system using 1:1 mixture of 3% NaOCl and 18% etidronic acid as irrigants. The quantitative assessment of reduction in viable biofilm microbes after treatment was done using colony-forming unit counts and confocal laser scanning microscopy image analysis. The obtained data were analyzed statistically with a significant level set at 0.05.<br><br>RESULTS: Laser-assisted irrigation has shown a considerably higher mean percentage reduction of microbes compared to ultrasonic agitation and the syringe irrigation showed the least microbial reduction (P = 0.001). No significant difference was noted between the three root regions of ultrasonic and laser groups (P > 0.05), whereas in the syringe groups, apical portions showed higher microbial counts compared to cervical and mid-root regions (P = 0.001).<br><br>CONCLUSION: Erbium laser-assisted irrigation has performed superior to ultrasonic agitation against both the experimental dual-species biofilms, while the syringe irrigation showed the least microbial reduction specifically at apical root portions.}, }
@article {pmid38988529, year = {2024}, author = {Wang, D and Zeng, N and Li, C and Li, Z and Zhang, N and Li, B}, title = {Fungal biofilm formation and its regulatory mechanism.}, journal = {Heliyon}, volume = {10}, number = {12}, pages = {e32766}, pmid = {38988529}, issn = {2405-8440}, abstract = {Fungal biofilm is a microbial community composed of fungal cells and extracellular polymeric substances (EPS). In recent years, fungal biofilms have played an increasingly important role in many fields. However, there are few studies on fungal biofilms and their related applications and development are still far from enough. Therefore, this review summarizes the composition and function of EPS in fungal biofilms, and improves and refines the formation process of fungal biofilms according to the latest viewpoints. Moreover, based on the study of Saccharomyces cerevisiae and Candida albicans, this review summarizes the gene regulation network of fungal biofilm synthesis, which is crucial for systematically understanding the molecular mechanism of fungal biofilm formation. It is of great significance to further develop effective methods at the molecular level to control harmful biofilms or enhance and regulate the formation of beneficial biofilms. Finally, the quorum sensing factors and mixed biofilms formed by fungi in the current research of fungal biofilms are summarized. These results will help to deepen the understanding of the formation process and internal regulation mechanism of fungal biofilm, provide reference for the study of EPS composition and structure, formation, regulation, group behavior and mixed biofilm formation of other fungal biofilms, and provide strategies and theoretical basis for the control, development and utilization of fungal biofilms.}, }
@article {pmid38988475, year = {2024}, author = {Khadraoui, N and Essid, R and Damergi, B and Fares, N and Gharbi, D and Forero, AM and Rodríguez, J and Abid, G and Kerekes, EB and Limam, F and Jiménez, C and Tabbene, O}, title = {Myrtus communis leaf compounds as novel inhibitors of quorum sensing-regulated virulence factors and biofilm formation: In vitro and in silico investigations.}, journal = {Biofilm}, volume = {8}, number = {}, pages = {100205}, pmid = {38988475}, issn = {2590-2075}, abstract = {Antibiotic resistance of the Gram-negative bacterium Pseudomonas aeruginosa and its ability to form biofilm through the Quorum Sensing (QS) mechanism are important challenges in the control of infections caused by this pathogen. The extract of Myrtus communis (myrtle) showed strong anti-QS effect on C hromobacterium . violaceum 6267 by inhibiting 80 % of the production of violacein pigment at a sub-MIC concentration of 1/8 (31.25 μg/mL). In addition, the extract exhibited an inhibitory effect on virulence factors of P. aeruginosa PAO1 at half MIC (125 μg/mL), significantly reducing the formation of biofilms (72.02 %), the swarming activity (75 %), and the production of protease (61.83 %) and pyocyanin (97 %). The active fraction also downregulated the expression of selected regulatory genes involved in the biofilm formation and QS in the P. aeruginosa PAO1 strain. These genes included the autoinducer synthase genes (lasI and rhlI), the genes involved in the expression of their corresponding receptors (lasR and rhlR), and the pqsA genes. The analysis of the active fraction by HPLC/UV/MS and NMR allowed the identification of three phenolic compounds, 3,5-di-O-galloylquinic acid, myricetin 3-O-α-l-rhamnopyranoside (myricitrin), and myricetin 3-O-(2″-O-galloyl)-ß-d-galactopyranoside. In silico studies showed that 3,5-di-O-galloylquinic acid, with an affinity score of -9.20 kcal/mol, had the highest affinity to the active site of the CviR protein (3QP8), a QS receptor from C. violaceum. Additionally, myricetin 3-O-α-l-rhamnopyranoside (myricitrin) and myricetin 3-O-(2″-O-galloyl)-ß-d-galactopyranoside interact to a lesser extent with 3QP8. In conclusion, this study contributed significantly to the discovery of new QS inhibitors from M. communis leaves against resistant Gram-negative pathogens.}, }
@article {pmid38988413, year = {2024}, author = {Dietl, S and Merkl, P and Sotiriou, GA}, title = {Prevention of uropathogenic E. coli biofilm formation by hydrophobic nanoparticle coatings on polymeric substrates.}, journal = {RSC applied interfaces}, volume = {1}, number = {4}, pages = {667-670}, pmid = {38988413}, issn = {2755-3701}, abstract = {Biofilms in infections are a major health-care challenge and strategies to reduce their formation on medical devices are crucial. Fabrication of superhydrophobic coatings based on hydrocarbon adsorption on rare-earth oxides constitutes an attractive strategy, but their capacity to prevent biofilm formation has not been studied. Here, we explore a scalable and reproducible nanofabrication process for the manufacture of such superhydrophobic coatings and study their antibiofilm activity against clinically-relevant uropathogenic E. coli. These coatings reduce bacterial biofilm formation and prevent biofouling with potential applications preventing medical device related infections.}, }
@article {pmid38986879, year = {2024}, author = {Han, NN and Yang, JH and Fan, NS and Jin, RC}, title = {Mechanistic insight into microbial interaction and metabolic pattern of anammox consortia on surface-modified biofilm carrier with extracellular polymeric substances.}, journal = {Bioresource technology}, volume = {407}, number = {}, pages = {131092}, doi = {10.1016/j.biortech.2024.131092}, pmid = {38986879}, issn = {1873-2976}, mesh = {*Biofilms ; *Extracellular Polymeric Substance Matrix/metabolism ; *Oxidation-Reduction ; Ammonia/metabolism ; Polypropylenes ; Nitrogen/metabolism ; Microbial Consortia/physiology ; Bacteria/metabolism ; Anaerobiosis/physiology ; Biomass ; Escherichia coli/metabolism ; }, abstract = {The extremely slow growth rate of anaerobic ammonia oxidation (anammox) bacteria limits full-scale application of anammox process worldwide. In this study, extracellular polymeric substances (EPS)-coated polypropylene (PP) carriers were prepared for biofilm formation. The biomass adhesion rate of EPS-PP carrier was 12 times that of PP carrier, and EPS-PP achieved significant enrichment of E. coli BY63. The 120-day continuous flow experiment showed that the EPS-PP carrier accelerated the formation of anammox biofilm, and the nitrogen removal efficiency increased by 10.5 %. In addition, the abundance of Candidatus Kuenenia in EPS-PP biofilm was 27.1%. Simultaneously, amino acids with high synthesis cost and the metabolites of glycerophospholipids related to biofilm formation on EPS-PP biofilm were significantly up-regulated. Therefore, EPS-PP carriers facilitated the rapid formation of anammox biofilm and promoted the metabolic activity of functional bacteria, which further contributed to the environmental and economic sustainability of anammox process.}, }
@article {pmid38986504, year = {2024}, author = {Martin, JD and Tisler, S and Scheel, M and Svendsen, S and Anwar, MZ and Zervas, A and Ekelund, F and Bester, K and Hansen, LH and Jacobsen, CS and Ellegaard-Jensen, L}, title = {Total RNA analysis of the active microbiome on moving bed biofilm reactor carriers under incrementally increasing micropollutant concentrations.}, journal = {FEMS microbiology ecology}, volume = {100}, number = {9}, pages = {}, pmid = {38986504}, issn = {1574-6941}, support = {AUFF-E-2017-7-21//Aarhus University Research Foundation/ ; /CAPMC/CIHR/Canada ; //Michael Smith Health Research BC/ ; }, mesh = {*Biofilms/growth &amp; development ; *Microbiota ; *Bioreactors/microbiology ; *Wastewater/microbiology ; Water Pollutants, Chemical/metabolism ; Bacteria/genetics/metabolism/classification/growth &amp; development/drug effects ; Biodegradation, Environmental ; Waste Disposal, Fluid/methods ; }, abstract = {Micropollutants are increasingly prevalent in the aquatic environment. A major part of these originates from wastewater treatment plants since traditional treatment technologies do not remove micropollutants sufficiently. Moving bed biofilm reactors (MBBRs), however, have been shown to aid in micropollutant removal when applied to conventional wastewater treatment as a polishing step. Here, we used Total RNA sequencing to investigate both the active microbial community and functional dynamics of MBBR biofilms when these were exposed to increasing micropollutant concentrations over time. Concurrently, we conducted batch culture experiments using biofilm carriers from the MBBRs to assess micropollutant degradation potential. Our study showed that biofilm eukaryotes, in particular protozoa, were negatively influenced by micropollutant exposure, in contrast to prokaryotes that increased in relative abundance. Further, we found several functional genes that were differentially expressed between the MBBR with added micropollutants and the control. These include genes involved in aromatic and xenobiotic compound degradation. Moreover, the biofilm carrier batch experiment showed vastly different alterations in benzotriazole and diclofenac degradation following the increased micropollutant concentrations in the MBBR. Ultimately, this study provides essential insights into the microbial community and functional dynamics of MBBRs and how an increased load of micropollutants influences these dynamics.}, }
@article {pmid38984682, year = {2024}, author = {Fruleux, T and Sauleau, P and Caudal, F and Champion, M and Chauvin, L and Castro, M and Le Duigou, A}, title = {Marine biofilm formation on flax fibre reinforced biocomposites.}, journal = {Biofouling}, volume = {40}, number = {7}, pages = {415-430}, doi = {10.1080/08927014.2024.2373870}, pmid = {38984682}, issn = {1029-2454}, mesh = {*Biofilms/growth &amp; development ; *Flax/microbiology/chemistry ; *Pseudoalteromonas/physiology ; Bacterial Adhesion ; }, abstract = {Artificial reefs represent useful tools to revitalize coastal and ocean ecosystems. Their formulation determines the biofilm formation which is the prerequisite for the colonization process by marine micro- and macroorganisms. In comparison with concrete, biobased polymers offer improved characteristics, including architecture, formulation, rugosity and recycling. This article aims to explore a new scale of artificial reef made of biocomposites reinforced with a high flax fibre (Linum utilatissimum) content (30%). Cellular adhesion and resulting biofilm formation were assessed using two marine microorganisms: Pseudoalteromonas sp. 3J6 and Cylindrotheca closterium. The influence of flax fibre leachates and plastic monomers on the growth of those marine microorganisms were also evaluated. Results indicated that the introduction of flax fibres inside the polymer matrix modified its physicochemical properties thus modulating adhesion and biofilm formation depending on the microorganism. This study gives insights for further developments of novel functionalized artificial reefs made of biocomposites.}, }
@article {pmid38982956, year = {2024}, author = {Ramaiah, KB and Suresh, I and Srinandan, CS and Sai Subramanian, N and Rayappan, JBB}, title = {A dual-sensing strategy for the early diagnosis of urinary tract infections via detecting biofilm cellulose using aromatic amino acid-capped Au and Ag nanoparticles.}, journal = {Journal of materials chemistry. B}, volume = {12}, number = {31}, pages = {7564-7576}, doi = {10.1039/d4tb00902a}, pmid = {38982956}, issn = {2050-7518}, mesh = {*Urinary Tract Infections/diagnosis/microbiology ; *Metal Nanoparticles/chemistry ; *Silver/chemistry ; *Gold/chemistry ; *Cellulose/chemistry ; *Biofilms ; Humans ; Colorimetry/methods ; Early Diagnosis ; Amino Acids, Aromatic/chemistry ; Electrochemical Techniques ; Molecular Docking Simulation ; }, abstract = {Currently, urinary tract infection (UTI) diagnosis focuses on planktonic cell detection rather than biofilm detection, but the facile identification of UPEC bacterial biofilms is crucial in UTI diagnosis as the biofilm formed by bacteria is the causative agent of recurrent and chronic UTIs. Therefore, in this work, we developed a simple, cost-effective, colorimetric, and electrochemical-based strategy for the detection of cellulose in urine. Cellulose, a biofilm matrix component, was detected using tyrosine-capped gold and silver nanoparticles through a visible colorimetric change with a decrease in the absorbance intensity and a decrease in current response in the case of cyclic voltammetry. The sensor displayed a linear detection range of 10-70 mg mL[-1] for colorimetry and 10-300 μg mL[-1] for cyclic voltammetry with a good selectivity of <2.8% and a recovery rate of 95-100% in real-time sample analysis. Moreover, the binding affinity of cellulose with tyrosine was investigated using molecular docking studies to validate the sensing mechanism. We anticipate that our work will aid clinicians in the implementation of rapid, cost-effective, and definitive diagnosis of UTIs.}, }
@article {pmid38980701, year = {2024}, author = {Yazdani-Ahmadabadi, H and Yu, K and Gonzalez, K and Luo, HD and Lange, D and Kizhakkedathu, JN}, title = {Long-Term Prevention of Biofilm Formation by Polycatechol-Based Supramolecular Assemblies with Low Molecular Weight Polymers on Surfaces.}, journal = {ACS applied materials &amp; interfaces}, volume = {16}, number = {29}, pages = {38631-38644}, pmid = {38980701}, issn = {1944-8252}, mesh = {*Biofilms/drug effects ; *Catechols/chemistry/pharmacology ; *Polymers/chemistry/pharmacology ; *Staphylococcus aureus/drug effects/physiology ; Molecular Weight ; Surface Properties ; Anti-Bacterial Agents/pharmacology/chemistry ; Coated Materials, Biocompatible/chemistry/pharmacology ; }, abstract = {Achievement of a stable surface coating with long-term resistance to biofilm formation remains a challenge. Catechol-based polymerization chemistry and surface deposition are used as tools for surface modification of diverse materials. However, the control of surface deposition of the coating, surface coverage, coating properties, and long-term protection against biofilm formation remain to be solved. We report a new approach based on supramolecular assembly to generate long-acting antibiofilm coating. Here, we utilized catechol chemistry in combination with low molecular weight amphiphilic polymers for the generation of such coatings. Screening studies with diverse low molecular weight (LMW) polymers and different catechols are utilized to identify lead compositions, which resulted in a thick coating with high surface coverage, smoothness, and antibiofilm activity. We have identified that small supramolecular assemblies (∼10 nm) formed from a combination of polydopamine and LMW poly(N-vinyl caprolactam) (PVCL) resulted in relatively thick coating (∼300 nm) with excellent surface coverage in comparison to other polymers and catechol combinations. The coating properties, such as thickness (10-300 nm) and surface hydrophilicity (with water contact angle: 20-60°), are readily controlled. The optimal coating composition showed excellent antibiofilm properties with long-term (>28 days) antibiofilm activity against both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) strains. We further utilized the combination of optimal binary coating with silver to generate a coating with sustained release of silver ions, resulting in killing both adhered and planktonic bacteria and preventing long-term surface bacterial colonization. The new coating method utilizing LMW polymers opens a new avenue for the development of a novel class of thick, long-acting antibiofilm coatings.}, }
@article {pmid38979200, year = {2024}, author = {Korshoj, LE and Kielian, T}, title = {Bacterial single-cell RNA sequencing captures biofilm transcriptional heterogeneity and differential responses to immune pressure.}, journal = {bioRxiv : the preprint server for biology}, volume = {}, number = {}, pages = {}, doi = {10.1101/2024.06.28.601229}, pmid = {38979200}, issn = {2692-8205}, abstract = {Biofilm formation is an important mechanism of survival and persistence for many bacterial pathogens. These multicellular communities contain subpopulations of cells that display vast metabolic and transcriptional diversity along with high recalcitrance to antibiotics and host immune defenses. Investigating the complex heterogeneity within biofilm has been hindered by the lack of a sensitive and high-throughput method to assess stochastic transcriptional activity and regulation between bacterial subpopulations, which requires single-cell resolution. We have developed an optimized bacterial single-cell RNA sequencing method, BaSSSh-seq, to study Staphylococcus aureus diversity during biofilm growth and transcriptional adaptations following immune cell exposure. We validated the ability of BaSSSh-seq to capture extensive transcriptional heterogeneity during biofilm compared to planktonic growth. Application of new computational tools revealed transcriptional regulatory networks across the heterogeneous biofilm subpopulations and identification of gene sets that were associated with a trajectory from planktonic to biofilm growth. BaSSSh-seq also detected alterations in biofilm metabolism, stress response, and virulence that were tailored to distinct immune cell populations. This work provides an innovative platform to explore biofilm dynamics at single-cell resolution, unlocking the potential for identifying biofilm adaptations to environmental signals and immune pressure.}, }
@article {pmid38977975, year = {2024}, author = {Alabdullatif, M}, title = {Evaluating the effects of temperature and agitation on biofilm formation of bacterial pathogens isolated from raw cow milk.}, journal = {BMC microbiology}, volume = {24}, number = {1}, pages = {251}, pmid = {38977975}, issn = {1471-2180}, mesh = {Animals ; *Biofilms/growth &amp; development ; *Milk/microbiology ; *Temperature ; Cattle ; *Bacteria/isolation &amp; purification/classification/growth &amp; development ; Saudi Arabia ; Food Microbiology ; Bacterial Physiological Phenomena ; }, abstract = {OBJECTIVES: To study the effect of agitation and temperature on biofilm formation (cell aggregates embedded within a self-produced matrix) by pathogenic bacteria isolated from Raw cow milk (RCM).<br><br>METHODS: A 40 RCM samples were gathered from eight dairy farms in Riyadh, Saudi Arabia. After bacterial culturing and isolation, gram staining was performed, and all pathogenic, identified using standard criteria established by Food Standards Australia New Zealand (FSANZ), and non-pathogenic bacteria were identified using VITEK-2 and biochemical assays. To evaluate the effects of temperature and agitation on biofilm formation, isolated pathogenic bacteria were incubated for 24&#xa0;h under the following conditions: 4&#xa0;&#xb0;C with no agitation (0&#xa0;rpm), 15&#xa0;&#xb0;C with no agitation, 30&#xa0;&#xb0;C with no agitation, 30&#xa0;&#xb0;C with 60&#xa0;rpm agitation, and 30&#xa0;&#xb0;C with 120&#xa0;rpm agitation. Then, biofilms were measured using a crystal violet assay.<br><br>RESULTS: Of the eight farm sites, three exhibited non-pathogenic bacterial contamination in their raw milk samples. Of the total of 40 raw milk samples, 15/40 (37.5%; from five farms) were contaminated with pathogenic bacteria. Overall, 346 bacteria were isolated from the 40 samples, with 329/346 (95.1%) considered as non-pathogenic and 17/346 (4.9%) as pathogenic. Most of the isolated pathogenic bacteria exhibited a significant (p&#x2009;<&#x2009;0.01) increase in biofilm formation when grown at 30&#xa0;&#xb0;C compared to 4&#xa0;&#xb0;C and when grown with 120&#xa0;rpm agitation compared to 0&#xa0;rpm.<br><br>CONCLUSION: Herein, we highlight the practices of consumers in terms of transporting and storing (temperature and agitation) can significantly impact on the growth of pathogens and biofilm formation in RCM.}, }
@article {pmid38977038, year = {2024}, author = {Kumar Jaiswal, V and Dutta Gupta, A and Sonwani, RK and Shekher Giri, B and Sharan Singh, R}, title = {Enhanced biodegradation of 2, 4-dichlorophenol in packed bed biofilm reactor by impregnation of polyurethane foam with Fe3O4 nanoparticles: Bio-kinetics, process optimization, performance evaluation and toxicity assessment.}, journal = {Bioresource technology}, volume = {406}, number = {}, pages = {131085}, doi = {10.1016/j.biortech.2024.131085}, pmid = {38977038}, issn = {1873-2976}, mesh = {*Chlorophenols ; *Polyurethanes/chemistry ; *Biofilms/drug effects ; *Biodegradation, Environmental ; Kinetics ; *Bioreactors ; Water Pollutants, Chemical ; Animals ; }, abstract = {In this work, an effort has been made to enhance the efficacy of biological process for the effective degradation of 2, 4-dichlorophenol (2, 4-DCP) from wastewater. The polyurethane foam was modified with Fe3O4 nanoparticles and combined with polyvinyl alcohol, sodium alginate, and bacterial consortium for biodegradation of 2, 4-DCP in a packed bed biofilm reactor. The maximum removal efficiency of 2, 4-DCP chemical oxygen demand, and total organic carbon were found to be 92.51 ± 0.83 %, 86.85 ± 1.32, and 91.78 ± 1.24 %, respectively, in 4 days and 100 mg L[-1] of 2, 4-DCP concentration at an influent loading rate of 2 mg L[-1]h[-1] and hydraulic retention time of 50 h. Packed bed biofilm reactor was effective for up to four cycles to remove 2, 4-DCP. Growth inhibition kinetics were evaluated using the Edward model, yielding maximum growth rate of 0.45 day[-1], inhibition constant of 110.6 mg L[-1], and saturation constant of 62.3 mg L[-1].}, }
@article {pmid38975180, year = {2024}, author = {Jonblat, S and As-Sadi, F and El Khoury, A and Badr, N and Kallassy, M and Chokr, A}, title = {Determining the dispersion time in Staphylococcus epidermidis biofilm using physical and molecular approaches.}, journal = {Heliyon}, volume = {10}, number = {12}, pages = {e32389}, pmid = {38975180}, issn = {2405-8440}, abstract = {Despite being an innocuous commensal of human skin and mucous membranes, Staphylococcus epidermidis, infects surgical wounds and causes infections through biofilm formation. This study evaluates, in a time-dependent experiment, the self-dispersion of S. epidermidis CIP 444 biofilm when formed on borosilicate glass (hydrophilic) and polystyrene (hydrophobic) surfaces, using physical and molecular approaches. During a seven-day period of incubation, absorbance measurement revealed a drop in biofilm optical density on both studied surfaces on day 4 (0.043-0.035 nm/cm[2], polystyrene), (0.06-0.053 nm/cm[2], borosilicate glass). Absorbance results were correlated with crystal violet staining that showed a clear detachment from day 4. The blue color increases again on day 7, with an increase in biofilm optical density indicating the regeneration of the biofilm. Changes in gene expression in the S. epidermidis biofilm were assessed using a real-time reverse transcription-polymerase chain reaction. High expression of agr genes was detected on days 4 and 5, confirming our supposition of dispersion in this period, autolysin genes like atlE1 and aae were upregulated from day 3 until day 6 and the genes responsible for slime production and biofilm accumulation, were upregulated on days 4, 5, and 6 (ica ADBC) and on days 5, 6 and 7 (aap), indicating a dual process taking place. These findings suggest that S. epidermidis CIP 444 biofilms disperse at day 4 and reform at day 7. Over the course of the seven-day investigation, 2[-ΔΔCt] results showed that some genes in the biofilm were dramatically enhanced while others were significantly decreased as compared to planktonic ones.}, }
@article {pmid38974467, year = {2024}, author = {Myers, C and Atkins, GR and Villarreal, J and Sutton, RB and Cornwall, GA}, title = {The mouse epididymal amyloid matrix is a mammalian counterpart of a bacterial biofilm.}, journal = {iScience}, volume = {27}, number = {6}, pages = {110152}, pmid = {38974467}, issn = {2589-0042}, abstract = {The mouse epididymis is a long tubule connecting the testis to the vas deferens. Its primary functions are to mature spermatozoa into motile and fertile cells and to protect them from pathogens that ascend the male tract. We previously demonstrated that a functional extracellular amyloid matrix surrounds spermatozoa in the epididymal lumen and has host defense functions, properties not unlike that of an extracellular biofilm that encloses and protects a bacterial community. Here we show the epididymal amyloid matrix also structurally resembles a biofilm by containing eDNA, eRNA, and mucin-like polysaccharides. Further these structural components exhibit comparable behaviors and perform functions such as their counterparts in bacterial biofilms. Our studies suggest that nature has used the ancient building blocks of bacterial biofilms to form an analogous structure that nurtures and protects the mammalian male germline.}, }
@article {pmid38974376, year = {2024}, author = {Hu, Z and Yin, X and Fan, G and Liao, X}, title = {Global Trends in Orthopedic Biofilm Research: A Bibliometric Analysis of 1994-2022.}, journal = {Journal of multidisciplinary healthcare}, volume = {17}, number = {}, pages = {3057-3069}, pmid = {38974376}, issn = {1178-2390}, abstract = {OBJECTIVE: Bibliometric analysis is commonly used to visualize the knowledge foundation, trends, and patterns in a specific scientific field by performing a quantitative evaluation of the relevant literature. The purpose of this study was to perform a bibliometric analysis of recent studies in the field of orthopedic biofilm research and identify its current trends and hotspots.<br><br>METHODS: Research studies were retrieved from the Web of Science Core Collection and Scopus databases and analyzed in bibliometrix with R package (4.2.2).<br><br>RESULTS: A total of 2426 literature were included in the study. Journal of orthopaedic research and Clinical orthopaedics and related research ranked first in terms of productivity and impact, with 57 published articles and 32 h-index, respectively. Trampuz A, Ohio State Univ and the United States ranked as the most productive authors, institutions, and countries. Biofilm formation, role of sonication, biomaterial mechanism and antibiotic loading have been investigated as the trend and hotspots in the field of orthopedic biofilm research.<br><br>CONCLUSION: This study provides a thorough overview of the state of the art of current orthopedic biofilm research and offers valuable insights into recent trends and hotspots in this field.}, }
@article {pmid38973924, year = {2024}, author = {Sedighi, O and Bednarke, B and Sherriff, H and Doiron, AL}, title = {Nanoparticle-Based Strategies for Managing Biofilm Infections in Wounds: A Comprehensive Review.}, journal = {ACS omega}, volume = {9}, number = {26}, pages = {27853-27871}, pmid = {38973924}, issn = {2470-1343}, abstract = {Chronic wounds containing opportunistic bacterial pathogens are a growing problem, as they are the primary cause of morbidity and mortality in developing and developed nations. Bacteria can adhere to almost every surface, forming architecturally complex communities called biofilms that are tolerant to an individual's immune response and traditional treatments. Wound dressings are a primary source and potential treatment avenue for biofilm infections, and research has recently focused on using nanoparticles with antimicrobial activity for infection control. This Review categorizes nanoparticle-based approaches into four main types, each leveraging unique mechanisms against biofilms. Metallic nanoparticles, such as silver and copper, show promising data due to their ability to disrupt bacterial cell membranes and induce oxidative stress, although their effectiveness can vary based on particle size and composition. Phototherapy-based nanoparticles, utilizing either photodynamic or photothermal therapy, offer targeted microbial destruction by generating reactive oxygen species or localized heat, respectively. However, their efficacy depends on the presence of light and oxygen, potentially limiting their use in deeper or more shielded biofilms. Nanoparticles designed to disrupt extracellular polymeric substances directly target the biofilm structure, enhancing the penetration and efficacy of antimicrobial agents. Lastly, nanoparticles that induce biofilm dispersion represent a novel strategy, aiming to weaken the biofilm's defense and restore susceptibility to antimicrobials. While each method has its advantages, the selection of an appropriate nanoparticle-based treatment depends on the specific requirements of the wound environment and the type of biofilm involved. The integration of these nanoparticles into wound dressings not only promises enhanced treatment outcomes but also offers a reduction in the overall use of antibiotics, aligning with the urgent need for innovative solutions in the fight against antibiotic-tolerant infections. The overarching objective of employing these diverse nanoparticle strategies is to replace antibiotics or substantially reduce their required dosages, providing promising avenues for biofilm infection management.}, }
@article {pmid38973863, year = {2024}, author = {Wong, MY and Lin, BS and Hu, PS and Huang, TY and Huang, YK}, title = {Nanoparticles of Cs0.33WO3 as Antibiofilm Agents and Photothermal Treatment to Inhibit Biofilm Formation.}, journal = {ACS omega}, volume = {9}, number = {26}, pages = {28144-28154}, pmid = {38973863}, issn = {2470-1343}, abstract = {Metal oxide nanoparticles with photothermal properties have attracted considerable research attention for their use in biomedical applications. Cesium tungsten oxide (Cs0.33WO3) nanoparticles (NPs) exhibit strong absorption in the NIR region due to localized surface plasmon resonance, through which they convert light to heat; hence, they can be applied to photothermal treatment for bacteria and biofilm ablation. Herein, Cs0.33WO3 NPs were synthesized through solid-phase synthesis, and their physical properties were characterized through Zetasizer, energy dispersive X-ray spectroscopy, Fourier transform infrared spectrometer, and scanning and transmission electron microscopy (SEM and TEM, respectively). Burkholderia cenocepacia isolates were cultured in tryptic soy broth supplemented with glucose, and the biofilm inhibition and antibiofilm effects of the NPs were determined using a crystal violet assay and the Cell Counting Kit-8 (CCK-8) assay. The biofilm morphology and viability of NP-treated cultures after NIR irradiation were evaluated through SEM and confocal microscopy, respectively. The cytotoxicity of NPs to human macrophages was also assessed using the CCK-8 assay. The NPs effectively inhibited biofilm formation, with a formation rate of <10% and a viability rate of <50% at the concentration of ≥200 μg/mL. The confocal analysis revealed that NIR irradiation markedly enhanced biofilm cytotoxicity after treatment with the NPs. The assay of cytotoxicity to human macrophages demonstrated the biocompatibility of the NPs and NIR irradiation. In sum, the Cs0.33WO3 NPs displayed effective biofilm inhibition and antibiofilm activity at 200 μg/mL treatment concentration; they exhibited an enhancement effect under the NIR irradiation, suggesting Cs0.33WO3 NPs are a potential candidate agent for NIR-irradiated photothermal treatment in bacterial biofilm inhibition and antibiofilm.}, }
@article {pmid38973737, year = {2024}, author = {Ji, Y and Hao, J and Tao, X and Li, Z and Chen, L and Qu, N}, title = {Preparation and anti-tumor activity of paclitaxel silk protein nanoparticles encapsulated by biofilm.}, journal = {Pharmaceutical development and technology}, volume = {29}, number = {6}, pages = {627-638}, doi = {10.1080/10837450.2024.2376075}, pmid = {38973737}, issn = {1097-9867}, mesh = {*Paclitaxel/administration &amp; dosage/pharmacokinetics/pharmacology ; *Nanoparticles/chemistry ; Animals ; Humans ; *Antineoplastic Agents, Phytogenic/administration &amp; dosage/pharmacokinetics/pharmacology ; *Biofilms/drug effects ; *Silk/chemistry ; Cell Line, Tumor ; Mice ; Drug Carriers/chemistry ; Escherichia coli/drug effects ; Biological Availability ; Male ; Rats ; Mice, Inbred BALB C ; }, abstract = {In order to overcome the poor bioavailability of paclitaxel (PTX), in this study, self-assembled paclitaxel silk fibronectin nanoparticles (PTX-SF-NPs) were encapsulated with outer membrane vesicles of Escherichia coli (E. coil), and biofilm-encapsulated paclitaxel silk fibronectin nanoparticles (OMV-PTX-SF-NPs) were prepared by high-pressure co-extrusion, the size and zeta potential of the OMV-PTX-SF-NPs were measured. The antitumor effects of OMV-PTX-SF-NPs were evaluated by cellular and pharmacodynamic assays, and pharmacokinetic experiments were performed. The results showed that hydrophobic forces and hydrogen bonding played a major role in the interaction between paclitaxel and filipin proteins, and the size of OMV-PTX-SF-NPs was 199.8 ± 2.8 nm, zeta potential was -17.8 ± 1.3 mv. The cellular and in vivo pharmacokinetic assays demonstrated that the OMV-PTX-SF-NPs possessed a promising antitumor effect. Pharmacokinetic experiments showed that the AUC0-∞ of OMV-PTX-SF-NPs was 5.314 ± 0.77, which was much larger than that of free PTX, which was 0.744 ± 0.14. Overall, we have successfully constructed a stable oral formulation of paclitaxel with a sustained-release effect, which is able to effectively increase the bioavailability of paclitaxel, improve the antitumor activity, and reduce the adverse effects.}, }
@article {pmid38972505, year = {2024}, author = {Ohara, K and Tomiyama, K and Okuda, T and Tsutsumi, K and Ishihara, C and Hashimoto, D and Fujii, Y and Chikazawa, T and Kurita, K and Mukai, Y}, title = {Dipotassium glycyrrhizate prevents oral dysbiosis caused by Porphyromonas gingivalis in an in vitro saliva-derived polymicrobial biofilm model.}, journal = {Journal of oral biosciences}, volume = {66}, number = {3}, pages = {575-581}, doi = {10.1016/j.job.2024.07.001}, pmid = {38972505}, issn = {1880-3865}, mesh = {*Biofilms/drug effects ; *Dysbiosis/microbiology ; *Saliva/microbiology ; *Porphyromonas gingivalis/drug effects/pathogenicity ; *Glycyrrhizic Acid/pharmacology ; Humans ; In Vitro Techniques ; Microbiota/drug effects ; Glycyrrhiza/chemistry ; Periodontal Diseases/microbiology/prevention &amp; control ; RNA, Ribosomal, 16S/genetics ; }, abstract = {OBJECTIVES: Oral microbiome dysbiosis prevention is important to avoid the onset and progression of periodontal disease. Dipotassium glycyrrhizate (GK2) is a licorice root extract with anti-inflammatory effects, and its associated mechanisms have been well-reported. However, their effects on the oral microbiome have not been investigated. This study aimed to elucidate the effects of GK2 on the oral microbiome using an in vitro polymicrobial biofilm model.<br><br>METHODS: An in vitro saliva-derived polymicrobial biofilm model was used to evaluate the effects of GK2 on the oral microbiome. One-week anaerobic culture was performed, in which GK2 was added to the medium. Subsequently, microbiome analysis was performed based on the V1-V2 region of the 16&#xa0;S rRNA gene, and pathogenicity indices were assessed. We investigated the effects of GK2 on various bacterial monocultures by evaluating its inhibitory effects on cell growth, based on culture turbidity.<br><br>RESULTS: GK2 treatment altered the microbiome structure and decreased the relative abundance of periodontal pathogenic bacteria, including Porphyromonas. Moreover, GK2 treatment reduced the DPP4 activity -a pathogenicity index of periodontal disease. Specifically, GK2 exhibited selective antibacterial activity against periodontal pathogenic bacteria.<br><br>CONCLUSIONS: These findings suggest that GK2 has a selective antibacterial effect against periodontal pathogenic bacteria; thus, preventing oral microbiome dysbiosis. Therefore, GK2 is expected to contribute to periodontal disease prevention by modulating the oral microbiome toward a state with low inflammatory potential, thereby utilizing its anti-inflammatory properties on the host.}, }
@article {pmid38972366, year = {2024}, author = {Chaves, AC and Boa Ventura, PV and Pereira, MS and da Silva, BF and de Carvalho, FJN and Costa, RA and Lima, BP and Maciel, WC and Carneiro, VA}, title = {Preliminary snapshot reveals a relationship between multidrug-resistance and biofilm production among enterobacteriaceae isolated from fecal samples of farm-raised poultry in ceará, Brazil.}, journal = {Microbial pathogenesis}, volume = {193}, number = {}, pages = {106778}, doi = {10.1016/j.micpath.2024.106778}, pmid = {38972366}, issn = {1096-1208}, mesh = {Animals ; *Biofilms/growth &amp; development/drug effects ; Brazil ; *Drug Resistance, Multiple, Bacterial ; *beta-Lactamases/genetics/metabolism ; *Feces/microbiology ; *Enterobacteriaceae/drug effects/isolation &amp; purification/genetics ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology ; *Chickens/microbiology ; *Farms ; Bacterial Proteins/genetics/metabolism ; Poultry/microbiology ; Enterobacteriaceae Infections/microbiology/veterinary ; }, abstract = {Antimicrobial resistance and biofilm formation by microbial pathogens pose a significant challenge to poultry production systems due to the persistent risk of dissemination and compromise of bird health and productivity. In this context, the study aimed to investigate the occurrence of different multiresistance phenotypes and the biofilm-forming ability of Enterobacteriaceae isolated from broiler chicken excreta in poultry production units in Ceará, Brazil. Samples were collected from three distinct broiler breeding facilities and subjected to isolation, identification, antibiotic susceptibility testing, phenotypic screening for β-lactamases enzymes, and biofilm formation evaluation. Seventy-one strains were identified, being Escherichia coli (37 %) and Proteus mirabilis (32 %), followed by Klebsiella pneumoniae (11 %), Providencia stuartii (9 %), Klebsiella aerogenes (6 %), Alcaligenes faecalis (4 %), and Salmonella sp. (1 %). A significant proportion (87 %) of multiresistant strains were detected. For the phenotypic evaluation of β-lactamases production, strains with resistance to second and third-generation cephalosporins and carbapenems were tested. About 4 of 6 and 10 of 26 were positive for inducible chromosomal AmpC β-lactamase and extended-spectrum β-lactamase (ESBL), respectively. Regarding biofilm formation, it was observed that all MDR strains were capable of forming biofilm. In this sense the potential of these MDR bacteria to develop biofilms becomes a significant concern, representing a real threat to both human and animal health, as biofilms offer stability, antimicrobial protection, and facilitate genetic transfer.}, }
@article {pmid38972365, year = {2024}, author = {Devi B, A and K V, L and Sugumar, S}, title = {Isolation and characterization of bacteriophages against E.coli urinary tract infection and evaluating their anti-biofilm activity and antibiotic synergy.}, journal = {Microbial pathogenesis}, volume = {193}, number = {}, pages = {106789}, doi = {10.1016/j.micpath.2024.106789}, pmid = {38972365}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Urinary Tract Infections/microbiology ; *Uropathogenic Escherichia coli/drug effects/virology ; *Anti-Bacterial Agents/pharmacology ; Humans ; *Escherichia coli Infections/microbiology ; *Bacteriophages/isolation &amp; purification/physiology ; Phage Therapy ; Myoviridae/isolation &amp; purification/physiology ; Drug Synergism ; Microbial Sensitivity Tests ; }, abstract = {Urinary tract infections (UTIs) by Uropathogenic Escherichia coli (UPEC) are a significant health concern, especially due to the increasing prevalence of antibiotic resistance. This study focuses on isolating and characterizing bacteriophages specific to UPEC strains isolated from UTI samples. The isolated phages were assessed for their ability to target and lyse UPEC in vitro, focusing on their efficacy in disrupting biofilms, a key virulence factor contributing to UTI recurrence and antibiotic resistance. The morphological structure observed by TEM belongs to Myoviridae, the phage exhibited icosahedral symmetry with a long non-constricting tail, the approximate measurement of the phage head was 39 nm in diameter, and the phage tail was 105.317 nm in length. One-step growth experiments showed that the latent period was approximately 20 min, followed by a rise period of 40 min, and a growth plateau was reached within 20 min and the burst size observed was 26 phages/infected bacterial cells. These phages were capable of killing cells within the biofilms, leading to a reduction in living cell counts after a single treatment. This study highlights the potential of phages to play a significant role in disrupting, inactivating, and destroying Uropathogenic Escherichia coli (UPEC) biofilms. Such findings could be instrumental in developing treatment strategies that complement antibiotics and disinfectants. The phage-antibiotic synergistic activity was compared to have the possibility to facilitate the advancement of focused and enduring alternatives to traditional antibiotic therapies for UTIs.}, }
@article {pmid38971825, year = {2024}, author = {Choi, HY and Kim, WG}, title = {Tyrosol blocks E. coli anaerobic biofilm formation via YbfA and FNR to increase antibiotic susceptibility.}, journal = {Nature communications}, volume = {15}, number = {1}, pages = {5683}, pmid = {38971825}, issn = {2041-1723}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Phenylethyl Alcohol/analogs &amp; derivatives/pharmacology ; *Anti-Bacterial Agents/pharmacology ; *Escherichia coli/drug effects ; *Pseudomonas aeruginosa/drug effects/physiology ; *Nitric Oxide/metabolism ; Escherichia coli Proteins/metabolism/genetics/antagonists &amp; inhibitors ; Anaerobiosis/drug effects ; Microbial Sensitivity Tests ; Gene Expression Regulation, Bacterial/drug effects ; Cyclic GMP/metabolism/analogs &amp; derivatives ; Bacterial Proteins/metabolism/genetics/antagonists &amp; inhibitors ; }, abstract = {Bacteria within mature biofilms are highly resistant to antibiotics than planktonic cells. Oxygen limitation contributes to antibiotic resistance in mature biofilms. Nitric oxide (NO) induces biofilm dispersal; however, low NO levels stimulate biofilm formation, an underexplored process. Here, we introduce a mechanism of anaerobic biofilm formation by investigating the antibiofilm activity of tyrosol, a component in wine. Tyrosol inhibits E. coli and Pseudomonas aeruginosa biofilm formation by enhancing NO production. YbfA is identified as a target of tyrosol and its downstream targets are sequentially determined. YbfA activates YfeR, which then suppresses the anaerobic regulator FNR. This suppression leads to decreased NO production, elevated bis-(3'-5')-cyclic dimeric GMP levels, and finally stimulates anaerobic biofilm formation in the mature stage. Blocking YbfA with tyrosol treatment renders biofilm cells as susceptible to antibiotics as planktonic cells. Thus, this study presents YbfA as a promising antibiofilm target to address antibiotic resistance posed by biofilm-forming bacteria, with tyrosol acting as an inhibitor.}, }
@article {pmid38971078, year = {2024}, author = {Ren, Y and Oleszkiewicz, JA and Uyaguari, M and Devlin, TR}, title = {Response and recovery of nitrifying moving bed biofilm reactor systems exposed to 1°C with varying levels of ammonia starvation.}, journal = {Water research}, volume = {261}, number = {}, pages = {122026}, doi = {10.1016/j.watres.2024.122026}, pmid = {38971078}, issn = {1879-2448}, mesh = {*Biofilms ; *Bioreactors ; *Ammonia/metabolism ; *Nitrification ; Temperature ; Waste Disposal, Fluid/methods ; Bacteria/metabolism ; Nitrites/metabolism ; Nitrogen/metabolism ; }, abstract = {This study investigated the impact of varying total ammonia nitrogen (TAN) feed levels along with water temperature decreases on the performance of nitrifying moving bed biofilm reactor (MBBR) at 1 °C and its recovery at 3 °C. Five MBBR reactors were operated with different TAN concentrations as water temperature decreased from 20 to 3 °C: reactor R1 at 30 mg N/L, reactor R2 at 20 mg N/L, reactor R3 at 15 mg N/L, reactor R4 at 10 mg N/L and reactor R5 at 0 mg N/L. The corresponding biofilm characteristics were also analyzed to understand further nitrifying MBBR under different TAN feeding scenarios. The findings revealed that the higher TAN levels were before reaching 1 °C, the better nitrification performance and the more biomass grew. However, the highest TAN concentration (30 mg N/L) might negatively affect the nitrification performance, the activity of nitrifiers, and the growth of biofilms at 1 °C because of the toxic effects of un-ionized or free ammonia (FA). It was observed that the activities of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) were affected by FA concentrations ranging from 0.2 to 0.7 mg N/L at 1 °C, but they could gradually be adapted to such inhibitory environment, with NOB recovering more quickly and robustly than AOB. The study identified 20 mg N/L (67 % of maximum influent TAN at 1 °C in R2 as the optimal TAN feeding concentration, achieving over 90 % TAN removal and a surface area removal rate (SARR) of 0.78 ± 0.02 g N/m[2]·d at 1 °C. Meanwhile, R2 also exhibited the highest biofilm mass, with total solids at 13.3 mg/carrier and volatile solids at 11.3 mg/carrier. As TAN was removed, nitrite accumulation was observed at 1 °C, and higher influent TAN concentrations prior to 1 °C appeared to delay the accumulation. When water temperature increased from 1 °C to 3 °C, nitrification performance improved significantly in all reactors without nitrite accumulation, and the higher TAN feeding in the previous stage led to faster recovery. Compared with 20 °C, biofilm became thinner and denser at 1 °C and 3 °C. Furthermore, this study revealed significant shifts in microbial community composition and nitrifier abundances in response to changes in water temperature and influent TAN levels. The dominant nitrifiers were identified as Nitrosomonadaceae (AOB) and Nitrospiraceae (NOB). At 1 °C, the nitrifier abundances were significantly correlated with SARRs, FA, and biofilm density. R2, which exhibited the best nitrification performance, maintained higher nitrifier abundances at 1 °C.}, }
@article {pmid38971076, year = {2024}, author = {Yu, M and Guo, W and Liang, Y and Xiang, H and Xia, Y and Feng, H}, title = {Towards rapid formation of electroactive biofilm: insights from thermodynamics and electric field manipulation.}, journal = {Water research}, volume = {261}, number = {}, pages = {121992}, doi = {10.1016/j.watres.2024.121992}, pmid = {38971076}, issn = {1879-2448}, mesh = {*Biofilms ; *Thermodynamics ; Electrodes ; Electricity ; Static Electricity ; }, abstract = {Electroactive biofilm (EAB) has garnered significant attention due to its effectiveness in pollutant remediation, electricity generation, and chemical synthesis. However, achieving precise control over the rapid formation of EAB presents challenges for the practical implementation of bioelectrochemical technology. In this study, we investigated the regulation of EAB formation by manipulating applied electric potential. We developed a modified XDLVO model for the applied electric field and quantitatively assessed the feasibility of existing rapid formation strategies for EAB. Our results revealed that electrostatic (EL) force significantly influenced EAB formation in the presence of the applied electric field, with the potential difference between the electrode and the microbial solution being the primary determinant of EL force. Compared to -0.2 V and 0 V vs.Ag/AgCl, EAB exhibited the highest electrochemical performance at 0.2 V vs.Ag/AgCl, with a maximum current density of 6.044 ± 0.10 A/m[2], surpassing that at -0.2 V vs.Ag/AgCl and 0 V vs.Ag/AgCl by 1.73 times and 1.31 times, respectively. Furthermore, EAB demonstrated the highest biomass accumulation, measuring a thickness of 25 ± 2 μm at 0.2 V vs. Ag/AgCl, representing increases of 1.67 and 1.25 times compared to -0.2 V vs.Ag/AgCl and 0 V vs.Ag/AgCl, respectively. The strong electrostatic attraction under the anodic potential promoted the formation of a monolayer of biofilm. Additionally, the hydrophilicity and hydrophobicity of the biofilm were altered following inversion culture. The Lewis acid-base (AB) attraction offset the electrostatic repulsion caused by negative charges, it is beneficial for the formation of biofilms. This study, for the first time, elucidated the difference in the formation of cathode and anode biofilm from a thermodynamic perspective in the context of electric field introduction, laying the theoretical foundation for the directional regulation of the rapid formation of typical electroactive biofilms.}, }
@article {pmid38969785, year = {2024}, author = {Rafique, M and Naveed, M and Mumtaz, MZ and Niaz, A and Alamri, S and Siddiqui, MH and Waheed, MQ and Ali, Z and Naman, A and Rehman, SU and Brtnicky, M and Mustafa, A}, title = {Unlocking the potential of biofilm-forming plant growth-promoting rhizobacteria for growth and yield enhancement in wheat (Triticum aestivum L.).}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {15546}, pmid = {38969785}, issn = {2045-2322}, mesh = {*Triticum/microbiology/growth &amp; development ; *Biofilms/growth &amp; development ; *Rhizosphere ; *Plant Roots/microbiology/growth &amp; development ; *Soil Microbiology ; Bacteria/classification/genetics/metabolism/growth &amp; development/isolation &amp; purification ; Plant Development ; Biomass ; }, abstract = {Plant growth-promoting rhizobacteria (PGPR) boost crop yields and reduce environmental pressures through biofilm formation in natural climates. Recently, biofilm-based root colonization by these microorganisms has emerged as a promising strategy for agricultural enhancement. The current work aims to characterize biofilm-forming rhizobacteria for wheat growth and yield enhancement. For this, native rhizobacteria were isolated from the wheat rhizosphere and ten isolates were characterized for plant growth promoting traits and biofilm production under axenic conditions. Among these ten isolates, five were identified as potential biofilm-producing PGPR based on in vitro assays for plant growth-promoting traits. These were further evaluated under controlled and field conditions for their impact on wheat growth and yield attributes. Surface-enhanced Raman spectroscopy analysis further indicated that the biochemical composition of the biofilm produced by the selected bacterial strains includes proteins, carbohydrates, lipids, amino acids, and nucleic acids (DNA/RNA). Inoculated plants in growth chamber resulted in larger roots, shoots, and increase in fresh biomass than controls. Similarly, significant increases in plant height (13.3, 16.7%), grain yield (29.6, 17.5%), number of tillers (18.7, 34.8%), nitrogen content (58.8, 48.1%), and phosphorus content (63.0, 51.0%) in grains were observed in both pot and field trials, respectively. The two most promising biofilm-producing isolates were identified through 16 s rRNA partial gene sequencing as Brucella sp. (BF10), Lysinibacillus macroides (BF15). Moreover, leaf pigmentation and relative water contents were significantly increased in all treated plants. Taken together, our results revealed that biofilm forming PGPR can boost crop productivity by enhancing growth and physiological responses and thus aid in sustainable agriculture.}, }
@article {pmid38969189, year = {2024}, author = {Hasan, M and Kim, J and Liao, X and Ding, T and Ahn, J}, title = {Antibacterial activity of bacteriophage-encoded endolysins against planktonic and biofilm cells of pathogenic Escherichia coli.}, journal = {Microbial pathogenesis}, volume = {193}, number = {}, pages = {106780}, doi = {10.1016/j.micpath.2024.106780}, pmid = {38969189}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Escherichia coli/drug effects/genetics ; *Endopeptidases/pharmacology/genetics/metabolism ; *Anti-Bacterial Agents/pharmacology ; Hydrogen-Ion Concentration ; Plankton/drug effects/virology ; Coliphages/genetics/physiology ; Lactic Acid/pharmacology ; Bacteriophages/genetics ; Temperature ; Microbial Sensitivity Tests ; Plasmids/genetics ; Viral Proteins/genetics/pharmacology/metabolism ; }, abstract = {This study was designed to assess the possibility of using bacteriophage-encoded endolysins for controlling planktonic and biofilm cells. The endolysins, LysEP114 and LysEP135, were obtained from plasmid vectors containing the endolysin genes derived from Escherichia coli phages. The high identity (>96 %) was observed between LysEP114 and LysEP135. LysEP114 and LysEP135 were characterized by pH, thermal, and lactic acid stability, lytic spectrum, antibacterial activity, and biofilm eradication. The molecular masses of LysEP114 and LysEP135 were 18.2 kDa, identified as muramidases. LysEP114 and LysEP135 showed high lytic activity against the outer membrane-permeabilized E. coli KCCM 40405 at below 37 °C, between pH 5 to 11, and below 70 mM of lactic acid. LysEP114 and LysEP135 showed the broad rang of lytic activity against E. coli KACC 10115, S. Typhimurium KCCM 40253, S. Typhimurium CCARM 8009, tetracycline-resistant S. Typhimurium, polymyxin B-resistant S. Typhimurium, chloramphenicol-resistant S. Typhimurium, K. pneumoniae ATCC 23357, K. pneumoniae CCARM 10237, and Shigella boydii KACC 10792. LysEP114 and LysEP135 effectively reduced the numbers of planktonic E. coli KCCM by 1.7 and 2.1 log, respectively, when treated with 50 mM lactic acid. The numbers of biofilm cells were reduced from 7.3 to 4.1 log CFU/ml and 2.2 log CFU/ml, respectively, when treated with LysEP114- and LysEP135 in the presence of 50 mM lactic acid. The results suggest that the endolysins in combination with lactic acid could be potential alternative therapeutic agents for controlling planktonic and biofilm cells.}, }
@article {pmid38969185, year = {2024}, author = {Jang, JH and Lee, JE and Kim, KT and Ahn, DU and Paik, HD}, title = {Anti-biofilm effect of enzymatic hydrolysates of ovomucin in Listeria monocytogenes and Staphylococcus aureus.}, journal = {Microbial pathogenesis}, volume = {193}, number = {}, pages = {106771}, doi = {10.1016/j.micpath.2024.106771}, pmid = {38969185}, issn = {1096-1208}, mesh = {*Biofilms/drug effects ; *Listeria monocytogenes/drug effects ; *Staphylococcus aureus/drug effects ; *Anti-Bacterial Agents/pharmacology ; *Ovomucin/pharmacology/metabolism ; Hydrolysis ; Bacterial Adhesion/drug effects ; Papain/metabolism ; Microbial Sensitivity Tests ; Chymotrypsin/metabolism ; Protein Hydrolysates/pharmacology/metabolism ; }, abstract = {Despite modern advances in food hygiene, food poisoning due to microbial contamination remains a global problem, and poses a great threat to human health. Especially, Listeria monocytogenes and Staphylococcus aureus are gram-positive bacteria found on food-contact surfaces with biofilms. These foodborne pathogens cause a considerable number of food poisoning and infections annually. Ovomucin (OM) is a water-insoluble gel-type glycoprotein in egg whites. Enzymatic hydrolysis can be used to improve the bioactive properties of OM. This study aimed to investigate whether ovomucin hydrolysates (OMHs) produced using five commercial enzymes (Alcalase®, Bromelain, α-Chymotrypsin, Papain, and Pancreatin) can inhibit the biofilm formation of L. monocytogenes ATCC 15313, L. monocytogenes H7962, S. aureus KCCM 11593, and S. aureus 7. Particularly, OMH prepared with papain (OMPP; 500 μg/mL) significantly inhibited biofilm formation in L. monocytogenes ATCC 15313, L. monocytogenes H7962, S. aureus KCCM 11593, and S. aureus 7 by 85.56 %, 80.28 %, 91.70 %, and 79.00 %, respectively. In addition, OMPP reduced the metabolic activity, exopolysaccharide production (EPS), adhesion ability, and gene expression associated with the biofilm formation of these bacterial strains. These results suggest that OMH, especially OMPP, exerts anti-biofilm effects against L. monocytogenes and S. aureus. Therefore, OMPP can be used as a natural anti-biofilm agent to control food poisoning in the food industry.}, }
@article {pmid38968915, year = {2024}, author = {Eivazzadeh-Keihan, R and Nokandeh, SM and Aliabadi, HAM and Lalebeigi, F and Kashtiaray, A and Mahdavi, M and Sehat, S and Cohan, RA and Maleki, A}, title = {Unveiling the synergy: Biocompatible alginate-cellulose hydrogel loaded with silk fibroin and zinc ferrite nanoparticles for enhanced cell adhesion, and anti-biofilm activity.}, journal = {International journal of biological macromolecules}, volume = {275}, number = {Pt 1}, pages = {133412}, doi = {10.1016/j.ijbiomac.2024.133412}, pmid = {38968915}, issn = {1879-0003}, mesh = {*Alginates/chemistry ; *Fibroins/chemistry/pharmacology ; Humans ; *Hydrogels/chemistry ; *Cell Adhesion/drug effects ; *Cellulose/chemistry/pharmacology ; *Ferric Compounds/chemistry/pharmacology ; *Biocompatible Materials/chemistry/pharmacology ; *Biofilms/drug effects ; *Zinc/chemistry ; Nanoparticles/chemistry ; Fibroblasts/drug effects ; Hemolysis/drug effects ; Cell Line ; }, abstract = {Combining a biocompatible hydrogel scaffold with the cell-supportive properties of silk fibroin (SF) and the unique functionalities of ZnFe2O4 nanoparticles creates a promising platform for advanced nanobiomaterials. The research is centered on synthesizing a natural hydrogel using cellulose (Cellul) and sodium alginate (SA) combined with SF and zinc ferrite nanoparticles. A range of analytical and biological assays were conducted to determine the biological and physicochemical properties of the nanobiocomposite. The hemolysis and 2,5-diphenyl-2H-tetrazolium bromide (MTT) assays indicated that the SA-Cellul hydrogel/SF/ZnFe2O4 nanobiocomposite was a biocompatible against human dermal fibroblasts (Hu02) and red blood cells (RBC). In addition, aside from demonstrating outstanding anti-biofilm activity, the nanobiocomposite also promotes the Hu02 cells adhesion, showcasing the synergistic effect of incorporating SF and ZnFe2O4 nanoparticle. These promising results show that this nanobiocomposite has potential applications in various biomedical fields.}, }
@article {pmid38967798, year = {2024}, author = {Li, M and Cruz, CD and Ilina, P and Tammela, P}, title = {High-throughput combination assay for studying biofilm formation of uropathogenic Escherichia coli.}, journal = {Archives of microbiology}, volume = {206}, number = {8}, pages = {344}, pmid = {38967798}, issn = {1432-072X}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Uropathogenic Escherichia coli/drug effects/physiology ; *High-Throughput Screening Assays/methods ; *Xanthenes/chemistry ; *Anti-Bacterial Agents/pharmacology ; *Gentian Violet/metabolism ; *Oxazines/pharmacology/metabolism/chemistry ; Microbial Sensitivity Tests ; Urinary Tract Infections/microbiology ; Humans ; }, abstract = {Uropathogenic Escherichia coli, the most common cause for urinary tract infections, forms biofilm enhancing its antibiotic resistance. To assess the effects of compounds on biofilm formation of uropathogenic Escherichia coli UMN026 strain, a high-throughput combination assay using resazurin followed by crystal violet staining was optimized for 384-well microplate. Optimized assay parameters included, for example, resazurin and crystal violet concentrations, and incubation time for readouts. For the assay validation, quality parameters Z' factor, coefficient of variation, signal-to-noise, and signal-to-background were calculated. Microplate uniformity, signal variability, edge well effects, and fold shift were also assessed. Finally, a screening with known antibacterial compounds was conducted to evaluate the assay performance. The best conditions found were achieved by using 12 µg/mL resazurin for 150 min and 0.023% crystal violet. This assay was able to detect compounds displaying antibiofilm activity against UMN026 strain at sub-inhibitory concentrations, in terms of metabolic activity and/or biomass.}, }
@article {pmid38966810, year = {2024}, author = {Wani, MY and Srivastava, V and El-Said, WA and Al-Bogami, AS and Ahmad, A}, title = {Inhibition of apoptosis and biofilm formation in Candida auris by click-synthesized triazole-bridged quinoline derivatives.}, journal = {RSC advances}, volume = {14}, number = {29}, pages = {21190-21202}, pmid = {38966810}, issn = {2046-2069}, abstract = {Candida auris, a recent addition to the Candida species, poses a significant threat with its association to numerous hospital outbreaks globally, particularly affecting immunocompromised individuals. Given its resistance to existing antifungal therapies, there is a pressing need for innovative treatments. In this study, novel triazole bridged quinoline derivatives were synthesized and evaluated for their antifungal activity against C. auris. The most promising compound, QT7, demonstrated exceptional efficacy with a minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of 0.12 μg mL[-1] and 0.24 μg mL[-1], respectively. Additionally, QT7 effectively disrupted mature biofilms, inhibiting them by 81.98% ± 8.51 and 89.57 ± 5.47 at MFC and 2× MFC values, respectively. Furthermore, QT7 induced cellular apoptosis in a dose-dependent manner, supported by various apoptotic markers such as phosphatidylserine externalization, mitochondrial depolarization, and reduced cytochrome c and oxidase activity. Importantly, QT7 exhibited low hemolytic activity, highlighting its potential for further investigation. Additionally, the physicochemical properties of this compound suggest its potential as a lead drug candidate, warranting further exploration in drug discovery efforts against Candida auris infections.}, }
@article {pmid38966782, year = {2024}, author = {Rohilla, A and Kumar, V and Ahire, JJ}, title = {Unveiling the persistent threat: recent insights into Listeria monocytogenes adaptation, biofilm formation, and pathogenicity in foodborne infections.}, journal = {Journal of food science and technology}, volume = {61}, number = {8}, pages = {1428-1438}, pmid = {38966782}, issn = {0022-1155}, abstract = {Listeriosis is a severe disease caused by the foodborne pathogen Listeria monocytogenes, posing a significant risk to vulnerable populations such as the elderly, pregnant women, and newborns. While relatively uncommon, it has a high global mortality rate of 20-30%. Recent research indicates that smaller outbreaks of the more severe, invasive form of the disease occur more frequently than previously thought, despite the overall stable infection rates of L. monocytogenes over the past 10 years. The ability of L. monocytogenes to form biofilm structures on various surfaces in food production environments contributes to its persistence and challenges in eradication, potentially leading to contamination of food and food production facilities. To address these concerns, this review focuses on recent developments in epidemiology, risk evaluations, and molecular mechanisms of L. monocytogenes survival in adverse conditions and environmental adaptation. Additionally, it covers new insights into strain variability, pathogenicity, mutations, and host vulnerability, emphasizing the important events framework that elucidates the biochemical pathways from ingestion to infection. Understanding the adaptation approaches of L. monocytogenes to environmental stress factors is crucial for the development of effective and affordable pathogen control techniques in the food industry, ensuring the safety of food production.}, }
@article {pmid38965339, year = {2024}, author = {Nair, VG and Srinandan, CS and Rajesh, YBRD and Narbhavi, D and Anupriya, A and Prabhusaran, N and Nagarajan, S}, title = {Biogenic amine tryptamine in human vaginal probiotic isolates mediates matrix inhibition and thwarts uropathogenic E. coli biofilm.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {15387}, pmid = {38965339}, issn = {2045-2322}, support = {DST/WOS-B/HN-32/2021//Department of Science and Technology, Ministry of Science and Technology, India/ ; 67/5/2020-DDI/BMS//Indian Council of Medical Research/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; Humans ; *Tryptamines/pharmacology ; Female ; *Uropathogenic Escherichia coli/drug effects/physiology ; *Probiotics/pharmacology ; *Vagina/microbiology ; *Lactobacillus/drug effects/metabolism/physiology ; Escherichia coli Infections/microbiology/drug therapy/prevention &amp; control ; Adult ; Anti-Bacterial Agents/pharmacology ; }, abstract = {Probiotics offer a promising prophylactic approach against various pathogens and represent an alternative strategy to combat biofilm-related infections. In this study, we isolated vaginal commensal microbiota from 54 healthy Indian women to investigate their probiotic traits. We primarily explored the ability of cell-free supernatant (CFS) from Lactobacilli to prevent Uropathogenic Escherichia coli (UPEC) colonization and biofilm formation. Our findings revealed that CFS effectively reduced UPEC's swimming and swarming motility, decreased cell surface hydrophobicity, and hindered matrix production by downregulating specific genes (fimA, fimH, papG, and csgA). Subsequent GC-MS analysis identified Tryptamine, a monoamine compound, as the potent bioactive substance from Lactobacilli CFS, inhibiting UPEC biofilms with an MBIC of 4 µg/ml and an MBEC of 8 µg/ml. Tryptamine induced significant changes in E. coli colony biofilm morphology, transitioning from the Red, Dry, and Rough (RDAR) to the Smooth and White phenotype, indicating reduced extracellular matrix production. Biofilm time-kill assays demonstrated a four-log reduction in UPEC viability when treated with Tryptamine, highlighting its potent antibacterial properties, comparable to CFS treatment. Biofilm ROS assays indicated a significant elevation in ROS generation within UPEC biofilms, suggesting a potential antibacterial mechanism. Gene expression studies with Tryptamine-treated samples showed a reduction in expression of curli gene (csgA), consistent with CFS treatment. This study underscores the potential of Tryptamine from probiotic Lactobacilli CFS as a promising antibiofilm agent against UPEC biofilms.}, }
@article {pmid38965139, year = {2024}, author = {Sahin, Z and Ozer, NE and Calı, A}, title = {Biofilm inhibition of denture cleaning tablets and carvacrol on denture bases produced with different techniques.}, journal = {Clinical oral investigations}, volume = {28}, number = {7}, pages = {413}, pmid = {38965139}, issn = {1436-3771}, mesh = {*Biofilms/drug effects ; *Candida albicans/drug effects ; *Denture Bases/microbiology ; *Cymenes/pharmacology ; *Surface Properties ; *Denture Cleansers/pharmacology ; *Materials Testing ; *Microscopy, Electron, Scanning ; Printing, Three-Dimensional ; Tablets ; }, abstract = {OBJECTIVES: This study compares the biofilm inhibition effects of denture cleaning tablets, carvacrol, and their combined use against Candida albicans on denture bases produced with different techniques. Additionally, the surface roughness and contact angles of these denture bases were evaluated.<br><br>MATERIALS AND METHODS: Test samples were prepared from four different denture base materials (cold-polymerized, heat-polymerized, CAD/CAM milling, and 3D-printed). The surface roughness and contact angles of the test samples were measured using a profilometer and goniometer, respectively. For the evaluation of biofilm inhibition, samples were divided into 5 subgroups: Corega and carvacrol, separately and combined treatments, positive (inoculated with C. albicans) and negative control (non-inoculated with C. albicans, only medium). Biofilm mass was determined using the crystal violet method. An additional prepared test sample for each subgroup was examined under scanning electron microscopy (SEM).<br><br>RESULTS: The surface roughness values of the 3D-printed test samples were found to be statistically higher than the other groups (P&#x2009;<&#x2009;.001). The water contact angle of all test materials was not statistically different from each other (P&#x2009;>&#x2009;.001). Corega and carvacrol, separately and combined, significantly decreased the amount of biofilm on all surfaces (P&#x2009;<&#x2009;.0001). Treatment of corega alone and in combination with carvacrol to the 3D-printed material caused less C. albicans inhibition than the other groups (P&#x2009;<&#x2009;.001; P&#x2009;<&#x2009;.05).<br><br>CONCLUSIONS: The surface roughness values of all test groups were within the clinically acceptable threshold. Although Corega and carvacrol inhibited C. albicans biofilms, their combined use did not show a synergistic effect.<br><br>CLINICAL RELEVANCE: Carvacrol may be used as one of the disinfectant agents for denture cleaning due to its biofilm inhibition property.}, }
@article {pmid38965060, year = {2024}, author = {Wu, W and Wang, Y and Yang, H and Chen, H and Wang, C and Liang, J and Song, Y and Xu, S and Sun, Y and Wang, L}, title = {Antibacterial and Biofilm Removal Strategies Based on Micro/Nanomotors in the Biomedical Field.}, journal = {ChemMedChem}, volume = {19}, number = {21}, pages = {e202400349}, doi = {10.1002/cmdc.202400349}, pmid = {38965060}, issn = {1860-7187}, support = {52073071//NSFC/ ; 32271609//NSFC/ ; 22307030//NSFC/ ; YQ2022E021//Natural Science Funding for Excellent Young Scholar of Heilongjiang Province/ ; 2021M700998//China Postdoctoral Science Foundation/ ; LBH-Z21055//Heilongjiang Postdoctoral Foundation/ ; }, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; Humans ; Microbial Sensitivity Tests ; Bacteria/drug effects ; Nanotechnology ; }, abstract = {Bacterial infection, which can trigger varieties of diseases and tens of thousands of deaths each year, poses serious threats to human health. Particularly, the new dilemma caused by biofilms is gradually becoming a severe and tough problem in the biomedical field. Thus, the strategies to address these problems are considered an urgent task at present. Micro/nanomotors (MNMs), also named micro/nanoscale robots, are mostly driven by chemical energy or external field, exhibiting strong diffusion and self-propulsion in the liquid media, which has the potential for antibacterial applications. In particular, when MNMs are assembled in swarms, they become robust and efficient for biofilm removal. However, there is a lack of comprehensive review discussing the progress in this aspect. Bearing it in mind and based on our own research experience in this regard, the studies on MNMs driven by different mechanisms orchestrated for antibacterial activity and biofilm removal are timely and concisely summarized and discussed in this work, aiming to show the advantages of MNMs brought to this field. In addition, an outlook was proposed, hoping to provide the fundamental guidance for future development in this area.}, }
@article {pmid38964021, year = {2024}, author = {Alves, F and Nakada, PJT and Marques, MJAM and Rea, LDC and Cortez, AA and Pellegrini, VOA and Polikarpov, I and Kurachi, C}, title = {Complete photodynamic inactivation of Pseudomonas aeruginosa biofilm with use of potassium iodide and its comparison with enzymatic pretreatment.}, journal = {Journal of photochemistry and photobiology. B, Biology}, volume = {257}, number = {}, pages = {112974}, doi = {10.1016/j.jphotobiol.2024.112974}, pmid = {38964021}, issn = {1873-2682}, mesh = {*Pseudomonas aeruginosa/drug effects/physiology ; *Biofilms/drug effects/radiation effects ; *Potassium Iodide/pharmacology/chemistry ; *Photosensitizing Agents/pharmacology/chemistry ; Light ; Photochemotherapy ; }, abstract = {Pseudomonas aeruginosa, a gram-negative bacterium, accounts for 7% of all hospital-acquired infections. Despite advances in medicine and antibiotic therapy, P. aeruginosa infection still results in high mortality rates of up to 62% in certain patient groups. This bacteria is also known to form biofilms, that are 10 to 1000 times more resistant to antibiotics compared to their free-floating counterparts. Photodynamic Inactivation (PDI) has been proved to be an effective antimicrobial technique for microbial control. This method involves the incubation of the pathogen with a photosensitizer (PS), then, a light at appropriated wavelength is applied, leading to the production of reactive oxygen species that are toxic to the microbial cells. Studies have focused on strategies to enhance the PDI efficacy, such as a pre-treatment with enzymes to degrade the biofilm matrix and/or an addition of inorganic salts to the PS. The aim of the present study is to evaluate the effectiveness of PDI against P. aeruginosa biofilm in association with the application of the enzymes prior to PDI (enzymatic pre-treatment) or the addition of potassium iodide (KI) to the photosensitizer solution, to increase the inactivation effectiveness of the treatment. First, a range of enzymes and PSs were tested, and the best protocols for combined treatments were selected. The results showed that the use of enzymes as a pre-treatment was effective to reduce the total biomass, however, when associated with PDI, mild bacterial reductions were obtained. Then, the use of KI in association with the PS was evaluated and the results showed that, PDI mediated by methylene blue (MB) in the presence of KI was able to completely eradicate the biofilm. However, when the PDI was performed with curcumin and KI, no additive reduction was observed. In conclusion, out of all strategies evaluated in the present study, the most promising strategy to improve PDI against P. aeruginosa biofilm was the use of KI in association with MB, resulting in eradication with 10[8] log bacterial inactivation.}, }
@article {pmid38963508, year = {2024}, author = {Rouhi, A and Falah, F and Azghandi, M and Alizadeh Behbahani, B and Tabatabaei-Yazdi, F and Ibrahim, SA and Dertli, E and Vasiee, A}, title = {Investigating the Effect of Melittin Peptide in Preventing Biofilm Formation, Adhesion and Expression of Virulence Genes in Listeria monocytogenes.}, journal = {Probiotics and antimicrobial proteins}, volume = {}, number = {}, pages = {}, pmid = {38963508}, issn = {1867-1314}, abstract = {Listeria monocytogenes is a notable food-borne pathogen that has the ability to create biofilms on different food processing surfaces, making it more resilient to disinfectants and posing a greater risk to human health. This study assessed melittin peptide's anti-biofilm and anti-pathogenicity effects on L. monocytogenes ATCC 19115. Melittin showed minimum inhibitory concenteration (MIC) of 100 μg/mL against this strain and scanning electron microscopy images confirmed its antimicrobial efficacy. The OD measurement demonstrated that melittin exhibited a strong proficiency in inhibiting biofilms and disrupting pre-formed biofilms at concentrations ranging from 1/8MIC to 2MIC and this amount was 92.59 ± 1.01% to 7.17 ± 0.31% and 100% to 11.50 ± 0.53%, respectively. Peptide also reduced hydrophobicity and self-aggregation of L. monocytogenes by 35.25% and 14.38% at MIC. Melittin also significantly reduced adhesion to HT-29 and Caco-2 cells by 61.33% and 59%, and inhibited invasion of HT-29 and Caco-2 cells by 49.33% and 40.66% for L. monocytogenes at the MIC value. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) revealed melittin's impact on gene expression, notably decreasing inlB (44%) and agrA (45%) gene expression in L. monocytogenes. flaA and hly genes also exhibited reduced expression. Also, significant changes were observed in sigB and prfA gene expression. These results underscore melittin's potential in combating bacterial infections and biofilm-related challenges in the food industry.}, }
@article {pmid38963393, year = {2024}, author = {Zhou, L and Lai, CY and Wu, M and Guo, J}, title = {Simultaneous Biogas Upgrading and Valuable Chemical Production Using Homoacetogens in a Membrane Biofilm Reactor.}, journal = {Environmental science &amp; technology}, volume = {58}, number = {28}, pages = {12509-12519}, doi = {10.1021/acs.est.4c02021}, pmid = {38963393}, issn = {1520-5851}, mesh = {*Biofuels ; *Bioreactors ; *Biofilms ; RNA, Ribosomal, 16S ; Carbon Dioxide/metabolism ; Acetates/metabolism ; }, abstract = {Biogas produced from anaerobic digestion usually contains impurities, particularly with a high content of CO2 (15-60%), thus decreasing its caloric value and limiting its application as an energy source. H2-driven biogas upgrading using homoacetogens is a promising approach for upgrading biogas to biomethane and converting CO2 to acetate simultaneously. Herein, we developed a novel membrane biofilm reactor (MBfR) with H2 and biogas separately supplied via bubbleless hollow fiber membranes. The gas-permeable hollow fibers of the MBfR enabled high H2 and CO2 utilization efficiencies (∼98% and ∼97%, respectively) and achieved concurrent biomethane (∼94%) and acetate (∼450 mg/L/d) production. High-throughput 16S rRNA gene amplicon sequencing suggested that enriched microbial communities were dominated by Acetobacterium (38-48% relative abundance). In addition, reverse transcription quantitative PCR of the functional marker gene formyltetrahydrofolate synthetase showed that its expression level increased with increasing H2 and CO2 utilization efficiencies. These results indicate that Acetobacterium plays a key role in CO2 to acetate conversion. These findings are expected to facilitate energy-positive wastewater treatment and contribute to the development of a new solution to biogas upgrading.}, }
@article {pmid38962288, year = {2024}, author = {Al Ansari, N and Abid, M}, title = {Enhancing Presurgical Infant Orthopedic Appliances: Characterization, Mechanics, and Biofilm Inhibition of a Novel Chlorhexidine-Halloysite Nanotube-Modified PMMA.}, journal = {International journal of biomaterials}, volume = {2024}, number = {}, pages = {6281972}, pmid = {38962288}, issn = {1687-8787}, abstract = {OBJECTIVES: This in vitro study aimed to develop a novel nanocomposite acrylic resin with inherent antimicrobial properties. This study evaluated its effectiveness against microbial biofilm formation, while also assessing its physical and mechanical properties.<br><br>METHODS: Polymethylmethacrylate (PMMA) was modified with four different concentrations of chlorhexidine halloysite nanotubes (CHX-HNTs): 1%, 1.5%, 3%, and 4.5 wt.% by weight, along with a control group (0 wt.% CHX-HNTs). The biofilm inhibition ability of the modified CHX-HNTs acrylic against Candida albicans, Staphylococcus aureus, Streptococcus pneumoniae, and Streptococcus agalactiae was assessed using microtiter biofilm test. In addition, ten samples from each group were then tested for flexural strength, surface roughness, and hardness. Statistical analysis was performed using one-way ANOVA and Tukey's test for comparison (P < 0.05).<br><br>RESULTS: CHX-HNTs effectively reduced the adhesion of Candida albicans and bacteria to the PMMA in a dose-dependent manner. The higher the concentration of CHX-HNTs, the greater the reduction in microbial adhesion, with the highest concentration (4.5 wt.%) showing the most significant effect with inhibition rates &#x2265;98%. The addition of CHX-HNTs at any tested concentration (1%, 1.5%, 3%, and 4.5 wt.%) did not cause any statistically significant difference in the flexural strength, surface roughness, or hardness of the PMMA compared to the control group.<br><br>CONCLUSIONS: The novel integration of CHX-HNT fillers shows promising results as an effective biofilm inhibitor on acrylic appliances. This new approach has the potential to successfully control infectious diseases without negatively affecting the mechanical properties of the acrylic resin. Clinical Relevance. The integration of CHX-HNTs into presurgical infant orthopedic appliances should be thoroughly assessed as a promising preventive measure to mitigate microbial infections. This evaluation holds significant potential for controlling infectious diseases among infants with cleft lip and palate, thereby offering a valuable contribution to their overall well-being.}, }
@article {pmid38961344, year = {2024}, author = {Yu, J and Han, W and Xu, Y and Shen, L and Zhao, H and Zhang, J and Xiao, Y and Guo, Y and Yu, F}, title = {Biofilm-producing ability of methicillin-resistant Staphylococcus aureus clinically isolated in China.}, journal = {BMC microbiology}, volume = {24}, number = {1}, pages = {241}, pmid = {38961344}, issn = {1471-2180}, support = {82202587//The Natural Science Fund of China/ ; }, mesh = {*Methicillin-Resistant Staphylococcus aureus/drug effects/isolation &amp; purification/physiology ; *Biofilms ; China/epidemiology ; *Staphylococcal Infections/epidemiology/microbiology ; Anti-Bacterial Agents/pharmacology ; Genes, Bacterial/genetics ; Humans ; }, abstract = {BACKGROUND: Staphylococcus aureus, a commensal bacterium, colonizes the skin and mucous membranes of approximately 30% of the human population. Apart from conventional resistance mechanisms, one of the pathogenic features of S. aureus is its ability to survive in a biofilm state on both biotic and abiotic surfaces. Due to this characteristic, S. aureus is a major cause of human infections, with Methicillin-Resistant Staphylococcus aureus (MRSA) being a significant contributor to both community-acquired and hospital-acquired infections.<br><br>RESULTS: Analyzing non-repetitive clinical isolates of MRSA collected from seven provinces and cities in China between 2014 and 2020, it was observed that 53.2% of the MRSA isolates exhibited varying degrees of ability to produce biofilm. The biofilm positivity rate was notably high in MRSA isolates from Guangdong, Jiangxi, and Hubei. The predominant MRSA strains collected in this study were of sequence types ST59, ST5, and ST239, with the biofilm-producing capability mainly distributed among moderate and weak biofilm producers within these ST types. Notably, certain sequence types, such as ST88, exhibited a high prevalence of strong biofilm-producing strains. The study found that SCCmec IV was the predominant type among biofilm-positive MRSA, followed by SCCmec II. Comparing strains with weak and strong biofilm production capabilities, the positive rates of the sdrD and sdrE were higher in strong biofilm producers. The genetic determinants ebp, icaA, icaB, icaC, icaD, icaR, and sdrE were associated with strong biofilm production in MRSA. Additionally, biofilm-negative MRSA isolates showed higher sensitivity rates to cefalotin (94.8%), daptomycin (94.5%), mupirocin (86.5%), teicoplanin (94.5%), fusidic acid (81.0%), and dalbavancin (94.5%) compared to biofilm-positive MRSA isolates. The biofilm positivity rate was consistently above 50% in all collected specimen types.<br><br>CONCLUSIONS: MRSA strains with biofilm production capability warrant increased vigilance.}, }
@article {pmid38960353, year = {2024}, author = {Zhang, S and Huang, X and Dong, W and Wang, H and Hu, L and Zhou, G and Zheng, Z}, title = {Potential effects of Cu[2+] stress on nitrogen removal performance, microbial characteristics, and metabolism pathways of biofilm reactor.}, journal = {Environmental research}, volume = {259}, number = {}, pages = {119541}, doi = {10.1016/j.envres.2024.119541}, pmid = {38960353}, issn = {1096-0953}, mesh = {*Biofilms/drug effects ; *Copper/toxicity ; *Bioreactors/microbiology ; *Nitrogen/metabolism ; Denitrification ; Bacteria/metabolism/genetics ; Waste Disposal, Fluid/methods ; }, abstract = {Sequencing batch biofilm reactors (SBBR) were utilized to investigate the impact of Cu[2+] on nitrogen (N) removal and microbial characteristics. The result indicated that the low concentration of Cu[2+] (0.5 mg L[-1]) facilitated the removal of ammonia nitrogen (NH4[+]-N), total nitrogen (TN), nitrate nitrogen (NO3[-]-N), and chemical oxygen demand (COD). In comparison to the average effluent concentration of the control group, the average effluent concentrations of NH4[+]-N, NO3[-]-N, COD, and TN were found to decrease by 40.53%, 17.02%, 10.73%, and 15.86%, respectively. Conversely, the high concentration of Cu[2+] (5 mg L[-1]) resulted in an increase of 94.27%, 55.47%, 22.22%, and 14.23% in the aforementioned parameters, compared to the control group. Low concentrations of Cu[2+] increased the abundance of nitrifying bacteria (Rhodanobacter, unclassified-o-Sacharimonadales), denitrifying bacteria (Thermomonas, Comamonas), denitrification-associated genes (hao, nosZ, norC, nffA, nirB, nick, and nifD), and heavy-metal-resistant genes related to Cu[2+] (pcoB, cutM, cutC, pcoA, copZ) to promote nitrification and denitrification. Conversely, high concentration Cu[2+] hindered the interspecies relationship among denitrifying bacteria genera, nitrifying bacteria genera, and other genera, reducing denitrification and nitrification efficiency. Cu[2+] involved in the N and tricarboxylic acid (TCA) cycles, as evidenced by changes in the abundance of key enzymes, such as (EC:1.7.99.1), (EC:1.7.2.4), and (EC:1.1.1.42), which initially increased and then decreased with varying concentrations of Cu[2+]. Conversely, the abundance of EC1.7.2.1, associated with the accumulation of nitrite nitrogen (NO2[-]-N), gradually declined. These findings provided insights into the impact of Cu[2+] on biological N removal.}, }
@article {pmid38960350, year = {2024}, author = {Ugya, AY and Hasan, DB and Ari, HA and Sheng, Y and Chen, H and Wang, Q}, title = {Antibiotic synergistic effect surge bioenergy potential and pathogen resistance of Chlorella variabilis biofilm.}, journal = {Environmental research}, volume = {259}, number = {}, pages = {119521}, doi = {10.1016/j.envres.2024.119521}, pmid = {38960350}, issn = {1096-0953}, mesh = {*Biofilms/drug effects/radiation effects/growth &amp; development ; *Chlorella/drug effects/metabolism/physiology ; *Anti-Bacterial Agents/pharmacology ; *Ciprofloxacin/pharmacology ; Tetracycline/pharmacology ; Drug Synergism ; }, abstract = {Tetracycline (TC) and ciprofloxacin (CF) induce a synergistic effect that alters the biochemical composition, leading to a decrease in the growth and photosynthetic efficiency of microalgae. But the current study provides a novel insight into stress-inducing techniques that trigger a change in macromolecules, leading to an increase in the bioenergy potential and pathogen resistance of Chlorella variabilis biofilm. The study revealed that in a closed system, a light intensity of 167 μmol/m[2]/s causes 93.5% degradation of TC and 16% degradation of CF after 7 days of exposure, hence availing the products for utilization by C. variabilis biofilm. The resistance to pathogens invasion was linked to 85% and 40% increase in the expression level of photosystem II oxygen-evolving enhancer protein 3 (PsbQ), and mitogen activated kinase (MAK) respectively. The results also indicate that a surge in light intensity triggers 49% increase in the expression level of lysophosphatidylcholine (LPC) (18:2), which is an important lipidomics that can easily undergo transesterification into bioenergy. The thermogravimetric result indicates that the biomass sample of C. variabilis biofilm cultivated under light intensity of 167 μmol/m2/s produces a higher residual mass of 45.5% and 57.5 under air and inert conditions, respectively. The Fourier transform infrared (FTIR) indicates a slight shift in the major functional groups, while the energy-dispersive X-ray spectroscopy (SEM-EDS) and X-ray fluorescence (XRF) indicate clear differences in the morphology and elemental composition of the biofilm biomass in support of the increase bioenergy potential of C. variabilis biofilm. The current study provides a vital understanding of a innovative method of cultivation of C. variabilis biofilm, which is resistant to pathogens and controls the balance between fatty acid and TAG synthesis leading to surge in bioenergy potential and environmental sustainability.}, }
@article {pmid38958241, year = {2024}, author = {Zuo, XS and Wang, QY and Wang, SS and Li, G and Zhan, LY}, title = {The role of N-acetylcysteine on adhesion and biofilm formation of Candida parapsilosis isolated from catheter-related candidemia.}, journal = {Journal of medical microbiology}, volume = {73}, number = {7}, pages = {}, pmid = {38958241}, issn = {1473-5644}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Acetylcysteine/pharmacology ; Humans ; *Candida parapsilosis/drug effects/genetics/physiology ; *Catheter-Related Infections/microbiology ; *Candidemia/microbiology ; Fungal Proteins/genetics/metabolism ; Antifungal Agents/pharmacology ; }, abstract = {Objectives. Anti-fungal agents are increasingly becoming less effective due to the development of resistance. In addition, it is difficult to treat Candida organisms that form biofilms due to a lack of ability of drugs to penetrate the biofilms. We are attempting to assess the effect of a new therapeutic agent, N-acetylcysteine (NAC), on adhesion and biofilm formation in Candida parapsilosis clinical strains. Meanwhile, to detect the transcription level changes of adhesion and biofilm formation-associated genes (CpALS6, CpALS7, CpEFG1 and CpBCR1) when administrated with NAC in C. parapsilosis strains, furthermore, to explore the mechanism of drug interference on biofilms.Hypothesis/Gap statement. N-acetylcysteine (NAC) exhibits certain inhibitory effects on adhesion and biofilm formation in C. parapsilosis clinical strains from CRBSIs through: (1) down-regulating the expression of the CpEFG1 gene, making it a highly potential candidate for the treatment of C. parapsilosis catheter-related bloodstream infections (CRBSIs), (2) regulating the metabolism and biofilm -forming factors of cell structure.Methods. To determine whether non-antifungal agents can exhibit inhibitory effects on adhesion, amounts of total biofilm formation and metabolic activities of C. parapsilosis isolates from candidemia patients, NAC was added to the yeast suspensions at different concentrations, respectively. Reverse transcription was used to detect the transcriptional levels of adhesion-related genes (CpALS6 and CpALS7) and biofilm formation-related factors (CpEFG1 and CpBCR1) in the BCR1 knockout strain, CP7 and CP5 clinical strains in the presence of NAC. To further explore the mechanism of NAC on the biofilms of C. parapsilosis, RNA sequencing was used to calculate gene expression, comparing the differences among samples. Gene Ontology (GO) enrichment analysis helps to illustrate the difference between two particular samples on functional levels.Results. A high concentration of NAC reduces the total amount of biofilm formation in C. parapsilosis. Following co-incubation with NAC, the expression of CpEFG1 in both CP7 and CP5 clinical strains decreased, while there were no significant changes in the transcriptional levels of CpBCR1 compared with the untreated strain. GO enrichment analysis showed that the metabolism and biofilm-forming factors of cell structure were all regulated after NAC intervention.Conclusions. The non-antifungal agent NAC exhibits certain inhibitory effects on clinical isolate biofilm formation by down-regulating the expression of the CpEFG1 gene, making it a highly potential candidate for the treatment of C. parapsilosis catheter-related bloodstream infections.}, }
@article {pmid38955982, year = {2024}, author = {Teixeira, IM and de Moraes Assumpção, Y and Paletta, ACC and Antunes, M and da Silva, IT and Jaeger, LH and Ferreira, RF and de Oliveira Ferreira, E and de Araújo Penna, B}, title = {Investigation on biofilm composition and virulence traits of S. pseudintermedius isolated from infected and colonized dogs.}, journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]}, volume = {55}, number = {3}, pages = {2923-2936}, pmid = {38955982}, issn = {1678-4405}, support = {Coordena&#xe7;&#xe3;o de Aperfei&#xe7;oamento de Pessoal de N&#xed;vel Superior//Coordena&#xe7;&#xe3;o de Aperfei&#xe7;oamento de Pessoal de N&#xed;vel Superior/ ; Conselho Nacional de Desenvolvimento Cient&#xed;fico e Tecnol&#xf3;gico//Conselho Nacional de Desenvolvimento Cient&#xed;fico e Tecnol&#xf3;gico/ ; Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado do Rio de Janeiro//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado do Rio de Janeiro/ ; Bill and Melinda Gates Foundation//Bill and Melinda Gates Foundation/ ; }, mesh = {Animals ; *Biofilms/growth &amp; development ; Dogs ; *Dog Diseases/microbiology ; Virulence/genetics ; *Staphylococcus/genetics/isolation &amp; purification/pathogenicity/classification/physiology ; Staphylococcal Infections/microbiology/veterinary ; Virulence Factors/genetics ; Bacterial Proteins/genetics ; Operon ; }, abstract = {Staphylococcus pseudintermedius, which is part of the skin microbiome of dogs, causes a variety of opportunistic infections. These infections may become more difficult to treat due to the formation of biofilm. The capacity of S. pseudintermedius to form biofilm, as well as the associated genes, has not been elucidated. This study evaluated the production and composition of S. pseudintermedius biofilm. Samples were collected from both infected dogs and asymptomatic dogs. Isolates were identified using mass spectrometry and Multiplex-PCR. Biofilm production and composition were assessed using a quantitative microtiter plate assay. The presence of ica operon genes and sps genes was investigated using conventional PCR. The investigation of Agr type and virulence genes was conducted in silico on 24 sequenced samples. All strains could produce strong biofilms, with most of the isolates presenting a polysaccharide biofilm. 63.6% of the isolates carried the complete ica operon (ADBC). All samples showed the presence of the genes spsK, spsA, and spsL, while the distribution of other genes varied. Agr type III was the most prevalent (52.2%). All sequenced samples carried the cytotoxins hlb, luk-S, luk-F, as well as the exfoliative toxins siet and se_int. No isolate displayed other exfoliative toxins. Only LB1733 presented a set of different enterotoxins (sea, seb, sec_canine, seh, sek, sel, and seq). Our findings suggest that S. pseudintermedius is a strong producer of biofilm and carries virulence genes.}, }
@article {pmid38955904, year = {2024}, author = {Hizlisoy, H and Dishan, A and Bekdik, IK and Barel, M and Koskeroglu, K and Ozkaya, Y and Aslan, O and Yilmaz, OT}, title = {Candida albicans in the oral cavities of pets: biofilm formation, putative virulence, antifungal resistance profiles and classification of the isolates.}, journal = {International microbiology : the official journal of the Spanish Society for Microbiology}, volume = {}, number = {}, pages = {}, pmid = {38955904}, issn = {1618-1905}, abstract = {The study aimed to investigate Candida albicans presence, antifungal resistance, biofilm formation, putative virulence genes, and molecular characterization in oral samples of dogs and cats. A total of 239 oral samples were collected from cats and dogs of various breeds and ages at Erciyes University, Faculty of Veterinary Medicine Clinics, between May 2017 and April 2018. Among 216 isolates obtained, 15 (6.95%) were identified as C. albicans, while 8 (3.7%) were non-albicans Candida species. Antifungal susceptibility testing revealed sensitivities to caspofungin, fluconazole, and flucytosine in varying proportions. Molecular analysis indicated the presence of fluconazole and caspofungin resistance genes in all C. albicans isolates. Additionally, virulence genes ALS1, HWP1, and HSP90 showed variable presence. Biofilm formation varied among isolates, with 46.7% strong, 33.3% moderate, and 20% weak producers. PCA analysis categorized isolates into two main clusters, with some dog isolates grouped separately. The findings underscore the significance of oral care and protective measures in pets due to C. albicans prevalence, biofilm formation, virulence factors, and antifungal resistance in their oral cavity, thereby aiding clinical diagnosis and treatment in veterinary medicine.}, }
@article {pmid38955379, year = {2024}, author = {Fang, Y and Li, Z and Wang, G and Xia, Y and Zhang, K and Gong, W and Yu, E and Xie, W and Li, H and Tian, J and Xie, J and Xu, Q}, title = {Effects of two fillers and process conditions on the water treatment efficiency of a continuous packed bed biofilm reactor.}, journal = {Letters in applied microbiology}, volume = {77}, number = {7}, pages = {}, doi = {10.1093/lambio/ovae060}, pmid = {38955379}, issn = {1472-765X}, support = {2022XT0503//CAFS/ ; 2023A1515012748//Guangdong Basic and Applied Basic Research Foundation/ ; 31802348//National Natural Science Foundation of China/ ; }, mesh = {*Biofilms/growth &amp; development ; *Bioreactors/microbiology ; *Water Purification/methods ; *Wastewater/microbiology/chemistry ; *Aquaculture ; Nitrogen/metabolism ; Charcoal/chemistry ; Bacteria/genetics/isolation &amp; purification/metabolism/growth &amp; development ; Biological Oxygen Demand Analysis ; Microbiota ; Waste Disposal, Fluid/methods ; Water Quality ; }, abstract = {This study evaluated the treatment efficiency of two selected fillers and their combination for improving the water quality of aquaculture wastewater using a packed bed biofilm reactor (PBBR) under various process conditions. The fillers used were nanosheet (NS), activated carbon (AC), and a combination of both. The results indicated that the use of combined fillers and the hydraulic retention time (HRT) of 4 h significantly enhanced water quality in the PBBR. The removal rates of chemical oxygen demand, NO2-─N, total suspended solids（TSS）, and chlorophyll a were 63.55%, 74.25%, 62.75%, and 92.85%, respectively. The microbiota analysis revealed that the presence of NS increased the abundance of microbial phyla associated with nitrogen removal, such as Nitrospirae and Proteobacteria. The difference between the M1 and M2 communities was minimal. Additionally, the microbiota in different PBBR samples displayed similar preferences for carbon sources, and carbohydrates and amino acids were the most commonly utilized carbon sources by microbiota. These results indicated that the combination of NS and AC fillers in a PBBR effectively enhanced the treatment efficiency of aquaculture wastewater when operated at an HRT of 4 h. The findings provide valuable insights into optimizing the design of aquaculture wastewater treatment systems.}, }
@article {pmid38955300, year = {2024}, author = {Qiu, Y and Yang, T and Zhang, H and Dai, H and Gao, H and Feng, W and Xu, D and Duan, J}, title = {The application of pH-responsive hyaluronic acid-based essential oils hydrogels with enhanced anti-biofilm and wound healing.}, journal = {International journal of biological macromolecules}, volume = {275}, number = {Pt 2}, pages = {133559}, doi = {10.1016/j.ijbiomac.2024.133559}, pmid = {38955300}, issn = {1879-0003}, mesh = {*Hyaluronic Acid/chemistry/pharmacology ; *Hydrogels/chemistry/pharmacology ; *Wound Healing/drug effects ; *Biofilms/drug effects ; *Oils, Volatile/pharmacology/chemistry ; Hydrogen-Ion Concentration ; Animals ; *Anti-Bacterial Agents/pharmacology/chemistry ; Chitosan/chemistry/analogs &amp; derivatives/pharmacology ; Staphylococcus aureus/drug effects ; Microbial Sensitivity Tests ; Bandages ; }, abstract = {pH could play vital role in the wound healing process due to the bacterial metabolites, which is one essential aspect of desirable wound dressings lies in being pH-responsive. This work has prepared a degradable hyaluronic acid hydrogel dressing with wound pH response-ability. The aldehyde-modified hyaluronic acid (AHA) was obtained, followed by complex mixture formation of eugenol and oregano antibacterial essential oil in the AHA-CMCS hydrogel through the Schiff base reaction with carboxymethyl chitosan (CMCS). This hydrogel composite presents pH-responsiveness, its disintegration mass in acidic environment (pH = 5.5) is 4 times that of neutral (pH = 7.2), in which the eugenol release rate increases from 37.6 % to 82.1 %. In vitro antibacterial and in vivo wound healing investigations verified that hydrogels loaded with essential oils have additional 5 times biofilm removal efficiency, and significantly accelerate wound healing. Given its excellent anti-biofilm and target-release properties, the broad application of this hydrogel in bacteria-associated wound management is anticipated.}, }
@article {pmid38954220, year = {2024}, author = {Bastos, CG and Livio, DF and de Oliveira, MA and Meira, HGR and Tarabal, VS and Colares, HC and Parreira, AG and Chagas, RCR and Speziali, MG and da Silva, JA and Granjeiro, JM and Millán, RDS and Gonçalves, DB and Granjeiro, PA}, title = {Exploring the biofilm inhibitory potential of Candida sp. UFSJ7A glycolipid on siliconized latex catheters.}, journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]}, volume = {55}, number = {3}, pages = {2119-2130}, pmid = {38954220}, issn = {1678-4405}, support = {#APQ-00855-19//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado de Minas Gerais/ ; RED-00202-22//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado de Minas Gerais/ ; 001//Coordena&#xe7;&#xe3;o de Aperfei&#xe7;oamento de Pessoal de N&#xed;vel Superior/ ; }, mesh = {*Glycolipids/pharmacology/chemistry ; *Biofilms/drug effects/growth &amp; development ; *Surface-Active Agents/pharmacology/chemistry ; *Candida/drug effects/physiology ; *Catheters/microbiology ; Latex/chemistry/pharmacology ; Escherichia coli/drug effects ; Enterococcus faecalis/drug effects/physiology ; Candida albicans/drug effects/physiology ; }, abstract = {Biosurfactants, sustainable alternatives to petrochemical surfactants, are gaining attention for their potential in medical applications. This study focuses on producing, purifying, and characterizing a glycolipid biosurfactant from Candida sp. UFSJ7A, particularly for its application in biofilm prevention on siliconized latex catheter surfaces. The glycolipid was extracted and characterized, revealing a critical micellar concentration (CMC) of 0.98 mg/mL, indicating its efficiency at low concentrations. Its composition, confirmed through Fourier transform infrared spectroscopy (FT-IR) and thin layer chromatography (TLC), identified it as an anionic biosurfactant with a significant ionic charge of -14.8 mV. This anionic nature contributes to its biofilm prevention capabilities. The glycolipid showed a high emulsification index (E24) for toluene, gasoline, and soy oil and maintained stability under various pH and temperature conditions. Notably, its anti-adhesion activity against biofilms formed by Escherichia coli, Enterococcus faecalis, and Candida albicans was substantial. When siliconized latex catheter surfaces were preconditioned with 2 mg/mL of the glycolipid, biofilm formation was reduced by up to 97% for E. coli and C. albicans and 57% for E. faecalis. These results are particularly significant when compared to the efficacy of conventional surfactants like SDS, especially for E. coli and C. albicans. This study highlights glycolipids' potential as a biotechnological tool in reducing biofilm-associated infections on medical devices, demonstrating their promising applicability in healthcare settings.}, }
@article {pmid38951478, year = {2024}, author = {de Menezes, CLA and Boscolo, M and da Silva, R and Gomes, E and da Silva, RR}, title = {Fungal endo and exochitinase production, characterization, and application for Candida biofilm removal.}, journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]}, volume = {55}, number = {3}, pages = {2267-2277}, pmid = {38951478}, issn = {1678-4405}, mesh = {*Biofilms/growth &amp; development ; *Chitinases/metabolism/biosynthesis ; *Chitin/metabolism ; Hydrogen-Ion Concentration ; Temperature ; Hypocreales/enzymology/metabolism ; Candida albicans/enzymology ; Hydrolysis ; Fungal Proteins/metabolism/genetics ; }, abstract = {Chitinases are promising enzymes for a multitude of applications, including chitooligosaccharide (COS) synthesis for food and pharmaceutical uses and marine waste management. Owing to fungal diversity, fungal chitinases may offer alternatives for chitin degradation and industrial applications. The rapid reproduction cycle, inexpensive growth media, and ease of handling of fungi may also contribute to reducing enzyme production costs. Thus, this study aimed to identify fungal species with chitinolytic potential and optimize chitinase production by submerged culture and enzyme characterization using shrimp chitin. Three fungal species, Coriolopsis byrsina, Trichoderma reesei, and Trichoderma harzianum, were selected for chitinase production. The highest endochitinase production was achieved in C. byrsina after 168 h cultivation (0.3 U mL[- 1]). The optimal temperature for enzyme activity was similar for the three fungal species (up to 45 and 55 ºC for endochitinases and exochitinases, respectively). The effect of pH on activity indicated maximum hydrolysis in acidic pH (4-7). In addition, the crude T. reesei extract showed promising properties for removing Candida albicans biofilms. This study showed the possibility of using shrimp chitin to induce chitinase production and enzymes that can be applied in different industrial sectors.}, }
@article {pmid38949961, year = {2024}, author = {Guo, T and Yang, L and Zhou, N and Wang, Z and Huan, C and Zhou, J and Lin, T and Bao, G and Hu, J and Li, G}, title = {Subminimum Inhibitory Concentrations Tetracycline Antibiotics Induce Biofilm Formation in Minocycline-Resistant Klebsiella pneumonia by Affecting Bacterial Physical and Chemical Properties and Associated Genes Expression.}, journal = {ACS infectious diseases}, volume = {10}, number = {8}, pages = {2929-2938}, pmid = {38949961}, issn = {2373-8227}, mesh = {*Biofilms/drug effects ; *Klebsiella pneumoniae/drug effects/genetics ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; Minocycline/pharmacology ; Klebsiella Infections/microbiology/drug therapy ; Gene Expression Regulation, Bacterial/drug effects ; Animals ; Tetracycline/pharmacology ; Bacterial Adhesion/drug effects ; Drug Resistance, Bacterial/drug effects ; Bacterial Proteins/genetics/metabolism ; Moths/drug effects/microbiology ; Humans ; Hydrophobic and Hydrophilic Interactions ; }, abstract = {Biofilm formation of Klebsiella pneumoniae can protect bacteria from antibiotics and is difficult to eradicate. Thus, the influence of subinhibitory concentrations of antibiotics on bacteria is becoming increasingly important. Our study showed that subminimum inhibitory concentrations (sub-MICs) of tetracycline antibiotics can increase biofilm formation in minocycline-resistant Klebsiella pneumoniae clinical strains. However, in the bacterial adhesion and invasion experiments, the adhesion and invasion ability decreased and the survival rate of Galleria mellonella increased. Under sub-MICs of tetracycline antibiotics treatment, abnormal stretching of bacteria was observed by scanning electron microscopy. Treatment with sub-MICs of tetracyclines leads to increased surface hydrophobicity and eDNA content and decreased outer membrane permeability. The expression levels of the fimA, luxS, qseB, and qseC genes decreased, the expression level of mrkA increased, and the expression level of acrA was inconsistent under different tetracycline antibiotics treatments. Together, our results suggested that the increase in Klebsiella pneumoniae biofilm formation caused by sub-MICs of tetracycline antibiotics may occur by affecting bacterial physical and chemical properties and associated genes expression.}, }
@article {pmid38949677, year = {2024}, author = {Riahi, A and Mabudi, H and Tajbakhsh, E and Roomiani, L and Momtaz, H}, title = {Optimizing chitosan derived from Metapenaeus affinis: a novel anti-biofilm agent against Pseudomonas aeruginosa.}, journal = {AMB Express}, volume = {14}, number = {1}, pages = {77}, pmid = {38949677}, issn = {2191-0855}, abstract = {Pseudomonas aeruginosa is a commonly found Gram-negative bacterium in healthcare facilities and is renowned for its ability to form biofilms and its virulence factors that are controlled by quorum sensing (QS) systems. The increasing prevalence of multidrug-resistant strains of this bacterium poses a significant challenge in the field of medicine. Consequently, the exploration of novel antimicrobial agents has become a top priority. This research aims to optimize chitosan derived from white shrimp (Metapenaeus affinis) using the Response Surface Methodology (RSM) computational approach. The objective is to investigate chitosan's potential as a solution for inhibiting QS activity and biofilm formation in P. aeruginosa ATCC 10,145. Under optimized conditions, chitin was treated with NaOH (1.41 M) for 15.75 h, HCl (7.49% vol) for 2.01 h, and at a deacetylation temperature of 81.15 °C. The resulting chitosan exhibited a degree of deacetylation (DD%) exceeding 93.98%, as confirmed by Fourier-transform infrared (FTIR) spectral analysis, indicating its high purity. The extracted chitosan demonstrated a significant synergistic antibiotic effect against P. aeruginosa when combined with ceftazidime, enhancing its bactericidal activity by up to 15-fold. In addition, sub-MIC (minimum inhibitory concentration) concentrations of extracted chitosan (10 and 100 µg/mL) successfully reduced the production of pyocyanin and rhamnolipid, as well as the swimming motility, protease activity and biofilm formation ability in comparison to the control group (P < 0.05). Moreover, chitosan treatment downregulated the RhlR and LasR genes in P. aeruginosa when compared to the control group (P < 0.05). The optimized chitosan extract shows significant potential as a coating agent for surgical equipment, effectively preventing nosocomial infections caused by P. aeruginosa pathogens.}, }
@article {pmid38949302, year = {2024}, author = {Kramara, J and Kim, M-J and Ollinger, TL and Ristow, LC and Wakade, RS and Zarnowski, R and Wellington, M and Andes, DR and Mitchell, AG and Krysan, DJ}, title = {Systematic analysis of the Candida albicans kinome reveals environmentally contingent protein kinase-mediated regulation of filamentation and biofilm formation in vitro and in vivo.}, journal = {mBio}, volume = {15}, number = {8}, pages = {e0124924}, pmid = {38949302}, issn = {2150-7511}, support = {R01 AI133409/AI/NIAID NIH HHS/United States ; R21AI157341//HHS | NIH | National Institute of Allergy and Infectious Diseases (NIAID)/ ; R01AI133409//HHS | NIH | National Institute of Allergy and Infectious Diseases (NIAID)/ ; R01 AI177254/AI/NIAID NIH HHS/United States ; R21 AI157341/AI/NIAID NIH HHS/United States ; }, mesh = {*Candida albicans/genetics/enzymology/pathogenicity/physiology ; *Biofilms/growth &amp; development ; *Protein Kinases/genetics/metabolism ; Virulence ; Animals ; Fungal Proteins/genetics/metabolism ; Candidiasis/microbiology ; Gene Expression Regulation, Fungal ; Mice ; Hyphae/growth &amp; development/genetics ; }, abstract = {Protein kinases are critical regulatory proteins in both prokaryotes and eukaryotes. Accordingly, protein kinases represent a common drug target for a wide range of human diseases. Therefore, understanding protein kinase function in human pathogens such as the fungus Candida albicans is likely to extend our knowledge of its pathobiology and identify new potential therapies. To facilitate the study of C. albicans protein kinases, we constructed a library of 99 non-essential protein kinase homozygous deletion mutants marked with barcodes in the widely used SN genetic background. Here, we describe the construction of this library and the characterization of the competitive fitness of the protein kinase mutants under 11 different growth and stress conditions. We also screened the library for protein kinase mutants with altered filamentation and biofilm formation, two critical virulence traits of C. albicans. An extensive network of protein kinases governs these virulence traits in a manner highly dependent on the specific environmental conditions. Studies on specific protein kinases revealed that (i) the cell wall integrity MAPK pathway plays a condition-dependent role in filament initiation and elongation; (ii) the hyper-osmolar glycerol MAPK pathway is required for both filamentation and biofilm formation, particularly in the setting of in vivo catheter infection; and (iii) Sok1 is dispensable for filamentation in hypoxic environments at the basal level of a biofilm but is required for filamentation in normoxia. In addition to providing a new genetic resource for the community, these observations emphasize the environmentally contingent function of C. albicans protein kinases.IMPORTANCECandida albicans is one of the most common causes of fungal disease in humans for which new therapies are needed. Protein kinases are key regulatory proteins and are increasingly targeted by drugs for the treatment of a wide range of diseases. Understanding protein kinase function in C. albicans pathogenesis may facilitate the development of new antifungal drugs. Here, we describe a new library of 99 protein kinase deletion mutants to facilitate the study of protein kinases. Furthermore, we show that the function of protein kinases in two virulence-related processes, filamentation and biofilm formation, is dependent on the specific environmental conditions.}, }
@article {pmid38946224, year = {2024}, author = {Benny, AT and Thamim, M and Easwaran, N and Gothandam, KM and Thirumoorthy, K and Radhakrishnan, EK}, title = {Attenuation of Quorum Sensing Mediated Virulence Factors and Biofilm Formation in Pseudomonas Aeruginosa PAO1 by Substituted Chalcones and Flavonols.}, journal = {Chemistry &amp; biodiversity}, volume = {21}, number = {8}, pages = {e202400393}, doi = {10.1002/cbdv.202400393}, pmid = {38946224}, issn = {1612-1880}, support = {//VIT management/ ; SG20230044//VIT-SEED GRANT/ ; }, mesh = {*Pseudomonas aeruginosa/drug effects/physiology ; *Quorum Sensing/drug effects ; *Biofilms/drug effects ; *Virulence Factors/metabolism/antagonists &amp; inhibitors ; *Chalcones/pharmacology/chemistry ; *Flavonols/pharmacology/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Molecular Docking Simulation ; Structure-Activity Relationship ; Microbial Sensitivity Tests ; Molecular Structure ; Dose-Response Relationship, Drug ; }, abstract = {Flavonoids epitomize structural scaffolds in many biologically active synthetic and natural compounds. They showcase a diverse spectrum of biological activities including anticancer, antidiabetic, antituberculosis, antimalarial, and antibiofilm activities. The antibiofilm activity of a series of new chalcones and flavonols against clinically significant Pseudomonas aeruginosa PAO1 strain was studied. Antivirulence activities were screened by analysing the effect of compounds on the production of virulence factors like pyocyanin, LasA protease, cell surface hydrophobicity, and rhamnolipid. The best ligands towards the quorum sensing proteins LasR, RhlR, and PqsR were recognised using a molecular docking study. The gene expression in P. aeruginosa after treatment with test compounds was evaluated on quorum sensing genes including rhlA, lasB, and pqsE. The antibiofilm potential of chalcones and flavonols was confirmed by the efficient reduction in the production of virulence factors and downregulation of gene expression.}, }
@article {pmid38946115, year = {2024}, author = {Zayed, N and Vertommen, R and Simoens, K and Bernaerts, K and Boon, N and Srivastava, MG and Braem, A and Van Holm, W and Castro, AB and Teughels, W}, title = {How well do antimicrobial mouth rinses prevent dysbiosis in an in vitro periodontitis biofilm model?.}, journal = {Journal of periodontology}, volume = {95}, number = {9}, pages = {880-891}, doi = {10.1002/JPER.23-0674}, pmid = {38946115}, issn = {1943-3670}, mesh = {*Biofilms/drug effects ; Humans ; *Dysbiosis/prevention &amp; control ; *Mouthwashes/pharmacology/therapeutic use ; *Periodontitis/prevention &amp; control/microbiology ; Microscopy, Electron, Scanning ; Chlorhexidine/pharmacology/analogs &amp; derivatives/therapeutic use ; Interleukin-8 ; In Vitro Techniques ; Anti-Infective Agents/pharmacology/therapeutic use ; Durapatite ; Anti-Infective Agents, Local/pharmacology/therapeutic use ; Microbiota/drug effects ; }, abstract = {BACKGROUND: Periodontal diseases are associated with dysbiosis in the oral microbial communities. Managing oral biofilms is therefore key for preventing these diseases. Management protocols often include over-the-counter antimicrobial mouth rinses, which lack data on their effects on the oral microbiome's ecology, bacterial composition, metabolic activity, and dysbiosis resilience. This study examined the efficacy of antimicrobial mouth rinses to halt dysbiosis in in vitro oral biofilms under periodontitis-simulating conditions.<br><br>METHODS: Multispecies oral biofilms were grown on hydroxyapatite discs (HADs) and rinsed daily with one of six mouth rinses. Positive and negative controls were included. After three rinses, biofilms were analyzed with viability quantitative polymerase chain reaction and visualized using scanning electron microscopy. Supernatants of rinsed biofilms were used for metabolic activity analysis. In addition, human oral keratinocytes were exposed to rinsed biofilms to assess their inflammatory response. All outputs were analyzed for correlation using Spearman coefficient.<br><br>RESULTS: Product-related changes were observed in the rinsed biofilms. Three of the six tested mouth rinses could significantly prevent dysbiosis with &#x2265;30% reduction in pathobiont abundance relative to the control. These biofilms had lower metabolic activity, and the exposed human oral keratinocyte produced less interleukin-8. Interleukin-8 production correlated to both pathobiont quantity and the metabolic activity of the biofilms.<br><br>CONCLUSION: Some mouth rinses could support biofilm resilience and stop dysbiosis evolution in the biofilm model, with a clear product-related effect. Such mouth rinses can be considered for patients under maintenance/supportive periodontal therapy to prevent/delay disease recurrence. Others are more useful for different periodontal therapy stages.}, }
@article {pmid38945827, year = {2024}, author = {Garcia, MT and Namba, AM and do Carmo, PHF and Pedroso, LLC and de Lima, PMN and Gonçale, JC and Junqueira, JC}, title = {Antimicrobial effects of surface pre-reacted glass-ionomer (S-PRG) eluate against oral microcosm biofilm.}, journal = {Biofouling}, volume = {40}, number = {7}, pages = {390-401}, doi = {10.1080/08927014.2024.2371817}, pmid = {38945827}, issn = {1029-2454}, mesh = {*Biofilms/drug effects ; Humans ; *Mouth/microbiology ; Streptococcus mutans/drug effects/growth &amp; development ; Anti-Infective Agents/pharmacology ; Mouthwashes/pharmacology ; Lactic Acid/pharmacology ; Glass Ionomer Cements/pharmacology/chemistry ; Acrylic Resins/pharmacology/chemistry ; Streptococcus/drug effects/physiology ; Surface Properties ; Silicon Dioxide ; }, abstract = {This study investigated the antimicrobial activity of surface pre-reacted glass ionomer eluate (S-PRG) against oral microcosm biofilms collected from the oral cavity of patients. Dental biofilm samples were collected from three volunteers to form microcosm biofilms in vitro. Initially, screening tests were carried out to determine the biofilm treatment conditions with S-PRG eluate. The effects of a daily treatment for 5 min using three microcosm biofilms from different patients was then evaluated. For this, biofilms were formed on tooth enamel specimens for 120 h. Biofilms treated with 100% S-PRG for 5 min per day for 5 days showed a reduction in the number of total microorganisms, streptococci and mutans streptococci. SEM images confirmed a reduction in the biofilm after treatment. Furthermore, S-PRG also reduced lactic acid production. It was concluded that S-PRG eluate reduced the microbial load and lactic acid production in oral microcosm biofilms, reinforcing its promising use as a mouthwash agent.}, }
@article {pmid38945629, year = {2024}, author = {Elafify, M and Liao, X and Feng, J and Ahn, J and Ding, T}, title = {Biofilm formation in food industries: Challenges and control strategies for food safety.}, journal = {Food research international (Ottawa, Ont.)}, volume = {190}, number = {}, pages = {114650}, doi = {10.1016/j.foodres.2024.114650}, pmid = {38945629}, issn = {1873-7145}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Food Safety ; *Food Industry ; *Food Microbiology ; Quorum Sensing/drug effects ; Bacteria/drug effects/growth &amp; development ; Anti-Bacterial Agents/pharmacology ; }, abstract = {Various pathogens have the ability to grow on food matrices and instruments. This grow may reach to form biofilms. Bacterial biofilms are community of microorganisms embedded in extracellular polymeric substances (EPSs) containing lipids, DNA, proteins, and polysaccharides. These EPSs provide a tolerance and favorable living condition for microorganisms. Biofilm formations could not only contribute a risk for food safety but also have negative impacts on healthcare sector. Once biofilms form, they reveal resistances to traditional detergents and disinfectants, leading to cross-contamination. Inhibition of biofilms formation and abolition of mature biofilms is the main target for controlling of biofilm hazards in the food industry. Some novel eco-friendly technologies such as ultrasound, ultraviolet, cold plasma, magnetic nanoparticles, different chemicals additives as vitamins, D-amino acids, enzymes, antimicrobial peptides, and many other inhibitors provide a significant value on biofilm inhibition. These anti-biofilm agents represent promising tools for food industries and researchers to interfere with different phases of biofilms including adherence, quorum sensing molecules, and cell-to-cell communication. This perspective review highlights the biofilm formation mechanisms, issues associated with biofilms, environmental factors influencing bacterial biofilm development, and recent strategies employed to control biofilm-forming bacteria in the food industry. Further studies are still needed to explore the effects of biofilm regulation in food industries and exploit more regulation strategies for improving the quality and decreasing economic losses.}, }
@article {pmid38944284, year = {2024}, author = {Castilla-Sedano, AJ and Zapana-García, J and Valdivia-Del Águila, E and Padilla-Huamantinco, PG and Guerra, DG}, title = {Quantification of early biofilm growth in microtiter plates through a novel image analysis software.}, journal = {Journal of microbiological methods}, volume = {223}, number = {}, pages = {106979}, doi = {10.1016/j.mimet.2024.106979}, pmid = {38944284}, issn = {1872-8359}, mesh = {*Biofilms/growth &amp; development ; *Software ; *Image Processing, Computer-Assisted/methods ; Gentian Violet ; Bacteria/growth &amp; development ; Bacterial Adhesion ; Gentamicins/pharmacology ; }, abstract = {Given the significant impact of biofilms on human health and material corrosion, research in this field urgently needs more accessible techniques to facilitate the testing of new control agents and general understanding of biofilm biology. Microtiter plates offer a convenient format for standardized evaluations, including high-throughput assays of alternative treatments and molecular modulators. This study introduces a novel Biofilm Analysis Software (BAS) for quantifying biofilms from microtiter plate images. We focused on early biofilm growth stages and compared BAS quantification to common techniques: direct turbidity measurement, intrinsic fluorescence detection linked to pyoverdine production, and standard crystal violet staining which enables image analysis and optical density measurement. We also assessed their sensitivity for detecting subtle growth effects caused by cyclic AMP and gentamicin. Our results show that BAS image analysis is at least as sensitive as the standard method of spectrophotometrically quantifying the crystal violet retained by biofilms. Furthermore, we demonstrated that bacteria adhered after short incubations (from 10 min to 4 h), isolated from planktonic populations by a simple rinse, can be monitored until their growth is detectable by intrinsic fluorescence, BAS analysis, or resolubilized crystal violet. These procedures are widely accessible for many laboratories, including those with limited resources, as they do not require a spectrophotometer or other specialized equipment.}, }
@article {pmid38944110, year = {2024}, author = {Di Lodovico, S and Petrini, M and Di Fermo, P and De Pasquale, V and De Martino, L and D'Ercole, S and Nocera, FP and Di Giulio, M}, title = {Staphylococcus pseudintermedius and Pseudomonas aeruginosa Lubbock Chronic Wound Biofilm (LCWB): a suitable dual-species model for in vitro studies.}, journal = {Microbes and infection}, volume = {26}, number = {8}, pages = {105384}, doi = {10.1016/j.micinf.2024.105384}, pmid = {38944110}, issn = {1769-714X}, mesh = {*Biofilms/growth &amp; development ; Animals ; *Pseudomonas aeruginosa/physiology/growth &amp; development ; Dogs ; *Staphylococcus/physiology/isolation &amp; purification/growth &amp; development ; *Wound Infection/microbiology ; *Staphylococcal Infections/microbiology/veterinary ; Disease Models, Animal ; Pseudomonas Infections/microbiology/veterinary ; }, abstract = {Antimicrobial treatment of methicillin-resistant Staphylococcus pseudintermedius associated with canine wounds represents an important challenge. The aim of this study was to create a canine wound infection model, Lubbock Chronic Wound Biofilm (LCWB), with a focus on S. pseudintermedius, drawing inspiration from the established human model involving Staphylococcus aureus. Methicillin-resistant S. pseudintermedius 115 (MRSP) and Pseudomonas aeruginosa 700 strains, isolated from dog wounds, were used to set up the LCWB at 24, 48 and 72 h. The LCWBs were evaluated in terms of volume, weight, and microbial CFU/mg. The microbial spatial distribution in the LCWBs was assessed by SEM and CLSM imaging. The best incubation time for the LCWB production in terms of volume (3.38 cm[3] ± 0.13), weight (0.86 gr ± 0.02) and CFU/mg (up to 7.05 × 10[6] CFU/mg ± 2.89 × 10[5]) was 48 h. The SEM and CLSM images showed a major viable microbial colonization at 48 h with non-mixed bacteria with a prevalence of MRSP on the surface and P. aeruginosa 700 in the depth of the wound. The obtained findings demonstrate the capability of S. pseudintermedius to grow together P. aeruginosa in the LCWB model, representing the suitable model to reproduce the animal chronic wound in vitro.}, }
@article {pmid38943910, year = {2024}, author = {Gong, Y and Zhao, X and Yan, X and Zheng, W and Chen, H and Wang, L}, title = {Gold nanoclusters cure implant infections by targeting biofilm.}, journal = {Journal of colloid and interface science}, volume = {674}, number = {}, pages = {490-499}, doi = {10.1016/j.jcis.2024.06.172}, pmid = {38943910}, issn = {1095-7103}, mesh = {*Biofilms/drug effects ; *Gold/chemistry/pharmacology ; *Metal Nanoparticles/chemistry ; Animals ; Mice ; *Anti-Bacterial Agents/pharmacology/chemistry ; Staphylococcus aureus/drug effects/physiology ; Microbial Sensitivity Tests ; Particle Size ; Infrared Rays ; Surface Properties ; }, abstract = {The biofilm-mediated implant infections pose a huge threat to human health. It is urgent to explore strategies to reverse this situation. Herein, we design 3-amino-1,2,4-triazole-5-thiol (ATT)-modified gold nanoclusters (AGNCs) to realize biofilm-targeting and near-infrared (NIR)-II light-responsive antibiofilm therapy. The AGNCs can interact with the bacterial extracellular DNA through the formation of hydrogen bonds between the amine groups on the ATT and the hydroxyl groups on the DNA. The AGNCs show photothermal properties even at a low power density (0.5 W/cm[2]) for a short-time (5 min) irradiation, making them highly effective in eradicating the biofilm with a dispersion rate up to 90 %. In vivo infected catheter implantation model demonstrates an exceptional high ability of the AGNCs to eradicate approximately 90 % of the bacteria encased within the biofilms. Moreover, the AGNCs show no detectable toxicity or systemic effects in mice. Our study suggests the great potential of the AGNCs for long-term prevention and elimination of the biofilm-mediated infections.}, }
@article {pmid38943859, year = {2024}, author = {Araujo, TT and Dionizio, A and Carvalho, TS and Debortolli, ALB and Vertuan, M and de Souza, BM and Camara, JVF and Henrique-Silva, F and Chiaratti, M and Santos, A and Alves, L and Ferro, M and Magalhães, AC and Buzalaf, MAR}, title = {Acquired pellicle and biofilm engineering with CaneCPI-5: Insights from proteomic and microbiomics analysis.}, journal = {Archives of oral biology}, volume = {166}, number = {}, pages = {106025}, doi = {10.1016/j.archoralbio.2024.106025}, pmid = {38943859}, issn = {1879-1506}, mesh = {*Biofilms ; *Dental Pellicle/microbiology ; Humans ; *Proteomics ; Microbiota ; Male ; Adult ; RNA, Ribosomal, 16S ; Female ; Cystatins ; Proof of Concept Study ; }, abstract = {OBJECTIVE: In this in vivo proof-of-concept study, acquired pellicle engineering was implemented to promote alterations in the protein composition of the acquired enamel pellicle (AEP) and the bacterial composition of the dental biofilm after treatment with Sugarcane cystatin (CaneCPI-5).<br><br>DESIGN: After prophylaxis, 10 volunteers rinsed (10&#xa0;mL, 1&#xa0;min) with the following solutions: 1) deionized water (H2O- negative control or 2) 0.1&#xa0;mg/mL CaneCPI-5. The AEP and biofilm were formed along 2 or 3&#xa0;h, respectively. The AEP was collected with electrode filter papers soaked in 3&#xa0;% citric acid. After protein extraction, samples were analyzed by quantitative shotgun label-free proteomics. The biofilm microbiome was collected with a dental curette. The DNA was extracted, amplified, and analyzed by 16S-rRNA Next Generation Sequencing (NGS).<br><br>RESULTS: Treatment with CaneCPI-5 increased several proteins with antimicrobial, acid-resistance, affinity for hydroxyapatite, structural and calcium binding properties, such as Cysteine-rich-3 (6-fold-p&#xa0;=&#xa0;0.03), Cystatin-B (5.5-fold-p&#xa0;<&#xa0;0.01), Neutrophil-defensin 1 (4.7-fold-p&#xa0;<&#xa0;0.01), Mucin (3.9-fold-p&#xa0;<&#xa0;0.01), Immunoglobulin-heavy-constant (3.8-fold-p&#xa0;<&#xa0;0.01) and Lactotransferrin (2.8-fold-p&#xa0;<&#xa0;0.01). Microbiome revealed that several commensal bacteria had their abundance increased after rinsing with CaneCPI-5, such as Corynebacterium and Neisseria, while Streptococcus and Prevotella nigrescens were decreased. The results indicate the efficiency of CaneCPI-5 in promoting beneficial changes in the AEP and biofilm, making this phytocystatin a potential target for incorporation into dental products.<br><br>CONCLUSION: Cane demonstrated the capability to alter the protein composition of the acquired enamel pellicle (AEP) and the initial colonizers of the biofilm, enhancing the presence of proteins and bacteria crucial for dental protection.}, }
@article {pmid38942710, year = {2024}, author = {Chen, H and Xu, M and Zhang, B and Yu, S and Weir, MD and Melo, MAS and Masri, RM and Tang, Y and Xu, HHK and Yang, D}, title = {Novel strategy of S. mutans gcrR gene over-expression plus antibacterial dimethylaminohexadecyl methacrylate suppresses biofilm acids and reduces dental caries in rats.}, journal = {Dental materials : official publication of the Academy of Dental Materials}, volume = {40}, number = {10}, pages = {e41-e51}, doi = {10.1016/j.dental.2024.06.018}, pmid = {38942710}, issn = {1879-0097}, mesh = {Animals ; Male ; Rats ; *Anti-Bacterial Agents/pharmacology ; Bacterial Proteins/genetics ; *Biofilms/drug effects ; Chlorhexidine/pharmacology ; *Dental Caries/microbiology/drug therapy ; *Methacrylates/pharmacology ; *Microbial Sensitivity Tests ; Rats, Sprague-Dawley ; *Streptococcus mutans/drug effects/genetics ; }, abstract = {OBJECTIVE: Streptococcus mutans (S. mutans) is a major contributor to dental caries, with its ability to synthesize extracellular polysaccharides (EPS) and biofilms. The gcrR gene is a regulator of EPS synthesis and biofilm formation. The objectives of this study were to investigate a novel strategy of combining gcrR gene over-expression with dimethylaminohexadecyl methacrylate (DMAHDM), and to determine their in vivo efficacy in reducing caries in rats for the first time.<br><br>METHODS: Two types of S. mutans were tested: Parent S. mutans; and gcrR gene over-expressed S. mutans (gcrR OE S. mutans). Bacterial minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were measured with DMAHDM and chlorhexidine (CHX). Biofilm biomass, polysaccharide, lactic acid production, live/dead staining, colony-forming units (CFUs), and metabolic activity (MTT) were evaluated. A Sprague-Dawley rat model was used with parent S. mutans and gcrR OE S. mutans colonization to determine caries-inhibition in vivo.<br><br>RESULTS: Drug-susceptibility of gcrR OE S. mutans to DMAHDM or CHX was 2-fold higher than that of parent S. mutans. DMAHDM reduced biofilm CFU by 3-4 logs. Importantly, the combined gcrR OE S. mutans+&#xa0;DMAHDM dual strategy reduced biofilm CFU by 5 logs. In the rat model, the parent S. mutans group had a higher cariogenicity in dentinal (Dm) and extensive dentinal (Dx) regions. The DMAHDM +&#xa0;gcrR OE group reduced the Dm and Dx caries to only 20&#xa0;% and 0&#xa0;%, those of parent S. mutans +&#xa0;PBS control group (p&#xa0;<&#xa0;0.05). The total caries severity of gcrR OE +&#xa0;DMAHDM group was decreased to 51&#xa0;% that of parent S. mutans control (p&#xa0;<&#xa0;0.05).<br><br>SIGNIFICANCE: The strategy of combining S. mutans gcrR over-expression with antibacterial monomer reducing biofilm acids by 97&#xa0;%, and reduced in vivo total caries in rats by 48&#xa0;%. The gcrR over-expression +&#xa0;DMAHDM strategy is promising for a wide range of dental applications to inhibit caries and protect tooth structures.}, }
@article {pmid38942212, year = {2024}, author = {Hu, Z and Li, J and Qian, J and Liu, J and Zhou, W}, title = {Efficacy and mechanisms of rotating algal biofilm system in remediation of soy sauce wastewater.}, journal = {Bioresource technology}, volume = {406}, number = {}, pages = {131047}, doi = {10.1016/j.biortech.2024.131047}, pmid = {38942212}, issn = {1873-2976}, mesh = {*Biofilms ; *Wastewater/chemistry ; *Soy Foods/microbiology ; Biomass ; Biological Oxygen Demand Analysis ; Phosphorus ; Water Purification/methods ; Nitrogen ; Biodegradation, Environmental ; }, abstract = {This study investigated the efficacy of the rotating algal biofilm (RAB) for treating soy sauce wastewater (SW) and its related treatment mechanisms. The RAB system demonstrated superior nutrient removal (chemical oxygen demand, ammonium nitrogen, total nitrogen, and phosphorus for 92 %, 94 %, 91 %, and 82 %, respectively) and biofilm productivity (14 g m[-2] d[-1]) at optimized 5-day harvest time and 2-day hydraulic retention time. This was mainly attributed to the synergistic interactions within the algae-fungi (Apiotrichum)-bacteria (Acinetobacter and Rhizobia) consortium, which effectively assimilated certain extracellular polymeric substances into biomass to enhance algal biofilm growth. Increased algal productivity notably improved protein and essential amino acid contents in the biomass, suggesting a potential for animal feed applications. This study not only demonstrates a sustainable approach for managing SW but also provides insight into the nutrient removal and biomass conversion, offering a viable strategy for large-scale applications in nutrient recovery and wastewater treatment.}, }
@article {pmid38942052, year = {2025}, author = {Ananda, N and Julia, V and Bachtiar, EW}, title = {Limosilactobacillus reuteri DSM 17938 Inhibition of Biofilm Formation by Prevotella intermedia and Fusobacterium nucleatum Across Salivary pH: An In Vitro Study.}, journal = {European journal of dentistry}, volume = {19}, number = {1}, pages = {90-95}, pmid = {38942052}, issn = {1305-7456}, abstract = {OBJECTIVES: This study aims to investigate Limosilactobacillus reuteri DSM 17938's antibiofilm effects on Prevotella intermedia and Fusobacterium nucleatum, common causes of alveolar osteitis. It seeks topical alternatives to prevent this condition posttooth extraction. The secondary objective is to assess these effects under different pH conditions (pH 4.5 and pH 7), mimicking oral cavity saliva pH dynamics.<br><br>MATERIALS AND METHODS: &#x2003;Ethical approval was secured for the saliva collection process involving five healthy adult participants who had undergone wisdom tooth extraction. Saliva samples were diligently collected on the 7th day post-surgery. The unstimulated saliva underwent a series of treatments, including the addition of phenylmethylsulfonyl fluoride (PMSF), pH adjustments, centrifugation, and filtration. The pH levels were re-measured, and subsequent adjustments were made to achieve pH values of 4.5 or 7. Limosilactobacillus reuteri DSM 17938, with a concentration of 1&#xd7;10[8] colony-forming units (CFU) per 5 drops, was utilized in the study. Biofilm testing involved incubating saliva samples with varying pH (4.5 or 7) alongside bacterial suspensions (Prevotella intermedia, Fusobacterium nucleatum, or a mixed species). The Interlac suspension was introduced, and plates were anaerobically incubated for 24 hours. Biofilm results were obtained using a spectrometer. The test is conducted in triplicate.<br><br>STATISTICAL ANALYSIS: &#x2003;To scrutinize the impact of pH on biofilm development, the acquired data underwent a two-way ANOVA test in SPSS as part of the statistical analysis. A significance level of p<0.05 was used to determine statistical significance.<br><br>RESULTS: &#x2003;Limosilactobacillus reuteri DSM 17938 significantly reduced biofilm formation across bacterial strains (p&#x2009;=&#x2009;0.000). Statistical analysis indicated a significant impact of pH on biofilm development (p&#x2009;=&#x2009;0.000) compared to no saliva samples, with higher formation observed under acidic conditions (pH 4.5). However, the pH levels of 4.5 and 7 did not result in significantly different bacterial biofilm formation (p&#x2009;=&#x2009;0.529).<br><br>CONCLUSION: &#x2003;This research highlights Limosilactobacillus reuteri DSM 17938's potency in inhibiting biofilm formation of Prevotella intermedia and Fusobacterium nucleatum. Salivary pH variations significantly influence biofilm development, emphasizing the need to consider pH when assessing probiotic effectiveness. Despite limitations in saliva sample sterilization, this study provides valuable insights into alternative approaches for preventing alveolar osteitis. Further research should explore clinical applications and refine sterilization methods for more accurate results.}, }
@article {pmid38940906, year = {2024}, author = {Zhang, W and Cao, Y and Li, H and Rasmey, AM and Zhang, K and Shi, L and Ge, B}, title = {Membrane protein Bcsdr2 mediates biofilm integrity, hyphal growth and virulence of Botrytis cinerea.}, journal = {Applied microbiology and biotechnology}, volume = {108}, number = {1}, pages = {398}, pmid = {38940906}, issn = {1432-0614}, support = {110202201019(LS-03)//Major Science and Technology Program of China Tobacco Corporation/ ; 32172493//National Natural Science Foundation of China/ ; }, mesh = {*Botrytis/pathogenicity/genetics/growth &amp; development/drug effects ; *Biofilms/growth &amp; development/drug effects ; Virulence ; *Hyphae/growth &amp; development/drug effects ; *Plant Diseases/microbiology ; *Fragaria/microbiology ; *Fungal Proteins/genetics/metabolism ; *Membrane Proteins/genetics/metabolism ; Vitis/microbiology ; Spores, Fungal/growth &amp; development/drug effects/genetics ; Gene Deletion ; }, abstract = {Grey mould caused by Botrytis cinerea is a devastating disease responsible for large losses to agricultural production, and B. cinerea is a necrotrophic model fungal plant pathogen. Membrane proteins are important targets of fungicides and hotspots in the research and development of fungicide products. Wuyiencin affects the permeability and pathogenicity of B. cinerea, parallel reaction monitoring revealed the association of membrane protein Bcsdr2, and the bacteriostatic mechanism of wuyiencin was elucidated. In the present work, we generated and characterised ΔBcsdr2 deletion and complemented mutant B. cinerea strains. The ΔBcsdr2 deletion mutants exhibited biofilm loss and dissolution, and their functional activity was illustrated by reduced necrotic colonisation on strawberry and grape fruits. Targeted deletion of Bcsdr2 also blocked several phenotypic defects in aspects of mycelial growth, conidiation and virulence. All phenotypic defects were restored by targeted gene complementation. The roles of Bcsdr2 in biofilms and pathogenicity were also supported by quantitative real-time RT-PCR results showing that phosphatidylserine decarboxylase synthesis gene Bcpsd and chitin synthase gene BcCHSV II were downregulated in the early stages of infection for the ΔBcsdr2 strain. The results suggest that Bcsdr2 plays important roles in regulating various cellular processes in B. cinerea. KEY POINTS: • The mechanism of wuyiencin inhibits B. cinerea is closely associated with membrane proteins. • Wuyiencin can downregulate the expression of the membrane protein Bcsdr2 in B. cinerea. • Bcsdr2 is involved in regulating B. cinerea virulence, growth and development.}, }
@article {pmid38940862, year = {2024}, author = {Ljaljević Grbić, M and Dimkić, I and Janakiev, T and Kosel, J and Tavzes, &#x10c; and Popović, S and Knežević, A and Legan, L and Retko, K and Ropret, P and Unković, N}, title = {Uncovering the Role of Autochthonous Deteriogenic Biofilm Community: Rožanec Mithraeum Monument (Slovenia).}, journal = {Microbial ecology}, volume = {87}, number = {1}, pages = {87}, pmid = {38940862}, issn = {1432-184X}, support = {451-03-47/2023-01/200178//Ministry of Education, Science, and Technological Development of the Republic of Serbia/ ; 451-03-47/2023-01/200178//Ministry of Education, Science, and Technological Development of the Republic of Serbia/ ; 451-03-47/2023-01/200178//Ministry of Education, Science, and Technological Development of the Republic of Serbia/ ; 451-03-47/2023-01/200178//Ministry of Education, Science, and Technological Development of the Republic of Serbia/ ; 451-03-47/2023-01/200178//Ministry of Education, Science, and Technological Development of the Republic of Serbia/ ; 451-03-47/2023-01/200178//Ministry of Education, Science, and Technological Development of the Republic of Serbia/ ; 451-03-47/2023-01/200178//Ministry of Education, Science, and Technological Development of the Republic of Serbia/ ; 451-03-47/2023-01/200178//Ministry of Education, Science, and Technological Development of the Republic of Serbia/ ; 451-03-47/2023-01/200178//Ministry of Education, Science, and Technological Development of the Republic of Serbia/ ; 451-03-47/2023-01/200178//Ministry of Education, Science, and Technological Development of the Republic of Serbia/ ; 451-03-47/2023-01/200178//Ministry of Education, Science, and Technological Development of the Republic of Serbia/ ; BI-RS/20-21-013 and J7-3147//Slovenian Research Agency (ARRS)/ ; BI-RS/20-21-013 and J7-3147//Slovenian Research Agency (ARRS)/ ; BI-RS/20-21-013 and J7-3147//Slovenian Research Agency (ARRS)/ ; BI-RS/20-21-013 and J7-3147//Slovenian Research Agency (ARRS)/ ; BI-RS/20-21-013 and J7-3147//Slovenian Research Agency (ARRS)/ ; BI-RS/20-21-013 and J7-3147//Slovenian Research Agency (ARRS)/ ; BI-RS/20-21-013 and J7-3147//Slovenian Research Agency (ARRS)/ ; BI-RS/20-21-013 and J7-3147//Slovenian Research Agency (ARRS)/ ; BI-RS/20-21-013 and J7-3147//Slovenian Research Agency (ARRS)/ ; BI-RS/20-21-013 and J7-3147//Slovenian Research Agency (ARRS)/ ; BI-RS/20-21-013 and J7-3147//Slovenian Research Agency (ARRS)/ ; }, mesh = {*Biofilms ; *Lichens/microbiology/physiology ; *Calcium Carbonate ; Slovenia ; Ascomycota/physiology ; Mycobiome ; }, abstract = {The primary purpose of the study, as part of the planned conservation work, was to uncover all aspects of autochthonous biofilm pertaining to the formation of numerous deterioration symptoms occurring on the limestone Rožanec Mithraeum monument in Slovenia. Using state-of-the-art sequencing technologies combining mycobiome data with observations made via numerous light and spectroscopic (FTIR and Raman) microscopy analyses pointed out to epilithic lichen Gyalecta jenensis and its photobiont, carotenoid-rich Trentepohlia aurea, as the origin of salmon-hued pigmented alterations of limestone surface. Furthermore, the development of the main deterioration symptom on the monument, i.e., biopitting, was instigated by the formation of typical endolithic thalli and ascomata of representative Verrucariaceae family (Verrucaria sp.) in conjunction with the oxalic acid-mediated dissolution of limestone. The domination of lichenized fungi, as the main deterioration agents, both on the relief and surrounding limestone, was additionally supported by the high relative abundance of lichenized and symbiotroph groups in FUNGuild analysis. Obtained results not only upgraded knowledge of this frequently occurring but often overlooked group of extremophilic stone heritage deteriogens but also provided a necessary groundwork for the development of efficient biocontrol formulation applicable in situ for the preservation of similarly affected limestone monuments.}, }
@article {pmid38939969, year = {2024}, author = {Tian, L and Zhou, P and Su, Z and Graham, N and Yu, W}, title = {Surface Microstructure Drives Biofilm Formation and Biofouling of Graphene Oxide Membranes in Practical Water Treatment.}, journal = {Environmental science &amp; technology}, volume = {58}, number = {27}, pages = {12281-12291}, doi = {10.1021/acs.est.4c03363}, pmid = {38939969}, issn = {1520-5851}, mesh = {*Biofilms ; *Biofouling ; *Water Purification ; *Graphite/chemistry ; Membranes, Artificial ; Oxides/chemistry ; }, abstract = {Significant progress has been made previously in the research and development of graphene oxide (GO) membranes for water purification, but their biofouling behavior remains poorly understood. In this study, we investigated the biofilm formation and biofouling of GO membranes with different surface microstructures in the context of filtering natural surface water and for an extended operation period (110 days). The results showed that the relatively hydrophilic and smooth Fe(OH)3/GO membrane shaped a thin and spatially heterogeneous biofilm with high stable flux. However, the ability to simultaneously mitigate biofilm formation and reduce biofouling was not observed in the weakly hydrophilic and wrinkled Fe/GO and H-Fe(OH)3/GO membranes. Microbial analyses revealed that the hydrophilicity and roughness distinguished the bacterial communities and metabolic functions. The organic matter-degrading and predatory bacteria were more adapted to hydrophilic and smooth GO surfaces. These functional taxa were involved in the degradation of extracellular polymeric substances (EPS), and improved biofilm heterogeneity. In contrast, the weakly hydrophilic and wrinkled GO surfaces had reduced biodiversity, while unexpectedly boosting the proliferation of EPS-secreting bacteria, resulting in increased biofilm formation and aggravated biofouling. Moreover, all GO membranes achieved sustainable water purification during the entire operating period.}, }
@article {pmid38938883, year = {2024}, author = {Zhu, X and Sculean, A and Eick, S}, title = {In-vitro effects of different hyaluronic acids on periodontal biofilm-immune cell interaction.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1414861}, pmid = {38938883}, issn = {2235-2988}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Hyaluronic Acid/pharmacology/metabolism ; Humans ; *Reactive Oxygen Species/metabolism ; *Fibroblasts/drug effects ; *Cytokines/metabolism ; Monocytes/drug effects/immunology/metabolism ; Periodontal Ligament/cytology/microbiology/drug effects ; Cell Line ; Interleukin-1beta/metabolism ; Interleukin-10/metabolism ; }, abstract = {INTRODUCTION: Recent studies have demonstrated a positive role of hyaluronic acid (HA) on periodontal clinical outcomes. This in-vitro study aimed to investigate the impact of four different HAs on interactions between periodontal biofilm and immune cells.<br><br>METHODS: The four HAs included: high-molecular-weight HA (HHA, non-cross-linked), low-molecular-weight HA (LHA), oligomers HA (OHA), and cross-linked high-molecular-weight HA (CHA). Serial experiments were conducted to verify the influence of HAs on: (i) 12-species periodontal biofilm (formation and pre-existing); (ii) expression of inflammatory cytokines and HA receptors in monocytic (MONO-MAC-6) cells and periodontal ligament fibroblasts (PDLF) with or without exposure to periodontal biofilms; (iii) generation of reactive oxygen species (ROS) in MONO-MAC-6 cells and PDLF with presence of biofilm and HA.<br><br>RESULTS: The results indicated that HHA and CHA reduced the bacterial counts in a newly formed (4-h) biofilm and in a pre-existing five-day-old biofilm. Without biofilm challenge, OHA triggered inflammatory reaction by increasing IL-1&#x3b2; and IL-10 levels in MONO-MAC cells and IL-8 in PDLF in a time-dependent manner, whereas CHA suppressed this response by inhibiting the expression of IL-10 in MONO-MAC cells and IL-8 in PDLF. Under biofilm challenge, HA decreased the expression of IL-1&#x3b2; (most decreasing HHA) and increased IL-10 levels in MONO-MAC-6 cells in a molecular weight dependent manner (most increasing CHA). The interaction between HA and both cells may occur via ICAM-1 receptor. Biofilm stimulus increased ROS levels in MONO-MAC-6 cells and PDLF, but only HHA slightly suppressed the high generation of ROS induced by biofilm stimulation in both cells.<br><br>CONCLUSION: Overall, these results indicate that OHA induces inflammation, while HHA and CHA exhibit anti-biofilm, primarily anti-inflammatory, and antioxidant properties in the periodontal environment.}, }
@article {pmid38938878, year = {2024}, author = {Van Nederveen, V and Melton-Celsa, A}, title = {Extracellular components in enteroaggregative Escherichia coli biofilm and impact of treatment with proteinase K, DNase or sodium metaperiodate.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1379206}, pmid = {38938878}, issn = {2235-2988}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Endopeptidase K/pharmacology/metabolism ; *Escherichia coli/drug effects/genetics ; *Deoxyribonucleases/metabolism/pharmacology ; Fimbriae, Bacterial/metabolism ; Bacterial Adhesion/drug effects ; Humans ; Periodic Acid/pharmacology ; }, abstract = {Enteroaggregative E. coli (EAEC) is a major cause of diarrhea worldwide. EAEC are highly adherent to cultured epithelial cells and make biofilms. Both adherence and biofilm formation rely on the presence of aggregative adherence fimbriae (AAF). We compared biofilm formation from two EAEC strains of each of the five AAF types. We found that AAF type did not correlate with the level of biofilm produced. Because the composition of the EAEC biofilm has not been fully described, we stained EAEC biofilms to determine if they contained protein, carbohydrate glycoproteins, and/or eDNA and found that EAEC biofilms contained all three extracellular components. Next, we assessed the changes to the growing or mature EAEC biofilm mediated by treatment with proteinase K, DNase, or a carbohydrate cleavage agent to target the different components of the matrix. Growing biofilms treated with proteinase K had decreased biofilm staining for more than half of the strains tested. In contrast, although sodium metaperiodate only altered the biofilm in a quantitative way for two strains, images of biofilms treated with sodium metaperiodate showed that the EAEC were more spread out. Overall, we found variability in the response of the EAEC strains to the treatments, with no one treatment producing a biofilm change for all strains. Finally, once formed, mature EAEC biofilms were more resistant to treatment than biofilms grown in the presence of those same treatments.}, }
@article {pmid38936698, year = {2024}, author = {Zhao, X and Höfte, M and Spanoghe, P and Rajkovic, A and Uyttendaele, M}, title = {Biofilm-forming Ability of Bacillus thuringiensis Strains from Biopesticides on Polystyrene and their Attachment on Spinach.}, journal = {Journal of food protection}, volume = {87}, number = {8}, pages = {100321}, doi = {10.1016/j.jfp.2024.100321}, pmid = {38936698}, issn = {1944-9097}, mesh = {*Bacillus thuringiensis/classification/physiology ; Bacillus cereus/physiology ; Biological Control Agents ; *Spinacia oleracea/microbiology ; Polystyrenes ; *Biofilms ; Spores, Bacterial/growth &amp; development/physiology ; Species Specificity ; *Bacterial Adhesion ; }, abstract = {Bacillus thuringiensis-based commercial products as a biopesticide have been used for more than 60 years in agriculture. However, as one of the species in B. cereus group, B. thuringiensis has been considered as an emerging hazard with the potential to cause food toxico-infections. The present study aimed to evaluate the biofilm-forming ability of B. thuringiensis biopesticide strains and their attachment on spinach, compared to foodborne B. cereus strains. Biofilm formations of tested strains were found to be strain-specific and affected by the nutrient conditions more than the incubation time. Nutrient starvation conditions generally reduced the biofilm formation of tested B. thuringiensis and B. cereus strains, particularly B. thuringiensis ABTS-1857 strain was found as the nonbiofilm former in starvation conditions. It is worth mentioning that B. thuringiensis SA-11 strain showed stronger biofilm-forming ability with more air-liquid interface biofilm than the other two B. thuringiensis biopesticide strains, but no such higher attachment of B. thuringiensis SA-11 to spinach was observed. These results indicate that B. thuringiensis SA-11 strain can enter the food processing lines by the attachment on spinach leaves, and it has the potential to form biofilms throughout the processing lines or the production environment when sufficient nutrients are available. However, more biofilm tests of B. thuringiensis biopesticide strains in the vegetable production chain should be performed. The dry formulation of commercial B. thuringiensis biopesticides enhanced their adhesion on spinach leaves, whereas the strength of adhesion was not improved by the formulation. In addition, 1-2 log reductions of spores after the intensive washing of spinach leaves in the lab were detected. However, the log reduction due to the actual washing done by the food processing companies in large-volume washing baths or by consumers at home would be limited and less than this lab simulation.}, }
@article {pmid38936065, year = {2024}, author = {Zhao, Z and Gao, B and Yang, C and Wu, Y and Sun, C and Jiménez, N and Zheng, L and Huang, F and Ren, Z and Yu, Z and Yu, C and Zhang, J and Cai, M}, title = {Stimulating the biofilm formation of Bacillus populations to mitigate soil antibiotic resistome during insect fertilizer application.}, journal = {Environment international}, volume = {190}, number = {}, pages = {108831}, doi = {10.1016/j.envint.2024.108831}, pmid = {38936065}, issn = {1873-6750}, mesh = {*Fertilizers ; *Biofilms/drug effects ; *Soil Microbiology ; Animals ; *Bacillus/physiology/genetics ; Soil/chemistry ; Anti-Bacterial Agents/pharmacology ; Drug Resistance, Microbial/genetics ; Agriculture/methods ; Microbiota/drug effects ; }, abstract = {Antibiotic resistance in soil introduced by organic fertilizer application pose a globally recognized threat to human health. Insect organic fertilizer may be a promising alternative due to its low antibiotic resistance. However, it is not yet clear how to regulate soil microbes to reduce antibiotic resistance in organic fertilizer agricultural application. In this study, we investigated soil microbes and antibiotic resistome under black soldier fly organic fertilizer (BOF) application in pot and field systems. Our study shows that BOF could stimulate ARB (antibiotic resistant - bacteria) - suppressive Bacillaceae in the soil microbiome and reduce antibiotic resistome. The carbohydrate transport and metabolism pathway of soil Bacillaceae was strengthened, which accelerated the synthesis and transport of polysaccharides to form biofilm to antagonistic soil ARB, and thus reduced the antibiotic resistance. We further tested the ARB - suppressive Bacillus spp. in a microcosm assay, which resulted in a significant decrease in the presence of ARGs and ARB together with higher abundance in key biofilm formation gene (epsA). This knowledge might help to the development of more efficient bio-fertilizers aimed at mitigating soil antibiotic resistance and enhancing soil health, in particular, under the requirements of global "One Health".}, }
@article {pmid38935316, year = {2024}, author = {Lee, D and Im, J and Kim, AR and Jun, W and Yun, CH and Han, SH}, title = {Enterococcus Phage vB_EfaS_HEf13 as an Anti-Biofilm Agent Against Enterococcus faecalis.}, journal = {Journal of microbiology (Seoul, Korea)}, volume = {62}, number = {8}, pages = {683-693}, pmid = {38935316}, issn = {1976-3794}, support = {NRF-2018R1A5A2024418//National Research Foundation of Korea/ ; NRF-2022M3A9F3082330//National Research Foundation of Korea/ ; NRF-2023R1A2C1004987//National Research Foundation of Korea/ ; RS-2022-00164722//National Research Foundation of Korea/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Enterococcus faecalis/virology/drug effects/physiology ; *Bacteriophages/physiology ; Humans ; Anti-Bacterial Agents/pharmacology ; Chlorhexidine/pharmacology ; Phage Therapy ; Gram-Positive Bacterial Infections/microbiology ; Periapical Periodontitis/therapy/microbiology/virology ; Polysaccharides, Bacterial/metabolism ; }, abstract = {Enterococcus faecalis is a Gram-positive bacterium that is frequently found in the periapical lesion of patients with apical periodontitis. Its biofilm formation in root canal is closely related to the development of refractory apical periodontitis by providing increased resistance to endodontic treatments. Phage therapy has recently been considered as an efficient therapeutic strategy in controlling various periodontal pathogens. We previously demonstrated the bactericidal capacities of Enterococcus phage vB_EfaS_HEf13 (phage HEf13) against clinically-isolated E. faecalis strains. Here, we investigated whether phage HEf13 affects biofilm formation and pre-formed biofilm of clinically-isolated E. faecalis, and its combinatory effect with endodontic treatments, including chlorhexidine (CHX) and penicillin. The phage HEf13 inhibited biofilm formation and disrupted pre-formed biofilms of E. faecalis in a dose- and time-dependent manner. Interestingly, phage HEf13 destroyed E. faecalis biofilm exopolysaccharide (EPS), which is known to be a major component of bacterial biofilm. Furthermore, combined treatment of phage HEf13 with CHX or penicillin more potently inhibited biofilm formation and disrupted pre-formed biofilm than either treatment alone. Confocal laser scanning microscopic examination demonstrated that these additive effects of the combination treatments on disruption of pre-formed biofilm are mediated by relatively enhanced reduction in thickness distribution and biomass of biofilm. Collectively, our results suggest that the effect of phage HEf13 on E. faecalis biofilm is mediated by its EPS-degrading property, and its combination with endodontic treatments more potently suppresses E. faecalis biofilm, implying that phage HEf13 has potential to be used as a combination therapy against E. faecalis infections.}, }
@article {pmid38934606, year = {2024}, author = {Huang, Y-L and Huang, C-H and Huang, Y-C and Yen, C-L and Hsu, C-R}, title = {Anti-biofilm activities and antibiotic synergy of naturally occurring compounds against drug-resistant rapidly growing mycobacteria.}, journal = {Microbiology spectrum}, volume = {12}, number = {8}, pages = {e0019924}, pmid = {38934606}, issn = {2165-0497}, abstract = {UNLABELLED: Some naturally occurring compounds, known for their antimicrobial activities, have been employed as food additives. However, their efficacy in treating infections caused by antibiotic-resistant bacteria is yet to be fully explored. Rapidly growing mycobacteria (RGM), a category within nontuberculous mycobacteria (NTM), are prevalent in various environments and can lead to infections in humans. The rise of antimicrobial resistance within RGM is a documented concern. In this study, we reported that four specific natural compounds effectively inhibited the growth and biofilm formation of three key RGM pathogens M. abscessus, M. fortuitum, and M. chelonae. We screened 12 natural compounds for their effectiveness against antibiotic-resistant clinical strains of RGM. Four compounds showed significant inhibitory effects from the most effective to least: trans-cinnamaldehyde, carvacrol, gentisaldehyde, and phloroglucinaldehyde. In the analysis of time-killing kinetics, gentisaldehyde and phloroglucinaldehyde displayed bactericidal activity while trans-cinnamaldehyde and carvacrol exhibited bacteriostatic effects. At 1× minimal inhibition concentrations, these compounds significantly reduced biofilm formation in all three RGM species to levels between 2.9% and 20.5% relative to controls. Checkerboard assays indicated synergistic interactions between these four compounds and antibiotics such as amikacin, clarithromycin, and linezolid. Of these 12 compound-antibiotic combinations, the pairs of carvacrol-linezolid, carvacrol-amikacin, and gentisaldehyde-clarithromycin demonstrated the most synergy against multiple RGM strains. Moreover, two other compounds citral and geraniol showed synergism with all three test antibiotics. Time-killing assays further confirmed most of synergistic combinations identified in the checkerboard tests. Our research suggests the potential of these essential oils and phenolic aldehydes, both individually and in combination with antibiotics, in treating RGM infections. In addition, this work illuminates applications of these natural compounds in environmental remediation to mitigate bacterial persistence for the control of infectious diseases.<br><br>IMPORTANCE: The emergence of antimicrobial resistance within rapidly growing mycobacteria (RGM) poses a significant threat to public health. This study investigates the potential of naturally occurring compounds to combat infections caused by antibiotic-resistant RGM including M. abscessus, M. fortuitum, and M. chelonae. We identified four specific natural compounds showing impressive inhibitory effects against antibiotic-resistant clinical strains. These compounds not only inhibited the growth and biofilm formation but also exhibited synergistic interactions with antibiotics against key RGM pathogens. Our findings highlight the alternative treatment strategies for RGM infections and potential environmental applications of these natural compounds in mitigating microbial persistence and controlling infectious diseases.}, }
@article {pmid38934251, year = {2024}, author = {Teng, JL and Tang, Y and Wong, SS and Yeung, ML and Cai, JP and Chen, C and Chan, E and Fong, JY and Au-Yeung, RK and Xiong, L and Lau, TC and Lau, SK and Woo, PC}, title = {Mycolyltransferase is important for biofilm formation and pathogenesis of Tsukamurella keratitis.}, journal = {Emerging microbes &amp; infections}, volume = {13}, number = {1}, pages = {2373317}, pmid = {38934251}, issn = {2222-1751}, mesh = {*Biofilms/growth &amp; development ; Animals ; Rabbits ; *Keratitis/microbiology ; *Disease Models, Animal ; Virulence Factors/genetics/metabolism ; Actinomycetales Infections/microbiology/veterinary ; Bacterial Proteins/genetics/metabolism ; Whole Genome Sequencing ; Eye Infections, Bacterial/microbiology ; Genome, Bacterial ; Humans ; }, abstract = {Tsukamurella, a group of multi-drug resistant, Gram-positive, aerobic, and partially acid-fast bacteria, are emerging causes of bacterial conjunctivitis and keratitis. However, the pathogenesis of Tsukamurella keratitis is largely unknown. To address this, we used New Zealand White rabbits to develop the first eye infection model and conducted in vitro tests to study the pathogenesis mechanisms of Tsukamurella. There is increasing evidence that biofilms play a significant role in ocular infections, leading us to hypothesize that biofilm formation is crucial for effective Tsukamurella infection. In order to look for potential candidate genes which are important in biofilm formation and Tsukamurella keratitis. We performed genome sequencing of two ocular isolates, T. pulmonis-PW1004 and T. tyrosinosolvens-PW899, to identify potential virulence factors. Through in vitro and in vivo studies, we characterized their biological roles in mediating Tsukamurella keratitis. Our findings confirmed that Tsukamurella is an ocular pathogen by fulfilling Koch's postulates, and using genome sequence data, we identified tmytC, encoding a mycolyltransferase, as a crucial gene in biofilm formation and causing Tsukamurella keratitis in the rabbit model. This is the first report demonstrating the novel role of mycolyltransferase in causing ocular infections. Overall, our findings contribute to a better understanding of Tsukamurella pathogenesis and provide a potential target for treatment. Specific inhibitors targeting TmytC could serve as an effective treatment option for Tsukamurella infections.}, }
@article {pmid38933776, year = {2024}, author = {Wu, X and Wu, D and Cui, G and Lee, KH and Yang, T and Zhang, Z and Liu, Q and Zhang, J and Chua, EG and Chen, Z}, title = {Association Between Biofilm Formation and Structure and Antibiotic Resistance in H. pylori.}, journal = {Infection and drug resistance}, volume = {17}, number = {}, pages = {2501-2512}, pmid = {38933776}, issn = {1178-6973}, abstract = {BACKGROUND: Persistent infections caused by Helicobacter pylori (H. pylori), which are resistant to antibiotic treatment, pose a growing global public health concern. Biofilm formation is known to be associated with persistent infections due to its role in enhancing antimicrobial resistance and the tolerance of many pathogenic bacteria.<br><br>OBJECTIVE: This study aims to evaluate the biofilm formation of clinical isolates of H. pylori and its impact on antibiotic eradication.<br><br>METHODS: The thickness, morphology, and structure of biofilms derived from nine H. pylori strains were examined using confocal laser scanning microscopy, scanning electron microscopy, and transmission electron microscopy. Subsequently, the susceptibility of both planktonic and biofilm bacteria was assessed through the determination of minimum inhibitory concentration and minimum biofilm eradication concentration for amoxicillin, clarithromycin, levofloxacin, and tetracycline.<br><br>RESULTS: The results revealed varying biofilm thicknesses and densities among the strains, characterised by the presence of numerous filaments intertwining and connecting bacterial cells. Additionally, several cases exhibited susceptibility based on MIC measurements but resistance according to MBEC measurements, with MBEC indicating a higher resistance rate. Pearson Correlation analysis demonstrated a positive correlation between biofilm thickness and MBEC results (0 < r < 1), notably significant for amoxicillin (r = 0.801, P = 0.009) and tetracycline (r = 0.696, P = 0.037).<br><br>CONCLUSION: Different strains of H. pylori exhibit variations in their capacity to release outer membrane vesicles (OMVs) and form biofilms. Biofilm formation can influence the effectiveness of amoxicillin and tetracycline in eradicating susceptible bacterial strains.}, }
@article {pmid38932188, year = {2024}, author = {Alipour-Khezri, E and Moqadami, A and Barzegar, A and Mahdavi, M and Skurnik, M and Zarrini, G}, title = {Bacteriophages and Green Synthesized Zinc Oxide Nanoparticles in Combination Are Efficient against Biofilm Formation of Pseudomonas aeruginosa.}, journal = {Viruses}, volume = {16}, number = {6}, pages = {}, pmid = {38932188}, issn = {1999-4915}, mesh = {*Zinc Oxide/pharmacology ; *Pseudomonas aeruginosa/virology/drug effects/physiology ; *Biofilms/drug effects ; *Metal Nanoparticles/chemistry ; Green Chemistry Technology ; Bacteriophages/physiology ; Anti-Bacterial Agents/pharmacology ; Nanoparticles/chemistry ; }, abstract = {Bacteriophages (phages) are viruses that infect the bacteria within which their reproduction cycle takes place, a process that ends in the lysis and death of the bacterial cell. Some phages are also able to destroy bacterial biofilms. Due to increased antibiotics resistance, Pseudomonas aeruginosa, another biofilm-forming pathogen, is a problem in many parts of the world. Zinc oxide (ZnO) and other metal nanoparticles (NPs) are biologically active and also possess anti-biofilm properties. ZnO-NPs were prepared by the green synthesis method using orange peels. The vibrational peaks of the ZnO-NPs were analyzed using FTIR analysis, and their size and morphological properties were determined using scanning electron microscopy (SEM). The ability of the ZnO-NPs to reduce or eliminate P. aeruginosa biofilm alone or in combination with phages PB10 and PA19 was investigated. The P. aeruginosa cells were effectively killed in the preformed 48 h biofilms during a 24 h incubation with the ZnO-NP-phage combination, in comparison with the control or ZnO-NPs alone. The treatments on growing biofilms were most efficient in the final stages of biofilm development. All five treatment groups showed a significant biofilm reduction compared to the control group (p < 0.0001) at 48 h of incubation. The influence of the ZnO-NPs and phages on the quorum sensing system of P. aeruginosa was monitored by quantitative real-time PCR (qRT-PCR) of the autoinducer biosynthesis gene lasI. While the ZnO-NPs repressed the lasI gene transcription, the phages slightly activated it at 24 and 48 h of incubation. Also, the effect of the ZnO-NPs and phage PA19 on the viability of HFF2 cells was investigated and the results showed that the combination of NPs with PA19 reduced the toxic effect of ZnO-NPs and also stimulated the growth in normal cells.}, }
@article {pmid38932022, year = {2024}, author = {Hwang, JJ and Chen, PY and Luo, KH and Wang, YC and Lai, TY and Balitaan, JNI and Lin, SR and Yeh, JM}, title = {Leaf on a Film: Mesoporous Silica-Based Epoxy Composites with Superhydrophobic Biomimetic Surface Structure as Anti-Corrosion and Anti-Biofilm Coatings.}, journal = {Polymers}, volume = {16}, number = {12}, pages = {}, pmid = {38932022}, issn = {2073-4360}, abstract = {In this study, a series of amine-modified mesoporous silica (AMS)-based epoxy composites with superhydrophobic biomimetic structure surface of Xanthosoma sagittifolium leaves (XSLs) were prepared and applied as anti-corrosion and anti-biofilm coatings. Initially, the AMS was synthesized by the base-catalyzed sol-gel reaction of tetraethoxysilane (TEOS) and triethoxysilane (APTES) through a non-surfactant templating route. Subsequently, a series of AMS-based epoxy composites were prepared by performing the ring-opening polymerization of DGEBA with T-403 in the presence of AMS spheres, followed by characterization through FTIR, TEM, and CA. Furthermore, a nano-casting technique with polydimethylsiloxane (PDMS) as the soft template was utilized to transfer the surface pattern of natural XSLs to AMS-based epoxy composites, leading to the formation of AMS-based epoxy composites with biomimetic structure. From a hydrophilic CA of 69°, the surface of non-biomimetic epoxy significantly increased to 152° upon introducing XSL surface structure to the AMS-based epoxy composites. Based on the standard electrochemical anti-corrosion and anti-biofilm measurements, the superhydrophobic BEAMS3 composite was found to exhibit a remarkable anti-corrosion efficiency of ~99% and antimicrobial efficacy of 82% as compared to that of hydrophilic epoxy coatings.}, }
@article {pmid38931048, year = {2024}, author = {Oalđe Pavlović, M and Kolarević, S and Đorđević Aleksić, J and Vuković-Gačić, B}, title = {Exploring the Antibacterial Potential of Lamiaceae Plant Extracts: Inhibition of Bacterial Growth, Adhesion, Invasion, and Biofilm Formation and Degradation in Pseudomonas aeruginosa PAO1.}, journal = {Plants (Basel, Switzerland)}, volume = {13}, number = {12}, pages = {}, pmid = {38931048}, issn = {2223-7747}, support = {451-03-65/2024-03/200178//Ministry of Education, Science and Technological Development of the Republic of Serbia/ ; 451-03-66/2024-03/200178//Ministry of Education, Science and Technological Development of the Republic of Serbia/ ; 451-03-66/2024-03/200007//Ministry of Education, Science and Technological Development of the Republic of Serbia/ ; 451-03-66/2024-03/200053//Ministry of Education, Science and Technological Development of the Republic of Serbia/ ; }, abstract = {In response to the global rise in antibiotic resistance and the prevalence of bacterial biofilm-related infections, the antibacterial efficacy of methanolic, ethanolic, and aqueous extracts of 18 Lamiaceae plants from Serbia was evaluated. The total coumarins and triterpenes were detected spectrophotometrically, while a microdilution assay measured their effects on bacterial growth. Additionally, the impact of these extracts was assessed on Pseudomonas aeruginosa PAO1 adhesion and invasion in human fibroblasts and biofilm formation and degradation. The alcoholic extracts had the highest phytochemical content, with Teucrium montanum and Lavandula angustifolia being the richest in coumarins and triterpenes, respectively. Gram-positive bacteria, particularly Bacillus subtilis, were more susceptible to the extracts. Hyssopus officinalis ethanolic and Sideritis scardica methanolic extracts inhibited bacterial growth the most efficiently. Although the extracts did not inhibit bacterial adhesion, most ethanolic extracts significantly reduced bacterial invasion. Origanum vulgare and H. officinalis ethanolic extracts significantly inhibited biofilm formation, while Teucrium chamaedrys extract was the most active in biofilm degradation. This study significantly contributes to the literature by examining the antibacterial activity of Lamiaceae extracts, addressing major literature gaps, and underscoring their antibacterial potential, particularly Satureja montana and O. vulgare ethanolic extracts, linking their efficacy to coumarins and triterpenes.}, }
@article {pmid38930580, year = {2024}, author = {Mikziński, P and Kraus, K and Widelski, J and Paluch, E}, title = {Modern Microbiological Methods to Detect Biofilm Formation in Orthopedy and Suggestions for Antibiotic Therapy, with Particular Emphasis on Prosthetic Joint Infection (PJI).}, journal = {Microorganisms}, volume = {12}, number = {6}, pages = {}, pmid = {38930580}, issn = {2076-2607}, abstract = {Biofilm formation is a serious problem that relatively often causes complications in orthopedic surgery. Biofilm-forming pathogens invade implanted foreign bodies and surrounding tissues. Such a condition, if not limited at the appropriate time, often requires reoperation. This can be partially prevented by selecting an appropriate prosthesis material that prevents the development of biofilm. There are many modern techniques available to detect the formed biofilm. By applying them we can identify and visualize biofilm-forming microorganisms. The most common etiological factors associated with biofilms in orthopedics are: Staphylococcus aureus, coagulase-negative Staphylococci (CoNS), and Enterococcus spp., whereas Gram-negative bacilli and Candida spp. also deserve attention. It seems crucial, for therapeutic success, to eradicate the microorganisms able to form biofilm after the implantation of endoprostheses. Planning the effective targeted antimicrobial treatment of postoperative infections requires accurate identification of the microorganism responsible for the complications of the procedure. The modern microbiological testing techniques described in this article show the diagnostic options that can be followed to enable the implementation of effective treatment.}, }
@article {pmid38930479, year = {2024}, author = {Liu, D and Liu, J and Ran, L and Yang, Z and He, Y and Yang, H and Yu, Y and Fu, L and Zhu, M and Chen, H}, title = {Oleanolic Acid Promotes the Formation of Probiotic Escherichia coli Nissle 1917 (EcN) Biofilm by Inhibiting Bacterial Motility.}, journal = {Microorganisms}, volume = {12}, number = {6}, pages = {}, pmid = {38930479}, issn = {2076-2607}, support = {NCTIP-XD/B12, NCTIP-XD/C17; CSTB2023TIAD-LDX0006;2022LYXZ030; SWU-KQ22045//National Center of Technology Innovation for Pigs; Chongqing Technical Innovation and Application Development Special General Project;the Project of Shandong Province on the Transformation of Scientific and Technological Achievements;Fundamental Research/ ; }, abstract = {Probiotic biofilms have been beneficial in the fight against infections, restoring the equilibrium of the host's gut microbiota, and enhancing host health. They are considered a novel strategy for probiotic gut colonization. In this case, we evaluated the effects of various active substances from traditional Chinese medicine on Escherichia coli Nissle 1917 (EcN) to determine if they promote biofilm formation. It was shown that 8-64 μg/mL of oleanolic acid increased the development of EcN biofilm. Additionally, we observed that oleanolic acid can effectively suppress biofilm formation in pathogenic bacteria such as Salmonella and Staphylococcus aureus. Next, we assessed the amount of EcN extracellular polysaccharides, the number of live bacteria, their metabolic activity, the hydrophobicity of their surface, and the shape of their biofilms using laser confocal microscopy. Through transcriptome analysis, a total of 349 differentially expressed genes were identified, comprising 134 upregulated and 215 downregulated genes. GO functional enrichment analysis and KEGG pathway enrichment analysis revealed that oleanolic acid functions are through the regulation of bacterial motility, the iron absorption system, the two-component system, and adhesion pathways. These findings suggest that the main effects of oleanolic acid are to prevent bacterial motility, increase initial adhesion, and encourage the development of EcN biofilms. In addition, oleanolic acid interacts with iron absorption to cooperatively control the production of EcN biofilms within an optimal concentration range. Taking these results together, this study suggests that oleanolic acid may enhance probiotic biofilm formation in the intestines, presenting new avenues for probiotic product development.}, }
@article {pmid38929094, year = {2024}, author = {Kim, JH and Dong, J and Le, BH and Lonergan, ZR and Gu, W and Girke, T and Zhang, W and Newman, DK and Martins-Green, M}, title = {Pseudomonas aeruginosa Activates Quorum Sensing, Antioxidant Enzymes and Type VI Secretion in Response to Oxidative Stress to Initiate Biofilm Formation and Wound Chronicity.}, journal = {Antioxidants (Basel, Switzerland)}, volume = {13}, number = {6}, pages = {}, pmid = {38929094}, issn = {2076-3921}, support = {1 R21 AI156688-01/GF/NIH HHS/United States ; }, abstract = {Pseudomonas aeruginosa (PA) is an opportunistic pathogen frequently isolated from cutaneous chronic wounds. How PA, in the presence of oxidative stress (OS), colonizes chronic wounds and forms a biofilm is still unknown. The purpose of this study is to investigate the changes in gene expression seen when PA is challenged with the high levels of OS present in chronic wounds. We used a biofilm-forming PA strain isolated from the chronic wounds of our murine model (RPA) and performed a qPCR to obtain gene expression patterns as RPA developed a biofilm in vitro in the presence of high levels of OS, and then compared the findings in vivo, in our mouse model of chronic wounds. We found that the planktonic bacteria under OS conditions overexpressed quorum sensing genes that are important for the bacteria to communicate with each other, antioxidant stress genes important to reduce OS in the microenvironment for survival, biofilm formation genes and virulence genes. Additionally, we performed RNAseq in vivo and identified the activation of novel genes/pathways of the Type VI Secretion System (T6SS) involved in RPA pathogenicity. In conclusion, RPA appears to survive the high OS microenvironment in chronic wounds and colonizes these wounds by turning on virulence, biofilm-forming and survival genes. These findings reveal pathways that may be promising targets for new therapies aimed at disrupting PA-containing biofilms immediately after debridement to facilitate the treatment of chronic human wounds.}, }
@article {pmid38928770, year = {2024}, author = {Sung, K and Park, M and Chon, J and Kweon, O and Paredes, A and Khan, SA}, title = {Chicken Juice Enhances C. jejuni NCTC 11168 Biofilm Formation with Distinct Morphological Features and Altered Protein Expression.}, journal = {Foods (Basel, Switzerland)}, volume = {13}, number = {12}, pages = {}, pmid = {38928770}, issn = {2304-8158}, support = {E0735601//United States Food and Drug Administration/ ; }, abstract = {Campylobacter jejuni is the foodborne pathogen causing most gastrointestinal infections. Understanding its ability to form biofilms is crucial for devising effective control strategies in food processing environments. In this study, we investigated the growth dynamics and biofilm formation of C. jejuni NCTC 11168 in various culture media, including chicken juice (CJ), brain heart infusion (BHI), and Mueller Hinton (MH) broth. Our results demonstrated that C. jejuni exhibited a higher growth rate and enhanced biofilm formation in CJ and in 1:1 mixtures of CJ with BHI or MH broth compared to these measures in BHI or MH broth alone. Electron microscopy unveiled distinct morphological attributes of late-stage biofilm cells in CJ, including the presence of elongated spiral-shaped cells, thinner stretched structures compared to regular cells, and extended thread-like structures within the biofilms. Proteomic analysis identified significant alterations in protein expression profiles in C. jejuni biofilms, with a predominance of downregulated proteins associated with vital functions like metabolism, energy production, and amino acid and protein biosynthesis. Additionally, a significant proportion of proteins linked to biofilm formation, virulence, and iron uptake were suppressed. This shift toward a predominantly coccoid morphology echoed the reduced energy demands of these biofilm communities. Our study unlocks valuable insights into C. jejuni's biofilm in CJ, demonstrating its adaptation and survival.}, }
@article {pmid38927396, year = {2024}, author = {Macedo, TT and Malavazi, LM and Vargas, GQ and Gonçalves, FJDS and Gomes, APAP and Bueno, MR and Aguiar da Silva, LD and Figueiredo, LC and Bueno-Silva, B}, title = {Combination of Neovestitol and Vestitol Modifies the Profile of Periodontitis-Related Subgingival Multispecies Biofilm.}, journal = {Biomedicines}, volume = {12}, number = {6}, pages = {}, pmid = {38927396}, issn = {2227-9059}, support = {#2019/19691-0; # 2017/16377-7//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado de S&#xe3;o Paulo/ ; # 428984/2018-5//National Council for Scientific and Technological Development/ ; n/a//Coordena&#xe7;&#xe3;o de Aperfeicoamento de Pessoal de N&#xed;vel Superior/ ; #3364/23 and #2878/23//Fund to support teaching, research and extension (FAEPEX - Unicamp)/ ; n/a//Latin American Oral Health Association/ ; }, abstract = {The aim of this study was to evaluate the effect of the combination of neovestitol-vestitol (CNV) compounds obtained from Brazilian red propolis on the microbiological profile of a mature multispecies subgingival biofilm. The biofilm with 32 bacterial species associated with periodontitis was formed for seven days using a Calgary device. Treatment with CNV (1600, 800, 400, and 200 μg/mL), amoxicillin (54 μg/mL), and vehicle control was performed for 24 h on the last day of biofilm formation. Biofilm metabolic activity and DNA-DNA hybridization (checkerboard) assays were performed. The groups treated with CNV 1600 and amoxicillin reduced 25 and 13 species, respectively, compared to the control vehicle treatment (p ≤ 0.05); both reduced P. gingivalis, while only CNV reduced T. forsythia. When the data from the two treatments (CNV and AMOXI) were compared, a statistically significant difference was observed in 13 species, particularly members of Socransky's orange complex. Our results showed that CNV at 1600 μg/mL showed the best results regarding the metabolic activity of mature biofilms and obtained a reduction in species associated with the disease, such as T. forsythia, showing a better reduction than amoxicillin. Therefore, CNV seems to be a promising alternative to eradicate biofilms and reduce their pathogenicity.}, }
@article {pmid38927237, year = {2024}, author = {Iniesta, M and Vasconcelos, V and Sanz, M and Herrera, D}, title = {Supra- and Subgingival Microbiome in Gingivitis and Impact of Biofilm Control: A Comprehensive Review.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {6}, pages = {}, pmid = {38927237}, issn = {2079-6382}, abstract = {This comprehensive review aimed (1) to characterize the sub- and supragingival microbiome in patients with biofilm-induced gingivitis (including experimental gingivitis), (2) to assess its stability and evolution over time, and (3) to assess the impact of biofilm control measures on this stability. An electronic search of the MEDLINE[®]/PubMed[®] database until December 2023 was conducted. NCBI Taxonomy, eHOMD 16S rRNA Reference Sequence, and Tree Version 15.23 databases were used to standardize taxonomic nomenclature. Out of 89 papers initially retrieved, 14 studies were finally included: 11 using experimental gingivitis as a model and three randomized clinical trials evaluating the impact of biofilm control measures. Among them, five characterized the subgingival microbiome, nine the supragingival microbiome, and one both the sub- and supragingival microbiome. In addition, five studies evaluated the effect of toothpaste, and four studies evaluated the effect of mouth rinses. The diversity and structure of the microbiome differed significantly between patients with periodontal health and those with biofilm-induced gingivitis (including experimental gingivitis). Those differences were not reversed through conventional oral hygiene measures. Specific antiseptic agents, especially if delivered as mouth rinses, may have an impact on the supra- and subgingival microbiome in gingivitis.}, }
@article {pmid38927205, year = {2024}, author = {Flores-Vargas, G and Bergsveinson, J and Korber, DR}, title = {Environmentally Relevant Antibiotic Concentrations Exert Stronger Selection Pressure on River Biofilm Resistomes than AMR-Reservoir Effluents.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {6}, pages = {}, pmid = {38927205}, issn = {2079-6382}, abstract = {Freshwater environments are primary receiving systems of wastewater and effluents, which carry low concentrations of antibiotics and antimicrobial-resistant (AMR) bacteria and genes. Aquatic microbial communities are thus exposed to environmentally relevant concentrations of antibiotics (ERCA) that presumably influence the acquisition and spread of environmental AMR. Here, we analyzed ERCA exposure with and without the additional presence of municipal wastewater treatment plant effluent (W) and swine manure run-off (M) on aquatic biofilm resistomes. Microscopic analyses revealed decreased taxonomic diversity and biofilm structural integrity, while metagenomic analysis revealed an increased abundance of resistance, virulence, and mobile element-related genes at the highest ERCA exposure levels, with less notable impacts observed when solely exposed to W or M effluents. Microbial function predictions indicated increased gene abundance associated with energy and cell membrane metabolism and heavy metal resistance under ERCA conditions. In silico predictions of increased resistance mechanisms did not correlate with observed phenotypic resistance patterns when whole communities were exposed to antimicrobial susceptibility testing. This reveals important insight into the complexity of whole-community coordination of physical and genetic responses to selective pressures. Lastly, the environmental AMR risk assessment of metagenomic data revealed a higher risk score for biofilms grown at sub-MIC antibiotic conditions.}, }
@article {pmid38927142, year = {2024}, author = {Offman, EM and Leestemaker-Palmer, A and Fathi, R and Keefe, B and Bibliowicz, A and Raday, G and Bermudez, LE}, title = {Triple-Antibiotic Combination Exerts Effective Activity against Mycobacterium avium subsp. hominissuis Biofilm and Airway Infection in an In Vivo Murine Model.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {6}, pages = {}, pmid = {38927142}, issn = {2079-6382}, support = {001//RedHill Biofarma/ ; }, abstract = {OBJECTIVES: Slow-growing nontuberculous mycobacteria (NTMs) are highly prevalent and routinely cause opportunistic intracellular infectious disease in immunocompromised hosts.<br><br>METHODS: The activity of the triple combination of antibiotics, clarithromycin (CLR), rifabutin (RFB), and clofazimine (CFZ), was evaluated and compared with the activity of single antibiotics as well as with double combinations in an in vitro biofilm assay and an in vivo murine model of Mycobacterium avium subsp. hominissuis (M. avium) lung infection.<br><br>RESULTS: Treatment of 1-week-old biofilms with the triple combination exerted the strongest effect of all (0.12 &#xb1; 0.5 &#xd7; 10[7] CFU/mL) in reducing bacterial growth as compared to the untreated (5.20 &#xb1; 0.5 &#xd7; 10[7]/mL) or any other combination (&#x2265;0.75 &#xb1; 0.6 &#xd7; 10[7]/mL) by 7 days. The treatment of mice intranasally infected with M. avium with either CLR and CFZ or the triple combination provided the greatest reduction in CLR-sensitive M. avium bacterial counts in both the lung and spleen compared to any single antibiotic or remaining double combination by 4 weeks posttreatment. After 4 weeks of treatment with the triple combination, there were no resistant colonies detected in mice infected with a CLR-resistant strain. No clear relationships between treatment and spleen or lung organ weights were apparent after triple combination treatment.<br><br>CONCLUSIONS: The biofilm assay data and mouse disease model efficacy results support the further investigation of the triple-antibiotic combination.}, }
@article {pmid38925646, year = {2024}, author = {De Padua, JC and Tanaka, T and Ueno, K and Dela Cruz, TEE and Ishihara, A}, title = {Isolation of 2,2'-azoxybisbenzyl alcohol from Agaricus subrutilescens and its inhibitory activity against bacterial biofilm formation.}, journal = {Bioscience, biotechnology, and biochemistry}, volume = {88}, number = {9}, pages = {983-991}, doi = {10.1093/bbb/zbae089}, pmid = {38925646}, issn = {1347-6947}, support = {//Department of Science &amp; Technology/ ; }, mesh = {*Biofilms/drug effects ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology/chemistry/isolation &amp; purification ; *Agaricus/chemistry ; Quorum Sensing/drug effects ; }, abstract = {Virulence pathways in pathogenic bacteria are regulated by quorum sensing mechanisms, particularly biofilm formation through autoinducer (AI) production and sensing. In this study, the culture filtrate extracted from an edible mushroom, Agaricus subrutilescens, was fractionated to isolate a compound that inhibits biofilm formation. Four gram-negative bacteria (Klebsiella pneumoniae, Escherichia coli, Proteus mirabilis, and Enterobacter cloacae) and two gram-positive bacteria (Enterococcus faecalis and Staphylococcus aureus) were used for the bioassay. The bioassay-guided chromatographic separations of the culture filtrate extract resulted in the isolation of the compound. Further, spectroscopic analyses revealed the identity of the compound as 2,2'-azoxybisbenzyl alcohol (ABA). The minimum inhibitory and sub-inhibitory concentrations of the compound were also determined. Azoxybisbenzyl alcohol was significantly effective in inhibiting biofilm formation in all tested bacteria, with half-maximal inhibitory concentrations of 3-11 µg/mL. Additionally, the bioactivity of ABA was confirmed through the bioassays for the inhibition of exopolysaccharide matrixes and AI activities.}, }
@article {pmid38925344, year = {2024}, author = {Alhariry, J and Kumar, A and Yadav, TC and Yadav, E and Prasad, R and Poluri, KM and Gupta, P}, title = {Tyrosol-gold nanoparticle functionalized acacia gum-PVA nanofibers for mitigation of Candida biofilm.}, journal = {Microbial pathogenesis}, volume = {193}, number = {}, pages = {106763}, doi = {10.1016/j.micpath.2024.106763}, pmid = {38925344}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Gold/chemistry/pharmacology ; *Nanofibers/chemistry ; *Phenylethyl Alcohol/analogs &amp; derivatives/pharmacology/chemistry ; *Metal Nanoparticles/chemistry ; *Antifungal Agents/pharmacology ; *Candida/drug effects ; *Gum Arabic/chemistry/pharmacology ; Chitosan/chemistry/pharmacology ; Nanocomposites/chemistry ; Microbial Sensitivity Tests ; Polyvinyl Alcohol/chemistry ; Drug Liberation ; Silver/pharmacology/chemistry ; Ergosterol/chemistry ; Hydrophobic and Hydrophilic Interactions ; }, abstract = {Increasing incidences of fungal infections and prevailing antifungal resistance in healthcare settings has given rise to an antifungal crisis on a global scale. The members of the genus Candida, owing to their ability to acquire sessile growth, are primarily associated with superficial to invasive fungal infections, including the implant-associated infections. The present study introduces a novel approach to combat the sessile/biofilm growth of Candida by fabricating nanofibers using a nanoencapsulation approach. This technique involves the synthesis of tyrosol (TYS) functionalized chitosan gold nanocomposite, which is then encapsulated into PVA/AG polymeric matrix using electrospinning. The FESEM, FTIR analysis of prepared TYS-AuNP@PVA/AG NF suggested the successful encapsulation of TYS into the nanofibers. Further, the sustained and long-term stability of TYS in the medium was confirmed by drug release and storage stability studies. The prepared nanomats can absorb the fluid, as evidenced by the swelling index of the nanofibers. The growth and biofilm inhibition, as well as the disintegration studies against Candida, showed 60-70 % biofilm disintegration when 10 mg of TYS-AuNP@PVA/AG NF was used, hence confirming its biological effectiveness. Subsequently, the nanofibers considerably reduced the hydrophobicity index and ergosterol content of the treated cells. Considering the challenges associated with the inhibition/disruption of fungal biofilm, the fabricated nanofibers prove their effectiveness against Candida biofilm. Therefore, nanocomposite-loaded nanofibers have emerged as potential materials that can control fungal colonization and could also promote healing.}, }
@article {pmid38924949, year = {2024}, author = {Wang, L and Zhang, C and Kang, X and Liu, Y and Qiu, Y and Wanyan, D and Liu, J and Cheng, G and Huang, X}, title = {Establishing mainstream partial nitrification in the membrane aerated biofilm reactor by limiting the oxygen concentration in the biofilm.}, journal = {Water research}, volume = {261}, number = {}, pages = {121984}, doi = {10.1016/j.watres.2024.121984}, pmid = {38924949}, issn = {1879-2448}, mesh = {*Biofilms ; *Bioreactors ; *Nitrification ; *Oxygen/metabolism ; Waste Disposal, Fluid/methods ; Nitrogen/metabolism ; Membranes, Artificial ; Wastewater/chemistry ; }, abstract = {The proliferation of nitrite oxidizing bacteria (NOB) still remains as a major challenge for nitrogen removal in mainstream wastewater treatment process based on partial nitrification (PN). This study investigated different operational conditions to establish mainstream PN for the fast start-up of membrane aerated biofilm reactor (MABR) systems. Different oxygen controlling strategies were adopted by employing different influent NH4[+]-N loads and oxygen supply strategies to inhibit NOB. We indicated the essential for NOB suppression was to reduce the oxygen concentration of the inner biofilm and the thickness of aerobic biofilm. A higher NH4[+]-N load (7.4 g-N/(m[2]·d)) induced higher oxygen utilization rate (14.4 g-O2/(m[2]·d)) and steeper gradient of oxygen concentration, which reduced the thickness of aerobic biofilm. Employing closed-end oxygen supply mode exhibited the minimum concentration of oxygen to realize PN, which was over 46% reduction of the normal open-end oxygen mode. Under the conditions of high NH4[+]-N load and closed-end oxygen supply mode, the microbial community exhibited a comparative advantage of ammonium oxidizing bacteria over NOB in the aerobic biofilm, with a relative abundance of Nitrosomonas of 30-40% and no detection of Nitrospira. The optimal fast start-up strategy was proposed with open-end aeration mode in the first 10 days and closed-end mode subsequently under high NH4[+]-N load. The results revealed the mechanism of NOB inhibition on the biofilm and provided strategies for a quick start-up and stable mainstream PN simultaneously, which poses great significance for the future application of MABR.}, }
@article {pmid38924874, year = {2024}, author = {Santana, JS and Delbem, ACB and Pessan, JP and Sampaio, C and de Morais, LA and Pereira, TL and Monteiro, DR and Hosida, TY}, title = {Dual-species biofilm of Streptococcus mutans and Candida albicans produces subsurface caries lesions on bovine enamel.}, journal = {Archives of oral biology}, volume = {166}, number = {}, pages = {106029}, doi = {10.1016/j.archoralbio.2024.106029}, pmid = {38924874}, issn = {1879-1506}, mesh = {*Biofilms ; *Candida albicans/physiology ; *Streptococcus mutans/physiology ; *Dental Caries/microbiology ; Animals ; Cattle ; Polysaccharides, Bacterial/metabolism ; Sucrose/pharmacology ; Fluorides/pharmacology ; *Dental Enamel/chemistry/microbiology/pathology ; Models, Animal ; }, abstract = {OBJECTIVES: To develop a protocol for forming subsurface caries lesions on bovine enamel by dual-species biofilms of Streptococcus mutans and Candida albicans in vitro.<br><br>DESIGN: Biofilms were grown on bovine enamel specimens in artificial saliva (AS) for seven days. After 24&#xa0;h of formation, the AS was supplemented or not with fluoride (F) using sodium fluoride (0.005 or 0.008&#xa0;ppm&#xa0;F), and the biofilms were exposed or not to a 20&#xa0;% sucrose solution (reproducing a cariogenic challenge) once/day. On the seventh day, the biofilms were harvested and had their extracellular polysaccharides (EPS) and inorganic components analyzed. The specimens were subjected to computed X-ray microtomography analysis to determine their mineral concentration. Data were compared using two-way analyses of variance, followed by Fisher's LSD or Student-Newman-Keuls tests (p&#xa0;<&#xa0;0.05).<br><br>RESULTS: Biofilms exposed to the cariogenic challenge had significantly higher EPS concentrations than those not exposed, regardless of the presence of F. For biofilms grown with 0.008&#xa0;ppm&#xa0;F, those exposed to the cariogenic challenge had lower F levels than those not exposed. For biofilms exposed to the cariogenic challenge, those grown with 0.008&#xa0;ppm&#xa0;F had lower lesion depths and integrated mineral loss, and higher outer layers than those grown without F.<br><br>CONCLUSIONS: The dual biofilm model assessed was able to create subsurface caries lesions in bovine enamel in vitro, which was influenced by the presence of F in the culture medium and exposure to sucrose.}, }
@article {pmid38924372, year = {2024}, author = {Ballesté, E and Liang, H and Migliorato, L and Sala-Comorera, L and Méndez, J and Garcia-Aljaro, C}, title = {Exploring plastic biofilm formation and Escherichia coli colonisation in marine environments.}, journal = {Environmental microbiology reports}, volume = {16}, number = {3}, pages = {e13308}, pmid = {38924372}, issn = {1758-2229}, support = {PID2019-108957GA-I00//Ministerio de Ciencia e Innovaci&#xf3;n/ ; }, mesh = {*Biofilms/growth &amp; development ; *Escherichia coli/genetics/physiology/isolation &amp; purification/growth &amp; development ; *Plastics ; *Seawater/microbiology ; RNA, Ribosomal, 16S/genetics ; Water Microbiology ; }, abstract = {Microorganisms, including potential pathogens, can colonise plastic surfaces in aquatic environments. This study investigates the colonisation of plastic pellets by Escherichia coli (E. coli) as a proxy for faecal pathogens in aquatic environments. Plastic pellets from a polluted beach were placed in seawater aquaria spiked with E. coli. Diverse bacteria, primarily from the Proteobacteria phylum, rapidly colonised the pellets within 24 h, with notable species known for plastic or hydrocarbon degradation. Over 26 days, biofilms formed on the plastic surfaces, reaching bacterial populations of up to 6.8·10[5] gene copies (gc) of the 16S rRNA mm[-2]. E. coli, was detected in the pellets for up to 7 days using culture methods, exhibiting varying attachment densities regardless of source or environmental factors. The study highlights plastic biofilms as reservoirs for E. coli, contributing to the survival and persistence of faecal bacteria in aquatic systems. These findings deepen our understanding of the risks associated with plastic pollution in marine settings, offering insights into the behaviour of faecal indicators and their implications for water quality assessments, while providing valuable information on potential pathogen dissemination within plastic-associated microbial communities.}, }
@article {pmid38924307, year = {2024}, author = {Liu, JD and Van Treeck, KE and Marston, WA and Papadopoulou, V and Rowe, SE}, title = {Ultrasound-Mediated Antibiotic Delivery to In Vivo Biofilm Infections: A Review.}, journal = {Chembiochem : a European journal of chemical biology}, volume = {25}, number = {20}, pages = {e202400181}, pmid = {38924307}, issn = {1439-7633}, support = {R01 AI167978/AI/NIAID NIH HHS/United States ; R01AI167978/GF/NIH HHS/United States ; }, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/chemistry/pharmacology ; Humans ; *Drug Delivery Systems ; *Ultrasonic Waves ; Animals ; Bacterial Infections/drug therapy ; }, abstract = {Bacterial biofilms are a significant concern in various medical contexts due to their resilience to our immune system as well as antibiotic therapy. Biofilms often require surgical removal and frequently lead to recurrent or chronic infections. Therefore, there is an urgent need for improved strategies to treat biofilm infections. Ultrasound-mediated drug delivery is a technique that combines ultrasound application, often with the administration of acoustically-active agents, to enhance drug delivery to specific target tissues or cells within the body. This method involves using ultrasound waves to assist in the transportation or activation of medications, improving their penetration, distribution, and efficacy at the desired site. The advantages of ultrasound-mediated drug delivery include targeted and localized delivery, reduced systemic side effects, and improved efficacy of the drug at lower doses. This review scrutinizes recent advances in the application of ultrasound-mediated drug delivery for treating biofilm infections, focusing on in vivo studies. We examine the strengths and limitations of this technology in the context of wound infections, device-associated infections, lung infections and abscesses, and discuss current gaps in knowledge and clinical translation considerations.}, }
@article {pmid38923398, year = {2024}, author = {Nouraei, H and Zare, S and Nemati, M and Amirzadeh, N and Motamedi, M and Shabanzadeh, S and Zomorodian, K and Pakshir, K}, title = {Comparative analysis of enzymatic profiles and biofilm formation in clinical and environmental Candida kefyr isolates.}, journal = {Environmental microbiology reports}, volume = {16}, number = {3}, pages = {e13282}, pmid = {38923398}, issn = {1758-2229}, support = {26387//Vice-Chancellor for Research, Shiraz University of Medical Sciences/ ; 26828//Vice-Chancellor for Research, Shiraz University of Medical Sciences/ ; }, mesh = {*Biofilms/growth &amp; development ; *Candida/isolation &amp; purification/enzymology/physiology/classification ; Humans ; *Candidiasis/microbiology ; *Phospholipases/metabolism ; Esterases/metabolism ; Hemolysin Proteins/metabolism ; Peptide Hydrolases/metabolism ; Environmental Microbiology ; }, abstract = {The global landscape of Candida infections has seen a significant shift. Previously, Candida albicans was the predominant species. However, there has been an emergence of non-albicans Candida species, which are often less susceptible to antifungal treatment. Candida kefyr, in particular, has been increasingly associated with infections. This study aimed to investigate the profiles of enzymatic activity and biofilm formation in both clinical and non-clinical isolates of C. kefyr. A total of 66 C. kefyr isolates were analysed. The activities of proteinase and phospholipase were assessed using bovine serum albumin and egg yolk agar, respectively. Haemolysin, caseinolytic and esterase activities were evaluated using specific methods. Biofilm formation was investigated using crystal violet staining. The findings indicated that biofilm and proteinase activity were detected in 81.8% and 93.9% of all the isolates, respectively. Haemolysin activity was observed with the highest occurrence (95.5%) among normal microbiota isolates. Esterase activity was predominantly identified in dairy samples and was absent in hospital samples. Caseinase production was found with the highest occurrence (18.2%) in normal microbiota and hospital samples. Phospholipase activity was limited, found in only 3% of all the isolates. These findings reveal variations in enzyme activity between clinical and non-clinical C. kefyr isolates. This sheds light on their pathogenic potential and has implications for therapeutic strategies.}, }
@article {pmid38922976, year = {2024}, author = {Bell, RD and Cann, EA and Mishra, B and Valencia, M and Zhang, Q and Huang, M and Yang, X and Carli, A and Bostrom, M and Ivashkiv, LB}, title = {Staphyloccocus aureus biofilm, in absence of planktonic bacteria, produces factors that activate counterbalancing inflammatory and immune-suppressive genes in human monocytes.}, journal = {Journal of orthopaedic research : official publication of the Orthopaedic Research Society}, volume = {42}, number = {11}, pages = {2582-2592}, pmid = {38922976}, issn = {1554-527X}, support = {R01 AI046712/AI/NIAID NIH HHS/United States ; R01AI046712//National Institute of Allergy and Infectious Diseases/ ; T32 AR071302-07/AR/NIAMS NIH HHS/United States ; T32 AR071302/AR/NIAMS NIH HHS/United States ; R01 AR050401/AR/NIAMS NIH HHS/United States ; R01DE019420-14/DE/NIDCR NIH HHS/United States ; R01 DE019420/DE/NIDCR NIH HHS/United States ; }, mesh = {*Biofilms ; Humans ; *Staphylococcus aureus/physiology ; *Monocytes/immunology/metabolism ; }, abstract = {Staphyloccocus aureus (S. aureus) is a major bacterial pathogen in orthopedic periprosthetic joint infection (PJI). S. aureus forms biofilms that promote persistent infection by shielding bacteria from immune cells and inducing an antibiotic-tolerant metabolic state. We developed an in vitro system to study S. aureus biofilm interactions with primary human monocytes in the absence of planktonic bacteria. In line with previous in vivo data, S. aureus biofilm induced expression of inflammatory genes such as TNF and IL1B, and their anti-inflammatory counter-regulator IL10. S. aureus biofilm also activated expression of PD-1 ligands, and IL-1RA, molecules that have the potential to suppress T cell function or differentiation of protective Th17 cells. Gene induction did not require monocyte:biofilm contact and was mediated by a soluble factor(s) produced by biofilm-encased bacteria that was heat resistant and >3 kD in size. Activation of suppressive genes by biofilm was sensitive to suppression by Jak kinase inhibition. These results support an evolving paradigm that biofilm plays an active role in modulating immune responses, and suggest this occurs via production of a soluble vita-pathogen-associated molecular pattern, a molecule that signals microbial viability. Induction of T cell suppressive genes by S. aureus biofilm provides insights into mechanisms that can suppress T cell immunity in PJI.}, }
@article {pmid38922753, year = {2024}, author = {Rosazza, T and Earl, C and Eigentler, L and Davidson, FA and Stanley-Wall, NR}, title = {Reciprocal sharing of extracellular proteases and extracellular matrix molecules facilitates Bacillus subtilis biofilm formation.}, journal = {Molecular microbiology}, volume = {122}, number = {2}, pages = {184-200}, doi = {10.1111/mmi.15288}, pmid = {38922753}, issn = {1365-2958}, support = {097818/Z/11/WT_/Wellcome Trust/United Kingdom ; 102132/B/13/Z/WT_/Wellcome Trust/United Kingdom ; BB/P001335/1/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom ; BB/R012415/1/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom ; }, mesh = {*Biofilms/growth &amp; development ; *Bacillus subtilis/genetics/physiology/metabolism ; *Bacterial Proteins/metabolism/genetics ; *Extracellular Matrix/metabolism ; *Peptide Hydrolases/metabolism/genetics ; Nitrogen/metabolism ; Hydrophobic and Hydrophilic Interactions ; Glutamic Acid/metabolism ; Membrane Transport Proteins ; }, abstract = {Extracellular proteases are a class of public good that support growth of Bacillus subtilis when nutrients are in a polymeric form. Bacillus subtilis biofilm matrix molecules are another class of public good that are needed for biofilm formation and are prone to exploitation. In this study, we investigated the role of extracellular proteases in B. subtilis biofilm formation and explored interactions between different public good producer strains across various conditions. We confirmed that extracellular proteases support biofilm formation even when glutamic acid provides a freely available nitrogen source. Removal of AprE from the NCIB 3610 secretome adversely affects colony biofilm architecture, while sole induction of WprA activity into an otherwise extracellular protease-free strain is sufficient to promote wrinkle development within the colony biofilm. We found that changing the nutrient source used to support growth affected B. subtilis biofilm structure, hydrophobicity and architecture. We propose that the different phenotypes observed may be due to increased protease dependency for growth when a polymorphic protein presents the sole nitrogen source. We however cannot exclude that the phenotypic changes are due to alternative matrix molecules being made. Co-culture of biofilm matrix and extracellular protease mutants can rescue biofilm structure, yet reliance on extracellular proteases for growth influences population coexistence dynamics. Our findings highlight the intricate interplay between these two classes of public goods, providing insights into microbial social dynamics during biofilm formation across different ecological niches.}, }
@article {pmid38922407, year = {2024}, author = {Jayaraman, S and Rajendhran, N and Kannan, MA and Ramasamy, T}, title = {Quercetin disrupts biofilm formation and attenuates virulence of Aeromonas hydrophila.}, journal = {Archives of microbiology}, volume = {206}, number = {7}, pages = {326}, pmid = {38922407}, issn = {1432-072X}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Aeromonas hydrophila/drug effects/pathogenicity/physiology/growth &amp; development ; *Quercetin/pharmacology ; *Anti-Bacterial Agents/pharmacology ; *Molecular Docking Simulation ; Virulence/drug effects ; Microbial Sensitivity Tests ; Hemolysis/drug effects ; Bacterial Proteins/metabolism/genetics ; Virulence Factors/metabolism ; Animals ; }, abstract = {Aeromonas hydrophila poses significant health and economic challenges in aquaculture owing to its pathogenicity and prevalence. Overuse of antibiotics has led to multidrug resistance and environmental pollution, necessitating alternative strategies. This study investigated the antibacterial and antibiofilm potentials of quercetin against A. hydrophila. Efficacy was assessed using various assays, including antibacterial activity, biofilm inhibition, specific growth time, hemolysis inhibition, autoaggregation, and microscopic evaluation. Additionally, docking analysis was performed to explore potential interactions between quercetin and virulence proteins of A. hydrophila, including proaerolysin, chaperone needle-subunit complex of the type III secretion system, and alpha-pore forming toxin (PDB ID: 1PRE, 2Q1K, 6GRK). Quercetin exhibited potent antibacterial activity with 21.1 ± 1.1 mm zone of inhibition at 1.5 mg mL[-1]. It also demonstrated significant antibiofilm activity, reducing biofilm formation by 46.3 ± 1.3% at the MIC and attenuating autoaggregation by 55.9 ± 1.5%. Hemolysis was inhibited by 41 ± 1.8%. Microscopic analysis revealed the disintegration of the A. hydrophila biofilm matrix. Docking studies indicated active hydrogen bond interactions between quercetin and the targeted virulence proteins with the binding energy -3.2, -5.6, and -5.1 kcal mol[-]1, respectively. These results suggest that quercetin is an excellent alternative to antibiotics for combating A. hydrophila infection in aquaculture. The multifaceted efficacy of quercetin in inhibiting bacterial growth, biofilm formation, virulence factors, and autoaggregation highlights the potential for aquaculture health and sustainability. Future research should delve into the precise mechanisms of action and explore synergistic combinations with other compounds for enhanced efficacy and targeted interventions.}, }
@article {pmid38922241, year = {2024}, author = {Araujo, EMDS and Vidal, CMP and Zhu, M and Banas, JA and Freitas, AZ and Wetter, NU and Matos, AB}, title = {Comparison of biofilm models for producing artificial active white spot lesions.}, journal = {Journal of applied oral science : revista FOB}, volume = {32}, number = {}, pages = {e20230458}, pmid = {38922241}, issn = {1678-7765}, mesh = {*Biofilms ; Humans ; *Streptococcus mutans/physiology ; *Dental Caries/microbiology/therapy ; *Dental Enamel/microbiology/chemistry ; *Lacticaseibacillus casei/physiology ; Time Factors ; Reproducibility of Results ; Streptococcus sobrinus/physiology ; Spectrum Analysis, Raman ; Analysis of Variance ; Microscopy, Polarization ; Statistics, Nonparametric ; Tooth Remineralization/methods ; Reference Values ; Saliva/microbiology/chemistry ; Tooth Demineralization/microbiology ; Fluorescence ; }, abstract = {OBJECTIVE: This study compared three protocols for developing artificial white spot lesions (WSL) using biofilm models.<br><br>METHODOLOGY: In total, 45 human enamel specimens were sterilized and allocated into three groups based on the biofilm model: Streptococcus sobrinus and Lactobacillus casei (Ss+Lc), Streptococcus sobrinus (Ss), or Streptococcus mutans (Sm). Specimens were incubated in filter-sterilized human saliva to form the acquired pellicle and then subjected to the biofilm challenge consisting of three days of incubation with bacteria (for demineralization) and one day of remineralization, which was performed once for Ss+Lc (four days total), four times for Ss (16 days total), and three times for Sm (12 days total). After WSL creation, the lesion fluorescence, depth, and chemical composition were assessed using Quantitative Light-induced Fluorescence (QLF), Polarized Light Microscopy (PLM), and Raman Spectroscopy, respectively. Statistical analysis consisted of two-way ANOVA followed by Tukey's post hoc test (&#x3b1;=0.05). WSL created using the Ss+Lc protocol presented statistically significant higher fluorescence loss (&#x394;F) and integrated fluorescence (&#x394;Q) in comparison to the other two protocols (p<0.001).<br><br>RESULTS: In addition, Ss+Lc resulted in significantly deeper WSL (137.5 &#xb5;m), followed by Ss (84.1 &#xb5;m) and Sm (54.9 &#xb5;m) (p<0.001). While high mineral content was observed in sound enamel surrounding the WSL, lesions created with the Ss+Lc protocol showed the highest demineralization level and changes in the mineral content among the three protocols.<br><br>CONCLUSION: The biofilm model using S. sobrinus and L. casei for four days was the most appropriate and simplified protocol for developing artificial active WSL with lower fluorescence, higher demineralization, and greater depth.}, }
@article {pmid38921816, year = {2024}, author = {Silva, V and Ribeiro, J and Teixeira, P and Pinto, P and Vieira-Pinto, M and Poeta, P and Caniça, M and Igrejas, G}, title = {Genetic Complexity of CC5 Staphylococcus aureus Isolates Associated with Sternal Bursitis in Chickens: Antimicrobial Resistance, Virulence, Plasmids, and Biofilm Formation.}, journal = {Pathogens (Basel, Switzerland)}, volume = {13}, number = {6}, pages = {}, pmid = {38921816}, issn = {2076-0817}, support = {UIDB/00772/2020 Doi:10.54499/UIDB/00772/2020//FCT/ ; UIDB/50006/2020 DOI 10.54499/UIDB/50006/2020//FCT/ ; }, abstract = {Sternal bursitis, a common inflammatory condition in poultry, poses significant challenges to both animal welfare and public health. This study aimed to investigate the prevalence, antimicrobial resistance, and genetic characteristics of Staphylococcus aureus isolates associated with sternal bursitis in chickens. Ninety-eight samples were collected from affected chickens, and 24 S. aureus isolates were identified. Antimicrobial susceptibility testing revealed resistance to multiple agents, with a notable prevalence of aminoglycoside resistance genes. Whole genome sequencing elucidated the genetic diversity and virulence profiles of the isolates, highlighting the predominance of clonal complex 5 (CC5) strains. Additionally, biofilm formation assays demonstrated moderate biofilm production capacity among the isolates. These findings underscore the importance of vigilant monitoring and targeted interventions to mitigate the impact of sternal bursitis in poultry production systems.}, }
@article {pmid38921377, year = {2024}, author = {Zhu, X and Jin, F and Yang, G and Zhuang, T and Zhang, C and Zhou, H and Niu, X and Wang, H and Wu, D}, title = {Mitochondrial Protease Oct1p Regulates Mitochondrial Homeostasis and Influences Pathogenicity through Affecting Hyphal Growth and Biofilm Formation Activities in Candida albicans.}, journal = {Journal of fungi (Basel, Switzerland)}, volume = {10}, number = {6}, pages = {}, pmid = {38921377}, issn = {2309-608X}, support = {823714322//National Natural Science Foundation of China/ ; }, abstract = {Mitochondria, as the core metabolic organelles, play a crucial role in aerobic respiration/biosynthesis in fungi. Numerous studies have demonstrated a close relationship between mitochondria and Candida albicans virulence and drug resistance. Here, we report an octapeptide-aminopeptidase located in the mitochondrial matrix named Oct1p. Its homolog in the model fungus Saccharomyces cerevisiae is one of the key proteins in maintaining mitochondrial respiration and protein stability. In this study, we utilized evolutionary tree analysis, gene knockout experiments, mitochondrial function detection, and other methods to demonstrate the impact of Oct1p on the mitochondrial function of C. albicans. Furthermore, through transcriptome analysis, real-time quantitative PCR, and morphological observation, we discovered that the absence of Oct1p results in functional abnormalities in C. albicans, affecting hyphal growth, cell adhesion, and biofilm formation. Finally, the in vivo results of the infection of Galleria mellonella larvae and vulvovaginal candidiasis in mice indicate that the loss of Oct1p led to the decreased virulence of C. albicans. In conclusion, this study provides a solid theoretical foundation for treating Candida diseases, developing new targeted drugs, and serves as a valuable reference for investigating the connection between mitochondria and virulence in other pathogenic fungi.}, }
@article {pmid38920876, year = {2024}, author = {Varghese, J and Ramenzoni, LL and Shenoy, PA and Schmidlin, PR and Mehrotra, S and Kamath, V}, title = {Injectable Platelet-Rich Fibrin and Advanced Platelet-Rich Fibrin Demonstrate Enhanced Anti-Biofilm Effect Compared to Enamel Matrix Derivatives on Decontaminated Titanium Surfaces.}, journal = {Dentistry journal}, volume = {12}, number = {6}, pages = {}, pmid = {38920876}, issn = {2304-6767}, abstract = {BACKGROUND: The search for effective antimicrobial agents to mitigate peri-implant infections remains a crucial aspect of implant dentistry. This study aimed to evaluate and compare the antimicrobial efficacy of i-PRF, A-PRF+, and enamel matrix derivative (EMD) on decontaminated rough and smooth titanium (Ti) discs.<br><br>MATERIALS AND METHODS: Rough and smooth Ti discs were coated with multispecies biofilm and thoroughly debrided using a chitosan-bristled brush. Subsequently, i-PRF, A-PRF+, and EMD were applied. Untreated discs served as control. Residual adherent bacteria present on the treated Ti discs were visualized by SEM and quantified using culture technique, and colony-forming units (CFUs) were measured after 48 h and 7 days.<br><br>RESULTS: i-PRF demonstrated better antimicrobial effectiveness on both smooth and rough implant surfaces as compared to A-PRF+ and EMD (p < 0.001). In all the experimental groups, smooth Ti discs displayed a greater reduction in microbes compared to rough Ti discs when treated with the biologics. The major reduction in CFU values was determined after seven days.<br><br>CONCLUSIONS: i-PRF as a regenerative material may also be suitable for decontaminating implant surfaces, which could influence tissue healing and regenerative outcomes positively.}, }
@article {pmid38919988, year = {2024}, author = {Lobo-Cabrera, FJ and Herrero, MDR and Govantes, F and Cuetos, A}, title = {Computer simulation study of nutrient-driven bacterial biofilm stratification.}, journal = {Journal of the Royal Society, Interface}, volume = {21}, number = {215}, pages = {20230618}, pmid = {38919988}, issn = {1742-5662}, support = {//Ministerio de Ciencia e Innovaci&#xf3;n/ ; //Consejeria de transformaci&#xf3;n econ&#xf3;mica Industria, Conocimiento y Universidades de la Junta de Andaluc&#xed;a/ ; }, mesh = {*Biofilms/growth &amp; development ; *Computer Simulation ; *Models, Biological ; Nutrients/metabolism ; Bacterial Physiological Phenomena ; Bacteria/metabolism/growth &amp; development ; }, abstract = {Here, employing computer simulation tools, we present a study on the development of a bacterial biofilm from a single starter cell on a flat inert surface overlaid by an aqueous solution containing nutrients. In our simulations, surface colonization involves an initial stage of two-dimensional cell proliferation to eventually transition to three-dimensional growth leading to the formation of biofilm colonies with characteristic three-dimensional semi-ellipsoids shapes. Thus, we have introduced the influence of the nutrient concentration on bacterial growth, and calculated the cell growth rate as a function of nutrient uptake, which in turn depends on local nutrient concentration in the vicinity of each bacterial cell. Our results show that the combination of cell growth and nutrient uptake and diffusion leads to the formation of stratified colonies containing an inner core in which nutrients are depleted and cells cannot grow or divide, surrounded by an outer, shallow crust in which cells have access to nutrients from the bulk medium and continue growing. This phenomenon is more apparent at high uptake rates that enable fast nutrient depletion. Our simulations also predict that the shape and internal structure of the biofilm are largely conditioned by the balance between nutrient diffusion and uptake.}, }
@article {pmid38919718, year = {2024}, author = {Gerardi, D and Bernardi, S and Bruni, A and Falisi, G and Botticelli, G}, title = {Characterization and morphological methods for oral biofilm visualization: where are we nowadays?.}, journal = {AIMS microbiology}, volume = {10}, number = {2}, pages = {391-414}, pmid = {38919718}, issn = {2471-1888}, abstract = {The oral microbiome represents an essential component of the oral ecosystem whose symbiotic relationship contributes to health maintenance. The biofilm represents a state of living of microorganisms surrounding themselves with a complex and tridimensional organized polymeric support and defense matrix. The substrates where the oral biofilm adhere can suffer from damages due to the microbial community metabolisms. Therefore, microbial biofilm represents the main etiological factor of the two pathologies of dental interest with the highest incidence, such as carious pathology and periodontal pathology. The study, analysis, and understanding of the characteristics of the biofilm, starting from the macroscopic structure up to the microscopic architecture, appear essential. This review examined the morphological methods used through the years to identify species, adhesion mechanisms that contribute to biofilm formation and stability, and how the action of microbicidal molecules is effective against pathological biofilm. Microscopy is the primary technique for the morphological characterization of biofilm. Light microscopy, which includes the stereomicroscope and confocal laser microscopy (CLSM), allows the visualization of microbial communities in their natural state, providing valuable information on the spatial arrangement of different microorganisms within the biofilm and revealing microbial diversity in the biofilm matrix. The stereomicroscope provides a three-dimensional view of the sample, allowing detailed observation of the structure, thickness, morphology, and distribution of the various species in the biofilm while CLSM provides information on its three-dimensional architecture, microbial composition, and dynamic development. Electron microscopy, scanning (SEM) or transmission (TEM), allows the high-resolution investigation of the architecture of the biofilm, analyzing the bacterial population, the extracellular polymeric matrix (EPS), and the mechanisms of the physical and chemical forces that contribute to the adhesion of the biofilm to the substrates, on a nanometric scale. More advanced microscopic methodologies, such as scanning transmission electron microscopy (STEM), high-resolution transmission electron microscopy (HR-TEM), and correlative microscopy, have enabled the evaluation of antibacterial treatments, due to the potential to reveal the efficacy of different molecules in breaking down the biofilm. In conclusion, evidence based on scientific literature shows that established microscopic methods represent the most common tools used to characterize biofilm and its morphology in oral microbiology. Further protocols and studies on the application of advanced microscopic techniques are needed to obtain precise details on the microbiological and pathological aspects of oral biofilm.}, }
@article {pmid38918119, year = {2024}, author = {Louzon, Y and Vaknin, I and Wolfoviz-Zilberman, A and Sharon, E and Houri-Haddad, Y and Beyth, N}, title = {In Vitro Effect of Streptococcus mutans Biofilm Produced in Sugar-Free Coca-Cola on Enamel.}, journal = {International dental journal}, volume = {}, number = {}, pages = {}, doi = {10.1016/j.identj.2024.05.008}, pmid = {38918119}, issn = {1875-595X}, abstract = {OBJECTIVE: Sugary drinks such as Coca-Cola may expedite dental caries. For this reason, sugar-free drinks like Coca-Cola Zero Sugar (CZ) may be considered advantageous. This research aims to evaluate in vitro the CZ effect in the presence of Streptococcus mutans (S. mutans) biofilm on enamel demineralization.<br><br>METHODS: Ninety-six human enamel slabs (4 &#xd7; 4 mm) were used. S. mutans UA-159 72-hour biofilm was created over enamel surfaces. The specimens were soaked in CZ, HCl, or 10% sucrose in PBS solution, 3 times a day for 15 minutes over the course of 4 days. Viable counts (CFU/mL) and biofilm biomass (Crystal Violet staining) were evaluated. pH was measured after each exposure. After 4 days, Demineralization was evaluated clinically and by Vickers microhardness tests. Slabs were photographed using a stereomicroscope before and after exposure to caries-promoting conditions.<br><br>RESULTS: Slabs that were soaked in CZ showed an increase in viable counts compared to control and almost similar counts with 10% sucrose in PBS solution exposures (10[10]and10[9]CFUmL, respectivly). Biofilm biomass tests showed a 25% higher bacterial growth in the CZ group. CZ pH measures were the lowest and the only group to show a decrease in pH over time (pH &#x223c;3). Enamel slabs that were evaluated clinically in the stereomicroscope postexposures had a chalky and matt appearance as opposed to their shiny appearance in the baseline evaluation.<br><br>CONCLUSIONS: CZ creates a favourable environment for the growth of S. mutans. It may be suggested that even though CZ is sugar free it has a cariogenic effect on enamel.<br><br>CLINICAL SIGNIFICANCE: Clinicians need to educate patients that sugar-free carbonated drinks may be just as harmful as regular carbonated drinks, and hence avoided. This research emphasizes the harmful effect sugar-free carbonated drinks on teeth and sheds new light on their cariogenic potential.}, }
@article {pmid38916438, year = {2024}, author = {Ye, Y and Zhang, L and Hong, X and Chen, M and Liu, X and Zhou, S}, title = {Interspecies ecological competition rejuvenates decayed Geobacter electroactive biofilm.}, journal = {The ISME journal}, volume = {18}, number = {1}, pages = {}, pmid = {38916438}, issn = {1751-7370}, support = {42222703//National Science Fund for Excellent Young Scholars of China/ ; 42077218//National Natural Science Foundation of China/ ; 2022&#xa0;J06015//Project of Fujian Provincial Department of Science and Technology of China/ ; }, mesh = {*Biofilms/growth &amp; development ; *Geobacter/genetics/physiology ; *Prophages/genetics/physiology ; Bioelectric Energy Sources/microbiology ; Microbial Interactions ; Transcriptome ; }, abstract = {Bioelectrochemical systems (BESs) exploit electroactive biofilms (EABs) for promising applications in biosensing, wastewater treatment, energy production, and chemical biosynthesis. However, during the operation of BESs, EABs inevitably decay. Seeking approaches to rejuvenate decayed EABs is critical for the sustainability and practical application of BESs. Prophage induction has been recognized as the primary reason for EAB decay. Herein, we report that introducing a competitive species of Geobacter uraniireducens suspended prophage induction in Geobacter sulfurreducens and thereby rejuvenated the decayed G. sulfurreducens EAB. The transcriptomic profile of G. sulfurreducens demonstrated that the addition of G. uraniireducens significantly affected the expression of metabolism- and stress response system-related genes and in particular suppressed the induction of phage-related genes. Mechanistic analyses revealed that interspecies ecological competition exerted by G. uraniireducens suppressed prophage induction. Our findings not only reveal a novel strategy to rejuvenate decayed EABs, which is significant for the sustainability of BESs, but also provide new knowledge for understanding phage-host interactions from an ecological perspective, with implications for developing therapies to defend against phage attack.}, }
@article {pmid38916322, year = {2024}, author = {Henríquez, L and Martín, C and Echeverz, M and Lasa, &#xcd; and Ezpeleta, C and Portillo, ME}, title = {Evaluation of the use of sonication combined with enzymatic treatment for biofilm removal in the microbiological diagnosis of prosthetic joint infection.}, journal = {Microbiology spectrum}, volume = {12}, number = {8}, pages = {e0002024}, pmid = {38916322}, issn = {2165-0497}, mesh = {Humans ; *Biofilms/growth &amp; development ; *Sonication/methods ; *Prosthesis-Related Infections/diagnosis/microbiology ; Female ; Middle Aged ; Aged ; Male ; Prospective Studies ; Adult ; Aged, 80 and over ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods ; Bacteria/isolation &amp; purification ; }, abstract = {UNLABELLED: Sonicating explanted prosthetic implants to physically remove biofilms is a recognized method for improving the microbiological diagnosis of prosthetic joint infection (PJI); however, chemical and enzymatic treatments have been investigated as alternative biofilm removal methods. We compared the biofilm dislodging efficacy of sonication followed by the addition of enzyme cocktails with different activity spectra in the diagnosis of PJI with that of the sonication of fluid cultures alone. Consecutive patients who underwent prosthesis explantation due to infection at our institution were prospectively enrolled for 1 year. The diagnostic procedure included the collection of five intraoperative tissue cultures, sonication of the removed devices, and conventional culture of the sonication fluid. The resulting sonication fluid was also treated with an enzyme cocktail consisting of homemade dispersin B (0.04 µg/mL) and proteinase K (Sigma; 100 µg/mL) for 45 minutes at 37°C. The resulting sonication (S) and sonication with subsequent enzymatic treatment (SE) fluids were plated for aerobic and anaerobic culture broth for 7 days (aerobic) or 14 days (anaerobic). Identification was performed by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (Bruker). We included 107 patients from whom a prosthetic implant had been removed, among which PJI was diagnosed in 36 (34%). The sensitivity of S alone was significantly greater than that of SE alone (82% vs 71%; P < 0.05). Four patients with PJI were positive after sonication alone but negative after sonication plus enzymatic treatment. The four microorganisms missed after the addition of the enzyme cocktail were Staphylococcus aureus, two coagulase-negative Staphylococci, and Cutibacterium acnes. In conclusion, sonication alone was more sensitive than sonication followed by enzymatic treatment. The combination of these two methods had no synergistic effect; in contrast, the results suggest that the combination of both dislodgment methods affects the viability of gram-positive microorganisms.<br><br>IMPORTANCE: While the potential of sonication and enzymes as biofilm dispersal agents has been previously described, the originality of our work resides in the combination of both methods, which is hypothesized to enhance the ability to remove biofilm and, therefore, improve the microbiological diagnosis of PJI.}, }
@article {pmid38916292, year = {2024}, author = {Jiang, G and Wang, C and Wang, Y and Wang, J and Xue, Y and Lin, Y and Hu, X and Lv, Y}, title = {Exogenous putrescine plays a switch-like influence on the pH stress adaptability of biofilm-based activated sludge.}, journal = {Applied and environmental microbiology}, volume = {90}, number = {7}, pages = {e0056924}, pmid = {38916292}, issn = {1098-5336}, support = {52170114//MOST | National Natural Science Foundation of China (NSFC)/ ; 21961160743//MOST | National Natural Science Foundation of China (NSFC)/ ; 21JCJQJC00080//Projects of Science and Technology, Tianjin/ ; B2021208033//Natural Science Foundation of Hebei Province/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; Hydrogen-Ion Concentration ; *Putrescine/metabolism/pharmacology ; *Sewage/microbiology ; Stress, Physiological ; Bacteria/metabolism/drug effects/genetics ; Adaptation, Physiological ; }, abstract = {Microbial community adaptability to pH stress plays a crucial role in biofilm formation. This study aims to investigate the regulatory mechanisms of exogenous putrescine on pH stress, as well as enhance understanding and application for the technical measures and molecular mechanisms of biofilm regulation. Findings demonstrated that exogenous putrescine acted as a switch-like distributor affecting microorganism pH stress, thus promoting biofilm formation under acid conditions while inhibiting it under alkaline conditions. As pH decreases, the protonation degree of putrescine increases, making putrescine more readily adsorbed. Protonated exogenous putrescine could increase cell membrane permeability, facilitating its entry into the cell. Subsequently, putrescine consumed intracellular H[+] by enhancing the glutamate-based acid resistance strategy and the γ-aminobutyric acid metabolic pathway to reduce acid stress on cells. Furthermore, putrescine stimulated ATPase expression, allowing for better utilization of energy in H[+] transmembrane transport and enhancing oxidative phosphorylation activity. However, putrescine protonation was limited under alkaline conditions, and the intracellular H[+] consumption further exacerbated alkali stress and inhibits cellular metabolic activity. Exogenous putrescine promoted the proportion of fungi and acidophilic bacteria under acidic stress and alkaliphilic bacteria under alkali stress while having a limited impact on fungi in alkaline biofilms. Increasing Bdellovibrio under alkali conditions with putrescine further aggravated the biofilm decomposition. This research shed light on the unclear relationship between exogenous putrescine, environmental pH, and pH stress adaptability of biofilm. By judiciously employing putrescine, biofilm formation could be controlled to meet the needs of engineering applications with different characteristics.IMPORTANCEThe objective of this study is to unravel the regulatory mechanism by which exogenous putrescine influences biofilm pH stress adaptability and understand the role of environmental pH in this intricate process. Our findings revealed that exogenous putrescine functioned as a switch-like distributor affecting the pH stress adaptability of biofilm-based activated sludge, which promoted energy utilization for growth and reproduction processes under acidic conditions while limiting biofilm development to conserve energy under alkaline conditions. This study not only clarified the previously ambiguous relationship between exogenous putrescine, environmental pH, and biofilm pH stress adaptability but also offered fresh insights into enhancing biofilm stability within extreme environments. Through the modulation of energy utilization, exerting control over biofilm growth and achieving more effective engineering goals could be possible.}, }
@article {pmid38914744, year = {2024}, author = {Bjerg, CSB and Poehlein, A and Bömeke, M and Himmelbach, A and Schramm, A and Brüggemann, H}, title = {Increased biofilm formation in dual-strain compared to single-strain communities of Cutibacterium acnes.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {14547}, pmid = {38914744}, issn = {2045-2322}, support = {LF-OC-21-000826//LEO Fondet/ ; }, mesh = {*Biofilms/growth &amp; development ; Propionibacteriaceae/genetics/physiology/isolation &amp; purification ; Humans ; Coculture Techniques ; Gene Expression Regulation, Bacterial ; Gene Expression Profiling ; In Situ Hybridization, Fluorescence ; }, abstract = {Cutibacterium acnes is a known opportunistic pathogen in orthopedic implant-associated infections (OIAIs). The species of C. acnes comprises distinct phylotypes. Previous studies suggested that C. acnes can cause single- as well as multi-typic infections, i.e. infections caused by multiple strains of different phylotypes. However, it is not known if different C. acnes phylotypes are organized in a complex biofilm community, which could constitute a multicellular strategy to increase biofilm strength and persistency. Here, the interactions of two C. acnes strains belonging to phylotypes IB and II were determined in co-culture experiments. No adverse interactions between the strains were observed in liquid culture or on agar plates; instead, biofilm formation in both microtiter plates and on titanium discs was significantly increased when combining both strains. Fluorescence in situ hybridization showed that both strains co-occurred throughout the biofilm. Transcriptome analyses revealed strain-specific alterations of gene expression in biofilm-embedded cells compared to planktonic growth, in particular affecting genes involved in carbon and amino acid metabolism. Overall, our results provide first insights into the nature of dual-type biofilms of C. acnes, suggesting that strains belonging to different phylotypes can form biofilms together with additive effects. The findings might influence the perception of C. acnes OIAIs in terms of diagnosis and treatment.}, }
@article {pmid38914199, year = {2024}, author = {Battulga, B and Munkhbat, D and Matsueda, M and Atarashi-Andoh, M and Oyuntsetseg, B and Koarashi, J and Kawahigashi, M}, title = {Uncovering the characteristics of plastic-associated biofilm from the inland river system of Mongolia.}, journal = {Environmental pollution (Barking, Essex : 1987)}, volume = {357}, number = {}, pages = {124427}, doi = {10.1016/j.envpol.2024.124427}, pmid = {38914199}, issn = {1873-6424}, mesh = {*Biofilms ; *Rivers/chemistry/microbiology ; Mongolia ; *Plastics/analysis ; *Environmental Monitoring/methods ; Water Pollutants, Chemical/analysis ; }, abstract = {The occurrence and characteristics of plastic debris in aquatic and terrestrial environments have been extensively studied. However, limited information exists on the properties and dynamic behavior of plastic-associated biofilms in the environment. In this study, we collected plastic samples from an inland river system in Mongolia and extracted biofilms to uncover their characteristics using spectroscopic, isotopic, and thermogravimetric techniques. Mixtures of organic and mineral particles were detected in the extracted biofilms, revealing plastic as a carrier for exogenous substances, including contaminants, in the river ecosystem. Thermogravimetric analysis (TGA) indicated the predominant contribution of minerals primarily comprising aluminosilicate and calcite, representing approximately 80 wt% of the biofilms. Differential thermal analysis (DTA) coupled with Fourier transform infrared (FTIR) spectrometry operated at 25°C-600 °C enabled the detection of gaseous decomposition products, such as CO2, H2O, CO, and functional groups (O-H, C-H, C-O, CO, CC, and C-C), released from biopolymers in the extracted biofilms. Dehydration, dehydroxylation, and decarboxylation reactions explain the thermal properties of biofilms. The stable carbon (δ[13]C) and nitrogen (δ[15]N) isotope ratios of the biofilms demonstrated variable signatures ranging from -24.1‰ to -27.0‰ and 3.1‰-12.3‰, respectively. A significant difference in the δ[13]C value (p < 0.05) among the upstream, middle, and downstream research sites could be characterized by available organic carbon sources in the river environment, depending on the research sites. This study provides insights into the characteristics and environmental behavior of biofilms which are useful to elucidate the impact of plastic-associated biofilms on organic matter and material cycling in aquatic ecosystems.}, }
@article {pmid38910428, year = {2024}, author = {Masadeh, MM and Alshogran, H and Alsaggar, M and Sabi, SH and Al Momany, EM and Masadeh, MM and Alrabadi, N and Alzoubi, KH}, title = {Evaluation of Novel HLM Peptide Activity and Toxicity against Planktonic and Biofilm Bacteria: Comparison to Standard Antibiotics.}, journal = {Current protein &amp; peptide science}, volume = {25}, number = {10}, pages = {826-843}, pmid = {38910428}, issn = {1875-5550}, support = {//Jordan University of Science and Technology/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology/chemistry ; Animals ; *Antimicrobial Cationic Peptides/pharmacology/chemistry ; Vero Cells ; Chlorocebus aethiops ; Hemolysis/drug effects ; Plankton/drug effects ; Cathelicidins/pharmacology ; Escherichia coli/drug effects ; Humans ; Staphylococcus aureus/drug effects ; Methicillin-Resistant Staphylococcus aureus/drug effects ; Drug Synergism ; Proteins ; }, abstract = {BACKGROUND: Antibiotic resistance is one of the main concerns of public health, and the whole world is trying to overcome such a challenge by finding novel therapeutic modalities and approaches. This study has applied the sequence hybridization approach to the original sequence of two cathelicidin natural parent peptides (BMAP-28 and LL-37) to design a novel HLM peptide with broad antimicrobial activity.<br><br>METHODS: The physicochemical characteristics of the newly designed peptide were determined. As well, the new peptide's antimicrobial activity (Minimum Inhibitory Concentration (MIC), Minimum Bacterial Eradication Concentration (MBEC), and antibiofilm activity) was tested on two control (Staphylococcus aureus ATCC 29213, Escherichia coli ATCC 25922) and two resistant (Methicillin-resistant Staphylococcus aureus (MRSA) ATCC BAA41, New Delhi metallo-beta- lactamase-1 Escherichia coli ATCC BAA-2452) bacterial strains. Furthermore, synergistic studies have been applied to HLM-hybridized peptides with five conventional antibiotics by checkerboard assays. Also, the toxicity of HLM-hybridized peptide was studied on Vero cell lines to obtain the IC50 value. Besides the percentage of hemolysis action, the peptide was tested in freshly heparinized blood.<br><br>RESULTS: The MIC values for the HLM peptide were obtained as 20, 10, 20, and 20 &#x3bc;M, respectively. Also, the results showed no hemolysis action, with low to slightly moderate toxicity action against mammalian cells, with an IC50 value of 10.06. The Biomatik corporate labs, where HLM was manufactured, determined the stability results of the product by Mass Spectrophotometry (MS) and High-performance Liquid Chromatography (HPLC) methods. The HLM-hybridized peptide exhibited a range of synergistic to additive antimicrobial activities upon combination with five commercially available different antibiotics. It has demonstrated the biofilm-killing effects in the same concentration required to eradicate the control strains.<br><br>CONCLUSION: The results indicated that HLM-hybridized peptide displayed a broad-spectrum activity toward different bacterial strains in planktonic and biofilm forms. It showed synergistic or additive antimicrobial activity upon combining with commercially available different antibiotics.}, }
@article {pmid38909125, year = {2024}, author = {Verheul, M and Mulder, AA and van Dun, SCJ and Merabishvili, M and Nelissen, RGHH and de Boer, MGJ and Pijls, BG and Nibbering, PH}, title = {Bacteriophage ISP eliminates Staphylococcus aureus in planktonic phase, but not in the various stages of the biofilm cycle.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {14374}, pmid = {38909125}, issn = {2045-2322}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Staphylococcus aureus/virology/drug effects/physiology ; *Staphylococcus Phages/physiology ; *Plankton ; Staphylococcal Infections/microbiology/therapy ; Humans ; Bacteriophages/physiology ; }, abstract = {Metal-implant associated bacterial infections are a major clinical problem due to antibiotic treatment failure. As an alternative, we determined the effects of bacteriophage ISP on clinical isolates of Staphylococcus aureus in various stages of its life cycle in relation to biofilm formation and maturation. ISP effectively eliminated all planktonic phase bacteria, whereas its efficacy was reduced against bacteria attached to the metal implant and bacteria embedded within biofilms. The biofilm architecture hampered the bactericidal effects of ISP, as mechanical disruption of biofilms improved the efficacy of ISP against the bacteria. Phages penetrated the biofilm and interacted with the bacteria throughout the biofilm. However, most of the biofilm-embedded bacteria were phage-tolerant. In agreement, bacteria dispersed from mature biofilms of all clinical isolates, except for LUH15394, tolerated the lytic activity of ISP. Lastly, persisters within mature biofilms tolerated ISP and proliferated in its presence. Based on these findings, we conclude that ISP eliminates planktonic phase Staphylococcus aureus while its efficacy is limited against bacteria attached to the metal implant, embedded within (persister-enriched) biofilms, and dispersed from biofilms.}, }
@article {pmid38907796, year = {2024}, author = {Huang, Q and Zhang, M and Zhang, Y and Li, X and Luo, X and Ji, S and Lu, R}, title = {IcmF2 of the type VI secretion system 2 plays a role in biofilm formation of Vibrio parahaemolyticus.}, journal = {Archives of microbiology}, volume = {206}, number = {7}, pages = {321}, pmid = {38907796}, issn = {1432-072X}, support = {2023JQ011//Special Project on Clinical Medicine of Nantong University/ ; 2023JQ017//Special Project on Clinical Medicine of Nantong University/ ; QN2023032//Research Project of Nantong Health Commission/ ; }, mesh = {*Vibrio parahaemolyticus/genetics/physiology/metabolism ; *Biofilms/growth &amp; development ; *Type VI Secretion Systems/genetics/metabolism ; *Bacterial Proteins/genetics/metabolism ; *Cyclic GMP/analogs &amp; derivatives/metabolism ; Humans ; Gene Expression Regulation, Bacterial ; HeLa Cells ; }, abstract = {Vibrio parahaemolyticus possesses two distinct type VI secretion systems (T6SS), namely T6SS1 and T6SS2. T6SS1 is predominantly responsible for adhesion to Caco-2 and HeLa cells and for the antibacterial activity of V. parahaemolyticus, while T6SS2 mainly contributes to HeLa cell adhesion. However, it remains unclear whether the T6SS systems have other physiological roles in V. parahaemolyticus. In this study, we demonstrated that the deletion of icmF2, a structural gene of T6SS2, reduced the biofilm formation capacity of V. parahaemolyticus under low salt conditions, which was also influenced by the incubation time. Nonetheless, the deletion of icmF2 did not affect the biofilm formation capacity in marine-like growth conditions, nor did it impact the flagella-driven swimming and swarming motility of V. parahaemolyticus. IcmF2 was found to promote the production of the main components of the biofilm matrix, including extracellular DNA (eDNA) and extracellular proteins, and cyclic di-GMP (c-di-GMP) in V. parahaemolyticus. Additionally, IcmF2 positively influenced the transcription of cpsA, mfpA, and several genes involved in c-di-GMP metabolism, including scrJ, scrL, vopY, tpdA, gefA, and scrG. Conversely, the transcription of scrA was negatively impacted by IcmF2. Therefore, IcmF2-dependent biofilm formation was mediated through its effects on the production of eDNA, extracellular proteins, and c-di-GMP, as well as its impact on the transcription of cpsA, mfpA, and genes associated with c-di-GMP metabolism. This study confirmed new physiological roles for IcmF2 in promoting biofilm formation and c-di-GMP production in V. parahaemolyticus.}, }
@article {pmid38906456, year = {2024}, author = {Kim, HT and Jo, YH and Jee, EB and Yoon, HI and Yilmaz, B}, title = {Effect of postpolymerization time and atmosphere on surface properties and biofilm formation in additively manufactured resins for definitive restorations.}, journal = {Journal of dentistry}, volume = {147}, number = {}, pages = {105143}, doi = {10.1016/j.jdent.2024.105143}, pmid = {38906456}, issn = {1879-176X}, mesh = {*Surface Properties ; *Biofilms/drug effects ; *Polymerization ; *Bacterial Adhesion/drug effects ; *Materials Testing ; Time Factors ; *Composite Resins/chemistry ; Dental Materials/chemistry ; Adsorption ; Dental Restoration, Permanent ; Humans ; Methacrylates/chemistry ; Atmosphere ; Nitrogen/chemistry ; Streptococcus mutans/drug effects ; Polyurethanes/chemistry ; }, abstract = {OBJECTIVES: To investigate how postpolymerization time (PPT) and atmosphere (PPA) influence the surface properties, protein adsorption, and microbial adhesion of two types of additively manufactured (AM) resins used for definitive restorations.<br><br>METHODS: Two different types of commercially available AM resins for definitive restorations (UR and CR) were used to create disk-shaped specimens. These specimens were divided into eight groups based on resin type (UR and CR), PPT (standard or extended), and PPA (air or nitrogen). After postpolymerization, the surface roughness (Ra and Sa) and surface free energy (SFE) of all specimens were measured. The study also evaluated protein adsorption, microbial attachment, and cytotoxicity. A non-parametric factorial analysis of variance with post-hoc analyses was conducted, using a significance level (&#x3b1;) of 0.05.<br><br>RESULTS: The Ra and Sa values for CR were higher than those for UR, regardless of PPT or PPA (P < 0.05). For UR, SFE was higher with extended PPT compared to standard PPT. CR had higher SFE than UR under standard PPT. The interaction between PPT and PPA had a significant effect on protein adsorption (P < 0.05). When PPT was standard, nitrogen significantly increased protein adsorption compared to air. The interaction between resin type and PPA, and between resin type and PPT, significantly affected microbial adhesion (P < 0.05). The changes in PPT or PPA did not affect the cytotoxicity of either AM resin.<br><br>CONCLUSION: Surface properties, protein adsorption, and microbial attachment were influenced by the interactions among PPT, PPA, and resin type. These factors can have implications for resin-based definitive restorations.<br><br>CLINICAL SIGNIFICANCES: Clinicians should understand the impact of PPT and PPA on the surface properties of AM resins for definitive restorations, particularly regarding protein adsorption and microbial adhesion. Additionally, the type of AM resin (based on chemical composition) could affect its biological properties.}, }
@article {pmid38905973, year = {2024}, author = {Wang, H and Hu, C and Li, Y and Shen, Y and Guo, J and Shi, B and Alvarez, PJJ and Yu, P}, title = {Nano-sized polystyrene and magnetite collectively promote biofilm stability and resistance due to enhanced oxidative stress response.}, journal = {Journal of hazardous materials}, volume = {476}, number = {}, pages = {134974}, doi = {10.1016/j.jhazmat.2024.134974}, pmid = {38905973}, issn = {1873-3336}, mesh = {*Biofilms/drug effects ; *Oxidative Stress/drug effects ; *Pseudomonas aeruginosa/drug effects ; *Polystyrenes/toxicity/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry/toxicity ; *Reactive Oxygen Species/metabolism ; Nanoparticles/toxicity/chemistry ; Ferrosoferric Oxide/chemistry/toxicity ; Quorum Sensing/drug effects ; Drug Resistance, Bacterial/drug effects ; Magnetite Nanoparticles/toxicity/chemistry ; Microbial Sensitivity Tests ; }, abstract = {Despite the growing prevalence of nanoplastics in drinking water distribution systems, the collective influence of nanoplastics and background nanoparticles on biofilm formation and microbial risks remains largely unexplored. Here, we demonstrate that nano-sized polystyrene modified with carboxyl groups (nPS) and background magnetite (nFe3O4) nanoparticles at environmentally relevant concentrations can collectively stimulate biofilm formation and prompt antibiotic resistance. Combined exposure of nPS and nFe3O4 by P. aeruginosa biofilm cells stimulated intracellular reactive oxidative species (ROS) production more significantly compared with individual exposure. The resultant upregulation of quorum sensing (QS) and c-di-GMP signaling pathways enhanced the biosynthesis of polysaccharides by 50 %- 66 % and increased biofilm biomass by 36 %- 40 % relative to unexposed control. Consistently, biofilm mechanical stability (measured as Young's modulus) increased by 7.2-9.1 folds, and chemical stress resistance (measured with chlorine disinfection) increased by 1.4-2.0 folds. For P. aeruginosa, the minimal inhibitory concentration of different antibiotics also increased by 1.1-2.5 folds after combined exposure. Moreover, at a microbial community-wide level, metagenomic analysis revealed that the combined exposure enhanced the multi-species biofilm's resistance to chlorine, enriched the opportunistic pathogenic bacteria, and promoted their virulence and antibiotic resistance. Overall, the enhanced formation of biofilms (that may harbor opportunistic pathogens) by nanoplastics and background nanoparticles is an overlooked phenomenon, which may jeopardize the microbial safety of drinking water distribution systems.}, }
@article {pmid38905793, year = {2024}, author = {Ferreira, AR and Skjolding, LM and Sanchez, DF and Bernar Ntynez, AG and Ivanova, YD and Feilberg, KL and Chhetri, RK and Andersen, HR}, title = {Offshore produced water treatment by a biofilm reactor on the seabed: The effect of temperature and matrix characteristics.}, journal = {Journal of environmental management}, volume = {365}, number = {}, pages = {121391}, doi = {10.1016/j.jenvman.2024.121391}, pmid = {38905793}, issn = {1095-8630}, mesh = {*Biofilms ; *Bioreactors ; *Temperature ; Water Purification/methods ; Salinity ; Biological Oxygen Demand Analysis ; Water Pollutants, Chemical ; }, abstract = {In many industrial processes a large amount of water with high salinity is co-produced whose treatment poses considerable challenges to the available technologies. The produced water (PW) from offshore operations is currently being discharged to sea without treatment for dissolved pollutants due to space limitations. A biofilter on the seabed adjacent to a production platform would negate all size restrictions, thus reducing the environmental impact of oil and gas production offshore. The moving bed biofilm reactor (MBBR) was investigated for PW treatment from different oilfields in the North Sea at 10 °C and 40 °C, corresponding to the sea and PW temperature, respectively. The six PW samples in study were characterized by high salinity and chemical oxygen demand with ecotoxic effects on marine algae S. pseudocostatum (0.4%<EC50<2.7%). In continuous operation over a year, MBBR achieved a stable COD removal of 64 ± 5% at 10 °C and 68 ± 8% at 40 °C. Batch experiments revealed that most dissolved compounds were removed (up to 63%) within 3 h of treatment. High temperature (40 °C) was a key parameter to achieve a faster kinetics with degradation constant rate (k) up to eight-fold faster compared to 10 °C. Alongside contaminants removal, PW toxicity was also reduced (64-89%) during MBBR at both temperatures, hot and cold. The toxicity reduction was most likely related to the elimination of dissolved organic compounds, such as phenols, naphthalenes and BTEX. The biofilm was able to handle PW with high oil in water content from unstable production, as well as high salinity. Thus, MBBR seems to be a realistic solution to treat PW with complex and variable composition by removing harmful components towards the zero harmful discharge goal.}, }
@article {pmid38905306, year = {2024}, author = {Rai, LS and Chauvel, M and Sanchez, H and van Wijlick, L and Maufrais, C and Cokelaer, T and Sertour, N and Legrand, M and Sanyal, K and Andes, DR and Bachellier-Bassi, S and d'Enfert, C}, title = {Metabolic reprogramming during Candida albicans planktonic-biofilm transition is modulated by the transcription factors Zcf15 and Zcf26.}, journal = {PLoS biology}, volume = {22}, number = {6}, pages = {e3002693}, pmid = {38905306}, issn = {1545-7885}, mesh = {*Biofilms/growth &amp; development ; *Candida albicans/genetics/metabolism/physiology ; *Transcription Factors/metabolism/genetics ; *Fungal Proteins/metabolism/genetics ; *Gene Expression Regulation, Fungal ; Animals ; Plankton/metabolism ; Glyoxylates/metabolism ; Gene Expression Profiling/methods ; Mice ; Citric Acid Cycle ; Hyphae/metabolism/growth &amp; development/genetics ; Candidiasis/microbiology ; Metabolic Reprogramming ; }, abstract = {Candida albicans is a commensal of the human microbiota that can form biofilms on implanted medical devices. These biofilms are tolerant to antifungals and to the host immune system. To identify novel genes modulating C. albicans biofilm formation, we performed a large-scale screen with 2,454 C. albicans doxycycline-dependent overexpression strains and identified 16 genes whose overexpression significantly hampered biofilm formation. Among those, overexpression of the ZCF15 and ZCF26 paralogs that encode transcription factors and have orthologs only in biofilm-forming species of the Candida clade, caused impaired biofilm formation both in vitro and in vivo. Interestingly, overexpression of ZCF15 impeded biofilm formation without any defect in hyphal growth. Transcript profiling, transcription factor binding, and phenotypic microarray analyses conducted upon overexpression of ZCF15 and ZCF26 demonstrated their role in reprogramming cellular metabolism by regulating central metabolism including glyoxylate and tricarboxylic acid cycle genes. Taken together, this study has identified a new set of biofilm regulators, including ZCF15 and ZCF26, that appear to control biofilm development through their specific role in metabolic remodeling.}, }
@article {pmid38904296, year = {2024}, author = {Kulshrestha, A and Gupta, P}, title = {Real-time biofilm detection techniques: advances and applications.}, journal = {Future microbiology}, volume = {19}, number = {11}, pages = {1003-1016}, pmid = {38904296}, issn = {1746-0921}, mesh = {*Biofilms/growth &amp; development ; Humans ; Bacteria/isolation &amp; purification/growth &amp; development/genetics ; Electrochemical Techniques/methods ; }, abstract = {Microbial biofilms, complex assemblies enveloped in extracellular matrices, are significant contributors to various infections. Traditional in vitro biofilm characterization methods, though informative, often disrupt the biofilm structure. The need to address biofilm-related infections urgently emphasizes the importance of continuous monitoring and timely interventions. This review provides a focused examination of advancements in real-time biofilm detection techniques, specifically in electrochemical, optical and mechanical systems. The potential applications of real-time detection in managing and monitoring biofilm growth in industrial settings, preventing medical infections, comprehending biofilm dynamics and evaluating control strategies highlight the necessity for it. Crucially, the review emphasizes the importance of evaluating these methods for their accuracy and reliability in real-time biofilm detection, offering valuable insights for precise interventions across various applications.}, }
@article {pmid38903941, year = {2024}, author = {Shaik, S and Lee, JH and Kim, YG and Lee, J}, title = {Antifungal, anti-biofilm, and anti-hyphal properties of N-substituted phthalimide derivatives against Candida species.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1414618}, pmid = {38903941}, issn = {2235-2988}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Antifungal Agents/pharmacology ; *Phthalimides/pharmacology ; *Microbial Sensitivity Tests ; *Candida albicans/drug effects ; *Hyphae/drug effects/growth &amp; development ; Candida/drug effects ; Candidiasis/microbiology/drug therapy ; Animals ; Humans ; Candida parapsilosis/drug effects ; Fungal Proteins/genetics/metabolism ; Fluconazole/pharmacology ; }, abstract = {Candida species comprise a ubiquitous pathogenic fungal genus responsible for causing candidiasis. They are one of the primary causatives of several mucosal and systemic infections in humans and can survive in various environments. In this study, we investigated the antifungal, anti-biofilm, and anti-hyphal effects of six N-substituted phthalimides against three Candida species. Of the derivatives, N-butylphthalimide (NBP) was the most potent, with a minimum inhibitory concentration (MIC) of 100 µg/ml and which dose-dependently inhibited biofilm at sub-inhibitory concentrations (10-50 µg/ml) in both the fluconazole-resistant and fluconazole-sensitive Candida albicans and Candida parapsilosis. NBP also effectively inhibited biofilm formation in other pathogens including uropathogenic Escherichia coli, Staphylococcus epidermidis, Staphylococcus aureus, and Vibrio parahaemolyticus, along with the polymicrobial biofilms of S. epidermidis and C. albicans. NBP markedly inhibited the hyphal formation and cell aggregation of C. albicans and altered its colony morphology in a dose-dependent manner. Gene expression analysis showed that NBP significantly downregulated the expression of important hyphal- and biofilm-associated genes, i.e., ECE1, HWP1, and UME6, upon treatment. NBP also exhibited mild toxicity at concentrations ranging from 2 to 20 µg/ml in a nematode model. Therefore, this study suggests that NBP has anti-biofilm and antifungal potential against various Candida strains.}, }
@article {pmid38903792, year = {2024}, author = {Nishimura, A and Tanahashi, R and Nakagami, K and Morioka, Y and Takagi, H}, title = {The arginine transporter Can1 negatively regulates biofilm formation in yeasts.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1419530}, pmid = {38903792}, issn = {1664-302X}, abstract = {The arginine transporter Can1 is a multifunctional protein of the conventional yeast Saccharomyces cerevisiae. Apart from facilitating arginine uptake, Can1 plays a pivotal role in regulating proline metabolism and maintaining cellular redox balance. Here, we report a novel function of Can1 in the control of yeast biofilm formation. First, the S. cerevisiae CAN1 gene knockout strain displayed a significant growth delay compared to the wild-type strain. Our genetic screening revealed that the slow growth of the CAN1 knockout strain is rescued by a functional deficiency of the FLO8 gene, which encodes the master transcription factor associated with biofilm formation, indicating that Can1 is involved in biofilm formation. Intriguingly, the CAN1 knockout strain promoted the Flo11-dependent aggregation, leading to higher biofilm formation. Furthermore, the CAN1 knockout strain of the pathogenic yeast Candida glabrata exhibited slower growth and higher biofilm formation, similar to S. cerevisiae. More importantly, the C. glabrata CAN1 gene knockout strain showed severe toxicity to macrophage-like cells and nematodes. The present results could help to elucidate both the molecular mechanism underlying yeast biofilm formation and the role it plays. Future investigations may offer insights that contribute to development of antibiofilm agents.}, }
@article {pmid38902342, year = {2024}, author = {Chalipa, Z and Hosseinzadeh, M and Nikoo, MR}, title = {Performance evaluation of a new sponge-based moving bed biofilm reactor for the removal of pharmaceutical pollutants from real wastewater.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {14240}, pmid = {38902342}, issn = {2045-2322}, mesh = {*Bioreactors ; *Wastewater/chemistry ; *Water Pollutants, Chemical/isolation &amp; purification/analysis ; *Biofilms ; *Biological Oxygen Demand Analysis ; *Ibuprofen/isolation &amp; purification ; Water Purification/methods/instrumentation ; Waste Disposal, Fluid/methods ; Animals ; }, abstract = {Pharmaceutical pollutants, a group of emerging contaminants, have attracted outstanding attention in recent years, and their removal from aquatic environments has been addressed. In the current study, a new sponge-based moving bed biofilm reactor (MBBR) was developed to remove chemical oxygen demand (COD) and the pharmaceutical compound Ibuprofen (IBU). A 30-L pilot scale MBBR was constructed, which was continuously fed from the effluent of the first clarifier of the Southern Tehran wastewater treatment plant. The controlled operational parameters were pH in the natural range, Dissolved Oxygen of 1.5-2 mg/L, average suspended mixed liquor suspended solids (MLSS), and mixed liquor volatile suspended solids (MLVSS) of 1.68 ± 0.1 g/L and 1.48 ± 0.1 g/L, respectively. The effect of hydraulic retention time (HRT) (5 h, 10 h, 15 h), filling ratio (10%, 20%, 30%), and initial IBU concentration (2 mg/L, 5 mg/L, 10 mg/L) on removal efficiencies was assessed. The findings of this study revealed a COD removal efficiency ranging from 48.9 to 96.7%, with the best removal efficiency observed at an HRT of 10 h, a filling ratio of 20%, and an initial IBU concentration of 2 mg/L. Simultaneously, the IBU removal rate ranged from 25 to 92.7%, with the highest removal efficiency observed under the same HRT and filling ratio, albeit with an initial IBU concentration of 5 mg/L. An extension of HRT from 5 to 10 h significantly improved both COD and IBU removal. However, further extension from 10 to 15 h slightly enhanced the removal efficiency of COD and IBU, and even in some cases, removal efficiency decreased. Based on the obtained results, 20% of the filling ratio was chosen as the optimum state. Increasing the initial concentration of IBU from 2 to 5 mg/L generally improved COD and IBU removal, whereas an increase from 5 to 10 mg/L caused a decline in COD and IBU removal. This study also optimized the reactor's efficiency for COD and IBU removal by using response surface methodology (RSM) with independent variables of HRT, filling ratio, and initial IBU concentration. In this regard, the quadratic model was found to be significant. Utilizing the central composite design (CCD), the optimal operating parameters at an HRT of 10 h, a filling ratio of 21%, and an initial IBU concentration of 3 mg/L were pinpointed, achieving the highest COD and IBU removal efficiencies. The present study demonstrated that sponge-based MBBR stands out as a promising technology for COD and IBU removal.}, }
@article {pmid38901747, year = {2024}, author = {Li, YQ and Zhang, CM and Wang, Q and Jiao, XR}, title = {Metagenomic insights into effects of carbon/nitrogen ratio on microbial community and antibiotic resistance in moving bed biofilm reactor.}, journal = {Bioresource technology}, volume = {406}, number = {}, pages = {131007}, doi = {10.1016/j.biortech.2024.131007}, pmid = {38901747}, issn = {1873-2976}, mesh = {*Biofilms/drug effects ; *Carbon/pharmacology ; *Nitrogen ; *Bioreactors/microbiology ; *Metagenomics/methods ; Drug Resistance, Microbial/genetics ; Microbiota/drug effects ; Bacteria/drug effects/genetics ; }, abstract = {This study investigated the effects of carbon/nitrogen (C/N) ratio on microbial community in moving bed biofilm reactor (MBBR) using metagenomic analysis, and the dynamic changes of relevant antibiotic resistance genes (ARGs) were also analyzed. The results showed that under low C/N ratio, MBBR exhibited average removal rates of 98.41 % for ammonia nitrogen and 75.79 % for total nitrogen. Metagenomic analysis showed low C/N ratio altered the structure of biofilm and water microbiota, resulting in the detachment of bacteria such as Actinobacteria from biofilm into water. Furthermore, sulfamethazine (SMZ)-resistant bacteria and related ARGs were released into water under low C/N ratio, which lead to the increase of SMZ resistance rate to 90%. Moreover, most dominant genera are potential hosts for both nitrogen cycle related genes and ARGs. Specifically, Nitrosomonas that carried gene sul2 might be released from biofilm into water. These findings implied the risks of antibiotic resistance dissemination in MBBR under low C/N ratio.}, }
@article {pmid38901318, year = {2024}, author = {Corsino, SF and Bruno, F and Di Bella, G}, title = {Nutrients removal in overloaded WWTP by intermittently aerated IFAS: Effects of biofilm carrier and intermittent aeration cycle.}, journal = {Journal of environmental management}, volume = {365}, number = {}, pages = {121516}, doi = {10.1016/j.jenvman.2024.121516}, pmid = {38901318}, issn = {1095-8630}, mesh = {*Biofilms ; *Waste Disposal, Fluid/methods ; *Phosphorus/metabolism ; *Nitrogen/metabolism ; Wastewater/chemistry ; Sewage ; Denitrification ; Bioreactors ; Nutrients/metabolism ; Carbon/metabolism ; Nitrification ; Water Purification/methods ; }, abstract = {Updating of the current Urban Waste Water Treatment Directive (91/271/EEC) will demand stricter regulations for nutrients removal. In this frame, wastewater treatment plants (WWTPs) of small-to-medium potential will face new challenges for achieving process intensification. Integrating intermittent aeration (IA) and integrated fixed-film activated sludge (IFAS) technologies could be a promising solution to meet such requirements. This study analyzed how IA cycles affected nutrients removal in IFAS reactors with different biofilm carriers (e.g., plastic and sponge media). The plants responses to different carbon/nitrogen/phosphorous (C/N/P) ratios were evaluated while operating under low sludge retention time (SRT) to simulate overloaded conditions. A short IA cycle (1 h) with an aeration/not aeration ratio of 2:1 enabled high organic carbon and nitrification performances when operating at high C/N/P (11.8/1/1), whereas low denitrification and phosphorous removal yields were obtained because of the short not-aerated phase. Decreasing C/N ratio (8.8/1/1) without changing the IA cycle resulted in nitrification worsening because of the reduced metabolic kinetics of biofilm. Under such load conditions, a higher IA cycle (2 h) was necessary to improve process performance. A longer not-aerated phase was also positive for denitrification and phosphorous removal because of the establishment of anoxic and anaerobic environments within the bulk and inner biofilm layers. Besides, results suggested that sponge carriers offered advantages over plastic ones, enabling a higher biofilm retention capacity, better nutrient removal, as well as robustness and resilience to operating condition changes. This would result in simpler management systems for implementing the IA process, thus reducing process complexity and costs.}, }
@article {pmid38901258, year = {2024}, author = {Meng, L and Liang, L and Shi, Y and Yin, H and Li, L and Xiao, J and Huang, N and Zhao, A and Xia, Y and Hou, J}, title = {Biofilms in plastisphere from freshwater wetlands: Biofilm formation, bacterial community assembly, and biogeochemical cycles.}, journal = {Journal of hazardous materials}, volume = {476}, number = {}, pages = {134930}, doi = {10.1016/j.jhazmat.2024.134930}, pmid = {38901258}, issn = {1873-3336}, mesh = {*Biofilms/growth &amp; development ; *Wetlands ; *Bacteria/genetics/classification/metabolism ; *Fresh Water/microbiology ; Microplastics ; Soil Microbiology ; Microbiota ; Water Pollutants, Chemical/analysis ; }, abstract = {Microorganisms can colonize to the surface of microplastics (MPs) to form biofilms, termed "plastisphere", which could significantly change their physiochemical properties and ecological roles. However, the biofilm characteristics and the deep mechanisms (interaction, assembly, and biogeochemical cycles) underlying plastisphere in wetlands currently lack a comprehensive perspective. In this study, in situ biofilm formation experiments were performed in a park with different types of wetlands to examine the plastisphere by extrinsic addition of PVC MPs in summer and winter, respectively. Results from the spectroscopic and microscopic analyses revealed that biofilms attached to the MPs in constructed forest wetlands contained the most abundant biomass and extracellular polymeric substances. Meanwhile, data from the high-throughput sequencing showed lower diversity in plastisphere compared with soil bacterial communities. Network analysis suggested a simple and unstable co-occurrence pattern in plastisphere, and the null model indicated increased deterministic process of heterogeneous selection for its community assembly. Based on the quantification of biogeochemical cycling genes by high-throughput qPCR, the relative abundances of genes involving in carbon degradation, carbon fixation, and denitrification were significantly higher in plastisphere than those of soil communities. This study greatly enhanced our understanding of biofilm formation and ecological effects of MPs in freshwater wetlands.}, }
@article {pmid38901063, year = {2024}, author = {Xu, G and Peng, G and Yang, J and Wu, M and Li, W and Wang, J and Zhu, L and Zhang, W and Ge, F and Song, P}, title = {Molybdenum disulfide nanosheets based non-oxygen-dependent and heat-initiated free radical nanogenerator with antimicrobial peptides for antimicrobial, biofilm ablation and wound healing.}, journal = {Biomaterials advances}, volume = {162}, number = {}, pages = {213920}, doi = {10.1016/j.bioadv.2024.213920}, pmid = {38901063}, issn = {2772-9508}, mesh = {*Biofilms/drug effects ; *Wound Healing/drug effects ; Animals ; Mice ; *Disulfides/chemistry/pharmacology ; *Molybdenum/chemistry/pharmacology ; *Escherichia coli/drug effects ; *Staphylococcus aureus/drug effects ; Antimicrobial Peptides/pharmacology/chemistry ; Free Radicals/chemistry/metabolism ; Nanostructures/chemistry ; Microbial Sensitivity Tests ; Anti-Bacterial Agents/pharmacology/chemistry ; Hot Temperature ; Humans ; Anti-Infective Agents/pharmacology/chemistry ; }, abstract = {Chronic refractory wounds caused by multidrug-resistant (MDR) bacterial and biofilm infections are a substantial threat to human health, which presents a persistent challenge in managing clinical wound care. We here synthesized a composite nanosheet AIPH/AMP/MoS2, which can potentially be used for combined therapy because of the photothermal effect induced by MoS2, its ability to deliver antimicrobial peptides, and its ability to generate alkyl free radicals independent of oxygen. The synthesized nanosheets exhibited 61 % near-infrared (NIR) photothermal conversion efficiency, marked photothermal stability and free radical generating ability. The minimal inhibitory concentrations (MICs) of the composite nanosheets against MDR Escherichia coli (MDR E. coli) and MDR Staphylococcus aureus (MDR S. aureus) were approximately 38 μg/mL and 30 μg/mL, respectively. The composite nanosheets (150 μg/mL) effectively ablated >85 % of the bacterial biofilm under 808-nm NIR irradiation for 6 min. In the wound model experiment, approximately 90 % of the wound healed after the 4-day treatment with the composite nanosheets. The hemolysis experiment, mouse embryonic fibroblast (MEFs) cytotoxicity experiment, and mouse wound healing experiment all unveiled the excellent biocompatibility of the composite nanosheets. According to the transcriptome analysis, the composite nanosheets primarily exerted a synergistic therapeutic effect by disrupting the cellular membrane function of S. aureus and inhibiting quorum sensing mediated by the two-component system. Thus, the synthesized composite nanosheets exhibit remarkable antibacterial and biofilm ablation properties and therefore can be used to improve wound healing in chronic biofilm infections.}, }
@article {pmid38899542, year = {2024}, author = {Wu, R and Kong, LX and Liu, F}, title = {Regulation of biofilm gene expression by DNA replication in Bacillus subtilis.}, journal = {Journal of cellular and molecular medicine}, volume = {28}, number = {12}, pages = {e18481}, pmid = {38899542}, issn = {1582-4934}, mesh = {*Biofilms/growth &amp; development ; *Bacillus subtilis/genetics/metabolism/physiology ; *DNA Replication/genetics ; *Gene Expression Regulation, Bacterial ; *Bacterial Proteins/genetics/metabolism ; Extracellular Polymeric Substance Matrix/metabolism ; Cell Cycle/genetics ; }, abstract = {Bacillus subtilis relies on biofilms for survival in harsh environments. Extracellular polymeric substance (EPS) is a crucial component of biofilms, yet the dynamics of EPS production in single cells remain elusive. To unveil the modulation of EPS synthesis, we built a minimal network model comprising the SinI-SinR-SlrR module, Spo0A, and EPS. Stochastic simulations revealed that antagonistic interplay between SinI and SinR enables EPS production in bursts. SlrR widens these bursts and increases their frequency by stabilizing SinR-SlrR complexes and depleting free SinR. DNA replication and chromosomal positioning of key genes dictate pulsatile changes in the slrR:sinR gene dosage ratio (gr) and Spo0A-P levels, each promoting EPS production in distinct phases of the cell cycle. As the cell cycle lengthens with nutrient stress, the duty cycle of gr pulsing decreases, whereas the amplitude of Spo0A-P pulses elevates. This coordinated response facilitates keeping a constant proportion of EPS-secreting cells within colonies across diverse nutrient conditions. Our results suggest that bacteria may 'encode' eps expression through strategic chromosomal organization. This work illuminates how stochastic protein interactions, gene copy number imbalance, and cell-cycle dynamics orchestrate EPS synthesis, offering a deeper understanding of biofilm formation.}, }
@article {pmid38899004, year = {2024}, author = {Akrami, S and Ekrami, A and Avarvand, AY}, title = {Biofilm generation and antibiotic resistant profile of extensive and multidrug resistant Pseudomonas aeruginosa from burn patients in Ahvaz: A cross-sectional study.}, journal = {Health science reports}, volume = {7}, number = {6}, pages = {e2138}, pmid = {38899004}, issn = {2398-8835}, abstract = {BACKGROUND AND AIMS: Multidrug and extensive drug-resistant Pseudomonas aeruginosa was extracted from burn patients referring to burn centers in southwest Iran so that biofilm generation and antibiotic resistance could be investigated.<br><br>METHODS: A specific primer was used to confirm all our considered 110 P. aeruginosa culture-positive reports on 345 burn patients. The resistance of P. aeruginosa to seven antibiotics and Colistin with minimum inhibitory concentration (MIC) was assessed. Biofilm formation was assessed by the phenotypic study of specimens under Congo red agar and microtiter plate assays.<br><br>RESULTS: One hundred and 10 clinical P. aeruginosa isolates taken from burn wound infections were validated. Among P. aeruginosa isolates, Piperacillin, Ceftazidime, Maeropenem, Gentamycin, and Gatifloacin had the highest resistance to antibiotics, while Ticarcillin-Clavulanic acid and Ceftolozane-Tazobactam showed the least resistance. MICs were then evaluated via the E test. Seven isolates were resistant to colistin. Colistin reference MICs for multidrug-resistant P. aeruginosa prevalence was 38%, while it was 22% for extensively drug-resistant (XDR) P. aeruginosa. One P. aeruginosa was pandrug-resistant (PDR). Under Congo red agar test, 66 isolates (67%) formed biofilms and black colonies, whereas 44 isolates (50%) had red colonies. In MTP, 76% formed biofilm. 40%, 32%, 21% of the isolates were strong, moderate, and weak biofilm formers, respectively, while 43% did not form biofilms.<br><br>CONCLUSION: The P. aeruginosa resistance to antimicrobial agents has largely challenged the control of the infection. Accordingly, a higher resistance occurred when the isolates were transferred to the patients. Less than 50% P. aeruginosa samples generated strong biofilms. Consequently, hygienic measurements are essential to inhibit P. aeruginosa transmission to hospitalized patients.}, }
@article {pmid38898117, year = {2024}, author = {Mazurkiewicz, E and Lamch, &#x141; and Wilk, KA and Obłąk, E}, title = {Anti-adhesive, anti-biofilm and fungicidal action of newly synthesized gemini quaternary ammonium salts.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {14110}, pmid = {38898117}, issn = {2045-2322}, support = {2018/31/B/NZ9/03878//National Science Centre, Poland within the OPUS 16 program/ ; }, mesh = {*Biofilms/drug effects ; *Quaternary Ammonium Compounds/pharmacology/chemistry/chemical synthesis ; *Antifungal Agents/pharmacology/chemical synthesis/chemistry ; *Candida albicans/drug effects ; Animals ; Sheep ; Surface-Active Agents/pharmacology/chemical synthesis/chemistry ; Hemolysis/drug effects ; Erythrocytes/drug effects ; Microbial Sensitivity Tests ; Cell Adhesion/drug effects ; Stainless Steel/chemistry ; }, abstract = {Newly synthesized gemini quaternary ammonium salts (QAS) with different counterions (bromide, hydrogen chloride, methylcarbonate, acetate, lactate), chain lengths (C12, C14, C16) and methylene linker (3xCH2) were tested. Dihydrochlorides and dibromides with 12 carbon atoms in hydrophobic chains were characterized by the highest biological activity against planktonic forms of yeast and yeast-like fungi. The tested gemini surfactants also inhibited the production of filaments by C. albicans. Moreover, they reduced the adhesion of C. albicans cells to the surfaces of stainless steel, silicone and glass, and slightly to polystyrene. In particular, the gemini compounds with 16-carbon alkyl chains were most effective against biofilms. It was also found that the tested surfactants were not cytotoxic to yeast cells. Moreover, dimethylcarbonate (2xC12MeCO3G3) did not cause hemolysis of sheep erythrocytes. Dihydrochlorides, dilactate and diacetate showed no mutagenic potential.}, }
@article {pmid38897547, year = {2024}, author = {Liang, J and Zhang, CM and Cao, YX}, title = {Nutrient removal and microbial community succession in moving bed biofilm reactor: Effects of influent carbon to nitrogen ratio fluctuation.}, journal = {Bioresource technology}, volume = {406}, number = {}, pages = {131008}, doi = {10.1016/j.biortech.2024.131008}, pmid = {38897547}, issn = {1873-2976}, mesh = {*Biofilms ; *Nitrogen/metabolism ; *Bioreactors/microbiology ; *Carbon/metabolism ; *Bacteria/metabolism/genetics ; Denitrification ; Phosphorus ; Water Purification/methods ; Nutrients/metabolism ; Biological Oxygen Demand Analysis ; Wastewater/microbiology ; }, abstract = {This study investigated the nutrient removal and microbial community succession in moving bed biofilm reactor under stable and three levels of influent carbon/nitrogen (C/N) ratio fluctuation (± 10%, ± 20%, and ± 30%). Under the conditions of influent C/N ratio fluctuation, the removal efficiency of COD and PO4[3][-]-P decreased 4.7-6.4% and 3.7-12.9%, respectively, while the nitrogen removal was almost unaffected. A sharp decrease in the content of culturable functional bacteria related to nitrogen and phosphorus removal including nitrite-oxidizing bacteria (NOB), aerobic denitrifying bacteria (DNB), and polyphosphate-accumulating organisms (PAOs) from the carrier biofilm was observed. Sequencing analysis revealed that the abundance of Candidatus Competibacter increased 10.3-25.9% and became the dominant genus responsible for denitrification, potentially indicating that nitrate was removed via endogenous denitrification under the influent C/N ratio fluctuation. The above results will provide basic data for the nutrient removal in decentralized wastewater treatment under highly variable influent conditions.}, }
@article {pmid38897501, year = {2024}, author = {Zhang, B and Lan, W and Yan, P and Xie, J}, title = {The antibacterial and inhibition effect of chitosan grafted gentisate acid derivatives against Pseudomonas fluorescens: Attacking multiple targets on structure, metabolism system, antioxidant system, and biofilm.}, journal = {International journal of biological macromolecules}, volume = {273}, number = {Pt 2}, pages = {133225}, doi = {10.1016/j.ijbiomac.2024.133225}, pmid = {38897501}, issn = {1879-0003}, mesh = {*Pseudomonas fluorescens/drug effects ; *Biofilms/drug effects/growth &amp; development ; *Chitosan/pharmacology/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Antioxidants/pharmacology/chemistry ; *Microbial Sensitivity Tests ; *Gentisates/pharmacology/chemistry ; }, abstract = {This work aimed to investigate the antibacterial ability and potential mechanism of chitosan grafted gentisate acid derivatives (CS-g-GA) against Pseudomonas fluorescens. The results showed that CS-g-GA had a significant suppressive impact on the growth of Pseudomonas fluorescens, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were 0.64 mg/mL and 1.28 mg/mL, respectively. Results of scanning electron microscopy (SEM) and alkaline phosphatase (AKPase) confirmed that CS-g-GA destroyed the cell structure thereby causing the leakage of intracellular components. In addition, 1 × MIC of CS-g-GA could significantly inhibit the formation of biofilms, and 74.78 % mature biofilm and 86.21 % extracellular polysaccharide of Pseudomonas fluorescens were eradicated by CS-g-GA at 2 × MIC. The results on the respiratory energy metabolism system and antioxidant system demonstrated that CS-g-GA caused respiratory disturbance and energy limitation by influencing the key enzyme activities. It could also bind to DNA and affect genetic metabolism. From this, it could be seen that CS-g-GA had the potential to control foodborne contamination of Pseudomonas fluorescens by attacking multiple targets.}, }
@article {pmid38897361, year = {2024}, author = {Carrica, MDC and Gorgojo, JP and Alvarez-Hayes, J and Valdez, HA and Lamberti, YA and Rodriguez, ME}, title = {BPP0974 is a Bordetella parapertussis adhesin expressed in the avirulent phase, implicated in biofilm formation and intracellular survival.}, journal = {Microbial pathogenesis}, volume = {193}, number = {}, pages = {106754}, doi = {10.1016/j.micpath.2024.106754}, pmid = {38897361}, issn = {1096-1208}, mesh = {*Biofilms/growth &amp; development ; *Adhesins, Bacterial/genetics/metabolism ; *Bordetella parapertussis/genetics/metabolism ; Humans ; *Bacterial Adhesion ; *Epithelial Cells/microbiology ; Microbial Viability ; Whooping Cough/microbiology ; Gene Expression Regulation, Bacterial ; Cell Line ; }, abstract = {B. parapertussis is a bacterium that causes whooping cough, a severe respiratory infection disease, that has shown an increased incidence in the population. Upon transmission through aerosol droplets, the initial steps of host colonization critically depend on the bacterial adhesins. We here described BPP0974, a B. parapertussis protein that exhibits the typical domain architecture of the large repetitive RTX adhesin family. BPP0974 was found to be retained in the bacterial membrane and secreted into the culture medium. This protein was found overexpressed in the avirulent phase of B. parapertussis, the phenotype proposed for initial host colonization. Interestingly, BPP0974 was found relevant for the biofilm formation as well as involved in the bacterial attachment to and survival within the respiratory epithelial cells. Taken together, our results suggest a role for BPP0974 in the early host colonization and pathogenesis of B. parapertussis.}, }
@article {pmid38897118, year = {2024}, author = {Pereira, AR and Gomes, IB}, title = {The effects of methylparaben exposure on biofilm tolerance to chlorine disinfection.}, journal = {Journal of hazardous materials}, volume = {476}, number = {}, pages = {134883}, doi = {10.1016/j.jhazmat.2024.134883}, pmid = {38897118}, issn = {1873-3336}, mesh = {*Biofilms/drug effects ; *Parabens/toxicity ; *Chlorine/pharmacology ; *Disinfection/methods ; *Disinfectants/pharmacology/toxicity ; Acinetobacter calcoaceticus/drug effects ; Stenotrophomonas maltophilia/drug effects ; Polypropylenes ; Polyethylene ; Anti-Bacterial Agents/pharmacology/toxicity ; Water Purification/methods ; Water Pollutants, Chemical/toxicity ; }, abstract = {Parabens are emerging contaminants that have been detected in drinking water. Their presence in DW distribution systems (DWDS) can alter bacterial behaviour, characteristics, and structure, which may compromise DW disinfection. This work provides insights into the impact of methylparaben (MP) on the tolerance to chlorine disinfection and antibiotics from dual-species biofilms formed by Acinetobacter calcoaceticus and Stenotrophomonas maltophilia isolated from DW and grown on high-density polyethylene (HDPE) and polypropylene (PPL). Results showed that dual-species biofilms grown on PPL were more tolerant to chlorine disinfection, expressing a decrease of over 50 % in logarithmic reduction values of culturable cells in relation to non-exposed biofilms. However, bacterial tolerance to antibiotics was not affected by MP presence. Although MP-exposed dual-species biofilms grown on HDPE and PPL were metabolically more active than non-exposed counterparts, HDPE seems to be the material with lower impact on DW risk management and disinfection, if MP is present. Overall, results suggest that MP presence in DW may compromise chlorine disinfection, and consequently affect DW quality and stability, raising potential public health issues.}, }
@article {pmid38896886, year = {2024}, author = {Yan, P and Zhuang, S and Li, M and Zhang, J and Wu, S and Xie, H and Wu, H}, title = {Combined environmental pressure induces unique assembly patterns of micro-plastisphere biofilm microbial communities in constructed wetlands.}, journal = {Water research}, volume = {260}, number = {}, pages = {121958}, doi = {10.1016/j.watres.2024.121958}, pmid = {38896886}, issn = {1879-2448}, mesh = {*Wetlands ; *Biofilms ; Microbiota ; Wastewater/microbiology ; Humic Substances ; Sulfamethoxazole ; Microplastics ; }, abstract = {The characteristics and dynamics of micro-plastisphere biofilm on the surface of microplastics (MPs) within artificial ecosystems, such as constructed wetlands (CWs), remain unclear, despite these ecosystems' potential to serve as sinks for MPs. This study investigates the dynamic evolution of micro-plastisphere biofilm in CWs, utilizing simulated wastewater containing sulfamethoxazole and humic acid, through physicochemical characterization and metagenomic analysis. Two different types of commercial plastics, including non-degradable polyethylene and degradable polylactic acid, were shredded into MPs and studied. The findings reveal that the types, shape and incubation time of MPs, along with humic acid content in wastewater, affected the quantity and quality of biofilms, such as the biofilm composition, spatial structure and microbial communities. After just 15 days into incubation, numerous microbials were observed on MP samples, with increases in biofilms content and enhanced humification of extracellular polymeric substances over time. Additionally, microbial communities on polylactic acid MPs, or those incubated for longer time, exhibit higher diversity, connectivity and stability, along with reduced vulnerability. Conversely, biofilms on polyethylene MPs were thicker, with higher potential for greenhouse gas emission and increased risk of antibiotic resistance genes. The addition of humic acid demonstrated opposite effects on biofilms across environmental interfaces, possibly due to its dual potential to produce light-induced free radicals and serve as a carbon source. Binning analysis further uncovered a unique assembly pattern of nutrients cycle genes and antibiotic resistance genes, significantly correlated within micro-plastisphere microbial communities, under the combined stress of nutrition and sulfamethoxazole. These results emphasize the shaping of micro-plastisphere biofilm characteristics by unique environmental conditions in artificial ecosystems, and the need to understand how DOM and other pollutants covary with MP pollution.}, }
@article {pmid38896257, year = {2024}, author = {Li, X and Lin, S and Wang, Y and Chen, Y and Zhang, W and Shu, G and Li, H and Xu, F and Lin, J and Peng, G and Fu, H}, title = {Application of biofilm dispersion-based nanoparticles in cutting off reinfection.}, journal = {Applied microbiology and biotechnology}, volume = {108}, number = {1}, pages = {386}, pmid = {38896257}, issn = {1432-0614}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Nanoparticles/chemistry ; *Anti-Bacterial Agents/pharmacology ; Humans ; Bacteria/drug effects ; Bacterial Infections/prevention &amp; control/drug therapy/microbiology ; Reinfection/prevention &amp; control ; Extracellular Polymeric Substance Matrix/metabolism/chemistry/drug effects ; }, abstract = {Bacterial biofilms commonly cause chronic and persistent infections in humans. Bacterial biofilms consist of an inner layer of bacteria and an autocrine extracellular polymeric substance (EPS). Biofilm dispersants (abbreviated as dispersants) have proven effective in removing the bacterial physical protection barrier EPS. Dispersants are generally weak or have no bactericidal effect. Bacteria dispersed from within biofilms (abbreviated as dispersed bacteria) may be more invasive, adhesive, and motile than planktonic bacteria, characteristics that increase the probability that dispersed bacteria will recolonize and cause reinfection. The dispersants should be combined with antimicrobials to avoid the risk of severe reinfection. Dispersant-based nanoparticles have the advantage of specific release and intense penetration, providing the prerequisite for further antibacterial agent efficacy and achieving the eradication of biofilms. Dispersant-based nanoparticles delivered antimicrobial agents for the treatment of diseases associated with bacterial biofilm infections are expected to be an effective measure to prevent reinfection caused by dispersed bacteria. KEY POINTS: • Dispersed bacteria harm and the dispersant's dispersion mechanisms are discussed. • The advantages of dispersant-based nanoparticles in bacteria biofilms are discussed. • Dispersant-based nanoparticles for cutting off reinfection in vivo are highlighted.}, }
@article {pmid38895145, year = {2024}, author = {Xu, Y and Hao, Y and Arif, M and Xing, X and Deng, X and Wang, D and Meng, Y and Wang, S and Hasanin, MS and Wang, W and Zhou, Q}, title = {Poly(Lysine)-Derived Carbon Quantum Dots Conquer Enterococcus faecalis Biofilm-Induced Persistent Endodontic Infections.}, journal = {International journal of nanomedicine}, volume = {19}, number = {}, pages = {5879-5893}, pmid = {38895145}, issn = {1178-2013}, mesh = {*Enterococcus faecalis/drug effects/physiology ; *Quantum Dots/chemistry ; *Biofilms/drug effects ; *Polylysine/chemistry/pharmacology ; *Carbon/chemistry/pharmacology ; Animals ; *Gram-Positive Bacterial Infections/drug therapy/microbiology ; Anti-Bacterial Agents/pharmacology/chemistry ; Humans ; Reactive Oxygen Species/metabolism ; Mice ; }, abstract = {INTRODUCTION: Persistent endodontic infections (PEIs) mediated by bacterial biofilm mainly cause persistent periapical inflammation, resulting in recurrent periapical abscesses and progressive bone destruction. However, conventional root canal disinfectants are highly damaging to the tooth and periodontal tissue and ineffective in treating persistent root canal infections. Antimicrobial materials that are biocompatible with apical tissues and can eliminate PEIs-associated bacteria are urgently needed.<br><br>METHODS: Here, &#x3b5;-poly (L-lysine) derived carbon quantum dots (PL-CQDs) are fabricated using pyrolysis to remove PEIs-associated bacterial biofilms.<br><br>RESULTS: Due to their ultra-small size, high positive charge, and active reactive oxygen species (ROS) generation capacity, PL-CQDs exhibit highly effective antibacterial activity against Enterococcus faecalis (E. faecalis), which is greatly dependent on PL-CQDs concentrations. 100 &#xb5;g/mL PL-CQDs could kill E. faecalis in 5 min. Importantly, PL-CQDs effectively achieved a reduction of biofilms in the isolated teeth model, disrupting the dense structure of biofilms. PL-CQDs have acceptable cytocompatibility and hemocompatibility in vitro and good biosafety in vivo.<br><br>DISCUSSION: Thus, PL-CQDs provide a new strategy for treating E. faecalis-associated PEIs.}, }
@article {pmid38894900, year = {2024}, author = {Liu, P and Wang, L and Song, Y and Pei, H and Cao, X}, title = {Virtual Screening of Inhibitors of Streptococcus mutans Biofilm from Lonicera japonica flos and Activity Validation.}, journal = {ACS medicinal chemistry letters}, volume = {15}, number = {6}, pages = {781-790}, pmid = {38894900}, issn = {1948-5875}, abstract = {In this study, potential inhibitors of Streptococcus mutans biofilm were screened from Lonicera japonica flos using semiflexible molecular docking. A total of 88 metabolites from L. japonica flos and 14 biofilm-related proteins of S. mutans were analyzed, and 25 compounds were initially screened out. Subsequently, 9 compounds with higher availability were subjected to experimental validation, confirming that 6 of them effectively inhibit the S. mutans biofilm formation. Notably, chlorogenic acid was found to potentially disrupt the GbpC protein, which plays a role in the sucrose-dependent adhesion pathway. Similarly, oleanolic acid appeared to impede the adhesin P1 protein involved in the sucrose-independent adhesion mechanism, corroborating the computational predictions. The results of this study provide essential insights for leveraging L. japonica flos in the creation of dental-care-related products and food items aimed at oral health.}, }
@article {pmid38892010, year = {2024}, author = {Hu, H}, title = {Molecular Mechanisms of Biofilm Infections and Combat Strategies.}, journal = {International journal of molecular sciences}, volume = {25}, number = {11}, pages = {}, pmid = {38892010}, issn = {1422-0067}, mesh = {*Biofilms/growth &amp; development ; Humans ; Bacterial Infections/microbiology ; Bacteria/genetics/metabolism ; }, abstract = {Microbial biofilms are the most important drivers of chronic and recurrent infections [...].}, }
@article {pmid38890583, year = {2024}, author = {Ozturk, B and Akkaya, H and Aglar, E and Saracoglu, O}, title = {Effect of preharvest biofilm application regimes on cracking and fruit quality traits in '0900 Ziraat' sweet cherry cultivar.}, journal = {BMC plant biology}, volume = {24}, number = {1}, pages = {574}, pmid = {38890583}, issn = {1471-2229}, mesh = {*Fruit/microbiology/physiology ; *Biofilms/drug effects ; *Prunus avium/physiology/drug effects ; Ascorbic Acid/metabolism ; }, abstract = {BACKGROUND: Fruit cracking impacts the quality of sweet cherry, significantly affecting its marketability due to increased susceptibility to injury, aesthetic flaws, and susceptibility to pathogens. The effect of 1% biofilm (Parka™) application regimes on fruit cracking and other quality parameters in the '0900 Ziraat' cherry cultivar was investigated in this study. Fruit sprayed with water were served as control (U1). Fruit treated only once with biofilm three, two and one week before the commercial harvest were considered as U2, U3 and U4, respectively. Fruit treated with biofilm three, two, and one week before harvest were considered as U5; three and two week before harvest as U6; two and one week before harvest as U7; and fruit treated three and one week before harvest as U8.<br><br>RESULTS: In both measurement periods, the lower cracking index was obtained in biofilm-treated sweet cherry fruit. However, the firmness of biofilm-treated fruit was higher than that of the control fruit. The lowest respiration rate was observed in U7, while the highest weight was recorded in U4 and U5 than the control. The biofilm application decreased fruit coloration. The biofilm application also increased the soluble solids content of the fruit. The U2, U3 and U4 applications at harvest showed higher titratable acidity than the control. In both measurement periods, the vitamin C content of the U2, U5, U6, U7 and U8 applications was found to be higher than that of the control. The total monomeric anthocyanin of the U3 and U8 applications was higher than that of the control. Furthermore, the antioxidant activity of the U2, U3 and U5 in the DPPH, and the U7 and U8 in FRAP were measured higher thanthat of the control.<br><br>CONCLUSIONS: The application of biofilms has the potential to mitigate fruit cracking, prolong postharvest life of sweet cherries, and enhance fruit firmness.}, }
@article {pmid38889807, year = {2024}, author = {Seta, JF and Pawlitz, PR and Aboona, F and Weaver, MJ and Bou-Akl, T and Ren, W and Markel, DC}, title = {Efficacy of Commercially Available Irrigation Solutions on Removal of Staphylococcus Aureus and Biofilm From Porous Titanium Implants: An In Vitro Study.}, journal = {The Journal of arthroplasty}, volume = {39}, number = {9S1}, pages = {S292-S298}, doi = {10.1016/j.arth.2024.06.024}, pmid = {38889807}, issn = {1532-8406}, mesh = {*Biofilms/drug effects ; *Titanium ; *Staphylococcus aureus/drug effects/physiology ; *Prosthesis-Related Infections/prevention &amp; control/microbiology ; *Therapeutic Irrigation/methods ; Porosity ; Anti-Bacterial Agents/pharmacology ; Humans ; Staphylococcal Infections/prevention &amp; control/microbiology ; Microscopy, Electron, Scanning ; In Vitro Techniques ; Prostheses and Implants/microbiology ; }, abstract = {BACKGROUND: Periprosthetic joint infection remains a major problem. The bactericidal efficacy of commercial irrigation solutions for the treatment of infection is not well established in the presence of porous titanium (Ti) implants. This study compared the in vitro efficacy of five irrigation solutions on infected three-dimensional-printed porous Ti discs.<br><br>METHODS: Titanium discs (2&#xa0;&#xd7; 4 mm, 400, 700, and 1,000 &#x3bc;m) were infected with S.&#xa0;aureus (1&#xa0;&#xd7; 10[6] colony-forming unit/mL) and incubated for 3&#xa0;hours or 3 days to create acute or chronic infection with biofilm. Discs were irrigated with saline, antibiotic, or antiseptic solutions, then repeatedly sonicated. Sonicates were cultured for bacterial quantification. Statistical analyses were performed using one-way analysis of variance (ANOVA), followed by Tukey-Kramer post hoc testing (P < .05 significance). Biofilms were visualized by scanning electron microscopy.<br><br>RESULTS: Saline irrigation was ineffective in both groups. In acute infections with 400 &#x3bc;m pores, differences were found with saline versus solution #3 (P&#xa0;= .015) and #4 (P&#xa0;= .015). Solution #4 had the lowest bacterial counts for all pore sizes. For biofilm, irrigation with saline, solutions #1, #2, and #3 inadequately cleared bacteria in all pore sizes. Lower remaining concentrations were observed in #4 with 400&#x3bc;m pores compared to saline (P&#xa0;= .06) and #2 (P&#xa0;= .039). The scanning electron microscopy showed a reduction of biofilm in samples washed with #4.<br><br>CONCLUSIONS: Irrigation of infected porous Ti discs with saline, solutions #1 and #2 failed to reduce the bacterial load. The 400 &#x3bc;m discs consistently had more bacteria despite irrigation, highlighting the difficulty of removing bacteria from small pores. Solutions #3 and #4 reduced bacteria acutely, but only #4 demonstrated efficacy in clearing biofilm compared to saline. These results should be considered when treating periprosthetic joint infection in the presence of porous components and the potential presence of biofilm.}, }
@article {pmid38888425, year = {2024}, author = {Suriyanarayanan, T and Lee, LS and Han, SHY and Ching, J and Seneviratne, CJ}, title = {Targeted metabolomics analysis approach to unravel the biofilm formation pathways of Enterococcus faecalis clinical isolates.}, journal = {International endodontic journal}, volume = {57}, number = {10}, pages = {1505-1520}, doi = {10.1111/iej.14110}, pmid = {38888425}, issn = {1365-2591}, support = {AM/SU047/2020 (SRDUKAMR2047)//Duke-NUS Medical School/ ; }, mesh = {*Biofilms/drug effects ; *Enterococcus faecalis/metabolism ; *Metabolomics ; Humans ; Microbial Sensitivity Tests ; }, abstract = {AIM: (i) To characterize Enterococcus faecalis biofilm formation pathways by semi-targeted metabolomics and targeted nitrogen panel analysis of strong (Ef63) and weak (Ef 64) biofilm forming E. faecalis clinical isolates and (ii) to validate the identified metabolic markers using targeted inhibitors.<br><br>METHODOLOGY: Previous proteomics profiling of E.&#x2009;faecalis clinical isolates with strong and weak biofilm formation revealed that differences in metabolic activity levels of small molecule, nucleotide and nitrogen compound metabolic processes and biosynthetic pathways, cofactor metabolic process, cellular amino acid and derivative metabolic process and lyase activity were associated with differences in biofilm formation. Hence, semi-targeted analysis of Ef 63, Ef 64 and ATC control strain Ef 29212 was performed by selecting metabolites that were part of both the previously identified pathways and a curated library with confirmed physical and chemical identity, followed by confirmatory targeted nitrogen panel analysis. Significantly regulated metabolites (p&#x2009;<&#x2009;.05) were selected based on fold change cut-offs of 1.2 and 0.8 for upregulation and downregulation, respectively, and subjected to pathway enrichment analysis. The identified metabolites and pathways were validated by minimum biofilm inhibitory concentration (MBIC) and colony forming unit (CFU) assays with targeted inhibitors.<br><br>RESULTS: Metabolomics analysis showed upregulation of betaine, hypoxanthine, glycerophosphorylcholine, tyrosine, inosine, allantoin and citrulline in Ef 63 w.r.t Ef 64 and Ef 29212, and thesemetabolites mapped to purinemetabolism, urea cycle and aspartate metabolism pathways. MBIC and CFU assays using compounds against selected metabolites and metabolic pathways, namely glutathione against hypoxanthine and hydroxylamine against aspartate metabolism showed inhibitory effects against E.&#x2009;faecalis biofilm formation.<br><br>CONCLUSIONS: The study demonstrated the importance of oxidative stress inducers such as hypoxanthine and aspartate metabolism pathway in E.&#x2009;faecalis biofilm formation. Targeted therapeutics against these metabolic markers can reduce the healthcare burden associated with E.&#x2009;faecalis infections.}, }
@article {pmid38887762, year = {2024}, author = {Alvarado-Gutiérrez, ML and Ruiz-Ordaz, N and Galíndez-Mayer, J and Santoyo-Tepole, F and García-Mena, J and Nirmalkar, K and Curiel-Quesada, E}, title = {Dynamic and structural response of a multispecies biofilm to environmental perturbations induced by the continuous increase of benzimidazole fungicides in a permeable reactive biobarrier.}, journal = {Journal of environmental health science &amp; engineering}, volume = {22}, number = {1}, pages = {329-344}, pmid = {38887762}, issn = {2052-336X}, abstract = {PURPOSE: This work explores the dynamics of spatiotemporal changes in the taxonomic structure of biofilms and the degradation kinetics of three imidazole group compounds: carbendazim (CBZ), methyl thiophanate (MT), and benomyl (BN) by a multispecies microbial community attached to a fixed bed horizontal tubular reactor (HTR). This bioreactor mimics a permeable reactive biobarrier, which helps prevent the contamination of water bodies by pesticides in agricultural wastewater.<br><br>METHODS: To rapidly quantify the microbial response to crescent loading rates of benzimidazole compounds, a gradient system was used to transiently raise the fungicide volumetric loading rates, measuring the structural and functional dynamics response of a microbial community in terms of the volumetric removal rates of the HTR entering pollutants.<br><br>RESULTS: The loading rate gradient of benzimidazole compounds severely impacts the spatiotemporal taxonomic structure of the HTR biofilm-forming microbial community. Notable differences with the original structure in HTR stable conditions can be noted after three historical contingencies (CBZ, MT, and BN gradient loading rates). It was evidenced that the microbial community did not return to the composition prior to environmental disturbances; however, the functional similarity of microbial communities after steady state reestablishment was observed.<br><br>CONCLUSIONS: The usefulness of the method of gradual delivery of potentially toxic agents for a microbial community immobilized in a tubular biofilm reactor was shown since its functional and structural dynamics were quickly evaluated in response to fungicide composition and concentration changes. The rapid adjustment of the contaminants' removal rates indicates that even with changes in the taxonomic structure of a microbial community, its functional redundancy favors its adjustment to gradual environmental disturbances.}, }
@article {pmid38886629, year = {2024}, author = {Kakian, F and Arasteh, N and Mirzaei, E and Motamedifar, M}, title = {Study of MIC of silver and zinc oxide nanoparticles, strong and cost-effective antibacterial against biofilm-producing Acinetobacter baumannii in Shiraz, Southwest of Iran.}, journal = {BMC infectious diseases}, volume = {24}, number = {1}, pages = {593}, pmid = {38886629}, issn = {1471-2334}, mesh = {*Acinetobacter baumannii/drug effects/genetics ; *Biofilms/drug effects ; Iran ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology ; *Silver/pharmacology ; *Zinc Oxide/pharmacology/chemistry ; Humans ; *Acinetobacter Infections/microbiology ; *Metal Nanoparticles/chemistry ; *Drug Resistance, Multiple, Bacterial ; Adult ; Male ; Female ; Middle Aged ; Adolescent ; Young Adult ; Child ; Aged ; Child, Preschool ; Nanoparticles/chemistry ; }, abstract = {BACKGROUND: Acinetobacter baumannii resistant strains lead to increased mortality, treatment costs, and an increase in the length of hospitalization. Nowadays, nanoparticles are considered a substitute for antibiotics. This study aimed to determine the MIC of Silver (Ag) and Zinc Oxide (ZnO) Nanoparticles (NPs) on Biofilm-Producing Acinetobacter baumannii and determine the relationship between MIC and frequency of efflux pump genes in cutaneous specimens in Shiraz, Southwest Iran in 2021-2022.<br><br>METHODS: In this study, specimens were collected from April 2021 to June 2022 at Namazi and Faqihi Hospitals in Shiraz. Investigation of biofilm production in multidrug resistance (MDR) isolates was done by the microtiter plate method. Synthesized nanoparticles were characterized by UV-vis spectrum, X-ray diffraction (XRD), and electron microscopy. The MIC of AgNPs and ZnONPs for isolates was done using the method described in the CLSI guideline (2018). The antibacterial effect of MIC of NPs on inanimate objects was done by colony counts. The prevalence of efflux pump genes (adeR, adeC, adeA, abeM, adeK, adeI) was also investigated by PCR technique.<br><br>RESULTS: The highest ceftriaxone resistance (68%) and lowest colistin resistance (7%) were identified. 57% of isolates were MDR. In addition, 71.9% could produce biofilm and 28.1% of isolates could not produce biofilm. The average size of AgNPs and ZnONPs in the present study is 48 and <&#x2009;70&#xa0;nm, respectively. The nanoparticles were spherical. The MIC and the MBC of the ZnONPs were in the range of 125 to 250&#xa0;&#xb5;g/mL respectively. Also, for AgNPs, the MIC and the MBC were in the range of 62.5 to 250&#xa0;&#xb5;g/ml, respectively. AbeM gene had the highest frequency and the AdeK gene had the lowest frequency. Statistical analysis showed that there is a relationship between the frequency of adeA, adeC, and adeM genes with the MIC of AgNPs and ZnONPs.<br><br>CONCLUSION: According to the results of the present study, inanimate objects such as scalpels in contact with AgNPs (6000&#xa0;&#xb5;g/ml for 240&#xa0;min) or ZnONPs (5000&#xa0;&#xb5;g/ml for 120&#xa0;min) can be free of biofilm producing Acinetobacter baumannii &#xa0;with efflux pump genes.}, }
@article {pmid38886442, year = {2024}, author = {Shen, DS and Xing, XJ and Long, YY and Hui, C}, title = {[Applications of biofilm in environmental pollution control and the related challenges].}, journal = {Ying yong sheng tai xue bao = The journal of applied ecology}, volume = {35}, number = {5}, pages = {1426-1434}, doi = {10.13287/j.1001-9332.202405.028}, pmid = {38886442}, issn = {1001-9332}, mesh = {*Biofilms/growth &amp; development ; *Environmental Pollution/prevention &amp; control ; *Metals, Heavy ; *Biodegradation, Environmental ; Environmental Pollutants ; Organic Chemicals ; }, abstract = {Biofilm has been used in environmental pollution control in recent years due to its characteristics of adsorption and biodegradation. Beyond the success of its utilization in wastewater treatment, biofilm technique has high application value in the remediation of heavy metals and organic pollutants in soils. With the extensive attention and research of emerging pollutants such as microplastics and antibiotic resistance genes (ARGs), the pivotal role of biofilm can not be overlooked. Here, we presented a comprehensive review of the structure, formation mecha-nism, population, and functional aspects of biofilm, as well as its applications and mechanisms in environmental pollution control in recent years. We emphatically discussed the removal mechanism and application progress of biofilm on heavy metals and organic pollutants. We further expounded some novel environmental challenges posed by biofilm under new circumstances, including the coexistence of various pollutants in plastisphere, the spread of ARGs, and the accumulation of pathogens. Finally, we put forward the gaps of current research and prospects for future research, especially the importance of exploring the interaction relationship and mechanism between biofilm and various pollutants. It is expected to provide theoretical basis for the development of new technology of biofilm remediation.}, }
@article {pmid38883710, year = {2024}, author = {Muturi, P and Wachira, P and Wagacha, M and Mbae, C and Kavai, S and Mugo, M and Muhammed, M and González, JF and Kariuki, S and Gunn, JS}, title = {Salmonella Typhi Haplotype 58 (H58) Biofilm Formation and Genetic Variation in Typhoid Fever Patients with Gallstones in an Endemic Setting in Kenya.}, journal = {medRxiv : the preprint server for health sciences}, volume = {}, number = {}, pages = {}, pmid = {38883710}, support = {R01 AI099525/AI/NIAID NIH HHS/United States ; R01 AI116917/AI/NIAID NIH HHS/United States ; }, abstract = {The causative agent of typhoid fever, Salmonella enterica serovar Typhi, is a human restricted pathogen. Human carriers, 90% of whom have gallstones in their gallbladder, continue to shed the pathogen after treatment. The genetic mechanisms involved in establishing the carrier state are poorly understood, but S. Typhi is thought to undergo specific genetic changes within the gallbladder as an adaptive mechanism. In the current study, we aimed to identify biofilm forming ability and the genetic differences in longitudinal clinical S. Typhi isolates from asymptomatic carriers with gallstones in Nairobi, Kenya. Whole genome sequences were analyzed from 22 S. Typhi isolates, 20 from stool and 2 from blood samples, all genotype 4.3.1 (H58). Nineteen strains were from four patients also diagnosed with gallstones, of whom, three had typhoid symptoms and continued to shed S. Typhi after treatment. All isolates had point mutations in the quinolone resistance determining region (QRDR) and only sub-lineage 4.3.1.2EA3 encoded multidrug resistance genes. There was no variation in antimicrobial resistance patterns among strains from the same patient/household. Non-multidrug resistant (MDR), isolates formed significantly stronger biofilms in vitro than the MDR isolates, p<0.001. A point mutation within the treB gene (treB A383T) was observed in strains isolated after clinical resolution from patients living in 75% of the households. Missense mutations in Vi capsular polysaccharide genes, tviE P263S was also observed in 18% of the isolates. This study provides insights into the role of typhoid carriage, biofilm formation, AMR genes and genetic variations in S. Typhi from asymptomatic carriers.}, }
@article {pmid38882878, year = {2024}, author = {Peeran, SW and Murugan, M and Doggalli, N and Fageeh, H and Ibrahim, W and Al-Ak'hali, MS and Basheer, SN}, title = {Herbal Composite Preparation and Investigating its Efficiency to Inhibit Biofilm Formation and Virulence Factors of Prevotella Intermedia and Porphyromonas Gingivalis - Formulation of Mouthwash Using a Herbal Composite and Evaluating its Anti-microbial Activity.}, journal = {Journal of pharmacy &amp; bioallied sciences}, volume = {16}, number = {Suppl 2}, pages = {S1574-S1584}, pmid = {38882878}, issn = {0976-4879}, abstract = {Herbal composite preparation was studied with the aim of inhibiting the virulence factors of two dental pathogens: Prevotella intermedia and Porphyromonas gingivalis. A novel herbal composite was developed using the herbal extracts of Wrightia tinctoria and Bauhinia variegata. During the study, the following observations were noted. The minimal inhibitory concentration of Wrightia tinctoria and Bauhinia variegata composites (WBc) was obtained for the test concentration of 20 μg/ml (16 ± 0.57 mm and 15 ± 0.75 mm of inhibitory zones against Prevotella intermedia and Porphyromonas gingivalis, respectively). Biofilm inhibition assay results revealed about 0.51 ± 1.25 mg/ml and 0.53 ± 0.57 mg/ml of minimal biofilm eradication concentration (MBEC) against Prevotella intermedia and Porphyromonas gingivalis, respectively. The effect of WBc on lactic acid production showed that 200 μg/ml and 400 μg/ml concentrates reduced up to 80% and 70% in Prevotella intermedia and Porphyromonas gingivalis, respectively. Formulated herbal mouthwash showed good stability under all three different test conditions (5°C, 25°C, and 40°C) as the color, odor, phase separation, and homogeneity were not changed for the period of 3 months. The anti-bacterial activity of formulated mouthwash (30 μg/ml) exhibited maximum inhibitory zones of about 18 ± 0.75 mm and 19 ± 1.05 mm against the respective test bacteria - Prevotella intermedia and Porphyromonas gingivalis. Amplification of mfa1 and clpB genes showed 246 bp and 294 bp fragments of P. gingivalis and 238 bp and 280 bp fragments of P. intermedia during agarose electrophoretic analysis. The docking report revealed -5.84 Kcal/Mol binding energy and found three hydrogen bonding between the quercetin and target protein, mfa1 of Porphyromonas gingivalis. The target protein, clpB of Prevotella intermedia, and quercetin had -6.72 Kcal/Mol binding energy and found four hydrogen bonds between them. The developed composite could be optimized in future to develop a novel and biocompatible herbal mouthwash for the prevention of different dental caries and gingival inflammation associated with dental biofilm formation.}, }
@article {pmid38882794, year = {2024}, author = {Adhikary, T and Panda, A and Mishra, P and Kumar, H and Bhuyan, L and Behera, SS and Nivedita, S}, title = {Unveiling the In Vitro Anti-Biofilm Potential of Lactobacillus rhamnosus Against Saliva-Based Pathogens: A Gender-Age-Area Specific Study.}, journal = {Journal of pharmacy &amp; bioallied sciences}, volume = {16}, number = {Suppl 2}, pages = {S1764-S1770}, pmid = {38882794}, issn = {0976-4879}, abstract = {Probiotics, like lactobacilli and bifidobacteria, benefit health by populating the digestive system, which houses numerous microbial species. Studies demonstrate their ability to inhibit biofilm formation, crucial in preventing oral conditions like dental caries. Our research evaluated a probiotic strain's anti-biofilm efficacy against oral pathogens in 45 individuals' saliva, alongside its biofilm-forming potential. Analysis revealed significant biofilm inhibition in 36 samples. Comparisons based on age, gender, and geography further supported these findings. We propose further exploration of probiotics tailored to specific demographics to enhance oral health outcomes, suggesting a promising avenue for preventing oral microbial diseases.}, }
@article {pmid38882733, year = {2024}, author = {Jayakumar, S and Sridhar, D and John, BM and Arumugam, K and Ponnusamy, P and Pulidindi, H}, title = {Biofilm in Endodontic Infection and its Advanced Therapeutic Options - An Updated Review.}, journal = {Journal of pharmacy &amp; bioallied sciences}, volume = {16}, number = {Suppl 2}, pages = {S1104-S1109}, pmid = {38882733}, issn = {0976-4879}, abstract = {Pulpal and periapical pathosis are biofilm-induced infections. Understanding the complex nature of endodontic biofilm would help to create a new disinfection strategy to eliminate the microorganism from the root canal system. The intricate canal structure creates challenges for proper disinfection, necessitating the need to understand the biofilm structure, composition, and mechanism within the biofilm community. This paper describes the endodontic biofilm structure, formation of biofilm, and advanced therapeutic options for combating the biofilm community within the root canal system.}, }
@article {pmid38882294, year = {2024}, author = {Mahendrarajan, V and Lazarus, H and Easwaran, N}, title = {Quorum quenching mediated biofilm impediment in Chromobacterium violaceum and Staphylococcus aureus by leaf extracts of Delonix elata.}, journal = {Heliyon}, volume = {10}, number = {11}, pages = {e31898}, pmid = {38882294}, issn = {2405-8440}, abstract = {Biofilms are complex communities of microorganisms that cause systemic infections, resistance development and delay in healing wounds. Biofilms can form in various parts of the human body, such as the teeth, lungs, urinary tract, and wounds. Biofilm complicates the effects of antibiotics in treating infections. In search of a cure, a plant-based phyto component was selected for this investigation as an anti-quorum-mediated biofilm restricting agent in Gram-negative Chromobacterium violaceum and Gram-positive Staphylococcus aureus. The bioactive components in Delonix elata (DE) ethyl acetate extract were identified using Gas chromatography and mass spectrometry. The extract was examined for toxicity using 3T3 cell lines and brine shrimp and ascertained to be non-toxic. Violacein was inhibited up to 68.81 % in C. violaceum at 0.6 mg/ml concentration. Hemolysin synthesis impediments in C. violaceum and S. aureus were 80 % and 51.35 %, respectively, at 0.6 mg/ml of DE extract. At 0.6 mg/ml, EPS was abated by up to 49 % in C. violaceum and 35.26 % in S. aureus. DE extract prevented biofilm formation in C. violaceum and S. aureus up to 76.45 % and 58.15 %, respectively, while associated eDNA was suppressed up to 67.50 % and 53.47 % at the respective sub-MIC concentrations. Expression of genes such as cviI, cviR, vioA, vioB, and vioE were dramatically reduced in C. violaceum, while genes such as agrA, sarA, fnbA, and fnbB were significantly reduced in S. aureus. Docking demonstrates that two or more DE molecules bind efficiently to the QS receptors of C. violaceum and S. aureus. Thus, DE extract can be investigated for therapeutic purposes against pathogenic microorganisms by rendering them less virulent through quorum quenching mediated action.}, }
@article {pmid38881663, year = {2024}, author = {Li, X and Chang, J and Zhang, M and Zhou, Y and Zhang, T and Zhang, Y and Lu, R}, title = {The effect of environmental calcium on gene expression, biofilm formation and virulence of Vibrio parahaemolyticus.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1340429}, pmid = {38881663}, issn = {1664-302X}, abstract = {Calcium (Ca[2+]) can regulate the swarming motility and virulence of Vibrio parahaemolyticus BB22. However, the effects of Ca[2+] on the physiology of V. parahaemolyticus RIMD2210633, whose genomic composition is quite different with that of BB22, have not been investigated. In this study, the results of phenotypic assays showed that the biofilm formation, c-di-GMP production, swimming motility, zebrafish survival rate, cytoxicity against HeLa cells, and adherence activity to HeLa cells of V. parahaemolyticus RIMD2210633 were significantly enhanced by Ca[2+]. However, Ca[2+] had no effect on the growth, swarming motility, capsular polysaccharide (CPS) phase variation and hemolytic activity. The RNA sequencing (RNA-seq) assay disclosed 459 significantly differentially expressed genes (DEGs) in response to Ca[2+], including biofilm formation-associated genes and those encode virulence factors and putative regulators. DEGs involved in polar flagellum and T3SS1 were upregulated, whereas majority of those involved in regulatory functions and c-di-GMP metabolism were downregulated. The work helps us understand how Ca[2+] affects the behavior and gene expression of V. parahaemolyticus RIMD2210633.}, }
@article {pmid38877639, year = {2024}, author = {Afonso, AC and Simões, M and Saavedra, MJ and Simões, L and Lema, JM and Trueba-Santiso, A}, title = {Exploring coaggregation mechanisms involved in biofilm formation in drinking water through a proteomic-based approach.}, journal = {Journal of applied microbiology}, volume = {135}, number = {6}, pages = {}, doi = {10.1093/jambio/lxae143}, pmid = {38877639}, issn = {1365-2672}, support = {ED431C-2021/37//Galician Competitive Research Group/ ; FJC2019-041664-I//Juan de la Cierva-Formaci&#xf3;n/ ; PPBI-POCI-01-0145-FEDER-022122//Histology and Electron Microscopy/ ; 10.54499/2020.04773.BD//FCT/ ; UIDB/04469/2020//MCTES/ ; }, mesh = {*Biofilms/growth &amp; development ; *Drinking Water/microbiology ; *Proteomics ; *Flagella/metabolism ; Bacterial Proteins/metabolism/genetics ; Bacterial Adhesion ; Fimbriae, Bacterial/metabolism ; Water Microbiology ; Proteome ; }, abstract = {AIM: Coaggregation, a highly specific cell-cell interaction mechanism, plays a pivotal role in multispecies biofilm formation. While it has been mostly studied in oral environments, its occurrence in aquatic systems is also acknowledged. Considering biofilm formation's economic and health-related implications in engineered water systems, it is crucial to understand its mechanisms. Here, we hypothesized that traceable differences at the proteome level might determine coaggregation ability.<br><br>METHODS AND RESULTS: Two strains of Delftia acidovorans, isolated from drinking water were studied. First, in vitro motility assays indicated more swarming and twitching motility for the coaggregating strain (C+) than non-coaggregating strain (C-). By transmission electronic microscopy, we confirmed the presence of flagella for both strains. By proteomics, we detected a significantly higher expression of type IV pilus twitching motility proteins in C+, in line with the motility assays. Moreover, flagellum ring proteins were more abundant in C+, while those involved in the formation of the flagellar hook (FlE and FilG) were only detected in C-. All the results combined suggested structural and conformational differences between stains in their cell appendages.<br><br>CONCLUSION: This study presents an alternative approach for identifying protein biomarkers to detect coaggregation abilities in uncharacterized strains.}, }
@article {pmid38877618, year = {2024}, author = {Zhang, Z and Tang, Y and Tao, C and Zhang, J and Dong, F and Liu, S and Zhang, D and Wang, X}, title = {Mesoscopic ring element growth and deformation induced biofilm streamer evolution in microfluidic channels.}, journal = {Water science and technology : a journal of the International Association on Water Pollution Research}, volume = {89}, number = {11}, pages = {2867-2879}, pmid = {38877618}, issn = {0273-1223}, support = {11972074//National Natural Science Foundation of China/ ; 11772047//National Natural Science Foundation of China/ ; //National Natural Science Foundation of China/ ; 12372321//National Natural Science Foundation of China/ ; }, mesh = {*Biofilms/growth &amp; development ; Microfluidics ; Microfluidic Analytical Techniques/instrumentation ; }, abstract = {In a fluid environment, biofilms usually form and grow into streamers attached to solid surfaces. Existing research on single streamers studied their formation and failure modes. In the experiment on biofilm growth in a microfluidic channel, we found that rings composed of bacteria and an extracellular matrix are important elements on a mesoscopic scale. In the fluid environment, the failure of these ring elements causes damage to streamers. We simulated the growth and deformation of the ring structure in the micro-channel using multi-agent simulation and fluid-structure coupling of a porous elastic body. Based on this, we simulated the biofilm evolution involving multi-ring deformation, which provides a new length scale to study the biofilm streamer dynamics in fluid environments.}, }
@article {pmid38877452, year = {2024}, author = {Saqr, E and Sadik, MW and El-Didamony, G and Askora, A}, title = {Analysis of a new phage, KZag1, infecting biofilm of Klebsiella pneumoniae: genome sequence and characterization.}, journal = {BMC microbiology}, volume = {24}, number = {1}, pages = {211}, pmid = {38877452}, issn = {1471-2180}, mesh = {*Klebsiella pneumoniae/virology/genetics ; *Biofilms/growth &amp; development ; *Genome, Viral ; *Bacteriophages/genetics/physiology/classification/isolation &amp; purification ; Myoviridae/genetics/physiology/classification ; Drug Resistance, Multiple, Bacterial/genetics ; Phylogeny ; DNA, Viral/genetics ; Base Composition ; Phage Therapy ; }, abstract = {BACKGROUND: This study investigates the effectiveness of the bacteriophage KZag1 against drug-resistant Klebsiella pneumoniae, aiming to assess its potential as a therapeutic agent. The novelty lies in the characterization of KZag1, a Myovirus with specific efficacy against multidrug-resistant K. pneumoniae strains. This highlights the significance of exploring alternative strategies, particularly phage therapy, in addressing biofilm-associated infections.<br><br>METHODS: KZag1, characterized by a typical Myovirus structure with a 75&#x2009;&#xb1;&#x2009;5 nm diameter icosahedral head and a 15&#x2009;&#xb1;&#x2009;5 nm short tail, was evaluated in experimental trials against 15 strains of K. pneumoniae. The infection cycle duration was determined to be 50 min, resulting in an estimated burst size of approximately 83 plaque-forming units per colony-forming unit (PFU/CFU). Stability assessments were conducted within a pH range of 4 to 12 and temperatures ranging from 45&#xb0;C to 60&#xb0;C. Biofilm biomass reduction was observed, particularly at a multiplicity of infection (MOI) of 10.<br><br>RESULTS: KZag1 demonstrated infection efficacy against 12 out of 15 tested K. pneumoniae strains. The phage exhibited stability across a broad pH range and at elevated temperatures. Notably, treatment with KZag1 significantly reduced K. pneumoniae biofilm biomass, emphasizing its potential in combating biofilm formation. Genomic analysis revealed a complete genome of 157,089 base pairs with a GC content of 46.38%, encompassing 203 open reading frames (ORFs) and a cysteine-specific tRNA sequence. Comparison with phage GP4 highlighted similarities, with KZag1 having a longer genome by approximately 4829 base pairs and a higher GC content by approximately 0.93%. Phylogenetic analysis classified KZag1 within the Myoviridae family.<br><br>CONCLUSION: The efficacy of KZag1 against K. pneumoniae biofilm suggests its potential as a therapeutic candidate, especially for drug-resistant infections. Further clinical research is warranted to explore its synergy with other treatments, elucidate genomic traits, compare with Myoviridae phages, and understand its host interactions. These findings underscore the promising role of KZag1 in addressing drug-resistant bacterial infections.}, }
@article {pmid38874781, year = {2024}, author = {Yu, G and Xi, H and Sheng, T and Lin, J and Luo, Z and Xu, J}, title = {Sub-inhibitory concentrations of tetrabromobisphenol A induce the biofilm formation of methicillin-resistant Staphylococcus aureus.}, journal = {Archives of microbiology}, volume = {206}, number = {7}, pages = {301}, pmid = {38874781}, issn = {1432-072X}, support = {202210654//The Science and Technology Project of Jiangxi Health Commission/ ; 202210216//The Science and Technology Project of Jiangxi Health Commission/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Methicillin-Resistant Staphylococcus aureus/drug effects/genetics/physiology ; *Polybrominated Biphenyls/pharmacology ; Humans ; *Microbial Sensitivity Tests ; Xanthophylls/metabolism/pharmacology ; Anti-Bacterial Agents/pharmacology ; Bacterial Proteins/genetics/metabolism ; Gene Expression Regulation, Bacterial/drug effects ; }, abstract = {Biofilm formation by methicillin-resistant Staphylococcus aureus (MRSA) on indwelling medical devices complicates the treatment of infection. Tetrabromobisphenol A (TBBPA), a synthetic, lipophilic, halogenated aromatic compound widely used as an additive in plastics and electronic products, has raised environmental concerns due to its potential for bioaccumulation. This study investigated the impact of sub-inhibitory concentrations of TBBPA on MRSA biofilm formation. Crystal violet staining and confocal laser scanning microscopy analysis demonstrated that 1/8 MIC (0.5 µg/mL) of TBBPA significantly stimulated MRSA biofilm formation (P < 0.0001). MTT assays indicated that the metabolic activity within the biofilms increased by 15.60-40.85% compared to untreated controls. Dot blot immunoassay, autolysis assay, and extracellular DNA (eDNA) quantification further revealed TBBPA enhanced the production of polysaccharide intercellular adhesin (PIA) and eDNA, which are key biofilm components. Additionally, TBBPA was found to enhance the production of staphyloxanthin, facilitating MRSA survival under oxidative conditions and in human whole blood. RT-qPCR analysis showed that TBBPA significantly upregulated genes associated with biofilm formation (icaA, atlA, sarA), staphyloxanthin biosynthesis (crtM and sigB), and oxidative stress responses (sodA and katA). These findings suggest that TBBPA promotes MRSA biofilm development and enhances bacterial resistance to adverse conditions, thereby potentially exacerbating risks to human health.}, }
@article {pmid38873153, year = {2024}, author = {Li, S and Wang, Y and Xu, G and Xu, Y and Fu, C and Zhao, Q and Xu, L and Jia, X and Zhang, Y and Liu, Y and Qiao, J}, title = {The combination of allicin with domiphen is effective against microbial biofilm formation.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1341316}, pmid = {38873153}, issn = {1664-302X}, abstract = {BACKGROUND: Microorganisms in biofilms are particularly difficult to control because of their increased survival and antibiotic resistance. Allicin and domiphen were employed to inhibit the microbial growth and biofilm formation of Staphylococcus aureus, Escherichia coli, and Candida albicans strains.<br><br>METHODS: Broth microdilution method and checkerboard assay were conducted to determine the efficacy of allicin combined with domiphen against S. aureus, E. coli, and C. albicans. Microbial biofilm formation was measured using the crystal violet staining method and fluorescence microscopy. And the total viable count of the biofilm cells on material surface after the treatment with antimicrobial reagents was calculated with the plate count technique.<br><br>RESULTS: The two drugs showed synergistic effects against the pathogens with a fractional bactericidal concentration of less than 0.38. The combination of 64&#x2009;&#x3bc;g/mL allicin with 1&#x2009;&#x3bc;g/mL domiphen dispersed over 50% of the biofilm mass of S. aureus, E. coli, and C. albicans. In addition, the drug combination reduced the total viable counts of E. coli and C. albicans biofilm cells on stainless steel and polyethylene surfaces by more than 10[2] CFU/mL.<br><br>CONCLUSION: The combination of allicin and domiphen is an effective strategy for efficiently decreasing biofilms formation on various industrial materials surfaces.}, }
@article {pmid38872906, year = {2024}, author = {}, title = {Mucus-Permeable Sonodynamic Therapy Mediated Amphotericin B-Loaded PEGylated PLGA Nanoparticles Enable Eradication of Candida Albicans Biofilm [Retraction].}, journal = {International journal of nanomedicine}, volume = {19}, number = {}, pages = {5439-5440}, doi = {10.2147/IJN.S481636}, pmid = {38872906}, issn = {1178-2013}, abstract = {[This retracts the article DOI: 10.2147/IJN.S437726.].}, }
@article {pmid38870058, year = {2024}, author = {Greenwich, JL and Eagan, JL and Feirer, N and Boswinkle, K and Minasov, G and Shuvalova, L and Inniss, NL and Raghavaiah, J and Ghosh, AK and Satchell, KJF and Allen, KD and Fuqua, C}, title = {Control of biofilm formation by an Agrobacterium tumefaciens pterin-binding periplasmic protein conserved among diverse Proteobacteria.}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, volume = {121}, number = {25}, pages = {e2319903121}, pmid = {38870058}, issn = {1091-6490}, support = {75N93022C00035/AI/NIAID NIH HHS/United States ; GM120337//HHS | NIH | National Institute of General Medical Sciences (NIGMS)/ ; R37 AI150466/AI/NIAID NIH HHS/United States ; R01 AI150466/AI/NIAID NIH HHS/United States ; T32 GM007757/GM/NIGMS NIH HHS/United States ; P30 CA060553/CA/NCI NIH HHS/United States ; AI150466//HHS | National Institutes of Health (NIH)/ ; R01 GM120337/GM/NIGMS NIH HHS/United States ; CHE 2105598//National Science Foundation (NSF)/ ; HHSN272201700060C/AI/NIAID NIH HHS/United States ; }, mesh = {*Biofilms/growth &amp; development ; *Agrobacterium tumefaciens/metabolism/genetics ; *Pterins/metabolism ; *Cyclic GMP/metabolism/analogs &amp; derivatives ; *Bacterial Proteins/metabolism/genetics ; Proteobacteria/metabolism/genetics ; Molybdenum Cofactors ; Periplasm/metabolism ; Periplasmic Proteins/metabolism/genetics ; Periplasmic Binding Proteins/metabolism/genetics ; Gene Expression Regulation, Bacterial ; }, abstract = {Biofilm formation and surface attachment in multiple Alphaproteobacteria is driven by unipolar polysaccharide (UPP) adhesins. The pathogen Agrobacterium tumefaciens produces a UPP adhesin, which is regulated by the intracellular second messenger cyclic diguanylate monophosphate (c-di-GMP). Prior studies revealed that DcpA, a diguanylate cyclase-phosphodiesterase, is crucial in control of UPP production and surface attachment. DcpA is regulated by PruR, a protein with distant similarity to enzymatic domains known to coordinate the molybdopterin cofactor (MoCo). Pterins are bicyclic nitrogen-rich compounds, several of which are produced via a nonessential branch of the folate biosynthesis pathway, distinct from MoCo. The pterin-binding protein PruR controls DcpA activity, fostering c-di-GMP breakdown and dampening its synthesis. Pterins are excreted, and we report here that PruR associates with these metabolites in the periplasm, promoting interaction with the DcpA periplasmic domain. The pteridine reductase PruA, which reduces specific dihydro-pterin molecules to their tetrahydro forms, imparts control over DcpA activity through PruR. Tetrahydromonapterin preferentially associates with PruR relative to other related pterins, and the PruR-DcpA interaction is decreased in a pruA mutant. PruR and DcpA are encoded in an operon with wide conservation among diverse Proteobacteria including mammalian pathogens. Crystal structures reveal that PruR and several orthologs adopt a conserved fold, with a pterin-specific binding cleft that coordinates the bicyclic pterin ring. These findings define a pterin-responsive regulatory mechanism that controls biofilm formation and related c-di-GMP-dependent phenotypes in A. tumefaciens and potentially acts more widely in multiple proteobacterial lineages.}, }
@article {pmid38869956, year = {2024}, author = {Al-Enazi, NM}, title = {Evaluation of biofilm formation and expression of psl, pel, alg genes of Pseudomonas aeruginosa in exposure to detergents.}, journal = {Acta microbiologica et immunologica Hungarica}, volume = {71}, number = {2}, pages = {127-133}, doi = {10.1556/030.2024.02277}, pmid = {38869956}, issn = {1588-2640}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Pseudomonas aeruginosa/genetics/drug effects/physiology ; *Bacterial Proteins/genetics ; *Gene Expression Regulation, Bacterial/drug effects ; *Detergents/pharmacology ; *Microbial Sensitivity Tests ; Humans ; }, abstract = {Pseudomonas aeruginosa has been in the center of attention for several years as an opportunistic human pathogen implicated in many severe acute and chronic infections particularly in immunocompromised patients. Its high persistence and resistance against many antimicrobial agents are mostly attributed to biofilm formation. Biofilms are microbial communities mainly consisting of extracellular polymeric substances that encapsulate bacteria together and protect them from extracellular stresses. This cell aggregation is a stress response that P. aeruginosa employes as a survival strategy during growth with the toxic detergents. This process has shown to involve several operons such as psl, pel, and alg. Here we used P. aeruginosa strain PAO1 in control group, 40 P. aeruginosa strains from sink and 40 strains from surface of public places. Biofilm formation and gene expression were measured before and after exposure to sub minimum inhibitory concentration (sub-MIC) of biocides chlorhexidine diacetate and benzalkonium chloride. The qRT-PCR and biofilm formation results demonstrated an increase in biofilm formation ability and gene expression of pslA/B and pelA/B in two groups collected from sink and surface in contrast to the control group. A remarkable increase was observed in the biofilm formation and expression of pslA in the bacterial strain collected from the sink after exposure to biocides chlorhexidine diacetate. Both Pel and Psl appeared to have redundant functions as structural scaffolds in biofilms. Sub-MIC levels of detergents can improve biofilm formation ability of P. aeruginosa and therefore trigger resistance.}, }
@article {pmid38867987, year = {2024}, author = {Kumari, P and Kumar, D}, title = {Cultivation of algal biofilm and mat communities from the Garhwal Himalayas for possible use in diverse biotechnological applications.}, journal = {Heliyon}, volume = {10}, number = {11}, pages = {e32057}, pmid = {38867987}, issn = {2405-8440}, abstract = {The current study aimed to screen biofilm-/mat-forming and fast-growing algal communities from the Garhwal Himalayas, India. A total of 15 biofilm/mat-forming algal samples were collected, 8 biofilms out of these could be cultured and analyzed for their growth and development with time. Light microscopy was used to identify different types of cyanobacteria and algae present in the different collected biofilms/mats. Four biofilm and mat communities, namely biofilms #E, #F, #G, and #H, were found to have fast growth and were quick to colonize the substratum. Nylon net was identified as the most cost-effective and best-supporting material for biofilm development and biomass production. The study also found that increasing the harvesting frequency from the nylon net-enmeshed biofilms at least once a week would enhance the final biomass yield compared to harvesting the community once after a longer growth duration. Nevertheless, the findings reported here will be useful for researchers in developing phototrophic biofilm-based technology using nylon net, as it will be mechanically strong, supportive, and easy to handle.}, }
@article {pmid38867926, year = {2023}, author = {Qin, P and Cui, H and Li, P and Wang, S and Fan, S and Lu, J and Sun, M and Zhang, H and Wang, S and Su, X and Fu, HH and Hu, X and Lin, J and Zhang, YZ and Ding, W and Zhang, W}, title = {Early stage of biofilm assembly on microplastics is structured by substrate size and bacterial motility.}, journal = {iMeta}, volume = {2}, number = {3}, pages = {e121}, pmid = {38867926}, issn = {2770-596X}, abstract = {The taxonomic structure of biofilms on 0.3-mm microplastics differed significantly from that on 3-mm microplastics or glass particles. Compared with the 3-mm microplastics, biofilms on 0.3-mm microplastics were enriched for genes involved in flagellar-based motility and chemotaxis, pointing to a more 'mobile' community. The association between motility and bacterial colonization of 0.3-mm microplastics was observed through laboratory experiments using isolated strains.}, }
@article {pmid38866718, year = {2024}, author = {Singh, R and Shukla, J and Ali, M and Dubey, AK}, title = {A novel diterpenic derivative produced by Streptomyces chrestomyceticus ADP4 is a potent inhibitor of biofilm and virulence factors in Candida albicans and C. auris.}, journal = {Journal of applied microbiology}, volume = {135}, number = {6}, pages = {}, doi = {10.1093/jambio/lxae139}, pmid = {38866718}, issn = {1365-2672}, support = {SERB-EMR/2017/000254//Science and Engineering Research Board/ ; }, mesh = {*Biofilms/drug effects ; *Streptomyces/metabolism ; *Antifungal Agents/pharmacology ; *Candida albicans/drug effects ; *Microbial Sensitivity Tests ; *Virulence Factors ; Humans ; Candida/drug effects ; }, abstract = {AIM: Isolation, identification, structural and functional characterization of potent anti-Candida compound with specific antagonistic activities against significant human pathogens, Candida albicans and C. auris.<br><br>METHODS AND RESULTS: The compound (55B3) was purified from the metabolites produced by Streptomyces chrestomyceticus ADP4 by employing column chromatography. The structure of 55B3 was determined from the analyses of spectral data that included LCMS, nuclear magnetic resonance, FTIR, and UV spectroscopies. It was identified as a novel derivative of diterpenic aromatic acid, 3-(dictyotin-11'-oate-15'&#x3b1;, 19'&#x3b2;-olide)-4-(dictyotin-11'-oate-15&#x2033;&#x3b1;, 19&#x2033;&#x3b2;-olide)-protocatechoic acid. The compound displayed potent antifungal and anti-biofilm activities against C. albicans ATCC 10231 (Minimum Inhibitory Concentration, MIC90:14.94&#xa0;&#xb1;&#xa0;0.17 &#x3bc;gmL-1 and MBIC90: 16.03&#xa0;&#xb1;&#xa0;1.1 &#x3bc;gmL-1) and against C. auris CBS 12372 (MIC90: 21.75&#xa0;&#xb1;&#xa0;1.5 &#x3bc;gmL-1 and Minimum Biofilm Inhibitory Concentration, MBIC90: 18.38&#xa0;&#xb1;&#xa0;1.78 &#x3bc;gmL-1). Further, pronounced inhibition of important virulence attributes of Candida spp., e.g. yeast-to-hyphae transition, secretory aspartyl proteinase and phospholipase B by 55B3 was noted at subinhibitory concentrations. A plausible mechanism of anti-Candida action of the compound appeared to be the inhibition of ergosterol biosynthesis, which was inhibited by 64&#xa0;&#xb1;&#xa0;3% at the MIC90 value. The non-cytotoxic attribute of the compound was noted in the liver cell line (HepG2 cells).<br><br>CONCLUSION: The present work led to the discovery of a novel diterpenic derivative produced by S. chrestomyceticus ADP4. The compound displayed potent anti-Candida activity, particularly against the two most significant human pathogens, C. albicans and C. auris, which underlined its significance as a potential drug candidate for infections involving these pathogens.}, }
@article {pmid38866243, year = {2024}, author = {Ding, L and Wang, G and Wang, J and Peng, Y and Cai, S and Khan, SU and Cui, Z and Zhang, X and Wu, C and Smyth, H}, title = {Targeted treatment for biofilm-based infections using PEGylated tobramycin.}, journal = {Journal of controlled release : official journal of the Controlled Release Society}, volume = {372}, number = {}, pages = {43-58}, doi = {10.1016/j.jconrel.2024.06.022}, pmid = {38866243}, issn = {1873-4995}, mesh = {*Tobramycin/administration &amp; dosage/pharmacology/therapeutic use ; *Biofilms/drug effects ; Animals ; *Polyethylene Glycols/chemistry ; *Pseudomonas aeruginosa/drug effects ; *Anti-Bacterial Agents/administration &amp; dosage/pharmacology/therapeutic use/chemistry ; *Pseudomonas Infections/drug therapy ; Rats, Sprague-Dawley ; Male ; Rats ; Microbial Sensitivity Tests ; }, abstract = {Chronic infections often involve biofilm-based bacteria, in which the biofilm results in significant resistance against antimicrobial agents and prevents eradication of the infection. The physicochemical barrier presented by the biofilm matrix is a major impediment to the delivery of many antibiotics. Previously, PEGylation has been shown to improve antibiotic penetration into biofilms in vitro. In these studies, PEGylating tobramycin was investigated both in vitro and in vivo. Two distinct PEGylated tobramycin molecules were synthesized (mPEG-SA-Tob and mPEG-AA-Tob). Then, in a P. aeruginosa biofilm in vitro model, we found that mPEG-SA-Tob can operate as a prodrug and showed 7 times more effectiveness than tobramycin (MIC80: 14 μM vs.100 μM). This improved biofilm eradication is attributable to the fact that mPEG-SA-Tob can aid tobramycin to penetrate through the biofilm and overcome the alginate-mediated antibiotic resistance. Finally, we used an in vivo biofilm-based chronic pulmonary infection rat model to confirm the therapeutic impact of mPEG-SA-Tob on biofilm-based chronic lung infection. mPEG-SA-Tob has a better therapeutic impact than tobramycin in that it cannot only stop P. aeruginosa from multiplying in the lungs but can also reduce inflammation caused by infections and prevent a recurrence infection. Overall, our findings show that PEGylated tobramycin is an effective treatment for biofilm-based chronic lung infections.}, }
@article {pmid38866149, year = {2024}, author = {Tolotti, M and Brighenti, S and Bruno, MC and Cerasino, L and Pindo, M and Tirler, W and Albanese, D}, title = {Ecological "Windows of opportunity" influence biofilm prokaryotic diversity differently in glacial and non-glacial Alpine streams.}, journal = {The Science of the total environment}, volume = {944}, number = {}, pages = {173826}, doi = {10.1016/j.scitotenv.2024.173826}, pmid = {38866149}, issn = {1879-1026}, mesh = {*Ice Cover ; *Rivers/microbiology ; *Biofilms ; Italy ; Biodiversity ; Environmental Monitoring ; Ecosystem ; Bacteria/classification ; }, abstract = {In glacier-fed streams, the Windows of Opportunity (WOs) are periods of mild environmental conditions supporting the seasonal development of benthic microorganisms. WOs have been defined based on changes in biofilm biomass, but the responses of microbial diversity to WOs in Alpine streams have been overlooked. A two year (2017-2018) metabarcoding of epilithic and epipsammic biofilm prokaryotes was conducted in Alpine streams fed by glaciers (kryal), rock glaciers (rock glacial), or groundwater/precipitation (krenal) in two catchments of the Central-Eastern European Alps (Italy), aiming at testing the hypothesis that: 1) environmental WOs enhance not only the biomass but also the α-diversity of the prokaryotic biofilm in all stream types, 2) diversity and phenology of prokaryotic biofilm are mainly influenced by the physical habitat in glacial streams, and by water chemistry in the other two stream types. The study confirmed kryal and krenal streams as endmembers of epilithic and sediment prokaryotic α- and β-diversity, with rock glacial streams sharing a large proportion of taxa with the two other stream types. Alpha-diversity appeared to respond to ecological WOs, but, contrary to expectations, seasonality was less pronounced in the turbid kryal than in the clear streams. This was attributed to the small size of the glaciers feeding the studied kryal streams, whose discharge dynamics were those typical of the late phase of deglaciation. Prokaryotic α-diversity of non-glacial streams tended to be higher in early summer than in early autumn. Our findings, while confirming that high altitude streams are heavily threatened by climate change, underscore the still neglected role of rock glacier runoffs as climate refugia for the most stenothermic benthic aquatic microorganism. This advocates the need to define and test strategies for protecting these ecosystems for preserving, restoring, and connecting cold Alpine aquatic biodiversity in the context of the progressing global warming.}, }
@article {pmid38865453, year = {2024}, author = {Wang, X and Zhang, B and Zhang, J and Jiang, X and Liu, K and Wang, H and Yuan, X and Xu, H and Zheng, Y and Ma, G and Zhong, C}, title = {Conformal and conductive biofilm-bridged artificial Z-scheme system for visible light-driven overall water splitting.}, journal = {Science advances}, volume = {10}, number = {24}, pages = {eadn6211}, pmid = {38865453}, issn = {2375-2548}, abstract = {Semi-artificial Z-scheme systems offer promising potential toward efficient solar-to-chemical conversion, yet sustainable and stable designs are currently lacking. Here, we developed a sustainable hybrid Z-scheme system capable for visible light-driven overall water splitting by integrating the durability of inorganic photocatalysts with the interfacial adhesion and regenerative property of bacterial biofilms. The Z-scheme configuration is fabricated by drop casting a mixture of photocatalysts onto a glass plate, followed by the growth of biofilms for conformal conductive paste through oxidative polymerization of pyrrole molecules. Notably, the system exhibited scalability indicated by consistent catalytic efficiency across various sheet areas, resistance observed by remarkable maintaining of photocatalytic efficiency across a range of background pressures, and high stability as evidenced by minimal decay of photocatalytic efficiency after 100-hour reaction. Our work thus provides a promising avenue toward sustainable and high-efficiency artificial photosynthesis, contributing to the broader goal of sustainable energy solutions.}, }
@article {pmid38864863, year = {2024}, author = {Berenjian, A and Mahdinia, E and Demirci, A}, title = {Sustainable menaquinone-7 production through continuous fermentation in biofilm bioreactors.}, journal = {Bioprocess and biosystems engineering}, volume = {47}, number = {7}, pages = {1107-1116}, pmid = {38864863}, issn = {1615-7605}, support = {Project #PEN04850 (Accession #7005668)//National Institute of Food and Agriculture/ ; Project #PEN04876 (Accession #7005757)//National Institute of Food and Agriculture/ ; }, mesh = {*Biofilms/growth &amp; development ; *Vitamin K 2/metabolism/analogs &amp; derivatives ; *Bioreactors ; *Bacillus subtilis/metabolism/growth &amp; development ; Fermentation ; }, abstract = {Menaquinone-7 (MK-7), a vital vitamin with numerous health benefits, is synthesized and secreted extracellularly by the formation of biofilm, dominantly in Bacillus strains. Our team developed an innovative biofilm reactor utilizing Bacillus subtilis natto cells to foster biofilm growth on plastic composite supports to produce MK-7. Continuous fermentation in biofilm reactors offers a promising strategy for achieving sustainable and efficient production of Menaquinone-7 (MK-7). Unlike conventional batch fermentation, continuous biofilm reactors maintain a steady state of operation, which reduces resource consumption and waste generation, contributing to sustainability. By optimizing fermentation conditions, MK-7 production was significantly enhanced in this study, demonstrating the potential for sustainable industrial-scale production. To determine the optimal operational parameters, various dilution rates were tested. These rates were selected based on their potential to enhance nutrient supply and biofilm stability, thereby improving MK-7 production. By carefully considering the fermentation conditions and systematically varying the dilution rates, MK-7 production was significantly enhanced during continuous fermentation. The MK-7 productivity was found to increase from 0.12 mg/L/h to 0.33 mg/L/h with a dilution rate increment from 0.007 to 0.042 h[-1]). This range was chosen to explore the impact of various nutrient supply rates on MK-7 production and to identify the optimal conditions for maximizing productivity. However, a further increase in the dilution rate to 0.084 h[-1] led to reduced productivity at approximately 0.16 mg/L/h, likely due to insufficient retention time for effective biofilm formation. Consequently, a dilution rate of 0.042 h[-1] exhibited the highest productivity of 0.33 mg/L/h, outperforming all investigated dilution rates and demonstrating the critical balance between nutrient supply and retention time in continuous fermentation. These findings validate the feasibility of operating continuous fermentation at a 0.084 h[-1] dilution rate, corresponding to a 48 h retention time, to achieve the highest MK-7 productivity compared to conventional batch fermentation. The significant advancements achieved in enhancing Menaquinone-7 (MK-7) productivity through continuous fermentation at optimal dilution rates in the present work indicate promising prospects for even greater efficiency and sustainability in MK-7 production through future developments.}, }
@article {pmid38860142, year = {2024}, author = {Top, J and Zhang, X and Hendrickx, APA and Boeren, S and van Schaik, W and Huebner, J and Willems, RJL and Leavis, HL and Paganelli, FL}, title = {YajC, a predicted membrane protein, promotes Enterococcus faecium biofilm formation in vitro and in a rat endocarditis model.}, journal = {FEMS microbes}, volume = {5}, number = {}, pages = {xtae017}, pmid = {38860142}, issn = {2633-6685}, abstract = {Biofilm formation is a critical step in the pathogenesis of difficult-to-treat Gram-positive bacterial infections. We identified that YajC, a conserved membrane protein in bacteria, plays a role in biofilm formation of the clinically relevant Enterococcus faecium strain E1162. Deletion of yajC conferred significantly impaired biofilm formation in vitro and was attenuated in a rat endocarditis model. Mass spectrometry analysis of supernatants of washed ΔyajC cells revealed increased amounts in cytoplasmic and cell-surface-located proteins, including biofilm-associated proteins, suggesting that proteins on the surface of the yajC mutant are only loosely attached. In Streptococcus mutans YajC has been identified in complex with proteins of two cotranslational membrane protein-insertion pathways; the signal recognition particle (SRP)-SecYEG-YajC-YidC1 and the SRP-YajC-YidC2 pathway, but its function is unknown. In S. mutans mutation of yidC1 and yidC2 resulted in impaired protein insertion in the cell membrane and secretion in the supernatant. The E. faecium genome contains all homologous genes encoding for the cotranslational membrane protein-insertion pathways. By combining the studies in S. mutans and E. faecium, we propose that YajC is involved in the stabilization of the SRP-SecYEG-YajC-YidC1 and SRP-YajC-Yid2 pathway or plays a role in retaining proteins for proper docking to the YidC insertases for translocation in and over the membrane.}, }
@article {pmid38860138, year = {2024}, author = {Chu, LT and Laxman, D and Abdelhamed, J and Pirlo, RK and Fan, F and Wagner, N and Tran, TM and Bui, L}, title = {Development of a tomato xylem-mimicking microfluidic system to study Ralstonia pseudosolanacearum biofilm formation.}, journal = {Frontiers in bioengineering and biotechnology}, volume = {12}, number = {}, pages = {1395959}, pmid = {38860138}, issn = {2296-4185}, abstract = {The bacterial wilt pathogen Ralstonia pseudosolanacearum (Rps) colonizes plant xylem vessels and blocks the flow of xylem sap by its biofilm (comprising of bacterial cells and extracellular material), resulting in devastating wilt disease across many economically important host plants including tomatoes. The technical challenges of imaging the xylem environment, along with the use of artificial cell culture plates and media in existing in vitro systems, limit the understanding of Rps biofilm formation and its infection dynamics. In this study, we designed and built a microfluidic system that mimicked the physical and chemical conditions of the tomato xylem vessels, and allowed us to dissect Rps responses to different xylem-like conditions. The system, incorporating functional surface coatings of carboxymethyl cellulose-dopamine, provided a bioactive environment that significantly enhanced Rps attachment and biofilm formation in the presence of tomato xylem sap. Using computational approaches, we confirmed that Rps experienced linear increasing drag forces in xylem-mimicking channels at higher flow rates. Consistently, attachment and biofilm assays conducted in our microfluidic system revealed that both seeding time and flow rates were critical for bacterial adhesion to surface and biofilm formation inside the channels. These findings provided insights into the Rps attachment and biofilm formation processes, contributing to a better understanding of plant-pathogen interactions during wilt disease development.}, }
@article {pmid38860120, year = {2024}, author = {Zheng, S and Deng, R and Huang, G and Ou, Z and Shen, Z}, title = {Effects of honokiol combined with resveratrol on bacteria responsible for oral malodor and their biofilm.}, journal = {Journal of oral microbiology}, volume = {16}, number = {1}, pages = {2361402}, pmid = {38860120}, issn = {2000-2297}, abstract = {BACKGROUND: This study aimed to investigate the effect of honokiol combined with resveratrol on bacteria responsible for oral malodor and their biofilm.<br><br>METHOD: This study investigated drug's MIC, FICI and dynamic bactericidal susceptibility activities against Pg and Fn. The effects of drugs on biofilm metabolic activity, biofilm total amount, and biofilm microstructure were determined by CCK-8 experiment, semi-quantitative adhesion experiment and SEM, respectively. The effects of drugs on biofilm genes, extracellular polysaccharides, proteins and DNA content were determined by qRT-PCR, phenol-sulfuric acid method, BCA method and Nano Drop one C, respectively.<br><br>RESULTS: The combination had synergistic antibacterial effect on Pg and Fn. 1/2&#xd7;MIC and 1&#xd7;MIC combination inhibit the whole process of Pg and Fn growth. The results showed that the combination effectively reduce biofilm metabolic activity and total amount, and destroy biofilm microstructure. The results showed that the combination downregulate the gene expression both Pg and Fn, reduce extracellular polysaccharides and DNA of Pg, and reduce extracellular proteins and DNA of Fn.<br><br>CONCLUSION: This study showed that the combination had a synergistic antibacterial effect on Pg and Fn, reduced the biofilm extracellular matrix, inhibited biofilm formation, and downregulated the expression of genes related to biofilm formation.}, }
@article {pmid38857885, year = {2024}, author = {Zhang, C and Wang, C and Dai, J and Xiu, Z}, title = {The inhibition mechanism of co-cultured probiotics on biofilm formation of Klebsiella pneumoniae.}, journal = {Journal of applied microbiology}, volume = {135}, number = {6}, pages = {}, doi = {10.1093/jambio/lxae138}, pmid = {38857885}, issn = {1365-2672}, support = {21476042//National Natural Science Foundation of China/ ; DUT17ZD209//Fundamental Research Funds for the Central Universities/ ; }, mesh = {*Biofilms/growth &amp; development ; *Klebsiella pneumoniae/physiology ; Humans ; *Probiotics/pharmacology ; Caco-2 Cells ; *Coculture Techniques ; Bacillus subtilis/physiology/genetics ; Lacticaseibacillus rhamnosus/physiology ; Bacterial Adhesion ; Lactobacillus/physiology ; Cytokines/metabolism ; }, abstract = {AIMS: Klebsiella pneumoniae, an important opportunistic pathogen of nosocomial inflection, is known for its ability to form biofilm. The purpose of the current study is to assess how co- or mono-cultured probiotics affect K. pneumoniae's ability to produce biofilms and investigate the potential mechanisms by using a polyester nonwoven chemostat and a Caco-2 cell line.<br><br>METHODS AND RESULTS: Compared with pure cultures of Lactobacillus rhamnosus and Lactobacillus sake, the formation of K. pneumoniae biofilm was remarkably inhibited by the mixture of L. rhamnosus, L. sake, and Bacillus subtilis at a ratio of 5:5:1 by means of qPCR and FISH assays. In addition, Lactobacillus in combination with B. subtilis could considerably reduce the adherence of K. pneumoniae to Caco-2 cells by using inhibition, competition, and displacement assays. According to the RT-PCR assay, the adsorption of K. pneumoniae to Caco-2 cells was effectively inhibited by the co-cultured probiotics, leading to significant reduction in the expression of proinflammatory cytokines induced by K. pneumoniae. Furthermore, the HPLC and RT-PCR analyses showed that the co-cultured probiotics were able to successfully prevent the expression of the biofilm-related genes of K. pneumoniae by secreting plenty of organic acids as well as the second signal molecule (c-di-GMP), resulting in inhibition on biofilm formation.<br><br>CONCLUSION: Co-culture of L. sake, L. rhamnosus, and B. subtilis at a ratio of 5:5:1 could exert an antagonistic effect on the colonization of pathogenic K. pneumoniae by down-regulating the expression of biofilm-related genes. At the same time, the co-cultured probiotics could effectively inhibit the adhesion of K. pneumoniae to Caco-2 cells and block the expression of proinflammatory cytokines induced by K. pneumoniae.}, }
@article {pmid38857709, year = {2024}, author = {Wang, S and Deng, S and Wang, Y}, title = {Theaflavin-3,3'-digallate effectively attenuates biofilm formation by Enterococcus faecalis via the targeting of specific quorum sensing pathways.}, journal = {Microbial pathogenesis}, volume = {193}, number = {}, pages = {106739}, doi = {10.1016/j.micpath.2024.106739}, pmid = {38857709}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Enterococcus faecalis/drug effects/genetics ; *Quorum Sensing/drug effects ; *Biflavonoids/pharmacology ; *Gene Expression Regulation, Bacterial/drug effects ; *Anti-Bacterial Agents/pharmacology ; *Catechin/pharmacology/analogs &amp; derivatives ; Bacterial Proteins/genetics/metabolism ; Transcriptome/drug effects ; Gene Expression Profiling ; }, abstract = {Enterococcus faecalis, an opportunistic pathogen responsible for nosocomial infections, exhibits increased pathogenicity via biofilm formation. Theaflavin-3,3'-digallate (TF3), a theaflavin extracted from black tea, exhibits potent antibacterial effects. In the present study, we investigated the inhibitory effect of TF3 on E. faecalis. Our results indicated that TF3 significantly inhibited E. faecalis ATCC 29212 biofilm formation. This observation was further confirmed via crystal violet staining, confocal laser scanning microscopy, and field emission-scanning electron microscopy. To disclose the underlying mechanisms, RNA-seq was applied. TF3 treatment significantly altered the transcriptomic profile of E. faecalis, as evidenced by identification of 248 differentially expressed genes (DEGs). Through functional annotation of these DEGs, several quorum-sensing pathways were found to be suppressed in TF3-treated cultures. Further, gene expression verification via real-time PCR confirmed the downregulation of gelE, sprE, and secY by TF3. These findings highlighted the ability of TF3 to impede E. faecalis biofilm formation, suggesting a novel preventive strategy against E. faecalis infections.}, }
@article {pmid38857632, year = {2024}, author = {Im, HR and Im, SJ and Nguyen, DV and Jeong, SP and Jang, A}, title = {Real-time diagnosis and monitoring of biofilm and corrosion layer formation on different water pipe materials using non-invasive imaging methods.}, journal = {Chemosphere}, volume = {361}, number = {}, pages = {142577}, doi = {10.1016/j.chemosphere.2024.142577}, pmid = {38857632}, issn = {1879-1298}, mesh = {*Biofilms/growth &amp; development ; Corrosion ; *Iron/chemistry/analysis ; *Water Supply ; Environmental Monitoring/methods ; Aluminum/chemistry ; Polyvinyl Chloride/chemistry ; }, abstract = {Water distribution networks play a crucial role in ensuring a reliable water supply, yet they encounter challenges such as corrosion, scale formation, and biofilm growth due to interactions with environmental elements. Biofilms and corrosion layers are significant contaminants in water pipes, formed by complex interactions with pipe materials. As the structure of these contamination layers varies depending on the pipe material, it is essential to investigate the contamination layer for each material individually. Specifically, biofilm growth is typically investigated concerning organic sources, while the growth of humus layers is examined in relation to inorganic elements such as manganese (Mn), iron (Fe), and aluminum (Al), which are major elements and organic substances found in water pipes. Real-time imaging of recently contaminated layers can provide important insights to improve system performance by optimizing operations and cleaning processes. In this study, cast iron (7.10 ± 0.78 nm) exhibits greater surface roughness compared to PVC (5.60 ± 0.14 nm) and provides favorable conditions for biofilm formation due to its positive charge. Over a period of 425 h, the fouling layer on cast iron and PVC surfaces gradually increased in fouling thickness, porosity, roughness, and density, reaching maximum value of 29.72 ± 3.6 μm, 11.44 ± 1.1%, 41673 ± 1025.6 pixels, and 0.80 ± 0.3 fouling layer pixel/layer pixel for cast iron, and 8.15 ± 0.4 μm, 20.64 ± 0.9%, 35916.6 ± 755.7 pixels, and 0.58 ± 0.1 fouling layer pixel/layer pixel, respectively. Within the scope of the current research, CNN model demonstrates high correlation coefficients (0.98 and 0.91) in predicting biofilm thickness for cast iron and PVC. The model also presented high accuracy in predicting porosity for both materials (over 0.91 for cast iron and 0.96 for PVC). While the model accurately predicted biofilm roughness and density for cast iron (correlation coefficients 0.98 and 0.94, respectively), it had lower accuracy for PVC (correlation coefficients 0.92 for both parameters).}, }
@article {pmid38856934, year = {2024}, author = {Shan, L and Zheng, W and Xu, S and Zhu, Z and Pei, Y and Bao, X and Yuan, Y}, title = {Effect of household pipe materials on formation and chlorine resistance of the early-stage biofilm: various interspecific interactions exhibited by the same microbial biofilm in different pipe materials.}, journal = {Archives of microbiology}, volume = {206}, number = {7}, pages = {295}, pmid = {38856934}, issn = {1432-072X}, support = {GJJ2200645//Foundation of Jiangxi Educational Commission/ ; GJJ2200652//Foundation of Jiangxi Educational Commission/ ; 20212BAB214006//Youth Science Foundation of Jiangxi Province/ ; 51608198//National Natural Science Foundation of China/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Chlorine/pharmacology ; *Bacteria/drug effects/genetics/isolation &amp; purification/classification ; *Drinking Water/microbiology ; Copper/pharmacology ; Water Microbiology ; Stainless Steel ; Polypropylenes ; Water Supply ; Halogenation ; Corrosion ; Disinfectants/pharmacology ; }, abstract = {Microbial community biofilm exists in the household drinking water system and would pose threat to water quality. This paper explored biofilm formation and chlorination resistance of ten dual-species biofilms in three typical household pipes (stainless steel (SS), polypropylene random (PPR), and copper), and investigated the role of interspecific interaction. Biofilm biomass was lowest in copper pipes and highest in PPR pipes. A synergistic or neutralistic relationship between bacteria was evident in most biofilms formed in SS pipes, whereas four groups displayed a competitive relationship in biofilms formed in copper pipe. Chlorine resistance of biofilms was better in SS pipes and worse in copper pipes. It may be helped by interspecific relationships, but was more dependent on bacteria and resistance mechanisms such as more stable extracellular polymeric substance. The corrosion sites may also protect bacteria from chlorination. The findings provide useful insights for microbial control strategies in household drinking water systems.}, }
@article {pmid38856209, year = {2024}, author = {Wang, P and Xia, B and Chen, Z and Xie, J and Sun, X and Tian, Q and Gao, CH and Xun, W and Zhang, N and Zhang, R and Shen, Q and Xu, Z}, title = {An Approach to Constructing Multispecies Biofilm Communities from Rhizosphere Soil.}, journal = {Journal of visualized experiments : JoVE}, volume = {}, number = {207}, pages = {}, doi = {10.3791/66926}, pmid = {38856209}, issn = {1940-087X}, mesh = {*Biofilms/growth &amp; development ; *Rhizosphere ; *Soil Microbiology ; *RNA, Ribosomal, 16S/genetics ; Bacteria/genetics/isolation &amp; purification/classification ; Bacterial Physiological Phenomena ; }, abstract = {The multispecies biofilm is a naturally occurring and dominant lifestyle of bacteria in nature, including in rhizosphere soil, although the current understanding of it is limited. Here, we provide an approach to rapidly establish synergistic multispecies biofilm communities. The first step is to extract cells from rhizosphere soil using the differential centrifugation method. Afterward, these soil cells are inoculated into the culture medium to form pellicle biofilm. After 36 h of incubation, the bacterial composition of the biofilm and the solution underneath are determined using the 16S rRNA gene amplicon sequencing method. Meanwhile, high-throughput bacterial isolation from pellicle biofilm is conducted using the limiting dilution method. Then, the top 5 bacterial taxa are selected with the highest abundance in the 16S rRNA gene amplicon sequencing data (pellicle biofilm samples) for further use in constructing multispecies biofilm communities. All combinations of the 5 bacterial taxa were quickly established using a 24-well plate, selected for the strongest biofilm formation ability by the crystal violet staining assay, and quantified by qPCR. Finally, the most robust synthetic bacterial multispecies biofilm communities were obtained through the methods above. This methodology provides informative guidance for conducting research on rhizosphere multispecies biofilm and identifying representative communities for studying the principles governing interactions among these species.}, }
@article {pmid38855589, year = {2024}, author = {Tram, MK and Schammel, J and Vancavage, R and Welliver, C and Inouye, BM}, title = {Emerging strategies for the prevention of bacterial biofilm in prosthetic surgery.}, journal = {Translational andrology and urology}, volume = {13}, number = {5}, pages = {833-845}, pmid = {38855589}, issn = {2223-4691}, abstract = {Penile prosthesis implantation is an effective treatment for erectile dysfunction (ED) with high patient satisfaction and effectiveness. Unfortunately, infections remain a dreaded complication, often necessitating device removal and imposing a substantial healthcare cost. Biofilms are communities of microorganisms encased in a self-produced polymeric matrix that can attach to penile prostheses. Biofilms have been demonstrated on the majority of explanted prostheses for both infectious and non-infectious revisions and are prevalent even in asymptomatic patients. Biofilms play a role in microbial persistence and exhibit unique antibiotic resistance strategies that can lead to increased infection rates in revision surgery. Biofilms demonstrate physical barriers through the development of an extracellular polymeric substance (EPS) that hinders antibiotic penetrance and the bacteria within biofilms demonstrate reduced metabolic activity that weakens the efficacy of traditional antibiotics. Despite these challenges, new methods are being developed and investigated to prevent and treat biofilms. These treatments include surface modifications, biosurfactants, tissue plasminogen activator (tPA), and nitric oxide (NO) to prevent bacterial adhesion and biofilm formation. Additionally, novel antibiotic treatments are currently under investigation and include antimicrobial peptides (AMPs), bacteriophages, and refillable antibiotic coatings. This article reviews biofilm formation, the challenges that biofilms present to conventional antibiotics, current treatments, and experimental approaches for biofilm prevention and treatment.}, }
@article {pmid38853917, year = {2024}, author = {Snell, A and Manias, DA and Elbehery, RR and Dunny, GM and Willett, JLE}, title = {Arginine impacts aggregation, biofilm formation, and antibiotic susceptibility in Enterococcus faecalis.}, journal = {bioRxiv : the preprint server for biology}, volume = {}, number = {}, pages = {}, pmid = {38853917}, issn = {2692-8205}, support = {R01 AI122742/AI/NIAID NIH HHS/United States ; }, abstract = {Enterococcus faecalis is a commensal bacterium in the gastrointestinal tract (GIT) of humans and other organisms. E. faecalis also causes infections in root canals, wounds, the urinary tract, and on heart valves. E. faecalis metabolizes arginine through the arginine deiminase (ADI) pathway, which converts arginine to ornithine and releases ATP, ammonia, and CO2. E. faecalis arginine metabolism also affects virulence of other pathogens during co-culture. E. faecalis may encounter elevated levels of arginine in the GIT or the oral cavity, where arginine is used as a dental therapeutic. Little is known about how E. faecalis responds to growth in arginine in the absence of other bacteria. To address this, we used RNAseq and additional assays to measure growth, gene expression, and biofilm formation in E. faecalis OG1RF grown in arginine. We demonstrate that arginine decreases E. faecalis biofilm production and causes widespread differential expression of genes related to metabolism, quorum sensing, and polysaccharide synthesis. Growth in arginine also increases aggregation of E. faecalis and promotes decreased susceptibility to the antibiotics ampicillin and ceftriaxone. This work provides a platform for understanding of how the presence of arginine in biological niches affects E. faecalis physiology and virulence of surrounding microbes.}, }
@article {pmid38852803, year = {2024}, author = {Lyu, C and Hu, H and Cai, L and He, S and Xu, X and Zhou, G and Wang, H}, title = {A trans-acting sRNA SaaS targeting hilD, cheA and csgA to inhibit biofilm formation of S. Enteritidis.}, journal = {Journal of advanced research}, volume = {}, number = {}, pages = {}, doi = {10.1016/j.jare.2024.06.008}, pmid = {38852803}, issn = {2090-1224}, abstract = {INTRODUCTION: Salmonella Enteritidis has brought great harm to public health, animal production and food safety worldwide. The biofilm formed by Salmonella Enteritidis plays a critical role in microbial cross-contamination. Small non-coding RNAs (sRNAs) have been demonstrated to be responsible for regulating the formation of biofilm. The sRNA SaaS has been identified previously, that promotes pathogenicity by regulating invasion and virulence factors. However, whether the SaaS is implicated in regulating biofilm formation in abiotic surfaces remains unclear.<br><br>OBJECTIVES: This study aimed to clarify the effect of SaaS in Salmonella Enteritidis and explore the modulatory mechanism on the biofilm formation.<br><br>METHODS: Motility characteristics and total biomass of biofilm of test strains were investigated by the phenotypes in three soft agar plates and crystal violet staining in polystyrene microplates. Studies of microscopic structure and extracellular polymeric substances (EPS) of biofilm on solid surfaces were carried out using confocal laser scanning microscope (CLSM) and Raman spectra. Transcriptomics and proteomics were applied to analyze the changes of gene expression and EPS component. The RNA-protein pull-down and promoter-reporter &#x3b2;-galactosidase activity assays were employed to analyze RNA binding proteins and identify target mRNAs, respectively.<br><br>RESULTS: SaaS inhibits biofilm formation by repressing the adhesion potential and the secretion of EPS components. Integration of transcriptomics and proteomics analysis revealed that SaaS strengthened the expression of the flagellar synthesis system and downregulated the expression of curli amyloid fibers. Furthermore, RNA-protein pull-down interactome datasets indicated that SaaS binds to Hfq (an RNA molecular chaperone protein, known as a host factor for phage Qbeta RNA replication) uniquely among 193 candidate proteins, and promoter-reporter &#x3b2;-galactosidase activity assay confirmed target mRNAs including hilD, cheA, and csgA.<br><br>CONCLUSION: SaaS inhibits the properties of bacterial mobility, perturbs the secretion of EPS, and contributes to the inhibition of biofilm formation by interacting with target mRNA (hilD, cheA, and csgA) through the Hfq-mediated pathway.}, }
@article {pmid38851819, year = {2024}, author = {Ullah, I and Khan, SS and Ahmad, W and Liu, L and Rady, A and Aldahmash, B and Yu, Y and Wang, J and Wang, Y}, title = {NIR light-activated nanocomposites combat biofilm formation and enhance antibacterial efficacy for improved wound healing.}, journal = {Communications chemistry}, volume = {7}, number = {1}, pages = {131}, pmid = {38851819}, issn = {2399-3669}, abstract = {Nanoparticle-based therapies are emerging as a pivotal frontier in biomedical research, showing their potential in combating infections and facilitating wound recovery. Herein, selenium-tellurium dopped copper oxide nanoparticles (SeTe-CuO NPs) with dual photodynamic and photothermal properties were synthesized, presenting an efficient strategy for combating bacterial infections. In vitro evaluations revealed robust antibacterial activity of SeTe-CuO NPs, achieving up to 99% eradication of bacteria and significant biofilm inhibition upon near-infrared (NIR) irradiation. Moreover, in vivo studies demonstrated accelerated wound closure upon treatment with NIR-activated SeTe-CuO NPs, demonstrating their efficacy in promoting wound healing. Furthermore, SeTe-CuO NPs exhibited rapid bacterial clearance within wounds, offering a promising solution for wound care. Overall, this versatile platform holds great promise for combating multidrug-resistant bacteria and advancing therapeutic interventions in wound management.}, }
@article {pmid38851363, year = {2024}, author = {Ansari, MA and Alomary, MN}, title = {Bioinspired ferromagnetic NiFe2O4 nanoparticles: Eradication of fungal and drug-resistant bacterial pathogens and their established biofilm.}, journal = {Microbial pathogenesis}, volume = {193}, number = {}, pages = {106729}, doi = {10.1016/j.micpath.2024.106729}, pmid = {38851363}, issn = {1096-1208}, mesh = {*Biofilms/drug effects ; *Microbial Sensitivity Tests ; *Nickel/chemistry/pharmacology ; *Ferric Compounds/pharmacology/chemistry ; *Candida albicans/drug effects ; *Pseudomonas aeruginosa/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Methicillin-Resistant Staphylococcus aureus/drug effects ; Plant Extracts/pharmacology/chemistry ; Plant Leaves/chemistry/microbiology ; Aloe/chemistry ; X-Ray Diffraction ; Particle Size ; Microscopy, Electron, Scanning ; Antifungal Agents/pharmacology/chemistry ; Spectroscopy, Fourier Transform Infrared ; Nanoparticles/chemistry ; }, abstract = {Nickel ferrite nanoparticles (NiFe2O4 NPs) were synthesized using the medicinally important plant Aloe vera leaf extract, and their structural, morphological, and magnetic properties were characterized by x-ray diffraction (XRD), fourier transform infrared (FTIR), scanning electron microscopy (SEM), energy dispersive x-ray (EDX), and vibrating sample magnetometer (VSM). The synthesized NPs were soft ferromagnetic and spinel in nature, with an average particle size of 22.2 nm. To the best of our understanding, this is the first comprehensive investigation into the antibacterial, anticandidal, antibiofilm, and antihyphal properties of NiFe2O4 NPs against C. albicans as well as drug-resistant gram-positive methicillin-resistant Staphylococcus aureus (MRSA) and gram-negative multidrug resistant Pseudomonas aeruginosa (MDR-P. aeruginosa) bacteria. NiFe2O4 NPs showed potent antimicrobial activity (MIC 1.6-2 mg/mL) against the test pathogens. NiFe2O4 NPs at 0.5 mg/mL suppressed biofilm formation by 49.5-53.1 % in test pathogens. The study found that the NPs not only prevent the formation of biofilm, but also eliminate existing mature biofilms by 50.5-75.79 % at 0.5 mg/mL, which was further validated by SEM. SEM examination revealed a reduction in the number of cells that form biofilms and adhere to the surface. Additionally, it considerably impeded the colonization and aggregation of the biofilm strains on the glass surface. Light microscopic examination demonstrated that NPs effectively prevent the expansion of hyphae, filaments, and yeast-to-hyphae transformation in C. albicans, resulting in a substantial decrease in their ability to cause infection. Moreover, SEM images of the treated cells exhibited the presence of wrinkles, deformities, and impaired cell walls, which suggests an alteration and instability of the membrane. This study demonstrated the efficacy of the greenly manufactured NPs in suppressing the proliferation of candida, drug-resistant bacteria, and their preexisting biofilms, as well as yeast-to-hyphae transformation. Therefore, these NPs with broad spectrum applications could be utilized in health settings to mitigate biofilm-related health conditions caused by pathogenic microbial strains.}, }
@article {pmid38851334, year = {2024}, author = {Shahi, PB and Manandhar, S and Angove, MJ and Paudel, SR}, title = {Performance evaluation of species varied fixed bed biofilm reactor for wastewater treatment of Dhobi Khola outfall, Setopul, Kathmandu, Nepal.}, journal = {The Science of the total environment}, volume = {942}, number = {}, pages = {173752}, doi = {10.1016/j.scitotenv.2024.173752}, pmid = {38851334}, issn = {1879-1026}, mesh = {*Wastewater/chemistry ; *Bioreactors ; *Biofilms ; *Waste Disposal, Fluid/methods ; *Water Pollutants, Chemical/analysis ; *Metals, Heavy/analysis ; Nepal ; Biological Oxygen Demand Analysis ; }, abstract = {The sustainability of wastewater treatment plants poses significant challenges for developing countries, necessitating substantial investment for operation and maintenance. Biofilm reactors seeded with specific species of microorganisms were investigated under controlled environmental conditions. However, the performance evaluation of such reactors under natural conditions remains largely underexplored. This study investigated wastewater treatment capabilities of bench-scale fixed bed biofilm reactors, employing various species (Wastewater Microbes, Pseudomonas, Algae, and a co-culture of Algae and Pseudomonas). The reactors (Treatments and Control) were filled with 28 mm nominal-size local aggregates as packing media, operated under different contact times, and subjected to varying concentrations of heavy metals (Zn, Cd). To assess the reactor performances, the Bland-Altman Plot and Chemical Oxygen Demand (COD) removal kinetics were evaluated. The results revealed that the reactor initiated with a co-culture exhibited the optimal COD removal efficiency, reaching 84 ± 1 %. The reactor initially seeded with wastewater microbes exhibited the highest heavy metal elimination, achieving 94 ± 1 % and 88 ± 1 % removal for Zn and Cd respectively. The wastewater-seeded reactor demonstrated the zero-order COD removal kinetic coefficient (k) of 46.41 mg/L/h at an average influent COD concentration of 558 mg/L at 10 h contact time. While Pseudomonas-seeded reactor demonstrated k = 0.73 mg/L/h at 20 h contact time with 69 mg/L influent COD and heavy metal concentrations Zn = 26 mg/L and Cd = 3.57 mg/L. The findings of this study suggest that variations in environmental conditions, contact time, and heavy metal concentration have minimal impact on the pollutant removal efficacy of the reactors, and provide robust evidence for their viability as a sustainable alternative in municipal wastewater treatment. The study also identifies the possibility of treating specific wastewater characteristics by altering the dominant species in the reactors, paving the way for further research on the efficacy of other microbial genomes in fixed bed biofilm reactors.}, }
@article {pmid38850020, year = {2023}, author = {Karimzadeh Barenji, E and Beglari, S and Tahghighi, A and Azerang, P and Rohani, M}, title = {Evaluation of Anti-Bacterial and Anti-Biofilm Activity of Native Probiotic Strains of Lactobacillus Extracts.}, journal = {Iranian biomedical journal}, volume = {28}, number = {2&amp;3}, pages = {102-112}, pmid = {38850020}, issn = {2008-823X}, abstract = {BACKGROUND: Lactic acid bacteria produce various beneficial metabolites, including antimicrobial agents. Owing to the fast-rising antibiotic resistance among pathogenic microbes, scientists are exploring antimicrobials beyond antibiotics. In this study, we examined four Lactobacillus strains, namely L. plantarum 42, L. brevis 205, L. rhamnosus 239, and L. delbrueckii 263, isolated from healthy human microbiota, to evaluate their antibacterial and antifungal activity.<br><br>METHODS: Lactobacillus strains were cultivated, and the conditioned media were obtained. The supernatant was then used to treat pathogenic bacteria and applied to the growth media containing fungal and bacterial strains. Additionally, the supernatant was separated to achieve the organic and aqueous phases. The two phases were then examined in terms of bacterial and fungal growth rates. Disk diffusion and MIC tests were conducted to determine strains with the most growth inhibition potential. Finally, the potent strains identified through the MIC test were tested on the pathogenic microorganisms to assess their effects on the formation of pathogenic biofilms.<br><br>RESULTS: The organic phase of L. rhamnosus 239 extracts exhibited the highest antibacterial and antibiofilm effects, while that of L. brevis 205 demonstrated the most effective antifungal impact, with a MIC of 125 &#xb5;g/mL against Saccharomyces cerevisiae.<br><br>CONCLUSION: This study confirms the significant antimicrobial impacts of the lactic acid bacteria strains on pathogenic bacteria and fungi; hence, they could serve as a reliable alternative to antibiotics for a safe and natural protection against pathogenic microorganisms.}, }
@article {pmid38849892, year = {2024}, author = {Titouche, Y and Akkou, M and Djaoui, Y and Mechoub, D and Fatihi, A and Campaña-Burguet, A and Bouchez, P and Bouhier, L and Houali, K and Torres, C and Nia, Y and Hennekinne, JA}, title = {Nasal carriage of Staphylococcus aureus in healthy dairy cows in Algeria: antibiotic resistance, enterotoxin genes and biofilm formation.}, journal = {BMC veterinary research}, volume = {20}, number = {1}, pages = {247}, pmid = {38849892}, issn = {1746-6148}, support = {project PID2022-139591OB-I00 financed by MCIN/AEI/10.13039/501100011033/FEDER, UE//The experimental work performed in the University of La Rioja has been performed with project PID2022-139591OB-I00/ ; }, mesh = {Animals ; Cattle ; *Staphylococcus aureus/genetics/drug effects/isolation &amp; purification ; *Biofilms ; Algeria ; *Enterotoxins/genetics ; Female ; *Staphylococcal Infections/veterinary/microbiology/epidemiology ; Drug Resistance, Bacterial/genetics ; Anti-Bacterial Agents/pharmacology ; Carrier State/veterinary/microbiology ; Dairying ; Cattle Diseases/microbiology ; }, abstract = {BACKGROUND: Staphylococcus aureus can colonize and infect a variety of animal species. In dairy herds, it is one of the leading causes of mastitis cases. The objective of this study was to characterize the S. aureus isolates recovered from nasal swabs of 249 healthy cows and 21 breeders of 21 dairy farms located in two provinces of Algeria (Tizi Ouzou and Bouira).<br><br>METHODS: The detection of enterotoxin genes was investigated by multiplex PCRs. Resistance of recovered isolates to 8 antimicrobial agents was determined by disc-diffusion method. The slime production and biofilm formation of S. aureus isolates were assessed using congo-red agar (CRA) and microtiter-plate assay. Molecular characterization of selected isolates was carried out by spa-typing and Multi-Locus-Sequence-Typing (MLST).<br><br>RESULTS: S. aureus was detected in 30/249 (12%) and 6/13 (28.6%) of nasal swabs in cows and breeders, respectively, and a total of 72 isolates were recovered from positive samples (59 isolates from cows and 13 from breeders). Twenty-six of these isolates (36.1%) harbored genes encoding for staphylococcal enterotoxins, including 17/59 (28.8%) isolates from cows and 9/13 (69.2%) from breeders. Moreover, 49.1% and 92.3% of isolates from cows and breeders, respectively, showed penicillin resistance. All isolates were considered as methicillin-susceptible (MSSA). Forty-five (76.3%) of the isolates from cows were slime producers and 52 (88.1%) of them had the ability to form biofilm in microtiter plates. Evidence of a possible zoonotic transmission was observed in two farms, since S. aureus isolates recovered in these farms from cows and breeders belonged to the same clonal lineage (CC15-ST15-t084 or CC30-ST34-t2228).<br><br>CONCLUSIONS: Although healthy cows in this study did not harbor methicillin-resistant S. aureus isolates, the nares of healthy cows could be a reservoir of enterotoxigenic and biofilm producing isolates which could have implications in human and animal health.}, }
@article {pmid38849021, year = {2024}, author = {Li, L and Xie, Y and Wang, J and Sun, Q and Gao, M and Li, C}, title = {Biofilm microenvironment-activated multimodal therapy nanoplatform for effective anti-bacterial treatment and wound healing.}, journal = {Acta biomaterialia}, volume = {183}, number = {}, pages = {221-234}, doi = {10.1016/j.actbio.2024.06.002}, pmid = {38849021}, issn = {1878-7568}, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Wound Healing/drug effects ; Animals ; Mice ; *Staphylococcus aureus/drug effects ; *Copper/chemistry/pharmacology ; Nanoparticles/chemistry ; Escherichia coli/drug effects ; Photothermal Therapy ; Humans ; Combined Modality Therapy ; Hydrogen Sulfide/pharmacology/chemistry ; Silicon Dioxide/chemistry/pharmacology ; Cellular Microenvironment/drug effects ; RAW 264.7 Cells ; Macrophages/drug effects/metabolism ; }, abstract = {Antimicrobial drug development faces challenges from bacterial resistance, biofilms, and excessive inflammation. Here, we design an intelligent nanoplatform utilizing mesoporous silica nanoparticles doped with copper ions for loading copper sulfide (DM/Cu[2+]-CuS). The mesoporous silica doped with tetrasulfide bonds responds to the biofilm microenvironment (BME), releasing Cu[2+]ions, CuS along with hydrogen sulfide (H2S) gas. The release of hydrogen sulfide within 72 h reached 793.5 µM, significantly higher than that observed with conventional small molecule donors. H2S induces macrophages polarization towards the M2 phenotype, reducing inflammation and synergistically accelerating endothelial cell proliferation and migration with Cu[2+]ions. In addition, H2S disrupts extracellular DNA within biofilms, synergistically photothermal enhanced peroxidase-like activity of CuS to effectively eradicate biofilms. Remarkably, DM-mediated consumption of endogenous glutathione enhances the anti-biofilm activity of H2S and improves oxygen species (ROS) destruction efficiency. The combination of photothermal therapy (PTT), chemodynamic therapy (CDT), and gas treatment achieves sterilization rates of 99.3 % and 99.6 % against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), respectively, in vitro under 808 nm laser irradiation. Additionally, in vivo experiments demonstrate a significant biosafety and antibacterial potential. In summary, the H2S donor developed in this study exhibits enhanced biocompatibility and controlled release properties. By integrating BME-responsive gas therapy with antibacterial ions, PTT and CDT, a synergistic multimodal strategy is proposed to offer new therapeutic approaches for wound healing. STATEMENT OF SIGNIFICANCE: The advanced DMOS/Cu[2+]-CuS (DMCC) multimodal therapeutic nanoplatform has been developed for the treatment of drug-resistant bacterial wound infections and has exhibited enhanced therapeutic efficacy through the synergistic effects of photothermal therapy, chemodynamic therapy, Cu[2+]ions, and H2S. The DMCC exhibited exceptional biocompatibility and could release CuS, Cu[2+], and H2S in response to elevated concentrations of glutathione within the biofilm microenvironment. H2S effectively disrupted the biofilm structure. Meanwhile, peroxidase activity of CuS combined with GSH-mediated reduction of Cu[2+] to Cu[+] generated abundant hydroxyl radicals under acidic conditions, leading to efficient eradication of pathogenic bacteria. Furthermore, both H2S and Cu[2+] could modulate M2 macrophages polarization and regulate immune microenvironment dynamics. These strategies collectively provided a novel approach for developing antibacterial nanomedical platforms.}, }
@article {pmid38848266, year = {2024}, author = {Loffredo, MR and Casciaro, B and Bellavita, R and Troiano, C and Brancaccio, D and Cappiello, F and Merlino, F and Galdiero, S and Fabrizi, G and Grieco, P and Stella, L and Carotenuto, A and Mangoni, ML}, title = {Strategic Single-Residue Substitution in the Antimicrobial Peptide Esc(1-21) Confers Activity against Staphylococcus aureus, Including Drug-Resistant and Biofilm Phenotype.}, journal = {ACS infectious diseases}, volume = {10}, number = {7}, pages = {2403-2418}, pmid = {38848266}, issn = {2373-8227}, mesh = {*Biofilms/drug effects ; *Staphylococcus aureus/drug effects ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Amino Acid Substitution ; Antimicrobial Peptides/pharmacology/chemistry ; Humans ; Amphibian Proteins/pharmacology/chemistry/genetics ; Antimicrobial Cationic Peptides/pharmacology/chemistry ; Animals ; Drug Resistance, Bacterial ; }, abstract = {Staphylococcus aureus, a bacterium resistant to multiple drugs, is a significant cause of illness and death worldwide. Antimicrobial peptides (AMPs) provide an excellent potential strategy to cope with this threat. Recently, we characterized a derivative of the frog-skin AMP esculentin-1a, Esc(1-21) (1) that is endowed with potent activity against Gram-negative bacteria but poor efficacy against Gram-positive strains. In this study, three analogues of peptide 1 were designed by replacing Gly[8] with α-aminoisobutyric acid (Aib), Pro, and dPro (2-4, respectively). The single substitution Gly[8] → Aib[8] in peptide 2 makes it active against the planktonic form of Gram-positive bacterial strains, especially Staphylococcus aureus, including multidrug-resistant clinical isolates, with an improved biostability without resulting in cytotoxicity to mammalian cells. Moreover, peptide 2 showed a higher antibiofilm activity than peptide 1 against both reference and clinical isolates of S. aureus. Peptide 2 was also able to induce rapid bacterial killing, suggesting a membrane-perturbing mechanism of action. Structural analysis of the most active peptide 2 evidenced that the improved biological activity of peptide 2 is the consequence of a combination of higher biostability, higher α helical content, and ability to reduce membrane fluidity and to adopt a distorted helix, bent in correspondence of Aib[8]. Overall, this study has shown how a strategic single amino acid substitution is sufficient to enlarge the spectrum of activity of the original peptide 1, and improve its biological properties for therapeutic purposes, thus paving the way to optimize AMPs for the development of new broad-spectrum anti-infective agents.}, }
@article {pmid38847888, year = {2024}, author = {Tang, Z and Wang, L and Xiong, Z and Zhu, Y and Zhang, H}, title = {Process optimized for production of iturin A in biofilm reactor by Bacillus velezensis ND.}, journal = {Bioprocess and biosystems engineering}, volume = {47}, number = {7}, pages = {1095-1105}, pmid = {38847888}, issn = {1615-7605}, support = {21366028//Data Center of Management Science, National Natural Science Foundation of China - Peking University/ ; }, mesh = {*Biofilms/growth &amp; development ; *Bioreactors ; *Bacillus/metabolism/growth &amp; development ; Hydrogen-Ion Concentration ; Culture Media ; Fermentation ; Temperature ; Peptides, Cyclic ; }, abstract = {In this research, to provide an optimal growth medium for the production of iturin A, the concentrations of key amino acid precursors were optimized in shake flask cultures using the response surface method. The optimized medium were applied in a biofilm reactor for batch fermentation, resulting in enhanced production of iturin A. On this basis, a step-wise pH control strategy and a combined step-wise pH and temperature control strategy were introduced to further improve the production of iturin A. Finally, the fed-batch fermentation was performed based on combined step-wise pH and temperature control. The titer and productivity of iturin A reached 7.86 ± 0.23 g/L and 65.50 ± 1.92 mg/L/h, respectively, which were 37.65 and 65.20% higher than that before process optimization.}, }
@article {pmid38847838, year = {2024}, author = {Xi, H and Luo, Z and Liu, MF and Chen, Q and Zhu, Q and Yuan, L and Sheng, YY and Zhao, R}, title = {Diclofenac sodium effectively inhibits the biofilm formation of Staphylococcus epidermidis.}, journal = {Archives of microbiology}, volume = {206}, number = {7}, pages = {289}, pmid = {38847838}, issn = {1432-072X}, support = {2021B723//Jiangxi University of Traditional Chinese Medicine/ ; 82260085//National Social Science Fund of China/ ; }, mesh = {*Biofilms/drug effects ; *Staphylococcus epidermidis/drug effects/physiology ; *Diclofenac/pharmacology ; *Anti-Bacterial Agents/pharmacology ; Microbial Sensitivity Tests ; Anti-Inflammatory Agents, Non-Steroidal/pharmacology ; Bacterial Adhesion/drug effects ; Humans ; Polysaccharides, Bacterial/metabolism ; Bacterial Proteins/genetics/metabolism ; Staphylococcal Infections/microbiology/drug therapy ; Gene Expression Regulation, Bacterial/drug effects ; }, abstract = {Staphylococcus epidermidis is an opportunistic pathogen commonly implicated in medical device-related infections. Its propensity to form biofilms not only leads to chronic infections but also exacerbates the issue of antibiotic resistance, necessitating high-dose antimicrobial treatments. In this study, we explored the use of diclofenac sodium, a non-steroidal anti-inflammatory drug, as an anti-biofilm agent against S. epidermidis. In this study, crystal violet staining and confocal laser scanning microscope analysis showed that diclofenac sodium, at subinhibitory concentration (0.4 mM), significantly inhibited biofilm formation in both methicillin-susceptible and methicillin-resistant S. epidermidis isolates. MTT assays demonstrated that 0.4 mM diclofenac sodium reduced the metabolic activity of biofilms by 25.21-49.01% compared to untreated controls. Additionally, the treatment of diclofenac sodium resulted in a significant decrease (56.01-65.67%) in initial bacterial adhesion, a crucial early phase of biofilm development. Notably, diclofenac sodium decreased the production of polysaccharide intercellular adhesin (PIA), a key component of the S. epidermidis biofilm matrix, in a dose-dependent manner. Real-time quantitative PCR analysis revealed that diclofenac sodium treatment downregulated biofilm-associated genes icaA, fnbA, and sigB and upregulated negative regulatory genes icaR and luxS, providing potential mechanistic insights. These findings indicate that diclofenac sodium inhibits S. epidermidis biofilm formation by affecting initial bacterial adhesion and the PIA synthesis. This underscores the potential of diclofenac sodium as a supplementary antimicrobial agent in combating staphylococcal biofilm-associated infections.}, }
@article {pmid38847000, year = {2024}, author = {Fang, L and Zhang, Y and Cheng, L and Zheng, H and Wang, Y and Qin, L and Cai, Y and Cheng, L and Zhou, W and Liu, F and Wang, S}, title = {Silica nanoparticles containing nano-silver and chlorhexidine to suppress Porphyromonas gingivalis biofilm and modulate multispecies biofilms toward healthy tendency.}, journal = {Journal of oral microbiology}, volume = {16}, number = {1}, pages = {2361403}, pmid = {38847000}, issn = {2000-2297}, abstract = {OBJECTIVES: This research first investigated the effect of mesoporous silica nanoparticles (nMS) carrying chlorhexidine and silver (nMS-nAg-Chx) on periodontitis-related biofilms. This study aimed to investigate (1) the antibacterial activity on Porphyromonas gingivalis (P. gingivalis) biofilm; (2) the suppressing effect on virulence of P. gingivalis biofilm; (3) the regulating effect on periodontitis-related multispecies biofilm.<br><br>METHODS: Silver nanoparticles (nAg) and chlorhexidine (Chx) were co-loaded into nMS to form nMS-nAg-Chx. Inhibitory zone test and minimum inhibitory concentration (MIC) against P. gingivalis were tested. Growth curves, crystal violet (CV) staining, live/dead staining and scanning electron microscopy (SEM) observation were performed. Biofilm virulence was assessed. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and Quantitative Real Time-PCR (qPCR) were performed to validate the activity and composition changes of multispecies biofilm (P. gingivalis, Streptococcus gordonii and Streptococcus sanguinis).<br><br>RESULTS: nMS-nAg-Chx inhibited P. gingivalis biofilm dose-dependently (p<0.05), with MIC of 18.75&#x2009;&#xb5;g/mL. There were fewer live bacteria, less biomass and less virulence in nMS-nAg-Chx groups (p<0.05). nMS-nAg-Chx inhibited and modified periodontitis-related biofilms. The proportion of pathogenic bacteria decreased from 16.08 to 1.07% and that of helpful bacteria increased from 82.65 to 94.31% in 25&#x2009;&#x3bc;g/mL nMS-nAg-Chx group for 72&#x2009;h.<br><br>CONCLUSIONS: nMS-nAg-Chx inhibited P. gingivalis growth, decreased biofilm virulence and modulated periodontitis-related multispecies biofilms toward healthy tendency. pH-sensitive nMS-nAg-Chx inhibit the pathogens and regulate oral microecology, showing great potential in periodontitis adjunctive therapy.}, }
@article {pmid38846101, year = {2024}, author = {Peran, JE and Salvador-Reyes, LA}, title = {Modified oxylipins as inhibitors of biofilm formation in Staphylococcus epidermidis.}, journal = {Frontiers in pharmacology}, volume = {15}, number = {}, pages = {1379643}, pmid = {38846101}, issn = {1663-9812}, abstract = {New approaches to combating microbial drug resistance are being sought, with the discovery of biofilm inhibitors considered as alternative arsenal for treating infections. Natural products have been at the forefront of antimicrobial discovery and serve as inspiration for the design of new antibiotics. We probed the potency, selectivity, and mechanism of anti-biofilm activity of modified oxylipins inspired by the marine natural product turneroic acid. Structure-activity relationship (SAR) evaluation revealed the importance of the trans-epoxide moiety, regardless of the position, for inhibiting biofilm formation. trans-12,13-epoxyoctadecanoic acid (1) and trans-9,10 epoxyoctadecanoic acid (4) selectively target the early stage of biofilm formation, with no effect on planktonic cells. These compounds interrupt the formation of a protective polysaccharide barrier by significantly upregulating the ica operon's transcriptional repressor. This was corroborated by docking experiment with SarA and scanning electron micrographs showing reduced biofilm aggregates and the absence of thread-like structures of extrapolymeric substances. In silico evaluation revealed that 1 and 4 can interfere with the AgrA-mediated communication language in Staphylococci, typical to the diffusible signal factor (DSF) capacity of lipophilic chains.}, }
@article {pmid38845852, year = {2024}, author = {Li, X and Tao, M and Quan, L and Zhang, H and Xin, Y and Wu, X and Fang, X and Fan, J and Tian, X and Wang, X and Wen, L and Yu, T and Ao, Q}, title = {Preparation and evaluation of decellularized epineurium as an anti-adhesive biofilm in peripheral nerve repair.}, journal = {Regenerative biomaterials}, volume = {11}, number = {}, pages = {rbae054}, pmid = {38845852}, issn = {2056-3418}, abstract = {Following peripheral nerve anastomosis, the anastomotic site is prone to adhesions with surrounding tissues, consequently impacting the effectiveness of nerve repair. This study explores the development and efficacy of a decellularized epineurium as an anti-adhesive biofilm in peripheral nerve repair. Firstly, the entire epineurium was extracted from fresh porcine sciatic nerves, followed by a decellularization process. The decellularization efficiency was then thoroughly assessed. Subsequently, the decellularized epineurium underwent proteomic analysis to determine the remaining bioactive components. To ensure biosafety, the decellularized epineurium underwent cytotoxicity assays, hemolysis tests, cell affinity assays, and assessments of the immune response following subcutaneous implantation. Finally, the functionality of the biofilm was determined using a sciatic nerve transection and anastomosis model in rats. The result indicated that the decellularization process effectively removed cellular components from the epineurium while preserving a number of bioactive molecules, and this decellularized epineurium was effective in preventing adhesion while promoting nerve repairment and functional recovery. In conclusion, the decellularized epineurium represents a novel and promising anti-adhesion biofilm for enhancing surgical outcomes of peripheral nerve repair.}, }
@article {pmid38845571, year = {2024}, author = {Schultz, C and Zopf, D and Holzinger, A and Silge, A and Meyer-Zedler, T and Schmitt, M and Wichard, T and Popp, J}, title = {Raman Spectral Analysis in the CHx-Stretching Region as a Guiding Beacon for Non-Targeted, Disruption-Free Monitoring of Germination and Biofilm Formation in the Green Seaweed Ulva.}, journal = {Chemphyschem : a European journal of chemical physics and physical chemistry}, volume = {25}, number = {17}, pages = {e202400173}, doi = {10.1002/cphc.202400173}, pmid = {38845571}, issn = {1439-7641}, support = {SFB 1127//Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)/ ; EXC 2051, Project-ID 390713860//Germany's Excellence Strategy/ ; 10.55776/P34181//Austrian Science Fund (FWF)/ ; }, mesh = {*Spectrum Analysis, Raman ; *Ulva ; *Biofilms ; Seaweed/microbiology ; }, abstract = {Raman spectroscopy was used to study the complex interactions and morphogenesis of the green seaweed Ulva (Chlorophyta) and its associated bacteria under controlled conditions in a reductionist model system. Integrating multiple imaging techniques contributes to a more comprehensive understanding of these biological processes. Therefore, Raman spectroscopy was introduced as a non-invasive, label-free tool for examining chemical information of the tripartite community Ulva mutabilis-Roseovarius sp.-Maribacter sp. The study explored cell differentiation, cell wall protrusion, and bacterial-macroalgae interactions of intact algal thalli. Using Raman spectroscopy, the analysis of the CHx-stretching wavenumber region distinguished spatial regions in Ulva germination and cellular malformations under axenic conditions and upon inoculation with a specific bacterium in bipartite communities. The spectral information was used to guide in-depth analyses within the fingerprint region and to identify substance classes such as proteins, lipids, and polysaccharides, including evidence for ulvan found in cell wall protrusions.}, }
@article {pmid38845374, year = {2024}, author = {Bhowmik, A and Chakraborty, S and Rohit, A and Chauhan, A}, title = {Transcriptomic responses of extensively drug resistant Klebsiella pneumoniae to N-acetyl cysteine reveals suppression of major biogenesis pathways leading to bacterial killing and biofilm eradication.}, journal = {Journal of applied microbiology}, volume = {135}, number = {6}, pages = {}, doi = {10.1093/jambio/lxae136}, pmid = {38845374}, issn = {1365-2672}, support = {//UGC/ ; F.30-487/2019//BSR/ ; //DST/ ; OMI/20/2020-ECD-1//ICMR/ ; CRG/2021/001974//SERB/ ; //Department of Biotechnology/ ; }, mesh = {*Biofilms/drug effects ; *Klebsiella pneumoniae/drug effects/genetics ; *Anti-Bacterial Agents/pharmacology ; *Acetylcysteine/pharmacology ; Humans ; *Drug Resistance, Multiple, Bacterial/genetics ; *Transcriptome ; Klebsiella Infections/microbiology ; Microbial Sensitivity Tests ; India ; Bacterial Proteins/genetics/metabolism ; }, abstract = {AIMS: Carbapenemase-producing Klebsiella pneumoniae is categorized as a "critical global priority-one" pathogen by WHO and new and efficient treatment options are warranted. This study aims to assess the antibacterial and antibiofilm potential of N-acetyl cysteine (NAC), against clinical isolates of extensively drug resistant (XDR) K. pneumoniae and elucidate the mechanism of killing.<br><br>METHODS AND RESULTS: XDR-K. pneumoniae were isolated from patients admitted to Madras Medical Mission Hospital, India. Antibiofilm activity of NAC was checked using in vitro continuous flow model and RNA sequencing was done using Illumina Novoseq. Data quality was checked using FastQC and MultiQC software. Our findings revealed that NAC at a concentration of 100&#x2009;mg/ml was safe, and could inhibit the growth and completely eradicate mature biofilms of all XDR-K. pneumoniae isolates. Transcriptomic responses in XDR-K. pneumoniae to NAC showed significant downregulation of the genes associated with crucial biogenesis pathways, including electron transport chain and oxidoreductase activity besides a specific cluster of genes linked to ribosomal proteins.<br><br>CONCLUSIONS: Our results indicate that NAC kills the XDR- K. pneumoniae clinical isolates by shutting the overall metabolism and, hence, successfully eradicate in vitro biofilms formed on catheters.}, }
@article {pmid38844261, year = {2024}, author = {Ronish, LA and Biswas, B and Bauer, RM and Jacob, ME and Piepenbrink, KH}, title = {The role of extracellular structures in Clostridioides difficile biofilm formation.}, journal = {Anaerobe}, volume = {88}, number = {}, pages = {102873}, doi = {10.1016/j.anaerobe.2024.102873}, pmid = {38844261}, issn = {1095-8274}, support = {T32 GM107001/GM/NIGMS NIH HHS/United States ; T32 GM136593/GM/NIGMS NIH HHS/United States ; }, mesh = {*Biofilms/growth &amp; development/drug effects ; *Clostridioides difficile/physiology/growth &amp; development/genetics ; Humans ; *Clostridium Infections/microbiology ; Anti-Bacterial Agents/pharmacology ; }, abstract = {C. difficile infection (CDI) is a costly and increasing burden on the healthcare systems of many developed countries due to the high rates of nosocomial infections. Despite the availability of several antibiotics with high response rates, effective treatment is hampered by recurrent infections. One potential mechanism for recurrence is the existence of C. difficile biofilms in the gut which persist through the course of antibiotics. In this review, we describe current developments in understanding the molecular mechanisms by which C. difficile biofilms form and are stabilized through extracellular biomolecular interactions.}, }
@article {pmid38844237, year = {2024}, author = {Papale, M and Fazi, S and Severini, M and Scarinci, R and Dell'Acqua, O and Azzaro, M and Venuti, V and Fazio, B and Fazio, E and Crupi, V and Irrera, A and Rizzo, C and Giudice, AL and Caruso, G}, title = {Structural properties and microbial diversity of the biofilm colonizing plastic substrates in Terra Nova Bay (Antarctica).}, journal = {The Science of the total environment}, volume = {943}, number = {}, pages = {173773}, doi = {10.1016/j.scitotenv.2024.173773}, pmid = {38844237}, issn = {1879-1026}, mesh = {*Biofilms ; Antarctic Regions ; *Plastics ; *Bays/microbiology ; *Microbiota ; RNA, Ribosomal, 16S ; Bacteria/classification ; Biofouling ; }, abstract = {Microbial colonization on plastic polymers has been extensively explored, however the temporal dynamics of biofilm community in Antarctic environments are almost unknown. As a contribute to fill this knowledge gap, the structural characteristics and microbial diversity of the biofilm associated with polyvinyl chloride (PVC) and polyethylene (PE) panels submerged at 5 m of depth and collected after 3, 9 and 12 months were investigated in four coastal sites of the Ross Sea. Additional panels placed at 5 and 20 m were retrieved after 12 months. Chemical characterization was performed by FTIR-ATR and Raman (through Surface-Enhanced Raman Scattering, SERS) spectroscopy. Bacterial community composition was quantified at a single cell level by Catalyzed Reporter Deposition Fluorescence In Situ Hybridization (CARD-FISH) and Confocal Laser Scanning Microscopy (CLSM); microbial diversity was assessed by 16S rRNA gene sequencing. This multidisciplinary approach has provided new insights into microbial community dynamics during biofouling process, shedding light on the biofilm diversity and temporal succession on plastic substrates in the Ross Sea. Significant differences between free-living and microbial biofilm communities were found, with a more consolidated and structured community composition on PVC compared to PE. Spectral features ascribable to tyrosine, polysaccharides, nucleic acids and lipids characterized the PVC-associated biofilms. Pseudomonadota (among Gamma-proteobacteria) and Alpha-proteobacteria dominated the microbial biofilm community. Interestingly, in Road Bay, close to the Italian "Mario Zucchelli" research station, the biofilm growth - already observed during summer season, after 3 months of submersion - continued afterwards leading to a massive microbial abundance at the end of winter (after 12 months). After 3 months, higher percentages of Gamma-proteobacteria in Road Bay than in the not-impacted site were found. These observations lead us to hypothesize that in this site microbial fouling developed during the first 3 months could serve as a starter pioneering community stimulating the successive growth during winter.}, }
@article {pmid38843647, year = {2024}, author = {Wang, C and El-Telbany, M and Lin, Y and Zhao, J and Maung, AT and Abdelaziz, MNS and Nakayama, M and Masuda, Y and Honjoh, KI and Miyamoto, T}, title = {Identification of Enterococcus spp. from food sources by matrix-assisted laser desorption ionization-time of flight mass spectrometry and characterization of virulence factors, antibiotic resistance, and biofilm formation.}, journal = {International journal of food microbiology}, volume = {420}, number = {}, pages = {110768}, doi = {10.1016/j.ijfoodmicro.2024.110768}, pmid = {38843647}, issn = {1879-3460}, mesh = {*Biofilms/growth &amp; development ; *Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ; *Enterococcus/genetics/pathogenicity/drug effects/isolation &amp; purification ; *Virulence Factors/genetics ; Animals ; Egypt ; *Food Microbiology ; *Anti-Bacterial Agents/pharmacology ; Vegetables/microbiology ; Japan ; Chickens ; Milk/microbiology ; Feces/microbiology ; Microbial Sensitivity Tests ; Drug Resistance, Bacterial ; Drug Resistance, Multiple, Bacterial ; Food Contamination/analysis ; }, abstract = {The continuous detection of multi-drug-resistant enterococci in food source environments has aroused widespread concern. In this study, 198 samples from chicken products, animal feces, raw milk, and vegetables were collected in Japan and Egypt to investigate the prevalence of enterococci and virulence characterization. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was employed for species identification and taxonomic analysis of the isolates. The results showed that the rates of most virulence genes (efaA, gelE, asa1, ace, and hyl) in the Japanese isolates were slightly higher than those in the Egyptian isolates. The rate of efaA was the highest (94.9 %) among seven virulence genes detected, but the cylA gene was not detected in all isolates, which was in accordance with γ-type hemolysis phenotype. In Enterococcus faecalis, the rate of kanamycin-resistant strains was the highest (84.75 %) among the antibiotics tested. Moreover, 78 % of E. faecalis strains exhibited multi-drug resistance. Four moderately vancomycin-resistant strains were found in Egyptian isolates, but none were found in Japanese isolates. MALDI-TOF MS analysis correctly identified 98.5 % (68/69) of the Enterococcus isolates. In the principal component analysis dendrogram, strains isolated from the same region with the same virulence characteristics and similar biofilm-forming abilities were characterized by clustered distribution in different clusters. This finding highlights the potential of MALDI-TOF MS for classifying E. faecalis strains from food sources.}, }
@article {pmid38843627, year = {2024}, author = {Zhou, L and Wu, F and Lai, Y and Zhao, B and Zhang, W and Rittmann, BE}, title = {Cooperation and competition between denitrification and chromate reduction in a hydrogen-based membrane biofilm reactor.}, journal = {Water research}, volume = {259}, number = {}, pages = {121870}, doi = {10.1016/j.watres.2024.121870}, pmid = {38843627}, issn = {1879-2448}, mesh = {*Chromates/metabolism ; *Denitrification ; *Biofilms ; *Bioreactors ; *Hydrogen/metabolism ; *Oxidation-Reduction ; Nitrates/metabolism ; Membranes, Artificial ; RNA, Ribosomal, 16S ; }, abstract = {Competition and cooperation between denitrification and Cr(VI) reduction in a H2-based membrane biofilm reactor (H2-MBfR) were documented over 55 days of continuous operation. When nitrate (5 mg N/L) and chromate (0.5 mg Cr/L) were fed together, the H2-MBfR maintained approximately 100 % nitrate removal and 60 % chromate Cr(VI) removal, which means that nitrate outcompeted Cr(VI) for electrons from H2 oxidation. Removing nitrate from the influent led to an immediate increase in Cr(VI) removal (to 92 %), but Cr(VI) removal gradually deteriorated, with the removal ratio dropping to 14 % after five days. Cr(VI) removal resumed once nitrate was again added to the influent. 16S rDNA analyses showed that bacteria able to carry out H2-based denitrification and Cr(VI) reduction were in similar abundances throughout the experiment, but gene expression for Cr(VI)-reduction and export shifted. Functional genes encoding for energy-consuming chromate export (encoded by ChrA) as a means of bacterial resistance to toxicity were more abundant than genes encoding for the energy producing Cr(VI) respiration via the chromate reductase ChrR-NdFr. Thus, Cr(VI) transport and resistance to Cr(VI) toxicity depended on H2-based denitrification to supply energy. With Cr(VI) being exported from the cells, Cr(VI) reduction to Cr(III) was sustained. Thus, cooperation among H2-based denitrification, Cr(VI) export, and Cr(VI) reduction led to sustained Cr(VI) removal in the presence of nitrate, even though Cr(VI) reduction was at a competitive disadvantage for utilizing electrons from H2 oxidation.}, }
@article {pmid38841057, year = {2024}, author = {Afrasiabi, S and Partoazar, A}, title = {Targeting bacterial biofilm-related genes with nanoparticle-based strategies.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1387114}, pmid = {38841057}, issn = {1664-302X}, abstract = {Persistent infection caused by biofilm is an urgent in medicine that should be tackled by new alternative strategies. Low efficiency of classical treatments and antibiotic resistance are the main concerns of the persistent infection due to biofilm formation which increases the risk of morbidity and mortality. The gene expression patterns in biofilm cells differed from those in planktonic cells. One of the promising approaches against biofilms is nanoparticle (NP)-based therapy in which NPs with multiple mechanisms hinder the resistance of bacterial cells in planktonic or biofilm forms. For instance, NPs such as silver (Ag), zinc oxide (ZnO), titanium dioxide (TiO2), copper oxide (Cu), and iron oxide (Fe3O4) through the different strategies interfere with gene expression of bacteria associated with biofilm. The NPs can penetrate into the biofilm structure and affect the expression of efflux pump, quorum-sensing, and adhesion-related genes, which lead to inhibit the biofilm formation or development. Therefore, understanding and targeting of the genes and molecular basis of bacterial biofilm by NPs point to therapeutic targets that make possible control of biofilm infections. In parallel, the possible impact of NPs on the environment and their cytotoxicity should be avoided through controlled exposure and safety assessments. This study focuses on the biofilm-related genes that are potential targets for the inhibition of bacterial biofilms with highly effective NPs, especially metal or metal oxide NPs.}, }
@article {pmid38841053, year = {2024}, author = {Xie, H and Zhang, R and Li, Z and Guo, R and Li, J and Fu, Q and Wang, X and Zhou, Y}, title = {Endogenous Type I-C CRISPR-Cas system of Streptococcus equi subsp. zooepidemicus promotes biofilm formation and pathogenicity.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1417993}, pmid = {38841053}, issn = {1664-302X}, abstract = {Streptococcus equi subsp. zooepidemicus (SEZ) is a significant zoonotic pathogen that causes septicemia, meningitis, and mastitis in domestic animals. Recent reports have highlighted high-mortality outbreaks among swine in the United States. Traditionally recognized for its adaptive immune functions, the CRISPR-Cas system has also been implicated in gene regulation, bacterial pathophysiology, virulence, and evolution. The Type I-C CRISPR-Cas system, which is prevalent in SEZ isolates, appears to play a pivotal role in regulating the pathogenicity of SEZ. By constructing a Cas3 mutant strain (ΔCas3) and a CRISPR-deficient strain (ΔCRISPR), we demonstrated that this system significantly promotes biofilm formation and cell adhesion. However, the deficiency in the CRISPR-Cas system did not affect bacterial morphology or capsule production. In vitro studies showed that the CRISPR-Cas system enhances pro-inflammatory responses in RAW264.7 cells. The ΔCas3 and ΔCRISPR mutant strains exhibited reduced mortality rates in mice, accompanied by a decreased bacterial load in specific organs. RNA-seq analysis revealed distinct expression patterns in both mutant strains, with ΔCas3 displaying a broader range of differentially expressed genes, which accounted for over 70% of the differential genes observed in ΔCRISPR. These genes were predominantly linked to lipid metabolism, the ABC transport system, signal transduction, and quorum sensing. These findings enhance our understanding of the complex role of the CRISPR-Cas system in SEZ pathogenesis and provide valuable insights for developing innovative therapeutic strategies to combat infections.}, }
@article {pmid38840467, year = {2024}, author = {Egbule, OS and Konye, OP and Iweriebor, BC}, title = {Assessment of Biofilm Forming Capability and Antibiotic Resistance in Proteus mirabilis Colonizing Indwelling Catheter.}, journal = {Pakistan journal of biological sciences : PJBS}, volume = {27}, number = {5}, pages = {268-275}, doi = {10.3923/pjbs.2024.268.275}, pmid = {38840467}, issn = {1812-5735}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Proteus mirabilis/drug effects/genetics/isolation &amp; purification ; *Catheters, Indwelling/microbiology/adverse effects ; Humans ; *Anti-Bacterial Agents/pharmacology/therapeutic use ; *Microbial Sensitivity Tests ; Urinary Tract Infections/microbiology/drug therapy/diagnosis ; Plasmids/genetics ; Urinary Catheters/microbiology/adverse effects ; Drug Resistance, Bacterial ; Proteus Infections/microbiology/drug therapy ; Catheter-Related Infections/microbiology/diagnosis/drug therapy ; Female ; Male ; Drug Resistance, Multiple, Bacterial/genetics ; }, abstract = {Background and Objective: Urinary tract infections from the use of an indwelling urinary catheter are one of the most common infections caused by Proteus mirabilis. Due to their biofilm-producing capacity and the increasing antimicrobial resistance in this microorganism, this study aimed to determine the prevalence, biofilm-producing capacity, antimicrobial resistance patterns, multidrug resistance and plasmid mediated resistance of the recovered isolates. Materials and Methods: A total of 50 urinary samples were collected from May to August, 2018 from patients on indwelling urinary catheters. Using routine microbiological and biochemical methods, 37 P. mirabilis were isolated. Biofilm forming capability was determined among the isolates using the tube method while antimicrobial susceptibility and plasmid curing were also performed. Results: All isolates were biofilm producers with 17(46%) being moderate producers while 20(54%) were strong biofilm formers. The study isolates exhibited a high resistance rate to empiric antibiotics, including ceftazidime (75.8%), cefuroxime (54.5%), ampicillin (69.7%) and amoxicillin-clavulanic acid (51.5%). Low resistance was seen in the fluoroquinolones, gentamicin and nitrofurantoin. Plasmid curing experiment revealed that most isolates lost their resistance indicating that resistance was borne on plasmids. Plasmid carriage is likely the reason for the high MDR rate of 56.8% observed. Conclusion: These findings necessitate the provision of infection control programs which will guide and implement policies.}, }
@article {pmid38838630, year = {2024}, author = {Shi, Q and Yu, T and de Vries, J and Peterson, BW and Ren, Y and Wu, R and Liu, J and Busscher, HJ and van der Mei, HC}, title = {Nano-architectonics of Pt single-atoms and differently-sized nanoparticles supported by manganese-oxide nanosheets and impact on catalytic and anti-biofilm activities.}, journal = {Journal of colloid and interface science}, volume = {672}, number = {}, pages = {224-235}, doi = {10.1016/j.jcis.2024.05.241}, pmid = {38838630}, issn = {1095-7103}, abstract = {Hybrid-nanozymes are promising in various applications, but comprehensive comparison of hybrid-nanozymes composed of single-atoms or nanoparticles on the same support has never been made. Here, manganese-oxide nanosheets were loaded with Pt-single-atoms or differently-sized nanoparticles and their oxidase- and-peroxidase activities compared. High-resolution Transmission-Electron-Microscopy and corresponding Fast Fourier Transform imaging showed that Pt-nanoparticles (1.5 nm diameter) had no clear (111) crystal-planes, while larger nanoparticles had clear (111) crystal-planes. X-ray Photo-electron Spectroscopy demonstrated that unloaded nanosheets were composed of MnO2 with a high number of oxygen vacancies (Vo/Mn 0.4). Loading with 7.0 nm Pt-nanoparticles induced a change to Mn2O3, while loading with 1.5 nm nanoparticles increased the number of vacancies (Vo/Mn 1.2). Nanosheets loaded with 3.0 nm Pt-nanoparticles possessed similarly high catalytic activities as Pt-single-atoms. However, loading with 1.5 nm or 7.0 nm Pt-nanoparticles yielded lower catalytic activities. A model is proposed explaining the low catalytic activity of under- and over-sized Pt-nanoparticles as compared with intermediately-sized (3.0 nm) Pt-nanoparticles and single-atoms. Herewith, catalytic activities of hybrid-nanozymes composed of single-atoms and intermediately-sized nanoparticles are put a par, as confirmed here with respect to bacterial biofilm eradication. This conclusion facilitates a balanced choice between using Pt-single-atoms or nanoparticles in further development and application of hybrid-nanozymes.}, }
@article {pmid38838607, year = {2024}, author = {Gholipour, S and Nikaeen, M and Mohammadi, F and Rabbani, D}, title = {Antibiotic resistance pattern of waterborne causative agents of healthcare-associated infections: A call for biofilm control in hospital water systems.}, journal = {Journal of infection and public health}, volume = {17}, number = {7}, pages = {102469}, doi = {10.1016/j.jiph.2024.102469}, pmid = {38838607}, issn = {1876-035X}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Cross Infection/microbiology ; Humans ; *Hospitals ; Iran/epidemiology ; Drug Resistance, Bacterial/genetics ; Water Microbiology ; Bacteria/drug effects/genetics/isolation &amp; purification/classification ; Anti-Bacterial Agents/pharmacology ; }, abstract = {BACKGROUND: In recent years, the global spread of antimicrobial resistance has become a concerning issue, often referred to as a "silent pandemic". Healthcare-associated infections (HAIs) caused by antibiotic-resistant bacteria (ARB) are a recurring problem, with some originating from waterborne route. The study aimed to investigate the presence of clinically relevant opportunistic bacteria and antibiotic resistance genes (ARGs) in hospital water distribution systems (WDSs).<br><br>METHODS: Water and biofilm samples (n&#xa0;=&#xa0;192) were collected from nine hospitals in Isfahan and Kashan, located in central Iran, between May 2022 and June 2023. The samples were analyzed to determine the presence and quantities of opportunistic bacteria and ARGs using cultural and molecular methods.<br><br>RESULTS: Staphylococcus spp. were highly detected in WDS samples (90 isolates), with 33&#xa0;% of them harboring mecA gene. However, the occurrences of E. coli (1 isolate), Acinetobacter baumannii (3 isolates), and Pseudomonas aeruginosa (14 isolates) were low. Moreover, several Gram-negative bacteria containing ARGs were identified in the samples, mainly belonging to Stenotrophomonas, Sphingomonas and Brevundimonas genera. Various ARGs, as well as intI1, were found in hospital WDSs (ranging from 14&#xa0;% to 60&#xa0;%), with higher occurrences in the biofilm samples.<br><br>CONCLUSION: Our results underscore the importance of biofilms in water taps as hotspots for the dissemination of opportunistic bacteria and ARG within hospital environments. The identification of multiple opportunistic bacteria and ARGs raises concerns about the potential exposure and acquisition of HAIs, emphasizing the need for proactive measures, particularly in controlling biofilms, to mitigate infection risks in healthcare settings.}, }
@article {pmid38837404, year = {2024}, author = {Furtado, KL and Plott, L and Markovetz, M and Powers, D and Wang, H and Hill, DB and Papin, J and Allbritton, NL and Tamayo, R}, title = {Clostridioides difficile-mucus interactions encompass shifts in gene expression, metabolism, and biofilm formation.}, journal = {mSphere}, volume = {9}, number = {6}, pages = {e0008124}, pmid = {38837404}, issn = {2379-5042}, support = {R01-GM147257//HHS | National Institutes of Health (NIH)/ ; R01 GM147257/GM/NIGMS NIH HHS/United States ; R01 DK120606/DK/NIDDK NIH HHS/United States ; R01-AI54242//HHS | National Institutes of Health (NIH)/ ; R01-AI143638//HHS | National Institutes of Health (NIH)/ ; P30-DK065988//HHS | National Institutes of Health (NIH)/ ; R01 AI143638/AI/NIAID NIH HHS/United States ; HILL20Y2-OUT//Cystic Fibrosis Foundation (CFF)/ ; P30 DK065988/DK/NIDDK NIH HHS/United States ; R01-DK120606//HHS | National Institutes of Health (NIH)/ ; }, mesh = {*Clostridioides difficile/genetics/physiology/metabolism ; *Biofilms/growth &amp; development ; Humans ; *Mucus/microbiology/metabolism ; *Gene Expression Regulation, Bacterial ; Epithelial Cells/microbiology ; Intestinal Mucosa/microbiology/metabolism ; Clostridium Infections/microbiology ; }, abstract = {UNLABELLED: In a healthy colon, the stratified mucus layer serves as a crucial innate immune barrier to protect the epithelium from microbes. Mucins are complex glycoproteins that serve as a nutrient source for resident microflora and can be exploited by pathogens. We aimed to understand how the intestinal pathogen, Clostridioides difficile, independently uses or manipulates mucus to its benefit, without contributions from members of the microbiota. Using a 2-D primary human intestinal epithelial cell model to generate physiologic mucus, we assessed C. difficile-mucus interactions through growth assays, RNA-Seq, biophysical characterization of mucus, and contextualized metabolic modeling. We found that host-derived mucus promotes C. difficile growth both in vitro and in an infection model. RNA-Seq revealed significant upregulation of genes related to central metabolism in response to mucus, including genes involved in sugar uptake, the Wood-Ljungdahl pathway, and the glycine cleavage system. In addition, we identified differential expression of genes related to sensing and transcriptional control. Analysis of mutants with deletions in highly upregulated genes reflected the complexity of C. difficile-mucus interactions, with potential interplay between sensing and growth. Mucus also stimulated biofilm formation in vitro, which may in turn alter the viscoelastic properties of mucus. Context-specific metabolic modeling confirmed differential metabolism and the predicted importance of enzymes related to serine and glycine catabolism with mucus. Subsequent growth experiments supported these findings, indicating mucus is an important source of serine. Our results better define responses of C. difficile to human gastrointestinal mucus and highlight flexibility in metabolism that may influence pathogenesis.<br><br>IMPORTANCE: Clostridioides difficile results in upward of 250,000 infections and 12,000 deaths annually in the United States. Community-acquired infections continue to rise, and recurrent disease is common, emphasizing a vital need to understand C. difficile pathogenesis. C. difficile undoubtedly interacts with colonic mucus, but the extent to which the pathogen can independently respond to and take advantage of this niche has not been explored extensively. Moreover, the metabolic complexity of C. difficile remains poorly understood but likely impacts its capacity to grow and persist in the host. Here, we demonstrate that C. difficile uses native colonic mucus for growth, indicating C. difficile possesses mechanisms to exploit the mucosal niche. Furthermore, mucus induces metabolic shifts and biofilm formation in C. difficile, which has potential ramifications for intestinal colonization. Overall, our work is crucial to better understand the dynamics of C. difficile-mucus interactions in the context of the human gut.}, }
@article {pmid38834562, year = {2024}, author = {Shakeel, M and Abbas, N and Rehman, MJU and Alshammari, FS and Al-Yaari, A}, title = {Lie symmetry analysis and solitary wave solution of biofilm model Allen-Cahn.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {12844}, pmid = {38834562}, issn = {2045-2322}, abstract = {The investigation presented in this study delves into the analysis of Lie symmetries for the bistable Allen-Cahn (BAC) equation with a quartic potential, specifically applied to the biofilm model. By employing the Lie symmetry method, we have acquired the Lie infinitesimal generators for the considered model. Using a transformation method, the nonlinear partial differential equations (NPDEs) are converted into various nonlinear ordinary differential equations (NLODEs), providing the numerous closed-form solitary wave solutions. The obtained solutions manifest in various forms including dark, bright, kink, anti-kink, and periodic types using diverse strategies. To enhance the physical interpretation, the study presents 3D, 2D, and contour plots of the acquired solutions. Every graph's wave-like structure contains information about the structural behaviour of the bacteria that build biofilms on surfaces where rectangles have different densities. This analysis enhances comprehension of the complex dynamics present in areas like fluid dynamics, fiber optics, biology, ocean physics, coastal engineering, and nonlinear complex physical systems.}, }
@article {pmid38833832, year = {2024}, author = {Xu, Z and Li, Y and Xu, A and Soteyome, T and Yuan, L and Ma, Q and Seneviratne, G and Li, X and Liu, J}, title = {Cell-wall-anchored proteins affect invasive host colonization and biofilm formation in Staphylococcus aureus.}, journal = {Microbiological research}, volume = {285}, number = {}, pages = {127782}, doi = {10.1016/j.micres.2024.127782}, pmid = {38833832}, issn = {1618-0623}, mesh = {*Biofilms/growth &amp; development ; *Staphylococcus aureus/physiology/genetics ; Humans ; *Staphylococcal Infections/microbiology ; *Bacterial Proteins/metabolism/genetics ; *Cell Wall/metabolism ; *Bacterial Adhesion ; Animals ; Peptidoglycan/metabolism ; }, abstract = {As a major human and animal pathogen, Staphylococcus aureus can attach to medical implants (abiotic surface) or host tissues (biotic surface), and further establish robust biofilms which enhances resistance and persistence to host immune system and antibiotics. Cell-wall-anchored proteins (CWAPs) covalently link to peptidoglycan, and largely facilitate the colonization of S. aureus on various surfaces (including adhesion and biofilm formation) and invasion into host cells (including adhesion, immune evasion, iron acquisition and biofilm formation). During biofilm formation, CWAPs function in adhesion, aggregation, collagen-like fiber network formation, and consortia formation. In this review, we firstly focus on the structural features of CWAPs, including their intracellular function and interactions with host cells, as well as the functions and ligand binding of CWAPs in different stages of S. aureus biofilm formation. Then, the roles of CWAPs in different biofilm processes with regards in development of therapeutic approaches are clarified, followed by the association between CWAPs genes and clonal lineages. By touching upon these aspects, we hope to provide comprehensive knowledge and clearer understanding on the CWAPs of S. aureus and their roles in biofilm formation, which may further aid in prevention and treatment infection and vaccine development.}, }
@article {pmid38832917, year = {2024}, author = {Eisenbraun, EL and Vulpis, TD and Prosser, BN and Horswill, AR and Blackwell, HE}, title = {Synthetic Peptides Capable of Potent Multigroup Staphylococcal Quorum Sensing Activation and Inhibition in Both Cultures and Biofilm Communities.}, journal = {Journal of the American Chemical Society}, volume = {146}, number = {23}, pages = {15941-15954}, pmid = {38832917}, issn = {1520-5126}, support = {R01 AI153185/AI/NIAID NIH HHS/United States ; S10 OD020022/OD/NIH HHS/United States ; S10 RR024601/RR/NCRR NIH HHS/United States ; T32 GM008349/GM/NIGMS NIH HHS/United States ; }, mesh = {*Quorum Sensing/drug effects ; *Biofilms/drug effects ; *Staphylococcus epidermidis/drug effects/physiology ; Peptides/pharmacology/chemistry/chemical synthesis ; Bacterial Proteins/metabolism/antagonists &amp; inhibitors ; Staphylococcus aureus/drug effects/physiology ; Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; }, abstract = {The pathogen Staphylococcus epidermidis uses a chemical signaling process, i.e., quorum sensing (QS), to form robust biofilms and cause human infection. Many questions remain about QS in S. epidermidis, as it uses this intercellular communication pathway to both negatively and positively regulate virulence traits. Herein, we report synthetic multigroup agonists and antagonists of the S. epidermidis accessory gene regulator (agr) QS system capable of potent superactivation and complete inhibition, respectively. These macrocyclic peptides maintain full efficacy across the three major agr specificity groups, and their activity can be "mode-switched" from agonist to antagonist via subtle residue-specific structural changes. We describe the design and synthesis of these non-native peptides and demonstrate that they can appreciably decrease biofilm formation on abiotic surfaces, underscoring the potential for agr agonism as a route to block S. epidermidis virulence. Additionally, we show that both the S. epidermidis agonists and antagonists are active in S. aureus, another common pathogen with a related agr system, yet only as antagonists. This result not only revealed one of the most potent agr inhibitors known in S. aureus but also highlighted differences in the mechanisms of agr agonism and antagonism between these related bacteria. Finally, our investigations reveal unexpected inhibitory behavior for certain S. epidermidis agr agonists at sub-activating concentrations, an observation that can be leveraged for the design of future probes with enhanced potencies. Together, these peptides provide a powerful tool set to interrogate the role of QS in S. epidermidis infections and in Staphylococcal pathogenicity in general.}, }
@article {pmid38832916, year = {2024}, author = {Zhou, J and Yang, L and Li, X and Dai, B and He, J and Wu, C and Pang, S and Xia, S and Rittmann, BE}, title = {Biogenic Palladium Improved Perchlorate Reduction during Nitrate Co-Reduction by Diverting Electron Flow in a Hydrogenotrophic Biofilm.}, journal = {Environmental science &amp; technology}, volume = {58}, number = {24}, pages = {10644-10651}, doi = {10.1021/acs.est.4c01496}, pmid = {38832916}, issn = {1520-5851}, mesh = {*Biofilms ; *Palladium/chemistry ; *Nitrates/metabolism ; *Perchlorates/metabolism ; Oxidation-Reduction ; Electrons ; Groundwater/chemistry ; }, abstract = {Microbial reduction of perchlorate (ClO4[-]) is emerging as a cost-effective strategy for groundwater remediation. However, the effectiveness of perchlorate reduction can be suppressed by the common co-contamination of nitrate (NO3[-]). We propose a means to overcome the limitation of ClO4[-] reduction: depositing palladium nanoparticles (Pd[0]NPs) within the matrix of a hydrogenotrophic biofilm. Two H2-based membrane biofilm reactors (MBfRs) were operated in parallel in long-term continuous and batch modes: one system had only a biofilm (bio-MBfR), while the other incorporated biogenic Pd[0]NPs in the biofilm matrix (bioPd-MBfR). For long-term co-reduction, bioPd-MBfR had a distinct advantage of oxyanion reduction fluxes, and it particularly alleviated the competitive advantage of NO3[-] reduction over ClO4[-] reduction. Batch tests also demonstrated that bioPd-MBfR gave more rapid reduction rates for ClO4[-] and ClO3[-] compared to those of bio-MBfR. Both biofilm communities were dominated by bacteria known to be perchlorate and nitrate reducers. Functional-gene abundances reflecting the intracellular electron flow from H2 to NADH to the reductases were supplanted by extracellular electron flow with the addition of Pd[0]NPs.}, }
@article {pmid38831973, year = {2024}, author = {Xu, Y and Wang, X and Gu, Y and Liang, C and Guo, W and Ngo, HH and Peng, L}, title = {Optimizing ciprofloxacin removal through regulations of trophic modes and FNA levels in a moving bed biofilm reactor performing sidestream partial nitritation.}, journal = {Water research X}, volume = {22}, number = {}, pages = {100216}, pmid = {38831973}, issn = {2589-9147}, abstract = {The performance of partial nitritation (PN)-moving bed biofilm reactor (MBBR) in removal of antibiotics in the sidestream wastewater has not been investigated so far. In this work, the removal of ciprofloxacin was assessed under varying free nitrous acid (FNA) levels and different trophic modes. For the first time, a positive correlation was observed between ciprofloxacin removal and FNA levels, either in the autotrophic PN-MBBR or in the mixotrophic PN-MBBR, mainly ascribed to the FNA-stimulating effect on heterotrophic bacteria (HB)-induced biodegradation. The maximum ciprofloxacin removal efficiency (∼98 %) and removal rate constant (0.021 L g[-1] SS h[-1]) were obtained in the mixotrophic PN-MBBR at an average FNA level of 0.056 mg-N L[-1], which were 5.8 and 51.2 times higher than the corresponding values in the autotrophic PN-MBBR at 0 mg FNA-N L[-1]. Increasing FNA from 0.006 to 0.056 mg-N L[-1] would inhibit ammonia oxidizing bacteria (AOB)-induced cometabolism and metabolism from 10.2 % and 6.9 % to 6.2 % and 6.4 %, respectively, while HB-induced cometabolism and metabolism increased from 31.2 % and 22.7 % to 41.9 % and 34.5 %, respectively. HB-induced cometabolism became the predominant biodegradation pathway (75.9 %-85.8 %) in the mixotrophic mode. Less antimicrobial biotransformation products without the piperazine or fluorine were newly identified to propose potential degradation pathways, corresponding to microbial-induced metabolic types and FNA levels. This work shed light on enhancing antibiotic removal via regulating both FNA accumulation and organic carbon addition in the PN-MBBR process treating sidestream wastewater.}, }
@article {pmid38831051, year = {2024}, author = {Shastry, RP and Bajire, SK and Banerjee, S and Shastry, KP and Hameed, A}, title = {Association Between Biofilm Formation and Extended-Spectrum Beta-Lactamase Production in Klebsiella pneumoniae Isolated from Fresh Fruits and Vegetables.}, journal = {Current microbiology}, volume = {81}, number = {7}, pages = {206}, pmid = {38831051}, issn = {1432-0991}, mesh = {*Biofilms/growth &amp; development ; *Klebsiella pneumoniae/genetics/drug effects/isolation &amp; purification ; *Vegetables/microbiology ; *beta-Lactamases/genetics/metabolism ; *Fruit/microbiology ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; }, abstract = {The presence of extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae in fresh fruits and vegetables is a growing public health concern. The primary objective of this study was to investigate the relationship between biofilm formation and extended-spectrum β-lactamase (ESBL) production in K. pneumoniae strains obtained from fresh fruits and vegetables. Out of 120 samples analysed, 94 samples (78%) were found to be positive for K. pneumoniae. Among the K. pneumoniae strains isolated, 74.5% were from vegetables, whereas the remaining (25.5%) were from fresh fruits. K. pneumoniae isolates were resistant to at least three different classes of antibiotics, with ceftazidime (90%) and cefotaxime (70%) showing the highest resistance rates. While the high occurrence of ESBL-producing and biofilm-forming K. pneumoniae strains were detected in vegetables (73.5% and 73.7%, respectively), considerable amounts of the same were also found in fresh fruits (26.5% and 26.3%, respectively). The results further showed a statistically significant (P < 0.001) association between biofilm formation and ESBL production in K. pneumoniae strains isolated from fresh fruits and vegetables. Furthermore, the majority (81%) of the ESBL-producing strains harbored the blaCTX-M gene, while a smaller proportion of strains carried the blaTEM gene (30%), blaSHV gene (11%) or blaOXA (8%). This study highlights the potential public health threat posed by K. pneumoniae in fresh fruits and vegetables and emphasizes the need for strict surveillance and control measures.}, }
@article {pmid38830542, year = {2024}, author = {Moshkanbaryans, L and Shah, V and Tan, LY and Jones, MP and Vickery, K and Alfa, M and Burdach, J}, title = {Comparison of two endoscope channel cleaning approaches to remove cyclic build-up biofilm.}, journal = {The Journal of hospital infection}, volume = {150}, number = {}, pages = {91-95}, doi = {10.1016/j.jhin.2024.05.014}, pmid = {38830542}, issn = {1532-2939}, mesh = {*Biofilms/growth &amp; development ; *Endoscopes/microbiology ; Disinfection/methods ; Decontamination/methods ; Humans ; Equipment Contamination/prevention &amp; control ; Bacteria/isolation &amp; purification ; }, abstract = {INTRODUCTION: Biofilm contributes significantly to bacterial persistence in endoscope channels. Enhanced cleaning methods capable of removing biofilm from all endoscope channels are required to decrease infection risk to patients. This head-to-head study compared cyclic build-up biofilm removal of an automated endoscope channel cleaner (AECC) with standard manual cleaning according to instructions for use (IFU) in polytetrafluorethylene channels.<br><br>METHODS: Cyclic build-up biofilm was grown in 1.4-mm (representing air/water and auxiliary channels) and 3.7-mm (representing suction/ biopsy channels) inner diameter polytetrafluorethylene channels. All channels were tested for residual total organic carbon, protein, and viable bacteria. Internationally recognized ISO 15883-5:2021 alert levels were used as cleaning benchmarks for protein (3 &#x3bc;g/cm[2]) and total organic carbon (6 &#x3bc;g/cm[2]).<br><br>RESULTS: The automated cleaner significantly outperformed manual cleaning for all markers assessed (protein, total organic carbon, viable bacteria) in 1.4-mm and 3.7-mm channels representing air/water/auxiliary and suction/biopsy channels, respectively. Manual cleaning failed to remove biofilm from the air/water and auxiliary channels. According to the IFU, these channels are not brushed, suggesting a potential root cause for a portion of the numerous endoscopy-associated infections reported in the literature.<br><br>CONCLUSION: AECC shows potential to deliver enhanced cleaning over current practice to all endoscope channels and may thereby address infection risk.}, }
@article {pmid38830531, year = {2024}, author = {Schlafer, S and Johnsen, KK and Kjærbølling, I and Schramm, A and Meyer, RL and Jørgensen, MR}, title = {The efficacy and safety of an enzyme-containing lozenge for dental biofilm control-a randomized controlled pilot trial.}, journal = {Journal of dentistry}, volume = {147}, number = {}, pages = {105107}, doi = {10.1016/j.jdent.2024.105107}, pmid = {38830531}, issn = {1879-176X}, mesh = {Humans ; *Dental Plaque/microbiology ; Female ; *Gingivitis/microbiology ; Male ; *Biofilms/drug effects ; Adult ; *Saliva/microbiology ; Pilot Projects ; *Dental Plaque Index ; *Periodontal Index ; Young Adult ; RNA, Ribosomal, 16S ; Microbiota/drug effects ; Double-Blind Method ; Oral Hygiene ; Treatment Outcome ; Hydrolases/therapeutic use ; Middle Aged ; }, abstract = {OBJECTIVES: To evaluate the effect of daily use of a multiple-enzyme lozenge on de novo plaque formation, on gingivitis development, and on the oral microbiome composition.<br><br>METHODS: This trial with two parallel arms included 24 healthy adults allocated to the Active (n = 12) or Placebo (n = 12) group. Subjects consumed one lozenge three times daily for seven days, and no oral hygiene procedures were allowed. Differences in de novo plaque accumulation between a baseline period, and one and seven days of intervention were assessed by the Turesky-modification of the Quigley-and-Hein-Plaque-Index (TM-QHPI). The development of gingivitis after seven days of intervention was assessed by the Gingival Index (GI). Plaque and saliva samples were collected at baseline and after seven days of intervention, and evaluated by 16S rRNA gene sequencing.<br><br>RESULTS: All subjects completed the study, and no adverse events were reported. After one day, the average TM-QHPI was significantly lower in the Active than in the Placebo group, as compared to baseline (p = 0.012). After 7 days, average TM-QHPI values did not differ significantly between groups (p = 0.37). GI values did not increase during the intervention period, with no difference between groups (p = 0.62). Bacterial richness increased in both plaque and saliva samples over a seven-day oral hygiene-free period, with a statistically significant difference for the saliva samples (p = 0.0495) between groups.<br><br>CONCLUSIONS: A multiple-enzymes lozenge decreased the build-up of de novo plaque after one day and slowed down the process of species increment in saliva. The lozenge may be an adjunct to regular mechanical plaque removal.<br><br>CLINICAL SIGNIFICANCE: Dental plaque is the main cause of caries, gingivitis, and periodontitis. The search for therapeutic adjuncts to mechanical plaque removal that have no harmful effects on the oral microbiome is important. Treatment with multiple plaque-matrix degrading enzymes is a promising non-biocidal approach to plaque control.}, }
@article {pmid38830110, year = {2024}, author = {}, title = {Correction for Postek et al., Substrate geometry affects population dynamics in a bacterial biofilm.}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, volume = {121}, number = {24}, pages = {e2408892121}, doi = {10.1073/pnas.2408892121}, pmid = {38830110}, issn = {1091-6490}, }
@article {pmid38829422, year = {2024}, author = {Jurado, V and Martin-Pozas, T and Fernandez-Cortes, A and Calaforra, JM and Sanchez-Moral, S and Saiz-Jimenez, C}, title = {Gypsum Cave Biofilm Communities are Strongly Influenced by Bat- And Arthropod-Related Fungi.}, journal = {Microbial ecology}, volume = {87}, number = {1}, pages = {80}, pmid = {38829422}, issn = {1432-184X}, mesh = {*Caves/microbiology ; *Chiroptera/microbiology/physiology ; Animals ; *Biofilms ; *Fungi/classification/physiology/genetics/isolation &amp; purification ; *Arthropods/microbiology ; *Calcium Sulfate ; Spain ; Biodiversity ; Mycobiome ; Soil Microbiology ; }, abstract = {The Gypsum Karst of Sorbas, Almeria, southeast Spain, includes a few caves whose entrances are open and allow the entry and roosting of numerous bats. Caves are characterized by their diversity of gypsum speleothems, such as stalactites, coralloids, gypsum crusts, etc. Colored biofilms can be observed on the walls of most caves, among which the Covadura and C3 caves were studied. The objective was to determine the influence that bat mycobiomes may have on the fungal communities of biofilms. The results indicate that the fungi retrieved from white and yellow biofilms in Covadura Cave (Ascomycota, Mortierellomycota, Basidiomycota) showed a wide diversity, depending on their location, and were highly influenced by the bat population, the guano and the arthropods that thrive in the guano, while C3 Cave was more strongly influenced by soil- and arthropod-related fungi (Ascomycota, Mortierellomycota), due to the absence of roosting bats.}, }
@article {pmid38828022, year = {2024}, author = {Kurnia, D and Padilah, R and Apriyanti, E and Dharsono, HDA}, title = {Phytochemical Analysis and Anti-Biofilm Potential That Cause Dental Caries from Black Cumin Seeds (Nigella sativa Linn.).}, journal = {Drug design, development and therapy}, volume = {18}, number = {}, pages = {1917-1932}, pmid = {38828022}, issn = {1177-8881}, mesh = {*Biofilms/drug effects ; *Nigella sativa/chemistry ; *Seeds/chemistry ; *Dental Caries/microbiology/drug therapy ; *Anti-Bacterial Agents/pharmacology/chemistry/isolation &amp; purification ; Humans ; *Phytochemicals/pharmacology/isolation &amp; purification/chemistry ; Plant Extracts/pharmacology/chemistry/isolation &amp; purification ; Microbial Sensitivity Tests ; Structure-Activity Relationship ; }, abstract = {The oral cavity is an excellent place for various microorganisms to grow. Spectrococcus mutans and Spectrococcus sanguinis are Gram-negative bacteria found in the oral cavity as pioneer biofilm formers on the tooth surface that cause caries. Caries treatment has been done with antibiotics and therapeutics, but the resistance level of S. mutans and S. sanguinis bacteria necessitates the exploration of new drug compounds. Black cumin (Nigella sativa Linn.) is known to contain secondary metabolites that have antioxidant, antibacterial, anti-biofilm, anti-inflammatory and antifungal activities. The purpose of this review article is to present data on the potential of Nigella sativa Linn seeds as anti-biofilm. This article will discuss biofilm-forming bacteria, the resistance mechanism of antibiotics, the bioactivity of N. sativa extracts and seed isolates together with the Structure Activity Relationship (SAR) review of N. sativa compound isolates. We collected data from reliable references that will illustrate the potential of N. sativa seeds as anti-biofilm drug.}, }
@article {pmid38826273, year = {2024}, author = {Nagy, K and Valappil, SK and Phan, TV and Li, S and Dér, L and Morris, R and Bos, J and Winslow, S and Galajda, P and Ràkhely, G and Austin, RH}, title = {Microfluidic Ecology Unravels the Genetic and Ecological Drivers of T4r Bacteriophage Resistance in E. coli: Insights into Biofilm-Mediated Evolution.}, journal = {Research square}, volume = {}, number = {}, pages = {}, pmid = {38826273}, issn = {2693-5015}, abstract = {We use a microfluidic ecology which generates non-uniform phage concentration gradients and micro-ecological niches to reveal the importance of time, spatial population structure and collective population dynamics in the de novo evolution of T4r bacteriophage resistant motile E. coli. An insensitive bacterial population against T4r phage occurs within 20 hours in small interconnected population niches created by a gradient of phage virions, driven by evolution in transient biofilm patches. Sequencing of the resistant bacteria reveals mutations at the receptor site of bacteriophage T4r as expected but also in genes associated with biofilm formation and surface adhesion, supporting the hypothesis that evolution within transient biofilms drives de novo phage resistance.}, }
@article {pmid38825455, year = {2024}, author = {Salazar-Sesatty, HA and Montoya-Hinojosa, EI and Villarreal-Salazar, V and Alvizo-Baez, CA and Camacho-Ortiz, A and Terrazas-Armendariz, LD and Luna-Cruz, IE and Alcocer-González, JM and Villarreal-Treviño, L and Flores-Treviño, S}, title = {Biofilm Eradication and Inhibition of Methicillin-Resistant Staphylococcus Clinical Isolates by Curcumin-Chitosan Magnetic Nanoparticles.}, journal = {Japanese journal of infectious diseases}, volume = {77}, number = {5}, pages = {260-268}, doi = {10.7883/yoken.JJID.2024.034}, pmid = {38825455}, issn = {1884-2836}, mesh = {*Biofilms/drug effects ; *Chitosan/pharmacology/chemistry ; *Curcumin/pharmacology ; *Anti-Bacterial Agents/pharmacology ; Humans ; *Methicillin-Resistant Staphylococcus aureus/drug effects ; *Microbial Sensitivity Tests ; *Staphylococcal Infections/microbiology/drug therapy ; Magnetite Nanoparticles/chemistry ; Oxacillin/pharmacology ; Staphylococcus/drug effects/physiology ; }, abstract = {Biofilm-producing methicillin-resistant Staphylococcus aureus (MRSA) and coagulase-negative staphylococci (MR-CoNS) pose clinical challenges in treating healthcare-associated infections. As alternative antimicrobial options are needed, in this study, we aimed to determine the effect of curcumin-chitosan magnetic nanoparticles (Cur-Chi-MNP) on the biofilms of staphylococcal clinical isolates. MRSA and CoNS clinical isolates were identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Antimicrobial susceptibility testing was performed using the broth microdilutions. Nanoparticles were synthesized by the co-precipitation of magnetic nanoparticles (MNP) and encapsulated by the ionotropic gelation of curcumin (Cur) and chitosan (Chi). Biofilm inhibition and eradication by nanoparticles, with and without the addition of oxacillin (OXA), were assessed in Staphylococcus strains. Cur-Chi-MNP showed antimicrobial activity against planktonic cells of MRSA and MR-CoNS strains and inhibited MRSA biofilm. The addition of OXA to Cur-Chi-MNP increased the biofilm inhibition and eradication activity against all staphylococcal strains (P = 0.0007), and higher biofilm activity was observed in the early biofilm stages. Cur-Chi-MNP showed antimicrobial and biofilm inhibitory activities against S. aureus. Addition of OXA increased biofilm inhibition and eradication activity against all staphylococcal strains. A combination treatment of Cur-Chi-MNP and OXA could potentially be used to treat staphylococcal biofilm-associated infections in the early stages before the establishment of biofilm bacterial cells.}, }
@article {pmid38824773, year = {2024}, author = {Shi, H and Mao, X and Yang, F and Zhu, M and Tan, N and Tan, W and Gu, T and Zhang, X}, title = {Multi-scale analysis of acidophilic microbial consortium biofilm's tolerance of lithium and cobalt ions in bioleaching.}, journal = {Journal of hazardous materials}, volume = {474}, number = {}, pages = {134764}, doi = {10.1016/j.jhazmat.2024.134764}, pmid = {38824773}, issn = {1873-3336}, mesh = {*Biofilms/drug effects ; *Cobalt/chemistry/toxicity ; *Lithium ; *Microbial Consortia/drug effects ; Iron/chemistry/metabolism ; Adsorption ; Sulfides/chemistry ; Electrodes ; Oxidation-Reduction ; }, abstract = {Metal ions stress will inhibit the oxidation capacity of iron and sulfur of an acidophilic microbial consortium (AMC), which leads to reduced bioleaching efficiency. This work explored the impacts of Li[+] and Co[2+] on the composition and function of AMC biofilms with a multi-scale approach. At the reactor scale, the results indicated that the oxidative activity, the adsorption capacity, and the biofilm formation ability of AMC on pyrite surfaces decreased under 500 mM Li[+] and 500 mM Co[2+]. At the biofilm scale, the electrochemical measurements showed that Li[+] and Co[2+] inhibited the charge transfer between the pyrite working electrode and the biofilm, and decreased the corrosion current density of the pyrite working electrode. At the cell scale, the content of proteins in extracellular polymers substrate (EPS) increased as the concentrations of metal ions increased. Moreover, the adsorption capacity of EPS for Li[+] and Co[2+] increased. At the microbial consortium scale, a BugBase phenotype analysis showed that under 500 mM Li[+] and 500 mM Co[2+], the antioxidant stress capacity and the content of mobile gene elements in AMC increased. The results in this work can provide useful data and theoretical support for the regulation strategy of the bioleaching of spent lithium-ion batteries to recover valuable metals.}, }
@article {pmid38822462, year = {2024}, author = {Khan, MAS and Islam, Z and Shah, ST and Rahman, SR}, title = {Characterization of biofilm formation and multi-drug resistance among Pseudomonas aeruginosa isolated from hospital wastewater in Dhaka, Bangladesh.}, journal = {Journal of water and health}, volume = {22}, number = {5}, pages = {825-834}, pmid = {38822462}, issn = {1477-8920}, support = {NA//University Grants Commission of Bangladesh/ ; }, mesh = {*Biofilms/drug effects ; *Pseudomonas aeruginosa/drug effects/physiology/isolation &amp; purification/genetics ; *Wastewater/microbiology ; Bangladesh/epidemiology ; *Drug Resistance, Multiple, Bacterial ; *Hospitals ; *Anti-Bacterial Agents/pharmacology ; Integrons ; Microbial Sensitivity Tests ; }, abstract = {Hospital wastewater has been identified as a hotspot for the emergence and transmission of multidrug-resistant (MDR) pathogens that present a serious threat to public health. Therefore, we investigated the current status of antibiotic resistance as well as the phenotypic and genotypic basis of biofilm formation in Pseudomonas aeruginosa from hospital wastewater in Dhaka, Bangladesh. The disc diffusion method and the crystal violet assay were performed to characterize antimicrobial resistance and biofilm formation, respectively. Biofilm and integron-associated genes were amplified by the polymerase chain reaction. Isolates exhibited varying degrees of resistance to different antibiotics, in which >80% of isolates showed sensitivity to meropenem, amikacin, and gentamicin. The results indicated that 93.82% of isolates were MDR and 71 out of 76 MDR isolates showed biofilm formation activities. We observed the high prevalence of biofilm-related genes, in which algD[+]pelF[+]pslD[+] (82.7%) was found to be the prevalent biofilm genotypic pattern. Sixteen isolates (19.75%) possessed class 1 integron (int1) genes. However, statistical analysis revealed no significant association between biofilm formation and multidrug resistance (χ[2] = 0.35, P = 0.55). Taken together, hospital wastewater in Dhaka city may act as a reservoir for MDR and biofilm-forming P. aeruginosa, and therefore, the adequate treatment of wastewater is recommended to reduce the occurrence of outbreaks.}, }
@article {pmid38821810, year = {2024}, author = {Khan, ZA and Wani, MY and Ahmad, A and Basha, MT and Aly, NA and Yakout, AA}, title = {Multifunctional chitosan-cross linked- curcumin-tannic acid biocomposites disrupt quorum sensing and biofilm formation in pathogenic bacteria.}, journal = {International journal of biological macromolecules}, volume = {271}, number = {Pt 1}, pages = {132719}, doi = {10.1016/j.ijbiomac.2024.132719}, pmid = {38821810}, issn = {1879-0003}, mesh = {*Chitosan/chemistry/pharmacology ; *Quorum Sensing/drug effects ; *Biofilms/drug effects/growth &amp; development ; *Curcumin/pharmacology/chemistry ; *Tannins/chemistry/pharmacology ; *Pseudomonas aeruginosa/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; Chromobacterium/drug effects ; Microbial Sensitivity Tests ; Polyphenols ; }, abstract = {Natural products have a long history of success in treating bacterial infections, making them a promising source for novel antibacterial medications. Curcumin, an essential component of turmeric, has shown potential in treating bacterial infections and in this study, we covalently immobilized curcumin (Cur) onto chitosan (CS) using glutaraldehyde and tannic acid (TA), resulting in the fabrication of novel biocomposites with varying CS/Cur/TA ratios. Comprehensive characterization of these ternary biocomposites was conducted using FTIR, SEM, XPS, and XRD to assess their morphology, functional groups, and chemical structures. The inhibitory efficacy of these novel biocomposites (n = 4) against the growth and viability of Pseudomonas aeruginosa (ATCC27853) and Chromobacterium violaceum (ATCC12472) was evaluated and the most promising composite (C3) was investigated for its impact on quorum sensing (QS) and biofilm formation in these bacteria. Remarkably, this biocomposite significantly disrupted QS circuits and effectively curtailed biofilm formation in the tested pathogens without inducing appreciable toxicity. These findings underscore its potential for future in vivo studies, positioning it as a promising candidate for the development of biofilm disrupting antibacterial agents.}, }
@article {pmid38821282, year = {2024}, author = {Yu, C and Liu, Y and Zhang, Y and Shen, MZ and Wang, JH and Chi, ZY}, title = {Seawater Chlorella sp. biofilm for mariculture effluent polishing under environmental combined antibiotics exposure and ecological risk evaluation based on parent antibiotics and transformation products.}, journal = {The Science of the total environment}, volume = {939}, number = {}, pages = {173643}, doi = {10.1016/j.scitotenv.2024.173643}, pmid = {38821282}, issn = {1879-1026}, mesh = {*Chlorella/physiology/drug effects ; *Biofilms/drug effects ; *Anti-Bacterial Agents/toxicity ; *Water Pollutants, Chemical/toxicity ; *Seawater/chemistry ; Risk Assessment ; Waste Disposal, Fluid/methods ; Aquaculture ; Microalgae/drug effects/physiology ; }, abstract = {Mariculture effluent polishing with microalgal biofilm could realize effective nutrients removal and resolve the microalgae-water separation issue via biofilm scraping or in-situ aquatic animal grazing. Ubiquitous existence of antibiotics in mariculture effluents may affect the remediation performances and arouse ecological risks. The influence of combined antibiotics exposure at environment-relevant concentrations towards attached microalgae suitable for mariculture effluent polishing is currently lack of research. Results from suspended cultures could offer limited guidance since biofilms are richer in extracellular polymeric substances that may protect the cells from antibiotics and alter their transformation pathways. This study, therefore, explored the effects of combined antibiotics exposure at environmental concentrations towards seawater Chlorella sp. biofilm in terms of microalgal growth characteristics, nutrients removal, anti-oxidative responses, and antibiotics removal and transformations. Sulfamethoxazole (SMX), tetracycline (TL), and clarithromycin (CLA) in single, binary, and triple combinations were investigated. SMX + TL displayed toxicity synergism while TL + CLA revealed toxicity antagonism. Phosphorus removal was comparable under all conditions, while nitrogen removal was significantly higher under SMX and TL + CLA exposure. Anti-oxidative responses suggested microalgal acclimation towards SMX, while toxicity antagonism between TL and CLA generated least cellular oxidative damage. Parent antibiotics removal was in the order of TL (74.5-85.2 %) > CLA (60.8-69.5 %) > SMX (13.5-44.1 %), with higher removal efficiencies observed under combined than single antibiotic exposure. Considering the impact of residual parent antibiotics, CLA involved cultures were identified of high ecological risks, while medium risks were indicated in other cultures. Transformation products (TPs) of SMX and CLA displayed negligible aquatic toxicity, the parent antibiotics themselves deserve advanced removal. Four out of eight TPs of TL could generate chronic toxicity, and the elimination of these TPs should be prioritized for TL involved cultures. This study expands the knowledge of combined antibiotics exposure upon microalgal biofilm based mariculture effluent polishing.}, }
@article {pmid38820569, year = {2024}, author = {Rapsinski, GJ and Michaels, LA and Hill, M and Yarrington, KD and Haas, AL and D'Amico, EJ and Armbruster, CR and Zemke, A and Limoli, D and Bomberger, JM}, title = {Pseudomonas aeruginosa senses and responds to epithelial potassium flux via Kdp operon to promote biofilm.}, journal = {PLoS pathogens}, volume = {20}, number = {5}, pages = {e1011453}, pmid = {38820569}, issn = {1553-7374}, support = {T32 AI007519/AI/NIAID NIH HHS/United States ; R01 HL142587/HL/NHLBI NIH HHS/United States ; R33 HL137077/HL/NHLBI NIH HHS/United States ; K12 HD052892/HD/NICHD NIH HHS/United States ; K12 HD000850/HD/NICHD NIH HHS/United States ; }, mesh = {*Biofilms/growth &amp; development ; *Pseudomonas aeruginosa/genetics/metabolism/physiology ; Humans ; *Cystic Fibrosis/microbiology/metabolism ; *Epithelial Cells/microbiology/metabolism ; *Operon ; *Potassium/metabolism ; *Pseudomonas Infections/microbiology/metabolism ; Bacterial Proteins/metabolism/genetics ; Respiratory Mucosa/metabolism/microbiology ; }, abstract = {Mucosa-associated biofilms are associated with many human disease states, but the host mechanisms promoting biofilm remain unclear. In chronic respiratory diseases like cystic fibrosis (CF), Pseudomonas aeruginosa establishes chronic infection through biofilm formation. P. aeruginosa can be attracted to interspecies biofilms through potassium currents emanating from the biofilms. We hypothesized that P. aeruginosa could, similarly, sense and respond to the potassium efflux from human airway epithelial cells (AECs) to promote biofilm. Using respiratory epithelial co-culture biofilm imaging assays of P. aeruginosa grown in association with CF bronchial epithelial cells (CFBE41o-), we found that P. aeruginosa biofilm was increased by potassium efflux from AECs, as examined by potentiating large conductance potassium channel, BKCa (NS19504) potassium efflux. This phenotype is driven by increased bacterial attachment and increased coalescence of bacteria into aggregates. Conversely, biofilm formation was reduced when AECs were treated with a BKCa blocker (paxilline). Using an agar-based macroscopic chemotaxis assay, we determined that P. aeruginosa chemotaxes toward potassium and screened transposon mutants to discover that disruption of the high-sensitivity potassium transporter, KdpFABC, and the two-component potassium sensing system, KdpDE, reduces P. aeruginosa potassium chemotaxis. In respiratory epithelial co-culture biofilm imaging assays, a KdpFABCDE deficient P. aeruginosa strain demonstrated reduced biofilm growth in association with AECs while maintaining biofilm formation on abiotic surfaces. Furthermore, we determined that the Kdp operon is expressed in vivo in people with CF and the genes are conserved in CF isolates. Collectively, these data suggest that P. aeruginosa biofilm formation can be increased by attracting bacteria to the mucosal surface and enhancing coalescence into microcolonies through aberrant AEC potassium efflux sensed by the KdpFABCDE system. These findings suggest host electrochemical signaling can enhance biofilm, a novel host-pathogen interaction, and potassium flux could be a therapeutic target to prevent chronic infections in diseases with mucosa-associated biofilms, like CF.}, }
@article {pmid38820308, year = {2024}, author = {He, X and Su, D and Bai, X and Yuan, C}, title = {Chemically Modulating Ceria-Based Artificial Haloperoxidase for Enhanced Antibacterial Activity and Biofilm Inhibition.}, journal = {ACS applied materials &amp; interfaces}, volume = {16}, number = {23}, pages = {30117-30127}, doi = {10.1021/acsami.4c05025}, pmid = {38820308}, issn = {1944-8252}, mesh = {*Anti-Bacterial Agents/pharmacology/chemistry ; *Biofilms/drug effects ; Biofouling/prevention &amp; control ; *Cerium/chemistry/pharmacology ; Dihydroxyphenylalanine/chemistry/pharmacology ; Escherichia coli/drug effects ; Microbial Sensitivity Tests ; Nanocomposites/chemistry ; *Peroxidases/metabolism/chemistry ; Quorum Sensing/drug effects ; Staphylococcus aureus/drug effects ; }, abstract = {Ceria (CeO2) nanoparticles with haloperoxidase (HPO)-like activity have gained attention as a biologically benign antifoulant. 3,4-Dihydroxy-l-phenylalanine (DOPA), a main composition in mussel foot proteins, plays a crucial role in the biofouling process. However, the impact on the HPO-like activity and antifouling performance of CeO2 nanoparticles when DOPA molecules adsorb on them remains unexplored. This interesting question warrants investigation, particularly considering that it may occur in an actual marine environment. Herein, the interaction between DOPA and CeO2 is explored. Despite the higher Ce[3+] fractions and the lower band gap energies due to the electron transfer from DOPA to the CeO2 surface, DOPA still had a slightly negative effect on the HPO-like activity of CeO2 since they decreased the exposed Ce[3+] sites. The DOPA-CeO2 nanocomposites with HPO-like activities could kill bacteria and trigger quorum-sensing signaling quenching, achieving a biofilm inhibition performance. Amazingly, 0.1% DOPA-CeO2 nanocomposite exhibited higher antibacterial activity and better biofilm suppression activities due to its HPO-like activity and positive zeta potential. The remarkable results demonstrated that DOPA, as a participant in the biofouling process, could enhance the antibacterial activity and antifouling performance of CeO2 nanoparticles at an appropriate concentration.}, }
@article {pmid38819774, year = {2024}, author = {de Souto Sobrinho, JD and de Valença Silva, AK and de Medeiros, KB and Silva, MLCR and de Medeiros, ABM and de Sousa, DLC and de Azevedo, SS and de Sousa Américo Batista Santos, C}, title = {Antimicrobial resistance, enterotoxin and biofilm production genes in Staphylococcus spp. isolated from facilities and fomites in veterinary hospital in the Caatinga biome.}, journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]}, volume = {55}, number = {3}, pages = {2885-2892}, pmid = {38819774}, issn = {1678-4405}, mesh = {*Biofilms/growth &amp; development/drug effects ; *Staphylococcus/genetics/drug effects/isolation &amp; purification/physiology ; Animals ; *Enterotoxins/genetics ; *Anti-Bacterial Agents/pharmacology ; Brazil ; *Hospitals, Animal ; *Fomites/microbiology ; *Microbial Sensitivity Tests ; Cats ; Dogs ; Drug Resistance, Bacterial/genetics ; Staphylococcal Infections/microbiology/veterinary ; Bacterial Proteins/genetics/metabolism ; }, abstract = {The Caatinga biome occurs only in Brazil and offers epidemiological conditions that should be assessed differently from other regions of Brazil and the world. Thus, the aim of this survey was to identify antimicrobial resistance, enterotoxin and biofilm production genes in Staphylococcus spp. isolated from facilities and fomites in a veterinary hospital in Caatinga biome. Samples were collected from surfaces of small animal clinical care tables (n =8), cages in the dog and cat hospitalisation sector and animals with infectious diseases (n = 21), small animal surgical centre (n =8), sterilisation sector (n =7) and stethoscopes (n = 32) by using sterile swabs. Bacterial isolation and identification, antimicrobial resistance phenotypic test and molecular detection of antimicrobial resistance, biofilm formation and enterotoxin genes were carried out. Ninety-five bacterial isolates were obtained, and 29 (30.5%) were identified as Staphylococcus spp. Overall, 13 isolates (44.8%) of six species of Staphylococcus spp. showed antimicrobial resistance profile, as well as S. haemolyticus expressed phenotypic profile of multidrug resistance. The antimicrobials with the highest resistance rates were penicillin and tetracycline. The most frequent resistance genes were blaZ and tetM, both detected in 10 (76.9%) isolates. The mecA, tetL and tetK genes had frequencies of 38.5% (5/13), 23.1% (3/13) and 15.4% (2/13), respectively. The biofilm production marker, icaD gene, was detected in one S. sciuri strain. SEE gene, which encodes enterotoxins, was detected in 15.4% (2/13) of the strains (S. pseudintermedius and S. intermedius). The occurrence of Staphylococcus spp. carrying resistance genes to diferent classes of antimicrobials, presenting MDR phenotypic pattern and carrying enterotoxins and biofim encoding genes recovered from veterinary hospital facilities and fomites in the Caatinga biome reinforce the need to implement prevention cares in veterinary practices to avoid One Health-concerning conditions.}, }
@article {pmid38817812, year = {2023}, author = {Zhang, Y and Bhasme, P and Reddy, DS and Liu, D and Yu, Z and Zhao, T and Zheng, Y and Kumar, A and Yu, H and Ma, LZ}, title = {Dual functions: A coumarin-chalcone conjugate inhibits cyclic-di-GMP and quorum-sensing signaling to reduce biofilm formation and virulence of pathogens.}, journal = {mLife}, volume = {2}, number = {3}, pages = {283-294}, pmid = {38817812}, issn = {2770-100X}, abstract = {Antibiotic resistance or tolerance of pathogens is one of the most serious global public health threats. Bacteria in biofilms show extreme tolerance to almost all antibiotic classes. Thus, use of antibiofilm drugs without bacterial-killing effects is one of the strategies to combat antibiotic tolerance. In this study, we discovered a coumarin-chalcone conjugate C9, which can inhibit the biofilm formation of three common pathogens that cause nosocomial infections, namely, Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli, with the best antibiofilm activity against P. aeruginosa. Further investigations indicate that C9 decreases the synthesis of the key biofilm matrix exopolysaccharide Psl and bacterial second messenger cyclic-di-GMP. Meanwhile, C9 can interfere with the regulation of the quorum sensing (QS) system to reduce the virulence of P. aeruginosa. C9 treatment enhances the sensitivity of biofilm to several antibiotics and reduces the survival rate of P. aeruginosa under starvation or oxidative stress conditions, indicating its excellent potential for use as an antibiofilm-forming and anti-QS drug.}, }
@article {pmid38815887, year = {2024}, author = {Chen, X and Chen, CE and Cheng, S and Sweetman, AJ}, title = {Bisphenol A sorption on commercial polyvinyl chloride microplastics: Effects of UV-aging, biofilm colonization and additives on plastic behaviour in the environment.}, journal = {Environmental pollution (Barking, Essex : 1987)}, volume = {356}, number = {}, pages = {124218}, doi = {10.1016/j.envpol.2024.124218}, pmid = {38815887}, issn = {1873-6424}, mesh = {*Polyvinyl Chloride/chemistry ; *Benzhydryl Compounds/chemistry ; *Phenols/chemistry ; *Biofilms ; Adsorption ; *Microplastics/chemistry ; *Ultraviolet Rays ; *Water Pollutants, Chemical/chemistry ; Plastics/chemistry ; }, abstract = {Chemical additives are important components in commercial microplastics and their leaching behaviour has been widely studied. However, little is known about the potential effect of additives on the adsorption/desorption behaviour of pollutants on microplastics and their subsequent role as vectors for pollutant transport in the environment. In this study, two types of commercial polyvinyl chloride (PVC1 and PVC2) microplastics were aged by UV irradiation and biotic modification via biofilm colonization to investigate the adsorption and desorption behaviour of bisphenol A (BPA). Surface cracks and new functional groups (e.g., O-H) were found on PVC1 after UV irradiation, which increased available adsorption sites and enhanced H‒bonding interaction, resulting in an adsorption capacity increase from 1.28 μg/L to 1.85 μg/L. However, the adsorption and desorption capacity not showed significant changes for PVC2, which might be related to the few characteristic changes after UV aging with the protection of light stabilizers and antioxidants. The adsorption capacity ranged from 1.28 μg/L to 2.06 μg/L for PVC1 and PVC2 microplastics, and increased to 1.62 μg/L-2.95 μg/L after colonization by biofilms. The increased adsorption ability might be related to the N-H functional group, amide groups generated by microorganisms enhancing the affinity for BPA. The opposite effect was observed for desorption. Plasticizers can be metabolized during biofilm formation processes and might play an important role in microorganism colonization. In addition, antioxidants and UV stabilizers might also indirectly influence the colonization of microorganisms' on microplastics by controlling the degree to which PVC microplastics age under UV. The amount of biomass loading on the microplastics would further alter the adsorption/desorption behaviour of contaminants. This study provides important new insights into the evaluation of the fate of plastic particles in natural environments.}, }
@article {pmid38814458, year = {2024}, author = {Kyei, L and Piedl, K and Menegatti, C and Miller, EM and Mevers, E}, title = {Discovery of Biofilm Inhibitors from the Microbiota of Marine Egg Masses.}, journal = {Journal of natural products}, volume = {87}, number = {6}, pages = {1635-1642}, pmid = {38814458}, issn = {1520-6025}, support = {R35 GM146740/GM/NIGMS NIH HHS/United States ; }, mesh = {*Biofilms/drug effects ; *Staphylococcus aureus/drug effects ; Animals ; *Pseudomonas aeruginosa/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; Molecular Structure ; Microbiota/drug effects ; Microbial Sensitivity Tests ; Snails/microbiology ; Siderophores/pharmacology/chemistry ; Marine Biology ; Biological Products/pharmacology/chemistry ; }, abstract = {Biofilms commonly develop in immunocompromised patients, which leads to persistent infections that are difficult to treat. In the biofilm state, bacteria are protected against both antibiotics and the host's immune system; currently, there are no therapeutics that target biofilms. In this study, we screened a chemical fraction library representing the natural product capacity of the microbiota of marine egg masses, namely, the moon snail egg collars. This led to the identification of active fractions targeting both Pseudomonas aeruginosa and Staphylococcus aureus biofilms. Subsequent analysis revealed that a subset of these fractions were capable of eradicating preformed biofilms, all against S. aureus. Bioassay-guided isolation led us to identify pseudochelin A, a known siderophore, as a S. aureus biofilm inhibitor with an IC50 of 88.5 μM. Mass spectrometry-based metabolomic analyses revealed widespread production of pseudochelin A among fractions possessing S. aureus antibiofilm properties. In addition, a key biosynthetic gene involved in producing pseudochelin A was detected on 30% of the moon snail egg collars and pseudochelin A is capable of inhibiting the formation of biofilms (IC50 50.6 μM) produced by ecologically relevant bacterial strains. We propose that pseudochelin A may have a role in shaping the microbiome or protecting the egg collars from microbiofouling.}, }
@article {pmid38813959, year = {2024}, author = {Fattouh, N and Husni, R and Finianos, M and Bitar, I and Khalaf, RA}, title = {Adhesive and biofilm-forming Candida glabrata Lebanese hospital isolates harbour mutations in subtelomeric silencers and adhesins.}, journal = {Mycoses}, volume = {67}, number = {6}, pages = {e13750}, doi = {10.1111/myc.13750}, pmid = {38813959}, issn = {1439-0507}, mesh = {*Biofilms/growth &amp; development ; *Candida glabrata/genetics/drug effects/isolation &amp; purification/pathogenicity/physiology ; Lebanon ; Animals ; Mice ; *Drug Resistance, Fungal/genetics ; *Antifungal Agents/pharmacology ; Humans ; Virulence/genetics ; *Candidiasis/microbiology ; *Mutation ; Fungal Proteins/genetics ; Polymorphism, Single Nucleotide ; Disease Models, Animal ; Azoles/pharmacology ; Microbial Sensitivity Tests ; Hospitals ; Female ; }, abstract = {BACKGROUND: The prevalence of Candida glabrata healthcare-associated infections is on the rise worldwide and in Lebanon, Candida glabrata infections are difficult to treat as a result of their resistance to azole antifungals and their ability to form biofilms.<br><br>OBJECTIVES: The first objective of this study was to quantify biofilm biomass in the most virulent C.&#x2009;glabrata isolates detected in a Lebanese hospital. In addition, other pathogenicity attributes were evaluated. The second objective was to identify the mechanisms of azole resistance in those isolates.<br><br>METHODS: A mouse model of disseminated systemic infection was developed to evaluate the degree of virulence of 41 azole-resistant C.&#x2009;glabrata collected from a Lebanese hospital. The most virulent isolates were further evaluated alongside an isolate having attenuated virulence and a reference strain for comparative purposes. A DNA-sequencing approach was adopted to detect single nucleotide polymorphisms (SNPs) leading to amino acid changes in proteins involved in azole resistance and biofilm formation. This genomic approach was supported by several phenotypic assays.<br><br>RESULTS: All chosen virulent isolates exhibited increased adhesion and biofilm biomass compared to the isolate having attenuated virulence. The amino acid substitutions D679E and I739N detected in the subtelomeric silencer Sir3 are potentially involved- in increased adhesion. In all isolates, amino acid substitutions were detected in the ATP-binding cassette transporters Cdr1 and Pdh1 and their transcriptional regulator Pdr1.<br><br>CONCLUSIONS: In summary, increased adhesion led to stable biofilm formation since mutated Sir3 could de-repress adhesins, while decreased azole susceptibility could result from mutations in Cdr1, Pdh1 and Pdr1.}, }
@article {pmid38812547, year = {2024}, author = {Guo, T and Zhou, N and Yang, L and Wang, Z and Huan, C and Lin, T and Bao, G and Hu, J and Li, G}, title = {Acinetobacter baumannii biofilm was inhibited by tryptanthrin through disrupting its different stages and genes expression.}, journal = {iScience}, volume = {27}, number = {6}, pages = {109942}, pmid = {38812547}, issn = {2589-0042}, abstract = {Biofilm formation plays a significant role in antibiotic resistance, necessitating the search for alternative therapies against biofilm-associated infections. This study demonstrates that 20 μg/mL tryptanthrin can hinder biofilm formation above 50% in various A. baumannii strains. Tryptanthrin impacts various stages of biofilm formation, including the inhibition of surface motility and eDNA release in A. baumannii, as well as an increase in its sensitivity to H202. RT-qPCR analysis reveals that tryptanthrin significantly decreases the expression of the following genes: abaI (19.07%), abaR (33.47%), bfmR (43.41%), csuA/B (64.16%), csuE (50.20%), ompA (67.93%), and katE (72.53%), which are related to biofilm formation and quorum sensing. Furthermore, tryptanthrin is relatively safe and can reduce the virulence of A. baumannii in a Galleria mellonella infection model. Overall, our study demonstrates the potential of tryptanthrin in controlling biofilm formation and virulence of A. baumannii by disrupting different stages of biofilm formation and intercellular signaling communication.}, }
@article {pmid38812355, year = {2024}, author = {Liu, Y and Li, K and Zhuang, W and Liang, L and Chen, X and Yu, D}, title = {Tetrahedral framework nucleic acid-based small-molecule inhibitor delivery for ecological prevention of biofilm.}, journal = {Cell proliferation}, volume = {57}, number = {9}, pages = {e13678}, pmid = {38812355}, issn = {1365-2184}, support = {82373255//National Natural Science Foundation of China/ ; 20240504//College Students' Innovative Entrepreneurial Training Plan Program/ ; 20240516//College Students' Innovative Entrepreneurial Training Plan Program/ ; 2022TQ0381//China Postdoctoral Science Foundation/ ; 2023M744045//China Postdoctoral Science Foundation/ ; }, mesh = {*Biofilms/drug effects ; *Streptococcus mutans/drug effects ; *Nucleic Acids/pharmacology ; *Dental Caries/prevention &amp; control/microbiology ; Animals ; Anti-Bacterial Agents/pharmacology/chemistry ; Glucosyltransferases/antagonists &amp; inhibitors/metabolism ; Humans ; Drug Delivery Systems/methods ; }, abstract = {Biofilm formation constitutes the primary cause of various chronic infections, such as wound infections, gastrointestinal inflammation and dental caries. While preliminary achievement of biofilm inhibition is possible, the challenge lies in the difficulty of eliminating the bactericidal effects of current drugs that lead to microbiota imbalance. This study, utilizing in vitro and in vivo models of dental caries, aims to efficiently inhibit biofilm formation without inducing bactericidal effects, even against pathogenic bacteria. The tetrahedral framework nucleic acid (tFNA) was employed as a delivery vector for a small-molecule inhibitor (smI) specifically targeting the activity of glucosyltransferases C (GtfC). It was observed that tFNA loaded smI in a small-groove binding manner, efficiently transferring it into Streptococcus mutans, thereby inhibiting GtfC activity and extracellular polymeric substances formation without compromising bacterial survival. Furthermore, smI-loaded tFNA demonstrated a reduction in the severity of dental caries in vivo without adversely affecting oral microbial diversity and exhibited desirable topical and systemic biosafety. This study emphasizes the concept of 'ecological prevention of biofilm', which is anticipated to advance the optimization of biofilm prevention strategies and the clinical application of DNA nanocarrier-based drug formulations.}, }
@article {pmid38810833, year = {2024}, author = {Karaduran, B and Çelik, S and Üçüncü, MY and Topçuoğlu, N and Gök, MK and Koruyucu, M}, title = {Antibacterial effects of silver diamine fluoride, potassium iodide and nanosilver fluoride on dual-species biofilm.}, journal = {Journal of dentistry}, volume = {147}, number = {}, pages = {105097}, doi = {10.1016/j.jdent.2024.105097}, pmid = {38810833}, issn = {1879-176X}, mesh = {*Silver Compounds/pharmacology ; *Biofilms/drug effects ; *Potassium Iodide/pharmacology ; *Quaternary Ammonium Compounds/pharmacology ; *Anti-Bacterial Agents/pharmacology ; *Streptococcus mutans/drug effects ; *Fluorides, Topical/pharmacology ; Humans ; *Lacticaseibacillus casei/drug effects ; Sodium Hypochlorite/pharmacology ; Chlorhexidine/pharmacology ; Dental Enamel/drug effects ; Microscopy, Electron, Scanning ; Microscopy, Confocal ; Materials Testing ; Fluorides/pharmacology ; Metal Nanoparticles ; }, abstract = {OBJECTIVES: This study aims to evaluate antibacterial effects of silver diamine fluoride (SDF), SDF/potassium iodide (KI), and nanosilver fluoride (NSF).<br><br>METHODS: Antimicrobial activity of sterile saline, 5% sodium hypochlorite (NaOCl), 2% chlorhexidine (CHX), SDF, SDF/KI, NSF, and KI solutions against Streptococcus mutans and Lactobacillus casei was assessed through disc diffusion tests. A dual-species biofilm of S. mutans-L. casei was formed on 48 enamel samples, divided into six groups (n = 8). Group 1 was treated with sterile saline, Group 2 with 5% NaOCl, Group 3 with 2% CHX, Group 4 with SDF, Group 5 with SDF/KI, and Group 6 with NSF. The samples were analysed using confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Statistical analysis utilized Shapiro-Wilk and Kruskal-Wallis tests and multiple comparisons were conducted using Dunn test.<br><br>RESULTS: SDF, SDF/KI, and NaOCl displayed significantly higher antibacterial activity against dual-species biofilm compared to NSF and CHX (p < 0.050).<br><br>CONCLUSIONS: In conclusion, SDF and SDF/KI demonstrated greater antibacterial activity than NSF. SDF's antibacterial activity was unaffected by KI. Further research is needed to determine the appropriate content and concentration for achieving effective antibacterial activity with NSF.<br><br>CLINICAL SIGNIFICANCE: The use of silver-containing materials is increasing in popularity within pediatric dentistry. In this study, an endeavor has been made to assist pediatric dentists in determining which solution might be more advantageous for preventing caries.}, }
@article {pmid38810821, year = {2024}, author = {Wang, J and Zhang, B and Huang, Y and Zhu, X and Xia, A and Zhu, X and Liao, Q}, title = {Temperature-controlled microalgal biofilm detachment and harvesting assisted by ultrasonic from 3D porous substrates grafted with thermosensitive gels.}, journal = {Environmental research}, volume = {256}, number = {}, pages = {119245}, doi = {10.1016/j.envres.2024.119245}, pmid = {38810821}, issn = {1096-0953}, mesh = {*Biofilms/growth &amp; development ; *Microalgae/growth &amp; development ; *Temperature ; Porosity ; *Gels/chemistry ; Acrylamides/chemistry ; }, abstract = {Microalgae have been renowned as the most promising energy organism with significant potential in carbon fixation. In the large-scale cultivation of microalgae, the 3D porous substrate with higher specific surface area is favorable to microalgae adsorption and biofilm formation, whereas difficult for biofilm detachment and microalgae harvesting. To solve this contradiction, N-isopropylacrylamide, a temperature-responsive gels material, was grafted onto the inner surface of the 3D porous substrate to form temperature-controllable interface wettability. The interfacial free energy between microalgae biofilm and the substrates increased from -63.02 mJ/m[2] to -31.89 mJ/m[2] when temperature was lowered from 32 °C to 17 °C, weakening the adsorption capacity of cells to the surface, and making the biofilm detachment ratio increased to 50.8%. When further cooling the environmental temperature to 4 °C, the detachment capability of microalgae biofilm kept growing. 91.6% of the cells in the biofilm were harvesting from the 3D porous substrate. And the biofilm detached rate was up to 19.84 g/m[2]/h, realizing the temperature-controlled microalgae biofilm harvesting. But, microalgae growth results in the secretion of extracellular polymeric substances (EPS), which enhanced biofilm adhesion and made cell detachment more difficult. Thus, ultrasonic vibration was used to reinforce biofilm detachment. With the help of ultrasonic vibration, microalgae biofilm detached rate increased by 143.45% to 41.07 g/m[2]/h. These findings provide a solid foundation for further development of microalgae biofilm detachment and harvesting technology.}, }
@article {pmid38810811, year = {2024}, author = {Zhang, W and Liang, W and Jin, J and Meng, S and He, Z and Ali, M and Saikaly, PE}, title = {Filtration performance of biofilm membrane bioreactor: Fouling control by threshold flux operation.}, journal = {Chemosphere}, volume = {362}, number = {}, pages = {142458}, doi = {10.1016/j.chemosphere.2024.142458}, pmid = {38810811}, issn = {1879-1298}, mesh = {*Bioreactors/microbiology ; *Biofilms/growth &amp; development ; *Filtration/methods ; *Membranes, Artificial ; *Waste Disposal, Fluid/methods ; Sewage/microbiology ; Biofouling/prevention &amp; control ; }, abstract = {Membrane fouling is the major factor that restricts the furtherly widespread use of membrane bioreactor (MBR). As a new generation of MBR, biofilm membrane bioreactor (BF-MBR) demonstrates high treatment efficiency and low sludge growth rate, however the filtration performance improvement and membrane fouling control are still the challenges for its further development. This work investigated the filtration performance using resistance in series model and membrane fouling control via threshold flux for BF-MBR. At first, the flux behavior and filtration resistance under various operating conditions, including agitation speed, membrane and TMP, were explored by resistance in series model. Because of the desirable anti-fouling capacity, UP100 and UP030 had the high threshold flux (100 and 90 L m[-2] h[-1]) and low irreversible fouling resistance (1 and 1.3 × 10[-10] m[-1]). Higher shear stress produced by higher agitation speed could reduce membrane fouling, while greatly promote the threshold flux (138 L m[-2] h[-1]) and membrane cleaning efficiency (96%). Moreover, increasing shear stress or selecting membrane with large pore size could decrease the fouling rate and raise the threshold flux. As for TMP, high TMP reduced the removal rate for organic and nutrient, and enhanced the irreversible fouling. Besides, the aerobic-BF-MBR (101 L m[-2] h[-1] and 1.3 × 10[-10] m[-1]) with lower foulant concentration had a better filtration performance than anoxic-BF-MBR (90 L m[-2] h[-1] and 1.5 × 10[-10] m[-1]). Additionally, the long-term tests with 10 cycles were conducted to evaluate the industrial application value of BF-MBR (45-58 L m[-2] h[-1]). This work provides the technical support for sustainable filtration performance of BF-MBR.}, }
@article {pmid38809833, year = {2024}, author = {Cho, JA and Jeon, S and Kwon, Y and Roh, YJ and Lee, CH and Kim, SJ}, title = {Comparative proteomics analysis of biofilms and planktonic cells of Enterococcus faecalis and Staphylococcus lugdunensis with contrasting biofilm-forming ability.}, journal = {PloS one}, volume = {19}, number = {5}, pages = {e0298283}, pmid = {38809833}, issn = {1932-6203}, mesh = {*Biofilms/growth &amp; development ; *Enterococcus faecalis/physiology/metabolism/genetics ; *Proteomics/methods ; *Staphylococcus lugdunensis/metabolism/genetics ; *Plankton/metabolism ; *Bacterial Proteins/metabolism/genetics ; Tandem Mass Spectrometry ; Chromatography, Liquid ; }, abstract = {Biofilms make it difficult to eradicate bacterial infections through antibiotic treatments and lead to numerous complications. Previously, two periprosthetic infection-related pathogens, Enterococcus faecalis and Staphylococcus lugdunensis were reported to have relatively contrasting biofilm-forming abilities. In this study, we examined the proteomics of the two microorganisms' biofilms using LC-MS/MS. The results showed that each microbe exhibited an overall different profile for differential gene expressions between biofilm and planktonic cells as well as between each other. Of a total of 929 proteins identified in the biofilms of E. faecalis, 870 proteins were shared in biofilm and planktonic cells, and 59 proteins were found only in the biofilm. In S. lugdunensis, a total of 1125 proteins were identified, of which 1072 proteins were found in common in the biofilm and planktonic cells, and 53 proteins were present only in the biofilms. The functional analysis for the proteins identified only in the biofilms using UniProt keywords demonstrated that they were mostly assigned to membrane, transmembrane, and transmembrane helix in both microorganisms, while hydrolase and transferase were found only in E. faecalis. Protein-protein interaction analysis using STRING-db indicated that the resulting networks did not have significantly more interactions than expected. GO term analysis exhibited that the highest number of proteins were assigned to cellular process, catalytic activity, and cellular anatomical entity. KEGG pathway analysis revealed that microbial metabolism in diverse environments was notable for both microorganisms. Taken together, proteomics data discovered in this study present a unique set of biofilm-embedded proteins of each microorganism, providing useful information for diagnostic purposes and the establishment of appropriately tailored treatment strategies. Furthermore, this study has significance in discovering the target candidate molecules to control the biofilm-associated infections of E. faecalis and S. lugdunensis.}, }
@article {pmid38809132, year = {2024}, author = {Wijesinghe, GK and Nissanka, M and Maia, FC and Rossini de Oliveira, T and Höfling, JF}, title = {Inverted amino acids reduce the adhesion and biofilm biomass of early oral colonizers.}, journal = {Dental and medical problems}, volume = {61}, number = {3}, pages = {385-390}, doi = {10.17219/dmp/160092}, pmid = {38809132}, issn = {2300-9020}, mesh = {*Biofilms/drug effects ; *Bacterial Adhesion/drug effects ; *Amino Acids/pharmacology/administration &amp; dosage ; *Streptococcus/drug effects ; Microbial Sensitivity Tests ; Humans ; Biomass ; Arginine/pharmacology ; Streptococcus gordonii/drug effects ; Anti-Bacterial Agents/pharmacology ; Streptococcus oralis/drug effects ; Leucine/pharmacology ; Tryptophan/pharmacology ; }, abstract = {BACKGROUND: Early colonizers adhere to the dental surface and facilitate the initial adhesion of secondary colonizers to form oral biofilms, which may cause oral infections.<br><br>OBJECTIVES: This study aimed to determine the antimicrobial, anti-adhesion and antibiofilm potency of inverted amino acids on early colonizer streptococci and their mixed species.<br><br>MATERIAL AND METHODS: The following test strains were used: Streptococcus gordonii (American Type Culture Collection (ATCC) 35105); Streptococcus mitis (ATCC 49456); Streptococcus oralis (ATCC 10557); Streptococcus salivarius (ATCC 7073); and Streptococcus sanguinis (ATCC BAA-1455). The concentration-dependent antimicrobial potency of d-alanine (d-ala), d-arginine (d-arg), d-leucine (d-leu), d-methionine (d-met), and d-tryptophan (d-try) was determined using the Clinical and Laboratory Standards Institute (CLSI) broth microdilution method with AlamarBlue modification. The adhesion of primary colonizers in the presence of 25-mM d-amino acids (dAAs) was assessed using the colony forming unit (CFU) assay. The CFU assay was conducted on 24-h flow cell bacterial biofilm models after exposure to 25-mM inverted dAAs.<br><br>RESULTS: No minimum inhibitory concentration (MIC) point was detected at any concentration tested. The minimum bactericidal concentration (MBC) point was not observed. The adhesion of S. mitis, S. oralis and mixed species was reduced by all tested dAAs. No adverse effects were observed on S. gordonii with any of the tested dAAs. The biofilm biomass of test strains under flow conditions was significantly reduced after a 5-min exposure to all tested dAAs at 25-mM concentration.<br><br>CONCLUSIONS: D-amino acids did not inhibit bacterial growth and did not show bactericidal or bacteriostatic effects on test strains at any concentration tested (ranging from 6.25 mM to 100 mM). However, dAAs effectively inhibit the adhesion of early colonizers, thereby preventing the formation of oral biofilm.}, }
@article {pmid38808771, year = {2024}, author = {Xiu, Y and Dai, Y and Yin, S and Wei, Q}, title = {Analysis of the Class 1 Integrons, Carbapenemase Genes and Biofilm Formation Genes Occurrence in Acinetobacter baumannii Clinical Isolates.}, journal = {Polish journal of microbiology}, volume = {73}, number = {2}, pages = {189-197}, pmid = {38808771}, issn = {2544-4646}, support = {EP-C-15-001/EPA/EPA/United States ; }, mesh = {*Acinetobacter baumannii/genetics/isolation &amp; purification/drug effects ; *beta-Lactamases/genetics ; *Integrons/genetics ; *Biofilms/growth &amp; development ; *Bacterial Proteins/genetics ; *Acinetobacter Infections/microbiology ; Humans ; Anti-Bacterial Agents/pharmacology ; Carbapenems/pharmacology ; Microbial Sensitivity Tests ; }, abstract = {Acinetobacter baumannii is a non-fermentative Gram-negative bacterium that can cause nosocomial infections in critically ill patients. Carbapenem-resistant A. baumannii (CRAB) has spread rapidly in clinical settings and has become a key concern. The main objective of this study was to identify the distribution of integrons and biofilm-formation-related virulence genes in CRAB isolates. A total of 269 A. baumannii isolates (219 isolates of CRAB and 50 isolates of carbapenem-sensitive A. baumannii (CSAB)) were collected. Carbapenemase genes (bla KPC, bla VIM, bla IMP, bla NDM, and bla OXA-23-like) and biofilm-formation-related virulence genes (abal, bfms, bap, and cusE) were screened with PCR. Class 1 integron was screened with PCR, and common promoters and gene cassette arrays were determined with restriction pattern analysis combined with primer walking sequencing. Whole-genome sequencing was conducted, and data were analyzed for a bla OXA-23-like-negative isolate. All 219 CRAB isolates were negative for bla KPC, bla VIM, bla IMP, and bla NDM, while bla OXA-23-like was detected in 218 isolates. The detection rates for abal, bfms, bap, and cusE in 219 CRAB were 93.15%, 63.93%, 88.13%, and 77.63%, respectively. Class 1 integron was detected in 75 CRAB (34.25%) and in 3 CSAB. The single gene cassette array aacA4-catB8-aadA1 with relatively strong PcH2 promoter was detected in class 1 integrons. The bla OXA-23-like-negative CRAB isolate was revealed to be a new sequence type (Oxford 3272, Pasteur 2520) carrying bla OXA-72, bla OXA-259, and bla ADC-26. In conclusion, bla OXA-23-like was the main reason for CRAB's resistance to carbapenems. A new (Oxford 3272, Pasteur 2520) CRAB sequence type carrying the bla OXA-72, bla OXA-259, and bla ADC-26 was reported.}, }
@article {pmid38808686, year = {2024}, author = {Werneburg, GT and Hettel, D and Adler, A and Mukherjee, SD and Goldman, HB and Rackley, RR and Zillioux, J and Martin, SE and Gill, BC and Shoskes, DA and Miller, AW and Vasavada, SP}, title = {Sacral neuromodulation device biofilm differs in the absence and presence of infection, harbors antibiotic resistance genes, and is reproducible in vitro.}, journal = {Neurourology and urodynamics}, volume = {43}, number = {7}, pages = {1479-1490}, doi = {10.1002/nau.25511}, pmid = {38808686}, issn = {1520-6777}, support = {//Society of Urodynamics, Female Pelvic Medicine and Urogenital Reconstruction Foundation/ ; }, mesh = {*Biofilms/drug effects ; Humans ; Female ; Middle Aged ; Male ; Aged ; Electric Stimulation Therapy/instrumentation ; Anti-Bacterial Agents/pharmacology ; Implantable Neurostimulators ; Sacrum/microbiology ; Prosthesis-Related Infections/microbiology ; Drug Resistance, Bacterial ; Bioreactors ; Rifampin/pharmacology ; Drug Resistance, Microbial ; Device Removal ; Urinary Bladder, Overactive/therapy/microbiology/physiopathology ; }, abstract = {INTRODUCTION/PURPOSE: Sacral neuromodulation (SNM) is effective therapy for overactive bladder refractory to oral therapies, and non-obstructive urinary retention. A subset of SNM devices is associated with infection requiring surgical removal. We sought to compare microbial compositions of explanted devices in the presence and absence of infection, by testing phase, and other clinical factors, and to investigate antibiotic resistance genes present in the biofilms. We analyzed resistance genes to antibiotics used in commercially-available anti-infective device coating/pouch formulations. We further sought to assess biofilm reconstitution by material type and microbial strain in vitro using a continuous-flow stir tank bioreactor, which mimics human tissue with an indwelling device. We hypothesized that SNM device biofilms would differ in composition by infection status, and genes encoding resistance to rifampin and minocycline would be frequently detected.<br><br>MATERIALS/METHODS: Patients scheduled to undergo removal or revision of SNM devices were consented per IRB-approved protocol (IRB 20-415). Devices were swabbed intraoperatively upon exposure, with controls and precautions to reduce contamination of the surrounding field. Samples and controls were analyzed with next-generation sequencing and RT-PCR, metabolomics, and culture-based approaches. Associations between microbial diversity or microbial abundance, and clinical variables were then analyzed using t-tests and ANOVA. Reconstituted biofilm deposition in vitro using the bioreactor was compared by microbial strain and material type using plate-based assays and scanning electron microscopy.<br><br>RESULTS: Thirty seven devices were analyzed, all of which harbored detectable microbiota. Proteobacteria, Firmicutes and Actinobacteriota were the most common phyla present overall. Beta-diversity differed in the presence versus absence of infection (p&#x2009;=&#x2009;0.014). Total abundance, based on normalized microbial counts, differed by testing phase (p&#x2009;<&#x2009;0.001), indication for placement (p&#x2009;=&#x2009;0.02), diabetes mellitus (p&#x2009;<&#x2009;0.001), cardiac disease (p&#x2009;=&#x2009;0.008) and history of UTI (p&#x2009;=&#x2009;0.008). Significant microbe-metabolite interaction networks were identified overall and in the absence of infection. 24% of biofilms harbored the tetA tetracycline/minocycline resistance gene and 53% harbored the rpoB rifampin resistance gene. Biofilm was reconstituted across tested strains and material types. Ceramic and titanium did not differ in biofilm deposition for any tested strain.<br><br>CONCLUSIONS: All analyzed SNM devices harbored microbiota. Device biofilm composition differed in the presence and absence of infection and by testing phase. Antibiotic resistance genes including to rifampin and tetracycline/minocycline, which are used in commercially-available anti-infective pouches, were frequently detected. Isolated organisms from SNM devices demonstrated the ability to reconstitute biofilm formation in vitro. Biofilm deposition was similar between ceramic and titanium, materials used in commercially-available SNM device casings. The findings and techniques used in this study together provide the basis for the investigation of the next generation of device materials and coatings, which may employ novel alternatives to traditional antibiotics. Such alternatives might include bacterial competition, quorum-sensing modulation, or antiseptic application, which could reduce infection risk without significantly selecting for antibiotic resistance.}, }
@article {pmid38808456, year = {2024}, author = {Zhou, Q and Jia, L and Li, Y and Wu, W and Wang, J}, title = {Significantly Enhanced Nitrate and Phosphorus Removal by Pyrite/Sawdust Composite-Driven Mixotrophic Denitrification with Boosted Electron Transfer: Comprehensive Evaluation of Water-Gas-Biofilm Phases during a Long-Term Study.}, journal = {Environmental science &amp; technology}, volume = {58}, number = {23}, pages = {10149-10161}, doi = {10.1021/acs.est.4c03677}, pmid = {38808456}, issn = {1520-5851}, mesh = {*Phosphorus/metabolism ; *Biofilms ; *Denitrification ; *Nitrates/metabolism ; Nitrogen/metabolism ; Electron Transport ; Iron ; Sulfides ; }, abstract = {Further reducing total nitrogen (TN) and total phosphorus (TP) in the secondary effluent needs to be realized effectively and in an eco-friendly manner. Herein, four pyrite/sawdust composite-based biofilters were established to treat simulated secondary effluent for 304 days. The results demonstrated that effluent TN and TP concentrations from biofilters under the optimal hydraulic retention time (HRT) of 3.5 h were stable at <2.0 and 0.1 mg/L, respectively, and no significant differences were observed between inoculated sludge sources. The pyrite/sawdust composite-based biofilters had low N2O, CH4, and CO2 emissions, and the effluent's DOM was mainly composed of five fluorescence components. Moreover, mixotrophic denitrifiers (Thiothrix) and sulfate-reducing bacteria (Desulfosporosinus) contributing to microbial nitrogen and sulfur cycles were enriched in the biofilm. Co-occurrence network analysis deciphered that Chlorobaculum and Desulfobacterales were key genera, which formed an obvious sulfur cycle process that strengthened the denitrification capacity. The higher abundances of genes encoding extracellular electron transport (EET) chains/mediators revealed that pyrite not only functioned as an electron conduit to stimulate direct interspecies electron transfer by flagella but also facilitated EET-associated enzymes for denitrification. This study comprehensively evaluates the water-gas-biofilm phases of pyrite/sawdust composite-based biofilters during a long-term study, providing an in-depth understanding of boosted electron transfer in pyrite-based mixotrophic denitrification systems.}, }
@article {pmid38805955, year = {2024}, author = {He, J and Lin, X and Zhang, D and Hu, H and Chen, X and Xu, F and Zhou, M}, title = {Wake biofilm up to enhance suicidal uptake of gallium for chronic lung infection treatment.}, journal = {Biomaterials}, volume = {310}, number = {}, pages = {122619}, doi = {10.1016/j.biomaterials.2024.122619}, pmid = {38805955}, issn = {1878-5905}, mesh = {*Biofilms/drug effects ; *Gallium/chemistry/pharmacology ; *Pseudomonas aeruginosa/drug effects/physiology ; Animals ; Pseudomonas Infections/drug therapy ; Anti-Bacterial Agents/pharmacology/therapeutic use ; Mice ; Lung/microbiology ; Quorum Sensing/drug effects ; Chronic Disease ; Iron/metabolism ; }, abstract = {The hypometabolic and nutrient-limiting condition of dormant bacteria inside biofilms reduces their susceptibility to antibacterial agents, making the treatment of biofilm-dominating chronic infections difficult. Herein, we demonstrate an intratracheal aerosolized maltohexaose-modified catalase-gallium integrated nanosystem that can 'wake up' dormant Pseudomonas aeruginosa biofilm to increase the metabolism and nutritional iron demand by reconciling the oxygen gradient. The activated bacteria then enhance suicidal gallium uptake since gallium acts as a 'Trojan horse' to mimic iron. The internalized gallium ions disrupt biofilms by interfering with the physiological processes of iron ion acquisition and utilization, biofilm formation, and quorum sensing. Furthermore, aerosol microsprayer administration and bacteria-specific maltohexaose modification enable accumulation at biofilm-infected lung and targeted release of gallium into bacteria to improve the therapeutic effect. This work provides a potential strategy for treating infection by reversing the dormant biofilm's resistance condition.}, }
@article {pmid38804136, year = {2024}, author = {Zhang, Q and Fu, J and Lin, H and Xuan, G and Zhang, W and Chen, L and Wang, G}, title = {Shining light on carbon dots: Toward enhanced antibacterial activity for biofilm disruption.}, journal = {Biotechnology journal}, volume = {19}, number = {5}, pages = {e2400156}, doi = {10.1002/biot.202400156}, pmid = {38804136}, issn = {1860-7314}, support = {32373172//National Natural-Science Foundation of China/ ; 22-3-7-cspz-4-nsh//Special Fund for the Qingdao Science and Technology Program of Public Wellbeing/ ; }, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Carbon/chemistry/pharmacology ; *Quantum Dots/chemistry ; Microbial Sensitivity Tests ; Reactive Oxygen Species/metabolism ; Light ; Singlet Oxygen/metabolism ; Polyethyleneimine/chemistry/pharmacology ; Citric Acid/chemistry/pharmacology ; Gram-Negative Bacteria/drug effects ; }, abstract = {In spite of tremendous efforts dedicated to addressing bacterial infections and biofilm formation, the post-antibiotic ear continues to witness a gap between the established materials and an easily accessible yet biocompatible antibacterial reagent. Here we show carbon dots (CDs) synthesized via a single hydrothermal process can afford promising antibacterial activity that can be further enhanced by exposure to light. By using citric acid and polyethyleneimine as the precursors, the photoluminescence CDs can be produced within a one-pot, one-step hydrothermal reaction in only 2 h. The CDs demonstrate robust antibacterial properties against both Gram-positive and Gram-negative bacteria and, notably, a considerable enhancement of antibacterial effect can be observed upon photo-irradiation. Mechanistic insights reveal that the CDs generate singlet oxygen ([1]O2) when exposed to light, leading to an augmented reactive oxygen species level. The approach for disruption of biofilms and inhibition of biofilm formation by using the CDs has also been established. Our findings present a potential solution to combat antibacterial resistance and offer a path to reduce dependence on traditional antibiotics.}, }
@article {pmid38800752, year = {2024}, author = {Winkelströter, LK and Bezirtzoglou, E and Tulini, FL}, title = {Editorial: Natural compounds and novel sources of antimicrobial agents for food preservation and biofilm control, volume II.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1412881}, pmid = {38800752}, issn = {1664-302X}, }
@article {pmid38800565, year = {2024}, author = {Cao, B and Ma, Y and Zhang, J and Wang, Y and Wen, Y and Yun Li,  and Wang, R and Cao, D and Zhang, R}, title = {Oxygen self-sufficient nanodroplet composed of fluorinated polymer for high-efficiently PDT eradicating oral biofilm.}, journal = {Materials today. Bio}, volume = {26}, number = {}, pages = {101091}, pmid = {38800565}, issn = {2590-0064}, abstract = {Oral biofilm is the leading cause of dental caries, which is difficult to completely eradicate because of the complicated biofilm structure. What's more, the hypoxia environment of biofilm and low water-solubility of conventional photosensitizers severely restrict the therapeutic effect of photodynamic therapy (PDT) for biofilm. Although conventional photosensitizers could be loaded in nanocarriers, it has reduced PDT effect because of aggregation-caused quenching (ACQ) phenomenon. In this study, we fabricated an oxygen self-sufficient nanodroplet (PFC/TPA@FNDs), which was composed of fluorinated-polymer (FP), perfluorocarbons (PFC) and an aggregation-induced emission (AIE) photosensitizer (Triphenylamine, TPA), to eradicate oral bacterial biofilm and whiten tooth. Fluorinated-polymer was synthesized by polymerizing (Dimethylamino)ethyl methacrylate, fluorinated monomer and 1-nonanol monomer. The nanodroplets could be protonated and behave strong positive charge under bacterial biofilm acid environment promoting nanodroplets deeply penetrating biofilm. More importantly, the nanodroplets had extremely high PFC and oxygen loading efficacy because of the hydrophobic affinity between fluorinated-polymer and PFC to relieve the hypoxia environment and enhance PDT effect. Additionally, compared with conventional ACQ photosensitizers loaded system, PFC/TPA@FNDs could behave superior PDT effect to ablate oral bacterial biofilm under light irradiation due to the unique AIE effect. In vivo caries animal model proved the nanodroplets could reduce dental caries area without damaging tooth structure. Ex vivo tooth whitening assay also confirmed the nanodroplets had similar tooth whitening ability compared with commercial tooth whitener H2O2, while did not disrupt the surface microstructure of tooth. This oxygen self-sufficient nanodroplet provides an alternative visual angle for oral biofilm eradication in biomedicine.}, }
@article {pmid38799795, year = {2024}, author = {Kabir, RB and Ahsan, T and Rahman, MF and Jobayer, M and Shamsuzzaman, SM}, title = {Biofilm-producing and specific antibiotic resistance genes in Pseudomonas aeruginosa isolated from patients admitted to a tertiary care hospital, Bangladesh.}, journal = {IJID regions}, volume = {11}, number = {}, pages = {100369}, pmid = {38799795}, issn = {2772-7076}, abstract = {OBJECTIVES: Biofilms are responsible for persistent infections and antimicrobial resistance. Pseudomonas aeruginosa was investigated with its ability to form biofilm by detecting genes responsible for producing biofilms and biofilm-specific antimicrobial resistance. The association between antibiotic resistance and biofilm was investigated.<br><br>METHODS: This cross-sectional study was conducted from July 2017 to December 2018. A total of 446 samples (infected burn, surgical wounds, and endotracheal aspirate) were collected from admitted patients of Dhaka Medical College and Hospital, Bangladesh. P. aeruginosa was isolated and identified by biochemical tests and polymerase chain reaction. Biofilm production by tissue culture plate method followed by detection of biofilm-producing genes (pqsA, pslA, pslD, pslH, pelA, lasR) and biofilm-specific antibiotic resistance genes (ndvB, PA1874, PA1876, PA1877) by polymerase chain reaction were done. Antibiotic susceptibility test was carried out by disk diffusion method; for colistin agar dilution method of minimal inhibitory concentration was followed.<br><br>RESULTS: Among 232 (52.02%) positive strains of P. aeruginosa, 24 (10.30%) produced biofilms in tissue culture plate. Among biofilm-producing genes, pqsA was the highest (79.17%). pslA and pelA were 70.83%, pslD 45.83%, pslH and lasR 37.5%. Among biofilm-specific antibiotic resistance genes, 16.67% were ndvB, and 8.33% were PA1874 and PA1877. Biofilm-forming strains were significantly resistant to colistin.<br><br>CONCLUSIONS: Detection of biofilm-forming genes may be a good tool for the evaluation of biofilm production, which will help in prompt and better management of chronic or device-associated infections.}, }
@article {pmid38799511, year = {2024}, author = {Yamamoto, K and Torigoe, S and Kobayashi, H}, title = {Formative evaluation and structural analysis of non-tuberculosis mycobacterial biofilm using material pieces.}, journal = {Cell surface (Amsterdam, Netherlands)}, volume = {11}, number = {}, pages = {100125}, pmid = {38799511}, issn = {2468-2330}, abstract = {Non-tuberculosis mycobacteria (NTM) can form biofilms on diverse artificial surfaces. In the present study, we induced NTM biofilm formation on materials used in various medical devices, evaluated the total amount of biofilm, and observed the ultrastructure by scanning electron microscopy.}, }
@article {pmid38798089, year = {2024}, author = {Hedayatipanah, M and Gholami, L and Farmany, A and Alikhani, MY and Hooshyarfard, A and Hashemiyan, FS}, title = {Green synthesis of silver nanoparticles and evaluation of their effects on the Porphyromonas gingivalis bacterial biofilm formation.}, journal = {Clinical and experimental dental research}, volume = {10}, number = {3}, pages = {e887}, pmid = {38798089}, issn = {2057-4347}, support = {//Hamadan University of Medical Sciences/ ; }, mesh = {*Porphyromonas gingivalis/drug effects ; *Biofilms/drug effects ; *Silver/pharmacology/chemistry ; *Metal Nanoparticles/chemistry ; *Anti-Bacterial Agents/pharmacology ; Green Chemistry Technology ; Propolis/pharmacology/chemistry ; Microbial Sensitivity Tests ; Dose-Response Relationship, Drug ; Humans ; }, abstract = {OBJECTIVE: This study aimed to evaluate the impact of silver nanoparticles (AgNPs) synthesized from propolis on the formation of Porphyromonas gingivalis biofilms.<br><br>MATERIAL AND METHODS: AgNPs were synthesized from propolis, and their inhibitory effect on P. gingivalis biofilm formation was assessed. Different concentrations of AgNPs (0.1%, 0.3%, and 0.5%) were tested to determine the dose-dependent antibacterial activity.<br><br>RESULTS: The results of this study indicated that AgNPs exhibited an inhibitory effect on P. gingivalis biofilm formation. The antibacterial activity of AgNPs was dose-dependent, with concentrations of 0.1%, 0.3%, and 0.5% showing effectiveness. Notably, the concentration of 0.5% demonstrated the most significant anti-biofilm formation activity.<br><br>CONCLUSION: The results of this study suggest that AgNPs synthesized from propolis have potential as an effective option for enhancing periodontal treatment outcomes. The inhibitory effect of AgNPs on P. gingivalis biofilm formation highlights their potential as alternative antimicrobial agents in the management of periodontal diseases.}, }
@article {pmid38798036, year = {2024}, author = {Sheu, JJ and Yeh, JN and Sung, PH and Chiang, JY and Chen, YL and Wang, YT and Yip, HK and Guo, J}, title = {ITRI Biofilm Prevented Thoracic Adhesion in Pigs That Received Myocardial Ischemic Induction Treated by Myocardial Implantation of EPCs and ECSW Treatment.}, journal = {Cell transplantation}, volume = {33}, number = {}, pages = {9636897241253144}, pmid = {38798036}, issn = {1555-3892}, mesh = {Animals ; Swine ; *Endothelial Progenitor Cells/metabolism/cytology ; *Myocardial Ischemia/therapy/complications ; *Swine, Miniature ; *Biofilms ; Extracorporeal Shockwave Therapy/methods ; Myocardium/metabolism/pathology ; Male ; }, abstract = {This study tested the hypothesis that ITRI Biofilm prevents adhesion of the chest cavity. Combined extracorporeal shock wave (ECSW) + bone marrow-derived autologous endothelial progenitor cell (EPC) therapy was superior to monotherapy for improving heart function (left ventricular ejection fraction [LVEF]) in minipigs with ischemic cardiomyopathy (IC) induced by an ameroid constrictor applied to the mid-left anterior descending artery. The minipigs (n = 30) were equally designed into group 1 (sham-operated control), group 2 (IC), group 3 (IC + EPCs/by directly implanted into the left ventricular [LV] myocardium; 3 [+]/3[-] ITRI Biofilm), group 4 (IC + ECSW; 3 [+]/[3] - ITRI Biofilm), and group 5 (IC + EPCs-ECSW; 3 [+]/[3] - ITRI Biofilm). EPC/ECSW therapy was administered by day 90, and the animals were euthanized, followed by heart harvesting by day 180. In vitro studies demonstrated that cell viability/angiogenesis/cell migratory abilities/mitochondrial concentrations were upregulated in EPCs treated with ECSW compared with those in EPCs only (all Ps < 0.001). The LVEF was highest in group 1/lowest in group 2/significantly higher in group 5 than in groups 3/4 (all Ps < 0.0001) by day 180, but there was no difference in groups 3/4. The adhesion score was remarkably lower in patients who received ITRI Biofilm treatment than in those who did not (all Ps <0.01). The protein expressions of oxidative stress (NOX-1/NOX-2/oxidized protein)/apoptotic (mitochondrial-Bax/caspase3/PARP)/fibrotic (TGF-β/Smad3)/DNA/mitochondria-damaged (γ-H2AX/cytosolic-cytochrome-C/p-DRP1), and heart failure/pressure-overload (BNP [brain natriuretic peptide]/β-MHC [beta myosin heavy chain]) biomarkers displayed a contradictory manner of LVEF among the groups (all Ps < 0.0001). The protein expression of endothelial biomarkers (CD31/vWF)/small-vessel density revealed a similar LVEF within the groups (all Ps < 0.0001). ITRI Biofilm treatment prevented chest cavity adhesion and was superior in restoring IC-related LV dysfunction when combined with EPC/ECSW therapy compared with EPC/ECSW therapy alone.}, }
@article {pmid38797913, year = {2024}, author = {Takahara, M and Hirayama, S and Futamata, H and Nakao, R and Tashiro, Y}, title = {Biofilm-derived membrane vesicles exhibit potent immunomodulatory activity in Pseudomonas aeruginosa PAO1.}, journal = {Microbiology and immunology}, volume = {68}, number = {7}, pages = {224-236}, doi = {10.1111/1348-0421.13156}, pmid = {38797913}, issn = {1348-0421}, support = {JPMJPR19H8//JST PRESTO/ ; JPMJCR19H2//JST CREST/ ; JP19H02920//JSPS KAKENHI/ ; JP19KK0394//JSPS KAKENHI/ ; JP22K19915//JSPS KAKENHI/ ; }, mesh = {*Pseudomonas aeruginosa/immunology/physiology ; *Biofilms/growth &amp; development ; *Cytokines/metabolism ; Mice ; Animals ; *Macrophages/immunology/microbiology ; Toll-Like Receptor 2/metabolism/genetics ; Toll-Like Receptor 4/metabolism ; Immunity, Innate ; Polymyxin B/pharmacology ; RAW 264.7 Cells ; Immunologic Factors/metabolism ; Extracellular Vesicles/immunology/metabolism ; Lipopolysaccharides ; RNA, Messenger/genetics/metabolism ; }, abstract = {Pathogenic bacteria form biofilms on epithelial cells, and most bacterial biofilms show increased production of membrane vesicles (MVs), also known as outer membrane vesicles in Gram-negative bacteria. Numerous studies have investigated the MVs released under planktonic conditions; however, the impact of MVs released from biofilms on immune responses remains unclear. This study aimed to investigate the characteristics and immunomodulatory activity of MVs obtained from both planktonic and biofilm cultures of Pseudomonas aeruginosa PAO1. The innate immune responses of macrophages to planktonic-derived MVs (p-MVs) and biofilm-derived MVs (b-MVs) were investigated by measuring the mRNA expression of proinflammatory cytokines. Our results showed that b-MVs induced a higher expression of inflammatory cytokines, including Il1b, Il6, and Il12p40, than p-MVs. The mRNA expression levels of Toll-like receptor 4 (Tlr4) differed between the two types of MVs, but not Tlr2. Polymyxin B significantly neutralized b-MV-mediated cytokine induction, suggesting that lipopolysaccharide of native b-MVs is the origin of the immune response. In addition, heat-treated or homogenized b-MVs induced the mRNA expression of cytokines, including Tnfa, Il1b, Il6, and Il12p40. Heat treatment of MVs led to increased expression of Tlr2 but not Tlr4, suggesting that TLR2 ligands play a role in detecting the pathogen-associated molecular patterns in lysed MVs. Taken together, our data indicate that potent immunomodulatory MVs are produced in P. aeruginosa biofilms and that this behavior could be a strategy for the bacteria to infect host cells. Furthermore, our findings would contribute to developing novel vaccines using MVs.}, }
@article {pmid38797020, year = {2024}, author = {Arrieta-Gisasola, A and Martínez-Ballesteros, I and Martinez-Malaxetxebarria, I and Garrido, V and Grilló, MJ and Bikandi, J and Laorden, L}, title = {Pan-Genome-Wide Association Study reveals a key role of the salmochelin receptor IroN in the biofilm formation of Salmonella Typhimurium and its monophasic variant 4,[5],12:i:.}, journal = {International journal of food microbiology}, volume = {419}, number = {}, pages = {110753}, doi = {10.1016/j.ijfoodmicro.2024.110753}, pmid = {38797020}, issn = {1879-3460}, mesh = {*Biofilms/growth &amp; development ; *Salmonella typhimurium/genetics/metabolism ; Animals ; Swine ; *Genome-Wide Association Study ; Humans ; *Bacterial Proteins/genetics/metabolism ; Iron/metabolism ; Phylogeny ; Salmonella Infections, Animal/microbiology ; Salmonella Infections/microbiology ; Gastroenteritis/microbiology ; Serogroup ; }, abstract = {Salmonella enterica subsp. enterica serovar Typhimurium variant 4,[5],12:i:- (so called S. 4,[5],12:i:-) has rapidly become one of the most prevalent serovars in humans in Europe, with clinical cases associated with foodborne from pork products. The mechanisms, genetic basis and biofilms relevance by which S. 4,[5],12:i:- maintains and spreads its presence in pigs remain unclear. In this study, we examined the genetic basis of biofilm production in 78 strains of S. 4,[5],12:i:- (n = 57) and S. Typhimurium (n = 21), from human gastroenteritis, food products and asymptomatic pigs. The former showed a lower Specific Biofilm Formation index (SBF) and distant phylogenetic clades, suggesting that the ability to form biofilms is not a crucial adaptation for the S. 4,[5],12:i:- emerging success in pigs. However, using a pan-Genome-Wide Association Study (pan-GWAS) we identified genetic determinants of biofilm formation, revealing 167 common orthologous groups and genes associated with the SBF. The analysis of annotated sequences highlighted specific genetic deletions in three chromosomal regions of S. 4,[5],12:i:- correlating with SBF values: i) the complete fimbrial operon stbABCDE widely recognized as the most critical factor involved in Salmonella adherence; ii) the hxlA, hlxB, and pgiA genes, which expression in S. Typhimurium is induced in the tonsils during swine infection, and iii) the entire iroA locus related to the characteristic deletion of the second-phase flagellar genomic region in S. 4,[5],12:i:-. Consequently, we further investigated the role of the iro-genes on biofilm by constructing S. Typhimurium deletion mutants in iroBCDE and iroN. While iroBCDE showed no significant impact, iroN clearly contributed to S. Typhimurium biofilm formation. In conclusion, the pan-GWAS approach allowed us to uncover complex interactions between genetic and phenotypic factors influencing biofilm formation in S. 4,[5],12:i:- and S. Typhimurium.}, }
@article {pmid38796070, year = {2024}, author = {Liu, T and Xu, H and Huang, T and Liu, G and Cao, H and Lin, Y and Li, Y and Li, Y and Yao, X}, title = {Fuzheng Touxie Jiedu Huayu Decoction inhibits the MexAB-OprM efflux pump and quorum sensing-mediated biofilm formation in difficult-to-treat multidrug resistance Pseudomonas aeruginosa.}, journal = {Journal of ethnopharmacology}, volume = {332}, number = {}, pages = {118365}, doi = {10.1016/j.jep.2024.118365}, pmid = {38796070}, issn = {1872-7573}, mesh = {*Pseudomonas aeruginosa/drug effects/physiology ; *Biofilms/drug effects/growth &amp; development ; *Quorum Sensing/drug effects ; *Drugs, Chinese Herbal/pharmacology ; *Bacterial Outer Membrane Proteins/metabolism ; *Anti-Bacterial Agents/pharmacology ; *Drug Resistance, Multiple, Bacterial/drug effects ; *Molecular Docking Simulation ; Microbial Sensitivity Tests ; Membrane Transport Proteins/metabolism/drug effects/genetics ; Ceftazidime/pharmacology ; }, abstract = {Fuzheng Touxie Jiedu Huayu Decoction (FTJHD) is a commonly used clinical formula that has been found effective in resisting multidrug resistance-Pseudomonas aeruginosa in previous in vivo and in vitro studies.<br><br>AIM OF THE STUDY: To investigate the antimicrobial effects of FTJHD and its drug-containing serum alone or in combination with ceftazidime on difficult-to-treat multidrug resistance-P. aeruginosa (DTMDR-P. aeruginosa).<br><br>MATERIALS AND METHODS: The antibacterial effects of FTJHD and its drug-containing alone or in combination with ceftazidime against DTMDR-P. aeruginosa were examined by the tube dilution method and bacterial growth curves. The changes in the bacterial ultrastructure were examined by transmission electron microscopy. The biofilm formation ability of bacteria was examined by crystal violet staining and scanning electron microscopy. The expression of the MexAB-OprM efflux pump and quorum sensing system genes were validated through quantitative polymerase chain reaction. Molecular docking was used to evaluate the interaction between active components and the MexAB-OprM efflux pump.<br><br>RESULTS: FTJHD-containing serums at 1-, 2-, 4-, and 8-fold concentrations reduced the minimal inhibitory concentration (MIC) of ceftazidime against DTMDR-P. aeruginosa from 128&#xa0;&#x3bc;g/mL to 64&#xa0;&#x3bc;g/mL. Sub-inhibitory concentrations of ceftazidime in combination with FTJHD and FTJHD-containing serum prolonged the lag period of bacterial growth and reduced bacterial numbers. Additionally, 1/2 MIC of ceftazidime combined with FTJHD-containing serum significantly inhibited the activity of the MexAB-OprM efflux pump and quorum sensing system, thus reducing biofilm formation while causing more severe damage to the bacteria. Molecular docking revealed a strong affinity of quercetin, baicalein, luteolin, kaempferol, and &#x3b2;-sitosterol for the efflux pump regulatory proteins OprM and MexR.<br><br>CONCLUSION: FTJHD can exert synergistic anti-DTMDR-P. aeruginosa effects with ceftazidime by inhibiting biofilm formation mediated by the MexAB-OprM efflux pump and quorum sensing.}, }
@article {pmid38794319, year = {2024}, author = {Aonofriesei, F}, title = {Surfactants' Interplay with Biofilm Development in Staphylococcus and Candida.}, journal = {Pharmaceutics}, volume = {16}, number = {5}, pages = {}, pmid = {38794319}, issn = {1999-4923}, abstract = {The capacity of micro-organisms to form biofilms is a pervasive trait in the microbial realm. For pathogens, biofilm formation serves as a virulence factor facilitating successful host colonization. Simultaneously, infections stemming from biofilm-forming micro-organisms pose significant treatment challenges due to their heightened resistance to antimicrobial agents. Hence, the quest for active compounds capable of impeding microbial biofilm development stands as a pivotal pursuit in biomedical research. This study presents findings concerning the impact of three surfactants, namely, polysorbate 20 (T20), polysorbate 80 (T80), and sodium dodecyl sulfate (SDS), on the initial stage of biofilm development in both Staphylococcus aureus and Candida dubliniensis. In contrast to previous investigations, we conducted a comparative assessment of the biofilm development capacity of these two taxonomically distant groups, predicated on their shared ability to reduce TTC. The common metabolic trait shared by S. aureus and C. dubliniensis in reducing TTC to formazan facilitated a simultaneous evaluation of biofilm development under the influence of surfactants across both groups. Our results revealed that surfactants could impede the development of biofilms in both species by disrupting the initial cell attachment step. The observed effect was contingent upon the concentration and type of compound, with a higher inhibition observed in culture media supplemented with SDS. At maximum concentrations (5%), T20 and T80 significantly curtailed the formation and viability of S. aureus and C. dubliniensis biofilms. Specifically, T20 inhibited biofilm development by 75.36% in S. aureus and 71.18% in C. dubliniensis, while T80 exhibited a slightly lower inhibitory effect, with values ranging between 66.68% (C. dubliniensis) and 65.54% (S. aureus) compared to the controls. Incorporating these two non-toxic surfactants into pharmaceutical formulations could potentially enhance the inhibitory efficacy of selected antimicrobial agents, particularly in external topical applications.}, }
@article {pmid38794143, year = {2024}, author = {Dimitrova, PD and Ivanova, V and Trendafilova, A and Paunova-Krasteva, T}, title = {Anti-Biofilm and Anti-Quorum-Sensing Activity of Inula Extracts: A Strategy for Modulating Chromobacterium violaceum Virulence Factors.}, journal = {Pharmaceuticals (Basel, Switzerland)}, volume = {17}, number = {5}, pages = {}, pmid = {38794143}, issn = {1424-8247}, support = {Research grant number KP-06-H41/8.//National Science Fund at the Ministry of Education and Science, Bulgaria./ ; }, abstract = {The formation of microbial biofilm is a self-organizing process among bacterial cells, regulated by quorum-sensing (QS) mechanisms, contributing to development of infections. These processes, either separately or in combination, significantly contribute to bacterial resistance to antibiotics and disinfectants. A novel approach to addressing the challenge of treating infections due to antibacterial resistance involves the use of plant metabolites. In recent years, there has been increasing recognition of different phytochemicals as potential modulators. In our study, we evaluated the synergistic effect of chloroform and methanol extracts from Inula species against key virulence factors, including biofilm formation, violacein production, and swarming motility. Each of the 11 examined plant extracts demonstrated the ability to reduce biofilms and pigment synthesis in C. violaceum. Two of the extracts from I. britannica exhibited significant anti-biofilm and anti-quorum-sensing effects with over 80% inhibition. Their inhibitory effect on violacein synthesis indicates their potential as anti-QS agents, likely attributed to their high concentration of terpenoids (triterpenoids, sesquiterpene lactones, and diterpenoids). Scanning electron microscopy revealed a notable reduction in biofilm biomass, along with changes in biofilm architecture and cell morphology. Additionally, fluorescence microscopy revealed the presence of metabolically inactive cells, indicating the potent activity of the extracts during treatment. These new findings underscore the effectiveness of the plant extracts from the genus Inula as potential anti-virulent agents against C. violaceum. They also propose a promising strategy for preventing or treating its biofilm formation.}, }
@article {pmid38794116, year = {2024}, author = {Bessalah, S and Faraz, A and Dbara, M and Khorcheni, T and Hammadi, M and Ajose, DJ and Saeed, SI}, title = {Antibacterial, Anti-Biofilm, and Anti-Inflammatory Properties of Gelatin-Chitosan-Moringa-Biopolymer-Based Wound Dressings towards Staphylococcus aureus and Escherichia coli.}, journal = {Pharmaceuticals (Basel, Switzerland)}, volume = {17}, number = {5}, pages = {}, pmid = {38794116}, issn = {1424-8247}, abstract = {In contemporary times, the sustained aspiration of bioengineering and biomedical applications is the progressive advancement of materials characterized by biocompatibility and biodegradability. The investigation of the potential applications of polymers as natural and non-hazardous materials has placed significant emphasis on their physicochemical properties. Thus, this study was designed to investigate the potential of gelatin-chitosan-moringa leaf extract (G-CH-M) as a novel biomaterial for biomedical applications. The wound-dressing G-CH-M biopolymer was synthesized and characterized. The blood haemolysis, anti-inflammatory, antioxidant, and antibacterial activities of the biopolymer were investigated against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacterial isolates. Our results showed that S. aureus swarming motility was drastically affected. However, the biopolymer had no significant effect on the swarming motility of E. coli. In addition, the biopolymer showed high antibacterial capacities, especially against S. aureus. Plasmid DNA was observed to be effectively protected from oxidative stresses by the biopolymer. Furthermore, the biopolymer exhibited greatly suppressed haemolysis (lower than 2%), notwithstanding the elevated concentration of 50 mg/mL. These results indicated that this novel biopolymer formulation could be further developed for wound care and contamination prevention.}, }
@article {pmid38792820, year = {2024}, author = {Cruickshank, D and Hamilton, DE and Iloba, I and Jensen, GS}, title = {Secreted Metabolites from Pseudomonas, Staphylococcus, and Borrelia Biofilm: Modulation of Immunogenicity by a Nutraceutical Enzyme and Botanical Blend.}, journal = {Microorganisms}, volume = {12}, number = {5}, pages = {}, pmid = {38792820}, issn = {2076-2607}, support = {not applicable//Researched Nutritionals/ ; }, abstract = {Bacterial biofilms are hardy, adaptable colonies, evading immune recognition while triggering and sustaining inflammation. The goals for this study were to present a method for testing the immunogenicity of secreted metabolites from pathogenic biofilm and to document whether biofilm treated with a nutraceutical enzyme and botanical blend (NEBB) showed evidence of reprogrammed bacterial metabolism, potentially becoming more recognizable to the immune system. We screened immune-modulating properties of metabolites from established biofilm from Pseudomonas aeruginosa (Pa), Stapholycoccus simulans (Ss), and Borrelia burgdorferi (Bb). Secreted metabolites significantly increased the cytokine production by human peripheral blood mononuclear cells, including Interleukin-1-beta (IL-1β), Interleukin-6 (IL-6), macrophage inflammatory protein-1-alpha (MIP-1α), tumor necrosis factor-alpha (TNF-α), interleukin-1 receptor antagonist (IL-1ra), and interleukin-10 (IL-10). Pa metabolites triggered the most robust increase in IL-1β, whereas Bb metabolites triggered the most robust increase in IL-10. NEBB-disrupted biofilm produced metabolites triggering altered immune modulation compared to metabolites from untreated biofilm. Metabolites from NEBB-disrupted biofilm triggered increased MIP-1α levels and reduced IL-10 levels, suggesting a reduced ability to suppress the recruitment of phagocytes compared to untreated biofilm. The results suggest that nutraceutical biofilm disruption offers strategies for inflammation management in chronic infectious illnesses. Further clinical studies are warranted to evaluate clinical correlations in infected human hosts.}, }
@article {pmid38792721, year = {2024}, author = {Monzón-Atienza, L and Bravo, J and Torrecillas, S and Gómez-Mercader, A and Montero, D and Ramos-Vivas, J and Galindo-Villegas, J and Acosta, F}, title = {An In-Depth Study on the Inhibition of Quorum Sensing by Bacillus velezensis D-18: Its Significant Impact on Vibrio Biofilm Formation in Aquaculture.}, journal = {Microorganisms}, volume = {12}, number = {5}, pages = {}, pmid = {38792721}, issn = {2076-2607}, support = {818367//EU Horizon 2020 AquaIMPACT (Genomic and nutritional innovations for genetically superior farmed fish to improve efficiency in European aquaculture)/ ; }, abstract = {Amid growing concerns about antibiotic resistance, innovative strategies are imperative in addressing bacterial infections in aquaculture. Quorum quenching (QQ), the enzymatic inhibition of quorum sensing (QS), has emerged as a promising solution. This study delves into the QQ capabilities of the probiotic strain Bacillus velezensis D-18 and its products, particularly in Vibrio anguillarum 507 communication and biofilm formation. Chromobacterium violaceum MK was used as a biomarker in this study, and the results confirmed that B. velezensis D-18 effectively inhibits QS. Further exploration into the QQ mechanism revealed the presence of lactonase activity by B. velezensis D-18 that degraded both long- and short-chain acyl homoserine lactones (AHLs). PCR analysis demonstrated the presence of a homologous lactonase-producing gene, ytnP, in the genome of B. velezensis D-18. The study evaluated the impact of B. velezensis D-18 on V. anguillarum 507 growth and biofilm formation. The probiotic not only controls the biofilm formation of V. anguillarum but also significantly restrains pathogen growth. Therefore, B. velezensis D-18 demonstrates substantial potential for preventing V. anguillarum diseases in aquaculture through its QQ capacity. The ability to disrupt bacterial communication and control biofilm formation positions B. velezensis D-18 as a promising eco-friendly alternative to conventional antibiotics in managing bacterial diseases in aquaculture.}, }
@article {pmid38792710, year = {2024}, author = {Perpetuini, G and Rossetti, AP and Rapagnetta, A and Arfelli, G and Prete, R and Tofalo, R}, title = {Wine Barrel Biofilm as a Source of Yeasts with Non-Conventional Properties.}, journal = {Microorganisms}, volume = {12}, number = {5}, pages = {}, pmid = {38792710}, issn = {2076-2607}, support = {Project Code: ECS00000041; Project CUP: C43C22000380007//European Union-Next Generation EU/ ; }, abstract = {This study investigated the main microbial groups characterizing the interior surface of oak barrels from different years (1890, 1895, 1920, 1975, 2008) used in the production of vino cotto. The yeasts were characterized for the following properties: γ-aminobutyric acid (GABA) production, antioxidant activity, air-liquid interfacial biofilm formation, and anthocyanin adsorption capacity. Community-level physiological profile analysis revealed that the microbial communities inside the barrels used the tested carbon sources in different manners. The following yeast species were identified: Millerozyma farinosa, Zygosaccharomyces bisporus, Wickerhamiella versatilis, Zygosaccharomyces bailii, Starmerella lactis-condensi, and Zygosaccharomyces rouxii. All the strains were able to produce GABA, and S. lactis-condensi, Z. bisporus and Z. rouxii were the highest producers (more than 600 mg/L). The Z. rouxii and Z. bailii strains showed the highest antioxidant activity. Only seven strains out of ten M. farinosa formed air-liquid interfacial biofilm. None of the M. farinosa strains adsorbed anthocyanins on their cell wall. The other strains adsorbed anthocyanins in a strain-dependent way, and the highest adsorption was observed for the W. versatilis strains. The yeasts isolated in this study could be used to increase the functional properties and the quality of fermented foods and beverages.}, }
@article {pmid38792672, year = {2024}, author = {Santana, GB and Quelemes, PV and da Silva Neta, ER and de Lima, SG and Vale, GC}, title = {Chemical Characterization and Effect of a Lactobacilli-Postbiotic on Streptococcus mutans Biofilm In Vitro.}, journal = {Microorganisms}, volume = {12}, number = {5}, pages = {}, pmid = {38792672}, issn = {2076-2607}, support = {ED 08/2018 PRONEM//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado do Piau&#xed;/ ; 421385/2023-5//National Council for Scientific and Technological Development/ ; }, abstract = {Postbiotic is the term used to define the soluble factors, metabolic products, or byproducts released by live probiotic bacteria or after its lysis. The objective of this study was to carry out the chemical characterization of the postbiotic of Lacticaseibacillus rhamnosus LR-32 and to evaluate its in vitro effect on the development of the Streptococcus mutans biofilm. After the cultivation of the probiotic strain, the postbiotic was extracted by centrifuging the culture and filtering the supernatant. This postbiotic was characterized by using gas chromatography coupled with mass spectrometry (GC-MS), and then it was used to determine the growth inhibition of S. mutans in its planktonic form; additionally, its effects on the following parameters in 48 h biofilm were evaluated: viable bacteria, dry weight, and gene expression of glucosyltransferases and VicR gene. The control group consisted of the biofilm without any treatment. A paired t-test was performed for statistical analysis, with the p-value set at 5%. Seventeen compounds of various chemical classes were identified in the postbiotic, including sugars, amino acids, vitamins, and acids. The treatment with the postbiotic led to an inhibition of the growth of S. mutans in its planktonic form, as well as a decrease in the number of viable bacteria, reduction in dry weight, and a negative regulation of the gene expression of gtfB, gtfC, gtfD, and vicR in its biofilm state, compared with the nontreated group (p < 0.05). The postbiotic of L. rhamnosus impaired the development of S. mutans biofilm.}, }
@article {pmid38791239, year = {2024}, author = {Shao, L and Shen, Z and Li, M and Guan, C and Fan, B and Chai, Y and Zhao, Y}, title = {ccdC Regulates Biofilm Dispersal in Bacillus velezensis FZB42.}, journal = {International journal of molecular sciences}, volume = {25}, number = {10}, pages = {}, pmid = {38791239}, issn = {1422-0067}, mesh = {*Biofilms/growth &amp; development ; *Bacillus/physiology/genetics ; *Bacterial Proteins/genetics/metabolism ; Cyclic GMP/metabolism/analogs &amp; derivatives ; Gene Expression Regulation, Bacterial ; Rhizosphere ; }, abstract = {Bacillus velezensis FZB42 is a plant growth-promoting rhizobacterium (PGPR) and a model microorganism for biofilm studies. Biofilms are required for the colonization and promotion of plant growth in the rhizosphere. However, little is known about how the final stage of the biofilm life cycle is regulated, when cells regain their motility and escape the mature biofilm to spread and colonize new niches. In this study, the non-annotated gene ccdC was found to be involved in the process of biofilm dispersion. We found that the ccdC-deficient strain maintained a wrinkled state at the late stage of biofilm formation in the liquid-gas interface culture, and the bottom solution showed a clear state, indicating that no bacterial cells actively escaped, which was further evidenced by the formation of a cellular ring (biofilm pellicle) located on top of the preformed biofilm. It can be concluded that dispersal, a biofilm property that relies on motility proficiency, is also positively affected by the unannotated gene ccdC. Furthermore, we found that the level of cyclic diguanylate (c-di-GMP) in the ccdC-deficient strain was significantly greater than that in the wild-type strain, suggesting that B. velezensis exhibits a similar mechanism by regulating the level of c-di-GMP, the master regulator of biofilm formation, dispersal, and cell motility, which controls the fitness of biofilms in Pseudomonas aeruginosain. In this study, we investigated the mechanism regulating biofilm dispersion in PGPR.}, }
@article {pmid38791017, year = {2024}, author = {Kim, HE}, title = {Influence of Biofilm Maturity on the Antibacterial Efficacy of Cold Atmospheric Plasma in Oral Microcosm Biofilms.}, journal = {Biomedicines}, volume = {12}, number = {5}, pages = {}, pmid = {38791017}, issn = {2227-9059}, support = {2022R1F1A1064357//National Research Foundation of Korea/ ; }, abstract = {As biofilms mature, biomass and extracellular polysaccharide (EPS) content increases, enhancing pathogenicity. Therefore, this study aimed to evaluate the antibacterial efficacy of cold atmospheric plasma (CAP) against oral microcosm biofilms and the influence of biofilm maturity on treatment. Oral microcosm biofilms were cultured on hydroxyapatite disks for 2 and 6 days. Based on the treatment and biofilm maturity, these were subsequently allocated into six groups (N = 19 each): Groups 1 and 2 were incubated with distilled water for 1 min; Groups 3 and 4 were treated with CAP for 2 min, and Groups 5 and 6 were treated with 0.12% chlorhexidine gluconate for 1 min. Groups 1, 3, and 5 represent 2-day biofilms, and Groups 2, 4, and 6 represent 6-day biofilms. Treatments were repeated daily for 5 days. Antibacterial efficacy was analyzed by measuring oral biofilms' red fluorescence intensity (RatioR/G) and quantifying EPS content and bacterial viability. The RatioR/G was 1.089-fold and 1.104-fold higher in Groups 4 and 6 than in Groups 3 and 5 following antibacterial treatment, respectively (p < 0.001). EPS content increased by 1.71-fold in Group 6 than in Group 5 (p < 0.001). Bacterial survival rate was the lowest in Group 3 (p = 0.005). These findings underscore the relevance of CAP treatment in maintaining antibacterial efficacy regardless of the biofilm development stage, highlighting its potential utility in oral care.}, }
@article {pmid38790956, year = {2024}, author = {Rasheed, R and Bhat, A and Singh, B and Tian, F}, title = {Biogenic Synthesis of Selenium and Copper Oxide Nanoparticles and Inhibitory Effect against Multi-Drug Resistant Biofilm-Forming Bacterial Pathogens.}, journal = {Biomedicines}, volume = {12}, number = {5}, pages = {}, pmid = {38790956}, issn = {2227-9059}, abstract = {Antimicrobial resistance (AMR), caused by microbial infections, has become a major contributor to morbid rates of mortality worldwide and a serious threat to public health. The exponential increase in resistant pathogen strains including Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) poses significant hurdles in the health sector due to their greater resistance to traditional treatments and medicines. Efforts to tackle infectious diseases caused by resistant microbes have prompted the development of novel antibacterial agents. Herein, we present selenium and copper oxide monometallic nanoparticles (Se-MMNPs and CuO-MMNPs), characterized using various techniques and evaluated for their antibacterial potential via disc diffusion, determination of minimum inhibitory concentration (MIC), antibiofilm, and killing kinetic action. Dynamic light scattering (DLS), scanning electron microscopy (SEM/EDX), and X-ray diffraction (XRD) techniques confirmed the size-distribution, spherical-shape, stability, elemental composition, and structural aspects of the synthesized nanoparticles. The MIC values of Se-MMNPs and CuO-MMNPs against S. aureus and E. coli were determined to be 125 μg/mL and 100 μg/mL, respectively. Time-kill kinetics studies revealed that CuO-MMNPs efficiently mitigate the growth of S. aureus and E. coli within 3 and 3.5 h while Se-MMNPs took 4 and 5 h, respectively. Moreover, CuO-MMNPs demonstrated better inhibition compared to Se-MMNPs. Overall, the proposed materials exhibited promising antibacterial activity against S. aureus and E. coli pathogens.}, }
@article {pmid38789905, year = {2024}, author = {Algburi, AR and Jassim, SM and Popov, IV and Weeks, R and Chikindas, ML}, title = {Lactobacillus acidophilus VB1 co-aggregates and inhibits biofilm formation of chronic otitis media-associated pathogens.}, journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]}, volume = {55}, number = {3}, pages = {2581-2592}, pmid = {38789905}, issn = {1678-4405}, mesh = {*Lactobacillus acidophilus/drug effects/physiology ; *Biofilms/drug effects/growth &amp; development ; *Anti-Bacterial Agents/pharmacology ; *Otitis Media/microbiology ; *Microbial Sensitivity Tests ; *Ciprofloxacin/pharmacology ; *Probiotics/pharmacology ; Humans ; Bacteria/drug effects/isolation &amp; purification/classification ; Chronic Disease ; Pseudomonas aeruginosa/drug effects/physiology ; Antibiosis ; Staphylococcus aureus/drug effects/physiology ; }, abstract = {This study aims to evaluate the antibacterial activity of Lactobacillus acidophilus, alone and in combination with ciprofloxacin, against otitis media-associated bacteria. L. acidophilus cells were isolated from Vitalactic B (VB), a commercially available probiotic product containing two lactobacilli species, L. acidophilus and Lactiplantibacillus (formerly Lactobacillus) plantarum. The pathogenic bacterial samples were provided by Al-Shams Medical Laboratory (Baqubah, Iraq). Bacterial identification and antibiotic susceptibility testing for 16 antibiotics were performed using the VITEK2 system. The minimum inhibitory concentration of ciprofloxacin was also determined. The antimicrobial activity of L. acidophilus VB1 cell-free supernatant (La-CFS) was evaluated alone and in combination with ciprofloxacin using a checkerboard assay. Our data showed significant differences in the synergistic activity when La-CFS was combined with ciprofloxacin, in comparison to the use of each compound alone, against Pseudomonas aeruginosa SM17 and Proteus mirabilis SM42. However, an antagonistic effect was observed for the combination against Staphylococcus aureus SM23 and Klebsiella pneumoniae SM9. L. acidophilus VB1 was shown to significantly co-aggregate with the pathogenic bacteria, and the highest co-aggregation percentage was observed after 24 h of incubation. The anti-biofilm activities of CFS and biosurfactant (BS) of L. acidophilus VB1 were evaluated, and we found that the minimum biofilm inhibitory concentration that inhibits 50% of bacterial biofilm (MBIC50) of La-CFS was significantly lower than MBIC50 of La-BS against the tested pathogenic bacterial species. Lactobacillus acidophilus, isolated from Vitane Vitalactic B capsules, demonstrated promising antibacterial and anti-biofilm activities against otitis media pathogens, highlighting its potential as an effective complementary/alternative therapeutic strategy to control bacterial ear infections.}, }
@article {pmid38788981, year = {2024}, author = {Ketagoda, DHK and Varga, P and Fitzsimmons, TR and Moore, NE and Weyrich, LS and Zilm, PS}, title = {Development of an in vitro biofilm model of the human supra-gingival microbiome for Oral microbiome transplantation.}, journal = {Journal of microbiological methods}, volume = {223}, number = {}, pages = {106961}, doi = {10.1016/j.mimet.2024.106961}, pmid = {38788981}, issn = {1872-8359}, mesh = {*Biofilms/growth &amp; development ; Humans ; *Microbiota ; *Mouth/microbiology ; *Bacteria/genetics/classification/isolation &amp; purification ; Gingiva/microbiology ; Dental Plaque/microbiology ; Saliva/microbiology ; Microscopy, Confocal ; High-Throughput Nucleotide Sequencing ; Fecal Microbiota Transplantation/methods ; Dental Caries/microbiology/therapy ; }, abstract = {The high prevalence of dental caries and periodontal disease place a significant burden on society, both socially and economically. Recent advances in genomic technologies have linked both diseases to shifts in the oral microbiota - a community of >700 bacterial species that live within the mouth. The development of oral microbiome transplantation draws on the success of fecal microbiome transplantation for the treatment of gut pathologies associated with disease. Many current in vitro oral biofilm models have been developed but do not fully capture the complexity of the oral microbiome which is required for successful OMT. To address this, we developed an in vitro biofilm system that maintained an oral microbiome with 252 species on average over 14 days. Six human plaque samples were grown in 3D printed flow cells on hydroxyapatite discs using artificial saliva medium (ASM). Biofilm composition and growth were monitored by high throughput sequencing and confocal microscopy/SEM, respectively. While a significant drop in bacterial diversity occurred, up to 291 species were maintained in some flow cells over 14 days with 70% viability grown with ASM. This novel in vitro biofilm model represents a marked improvement on existing oral biofilm systems and provides new opportunities to develop oral microbiome transplant therapies.}, }
@article {pmid38788980, year = {2024}, author = {Buckner, E and Buckingham-Meyer, K and Miller, LA and Parker, AE and Jones, CJ and Goeres, DM}, title = {Coupon position does not affect Pseudomonas aeruginosa and Staphylococcus aureus biofilm densities in the CDC biofilm reactor.}, journal = {Journal of microbiological methods}, volume = {223}, number = {}, pages = {106960}, doi = {10.1016/j.mimet.2024.106960}, pmid = {38788980}, issn = {1872-8359}, mesh = {*Biofilms/growth &amp; development ; *Staphylococcus aureus/physiology/growth &amp; development ; *Pseudomonas aeruginosa/physiology/growth &amp; development ; *Bioreactors/microbiology ; }, abstract = {The CDC Biofilm Reactor method is the standard biofilm growth protocol for the validation of US Environmental Protection Agency biofilm label claims. However, no studies have determined the effect of coupon orientation within the reactor on biofilm growth. If positional effects have a statistically significant impact on biofilm density, they should be accounted for in the experimental design. Here, we isolate and quantify biofilms from each possible coupon surface in the reactor to quantitatively determine the positional effects in the CDC Biofilm Reactor. The results showed no statistically significant differences in viable cell density across different orientations and vertical positions in the reactor. Pseudomonas aeruginosa log densities were statistically equivalent among all coupon heights and orientations. While the Staphylococcus aureus cell growth showed no statistically significant differences, the densities were not statistically equivalent among all coupon heights and orientations due to the variability in the data. Structural differences were observed between biofilms on the high-shear baffle side of the reactor compared to the lower shear glass side of the reactor. Further studies are required to determine whether biofilm susceptibility to antimicrobials differs based on structural differences attributed to orientation.}, }
@article {pmid38788803, year = {2024}, author = {Sun, L and Ayele Shewa, W and Bossy, K and Dagnew, M}, title = {Partial denitrification in rope-type biofilm reactors: Performance, kinetics, and microflora using internal vs. external carbon sources.}, journal = {Bioresource technology}, volume = {404}, number = {}, pages = {130890}, doi = {10.1016/j.biortech.2024.130890}, pmid = {38788803}, issn = {1873-2976}, mesh = {*Biofilms ; *Denitrification ; *Bioreactors ; *Carbon ; *Wastewater/microbiology/chemistry ; Kinetics ; Nitrites/metabolism ; Hydrogen-Ion Concentration ; }, abstract = {Stable nitrite accumulation through partial denitrification (PDN) represents an efficient pathway to support the anammox process, but limited studies explored the internal wastewater carbon sources and biofilm processes. This study assessed the viability of the PDN process, biofilm community evolution, and functional enzyme formation in rope-type biofilm media reactors using primary effluent (PE) and anaerobically pretreated wastewater carbon sources for the first time. Comparison was made with external carbon (acetate) under varied pH and biofilm thicknesses, maintaining a favourable sCOD: NO3-N ratio of 3. The wastewater's internal carbon resulted in thinner biofilms; nevertheless, modest nitrite accumulation (0.24 g/m[2]/d) occurred only at elevated pH. The highest nitrite accumulation (0.79 g/m[2]/d) was exhibited in the biofilm thickness-controlled acetate-fed reactor, featuring porous biofilms dominated by denitrifier Thauera (10.24 %) and imbalance between Nar, Nap, and Nir reductases. Using internal wastewater carbon sources offers a sustainable avenue for adopting the PDN process in full-scale application.}, }
@article {pmid38787336, year = {2024}, author = {Murphy, C and Banasiewicz, T and Duteille, F and Ferrando, PM and Jerez González, JA and Koullias, G and Long, Z and Nasur, R and Salazar Trujillo, MA and Bassetto, F and Dunk, AM and Iafrati, M and Jawień, A and Matsumura, H and O'Connor, L and Sanchez, V and Wu, J}, title = {A proactive healing strategy for tackling biofilm-based surgical site complications: Wound Hygiene Surgical.}, journal = {Journal of wound care}, volume = {33}, number = {Sup5a}, pages = {S1-S30}, doi = {10.12968/jowc.2024.33.Sup5c.S1}, pmid = {38787336}, issn = {0969-0700}, mesh = {Humans ; *Biofilms ; *Surgical Wound Infection/prevention &amp; control ; *Wound Healing ; }, }
@article {pmid38787246, year = {2024}, author = {Bouhrour, N and Nibbering, PH and Bendali, F}, title = {Medical Device-Associated Biofilm Infections and Multidrug-Resistant Pathogens.}, journal = {Pathogens (Basel, Switzerland)}, volume = {13}, number = {5}, pages = {}, pmid = {38787246}, issn = {2076-0817}, abstract = {Medical devices such as venous catheters (VCs) and urinary catheters (UCs) are widely used in the hospital setting. However, the implantation of these devices is often accompanied by complications. About 60 to 70% of nosocomial infections (NIs) are linked to biofilms. The main complication is the ability of microorganisms to adhere to surfaces and form biofilms which protect them and help them to persist in the host. Indeed, by crossing the skin barrier, the insertion of VC inevitably allows skin flora or accidental environmental contaminants to access the underlying tissues and cause fatal complications like bloodstream infections (BSIs). In fact, 80,000 central venous catheters-BSIs (CVC-BSIs)-mainly occur in intensive care units (ICUs) with a death rate of 12 to 25%. Similarly, catheter-associated urinary tract infections (CA-UTIs) are the most commonlyhospital-acquired infections (HAIs) worldwide.These infections represent up to 40% of NIs.In this review, we present a summary of biofilm formation steps. We provide an overview of two main and important infections in clinical settings linked to medical devices, namely the catheter-asociated bloodstream infections (CA-BSIs) and catheter-associated urinary tract infections (CA-UTIs), and highlight also the most multidrug resistant bacteria implicated in these infections. Furthermore, we draw attention toseveral useful prevention strategies, and advanced antimicrobial and antifouling approaches developed to reduce bacterial colonization on catheter surfaces and the incidence of the catheter-related infections.}, }
@article {pmid38787042, year = {2024}, author = {Lysitsas, M and Triantafillou, E and Chatzipanagiotidou, I and Antoniou, K and Spyrou, V and Billinis, C and Valiakos, G}, title = {Phenotypic Investigation and Detection of Biofilm-Associated Genes in Acinetobacter baumannii Isolates, Obtained from Companion Animals.}, journal = {Tropical medicine and infectious disease}, volume = {9}, number = {5}, pages = {}, pmid = {38787042}, issn = {2414-6366}, abstract = {Bacteria of the genus Acinetobacter, especially Acinetobacter baumannii (Ab), have emerged as pathogens of companion animals during the last two decades and are commonly associated with hospitalization and multidrug resistance. A critical factor for the distribution of relevant strains in healthcare facilities, including veterinary facilities, is their adherence to both biotic and abiotic surfaces and the production of biofilms. A group of 41 A. baumannii isolates obtained from canine and feline clinical samples in Greece was subjected to phenotypic investigation of their ability to produce biofilms using the tissue culture plate (TCP) method. All of them (100%) produced biofilms, while 23 isolates (56.1%) were classified as strong producers, 11 (26.8%) as moderate producers, and 7 (17.1%) as weak producers. A correlation between the MDR and XDR phenotypes and weak or moderate biofilm production was identified. Moreover, the presence of four biofilm-associated genes bap, blaPER, ompA, and csuE was examined by PCR, and they were detected in 100%, 65.9%, 97.6%, and 95.1% of the strains respectively. All isolates carried at least two of the investigated genes, whereas most of the strong biofilm producers carried all four genes. In conclusion, the spread and persistence of biofilm-producing Ab strains in veterinary facilities is a matter of concern, since they are regularly obtained from infected animals, indicating their potential as challenging pathogens for veterinarians due to multidrug resistance and tolerance in conventional eradication measures. Furthermore, considering that companion animals can act as reservoirs of relevant strains, public health concerns emerge.}, }
@article {pmid38786943, year = {2024}, author = {Zhang, Z and Huang, Z and Li, H and Wang, D and Yao, Y and Dong, K}, title = {Impact of Nitrate on the Removal of Pollutants from Water in Reducing Gas-Based Membrane Biofilm Reactors: A Review.}, journal = {Membranes}, volume = {14}, number = {5}, pages = {}, pmid = {38786943}, issn = {2077-0375}, support = {2022GXNSFFA035033//the Guangxi Natural Science Foundation Outstanding Youth Fund/ ; 51878197//the National Natural Science Foundation of China/ ; guikeneng 2301Z003//the Research funds of The Guangxi Key Laboratory of Theory and Technology for Environmental Pollution Control/ ; }, abstract = {The membrane biofilm reactor (MBfR) is a novel wastewater treatment technology, garnering attention due to its high gas utilization rate and effective pollutant removal capability. This paper outlines the working mechanism, advantages, and disadvantages of MBfR, and the denitrification pathways, assessing the efficacy of MBfR in removing oxidized pollutants (sulfate (SO4[-]), perchlorate (ClO4[-])), heavy metal ions (chromates (Cr(VI)), selenates (Se(VI))), and organic pollutants (tetracycline (TC), p-chloronitrobenzene (p-CNB)), and delves into the role of related microorganisms. Specifically, through the addition of nitrates (NO3[-]), this paper analyzes its impact on the removal efficiency of other pollutants and explores the changes in microbial communities. The results of the study show that NO[3-] inhibits the removal of other pollutants (oxidizing pollutants, heavy metal ions and organic pollutants), etc., in the simultaneous removal of multiple pollutants by MBfR.}, }
@article {pmid38786716, year = {2024}, author = {Pires, ACMDS and Carvalho, AR and Vaso, CO and Mendes-Giannini, MJS and Singulani, JL and Fusco-Almeida, AM}, title = {Influence of Zinc on Histoplasma capsulatum Planktonic and Biofilm Cells.}, journal = {Journal of fungi (Basel, Switzerland)}, volume = {10}, number = {5}, pages = {}, pmid = {38786716}, issn = {2309-608X}, support = {16/11836-0//S&#xe3;o Paulo Research Foundation/ ; 2020/15586-4//S&#xe3;o Paulo Research Foundation/ ; 2017/06658-9//S&#xe3;o Paulo Research Foundation/ ; 142110/2019//National Council for Scientific and Technological Development/ ; 88887.6000545/2021-00//Coordena&#xe7;&#xe3;o de Aperfeicoamento de Pessoal de N&#xed;vel Superior/ ; 88887.500765/2020-00//Coordena&#xe7;&#xe3;o de Aperfeicoamento de Pessoal de N&#xed;vel Superior/ ; PDI-UNESP-0//Pr&#xf3;-Reitoria de P&#xf3;s-Gradua&#xe7;&#xe3;o (PROPG)/ ; }, abstract = {Histoplasma capsulatum causes a fungal respiratory disease. Some studies suggest that the fungus requires zinc to consolidate the infection. This study aimed to investigate the influence of zinc and the metal chelator TPEN on the growth of Histoplasma in planktonic and biofilm forms. The results showed that zinc increased the metabolic activity, cell density, and cell viability of planktonic growth. Similarly, there was an increase in biofilm metabolic activity but no increase in biomass or extracellular matrix production. N'-N,N,N,N-tetrakis-2-pyridylmethylethane-1,2 diamine (TPEN) dramatically reduced the same parameters in the planktonic form and resulted in a decrease in metabolic activity, biomass, and extracellular matrix production for the biofilm form. Therefore, the unprecedented observations in this study highlight the importance of zinc ions for the growth, development, and proliferation of H. capsulatum cells and provide new insights into the role of metal ions for biofilm formation in the dimorphic fungus Histoplasma, which could be a potential therapeutic strategy.}, }
@article {pmid38786632, year = {2024}, author = {Yun, J and Burrow, MF and Matinlinna, JP and Ding, H and Chan, SMR and Tsoi, JKH and Wang, Y}, title = {Design of Multi-Functional Bio-Safe Dental Resin Composites with Mineralization and Anti-Biofilm Properties.}, journal = {Journal of functional biomaterials}, volume = {15}, number = {5}, pages = {}, pmid = {38786632}, issn = {2079-4983}, support = {2020B1515120062//the Key Project of Regional Collaboration Research Grant of Guangdong Basic and Applied Basic Research Grant/ ; }, abstract = {This study aims to develop multi-functional bio-safe dental resin composites with capabilities for mineralization, high in vitro biocompatibility, and anti-biofilm properties. To address this issue, experimental resin composites consisting of UDMA/TEGDMA-based dental resins and low quantities (1.9, 3.8, and 7.7 vol%) of 45S5 bioactive glass (BAG) particles were developed. To evaluate cellular responses of resin composites, MC3T3-E1 cells were (1) exposed to the original composites extracts, (2) cultured directly on the freshly cured resin composites, or (3) cultured on preconditioned composites that have been soaked in deionized water (DI water), a cell culture medium (MEM), or a simple HEPES-containing artificial remineralization promotion (SHARP) solution for 14 days. Cell adhesion, cell viability, and cell differentiation were, respectively, assessed. In addition, the anti-biofilm properties of BAG-loaded resin composites regarding bacterial viability, biofilm thickness, and biofilm morphology, were assessed for the first time. In vitro biological results demonstrated that cell metabolic activity and ALP expression were significantly diminished when subjected to composite extracts or direct contact with the resin composites containing BAG fillers. However, after the preconditioning treatments in MEM and SHARP solutions, the biomimetic calcium phosphate minerals on 7.7 vol% BAG-loaded composites revealed unimpaired or even better cellular processes, including cell adhesion, cell proliferation, and early cell differentiation. Furthermore, resin composites with 1.9, 3.8, and 7.7 vol% BAG could not only reduce cell viability in S. mutans biofilm on the composite surface but also reduce the biofilm thickness and bacterial aggregations. This phenomenon was more evident in BAG7.7 due to the high ionic osmotic pressure and alkaline microenvironment caused by BAG dissolution. This study concludes that multi-functional bio-safe resin composites with mineralization and anti-biofilm properties can be achieved by adding low quantities of BAG into the resin system, which offers promising abilities to mineralize as well as prevent caries without sacrificing biological activity.}, }
@article {pmid38786539, year = {2024}, author = {Karacic, J and Ruf, M and Herzog, J and Astasov-Frauenhoffer, M and Sahrmann, P}, title = {Effect of Dentifrice Ingredients on Volume and Vitality of a Simulated Periodontal Multispecies Biofilm.}, journal = {Dentistry journal}, volume = {12}, number = {5}, pages = {}, pmid = {38786539}, issn = {2304-6767}, abstract = {The aim of this in vitro study was to investigate the effect of different toothpaste ingredients on biofilm volume and vitality in an established non-contact biofilm removal model. A multi-species biofilm comprising Porphyromonas gingivalis, Streptococcus sanguinis, and Fusobacterium nucleatum was grown on protein-coated titanium disks. Six disks per group were exposed to 4 seconds non-contact brushing using a sonic toothbrush. Four groups assessed slurries containing different ingredients, i.e., dexpanthenol (DP), peppermint oil (PO), cocamidopropyl betaine (CB), and sodium hydroxide (NaOH), one positive control group with the slurry of a toothpaste (POS), and a negative control group with physiological saline (NEG). Biofilm volume and vitality were measured using live-dead staining and confocal laser scanning microscopy. Statistical analysis comprised descriptive statistics and inter-group differences. In the test groups, lowest vitality and volume were found for CB (50.2 ± 11.9%) and PO (3.6 × 10[5] ± 1.8 × 10[5] µm[3]), respectively. Significant differences regarding biofilm vitality were found comparing CB and PO (p = 0.033), CB and NEG (p = 0.014), NaOH and NEG (p = 0.033), and POS and NEG (p = 0.037). However, no significant inter-group differences for biofilm volume were observed. These findings suggest that CB as a toothpaste ingredient had a considerable impact on biofilm vitality even in a non-contact brushing setting, while no considerable impact on biofilm volume was found.}, }
@article {pmid38786175, year = {2024}, author = {Silva, A and Silva, V and Gomes, JP and Coelho, A and Batista, R and Saraiva, C and Esteves, A and Martins, &#xc2; and Contente, D and Diaz-Formoso, L and Cintas, LM and Igrejas, G and Borges, V and Poeta, P}, title = {Listeria monocytogenes from Food Products and Food Associated Environments: Antimicrobial Resistance, Genetic Clustering and Biofilm Insights.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {5}, pages = {}, pmid = {38786175}, issn = {2079-6382}, abstract = {Listeria monocytogenes, a foodborne pathogen, exhibits high adaptability to adverse environmental conditions and is common in the food industry, especially in ready-to-eat foods. L. monocytogenes strains pose food safety challenges due to their ability to form biofilms, increased resistance to disinfectants, and long-term persistence in the environment. The aim of this study was to evaluate the presence and genetic diversity of L. monocytogenes in food and related environmental products collected from 2014 to 2022 and assess antibiotic susceptibility and biofilm formation abilities. L. monocytogenes was identified in 13 out of the 227 (6%) of samples, 7 from food products (meat preparation, cheeses, and raw milk) and 6 from food-processing environments (slaughterhouse-floor and catering establishments). All isolates exhibited high biofilm-forming capacity and antibiotic susceptibility testing showed resistance to several classes of antibiotics, especially trimethoprim-sulfamethoxazole and erythromycin. Genotyping and core-genome clustering identified eight sequence types and a cluster of three very closely related ST3 isolates (all from food), suggesting a common contamination source. Whole-genome sequencing (WGS) analysis revealed resistance genes conferring resistance to fosfomycin (fosX), lincosamides (lin), fluoroquinolones (norB), and tetracycline (tetM). In addition, the qacJ gene was also detected, conferring resistance to disinfecting agents and antiseptics. Virulence gene profiling revealed the presence of 92 associated genes associated with pathogenicity, adherence, and persistence. These findings underscore the presence of L. monocytogenes strains in food products and food-associated environments, demonstrating a high virulence of these strains associated with resistance genes to antibiotics, but also to disinfectants and antiseptics. Moreover, they emphasize the need for continuous surveillance, effective risk assessment, and rigorous control measures to minimize the public health risks associated to severe infections, particularly listeriosis outbreaks. A better understanding of the complex dynamics of pathogens in food products and their associated environments can help improve overall food safety and develop more effective strategies to prevent severe health consequences and economic losses.}, }
@article {pmid38786162, year = {2024}, author = {Lee, J and Song, H and Kim, K}, title = {Inhibition of Candida albicans Biofilm Formation and Attenuation of Its Virulence by Liriope muscari.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {5}, pages = {}, pmid = {38786162}, issn = {2079-6382}, support = {GRRC-KyungHee2020(B04)//GRRC Program of Gyeonggi province/ ; 2021R1A6A3A13046056//National Research Foundation of Korea/ ; }, abstract = {(1) Background: Although Candida albicans accounts for the majority of fungal infections, therapeutic options are limited and require alternative antifungal agents with new targets; (2) Methods: A biofilm formation assay with RPMI1640 medium was performed with Liriope muscari extract. A combination antifungal assay, dimorphic transition assay, and adhesion assay were performed under the biofilm formation condition to determine the anti-biofilm formation effect. qRT-PCR analysis was accomplished to confirm changes in gene expression; (3) Results: L. muscari extract significantly reduces biofilm formation by 51.65% at 1.56 μg/mL use and therefore increases susceptibility to miconazole. L. muscari extract also inhibited the dimorphic transition of Candida; nearly 50% of the transition was inhibited when 1.56 μg/mL of the extract was treated. The extract of L. muscari inhibited the expression of genes related to hyphal development and extracellular matrix of 34.4% and 36.0%, respectively, as well as genes within the Ras1-cAMP-PKA, Cph2-Tec1, and MAP kinase signaling pathways of 25.58%, 7.1% and 15.8%, respectively, at 1.56 μg/mL of L. muscari extract treatment; (4) Conclusions: L. muscari extract significantly reduced Candida biofilm formation, which lead to induced antifungal susceptibility to miconazole. It suggests that L. muscari extract is a promising anti-biofilm candidate of Candida albicans since the biofilm formation of Candida albicans is an excellent target for candidiasis regulation.}, }
@article {pmid38783285, year = {2024}, author = {Xu, L and Wang, W and Zhang, X and Ma, K and Wang, H and Xue, T}, title = {Role of LsrR in the regulation of biofilm formation in mammary pathogenic Escherichia coli.}, journal = {BMC veterinary research}, volume = {20}, number = {1}, pages = {220}, pmid = {38783285}, issn = {1746-6148}, support = {32270194//National Natural Science Foundation of China/ ; }, mesh = {*Biofilms/growth &amp; development ; Animals ; *Escherichia coli Proteins/genetics/metabolism ; *Escherichia coli/physiology/genetics ; Cattle ; Female ; *Escherichia coli Infections/veterinary/microbiology ; *Mastitis, Bovine/microbiology ; *Gene Expression Regulation, Bacterial ; Mammary Glands, Animal/microbiology ; Repressor Proteins ; }, abstract = {BACKGROUND: Mammary Pathogenic Escherichia coli (MPEC) is an important pathogen that can escape the attack of the host immune system through biofilm formation and proliferate in the mammary gland continuously, resulting in mastitis in cows and causing enormous economic losses. As an effector of AI-2 quorum sensing, LsrR extensively affects the expression levels of hundreds of genes related to multiple biological processes in model E. coli strain. However, the regulatory role of LsrR in MPEC and whether it is involved in pathogenesis has been seldom reported.<br><br>RESULTS: In this study, the function of LsrR in strain MPEC5, obtained from a milk sample in dairy cows with mastitis, was investigated by performing high-throughput sequencing (RNA-seq) assays. The results revealed that LsrR down-regulated the transcript levels of fimAICDFGH (encoding Type 1 pili), which have been reported to be associated with biofilm formation process. Biofilm assays confirmed that deletion of lsrR resulted in a significant increase in biofilm formation in vitro. In addition, electrophoretic mobility shift assay (EMSA) provided evidence that LsrR protein could directly bind to the promoter regions of fimAICDFGH in a dose-dependent manner.<br><br>CONCLUSIONS: These results indicate that LsrR protein inhibits the biofilm formation ability of MPEC5 by directly binding to the fimAICDFGH promoter region. This study presents a novel clue for further exploration of the prevention and treatment of MPEC.}, }
@article {pmid38782213, year = {2024}, author = {Samreen,  and Ahmad, I and Khan, SA and Naseer, A and Nazir, A}, title = {Green synthesized silver nanoparticles from Phoenix dactylifera synergistically interact with bioactive extract of Punica granatum against bacterial virulence and biofilm development.}, journal = {Microbial pathogenesis}, volume = {192}, number = {}, pages = {106708}, doi = {10.1016/j.micpath.2024.106708}, pmid = {38782213}, issn = {1096-1208}, mesh = {*Silver/pharmacology/chemistry/metabolism ; *Plant Extracts/pharmacology/chemistry ; *Metal Nanoparticles/chemistry ; *Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Microbial Sensitivity Tests ; *Pseudomonas aeruginosa/drug effects ; Animals ; *Drug Synergism ; *Phoeniceae/chemistry ; Virulence/drug effects ; *Pomegranate/chemistry ; Caenorhabditis elegans/drug effects ; Green Chemistry Technology ; X-Ray Diffraction ; Virulence Factors/metabolism ; Spectroscopy, Fourier Transform Infrared ; Fruit/chemistry/microbiology ; }, abstract = {The global rise of antibiotic resistance poses a substantial risk to mankind, underscoring the necessity for alternative antimicrobial options. Developing novel drugs has become challenging in matching the pace at which microbial resistance is evolving. Recently, nanotechnology, coupled with natural compounds, has emerged as a promising solution to combat multidrug-resistant bacteria. In the present study, silver nanoparticles were green-synthesized using aqueous extract of Phoenix dactylifera (variety Ajwa) fruits and characterized by UV-vis spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM) coupled with Energy dispersive X-ray analysis (EDX), Transmission electron microscopy (TEM) and Thermogravimetric-differential thermal analysis (TGA-DTA). The in-vitro synergy of green synthesized P. dactylifera silver nanoparticle (PD-AgNPs) with selected antibiotics and bioactive extract of Punica granatum, i.e., ethyl acetate fraction (PGEF), was investigated using checkerboard assays. The most effective synergistic combination was evaluated against the QS-regulated virulence factors production and biofilm of Pseudomonas aeruginosa PAO1 by spectroscopic assays and electron microscopy. In-vivo anti-infective efficacy was examined in Caenorhabditis elegans N2 worms. PD-AgNPs were characterized as spherical in shape with an average diameter of 28.9 nm. FTIR analysis revealed the presence of functional groups responsible for the decrease and stabilization of PD-AgNPs. The signals produced by TGA-DTA analysis indicated the generation of thermally stable and pure crystallite AgNPs. Key phytocompounds detected in bioactive fractions include gulonic acid, dihydrocaffeic acid 3-O-glucuronide, and various fatty acids. The MIC of PD-AgNPs and PGEF ranged from 32 to 128 μg/mL and 250-500 μg/mL, respectively, against test bacterial strains. In-vitro, PD-AgNPs showed additive interaction with selected antibiotics (FICI 0.625-0.75) and synergy with PGEF (FICI 0.25-0.375). This combination inhibited virulence factors by up to 75 % and biofilm formation by 84.87 % in P. aeruginosa PAO1. Infected C. elegans worms with P. aeruginosa PAO1 had a 92.55 % survival rate when treated with PD-AgNPs and PGEF. The combination also reduced the reactive oxygen species (ROS) level in C. elegans N2 compared to the untreated control. Overall, these findings highlight that biosynthesized PD-AgNPs and bioactive P. granatum extract may be used as a potential therapeutic formulation against MDR bacteria.}, }
@article {pmid38781415, year = {2024}, author = {Gottenbos, B and Suntjens, W and Hötzl, S}, title = {In Vitro Biofilm Removal From Human Enamel Using a Philips® Sonicare® Power Flosser.}, journal = {Compendium of continuing education in dentistry (Jamesburg, N.J. : 1995)}, volume = {45}, number = {Suppl 1}, pages = {21}, pmid = {38781415}, issn = {2158-1797}, mesh = {*Biofilms ; Humans ; *Dental Enamel/microbiology ; *Microscopy, Confocal ; In Vitro Techniques ; *Dental Devices, Home Care ; *Microscopy, Electron, Scanning ; *Tomography, Optical Coherence ; Saliva/microbiology ; }, abstract = {The objective of this in vitro study was to quantify the removal of dental biofilm from human enamel surfaces after treatment with the Philips® Sonicare® Power Flosser. Dental biofilms were grown from pooled human saliva on human enamel disks for 4 days, according to an established academic model.* The biofilms (n = 6) were treated with the Philips Sonicare Power Flosser for 3 seconds using the Quad Stream nozzle. To quantify the number of bacteria before treatment, the biofilm volume was measured using optical coherence tomography (OCT) and the bacterial cell density was determined from untreated control samples (n = 6) using confocal laser scanning microscopy (CLSM). After treatment the number of remaining bacteria were counted using CLSM. Additionally, scanning electron microscope (SEM) images were recorded. While before treatment 0.2-mm thick dense biofilms were present, after treatment only scattered groups of bacteria remained (Figure 1 through Figure 4). Quantitative analysis showed 99.96% removal for the Quad Stream nozzle. The Philips Sonicare Power Flosser oral irrigator with Quad Stream nozzle removed over 99.9% of the bacteria in this established laboratory model of dental biofilm.}, }
@article {pmid38781414, year = {2024}, author = {Gottenbos, B and Balakrishnan, A and Mirza, F}, title = {In Vitro Comparison of the Area of Biofilm Removal by the Quad Stream Nozzle Versus a Traditional Oral Irrigator Standard Nozzle.}, journal = {Compendium of continuing education in dentistry (Jamesburg, N.J. : 1995)}, volume = {45}, number = {Suppl 1}, pages = {20}, pmid = {38781414}, issn = {2158-1797}, mesh = {*Biofilms ; Humans ; *Therapeutic Irrigation/instrumentation/methods ; In Vitro Techniques ; Equipment Design ; }, abstract = {The objective of this in vitro study was to compare the area of oral biofilm removal by the Philips Sonicare Quad Stream (PSQS) nozzle (used on a Philips® Sonicare® Power Flosser) and a traditional oral irrigator with a standard nozzle (TOIS) when used per the directions for use (DFU) instructions for both devices.}, }
@article {pmid38781413, year = {2024}, author = {Gottenbos, B and Balakrishnan, A and van de Kamp-Peeters, L and Keijser, B}, title = {Power Flossing Removes Biofilm From Model Periodontal Pockets In Vitro and Shifts the Microbiome During Biofilm Regrowth.}, journal = {Compendium of continuing education in dentistry (Jamesburg, N.J. : 1995)}, volume = {45}, number = {Suppl 1}, pages = {18-19}, pmid = {38781413}, issn = {2158-1797}, mesh = {*Biofilms ; Humans ; *Microbiota ; *Periodontal Pocket/microbiology ; *Dental Devices, Home Care ; In Vitro Techniques ; }, abstract = {The Philips® Sonicare® Power Flosser (PSPF) is highly effective in reducing gum disease. Next to effective supragingival cleaning, this may be partially driven by subgingival cleaning. This in vitro study aimed to assess the effectiveness of the PSPF in removing biofilm from a model periodontal pocket up to 6 mm deep and to investigate the taxonomic composition of biofilm regrown after use of the PSPF.}, }
@article {pmid38779563, year = {2024}, author = {Slobodianyk-Kolomoiets, M and Khlebas, S and Mazur, I and Rudnieva, K and Potochilova, V and Iungin, O and Kamyshnyi, O and Kamyshna, I and Potters, G and Spiers, AJ and Moshynets, O}, title = {Extracellular host DNA contributes to pathogenic biofilm formation during periodontitis.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1374817}, pmid = {38779563}, issn = {2235-2988}, mesh = {*Biofilms/growth &amp; development ; Humans ; *Periodontitis/microbiology ; Microscopy, Confocal ; DNA ; In Situ Hybridization, Fluorescence ; Bacteria/genetics ; DNA, Bacterial/genetics ; Inflammasomes/metabolism ; Extracellular Polymeric Substance Matrix/metabolism ; Gingiva/microbiology ; Chronic Periodontitis/microbiology/immunology ; }, abstract = {INTRODUCTION: Periodontal diseases are known to be associated with polymicrobial biofilms and inflammasome activation. A deeper understanding of the subgingival cytological (micro) landscape, the role of extracellular DNA (eDNA) during periodontitis, and contribution of the host immune eDNA to inflammasome persistence, may improve our understanding of the mechanisms underlaying severe forms of periodontitis.<br><br>METHODS: In this work, subgingival biolfilms developing on biologically neutral polyethylene terephthalate films placed in gingival cavities of patients with chronic periodontitis were investigated by confocal laser scanning microscopy (CLSM). This allowed examination of realistic cytological landscapes and visualization of extracellular polymeric substances (EPS) including amyloids, total proteins, carbohydrates and eDNA, as well as comparison with several single-strain in vitro model biofilms produced by oral pathogens such as Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus gordonii, S. sanguinis and S. mitis. Fluorescence in situ hybridization (FISH) analysis was also used to identify eDNA derived from eubacteria, streptococci and members of the Bacteroides-Porphyromonas-Prevotella (BPP) group associated with periodontitis.<br><br>RESULTS: Analysis of subgingival biofilm EPS revealed low levels of amyloids and high levels of eDNA which appears to be the main matrix component. However, bacterial eDNA contributed less than a third of the total eDNA observed, suggesting that host-derived eDNA released in neutrophil extracellular traps may be of more importance in the development of biofilms causing periodontitis.<br><br>DISCUSSION: eDNA derived from host immunocompetent cells activated at the onset of periodontitis may therefore be a major driver of bacterial persistence and pathogenesis.}, }
@article {pmid38779027, year = {2024}, author = {Wongsariya, K and Lapirattanakul, J and Chewchinda, S and Kanchanadumkerng, P}, title = {Anti-oral streptococci and anti-biofilm properties of Etlingera pavieana essential oil and its bioactive compounds proposed for an alternative herbal mouthwash.}, journal = {Heliyon}, volume = {10}, number = {10}, pages = {e31136}, pmid = {38779027}, issn = {2405-8440}, abstract = {Oral streptococci are the major group of bacteria in the oral cavity. Some of their species cause oral diseases that may lead to tooth loss and quality-of-life reduction, such as dental caries. One of prevention techniques to promote oral health is rinsing mouthwash after toothbrushing. This study aimed to determine the potential uses of local food, also remedy, plant in Thailand called Reaw-Horm or Etlingera pavieana for alternative herbal mouthwash. The essential oil from E. pavieana rhizome (Eo) is used for anti-streptococci including Streptococcus mutans and Streptococcus sobrinus and anti-biofilm activities. The main components of Eo are methyl chavicol (MC) and trans-anethole (TA). The disk diffusion method showed the inhibition zone of Eo in a dose-dependent manner. The minimum inhibitory concentration (MIC) of Eo and TA was >1.6 % v/v, and 0.4 % v/v of MC. Regarding anti-biofilm activities, MC showed nearly equal anti-biofilm formation of S. mutans and S. sobrinus, whereas Eo and TA acted toward S. sobrinus more than S. mutans biofilm. Sub-MIC killing effects on cells under biofilm were observed in Eo and MC. Therefore, MC was recommended as an active compound for anti-streptococci activities. Biocompatibility of Eo and MC were shown to be safe for epidermal cell lines. Herbal mouthwashes containing Eo were developed and had antioxidant and antimicrobial actions with established for 3 months. This study provides in vitro support on the use of herbal mouthwash with antioxidant and antimicrobial activities for dental caries prevention and well-being of individuals.}, }
@article {pmid38778618, year = {2024}, author = {AlMatar, M and Var, I and Sağlam, S and Albarri, O}, title = {The Effectiveness of LISTEXTM P100 in Reducing the Biofilm of Listeria spp. on Steel, Plastic, and Galvanised Surfaces.}, journal = {Current pharmaceutical biotechnology}, volume = {}, number = {}, pages = {}, doi = {10.2174/0113892010299925240507063431}, pmid = {38778618}, issn = {1873-4316}, abstract = {BACKGROUND: Eliminating and managing L. monocytogenes, L. welshimeri, and L. ivanovii biofilms is a significant problem for food safety, as listeriosis is among the worst foodborne illnesses.<br><br>METHOD: The Listex P100 bacteriophage's bactericidal and inhibitory properties have been investigated in relation to varying strains of vegetative cells and biofilms of L. monocytogenes, L. welshimeri, and L. ivanovii.<br><br>RESULTS: The phage concentrations of 109 and 1010 PFU/ml showed strong antibacterial activity against L. monocytogenes, L. welshimeri, and L. ivanovii at both 10&#xb0;C and 30&#xb0;C (P<0.05). In 96- well microplate experiments, bacteriophage treatment inhibited biofilm development and reduced biofilm by up to 57.6% (P &#x2264; 0.05). When compared to controls, Listex P100 bacteriophage significantly reduced the populations of L. monocytogenes, L. welshimeri, and L. ivanovii biofilms on the surfaces of galvanised, stainless steel, and plastic surfaces where holes were produced and the structure of Listeria spp. was disturbed.<br><br>CONCLUSION: This study clearly demonstrated that L. monocytogenes, L. welshimeri, and L. ivanovii biofilms on galvanised, stainless steel, and plastic surfaces might be removed by using Listex P100 bacteriophage.}, }
@article {pmid38775905, year = {2024}, author = {Elghali, F and Ibrahim, I and Guesmi, M and Frikha, F and Mnif, S}, title = {Unveiling the impact of selected essential oils on MRSA strain ATCC 33591: antibacterial efficiency, biofilm disruption, and staphyloxanthin inhibition.}, journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]}, volume = {55}, number = {3}, pages = {2057-2069}, pmid = {38775905}, issn = {1678-4405}, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology ; *Methicillin-Resistant Staphylococcus aureus/drug effects ; *Microbial Sensitivity Tests ; *Oils, Volatile/pharmacology ; *Xanthophylls/pharmacology ; *Plant Oils/pharmacology/chemistry ; Melaleuca/chemistry ; Mentha piperita/chemistry ; Pelargonium/chemistry ; Geranium/chemistry ; Citrus/chemistry ; }, abstract = {This work aimed to evaluate the effects of 4 selected essential oils on planktonic cells and microbial biofilms of the Staphylococcus aureus strain (MRSA ATCC 33591). The antibacterial activities of the four essential oils Geranium (Pelargonium graveolens), PgEO, Tea Tree (Melaleuca alternifolia) MaEO, Lemon peel (Citrus limon) ClEO and Peppermint (Mentha piperita) MpEO had MICs ranging from 1.56 to 12.5 µl/ml. The evaluation of the antibiofilm activities of the 4 EOs revealed that they had antiadhesive activities against S. aureus MRSA biofilms; the activity reached 60% (the EO of MpEO peppermint at a concentration of 3.12 µl/ml), and the eradication activity was 80% (the EO of PgEO and MpEO at 3.12 µl/ml). The antibiofilm activity of S. aureus has been explained by the binding of several essential oil bioactive molecules to the SarA protein, the main target protein involved in biofilm formation. The synthesis of the virulence factor staphyloxanthin by S. aureus MRSA ATCC 33591 was significantly inhibited in the presence of PgEO at a concentration of MIC/2. This inhibition was explained by the binding of the main PgEO molecules (β-citronellol and geraniol) to the CrTM protein involved in the staphyloxanthin synthesis pathway. There is evidence that these essential oils could be used as potential anti-virulents to control Staphylococcus biofilm formation.}, }
@article {pmid38772746, year = {2024}, author = {Salvado, MG and André, LSP and Pereira, RFA and Pinheiro, FR and Barbosa, BDC and Scaffo, JC and Pereira, AJ and Arakaki, DG and Xing, H and de Oliveira, KMP and de Andrade Dos Santos, JV and Sachs, D and Aguiar-Alves, F and Conda-Sheridan, M and Penna, B}, title = {Evaluating the antimicrobial and anti-biofilm activity of three synthetic antimicrobial Citropin analogs and their ability to fight against Staphylococcus aureus and Staphylococcus pseudintermedius.}, journal = {Journal of applied microbiology}, volume = {135}, number = {6}, pages = {}, doi = {10.1093/jambio/lxae127}, pmid = {38772746}, issn = {1365-2672}, support = {E26/211.554/2019//Funda&#xe7;&#xe3;o Carlos Chagas Filho de Amparo &#xe0; Pesquisa do Estado do Rio de Janeiro/ ; 406&#xa0;057/2016-8//Conselho Nacional de Desenvolvimento Cient&#xed;fico e Tecnol&#xf3;gico/ ; 001//Coordena&#xe7;&#xe3;o de Aperfei&#xe7;oamento de Pessoal de N&#xed;vel Superior/ ; }, mesh = {*Biofilms/drug effects ; *Microbial Sensitivity Tests ; *Staphylococcus aureus/drug effects ; Humans ; *Anti-Bacterial Agents/pharmacology ; *Staphylococcus/drug effects ; Antimicrobial Peptides/pharmacology/chemistry ; Erythrocytes/drug effects ; Keratinocytes/drug effects ; }, abstract = {AIMS: We developed three new analogs of the antimicrobial peptide (AMP) Citropin 1.1: DAN-1-13, AJP-1-1, and HHX-2-28, and tested their potential antimicrobial and antibiofilm activities against Staphylococcus aureus and S. pseudintermedius. Potential cytotoxic or hemolytic effects were determined using cultured human keratinocytes and erythrocytes to determine their safety.<br><br>METHODS AND RESULTS: To assess the antimicrobial activity of each compound, minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) were determined against methicillin-resistant and methicillin-susceptible strains of S. aureus and S. pseudintermedius. Activity against newly formed and mature biofilms was determined in two clinical isolates using spectrophotometry and scanning electron microscopy (SEM). All three compounds exhibited antimicrobial and bactericidal activity against all studied S. aureus and S. pseudintermedius strains, with MICs ranging from 4-32&#xa0;&#x3bc;g ml-1 and MBCs ranging from 8-128&#xa0;&#x3bc;g ml-1. Subinhibitory concentrations of all compounds also showed ant-biofilm activity in the two tested isolates. All compounds exhibited limited cytotoxic and hemolytic activity.<br><br>CONCLUSIONS: Novel analogs of Citropin 1.1 exhibit antimicrobial and bactericidal activities against S. aureus and S. pseudintermedius isolates and inhibit the biofilm formation of these bacteria.}, }
@article {pmid38769535, year = {2024}, author = {Enrique, CG and Medel-Plaza, M and Correa, JJA and Sarnago, H and Acero, J and Burdio, JM and Lucía, &#xd3; and Esteban, J and Gómez-Barrena, E}, title = {Biofilm on total joint replacement materials can be reduced through electromagnetic induction heating using a portable device.}, journal = {Journal of orthopaedic surgery and research}, volume = {19}, number = {1}, pages = {304}, pmid = {38769535}, issn = {1749-799X}, mesh = {*Biofilms/drug effects ; *Titanium ; *Alloys ; *Disinfection/methods ; *Escherichia coli/growth &amp; development ; *Staphylococcus aureus/drug effects ; *Prosthesis-Related Infections/prevention &amp; control/microbiology ; Staphylococcus epidermidis/drug effects ; Joint Prosthesis/microbiology ; Arthroplasty, Replacement/instrumentation/methods ; Heating/instrumentation/methods ; Humans ; Electromagnetic Phenomena ; Vitallium ; }, abstract = {BACKGROUND: Periprosthetic joint infection is a serious complication following joint replacement. The development of bacterial biofilms bestows antibiotic resistance and restricts treatment via implant retention surgery. Electromagnetic induction heating is a novel technique for antibacterial treatment of metallic surfaces that has demonstrated in-vitro efficacy. Previous studies have always employed stationary, non-portable devices. This study aims to assess the in-vitro efficacy of induction-heating disinfection of metallic surfaces using a new Portable Disinfection System based on Induction Heating.<br><br>METHODS: Mature biofilms of three bacterial species: S. epidermidis ATCC 35,984, S. aureus ATCC 25,923, E. coli ATCC 25,922, were grown on 18&#x2009;&#xd7;&#x2009;2&#xa0;mm cylindrical coupons of Titanium-Aluminium-Vanadium (Ti6Al4V) or Cobalt-chromium-molybdenum (CoCrMo) alloys. Study intervention was induction-heating of the coupon surface up to 70&#xba;C for 210s, performed using the Portable Disinfection System (PDSIH). Temperature was monitored using thermographic imaging. For each bacterial strain and each metallic alloy, experiments and controls were conducted in triplicate. Bacterial load was quantified through scraping and drop plate techniques. Data were evaluated using non-parametric Mann-Whitney U test for 2 group comparison. Statistical significance was fixed at p&#x2009;&#x2264;&#x2009;0.05.<br><br>RESULTS: All bacterial strains showed a statistically significant reduction of CFU per surface area in both materials. Bacterial load reduction amounted to 0.507 and 0.602 Log10 CFU/mL for S. aureus on Ti6Al4V and CoCrMo respectively, 5.937 and 3.500 Log10 CFU/mL for E. coli, and 1.222 and 0.372 Log10 CFU/mL for S. epidermidis.<br><br>CONCLUSIONS: Electromagnetic induction heating using PDSIH is efficacious to reduce mature biofilms of S aureus, E coli and S epidermidis growing on metallic surfaces of Ti6Al4V and CoCrMo alloys.}, }
@article {pmid38767749, year = {2024}, author = {Lima, LS and Müller, TN and Ansiliero, R and Schuster, MB and Silva, BL and Jaskulski, IB and da Silva, WP and Moroni, LS}, title = {Biofilm formation by Listeria monocytogenes from the meat processing industry environment and the use of different combinations of detergents, sanitizers, and UV-A radiation to control this microorganism in planktonic and sessile forms.}, journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]}, volume = {55}, number = {3}, pages = {2483-2499}, pmid = {38767749}, issn = {1678-4405}, mesh = {*Biofilms/drug effects/radiation effects/growth &amp; development ; *Listeria monocytogenes/drug effects/radiation effects/growth &amp; development/physiology ; *Ultraviolet Rays ; *Detergents/pharmacology ; *Disinfectants/pharmacology ; Microbial Sensitivity Tests ; Food-Processing Industry ; Stainless Steel ; Food Microbiology ; Peracetic Acid/pharmacology ; }, abstract = {This study aimed to evaluate the ability of biofilm formation by L. monocytogenes from the meat processing industry environment, as well as the use of different combinations of detergents, sanitizers, and UV-A radiation in the control of this microorganism in the planktonic and sessile forms. Four L. monocytogenes isolates were evaluated and showed moderate ability to form biofilm, as well as carried genes related to biofilm production (agrB, agrD, prfA, actA, cheA, cheY, flaA, sigB), and genes related to tolerance to sanitizers (lde and qacH). The biofilm-forming isolates of L. monocytogenes were susceptible to quaternary ammonium compound (QAC) and peracetic acid (PA) in planktonic form, with minimum inhibitory concentrations of 125 and 75 ppm, respectively, for contact times of 10 and 5 min. These concentrations are lower than those recommended by the manufacturers, which are at least 200 and 300 ppm for QAC and PA, respectively. Biofilms of L. monocytogenes formed from a pool of isolates on stainless steel and polyurethane coupons were subjected to 14 treatments involving acid and enzymatic detergents, QAC and PA sanitizers, and UV-A radiation at varying concentrations and contact times. All treatments reduced L. monocytogenes counts in the biofilm, indicating that the tested detergents, sanitizers, and UV-A radiation exhibited antimicrobial activity against biofilms on both surface types. Notably, the biofilm formed on polyurethane showed greater tolerance to the evaluated compounds than the biofilm on stainless steel, likely due to the material's surface facilitating faster microbial colonization and the development of a more complex structure, as observed by scanning electron microscopy. Listeria monocytogenes isolates from the meat processing industry carry genes associated with biofilm production and can form biofilms on both stainless steel and polyurethane surfaces, which may contribute to their persistence within meat processing lines. Despite carrying sanitizer tolerance genes, QAC and PA effectively controlled these microorganisms in their planktonic form. However, combinations of detergent (AC and ENZ) with sanitizers (QAC and PA) at minimum concentrations of 125 ppm and 300 ppm, respectively, were the most effective.}, }
@article {pmid38766297, year = {2024}, author = {Ferreira, I and de Campos, MR and Sahm, BD and da Costa Valente, ML and Marcondes Agnelli, JA and Dos Reis, AC}, title = {Influence of post-processing on the adhesion of dual-species biofilm on polylactic acid obtained by additive manufacturing.}, journal = {The Saudi dental journal}, volume = {36}, number = {5}, pages = {733-739}, pmid = {38766297}, issn = {1013-9052}, abstract = {INTRODUCTION: Post-processing (PP) is performed to improve the surface, which can favor microbial adhesion and consequent pathological manifestations that impair the indication of polylactic acid (PLA) obtained by fused filament fabrication (FFF) for biomedical applications. This aims to evaluate the influence of chemical, thermal, and mechanical PP on the adhesion of Streptococcus mutants and Candida albicans, roughness, and wettability of the PLA obtained by FFF with and without thermal aging.<br><br>METHODS: The specimens were designed in the 3D modeling program and printed. The chemical PP was performed by immersion in chloroform, the thermal by the annealing method, and the mechanical by polishing. Thermal aging was performed by alternating the temperature from 5&#xa0;&#xb0;C to 55&#xa0;&#xb0;C with 5000 cycles. Colony-forming unit (CFU/mL) counting was performed on dual-species biofilm of C. albicans and S. mutans. Roughness was analyzed by rugosimeter and wettability by the sessile drop technique. Data were verified for normality using the Shapiro-Wilk test, two-way ANOVA (&#x3b1;&#xa0;=&#xa0;0.05) applied for CFU and wettability, and Kruskal-Wallis (&#x3b1;&#xa0;=&#xa0;0.05) for roughness.<br><br>RESULTS: Chemical, thermal, and mechanical PP methods showed no influence on CFU/mL of C. albicans (p&#xa0;=&#xa0;0.296) and S. mutans (p&#xa0;=&#xa0;0.055). Thermal aging did not influence microbial adhesion. Chemical PP had lower roughness, which had increased after aging. Wettability of the mechanical PP was lower.<br><br>CONCLUSIONS: Post-processing techniques, do not present an influence on the adhesion of S. mutans and C. albicans in PLA obtained by FFF, chemical PP reduced roughness, and mechanical reduced wettability. Thermal aging did not alter the microbial adhesion and altered the roughness and wettability.}, }
@article {pmid38763690, year = {2024}, author = {Ashrafudoulla, M and Yun, H and Ashikur Rahman, M and Jung, SJ and Jie-Won Ha, A and Anamul Hasan Chowdhury, M and Shaila, S and Akter, S and Park, SH and Ha, SD}, title = {Prophylactic efficacy of baicalin and carvacrol against Salmonella Typhimurium biofilm on food and food contact surfaces.}, journal = {Food research international (Ottawa, Ont.)}, volume = {187}, number = {}, pages = {114458}, doi = {10.1016/j.foodres.2024.114458}, pmid = {38763690}, issn = {1873-7145}, mesh = {*Biofilms/drug effects ; *Cymenes/pharmacology ; *Salmonella typhimurium/drug effects ; *Flavonoids/pharmacology ; *Microbial Sensitivity Tests ; *Food Microbiology ; *Anti-Bacterial Agents/pharmacology ; Animals ; *Chickens ; Quorum Sensing/drug effects ; Meat/microbiology ; Monoterpenes/pharmacology ; Microscopy, Electron, Scanning ; }, abstract = {This study examines the antimicrobial and antibiofilm effectiveness of baicalin and carvacrol against Salmonella enterica ser. Typhimurium on food contact surfaces and chicken meat. The minimum inhibitory concentrations (MIC) for baicalin and carvacrol were found to be 100 μg/mL and 200 μg/mL, respectively, which aligns with findings from previous studies. The compounds exhibited a concentration-dependent decrease in microbial populations and biofilm formation. When used together, they displayed a remarkable synergistic effect, greatly augmenting their antibacterial activity. The assessment of food quality demonstrated that these treatments have no negative impact on the sensory characteristics of chicken meat. The impact of the structure on biofilms was observed through the use of Field Emission Scanning Electron Microscopy (FE-SEM) and Confocal Laser Scanning Microscopy (CLSM), revealing disrupted biofilm architectures and decreased cell viability. Crucially, RT-PCR analysis revealed a marked downregulation of quorum sensing (luxS), virulence (hilA), and stress response (rpoS) genes, highlighting the multifaceted antimicrobial mechanism of action. This gene-specific suppression suggests a targeted disruption of bacterial communication and virulence pathways, offering insight into the comprehensive antibiofilm strategy. This provides further insight into the molecular mechanisms that contribute to their antibiofilm effects.}, }
@article {pmid38762620, year = {2024}, author = {Upmanyu, K and Kumar, R and Rizwanul Haque, QM and Singh, R}, title = {Exploring the evolutionary and pathogenic role of Acinetobacter baumannii biofilm-associated protein (Bap) through in silico structural modeling.}, journal = {Archives of microbiology}, volume = {206}, number = {6}, pages = {267}, pmid = {38762620}, issn = {1432-072X}, mesh = {*Acinetobacter baumannii/genetics/chemistry/metabolism ; *Biofilms/growth &amp; development ; *Bacterial Proteins/genetics/chemistry/metabolism ; *Phylogeny ; Humans ; Acinetobacter Infections/microbiology ; Evolution, Molecular ; Computer Simulation ; Models, Molecular ; }, abstract = {Acinetobacter species encode for extracellularly secreted Biofilm-associated protein (Bap), a multi-domain protein with variable molecular weights reaching several hundred kilodaltons. Bap is crucial for the development of multi-dimensional structures of mature biofilms. In our investigation, we analyzed 7338 sequences of A. baumannii from the NCBI database and found that Bap or Bap-like protein (BLP) was present in 6422 (87.52%) isolates. Further classification revealed that 12.12% carried Type-1 Bap, 68.44% had Type-2, 6.91% had Type-3, 0.05% had Type-6 or SDF-Type, and 12.51% lacked Bap or BLP. The majority of isolates with Type-1, Type-2, and Type-3 Bap belonged to ST1, ST2, and ST25, respectively. Phylogenetic analysis suggested that Type-1 Bap is the most ancient, while Type-3 and SDF-Type have evolved recently. Studying the interaction of predicted Bap structures with human CEACAM-1 and PIgR showed that Bap with its BIg13 and BIg6 domains interact with the N-terminal domain of CEACAM-1, involving Arg[43] and Glu[40], involved in CEACAM-1 dimerization. Also, we found that recently evolved Type-3 and SDF-Type Bap showed greater interaction with CEACAM-1 and PIgR. It can be asserted that the evolution of Bap has conferred enhanced virulence characteristics to A. baumannii with increased interaction with CEACAM-1 and PIgR. Using in silico approaches, this study explores the evolutionary, physicochemical, and structural features of A. baumannii Bap and unravels its crucial role in mediating interaction with human CEACAM-1 and PIgR through detailed structure modelling. These findings advance our understanding of A. baumannii Bap and highlight its role in pathogenesis.}, }
@article {pmid38762474, year = {2024}, author = {Lutfi, LL and Shaaban, MI and Elshaer, SL}, title = {Vitamin D and vitamin K1 as novel inhibitors of biofilm in Gram-negative bacteria.}, journal = {BMC microbiology}, volume = {24}, number = {1}, pages = {173}, pmid = {38762474}, issn = {1471-2180}, mesh = {*Biofilms/drug effects/growth &amp; development ; Humans ; *Vitamin K 1/pharmacology ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; *Vitamin D/pharmacology ; *Gram-Negative Bacteria/drug effects ; Pseudomonas aeruginosa/drug effects/physiology ; Gram-Negative Bacterial Infections/microbiology/drug therapy ; Acinetobacter baumannii/drug effects/physiology/isolation &amp; purification ; Drug Resistance, Multiple, Bacterial/drug effects ; }, abstract = {BACKGROUND: The persistent surge in antimicrobial resistance represents a global disaster. The initial attachment and maturation of microbial biofilms are intimately related to antimicrobial resistance, which in turn exacerbates the challenge of eradicating bacterial infections. Consequently, there is a pressing need for novel therapies to be employed either independently or as adjuvants to diminish bacterial virulence and pathogenicity. In this context, we propose a novel approach focusing on vitamin D and vitamin K1 as potential antibiofilm agents that target Gram-negative bacteria which are hazardous to human health.<br><br>RESULTS: Out of 130 Gram-negative bacterial isolates, 117 were confirmed to be A. baumannii (21 isolates, 17.9%), K. pneumoniae (40 isolates, 34.2%) and P. aeruginosa (56 isolates, 47.9%). The majority of the isolates were obtained from blood and wound specimens (27.4% each). Most of the isolates exhibited high resistance rates to &#x3b2;-lactams (60.7-100%), ciprofloxacin (62.5-100%), amikacin (53.6-76.2%) and gentamicin (65-71.4%). Approximately 93.2% of the isolates were biofilm producers, with 6.8% categorized as weak, 42.7% as moderate, and 50.4% as strong biofilm producers. The minimum inhibitory concentrations (MICs) of vitamin D and vitamin K1 were 625-1250&#xa0;&#xb5;g mL-1 and 2500-5000&#xa0;&#xb5;g mL-1, respectively, against A. baumannii (A5, A20 and A21), K. pneumoniae (K25, K27 and K28), and P. aeruginosa (P8, P16, P24 and P27) clinical isolates and standard strains A. baumannii (ATCC 19606 and ATCC 17978), K. pneumoniae (ATCC 51503) and P. aeruginosa PAO1 and PAO14. Both vitamins significantly decreased bacterial attachment and significantly eradicated mature biofilms developed by the selected standard and clinical Gram-negative isolates. The anti-biofilm effects of both supplements were confirmed by a notable decrease in the relative expression of the biofilm-encoding genes cusD, bssS and pelA in A. baumannii A5, K. pneumoniae K28 and P. aeruginosa P16, respectively.<br><br>CONCLUSION: This study highlights the anti-biofilm activity of vitamins D and K1 against the tested Gram-negative strains, which emphasizes the potential of these vitamins for use as adjuvant therapies to increase the efficacy of treatment for infections caused by multidrug-resistant (MDR) strains and biofilm-forming phenotypes. However, further validation through in vivo studies is needed to confirm these promising results.}, }
@article {pmid38761913, year = {2024}, author = {Zulfiqar, S and Sharif, S and Nawaz, MS and Shahzad, SA and Bashir, MM and Iqbal, T and Ur Rehman, I and Yar, M}, title = {Cu-MOF loaded chitosan based freeze-dried highly porous dressings with anti-biofilm and pro-angiogenic activities accelerated Pseudomonas aeruginosa infected wounds healing in rats.}, journal = {International journal of biological macromolecules}, volume = {271}, number = {Pt 2}, pages = {132443}, doi = {10.1016/j.ijbiomac.2024.132443}, pmid = {38761913}, issn = {1879-0003}, mesh = {Animals ; *Chitosan/chemistry/pharmacology ; *Wound Healing/drug effects ; *Metal-Organic Frameworks/chemistry/pharmacology ; Rats ; *Bandages ; *Freeze Drying ; *Pseudomonas aeruginosa/drug effects ; Porosity ; *Copper/chemistry/pharmacology ; *Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; Pseudomonas Infections/drug therapy/microbiology/therapy ; Male ; Angiogenesis Inducing Agents/pharmacology/chemistry ; Wound Infection/drug therapy/microbiology ; }, abstract = {Metal-organic frameworks (MOFs)-based therapy opens a new area for antibiotic-drug free infections treatment. In the present study, chitosan membranes (CS) loaded with two concentrations of copper-MOF 10 mg/20 ml (Cu-MOF10/CS) &amp; 20 mg/20 ml (Cu-MOF20/CS) were prepared by a simple lyophilization procedure. FTIR spectra of Cu-MOF10/CS and Cu-MOF20/CS dressings confirmed absence of any undesirable chemical changes after loading Cu-MOF. The SEM images of the synthesized materials (CS, Cu-MOF10/CS &amp; Cu-MOF20/CS) showed interconnected porous structures. Cytocompatibility of the materials was confirmed by fibroblasts cells culturing and the materials were hemocompatible, with blood clotting index <5 %. Cu-MOF20/CS showed comparatively higher effective antibacterial activity against the tested strains; E. coli (149.2 %), P. aeruginosa (165 %) S. aureus (117.8 %) and MRSA (142 %) as compared to Amikacin, CS and Cu-MOF10/CS membranes. Similarly, Cu-MOF20/CS dressing significantly eradicated the biofilms; P. aeruginosa (37 %) and MRSA (52 %) respectively. In full thickness infected wound rat model, on day 23, Cu-MOF10/CS and Cu-MOF20/CS promoted wound healing up to 87.7 % and 82 % respectively. H&amp;E staining of wounded tissues treated with Cu-MOF10/CS &amp; Cu-MOF20/CS demonstrated enhanced neovascularization and re-epithelization along-with reduced inflammation, while trichrome staining exhibited increased collagen deposition. Overall, this study declares Cu-MOFs loaded chitosan dressings a multifunctional platform for the healing of infected wounds.}, }
@article {pmid38761225, year = {2024}, author = {Goulart, TS and Hawerroth, T and da Silveira Teixeira, C and Cesca, K and Silva, RR and de Moraes, RR and Minamisako, MC and Umeda Takashima, MT and Cábia, NC and Bortoluzzi, EA and Mazzon, RR and de Almeida, J and da Fonseca Roberti Garcia, L}, title = {Assessment of multispecies biofilm growth on root canal dentin under different radiation therapy regimens.}, journal = {Clinical oral investigations}, volume = {28}, number = {6}, pages = {324}, pmid = {38761225}, issn = {1436-3771}, mesh = {*Biofilms/radiation effects ; *Dentin/microbiology/radiation effects ; Humans ; *Dental Pulp Cavity/microbiology/radiation effects ; *Candida albicans/radiation effects ; Animals ; *Enterococcus faecalis/radiation effects ; *Streptococcus mutans/radiation effects ; Cattle ; Microscopy, Electron, Scanning ; Hardness ; Microscopy, Confocal ; Radiotherapy Dosage ; }, abstract = {OBJECTIVES: To assess the growth of a multispecies biofilm on root canal dentin under different radiotherapy regimens.<br><br>MATERIALS AND METHODS: Sixty-three human root dentin cylinders were distributed into six groups. In three groups, no biofilm was formed (n&#x2009;=&#x2009;3): NoRT) non-irradiated dentin; RT55) 55&#xa0;Gy; and RT70) 70&#xa0;Gy. In the other three groups (n&#x2009;=&#x2009;18), a 21-day multispecies biofilm (Enterococcus faecalis, Streptococcus mutans, and Candida albicans) was formed in the canal: NoRT&#x2009;+&#x2009;Bio) non-irradiated&#x2009;+&#x2009;biofilm; RT55&#x2009;+&#x2009;Bio) 55&#xa0;Gy&#x2009;+&#x2009;biofilm; and RT70&#x2009;+&#x2009;Bio) 70&#xa0;Gy&#x2009;+&#x2009;biofilm. The biofilm was quantified (CFUs/mL). Biofilm microstructure was assessed under SEM. Microbial penetration into dentinal tubules was assessed under CLSM. For the biofilm biomass and dentin microhardness pre- and after biofilm growth assessments, 45 bovine dentin specimens were distributed into three groups (n&#x2009;=&#x2009;15): NoRT) non-irradiated&#x2009;+&#x2009;biofilm; RT55&#x2009;+&#x2009;Bio) 55&#xa0;Gy&#x2009;+&#x2009;biofilm; and RT70&#x2009;+&#x2009;Bio) 70&#xa0;Gy&#x2009;+&#x2009;biofilm.<br><br>RESULTS: Irradiated specimens (70&#xa0;Gy) had higher quantity of microorganisms than non-irradiated (p&#x2009;=&#x2009;.010). There was gradual increase in biofilm biomass from non-irradiated to 55&#xa0;Gy and 70&#xa0;Gy (p&#x2009;<&#x2009;.001). Irradiated specimens had greater reduction in microhardness after biofilm growth. Irradiated dentin led to the growth of a more complex and irregular biofilm. There was microbial penetration into the dentinal tubules, regardless of the radiation regimen.<br><br>CONCLUSION: Radiotherapy increased the number of microorganisms and biofilm biomass and reduced dentin microhardness. Microbial penetration into dentinal tubules was noticeable.<br><br>CLINICAL RELEVANCE: Cumulative and potentially irreversible side effects of radiotherapy affect biofilm growth on root dentin. These changes could compromise the success of endodontic treatment in oncological patients undergoing head and neck radiotherapy.}, }
@article {pmid38761198, year = {2024}, author = {Schaffler, BC and Longwell, M and Byers, B and Kreft, R and Ramot, R and Ramot, Y and Schwarzkopf, R}, title = {Nanoparticle ultrasonication outperforms conventional irrigation solutions in eradicating Staphylococcus aureus biofilm from titanium surfaces: an in vitro study.}, journal = {European journal of orthopaedic surgery &amp; traumatology : orthopedie traumatologie}, volume = {34}, number = {5}, pages = {2729-2734}, pmid = {38761198}, issn = {1432-1068}, mesh = {*Titanium ; *Biofilms/drug effects ; *Therapeutic Irrigation/methods ; *Povidone-Iodine/pharmacology/administration &amp; dosage ; Chlorhexidine/analogs &amp; derivatives/pharmacology/administration &amp; dosage ; Nanoparticles ; Methicillin-Resistant Staphylococcus aureus/drug effects ; Prosthesis-Related Infections/prevention &amp; control/microbiology ; Anti-Infective Agents, Local/pharmacology/administration &amp; dosage ; Humans ; Staphylococcus aureus/drug effects ; In Vitro Techniques ; Sonication/methods ; }, abstract = {PURPOSE: Bacterial biofilms create a challenge in the treatment of prosthetic joint infection (PJI), and failure to eradicate biofilms is often implicated in the high rates of recurrence. In this study, we aimed to compare the effectiveness of a novel nanoparticle ultrasonication technology on Staphylococcus aureus biofilm eradication compared to commonly used orthopedic irrigation solutions.<br><br>METHODS: Twenty-four sterile, titanium alloy discs were inoculated with a standardized concentration of methicillin-resistant S. aureus and cultured for seven days to allow for biofilm formation. Discs were then treated with either ultrasonicated nanoparticle therapy or irrigation with chlorhexidine gluconate, povidone-iodine or normal saline. The remaining bacteria on each surface was subsequently plated for colony-forming units of S. aureus. Bacterial eradication was reported as a decrease in CFUs relative to the control group. Mann-Whitney U tests were used to compare between groups.<br><br>RESULTS: Treatment with ultrasonicated nanoparticles resulted in a significant mean decrease in CFUs of 99.3% compared to controls (p&#x2009;<&#x2009;0.0001). Irrigation with povidone-iodine also resulted in a significant 77.5% reduction in CFUs compared to controls (p&#x2009;<&#x2009;0.0001). Comparisons between ultrasonicated nanoparticles and povidone-iodine demonstrated a significantly higher reduction in bacterial CFUs in the nanoparticle group (p&#x2009;<&#x2009;0.0001).<br><br>CONCLUSION: Ultrasonicated nanoparticle were superior to commonly used bactericidal irrigation solutions in the eradication of S. aureus from a titanium surface. Future clinical studies are warranted to evaluate this ultrsonication technology in the treatment of PJI.}, }
@article {pmid38760974, year = {2024}, author = {Ruffier d'Epenoux, L and Fayoux, E and Veziers, J and Dagnelie, MA and Khammari, A and Dréno, B and Corvec, S}, title = {Biofilm of Cutibacterium acnes: a target of different active substances.}, journal = {International journal of dermatology}, volume = {63}, number = {11}, pages = {1541-1550}, doi = {10.1111/ijd.17194}, pmid = {38760974}, issn = {1365-4632}, mesh = {*Biofilms/drug effects ; *Plant Extracts/pharmacology ; *Anti-Bacterial Agents/pharmacology ; Humans ; *Acne Vulgaris/microbiology/drug therapy ; Propionibacterium acnes/drug effects/isolation &amp; purification/physiology ; Doxycycline/pharmacology ; Clindamycin/pharmacology ; Microbial Sensitivity Tests ; Propionibacteriaceae ; }, abstract = {BACKGROUND: Acne vulgaris is a chronic inflammatory dermatosis. Cutibacterium acnes plays a crucial role in the acne pathophysiology. Recent works present evidence of C. acnes growing as a biofilm in cutaneous follicles. This development is currently considered one of the leading causes of C. acnes in vivo persistence and resistance to antimicrobials used to treat acne.<br><br>OBJECTIVE: Our objective was to evaluate the effects of various active compounds (clindamycin, erythromycin, doxycycline, and myrtle extract) on eight distinct, well-characterized strains of C. acnes following their growth in biofilm mode.<br><br>METHODS/RESULTS: Cutibacterium acnes isolates from phylotypes IA1 and IA2 produce more biofilm than other phylotypes. No antibiotic effect was observed either during the curative test or preventive test. Myrtle extract at 0.01% (w/v) showed significant efficacy on the biofilm for C. acnes strains (curative assays). Furthermore, it appear that myrtle extract and doxycycline together reduce the overall biomass of the biofilm. A significant dose-dependent effect was observed during the preventive test, greater than the one observed under curative conditions, with an important loss of activity of the myrtle extract observed from 0.001% (w/v) concentration onwards. Transmission electron microscopy showed that bacteria treated with&#xa0;myrtle extract grew biofilms much less frequently than untreated bacteria. Additionally, when the quantity of myrtle extract grew, the overall number of bacteria dropped, indicating an additional antibacterial action.<br><br>CONCLUSION: These findings support the hypothesis that the different C. acnes phylotypes have various aptitudes in forming biofilms. They also suggest that myrtle extract is a promising alternative as an anti-biofilm and antibacterial agent in fighting diseases caused by planktonic and biofilm C. acnes.}, }
@article {pmid38759549, year = {2024}, author = {Zhao, B and Yang, G and Xie, Z and Zhang, N and Xia, J and Liu, X and Wang, D and Wang, P and Tang, L}, title = {Efficient degradation of venlafaxine using intimately coupled high-active crystal facets exposed TiO2 and biodegradation system: Kinetic studies, biofilm stress behavior and transformation mechanism.}, journal = {Journal of environmental management}, volume = {360}, number = {}, pages = {121159}, doi = {10.1016/j.jenvman.2024.121159}, pmid = {38759549}, issn = {1095-8630}, mesh = {*Venlafaxine Hydrochloride ; *Biofilms/drug effects ; *Titanium/chemistry ; *Biodegradation, Environmental ; Kinetics ; Water Pollutants, Chemical/metabolism/chemistry ; Wastewater/chemistry ; Catalysis ; }, abstract = {Intimately coupled photocatalysis and biodegradation (ICPB) system is a potential wastewater treatment technology, of which TiO2-based ICPB system has been widely studied. There are many ways to improve the degradation efficiency of the ICPB process, but no crystal facet engineering method has been reported yet. In this work, a new ICPB system coated with NaF-TiO2 exposing high energy facets was designed to degrade biorecalcitrant psychotropic drug - venlafaxine (VNF). Initially, the TiO2 crystal surface was modified with NaF, resulting in the formation of NaF-TiO2 with a 14.4% increase in the exposure ratio of (001). The contribution rate of ·OH was increased by 9.5%, and the contribution rate of h[+] was increased by 33.2%. Next, NaF-TiO2 was loaded onto the surface of the sponge carrier, and then the ICPB system was constructed after about 15 days of biofilm formation. After the ICPB system was acclimated with VNF, the removal rate of COD decreased significantly (the lowest was 62.7%), but that of ammonia nitrogen remained at 50.5 ± 6.0% and the extracellular polymeric substance (EPS) secretion increased by 84.1 mg/g VSS. According to the high throughput results, at the phylum level, Proteobacteria and Chloroflexi together maintain the nitrogen removal capability and structural stability of the ICPB system. The relative abundance of Bacteroidota was significantly increased by 14.2%, suggesting that there may be some correlation between Bacteroidota and certain metabolites of the anti-depressant active ingredients. At the genus level, the Thauera (3.1%∼11.5%) is the major bacterial group that secretes EPS, protecting biofilm against external influences. Most of the changes in microorganisms are consistent with the decontamination properties and macroscopic appearance of EPS in the ICPB system. Finally, the degradation efficiency of ICPB system for VNF was investigated (92.7 ± 3.8%) and it was mostly through hydroxylation and demethylation pathways, with more small molecular products detected, providing the basis for biological assimilation of VNF. Collectively, the NaF-TiO2 based ICPB system would be lucrative for the future degradation of venlafaxine.}, }
@article {pmid38759479, year = {2024}, author = {Khan, A and Xu, L and Kijkla, P and Kumseranee, S and Punpruk, S and Gu, T}, title = {Surface roughness influence on extracellular electron microbiologically influenced corrosion of C1018 carbon steel by Desulfovibrio ferrophilus IS5 biofilm.}, journal = {Bioelectrochemistry (Amsterdam, Netherlands)}, volume = {159}, number = {}, pages = {108731}, doi = {10.1016/j.bioelechem.2024.108731}, pmid = {38759479}, issn = {1878-562X}, mesh = {*Biofilms ; Corrosion ; *Steel/chemistry ; *Surface Properties ; *Desulfovibrio/metabolism/physiology ; *Carbon/chemistry/metabolism ; Electrons ; Electron Transport ; Sulfates/metabolism/chemistry ; }, abstract = {Carbon steel microbiologically influenced corrosion (MIC) by sulfate reducing bacteria (SRB) is known to occur via extracellular electron transfer (EET). A higher biofilm sessile cell count leads to more electrons being harvested for sulfate reduction by SRB in energy production. Metal surface roughness can impact the severity of MIC by SRB because of varied biofilm attachment. C1018 carbon steel coupons (1.2 cm[2] top working surface) polished to 36 grit (4.06 μm roughness which is relatively rough) and 600 grit (0.13 μm) were incubated in enriched artificial seawater inoculated with highly corrosive Desulfovibrio ferrophilus IS5 at 28 ℃ for 7 d and 30 d. It was found that after 7 d of SRB incubation, 36 grit coupons had a 11% higher sessile cell count at (2.0 ± 0.17) × 10[8] cells/cm[2], 52% higher weight loss at 22.4 ± 5.9 mg/cm[2] (1.48 ± 0.39 mm/a uniform corrosion rate), and 18% higher maximum pit depth at 53 μm compared with 600 grit coupons. However, after 30 d, the differences diminished. Electrochemical tests with transient information supported the weight loss data trends. This work suggests that a rougher surface facilitates initial biofilm establishment but provides no long-term advantage for increased biofilm growth.}, }
@article {pmid38759403, year = {2024}, author = {Song, Z and Zhang, L and Yang, J and Ni, SQ and Peng, Y}, title = {Achieving high nitrogen and antibiotics removal efficiency by nZVI-C in partial nitritation/anammox system with a single-stage membrane-aerated biofilm reactor.}, journal = {Journal of hazardous materials}, volume = {473}, number = {}, pages = {134626}, doi = {10.1016/j.jhazmat.2024.134626}, pmid = {38759403}, issn = {1873-3336}, mesh = {*Bioreactors ; *Anti-Bacterial Agents ; *Biofilms ; *Nitrogen/metabolism ; *Iron/metabolism/chemistry ; Water Pollutants, Chemical/metabolism ; Membranes, Artificial ; Ammonia/metabolism ; Oxidation-Reduction ; Metal Nanoparticles/chemistry ; Charcoal/chemistry ; Waste Disposal, Fluid/methods ; Oxidoreductases ; }, abstract = {This study innovated constructed an activated carbon-loaded nano-zero-valent iron (nZVI-C) enhanced membrane aerated biofilm reactor (MABR) coupled partial nitritation/anammox (PN/A) system for optimizing nitrogen and antibiotics removal. Results showed that nitrogen and antibiotic removal efficiencies of 88.45 ± 0.14% and 89.90 ± 3.07% were obtained by nZVI-C, respectively. nZVI-C hastened Nitrosomonas enrichment (relative abundance raised from 2.85% to 12.28%) by increasing tryptophan content in EPS. Furthermore, nZVI-C proliferated amo gene by 3.92 times and directly generated electrons, stimulating Ammonia monooxygenase (AMO) co-metabolism activity. Concurrently, via antibiotic resistance genes (ARGs) horizontal transfer, Nitrosomonas synergized with Arenimonas and Comamonadaceae for efficient antibiotic removal. Moreover, nZVI-C mitigated antibiotics inhibition of electron transfer by proliferating genes for PN and anammox electron production (hao, hdh) and utilization (amo, hzs, nir). That facilitated electron transfer and synergistic substrate conversion between ammonia oxidizing bacteria (AOB) and anaerobic ammonia oxidizing bacteria (AnAOB). Finally, the high nitrogen removal efficiency of the MABR-PN/A system was achieved.}, }
@article {pmid38759390, year = {2024}, author = {Dang, MH and Cai, JN and Choi, HM and Kim, D and Oh, HW and Jeon, JG}, title = {Difference in formation of a dental multi-species biofilm according to substratum direction.}, journal = {Archives of oral biology}, volume = {164}, number = {}, pages = {106002}, doi = {10.1016/j.archoralbio.2024.106002}, pmid = {38759390}, issn = {1879-1506}, mesh = {*Biofilms ; *Actinomyces/physiology ; *Streptococcus mutans/physiology ; *Microscopy, Electron, Scanning ; *Saliva/microbiology ; *Streptococcus oralis/physiology ; *Bacterial Adhesion/physiology ; *Durapatite/chemistry ; Humans ; Surface Properties ; Hydrogen-Ion Concentration ; }, abstract = {OBJECTIVES: The aim of this study was to investigate the difference in dental biofilm formation according to substratum direction, using an artificial biofilm model.<br><br>METHODS: A three-species biofilm, consisting of Streptococcus mutans, Streptococcus oralis, and Actinomyces naeslundii, was formed on saliva-coated hydroxyapatite (sHA) discs oriented in three directions: downward (the discs placed in the direction of gravity), vertical (the discs placed parallel to the direction of gravity), and upward (the discs placed in opposite direction of gravity). The biofilms at 22&#xa0;h and 46&#xa0;h of age were analyzed using microbiological and biochemical methods, fluorescence-based assays, and scanning electron microscopy to investigate difference in bacterial adhesion, early and mature biofilm formation.<br><br>RESULTS: The biofilms formed in the upward direction displayed the most complex structure, with the highest number and biovolume of bacteria, as well as the lowest pH conditions at both time points. The vertical and downward directions, however, had only scattered and small bacterial colonies. In the 22-h-old biofilms, the proportion of S. oralis was similar to, or slightly higher than, that of S. mutans in all directions of substratum surfaces. However, in the 46-h-old biofilms, S. mutans became the dominant bacteria in all directions, especially in the vertical and upward directions.<br><br>CONCLUSIONS: The direction of the substratum surface could impact the proportion of bacteria and cariogenic properties of the multi-species biofilm. Biofilms in an upward direction may exhibit a higher cariogenic potential, followed by those in the vertical and downward directions, which could be related to gravity.}, }
@article {pmid38759062, year = {2024}, author = {Jiang, W and Zhang, Y and Yan, J and He, Z and Chen, W}, title = {Differences of protein expression in enterococcus faecalis biofilm during resistance to environmental pressures.}, journal = {Technology and health care : official journal of the European Society for Engineering and Medicine}, volume = {32}, number = {S1}, pages = {371-383}, pmid = {38759062}, issn = {1878-7401}, mesh = {*Biofilms ; *Enterococcus faecalis ; *Sodium Hypochlorite/pharmacology ; Proteomics/methods ; Bacterial Proteins/metabolism ; Humans ; Tandem Mass Spectrometry ; Hydrogen-Ion Concentration ; Chromatography, Liquid ; }, abstract = {BACKGROUND: Enterococcus faecalis biofilm was frequently found on the failed treated root canal wall, which survived by resisting disinfectant during endodontic treatment.Many researches have been conducted to explore the mechanisms of persistence of this pathogen in unfavorable conditions. However, no comprehensive proteomics studies have been conducted to investigate stress response in Enterococcus faecalis caused by alkali and NaOCl.<br><br>OBJECTIVE: Enterococcus faecalis (E.f) has been recognized as a main pathogen of refractory apical periodontitis, its ability to withstand environmental pressure is the key to grow in the environment of high alkaline and anti-bacterial drug that causes chronic infection in the root canal. This study aims to focus on the protein expression patterns of E.f biofilm under extreme pressure environment".<br><br>METHODS: Enterococcus faecalis biofilm model was established in vitro. Liquid Chromatograph-Mass Spectrometer (LC-MS/MS)-based label free quantitative proteomics approach was applied to compare differential protein expression under different environmental pressures (pH 10 and 5% sodium hypochlorite (NaOCl)). And then qPCR and Parallel Reaction Monitoring Verification (PRM) were utilized to verify the consequence of proteomics.<br><br>RESULTS: The number of taxa in this study was higher than those in previous studies, demonstrating the presence of a remarkable number of proteins in the groups of high alkaline and NaOCl. Proteins involved in ATP-binding cassette (ABC) transporter were significantly enriched in experimental samples. We identified a total of 15 highly expressed ABC transporters in the high alkaline environment pressure group, with 7 proteins greater than 1.5 times.<br><br>CONCLUSIONS: This study revealed considerable changes in expression of proteins in E.f biofilm during resistance to environmental pressures. The findings enriched our understanding of association between the differential expression proteins and environmental pressures.}, }
@article {pmid38758746, year = {2024}, author = {Jang, H and Song, W and Song, H and Kang, DK and Park, S and Seong, M and Jeong, HE}, title = {Sustainable Biofilm Inhibition Using Chitosan-Mesoporous Nanoparticle-Based Hybrid Slippery Composites.}, journal = {ACS applied materials &amp; interfaces}, volume = {16}, number = {21}, pages = {27728-27740}, doi = {10.1021/acsami.4c03053}, pmid = {38758746}, issn = {1944-8252}, mesh = {*Biofilms/drug effects ; *Chitosan/chemistry/pharmacology ; *Silicon Dioxide/chemistry/pharmacology ; *Nanoparticles/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; Porosity ; *Dimethylpolysiloxanes/chemistry/pharmacology ; Microbial Sensitivity Tests ; }, abstract = {In recent decades, extensive research has been directed toward mitigating microbial contamination and preventing biofilm formation. However, many conventional antibiofilm methods rely on hazardous and toxic substances, neglecting potential risks to human health and the environment. Moreover, these approaches often rely on single-strategy mechanisms, utilizing either bactericidal or fouling-resistant agents, which have shown limited efficacy in long-term biofilm suppression. In this study, we propose an efficient and sustainable biofilm-resistant slippery hybrid slippery composite. This composite integrates nontoxic and environmentally friendly materials including chitosan, silicone oil-infused polydimethylsiloxane, and mesoporous silica nanoparticles in a synergistic manner. Leveraging the bacteria-killing properties of chitosan and the antifouling capabilities of the silicone oil layer, the hybrid composite exhibits robust antibiofilm performance against both Gram-positive and Gram-negative bacteria. Furthermore, the inclusion of mesoporous silica nanoparticles enhances the oil absorption capacity and self-replenishing properties, ensuring exceptional biofilm inhibition even under harsh conditions such as exposure to high shear flow and prolonged incubation (7 days). This approach offers promising prospects for developing effective biofilm-resistant materials with a reduced environmental impact and improved long-term performance.}, }
@article {pmid38755634, year = {2024}, author = {Wongchai, M and Wongkaewkhiaw, S and Kanthawong, S and Roytrakul, S and Aunpad, R}, title = {Dual-function antimicrobial-antibiofilm peptide hybrid to tackle biofilm-forming Staphylococcus epidermidis.}, journal = {Annals of clinical microbiology and antimicrobials}, volume = {23}, number = {1}, pages = {44}, pmid = {38755634}, issn = {1476-0711}, support = {13/2563//National Research Council of Thailand (NRCT)/ ; }, mesh = {*Biofilms/drug effects ; *Staphylococcus epidermidis/drug effects/physiology ; Humans ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology/chemistry ; Hemolysis/drug effects ; Antimicrobial Peptides/pharmacology/chemistry ; Staphylococcal Infections/drug therapy/microbiology ; }, abstract = {BACKGROUND: Due to their resistance and difficulty in treatment, biofilm-associated infections are problematic among hospitalized patients globally and account for 60% of all bacterial infections in humans. Antibiofilm peptides have recently emerged as an alternative treatment since they can be effectively designed and exert a different mode of biofilm inhibition and eradication.<br><br>METHODS: A novel antibiofilm peptide, BiF, was designed from the conserved sequence of 18 &#x3b1;-helical antibiofilm peptides by template-assisted technique and its activity was improved by hybridization with a lipid binding motif (KILRR). Novel antibiofilm peptide derivatives were modified by substituting hydrophobic amino acids at positions 5 or 7, and both, with positively charged lysines (L5K, L7K). These peptide derivatives were tested for antibiofilm and antimicrobial activities against biofilm-forming Staphylococcus epidermidis and multiple other microbes using crystal violet and broth microdilution assays, respectively. To assess their impact on mammalian cells, the toxicity of peptides was determined through hemolysis and cytotoxicity assays. The stability of candidate peptide, BiF2_5K7K, was assessed in human serum and its secondary structure in bacterial membrane-like environments was analyzed using circular dichroism. The action of BiF2_5K7K on planktonic S. epidermidis and its effect on biofilm cell viability were assessed via viable counting assays. Its biofilm inhibition mechanism was investigated through confocal laser scanning microscopy and transcription analysis. Additionally, its ability to eradicate mature biofilms was examined using colony counting. Finally, a preliminary evaluation involved coating a catheter with BiF2_5K7K to assess its preventive efficacy against S. epidermidis biofilm formation on the catheter and its surrounding area.<br><br>RESULTS: BiF2_5K7K, the modified antibiofilm peptide, exhibited dose-dependent antibiofilm activity against S. epidermidis. It inhibited biofilm formation at subinhibitory concentrations by altering S. epidermidis extracellular polysaccharide production and quorum-sensing gene expression. Additionally, it exhibited broad-spectrum antimicrobial activity and no significant hemolysis or toxicity against mammalian cell lines was observed. Its activity is retained when exposed to human serum. In bacterial membrane-like environments, this peptide formed an &#x3b1;-helix amphipathic structure. Within 4&#xa0;h, a reduction in the number of S. epidermidis colonies was observed, demonstrating the fast action of this peptide. As a preliminary test, a BiF2_5K7K-coated catheter was able to prevent the development of S. epidermidis biofilm both on the catheter surface and in its surrounding area.<br><br>CONCLUSIONS: Due to the safety and effectiveness of BiF2_5K7K, we suggest that this peptide be further developed to combat biofilm infections, particularly those of biofilm-forming S. epidermidis.}, }
@article {pmid38755426, year = {2024}, author = {Lopes, APR and Andrade, AL and Pinheiro, AA and de Sousa, LS and Malveira, EA and Oliveira, FFM and de Albuquerque, CC and Teixeira, EH and de Vasconcelos, MA}, title = {Lippia grata Essential Oil Acts Synergistically with Ampicillin Against Staphylococcus aureus and its Biofilm.}, journal = {Current microbiology}, volume = {81}, number = {7}, pages = {176}, pmid = {38755426}, issn = {1432-0991}, support = {APQ-00224-2//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado de Minas Gerais/ ; APQ-02972-22//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado de Minas Gerais/ ; }, mesh = {*Biofilms/drug effects ; *Staphylococcus aureus/drug effects/physiology ; *Ampicillin/pharmacology ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology ; *Drug Synergism ; *Oils, Volatile/pharmacology ; *Lippia/chemistry ; Plant Extracts/pharmacology ; Plant Leaves/chemistry ; }, abstract = {Antimicrobial resistance (AMR) presents a global challenge as microorganisms evolve to withstand the effects of antibiotics. In addition, the improper use of antibiotics significantly contributes to the AMR acceleration. Essential oils have garnered attention for their antimicrobial potential. Indeed, essential oils extracted from plants contain compounds that exhibit antibacterial activity, including against resistant microorganisms. Hence, this study aimed to evaluate the antimicrobial and antibiofilm activity of the essential oil (EO) extracted from Lippia grata and its combination with ampicillin against Staphylococcus aureus strains (ATCC 25923, ATCC 700698, and JKD6008). The plant material (leaves) was gathered in Mossoro, RN, and the EO was obtained using the hydrodistillation method with the Clevenger apparatus. The antimicrobial activity of the EO was assessed through minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays. Antibiofilm activity was evaluated by measuring biomass using crystal violet (CV) staining, viable cell counting, and analysis of preformed biofilms. In addition, the synergistic effects of the EO in combination with ampicillin were examined by scanning electron and confocal microscopy. The EO displayed a MIC value of 2.5 mg/mL against all tested S. aureus strains and an MBC only against S. aureus JKD6008 at 2.5 mg/mL. L. grata EO caused complete biofilm inhibition at concentrations ranging from 10 to 0.312 mg/mL against S. aureus ATCC 25923 and 10 to 1.25 mg/mL against S. aureus ATCC 700698 and S. aureus JKD6008. In the viable cell quantification assay, there was a reduction in CFU ranging from 1.0 to 8.0 logs. The combination of EO with ampicillin exhibited a synergistic effect against all strains. Moreover, the combination showed a significantly inhibiting biofilm formation and eradicating preformed biofilms. Furthermore, the EO and ampicillin (individually and in combination) altered the cellular morphology of S. aureus cells. Regarding the mechanism, the results revealed that L. grata EO increased membrane permeability and caused significant membrane damage. Concerning the synergy mechanism, the results revealed that the combination of EO and ampicillin increases membrane permeability and causes considerable membrane damage, further inhibiting bacteria synergistically. The findings obtained here suggest that L. grata EO in combination with ampicillin could be a viable treatment option against S. aureus infections, including MRSA strain.}, }
@article {pmid38755164, year = {2024}, author = {Fernández-Calvet, A and Matilla-Cuenca, L and Izco, M and Navarro, S and Serrano, M and Ventura, S and Blesa, J and Herráiz, M and Alkorta-Aranburu, G and Galera, S and Ruiz de Los Mozos, I and Mansego, ML and Toledo-Arana, A and Alvarez-Erviti, L and Valle, J}, title = {Gut microbiota produces biofilm-associated amyloids with potential for neurodegeneration.}, journal = {Nature communications}, volume = {15}, number = {1}, pages = {4150}, pmid = {38755164}, issn = {2041-1723}, support = {PC133-134-135 MICROPROGEN//Departamento de Educaci&#xf3;n, Gobierno de Navarra (Department of Education, Government of Navarra)/ ; }, mesh = {Animals ; *Gastrointestinal Microbiome ; *Caenorhabditis elegans/metabolism/microbiology ; Humans ; *Biofilms/growth &amp; development ; *Amyloid/metabolism ; *alpha-Synuclein/metabolism/genetics ; *Parkinson Disease/metabolism/microbiology/pathology ; Mice ; *Dopaminergic Neurons/metabolism ; Autophagy ; Neurodegenerative Diseases/metabolism ; Mice, Inbred C57BL ; Bacterial Proteins/metabolism/genetics ; Brain/metabolism/pathology ; Synucleinopathies/metabolism/pathology ; }, abstract = {Age-related neurodegenerative diseases involving amyloid aggregation remain one of the biggest challenges of modern medicine. Alterations in the gastrointestinal microbiome play an active role in the aetiology of neurological disorders. Here, we dissect the amyloidogenic properties of biofilm-associated proteins (BAPs) of the gut microbiota and their implications for synucleinopathies. We demonstrate that BAPs are naturally assembled as amyloid-like fibrils in insoluble fractions isolated from the human gut microbiota. We show that BAP genes are part of the accessory genomes, revealing microbiome variability. Remarkably, the abundance of certain BAP genes in the gut microbiome is correlated with Parkinson's disease (PD) incidence. Using cultured dopaminergic neurons and Caenorhabditis elegans models, we report that BAP-derived amyloids induce α-synuclein aggregation. Our results show that the chaperone-mediated autophagy is compromised by BAP amyloids. Indeed, inoculation of BAP fibrils into the brains of wild-type mice promote key pathological features of PD. Therefore, our findings establish the use of BAP amyloids as potential targets and biomarkers of α-synucleinopathies.}, }
@article {pmid38755018, year = {2024}, author = {Daca, A and Piechowicz, L and Wiśniewska, K and Bryl, E and Witkowski, JM and Jarzembowski, T}, title = {Both biofilm cytotoxicity and monocytes' adhesion may be used as estimators of enterococcal virulence.}, journal = {Letters in applied microbiology}, volume = {77}, number = {5}, pages = {}, doi = {10.1093/lambio/ovae047}, pmid = {38755018}, issn = {1472-765X}, support = {2014-2020//European Regional Development Fund/ ; 21-0012/21/658//Ministry of Science and Higher Education, Republic of Poland/ ; }, mesh = {*Biofilms/growth &amp; development ; *Monocytes/microbiology ; Humans ; Virulence ; Bacterial Adhesion ; Gram-Positive Bacterial Infections/microbiology ; Bacterial Proteins/metabolism/genetics ; Enterococcus/pathogenicity ; Poland ; Feces/microbiology ; }, abstract = {Our study aimed to identify markers of enterococci's virulence potential by evaluating the properties of strains of different sites of isolation. Enterococcal strains were isolated as commensals from faeces and as invasive strains from the urine and blood of patients from the University Clinical Centre, Gdańsk, Poland. Changes in monocytes' susceptibility to the cytotoxic activity of isolates of different origins and their adherence to biofilm were evaluated using a flow cytometer. The bacterial protein profile was estimated by matrix assisted laser desorption ionization-time of flight mass spectrometer. The cytotoxicity of biofilm and monocytes' adherence to it were the most accurate factors in predicting the prevalence of the strain in the specific niche. Additionally, a bacterial protein with mass-to-charge ratio (m/z) 5000 was found to be responsible for the increased bacterial cytotoxicity, while monocytes' decreased adherence to biofilm was linked with the presence of proteins either with m/z 3330 or 2435. The results illustrate that monocytes' reaction when exposed to the bacterial biofilm can be used as an estimator of pathogens' virulence potential. The observed differences in monocytes' response are explainable by the bacterial proteins' profile. Additionally, the results indicate that the features of both bacteria and monocytes impact the outcome of the infection.}, }
@article {pmid38752875, year = {2024}, author = {Sun, Y and Zhao, H and Pu, F and Liu, H and Chen, L and Ren, J and Qu, X}, title = {On-Demand Activatable and Integrated Bioorthogonal Nanocatalyst against Biofilm-Associated Infections.}, journal = {Advanced healthcare materials}, volume = {13}, number = {23}, pages = {e2400899}, doi = {10.1002/adhm.202400899}, pmid = {38752875}, issn = {2192-2659}, support = {20240101190JC//Natural Science Foundation of Jilin Province/ ; 2021YFF1200700//National Key Research and Development Program of China/ ; 2019YFA0709202//National Key Research and Development Program of China/ ; 22237006//National Natural Science Foundation of China/ ; 22277117//National Natural Science Foundation of China/ ; }, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; Catalysis ; *Hyaluronoglucosaminidase/metabolism ; *Reactive Oxygen Species/metabolism ; Animals ; Mice ; Prodrugs/chemistry/pharmacology ; Staphylococcus aureus/drug effects ; Humans ; Escherichia coli/drug effects ; }, abstract = {Bioorthogonal chemistry has emerged as a powerful tool for manipulating biological processes. However, difficulties in controlling the exact location and on-demand catalytic synthesis limit its application in biological systems. Herein, this work constructs an activatable bioorthogonal system integrating a shielded catalyst and prodrug molecules to combat biofilm-associated infections. The catalytic species is activated in response to the hyaluronidase (HAase) secreted by the bacteria and the acidic pH of the biofilm, which is accompanied by the release of prodrugs, to achieve the bioorthogonal catalytic synthesis of antibacterial molecules in situ. Moreover, the system can produce reactive oxygen species (ROS) to disperse bacterial biofilms, enabling the antibacterial molecules to penetrate the biofilm and eliminate the bacteria within it. This study promotes the design of efficient and safe bioorthogonal catalysts and the development of bioorthogonal chemistry-mediated antibacterial strategies.}, }
@article {pmid38752844, year = {2024}, author = {Bhatt, P and Sharpe, A and Staines, K and Wallace, N and Withers, A}, title = {Topical desiccating agent (DEBRICHEM): an accessible debridement option for removing biofilm in hard-to-heal wounds.}, journal = {Journal of wound care}, volume = {33}, number = {Sup5b}, pages = {S4-S11}, doi = {10.12968/jowc.2024.33.Sup5b.S4}, pmid = {38752844}, issn = {0969-0700}, mesh = {Humans ; Administration, Topical ; *Biofilms ; *Debridement/methods ; *Wound Healing ; Wound Infection/therapy ; Wounds and Injuries/therapy ; }, abstract = {It is now assumed that all hard-to-heal wounds contain biofilm. Debridement plays a key role in wound-bed preparation, as it can remove biofilm along with the devitalised tissue, potentially leaving a clean wound bed that is more likely to progress towards healing. The gold standard methods of debridement (surgical and sharp) are the least used, as they require specialist training and are often not readily available at the point of need. Most other methods can be used by generalists but are slower. They all need regular applications. The topical desiccating agent DEBRICHEM is an innovative alternative, as it is fast, effective and can be used in all clinical settings, as well as typically requiring only a single use. This article describes best practice for achieving optimal outcomes with its use.}, }
@article {pmid38751998, year = {2024}, author = {Shang, X and Bai, H and Fan, L and Zhang, X and Zhao, X and Liu, Z}, title = {In vitro biofilm formation of Gardnerella vaginalis and Escherichia coli associated with bacterial vaginosis and aerobic vaginitis.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1387414}, pmid = {38751998}, issn = {2235-2988}, mesh = {*Biofilms/growth &amp; development ; *Gardnerella vaginalis/physiology/growth &amp; development ; Humans ; *Escherichia coli/physiology ; Female ; *Vaginosis, Bacterial/microbiology ; *Microscopy, Electron, Scanning ; Microscopy, Confocal ; Vagina/microbiology ; Anaerobiosis ; Coculture Techniques ; Vaginitis/microbiology ; }, abstract = {OBJECTIVE: To determine the optimum biofilm formation ratio of Gardnerella vaginalis (G. vaginalis) in a mixed culture with Escherichia coli (E. coli).<br><br>METHODS: G. vaginalis ATCC14018, E. coli ATCC25922, as well as five strains of G. vaginalis were selected from the vaginal sources of patients whose biofilm forming capacity was determined by the Crystal Violet method. The biofilm forming capacity of E. coli in anaerobic and non-anaerobic environments were compared using the identical assay. The Crystal Violet method was also used to determine the biofilm forming capacity of a co-culture of G. vaginalis and E. coli in different ratios. After Live/Dead staining, biofilm thickness was measured using confocal laser scanning microscopy, and biofilm morphology was observed by scanning electron microscopy.<br><br>RESULTS: The biofilm forming capacity of E. coli under anaerobic environment was similar to that in a 5% CO2 environment. The biofilm forming capacity of G. vaginalis and E. coli was stronger at 10[6]:10[5] CFU/mL than at other ratios (P<0.05). Their thicknesses were greater at 10[6]:10[5] CFU/mL than at the other ratios, with the exception of 10[6]:10[2] CFU/mL (P<0.05), under laser scanning microscopy. Scanning electron microscopy revealed increased biofilm formation at 10[6]:10[5] CFU/mL and 10[6]:10[2] CFU/mL, but no discernible E. coli was observed at 10[6]:10[2] CFU/mL.<br><br>CONCLUSION: G. vaginalis and E. coli showed the greatest biofilm forming capacity at a concentration of 10[6]:10[5] CFU/mL at 48 hours and could be used to simulate a mixed infection of bacterial vaginosis and aerobic vaginitis in vitro.}, }
@article {pmid38751716, year = {2024}, author = {Kaplan, JB and Cywes-Bentley, C and Pier, GB and Yakandawala, N and Sailer, M and Edwards, MS and Kridin, K}, title = {Poly-β-(1→6)-N-acetyl-D-glucosamine mediates surface attachment, biofilm formation, and biocide resistance in Cutibacterium acnes.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1386017}, pmid = {38751716}, issn = {1664-302X}, abstract = {BACKGROUND: The commensal skin bacterium Cutibacterium acnes plays a role in the pathogenesis of acne vulgaris and also causes opportunistic infections of implanted medical devices due to its ability to form biofilms on biomaterial surfaces. Poly-β-(1→6)-N-acetyl-D-glucosamine (PNAG) is an extracellular polysaccharide that mediates biofilm formation and biocide resistance in a wide range of bacterial pathogens. The objective of this study was to determine whether C. acnes produces PNAG, and whether PNAG contributes to C. acnes biofilm formation and biocide resistance in vitro.<br><br>METHODS: PNAG was detected on the surface of C. acnes cells by fluorescence confocal microscopy using the antigen-specific human IgG1 monoclonal antibody F598. PNAG was detected in C. acnes biofilms by measuring the ability of the PNAG-specific glycosidase dispersin B to inhibit biofilm formation and sensitize biofilms to biocide killing.<br><br>RESULTS: Monoclonal antibody F598 bound to the surface of C. acnes cells. Dispersin B inhibited attachment of C. acnes cells to polystyrene rods, inhibited biofilm formation by C. acnes in glass and polypropylene tubes, and sensitized C. acnes biofilms to killing by benzoyl peroxide and tetracycline.<br><br>CONCLUSION: C. acnes produces PNAG, and PNAG contributes to C. acnes biofilm formation and biocide resistance in vitro. PNAG may play a role in C. acnes skin colonization, biocide resistance, and virulence in vivo.}, }
@article {pmid38751055, year = {2024}, author = {Cao, B and Zhang, J and Ma, Y and Wang, Y and Li, Y and Wang, R and Cao, D and Yang, Y and Zhang, R}, title = {Dual-Polymer Functionalized Melanin-AgNPs Nanocomposite with Hydroxyapatite Binding Ability to Penetrate and Retain in Biofilm Sequentially Treating Periodontitis.}, journal = {Small (Weinheim an der Bergstrasse, Germany)}, volume = {20}, number = {37}, pages = {e2400771}, doi = {10.1002/smll.202400771}, pmid = {38751055}, issn = {1613-6829}, support = {2023YFC3402800//National Key Research and Development Program of China/ ; 82120108016//National Natural Science Foundation of China/ ; 82071987//National Natural Science Foundation of China/ ; 202104010910010//Key Laboratory of Nano-imaging and Drug-loaded Preparation of Shanxi Province/ ; 20210302124035//Shanxi Province Science Foundation for Youths/ ; 20210302124285//Shanxi Province Science Foundation for Youths/ ; 202104010911026//Shanxi Center of Technology Innovation for Controlled and Sustained Release of Nano-drugs/ ; 2022RC14//Scientific Research Foundation of Shanxi Bethune Hospital/ ; 2023GZRZ02//National Natural Science Foundation Seed Player Project of Shanxi Bethune Hospital/ ; }, mesh = {*Biofilms/drug effects ; *Melanins/chemistry/metabolism ; *Periodontitis/drug therapy/microbiology ; *Durapatite/chemistry ; *Nanocomposites/chemistry ; *Silver/chemistry/pharmacology ; Animals ; *Polymers/chemistry ; Anti-Bacterial Agents/pharmacology/chemistry ; Metal Nanoparticles/chemistry ; Reactive Oxygen Species/metabolism ; }, abstract = {Periodontitis is the leading cause of adult tooth missing. Thorny bacterial biofilm and high reactive oxygen species (ROS) levels in tissue are key elements for the periodontitis process. It is meaningful to develop an advanced therapeutic system with sequential antibacterial/ antioxidant ability to meet the overall goals of periodontitis therapy. Herein, a dual-polymer functionalized melanin-AgNPs (P/D-MNP-Ag) with biofilm penetration, hydroxyapatite binding, and sequentially treatment ability are fabricated. Polymer enriched with 2-(Dimethylamino)ethyl methacrylate (D), can be protonated in an acid environment with enhanced positive charge, promoting penetration in biofilm. The other polymer is rich in phosphate group (P) and can chelate Ca[2+], promoting the polymer to adhere to the hydroxyapatite surface. Melanin has good ROS scavenging and photothermal abilities, after in situ reduction Ag, melanin-AgNPs composite has sequentially transitioned between antibacterial and antioxidative ability due to heat and acid accelerated Ag[+] release. The released Ag[+] and heat have synergistic antibacterial effects for bacterial killing. With Ag[+] consumption, the antioxidant ability of MNP recovers to scavenge ROS in the inflammatory area. When applied in the periodontitis model, P/D-MNP-Ag has good therapeutical effects to ablate biofilm, relieve inflammation state, and reduce alveolar bone loss. P/D-MNP-Ag with sequential treatment ability provides a reference for developing advanced oral biofilm eradication systems.}, }
@article {pmid38750998, year = {2024}, author = {Liu, X and Wang, D and Qi, X and Gu, Y and Huang, X and Liang, P}, title = {Propionate outperforms conventional acetate as electron donors for highly-sensitive electrochemical active biofilm sensors in water biotoxicity early-warning.}, journal = {Environmental research}, volume = {252}, number = {Pt 4}, pages = {119127}, doi = {10.1016/j.envres.2024.119127}, pmid = {38750998}, issn = {1096-0953}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Acetates ; *Propionates ; *Electrochemical Techniques/instrumentation/methods ; Water Pollutants, Chemical/analysis/toxicity ; Biosensing Techniques/instrumentation/methods ; }, abstract = {With the ability to generate in situ real-time electric signals, electrochemically active biofilm (EAB) sensors have attracted wide attention as a promising water biotoxicity early-warning device. Organic matters serving as the electron donors potentially affect the electric signal's output and the sensitivity of the EAB sensor. To explore the influence of organic matters on EAB sensor's performance, this study tested six different organic matters during the sensor's inoculation. Besides the acetate, a conventional and widely used organic matter, propionate and lactate were also found capable of starting up the sensor. Moreover, the propionate-fed (PF) sensor delivered the highest sensitivity, which are respectively 1.4 times and 2.8 times of acetate-fed (AF) sensor and lactate-fed (LF) sensor. Further analysis revealed that EAB of PF sensor had more vulnerable intracellular metabolism than the others, which manifested as the most severe energy metabolic suppression and reactive oxygen species attack. Regarding the microbial function, a two-component system that was deemed as an environment awareness system was found in the EAB of PF, which also contributed to its high sensitivity. Finally, PF sensor was tested in real water environment to deliver early-warning signals.}, }
@article {pmid38749386, year = {2024}, author = {Aragão, MGB and He, X and Aires, CP and Corona, SAM}, title = {Epigallocatechin gallate reduces the virulence of cariogenic Streptococcus mutans biofilm by affecting the synthesis of biofilm matrix components.}, journal = {Archives of oral biology}, volume = {164}, number = {}, pages = {105990}, doi = {10.1016/j.archoralbio.2024.105990}, pmid = {38749386}, issn = {1879-1506}, mesh = {*Biofilms/drug effects ; *Streptococcus mutans/drug effects ; *Catechin/pharmacology/analogs &amp; derivatives ; Virulence/drug effects ; *Microscopy, Confocal ; *Microscopy, Electron, Scanning ; Dental Caries/microbiology ; Hydrogen-Ion Concentration ; Microbial Viability/drug effects ; Polysaccharides, Bacterial ; Dental Enamel/drug effects/microbiology ; }, abstract = {INTRODUCTION: There have been reports on the effects of epigallocatechin gallate (EGCG) against Streptococcus mutans viability and acidogenesis. However, the effects of EGCG on the virulence of S. mutans biofilm development have yet to be fully investigated using validated cariogenic biofilm models.<br><br>OBJECTIVE: Thus, this study aimed to evaluate the effects of EGCG on S. mutans biofilm virulence using a validated cariogenic model and clinically relevant treatment regimens, twice a day for 1.5&#xa0;min.<br><br>METHODS: Effects of EGCG on bacterial viability, polyssacharide synthesis and biofilm acidogenesis were evaluated. The morphology and 3D structure of the biofilms were evaluated by scanning electron (SEM) and confocal laser scanning microscopy, respectively.<br><br>RESULTS: No significant change in S. mutans viability or culture medium pH were observed when comparing EGCG-treated and NaCl-treated biofilms. EGCG significantly reduced the accumulation of soluble and insoluble polysaccharides, resulting in the formation of a biofilm with interspaced exopolysaccharide-microcolony complexes unevenly distributed on enamel. The SEM images of the biofilm treated with EGCG depict multilayers of cells arranged in short chains of microorganisms adhered to an unstructured matrix, which is not continuous and does not enmesh or protect the microorganisms entirely. Importantly, confocal images demonstrated that treatment with EGCG affected the 3D structure and organization of S. mutans biofilm, which presented a biofilm matrix more confined to the location of the microcolonies.<br><br>CONCLUSION: In conclusion, EGCG lowered the virulence of S. mutans matrix-rich biofilm by reducing the synthesis of biofilm matrix components, altering the biofilm matrix structure, organization, and distribution.}, }
@article {pmid38748449, year = {2024}, author = {Mishra, AH and Mohan, S and Gutti, P and Krishna, S and Sundaraman, S and Chakraborti, S and Jaiswal, AK and Nambi Raj, NA and Mishra, D}, title = {Bioselective and Radiopaque Zinc-Biopolymeric Complex-Based Porous Biomaterials Promote Mammalian Tissue Ingrowth In Vivo While Inhibiting Microbial Biofilm Gene Expression and Biofilm Formation.}, journal = {ACS applied bio materials}, volume = {7}, number = {6}, pages = {3701-3713}, doi = {10.1021/acsabm.4c00013}, pmid = {38748449}, issn = {2576-6422}, mesh = {*Biofilms/drug effects ; *Zinc/chemistry/pharmacology ; *Biocompatible Materials/chemistry/pharmacology ; *Staphylococcus aureus/drug effects/physiology ; Animals ; *Materials Testing ; Porosity ; Rats ; Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; Particle Size ; Chitosan/chemistry/pharmacology ; Microbial Sensitivity Tests ; Tissue Scaffolds/chemistry ; }, abstract = {Metal-organic complexes have shown astounding bioactive properties; however, they are rarely explored as biomaterials. Recent studies showed that carboxymethyl-chitosan (CMC) genipin-conjugated zinc biomimetic scaffolds have unique bioselective properties. The biomaterial was reported to be mammalian cell-friendly; at the same time, it was found to discourage microbial biofilm formation on its surface, which seemed to be a promising solution to addressing the problem of trauma-associated biofilm formation and development of antimicrobial resistance. However, the mechanically frail characteristics and zinc overload raise concerns and limit the potential of the said biomaterials. Hence, the present work is focused on improving the strength of the earlier scaffold formulations, testing its in vivo efficacy and reaffirming its action against biofilm-forming microbe Staphylococcus aureus. Scaling up of CMC proportion increased rigidity, and 8% CMC was found to be the ideal concentration for robust scaffold fabrication. Freeze-dried CMC scaffolds with or without genipin (GP) cross-linking were conjugated with zinc using 2 M zinc acetate solution. Characterization results indicated that the CMC-Zn scaffolds, without genipin, showed mechanical properties close to bone fillers, resist in vitro enzymatic degradation until 4 weeks, are porous in nature, and have radiopacity close to mandibular bones. Upon implantation in a subcutaneous pocket of Wistar rats, the scaffolds showed tissue in-growth with simultaneous degradation without any signs of toxicity past 28 days. Neither were there any signs of toxicity in any of the vital organs. Considering many superior properties among the other formulations, the CMC-Zn scaffolds were furthered for biofilm studies. CMC-Zn showed negligible S. aureus biofilm formation on its surface as revealed by an alamar blue-based study. RT-PCR analysis revealed that CMC-Zn downregulated the expression of pro-biofilm effector genes such as icaC and clfB. A protein docking study predicted the inhibitory mechanism of CMC-Zn. Although it binds strongly when alone, at high density, it may cause inactivation of the transmembrane upstream activators of the said genes, thereby preventing their dimerization and subsequent inactivation of the effector genes. In conclusion, zinc-conjugated carboxymethyl-chitosan scaffolds are mechanically robust, porous, yet biodegradable, harmless to the host in the long term, they are radiopaque and prevent biofilm gene expression in notorious microbes; hence, they could be a suitable candidate for bone filler applications.}, }
@article {pmid38746970, year = {2024}, author = {Fan, D and Xie, R and Liu, X and Li, H and Luo, Z and Li, Y and Chen, F and Zeng, W}, title = {A peptide-based pH-sensitive antibacterial hydrogel for healing drug-resistant biofilm-infected diabetic wounds.}, journal = {Journal of materials chemistry. B}, volume = {12}, number = {22}, pages = {5525-5534}, doi = {10.1039/d4tb00594e}, pmid = {38746970}, issn = {2050-7518}, mesh = {*Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; *Hydrogels/chemistry/pharmacology/chemical synthesis ; *Biofilms/drug effects ; *Wound Healing/drug effects ; Hydrogen-Ion Concentration ; Animals ; Mice ; Microbial Sensitivity Tests ; Diabetic Foot/drug therapy ; Antimicrobial Peptides/chemistry/pharmacology ; Humans ; Diabetes Mellitus, Experimental/drug therapy ; Drug Resistance, Bacterial/drug effects ; Photosensitizing Agents/chemistry/pharmacology/chemical synthesis ; Chitosan/chemistry/pharmacology ; }, abstract = {Diabetic foot ulcers are a significant complication affecting roughly 15% of diabetic patients. These chronic wounds can be incredibly burdensome, leading to high treatment costs, potential amputations, and additional health complications. Microbiological studies reveal that bacterial infections are the primary culprit behind delayed wound healing. To solve the problem of infection at the wound site, the most fundamental thing is to kill the pathogenic bacteria. Herein, a neoteric strategy to construct novel antibacterial hydrogel COA-T3 that combined photosensitizers (PSs) and antimicrobial peptides (AMPs) via covalent coupling was proposed. Hydrogel COA-T3 composed of quaternized chitosan (QCS) and oxidized dextran (OD) was constructed for co-delivery of the photosensitizer TPI-PN and the antimicrobial peptide HHC10. In vitro and in vivo experiments demonstrated remarkable effectiveness of COA-T3 against drug-resistant bacteria. Furthermore, the hydrogel significantly promoted healing of diabetic infected wounds. This enhanced antibacterial activity is attributed to the pH-sensitive release of both PSs and AMPs within the hydrogel. Additionally, COA-T3 exhibits excellent biocompatibility, making it a promising candidate for wound dressing materials. These findings indicated that the COA-T3 hydrogel is a promising wound dressing material for promoting the healing of diabetic foot ulcers by providing an environment conducive to improved wound healing in diabetic patients.}, }
@article {pmid38746121, year = {2024}, author = {García-Bayona, L and Said, N and Coyne, MJ and Flores, K and Elmekki, NM and Sheahan, ML and Camacho, AG and Hutt, K and Yildiz, FH and Kovács, &#xc1;T and Waldor, MK and Comstock, LE}, title = {A pervasive large conjugative plasmid mediates multispecies biofilm formation in the intestinal microbiota increasing resilience to perturbations.}, journal = {bioRxiv : the preprint server for biology}, volume = {}, number = {}, pages = {}, doi = {10.1101/2024.04.29.590671}, pmid = {38746121}, issn = {2692-8205}, support = {K99 AI167064/AI/NIAID NIH HHS/United States ; P30 DK042086/DK/NIDDK NIH HHS/United States ; R00 AI167064/AI/NIAID NIH HHS/United States ; R25 GM109439/GM/NIGMS NIH HHS/United States ; }, abstract = {Although horizontal gene transfer is pervasive in the intestinal microbiota, we understand only superficially the roles of most exchanged genes and how the mobile repertoire affects community dynamics. Similarly, little is known about the mechanisms underlying the ability of a community to recover after a perturbation. Here, we identified and functionally characterized a large conjugative plasmid that is one of the most frequently transferred elements among Bacteroidales species and is ubiquitous in diverse human populations. This plasmid encodes both an extracellular polysaccharide and fimbriae, which promote the formation of multispecies biofilms in the mammalian gut. We use a hybridization-based approach to visualize biofilms in clarified whole colon tissue with unprecedented 3D spatial resolution. These biofilms increase bacterial survival to common stressors encountered in the gut, increasing strain resiliency, and providing a rationale for the plasmid's recent spread and high worldwide prevalence.}, }
@article {pmid38745848, year = {2024}, author = {Pokhrel, S and Sharma, N and Aryal, S and Khadka, R and Thapa, TB and Pandey, P and Joshi, G}, title = {Detection of Biofilm Production and Antibiotic Susceptibility Pattern among Clinically Isolated Staphylococcus aureus.}, journal = {Journal of pathogens}, volume = {2024}, number = {}, pages = {2342468}, pmid = {38745848}, issn = {2090-3057}, abstract = {AIM: The increasing antibiotic resistance and the ability to form biofilms in medical devices have become the leading cause of severe infections associated with Staphylococcus aureus (S. aureus). Since the bacteria living in biofilms can exhibit 10- to 1,000-fold increase in antibiotic resistance and implicate chronic infectious diseases, the detection of S. aureus ability to form biofilms is of great importance for managing, minimizing, and effectively treating infections caused by it. This study aimed to compare the tube and tissue culture methods to detect biofilm production and antibiotic susceptibility in MRSA and MSSA.<br><br>MATERIALS AND METHODS: The S. aureus isolates were identified by the examination of the colony morphology, Gram staining, and various biochemical tests. Antimicrobial susceptibility testing of all isolates was performed by the modified Kirby-Bauer disc diffusion method as recommended by CLSI guidelines. MRSA screening was performed phenotypically using a cefoxitin disc (30&#x2009;&#xb5;g). Isolates were tested for inducible resistance using the D-test, and two phenotypic methods detected biofilm formation.<br><br>RESULTS: Among 982 nonrepeated clinical specimens, S. aureus was isolated from 103 (10.48%). Among 103 clinical isolates of S. aureus, 54 (52.42%) isolates were MRSA, and 49 (47.57%) were MSSA. Among 54 MRSA isolates, the inducible MLSB phenotype was observed in 23/54 (42.59%) with a positive D-test. By TCP method, 26 (48.1%) MRSA isolates were strong biofilm producers, whereas, among all MSSA isolates, only 6 (12.2%) were strong biofilm producers.<br><br>CONCLUSION: MRSA showed strong biofilm production in comparison with MSSA. The TCP method is a recommended reliable method to detect the biofilm among S. aureus isolates, and the TM method could be useful for the screening of biofilm production in S. aureus in the routine clinical laboratory.}, }
@article {pmid38744766, year = {2024}, author = {Er-Rahmani, S and Errabiti, B and Matencio, A and Trotta, F and Latrache, H and Koraichi, SI and Elabed, S}, title = {Plant-derived bioactive compounds for the inhibition of biofilm formation: a comprehensive review.}, journal = {Environmental science and pollution research international}, volume = {31}, number = {24}, pages = {34859-34880}, pmid = {38744766}, issn = {1614-7499}, mesh = {*Biofilms/drug effects ; Plants ; Biological Products/pharmacology/chemistry ; Quorum Sensing/drug effects ; }, abstract = {Biofilm formation is a widespread phenomenon that impacts different fields, including the food industry, agriculture, health care and the environment. Accordingly, there is a serious need for new methods of managing the problem of biofilm formation. Natural products have historically been a rich source of varied compounds with a wide variety of biological functions, including antibiofilm agents. In this review, we critically highlight and discuss the recent progress in understanding the antibiofilm effects of several bioactive compounds isolated from different plants, and in elucidating the underlying mechanisms of action and the factors influencing their adhesion. The literature shows that bioactive compounds have promising antibiofilm potential against both Gram-negative and Gram-positive bacterial and fungal strains, via several mechanisms of action, such as suppressing the formation of the polymer matrix, limiting O2 consumption, inhibiting microbial DNA replication, decreasing hydrophobicity of cell surfaces and blocking the quorum sensing network. This antibiofilm activity is influenced by several environmental factors, such as nutritional cues, pH values, O2 availability and temperature. This review demonstrates that several bioactive compounds could mitigate the problem of biofilm production. However, toxicological assessment and pharmacokinetic investigations of these molecules are strongly required to validate their safety.}, }
@article {pmid38744691, year = {2024}, author = {Pradhan, L and Sah, P and Nayak, M and Upadhyay, A and Pragya, P and Tripathi, S and Singh, G and Mounika, B and Paik, P and Mukherjee, S}, title = {Biosynthesized silver nanoparticles prevent bacterial infection in chicken egg model and mitigate biofilm formation on medical catheters.}, journal = {Journal of biological inorganic chemistry : JBIC : a publication of the Society of Biological Inorganic Chemistry}, volume = {29}, number = {3}, pages = {353-373}, pmid = {38744691}, issn = {1432-1327}, support = {R22-2922732087//Royal Society of Chemistry/ ; }, mesh = {Animals ; *Biofilms/drug effects ; *Silver/chemistry/pharmacology ; *Metal Nanoparticles/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; *Catheters/microbiology ; Chickens ; Escherichia coli/drug effects/physiology ; Microbial Sensitivity Tests ; Humans ; Chick Embryo ; Rats ; Plant Extracts/pharmacology/chemistry ; Plant Leaves/chemistry/microbiology ; }, abstract = {Investigating the application of innovative antimicrobial surface coatings on medical devices is an important field of research. Many of these coatings have significant drawbacks, including biocompatibility, coating stability and the inability to effectively combat multiple drug-resistant bacteria. In this research, we developed an antibiofilm surface coating for medical catheters using biosynthesized silver nanoparticles (b-Cs-AgNPs) developed using leaves extract of Calliandra surinamensis. Various characterization techniques were employed to thoroughly characterize the synthesized b-Cs-AgNPs and c-AgNPs. b-Cs-AgNPs were compatible with human normal kidney cells and chicken embryos. It did not trigger any skin inflammatory response in in vivo rat model. b-Cs-AgNPs demonstrated potent zone of inhibition of 19.09 mm when subjected to the disc diffusion method in E. coli confirming strong antibacterial property. Different anti-bacterial assays including liquid growth curve, colony counting assay, biofilm formation assay supported the potent antimicrobial efficacy of b-Cs-AgNPs alone and when coated to medical grade catheters. Mechanistic studies reveal the presence of ferulic acid, that was important for the synthesis of b-AgNPs along with enhanced antibacterial effects of b-Cs-AgNPs compared to c-AgNPs, supported by molecular docking analysis. These results together demonstrated the effective role b-Cs-AgNPs in combating infections and mitigating biofilm formations, highlighting their need for further study in the field of biomedical applications.}, }
@article {pmid38744329, year = {2024}, author = {Kriswandini, IL and Sidarningsih, S and Hermanto, AC and Tyas, PR and Aljunaid, MA}, title = {The Influence of Streptococcus mutans Biofilm Formation in a Polymicrobial Environment (Streptococcus gordonii &amp; Porphyromonas gingivalis).}, journal = {European journal of dentistry}, volume = {18}, number = {4}, pages = {1085-1089}, pmid = {38744329}, issn = {1305-7456}, abstract = {OBJECTIVES: Biofilms play a vital role in the occurrence or worsening of an infectious disease. Streptococcus mutans is a bacterium with the ability to form biofilms that plays a key role in the development of infectious diseases such as dental caries. The formation of biofilms in S. mutans is mediated by quorum sensing. Inhibiting quorum sensing can be considered as one of the approaches to prevent caries. This study aims to investigate the ability of Streptococcus gordonii and Porphyromonas gingivalis bacteria to inhibit the formation of S. mutans biofilm.<br><br>MATERIALS AND METHODS: &#x2003;This research was conducted to analyze bacterial biofilm formation and metabolism. The bacteria used are S. mutans (serotype C), S. gordonii (ATCC 5165), and P. gingivalis (ATCC 33277). Biofilm formation was analyzed using the crystal violet assay. Bacterial metabolism was analyzed using the methylthiazol tetrazolium (MTT) assay.<br><br>RESULTS: &#x2003;The results of the crystal violet assay indicate a decrease in biofilm formation in S. mutans when in the presence of S. gordonii and S. mutans in the presence of P. gingivalis. The results of the MTT assay show no significant change in the bacterial metabolism of S. mutans in the presence of S. gordonii and S. mutans in the presence of P. gingivalis. However, S. mutans with the presence of S. gordonii and P. gingivalis show an increase in biofilm formation and bacterial metabolism.<br><br>CONCLUSION: &#x2003;S. gordonii and P. gingivalis are each capable of inhibiting the formation of S. mutans biofilm in a polymicrobial environment.}, }
@article {pmid38744202, year = {2024}, author = {Cheng, Y and Ding, J and Wan, J and Tang, L and Joseph, A and Usman, M and Zhu, N and Zhang, Y and Sun, H and Rene, ER and Lendvay, M and Li, Y}, title = {Improvement of biotic nitrate reduction in constructed photoautotrophic biofilm-soil microbial fuel cells.}, journal = {Journal of environmental management}, volume = {360}, number = {}, pages = {121066}, doi = {10.1016/j.jenvman.2024.121066}, pmid = {38744202}, issn = {1095-8630}, mesh = {*Biofilms ; *Bioelectric Energy Sources ; *Nitrates/metabolism ; *Soil/chemistry ; Soil Microbiology ; Electrodes ; Carbon/metabolism ; Oxidation-Reduction ; }, abstract = {The biotic nitrate reduction rate in freshwater ecosystems is typically constrained by the scarcity of carbon sources. In this study, 'two-chambers' - 'two-electrodes' photoautotrophic biofilm-soil microbial fuel cells (P-SMFC) was developed to accelerate nitrate reduction by activating in situ electron donors that originated from the soil organic carbon (SOC). The nitrate reduction rate of P-SMFC (0.1341 d[-1]) improved by ∼ 1.6 times on the 28th day compared to the control photoautotrophic biofilm. The relative abundance of electroactive bacterium increased in the P-SMFC and this bacterium contributed to obtain electrons from SOC. Biochar amendment decreased the resistivity of P-SMFC, increased the electron transferring efficiency, and mitigated anodic acidification, which continuously facilitated the thriving of putative electroactive bacterium and promoted current generation. The results from physiological and ecological tests revealed that the cathodic photoautotrophic biofilm produced more extracellular protein, increased the relative abundance of Lachnospiraceae, Magnetospirillaceae, Pseudomonadaceae, and Sphingomonadaceae, and improved the activity of nitrate reductase and ATPase. Correspondingly, P-SMFC in the presence of biochar achieved the highest reaction rate constant for nitrate reduction (kobs) (0.2092 d[-1]) which was 2.4 times higher than the control photoautotrophic biofilm. This study provided a new strategy to vitalize in situ carbon sources in paddy soil for nitrate reduction by the construction of P-SMFC.}, }
@article {pmid38744081, year = {2024}, author = {Müller, N and Kollert, M and Trampuz, A and Gonzalez Moreno, M}, title = {Efficacy of different bioactive glass S53P4 formulations in biofilm eradication and the impact of pH and osmotic pressure.}, journal = {Colloids and surfaces. B, Biointerfaces}, volume = {239}, number = {}, pages = {113940}, doi = {10.1016/j.colsurfb.2024.113940}, pmid = {38744081}, issn = {1873-4367}, mesh = {*Biofilms/drug effects ; *Glass/chemistry ; Hydrogen-Ion Concentration ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Microbial Sensitivity Tests ; *Staphylococcus epidermidis/drug effects/physiology ; *Methicillin-Resistant Staphylococcus aureus/drug effects/physiology ; *Vancomycin/pharmacology/chemistry ; *Osmotic Pressure/drug effects ; Drug Compounding ; }, abstract = {AIM: The challenging properties of biofilm-associated infections and the rise of multidrug-resistant bacteria are prompting the exploration of alternative treatment options. This study investigates the efficacy of different bioactive glass (BAG) formulations - alone or combined with vancomycin - to eradicate biofilm. Further, we study the influence of BAG on pH and osmotic pressure as important factors limiting bacterial growth.<br><br>METHOD: Different BAG S53P4 formulations were used for this study, including (a) powder (<45 &#x3bc;m), (b) granules (500-800&#x202f;&#xb5;m), (c) a cone-shaped scaffold and (d) two putty formulations containing granules with no powder (putty A) or with additional powder (putty B) bound together by a synthetic binder. Inert glass beads (1.0-1.3&#x202f;mm) were included as control. All formulations were tested in a concentration of 1750&#x202f;mg/ml in M&#xfc;ller-Hinton-Broth against methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus epidermidis (MRSE). Vancomycin was tested at the minimum-inhibitory concentration for each strain. Changes in pH and osmolality over time were assessed at 0&#x202f;h, 24&#x202f;h, 72&#x202f;h and 168&#x202f;h.<br><br>RESULTS: All tested BAG formulations showed antibiofilm activity against MRSA and MRSE. Powder and putty B were the most effective formulations suppressing biofilm leading to its complete eradication after up to 168&#x202f;h of co-incubation, followed by granules, scaffold and putty A. In general, MRSE appeared to be more susceptible to bioactive glass compared to MRSA. The addition of vancomycin had no substantial impact on biofilm eradication. We observed a positive correlation between a higher pH and higher antibiofilm activity.<br><br>CONCLUSIONS: BAG S53P4 has demonstrated efficient biofilm antibiofilm activity against MRSA and MRSE, especially in powder-containing formulations, resulting in complete eradication of biofilm. Our data indicate neither remarkable increase nor decrease in antimicrobial efficacy with addition of vancomycin. Moreover, high pH appears to have a direct antimicrobial impact; the role of high osmolality needs further investigation.}, }
@article {pmid38744077, year = {2024}, author = {Qu, L and Li, X and Zhou, J and Peng, X and Zhou, P and Zheng, H and Jiang, Z and Xie, Q}, title = {A novel acid-responsive polymer coating with antibacterial and antifouling properties for the prevention of biofilm-associated infections.}, journal = {Colloids and surfaces. B, Biointerfaces}, volume = {239}, number = {}, pages = {113939}, doi = {10.1016/j.colsurfb.2024.113939}, pmid = {38744077}, issn = {1873-4367}, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Escherichia coli/drug effects ; *Staphylococcus aureus/drug effects ; *Polymers/chemistry/pharmacology ; *Curcumin/pharmacology/chemistry ; Bacterial Adhesion/drug effects ; Coated Materials, Biocompatible/chemistry/pharmacology ; Animals ; Microbial Sensitivity Tests ; Boronic Acids/chemistry/pharmacology ; Surface Properties ; Humans ; Biofouling/prevention &amp; control ; Hydrogen-Ion Concentration ; }, abstract = {Chronic infections caused by the pathogenic biofilms on implantable medical devices pose an increasing challenge. To combat long-term biofilm-associated infections, we developed a novel dual-functional polymer coating with antibacterial and antifouling properties. The coating consists of N-vinylpyrrolidone (NVP) and 3-(acrylamido)phenylboronic acid (APBA) copolymer brushes, which bind to curcumin (Cur) as antibacterial molecules through acid-responsive boronate ester bonds. In this surface design, the hydrophilic poly (N-vinylpyrrolidone) (PVP) component improved antifouling performance and effectively prevented bacterial adhesion and aggregation during the initial phases. The poly (3-(acrylamido) phenylboronic acid) (PAPBA, abbreviated PB) component provided binding sites for Cur by forming acid-responsive boronate ester bonds. When fewer bacteria overcame the anti-adhesion barrier and colonized, the surface responded to the decreased microenvironmental pH by breaking the boronate ester bonds and releasing curcumin. This responsive mechanism enabled Cur to interfere with biofilm formation and provide a multilayer anti-biofilm protection system. The coating showed excellent antibacterial properties against Escherichia coli and Staphylococcus aureus, preventing biofilm formation for up to 7 days. The coating also inhibited protein adsorption and platelet adhesion significantly. This coating also exhibited high biocompatibility with animal erythrocytes and pre-osteoblasts. This research offers a promising approach for developing novel smart anti-biofilm coating materials.}, }
@article {pmid38743334, year = {2024}, author = {A, D and Zhang, Y and Huang, H and Pan, Y and Di, HJ and Yi, Y and Zhang, X and Yang, J}, title = {Unraveling the mechanism of interaction: accelerated phenanthrene degradation and rhizosphere biofilm/iron plaque formation influenced by phenolic root exudates.}, journal = {Environmental science and pollution research international}, volume = {31}, number = {24}, pages = {35853-35863}, pmid = {38743334}, issn = {1614-7499}, support = {2020B0202080002//Key Research and Development Project of Guangdong Province/ ; 2022A1515011319//Natural Science Foundation of Guangdong Province, China/ ; 202201011783//Technology Project of Guangzhou City, China/ ; 202208440274//Local Cooperation Project of China Scholarship Council/ ; }, mesh = {*Rhizosphere ; *Phenanthrenes/metabolism ; *Biofilms ; *Iron/metabolism ; *Biodegradation, Environmental ; *Plant Roots ; Phenols/metabolism ; Wetlands ; }, abstract = {Phenolic root exudates (PREs) secreted by wetland plants facilitate the accumulation of iron in the rhizosphere, potentially providing the essential active iron required for the generation of enzymes that degrade polycyclic aromatic hydrocarbon, thereby enhancing their biodegradation. However, the underlying mechanisms involved are yet to be elucidated. This study focuses on phenanthrene (PHE), a typical polycyclic aromatic hydrocarbon pollutant, utilizing representative PREs from wetland plants, including p-hydroxybenzoic, p-coumaric, caffeic, and ferulic acids. Using hydroponic experiments, 16S rRNA sequencing, and multiple characterization techniques, we aimed to elucidate the interaction mechanism between the accelerated degradation of PHE and the formation of rhizosphere biofilm/iron plaque influenced by PREs. Although all four types of PREs altered the biofilm composition and promoted the formation of iron plaque on the root surface, only caffeic acid, possessing a similar structure to the intermediate metabolite of PHE (catechol), could accelerate the PHE degradation rate. Caffeic acid, notable for its catechol structure, plays a significant role in enhancing PHE degradation through two main mechanisms: (a) it directly boosts PHE co-metabolism by fostering the growth of PHE-degrading bacteria, specifically Burkholderiaceae, and by facilitating the production of the key metabolic enzyme catechol 1,2-dioxygenase (C12O) and (b) it indirectly supports PHE biodegradation by promoting iron plaque formation on root surfaces, thereby enriching free iron for efficient microbial synthesis of C12O, a crucial factor in PHE decomposition.}, }
@article {pmid38743043, year = {2024}, author = {Lopes, N and Pereira, RB and Correia, A and Vilanova, M and Cerca, N and França, A}, title = {Deletion of codY impairs Staphylococcus epidermidis biofilm formation, generation of viable but non-culturable cells and stimulates cytokine production in human macrophages.}, journal = {Journal of medical microbiology}, volume = {73}, number = {5}, pages = {}, doi = {10.1099/jmm.0.001837}, pmid = {38743043}, issn = {1473-5644}, mesh = {*Staphylococcus epidermidis/genetics/physiology ; *Biofilms/growth &amp; development ; Humans ; *Macrophages/microbiology/immunology ; *Cytokines/metabolism/genetics ; *Bacterial Proteins/genetics/metabolism ; Anti-Bacterial Agents/pharmacology ; Staphylococcal Infections/microbiology ; Gene Deletion ; Virulence ; Microbial Viability ; }, abstract = {Introduction. Staphylococcus epidermidis biofilms are one of the major causes of bloodstream infections related to the use of medical devices. The diagnosis of these infections is challenging, delaying their treatment and resulting in increased morbidity and mortality rates. As such, it is urgent to characterize the mechanisms employed by this bacterium to endure antibiotic treatments and the response of the host immune system, to develop more effective therapeutic strategies. In several bacterial species, the gene codY was shown to encode a protein that regulates the expression of genes involved in biofilm formation and immune evasion. Additionally, in a previous study, our group generated evidence indicating that codY is involved in the emergence of viable but non-culturable (VBNC) cells in S. epidermidis.Gap statement/Hypothesis. As such, we hypothesized that the gene codY has have an important role in this bacterium virulence.Aim. This study aimed to assess, for the first time, the impact of the deletion of the gene codY in S. epidermidis virulence, namely, in antibiotic susceptibility, biofilm formation, VBNC state emergence and in vitro host immune system response.Methodology. Using an allelic replacement strategy, we constructed and then characterized an S. epidermidis strain lacking codY, in regards to biofilm and VBNC cell formation, susceptibility to antibiotics as well as their role in the interaction with human blood and plasma. Additionally, we investigate whether the codY gene can impact the activation of innate immune cells by evaluating the production of both pro- and anti-inflammatory cytokines by THP-1 macrophages.Results. We demonstrated that the deletion of the gene codY resulted in biofilms with less c.f.u. counts and fewer VBNC cells. Furthermore, we show that although WT and mutant cells were similarly internalized in vitro by human macrophages, a stronger cytokine response was elicited by the mutant in a toll-like receptor 4-dependent manner.Conclusion. Our results indicate that codY contributes to S. epidermidis virulence, which in turn may have an impact on our ability to manage the biofilm-associated infections caused by this bacterium.}, }
@article {pmid38741276, year = {2024}, author = {Ni, L and Shen, R and Luo, H and Li, X and Zhang, X and Huang, L and Deng, Y and Liao, X and Wu, Y and Duan, C and Xie, X}, title = {GlmS plays a key role in the virulence factor expression and biofilm formation ability of Staphylococcus aureus promoted by advanced glycation end products.}, journal = {Virulence}, volume = {15}, number = {1}, pages = {2352476}, pmid = {38741276}, issn = {2150-5608}, support = {82002203]//National Natural Science Foundation of China/ ; 2023A1515010089//Basic and Applied Basic Research Foundation of Guangdong Province/ ; }, mesh = {Humans ; *Bacterial Proteins/genetics/metabolism ; *Biofilms/growth &amp; development ; *Gene Expression Regulation, Bacterial ; *Glycation End Products, Advanced/metabolism ; Sigma Factor/genetics/metabolism ; Staphylococcal Infections/microbiology ; *Staphylococcus aureus/genetics/pathogenicity ; *Virulence Factors/genetics ; }, abstract = {Staphylococcus aureus (S. aureus) is well known for its biofilm formation ability and is responsible for serious, chronic refractory infections worldwide. We previously demonstrated that advanced glycation end products (AGEs), a hallmark of chronic hyperglycaemia in diabetic tissues, enhanced biofilm formation by promoting eDNA release via sigB upregulation in S. aureus, contributing to the high morbidity and mortality of patients presenting a diabetic foot ulcer infection. However, the exact regulatory network has not been completely described. Here, we used pull-down assay and LC-MS/MS to identify the GlmS as a candidate regulator of sigB in S. aureus stimulated by AGEs. Dual-luciferase assays and electrophoretic mobility shift assays (EMSAs) revealed that GlmS directly upregulated the transcriptional activity of sigB. We constructed NCTC 8325 ∆glmS for further validation. qRT-PCR analysis revealed that AGEs promoted both glmS and sigB expression in the NCTC 8325 strain but had no effect on NCTC 8325 ∆glmS. NCTC 8325 ∆glmS showed a significant attenuation in biofilm formation and virulence factor expression, accompanied by a decrease in sigB expression, even under AGE stimulation. All of the changes, including pigment deficiency, decreased haemolysis ability, downregulation of hla and hld expression, and less and sparser biofilms, indicated that sigB and biofilm formation ability no longer responded to AGEs in NCTC 8325 ∆glmS. Our data extend the understanding of GlmS in the global regulatory network of S. aureus and demonstrate a new mechanism by which AGEs can upregulate GlmS, which directly regulates sigB and plays a significant role in mediating biofilm formation and virulence factor expression.}, }
@article {pmid38741081, year = {2024}, author = {Haude, S and Matthes, R and Pitchika, V and Holtfreter, B and Schlüter, R and Gerling, T and Kocher, T and Jablonowski, L}, title = {In-vitro biofilm removal from TiUnite® implant surface with an air polishing and two different plasma devices.}, journal = {BMC oral health}, volume = {24}, number = {1}, pages = {558}, pmid = {38741081}, issn = {1472-6831}, mesh = {*Biofilms/drug effects ; *Titanium/chemistry ; *Plasma Gases ; *Surface Properties ; *Dental Implants/microbiology ; Dental Polishing/methods ; Glycine ; Humans ; In Vitro Techniques ; Microscopy, Electron, Scanning ; Nickel ; }, abstract = {BACKGROUND: We investigated the efficacy of two different cold atmospheric pressure jet plasma devices (CAP09 and CAPmed) and an air polishing device with glycine powder (AP) either applied as monotherapies or combined therapies (AP + CAP09; AP + CAPmed), in microbial biofilm removal from discs with anodised titanium surface.<br><br>METHODS: Discs covered with 7-day-old microbial biofilm were treated either with CAP09, CAPmed, AP, AP&#x2009;+&#x2009;CAP09 or AP&#x2009;+&#x2009;CAPmed and compared with negative and positive controls. Biofilm removal was assessed with flourescence and electron microscopy immediately after treatment and after 5 days of reincubation of the treated discs.<br><br>RESULTS: Treatment with CAP09 or CAPmed did not lead to an effective biofilm removal, whereas treatment with AP detached the complete biofilm, which however regrew to baseline magnitude after 5 days of reincubation. Both combination therapies (AP&#x2009;+&#x2009;CAP09 and AP&#x2009;+&#x2009;CAPmed) achieved a complete biofilm removal immediately after cleaning. However, biofilm regrew after 5 days on 50% of the discs treated with the combination therapy.<br><br>CONCLUSION: AP treatment alone can remove gross biofilm immediately from anodised titanium surfaces. However, it did not impede regrowth after 5 days, because microorganisms were probably hidden in holes and troughs, from which they could regrow, and which were inaccessible to AP. The combination of AP and plasma treatment probably removed or inactivated microorganisms also from these hard to access spots. These results were independent of the choice of plasma device.}, }
@article {pmid38740670, year = {2024}, author = {Ribeiro, NS and da Rosa, DF and Xavier, MA and Dos Reis, SV and Beys-da-Silva, WO and Santi, L and Bizarro, CV and Dalberto, PF and Basso, LA and Macedo, AJ}, title = {Unveiling antibiofilm potential: proteins from Priestia sp. targeting Staphylococcus aureus biofilm formation.}, journal = {Antonie van Leeuwenhoek}, volume = {117}, number = {1}, pages = {78}, pmid = {38740670}, issn = {1572-9699}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Staphylococcus aureus/drug effects/physiology ; *Bacterial Proteins/genetics/metabolism ; *Anti-Bacterial Agents/pharmacology ; Animals ; Microbial Sensitivity Tests ; Brazil ; Porifera/microbiology ; }, abstract = {Staphylococcus aureus is the etiologic agent of many nosocomial infections, and its biofilm is frequently isolated from medical devices. Moreover, the dissemination of multidrug-resistant (MDR) strains from this pathogen, such as methicillin-resistant S. aureus (MRSA) strains, is a worldwide public health issue. The inhibition of biofilm formation can be used as a strategy to weaken bacterial resistance. Taking that into account, we analysed the ability of marine sponge-associated bacteria to produce antibiofilm molecules, and we found that marine Priestia sp., isolated from marine sponge Scopalina sp. collected on the Brazilian coast, secretes proteins that impair biofilm development from S. aureus. Partially purified proteins (PPP) secreted after 24 hours of bacterial growth promoted a 92% biofilm mass reduction and 4.0 µg/dL was the minimum concentration to significantly inhibit biofilm formation. This reduction was visually confirmed by light microscopy and Scanning Electron Microscopy (SEM). Furthermore, biochemical assays showed that the antibiofilm activity of PPP was reduced by ethylenediaminetetraacetic acid (EDTA) and 1,10 phenanthroline (PHEN), while it was stimulated by zinc ions, suggesting an active metallopeptidase in PPP. This result agrees with mass spectrometry (MS) identification, which indicated the presence of a metallopeptidase from the M28 family. Additionally, whole-genome sequencing analysis of Priestia sp. shows that gene ywad, a metallopeptidase-encoding gene, was present. Therefore, the results presented herein indicate that PPP secreted by the marine Priestia sp. can be explored as a potential antibiofilm agent and help to treat chronic infections.}, }
@article {pmid38740038, year = {2024}, author = {Xu, Y and Luo, W and Deng, H and Hu, X and Zhang, J and Wang, Y}, title = {Robust antibacterial activity of rare-earth ions on planktonic and biofilm bacteria.}, journal = {Biomedical materials (Bristol, England)}, volume = {19}, number = {4}, pages = {}, doi = {10.1088/1748-605X/ad4aa9}, pmid = {38740038}, issn = {1748-605X}, mesh = {*Metals, Rare Earth/chemistry/pharmacology ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Biofilms/drug effects ; *Plankton/drug effects ; *Microbial Sensitivity Tests ; *Pseudomonas aeruginosa/drug effects ; *Ions ; Humans ; Staphylococcus aureus/drug effects ; Animals ; Norfloxacin/pharmacology/chemistry ; }, abstract = {Bacterial infections pose a serious threat to human health, with emerging antibiotic resistance, necessitating the development of new antibacterial agents. Cu[2+]and Ag[+]are widely recognized antibacterial agents with a low propensity for inducing bacterial resistance; however, their considerable cytotoxicity constrains their clinical applications. Rare-earth ions, owing to their unique electronic layer structure, hold promise as promising alternatives. However, their antibacterial efficacy and biocompatibility relative to conventional antibacterial agents remain underexplored, and the variations in activity across different rare-earth ions remain unclear. Here, we systematically evaluate the antibacterial activity of five rare-earth ions (Yb[3+], Gd[3+], Sm[3+], Tb[3+], and La[3+]) againstStaphylococcus aureusandPseudomonas aeruginosa, benchmarked against well-established antibacterial agents (Cu[2+], Ag[+]) and the antibiotic norfloxacin. Cytotoxicity is also assessed via live/dead staining of fibroblasts after 24 h rare-earth ion exposure. Our findings reveal that rare-earth ions require higher concentrations to match the antibacterial effects of traditional agents but offer the advantage of significantly lower cytotoxicity. In particular, Gd[3+]demonstrates potent bactericidal efficacy against both planktonic and biofilm bacteria, while maintaining the lowest cytotoxicity toward mammalian cells. Moreover, the tested rare-earth ions also exhibited excellent antifungal activity againstCandida albicans. This study provides a critical empirical framework to guide the selection of rare-earth ions for biomedical applications, offering a strategic direction for the development of novel antimicrobial agents.}, }
@article {pmid38739655, year = {2024}, author = {Xiong, L and Pereira De Sa, N and Zarnowski, R and Huang, MY and Mota Fernandes, C and Lanni, F and Andes, DR and Del Poeta, M and Mitchell, AP}, title = {Biofilm-associated metabolism via ERG251 in Candida albicans.}, journal = {PLoS pathogens}, volume = {20}, number = {5}, pages = {e1012225}, pmid = {38739655}, issn = {1553-7374}, support = {R01 AI073289/AI/NIAID NIH HHS/United States ; R01 AI116420/AI/NIAID NIH HHS/United States ; R01 AI125770/AI/NIAID NIH HHS/United States ; R01 AI146103/AI/NIAID NIH HHS/United States ; }, mesh = {*Biofilms/growth &amp; development ; *Candida albicans/metabolism/genetics/physiology ; *Fungal Proteins/metabolism/genetics ; Animals ; *Candidiasis/microbiology/metabolism ; Hyphae/metabolism ; Mice ; Gene Expression Regulation, Fungal ; Ergosterol/metabolism ; Transcription Factors/metabolism/genetics ; Mutation ; }, abstract = {Biofilm formation by the fungal pathogen Candida albicans is the basis for its ability to infect medical devices. The metabolic gene ERG251 has been identified as a target of biofilm transcriptional regulator Efg1, and here we report that ERG251 is required for biofilm formation but not conventional free-living planktonic growth. An erg251Δ/Δ mutation impairs biofilm formation in vitro and in an in vivo catheter infection model. In both in vitro and in vivo biofilm contexts, cell number is reduced and hyphal length is limited. To determine whether the mutant defect is in growth or some other aspect of biofilm development, we examined planktonic cell features in a biofilm-like environment, which was approximated with sealed unshaken cultures. Under those conditions, the erg251Δ/Δ mutation causes defects in growth and hyphal extension. Overexpression in the erg251Δ/Δ mutant of the paralog ERG25, which is normally expressed more weakly than ERG251, partially improves biofilm formation and biofilm hyphal content, as well as growth and hyphal extension in a biofilm-like environment. GC-MS analysis shows that the erg251Δ/Δ mutation causes a defect in ergosterol accumulation when cells are cultivated under biofilm-like conditions, but not under conventional planktonic conditions. Overexpression of ERG25 in the erg251Δ/Δ mutant causes some increase in ergosterol levels. Finally, the hypersensitivity of efg1Δ/Δ mutants to the ergosterol inhibitor fluconazole is reversed by ERG251 overexpression, arguing that reduced ERG251 expression contributes to this efg1Δ/Δ phenotype. Our results indicate that ERG251 is required for biofilm formation because its high expression levels are necessary for ergosterol synthesis in a biofilm-like environment.}, }
@article {pmid38739212, year = {2024}, author = {Datta, S and Singh, V and Nag, S and Roy, DN}, title = {Marine-Derived Cytosine Arabinoside (Ara-C) Inhibits Biofilm Formation by Inhibiting PEL Operon Proteins (Pel A and Pel B) of Pseudomonas aeruginosa: An In Silico Approach.}, journal = {Molecular biotechnology}, volume = {}, number = {}, pages = {}, pmid = {38739212}, issn = {1559-0305}, abstract = {Pseudomonas aeruginosa (P. aeruginosa) is a gram-negative biofilm-forming opportunistic human pathogen whose vital mechanism is biofilm formation for better survival. PelA and PelB proteins of the PEL operon are essential for bacterial-synthesized pellicle polysaccharide (PEL), which is a vital structural component of the biofilm. It helps in adherence of biofilm on the surface and maintenance of cell-to-cell interactions and with other matrix components. Here, in-silico molecular docking and simulation studies were performed against PelA and PelB using ten natural bioactive compounds, individually [podocarpic acids, ferruginol, scopadulcic acid B, pisiferic acid, metachromin A, Cytarabine (cytosine arabinoside; Ara-C), ursolic acid, oleanolic acid, maslinic acid, and betulinic acid], those have already been established as anti-infectious compounds. The results obtained from AutoDock and Glide-Schordinger stated that a marine-derived cytosine arabinoside (Ara-C) among the ten compounds binds active sites of PelA and PelB, exhibiting strong binding affinity [Trp224 (hydrogen), Ser219 (polar), Val234 (hydrophobic) for PelA; Leu365 and Glu389 (hydrogen), Gln366 (polar) for PelB] with high negative binding energy - 5.518 kcal/mol and - 6.056 kcal/mol, respectively. The molecular dynamic and simulation studies for 100 ns showed the MMGBSA binding energy scores are - 16.4 kcal/mol (Ara-C with PelA), and - 22.25 kcal/mol (Ara-C with PelB). Further, ADME/T studies indicate the IC50 values of AraC are 6.10 mM for PelA and 18.78 mM for PelB, which is a comparatively very low dose. The zero violation of Lipinski's Rule of Five further established that Ara-C is a good candidate for drug development. Thus, Ara-C could be considered a potent anti-biofilm compound against PEL operon-dependent biofilm formation of P. aeruginosa.}, }
@article {pmid38738757, year = {2024}, author = {Quni, S and Zhang, Y and Liu, L and Liu, M and Zhang, L and You, J and Cui, J and Liu, X and Wang, H and Li, D and Zhou, Y}, title = {NF-κB-Signaling-Targeted Immunomodulatory Nanoparticle with Photothermal and Quorum-Sensing Inhibition Effects for Efficient Healing of Biofilm-Infected Wounds.}, journal = {ACS applied materials &amp; interfaces}, volume = {16}, number = {20}, pages = {25757-25772}, doi = {10.1021/acsami.4c03142}, pmid = {38738757}, issn = {1944-8252}, mesh = {Animals ; Humans ; Mice ; *Anti-Bacterial Agents/chemistry/pharmacology ; *Biofilms/drug effects ; Flavanones/chemistry/pharmacology ; Immunomodulating Agents/chemistry/pharmacology ; Indoles/chemistry/pharmacology ; Macrophages/drug effects/metabolism ; *Nanoparticles/chemistry/therapeutic use ; *NF-kappa B/metabolism ; Polymers/chemistry/pharmacology ; *Quorum Sensing/drug effects ; RAW 264.7 Cells ; Signal Transduction/drug effects ; Staphylococcus aureus/drug effects/physiology ; *Wound Healing/drug effects ; Wound Infection/drug therapy ; }, abstract = {The development of therapeutics with high antimicrobial activity and immunomodulatory effects is urgently needed for the treatment of infected wounds due to the increasing danger posed by recalcitrant-infected wounds. In this study, we developed light-controlled antibacterial, photothermal, and immunomodulatory biomimetic N/hPDA@M nanoparticles (NPs). This nanoplatform was developed by loading flavonoid naringenin onto hollow mesoporous polydopamine NPs in a π-π-stacked configuration and encasing them with macrophage membranes. First, our N/hPDA@M NPs efficiently neutralized inflammatory factors present within the wound microenvironment by the integration of macrophage membranes. Afterward, the N/hPDA@M NPs effectively dismantled bacterial biofilms through a combination of the photothermal properties of PDA and the quorum sensing inhibitory effects of naringenin. It is worth noting that N/hPDA@M NPs near-infrared-enhanced release of naringenin exhibited specificity toward the NF-κB-signaling pathway, effectively mitigating the inflammatory response. This innovative design not only conferred remarkable antibacterial properties upon the N/hPDA@M NPs but also endowed them with the capacity to modulate inflammatory responses, curbing excessive inflammation and steering macrophage polarization toward the M2 phenotype. As a result, this multifaceted approach significantly contributes to expediting the healing process of infected skin wounds.}, }
@article {pmid38737754, year = {2024}, author = {Tang, Y and Zhang, Z and Tao, C and Wang, X}, title = {The mechanism of biofilm detachment in porous medium under flow field.}, journal = {Biomicrofluidics}, volume = {18}, number = {3}, pages = {034103}, pmid = {38737754}, issn = {1932-1058}, abstract = {Biofilms are communities formed by bacteria adhering to surfaces, widely present in porous medium, and their growth can lead to clogging. Our experiment finds that under certain flow conditions, biofilms detach in pores and form a dynamically changing flow path. We define detachment that occurs far from the boundary of the flow path (with a distance greater than 200 μm) as internal detachment and detachment that occurs at the boundary of the flow path as external detachment. To understand the mechanism of biofilm detachment, we study the detachment behaviors of the Bacillus subtilis biofilm in a porous medium in a microfluidic device, where Bacillus subtilis strain is triple fluorescent labeled, which can represent three main phenotypes during the biofilm formation: motile cells, matrix-producing cells, and spores. We find that slow small-scale internal detachment occurs in regions with very few motile cells and matrix-producing cells, and bacterial movement in these areas is disordered. The increase in the number of matrix-producing cells induces clogging, and after clogging, the rapid detachment of the bulk internal biofilm occurs due to the increased pressure difference at the inlet and outlet. When both internal and external detachments occur simultaneously, the number of matrix-producing cells in the internal detachment area is 2.5 times that in the external detachment area. The results indicate that biofilm detachment occurs in areas with fewer matrix-producing cells, as matrix-producing cells can help resist detachment by secreting extracellular polymeric substances (EPSs).}, }
@article {pmid38736937, year = {2024}, author = {Bakalakos, M and Ampadiotaki, MM and Vlachos, C and Sipsas, N and Pneumaticos, S and Vlamis, J}, title = {Molecular Mechanisms of Biofilm Formation on Orthopaedic Implants: Review of the Literature.}, journal = {Maedica}, volume = {19}, number = {1}, pages = {129-136}, pmid = {38736937}, issn = {1841-9038}, abstract = {Orthopaedic implant-associated infections (OIAIs) is one of the most catastrophic complications following joint arthroplasty or fracture fixation. Given the increasing number of orthopaedic implants which are used annually, periprosthetic infections emerge as a global problem. Their diagnosis and consequent therapeutic management remain challenging for clinicians. Biofilm formation is a complex and only partially understood process that has not been extensively studied. Understanding the underlying mechanisms involved in biofilm formation is crucial in the amelioration of both diagnosis and therapeutic management of OIAIs. We performed a literature review of the molecular mechanisms of biofilm formation and discussed the four most common and thoroughly researched microbes of biofilm-related OIAIs.}, }
@article {pmid38736020, year = {2024}, author = {Pozelli Macedo, MJ and Xavier-Queiroz, M and Dabul, ANG and Ricomini-Filho, AP and Hamann, PRV and Polikarpov, I}, title = {Biochemical properties of a Flavobacterium johnsoniae dextranase and its biotechnological potential for Streptococcus mutans biofilm degradation.}, journal = {World journal of microbiology &amp; biotechnology}, volume = {40}, number = {7}, pages = {201}, pmid = {38736020}, issn = {1573-0972}, support = {2023/10037-0//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado de S&#xe3;o Paulo/ ; 2023/10037-0//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado de S&#xe3;o Paulo/ ; 2021/08780-1//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado de S&#xe3;o Paulo/ ; 306852/2021-7//Conselho Nacional de Desenvolvimento Cient&#xed;fico e Tecnol&#xf3;gico/ ; }, mesh = {*Biofilms/growth &amp; development ; *Dextranase/metabolism/genetics ; *Flavobacterium/enzymology/genetics ; *Streptococcus mutans/enzymology/genetics ; *Glycoside Hydrolases/metabolism/genetics ; Recombinant Proteins/metabolism/genetics ; Bacterial Proteins/metabolism/genetics ; Hydrolysis ; Biotechnology/methods ; }, abstract = {Cariogenic biofilms have a matrix rich in exopolysaccharides (EPS), mutans and dextrans, that contribute to caries development. Although several physical and chemical treatments can be employed to remove oral biofilms, those are only partly efficient and use of biofilm-degrading enzymes represents an exciting opportunity to improve the performance of oral hygiene products. In the present study, a member of a glycosyl hydrolase family 66 from Flavobacterium johnsoniae (FjGH66) was heterologously expressed and biochemically characterized. The recombinant FjGH66 showed a hydrolytic activity against an early EPS-containing S. mutans biofilm, and, when associated with a α-(1,3)-glucosyl hydrolase (mutanase) from GH87 family, displayed outstanding performance, removing more than 80% of the plate-adhered biofilm. The mixture containing FjGH66 and Prevotella melaninogenica GH87 α-1,3-mutanase was added to a commercial mouthwash liquid to synergistically remove the biofilm. Dental floss and polyethylene disks coated with biofilm-degrading enzymes also degraded plate-adhered biofilm with a high efficiency. The results presented in this study might be valuable for future development of novel oral hygiene products.}, }
@article {pmid38735452, year = {2024}, author = {Pandey, P and Rao, L and Shekhar, BR and Das, DK and Vavilala, SL}, title = {Molecular insights into flavone-mediated quorum sensing interference: A novel strategy against Serratiamarcescens biofilm-induced antibiotic resistance".}, journal = {Chemico-biological interactions}, volume = {396}, number = {}, pages = {111027}, doi = {10.1016/j.cbi.2024.111027}, pmid = {38735452}, issn = {1872-7786}, mesh = {*Biofilms/drug effects ; *Quorum Sensing/drug effects ; *Flavones/pharmacology/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Molecular Docking Simulation ; *Microbial Sensitivity Tests ; Molecular Dynamics Simulation ; Reactive Oxygen Species/metabolism ; Drug Resistance, Microbial/drug effects ; Virulence Factors/metabolism ; Bacterial Proteins/metabolism ; }, abstract = {Antibiotic resistance poses a significant challenge in modern medicine, urging the exploration of innovative approaches to combat bacterial infections. Biofilms, complex bacterial communities encased in a protective matrix, contribute to resistance by impeding antibiotic efficacy and promoting genetic exchange. Understanding biofilm dynamics is crucial for developing effective antimicrobial therapies against antibiotic resistance. This study explores the potential of flavone to combat biofilm-induced antibiotic resistance by employing in-vitro biochemical, cell biology, and Insilico (MD simulation), approaches. Flavone exhibited potent antibacterial effects with a low minimum inhibitory concentration by inducing intracellular reactive oxygen species. Flavones further inhibited the formation of biofilms by 50-60 % and disrupted the pre-formed biofilms by reducing the extracellular polysaccharide substance protective layer formed on the biofilm by 80 %. Quorum sensing (QS) plays a crucial role in bacterial pathogenicity and flavone significantly attenuated the production of QS-induced virulence factors like urease, protease, lipase, hemolysin and prodigiosin pigment in a dose-dependent manner. Further Insilico molecular docking studies along with molecular dynamic simulations run for 100 ns proved the stable binding affinity of flavone with QS-specific proteins which are crucial for biofilm formation. This study demonstrates the therapeutic potential of flavone to target QS-signaling pathway to combat S.marcescens biofilms.}, }
@article {pmid38735084, year = {2024}, author = {Long, J and Yang, C and Liu, J and Ma, C and Jiao, M and Hu, H and Xiong, J and Zhang, Y and Wei, W and Yang, H and He, Y and Zhu, M and Yu, Y and Fu, L and Chen, H}, title = {Tannic acid inhibits Escherichia coli biofilm formation and underlying molecular mechanisms: Biofilm regulator CsgD.}, journal = {Biomedicine &amp; pharmacotherapy = Biomedecine &amp; pharmacotherapie}, volume = {175}, number = {}, pages = {116716}, doi = {10.1016/j.biopha.2024.116716}, pmid = {38735084}, issn = {1950-6007}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Tannins/pharmacology ; *Escherichia coli/drug effects ; *Escherichia coli Proteins/metabolism/genetics ; *Gene Expression Regulation, Bacterial/drug effects ; Anti-Bacterial Agents/pharmacology ; Trans-Activators ; }, abstract = {Biofilms often engender persistent infections, heightened antibiotic resistance, and the recurrence of infections. Therefor, infections related to bacterial biofilms are often chronic and pose challenges in terms of treatment. The main transcription regulatory factor, CsgD, activates csgABC-encoded curli to participate in the composition of extracellular matrix, which is an important skeleton for biofilm development in enterobacteriaceae. In our previous study, a wide range of natural bioactive compounds that exhibit strong affinity to CsgD were screened and identified via molecular docking. Tannic acid (TA) was subsequently chosen, based on its potent biofilm inhibition effect as observed in crystal violet staining. Therefore, the aim of this study was to investigate the specific effects of TA on the biofilm formation of clinically isolated Escherichia coli (E. coli). Results demonstrated a significant inhibition of E. coli Ec032 biofilm formation by TA, while not substantially affecting the biofilm of the ΔcsgD strain. Moreover, deletion of the csgD gene led to a reduction in Ec032 biofilm formation, alongside diminished bacterial motility and curli synthesis inhibition. Transcriptomic analysis and RT-qPCR revealed that TA repressed genes associated with the csg operon and other biofilm-related genes. In conclusion, our results suggest that CsgD is one of the key targets for TA to inhibit E. coli biofilm formation. This work preliminarily elucidates the molecular mechanisms of TA inhibiting E. coli biofilm formation, which could provide a lead structure for the development of future antibiofilm drugs.}, }
@article {pmid38734101, year = {2024}, author = {Sun, L and Yue, X and Zhang, G and Wang, A}, title = {A pilot-scale anoxic-anaerobic-anoxic-oxic combined with moving bed biofilm reactor system for advanced treatment of rural wastewater.}, journal = {The Science of the total environment}, volume = {933}, number = {}, pages = {173074}, doi = {10.1016/j.scitotenv.2024.173074}, pmid = {38734101}, issn = {1879-1026}, mesh = {*Bioreactors ; *Waste Disposal, Fluid/methods ; *Wastewater/microbiology ; *Biofilms ; Anaerobiosis ; Pilot Projects ; Nitrogen/analysis ; Phosphorus/analysis ; Water Pollutants, Chemical/analysis ; }, abstract = {Rural domestic poses a significant challenge to treatment technologies due to significant fluctuations in both water quality, particularly in terms of carbon concentration, and quantity. Conventional biological technology, such as anaerobic-anoxic-oxic (A[2]O) systems, is inefficient. In this work, a continuous pilot-scale anoxic-anaerobic-anoxic-oxic (A[3]O) reactor with a moving bed biofilm reactor (MBBR) system was constructed and optimized to improve the treatment efficiency of rural domestic wastewater. The sludge return ratio, volume ratio of the oxic-to-anoxic zone (Voxi/Vano), step-feeding and hydraulic retention time (HRT) at low temperature were considered the main parameters for optimization. Microbial analysis was performed on both the mixed liquor and carrier of the A3O-MBBR system under initial and post-optimized conditions. The results indicated that the A[3]O-MBBR improved the treatment efficiency of rural domestic wastewater, especially for total phosphorus (TP), which increased by 20 % compared with that of the A[2]O-MBR. In addition, the removal efficiencies of nitrogen and phosphorus were further optimized, and the average concentrations of total nitrogen (TN) and TP in the effluent reached 2.46 and 0.364 mg/L, respectively, at a sludge reflux ratio of 100 or 150 %, Voxi/Vano =200 %, step-feeding of 0.5Q/0.5Q (anaerobic/anoxic) and HRT of 15 h at low temperature in the A[3]O-MBBR, which met standard A of GB18918-2002, China (TN < 15 mg/L, TP < 0.5 mg/L). The average rate of attaining the standard increased by 58.63 % (post optimization). The microbial analysis showed an increase in species diversity and richness after the parameters were optimized. Moreover, compared to the microbial community structure before optimization, the post-optimization exhibited a more stable microbial structure with a significant enrichment of functional bacteria. Defluviimonas, Novosphingobium and Bifidobacterium, considered as the dominant nitrification or denitrifying bacteria, were enriched in the suspended sludge of the MBBR reactor, which the relative abundance increased by 3.11 %, 3.84 %, and 3.24 %, respectively. Further analysis of the microbial community in the carrier revealed that the abundance of Nitrospira and the denitrifying bacteria carried by the carrier were much greater than those in the suspended sludge. Consequently, the microorganism cooperation between suspended sludge and biofilm might be responsible for the improved performance of the optimized A[3]O-MBBR.}, }
@article {pmid38732269, year = {2024}, author = {Di Pietro, M and Filardo, S and Mattioli, R and Bozzuto, G and Raponi, G and Mosca, L and Sessa, R}, title = {Anti-Biofilm Activity of Oleacein and Oleocanthal from Extra-Virgin Olive Oil toward Pseudomonas aeruginosa.}, journal = {International journal of molecular sciences}, volume = {25}, number = {9}, pages = {}, pmid = {38732269}, issn = {1422-0067}, support = {RP12117A7B4D7EA2//Sapienza University of Rome/ ; RM120172A35E81B1//Sapienza University of Rome/ ; RM12117A439CD073//Sapienza University of Rome/ ; FSE REACT-EU Action IV.6//Ministero dell'Istruzione e del Merito/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Pseudomonas aeruginosa/drug effects ; *Olive Oil/chemistry/pharmacology ; *Cyclopentane Monoterpenes ; *Phenols/pharmacology/chemistry ; *Aldehydes/pharmacology/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; Humans ; Microbial Sensitivity Tests ; Pseudomonas Infections/drug therapy/microbiology ; Bacterial Adhesion/drug effects ; }, abstract = {New antimicrobial molecules effective against Pseudomonas aeruginosa, known as an antibiotic-resistant "high-priority pathogen", are urgently required because of its ability to develop biofilms related to healthcare-acquired infections. In this study, for the first time, the anti-biofilm and anti-virulence activities of a polyphenolic extract of extra-virgin olive oil as well as purified oleocanthal and oleacein, toward P. aeruginosa clinical isolates were investigated. The main result of our study was the anti-virulence activity of the mixture of oleacein and oleocanthal toward multidrug-resistant and intermediately resistant strains of P. aeruginosa isolated from patients with ventilator-associated pneumonia or surgical site infection. Specifically, the mixture of oleacein (2.5 mM)/oleocanthal (2.5 mM) significantly inhibited biofilm formation, alginate and pyocyanin production, and motility in both P. aeruginosa strains (p < 0.05); scanning electron microscopy analysis further evidenced its ability to inhibit bacterial cell adhesion as well as the production of the extracellular matrix. In conclusion, our results suggest the potential application of the oleacein/oleocanthal mixture in the management of healthcare-associated P. aeruginosa infections, particularly in the era of increasing antimicrobial resistance.}, }
@article {pmid38731305, year = {2024}, author = {Yi, L and Fan, H and Yuan, S and Li, R and Wang, H and Quan, Y and Zhang, H and Wang, Y and Wang, Y}, title = {Antimicrobial Resistance and Biofilm Formation of Bordetella bronchiseptica in Central China, with Evidence of a Rare Heteroresistance Strain to Gentamicin.}, journal = {Animals : an open access journal from MDPI}, volume = {14}, number = {9}, pages = {}, pmid = {38731305}, issn = {2076-2615}, support = {32172852//National Natural Science Foundation of China/ ; 222300420005//Excellent Youth Foundation of Henan Scientific Committee/ ; 232102110095//Henan Provincial Science and Technology Research Project/ ; 24IRTSTHN033//Program for Innovative Research Team (in Science and Technology) in University of Henan Province/ ; }, abstract = {Bordetella bronchiseptica is a significant contributor to respiratory disease in pigs, leading to substantial economic losses in the swine industry worldwide. We isolated 52 B. bronchiseptica strains from 542 samples collected from pigs with atrophic rhinitis and bronchopneumonia in central China. Multi-locus sequence typing identified two prevalent sequence types: ST6 (69.23%) and ST7 (30.77%). PCR-based detection of seven virulence genes (fhaB, prn, cyaA, dnt, bteA, fla, and bfrZ) revealed that six of these genes were present in over 90% of the isolates, with bfrZ being the exception at 59.62%. Antimicrobial susceptibility testing, performed using the K-B method, demonstrated high sensitivity to enrofloxacin, polymyxin, and doxycycline but a notable resistance to tylosin, trimethoprim, tobramycin, ciprofloxacin, and amikacin. Remarkably, 86.54% of the isolates exhibited a multidrug-resistant phenotype. Notably, we successfully screened a strain of B. bronchiseptica with a heteroresistance phenotype to gentamicin using population analysis profiling, which is a rare case. Biofilm-formation assays indicated that 96.15% of the isolates possessed biofilm-forming capabilities. These findings provide crucial insights into the prevalence of B. bronchiseptica in central China, facilitating the development of effective preventive measures to safeguard both animal and human health.}, }
@article {pmid38730049, year = {2024}, author = {Li, P and Zhang, Y and Chen, D and Lin, H}, title = {Investigation of a novel biofilm model close to the original oral microbiome.}, journal = {Applied microbiology and biotechnology}, volume = {108}, number = {1}, pages = {330}, pmid = {38730049}, issn = {1432-0614}, support = {82204253//National Natural Science Foundation of China/ ; 81970928//National Natural Science Foundation of China/ ; }, mesh = {Humans ; *Bacteria/genetics/classification/isolation &amp; purification ; *Biofilms/growth &amp; development ; *Culture Media/chemistry ; *Microbiota ; *Mouth/microbiology ; *RNA, Ribosomal, 16S/genetics ; *Saliva/microbiology ; Saliva, Artificial ; }, abstract = {A more optimized culture medium used in vitro to mimic the bacterial composition of original oral flora as similar as possible remains difficult at present, and the goal of this study is to develop a novel oral biofilm medium to restore the original oral microbiome. Firstly, we conducted a systematic literature review by searching PubMed and summarized the current reported culture media in vitro. Seven culture media were found. We used mixed saliva as the origin of oral species to compare the effects of the above media in culturing oral multispecies biofilms. Results indicated that among the seven media brain heart infusion containing 1% sucrose (BHIs) medium, PG medium, artificial saliva (AS) medium, and SHI medium could obviously gain large oral biofilm in vitro. The nutrients contained in different culture media may be suitable for the growth of different oral bacteria; therefore, we optimized several novel media accordingly. Notably, results of crystal violet staining showed that the biofilm cultured in our modified artificial saliva (MAS) medium had the highest amount of biofilm biomass. 16S rRNA gene sequencing showed that the operational taxonomic units (OTUs) and Shannon index of biofilm cultured in MAS medium were also the highest among all the tested media. More importantly, the 16S rRNA gene sequencing analysis indicated that the biofilm cultured in MAS medium was closer to the original saliva species. Besides, biofilm cultured by MAS was denser and produced more exopolysaccharides. MAS supported stable biofilm formation on different substrata. In conclusion, this study demonstrated a novel MAS medium that could culture oral biofilm in vitro closer to the original oral microbiome, showing a good application prospect. KEY POINTS: • We compare the effects of different media in culturing oral biofilms • A novel modified artificial saliva (MAS) medium was obtained in our study • The MAS medium could culture biofilm that was closer to oral microbiome.}, }
@article {pmid38729529, year = {2024}, author = {Islam, N and Reid, D}, title = {Inhaled antibiotics: A promising drug delivery strategies for efficient treatment of lower respiratory tract infections (LRTIs) associated with antibiotic resistant biofilm-dwelling and intracellular bacterial pathogens.}, journal = {Respiratory medicine}, volume = {227}, number = {}, pages = {107661}, doi = {10.1016/j.rmed.2024.107661}, pmid = {38729529}, issn = {1532-3064}, mesh = {Humans ; *Biofilms/drug effects ; Administration, Inhalation ; *Anti-Bacterial Agents/administration &amp; dosage ; *Respiratory Tract Infections/drug therapy/microbiology ; *Drug Delivery Systems ; Drug Resistance, Bacterial ; Streptococcus pneumoniae/drug effects ; Liposomes ; Bronchiectasis/drug therapy/microbiology ; Haemophilus influenzae/drug effects ; Pulmonary Disease, Chronic Obstructive/drug therapy ; Pseudomonas aeruginosa/drug effects ; Staphylococcus aureus/drug effects ; Cystic Fibrosis/microbiology/drug therapy/complications ; }, abstract = {Antibiotic-resistant bacteria associated with LRTIs are frequently associated with inefficient treatment outcomes. Antibiotic-resistant Streptococcus pneumoniae, Haemophilus influenzae, Pseudomonas aeruginosa, and Staphylococcus aureus, infections are strongly associated with pulmonary exacerbations and require frequent hospital admissions, usually following failed management in the community. These bacteria are difficult to treat as they demonstrate multiple adaptational mechanisms including biofilm formation to resist antibiotic threats. Currently, many patients with the genetic disease cystic fibrosis (CF), non-CF bronchiectasis (NCFB) and chronic obstructive pulmonary disease (COPD) experience exacerbations of their lung disease and require high doses of systemically administered antibiotics to achieve meaningful clinical effects, but even with high systemic doses penetration of antibiotic into the site of infection within the lung is suboptimal. Pulmonary drug delivery technology that reliably deliver antibacterials directly into the infected cells of the lungs and penetrate bacterial biofilms to provide therapeutic doses with a greatly reduced risk of systemic adverse effects. Inhaled liposomal-packaged antibiotic with biofilm-dissolving drugs offer the opportunity for targeted, and highly effective antibacterial therapeutics in the lungs. Although the challenges with development of some inhaled antibiotics and their clinicals trials have been studied; however, only few inhaled products are available on market. This review addresses the current treatment challenges of antibiotic-resistant bacteria in the lung with some clinical outcomes and provides future directions with innovative ideas on new inhaled formulations and delivery technology that promise enhanced killing of antibiotic-resistant biofilm-dwelling bacteria.}, }
@article {pmid38729238, year = {2024}, author = {Nosair, N and Elzayat, S and Elsharaby, R and Abdulghaffar, IA and Elfarargy, HH and Sharaf, NA}, title = {The association of bacterial biofilm and middle ear mucosa in patients with mucosal chronic suppurative otitis media.}, journal = {Acta otorrinolaringologica espanola}, volume = {75}, number = {4}, pages = {244-251}, doi = {10.1016/j.otoeng.2024.02.004}, pmid = {38729238}, issn = {2173-5735}, mesh = {Humans ; *Biofilms/growth &amp; development ; *Otitis Media, Suppurative/microbiology ; *Ear, Middle/microbiology ; Female ; Chronic Disease ; Male ; *Mucous Membrane/microbiology ; *Pseudomonas aeruginosa ; Adult ; Middle Aged ; Microscopy, Electron, Scanning ; Adolescent ; Child ; Young Adult ; Aged ; }, abstract = {OBJECTIVES: To evaluate the bacterial biofilm's role in mucosal chronic suppurative otitis media (CSOM) utilizing scanning electron microscopy (SEM).<br><br>METHODS: This study involved 123 participating patients with active and inactive mucosal CSOM who underwent tympanomastoid surgery. SEM was used to examine middle ear mucosa biopsies for the development of biofilms. Middle ear discharge or mucosal swabs from patients were cultured to detect any bacterial growth. The biofilm formation was correlated to the culture results.<br><br>RESULTS: The biofilm was present in 69.9 % of patients (59% of them were with active mucosal CSOM) and absent in 30.1% of the patients (70% of them were with inactive mucosal CSOM), being more statistically significant in active mucosal CSOM (p-value&#x202f;=&#x202f;0.003). A correlation that was statistically significant was found between active mucosal CSOM and higher grades (3 and 4) of biofilms (p-value <0.05). The mucosal CSOM type and the results of the culture had a relationship that was statistically significant (p-value <0.001). 60% of patients had positive culture (70% of them were with active mucosal CSOM). There was a statistically significant relation between Pseudomonas aeruginosa bacterial growth and active mucosal CSOM (p-value&#x202f;=&#x202f;0.004) as well as higher grades of biofilms in mucosal CSOM.<br><br>CONCLUSION: Mucosal CSOM, especially the active type, is a biofilm-related disease. There is a significant relation between the state of mucosal CSOM (active or inactive) and culture results with predominance of Pseudomonas aeruginosa bacterial growth in active mucosal CSOM and in higher grades of biofilms in mucosal CSOM.}, }
@article {pmid38729095, year = {2024}, author = {Liu, W and Wang, Y and Sun, Y and Xia, W and Qian, X and Bo, R and Huang, Y and Ruan, X}, title = {Baicalein inhibits biofilm formation of avian pathogenic Escherichia coli in vitro mainly by affecting adhesion.}, journal = {Research in veterinary science}, volume = {174}, number = {}, pages = {105291}, doi = {10.1016/j.rvsc.2024.105291}, pmid = {38729095}, issn = {1532-2661}, mesh = {*Flavanones/pharmacology ; *Biofilms/drug effects/growth &amp; development ; *Escherichia coli/drug effects/physiology ; *Bacterial Adhesion/drug effects ; Animals ; *Microbial Sensitivity Tests ; Anti-Bacterial Agents/pharmacology ; Poultry Diseases/microbiology/drug therapy ; Chickens ; Escherichia coli Infections/veterinary/microbiology/drug therapy ; Microscopy, Electron, Scanning ; }, abstract = {Avian pathogenic Escherichia coli (APEC) is a widespread bacterium that causes significant economic losses to the poultry industry. APEC biofilm formation may result in chronic, persistent, and recurrent infections in clinics, making treatment challenging. Baicalein is a natural product that exhibits antimicrobial and antibiofilm activities. This study investigates the inhibitory effect of baicalein on APEC biofilm formation at different stages. The minimum inhibitory concentration (MIC) of baicalein on APEC was determined, and the growth curve of APEC biofilm formation was determined. The effects of baicalein on APEC biofilm adhesion, accumulation, and maturation were observed using optical microscopy, confocal laser scanning microscopy, and scanning electron microscopy. The biofilm inhibition rate of baicalein was calculated at different stages. The MIC of baicalein against APEC was 256 μg/mL. The process of APEC biofilm maturation takes approximately 48 h after incubation, with initial adhesion completed at 12 h, and cell accumulation finished at 24 h. Baicalein had a significant inhibitory effect on APEC biofilm formation at concentrations above 1 μg/mL (p < 0.01). Notably, baicalein had the highest rate of biofilm formation inhibition when added at the adhesion stage. Therefore, it can be concluded that baicalein is a potent inhibitor of APEC biofilm formation in vitro and acts, primarily by inhibiting cell adhesion. These findings suggests that baicalein has a potential application for inhibiting APEC biofilm formation and provides a novel approach for the prevention and control APEC-related diseases.}, }
@article {pmid38729002, year = {2024}, author = {Jan, H and Ghayas, S and Higazy, D and Ahmad, NM and Yaghmur, A and Ciofu, O}, title = {Antibacterial and anti-biofilm activities of antibiotic-free phosphatidylglycerol/docosahexaenoic acid lamellar and non-lamellar liquid crystalline nanoparticles.}, journal = {Journal of colloid and interface science}, volume = {669}, number = {}, pages = {537-551}, doi = {10.1016/j.jcis.2024.04.186}, pmid = {38729002}, issn = {1095-7103}, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Phosphatidylglycerols/chemistry/pharmacology ; *Staphylococcus aureus/drug effects ; *Nanoparticles/chemistry ; *Docosahexaenoic Acids/chemistry/pharmacology ; *Staphylococcus epidermidis/drug effects ; *Microbial Sensitivity Tests ; Liquid Crystals/chemistry ; Particle Size ; }, abstract = {Infectious diseases, particularly those associated with biofilms, are challenging to treat due to an increased tolerance to commonly used antibiotics. This underscores the urgent need for innovative antimicrobial strategies. Here, we present an alternative simple-by-design approach focusing on the development of biocompatible and antibiotic-free nanocarriers from docosahexaenoic acid (DHA) that has the potential to combat microbial infections and phosphatidylglycerol (DOPG), which is attractive for use as a biocompatible prominent amphiphilic component of Gram-positive bacterial cell membranes. We assessed the anti-bacterial and anti-biofilm activities of these nanoformulations (hexosomes and vesicles) against S. aureus and S. epidermidis, which are the most common causes of infections on catheters and medical devices by different methods (including resazurin assay, time-kill assay, and confocal laser scanning microscopy on an in vitro catheter biofilm model). In a DHA-concentration-dependent manner, these nano-self-assemblies demonstrated strong anti-bacterial and anti-biofilm activities, particularly against S. aureus. A five-fold reduction of the planktonic and a four-fold reduction of biofilm populations of S. aureus were observed after treatment with hexosomes. The nanoparticles had a bacteriostatic effect against S. epidermidis planktonic cells but no anti-biofilm activity was detected. We discuss the findings in terms of nanoparticle-bacterial cell interactions, plausible alterations in the phospholipid membrane composition, and potential penetration of DHA into these membranes, leading to changes in their structural and biophysical properties. The implications for the future development of biocompatible nanocarriers for the delivery of DHA alone or in combination with other anti-bacterial agents are discussed, as novel treatment strategies of Gram-positive infections, including biofilm-associated infections.}, }
@article {pmid38728787, year = {2024}, author = {Xiong, F and Dai, T and Zheng, Y and Wen, D and Li, Q}, title = {Enhanced AHL-mediated quorum sensing accelerates the start-up of biofilm reactors by elevating the fitness of fast-growing bacteria in sludge and biofilm communities.}, journal = {Water research}, volume = {257}, number = {}, pages = {121697}, doi = {10.1016/j.watres.2024.121697}, pmid = {38728787}, issn = {1879-2448}, mesh = {*Biofilms ; *Quorum Sensing ; *Bioreactors ; *Sewage/microbiology ; Acyl-Butyrolactones/metabolism ; Bacteria/genetics/metabolism ; }, abstract = {Quorum sensing (QS)-based manipulations emerge as a promising solution for biofilm reactors to overcome challenges from inefficient biofilm formation and lengthy start-ups. However, the ecological mechanisms underlying how QS regulates microbial behaviors and community assembly remain elusive. Herein, by introducing different levels of N-acyl-homoserine lactones, we manipulated the strength of QS during the start-up of moving bed biofilm reactors and compared the dynamics of bacterial communities. We found that enhanced QS elevated the fitness of fast-growing bacteria with high ribosomal RNA operon (rrn) copy numbers in their genomes in both the sludge and biofilm communities. This led to notably increased extracellular substance production, as evidenced by strong positive correlations between community-level rrn copy numbers and extracellular proteins and polysaccharides (Pearson's r = 0.529-0.830, P < 0.001). Network analyses demonstrated that enhanced QS significantly promoted the ecological interactions among taxa, particularly cooperative interactions. Bacterial taxa with higher network degrees were more strongly correlated with extracellular substances, suggesting their crucial roles as public goods in regulating bacterial interactions and shaping network structures. However, the assembly of more cooperative communities in QS-enhanced reactors came at the cost of decreased network stability and modularity. Null model and dissimilarity-overlap curve analysis revealed that enhanced QS strengthened stochastic processes in community assembly and rendered the universal population dynamics more convergent. Additionally, these shaping effects were consistent for both the sludge and biofilm communities, underpinning the planktonic-to-biofilm transition. This work highlights that QS manipulations efficiently drive community assembly and confer specialized functional traits to communities by recruiting taxa with specific life strategies and regulating interspecific interactions. These ecological insights deepen our understanding of the rules governing microbial societies and provide guidance for managing engineering ecosystems.}, }
@article {pmid38727840, year = {2024}, author = {Patil, SB and Basrani, ST and Chougule, SA and Gavandi, TC and Karuppayil, SM and Jadhav, AK}, title = {Butyl isothiocyanate exhibits antifungal and anti-biofilm activity against Candida albicans by targeting cell membrane integrity, cell cycle progression and oxidative stress.}, journal = {Archives of microbiology}, volume = {206}, number = {6}, pages = {251}, pmid = {38727840}, issn = {1432-072X}, support = {DYPES/DU/R&amp;D/2021/273//D.Y. Patil Education Society Institution Deemed to be University Kolhapur/ ; DYPES/DU/R&amp;D/2021/273//D.Y. Patil Education Society Institution Deemed to be University Kolhapur/ ; DYPES/DU/R&amp;D/2021/273//D.Y. Patil Education Society Institution Deemed to be University Kolhapur/ ; }, mesh = {*Candida albicans/drug effects/physiology ; *Biofilms/drug effects ; *Antifungal Agents/pharmacology ; *Isothiocyanates/pharmacology ; *Oxidative Stress/drug effects ; *Cell Membrane/drug effects/metabolism ; *Reactive Oxygen Species/metabolism ; Microbial Sensitivity Tests ; Cell Cycle/drug effects ; Hyphae/drug effects/growth &amp; development ; Ergosterol/metabolism ; }, abstract = {The prevalence of Candida albicans infection has increased during the past few years, which contributes to the need for new, effective treatments due to the increasing concerns regarding antifungal drug toxicity and multidrug resistance. Butyl isothiocyanate (butylITC) is a glucosinolate derivative, and has shown a significant antifungal effect contrary to Candida albicans. Additionally, how butylITC affects the virulence traits of C. albicans and molecular mode of actions are not well known. Present study shows that at 17.36 mM concentration butylITC inhibit planktonic growth. butylITC initially slowed the hyphal transition at 0.542 mM concentration. butylITC hampered biofilm development, and inhibits biofilm formation at 17.36 mM concentration which was analysed using metabolic assay (XTT assay) and Scanning Electron Microscopy (SEM). In addition, it was noted that butylITC inhibits ergosterol biosynthesis. The permeability of cell membranes was enhanced by butylITC treatment. Moreover, butylITC arrests cells at S-phase and induces intracellular Reactive Oxygen Species (ROS) accumulation in C. albicans. The results suggest that butylITC may have a dual mode of action, inhibit virulence factors and modulate cellular processes like inhibit ergosterol biosynthesis, cell cycle arrest, induces ROS production which leads to cell death in C. albicans.}, }
@article {pmid38726949, year = {2024}, author = {Ding, M and Zhang, Y and Li, X and Li, Q and Xiu, W and He, A and Dai, Z and Dong, H and Shan, J and Mou, Y}, title = {Simultaneous Biofilm Disruption, Bacterial Killing, and Inflammation Elimination for Wound Treatment Using Silver Embellished Polydopamine Nanoplatform.}, journal = {Small (Weinheim an der Bergstrasse, Germany)}, volume = {20}, number = {36}, pages = {e2400927}, doi = {10.1002/smll.202400927}, pmid = {38726949}, issn = {1613-6829}, support = {82301104//National Natural Science Foundation of China/ ; BK20230160//Natural Science Foundation of Jiangsu Province/ ; YKK22182//Nanjing Medical Science and Technique Development Foundation/ ; 0222R208//"3456" Cultivation Program for Junior Talents of Nanjing Stomatological Hospital, Medical School of Nanjing University/ ; 0222R212//"3456" Cultivation Program for Junior Talents of Nanjing Stomatological Hospital, Medical School of Nanjing University/ ; 2019060009//Nanjing Clinical Research Center for Oral Diseases/ ; }, mesh = {*Indoles/chemistry/pharmacology ; *Biofilms/drug effects ; *Polymers/chemistry/pharmacology ; *Silver/chemistry/pharmacology ; Animals ; *Staphylococcus aureus/drug effects ; *Inflammation/drug therapy/pathology ; Mice ; Anti-Bacterial Agents/pharmacology/chemistry ; Wound Healing/drug effects ; Nanoparticles/chemistry ; }, abstract = {Due to the presence of spatial barriers, persistent bacteria, and excessive inflammation in bacteria biofilm-infected wounds, current nanoplatforms cannot effectively address these issues simultaneously during the therapeutic process. Herein, a novel biomimetic photothermal nanoplatform integrating silver and polydopamine nanoparticles (Ag/PDAs) that can damage biofilms, kill bacterial persisters, and reduce inflammation for wound treatment is presented. These findings reveal that Ag/PDAs exhibit a broad-spectrum antimicrobial activity through direct damage to the bacterial membrane structure. Additionally, Ag/PDAs demonstrate a potent photothermal conversion efficiency. When combined with near-infrared (NIR) irradiation, Ag/PDAs effectively disrupt the spatial structure of biofilms and synergistically eradicate the resident bacteria. Furthermore, Ag/PDAs show remarkable anti-inflammatory properties in counteracting bacterium-induced macrophage polarization. The in vivo results confirm that the topical application of Ag/PDAs significantly suppress Staphylococcus aureus biofilm-infected wounds in murine models, concurrently facilitating wound healing. This research provides a promising avenue for the eradication of bacterial biofilms and the treatment of biofilm-infected wounds.}, }
@article {pmid38725978, year = {2024}, author = {Okouakoua, FY and Kayath, CA and Mokemiabeka, SN and Moukala, DCR and Kaya-Ongoto, MD and Nguimbi, E}, title = {Involvement of the Bacillus SecYEG Pathway in Biosurfactant Production and Biofilm Formation.}, journal = {International journal of microbiology}, volume = {2024}, number = {}, pages = {6627190}, pmid = {38725978}, issn = {1687-918X}, abstract = {With Bacillus species, about 30% of extracellular proteins are translocated through the cytoplasmic membrane, coordinated by the Sec translocase. This system mainly consists of the cytoplasmic ATPase SecA and the membrane-embedded SecYEG channel. The purpose of this work was to investigate the effects of the SecYEG export system on the production of industrial biomolecules, such as biosurfactants, proteases, amylases, and cellulases. Fifty-two isolates of Bacillus species were obtained from traditional fermented foods and then characterized using molecular microbiology methods. The isolates secreted exoenzymes that included cellulases, amylases, and proteases. We present evidence that a biosurfactant-like molecule requires the SecA ATPase and the SecYEG membrane channel for its secretion. In addition, we showed that biomolecules involved in biofilm formation required the SecYEG pathway. This work presents a novel seven-target fragment multiplex PCR assay capable of identification at the species level of Bacillus through a unique SecDF chromosomal gene. The bacterial membrane protein SecDF allowed the discrimination of Bacillus subtilis, B. licheniformis, B. amyloliquefaciens, and B. sonorensis. SecA was able to interact with AprE, AmyE, and TasA. The Rose Bengal inhibitor of SecA crucially affected the interaction of AprE, AmyE, TapA, and TasA with recombinant Gst-SecA. The Rose Bengal prevented Bacillus species from secreting and producing proteases, cellulases, amylases, and biosurfactant-like molecules. It also inhibited the formation of biofilm cell communities. The data support, for the first time, that the SecYEG translocon mediates the secretion of a biosurfactant-like molecule.}, }
@article {pmid38724834, year = {2024}, author = {Nayak, R and Rai, VK and Pradhan, D and Halder, J and Rajwar, TK and Dash, P and Das, C and Mishra, A and Mahanty, R and Saha, I and Manoharadas, S and Kar, B and Ghosh, G and Rath, G}, title = {Exploring the Biofilm Inhibition Potential of a Novel Phytic Acid-Crosslinked Chitosan Nanoparticle: In Vitro and In Vivo Investigations.}, journal = {AAPS PharmSciTech}, volume = {25}, number = {5}, pages = {106}, pmid = {38724834}, issn = {1530-9932}, mesh = {*Biofilms/drug effects ; *Phytic Acid/chemistry/pharmacology/therapeutic use ; *Cross-Linking Reagents/chemistry/pharmacology/therapeutic use ; *Chitosan/chemistry/pharmacology/therapeutic use ; *Nanoparticles/chemistry/therapeutic use ; *Antifungal Agents/chemistry/pharmacology/therapeutic use ; *Anti-Inflammatory Agents, Non-Steroidal/chemistry/pharmacology/therapeutic use ; Microbial Sensitivity Tests ; Cytokines/immunology ; *Candida albicans/drug effects/pathogenicity ; Female ; Animals ; Mice ; *Candidiasis, Vulvovaginal/drug therapy/metabolism ; Vagina/microbiology ; }, abstract = {The primary factor underlying the virulence of Candida albicans is its capacity to form biofilms, which in turn leads to recurrent complications. Over-the-counter antifungal treatments have proven ineffective in eliminating fungal biofilms and the inflammatory cytokines produced during fungal infections. Chitosan nanoparticles offer broad and versatile therapeutic potential as both antifungal agents and carriers for antifungal drugs to combat biofilm-associated Candida infections. In our study, we endeavoured to develop chitosan nanoparticles utilising chitosan and the antifungal crosslinker phytic acid targeting C. albicans. Phytic acid, known for its potent antifungal and anti-inflammatory properties, efficiently crosslinks with chitosan. The nanoparticles were synthesised using the ionic gelation technique and subjected to analyses including Fourier transform infrared spectroscopy, dynamic light scattering, and zeta potential analysis. The synthesised nanoparticles exhibited dimensions with a diameter (Dh) of 103 ± 3.9 nm, polydispersity index (PDI) of 0.33, and zeta potential (ZP) of 37 ± 2.5 mV. These nanoparticles demonstrated an antifungal effect with a minimum inhibitory concentration (MIC) of 140 ± 2.2 µg/mL, maintaining cell viability at approximately 90% of the MIC value and reducing cytokine levels. Additionally, the nanoparticles reduced ergosterol content and exhibited a 62% ± 1.2 reduction in biofilm susceptibility, as supported by colony-forming unit (CFU) and XTT assays-furthermore, treatment with nanoparticles reduced exopolysaccharide production and decreased secretion of aspartyl protease by C. albicans. Our findings suggest that the synthesised nanoparticles effectively combat Candida albicans infections. In vivo studies conducted on a mouse model of vaginal candidiasis confirmed the efficacy of the nanoparticles in combating fungal infections in vivo.}, }
@article {pmid38723991, year = {2024}, author = {Xie, Z and Ou, Z and Zhang, M and Tang, G and Cheng, X and Cao, W and Luo, J and Fang, F and Sun, Y and Li, M and Cai, J and Feng, Q}, title = {Indole-3-acetic acid regulating the initial adhesion of microalgae in biofilm formation.}, journal = {Environmental research}, volume = {252}, number = {Pt 4}, pages = {119093}, doi = {10.1016/j.envres.2024.119093}, pmid = {38723991}, issn = {1096-0953}, mesh = {*Indoleacetic Acids/metabolism/pharmacology ; *Biofilms/drug effects/growth &amp; development ; *Microalgae/drug effects/physiology ; Plant Growth Regulators/pharmacology ; }, abstract = {Regulating the microalgal initial adhesion in biofilm formation is a key approach to address the challenges of attached microalgae cultivation. As a type of phytohormone, Indole-3-acetic acid (IAA) can promote the growth and metabolism of microalgae. However, limited knowledge has been acquired of how IAA can change the initial adhesion of microalgae in biofilm formation. This study focused on investigating the initial adhesion of microalgae under different IAA concentrations exposure in biofilm formation. The results showed that IAA showed obvious hormesis-like effects on the initial adhesion ability of microalgae biofilm. Under exposure to the low concentration (0.1 mg/L) of IAA, the initial adhesion quantity of microalgae on the surface of the carrier reached the highest value of 7.2 g/m[2]. However, exposure to the excessively high concentration (10 mg/L) of IAA led to a decrease in the initial adhesion capability of microalgal biofilms. The enhanced adhesion of microalgal biofilms due to IAA was attributed to the upregulation of genes related to the Calvin Cycle, which promoted the synthesis of hydrophobic amino acids, leading to increased protein secretion and altering the surface electron donor characteristics of microalgal biofilms. This, in turn, reduced the energy barrier between the carriers and microalgae. The research findings would provide crucial support for the application of IAA in regulating the operation of microalgal biofilm systems.}, }
@article {pmid38723954, year = {2024}, author = {Wu, T and Ding, J and Wang, S and Pang, JW and Sun, HJ and Zhong, L and Ren, NQ and Yang, SS}, title = {Insight into effect of polyethylene microplastic on nitrogen removal in moving bed biofilm reactor: Focusing on microbial community and species interactions.}, journal = {The Science of the total environment}, volume = {932}, number = {}, pages = {173033}, doi = {10.1016/j.scitotenv.2024.173033}, pmid = {38723954}, issn = {1879-1026}, mesh = {*Biofilms ; *Nitrogen/metabolism ; *Bioreactors/microbiology ; *Water Pollutants, Chemical/analysis ; *Polyethylene ; *Waste Disposal, Fluid/methods ; *Microbiota/drug effects ; Microplastics ; Wastewater/chemistry ; }, abstract = {Microplastics (MPs) pollution has emerged as a global concern, and wastewater treatment plants (WWTPs) are one of the potential sources of MPs in the environment. However, the effect of polyethylene MPs (PE) on nitrogen (N) removal in moving bed biofilm reactor (MBBR) remains unclear. We hypothesized that PE would affect N removal in MBBR by influencing its microbial community. In this study, we investigated the impacts of different PE concentrations (100, 500, and 1000 μg/L) on N removal, enzyme activities, and microbial community in MBBR. Folin-phenol and anthrone colorimetric methods, oxidative stress and enzyme activity tests, and high-throughput sequencing combined with bioinformation analysis were used to decipher the potential mechanisms. The results demonstrated that 1000 μg/L PE had the greatest effect on NH4[+]-N and TN removal, with a decrease of 33.5 % and 35.2 %, and nitrifying and denitrifying enzyme activities were restrained by 29.5-39.6 % and 24.6-47.4 %. Polysaccharide and protein contents were enhanced by PE, except for 1000 μg/L PE, which decreased protein content by 65.4 mg/g VSS. The positive links of species interactions under 1000 μg/L PE exposure was 52.07 %, higher than under 500 μg/L (51.05 %) and 100 μg/L PE (50.35 %). Relative abundance of some metabolism pathways like carbohydrate metabolism and energy metabolism were restrained by 0.07-0.11 % and 0.27-0.4 %. Moreover, the total abundance of nitrification and denitrification genes both decreased under PE exposure. Overall, PE reduced N removal by affecting microbial community structure and species interactions, inhibiting some key metabolic pathways, and suppressing key enzyme activity and functional gene abundance. This paper provides new insights into assessing the risk of MPs to WWTPs, contributing to ensuring the health of aquatic ecosystems.}, }
@article {pmid38723731, year = {2024}, author = {Wang, J and Guo, Y and Lu, W and Liu, X and Zhang, J and Sun, J and Chai, G}, title = {Dry powder inhalation containing muco-inert ciprofloxacin and colistin co-loaded liposomes for pulmonary P. Aeruginosa biofilm eradication.}, journal = {International journal of pharmaceutics}, volume = {658}, number = {}, pages = {124208}, doi = {10.1016/j.ijpharm.2024.124208}, pmid = {38723731}, issn = {1873-3476}, mesh = {*Ciprofloxacin/administration &amp; dosage/pharmacology/chemistry ; *Liposomes ; *Pseudomonas aeruginosa/drug effects/physiology ; *Biofilms/drug effects ; *Colistin/administration &amp; dosage/pharmacology ; Administration, Inhalation ; Animals ; *Anti-Bacterial Agents/administration &amp; dosage/pharmacology/chemistry ; *Pseudomonas Infections/drug therapy ; *Dry Powder Inhalers ; Mice ; Aerosols ; Lung/microbiology/drug effects ; Powders ; Female ; Particle Size ; }, abstract = {Pseudomonas aeruginosa (PA), a predominant pathogen in lung infections, poses significant challenges due to its biofilm formation, which is the primary cause of chronic and recalcitrant pulmonary infections. Bacteria within these biofilms exhibit heightened resistance to antibiotics compared to their planktonic counterparts, and their secreted toxins exacerbate lung infections. Diverging from traditional antibacterial therapy for biofilm eradication, this study introduces a novel dry powder inhalation containing muco-inert ciprofloxacin and colistin co-encapsulated liposomes (Cipro-Col-Lips) prepared using ultrasonic spray freeze drying (USFD) technique. This USFD dry powder is designed to efficiently deliver muco-inert Cipro-Col-Lips to the lungs. Once deposited, the liposomes rapidly diffuse into the airway mucus, reaching the biofilm sites. The muco-inert Cipro-Col-Lips neutralize the biofilm-secreted toxins and simultaneously trigger the release of their therapeutic payload, exerting a synergistic antibiofilm effect. Our results demonstrated that the optimal USFD liposomal dry powder formulation exhibited satisfactory in vitro aerosol performance in terms of fine particle fraction (FPF) of 44.44 ± 0.78 %, mass median aerodynamic diameter (MMAD) of 4.27 ± 0.21 μm, and emitted dose (ED) of 99.31 ± 3.31 %. The muco-inert Cipro-Col-Lips effectively penetrate the airway mucus and accumulate at the biofilm site, neutralizing toxins and safeguarding lung cells. The triggered release of ciprofloxacin and colistin works synergistically to reduce the biofilm's antibiotic resistance, impede the development of antibiotic resistance, and eliminate 99.99 % of biofilm-embedded bacteria, including persister bacteria. Using a PA-beads induced biofilm-associated lung infection mouse model, the in vivo efficacy of this liposomal dry powder aerosol was tested, and the results demonstrated that this liposomal dry powder aerosol achieved a 99.7 % reduction in bacterial colonization, and significantly mitigated inflammation and pulmonary fibrosis. The USFD dry powder inhalation containing muco-inert Cipro-Col-Lips emerges as a promising therapeutic strategy for treating PA biofilm-associated lung infections.}, }
@article {pmid38723699, year = {2024}, author = {Jo, S and Chao, C and Khilnani, TK and Shenoy, A and Bostrom, MPG and Carli, AV}, title = {The Infected Polypropylene Mesh: When Does Biofilm Form and Which Antiseptic Solution Most Effectively Removes It?.}, journal = {The Journal of arthroplasty}, volume = {39}, number = {8S1}, pages = {S294-S299}, doi = {10.1016/j.arth.2024.04.081}, pmid = {38723699}, issn = {1532-8406}, mesh = {*Biofilms/drug effects ; *Polypropylenes ; *Surgical Mesh/microbiology ; *Anti-Infective Agents, Local ; *Escherichia coli/drug effects ; Humans ; *Staphylococcus aureus/drug effects ; Prosthesis-Related Infections/microbiology/prevention &amp; control ; Povidone-Iodine/pharmacology ; Chlorhexidine/analogs &amp; derivatives/pharmacology ; Microscopy, Electron, Scanning ; }, abstract = {BACKGROUND: Polypropylene (PPE) mesh is commonly utilized to reconstruct catastrophic extensor mechanism disruptions in revision total knee arthroplasty. Unfortunately, these procedures are associated with a high rate of periprosthetic joint infection. The purpose of the current study was to: 1) visualize and quantify the progression of bacterial biofilm growth on PPE-mesh; and 2) determine which antiseptic solutions effectively remove viable bacteria.<br><br>METHODS: Knitted PPE mesh samples were cultured with either methicillin-sensitive Staphylococcus aureus (MSSA) or Escherichia coli (E.&#xa0;coli) for 7 days, with regular quantification of colony forming units (CFUs) and visualization using scanning electron microscopy to identify maturity. Immature (24&#xa0;hour) and mature (72&#xa0;hour) biofilm was treated with one of 5 commercial antiseptics for 3 minutes. A 0.05% chlorhexidine gluconate, a surfactant-based formulation of ethanol, acetic acid, sodium acetate, benzalkonium chloride, diluted povidone-iodine (0.35%), undiluted (10%) povidone-iodine, and 1:1 combination of 10% povidone-iodine and 3% hydrogen peroxide. A 3-log reduction in CFUs compared to saline was considered clinically meaningful.<br><br>RESULTS: The CFU counts plateaued, indicating maturity, at 72&#xa0;hours for both MSSA and E.&#xa0;coli. The scanning electron microscopy confirmed confluent biofilm formation after 72&#xa0;hours. The 10% povidone-iodine was clinically effective against all MSSA biofilms and immature E.&#xa0;coli biofilms. The 10% povidone-iodine with hydrogen peroxide was effective in all conditions. Only 10% povidone iodine formulations produced significantly (P < .0083) reduced CFU counts against mature biofilms.<br><br>CONCLUSIONS: Bacteria rapidly form biofilm on PPE mesh. Mesh contamination can be catastrophic, and clinicians should consider utilizing an antiseptic solution at the conclusion of mesh implantation. Undiluted povidone-iodine with hydrogen peroxide should be considered when attempting to salvage infected PPE mesh.}, }
@article {pmid38723695, year = {2024}, author = {Kim, BH and Ashrafudoulla, M and Shaila, S and Park, HJ and Sul, JD and Park, SH and Ha, SD}, title = {Isolation, characterization, and application of bacteriophage on Vibrio parahaemolyticus biofilm to control seafood contamination.}, journal = {International journal of antimicrobial agents}, volume = {64}, number = {1}, pages = {107194}, doi = {10.1016/j.ijantimicag.2024.107194}, pmid = {38723695}, issn = {1872-7913}, mesh = {*Vibrio parahaemolyticus/virology ; *Biofilms ; *Bacteriophages/isolation &amp; purification/physiology/genetics ; *Seafood/microbiology ; Animals ; Decapodiformes/microbiology ; Perciformes/microbiology ; Food Contamination/prevention &amp; control ; Host Specificity ; Biological Control Agents ; }, abstract = {OBJECTIVE: This study intended to isolate a Vibrio-particular phage from the natural environment, analyse its characteristics and genome sequence, and investigate its reduction effect on V. parahaemolyticus biofilm as a biocontrol agent in squid and mackerel.<br><br>METHODS: Among 21 phages, phage CAU_VPP01, isolated from beach mud, was chosen for further experiments based on host range and EOP tests. When examining the reduction effect of phage CAU_VPP01 against Vibrio parahaemolyticus biofilms on surfaces (stainless steel [SS] and polyethylene terephthalate [PET]) and food surfaces (squid and mackerel).<br><br>RESULTS: The phage showed the most excellent reduction effect at a multiplicity-of-infection (MOI) 10. Three-dimensional images acquired with confocal laser scanning microscopy (CLSM) analysis were quantified using COMSTAT, which showed that biomass, average thickness, and roughness coefficient decreased when treated with the phage. Colour and texture analysis confirmed that the quality of squid and mackerel was maintained after the phage treatment. Finally, a comparison of gene expression levels determined by qRT-PCR analysis showed that the phage treatment induced a decrease in the gene expression of flaA, vp0962, andluxS, as examples.<br><br>CONCLUSION: This study indicated that Vibrio-specific phage CAU_VPP01 effectively controlled V. parahaemolyticus biofilms under various conditions and confirmed that the isolated phage could possibly be used as an effective biocontrol weapon in the seafood manufacturing industry.}, }
@article {pmid38723502, year = {2024}, author = {Yan, Z and Han, X and Wang, H and Jin, Y and Song, X}, title = {Influence of aeration modes and DO on simultaneous nitrification and denitrification in treatment of hypersaline high-strength nitrogen wastewater using sequencing batch biofilm reactor (SBBR).}, journal = {Journal of environmental management}, volume = {359}, number = {}, pages = {121075}, doi = {10.1016/j.jenvman.2024.121075}, pmid = {38723502}, issn = {1095-8630}, mesh = {*Nitrification ; *Biofilms ; *Bioreactors ; *Nitrogen/metabolism ; *Wastewater ; *Denitrification ; Waste Disposal, Fluid/methods ; Salinity ; Oxygen/metabolism ; }, abstract = {Sequencing batch biofilm reactor (SBBR) has the potential to treat hypersaline high-strength nitrogen wastewater by simultaneous nitrification-denitrification (SND). Dissolved oxygen (DO) and aeration modes are major factors affecting pollutant removal. Low DO (0.35-3.5 mg/L) and alternative anoxic/aerobic (A/O) mode are commonly used for municipal wastewater treatment, however, the appropriate DO concentration and operation mode are still unknown under hypersaline environment because of the restricted oxygen transfer in denser extracellular polymeric substances (EPS) barrier and the decreased carbon source consumption during the anoxic phase. Herein, two SBBRs (R1, fully aerobic mode; R2, A/O mode) were used for the treatment of hypersaline high-strength nitrogen wastewater (200 mg/L NH4[+]-N, COD/N of 3 and 3% salinity). The results showed that the relatively low DO (2 mg/L) could not realize effective nitrification, while high DO (4.5 mg/L) evidently increased nitrification efficiency by enhancing oxygen transfer in denser biofilm that was stimulated by high salinity. A stable SND was reached 16 days faster with a ∼10% increase of TN removal under A/O mode. Mechanism analysis found that denser biofilm with coccus and bacillus were present in A/O mode instead of filamentous microorganisms, with the secretion of more EPS. Corynebacterium and Halomonas were the dominant genera in both SBBRs, and HN-AD process might assist partial nitrification-denitrification (PND) for highly efficient TN removal in biofilm systems. By using the appropriate operation mode and parameters, the average NH4[+]-N and TN removal efficiency could respectively reach 100% and 70.8% under the NLR of 0.2 kg N·m[-3]·d[-1] (COD/N of 3), which was the highest among the published works using SND-based SBBRs in treatment of saline high-strength ammonia nitrogen (low COD/N) wastewater. This study provided new insights in biofilm under hypersaline stress and provided a solution for the treatment of hypersaline high-strength nitrogen (low COD/N) water.}, }
@article {pmid38723421, year = {2024}, author = {Reis-Neta, GRD and Ricomini-Filho, AP and Martorano-Fernandes, L and Vargas-Moreno, VF and Cury, AADB and Marcello-Machado, RM}, title = {Effect of hydroxyapatite nanoparticles coating of titanium surface on biofilm adhesion: An in vitro study.}, journal = {Archives of oral biology}, volume = {164}, number = {}, pages = {105986}, doi = {10.1016/j.archoralbio.2024.105986}, pmid = {38723421}, issn = {1879-1506}, mesh = {*Titanium/chemistry/pharmacology ; *Candida albicans/drug effects/physiology ; *Biofilms/drug effects ; *Durapatite/pharmacology/chemistry ; *Streptococcus sanguis/drug effects ; *Nanoparticles/chemistry ; *Surface Properties ; *Microscopy, Electron, Scanning ; *Dental Implants/microbiology ; *Microscopy, Confocal ; In Vitro Techniques ; Bacterial Adhesion/drug effects ; Wettability ; Coated Materials, Biocompatible/pharmacology/chemistry ; Acid Etching, Dental ; Microbial Viability/drug effects ; }, abstract = {AIM: To evaluate the adhesion of mono and duospecies biofilm on a commercially available dental implant surface coated with hydroxyapatite nanoparticles (nanoHA).<br><br>MATERIAL AND METHODS: Titanium discs were divided into two groups: double acid-etched (AE) and AE coated with nanoHA (NanoHA). Surface characteristics evaluated were morphology, topography, and wettability. Mono and duospecies biofilms of Streptococcus sanguinis (S. sanguinis) and Candida albicans (C. albicans) were formed. Discs were exposed to fetal bovine serum (FBS) to form the pellicle. Biofilm was growth in RPMI1640 medium with 10% FBS and 10% BHI medium for 6&#xa0;h. Microbial viability was evaluated using colony-forming unit and metabolic activity by a colorimetric assay of the tetrazolium salt XTT. Biofilm architecture and organization were evaluated by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM).<br><br>RESULTS: AE surface had more pores, while NanoHA had even nanoHA crystals distribution. Roughness was similar (AE: 0.59&#xa0;&#xb1;&#xa0;0.07&#xa0;&#xb5;m, NanoHA: 0.69&#xa0;&#xb1;&#xa0;0.18&#xa0;&#xb5;m), but wettability was different (AE: &#x398;w= 81.79&#xa0;&#xb1;&#xa0;8.55&#xb0;, NanoHA: &#x398;w= 53.26&#xa0;&#xb1;&#xa0;11.86&#xb0;; P&#xa0;=&#xa0;0.01). NanoHA had lower S. sanguinis viability in monospecies biofilm (P&#xa0;=&#xa0;0.007). Metabolic activity was similar among all biofilms. In SEM both surfaces on C. albicans biofilm show a similar distribution of hyphae in mono and duospecies biofilms. AE surface has more S. sanguinis than the NanoHA surface in the duospecies biofilm. CLSM showed a large proportion of live cells in all groups.<br><br>CONCLUSIONS: The nanoHA surface reduced the adhesion of S. sanguinis biofilm but did not alter the adhesion of C. albicans or the biofilm formed by both species.}, }
@article {pmid38723349, year = {2024}, author = {Zhang, H and Cheng, Y and Qiu, L and Zeng, W and Hu, T and Yang, J and Wang, J and Wang, H and Gong, W and Liang, H}, title = {In situ electron generation through Fe/C supported sludge coupled with a counter-diffusion biofilm for electron-deficient wastewater treatment: Binding properties and catalytic competition mechanism of nitrate reductase.}, journal = {Water research}, volume = {257}, number = {}, pages = {121688}, doi = {10.1016/j.watres.2024.121688}, pmid = {38723349}, issn = {1879-2448}, mesh = {*Biofilms ; *Sewage/microbiology ; *Electrons ; *Waste Disposal, Fluid/methods ; *Iron/metabolism ; *Wastewater/chemistry ; Nitrate Reductase/metabolism ; Oxidation-Reduction ; Bioreactors ; Carbon ; }, abstract = {A membrane-aerated biofilm-coupled Fe/C supported sludge system (MABR-Fe/C) was constructed to achieve in situ electron production for NO3[-]-N reduction enhancement in different Fe/C loadings (10 g and 200 g). The anoxic environment formed in the MABR-Fe/C promoted a continual Fe[2+]release of Fe/C in 120 d operation (average Fe[2+]concentrations is 1.18 and 2.95 mg/L in MABR-Fe/C10 and MABR-Fe/C200, respectively). Metagenomics results suggested that the electrons generated from ongoing Fe[2+] oxidation were transferred via the Quinone pool to EC 1.7.5.1 rather than EC 1.9.6.1 to complete the process of NO3[-]-N reduction to NO2[-]-N in Acidovorax, Ottowia, and Polaromonas. In the absence of organic matter, the NO3[-]-N removal in MABR-Fe/C10 and MABR-Fe/C200 increased by 11.99 and 12.52 mg/L, respectively, compared to that in MABR. In the further NO2[-]-N reduction, even if the minimum binding free energy (MBFE) was low, NO2[-]-N in Acidovorax and Dechloromonas preferentially bind the Gln-residues for dissimilatory nitrate reduction (DNR) in the presence of Fe/C. Increasing Fe/C loading (MABR-Fe/C200) caused the formation of different residue binding sites, further enhancing the already dominant DNR. When DNR in MABR-Fe/C200 intensified, the TN in the effluent increased by 3.75 mg/L although the effluent NO3[-]-N concentration was lower than that in MABR-Fe/C10. This study demonstrated a new MABR-Fe/C system for in situ electron generation to enhance biological nitrogen removal and analyzed the NO3[-]-N reduction pathway and metabolic mechanism, thus providing new ideas for nitrogen removal in electron-deficient wastewater.}, }
@article {pmid38722774, year = {2024}, author = {Noori, R and Bano, N and Ahmad, S and Mirza, K and Mazumder, JA and Perwez, M and Raza, K and Manzoor, N and Sardar, M}, title = {Microbial Biofilm Inhibition Using Magnetic Cross-Linked Polyphenol Oxidase Aggregates.}, journal = {ACS applied bio materials}, volume = {7}, number = {5}, pages = {3164-3178}, doi = {10.1021/acsabm.4c00175}, pmid = {38722774}, issn = {2576-6422}, mesh = {*Biofilms/drug effects ; *Catechol Oxidase/metabolism/chemistry/antagonists &amp; inhibitors ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Particle Size ; Materials Testing ; Biocompatible Materials/chemistry/pharmacology ; Microbial Sensitivity Tests ; Cross-Linking Reagents/chemistry/pharmacology ; Molecular Docking Simulation ; Escherichia coli/drug effects ; }, abstract = {Microbial biofilm accumulation poses a serious threat to the environment, presents significant challenges to different industries, and exhibits a large impact on public health. Since there has not been a conclusive answer found despite various efforts, the potential green and economical methods are being focused on, particularly the innovative approaches that employ biochemical agents. In the present study, we propose a bio-nanotechnological method using magnetic cross-linked polyphenol oxidase aggregates (PPO m-CLEA) for inhibition of microbial biofilm including multidrug resistant bacteria. Free PPO solution showed only 55-60% biofilm inhibition, whereas m-CLEA showed 70-75% inhibition, as confirmed through microscopic techniques. The carbohydrate and protein contents in biofilm extracellular polymeric substances (EPSs) were reduced significantly. The m-CLEA demonstrated reusability up to 5 cycles with consistent efficiency in biofilm inhibition. Computational work was also done where molecular docking of PPO with microbial proteins associated with biofilm formation was conducted, resulting in favorable binding scores and inter-residual interactions. Overall, both in vitro and in silico results suggest that PPO interferes with microbial cell attachment and EPS formation, thereby preventing biofilm colonization.}, }
@article {pmid38722243, year = {2024}, author = {Perasoli, FB and B Silva, LS and C Figueiredo, BI and Pinto, IC and F Amaro, LJ and S Almeida Bastos, JC and Carneiro, SP and R Araújo, VP and G Beato, FR and M Barboza, AP and M Teixeira, LF and Gallagher, MP and Bradley, M and Venkateswaran, S and H Dos Santos, OD}, title = {Poly(methylmethacrylate-co-dimethyl acrylamide)-silver nanocomposite prevents biofilm formation in medical devices.}, journal = {Nanomedicine (London, England)}, volume = {19}, number = {14}, pages = {1285-1296}, pmid = {38722243}, issn = {1748-6963}, support = {//Conselho Nacional de Desenvolvimento Cient&#xed;fico e Tecnol&#xf3;gico/ ; 01//Coordena&#xe7;&#xe3;o de Aperfei&#xe7;oamento de Pessoal de N&#xed;vel Superior/ ; APQ02429-22, APQ01953-22//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado de Minas Gerais/ ; }, mesh = {*Biofilms/drug effects ; *Silver/chemistry/pharmacology ; *Nanocomposites/chemistry ; *Metal Nanoparticles/chemistry ; Humans ; Anti-Bacterial Agents/pharmacology/chemistry ; Bacterial Adhesion/drug effects ; Equipment and Supplies/microbiology ; Hemolysis/drug effects ; Acrylamides/chemistry/pharmacology ; }, abstract = {Aim: To investigate whether medical devices coated with a synthesized nanocomposite of poly(methylmethacrylate-co-dimethyl acrylamide) (PMMDMA) and silver nanoparticles (AgNPs) could improve their antibiofilm and antimicrobial activities. We also investigated the nanocomposite's safety. Materials &amp; methods: The nanocomposite was synthesized and characterized using analytical techniques. Medical devices coated with the nanocomposite were evaluated for bacterial adhesion and hemolytic activity in vitro. Results: The nanocomposite formation was demonstrated with the incorporation of AgNPs into the polymer matrix. The nanocomposite proved to be nonhemolytic and significantly inhibited bacterial biofilm formation. Conclusion: The PMMDMA-AgNPs nanocomposite was more effective in preventing biofilm formation than PMMDMA alone and is a promising strategy for coating medical devices and reducing mortality due to hospital-acquired infections.}, }
@article {pmid38722159, year = {2024}, author = {Jarrett, CO and Leung, JM and Motoshi, S and Sturdevant, DE and Zhang, Y and Hoyt, FH and Hinnebusch, BJ}, title = {Role of the Yersinia pestis phospholipase D (Ymt) in the initial aggregation step of biofilm formation in the flea.}, journal = {mBio}, volume = {15}, number = {6}, pages = {e0012424}, pmid = {38722159}, issn = {2150-7511}, support = {//HHS | NIH | NIAID | Division of Intramural Research (DIR, NIAID)/ ; }, mesh = {*Yersinia pestis/enzymology ; *Phospholipase D/metabolism ; *Siphonaptera/microbiology ; *Biofilms/growth &amp; development ; Plague/microbiology/transmission ; Extracellular Polymeric Substance Matrix/chemistry/microbiology/ultrastructure ; Polysaccharides/metabolism ; Microscopy, Electron, Transmission ; Proteome/metabolism ; Animals ; Mice ; Lipids/analysis ; }, abstract = {UNLABELLED: Transmission of Yersinia pestis by fleas depends on the formation of condensed bacterial aggregates embedded within a gel-like matrix that localizes to the proventricular valve in the flea foregut and interferes with normal blood feeding. This is essentially a bacterial biofilm phenomenon, which at its end stage requires the production of a Y. pestis exopolysaccharide that bridges the bacteria together in a cohesive, dense biofilm that completely blocks the proventriculus. However, bacterial aggregates are evident within an hour after a flea ingests Y. pestis, and the bacterial exopolysaccharide is not required for this process. In this study, we characterized the biochemical composition of the initial aggregates and demonstrated that the yersinia murine toxin (Ymt), a Y. pestis phospholipase D, greatly enhances rapid aggregation following infected mouse blood meals. The matrix of the bacterial aggregates is complex, containing large amounts of protein and lipid (particularly cholesterol) derived from the flea's blood meal. A similar incidence of proventricular aggregation occurred after fleas ingested whole blood or serum containing Y. pestis, and intact, viable bacteria were not required. The initial aggregation of Y. pestis in the flea gut is likely due to a spontaneous physical process termed depletion aggregation that occurs commonly in environments with high concentrations of polymers or other macromolecules and particles such as bacteria. The initial aggregation sets up subsequent binding aggregation mediated by the bacterially produced exopolysaccharide and mature biofilm that results in proventricular blockage and efficient flea-borne transmission.<br><br>IMPORTANCE: Yersinia pestis, the bacterial agent of plague, is maintained in nature in mammal-flea-mammal transmission cycles. After a flea feeds on a mammal with septicemic plague, the bacteria rapidly coalesce in the flea's digestive tract to form dense aggregates enveloped in a viscous matrix that often localizes to the foregut. This represents the initial stage of biofilm development that potentiates transmission of Y. pestis when the flea later bites a new host. The rapid aggregation likely occurs via a depletion-aggregation mechanism, a non-canonical first step of bacterial biofilm development. We found that the biofilm matrix is largely composed of host blood proteins and lipids, particularly cholesterol, and that the enzymatic activity of a Y. pestis phospholipase D (Ymt) enhances the initial aggregation. Y. pestis transmitted by flea bite is likely associated with this host-derived matrix, which may initially shield the bacteria from recognition by the host's intradermal innate immune response.}, }
@article {pmid38721917, year = {2024}, author = {Wang, J and Mao, D and Dai, B and Rui, Y}, title = {Silicon-induced biofilm improves peripheral nerve defect in rats mediated by VEGF/VEGFR2/ERK.}, journal = {Neurological research}, volume = {46}, number = {8}, pages = {743-751}, doi = {10.1080/01616412.2024.2352232}, pmid = {38721917}, issn = {1743-1328}, mesh = {Animals ; *Vascular Endothelial Growth Factor Receptor-2/metabolism ; *Vascular Endothelial Growth Factor A/metabolism ; *Nerve Regeneration/drug effects/physiology ; *Silicon/pharmacology ; *Peripheral Nerve Injuries/metabolism ; *Biofilms/drug effects ; *Rats, Sprague-Dawley ; Rats ; Male ; Disease Models, Animal ; MAP Kinase Signaling System/drug effects/physiology ; Sciatic Nerve/drug effects/injuries ; }, abstract = {Background: Injury of peripheral nerve capable of regeneration with much poorer prognosis affects people's life quality. The recovery of nerve function after transplantation for peripheral nerve injury remain a worldwide problem. Silicon-induced biofilms as vascularized biological conduits can promote nerve regeneration by encapsulating autologous or allogeneic nerve graft.Objective: We proposed to explore the effect of silicon-induced biofilms on nerves regeneration and whether the VEGF/VEGFR2/ERK pathway was involved in the present study.Methods: Biofilms around the transplanted nerves in peripheral nerve injury rats were induced by silicon. Vascularization and proteins related to VEGF/VEGFR2/ERK were measured. Pathology and morphology of nerves were investigated after encapsulating the transplanted nerves by silicon-induced biofilms.Results: Our results indicated that the biofilms induced by silicon for 6 weeks showed the most intensive vascularization and the optimal effect on nerve regeneration. Moreover, silicon-induced biofilms for 4, 6 and 8 weeks could significantly secrete VEGF with the highest content at week 6 after induction. VEGFR2, VEGF, p-VEGFR2, ERK1, ERK2, p-ERK1 and p-ERK2 were expressed in the biofilms. p-VEGFR2, p-ERK1 and p-ERK2 expression were different at each time point and significantly increased at week 6 compared with that at week 4 or week 8 which was consistent with that 6 week of was the optimum time for biofilms induction to improve the nerve repair after peripheral nerve injury.Conclusion: Our results suggested that combination of silicon-induced autologous vascularized biofilm and autologous transplantation may promote the repair of rat sciatic nerve defect quickly through VEGF/VEGFR2/ERK pathway.}, }
@article {pmid38720923, year = {2024}, author = {Ezeh, CK and Dibua, MEU}, title = {Anti-biofilm, drug delivery and cytotoxicity properties of dendrimers.}, journal = {ADMET &amp; DMPK}, volume = {12}, number = {2}, pages = {239-267}, pmid = {38720923}, issn = {1848-7718}, abstract = {BACKGROUND AND PURPOSE: Treatments using antimicrobial agents have faced many difficulties as a result of biofilm formation by pathogenic microorganisms. The biofilm matrix formed by these microorganisms prevents antimicrobial agents from penetrating the interior where they can exact their activity effectively. Additionally, extracellular polymeric molecules associated with biofilm surfaces can absorb antimicrobial compounds, lowering their bioavailability. This problem has resulted in the quest for alternative treatment protocols, and the development of nanomaterials and devices through nanotechnology has recently been on the rise.<br><br>RESEARCH APPROACH: The literature on dendrimers was searched for in databases such as Google Scholar, PubMed, and ScienceDirect.<br><br>KEY RESULTS: As a nanomaterial, dendrimers have found useful applications as a drug delivery vehicle for antimicrobial agents against biofilm-mediated infections to circumvent these defense mechanisms. The distinctive properties of dendrimers, such as multi-valency, biocompatibility, high water solubility, non-immunogenicity, and biofilm matrix-/cell membrane fusogenicity (ability to merge with intracellular membrane or other proteins), significantly increase the efficacy of antimicrobial agents and reduce the likelihood of recurring infections.<br><br>CONCLUSION: This review outlines the current state of dendrimer carriers for biofilm treatments, provides examples of their real-world uses, and examines potential drawbacks.}, }
@article {pmid38720728, year = {2024}, author = {Abdelrazek, HM and Ghozlan, HA and Sabry, SA and Abouelkheir, SS}, title = {Copper oxide nanoparticles (CuO-NPs) as a key player in the production of oil-based paint against biofilm and other activities.}, journal = {Heliyon}, volume = {10}, number = {9}, pages = {e29758}, pmid = {38720728}, issn = {2405-8440}, abstract = {Copper oxide nanoparticles are among the metal nanoparticles gaining popularity in many biotechnological fields, particularly in marine environments. Their antimicrobial and antibiofilm activities make them appealing to many researchers. Among the various methods of producing nanoparticles, biosynthesis is crucial. Thus, a large number of reports have been made about the microbiological manufacture of these nanoparticles by bacteria. Nevertheless, bio-production by means of the cell-free supernatant of marine bacteria is still in its primary phase. This is landmark research to look at how bacteria make a lot (14 g/L) of copper oxide nanoparticles (CuO-NPs) via the cell-free supernatant of Bacillus siamensis HS, their characterization, and their environmental and medical approaches. The biosynthesized nanoparticles were characterized using a UV-visible spectrum range that provides two maximum absorption peaks, one obtained at 400 nm and the other around 550-600 nm. Diffraction of X-rays (XRD) clarifies that the size of the NPs obtained was estimated to be 18 nm using Debye-Scherrer's equation. Scanning electron microscope-energy dispersive X-ray spectroscopy (SEM-EDX) displays 91.93 % copper oxide purity. The Transmission Electron Microscope (TEM) image proves that the particles have a spherical form and an average diameter of 6.54-8.60 nm. At the environmental level, nanoparticles incorporated into oil-based paint can be used as antibiofilm tools to diminish the biofilm formed on the submerged surface in the marine environment. In disease management, NPs can be used as a wound healing agent to reduce the wound gap size as well as an anti-tumour agent to control liver cancer cells (hepatoma cells (HepG2)).}, }
@article {pmid38719003, year = {2024}, author = {Wen, H and Zhang, Y and Mi, Z and Zhang, H and Sun, C and Liu, X and Fan, X}, title = {Rational design of PspAlgL to improve its thermostability and anti-biofilm activity against Pseudomonas aeruginosa.}, journal = {International journal of biological macromolecules}, volume = {269}, number = {Pt 1}, pages = {132084}, doi = {10.1016/j.ijbiomac.2024.132084}, pmid = {38719003}, issn = {1879-0003}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Pseudomonas aeruginosa/drug effects ; *Alginates/chemistry/pharmacology ; *Polysaccharide-Lyases/chemistry/metabolism ; *Anti-Bacterial Agents/pharmacology/chemistry ; Enzyme Stability ; Bacterial Proteins/chemistry/metabolism ; Temperature ; Glucuronic Acid/chemistry/pharmacology ; Models, Molecular ; }, abstract = {Pseudomonas aeruginosa biofilm enhances tolerance to antimicrobials and immune system defenses. Alginate is an important component of biofilm and a virulence factor of P. aeruginosa. The degradation of alginate by alginate lyases has come to serve as an adjunctive therapeutic strategy against P. aeruginosa biofilm, but poor stability of the enzyme limited this application. Thus, PspAlgL, an alginate lyase, can degrade acetylated alginate but has poor thermostability. The 3D structure of PspAlgL was predicted, and the thermostability of PspAlgL was rationally designed by GRAPE strategy, resulting in two variants with better stability. These variants, PspAlgLS270F/E311P and PspAlgLG291S/E311P, effectively degraded the alginate in biofilm. In addition, compared with PspAlgL, these variants were more efficient in inhibiting biofilm formation and degrading the established biofilm of P. aeruginosa PAO1, and they were also able to destroy the biofilm attached to catheters and to increase the sensitivity of P. aeruginosa to the antibiotic amikacin. This study provides one potential anti-biofilm agent for P. aeruginosa infection.}, }
@article {pmid38718953, year = {2024}, author = {Divya, M and Chen, J and Durán-Lara, EF and Kim, KS and Vijayakumar, S}, title = {Revolutionizing healthcare: Harnessing nano biotechnology with zinc oxide nanoparticles to combat biofilm and bacterial infections-A short review.}, journal = {Microbial pathogenesis}, volume = {191}, number = {}, pages = {106679}, doi = {10.1016/j.micpath.2024.106679}, pmid = {38718953}, issn = {1096-1208}, mesh = {*Biofilms/drug effects ; *Zinc Oxide/pharmacology/chemistry ; *Anti-Bacterial Agents/pharmacology ; *Metal Nanoparticles/chemistry ; Humans ; *Bacterial Infections/drug therapy/microbiology ; *Bacteria/drug effects ; Drug Resistance, Bacterial/drug effects ; Biotechnology ; }, abstract = {A crucial pathogenic mechanism in many bacterial diseases is the ability to create biofilms. Biofilms are suspected to play a role in over 80 % of microbial illnesses in humans. In light of the critical requirement for efficient management of bacterial infections, researchers have explored alternative techniques for treating bacterial disorders. One of the most promising ways to address this issue is through the development of long-lasting coatings with antibacterial properties. In recent years, antibacterial treatments based on metallic nanoparticles (NPs) have emerged as an effective strategy in the fight over bacterial drug resistance. Zinc oxide nanoparticles (ZnO-NPs) are the basis of a new composite coating material. This article begins with a brief overview of the mechanisms that underlie bacterial resistance to antimicrobial drugs. A detailed examination of the properties of metallic nanoparticles (NPs) and their potential use as antibacterial drugs for curing drug-sensitive and resistant bacteria follows. Furthermore, we assess metal nanoparticles (NPs) as powerful agents to fight against antibiotic-resistant bacteria and the growth of biofilm, and we look into their potential toxicological effects for the development of future medicines.}, }
@article {pmid38718531, year = {2024}, author = {Kang, S and Li, Q and Yang, Y and Lan, Y and Wang, X and Jiang, J and Han, M and Zhang, L and Wang, Q and Zhang, W}, title = {Effect of luminescent materials on the aquatic macrophyte Vallisneria natans and periphytic biofilm.}, journal = {Plant physiology and biochemistry : PPB}, volume = {211}, number = {}, pages = {108672}, doi = {10.1016/j.plaphy.2024.108672}, pmid = {38718531}, issn = {1873-2690}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Hydrocharitaceae/metabolism/microbiology ; Benzaldehydes/metabolism/pharmacology ; Photosynthesis/drug effects ; Luminescence ; Catalase/metabolism ; Peroxidase/metabolism ; Plant Leaves/metabolism ; Superoxide Dismutase/metabolism ; Luminescent Agents/metabolism ; }, abstract = {Luminescent materials can adjust the spectrum of light energy utilization by plants. However, current research on the effects of luminescent materials on aquatic plants and periphytic biofilms is limited. This study investigated the effects of the luminescent materials 4-(di-p-tolylamino) benzaldehyde-A (DTB-A) and 4-(di-p-tolylamino) benzaldehyde-M (DTB-M) on the submerged macrophyte Vallisneria natans (V. natans) and periphytic biofilm. Result demonstrated that low concentrations of DTB (0.1 μM) significantly promoted the growth and photosynthetic rate of V. natans. In terms of enzyme activity, exposure to a higher concentration of DTB (10 μM) increased the activities of peroxidase (POD), superoxide dismutase (SOD) and catalase (CAT). A combination of DTB-A and DTB-M treatment significantly changed the V. natans morphology and physiological characteristics, reducing the thickness of the cell wall and subsequently, promoting protein accumulation in leaves. There was no difference in the removal of ammonia or phosphate by V. natans at the 0.1 μM concentration, and the removal of ammonia and phosphate by V. natans decreased significantly as the concentration of luminescent material increased. A total of 3563 OTUs were identified in the biofilm community. The microbial community was dominated by Pseudomonas and Fusobacteria. Furthermore, results showed that an obvious decrease in diversity in the DTB-A and DTB-M mixed treatment group. In addition, the migratory aggregation of DTB molecules in plants was observed by fluorescence imaging. Overall, these findings extend our understanding of the mechanism of effect of luminescent materials on submerged macrophytes and their periphytic microorganisms.}, }
@article {pmid38718505, year = {2024}, author = {Liu, S and Zhang, Z and Zhao, C and Zhang, M and Han, F and Hao, J and Wang, X and Shan, X and Zhou, W}, title = {Nonlinear responses of biofilm bacteria to alkyl-chain length of parabens by DFT calculation.}, journal = {Journal of hazardous materials}, volume = {472}, number = {}, pages = {134460}, doi = {10.1016/j.jhazmat.2024.134460}, pmid = {38718505}, issn = {1873-3336}, mesh = {*Parabens/chemistry/toxicity ; *Biofilms/drug effects ; Bacteria/drug effects ; Density Functional Theory ; Quorum Sensing/drug effects ; }, abstract = {Parabens can particularly raise significant concerns regarding the disruption of microbial ecology due to their antimicrobial properties. However, the responses of biofilm bacteria to diverse parabens with different alkyl-chain length remains unclear. Here, theoretical calculations and bioinformatic analysis were performed to decipher the influence of parabens varying alkyl-chain lengths on the biofilm bacteria. Our results showed that the disturbances in bacterial community did not linearly response to the alkyl-chain length of parabens, and propylparaben (PrP), with median chain length, had more severe impact on bacterial community. Despite the fact that paraben lethality linearly increased with chain length, the PrP had a higher chemical reactions potential than parabens with shorter or longer alkyl-chain. The chemical reactions potential was critical in the nonlinear responses of bacterial community to alkyl-chain length of parabens. PrP could impose selective pressure to disturb the bacterial community, because it had a more profound contribution to deterministic assembly process. Furthermore, N-acyl-homoserine lactones was also significantly promoted under PrP exposure, confirming that PrP could affect the bacterial community by influencing the quorum-sensing system. Overall, our study reveals the nonlinear responses of bacterial communities to the alkyl-chain lengths of parabens and provides insightful perspectives for the better regulation of parabens. ENVIRONMENTAL IMPLICATION: Parabens are recognized as emerging organic pollutants, which specially raise great concerns due to their antimicrobial properties disturbing microbial ecology. However, few study have addressed the relationship between bacterial community responses and the molecular structural features of parabens with different alkyl-chain length. This investigation revealed nonlinear responses of the bacterial community to the alkyl-chain length of parabens through DFT calculation and bioinformatic analysis and identified the critical roles of chemical reactions potential in nonlinear responses of bacterial community. Our results benefit the precise evaluation of ecological hazards posed by parabens and provide useful insights for better regulation of parabens.}, }
@article {pmid38718417, year = {2024}, author = {Taşkın Kafa, AH and Aslan, R and Durna Daştan, S and Çeli K, C and Hasbek, M and Emi Noğlu, A}, title = {Molecular diversity of Klebsiella pneumoniae clinical isolates: antimicrobial resistance, virulence, and biofilm formation.}, journal = {Nucleosides, nucleotides &amp; nucleic acids}, volume = {}, number = {}, pages = {1-17}, doi = {10.1080/15257770.2024.2344741}, pmid = {38718417}, issn = {1532-2335}, abstract = {One of the mechanisms responsible for antibiotic resistance in Klebsiella pneumoniae is the enzymes produced by the bacteria; another important mechanism is the ability to form biofilm. In this study, antibiotic resistance, genes associated with virulence, and biofilm-forming properties of K. pneumoniae strains were investigated. A total of 100 K. pneumoniae isolates were obtained from different clinical samples identified by Matrix-Assisted Laser Desorption/Ionization time-of-flight Mass Spectrometry. Antimicrobial susceptibility testing was performed with the Phoenix 100 apparatus. The biofilm forming properties of strains were determined by the microtiter plate method. For molecular analysis, genes encoding the carbapenemase enzyme (blaOXA-48, blaNDM-1, blaIMP, and blaVIM) and biofilm-related genes (treC, luxS, mrkA, and wza) were investigated by polymerase chain reaction (PCR). While 76% of clinical isolates were resistant to three or more antimicrobials, 24% were classified as non-multidrug resistant (non-MDR). When biofilm-forming capacities of clinical isolates were tested, it was determined that the resistant-isolates produced 59.2% strong biofilm, and susceptible-isolates produced 12.5% strong biofilm. According to PCR results, carbapenemase genes were determined as follows: blaOXA-48-70%, blaNDM-49%, and blaKPC-19%, blaOXA-48/blaNDM/blaKPC-12%, blaOXA-48/blaNDM-26%, and blaOXA-48/blaKPC-4%. The biofilm-associated genes in bacterial isolates were determined as follows: luxS-98%, treC-94%, mrkA-88%, and wza-15%. In addition, Hierarchical Clustering Tree and Heatmap analysis revealed an association between isolates that lacks resistance genes and isolates lacks biofilm-formation related genes that were included in MDR or non-MDR classes. As a result, biofilm should be considered in the treatment of MDR infections, and therapy should be planned accordingly. In addition, pursuing the data and genes of antibiotic resistance is significant for combating resistance.}, }
@article {pmid38717992, year = {2024}, author = {Lencova, S and Stindlova, M and Havlickova, K and Jencova, V and Peroutka, V and Navratilova, K and Zdenkova, K and Stiborova, H and Hauzerova, S and Kostakova, EK and Jankovsky, O and Kejzlar, P and Lukas, D and Demnerova, K}, title = {Influence of Fiber Diameter of Polycaprolactone Nanofibrous Materials on Biofilm Formation and Retention of Bacterial Cells.}, journal = {ACS applied materials &amp; interfaces}, volume = {16}, number = {20}, pages = {25813-25824}, pmid = {38717992}, issn = {1944-8252}, mesh = {*Biofilms/drug effects ; *Polyesters/chemistry/pharmacology ; *Nanofibers/chemistry ; *Staphylococcus aureus/physiology/drug effects ; *Escherichia coli/physiology/drug effects ; }, abstract = {To develop microbiologically safe nanofibrous materials, it is crucial to understand their interactions with microbial cells. Current research indicates that the morphology of nanofibers, particularly the diameter of the fibers, may play a significant role in biofilm formation and retention. However, it has not yet been determined how the fiber diameter of poly-ε-caprolactone (PCL), one of the most widely used biopolymers, affects these microbial interactions. In this study, two nanofibrous materials electrospun from PCL (PCL45 and PCL80) with different fiber diameter and characteristic distance δ between fibers were compared in terms of their ability to support or inhibit bacterial biofilm formation and retain bacterial cells. Strains of Escherichia coli (ATCC 25922 and ATCC 8739) and Staphylococcus aureus (ATCC 25923 and ATCC 6538) were used as model bacteria. Biofilm formation rate and retention varied significantly between the E. coli and S. aureus strains (p < 0.05) for the tested nanomaterials. In general, PCL showed a lower tendency to be colonized by the tested bacteria compared to the control material (polystyrene). Fiber diameter did not influence the biofilm formation rate of S. aureus strains and E. coli 25922 (p > 0.05), but it did significantly impact the biofilm formation rate of E. coli 8739 and biofilm morphology formed by all of the tested bacterial strains. In PCL45, thick uniform biofilm layers were formed preferably on the surface, while in PCL80 smaller clusters formed preferably inside the structure. Further, fiber diameter significantly influenced the retention of bacterial cells of all the tested strains (p < 0.001). PCL45, with thin fibers (average fiber diameter of 376 nm), retained up to 7 log (CFU mL[-1]) of staphylococcal cells (100% retention). The overall results indicate PCL45's potential for further research and highlight the nanofibers' morphology influence on bacterial interactions and differences in bacterial strains' behavior in the presence of nanomaterials.}, }
@article {pmid38717096, year = {2024}, author = {Wang, Z and Zhang, X and Liu, Q and Hu, X and Mei, J and Zhou, J and Zhang, X and Xu, D and Zhu, W and Su, Z and Zhu, C}, title = {Balancing Bioresponsive Biofilm Eradication and Guided Tissue Repair via Pro-Efferocytosis and Bidirectional Pyroptosis Regulation during Implant Surgery.}, journal = {ACS nano}, volume = {18}, number = {20}, pages = {13196-13213}, doi = {10.1021/acsnano.4c02157}, pmid = {38717096}, issn = {1936-086X}, mesh = {*Biofilms/drug effects ; *Pyroptosis/drug effects ; Animals ; Mice ; Reactive Oxygen Species/metabolism ; Ferrocyanides/chemistry/pharmacology ; Prostheses and Implants ; Macrophages/metabolism/drug effects ; Anti-Bacterial Agents/pharmacology/chemistry ; Wound Healing/drug effects ; Humans ; Efferocytosis ; }, abstract = {There is an increasingly growing demand to balance tissue repair guidance and opportunistic infection (OI) inhibition in clinical implant surgery. Herein, we developed a nanoadjuvant for all-stage tissue repair guidance and biofilm-responsive OI eradication via in situ incorporating Cobaltiprotoporphyrin (CoPP) into Prussian blue (PB) to prepare PB-CoPP nanozymes (PCZs). Released CoPP possesses a pro-efferocytosis effect for eliminating apoptotic and progressing necrotic cells in tissue trauma, thus preventing secondary inflammation. Once OIs occur, PCZs with switchable nanocatalytic capacity can achieve bidirectional pyroptosis regulation. Once reaching the acidic biofilm microenvironment, PCZs possess peroxidase (POD)-like activity that can generate reactive oxygen species (ROS) to eradicate bacterial biofilms, especially when synergized with the photothermal effect. Furthermore, generated ROS can promote macrophage pyroptosis to secrete inflammatory cytokines and antimicrobial proteins for biofilm eradication in vivo. After eradicating the biofilm, PCZs possess catalase (CAT)-like activity in a neutral environment, which can scavenge ROS and inhibit macrophage pyroptosis, thereby improving the inflammatory microenvironment. Briefly, PCZs as nanoadjuvants feature the capability of all-stage tissue repair guidance and biofilm-responsive OI inhibition that can be routinely performed in all implant surgeries, providing a wide range of application prospects and commercial translational value.}, }
@article {pmid38717093, year = {2024}, author = {Hultqvist, LD and Andersen, JB and Nilsson, CM and Jansen, CU and Rybtke, M and Jakobsen, TH and Nielsen, TE and Qvortrup, K and Moser, C and Graz, M and Qvortrup, K and Tolker-Nielsen, T and Givskov, M}, title = {High efficacy treatment of murine Pseudomonas aeruginosa catheter-associated urinary tract infections using the c-di-GMP modulating anti-biofilm compound Disperazol in combination with ciprofloxacin.}, journal = {Antimicrobial agents and chemotherapy}, volume = {68}, number = {6}, pages = {e0148123}, pmid = {38717093}, issn = {1098-6596}, support = {2021-0300//Sygeforsikringen Danmark/ ; NNF18SA0034966//Novo Nordisk Fonden (NNF)/ ; 0161-00003//The Danish Innovation Foundation/ ; }, mesh = {Animals ; *Pseudomonas aeruginosa/drug effects ; *Urinary Tract Infections/drug therapy/microbiology ; *Biofilms/drug effects ; Mice ; *Anti-Bacterial Agents/pharmacology/therapeutic use ; *Ciprofloxacin/pharmacology ; *Pseudomonas Infections/drug therapy/microbiology ; *Cyclic GMP/metabolism/analogs &amp; derivatives ; Catheter-Related Infections/drug therapy/microbiology ; Female ; Microbial Sensitivity Tests ; }, abstract = {Persistent urinary tract infections (UTIs) in hospitalized patients constitute an important medical problem. It is estimated that 75% of nosocomial UTIs are associated with urinary tract catheters with P. aeruginosa being a species that forms biofilms on these catheters. These infections are highly resistant to standard-of-care antibiotics, and the effects of the host immune defenses, which allows for development of persistent infections. With antibiotics losing their efficacy, new treatment options against resilient infections, such as catheter-associated urinary tract infections (CAUTIs), are critically needed. Central to our anti-biofilm approach is the manipulation of the c-di-GMP signaling pathway in P. aeruginosa to switch bacteria from the protective biofilm to the unprotected planktonic mode of life. We recently identified a compound (H6-335-P1), that stimulates the c-di-GMP degrading activity of the P. aeruginosa BifA protein which plummets the intracellular c-di-GMP content and induces dispersal of P. aeruginosa biofilm bacteria into the planktonic state. In the present study, we formulated H6-335-P1 as a hydrochloride salt (Disperazol), which is water-soluble and facilitates delivery via injection or oral administration. Disperazol can work as a monotherapy, but we observed a 100-fold improvement in efficacy when treating murine P. aeruginosa CAUTIs with a Disperazol/ciprofloxacin combination. Biologically active Disperazol reached the bladder 30 min after oral administration. Our study provides proof of concept that Disperazol can be used in combination with a relevant antibiotic for effective treatment of CAUTIs.}, }
@article {pmid38714243, year = {2024}, author = {Miranda, ML and Danelon, M and Delbem, ACB and Kopp, W and Nunes, GP and Brighenti, FL}, title = {Enhanced anti-biofilm and anti-caries potential of arginine combined with calcium glycerophosphate and fluoride.}, journal = {Journal of dentistry}, volume = {146}, number = {}, pages = {105039}, doi = {10.1016/j.jdent.2024.105039}, pmid = {38714243}, issn = {1879-176X}, mesh = {*Arginine/pharmacology ; *Biofilms/drug effects ; Cattle ; Animals ; *Dental Enamel/drug effects/microbiology ; *Streptococcus mutans/drug effects ; *Fluorides/pharmacology ; *Glycerophosphates/pharmacology ; *Cariostatic Agents/pharmacology ; *Saliva/microbiology ; Hydrogen-Ion Concentration ; *Dental Caries/prevention &amp; control/microbiology ; *Microbial Viability/drug effects ; Hardness ; Humans ; Tooth Demineralization/prevention &amp; control/microbiology ; Surface Properties ; }, abstract = {OBJECTIVE: The aim of this work was to evaluate the antibiofilm and anticaries properties of the association of arginine (Arg) with calcium glycerophosphate (CaGP) and fluoride (F).<br><br>METHODS: An active attachment, polymicrobial biofilm model obtained from saliva and bovine teeth discs were used. After the initial biofilm growth period, the enamel discs were transferred to culture medium. The treatment solutions were added to the culture media to achieve the desired final concentration. The following groups were used: negative control (Control); F (110 ppm F); CaGP (0.05 %); Arg (0.8 %) and their associations (F + CaGP; Arg + F; Arg + CaGP; Arg +F + CaGP). The following analyses were carried out: bacterial viability (total bacteria, aciduric bacteria and mutans streptococci), pH assessment of the spent culture medium, dry weight quantification, evaluation of surface hardness loss (%SH) and subsurface mineral content. Normality and homoscedasticity were tested (Shapiro-Wilk and Levene's test) and the following tests were applied: two-way ANOVA (acidogenicity), Kruskall-Wallis (microbial viability) and one way ANOVA (dry weight, %SH, mineral content).<br><br>RESULTS: The association Arg + F + CaGP resulted in the lowest surface hardness loss in tooth enamel (-10.9 &#xb1; 2.3 %; p < 0.05). Arg +F + CaGP exhibited highest values of subsurface mineral content (10.1 &#xb1; 2.9 gHAP/cm[3]) in comparison to Control and F (p < 0.05). In comparison to Control and F, Arg +F + CaGP promoted the highest reduction in aciduric bacteria and mutans streptococci (5.7 &#xb1; 0.4; 4.4 &#xb1; 0.5 logCFU/mL, p < 0.05).<br><br>CONCLUSIONS: The Arg-F-Ca association demonstrated to be the most effective combination in protecting the loss of surface hardness and subsurface mineral content, in addition to controlling important virulence factors of the cariogenic biofilm.<br><br>CLINICAL SIGNIFICANCE: Our findings provide evidence that the Arg-F-Ca association showed an additive effect, particularly concerning protection against enamel demineralization. The combination of these compounds may be a strategy for patients at high risk of caries.}, }
@article {pmid38713935, year = {2024}, author = {Niu, C and Ying, Y and Zhao, J and Zheng, M and Guo, J and Yuan, Z and Hu, S and Liu, T}, title = {Superior mainstream partial nitritation in an acidic membrane-aerated biofilm reactor.}, journal = {Water research}, volume = {257}, number = {}, pages = {121692}, doi = {10.1016/j.watres.2024.121692}, pmid = {38713935}, issn = {1879-2448}, mesh = {*Bioreactors ; *Biofilms ; Waste Disposal, Fluid/methods ; Ammonia/metabolism ; Wastewater/chemistry ; Oxidation-Reduction ; Nitrites/metabolism ; Nitrogen ; Hydrogen-Ion Concentration ; Bacteria/metabolism ; Membranes, Artificial ; }, abstract = {Shortcut nitrogen removal holds significant economic appeal for mainstream wastewater treatment. Nevertheless, it is too difficult to achieve the stable suppression of nitrite-oxidizing bacteria (NOB), and simultaneously maintain the activity of ammonia-oxidizing bacteria (AOB). This study proposes to overcome this challenge by employing the novel acid-tolerant AOB, namely "Candidatus Nitrosoglobus", in a membrane-aerated biofilm reactor (MABR). Superior partial nitritation was demonstrated in low-strength wastewater from two aspects. First, the long-term operation (256 days) under the acidic pH range of 5.0 to 5.2 showed the successful NOB washout by the in situ free nitrous acid (FNA) of approximately 1 mg N/L. This was evidenced by the stable nitrite accumulation ratio (NAR) close to 100 % and the disappearance of NOB shown by 16S rRNA gene amplicon sequencing and fluorescence in situ hybridization. Second, oxygen was sufficiently supplied in the MABR, leading to an unprecedentedly high ammonia oxidation rate (AOR) at 2.4 ± 0.1 kg N/(m[3] d) at a short hydraulic retention time (HRT) of a mere 30 min. Due to the counter diffusion of substrates, the present acidic MABR displayed a significantly higher apparent oxygen affinity (0.36 ± 0.03 mg O2/L), a marginally lower apparent ammonia affinity (14.9 ± 1.9 mg N/L), and a heightened sensitivity to FNA and pH variations, compared with counterparts determined by flocculant acid-tolerant AOB. Beyond supporting the potential application of shortcut nitrogen removal in mainstream wastewater, this study also offers the attractive prospect of intensifying wastewater treatment by markedly reducing the HRT of the aerobic unit.}, }
@article {pmid38711646, year = {2024}, author = {Lordelo, R and Branco, R and Gama, F and Morais, PV}, title = {Assessment of antimicrobial resistance, biofilm formation, and surface modification potential in hospital strains of Pseudomonas aeruginosa and Klebsiella pneumoniae.}, journal = {Heliyon}, volume = {10}, number = {9}, pages = {e30464}, pmid = {38711646}, issn = {2405-8440}, abstract = {The occurrence of healthcare-associated infections is a multifactorial phenomenon related to hospital space contamination by bacteria. The ESKAPE group, specifically Pseudomonas aeruginosa and Klebsiella pneumoniae, play a relevant role in the occurrence of these infections. Therefore, comprehensive research is needed to identify characteristics that justify the prevalence of these species in the healthcare environment. In this line, the study aimed to determine the antimicrobial resistance, biofilm formation, and the potential for polymer degradation in a collection of 33 P. aeruginosa strains and 2 K. pneumoniae strains sampled from various equipment and non-critical surfaces in a Portuguese hospital. Antimicrobial susceptibility tests revealed that none of the strains was categorized as multidrug-resistant (non-MDR). An assessment of their biofilm-forming capabilities indicated that 97 % of the strains exhibited biofilm-producing characteristics. Notably, within this group, the majority of P. aeruginosa and half of K. pneumoniae strains were classified as strong biofilm producers. Furthermore, the strains were evaluated for their potential to cause damage or change medical devices, namely infusion sets, nasal cannula, and urinary catheters. Three P. aeruginosa strains, two strong and one moderate biofilm producers, showed the highest ability to modify surfaces of the nasal cannula and infusion sets. Additionally, the Chi-square test revealed a statistically significant relationship between the presence of P. aeruginosa strains and the water accession spots. In conclusion, this work suggests that bacteria from this group hold a significant ability to grow in the healthcare environment through the degradation of non-critical materials. This suggests a potential concern for the persistence and proliferation of these organisms in hospital environments, emphasizing the importance of robust infection control measures to mitigate the risks associated with bacterial growth on such surfaces.}, }
@article {pmid38711289, year = {2024}, author = {Cruz, PD and Wargowsky, R and Gonzalez-Almada, A and Sifontes, EP and Shaykhinurov, E and Jaatinen, K and Jepson, T and Lafleur, JE and Yamane, D and Perkins, J and Pasquale, M and Giang, B and McHarg, M and Falk, Z and McCaffrey, TA}, title = {Blood RNA Biomarkers Identify Bacterial and Biofilm Coinfections in COVID-19 Intensive Care Patients.}, journal = {Journal of intensive care medicine}, volume = {39}, number = {11}, pages = {1071-1082}, doi = {10.1177/08850666241251743}, pmid = {38711289}, issn = {1525-1489}, mesh = {Humans ; *Biofilms/growth &amp; development ; *COVID-19/blood/complications/diagnosis ; *Biomarkers/blood ; Male ; Female ; Middle Aged ; *Coinfection/blood/microbiology ; *SARS-CoV-2 ; Aged ; Intensive Care Units ; Bacterial Infections/blood/diagnosis ; Adult ; RNA/blood ; Alkaline Phosphatase/blood ; Critical Care ; }, abstract = {Purpose: Secondary opportunistic coinfections are a significant contributor to morbidity and mortality in intensive care unit (ICU) patients, but can be difficult to identify. Presently, new blood RNA biomarkers were tested in ICU patients to diagnose viral, bacterial, and biofilm coinfections. Methods: COVID-19 ICU patients had whole blood drawn in RNA preservative and stored at -80°C. Controls and subclinical infections were also studied. Droplet digital polymerase chain reaction (ddPCR) quantified 6 RNA biomarkers of host neutrophil activation to bacterial (DEFA1), biofilm (alkaline phosphatase [ALPL], IL8RB/CXCR2), and viral infections (IFI27, RSAD2). Viral titer in blood was measured by ddPCR for SARS-CoV2 (SCV2). Results: RNA biomarkers were elevated in ICU patients relative to controls. DEFA1 and ALPL RNA were significantly higher in severe versus incidental/moderate cases. SOFA score was correlated with white blood cell count (0.42), platelet count (-0.41), creatinine (0.38), and lactate dehydrogenase (0.31). ALPL RNA (0.59) showed the best correlation with SOFA score. IFI27 (0.52) and RSAD2 (0.38) were positively correlated with SCV2 viral titer. Overall, 57.8% of COVID-19 patients had a positive RNA biomarker for bacterial or biofilm infection. Conclusions: RNA biomarkers of host neutrophil activation indicate the presence of bacterial and biofilm coinfections in most COVID-19 patients. Recognizing coinfections may help to guide the treatment of ICU patients.}, }
@article {pmid38709077, year = {2024}, author = {Poirier, S and Jean-Pierre, F}, title = {Growing a Cystic Fibrosis-Relevant Polymicrobial Biofilm to Probe Community Phenotypes.}, journal = {Journal of visualized experiments : JoVE}, volume = {}, number = {206}, pages = {}, doi = {10.3791/66785}, pmid = {38709077}, issn = {1940-087X}, mesh = {*Cystic Fibrosis/microbiology ; *Biofilms/growth &amp; development ; Humans ; *Phenotype ; Pseudomonas aeruginosa/physiology ; Staphylococcus aureus/physiology/genetics ; Microbiota/physiology ; Streptococcus sanguis/physiology ; Prevotella melaninogenica/genetics ; }, abstract = {Most in vitro models lack the capacity to fully probe bacterial phenotypes emerging from the complex interactions observed in real-life environments. This is particularly true in the context of hard-to-treat, chronic, and polymicrobial biofilm-based infections detected in the airways of individuals living with cystic fibrosis (CF), a multiorgan genetic disease. While multiple microbiome studies have defined the microbial compositions detected in the airway of people with CF (pwCF), no in vitro models thus far have fully integrated critical CF-relevant lung features. Therefore, a significant knowledge gap exists in the capacity to investigate the mechanisms driving the pathogenesis of mixed species CF lung infections. Here, we describe a recently developed four-species microbial community model, including Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus sanguinis, and Prevotella melaninogenica grown in CF-like conditions. Through the utilization of this system, clinically relevant phenotypes such as antimicrobial recalcitrance of several pathogens were observed and explored at the molecular level. The usefulness of this in vitro model resides in its standardized workflow that can facilitate the study of interspecies interactions in the context of chronic CF lung infections.}, }
@article {pmid38708178, year = {2024}, author = {Nafee, N and Gaber, DM and Abouelfetouh, A and Alseqely, M and Empting, M and Schneider, M}, title = {Enzyme-Linked Lipid Nanocarriers for Coping Pseudomonal Pulmonary Infection. Would Nanocarriers Complement Biofilm Disruption or Pave Its Road?.}, journal = {International journal of nanomedicine}, volume = {19}, number = {}, pages = {3861-3890}, pmid = {38708178}, issn = {1178-2013}, mesh = {*Biofilms/drug effects ; *Pseudomonas aeruginosa/drug effects/physiology ; Humans ; *Pseudomonas Infections/drug therapy ; *Nanoparticles/chemistry ; *Chitosan/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry/pharmacokinetics ; Drug Carriers/chemistry ; Cystic Fibrosis/drug therapy/microbiology ; Lipids/chemistry/pharmacology ; Quorum Sensing/drug effects ; A549 Cells ; Alginates/chemistry ; *Liposomes ; }, abstract = {INTRODUCTION: Cystic fibrosis (CF) is associated with pulmonary Pseudomonas aeruginosa infections persistent to antibiotics.<br><br>METHODS: To eradicate pseudomonal biofilms, solid lipid nanoparticles (SLNs) loaded with quorum-sensing-inhibitor (QSI, disrupting bacterial crosstalk), coated with chitosan (CS, improving internalization) and immobilized with alginate lyase (AL, destroying alginate biofilms) were developed.<br><br>RESULTS: SLNs (140-205 nm) showed prolonged release of QSI with no sign of acute toxicity to A549 and Calu-3 cells. The CS coating improved uptake, whereas immobilized-AL ensured >1.5-fold higher uptake and doubled SLN diffusion across the artificial biofilm sputum model. Respirable microparticles comprising SLNs in carbohydrate matrix elicited aerodynamic diameters MMAD (3.54, 2.48 &#xb5;m) and fine-particle-fraction FPF (65, 48%) for anionic and cationic SLNs, respectively. The antimicrobial and/or antibiofilm activity of SLNs was explored in Pseudomonas aeruginosa reference mucoid/nonmucoid strains as well as clinical isolates. The full growth inhibition of planktonic bacteria was dependent on SLN type, concentration, growth medium, and strain. OD measurements and live/dead staining proved that anionic SLNs efficiently ceased biofilm formation and eradicated established biofilms, whereas cationic SLNs unexpectedly promoted biofilm progression. AL immobilization increased biofilm vulnerability; instead, CS coating increased biofilm formation confirmed by 3D-time lapse confocal imaging. Incubation of SLNs with mature biofilms of P. aeruginosa isolates increased biofilm density by an average of 1.5-fold. CLSM further confirmed the binding and uptake of the labeled SLNs in P. aeruginosa biofilms. Considerable uptake of CS-coated SLNs in non-mucoid strains could be observed presumably due to interaction of chitosan with LPS glycolipids in the outer cell membrane of P. aeruginosa.<br><br>CONCLUSION: The biofilm-destructive potential of QSI/SLNs/AL inhalation is promising for site-specific biofilm-targeted interventional CF therapy. Nevertheless, the intrinsic/extrinsic fundamentals of nanocarrier-biofilm interactions require further investigation.}, }
@article {pmid38706985, year = {2024}, author = {Huijboom, L and Rashtchi, P and Tempelaars, M and Boeren, S and van der Linden, E and Habibi, M and Abee, T}, title = {Phenotypic and proteomic differences in biofilm formation of two Lactiplantibacillus plantarum strains in static and dynamic flow environments.}, journal = {Biofilm}, volume = {7}, number = {}, pages = {100197}, pmid = {38706985}, issn = {2590-2075}, abstract = {Lactiplantibacillus plantarum is a Gram-positive non-motile bacterium capable of producing biofilms that contribute to the colonization of surfaces in a range of different environments. In this study, we compared two strains, WCFS1 and CIP104448, in their ability to produce biofilms in static and dynamic (flow) environments using an in-house designed flow setup. This flow setup enables us to impose a non-uniform flow velocity profile across the well. Biofilm formation occurred at the bottom of the well for both strains, under static and flow conditions, where in the latter condition, CIP104448 also showed increased biofilm formation at the walls of the well in line with the higher hydrophobicity of the cells and the increased initial attachment efficacy compared to WCFS1. Fluorescence and scanning electron microscopy showed open 3D structured biofilms formed under flow conditions, containing live cells and ∼30 % damaged/dead cells for CIP104448, whereas the WCFS1 biofilm showed live cells closely packed together. Comparative proteome analysis revealed minimal changes between planktonic and static biofilm cells of the respective strains suggesting that biofilm formation within 24 h is merely a passive process. Notably, observed proteome changes in WCFS1 and CIP104448 flow biofilm cells indicated similar and unique responses including changes in metabolic activity, redox/electron transfer and cell division proteins for both strains, and myo-inositol production for WCFS1 and oxidative stress response and DNA damage repair for CIP104448 uniquely. Exposure to DNase and protease treatments as well as lethal concentrations of peracetic acid showed highest resistance of flow biofilms. For the latter, CIP104448 flow biofilm even maintained its high disinfectant resistance after dispersal from the bottom and from the walls of the well. Combining all results highlights that L. plantarum biofilm structure and matrix, and physiological state and stress resistance of cells is strain dependent and strongly affected under flow conditions. It is concluded that consideration of effects of flow on biofilm formation is essential to better understand biofilm formation in different settings, including food processing environments.}, }
@article {pmid38706006, year = {2024}, author = {Liew, KJ and Shahar, S and Shamsir, MS and Shaharuddin, NB and Liang, CH and Chan, KG and Pointing, SB and Sani, RK and Goh, KM}, title = {Integrating multi-platform assembly to recover MAGs from hot spring biofilms: insights into microbial diversity, biofilm formation, and carbohydrate degradation.}, journal = {Environmental microbiome}, volume = {19}, number = {1}, pages = {29}, pmid = {38706006}, issn = {2524-6372}, support = {FRGS/1/2023/STG02/UTM/02/1, FRGS/1/2019/STG03/UTM/02/1, FRGS/1/2019/STG04/UTM/02/4//Malaysia Fundamental Research Grant Scheme (FRGS)/ ; FRGS/1/2023/STG02/UTM/02/1, FRGS/1/2019/STG03/UTM/02/1, FRGS/1/2019/STG04/UTM/02/4//Malaysia Fundamental Research Grant Scheme (FRGS)/ ; FRGS/1/2023/STG02/UTM/02/1, FRGS/1/2019/STG03/UTM/02/1, FRGS/1/2019/STG04/UTM/02/4//Malaysia Fundamental Research Grant Scheme (FRGS)/ ; FRGS/1/2023/STG02/UTM/02/1, FRGS/1/2019/STG03/UTM/02/1, FRGS/1/2019/STG04/UTM/02/4//Malaysia Fundamental Research Grant Scheme (FRGS)/ ; FRGS/1/2023/STG02/UTM/02/1, FRGS/1/2019/STG03/UTM/02/1, FRGS/1/2019/STG04/UTM/02/4//Malaysia Fundamental Research Grant Scheme (FRGS)/ ; 4J549//UTM QuickWin grant/ ; 4J549//UTM QuickWin grant/ ; T2EP30123-0028//Singapore Ministry of Education ARC Tier 2 fund/ ; 1736255, 1849206, and 1920954//National Science Foundation/ ; }, abstract = {BACKGROUND: Hot spring biofilms provide a window into the survival strategies of microbial communities in extreme environments and offer potential for biotechnological applications. This study focused on green and brown biofilms thriving on submerged plant litter within the Sungai Klah hot spring in Malaysia, characterised by temperatures of 58-74 °C. Using Illumina shotgun metagenomics and Nanopore ligation sequencing, we investigated the microbial diversity and functional potential of metagenome-assembled genomes (MAGs) with specific focus on biofilm formation, heat stress response, and carbohydrate catabolism.<br><br>RESULTS: Leveraging the power of both Illumina short-reads and Nanopore long-reads, we employed an Illumina-Nanopore hybrid assembly approach to construct MAGs with enhanced quality. The dereplication process, facilitated by the dRep tool, validated the efficiency of the hybrid assembly, yielding MAGs that reflected the intricate microbial diversity of these extreme ecosystems. The comprehensive analysis of these MAGs uncovered intriguing insights into the survival strategies of thermophilic taxa in the hot spring biofilms. Moreover, we examined the plant litter degradation potential within the biofilms, shedding light on the participation of diverse microbial taxa in the breakdown of starch, cellulose, and hemicellulose. We highlight that Chloroflexota and Armatimonadota MAGs exhibited a wide array of glycosyl hydrolases targeting various carbohydrate substrates, underscoring their metabolic versatility in utilisation of carbohydrates at elevated temperatures.<br><br>CONCLUSIONS: This study advances understanding of microbial ecology on plant litter under elevated temperature by revealing the functional adaptation of MAGs from hot spring biofilms. In addition, our findings highlight potential for biotechnology application through identification of thermophilic lignocellulose-degrading enzymes. By demonstrating the efficiency of hybrid assembly utilising Illumina-Nanopore reads, we highlight the value of combining multiple sequencing methods for a more thorough exploration of complex microbial communities.}, }
@article {pmid38705960, year = {2024}, author = {Kanwar, K and Sharma, D and Singh, H and Pal, M and Bandhu, R and Azmi, W}, title = {In vitro effects of alginate lyase SG4 + produced by Paenibacillus lautus alone and combined with antibiotics on biofilm formation by mucoid Pseudomonas aeruginosa.}, journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]}, volume = {55}, number = {2}, pages = {1189-1203}, pmid = {38705960}, issn = {1678-4405}, mesh = {*Pseudomonas aeruginosa/drug effects/enzymology/genetics ; *Biofilms/drug effects/growth &amp; development ; *Polysaccharide-Lyases/metabolism/genetics ; *Anti-Bacterial Agents/pharmacology ; *Paenibacillus/genetics/enzymology/drug effects ; Gentamicins/pharmacology ; Amikacin/pharmacology ; Fermentation ; Microbial Sensitivity Tests ; Bacterial Proteins/metabolism/genetics ; Alginates/metabolism ; }, abstract = {Alginate is a major extra polymeric substance in the biofilm formed by mucoid Pseudomonas aeruginosa. It is the main proven perpetrator of lung infections in patients suffering from cystic fibrosis. Alginate lyases are very important in the treatment of cystic fibrosis. This study evaluated the role of standalone and in conjugation, effect of alginate lyase of SG4 + isolated from Paenibacillus lautus in enhancing in vitro bactericidal activity of gentamicin and amikacin on mucoid P. aeruginosa. Using Response Surface Methodology (RSM) alginate lyase SG4 + production was optimized in shake flask and there 8.49-fold enhancement in enzyme production. In fermenter, maximum growth (10.15 mg/ml) and alginate lyase (1.46 International Units) production, 1.71-fold was increased using Central Composite Design (CCD). Further, fermentation time was reduced from 48 to 20 h. To the best of our knowledge this is the first report in which CCD was used for fermenter studies to optimize alginate lyase production. The Km and Vmax of purified enzyme were found to be 2.7 mg/ml and 0.84 mol/ml-min, respectively. The half-life (t 1/2) of purified alginate lyase SG4 + at 37 °C was 180 min. Alginate lyase SG4 + in combination with gentamicin and amikacin eradiated 48.4- 52.3% and 58- 64.6%, alginate biofilm formed by P. aeruginosa strains, respectively. The study proves that alginate lyase SG4 + has excellent exopolysaccharide disintegrating ability and may be useful in development of potent therapeutic agent to treat P. aeruginosa biofilms.}, }
@article {pmid38704559, year = {2024}, author = {Esfandiary, MA and Khosravi, AR and Asadi, S and Nikaein, D and Hassan, J and Sharifzadeh, A}, title = {Antimicrobial and anti-biofilm properties of oleuropein against Escherichia coli and fluconazole-resistant isolates of Candida albicans and Candida glabrata.}, journal = {BMC microbiology}, volume = {24}, number = {1}, pages = {154}, pmid = {38704559}, issn = {1471-2180}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Iridoid Glucosides/pharmacology ; *Microbial Sensitivity Tests ; *Candida glabrata/drug effects/physiology/genetics ; *Candida albicans/drug effects/genetics/physiology ; *Escherichia coli/drug effects/genetics ; *Iridoids/pharmacology ; *Fluconazole/pharmacology ; *Antifungal Agents/pharmacology ; Drug Resistance, Fungal ; Anti-Bacterial Agents/pharmacology ; Microscopy, Electron, Scanning ; }, abstract = {BACKGROUND: Side effects associated with antimicrobial drugs, as well as their high cost, have prompted a search for low-cost herbal medicinal substances with fewer side effects. These substances can be used as supplements to medicine or to strengthen their effects. The current study investigated the effect of oleuropein on the inhibition of fungal and bacterial biofilm in-vitro and at the molecular level.<br><br>MATERIALS AND METHODS: In this experimental study, antimicrobial properties were evaluated using microbroth dilution method. The effect of oleuropein on the formation and eradication of biofilm was assessed on 96-well flat bottom microtiter plates and their effects were observed through scanning electron microscopy (SEM). Its effect on key genes (Hwp1, Als3, Epa1, Epa6, LuxS, Pfs) involved in biofilm formation was investigated using the quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR) method.<br><br>RESULTS: The minimum inhibitory concentration (MIC) and minimum fungicidal/bactericidal concentration (MFC/MBC) for oleuropein were found to be 65&#x2009;mg/ml and 130&#x2009;mg/ml, respectively. Oleuropein significantly inhibited biofilm formation at MIC/2 (32.5&#x2009;mg/ml), MIC/4 (16.25&#x2009;mg/ml), MIC/8 (8.125&#x2009;mg/ml) and MIC/16 (4.062&#x2009;mg/ml) (p&#x2009;<&#x2009;0.0001). The anti-biofilm effect of oleuropein was confirmed by SEM. RT-qPCR indicated significant down regulation of expression genes involved in biofilm formation in Candida albicans (Hwp1, Als3) and Candida glabrata (Epa1, Epa6) as well as Escherichia coli (LuxS, Pfs) genes after culture with a MIC/2 of oleuropein (p&#x2009;<&#x2009;0.0001).<br><br>CONCLUSIONS: The results indicate that oleuropein has antifungal and antibacterial properties that enable it to inhibit or destroy the formation of fungal and bacterial biofilm.}, }
@article {pmid38703685, year = {2024}, author = {Wang, H and Zhou, Q}, title = {Bioelectrochemical anaerobic digestion mitigates microplastic pollution and promotes methane recovery of wastewater treatment in biofilm system.}, journal = {Journal of hazardous materials}, volume = {472}, number = {}, pages = {134488}, doi = {10.1016/j.jhazmat.2024.134488}, pmid = {38703685}, issn = {1873-3336}, mesh = {*Biofilms ; *Wastewater/chemistry ; *Methane/metabolism ; Anaerobiosis ; *Water Pollutants, Chemical/metabolism ; *Microplastics ; Bioreactors ; Waste Disposal, Fluid/methods ; Electrochemical Techniques ; Polyethylene/metabolism/chemistry ; }, abstract = {Bioelectrochemical systems (BES) offer significant potential for treating refractory waste and recovering bioenergy. However, their ability to mitigate microplastic pollution in wastewater remains unexplored. This study showed that BES facilitated the treatment of polyethylene (PE), polyvinyl chloride (PVC), and Mix (PE+PVC) microplastic wastewater and the methane recovery (40.61%, 20.02%, 21.19%, respectively). The lactate dehydrogenase (LDH), adenosine triphosphate (ATP), cytochrome c, and nicotinamide adenine dinucleotide (NADH/NAD+) ratios were elevated with electrical stimulation. Moreover, the applied voltage improved the polysaccharides content of the extracellular polymeric substances (EPS) in the PE-BES but decreased in PVC-BES, while the proteins showed the opposite trend. Metatranscriptomic sequencing showed that the abundance of fermentation bacteria, acetogens, electrogens, and methanogens was greatly enhanced by applying voltage, especially at the anode. Methane metabolism was dominated by the acetoclastic methanogenic pathway, with the applied voltage promoting the enrichment of Methanothrix, resulting in the direct conversion of acetate to acetyl-CoA via acetate-CoA ligase (EC: 6.2.1.1), and increased metabolic activity in the anode. Moreover, applied voltage greatly boosted the function genes expression level related to energy metabolism, tricarboxylic acid (TCA) cycle, electron transport, and transporters on the anode biofilm. Overall, these results demonstrate that BES can mitigate microplastic pollution during wastewater treatment.}, }
@article {pmid38703635, year = {2024}, author = {Kwiecińska-Piróg, J and Chomont, K and Fydrych, D and Stawarz, J and Bogiel, T and Przekwas, J and Gospodarek-Komkowska, E}, title = {How xylitol, gluten, and lactose change human gut microbiota Escherichia coli and Lactobacillus rhamnosus GG biofilm.}, journal = {Nutrition (Burbank, Los Angeles County, Calif.)}, volume = {124}, number = {}, pages = {112446}, doi = {10.1016/j.nut.2024.112446}, pmid = {38703635}, issn = {1873-1244}, mesh = {*Biofilms/drug effects ; *Xylitol/pharmacology ; Humans ; *Lactose ; *Lacticaseibacillus rhamnosus/physiology ; *Gastrointestinal Microbiome/physiology/drug effects ; *Escherichia coli/drug effects ; *Probiotics/pharmacology ; *Glutens ; }, abstract = {OBJECTIVE: The human gut microbiota is composed of many viruses, bacteria, and fungi. Escherichia coli representatives are facultative anaerobic bacteria in the colon that play a crucial role in the metabolism of lactose, vitamin synthesis, and immune system modulation. E. coli forms a biofilm on the epithelial cell surface of the intestine that can be modified by diet compounds, i.e., gluten, xylitol, lactose, and probiotics.<br><br>METHODS: In the present study, the impact of probiotic-derived Lactobacillus rhamnosus GG strain on non-pathogenic E. coli biofilm was examined. The mono- and multispecies biofilm was also treated with gluten, xylitol, and lactose. We used 96-well plates to obtain biofilm growth. Biofilm was stained using crystal violet. To evaluate the type of interaction in mono- and multispecies biofilm, a new formula was introduced: biofilm interaction ratio index (BIRI). To describe the impact of nutrients on biofilm formation, the biofilm formation impact ratio (BFIR) was calculated.<br><br>RESULTS: The biofilms formed by both examined species are stronger than in monocultures. All the BIRI values were above 3.0. It was found that the monospecies biofilm of L. rhamnosus is strongly inhibited by gluten (84.5%) and the monospecies biofilm of E. coli by xylitol (85.5%). The mixed biofilm is inhibited by lactose (78.8%) and gluten (90.6%).<br><br>CONCLUSION: The relations between bacteria in the mixed biofilm led to changes in biofilm formation by E. coli and L. rhamnosus GG. Probiotics might be helpful in rebuilding the gut microbiota after broad spectrum antibiotic therapy, but only if gluten and lactose are excluded from diet.}, }
@article {pmid38702839, year = {2024}, author = {Paulino, S and Petek, S and Le Strat, Y and Bourgougnon, N and Le Blay, G}, title = {Cultivable epiphytic bacteria of the Chlorophyta Ulva sp.: diversity, antibacterial, and biofilm-modulating activities.}, journal = {Journal of applied microbiology}, volume = {135}, number = {5}, pages = {}, doi = {10.1093/jambio/lxae099}, pmid = {38702839}, issn = {1365-2672}, support = {ANR-17-EURE-0015//ISblue/ ; //Universit&#xe9; Bretagne Sud/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Ulva/microbiology ; *Anti-Bacterial Agents/pharmacology ; *RNA, Ribosomal, 16S/genetics ; *Bacteria/genetics/classification/isolation &amp; purification/drug effects ; Microbiota ; Phylogeny ; Biodiversity ; Seaweed/microbiology ; }, abstract = {AIMS: Macroalgae harbor a rich epiphytic microbiota that plays a crucial role in algal morphogenesis and defense mechanisms. This study aims to isolate epiphytic cultivable microbiota from Ulva sp. surfaces. Various culture media were employed to evaluate a wide range of cultivable microbiota. Our objective was to assess the antibacterial and biofilm-modulating activities of supernatants from isolated bacteria.<br><br>METHODS AND RESULTS: Sixty-nine bacterial isolates from Ulva sp. were identified based on 16S rRNA gene sequencing. Their antibacterial activity and biofilm modulation potential were screened against three target marine bacteria: 45%, mostly affiliated with Gammaproteobacteria and mainly grown on diluted R2A medium (R2Ad), showed strong antibacterial activity, while 18% had a significant impact on biofilm modulation. Molecular network analysis was carried out on four bioactive bacterial supernatants, revealing new molecules potentially responsible for their activities.<br><br>CONCLUSION: R2Ad offered the greatest diversity and proportion of active isolates. The molecular network approach holds promise for both identifying bacterial isolates based on their molecular production and characterizing antibacterial and biofilm-modulating activities.}, }
@article {pmid38702622, year = {2024}, author = {Alabssawy, AN and Abu-Elghait, M and Azab, AM and Khalaf-Allah, HMM and Ashry, AS and Ali, AOM and Sabra, AAA and Salem, SS}, title = {Hindering the biofilm of microbial pathogens and cancer cell lines development using silver nanoparticles synthesized by epidermal mucus proteins from Clarias gariepinus.}, journal = {BMC biotechnology}, volume = {24}, number = {1}, pages = {28}, pmid = {38702622}, issn = {1472-6750}, mesh = {*Metal Nanoparticles/chemistry ; *Biofilms/drug effects/growth &amp; development ; *Silver/chemistry/pharmacology ; Animals ; Humans ; *Catfishes ; Mucus/metabolism ; Antineoplastic Agents/pharmacology/chemistry ; Vero Cells ; Fish Proteins/pharmacology/chemistry/metabolism ; Chlorocebus aethiops ; Cell Line, Tumor ; Microbial Sensitivity Tests ; Pseudomonas aeruginosa/drug effects ; Anti-Infective Agents/pharmacology/chemistry ; Staphylococcus aureus/drug effects/physiology ; Candida albicans/drug effects ; Epidermis/metabolism ; }, abstract = {Scientists know very little about the mechanisms underlying fish skin mucus, despite the fact that it is a component of the immune system. Fish skin mucus is an important component of defence against invasive infections. Recently, Fish skin and its mucus are gaining interest among immunologists. Characterization was done on the obtained silver nanoparticles Ag combined with Clarias gariepinus catfish epidermal mucus proteins (EMP-Ag-NPs) through UV-vis, FTIR, XRD, TEM, and SEM. Ag-NPs ranged in size from 4 to 20 nm, spherical in form and the angles were 38.10°, 44.20°, 64.40°, and 77.20°, Where wavelength change after formation of EMP-Ag-NPs as indicate of dark brown, the broad band recorded at wavelength at 391 nm. Additionally, the antimicrobial, antibiofilm and anticancer activities of EMP-Ag-NPs was assessed. The present results demonstrate high activity against unicellular fungi C. albicans, followed by E. faecalis. Antibiofilm results showed strong activity against both S. aureus and P. aeruginosa pathogens in a dose-dependent manner, without affecting planktonic cell growth. Also, cytotoxicity effect was investigated against normal cells (Vero), breast cancer cells (Mcf7) and hepatic carcinoma (HepG2) cell lines at concentrations (200-6.25 µg/mL) and current results showed highly anticancer effect of Ag-NPs at concentrations 100, 5 and 25 µg/mL exhibited rounding, shrinkage, deformation and granulation of Mcf7 and HepG2 with IC50 19.34 and 31.16 µg/mL respectively while Vero cells appeared rounded at concentration 50 µg/mL and normal shape at concentration 25, 12.5 and 6.25 µg/ml with IC50 35.85 µg/mL. This study evidence the potential efficacy of biologically generated Ag-NPs as a substitute medicinal agent against harmful microorganisms. Furthermore, it highlights their inhibitory effect on cancer cell lines.}, }
@article {pmid38702575, year = {2024}, author = {Pandey, P and Vavilala, SL}, title = {From Gene Editing to Biofilm Busting: CRISPR-CAS9 Against Antibiotic Resistance-A Review.}, journal = {Cell biochemistry and biophysics}, volume = {82}, number = {2}, pages = {549-560}, pmid = {38702575}, issn = {1559-0283}, mesh = {*CRISPR-Cas Systems ; *Biofilms/drug effects ; *Gene Editing ; Anti-Bacterial Agents/pharmacology ; Drug Resistance, Microbial/genetics ; Humans ; Bacteria/genetics/drug effects ; Drug Resistance, Bacterial/genetics ; }, abstract = {In recent decades, the development of novel antimicrobials has significantly slowed due to the emergence of antimicrobial resistance (AMR), intensifying the global struggle against infectious diseases. Microbial populations worldwide rapidly develop resistance due to the widespread use of antibiotics, primarily targeting drug-resistant germs. A prominent manifestation of this resistance is the formation of biofilms, where bacteria create protective layers using signaling pathways such as quorum sensing. In response to this challenge, the CRISPR-Cas9 method has emerged as a ground-breaking strategy to counter biofilms. Initially identified as the "adaptive immune system" of bacteria, CRISPR-Cas9 has evolved into a state-of-the-art genetic engineering tool. Its exceptional precision in altering specific genes across diverse microorganisms positions it as a promising alternative for addressing antibiotic resistance by selectively modifying genes in diverse microorganisms. This comprehensive review concentrates on the historical background, discovery, developmental stages, and distinct components of CRISPR Cas9 technology. Emphasizing its role as a widely used genome engineering tool, the review explores how CRISPR Cas9 can significantly contribute to the targeted disruption of genes responsible for biofilm formation, highlighting its pivotal role in reshaping strategies to combat antibiotic resistance and mitigate the challenges posed by biofilm-associated infectious diseases.}, }
@article {pmid38701663, year = {2024}, author = {Zibar Belasic, T and Badnjevic, M and Zigante, M and Mohar Vitezic, B and Spalj, S and Markova-Car, EP}, title = {Supragingival dental biofilm profile and biofilm control during orthodontic treatment with fixed orthodontic appliance: A randomized controlled trial.}, journal = {Archives of oral biology}, volume = {164}, number = {}, pages = {105984}, doi = {10.1016/j.archoralbio.2024.105984}, pmid = {38701663}, issn = {1879-1506}, mesh = {Humans ; *Biofilms/drug effects ; Female ; Adolescent ; *Chlorhexidine/analogs &amp; derivatives/pharmacology ; Child ; Male ; *Orthodontic Appliances, Fixed ; Young Adult ; *Fluorides/pharmacology ; Dental Plaque Index ; Oral Hygiene/methods ; Dental Plaque/microbiology ; Hydrogen-Ion Concentration ; Streptococcus mutans/drug effects ; Gingivitis/microbiology ; Anti-Infective Agents, Local/pharmacology ; Polymerase Chain Reaction ; Dental Caries/microbiology ; }, abstract = {OBJECTIVE: The effectiveness of supragingival dental biofilm control during orthodontic treatment and changes in the bacterial profile were analyzed.<br><br>DESIGN: Sixty-four participants aged 12-22 years (57% female) were included in the study. Participants underwent orthodontic treatment with fixed appliances and were randomly assigned to one of the three groups, which during a period of one month: (I) used chlorhexidine digluconate (CHX), (II) used high concentration of fluoride (F) gel and (III) performed standard oral hygiene. The plaque and gingivitis index, pH of biofilm and white spot lesions (WSL) were assessed. Changes of the bacteria in the biofilm were analyzed by the quantitative polymerase chain reaction RESULTS: Increase in the plaque index, pH of biofilm, and WSL was observed during orthodontic treatment with standard oral hygiene. Large interindividual variability was present, and the effects of one-month use of fluorides and CHX on clinical parameters were not significant. Despite standard hygiene the abundance of studied biofilm bacteria increased - the most Streptoccocus mutans (14.2x) and S. salivarius (3.3x), moderate Veillonella parvula (3x) and the least S. sobrinus (2.3x) and Agregatibacter actinomycetemcomitans (1.9x). The use of CHX reduced S. sobrinus (2.2x) and A. actinomycetemcomitans (1.9x). Fluoride use reduced A. actinomycetemcomitans (1.3x) and S. sobrinus (1.2x). Fluorides better controlled S. mutans than CHX.<br><br>CONCLUSION: Bacterial biomass in supragingival biofilm increased during treatment with metal orthodontic appliances, with greater increase in cariogenic bacteria than periopathogens. Fluoride controlled S. mutans, while CHX S. sobrinus and A. actinomycetemcomitans.}, }
@article {pmid38700735, year = {2024}, author = {Polat, T and Soyhan, &#x130; and Cebeci, S and İldeniz, TA&#xd6; and Gök, &#xd6; and Elmas, MA and Mozioğlu, E and Ünübol, N}, title = {New-generation biofilm effective antimicrobial peptides and a real-time anti-biofilm activity assay: CoMIC.}, journal = {Applied microbiology and biotechnology}, volume = {108}, number = {1}, pages = {316}, pmid = {38700735}, issn = {1432-0614}, mesh = {*Biofilms/drug effects ; *Antimicrobial Peptides/pharmacology/chemistry ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology/chemistry ; Models, Molecular ; Microscopy, Electron, Scanning ; Bacteria/drug effects ; }, abstract = {Nowadays, it is very important to produce new-generation drugs with antimicrobial properties that will target biofilm-induced infections. The first target for combating these microorganisms, which are the source itself. Antimicrobial peptides, which are more effective than antibiotics due to their ability to kill microorganisms and use a different metabolic pathway, are among the new options today. The aim of this study is to develop new-generation antibiotics that inhibit both biofilm-producing bacteria and the biofilm itself. For this purpose, we designed four different peptides by combining two amino acid forms (D- and L-) with the same sequence having alpha helix structures. It was found that the combined use of these two forms can increase antimicrobial efficacy more than 30-fold. These results are supported by molecular modeling and scanning electron microscopy (SEM), at the same time cytotoxicity (IC50) and hemotoxicity (HC50) values remained within the safe range. Furthermore, antibiofilm activities of these peptides were investigated. Since the existing biofilm inhibition methods in the literature do not technically simulate the exact situation, in this study, we have developed a real-time observable biofilm model and a new detection method based on it, which we call the CoMIC method. Findings have shown that the NET1 peptide with D-leucine amino acid in its structure and the NET3 peptide with D-arginine amino acid in its structure are effective in inhibiting biofilm. As a conclusion, our peptides can be considered as potential next-generation broad-spectrum antibiotic molecule/drug candidates that might be used in biofilm and clinical important bacteria. KEY POINTS: • Antimicrobial peptides were developed to inhibit both biofilms producing bacteria and the biofilm itself. • CoMIC will fill a very crucial gap in understanding biofilms and conducting the necessary quantitative studies. • Molecular modelling studies, NET1 peptide molecules tends to move towards and adhere to the membrane within nanoseconds.}, }
@article {pmid38700325, year = {2024}, author = {Liu, X and Lertsethtakarn, P and Mariscal, VT and Yildiz, F and Ottemann, KM}, title = {Counterclockwise rotation of the flagellum promotes biofilm initiation in Helicobacter pylori.}, journal = {mBio}, volume = {15}, number = {6}, pages = {e0044024}, pmid = {38700325}, issn = {2150-7511}, support = {R01 AI116946/AI/NIAID NIH HHS/United States ; R01 AI164682/AI/NIAID NIH HHS/United States ; AI164682//HHS | National Institutes of Health (NIH)/ ; 201904910692//China Scholarship Council (CSC)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Helicobacter pylori/physiology/genetics ; *Chemotaxis ; *Flagella/physiology/genetics ; *Bacterial Proteins/genetics/metabolism ; Signal Transduction ; Mutation ; Rotation ; }, abstract = {UNLABELLED: Motility promotes biofilm initiation during the early steps of this process: microbial surface association and attachment. Motility is controlled in part by chemotaxis signaling, so it seems reasonable that chemotaxis may also affect biofilm formation. There is a gap, however, in our understanding of the interactions between chemotaxis and biofilm formation, partly because most studies analyzed the phenotype of only a single chemotaxis signaling mutant, e.g., cheA. Here, we addressed the role of chemotaxis in biofilm formation using a full set of chemotaxis signaling mutants in Helicobacter pylori, a class I carcinogen that infects more than half the world's population and forms biofilms. Using mutants that lack each chemotaxis signaling protein, we found that chemotaxis signaling affected the biofilm initiation stage, but not mature biofilm formation. Surprisingly, some chemotaxis mutants elevated biofilm initiation, while others inhibited it in a manner that was not tied to chemotaxis ability or ligand input. Instead, the biofilm phenotype correlated with flagellar rotational bias. Specifically, mutants with a counterclockwise bias promoted biofilm initiation, e.g., ∆cheA, ∆cheW, or ∆cheV1; in contrast, those with a clockwise bias inhibited it, e.g., ∆cheZ, ∆chePep, or ∆cheV3. We tested this correlation using a counterclockwise bias-locked flagellum, which induced biofilm formation independent of the chemotaxis system. These CCW flagella, however, were not sufficient to induce biofilm formation, suggesting there are downstream players. Overall, our work highlights the new finding that flagellar rotational direction promotes biofilm initiation, with the chemotaxis signaling system operating as one mechanism to control flagellar rotation.<br><br>IMPORTANCE: Chemotaxis signaling systems have been reported to contribute to biofilm formation in many bacteria; however, how they regulate biofilm formation remains largely unknown. Chemotaxis systems are composed of many distinct kinds of proteins, but most previous work analyzed the biofilm effect of loss of only a few. Here, we explored chemotaxis' role during biofilm formation in the human-associated pathogenic bacterium Helicobacter pylori. We found that chemotaxis proteins are involved in biofilm initiation in a manner that correlated with how they affected flagellar rotation. Biofilm initiation was high in mutants with counterclockwise (CCW) flagellar bias and low in those with clockwise bias. We supported the idea that a major driver of biofilm formation is flagellar rotational direction using a CCW-locked flagellar mutant, which stays CCW independent of chemotaxis input and showed elevated biofilm initiation. Our data suggest that CCW-rotating flagella, independent of chemotaxis inputs, are a biofilm-promoting signal.}, }
@article {pmid38698252, year = {2024}, author = {Berto, LA and Ettmayer, JB and Stutzer, D and Nietzsche, S and Niederhauser, T and Burger, J and Sculean, A and Eick, S and Hofmann, M}, title = {In-vitro effects of novel periodontal scalers with a planar ultrasonic piezoelectric transducer on periodontal biofilm removal, dentine surface roughness, and periodontal ligament fibroblasts adhesion.}, journal = {Clinical oral investigations}, volume = {28}, number = {5}, pages = {294}, pmid = {38698252}, issn = {1436-3771}, mesh = {*Biofilms ; *Fibroblasts ; Humans ; *Surface Properties ; *Titanium ; *Dental Scaling/instrumentation ; In Vitro Techniques ; *Dentin/microbiology ; *Periodontal Ligament/cytology ; Transducers ; Cell Adhesion ; Stainless Steel ; Equipment Design ; Ultrasonic Therapy/instrumentation ; }, abstract = {OBJECTIVES: To compare ultrasonic scaler prototypes based on a planar piezoelectric transducer with different working frequencies featuring a titanium (Ti-20, Ti-28, and Ti-40) or stainless steel (SS-28) instrument, with a commercially available scaler (com-29) in terms of biofilm removal and reformation, dentine surface roughness and adhesion of periodontal fibroblasts.<br><br>MATERIALS AND METHODS: A periodontal multi-species biofilm was formed on specimens with dentine slices. Thereafter specimens were instrumented with scalers in a periodontal pocket model or left untreated (control). The remaining biofilms were quantified and allowed to reform on instrumented dentine slices. In addition, fibroblasts were seeded for attachment evaluation after 72&#xa0;h of incubation. Dentine surface roughness was analyzed before and after instrumentation.<br><br>RESULTS: All tested instruments reduced the colony-forming unit (cfu) counts by about 3 to 4 log10 and the biofilm quantity (each p&#x2009;<&#x2009;0.01 vs. control), but with no statistically significant difference between the instrumented groups. After 24-hour biofilm reformation, no differences in cfu counts were observed between any groups, but the biofilm quantity was about 50% in all instrumented groups compared to the control. The attachment of fibroblasts on instrumented dentine was significantly higher than on untreated dentine (p&#x2009;<&#x2009;0.05), with the exception of Ti-20. The dentine surface roughness was not affected by any instrumentation.<br><br>CONCLUSIONS: The planar piezoelectric scaler prototypes are able to efficiently remove biofilm without dentine surface alterations, regardless of the operating frequency or instrument material.<br><br>CLINICAL RELEVANCE: Ultrasonic scalers based on a planar piezoelectric transducer might be an alternative to currently available ultrasonic scalers.}, }
@article {pmid38695568, year = {2024}, author = {Kaplan, JB and Horswill, AR}, title = {Micrococcal nuclease regulates biofilm formation and dispersal in methicillin-resistant Staphylococcus aureus USA300.}, journal = {mSphere}, volume = {9}, number = {5}, pages = {e0012624}, pmid = {38695568}, issn = {2379-5042}, support = {P01 AI083211/AI/NIAID NIH HHS/United States ; AI083211//HHS | NIH | National Institute of Allergy and Infectious Diseases (NIAID)/ ; }, mesh = {*Biofilms/growth &amp; development/drug effects ; *Methicillin-Resistant Staphylococcus aureus/genetics/drug effects/physiology ; *Micrococcal Nuclease/genetics/metabolism ; Anti-Bacterial Agents/pharmacology ; Bacterial Proteins/genetics/metabolism ; DNA, Bacterial/genetics ; Virulence Factors/genetics ; Microbial Sensitivity Tests ; Amoxicillin/pharmacology ; }, abstract = {Biofilm formation is an important virulence factor for methicillin-resistant Staphylococcus aureus (MRSA). The extracellular matrix of MRSA biofilms contains significant amounts of double-stranded DNA that hold the biofilm together. MRSA cells secrete micrococcal nuclease (Nuc1), which degrades double-stranded DNA. In this study, we used standard methodologies to investigate the role of Nuc1 in MRSA biofilm formation and dispersal. We quantified biofilm formation and extracellular DNA (eDNA) levels in broth and agar cultures. In some experiments, cultures were supplemented with sub-MIC amoxicillin to induce biofilm formation. Biofilm erosion was quantitated by culturing biofilms on rods and enumerating detached colony-forming units (CFUs), and biofilm sloughing was investigated by perfusing biofilms cultured in glass tubes with fresh broth and measuring the sizes of the detached cell aggregates. We found that an MRSA nuc1[-] mutant strain produced significantly more biofilm and more eDNA than a wild-type strain, both in the absence and presence of sub-MIC amoxicillin. nuc1[-] mutant biofilms grown on rods detached significantly less than wild-type biofilms. Detachment was restored by exogenous DNase or complementing the nuc1[-] mutant. In the sloughing assay, nuc1[-] mutant biofilms released cell aggregates that were significantly larger than those released by wild-type biofilms. Our results suggest that Nuc1 modulates biofilm formation, biofilm detachment, and the sizes of detached cell aggregates. These processes may play a role in the spread and subsequent survival of MRSA biofilms during biofilm-related infections.IMPORTANCEInfections caused by antibiotic-resistant bacteria known as methicillin-resistant Staphylococcus aureus (MRSA) are a significant problem in hospitals. MRSA forms adherent biofilms on implanted medical devices such as catheters and breathing tubes. Bacteria can detach from biofilms on these devices and spread to other parts of the body such as the blood or lungs, where they can cause life-threatening infections. In this article, researchers show that MRSA secretes an enzyme known as thermonuclease that causes bacteria to detach from the biofilm. This is important because understanding the mechanism by which MRSA detaches from biofilms could lead to the development of procedures to mitigate the problem.}, }
@article {pmid38695444, year = {2024}, author = {Dos Santos, ACM and Mendes, FSF and Pompeo, FT and Watanabe, E and Macedo, AP and de Souza, VOP and Paranhos, HFO and Silva-Lovato, CH}, title = {Effectiveness of experimental dentifrices based on essential oils on biofilm on complete dentures: an in vitro study.}, journal = {Journal of applied oral science : revista FOB}, volume = {32}, number = {}, pages = {e20230397}, doi = {10.1590/1678-7757-2023-0397}, pmid = {38695444}, issn = {1678-7765}, mesh = {*Biofilms/drug effects ; *Dentifrices/pharmacology/chemistry ; *Oils, Volatile/pharmacology/chemistry ; *Denture, Complete/microbiology ; *Materials Testing ; Time Factors ; Reproducibility of Results ; Toothbrushing ; Colony Count, Microbial ; Staphylococcus aureus/drug effects ; Statistics, Nonparametric ; Streptococcus mutans/drug effects ; Analysis of Variance ; Microbial Viability/drug effects ; Candida albicans/drug effects ; Reference Values ; Acrylic Resins/chemistry/pharmacology ; }, abstract = {UNLABELLED: Specific products containing natural resources can contribute to the innovation of complete denture hygiene.<br><br>OBJECTIVE: To conduct an in vitro evaluation of experimental dentifrices containing essential oils of Bowdichia virgilioides Kunth (BvK), Copaifera officinalis (Co), Eucalyptus citriodora (Ec), Melaleuca alternifolia (Ma) and Pinus strobus (Ps) at 1%.<br><br>METHODOLOGY: The variables evaluated were organoleptic and physicochemical characteristics, abrasiveness (mechanical brushing machine) simulating 2.5 years, and microbial load (Colony Forming Units - CFU/mL), metabolic activity (XTT assay) and cell viability (Live/Dead&#xae; BacLight&#x2122; kit) of the multispecies biofilm (Streptococcus mutans: Sm, Staphylococcus aureus: Sa, Candida albicans: Ca and Candida glabrata: Cg). Specimens of heat-polymerized acrylic resins (n=256) (n=96 specimens for abrasiveness, n=72 for microbial load count, n=72 for biofilm metabolic activity, n=16 for cell viability and total biofilm quantification) with formed biofilm were divided into eight groups for manual brushing (20 seconds) with a dental brush and distilled water (NC: negative control), Trihydral (PC: positive control), placebo (Pl), BvK, Co, Ec, Ma or Ps. After brushing, the specimens were washed with PBS and immersed in Letheen Broth medium, and the suspension was sown in solid specific medium. The organoleptic characteristics were presented by descriptive analysis. The values of density, pH, consistency and viscosity were presented in a table. The data were analyzed with the Wald test in a generalized linear model, followed by the Kruskal-Wallis test, Dunn's test (mass change) and the Bonferroni test (UFC and XTT). The Wald test in Generalized Estimating Equations and the Bonferroni test were used to analyze cell viability.<br><br>RESULTS: All dentifrices showed stable organoleptic characteristics and adequate physicochemical properties. CN, Ec, Ps, Pl and PC showed low abrasiveness. There was a significant difference between the groups (p<0.001) for microbial load, metabolic activity and biofilm viability.<br><br>CONCLUSIONS: It was concluded that the BvK, Ec and Ps dentifrices are useful for cleaning complete dentures, as they have antimicrobial activity against biofilm. The dentifrices containing Bowdichia virgilioides Kunth showed medium abrasiveness and should be used with caution.}, }
@article {pmid38695072, year = {2024}, author = {Søborg, DA and Højris, B and Brinkmann, K and Pedersen, MR and Skovhus, TL}, title = {Characterizing the development of biofilm in polyethylene pipes in the non-chlorinated Danish drinking-water distribution system.}, journal = {Biofouling}, volume = {40}, number = {3-4}, pages = {262-279}, doi = {10.1080/08927014.2024.2343839}, pmid = {38695072}, issn = {1029-2454}, mesh = {*Biofilms/growth &amp; development ; *Polyethylene ; *Drinking Water/microbiology ; *Water Supply ; Water Microbiology ; Denmark ; Bacteria/classification/genetics/isolation &amp; purification ; Water Quality ; RNA, Ribosomal, 16S/genetics ; }, abstract = {In newly commissioned drinking-water polyethylene (PE) pipes, biofilm develops on the inner pipe surface. The microbial community composition from colonization to the establishment of mature biofilms is less known, including the effect on the distributed water quality. Biofilm development was followed through 1.5 years in PE-pipe side streams at two locations of a full-scale, non-chlorinated drinking-water distribution system (leaving a waterworks versus 5-6 km from a waterworks) along with inlet and outlet water quality. Mature biofilms were established after ∼8-9 months, dominated by Proteobacteria, Actinobacteria and Saccharibacteria (61-93% relative abundance), with a higher diversity (OTUs/Shannon Index/16S rRNA gene amplicon sequencing) in pipes in the far end of the distribution system. Comamonadaceae, and specifically Aquabacterium (>30% of reads), dominated young (∼1.5-month-old) biofilms. Young biofilms were linked to increased microbiological counts in drinking water (HPC/ATP/qPCR), while the establishment of mature biofilms led to a drop in HPC and benefited the water quality, highlighting the importance of optimizing commissioning procedures for rapidly achieving mature and stable biofilms.}, }
@article {pmid38694801, year = {2024}, author = {Zhou, X and Liu, H and Fan, X and Xu, X and Gao, Y and Bi, X and Cheng, L and Huang, S and Zhao, F and Yang, T}, title = {Innovative inbuilt moving bed biofilm reactor for nitrogen removal applied in household aquarium.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1373119}, pmid = {38694801}, issn = {1664-302X}, abstract = {An innovative inbuilt moving bed biofilm reactor (MBBR) was created to protect fish from nitrogen in a household aquarium. During the 90 experimental days, the ammonia nitrogen (NH4[+]-N) concentration in the aquarium with the inbuilt MBBR was always below 0.5 mg/L, which would not threaten the fish. Concurrently, nitrite and nitrate nitrogen concentrations were always below 0.05 mg/L and 4.5 mg/L, respectively. However, the blank contrast aquarium accumulated 1.985 mg/L NH4[+]-N on the 16th day, which caused the fish to die. The suspended biofilms could achieve the specific NH4[+]-N removal rate of 45.43 g/m[3]/d. Biofilms presented sparsely with filamentous structures and showed certain degrees of roughness. The bacterial communities of the suspended biofilms and the sediment were statistically different (p < 0.05), reflected in denitrifying and nitrifying bacteria. In particular, the relative abundance of Nitrospira reached 1.4%, while the genus was barely found in sediments. The suspended biofilms showed potentials for nitrification function with the predicted sequence numbers of ammonia monooxygenase [1.14.99.39] and hydroxylamine dehydrogenase [EC:1.7.2.6] of 220 and 221, while the values of the sediment were only 5 and 1. This study created an efficient NH4[+]-N removal inbuilt MBBR for household aquariums and explored its mechanism to afford a basis for its utilization.}, }
@article {pmid38693842, year = {2024}, author = {Meng, Y and Chen, S and Wang, C and Ni, X}, title = {Advances in Composite Biofilm Biomimetic Nanodrug Delivery Systems for Cancer Treatment.}, journal = {Technology in cancer research &amp; treatment}, volume = {23}, number = {}, pages = {15330338241250244}, pmid = {38693842}, issn = {1533-0338}, mesh = {Humans ; *Neoplasms/drug therapy ; *Biofilms/drug effects ; *Drug Delivery Systems ; *Biomimetics/methods ; *Antineoplastic Agents/administration &amp; dosage/pharmacology ; Biomimetic Materials/chemistry ; Animals ; Drug Carriers/chemistry ; }, abstract = {Single biofilm biomimetic nanodrug delivery systems based on single cell membranes, such as erythrocytes and cancer cells, have immune evasion ability, good biocompatibility, prolonged blood circulation, and high tumor targeting. Because of the different characteristics and functions of each single cell membrane, more researchers are using various hybrid cell membranes according to their specific needs. This review focuses on several different types of biomimetic nanodrug-delivery systems based on composite biofilms and looks forward to the challenges and possible development directions of biomimetic nanodrug-delivery systems based on composite biofilms to provide reference and ideas for future research.}, }
@article {pmid38692363, year = {2024}, author = {Zhang, X and Zhao, Y and Wang, Y and Qian, H and Xing, J and Joseph, A and Rene, ER and Li, J and Zhu, N}, title = {The interplay of hematite and photic biofilm triggers the acceleration of biotic nitrate removal.}, journal = {Chemosphere}, volume = {358}, number = {}, pages = {142136}, doi = {10.1016/j.chemosphere.2024.142136}, pmid = {38692363}, issn = {1879-1298}, mesh = {*Biofilms ; *Ferric Compounds/metabolism/chemistry ; *Nitrates/metabolism ; Oxidative Stress ; Pseudomonas/physiology/metabolism ; }, abstract = {The soil-water interface is replete with photic biofilm and iron minerals; however, the potential of how iron minerals promote biotic nitrate removal is still unknown. This study investigates the physiological and ecological responses of photic biofilm to hematite (Fe2O3), in order to explore a practically feasible approach for in-situ nitrate removal. The nitrate removal by photic biofilm was significantly higher in the presence of Fe2O3 (92.5%) compared to the control (82.8%). Results show that the presence of Fe2O3 changed the microbial community composition of the photic biofilm, facilitates the thriving of Magnetospirillum and Pseudomonas, and promotes the growth of photic biofilm represented by the extracellular polymeric substance (EPS) and the content of chlorophyll. The presence of Fe2O3 also induces oxidative stress (•O2[-]) in the photic biofilm, which was demonstrated by electron spin resonance spectrometry. However, the photic biofilm could improve the EPS productivity to prevent the entrance of Fe2O3 to cells in the biofilm matrix and mitigate oxidative stress. The Fe2O3 then promoted the relative abundance of Magnetospirillum and Pseudomonas and the activity of nitrate reductase, which accelerates nitrate reduction by the photic biofilm. This study provides an insight into the interaction between iron minerals and photic biofilm and demonstrates the possibility of combining biotic and abiotic methods to improve the in-situ nitrate removal rate.}, }
@article {pmid38690364, year = {2024}, author = {Meliefste, HM and Mudde, SE and Ammerman, NC and de Steenwinkel, JEM and Bax, HI}, title = {A laboratory perspective on Mycobacterium abscessus biofilm culture, characterization and drug activity testing.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1392606}, pmid = {38690364}, issn = {1664-302X}, abstract = {Mycobacterium abscessus is an emerging opportunistic pathogen causing severe pulmonary infections in patients with underlying lung disease and cystic fibrosis in particular. The rising prevalence of M. abscessus infections poses an alarming threat, as the success rates of available treatment options are limited. Central to this challenge is the absence of preclinical in vitro models that accurately mimic in vivo conditions and that can reliably predict treatment outcomes in patients. M. abscessus is notorious for its association with biofilm formation within the lung. Bacteria in biofilms are more recalcitrant to antibiotic treatment compared to planktonic bacteria, which likely contributes to the lack of correlation between preclinical drug activity testing (typically performed on planktonic bacteria) and treatment outcome. In recent years, there has been a growing interest in M. abscessus biofilm research. However, the absence of standardized methods for biofilm culture, biofilm characterization and drug activity testing has led to a wide spectrum of, sometimes inconsistent, findings across various studies. Factors such as strain selection, culture medium, and incubation time hugely impact biofilm development, phenotypical characteristics and antibiotic susceptibility. Additionally, a broad range of techniques are used to study M. abscessus biofilms, including quantification of colony-forming units, crystal violet staining and fluorescence microscopy. Yet, limitations of these techniques and the selected readouts for analysis affect study outcomes. Currently, research on the activity of conventional antibiotics, such as clarithromycin and amikacin, against M. abscessus biofilms yield ambiguous results, underscoring the substantial impact of experimental conditions on drug activity assessment. Beyond traditional drug activity testing, the exploration of novel anti-biofilm compounds and the improvement of in vitro biofilm models are ongoing. In this review, we outline the laboratory models, experimental variables and techniques that are used to study M. abscessus biofilms. We elaborate on the current insights of M. abscessus biofilm characteristics and describe the present understanding of the activity of traditional antibiotics, as well as potential novel compounds, against M. abscessus biofilms. Ultimately, this work contributes to the advancement of fundamental knowledge and practical applications of accurate preclinical M. abscessus models, thereby facilitating progress towards improved therapies for M. abscessus infections.}, }
@article {pmid38688866, year = {2024}, author = {Antoine, C and Laforêt, F and Fall, A and Blasdel, B and Delcenserie, V and Thiry, D}, title = {K1 capsule-dependent phage-driven evolution in Escherichia coli leading to phage resistance and biofilm production.}, journal = {Journal of applied microbiology}, volume = {135}, number = {5}, pages = {}, doi = {10.1093/jambio/lxae109}, pmid = {38688866}, issn = {1365-2672}, mesh = {Animals ; *Bacterial Capsules/genetics ; Bacteriophages/genetics/physiology ; *Biofilms/growth &amp; development ; Coliphages/genetics/physiology ; *Escherichia coli/virology/genetics ; Escherichia coli Infections/microbiology ; Larva/microbiology/virology ; Virulence/genetics ; Humans ; Moths/microbiology ; }, abstract = {AIMS: Understanding bacterial phage resistance mechanisms has implications for developing phage-based therapies. This study aimed to explore the development of phage resistance in Escherichia coli K1 isolates' to K1-ULINTec4, a K1-dependent bacteriophage.<br><br>METHODS AND RESULTS: Resistant colonies were isolated from two different strains (APEC 45 and C5), both previously exposed to K1-ULINTec4. Genome analysis and several parameters were assessed, including growth capacity, phage adsorption, phenotypic impact at capsular level, biofilm production, and virulence in the in vivo Galleria mellonella larvae model. One out of the six resistant isolates exhibited a significantly slower growth rate, suggesting the presence of a resistance mechanism altering its fitness. Comparative genomic analysis revealed insertion sequences in the region 2 of the kps gene cluster involved in the capsule biosynthesis. In addition, an immunoassay targeting the K1 capsule showed a very low positive reaction compared to the control. Nevertheless, microscopic images of resistant strains revealed the presence of capsules with a clustered organization of bacterial cells and biofilm assessment showed an increased biofilm production compared to the sensitive strains. In the G. mellonella model, larvae infected with phage-resistant isolates showed better survival rates than larvae infected with phage-sensitive strains.<br><br>CONCLUSIONS: A phage resistance mechanism was identified at the genomic level and had a negative impact on the K1 capsule production. The resistant isolates showed an increased biofilm production and a decreased virulence in vivo.}, }
@article {pmid38687259, year = {2024}, author = {Wang, C and Ma, Q and Zhang, J and Meng, N and Xu, D}, title = {Co-culture of benzalkonium chloride promotes the biofilm formation and decreases the antibiotic susceptibility of a Pseudomonas aeruginosa strain.}, journal = {Environmental science. Processes &amp; impacts}, volume = {26}, number = {5}, pages = {858-869}, doi = {10.1039/d4em00035h}, pmid = {38687259}, issn = {2050-7895}, mesh = {*Pseudomonas aeruginosa/drug effects/physiology/genetics ; *Biofilms/drug effects ; *Benzalkonium Compounds/pharmacology ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; }, abstract = {Benzalkonium chloride (BAC) is a disinfectant with broad-spectrum antibacterial properties, yet despite its widespread use and detection in the environment, the effects of BAC exposure on microorganisms remain poorly documented. Herein, the impacts of BAC on a Pseudomonas aeruginosa strain Jade-X were systematically investigated. The results demonstrated that the minimum inhibitory concentration (MIC) of BAC against strain Jade-X was 64 mg L[-1]. Exposure to BAC concentrations of 8, 16, 32, and 64 mg L[-1] significantly augmented biofilm formation by 2.03-, 2.43-, 2.96-, and 2.56-fold respectively. The swimming and twitching abilities, along with the virulence factor production, were inhibited. Consistently, quantitative reverse transcription PCR assays revealed significant downregulation of genes related to flagellate- and pili-mediated motilities (flgD, flgE, pilB, pilQ, and motB), as well as phzA and phzB genes involved in pyocyanin production. The results of disk diffusion and MIC assays demonstrated that BAC decreased the antibiotic susceptibility of ciprofloxacin, levofloxacin, norfloxacin, and tetracycline. Conversely, an opposite trend was observed for polymyxin B and ceftriaxone. Genomic analysis revealed that strain Jade-X harbored eleven resistance-nodulation-cell division efflux pumps, with mexCD-oprJ exhibiting significant upregulation while mexEF-oprN and mexGHI-opmD were downregulated. In addition, the quorum sensing-related regulators LasR and RhlR were also suppressed, implying that BAC might modulate the physiological and biochemical behaviors of strain Jade-X by attenuating the quorum sensing system. This study enhances our understanding of interactions between BAC and P. aeruginosa, providing valuable insights to guide the regulation and rational use of BAC.}, }
@article {pmid38686667, year = {2024}, author = {Rafiee, Z and Rezaie, M and Choi, S}, title = {Combined electrical-electrochemical phenotypic profiling of antibiotic susceptibility of in vitro biofilm models.}, journal = {The Analyst}, volume = {149}, number = {11}, pages = {3224-3235}, doi = {10.1039/d4an00393d}, pmid = {38686667}, issn = {1364-5528}, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; Pseudomonas aeruginosa/drug effects/physiology ; Escherichia coli/drug effects/physiology ; Staphylococcus aureus/drug effects/physiology ; Phenotype ; Electrochemical Techniques/methods ; }, abstract = {More than 65% of bacterial infections are caused by biofilms. However, standard biofilm susceptibility tests are not available for clinical use. All conventional biofilm models suffer from a long formation time and fail to mimic in vivo microbial biofilm conditions. Moreover, biofilms make it difficult to monitor the effectiveness of antibiotics. This work creates a powerful yet simple method to form a target biofilm and develops an innovative approach to monitoring the antibiotic's efficacy against a biofilm-associated infection. A paper-based culture platform can provide a new strategy for rapid microbial biofilm formation through capillary action. A combined electrical-electrochemical technique monitors bacterial metabolism rapidly and reliably by measuring microbial extracellular electron transfer (EET) and using electrochemical impedance spectroscopy (EIS) across a microbe-electrode interface. Three representative pathogens, Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus, form their biofilms controllably within an hour. Within another hour their susceptibilities to three frontline antibiotics with different action modes (gentamicin, ciprofloxacin, and ceftazidime) are examined. Our antibiotic susceptibility testing (AST) technique provides a quantifiable minimum inhibitory concentration (MIC) of those antibiotics against the in vitro biofilm models and characterizes their action mechanisms. The results will have an important positive effect because they provide immediately actionable healthcare information at a reduced cost, revolutionizing public healthcare.}, }
@article {pmid38686557, year = {2024}, author = {Yang, L and Wang, X and Ma, Z and Sui, Y and Liu, X}, title = {Fangchinoline inhibits growth and biofilm of Candida albicans by inducing ROS overproduction.}, journal = {Journal of cellular and molecular medicine}, volume = {28}, number = {9}, pages = {e18354}, pmid = {38686557}, issn = {1582-4934}, support = {20220505041ZP//the Science and Technology Development Plan Project of Jilin Province/ ; 20200201595JC//Natural Science Foundation of Jilin Province/ ; JJKH20231220KJ//the Education Department of Jilin Province/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Candida albicans/drug effects/growth &amp; development ; *Antifungal Agents/pharmacology ; *Reactive Oxygen Species/metabolism ; *Benzylisoquinolines/pharmacology ; *Microbial Sensitivity Tests ; Hyphae/drug effects/growth &amp; development ; }, abstract = {Infections caused by Candida species, especially Candida albicans, threaten the public health and create economic burden. Shortage of antifungals and emergence of drug resistance call for new antifungal therapies while natural products were attractive sources for developing new drugs. In our study, fangchinoline, a bis-benzylisoquinoline alkaloid from Chinese herb Stephania tetrandra S. Moore, exerted antifungal effects on planktonic growth of several Candida species including C. albicans, with MIC no more than 50 μg/mL. In addition, results from microscopic, MTT and XTT reduction assays showed that fangchinoline had inhibitory activities against the multiple virulence factors of C. albicans, such as adhesion, hyphal growth and biofilm formation. Furthermore, this compound could also suppress the metabolic activity of preformed C. albicans biofilms. PI staining, followed by confocal laser scanning microscope (CLSM) analysis showed that fangchinoline can elevate permeability of cell membrane. DCFH-DA staining suggested its anti-Candida mechanism also involved overproduction of intracellular ROS, which was further confirmed by N-acetyl-cysteine rescue tests. Moreover, fangchinoline showed synergy with three antifungal drugs (amphotericin B, fluconazole and caspofungin), further indicating its potential use in treating C. albicans infections. Therefore, these results indicated that fangchinoline could be a potential candidate for developing anti-Candida therapies.}, }
@article {pmid38685359, year = {2024}, author = {Farah, N and Lim, CW and Chin, VK and Chong, PP and Basir, R and Yeo, WWY and Tay, ST and Choo, S and Lee, TY}, title = {Photoactivated riboflavin inhibits planktonic and biofilm growth of Candida albicans and non-albicans Candida species.}, journal = {Microbial pathogenesis}, volume = {191}, number = {}, pages = {106665}, doi = {10.1016/j.micpath.2024.106665}, pmid = {38685359}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development/radiation effects ; *Riboflavin/pharmacology ; *Microbial Sensitivity Tests ; *Antifungal Agents/pharmacology ; *Candida/drug effects/growth &amp; development ; *Ultraviolet Rays ; *Candida albicans/drug effects ; Plankton/drug effects ; Fluconazole/pharmacology ; Humans ; }, abstract = {Fungal infections caused by Candida species pose a serious threat to humankind. Antibiotics abuse and the ability of Candida species to form biofilm have escalated the emergence of drug resistance in clinical settings and hence, rendered it more difficult to treat Candida-related diseases. Lethal effects of Candida infection are often due to inefficacy of antimicrobial treatments and failure of host immune response to clear infections. Previous studies have shown that a combination of riboflavin with UVA (riboflavin/UVA) light demonstrate candidacidal activity albeit its mechanism of actions remain elusive. Thus, this study sought to investigate antifungal and antibiofilm properties by combining riboflavin with UVA against Candida albicans and non-albicans Candida species. The MIC20 for the fluconazole and riboflavin/UVA against the Candida species tested was within the range of 0.125-2 μg/mL while the SMIC50 was 32 μg/mL. Present findings indicate that the inhibitory activities exerted by riboflavin/UVA towards planktonic cells are slightly less effective as compared to controls. However, the efficacy of the combination towards Candida species biofilms showed otherwise. Inhibitory effects exerted by riboflavin/UVA towards most of the tested Candida species biofilms points towards a variation in mode of action that could make it an ideal alternative therapeutic for biofilm-related infections.}, }
@article {pmid38683213, year = {2024}, author = {Lendel, AM and Antonova, NP and Grigoriev, IV and Usachev, EV and Gushchin, VA and Vasina, DV}, title = {Biofilm-disrupting effects of phage endolysins LysAm24, LysAp22, LysECD7, and LysSi3: breakdown the matrix.}, journal = {World journal of microbiology &amp; biotechnology}, volume = {40}, number = {6}, pages = {186}, pmid = {38683213}, issn = {1573-0972}, support = {23-74-10027//Russian Science Foundation/ ; 23-74-10027//Russian Science Foundation/ ; 23-74-10027//Russian Science Foundation/ ; 23-74-10027//Russian Science Foundation/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Endopeptidases/metabolism/pharmacology/chemistry ; *Bacteriophages/enzymology ; Acinetobacter baumannii/drug effects ; Klebsiella pneumoniae/drug effects ; Viral Proteins/metabolism ; Anti-Bacterial Agents/pharmacology/chemistry ; N-Acetylmuramoyl-L-alanine Amidase/metabolism/chemistry ; }, abstract = {The ability of most opportunistic bacteria to form biofilms, coupled with antimicrobial resistance, hinder the efforts to control widespread infections, resulting in high risks of negative outcomes and economic costs. Endolysins are promising compounds that efficiently combat bacteria, including multidrug-resistant strains and biofilms, without a low probability of subsequent emergence of stable endolysin-resistant phenotypes. However, the details of antibiofilm effects of these enzymes are poorly understood. To elucidate the interactions of bacteriophage endolysins LysAm24, LysAp22, LysECD7, and LysSi3 with bacterial films formed by Gram-negative species, we estimated their composition and assessed the endolysins' effects on the most abundant exopolymers in vitro. The obtained data suggests a pronounced efficiency of these lysins against biofilms with high (Klebsiella pneumoniae) and low (Acinetobacter baumannii) matrix contents, or dual-species biofilms, resulting in at least a twofold loss of the biomass. These peptidoglycan hydrolases interacted diversely with protective compounds of biofilms such as extracellular DNA and polyanionic carbohydrates, indicating a spectrum of biofilm-disrupting effects for bacteriolytic phage enzymes. Specifically, we detected disruption of acid exopolysaccharides by LysAp22, strong DNA-binding capacity of LysAm24, both of these interactions for LysECD7, and neither of them for LysSi3.}, }
@article {pmid38683167, year = {2024}, author = {Sun, G and Huang, S and Wang, S and Li, Y}, title = {Nanomaterial-based drug-delivery system as an aid to antimicrobial photodynamic therapy in treating oral biofilm.}, journal = {Future microbiology}, volume = {19}, number = {8}, pages = {741-759}, pmid = {38683167}, issn = {1746-0921}, mesh = {*Biofilms/drug effects ; *Photochemotherapy/methods ; Humans ; *Nanostructures/chemistry ; *Photosensitizing Agents/pharmacology/chemistry/administration &amp; dosage ; *Drug Delivery Systems ; Mouth/microbiology ; Anti-Bacterial Agents/pharmacology/chemistry/administration &amp; dosage ; Anti-Infective Agents/pharmacology/administration &amp; dosage/chemistry ; Animals ; Drug Carriers/chemistry ; Bacteria/drug effects ; }, abstract = {Diverse microorganisms live as biofilm in the mouth accounts for oral diseases and treatment failure. For decades, the prevention and treatment of oral biofilm is a global challenge. Antimicrobial photodynamic therapy (aPDT) holds promise for oral biofilm elimination due to its several traits, including broad-spectrum antimicrobial capacity, lower possibility of resistance and low cytotoxicity. However, the physicochemical properties of photosensitizers and the biological barrier of oral biofilm have limited the efficiency of aPDT. Nanomaterials has been used to fabricate nanocarriers to improve photosensitizer properties and thus enhance antimicrobial effect. In this review, we have discussed the challenges of aPDT used in dentistry, categorized the nanomaterial-delivery system and listed the possible mechanisms involved in nanomaterials when enhancing aPDT effect.}, }
@article {pmid38683166, year = {2024}, author = {Rajangam, SL and Narasimhan, MK}, title = {Current treatment strategies for targeting virulence factors and biofilm formation in Acinetobacter baumannii.}, journal = {Future microbiology}, volume = {19}, number = {10}, pages = {941-961}, pmid = {38683166}, issn = {1746-0921}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Acinetobacter baumannii/drug effects/physiology/pathogenicity/genetics ; Humans ; *Acinetobacter Infections/microbiology/drug therapy ; *Virulence Factors/genetics/metabolism ; *Anti-Bacterial Agents/pharmacology ; Cross Infection/microbiology/drug therapy ; COVID-19 ; SARS-CoV-2/drug effects/physiology ; }, abstract = {A higher prevalence of Acinetobacter baumannii infections and mortality rate has been reported recently in hospital-acquired infections (HAI). The biofilm-forming capability of A. baumannii makes it an extremely dangerous pathogen, especially in device-associated hospital-acquired infections (DA-HAI), thereby it resists the penetration of antibiotics. Further, the transmission of the SARS-CoV-2 virus was exacerbated in DA-HAI during the epidemic. This review specifically examines the complex interconnections between several components and genes that play a role in the biofilm formation and the development of infections. The current review provides insights into innovative treatments and therapeutic approaches to combat A. baumannii biofilm-related infections, thereby ultimately improving patient outcomes and reducing the burden of HAI.}, }
@article {pmid38683039, year = {2024}, author = {Oh, MJ and Kim, JH and Kim, J and Lee, S and Xiang, Z and Liu, Y and Koo, H and Lee, D}, title = {Drug-loaded adhesive microparticles for biofilm prevention on oral surfaces.}, journal = {Journal of materials chemistry. B}, volume = {12}, number = {20}, pages = {4935-4944}, pmid = {38683039}, issn = {2050-7518}, support = {R01 DE025220/DE/NIDCR NIH HHS/United States ; }, mesh = {*Biofilms/drug effects ; *Candida albicans/drug effects/physiology ; *Antifungal Agents/pharmacology/chemistry ; *Surface Properties ; Polylactic Acid-Polyglycolic Acid Copolymer/chemistry ; Humans ; Mouth/microbiology ; Adhesives/chemistry/pharmacology ; Particle Size ; Polyethylene Glycols/chemistry ; Drug Carriers/chemistry ; }, abstract = {The oral cavity, a warm and moist environment, is prone to the proliferation of microorganisms like Candida albicans (C. albicans), which forms robust biofilms on biotic and abiotic surfaces, leading to challenging infections. These biofilms are resistant to conventional treatments due to their resilience against antimicrobials and immune responses. The dynamic nature of the oral cavity, including the salivary flow and varying surface properties, complicates the delivery of therapeutic agents. To address these challenges, we introduce dendritic microparticles engineered for enhanced adhesion to dental surfaces and effective delivery of antifungal agents and antibiofilm enzymes. These microparticles are fabricated using a water-in-oil-in-water emulsion process involving a blend of poly(lactic-co-glycolic acid) (PLGA) random copolymer (RCP) and PLGA-b-poly(ethylene glycol) (PLGA-b-PEG) block copolymer (BCP), resulting in particles with surface dendrites that exhibit strong adhesion to oral surfaces. Our study demonstrates the potential of these adhesive microparticles for oral applications. The adhesion tests on various oral surfaces, including dental resin, hydroxyapatite, tooth enamel, and mucosal tissues, reveal superior adhesion of these microparticles compared to conventional spherical ones. Furthermore, the release kinetics of nystatin from these microparticles show a sustained release pattern that can kill C. albicans. The biodegradation of these microparticles on tooth surfaces and their efficacy in preventing fungal biofilms have also been demonstrated. Our findings highlight the effectiveness of adhesive microparticles in delivering therapeutic agents within the oral cavity, offering a promising approach to combat biofilm-associated infections.}, }
@article {pmid38682908, year = {2024}, author = {Michaelis, S and Chen, T and Schmid, C and Hilbi, H}, title = {Nitric oxide signaling through three receptors regulates virulence, biofilm formation, and phenotypic heterogeneity of Legionella pneumophila.}, journal = {mBio}, volume = {15}, number = {6}, pages = {e0071024}, pmid = {38682908}, issn = {2150-7511}, support = {31003A_175557, 310030_200706//Schweizerischer Nationalfonds zur F&#xf6;rderung der Wissenschaftlichen Forschung (SNF)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Legionella pneumophila/genetics/pathogenicity/physiology/metabolism ; *Nitric Oxide/metabolism ; *Signal Transduction ; Virulence ; *Gene Expression Regulation, Bacterial ; *Bacterial Proteins/genetics/metabolism ; Phenotype ; Macrophages/microbiology ; Quorum Sensing ; }, abstract = {UNLABELLED: The causative agent of Legionnaires' disease, Legionella pneumophila, is an environmental bacterium, that replicates in macrophages, parasitizes amoeba, and forms biofilms. L. pneumophila employs the Legionella quorum sensing (Lqs) system and the transcription factor LvbR to control various bacterial traits, including virulence and biofilm architecture. LvbR negatively regulates the nitric oxide (NO) receptor Hnox1, linking quorum sensing to NO signaling. Here, we assessed the response of L. pneumophila to NO and investigated bacterial receptors underlying this process. Chemical NO donors, such as dipropylenetriamine (DPTA) NONOate and sodium nitroprusside (SNP), delayed and reduced the expression of the promoters for flagellin (PflaA) and the 6S small regulatory RNA (P6SRNA). Marker-less L. pneumophila mutant strains lacking individual (Hnox1, Hnox2, or NosP) or all three NO receptors (triple knockout, TKO) grew like the parental strain in media. However, in the TKO strain, the reduction of PflaA expression by DPTA NONOate was less pronounced, suggesting that the NO receptors are implicated in NO signaling. In the ΔnosP mutant, the lvbR promoter was upregulated, indicating that NosP negatively regulates LvbR. The single and triple NO receptor mutant strains were impaired for growth in phagocytes, and phenotypic heterogeneity of non-growing/growing bacteria in amoebae was regulated by the NO receptors. The single NO receptor and TKO mutant strains showed altered biofilm architecture and lack of response of biofilms to NO. In summary, we provide evidence that L. pneumophila regulates virulence, intracellular phenotypic heterogeneity, and biofilm formation through NO and three functionally non-redundant NO receptors, Hnox1, Hnox2, and NosP.<br><br>IMPORTANCE: The highly reactive diatomic gas molecule nitric oxide (NO) is produced by eukaryotes and bacteria to promote short-range and transient signaling within and between neighboring cells. Despite its importance as an inter-kingdom and intra-bacterial signaling molecule, the bacterial response and the underlying components of the signaling pathways are poorly characterized. The environmental bacterium Legionella pneumophila forms biofilms and replicates in protozoan and mammalian phagocytes. L. pneumophila harbors three putative NO receptors, one of which crosstalks with the Legionella quorum sensing (Lqs)-LvbR network to regulate various bacterial traits, including virulence and biofilm architecture. In this study, we used pharmacological, genetic, and cell biological approaches to assess the response of L. pneumophila to NO and to demonstrate that the putative NO receptors are implicated in NO detection, bacterial replication in phagocytes, intracellular phenotypic heterogeneity, and biofilm formation.}, }
@article {pmid38681738, year = {2024}, author = {Orfali, R and Ghaffar, S and AlAjlan, L and Perveen, S and Al-Turki, E and Ameen, F}, title = {Diabetes-related lower limb wounds: Antibiotic susceptibility pattern and biofilm formation.}, journal = {Saudi pharmaceutical journal : SPJ : the official publication of the Saudi Pharmaceutical Society}, volume = {32}, number = {6}, pages = {102069}, pmid = {38681738}, issn = {1319-0164}, abstract = {The expeditious incidence of diabetes mellitus in Riyadh, Saudi Arabia, there is a significant increase in the total number of people with diabetic foot ulcers. For diabetic lower limb wound infections (DLWs) to be effectively treated, information on the prevalence of bacteria that cause in this region as well as their patterns of antibiotic resistance is significant. Growing evidence indicates that biofilm formers are present in chronic DFU and that these biofilm formers promote the emergence of multi-drug antibiotic resistant (MDR) strains and therapeutic rejection. The current study targeted to isolate bacteria from wounds caused by diabetes specifically at hospitals in Riyadh and assess the bacterium's resistance to antibiotics and propensity to develop biofilms. Totally 63 pathogenic microbes were identified from 70 patients suffering from DFU. Sixteen (25.4%) of the 63 bacterial strains were gram-positive, and 47 (74.6%) were gram-negative. Most of the gram-negative bacteria were resistant to tigecycline, nitrofurantoin, ampicillin, amoxicillin, cefalotin, and cefoxitin. Several gram-negative bacteria are susceptible to piperacillin, meropenem, amikacin, gentamicin, imipenem, ciprofloxacin, and trimethoprim. The most significant antibiotic that demonstrated 100% susceptibility to all pathogens was meropenem. Serratia marcescens and Staphylococcus aureus were shown to have significant biofilm formers. MDR bacterial strains comprised about 87.5% of the biofilm former strains. To the best of our knowledge, Riyadh, Saudi Arabia is the first region where Serratia marcescens was the most common bacteria from DFU infections. Our research findings would deliver information on evidence-based alternative strategies to develop effective treatment approaches for DFU treatment.}, }
@article {pmid38681224, year = {2024}, author = {Lai, CH and Wong, MY and Huang, TY and Kao, CC and Lin, YH and Lu, CH and Huang, YK}, title = {Exploration of agr types, virulence-associated genes, and biofilm formation ability in Staphylococcus aureus isolates from hemodialysis patients with vascular access infections.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1367016}, pmid = {38681224}, issn = {2235-2988}, mesh = {Female ; Humans ; Male ; Middle Aged ; *Bacterial Proteins/genetics/metabolism ; *Biofilms/growth &amp; development ; Catheter-Related Infections/microbiology ; Methicillin-Resistant Staphylococcus aureus/genetics/pathogenicity ; *Renal Dialysis/adverse effects ; *Staphylococcal Infections/microbiology ; *Staphylococcus aureus/genetics/pathogenicity ; *Trans-Activators/genetics ; *Virulence Factors/genetics ; }, abstract = {INTRODUCTION: Staphylococcus aureus, is a pathogen commonly encountered in both community and hospital settings. Patients receiving hemodialysis treatment face an elevated risk of vascular access infections (VAIs) particularly Staphylococcus aureus, infection. This heightened risk is attributed to the characteristics of Staphylococcus aureus, , enabling it to adhere to suitable surfaces and form biofilms, thereby rendering it resistant to external interventions and complicating treatment efforts.<br><br>METHODS: Therefore this study utilized PCR and microtiter dish biofilm formation assay to determine the difference in the virulence genes and biofilm formation among in our study collected of 103 Staphylococcus aureus, isolates from hemodialysis patients utilizing arteriovenous grafts (AVGs), tunneled cuffed catheters (TCCs), and arteriovenous fistulas (AVFs) during November 2013 to December 2021.<br><br>RESULTS: Our findings revealed that both MRSA and MSSA isolates exhibited strong biofilm production capabilities. Additionally, we confirmed the presence of agr types and virulence genes through PCR analysis. The majority of the collected isolates were identified as agr type I. However, agr type II isolates displayed a higher average number of virulence genes, with MRSA isolates exhibiting a variety of virulence genes. Notably, combinations of biofilm-associated genes, such as eno-clfA-clfB-fib-icaA-icaD and eno-clfA-clfB-fib-fnbB-icaA-icaD, were prevalent among Staphylococcus aureus, isolates obtained from vascular access infections.<br><br>DISCUSSION: These insights contribute to a better understanding of the molecular characteristics associated with Staphylococcus aureus, infections in hemodialysis patients and provided more targeted and effective treatment approaches.}, }
@article {pmid38680918, year = {2024}, author = {Behzadnia, A and Moosavi-Nasab, M and Oliyaei, N}, title = {Anti-biofilm activity of marine algae-derived bioactive compounds.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1270174}, pmid = {38680918}, issn = {1664-302X}, abstract = {A large number of microbial species tend to communicate and produce biofilm which causes numerous microbial infections, antibiotic resistance, and economic problems across different industries. Therefore, advanced anti-biofilms are required with novel attributes and targets, such as quorum sensing communication system. Meanwhile, quorum sensing inhibitors as promising anti-biofilm molecules result in the inhibition of particular phenotype expression blocking of cell-to-cell communication, which would be more acceptable than conventional strategies. Many natural products are identified as anti-biofilm agents from different plants, microorganisms, and marine extracts. Marine algae are promising sources of broadly novel compounds with anti-biofilm activity. Algae extracts and their metabolites such as sulfated polysaccharides (fucoidan), carotenoids (zeaxanthin and lutein), lipid and fatty acids (γ-linolenic acid and linoleic acid), and phlorotannins can inhibit the cell attachment, reduce the cell growth, interfere in quorum sensing pathway by blocking related enzymes, and disrupt extracellular polymeric substances. In this review, the mechanisms of biofilm formation, quorum sensing pathway, and recently identified marine algae natural products as anti-biofilm agents will be discussed.}, }
@article {pmid38680142, year = {2024}, author = {Lenchenko, E and Sachivkina, N and Petrukhina, O and Petukhov, N and Zharov, A and Zhabo, N and Avdonina, M}, title = {Anatomical, pathological, and histological features of experimental respiratory infection of birds by biofilm-forming bacteria Staphylococcus aureus.}, journal = {Veterinary world}, volume = {17}, number = {3}, pages = {612-619}, pmid = {38680142}, issn = {0972-8988}, abstract = {BACKGROUND AND AIM: The pathogenesis of staphylococcal infections is mediated by virulence factors, such as enzymes, toxins, and biofilms, which increase the resistance of microorganisms to host immune system evasion. Testing and searching for standardized multi-level algorithms for the indication and differentiation of biofilms at the early stages of diagnosis will contribute to the development of preventive measures to control the critical points of technology and manage dangerous risk factors for the spread of infectious diseases. This research aimed to study the main stages of Staphylococcus aureus biofilm formation in in vitro experiments and to analyze the dynamics of respiratory syndrome development in chickens infected with these bacteria.<br><br>MATERIALS AND METHODS: Experimental reproduction of the infectious process was performed using laboratory models: 10-day-old White Leghorn chickens (n = 20). Before the experiments, the birds were divided into two groups according to the principle of analogs: Group I (control, n = 10): the birds were intranasally inoculated with 0.5 cm[3] of 0.9% NaCl solution; Group II (experiment, n = 10): the birds were intranasally inoculated with a suspension of S. aureus bacteria, 0.5 cm[3], concentration 1 billion/cm[3].<br><br>RESULTS: Colonization of individual areas of the substrate under study in vitro occurred gradually from the sedimentation and adhesion of single motile planktonic cells to the attachment stage of microcolony development. Staining preparations with gentian violet due to the "metachromosia" property of this dye are a quick and fairly simple way to differentiate cells and the intercellular matrix of biofilms. Fixation with vapors of glutaraldehyde and osmium tetroxide preserves the natural architecture of biofilms under optical and scanning electron microscopy. Pure cultures of S. aureus microorganisms were isolated from the blood, lungs, small intestine, liver, kidneys, and spleen after 5-10 days during experimental infection of chickens. Clinical signs of respiratory syndrome developed within 5-6 days after infection. Acute and subacute serous-fibrinous airsacculitis, characterized by edema and thickening of the membranes of the air sacs and the presence of turbid, watery, foamy contents in the cavity, was the most characteristic pathomorphological sign. The signs of acute congestive hyperemia and one-sided serous-fibrinous pneumonia developed with significant thickening of fibrinous deposits. In Garder's gland, there was an increase in the number of secretory sections, indicating hypersecretion of the glands. In the lymphoid follicles of Meckel's diverticulum, leukocytes, usually lymphocytes, and pseudoeosinophils were detected.<br><br>CONCLUSIONS: Hydration and heteromorphism of the internal environment of biofilms determine the localization of differentiated cells in a three-dimensional matrix for protection against adverse factors. The most characteristic pathomorphological sign was the development of acute and subacute serous-fibrinous airsacculitis when reproducing the infectious process in susceptible models. There was a significant thickening of fibrinous deposits and signs of acute congestive hyperemia and one or two serous-fibrinous pneumonia developed.}, }
@article {pmid38680028, year = {2025}, author = {Sobel, JD}, title = {Biofilm in Bacterial Vaginosis: A Legitimate Therapeutic Challenge?.}, journal = {The Journal of infectious diseases}, volume = {231}, number = {1}, pages = {40-43}, doi = {10.1093/infdis/jiae135}, pmid = {38680028}, issn = {1537-6613}, }
@article {pmid38679227, year = {2024}, author = {Pereira, IL and Cardoso, TL and Wozeak, DR and Caballero, PS and Buchhorn de Freitas, S and Pinto Seixas Neto, AC and da Silva Pinto, L and Hartwig, DD}, title = {Antibodies anti-rFilF protein has anti-biofilm activity against carbapenem-resistant Acinetobacter baumannii.}, journal = {Microbes and infection}, volume = {26}, number = {5-6}, pages = {105347}, doi = {10.1016/j.micinf.2024.105347}, pmid = {38679227}, issn = {1769-714X}, mesh = {*Biofilms/drug effects ; *Acinetobacter baumannii/immunology/drug effects ; Animals ; *Antibodies, Bacterial/immunology ; *Carbapenems/pharmacology ; Mice ; Immunoglobulin G/immunology ; Anti-Bacterial Agents/pharmacology ; Acinetobacter Infections/immunology/microbiology ; Recombinant Proteins/immunology/pharmacology/genetics ; Mice, Inbred BALB C ; Female ; Escherichia coli/genetics/immunology ; Bacterial Outer Membrane Proteins/immunology/genetics ; }, abstract = {Acinetobacter baumannii is an opportunistic bacterium that causes infection in several sites. Carbapenem-resistant A. baumannii strains (CRAb) lead the World Health Organization's list of 12 pathogens considered a priority for developing new antimicrobials. The pathogenicity of A. baumannii is related to the different virulence factors employed in the colonization of biotic and abiotic surfaces, biofilm formation and multidrug resistance. We analyze the outer membrane protein FilF from A. baumannii in silico and produce it in recombinant form (rFilF). rFilF protein was successfully expressed in Escherichia coli BL21 Star in an insoluble form. Immunization with rFilF induced significant anti-rFilF IgG antibody production in mice, detected by indirect enzyme-linked immunosorbent assay, since the first evaluation until 49th. On the last experimentation day, the predominant immunoglobulin found was IgG1 followed by IgG2a, IgG2b, IgM, IgG3, and IgA. We observe that interleukins 4 and 10 show significant production after the 28th day of experimentation in mice immunized with rFilF. Anti-rFilF pAbs were able to inhibit biofilm formation in nine CRAb strains evaluated, and in the standard strain ATCC® 19606. These results demonstrate the anti-biofilm activity of anti-rFilF antibodies, promising in the development of a non-antibiotic approach based on the control of CRAb strains.}, }
@article {pmid38679172, year = {2024}, author = {Loi, JX and Syutsubo, K and Rabuni, MF and Takemura, Y and Aoki, M and Chua, ASM}, title = {Downflow sponge biofilm reactors for polluted raw water treatment: Performance optimisation, kinetics, and microbial community.}, journal = {Chemosphere}, volume = {358}, number = {}, pages = {142156}, doi = {10.1016/j.chemosphere.2024.142156}, pmid = {38679172}, issn = {1879-1298}, mesh = {*Biofilms ; *Bioreactors/microbiology ; *Nitrification ; Ammonium Compounds/metabolism ; Water Purification/methods ; Kinetics ; Water Pollutants, Chemical/metabolism/analysis ; Waste Disposal, Fluid/methods ; Microbiota ; Nitrites/metabolism ; Bacteria/metabolism/genetics ; RNA, Ribosomal, 16S/genetics ; Nitrates/metabolism ; }, abstract = {Water outages caused by elevated ammonium (NH4[+]-N) levels are a prevalent problem faced by conventional raw water treatment plants in developing countries. A treatment solution requires a short hydraulic retention time (HRT) to overcome nitrification rate limitation in oligotrophic conditions. In this study, the performance of polluted raw water treatment using a green downflow sponge biofilm (DSB) technology was evaluated. We operated two DSB reactors, DSB-1 and DSB-2 under different NH4[+]-N concentration ranges (DSB-1: 3.2-5.0 mg L[-1]; DSB-2: 1.7-2.6 mg L[-1]) over 360 days and monitored their performance under short HRT (60 min, 30 min, 20 min, and 15 min). The experimental results revealed vertical segregation of organic removal in the upper reactor depths and nitrification in the lower depths. Under the shortest HRT of 15 min, both DSB reactors achieved stable NH4[+]-N and chemical oxygen demand removal (≥95%) and produced minimal effluent nitrite (NO2[-]-N). DSB system could facilitate complete NH4[+]-N oxidation to nitrate (NO3[-]-N) without external aeration energy requirement. The 16S rRNA sequencing data revealed that nitrifying bacteria Nitrosomonas and Nitrospira in the reactor were stratified. Putative comammox bacteria with high ammonia affinity was successfully enriched in DSB-2 operating at a lower NH4[+]-N loading rate, which is advantageous in oligotrophic treatment. This study suggests that a high hydraulic rate DSB system with efficient ammonia removal could incorporate ammonia treatment capability into polluted raw water treatment process and ensure safe water supply in many developing countries.}, }
@article {pmid38678634, year = {2024}, author = {Omer, SA and Ganjo, AR and Haji, SH and Smail, SB}, title = {Accessory Gene Regulator (agr) group polymorphisms in methicillin-resistant Staphylococcus aureus and its association with biofilm formation.}, journal = {Cellular and molecular biology (Noisy-le-Grand, France)}, volume = {70}, number = {4}, pages = {1-7}, doi = {10.14715/cmb/2024.70.4.1}, pmid = {38678634}, issn = {1165-158X}, mesh = {Anti-Bacterial Agents/pharmacology ; *Bacterial Proteins/genetics/metabolism ; *Biofilms/growth &amp; development/drug effects ; Hydrogen Peroxide/pharmacology/metabolism ; Lipase/genetics/metabolism ; *Methicillin-Resistant Staphylococcus aureus/genetics/drug effects/isolation &amp; purification/physiology ; Microbial Sensitivity Tests ; Polymorphism, Genetic ; Staphylococcal Infections/microbiology ; Trans-Activators/genetics/metabolism ; *Xanthophylls ; Humans ; }, abstract = {Methicillin-resistant Staphylococcus aureus (MRSA) is one of the main causes of community- and hospital-acquired infections. The expression of virulence genes in S. aureus is arranged by regulators like the accessory gene regulator (agr). The present study aims to estimate phenotypic characteristics of S. aureus and investigate the occurrence of agr genes with their correlation to biofilm formation. In this study, 34 MRSA strains out of 100 S. aureus isolates were recovered in a variety of clinical samples. Phenotypic characterization and ability of biofilm formation were assessed. About 8(24%) of isolates were biofilm producers. The percentages of biofilm production among isolates were 3(37.5%), 2(25%), 3(37.5%) as strong, moderate, and weak, respectively. Furthermore, the resistance rates for all antibiotics were higher in biofilm producers and 76% of the isolates were staphyloxanthin producers, around 82% of the strains showed resistance to H2O2. Hemolytic activity was detected in 74% of the total isolates. The activity of the protease enzyme was 68%. The lipase enzyme was active in 79% of the tested S. aureus isolates. The majority of isolates were established to be agrI 84%, followed by agrII 53%, agrIII 32%, and 30% of the isolates have agr IV. Our study indicated that the majority of MRSA isolates were non-biofilm producers and the agr I is the most dominant type. Thus, agr I is not correlated with biofilm production.}, }
@article {pmid38678425, year = {2024}, author = {Suresh, K and Pillai, D}, title = {Prevalence of antimicrobial resistance, biofilm formation, efflux pump activity, and virulence capabilities in multi-drug-resistant Klebsiella pneumoniae isolated from freshwater fish farms.}, journal = {Journal of water and health}, volume = {22}, number = {4}, pages = {721-734}, pmid = {38678425}, issn = {1477-8920}, mesh = {*Klebsiella pneumoniae/drug effects/genetics/pathogenicity/isolation &amp; purification/physiology ; *Biofilms/drug effects ; Animals ; Virulence ; *Drug Resistance, Multiple, Bacterial ; *Fishes/microbiology ; *Anti-Bacterial Agents/pharmacology ; India/epidemiology ; Fresh Water/microbiology ; Aquaculture ; Microbial Sensitivity Tests ; Bacterial Proteins/genetics/metabolism ; }, abstract = {The present study aimed to determine the antibiotic resistance, underlying mechanisms, antibiotic residues, and virulence genes involved in 32 multi-drug-resistant Klebsiella pneumoniae isolates from freshwater fishes in Andhra Pradesh, India. Antibiogram studies revealed that all isolates were multi-drug-resistant, harbored tetA (96.8%), tetC (59.3%), tetD (71.9%), nfsA (59.3%), nfsB (53.1%), sul2 (68.7%), qnrC (43.7%), qnrD (50%), blaSHV (75%), blaTEM (68.7%), and blaCTX-M (93.7%) genes. Multiple antibiotic resistance index was calculated as 0.54. Sixteen isolates were confirmed to be hyper-virulent and harbored magA and rmpA genes. In total, 46.9, 31.2, and 21.9% of the isolates were categorized as strong, moderate, or weak biofilm formers, respectively. All isolates possessed an active efflux pump and harbored acrA, acrB, acrAB, and tolC genes in 94% of the isolates, followed by mdtK (56.2%). Porins such as ompK35 and ompK36 were detected in 59.3 and 62.5% of the isolates, respectively. Virulence genes fimH-1, mrkD, and entB were present in 84.3, 81.2, 87.5% of the isolates, respectively. These findings imply a potential threat that multi-drug-resistant bacterial pathogens could transmit to surrounding environments and humans through contaminated water and the aquaculture food chain.}, }
@article {pmid38678421, year = {2024}, author = {Oyewale, AT and Odetoyin, BW and Oluduro, AO and Adeniyi, IF}, title = {Occurrence of coliforms and biofilm-forming bacteria in raw, treated, and distributed water from two waterwork systems in Osun State, Southwestern Nigeria.}, journal = {Journal of water and health}, volume = {22}, number = {4}, pages = {673-688}, pmid = {38678421}, issn = {1477-8920}, mesh = {Nigeria ; *Biofilms ; *Enterobacteriaceae/isolation &amp; purification ; *Drinking Water/microbiology ; *Water Microbiology ; *Water Supply ; Bacteria/isolation &amp; purification/classification/genetics ; Water Purification/methods ; }, abstract = {This study assessed the bacteriological quality of raw, treated, and distributed water from Ede-Erinle and Opa reservoirs in Osun State, Nigeria. This was to determine the potability of water from these waterwork stations. Eighteen sampling points were established across the two reservoir networks for this study. Samples were collected bi-monthly for two annual cycles. Serial dilution and pour plate methods were employed for the enumeration of bacterial load. Total heterotrophic bacteria count (THBC) and total coliform bacteria count (TCBC) were enumerated on nutrient and MacConkey agar at 37 °C, respectively. Bacterial isolates were characterized using biochemical identification methods with reference to Bergey's Manual of Determinative Bacteriology. Bacterial isolates and biofilm formation were further identified molecularly through the PCR method using specific universal primers. Mean values of THBC and TCBC in distributed water from Ede-Erinle (9.61 × 10[4] ± 1.50 × 10[4] CFU/mL; 69.56 ± 26.81 CFU/mL) and Opa waterworks (9.58 × 10[4] ± 2.55 × 10[4] CFU/mL; 142.94 ± 44.41 CFU/mL) exceeded permissible limits for drinking water. Paenibacillus lautus, Bacillus pseudomycoides, Pseudomonas aeruginosa, and Pseudomonas stutzeri showed biofilm-forming capacity. The study concluded that the presence of coliforms and biofilm-forming bacteria in distributed water implies that the water is unfit for consumption without further treatment.}, }
@article {pmid38677238, year = {2024}, author = {Zhu, W and Liu, J and Zhang, Y and Zhao, D and Li, S and Dou, H and Wang, H and Xia, X}, title = {The role of rcpA gene in regulating biofilm formation and virulence in Vibrio parahaemolyticus.}, journal = {International journal of food microbiology}, volume = {418}, number = {}, pages = {110714}, doi = {10.1016/j.ijfoodmicro.2024.110714}, pmid = {38677238}, issn = {1879-3460}, mesh = {*Vibrio parahaemolyticus/genetics/pathogenicity ; *Biofilms/growth &amp; development ; Animals ; Virulence/genetics ; Mice ; *Bacterial Proteins/genetics/metabolism ; *Vibrio Infections/microbiology ; *Gene Expression Regulation, Bacterial ; Female ; }, abstract = {Vibrio parahaemolyticus (V. parahaemolyticus) is a common seafood-borne pathogen that can colonize the intestine of host and cause gastroenteritis. Biofilm formation by V. parahaemolyticus enhances its persistence in various environments, which poses a series of threats to food safety. This work aims to investigate the function of rcpA gene in biofilm formation and virulence of V. parahaemolyticus. Deletion of rcpA significantly reduced motility, biofilm biomass, and extracellular polymeric substances, and inhibited biofilm formation on a variety of food and food contact surfaces. In mice infection model, mice infected with ∆rcpA strain exhibited a decreased rate of pathogen colonization, a lower level of inflammatory cytokines, and less tissue damage when compared to mice infected with wild type strain. RNA-seq analysis revealed that 374 genes were differentially expressed in the rcpA deletion mutant, which include genes related to quorum sensing, flagellar system, ribosome, type VI secretion system, biotin metabolism and transcriptional regulation. In conclusion, rcpA plays a role in determining biofilm formation and virulence of V. parahaemolyticus and further research is necessitated to fully understand its function in V. parahaemolyticus.}, }
@article {pmid38677122, year = {2024}, author = {Xue, J and Ma, H and Dong, X and Shi, K and Zhou, X and Qiao, Y and Gao, Y and Liu, Y and Feng, Y and Jiang, Q}, title = {Insights into the response of electroactive biofilm with petroleum hydrocarbons degradation ability to quorum sensing signals.}, journal = {Journal of hazardous materials}, volume = {471}, number = {}, pages = {134407}, doi = {10.1016/j.jhazmat.2024.134407}, pmid = {38677122}, issn = {1873-3336}, mesh = {*Biofilms/drug effects ; *Quorum Sensing ; *Petroleum/metabolism ; *Hydrocarbons/metabolism ; *Biodegradation, Environmental ; Bacteria/metabolism/genetics ; Electrochemical Techniques ; Bioelectric Energy Sources ; }, abstract = {Bioelectrochemical technologies based on electroactive biofilms (EAB) are promising for petroleum hydrocarbons (PHs) remediation as anode can serve as inexhaustible electron acceptor. However, the toxicity of PHs might inhibit the formation and function of EABs. Quorum sensing (QS) is ideal for boosting the performance of EABs, but its potential effects on reshaping microbial composition of EABs in treating PHs are poorly understood. Herein, two AHL signals, C4-HSL and C12-HSL, were employed to promote EABs for PHs degradation. The start-times of AHL-mediated EABs decreased by 18-26%, and maximum current densities increased by 28-63%. Meanwhile, the removal of total PHs increased to over 90%. AHLs facilitate thicker and more compact biofilm as well as higher viability. AHLs enhanced the electroactivity and direct electron transfer capability. The total abundance of PH-degrading bacteria increased from 52.05% to 75.33% and 72.02%, and the proportion of electroactive bacteria increased from 26.14% to 62.72% and 63.30% for MFC-C4 and MFC-C12. Microbial networks became more complex, aggregated, and stable with addition of AHLs. Furthermore, AHL-stimulated EABs showed higher abundance of genes related to PHs degradation. This work advanced our understanding of AHL-mediated QS in maintaining the stable function of microbial communities in the biodegradation process of petroleum hydrocarbons.}, }
@article {pmid38677054, year = {2024}, author = {Gourari-Bouzouina, K and Boucherit-Otmani, Z and Seghir, A and Baba Ahmed-Kazi Tani, ZZ and Bendoukha, I and Benahmed, A and Aissaoui, M and Boucherit, K}, title = {Evaluation of mixed biofilm production by Candida spp. and Staphylococcus aureus strains co-isolated from cystic fibrosis patients in northwest Algeria.}, journal = {Diagnostic microbiology and infectious disease}, volume = {109}, number = {3}, pages = {116321}, doi = {10.1016/j.diagmicrobio.2024.116321}, pmid = {38677054}, issn = {1879-0070}, mesh = {*Biofilms/growth &amp; development ; Humans ; *Cystic Fibrosis/microbiology/complications ; *Staphylococcus aureus/isolation &amp; purification/physiology ; Algeria ; *Candida/isolation &amp; purification/classification/physiology ; *Sputum/microbiology ; Staphylococcal Infections/microbiology ; Coinfection/microbiology ; Female ; Male ; Adult ; Candidiasis/microbiology ; Microscopy, Electron, Scanning ; Young Adult ; Adolescent ; Child ; }, abstract = {Cystic fibrosis patients' lungs are chronically colonized by multiple microbial species capable of forming biofilms. This study aimed to characterize the polymicrobial biofilm formed by Candida spp. and S. aureus, co-isolated from sputum samples of cystic fibrosis patients regarding microbial density, metabolic activity, and structure. 67 samples from 28 patients were collected with a 96% alteration rate. 34% showed alterations by both Candida spp. and Gram-positive bacteria, predominantly Candida spp. and S. aureus in 77% of cases, accounting for 6 associations. Biofilm biomass was quantified using the crystal violet assay, and metabolic activity was assessed using the MTT reduction assay. Scanning electron microscopy analyzed the C. tropicalis/S. aureus24 biofilm architecture. Candida spp. isolates demonstrated the ability to form mixed biofilms with S. aureus. The C. tropicalis/S. aureus24 association exhibited the highest production of biofilm and metabolic activity, along with the C. albicans17/C. rugosa/S. aureus7 in both single and mixed biofilms.}, }
@article {pmid38677035, year = {2024}, author = {Han, X and Fu, L and Yu, J and Li, K and Deng, Z and Shu, R and Wang, D and You, J and Zeng, EY}, title = {Effects of erythromycin on biofilm formation and resistance mutation of Escherichia coli on pristine and UV-aged polystyrene microplastics.}, journal = {Water research}, volume = {256}, number = {}, pages = {121628}, doi = {10.1016/j.watres.2024.121628}, pmid = {38677035}, issn = {1879-2448}, mesh = {*Biofilms/drug effects ; *Escherichia coli/drug effects/genetics ; *Erythromycin/pharmacology ; *Polystyrenes ; *Mutation ; *Microplastics/toxicity ; Anti-Bacterial Agents/pharmacology ; Ultraviolet Rays ; Drug Resistance, Bacterial/genetics ; }, abstract = {Microplastics (MPs) and antibiotics co-occur widely in the environment and pose combined risk to microbial communities. The present study investigated the effects of erythromycin on biofilm formation and resistance mutation of a model bacterium, E. coli, on the surface of pristine and UV-aged polystyrene (PS) MPs sized 1-2 mm. The properties of UV-aged PS were significantly altered compared to pristine PS, with notable increases in specific surface area, carbonyl index, hydrophilicity, and hydroxyl radical content. Importantly, the adsorption capacity of UV-aged PS towards erythromycin was approximately 8-fold higher than that of pristine PS. Biofilms colonizing on UV-aged PS had a greater cell count (5.6 × 10[8] CFU mg[-1]) and a higher frequency of resistance mutation (1.0 × 10[-7]) than those on pristine PS (1.4 × 10[8] CFU mg[-1] and 1.4 × 10[-8], respectively). Moreover, erythromycin at 0.1 and 1.0 mg L[-1] significantly (p < 0.05) promoted the formation and resistance mutation of biofilm on both pristine and UV-aged PS. DNA sequencing results confirmed that the biofilm resistance was attributed to point mutations in rpoB segment of the bacterial genome. qPCR results demonstrated that both UV aging and erythromycin repressed the expression levels of a global regulator rpoS in biofilm bacteria, as well as two DNA mismatch repair genes mutS and uvrD, which was likely to contribute to increased resistance mutation frequency.}, }
@article {pmid38675162, year = {2024}, author = {Hałasa, R and Turecka, K and Mizerska, U and Krauze-Baranowska, M}, title = {Anti-Helicobacter pylori Biofilm Extracts from Rubus idaeus and Rubus occidentalis.}, journal = {Pharmaceutics}, volume = {16}, number = {4}, pages = {}, pmid = {38675162}, issn = {1999-4923}, abstract = {Helicobacter pylori infections are still an important health problem and are directly related to the development of gastric ulcer, gastric adenocarcinoma, mucosal lymphoid tissue lymphoma, and diabetes. At the same time, the number of substances/drugs effective against these bacteria is limited due to increasing resistance. Raw plant materials from various species of the Rubus genus-fruits and shoots-have shown antimicrobial activity in numerous studies against different bacteria, including H. pylori in a planktonic form. Research carried out on a model using fragments of intravenous infusions and triphenyl tetrazolium chloride (TTC) as a dye showed that the shoot extract of Rubus idaeus 'Willamette', the fruit extract of R. idaeus 'Poranna Rosa', R. idaeus and R. idaeus 'Laszka', and R. occidentalis Litacz' prevent the formation of biofilm by H. pylori. Active concentrations inhibiting biofilm formation were 6.65 mg/mL for shoots and 16.65 mg/mL for fruits. However, in the resulting biofilm, the extract from the shoots of R. idaeus 'Willamette' and the fruit of R. idaeus 'Poranna Rosa' at a concentration of 16.65 mg/mL was active against living bacteria, and the remaining extracts showed such activity at a concentration of 33.3 mg/mL. In studies on the interaction of the extract with antibiotics on biofilm, the extract from the shoots of R. idaeus 'Willamette' showed synergy with doxycycline and levofloxacin, additivity with amoxicillin and clarithromycin, and neutrality with metronidazole. H. pylori biofilm research was carried out in a newly elaborated research model-culture on fragments of intravenous infusions with the addition of TTC as a marker of living bacterial cells. The research results may constitute the basis for the development of new combination therapies for the treatment of H. pylori infections, including its resistant strains. The proposed new biofilm research model, which is cheap and effective, may allow testing of new substances that are potentially more effective against H. pylori and other biofilm-forming bacterial strains.}, }
@article {pmid38675139, year = {2024}, author = {Wultańska, D and Piotrowski, M and Pituch, H}, title = {Antimicrobial Effects of Some Natural Products on Adhesion and Biofilm Inhibition of Clostridioides difficile.}, journal = {Pharmaceutics}, volume = {16}, number = {4}, pages = {}, pmid = {38675139}, issn = {1999-4923}, support = {2019/03/X/NZ6/01445//National Science Center/ ; }, abstract = {Understanding the potential antimicrobial properties of natural compounds and their impacts on Clostridioides difficile virulence factors may aid in developing alternative strategies for preventing and treating C. difficile infections (CDI). In this study, we investigated the bactericidal effects of ginger oil (GO), peppermint oil (PO), curcumin (CU), cinnamon aldehyde (CI), and trans-cinnamaldehyde (TCI) on the adhesion and biofilm disruption of C. difficile. We used three reference and five clinical C. difficile strains of different ribotypes. The bactericidal activity was assessed using the broth microdilution method. The adhesion was evaluated using human epithelial cell lines, and biofilm formation was visualized by confocal laser scanning microscopy. All tested strains exhibited susceptibility to CU, with minimum inhibitory concentration (MIC) values ranging from 128 µg/mL to 2048 µg/mL. Similarly, all strains were susceptible to CI and TCI, with MIC values ranging from 6.25% (v/v) to 25% (v/v). Most of the tested substances reduced the adhesion of C. difficile strains, while two tested strains showed significantly higher adhesion when co-incubated with the tested substances. Similar observations were made for biofilm formation, with observed density and morphology varied depending on the strain. In conclusion, the tested products demonstrated bactericidal activity and reduced the adhesion of C. difficile strains. They may be considered for further studies as potential antimicrobial agents targeting biofilm-related infections.}, }
@article {pmid38674728, year = {2024}, author = {Di Domenico, EG and Oliva, A and Guembe, M}, title = {Biofilm-Related Infections in Healthcare: Moving towards New Horizons.}, journal = {Microorganisms}, volume = {12}, number = {4}, pages = {}, pmid = {38674728}, issn = {2076-2607}, abstract = {In this Special Issue, titled "Biofilm-Related Infections in Healthcare", we have reported considerable progress in understanding the physiology and pathology of biofilms [...].}, }
@article {pmid38674703, year = {2024}, author = {Kispert, S and Liguori, M and Velikaneye, C and Qiu, C and Wang, S and Zhang, N and Gu, H}, title = {Role of Staphylococcus aureus's Buoyant Density in the Development of Biofilm Associated Antibiotic Susceptibility.}, journal = {Microorganisms}, volume = {12}, number = {4}, pages = {}, pmid = {38674703}, issn = {2076-2607}, support = {80NSSC20M0129//Connecticut Space Grant College Consortium/ ; }, abstract = {Biofilms are clusters of microorganisms that form at various interfaces, including those between air and liquid or liquid and solid. Due to their roles in enhancing wastewater treatment processes, and their unfortunate propensity to cause persistent human infections through lowering antibiotic susceptibility, understanding and managing bacterial biofilms is of paramount importance. A pivotal stage in biofilm development is the initial bacterial attachment to these interfaces. However, the determinants of bacterial cell choice in colonizing an interface first and heterogeneity in bacterial adhesion remain elusive. Our research has unveiled variations in the buoyant density of free-swimming Staphylococcus aureus cells, irrespective of their growth phase. Cells with a low cell buoyant density, characterized by fewer cell contents, exhibited lower susceptibility to antibiotic treatments (100 μg/mL vancomycin) and favored biofilm formation at air-liquid interfaces. In contrast, cells with higher cell buoyant density, which have richer cell contents, were more vulnerable to antibiotics and predominantly formed biofilms on liquid-solid interfaces when contained upright. Cells with low cell buoyant density were not able to revert to a more antibiotic sensitive and high cell buoyant density phenotype. In essence, S. aureus cells with higher cell buoyant density may be more inclined to adhere to upright substrates.}, }
@article {pmid38674628, year = {2024}, author = {Bereanu, AS and Vintilă, BI and Bereanu, R and Codru, IR and Hașegan, A and Olteanu, C and Săceleanu, V and Sava, M}, title = {TiO2 Nanocomposite Coatings and Inactivation of Carbapenemase-Producing Klebsiella Pneumoniae Biofilm-Opportunities and Challenges.}, journal = {Microorganisms}, volume = {12}, number = {4}, pages = {}, pmid = {38674628}, issn = {2076-2607}, abstract = {The worldwide increase of multidrug-resistant Gram-negative bacteria is a global threat. The emergence and global spread of Klebsiella pneumoniae carbapenemase- (KPC-) producing Klebsiella pneumoniae represent a particular concern. This pathogen has increased resistance and abilities to persist in human reservoirs, in hospital environments, on medical devices, and to generate biofilms. Mortality related to this microorganism is high among immunosuppressed oncological patients and those with multiple hospitalizations and an extended stay in intensive care. There is a severe threat posed by the ability of biofilms to grow and resist antibiotics. Various nanotechnology-based strategies have been studied and developed to prevent and combat serious health problems caused by biofilm infections. The aim of this review was to evaluate the implications of nanotechnology in eradicating biofilms with KPC-producing Klebsiella pneumoniae, one of the bacteria most frequently associated with nosocomial infections in intensive care units, including in our department, and to highlight studies presenting the potential applicability of TiO2 nanocomposite materials in hospital practice. We also described the frequency of the presence of bacterial biofilms on medical surfaces, devices, and equipment. TiO2 nanocomposite coatings are one of the best long-term options for antimicrobial efficacy due to their biocompatibility, stability, corrosion resistance, and low cost; they find their applicability in hospital practice due to their critical antimicrobial role for surfaces and orthopedic and dental implants. The International Agency for Research on Cancer has recently classified titanium dioxide nanoparticles (TiO2 NPs) as possibly carcinogenic. Currently, there is an interest in the ecological, non-toxic synthesis of TiO2 nanoparticles via biological methods. Biogenic, non-toxic nanoparticles have remarkable properties due to their biocompatibility, stability, and size. Few studies have mentioned the use of nanoparticle-coated surfaces as antibiofilm agents. A literature review was performed to identify publications related to KPC-producing Klebsiella pneumoniae biofilms and antimicrobial TiO2 photocatalytic nanocomposite coatings. There are few reviews on the antibacterial and antibiofilm applications of TiO2 photocatalytic nanocomposite coatings. TiO2 nanoparticles demonstrated marked antibiofilm activity, but being nano in size, these nanoparticles can penetrate cell membranes and may initiate cellular toxicity and genotoxicity. Biogenic TiO2 nanoparticles obtained via green, ecological technology have less applicability but are actively investigated.}, }
@article {pmid38674584, year = {2024}, author = {Iaconis, A and De Plano, LM and Caccamo, A and Franco, D and Conoci, S}, title = {Anti-Biofilm Strategies: A Focused Review on Innovative Approaches.}, journal = {Microorganisms}, volume = {12}, number = {4}, pages = {}, pmid = {38674584}, issn = {2076-2607}, abstract = {Biofilm (BF) can give rise to systemic infections, prolonged hospitalization times, and, in the worst case, death. This review aims to provide an overview of recent strategies for the prevention and destruction of pathogenic BFs. First, the main phases of the life cycle of BF and maturation will be described to identify potential targets for anti-BF approaches. Then, an approach acting on bacterial adhesion, quorum sensing (QS), and the extracellular polymeric substance (EPS) matrix will be introduced and discussed. Finally, bacteriophage-mediated strategies will be presented as innovative approaches against BF inhibition/destruction.}, }
@article {pmid38674531, year = {2024}, author = {Mahavy, CE and Razanatseheno, AJ and Mol, A and Ngezahayo, J and Duez, P and El Jaziri, M and Baucher, M and Rasamiravaka, T}, title = {Edible Medicinal Guava Fruit (Psidium guajava L.) Are a Source of Anti-Biofilm Compounds against Pseudomonas aeruginosa.}, journal = {Plants (Basel, Switzerland)}, volume = {13}, number = {8}, pages = {}, pmid = {38674531}, issn = {2223-7747}, abstract = {Psidium guajava is one of the most common edible medicinal plants frequently used in Malagasy traditional medicine to treat gastrointestinal infections. In order to evaluate their probable antibacterial activities, three organic extracts (successive extractions by hexane, dichloromethane, and ethanol) of ripe guava fruits were assessed for their bactericidal and anti-virulence properties against P. aeruginosa PAO1. Although these three extracts have shown no direct antibacterial activity (MIC of 1000 µg/mL) and, at the non-bactericidal concentration of 100 µg/mL, no impact on the production of major P. aeruginosa PAO1 virulence factors (pyocyanin and rhamnolipids), the hexane and dichloromethane extracts showed significant anti-biofilm properties and the dichloromethane extract disrupted the P. aeruginosa PAO1 swarming motility. Bioguided fractionation of the dichloromethane extract led to the isolation and identification of lycopene and β-sitosterol-β-D-glucoside as major anti-biofilm compounds. Interestingly, both compounds disrupt P. aeruginosa PAO1 biofilm formation and maintenance with IC50 of 1383 µM and 131 µM, respectively. More interestingly, both compounds displayed a synergistic effect with tobramycin with a two-fold increase in its effectiveness in killing biofilm-encapsulated P. aeruginosa PAO1. The present study validates the traditional uses of this edible medicinal plant, indicating the therapeutic effectiveness of guava fruits plausibly through the presence of these tri- and tetraterpenoids, which deserve to be tested against pathogens generally implicated in diarrhea.}, }
@article {pmid38673451, year = {2024}, author = {Pardo, A and Fiorini, V and Zangani, A and Faccioni, P and Signoriello, A and Albanese, M and Lombardo, G}, title = {Topical Agents in Biofilm Disaggregation: A Systematic Review and Meta-Analysis.}, journal = {Journal of clinical medicine}, volume = {13}, number = {8}, pages = {}, pmid = {38673451}, issn = {2077-0383}, abstract = {Background: to evaluate the effectiveness of different topical agents in biofilm disaggregation during non-surgical periodontal therapy. Methods: the search strategy was conducted according to the PRISMA 2020 on Pubmed, Cochrane Library, Scopus, and Web of Science, and it was registered in PROSPERO, ID: CRD42023474232. It included studies comparing non-surgical periodontal therapy (NSPT) with and without the application of topical agents for biofilm disruption. A risk of bias analysis, a qualitative analysis, and a quantitative analysis were performed. Results: out of 1583 records, 11 articles were included: 10 randomized clinical trials and one retrospective analysis. The total number of participants considered in the 11 articles included in the study was 386. The primary outcomes were probing pocket depth (PPD), clinical attachment level (CAL), and bleeding indices. The secondary outcomes were plaque indices, gingival recessions, and microbiological parameters. The meta-analysis revealed the following: [Weighted mean difference (WMD): -0.37; 95% confidence interval (CI) (-0.62, -0.12), heterogeneity I[2]: 79%, statistical significance p = 0.004]. Conclusions: the meta-analysis of probing pocket depth reduction (PPD) between baseline and follow-up at 3-6 months showed a statistically significant result in favor of sulfonated phenolics gel. The scientific evidence is still limited and heterogeneous; further randomized clinical trials are required.}, }
@article {pmid38671777, year = {2024}, author = {Panio, A and Ionescu, AC and La Ferla, B and Zoia, L and Savadori, P and Tartaglia, GM and Brambilla, E}, title = {Cellulose Nanocrystals Show Anti-Adherent and Anti-Biofilm Properties against Oral Microorganisms.}, journal = {Bioengineering (Basel, Switzerland)}, volume = {11}, number = {4}, pages = {}, pmid = {38671777}, issn = {2306-5354}, abstract = {Cellulose nanocrystals (CNCs) are cellulose-derived nanomaterials that can be easily obtained, e.g., from vegetable waste produced by circular economies. They show promising antimicrobial activity and an absence of side effects and toxicity. This study investigated the ability of CNCs to reduce microbial adherence and biofilm formation using in vitro microbiological models reproducing the oral environment. Microbial adherence by microbial strains of oral interest, Streptococcus mutans and Candida albicans, was evaluated on the surfaces of salivary pellicle-coated enamel disks in the presence of different aqueous solutions of CNCs. The anti-biofilm activity of the same CNC solutions was tested against S. mutans and an oral microcosm model based on mixed plaque inoculum using a continuous-flow bioreactor. Results showed the excellent anti-adherent activity of the CNCs against the tested strains from the lowest concentration tested (0.032 wt. %, p < 0.001). Such activity was significantly higher against S. mutans than against C. albicans (p < 0.01), suggesting a selective anti-adherent activity against pathogenic strains. At the same time, there was a minimal, albeit significant, anti-biofilm activity (0.5 and 4 wt. % CNC solution for S. mutans and oral microcosm, respectively, p = 0.01). This makes CNCs particularly interesting as anticaries agents, encouraging their use in the oral field.}, }
@article {pmid38669236, year = {2024}, author = {Kuper, TJ and Islam, MM and Peirce-Cottler, SM and Papin, JA and Ford, RM}, title = {Spatial transcriptome-guided multi-scale framework connects P. aeruginosa metabolic states to oxidative stress biofilm microenvironment.}, journal = {PLoS computational biology}, volume = {20}, number = {4}, pages = {e1012031}, pmid = {38669236}, issn = {1553-7358}, mesh = {*Biofilms/growth &amp; development ; *Pseudomonas aeruginosa/genetics/metabolism/physiology ; *Oxidative Stress/physiology ; *Transcriptome/genetics ; *Models, Biological ; Computational Biology ; Metabolic Networks and Pathways/genetics ; Nitric Oxide/metabolism ; Computer Simulation ; Denitrification ; }, abstract = {With the generation of spatially resolved transcriptomics of microbial biofilms, computational tools can be used to integrate this data to elucidate the multi-scale mechanisms controlling heterogeneous biofilm metabolism. This work presents a Multi-scale model of Metabolism In Cellular Systems (MiMICS) which is a computational framework that couples a genome-scale metabolic network reconstruction (GENRE) with Hybrid Automata Library (HAL), an existing agent-based model and reaction-diffusion model platform. A key feature of MiMICS is the ability to incorporate multiple -omics-guided metabolic models, which can represent unique metabolic states that yield different metabolic parameter values passed to the extracellular models. We used MiMICS to simulate Pseudomonas aeruginosa regulation of denitrification and oxidative stress metabolism in hypoxic and nitric oxide (NO) biofilm microenvironments. Integration of P. aeruginosa PA14 biofilm spatial transcriptomic data into a P. aeruginosa PA14 GENRE generated four PA14 metabolic model states that were input into MiMICS. Characteristic of aerobic, denitrification, and oxidative stress metabolism, the four metabolic model states predicted different oxygen, nitrate, and NO exchange fluxes that were passed as inputs to update the agent's local metabolite concentrations in the extracellular reaction-diffusion model. Individual bacterial agents chose a PA14 metabolic model state based on a combination of stochastic rules, and agents sensing local oxygen and NO. Transcriptome-guided MiMICS predictions suggested microscale denitrification and oxidative stress metabolic heterogeneity emerged due to local variability in the NO biofilm microenvironment. MiMICS accurately predicted the biofilm's spatial relationships between denitrification, oxidative stress, and central carbon metabolism. As simulated cells responded to extracellular NO, MiMICS revealed dynamics of cell populations heterogeneously upregulating reactions in the denitrification pathway, which may function to maintain NO levels within non-toxic ranges. We demonstrated that MiMICS is a valuable computational tool to incorporate multiple -omics-guided metabolic models to mechanistically map heterogeneous microbial metabolic states to the biofilm microenvironment.}, }
@article {pmid38669142, year = {2024}, author = {Kennelly, C and Tran, P and Prindle, A}, title = {Environmental purines decrease Pseudomonas aeruginosa biofilm formation by disrupting c-di-GMP metabolism.}, journal = {Cell reports}, volume = {43}, number = {5}, pages = {114154}, pmid = {38669142}, issn = {2211-1247}, support = {R35 GM147170/GM/NIGMS NIH HHS/United States ; }, mesh = {*Pseudomonas aeruginosa/metabolism/physiology ; *Biofilms/growth &amp; development ; *Cyclic GMP/metabolism/analogs &amp; derivatives ; *Purines/metabolism/pharmacology ; Bacterial Proteins/metabolism ; }, abstract = {Cyclic di-guanosine monophosphate (c-di-GMP) is a bacterial second messenger that governs the lifestyle switch between planktonic and biofilm states. While substantial investigation has focused on the proteins that produce and degrade c-di-GMP, less attention has been paid to the potential for metabolic control of c-di-GMP signaling. Here, we show that micromolar levels of specific environmental purines unexpectedly decrease c-di-GMP and biofilm formation in Pseudomonas aeruginosa. Using a fluorescent genetic reporter, we show that adenosine and inosine decrease c-di-GMP even when competing purines are present. We confirm genetically that purine salvage is required for c-di-GMP decrease. Furthermore, we find that (p)ppGpp prevents xanthosine and guanosine from producing an opposing c-di-GMP increase, reinforcing a salvage hierarchy that favors c-di-GMP decrease even at the expense of growth. We propose that purines can act as a cue for bacteria to shift their lifestyle away from the recalcitrant biofilm state via upstream metabolic control of c-di-GMP signaling.}, }
@article {pmid38668646, year = {2024}, author = {Ding, H and Bai, Y and Luo, W and Li, H and Zhu, C and Zhao, X and Sun, H and Wen, Y and Zhang, W and Zhang, S and Wen, B and Wang, R and Zhang, L and Liu, X and Shen, J and Hu, J and Wang, L and Bai, Y and Liao, C and Wu, Y and Wu, X and Ding, K}, title = {Rhein kills Actinobacillus pleuropneumoniae, reduces biofilm formation, and effectively treats bacterial lung infections in mice.}, journal = {Journal of medical microbiology}, volume = {73}, number = {4}, pages = {}, doi = {10.1099/jmm.0.001826}, pmid = {38668646}, issn = {1473-5644}, mesh = {Animals ; *Anthraquinones/pharmacology/therapeutic use ; *Actinobacillus pleuropneumoniae/drug effects/genetics ; *Anti-Bacterial Agents/pharmacology/therapeutic use ; Mice ; *Actinobacillus Infections/drug therapy/microbiology/veterinary ; Swine ; Disease Models, Animal ; Female ; Drugs, Chinese Herbal/pharmacology/therapeutic use ; Lung/microbiology/pathology ; Swine Diseases/drug therapy/microbiology ; }, abstract = {Background. Actinobacillus pleuropneumoniae, a member of the Pasteurellaceae family, is known for its highly infectious nature and is the primary causative agent of infectious pleuropneumonia in pigs. This disease poses a considerable threat to the global pig industry and leads to substantial economic losses due to reduced productivity, increased mortality rates, and the need for extensive veterinary care and treatment. Due to the emergence of multi-drug-resistant strains, Chinese herbal medicine is considered one of the best alternatives to antibiotics due to its unique mechanism of action and other properties. As a type of Chinese herbal medicine, Rhein has the advantages of a wide antibacterial spectrum and is less likely to develop drug resistance, which can perfectly solve the limitations of current antibacterial treatments.Methods. The killing effect of Rhein on A. pleuropneumoniae was detected by fluorescence quantification of differential expression changes of key genes, and scanning electron microscopy was used to observe the changes in A. pleuropneumoniae status after Rhein treatment. Establishing a mouse model to observe the treatment of Rhein after A. pleuropneumoniae infection.Results. Here, in this study, we found that Rhein had a good killing effect on A. pleuropneumoniae and that the MIC was 25 µg ml[-1]. After 3 h of action, Rhein (4×MIC) completely kills A. pleuropneumoniae and Rhein has good stability. In addition, the treatment with Rhein (1×MIC) significantly reduced the formation of bacterial biofilms. Therapeutic evaluation in a murine model showed that Rhein protects mice from A. pleuropneumoniae and relieves lung inflammation. Quantitative RT-PCR (Quantitative reverse transcription polymerase chain reaction is a molecular biology technique that combines both reverse transcription and polymerase chain reaction methods to quantitatively detect the amount of a specific RNA molecule) results showed that Rhein treatment significantly downregulated the expression of the IL-18 (Interleukin refers to a class of cytokines produced by white blood cells), TNF-α, p65 and p38 genes. Along with the downregulation of genes such as IL-18, it means that Rhein has an inhibitory effect on the expression of these genes, thereby reducing the activation of inflammatory cells and the production of inflammatory mediators. This helps reduce inflammation and protects tissue from further damage.Conclusions. This study reports the activity of Rhein against A. pleuropneumoniae and its mechanism, and reveals the ability of Rhein to treat A. pleuropneumoniae infection in mice, laying the foundation for the development of new drugs for bacterial infections.}, }
@article {pmid38668447, year = {2024}, author = {Son, Y and Jin, YB and Cho, EJ and Park, AR and Flores, RA and Nguyen, BT and Lee, SY and Altanzul, B and Park, KI and Min, W and Kim, WH}, title = {Comparative Analysis of Antibiotic Resistance and Biofilm Characteristics of Two Major Enterococcus Species from Poultry Slaughterhouses in South Korea.}, journal = {Veterinary sciences}, volume = {11}, number = {4}, pages = {}, pmid = {38668447}, issn = {2306-7381}, support = {Specialized Graduate School Support Project for Wildlife Disease Specialists//National Institute of Wildlife Disease Control and Prevention/ ; //Gyeongnam Veterinary Service Laboratory/ ; }, abstract = {The spread of antibiotic-resistant Enterococcus in the poultry industry poses significant public health challenges due to multidrug resistance and biofilm formation. We investigated the antibiotic resistance profiles and biofilm characteristics of E. faecalis and E. faecium isolates from chicken meat in poultry slaughterhouses in South Korea. Ninety-six isolates (forty-eight each of E. faecalis and E. faecium) were collected between March and September 2022. Both species were analyzed using MALDI-TOF, PCR, antibiotic susceptibility testing, and biofilm assays. A high level of multidrug resistance was observed in E. faecalis (95.8%) and E. faecium (93.8%), with E. faecium exhibiting a broader range of resistance, particularly to linezolid (52.1%) and rifampicin (47.9%). All E. faecalis isolates formed biofilm in vitro, showing stronger biofilm formation than E. faecium with a significant difference (p < 0.001) in biofilm strength. Specific genes (cob, ccf, and sprE) were found to be correlated with biofilm strength. In E. faecium isolates, biofilm strength was correlated with resistance to linezolid and rifampicin, while a general correlation between antibiotic resistance and biofilm strength was not established. Through analysis, correlations were noted between antibiotics within the same class, while no general trends were evident in other analyzed factors. This study highlights the public health risks posed by multidrug-resistant enterococci collected from poultry slaughterhouses, emphasizing the complexity of the biofilm-resistance relationship and the need for enhanced control measures.}, }
@article {pmid38668437, year = {2024}, author = {Fidelis, CE and Orsi, AM and Freu, G and Gonçalves, JL and Santos, MVD}, title = {Biofilm Formation and Antimicrobial Resistance of Staphylococcus aureus and Streptococcus uberis Isolates from Bovine Mastitis.}, journal = {Veterinary sciences}, volume = {11}, number = {4}, pages = {}, pmid = {38668437}, issn = {2306-7381}, abstract = {This study aimed to assess (a) the biofilm producer ability and antimicrobial resistance profiles of Staphylococcus (Staph.) aureus and Streptococcus (Strep.) uberis isolated from cows with clinical mastitis (CM) and subclinical mastitis (SCM), and (b) the association between biofilm producer ability and antimicrobial resistance. We isolated a total of 197 Staph. aureus strains (SCM = 111, CM = 86) and 119 Strep. uberis strains (SCM = 15, CM = 104) from milk samples obtained from 316 cows distributed in 24 dairy herds. Biofilm-forming ability was assessed using the microplate method, while antimicrobial susceptibility was determined using the disk diffusion method against 13 antimicrobials. Among the isolates examined, 57.3% of Staph. aureus and 53.8% of Strep. uberis exhibited the ability to produce biofilm, which was categorized as strong, moderate, or weak. In terms of antimicrobial susceptibility, Staph. aureus isolates displayed resistance to penicillin (92.9%), ampicillin (50.8%), and tetracycline (52.7%). Conversely, Strep. uberis isolates exhibited resistance to penicillin (80.6%), oxacillin (80.6%), and tetracycline (37.8%). However, no significant correlation was found between antimicrobial resistance patterns and biofilm formation ability among the isolates.}, }
@article {pmid38668297, year = {2024}, author = {Bueno-Silva, B and Parma-Garcia, J and Frigo, L and Suárez, LJ and Macedo, TT and Uyeda, FH and Melo, MARDC and Sacco, R and Mourão, CF and Feres, M and Shibli, JA and Figueiredo, LC}, title = {Antimicrobial Activity of Methylene Blue Associated with Photodynamic Therapy: In Vitro Study in Multi-Species Oral Biofilm.}, journal = {Pathogens (Basel, Switzerland)}, volume = {13}, number = {4}, pages = {}, pmid = {38668297}, issn = {2076-0817}, support = {# 311368/2019-0 CNPq//National Council for Scientific and Technological Development/ ; #001 CAPES//Coordination for the Improvement of Higher Education Personel,/ ; }, abstract = {The control of infectious diseases caused by biofilms is a continuing challenge for researchers due to the complexity of their microbial structures and therapeutic implications. Photodynamic therapy as an adjunctive anti-infective treatment has been described as a possible valid approach but has not been tested in polymicrobial biofilm models. This study evaluated the effect of photodynamic therapy in vitro with methylene blue (MB) 0.01% and red LEDs (λ = 660 nm, power density ≈ 330 mW/cm[2], 2 mm distance from culture) on the metabolic activity and composition of a multispecies subgingival biofilm. Test Groups LED and MB + LED showed a more significant reduction in metabolic activity than the non-LED application group (~50 and 55%, respectively). Groups LED and MB equally affected (more than 80%) the total bacterial count in biofilms. No differences were noted in the bacterial biofilm composition between the groups. In vitro LED alone or the MB + LED combination reduced the metabolic activity of bacteria in polymicrobial biofilms and the total subgingival biofilm count.}, }
@article {pmid38668282, year = {2024}, author = {Aljaafari, HAS and Abdulwahhab, NI and Nuxoll, E}, title = {Antibiotic Augmentation of Thermal Eradication of Staphylococcus epidermidis Biofilm Infections.}, journal = {Pathogens (Basel, Switzerland)}, volume = {13}, number = {4}, pages = {}, pmid = {38668282}, issn = {2076-0817}, support = {18IPA34170108//American Heart Association/ ; CBET-1133297//National Science Foundation/ ; }, abstract = {Staphylococcus epidermidis is a major contributor to bacterial infections on medical implants, currently treated by surgical removal of the device and the surrounding infected tissue at considerable morbidity and expense. In situ hyperthermia is being investigated as a non-invasive means of mitigating these bacterial biofilm infections, but minimizing damage to the surrounding tissue requires augmenting the thermal shock with other approaches such as antibiotics and discerning the minimum shock required to eliminate the biofilm. S. epidermidis biofilms were systematically shocked at a variety of temperatures (50-80 °C) and durations (1-10 min) to characterize their thermal susceptibility and compare it to other common nosocomial pathogens such as Staphylococcus aureus and Pseudomonas aeruginosa. Biofilms were also exposed to three classes of antibiotics (ciprofloxacin, tobramycin and erythromycin) separately at concentrations ranging from 0 to 128 μg mL[-1] to evaluate their impact on the efficacy of thermal shock and the subsequent potential regrowth of the biofilm. S. epidermidis biofilms were shown to be more thermally susceptible to hyperthermia than other common bacterial pathogens. All three antibiotics substantially decreased the duration and/or temperature needed to eliminate the biofilms, though this augmentation did not meet the criteria of synergism immediately following thermal shock. Subsequent reincubation, however, revealed strong synergism on a longer timescale.}, }
@article {pmid38668281, year = {2024}, author = {Olayiwola, B and O'Neill, F and Frewen, C and Kavanagh, DF and O'Hara, R and O'Neill, L}, title = {Cold Plasma Deposition of Tobramycin as an Approach to Localized Antibiotic Delivery to Combat Biofilm Formation.}, journal = {Pathogens (Basel, Switzerland)}, volume = {13}, number = {4}, pages = {}, pmid = {38668281}, issn = {2076-0817}, support = {EBPPG/2021/105//Irish Research Council/ ; }, abstract = {Hospital-acquired infections (HAIs) remain a significant factor in hospitals, with implant surfaces often becoming contaminated by highly resistant strains of bacteria. Recent studies have shown that electrical plasma discharges can reduce bacterial load on surfaces, and this approach may help augment traditional antibiotic treatments. To investigate this, a cold atmospheric plasma was used to deposit tobramycin sulphate onto various surfaces, and the bacterial growth rate of K. pneumoniae in its planktonic and biofilm form was observed to probe the interactions between the plasma discharge and the antibiotic and to determine if there were any synergistic effects on the growth rate. The plasma-deposited tobramycin was still active after passing through the plasma field and being deposited onto titanium or polystyrene. This led to the significant inhibition of K. pneumoniae, with predictable antibiotic dose dependence. Separate studies have shown that the plasma treatment of the biofilm had a weak antimicrobial effect and reduced the amount of biofilm by around 50%. Combining a plasma pre-treatment on exposed biofilm followed by deposited tobramycin application proved to be somewhat effective in further reducing biofilm growth. The plasma discharge pre-treatment produced a further reduction in the biofilm load beyond that expected from just the antibiotic alone. However, the effect was not additive, and the results suggest that a complex interaction between plasma and antibiotic may be at play, with increasing plasma power producing a non-linear effect. This study may contribute to the treatment of infected surgical sites, with the coating of biomaterial surfaces with antibiotics reducing overall antibiotic use through the targeted delivery of therapeutics.}, }
@article {pmid38668275, year = {2024}, author = {Araújo, D and Silva, AR and Fernandes, R and Serra, P and Barros, MM and Campos, AM and Oliveira, R and Silva, S and Almeida, C and Castro, J}, title = {Emerging Approaches for Mitigating Biofilm-Formation-Associated Infections in Farm, Wild, and Companion Animals.}, journal = {Pathogens (Basel, Switzerland)}, volume = {13}, number = {4}, pages = {}, pmid = {38668275}, issn = {2076-0817}, support = {LA/P/0045/2020//Funda&#xe7;&#xe3;o para a Ci&#xea;ncia e Tecnologia/ ; UIDB/00511/2020//Funda&#xe7;&#xe3;o para a Ci&#xea;ncia e Tecnologia/ ; UIDB/04469/2020//Funda&#xe7;&#xe3;o para a Ci&#xea;ncia e Tecnologia/ ; UIDB/04033/2020//Funda&#xe7;&#xe3;o para a Ci&#xea;ncia e Tecnologia/ ; UIDP/04033/2020//Funda&#xe7;&#xe3;o para a Ci&#xea;ncia e Tecnologia/ ; https://doi.org/10.54499/2022.06886.CEECIND/CP1737/CT0001//Funda&#xe7;&#xe3;o para a Ci&#xea;ncia e Tecnologia/ ; }, abstract = {The importance of addressing the problem of biofilms in farm, wild, and companion animals lies in their pervasive impact on animal health and welfare. Biofilms, as resilient communities of microorganisms, pose a persistent challenge in causing infections and complicating treatment strategies. Recognizing and understanding the importance of mitigating biofilm formation is critical to ensuring the welfare of animals in a variety of settings, from farms to the wild and companion animals. Effectively addressing this issue not only improves the overall health of individual animals, but also contributes to the broader goals of sustainable agriculture, wildlife conservation, and responsible pet ownership. This review examines the current understanding of biofilm formation in animal diseases and elucidates the complex processes involved. Recognizing the limitations of traditional antibiotic treatments, mechanisms of resistance associated with biofilms are explored. The focus is on alternative therapeutic strategies to control biofilm, with illuminating case studies providing valuable context and practical insights. In conclusion, the review highlights the importance of exploring emerging approaches to mitigate biofilm formation in animals. It consolidates existing knowledge, highlights gaps in understanding, and encourages further research to address this critical facet of animal health. The comprehensive perspective provided by this review serves as a foundation for future investigations and interventions to improve the management of biofilm-associated infections in diverse animal populations.}, }
@article {pmid38668260, year = {2024}, author = {Silva, A and Silva, V and Dapkevicius, MLE and Azevedo, M and Cordeiro, R and Pereira, JE and Valentão, P and Falco, V and Igrejas, G and Caniça, M and Poeta, P}, title = {Unveiling Antibiotic Resistance, Clonal Diversity, and Biofilm Formation in E. coli Isolated from Healthy Swine in Portugal.}, journal = {Pathogens (Basel, Switzerland)}, volume = {13}, number = {4}, pages = {}, pmid = {38668260}, issn = {2076-0817}, abstract = {Escherichia coli, a commensal microorganism found in the gastrointestinal tract of human and animal hosts, plays a central role in agriculture and public health. Global demand for animal products has promoted increased pig farming, leading to growing concerns about the prevalence of antibiotic-resistant E. coli strains in swine populations. It should be noted that a significant portion of antibiotics deployed in swine management belong to the critically important antibiotics (CIA) class, which should be reserved for human therapeutic applications. This study aimed to characterize the prevalence of antibiotic resistance, genetic diversity, virulence characteristics, and biofilm formation of E. coli strains in healthy pigs from various farms across central Portugal. Our study revealed high levels of antibiotic resistance, with resistance to tetracycline, ampicillin, tobramycin, and trimethoprim-sulfamethoxazole. Multidrug resistance is widespread, with some strains resistant to seven different antibiotics. The ampC gene, responsible for broad-spectrum resistance to cephalosporins and ampicillin, was widespread, as were genes associated with resistance to sulfonamide and beta-lactam antibiotics. The presence of high-risk clones, such as ST10, ST101, and ST48, are a concern due to their increased virulence and multidrug resistance profiles. Regarding biofilm formation, it was observed that biofilm-forming capacity varied significantly across different compartments within pig farming environments. In conclusion, our study highlights the urgent need for surveillance and implementation of antibiotic management measures in the swine sector. These measures are essential to protect public health, ensure animal welfare, and support the swine industry in the face of the growing global demand for animal products.}, }
@article {pmid38667020, year = {2024}, author = {El Haj, C and Agustí, E and Benavent, E and Soldevila-Boixader, L and Rigo-Bonnin, R and Tubau, F and Torrejón, B and Esteban, J and Murillo, O}, title = {Comparative Efficacy of Continuous Ceftazidime Infusion vs. Intermittent Bolus against In Vitro Ceftazidime-Susceptible and -Resistant Pseudomonas aeruginosa Biofilm.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {4}, pages = {}, pmid = {38667020}, issn = {2079-6382}, support = {PI19/00965//Instituto de Salud Carlos III/ ; }, abstract = {Background: As the anti-biofilm pharmacokinetic/pharmacodynamic (PK/PD) properties of antibiotics are not well-defined, we have evaluated the PK/PD indices for different regimens of ceftazidime (CAZ; with/without colistin) against Pseudomonas aeruginosa biofilm. Methods: We have used the Center for Disease Control and Prevention Biofilm Reactor with two susceptible (PAO1 and HUB-PAS) and one resistant (HUB-XDR) strains of P. aeruginosa. The regimens were CAZ monotherapies (mimicking a human dose of 2 g/8 h, CAZ-IB; 6 g/daily as continuous infusion at 50 mg/L, CAZ-CI50; and 9 g/daily at 70 mg/L, CAZ-CI70) and CAZ-colistin combinations. Efficacy was correlated with the CAZ PK/PD parameters. Results: CAZ-CI70 was the most effective monotherapy against CAZ-susceptible strains (Δlog CFU/mL 54-0 h = -4.15 ± 0.59 and -3.05 ± 0.5 for HUB-PAS and PAO1, respectively; p ≤ 0.007 vs. other monotherapies), and adding colistin improved the efficacy over CAZ monotherapy. CAZ monotherapies were ineffective against the HUB-XDR strain, and CAZ-CI50 plus colistin achieved higher efficacy than CAZ-IB with colistin. The PK/PD index that correlated best with anti-biofilm efficacy was fAUC0-24h/MIC (r[2] = 0.78). Conclusions: CAZ exhibited dose-dependent anti-biofilm killing against P. aeruginosa, which was better explained by the fAUC0-24h/MIC index. CAZ-CI provided benefits compared to CAZ-IB, particularly when using higher doses and together with colistin. CAZ monotherapies were ineffective against the CAZ-resistant strain, independently of the optimized strategy and only CAZ-CI plus colistin appeared useful for clinical practice.}, }
@article {pmid38666994, year = {2024}, author = {Mazzantini, D and Massimino, M and Calvigioni, M and Rossi, V and Celandroni, F and Lupetti, A and Batoni, G and Ghelardi, E}, title = {Anti-Staphylococcal Biofilm Effects of a Liposome-Based Formulation Containing Citrus Polyphenols.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {4}, pages = {}, pmid = {38666994}, issn = {2079-6382}, support = {PNRR THE-Tuscany Health Ecosystem; Spoke 7-Innovating Translational Medicine-Sub-project 5-Innovative models for management of infections caused by antibiotic-resistant bacteria (Project code: ECS00000017; CUP I53C22000780001)//European Commission/ ; }, abstract = {Biofilms are surface-associated microbial communities embedded in a matrix that is almost impenetrable to antibiotics, thus constituting a critical health threat. Biofilm formation on the cornea or ocular devices can lead to serious and difficult-to-treat infections. Nowadays, natural molecules with antimicrobial activity and liposome-based delivery systems are proposed as anti-biofilm candidates. In this study, the anti-biofilm activity of a formulation containing citrus polyphenols encapsulated in liposomes was evaluated against Staphylococcus aureus and Staphylococcus epidermidis, the most common agents in ocular infections. The formulation activity against planktonic staphylococci was tested by broth microdilution and sub-inhibitory concentrations were used to evaluate the effect on biofilm formation using the crystal violet (CV) assay. The eradicating effect of the preparation on mature biofilms was investigated by the CV assay, plate count, and confocal laser scanning microscopy. The product was bactericidal against staphylococci at a dilution of 1:2 or 1:4 and able to reduce biofilm formation even if diluted at 1:64. The formulation also had the ability to reduce the biomass of mature biofilms without affecting the number of cells, suggesting activity on the extracellular matrix. Overall, our results support the application of the used liposome-encapsulated polyphenols as an anti-biofilm strategy to counter biofilm-associated ocular infections.}, }
@article {pmid38666986, year = {2024}, author = {Sumlu, E and Aydin, M and Korucu, EN and Alyar, S and Nsangou, AM}, title = {Artemisinin May Disrupt Hyphae Formation by Suppressing Biofilm-Related Genes of Candida albicans: In Vitro and In Silico Approaches.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {4}, pages = {}, pmid = {38666986}, issn = {2079-6382}, abstract = {This study aimed to assess the antifungal and antibiofilm efficacy of artemisinin against Candida (C.) species, analyze its impact on gene expression levels within C. albicans biofilms, and investigate the molecular interactions through molecular docking. The antifungal efficacy of artemisinin on a variety of Candida species, including fluconazole-resistant and -susceptible species, was evaluated by the microdilution method. The effect of artemisinin on C. albicans biofilm formation was investigated by MTT and FESEM. The mRNA expression of the genes related to biofilm was analyzed by qRT-PCR. In addition, molecular docking analysis was used to understand the interaction between artemisinin and C. albicans at the molecular level with RAS1-cAMP-EFG1 and EFG1-regulated genes. Artemisinin showed higher sensitivity against non-albicans Candida strains. Furthermore, artemisinin was strongly inhibitory against C. albicans biofilms at 640 µg/mL. Artemisinin downregulated adhesion-related genes ALS3, HWP1, and ECE1, hyphal development genes UME6 and HGC1, and hyphal CAMP-dependent protein kinase regulators CYR1, RAS1, and EFG1. Furthermore, molecular docking analysis revealed that artemisinin and EFG1 had the highest affinity, followed by UME6. FESEM analysis showed that the fluconazole- and artemisinin-treated groups exhibited a reduced hyphal network, unusual surface bulges, and the formation of pores on the cell surfaces. Our study suggests that artemisinin may have antifungal potential and showed a remarkable antibiofilm activity by significantly suppressing adhesion and hyphal development through interaction with key proteins involved in biofilm formation, such as EFG1.}, }
@article {pmid38666917, year = {2024}, author = {Vang, D and Moreira-Souza, ACA and Zusman, N and Moncada, G and Matshik Dakafay, H and Asadi, H and Ojcius, DM and Almeida-da-Silva, CLC}, title = {Frankincense (Boswellia serrata) Extract Effects on Growth and Biofilm Formation of Porphyromonas gingivalis, and Its Intracellular Infection in Human Gingival Epithelial Cells.}, journal = {Current issues in molecular biology}, volume = {46}, number = {4}, pages = {2991-3004}, pmid = {38666917}, issn = {1467-3045}, support = {Intramural funds//University of the Pacific/ ; Start-Up Funds (D30059 - Activity 101)//University of the Pacific/ ; }, abstract = {Frankincense is produced by Boswellia trees, which can be found throughout the Middle East and parts of Africa and Asia. Boswellia serrata extract has been shown to have anti-cancer, anti-inflammatory, and antimicrobial effects. Periodontitis is an oral chronic inflammatory disease that affects nearly half of the US population. We investigated the antimicrobial effects of B. serrata extract on two oral pathogens associated with periodontitis. Using the minimum inhibitory concentration and crystal violet staining methods, we demonstrated that Porphyromonas gingivalis growth and biofilm formation were impaired by treatment with B. serrata extracts. However, the effects on Fusobacterium nucleatum growth and biofilm formation were not significant. Using quantification of colony-forming units and microscopy techniques, we also showed that concentrations of B. serrata that were not toxic for host cells decreased intracellular P. gingivalis infection in human gingival epithelial cells. Our results show antimicrobial activity of a natural product extracted from Boswellia trees (B. serrata) against periodontopathogens. Thus, B. serrata has the potential for preventing and/or treating periodontal diseases. Future studies will identify the molecular components of B. serrata extracts responsible for the beneficial effects.}, }
@article {pmid38663906, year = {2024}, author = {Zhu, J and Fan, X and Ding, L and Song, T}, title = {Idiopathic gingival fibromatosis and primary analysis of dominant bacteria in subgingival biofilm: a case report.}, journal = {The Journal of international medical research}, volume = {52}, number = {4}, pages = {3000605241245302}, pmid = {38663906}, issn = {1473-2300}, mesh = {Adult ; Humans ; Male ; Bacteria/isolation &amp; purification ; *Biofilms/growth &amp; development ; *Fibromatosis, Gingival/diagnosis/pathology/microbiology ; *Gingiva/microbiology/pathology ; Gingivectomy/methods ; }, abstract = {Idiopathic gingival fibromatosis (IGF), a rare fibroproliferative disease of unknown etiology, affects gingival tissue and has substantial adverse effects on patients. Therefore, the pathogenesis of IGF requires more extensive and in-depth research. In this case, a patient with confirmed IGF underwent initial nonsurgical periodontal therapy and gingivectomy, and the prognosis was good. The patient had no loss of periodontal attachment but had a history of swelling and bleeding of the gingiva prior to fibrous enlargement, which prompted further investigation. We explored the patient's subgingival microbiome and found a high abundance of periodontal pathogens. Gingival tissue biopsy revealed abundant fibrous tissue containing multiple inflammatory cell infiltrates. These results suggest that gingival inflammation secondary to periodontal pathogens can contribute to IGF onset.}, }
@article {pmid38663668, year = {2024}, author = {Zheng, C and Zhang, J and Ni, M and Pan, Y}, title = {Phosphate recovery from urban sewage by the biofilm sequencing batch reactor process: Key factors in biofilm formation and related mechanisms.}, journal = {Environmental research}, volume = {252}, number = {Pt 3}, pages = {118985}, doi = {10.1016/j.envres.2024.118985}, pmid = {38663668}, issn = {1096-0953}, mesh = {*Biofilms/growth &amp; development ; *Bioreactors/microbiology ; *Sewage/microbiology/chemistry ; *Phosphates/metabolism/analysis ; Waste Disposal, Fluid/methods ; Phosphorus/analysis/metabolism ; }, abstract = {The biofilm sequencing batch reactor (BSBR) technique has been deployed in the laboratory to enrich phosphorus from simulated wastewater, but it is still not clear what its performance will be when real world sewage is used. In this work, the effluent from the multi-stage anoxic-oxic (AO) activated sludge process at a sewage plant was used as the feed water for a BSBR pilot system, which had three reactors operating at different levels of dissolved oxygen (DO). The phosphorus adsorption and release, the biofilm growth, and the extracellular polymeric substances (EPS) components and contents were examined. The microbial communities and the signaling molecules N-acyl-l-homoserine lactones (AHLs) were also analyzed. Gratifyingly, the BSBR process successfully processed the treated sewage, and the biofilm developed phosphorus accumulation capability within 40 days. After entering stable operation, the system concentrated phosphate from 2.59 ± 0.77 mg/L in the influent to as much as 81.64 mg/L in the recovery liquid. Sludge discharge had profound impacts on all aspects of BSBR, and it was carried out successfully when the phosphorus absorption capacity of the biofilm alone was comparable to that of the reactor containing the activated sludge. Shortly after the sludge discharge, the phosphate concentration of the recovery liquid surged from 50 to 140 mg/L, the biofilm thickness grew from 20.56 to 67.32 μm, and the diversity of the microbial population plunged. Sludge discharge stimulated Candidatus competibacter to produce a large amount of AHLs, which was key in culturing the biofilm. Among the AHLs, both C10-HSL and 3OC12-HSL were significantly positively correlated with EPS and the abundance of Candidatus competibacter. The current results demonstrated BSBR as a viable option to enrich phosphorus from real world sewage with low phosphorus content and fluctuating chemistry. The mechanistic explorations also provided theoretical guidance for cultivating phosphorus-accumulating biofilms.}, }
@article {pmid38663625, year = {2024}, author = {Xu, F and Jiang, M and Li, D and Yu, P and Ma, H and Lu, H}, title = {Protective effects of antibiotic resistant bacteria on susceptibles in biofilm: Influential factors, mechanism, and modeling.}, journal = {The Science of the total environment}, volume = {930}, number = {}, pages = {172668}, doi = {10.1016/j.scitotenv.2024.172668}, pmid = {38663625}, issn = {1879-1026}, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology ; *Escherichia coli/drug effects/physiology ; Drug Resistance, Bacterial ; Ampicillin/pharmacology ; Microbial Sensitivity Tests ; Soil Microbiology ; }, abstract = {In environmental biofilms, antibiotic-resistant bacteria facilitate the persistence of susceptible counterparts under antibiotic stresses, contributing to increased community-level resistance. However, there is a lack of quantitative understanding of this protective effect and its influential factors, hindering accurate risk assessment of biofilm resistance in diverse environment. This study isolated an opportunistic Escherichia coli pathogen from soil, and engineered it with plasmids conferring antibiotic resistance. Protective effects of the ampicillin resistant strain (AmpR) on their susceptible counterparts (AmpS) were observed in ampicillin-stress colony biofilms. The concentration of ampicillin delineated protective effects into 3 zones: continuous protection (<1 MIC of AmpS), initial AmpS/R dependent (1-8 MIC of AmpS), and ineffective (>8 MIC of AmpS). Intriguingly, Zone 2 exhibited a surprising "less is more" phenomenon tuned by the initial AmpS/R ratio, where biofilm with an initially lower AmpR (1:50 vs 50:1) harbored 30-90 % more AmpR after 24 h growth under antibiotic stress. Compared to AmpS, AmpR displayed superiority in adhesion, antibiotic degradation, motility, and quorum sensing, allowing them to preferentially colonize biofilm edge and areas with higher ampicillin. An agent-based model incorporating protective effects successfully simulated tempo-spatial dynamics of AmpR and AmpS influenced by antibiotic stress and initial AmpS/R. This study provides a holistic view on the pervasive but poorly understood protective effects in biofilm, enabling development of better risk assessment and precisely targeted control strategies of biofilm resistance in diverse environment.}, }
@article {pmid38663447, year = {2024}, author = {Zhang, Z and Ma, J and Xu, T and Wang, T and Jia, X and Lin, J and Lv, C and Cao, L and Ying, Y and Ji, L and Wang, S and Fu, C}, title = {Transpiration-Inspired Fabric Dressing for Acceleration Healing of Wound Infected with Biofilm.}, journal = {Advanced healthcare materials}, volume = {13}, number = {23}, pages = {e2401005}, doi = {10.1002/adhm.202401005}, pmid = {38663447}, issn = {2192-2659}, support = {//521 Talent Project of Zhejiang Sci-Tech University/ ; LZ22C100002//Natural Science Foundation of Zhejiang Province/ ; LQ22B010006//Natural Science Foundation of Zhejiang Province/ ; }, mesh = {*Biofilms/drug effects ; *Bandages ; *Wound Healing/drug effects ; *Titanium/chemistry ; *Staphylococcus aureus/drug effects/physiology ; *Textiles ; Animals ; Anti-Bacterial Agents/pharmacology/chemistry ; Staphylococcal Infections/drug therapy ; Polyethylene Terephthalates/chemistry ; Wound Infection/microbiology/drug therapy/therapy ; Nanostructures/chemistry ; Biomimetic Materials/chemistry/pharmacology ; Humans ; }, abstract = {In chronic wound management, efficacious handling of exudate and bacterial infections stands as a paramount challenge. Here a novel biomimetic fabric, inspired by the natural transpiration mechanisms in plants, is introduced. Uniquely, the fabric combines a commercial polyethylene terephthalate (PET) fabric with asymmetrically grown 1D rutile titanium dioxide (TiO2) micro/nanostructures, emulating critical plant features: hierarchically porous networks and hydrophilic water conduction channels. This structure endows the fabric with exceptional antigravity wicking-evaporation performance, evidenced by a 780% one-way transport capability and a 0.75 g h[-1] water evaporation rate, which significantly surpasses that of conventional moisture-wicking textiles. Moreover, the incorporated 1D rutile TiO2 micro/nanostructures present solar-light induced antibacterial activity, crucial for disrupting and eradicating wound biofilms. The biomimetic transpiration fabric is employed to drain exudate and eradicate biofilms in Staphylococcus aureus (S. aureus)-infected wounds, demonstrating a much faster infection eradication capability compared to clinically common ciprofloxacin irrigation. These findings illuminate the path for developing high-performance, textile-based wound dressings, offering efficient clinical platforms to combat biofilms associated with chronic wounds.}, }
@article {pmid38661711, year = {2024}, author = {Souza, V and Polaquini, CR and de Moraes, GR and Oliveira Braga, AR and da Silva, PV and da Silva, DR and Ribeiro Lima, FR and Regasini, LO and Cássia Orlandi Sardi, J}, title = {Diacetylcurcumin: a novel strategy against Enterococcus faecalis biofilm in root canal disinfection.}, journal = {Future microbiology}, volume = {19}, number = {8}, pages = {647-654}, pmid = {38661711}, issn = {1746-0921}, mesh = {*Biofilms/drug effects ; *Enterococcus faecalis/drug effects/physiology ; *Curcumin/pharmacology/analogs &amp; derivatives/chemistry ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology/chemistry ; Animals ; *Moths/drug effects/microbiology ; Disinfection/methods ; Drug Synergism ; Calcium Hydroxide/pharmacology ; Dental Pulp Cavity/microbiology ; }, abstract = {Aim: We evaluated Diacetylcurcumin (DAC), a derivative of curcumin, for its antibacterial and antibiofilm properties against Enterococcus faecalis. Methods: Minimum inhibitory concentration (MIC) and minimum bactericidal concentration were determined, along with antibiofilm potential and toxicity in Galleria mellonella. Additionally, in silico computational analysis was performed to understand its mechanisms of action. Results &amp; conclusion: DAC demonstrated significant antibacterial effects, with MIC and MBC values of 15.6 and 31.25 μg/ml, respectively, and reduced biofilm formation. A synergistic effect, reducing biofilm by 77%, was observed when combined with calcium hydroxide. G. mellonella toxicity tests confirmed DAC's safety at tested concentrations, suggesting its potential for use in root canal disinfection products.}, }
@article {pmid38660899, year = {2024}, author = {Li, YY and Liu, HC and Wang, HP and DU, TY and Jiang, L}, title = {[Characteristics of drug resistance and biofilm formation in carbapenem-resistant Acinetobacter baumannii in hospitalized children].}, journal = {Zhongguo dang dai er ke za zhi = Chinese journal of contemporary pediatrics}, volume = {26}, number = {4}, pages = {358-364}, pmid = {38660899}, issn = {1008-8830}, mesh = {*Acinetobacter baumannii/drug effects/genetics ; *Biofilms/drug effects ; *Carbapenems/pharmacology ; Humans ; Child ; *Acinetobacter Infections/microbiology ; Child, Preschool ; beta-Lactamases/genetics ; Child, Hospitalized ; Drug Resistance, Bacterial/genetics ; Anti-Bacterial Agents/pharmacology ; Female ; Infant ; Male ; Microbial Sensitivity Tests ; Bacterial Proteins/genetics ; }, abstract = {OBJECTIVES: To study the distribution, drug resistance, and biofilm characteristics of carbapenem-resistant Acinetobacter baumannii (CRAB) isolated from hospitalized children, providing a reference for the prevention and treatment of CRAB infections in hospitalized children.<br><br>METHODS: Forty-eight CRAB strains isolated from January 2019 to December 2022 were classified into epidemic and sporadic strains using repetitive extragenic palindromic sequence-based polymerase chain reaction. The drug resistance, biofilm phenotypes, and gene carriage of these two types of strains were compared.<br><br>RESULTS: Both the 22 epidemic strains and the 26 sporadic strains were producers of Class D carbapenemases or extended-spectrum &#x3b2;-lactamases with downregulated outer membrane porins, harboring the VIM, OXA-23, and OXA-51 genes. The biofilm formation capability of the sporadic strains was stronger than that of the epidemic strains (P<0.05). Genes related to biofilm formation, including Bap, bfs, OmpA, CsuE, and intI1, were detected in both epidemic and sporadic strains, with a higher detection rate of the intI1 gene in epidemic strains (P<0.05).<br><br>CONCLUSIONS: CRAB strains are colonized in the hospital, with sporadic strains having a stronger ability to form biofilms, suggesting the potential for forming new clonal transmissions in the hospital. Continuous monitoring of the epidemic trends of CRAB and early warning of the distribution of epidemic strains are necessary to reduce the risk of CRAB infections in hospitalized children.}, }
@article {pmid38659983, year = {2024}, author = {Alharbi, NK and Azeez, ZF and Alhussain, HM and Shahlol, AMA and Albureikan, MOI and Elsehrawy, MG and Aloraini, GS and El-Nablaway, M and Khatrawi, EM and Ghareeb, A}, title = {Tapping the biosynthetic potential of marine Bacillus licheniformis LHG166, a prolific sulphated exopolysaccharide producer: structural insights, bio-prospecting its antioxidant, antifungal, antibacterial and anti-biofilm potency as a novel anti-infective lead.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1385493}, pmid = {38659983}, issn = {1664-302X}, abstract = {The escalating global threat of antimicrobial resistance necessitates prospecting uncharted microbial biodiversity for novel therapeutic leads. This study mines the promising chemical richness of Bacillus licheniformis LHG166, a prolific exopolysaccharide (EPSR2-7.22 g/L). It comprised 5 different monosaccharides with 48.11% uronic acid, 17.40% sulfate groups, and 6.09% N-acetyl glucosamine residues. EPSR2 displayed potent antioxidant activity in DPPH and ABTS[+], TAC and FRAP assays. Of all the fungi tested, the yeast Candida albicans displayed the highest susceptibility and antibiofilm inhibition. The fungi Aspergillus niger and Penicillium glabrum showed moderate EPSR2 susceptibility. In contrast, the fungi Mucor circinelloides and Trichoderma harzianum were resistant. Among G+ve tested bacteria, Enterococcus faecalis was the most susceptible, while Salmonella typhi was the most sensitive to G-ve pathogens. Encouragingly, EPSR2 predominantly demonstrated bactericidal effects against both bacterial classes based on MBC/MIC of either 1 or 2 superior Gentamicin. At 75% of MBC, EPSR2 displayed the highest anti-biofilm activity of 88.30% against B. subtilis, while for G-ve antibiofilm inhibition, At 75% of MBC, EPSR2 displayed the highest anti-biofilm activity of 96.63% against Escherichia coli, Even at the lowest dose of 25% MBC, EPSR2 reduced biofilm formation by 84.13% in E. coli, 61.46% in B. subtilis. The microbial metabolite EPSR2 from Bacillus licheniformis LHG166 shows promise as an eco-friendly natural antibiotic alternative for treating infections and oxidative stress.}, }
@article {pmid38659587, year = {2024}, author = {Chen, Q and Dong, Z and Yao, X and Sun, H and Pan, X and Liu, J and Huang, R}, title = {Bactericidal and biofilm eradication efficacy of a fluorinated benzimidazole derivative, TFBZ, against methicillin-resistant Staphylococcus aureus.}, journal = {Frontiers in pharmacology}, volume = {15}, number = {}, pages = {1342821}, pmid = {38659587}, issn = {1663-9812}, abstract = {Methicillin-resistant Staphylococcus aureus (MRSA) is a major inducement of nosocomial infections and its biofilm formation render the high tolerance to conventional antibiotics, which highlights the requirement to develop new antimicrobial agents urgently. In this study, we identified a fluorinated benzimidazole derivative, TFBZ, with potent antibacterial efficacy toward planktonic MRSA (MIC = 4 μg/mL, MBC = 8 μg/mL) and its persistent biofilms (≥99%, MBEC = 8 μg/mL). TFBZ manifested significant irreversible time-dependent killing against MRSA as characterized by diminished cell viability, bacterial morphological change and protein leakage. Furthermore, the results from CBD devices, crystal violet assay in conjunction with live/dead staining and scanning electron microscopy confirmed that TFBZ was capable of eradicating preformed MRSA biofilms with high efficiency. Simultaneously, TFBZ reduced the bacterial invasiveness and exerted negligible hemolysis and cytotoxicity toward mammalian cells, which ensuring the robust therapeutic effect on mouse skin abscess model. The transcriptome profiling and quantitative RT-PCR revealed that a set of encoding genes associated with cell adhesion, biofilm formation, translation process, cell wall biosynthesis was consistently downregulated in MRSA biofilms upon exposure to TFBZ. In conclusion, TFBZ holds promise as a valuable candidate for therapeutic applications against MRSA chronic infections.}, }
@article {pmid38658316, year = {2024}, author = {Cassola, F and Ramírez, N and Delarmelina, C and Duarte, MCT}, title = {In vitro determination of the susceptibility of Malassezia furfur biofilm to different commercially used antimicrobials.}, journal = {APMIS : acta pathologica, microbiologica, et immunologica Scandinavica}, volume = {132}, number = {12}, pages = {1106-1114}, doi = {10.1111/apm.13419}, pmid = {38658316}, issn = {1600-0463}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Malassezia/drug effects ; *Microbial Sensitivity Tests ; *Antifungal Agents/pharmacology ; Humans ; Microscopy, Electron, Scanning ; Dermatitis, Seborrheic/microbiology/drug therapy ; }, abstract = {Malassezia furfur is a yeast known as the etiological agent of seborrheic dermatitis. We evaluated the action of five different antimicrobials (amphotericin B, chloramphenicol, ketoconazole, fluconazole, and nystatin) on inhibiting biofilm formation and removing biofilm already formed by M. furfur. The assays were carried out using the microdilution method, and scanning electron microscopy images were used to analyze the biofilm structure. According to the results obtained, the percentage of inhibition was higher for chloramphenicol, followed by ketoconazole, nystatin, and amphotericin B. Regarding the eradication of the biofilm formed, the highest percentage was chloramphenicol, followed by ketoconazole and nystatin. Amphotericin B did not affect biofilm eradication, whereas fluconazole did not cause significant changes inhibiting or removing M. furfur biofilm. Therefore, except for fluconazole, all evaluated antimicrobials had inhibiting effects on the biofilm of M. furfur, either in its formation and/or eradication. Although the results achieved with chloramphenicol have been highlighted, further in vitro and in vivo studies are still needed in order to include this antimicrobial in the therapy of seborrheic dermatitis due to its toxicity, especially to the bone marrow.}, }
@article {pmid38658078, year = {2024}, author = {Banerjee, A and Stockbridge, RB and Tenuta, LMA}, title = {Measurement and analysis of microbial fluoride resistance in dental biofilm models.}, journal = {Methods in enzymology}, volume = {696}, number = {}, pages = {155-174}, doi = {10.1016/bs.mie.2023.12.018}, pmid = {38658078}, issn = {1557-7988}, support = {R21 DE032837/DE/NIDCR NIH HHS/United States ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Streptococcus mutans/drug effects/genetics/physiology/metabolism/growth &amp; development ; *Fluorides/pharmacology/metabolism ; *Candida albicans/drug effects/genetics/metabolism/physiology ; *Streptococcus gordonii/drug effects/genetics/physiology ; Humans ; Bacterial Proteins/genetics/metabolism ; Drug Resistance, Bacterial/genetics ; Dental Caries/microbiology ; }, abstract = {The interactions between communities of microorganisms inhabiting the dental biofilm is a major determinant of oral health. These biofilms are periodically exposed to high concentrations of fluoride, which is present in almost all oral healthcare products. The microbes resist fluoride through the action of membrane export proteins. This chapter describes the culture, growth and harvest conditions of model three-species dental biofilm comprised of cariogenic pathogens Streptococcus mutans and Candida albicans and the commensal bacterium Streptococcus gordonii. In order to examine the role of fluoride export by S. mutans in model biofilms, procedures for generating a strain of S. mutans with a genetic knockout of the fluoride exporter are described. We present a case study examining the effects of this mutant strain on the biofilm mass, acid production and mineral dissolution under exposure to low levels of fluoride. These general approaches can be applied to study the effects of any gene of interest in physiologically realistic multispecies oral biofilms.}, }
@article {pmid38657691, year = {2024}, author = {Cerda, &#xc1; and Rodríguez, C and González, M and González, H and Serrano, J and Leiva, E}, title = {Feammox bacterial biofilm formation in HFMB.}, journal = {Chemosphere}, volume = {358}, number = {}, pages = {142072}, doi = {10.1016/j.chemosphere.2024.142072}, pmid = {38657691}, issn = {1879-1298}, mesh = {*Biofilms/growth &amp; development ; *Bioreactors/microbiology ; *Bacteria/metabolism ; *Ammonium Compounds/metabolism ; Iron/metabolism ; Anaerobiosis ; }, abstract = {Nitrogen pollution has been increasing with the development of industrialization. Consequently, the excessive deposition of reactive nitrogen in the environment has generated the loss of biodiversity and eutrophication of different ecosystems. In 2005, a Feammox process was discovered that anaerobically metabolizes ammonium. Feammox with the use of hollow fiber membrane bioreactors (HFMB), based on the formation of biofilms of bacterial communities, has emerged as a possible efficient and sustainable method for ammonium removal in environments with high iron concentrations. This work sought to study the possibility of implementing, at laboratory scale, an efficient method by evaluating the use of HFMB. Samples from an internal circulation reactor (IC) incubated in culture media for Feammox bacteria. The cultures were enriched in a batch reactor to evaluate growth conditions. Next, HFMB assembly was performed, and Feammox parameters were monitored. Also, conventional PCR and scanning electron microscopy (SEM) analysis were performed to characterize the bacterial communities associated with biofilm formation. The use of sodium acetate presented the best performance for Feammox activity. The HFMB operation showed an ammonium (NH4[+]) removal of 50%. SEM analysis of the fibers illustrated the formation of biofilm networks formed by bacteria, which were identified as Albidiferax ferrireducens, Geobacter spp, Ferrovum myxofaciens, Shewanella spp., and Anammox. Functional genes Archaea/Bacteria ammonia monooxygenase, nrxA, hzsB, nirS and nosZ were also identified. The implementation of HFMB Feammox could be used as a sustainable tool for the removal of ammonium from wastewater produced because of anthropogenic activities.}, }
@article {pmid38656598, year = {2025}, author = {Hassan, RM and Yehia, H and El-Behairy, MF and El-Azzouny, AA and Aboul-Enein, MN}, title = {Design and synthesis of new quinazolinone derivatives: investigation of antimicrobial and biofilm inhibition effects.}, journal = {Molecular diversity}, volume = {29}, number = {1}, pages = {21-42}, pmid = {38656598}, issn = {1573-501X}, mesh = {*Biofilms/drug effects ; *Quinazolinones/pharmacology/chemistry/chemical synthesis ; *Pseudomonas aeruginosa/drug effects ; *Drug Design ; *Microbial Sensitivity Tests ; *Molecular Docking Simulation ; *Quorum Sensing/drug effects ; Anti-Bacterial Agents/pharmacology/chemical synthesis/chemistry ; Humans ; Structure-Activity Relationship ; Anti-Infective Agents/pharmacology/chemical synthesis/chemistry ; }, abstract = {New quinazolin-4-ones 9-32 were synthesized in an attempt to overcome the life-threatening antibiotic resistance phenomenon. The antimicrobial screening revealed that compounds 9, 15, 16, 18, 19, 20 and 29 are the most broad spectrum antimicrobial agents in this study with safe profile on human cell lines. Additionally, compounds 19 and 20 inhibited biofilm formation in Pseudomonas aeruginosa, which is regulated by quorum sensing system, at sub-minimum inhibitory concentrations (sub-MICs) with IC50 values 3.55 and 6.86 µM, respectively. By assessing other pseudomonal virulence factors suppression, it was found that compound 20 decreased cell surface hydrophobicity compromising bacterial cells adhesion, while both compounds 19 and 20 curtailed the exopolysaccharide production which constitutes the major component of the matrix binding biofilm components together. Also, at sub-MICs Pseudomonas cells twitching motility was impeded by compounds 19 and 20, a trait which augments the cells pathogenicity and invasion potential. Molecular docking study was performed to further evaluate the binding mode of candidates 19 and 20 as inhibitors of P. aeruginosa quorum sensing transcriptional regulator PqsR. The achieved results demonstrate that both compounds bear promising potential for discovering new anti-biofilm and quorum quenching agents against Pseudomonas aeruginosa without triggering resistance mechanisms as the normal bacterial life cycle is not disturbed.}, }
@article {pmid38656049, year = {2024}, author = {Poker, BC and Oliveira, VC and Macedo, AP and Gonçalves, M and Ramos, AP and Silva-Lovato, CH}, title = {Evaluation of surface roughness, wettability and adhesion of multispecies biofilm on 3D-printed resins for the base and teeth of complete dentures.}, journal = {Journal of applied oral science : revista FOB}, volume = {32}, number = {}, pages = {e20230326}, doi = {10.1590/1678-7757-2023-0326}, pmid = {38656049}, issn = {1678-7765}, mesh = {*Biofilms ; *Surface Properties ; *Printing, Three-Dimensional ; *Streptococcus mutans/physiology ; *Staphylococcus aureus/physiology ; *Candida albicans/physiology ; *Wettability ; *Microscopy, Electron, Scanning ; *Materials Testing ; *Denture Bases/microbiology ; *Microscopy, Confocal ; *Acrylic Resins/chemistry ; *Bacterial Adhesion ; Analysis of Variance ; Reproducibility of Results ; Denture, Complete/microbiology ; Reference Values ; Colony Count, Microbial ; Linear Models ; }, abstract = {OBJECTIVE: This study evaluated the surface roughness, wettability and adhesion of multispecies biofilms (Candida albicans, Staphylococcus aureus and Streptococcus mutans) on 3D-printed resins for complete denture bases and teeth compared to conventional resins (heat-polymerized acrylic resin; artificial pre-fabricated teeth).<br><br>METHODOLOGY: Circular specimens (n=39; 6.0 mm &#xd8; &#xd7; 2.0 mm) of each group were subjected to roughness (n=30), wettability (n=30) and biofilm adhesion (n=9) tests. Three roughness measurements were taken by laser confocal microscopy and a mean value was calculated. Wettability was evaluated by the contact angle of sessile drop method, considering the mean of the three evaluations per specimen. In parallel, microorganism adhesion to resin surfaces was evaluated using a multispecies biofilm model. Microbial load was evaluated by determining the number of Colony Forming Units (CFU/mL) and by scanning electron microscopy (SEM). Data were subjected to the Wald test in a generalized linear model with multiple comparisons and Bonferroni adjustment, as well as two-way ANOVA (&#x3b1;=5%).<br><br>RESULTS: The roughness of the conventional base resin (0.01&#xb1;0.04) was lower than that of the conventional tooth (0.14&#xb1;0.04) (p=0.023) and 3D-printed base (0.18&#xb1;0.08) (p<0.001). For wettability, conventional resin (84.20&#xb1;5.57) showed a higher contact angle than the 3D-printed resin (60.58&#xb1;6.18) (p<0.001). Higher microbial loads of S. mutans (p=0.023) and S. aureus (p=0.010) were observed on the surface of the conventional resin (S. mutans: 5.48&#xb1;1.55; S. aureus: 7.01&#xb1;0.57) compared to the 3D-printed resin (S. mutans: 4.11&#xb1;1.96; S. aureus: 6.42&#xb1;0.78). The adhesion of C. albicans was not affected by surface characteristics. The conventional base resin showed less roughness than the conventional dental resin and the printed base resin.<br><br>CONCLUSION: The 3D-printed resins for base and tooth showed less hydrophobicity and less adhesion of S. mutans and S. aureus than conventional resins.}, }
@article {pmid38655044, year = {2024}, author = {Ahrari, F and Nazifi, M and Mazhari, F and Ghazvini, K and Menbari, S and Fekrazad, R and Babaei, K and Banihashemrad, A}, title = {Photoinactivation Effects of Curcumin, Nano-curcumin, and Erythrosine on Planktonic and Biofilm Cultures of Streptococcus mutans.}, journal = {Journal of lasers in medical sciences}, volume = {15}, number = {}, pages = {e7}, pmid = {38655044}, issn = {2008-9783}, abstract = {Introduction: This in vitro study was conducted to assess the phototoxic effects of curcumin, nano-curcumin, and erythrosine on the viability of Streptococcus mutans (S. mutans) in suspension and biofilm forms. Methods: Various concentrations of curcumin (1.5 g/L, 3 g/L), nano-curcumin (3 g/L), and erythrosine (100 μM/L, 250 μM/L) were examined for their impact on planktonic and biofilm cultures of S. mutans, either individually or in conjunction with light irradiation (photodynamic therapy or PDT). A blue light-emitting diode (LED) with a central wavelength of 450 nm served as the light source. The results were compared to 0.12% chlorhexidine digluconate (CHX) as the positive control, and a solution containing neither a photosensitizer (PS) nor a light source as the negative control group. The dependent variable was the number of viable microorganisms per experiment (CFU/mL). Results: Antimicrobial PDT caused a significant reduction in the viability of S. mutans in both planktonic and biofilm forms, compared to the negative control group (P<0.05). The highest cell killing was observed in PDT groups with curcumin 3 g/L or erythrosine 250 μmol/L, although the difference with PDT groups using curcumin 1.5 g/L or erythrosine 100 μmol/L was not significant (P>0.05). Antimicrobial treatments were more effective against planktonic S. mutans than the biofilm form. Conclusion: PDT with either curcumin 1.5 g/L or erythrosine 100 μmol/L may be suggested as an alternative to CHX to inactivate the bacteria in dental plaque or deep cavities. Nano-curcumin, at the selected concentration, exhibited lower efficacy in killing S. mutans compared to Curcumin or erythrosine.}, }
@article {pmid38654614, year = {2024}, author = {Li, Z and Lu, S and Liu, W and Chen, Z and Huang, Y and Li, X and Gong, J and Chen, X}, title = {Customized Lanthanide Nanobiohybrids for Noninvasive Precise Phototheranostics of Pulmonary Biofilm Infection.}, journal = {ACS nano}, volume = {18}, number = {18}, pages = {11837-11848}, doi = {10.1021/acsnano.4c00777}, pmid = {38654614}, issn = {1936-086X}, mesh = {*Biofilms/drug effects ; Animals ; Mice ; *Theranostic Nanomedicine ; *Pseudomonas aeruginosa/drug effects ; *Lanthanoid Series Elements/chemistry/pharmacology ; Pseudomonas Infections/drug therapy/microbiology ; Anti-Bacterial Agents/pharmacology/chemistry ; Humans ; Photothermal Therapy ; Mice, Inbred BALB C ; }, abstract = {A noninvasive strategy for in situ diagnosis and precise treatment of bacterial biofilm infections is highly anticipated but still a great challenge. Currently, no in vivo biofilm-targeted theranostic agent is available. Herein, we fabricated intelligent theranostic alginate lyase (Aly)-NaNdF4 nanohybrids with a 220 nm sunflower-like structure (NaNdF4@DMS-Aly) through an enrichment-encapsulating strategy, which exhibited excellent photothermal conversion efficiency and the second near-infrared (NIR-II) luminescence. Benefiting from the site-specific targeting and biofilm-responsive Aly release from NaNdF4@DMS-Aly, we not only enabled noninvasive diagnosis but also realized Aly-photothermal synergistic therapy and real-time evaluation of therapeutic effect in mice models with Pseudomonas aeruginosa biofilm-induced pulmonary infection. Furthermore, such nanobiohybrids with a sheddable siliceous shell are capable of delaying the NaNdF4 dissolution and biodegradation upon accomplishing the therapy, which is highly beneficial for the biosafety of theranostic agents.}, }
@article {pmid38652947, year = {2024}, author = {Pokhrel, D and Thames, HT and Fugate, H and Dinh, T and Schilling, W and White, S and Ramachandran, R and Sukumaran, AT and Zhang, L}, title = {Increase in temperature facilitates Campylobacter jejuni biofilm formation under both aerobic and microaerobic incubation.}, journal = {Poultry science}, volume = {103}, number = {6}, pages = {103753}, pmid = {38652947}, issn = {1525-3171}, mesh = {*Biofilms ; *Campylobacter jejuni/physiology ; *Stainless Steel ; *Temperature ; Aerobiosis ; Animals ; Food Microbiology ; }, abstract = {The formation of Campylobacter jeuni biofilms on processing surfaces is a significant concern in poultry processing, contributing to food safety risks. This study focused on assessing the biofilm forming capabilities of 12 field isolates of C. jejuni of different aerotolerance categories on stainless steel surfaces, a prevalent material in poultry processing environments. Working cultures of each isolate were prepared to approximately 6 log CFU/mL and incubated on stainless steel coupons under microaerobic or aerobic conditions at room temperature or 42°C for 72 h. Biofilm attached cells were enumerated using direct plating and biofilm density was measured using a crystal violet assay by measuring the optical density (OD600) a. Data analysis was conducted using the PROC GLIMMIX procedure in SAS 9.4 with a significance level of 0.05. The study revealed a notable interaction between aerotolerance categories and temperature (P < 0.039) impacting the number of biofilms attached C. jejuni cells on stainless steel coupons. All isolates had significantly higher counts when incubated at 42°C compared to room temperature, regardless of oxygen level (P < 0.001). Furthermore, stronger biofilm density was observed at 42°C compared to room temperature, regardless of oxygen level. These findings underscore the influence of temperature on the biofilm forming ability of C. jejuni. The ability of these field isolates to form biofilms under various environmental conditions suggests a heightened potential for surface colonization and increased infection risk in poultry processing facilities.}, }
@article {pmid38652228, year = {2024}, author = {Cao, CY and Hou, ZJ and Ding, MZ and Gao, GR and Qiao, B and Wei, SY and Cheng, JS}, title = {Integrated Biofilm Modification and Transcriptional Analysis for Improving Fengycin Production in Bacillus amyloliquefaciens.}, journal = {Probiotics and antimicrobial proteins}, volume = {}, number = {}, pages = {}, pmid = {38652228}, issn = {1867-1314}, support = {2018YFA0902200//National Key R&amp;D Program of China/ ; 2018YFA0902200//National Key R&amp;D Program of China/ ; 2018YFA0902200//National Key R&amp;D Program of China/ ; 21878224//National Natural Science Foundation of China/ ; }, abstract = {Although fengycin exhibits broad-spectrum antifungal properties, its application is hindered due to its low biosynthesis level and the co-existence of iturin A and surfactin in Bacillus amyloliquefaciens HM618, a probiotic strain. In this study, transcriptome analysis and gene editing were used to explore the potential mechanisms regulating fengycin production in B. amyloliquefaciens. The fengycin level of B. amyloliquefacien HM-3 (∆itu-ΔsrfAA) was 88.41 mg/L after simultaneously inhibiting the biosyntheses of iturin A and surfactin. The knockout of gene eps associated with biofilm formation significantly increased the fengycin level of the strain HM618, whereas the fengycin level decreased 32.05% after knocking out sinI, a regulator of biofilm formation. Transcriptome analysis revealed that the differentially expressed genes, involved in pathways of amino acid and fatty acid syntheses, were significantly down-regulated in the recombinant strains, which is likely associated with a decrease of fengycin production. The knockout of gene comQXPA and subsequent transcriptome analysis revealed that the ComQXPA quorum sensing system played a positive regulatory role in fengycin production. Through targeted genetic modifications and fermentation optimization, the fengycin production of the engineered strain HM-12 (∆itu-ΔsrfAA-ΔyvbJ) in a 5-L fermenter reached 1.172 g/L, a 12.26-fold increase compared to the fengycin level in the strain HM-3 (∆itu-ΔsrfAA) in the Erlenmeyer flask. Taken together, these results reveal the underlying metabolic mechanisms associated with fengycin synthesis and provide a potential strategy for improving fengycin production in B. amyloliquefaciens.}, }
@article {pmid38651875, year = {2024}, author = {Park, K-H and Kim, D and Jung, M and Kim, DY and Lee, Y-M and Lee, MS and Hong, K-W and Bae, I-G and Hong, SI and Cho, O-H}, title = {Effects of sub-inhibitory concentrations of nafcillin, vancomycin, ciprofloxacin, and rifampin on biofilm formation of clinical methicillin-resistant Staphylococcus aureus.}, journal = {Microbiology spectrum}, volume = {12}, number = {6}, pages = {e0341223}, pmid = {38651875}, issn = {2165-0497}, support = {NRF-2018R1D1A1B07040831//Ministry of Science and ICT, South Korea (MSIT)/ ; RS-2023-00246999//Ministry of Science and ICT, South Korea (MSIT)/ ; HI23C0299//Ministry of Health and Welfare (MOHW)/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Methicillin-Resistant Staphylococcus aureus/drug effects/genetics ; *Ciprofloxacin/pharmacology ; *Microbial Sensitivity Tests ; *Vancomycin/pharmacology ; *Rifampin/pharmacology ; *Nafcillin/pharmacology ; *Anti-Bacterial Agents/pharmacology ; Humans ; *Staphylococcal Infections/microbiology/drug therapy ; Bacterial Proteins/genetics/metabolism ; }, abstract = {UNLABELLED: Methicillin-resistant Staphylococcus aureus (MRSA) infections are often difficult to treat because of their biofilm-forming ability and antimicrobial resistance. We investigated the effects of sub-minimal inhibitory concentrations (MICs) of antibiotics on MRSA biofilm formation. Clinical MRSA isolates were grown with sub-MICs (1/256-1/2 × MICs) of nafcillin, vancomycin, ciprofloxacin, and rifampin. The biofilm biomass was measured using crystal violet staining. Of the 107 MRSA isolates tested, 63 (58.9%) belonged to sequence type 5 (ST5), and 44 (41.1%) belonged to ST72. The MIC50/MIC90 values of nafcillin, vancomycin, ciprofloxacin, and rifampin were 256/512, 1/2, 64/512, and 0.008/0.03 mg/L, respectively. The sub-MICs of nafcillin, vancomycin, ciprofloxacin, and rifampin promoted biofilm formation in 75 (70.1%), 49 (45.8%), 89 (83.2%), and 89 (83.2%) isolates, respectively. At sub-MICs of nafcillin, the factors associated with strong biofilm induction were the ST5 strain (P = 0.001) and agr dysfunction (P = 0.005). For the sub-MICs of ciprofloxacin, the associated factors were the ST5 strain (P = 0.002), staphylococcal protein A type t002 strain (P < 0.001), and ciprofloxacin resistance (P < 0.001). Among the sub-MICs of rifampin, only ST5 was associated with strong biofilm induction (P = 0.006). Because the sub-MICs of rifampin were much lower than clinically relevant concentrations, we further tested the capability of biofilm induction in 0.03[Formula: see text]32 mg/L of rifampin. At these concentrations, rifampin-induced biofilm formation was rare in rifampin-susceptible MRSA [1.0% (1 of 100)] but common in rifampin-resistant MRSA [71.4% (5 of 7), P < 0.001]. Induction of biofilm biomass at sub-MICs of antibiotics is common in clinical MRSA isolates and is differentially affected by the MRSA strain and antibiotic class.<br><br>IMPORTANCE: Bacteria can be exposed to sub-MICs of antibiotics at the beginning and end of a dosing regimen, between doses, or during low-dose therapies. Growing evidence suggests that sub-MICs of antimicrobials can stimulate MRSA biofilm formation and alter the composition of the biofilm matrix. Pevious studies have found that sub-MICs of oxacillin, methicillin, and amoxicillin promote biofilm formation in some community-acquired MRSA (CA-MRSA). We evaluated biofilm induction by sub-MICs of four different classes of antibiotics in 44 CA-MRSA and 63 healthcare-associated MRSA (HA-MRSA) strains. Our study indicated that sub-MICs of nafcillin, vancomycin, ciprofloxacin, and rifampin frequently promote biofilm induction in clinical MRSA isolates. Strong biofilm induction in sub-MICs of nafcillin, ciprofloxacin, and rifampin was more frequent in HA-MRSA than in CA-MRSA. Antibiotic-induced biofilm formation depends on the antibiotic class, MRSA strain, and antibiotic resistance. Our results emphasize the importance of maintaining effective bactericidal concentrations of antibiotics to treat biofilm-related infections.}, }
@article {pmid38651823, year = {2024}, author = {Galvez-Llompart, M and Hierrezuelo, J and Blasco, M and Zanni, R and Galvez, J and de Vicente, A and Pérez-García, A and Romero, D}, title = {Targeting bacterial growth in biofilm conditions: rational design of novel inhibitors to mitigate clinical and food contamination using QSAR.}, journal = {Journal of enzyme inhibition and medicinal chemistry}, volume = {39}, number = {1}, pages = {2330907}, pmid = {38651823}, issn = {1475-6374}, mesh = {*Biofilms/drug effects ; *Quantitative Structure-Activity Relationship ; *Anti-Bacterial Agents/pharmacology/chemistry/chemical synthesis ; *Microbial Sensitivity Tests ; *Drug Design ; Molecular Structure ; Humans ; Food Contamination/prevention &amp; control ; Dose-Response Relationship, Drug ; }, abstract = {Antimicrobial resistance (AMR) is a pressing global issue exacerbated by the abuse of antibiotics and the formation of bacterial biofilms, which cause up to 80% of human bacterial infections. This study presents a computational strategy to address AMR by developing three novel quantitative structure-activity relationship (QSAR) models based on molecular topology to identify potential anti-biofilm and antibacterial agents. The models aim to determine the chemo-topological pattern of Gram (+) antibacterial, Gram (-) antibacterial, and biofilm formation inhibition activity. The models were applied to the virtual screening of a commercial chemical database, resulting in the selection of 58 compounds. Subsequent in vitro assays showed that three of these compounds exhibited the most promising antibacterial activity, with potential applications in enhancing food and medical device safety.}, }
@article {pmid38650753, year = {2024}, author = {Wen, Z and Chen, Y and Liu, T and Han, J and Jiang, Y and Zhang, K}, title = {Predicting Antibiotic Tolerance in hvKP and cKP Respiratory Infections Through Biofilm Formation Analysis and Its Resistance Implications.}, journal = {Infection and drug resistance}, volume = {17}, number = {}, pages = {1529-1537}, pmid = {38650753}, issn = {1178-6973}, abstract = {INTRODUCTION: Respiratory infections are a major global health concern, with Klebsiella pneumoniae standing out due to its evolving antibiotic resistance. This study compares the resistance profiles of hypervirulent Klebsiella pneumoniae (hvKP) and classical Klebsiella pneumoniae (cKP), aiming to shed light on their clinical implications.<br><br>METHODS: We analyzed 86 cases, comprising 42 hvKP and 44 cKP strains, using comprehensive antimicrobial susceptibility testing and clinical data evaluation to assess antibiotic tolerance and resistance mechanisms.<br><br>RESULTS: Our findings reveal distinct resistance patterns between hvKP and cKP, highlighting the role of chromosomal mutations and plasmid-mediated gene transfer in conferring antibiotic resistance. Notably, hvKP strains exhibited unique resistance trends, including the production of extended-spectrum &#x3b2;-lactamases (ESBLs) and carbapenemases, differing from those of cKP.<br><br>DISCUSSION: This research underscores the importance of continuous surveillance and the development of targeted therapies against antibiotic-resistant Klebsiella pneumoniae. It emphasizes the critical need for judicious antibiotic use and novel therapeutic approaches to combat respiratory infections caused by these increasingly resistant pathogens.}, }
@article {pmid38650397, year = {2024}, author = {Kovács, F and Balla, N and Bozó, A and Harmath, A and Jakab, &#xc1; and Tóth, Z and Nagy, F and Majoros, L and Kovács, R}, title = {Epidemiology, clinical characteristics, outcome and biofilm forming properties in candidaemia: A single-centre retrospective 4-year analysis from Hungary.}, journal = {Mycoses}, volume = {67}, number = {4}, pages = {e13727}, doi = {10.1111/myc.13727}, pmid = {38650397}, issn = {1439-0507}, support = {UNKP-23-5-DE-480//New National Excellence Program of the Ministry for Innovation and Technology from the Source of the National Research, Development and Innovation Fund/ ; NKFIH FK138462//Hungarian National Research, Development and Innovation Office/ ; BO/00127/21/8//Janos Bolyai Research Scholarship of the Hungarian Academy of Sciences/ ; }, mesh = {Humans ; *Candidemia/microbiology/epidemiology/mortality/drug therapy ; *Biofilms/growth &amp; development/drug effects ; Retrospective Studies ; Female ; Male ; Hungary/epidemiology ; *Antifungal Agents/therapeutic use/pharmacology ; *Candida/drug effects/isolation &amp; purification/classification/physiology ; Middle Aged ; Aged ; Microbial Sensitivity Tests ; Adult ; Risk Factors ; Intensive Care Units/statistics &amp; numerical data ; Aged, 80 and over ; Fluconazole/therapeutic use/pharmacology ; }, abstract = {BACKGROUND: Candidaemia is a life-threatening disease that is associated with high mortality, especially in intensive care units (ICUs). The number of comprehensive studies dealing with the epidemiologic characteristics of biofilm-related properties is limited.<br><br>OBJECTIVE: This study evaluated the clinical characteristics of candidaemia, to assess the biofilm-forming properties of isolates, and to identify the risk factors of mortality.<br><br>PATIENTS AND METHODS: A total of 149 candidaemia episodes from the University of Debrecen, Clinical Centre, between January 2020 and December 2023 were investigated retrospectively. The susceptibility of Candida isolates to fluconazole, amphotericin B, anidulafungin, caspofungin, and micafungin was evaluated and compared to the susceptibility of 1-day-old biofilms. Multivariate logistic regression analysis was applied to identify the independent predictors of 30-day mortality rate.<br><br>RESULTS: The most common Candida species was Candida albicans (41%), followed by C. parapsilosis (20%), C. glabrata (14%), C. tropicalis (13%), rare Candida species (7%), and C. krusei (5%). Sixty-six percent of Candida isolates were biofilm formers and 44% had high metabolic activity. The 30-day mortality rate was 52%, which was higher in ICUs (65%). The logistic regression analysis revealed several factors significantly influencing mortality including ICU admission (odds ratio [OR] 2.99, 95% confidence interval [CI] 1.17-8.04, p&#x2009;=&#x2009;0.025), fluconazole treatment (OR 4.12, 95% CI 1.62-11.42, p&#x2009;=&#x2009;.004), and pneumonia (OR 0.261, 95% CI 0.1-0.67, p&#x2009;=&#x2009;.006).<br><br>CONCLUSIONS: This comprehensive analysis supports the better characterisation of candidaemia in healthcare settings, which ultimately may reduce mortality among patients.}, }
@article {pmid38649897, year = {2024}, author = {Chan, YL and Chee, CF and Tang, SN and Tay, ST}, title = {Unveilling genetic profiles and correlations of biofilm-associated genes, quorum sensing, and antibiotic resistance in Staphylococcus aureus isolated from a Malaysian Teaching Hospital.}, journal = {European journal of medical research}, volume = {29}, number = {1}, pages = {246}, pmid = {38649897}, issn = {2047-783X}, support = {IIRG003C-19FNW//Impact Oriented Interdisciplinary Grant/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Quorum Sensing/genetics/drug effects ; Malaysia ; Humans ; *Methicillin-Resistant Staphylococcus aureus/genetics/drug effects/isolation &amp; purification ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology ; *Hospitals, Teaching ; *Staphylococcus aureus/genetics/drug effects/isolation &amp; purification ; Staphylococcal Infections/microbiology/drug therapy ; Bacterial Proteins/genetics ; }, abstract = {BACKGROUND: Staphylococcus aureus is a notorious multidrug resistant pathogen prevalent in healthcare facilities worldwide. Unveiling the mechanisms underlying biofilm formation, quorum sensing and antibiotic resistance can help in developing more effective therapy for S. aureus infection. There is a scarcity of literature addressing the genetic profiles and correlations of biofilm-associated genes, quorum sensing, and antibiotic resistance among S. aureus isolates from Malaysia.<br><br>METHODS: Biofilm and slime production of 68 methicillin-susceptible S. aureus (MSSA) and 54 methicillin-resistant (MRSA) isolates were determined using a a plate-based crystal violet assay and Congo Red agar method, respectively. The minimum inhibitory concentration values against 14 antibiotics were determined using VITEK&#xae; AST-GP67 cards and interpreted according to CLSI-M100 guidelines. Genetic profiling of 11 S. aureus biofilm-associated genes and agr/sar quorum sensing genes was performed using single or multiplex polymerase chain reaction (PCR) assays.<br><br>RESULTS: In this study, 75.9% (n&#x2009;=&#x2009;41) of MRSA and 83.8% (n&#x2009;=&#x2009;57) of MSSA isolates showed strong biofilm-forming capabilities. Intermediate slime production was detected in approximately 70% of the isolates. Compared to MSSA, significantly higher resistance of clindamycin, erythromycin, and fluoroquinolones was noted among the MRSA isolates. The presence of intracellular adhesion A (icaA) gene was detected in all S. aureus isolates. All MSSA isolates harbored the laminin-binding protein (eno) gene, while all MRSA isolates harbored intracellular adhesion D (icaD), clumping factors A and B (clfA and clfB) genes. The presence of agrI and elastin-binding protein (ebpS) genes was significantly associated with biofilm production in MSSA and MRSA isolates, respectively. In addition, agrI gene was also significantly correlated with oxacillin, cefoxitin, and fluoroquinolone resistance.<br><br>CONCLUSIONS: The high prevalence of biofilm and slime production among MSSA and MRSA isolates correlates well with the detection of a high prevalence of biofilm-associated genes and agr quorum sensing system. A significant association of agrI gene was found with cefoxitin, oxacillin, and fluoroquinolone resistance. A more focused approach targeting biofilm-associated and quorum sensing genes is important in developing new surveillance and treatment strategies against S. aureus biofilm infection.}, }
@article {pmid38649100, year = {2024}, author = {Gulati, M and Thomas, JM and Ennis, CL and Hernday, AD and Rawat, M and Nobile, CJ}, title = {The bacillithiol pathway is required for biofilm formation in Staphylococcus aureus.}, journal = {Microbial pathogenesis}, volume = {191}, number = {}, pages = {106657}, doi = {10.1016/j.micpath.2024.106657}, pmid = {38649100}, issn = {1096-1208}, mesh = {*Biofilms/growth &amp; development ; *Staphylococcus aureus/physiology/genetics ; *Glucosamine/analogs &amp; derivatives/metabolism ; *Cysteine/analogs &amp; derivatives/metabolism ; *Nitric Oxide/metabolism ; Sodium Nitrite/pharmacology ; Bacterial Proteins/metabolism/genetics ; Mycobacterium smegmatis/genetics/physiology/metabolism ; Mutation ; Humans ; Oxidoreductases/metabolism/genetics ; Sulfhydryl Compounds/metabolism ; Oxidative Stress ; }, abstract = {Staphylococcus aureus is a major human pathogen that can cause infections that range from superficial skin and mucosal infections to life threatening disseminated infections. S. aureus can attach to medical devices and host tissues and form biofilms that allow the bacteria to evade the host immune system and provide protection from antimicrobial agents. To counter host-generated oxidative and nitrosative stress mechanisms that are part of the normal host responses to invading pathogens, S. aureus utilizes low molecular weight (LMW) thiols, such as bacillithiol (BSH). Additionally, S. aureus synthesizes its own nitric oxide (NO), which combined with its downstream metabolites may also protect the bacteria against specific host responses. We have previously shown that LMW thiols are required for biofilm formation in Mycobacterium smegmatis and Pseudomonas aeruginosa. Here, we show that the S. aureus bshC mutant strain, which is defective in the last step of the BSH pathway and lacks BSH, is impaired in biofilm formation. We also identify a possible S-nitrosobacillithiol reductase (BSNOR), similar in sequence to an S-nitrosomycothiol reductase found in M. smegmatis and show that the putative S. aureus bsnoR mutant strain has reduced levels of BSH and decreased biofilm formation. Our studies also show that NO plays an important role in biofilm formation and that acidified sodium nitrite severely reduces biofilm thickness. These studies provide insight into the roles of oxidative and nitrosative stress mechanisms on biofilm formation and indicate that BSH and NO are key players in normal biofilm formation in S. aureus.}, }
@article {pmid38647810, year = {2024}, author = {Zhang, CL and Wang, C and Dong, YS and Sun, YQ and Xiu, ZL}, title = {Dynamic immobilization of bacterial cells on biofilm in a polyester nonwoven chemostat.}, journal = {Bioresources and bioprocessing}, volume = {11}, number = {1}, pages = {17}, pmid = {38647810}, issn = {2197-4365}, support = {No. 2022YFA0911802//National Key R&amp;D Program of China/ ; 2022YFA0911804//National Key R&amp;D Program of China/ ; }, abstract = {Cell immobilization plays an important role in biocatalysis for high-value products. It is necessary to maintain the viability of immobilized cells for bioconversion using viable cells as biocatalysts. In this study, a novel polyester nonwoven chemostat was designed for cell immobilization to investigate biofilm formation and the dynamic balance between adsorption and desorption of cells on polyester nonwoven. The polyester nonwoven was suitable for cell immobilization, and the cell numbers on the polyester nonwoven can reach 6.5 ± 0.38 log CFU/mL. After adding the polyester nonwoven to the chemostat, the fluctuation phenomenon of free bacterial cells occurred. The reason for this phenomenon was the balance between adsorption and desorption of bacterial cells on the polyester nonwoven. Bacterial cells could adhere to the surface of polyester nonwoven via secreting extracellular polymeric substances (EPS) to form biofilms. As the maturation of biofilms, some dead cells inside the biofilms can cause the detachment of biofilms. This process of continuous adsorption and desorption of cells can ensure that the polyester nonwoven chemostat has lasting biological activity.}, }
@article {pmid38647288, year = {2024}, author = {Waegenaar, F and García-Timermans, C and Van Landuyt, J and De Gusseme, B and Boon, N}, title = {Impact of operational conditions on drinking water biofilm dynamics and coliform invasion potential.}, journal = {Applied and environmental microbiology}, volume = {90}, number = {5}, pages = {e0004224}, pmid = {38647288}, issn = {1098-5336}, support = {1S02022N//Fonds Wetenschappelijk Onderzoek (FWO)/ ; S006221N//Fonds Wetenschappelijk Onderzoek (FWO)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Drinking Water/microbiology ; *Enterobacteriaceae/physiology/isolation &amp; purification ; RNA, Ribosomal, 16S/genetics ; Water Quality ; Water Purification ; Water Microbiology ; Water Supply ; }, abstract = {UNLABELLED: Biofilms within drinking water distribution systems serve as a habitat for drinking water microorganisms. However, biofilms can negatively impact drinking water quality by causing water discoloration and deterioration and can be a reservoir for unwanted microorganisms. In this study, we investigated whether indicator organisms for drinking water quality, such as coliforms, can settle in mature drinking water biofilms. Therefore, a biofilm monitor consisting of glass rings was used to grow and sample drinking water biofilms. Two mature drinking water biofilms were characterized by flow cytometry, ATP measurements, confocal laser scanning microscopy, and 16S rRNA sequencing. Biofilms developed under treated chlorinated surface water supply exhibited lower cell densities in comparison with biofilms resulting from treated groundwater. Overall, the phenotypic as well as the genotypic characteristics were significantly different between both biofilms. In addition, the response of the biofilm microbiome and possible biofilm detachment after minor water quality changes were investigated. Limited changes in pH and free chlorine addition, to simulate operational changes that are relevant for practice, were evaluated. It was shown that both biofilms remained resilient. Finally, mature biofilms were prone to invasion of the coliform, Serratia fonticola. After spiking low concentrations (i.e., ±100 cells/100 mL) of the coliform to the corresponding bulk water samples, the coliforms were able to attach and get established within the mature biofilms. These outcomes emphasize the need for continued research on biofilm detachment and its implications for water contamination in distribution networks.<br><br>IMPORTANCE: The revelation that even low concentrations of coliforms can infiltrate into mature drinking water biofilms highlights a potential public health concern. Nowadays, the measurement of coliform bacteria is used as an indicator for fecal contamination and to control the effectiveness of disinfection processes and the cleanliness and integrity of distribution systems. In Flanders (Belgium), 533 out of 18,840 measurements exceeded the established norm for the coliform indicator parameter in 2021; however, the source of microbial contamination is mostly unknown. Here, we showed that mature biofilms, are susceptible to invasion of Serratia fonticola. These findings emphasize the importance of understanding and managing biofilms in drinking water distribution systems, not only for their potential to influence water quality, but also for their role in harboring and potentially disseminating pathogens. Further research into biofilm detachment, long-term responses to operational changes, and pathogen persistence within biofilms is crucial to inform strategies for safeguarding drinking water quality.}, }
@article {pmid38646063, year = {2024}, author = {Toma, TT and Wang, Y and Gahlmann, A and Acton, ST}, title = {DeepSeeded: Volumetric Segmentation of Dense Cell Populations with a Cascade of Deep Neural Networks in Bacterial Biofilm Applications.}, journal = {Expert systems with applications}, volume = {238}, number = {Pt D}, pages = {}, pmid = {38646063}, issn = {0957-4174}, support = {R01 GM139002/GM/NIGMS NIH HHS/United States ; }, abstract = {Accurate and automatic segmentation of individual cell instances in microscopy images is a vital step for quantifying the cellular attributes, which can subsequently lead to new discoveries in biomedical research. In recent years, data-driven deep learning techniques have shown promising results in this task. Despite the success of these techniques, many fail to accurately segment cells in microscopy images with high cell density and low signal-to-noise ratio. In this paper, we propose a novel 3D cell segmentation approach DeepSeeded, a cascaded deep learning architecture that estimates seeds for a classical seeded watershed segmentation. The cascaded architecture enhances the cell interior and border information using Euclidean distance transforms and detects the cell seeds by performing voxel-wise classification. The data-driven seed estimation process proposed here allows segmenting touching cell instances from a dense, intensity-inhomogeneous microscopy image volume. We demonstrate the performance of the proposed method in segmenting 3D microscopy images of a particularly dense cell population called bacterial biofilms. Experimental results on synthetic and two real biofilm datasets suggest that the proposed method leads to superior segmentation results when compared to state-of-the-art deep learning methods and a classical method.}, }
@article {pmid38644015, year = {2024}, author = {Zhou, M and Han, Y and Zhuo, Y and Yu, F and Hu, G and Peng, D}, title = {Effect of initial ammonium concentration on a one-stage partial nitrification/anammox biofilm system: Nitrogen removal performance and the microbial community.}, journal = {Journal of environmental sciences (China)}, volume = {143}, number = {}, pages = {176-188}, doi = {10.1016/j.jes.2023.07.026}, pmid = {38644015}, issn = {1001-0742}, mesh = {*Biofilms ; *Nitrification ; *Nitrogen ; *Ammonium Compounds/metabolism ; *Bioreactors/microbiology ; Waste Disposal, Fluid/methods ; Bacteria/metabolism ; Microbiota ; }, abstract = {One-stage partial nitrification coupled with anammox (PN/A) technology effectively reduces the energy consumption of a biological nitrogen removal system. Inhibiting nitrite-oxidizing bacteria (NOB) is essential for this technology to maintain efficient nitrogen removal performance. Initial ammonium concentration (IAC) affects the degree of inhibited NOB. In this study, the effect of the IAC on a PN/A biofilm was investigated in a moving bed biofilm reactor. The results showed that nitrogen removal efficiency decreased from 82.49% ± 1.90% to 64.57% ± 3.96% after the IAC was reduced from 60 to 20 mg N/L, while the nitrate production ratio increased from 13.87% ± 0.90% to 26.50% ± 3.76%. NOB activity increased to 1,133.86 mg N/m[2]/day after the IAC decreased, approximately 4-fold, indicating that the IAC plays an important inhibitory role in NOB. The rate-limiting step in the mature biofilm of the PN/A system is the nitritation process and is not shifted by the IAC. The analysis of the microbial community structure in the biofilm indicates that the IAC was the dominant factor in changes in community structure. Ca. Brocadia and Ca. Jettenia were the main anammox bacteria, and Nitrosomonas and Nitrospira were the main AOB and NOB, respectively. IAC did not affect the difference in growth between Ca. Brocadia and Ca. Jettenia. Thus, modulating the IAC promoted the PN/A process with efficient nitrogen removal performance at medium to low ammonium concentrations.}, }
@article {pmid38643952, year = {2024}, author = {Zhou, W and Hao, J and Guo, Y and Zhao, C and Zhang, M and Zhang, S and Han, F}, title = {Revealing bioresponses of biofilm and flocs to salinity gradient in halophilic biofilm reactor.}, journal = {Bioresource technology}, volume = {401}, number = {}, pages = {130727}, doi = {10.1016/j.biortech.2024.130727}, pmid = {38643952}, issn = {1873-2976}, mesh = {*Biofilms ; *Salinity ; *Bioreactors/microbiology ; Nitrogen ; Bacteria/metabolism/genetics ; }, abstract = {Understanding the different biological responses to salinity gradient between coexisting biofilm and flocs is crucial for regulating the ecological function of biofilm system. This study investigated performance, dynamics, and community assembly of biofilm system under 3 %-7% salinity gradient. The removal efficiency of NH4[+]-N remained stable and exceeded 93 % at 3 %-6% salinity, but decreased to below 80 % at 7 % salinity. The elevated salinity promoted the synthesis of extracellular polymer substrates, inhibited microbial respiration, and significantly regulated the microbial community structure. Compared to flocs, biofilm exhibited greater species diversity and richer Nitrosomonas. It was found diffusion limitations dominated the microbial community assembly under the salinity gradient. And microbial network revealed positive interactions predominated the microbial relationships, designating norank Spirochaetaceae, unclassified Micrococcales, Corynebacterium, and Pusillimonas as keystone species. Moreover, distinct salinity preferences in nitrogen transformation-related genes were observed. This study can improve the understanding to the regulation of biofilm systems to salt stresses.}, }
@article {pmid38643850, year = {2024}, author = {Tabassum, N and Jeong, GJ and Jo, DM and Khan, F and Kim, YM}, title = {Attenuation of biofilm and virulence factors of Pseudomonas aeruginosa by tetramethylpyrazine-gold nanoparticles.}, journal = {Microbial pathogenesis}, volume = {191}, number = {}, pages = {106658}, doi = {10.1016/j.micpath.2024.106658}, pmid = {38643850}, issn = {1096-1208}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Gold/chemistry/pharmacology ; *Pseudomonas aeruginosa/drug effects/genetics ; *Virulence Factors/genetics ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Pyrazines/pharmacology ; *Microbial Sensitivity Tests ; *Metal Nanoparticles/chemistry ; Staphylococcus aureus/drug effects/genetics ; Escherichia coli/drug effects/genetics ; Klebsiella pneumoniae/drug effects ; Streptococcus mutans/drug effects/genetics ; Listeria monocytogenes/drug effects/genetics ; }, abstract = {Pseudomonas aeruginosa is often identified as the causative agent in nosocomial infections. Their adapted resistance makes them strong towards antimicrobial treatments. They protect and empower their survival behind strong biofilm architecture that works as their armor toward antimicrobial therapy. Additionally, P. aeruginosa generates virulence factors, contributing to chronic infection and recalcitrant phenotypic characteristics. The current study utilizes the benevolence of nanotechnology to develop an alternate technique to control the spreading of P. aeruginosa by limiting its biofilm and virulence development. This study used a natural compound, tetramethylpyrazine, to generate gold nanoparticles. Tetramethylpyrazine-gold nanoparticles (Tet-AuNPs) were presented in spherical shapes, with an average size of 168 ± 52.49 nm and a zeta potential of -12.22 ± 2.06 mV. The minimum inhibition concentration (MIC) of Tet-AuNPs that proved more than 90 % effective in inhibiting P. aeruginosa was 256 μg/mL. Additionally, it also shows antibacterial activities against Staphylococcus aureus (MIC, 256 μg/mL), Streptococcus mutans (MIC, 128 μg/mL), Klebsiella pneumoniae (MIC, 128 μg/mL), Listeria monocytogenes (MIC, 256 μg/mL), and Escherichia coli (MIC, 256 μg/mL). The sub-MIC values of Tet-AuNPs significantly inhibited the early-stage biofilm formation of P. aeruginosa. Moreover, this concentration strongly affected hemolysis, protease activity, and different forms of motilities in P. aeruginosa. Additionally, Tet-AuNPs destroyed the well-established mature biofilm of P. aeruginosa. The expression of genes linked with the biofilm formation and virulence in P. aeruginosa treated with sub-MIC doses of Tet-AuNPs was shown to be significantly suppressed. Gene expression studies support biofilm- and virulence-suppressing effects of Tet-AuNPs at the phenotypic level.}, }
@article {pmid38643226, year = {2024}, author = {Ahmed, GE and Elshahid, ZA and El-Sawy, ER and Abdel-Aziz, MS and Abdel-Aziem, A}, title = {Synthesis, biofilm formation inhibitory, and inflammation inhibitory activities of new coumarin derivatives.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {9106}, pmid = {38643226}, issn = {2045-2322}, mesh = {Humans ; *Anti-Bacterial Agents/pharmacology/chemistry ; Staphylococcus aureus ; *Methicillin-Resistant Staphylococcus aureus ; Escherichia coli ; Gram-Positive Bacteria ; Gram-Negative Bacteria ; Coumarins/pharmacology ; Inflammation/drug therapy ; Biofilms ; Anti-Inflammatory Agents/pharmacology ; Microbial Sensitivity Tests ; }, abstract = {Coumarins are heterocycles of great interest in the development of valuable active structures in chemistry and biological domains. The ability of coumarins to inhibit biofilm formation of Gram positive bacterium (Staphylococcus aureus), Gram negative bacterium (Escherichia coli) as well as the methicillin-resistant S. aureus (MRSA) has been previously described. In the present work, new hybrid coumarin-heterocycles have been synthesized via the reaction of coumarin-6-sulfonyl chloride and 6-aminocoumarin with different small heterocycle moieties. The biological efficacy of the new compounds was evaluated towards their ability to inhibit biofilm formation and their anti-inflammatory properties. The antimicrobial activities of the newly synthesized compounds were tested against Gram positive bacterium (S. aureus ATCC 6538), Gram negative bacterium (E. coli ATCC 25922), yeast (Candida albicans ATCC 10231) and the fungus (Aspergillus niger NRRL-A326). Compounds 4d, 4e, 4f, 6a and 9 showed significant MIC and MBC values against S. aureus, E. coli, C. albicans, and methicillin-resistant S. aureus (MRSA) with especial incidence on compound 9 which surpasses all the other compounds giving MIC and MBC values of (4.88 and 9.76 µg/mL for S. aureus), (78.13 and 312.5 µg/mL for E. coli), (9.77 and 78.13 µg/mL for C. albicans), and (39.06 and 76.7 µg/mL for MRSA), respectively. With reference to the antibiofilm activity, compound 9 exhibited potent antibiofilm activity with IC50 of 60, 133.32, and 19.67 µg/mL against S. aureus, E. coli, and MRSA, (respectively) considering the reference drug (neomycin). Out of all studied compounds, the anti-inflammatory results indicated that compound 4d effectively inhibited nitric oxide production in lipopolysaccharide-(LPS-) stimulated RAW264.7 macrophage cells, giving NO% inhibition of 70% compared to Sulindac (55.2%).}, }
@article {pmid38642854, year = {2024}, author = {Cichos, KH and Christie, MC and Ponce, BA and Ghanem, ES}, title = {Biofilm Growth on Orthopaedic Cerclage Materials: Nonmetallic Polymers Are Less Resistant to Methicillin-Resistant Staphylococcus Aureus Bacterial Adhesion.}, journal = {The Journal of arthroplasty}, volume = {39}, number = {9S2}, pages = {S469-S475.e1}, doi = {10.1016/j.arth.2024.04.042}, pmid = {38642854}, issn = {1532-8406}, mesh = {*Methicillin-Resistant Staphylococcus aureus/drug effects ; *Biofilms/drug effects ; *Bacterial Adhesion/drug effects ; *Bone Wires/microbiology ; *Polymers ; Humans ; Stainless Steel ; Microscopy, Electron, Scanning ; Materials Testing ; Staphylococcal Infections/prevention &amp; control/microbiology ; Chromium Alloys ; }, abstract = {BACKGROUND: Data on bacterial adhesion to cerclage cables are sparse. We aimed to compare 5 cerclage products for methicillin-resistant Staphylococcus aureus (MRSA) adhesion to determine the claim: Are nonmetallic polymer cables more resistant to bacterial adhesion than common metallic wires and cables?<br><br>METHODS: The following 5 cerclage products were compared: (1) monofilament stainless steel (SS) wires; (2) multifilament SS cables; (3) multifilament cobalt chrome cables; (4) multifilament Vitallium alloy (cobalt-chrome-molybdenum [Co-Cr-Mo]) cables; and (5) multifilament nonmetallic polymer cables. Each was cut into 2 cm lengths and placed into 12-well plates. Of the wells, 5 were wire or cables in trypticase soy broth with MRSA, with the remaining wells being appropriate controls incubated for 24&#xa0;hours at 37&#xb0; C and 5% CO2 with shaking. Wires and cables were prepared and randomly imaged via scanning electron microscopy, with bacterial counts performed on 3 images of 3 different wires or cables per study group. The scanning electron microscopy technician and counting investigator were blinded. Additionally, SS wire and polymer cables were analyzed by microcalorimetry for metabolic activity and bacterial load.<br><br>RESULTS: Bacterial attachment differed significantly between study groups in the middle section (P&#xa0;= .0003). Post hoc comparison showed no difference between groups individually (all P > .05) apart from polymer cables (median 551 bacteria) having significantly increased attached bacteria compared to the Vitallium alloy cable (157, P&#xa0;= .0004), SS cable (101, P&#xa0;= .0004), and SS wire (211, P&#xa0;= .0004). There was no difference between polymer and cobalt chrome cables (133, P&#xa0;= .056). Microcalorimetry supported these results, as polymer cables had a shorter time to max heat flow (6.2 versus 7.5&#xa0;hours, P&#xa0;= .006), increased max heat flow (117 versus 64 uW, P&#xa0;= .045), and increased colony-forming units, indicating an increased bacterial load compared to SS wires.<br><br>CONCLUSIONS: This in&#xa0;vitro study demonstrated that polymer cables have increased MRSA adhesion compared to common metallic wires and cables. Future studies are necessary to confirm the translation of increased bacterial adherence on polymer cables to increased rates of orthopaedic infections.}, }
@article {pmid38642681, year = {2024}, author = {Nirmal, GR and Lin, ZC and Chiu, TS and Alalaiwe, A and Liao, CC and Fang, JY}, title = {Chemo-photothermal therapy of chitosan/gold nanorod clusters for antibacterial treatment against the infection of planktonic and biofilm MRSA.}, journal = {International journal of biological macromolecules}, volume = {268}, number = {Pt 1}, pages = {131673}, doi = {10.1016/j.ijbiomac.2024.131673}, pmid = {38642681}, issn = {1879-0003}, mesh = {*Chitosan/chemistry/pharmacology ; *Methicillin-Resistant Staphylococcus aureus/drug effects ; *Gold/chemistry/pharmacology ; *Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Nanotubes/chemistry ; Animals ; *Photothermal Therapy/methods ; Mice ; Plankton/drug effects ; Staphylococcal Infections/drug therapy/therapy ; Nanocomposites/chemistry ; Microbial Sensitivity Tests ; }, abstract = {Bacterial infections trigger inflammation and impede the closure of skin wounds. The misuse of antibiotics exacerbates skin infections by generating multidrug-resistant bacteria. In this study, we developed chemo-photothermal therapy (chemo-PTT) based on near-infrared (NIR)-irradiated chitosan/gold nanorod (GNR) clusters as anti-methicillin-resistant Staphylococcus aureus (MRSA) agents. The nanocomposites exhibited an average size of 223 nm with a surface charge of 36 mV. These plasmonic nanocomposites demonstrated on-demand and rapid hyperthermal action under NIR. The combined effect of positive charge and PTT by NIR-irradiated nanocomposites resulted in a remarkable inhibition rate of 96 % against planktonic MRSA, indicating a synergistic activity compared to chitosan nanoparticles or GNR alone. The nanocomposites easily penetrated the biofilm matrix. The combination of chemical and photothermal treatments by NIR-stimulated clusters significantly damaged the biofilm structure, eradicating MRSA inside the biomass. NIR-irradiated chitosan/GNR clusters increased the skin temperature of mice by 13 °C. The plasmonic nanocomposites induced negligible skin irritation in vivo. In summary, this novel nanosystem demonstrated potent antibacterial effects against planktonic and biofilm MRSA, showcasing the possible efficacy in treating skin infections.}, }
@article {pmid38642641, year = {2024}, author = {Savadiya, B and Pandey, G and Misra, SK}, title = {Remediation of pharmacophoric laboratory waste by using biodegradable carbon nanoparticles of bacterial biofilm origin.}, journal = {Environmental research}, volume = {252}, number = {Pt 2}, pages = {118969}, doi = {10.1016/j.envres.2024.118969}, pmid = {38642641}, issn = {1096-0953}, mesh = {*Biofilms/drug effects ; *Carbon/chemistry ; *Bacillus subtilis/drug effects ; *Nanoparticles/chemistry ; Biodegradation, Environmental ; Environmental Restoration and Remediation/methods ; }, abstract = {Research laboratories generate a broad range of hazardous pharmacophoric chemical contaminants, from drugs to dyes used during various experimental procedures. In the recent past, biological methods have demonstrated great potential in the remediation of such contaminants. However, the presence of pharmacophoric chemicals containing antibiotics, xenobiotics, and heavy metals suppresses the growth and survivability of used microbial agents, thus decreasing the overall efficiency of biological remediation processes. Bacterial biofilm is a natural arrangement to counter some of these inhibitions but its use in a systemic manner, portable devices, and pollutant remediation plants post serious challenges. This could be countered by synthesizing a biodegradable carbon nanoparticle from bacterial biofilm. In this study, extracellular polymeric substance-based carbon nanoparticles (Bio-EPS-CNPs) were synthesized from bacterial biofilm derived from Bacillus subtilis NCIB 3610, as a model bacterial system. The produced Bio-EPS-CNPs were investigated for physiochemical properties by dynamic light scattering, optical, Fourier-transformed infrared, and Raman spectroscopy techniques, whereas X-ray diffraction study, scanning electron microscopy, and transmission electron microscopy were used to investigate structural and morphological features. The Bio-EPS-CNPs exhibited negative surface charge with spherical morphology having a uniform size of sub-100 nm. The maximum remediation of some laboratory-produced pharmacophoric chemicals was achieved through a five-round scavenging process and confirmed by UV/Vis spectroscopic analysis with respect to the used pharmacophore. This bioinspired remediation of used pharmacophoric chemicals was achieved through the mechanism of surface adsorption via hydrogen bonding and electrostatic interactions, as revealed by different characterizations. Further experiments were performed to investigate the effects of pH, temperature, stirring, and the protocol of scavenging to establish Bio-EPS-CNP as a possible alternative to be used in research laboratories for efficient removal of pharmacophoric chemicals by incorporating it in a portable, filter-based device.}, }
@article {pmid38642171, year = {2024}, author = {Araujo, TT and Dionizio, A and Carvalho, TS and Boas Feitosa, CMV and Vertuan, M and Câmara, JVF and Henrique-Silva, F and Marchetto, R and Chiaratti, MR and Santos, AC and Alves, LO and Ferro, M and Buzalaf, MAR}, title = {Acquired enamel pellicle and biofilm engineering with a combination of acid-resistant proteins (CaneCPI-5, StN15, and Hemoglobin) for enhanced protection against dental caries - in vivo and in vitro investigations.}, journal = {Clinical oral investigations}, volume = {28}, number = {5}, pages = {261}, pmid = {38642171}, issn = {1436-3771}, support = {2019/08032-5//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado de S&#xe3;o Paulo/ ; 2019/26070-1//Funda&#xe7;&#xe3;o de Amparo &#xe0; Pesquisa do Estado de S&#xe3;o Paulo/ ; 302371/2018-4 ; 304554/2023-5//Conselho Nacional de Desenvolvimento Cient&#xed;fico e Tecnol&#xf3;gico/ ; }, mesh = {Humans ; Dental Pellicle/chemistry/microbiology ; *Dental Caries/prevention &amp; control ; Proteomics ; Biofilms ; Hemoglobins/analysis ; *Tooth Demineralization/prevention &amp; control ; }, abstract = {OBJECTIVE: This study was designed in two-legs. In the in vivo, we explored the potential of a rinse solution containing a combination (Comb) of 0.1 mg/mL CaneCPI-5 (sugarcane-derive cystatin), 1.88 × 10[- 5]M StN15 (statherin-derived peptide) and 1.0 mg/mL hemoglobin (Hb) to change the protein profile of the acquired enamel pellicle(AEP) and the microbiome of the enamel biofilm. The in vitro, was designed to reveal the effects of Comb on the viability and bacterial composition of the microcosm biofilm, as well as on enamel demineralization.<br><br>MATERIALS AND METHODS: In vivo study, 10 participants rinsed (10mL,1&#xa0;min) with either deionized water (H2O-control) or Comb. AEP and biofilm were collected after 2 and 3&#xa0;h, respectively, after rinsing. AEP samples underwent proteomics analysis, while biofilm microbiome was assessed via 16&#xa0;S-rRNA Next Generation Sequencing(NGS). In vitro study, a microcosm biofilm protocol was employed. Ninety-six enamel specimens were treated with: 1)Phosphate-Buffered Solution-PBS(negative-control), 2)0.12%Chlorhexidine, 3)500ppmNaF and 4)Comb. Resazurin, colony-forming-units(CFU) and Transversal Microradiography(TMR) were performed.<br><br>RESULTS: The proteomic results revealed higher quantity of proteins in the Comb compared to control associated with immune system response and oral microbial adhesion. Microbiome showed a significant increase in bacteria linked to a healthy microbiota, in the Comb group. In the in vitro study, Comb group was only efficient in reducing mineral-loss and lesion-depth compared to the PBS.<br><br>CONCLUSIONS: The AEP modification altered the subsequent layers, affecting the initial process of bacterial adhesion of pathogenic and commensal bacteria, as well as enamel demineralization.<br><br>CLINICAL RELEVANCE: Comb group shows promise in shaping oral health by potentially introducing innovative approaches to prevent enamel demineralization and deter tooth decay.}, }
@article {pmid38641883, year = {2024}, author = {Pethe, A and Debnath, M}, title = {Wastewater treatment using moving bed biofilm reactor technology: a case study of ceramic industry.}, journal = {Water environment research : a research publication of the Water Environment Federation}, volume = {96}, number = {4}, pages = {e11026}, doi = {10.1002/wer.11026}, pmid = {38641883}, issn = {1554-7531}, support = {EF/2019-20/QEO4-01//Manipal University Jaipur/ ; }, mesh = {*Waste Disposal, Fluid ; Biofilms ; Bioreactors ; *Water Purification ; Water ; }, abstract = {Biological approaches and coagulation are frequently used to reduce the chemical oxygen demand (COD) for treatment of ceramic effluent water. The technology known as the moving bed biofilm reactor (MBBR) can accomplish this goal. Further, the process of emulsification-aided innovative MBBR using biosurfactants can be proposed for ceramic effluent treatment. In a step-by-step upgrading scheme, biosurfactants and a consortia of halophilic and halotolerant microbial culture was utilized for the treatment of the effluent water. Over the course of 21 days, a progressive decrease in COD of up to 95.79% was achieved. Over the next 48 h period, the biochemical oxygen demand (BOD) was reduced by 98.3%, while total suspended solids (TSS) decreased by 79.41%. With the use of this innovative MBBR technology, biofilm formation accelerated, lowering the COD, BOD, and TSS levels. This allows treated water to be used for further research on recycling it back into the ceramics sector and repurposing it for agricultural purposes. PRACTITIONER POINTS: Implementation of modified MBBR technology for the treatment of effluent water. Biosurfactants could reduce in the organic and inorganic loads. Increase in MLSS values with COD removal observed. The plant operations without the use of chemical coagulants was effective with biosurfactants. Biofilm formation on carriers was scraped and the presence of surfactin and rhamnolipid was confirmed.}, }
@article {pmid38641593, year = {2024}, author = {Raj, K and Paul, D and Rishi, P and Shukla, G and Dhotre, D and YogeshSouche, }, title = {Decoding the role of oxidative stress resistance and alternative carbon substrate assimilation in the mature biofilm growth mode of Candida glabrata.}, journal = {BMC microbiology}, volume = {24}, number = {1}, pages = {128}, pmid = {38641593}, issn = {1471-2180}, mesh = {*Candida glabrata/genetics/metabolism ; *Oleic Acid/metabolism ; Carbon/metabolism ; Glycerol ; Antifungal Agents/metabolism ; Oxidative Stress ; Biofilms ; Glucose/metabolism ; Glyoxylates/metabolism ; }, abstract = {BACKGROUND: Biofilm formation is viewed as a vital mechanism in C. glabrata pathogenesis. Although, it plays a significant role in virulence but transcriptomic architecture and metabolic pathways governing the biofilm growth mode of C. glabrata remain elusive. The present study intended to investigate the genes implicated in biofilm growth phase of C. glabrata through global transcriptomic approach.<br><br>RESULTS: Functional analysis of Differentially expressed genes (DEGs) using gene ontology and pathways analysis revealed that upregulated genes are involved in the glyoxylate cycle, carbon-carbon lyase activity, pre-autophagosomal structure membrane and vacuolar parts whereas, down- regulated genes appear to be associated with glycolysis, ribonucleoside biosynthetic process, ribosomal and translation process in the biofilm growth condition. The RNA-Seq expression of eight selected DEGs (CgICL1, CgMLS1, CgPEP1, and CgNTH1, CgERG9, CgERG11, CgTEF3, and CgCOF1) was performed with quantitative real-time PCR (RT-qPCR). The gene expression profile of selected DEGs with RT-qPCR displayed a similar pattern of expression as observed in RNA-Seq.&#xa0;Phenotype screening of mutant strains generated for genes CgPCK1 and CgPEP1, showed that Cgpck1&#x2206; failed to grow on alternative carbon substrate (Glycerol, Ethanol, Oleic acid) and similarly, Cgpep1&#x2206; unable to grow on YPD medium supplemented with hydrogen peroxide. Our results suggest that in the absence of glucose, C. glabrata assimilate glycerol, oleic acid and generate acetyl coenzyme-A (acetyl-CoA) which is a central and connecting metabolite between catabolic and anabolic pathways (glyoxylate and gluconeogenesis) to produce glucose and fulfil energy requirements.<br><br>CONCLUSIONS: The study was executed using various approaches (transcriptomics, functional genomics and gene deletion) and it revealed that metabolic plasticity of C. glabrata (NCCPF-100,037) in biofilm stage modulates its virulence and survival ability to counter the stress and may promote its transition from commensal to opportunistic pathogen. The observations deduced from the present study along with future work on characterization of the proteins involved in this intricate process may prove to be beneficial for designing novel antifungal strategies.}, }
@article {pmid38641269, year = {2024}, author = {Youssef Moustafa, AM and Fawzy, MM and Kelany, MS and Hassan, YA and Elsharaawy, RFM and Mustafa, FHA}, title = {Synthesis of new quaternized chitosan Schiff bases and their N-alkyl derivatives as antimicrobial and anti-biofilm retardants in membrane technology.}, journal = {International journal of biological macromolecules}, volume = {267}, number = {Pt 2}, pages = {131635}, doi = {10.1016/j.ijbiomac.2024.131635}, pmid = {38641269}, issn = {1879-0003}, mesh = {*Chitosan/chemistry/pharmacology/analogs &amp; derivatives/chemical synthesis ; *Schiff Bases/chemistry/pharmacology/chemical synthesis ; *Biofilms/drug effects ; *Membranes, Artificial ; *Anti-Infective Agents/pharmacology/chemistry/chemical synthesis ; Anti-Bacterial Agents/pharmacology/chemical synthesis/chemistry ; Microbial Sensitivity Tests ; }, abstract = {New quaternized salicylidene chitosan Schiff bases (QSCSBs) and their N-octyl derivatives (OQCs) have been synthesized and characterized, aiming to develop innovative antimicrobial and anti-biofilm agents. This research holds immense potential, as these compounds could be utilized as anti-biofouling additives in membrane technology in the future. The synthesis involved the modification of low molecular-weight-chitosan (LMC) through simultaneous Schiff base formation and quaternization processes to create QSCSBs. Subsequently, QSCSBs were catalytically reduced to form quaternized N-benzyl chitosan (QBCs) intermediates, which then underwent nucleophilic substitution reactions affording N-octyl quaternized chitosans (OQCs). Characterization techniques such as elemental, spectral, and microscopic analyses were used to confirm the successful synthesis of these materials. As membrane technology relies on surface charge, QSCSBs and OQCs with large zeta potentials could be used as positively charged additives. Moreover, SEM image revealed the regular distribution of pores and voids across the additives' surfaces raises intriguing questions about their implications for membrane performance. Meanwhile, the superior antibacterial and antibiofilm potential of these materials, particularly QSCSB2 and OQC2, indicate that the utilization of these compounds as anti-biofouling additives in membrane technology could significantly improve the performance and longevity of membranes used in various applications such as water treatment and desalination.}, }
@article {pmid38640776, year = {2024}, author = {Ganesh, PS}, title = {4-hydroxy-3-methoxybenzaldehyde causes attrition of biofilm formation and quorum sensing-associated virulence factors of Streptococcus mutans.}, journal = {Archives of oral biology}, volume = {163}, number = {}, pages = {105976}, doi = {10.1016/j.archoralbio.2024.105976}, pmid = {38640776}, issn = {1879-1506}, mesh = {*Streptococcus mutans/drug effects ; *Biofilms/drug effects ; *Quorum Sensing/drug effects ; *Benzaldehydes/pharmacology ; *Microbial Sensitivity Tests ; *Virulence Factors ; *Anti-Bacterial Agents/pharmacology ; Polysaccharides, Bacterial/pharmacology ; Microscopy, Electron, Scanning ; In Vitro Techniques ; }, abstract = {OBJECTIVE: The present study investigated the effects of 4-hydroxy-3-methoxybenzaldehyde (4-H-3-MB) against Streptococcus mutans (S. mutans) using an in vitro cariogenic biofilm model.<br><br>DESIGN: The antimicrobial susceptibility of biofilm-forming S. mutans was evaluated by disc diffusion method. In vitro investigations were performed using crystal violet staining assay (biofilm assay), exopolysaccharide (EPS) assay, acid production, growth curve analysis, optical microscopic, and FE-SEM analyses to determine the antibiofilm activity of 4-H-3-MB.<br><br>RESULTS: S. mutans (SDC-05) was resistant to ampicillin, piperacillin/tazobactam and ceftriaxone, whereas the other strains of S. mutans (SDC-01, 02, 03 and SDC-04) were sensitive to all the antibiotics tested. 4-H-3-MB showed promising antibiofilm activity on S. mutans UA159 (79.81 %, 67.76 % and 56.31 %) and S. mutans SDC-05 (77.00 %, 59.48 % and 48.22 %) at the lowest concentration of 0.2, 0.1, 0.05&#xa0;mg/ml. 4-H-3-MB did not inhibit bacterial growth even at concentrations 0.2&#xa0;mg/ml. Similarly, 4-H-3-MB led to significant attrition in exopolysaccharide (EPS) and acid production by S. mutans UA159 and S. mutans (SDC-05) at the concentration of 0.2, 0.1&#xa0;mg/ml, respectively. Optical microscopy and FE-SEM analysis 4-H-3-MB reduced the biofilm thickness of S. mutans UA159 and S. mutans SDC-05 relative to the untreated specimens.<br><br>CONCLUSION: 4-H-3-MB significantly inhibited biofilm formation by S. mutans in a dose-dependent manner. Hence, our findings indicate that the active principle of 4-H-3-MB could be used as a biofilm inhibiting agent against S. mutans.}, }
@article {pmid38640499, year = {2024}, author = {Jakkampudi, T and Lin, Q and Mitra, S and Vijai, A and Qin, W and Kang, A and Chen, J and Ryan, E and Wang, R and Gong, Y and Heinrich, F and Song, J and Di, YP and Tristram-Nagle, S}, title = {Correction to "Lung SPLUNC1 Peptide Derivatives in the Lipid Membrane Headgroup Kill Gram-Negative Planktonic and Biofilm Bacteria".}, journal = {Biomacromolecules}, volume = {25}, number = {5}, pages = {3215}, doi = {10.1021/acs.biomac.4c00501}, pmid = {38640499}, issn = {1526-4602}, support = {R01 AI133351/AI/NIAID NIH HHS/United States ; R01 GM101647/GM/NIGMS NIH HHS/United States ; }, }
@article {pmid38639582, year = {2024}, author = {Upadhyay, A and Pal, D and Kumar, A}, title = {Molecular drilling to combat salmonella typhi biofilm using L-Asparaginase via multiple targeting process.}, journal = {Expert opinion on therapeutic targets}, volume = {28}, number = {4}, pages = {323-334}, doi = {10.1080/14728222.2024.2344699}, pmid = {38639582}, issn = {1744-7631}, mesh = {*Anti-Bacterial Agents/pharmacology ; *Asparaginase/pharmacology/isolation &amp; purification ; Bacterial Proteins/metabolism ; *Biofilms/drug effects ; Drug Design ; Drug Resistance, Bacterial ; *Molecular Docking Simulation ; Molecular Targeted Therapy ; *Salmonella typhi/drug effects ; }, abstract = {OBJECTIVES: Salmonella Typhibiofilm condition is showing as a major public health problem due to the development of antibiotic resistance and less available druggable target proteins. Therefore, we aimed to identify some more druggable targets of S. Typhibiofilm using computational drilling at the genome/proteome level so that the target shortage problem could be overcome and more antibiofilm agents could be designed in the future against the disease.<br><br>METHODS: We performed protein-protein docking and interaction analysis between the homological identified target proteins of S.Typhi biofilm and a therapeutic protein L-Asparaginase.<br><br>RESULTS: We have identified some druggable targets CsgD, BcsA, OmpR, CsgG, CsgE, and CsgF in S.Typhi. These targets showed high-binding affinity BcsA (-219.8&#x2009;Kcal/mol) >csgF (-146.52&#x2009;Kcal/mol) >ompR (-135.68&#x2009;Kcal/mol) >CsgE (-134.66&#x2009;Kcal/mol) >CsgG (-113.81&#x2009;Kcal/mol) >CsgD(-95.39&#x2009;Kcal/mol) with therapeutic enzyme L-Asparaginase through various hydrogen-bonds and salt-bridge. We found six proteins of S. Typhi biofilm from the Csg family as druggable multiple targets.<br><br>CONCLUSION: This study provides insight into the idea of identification of new druggable targets and their multiple targeting with L-Asparaginase to overcome target shortage in S. Typhibiofilm-mediated infections. Results further indicated that L-Asparaginase could potentially be utilized as an antibiofilm biotherapeutic agent against S.Typhi.}, }
@article {pmid38639133, year = {2024}, author = {Mamba, PP and Msagati, TAM and Mamba, BB and Motsa, MM and Nkambule, TTI}, title = {The removal of pathogenic bacteria and dissolved organic matter from freshwater using microporous membranes: insights into biofilm formation and fouling reversibility.}, journal = {Biofouling}, volume = {40}, number = {3-4}, pages = {245-261}, doi = {10.1080/08927014.2024.2339438}, pmid = {38639133}, issn = {1029-2454}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Biofouling/prevention &amp; control ; *Membranes, Artificial ; *Water Purification/methods ; *Fresh Water/microbiology ; *Bacteria/drug effects ; Humic Substances/analysis ; Filtration/methods ; Parabens/chemistry ; Sulfones/chemistry ; Polymers/chemistry ; }, abstract = {Pathogenic bacteria in drinking-water pose a health risk to consumers, as they compromise the quality of portable water. Chemical disinfection of water containing dissolved organic matter (DOM) causes harmful disinfection by-products. In this work, 4-hydroxybenzoic acid (4-HBA) blended polyethersulfone membranes were fabricated and characterised using microscopic and spectroscopic techniques. The membranes were evaluated for the removal of bacteria and DOM from synthetic and environmental water. Permeate flux increased from 287.30 to 374.60 l m[-2] h[-1] at 3 bars when 4-HBA increased from 0 to 1.5 wt.%, suggesting that 4-HBA influenced the membrane's affinity for water. Furthermore, 4-HBA demonstrated antimicrobial properties by inhibiting bacterial growth. The membrane with 1 wt.% 4-HBA recorded 99.4 and 100% bacteria removal in synthetic and environmental water, respectively. Additionally, DOM removal of 55-73% was achieved. A flux recovery ratio (FRR) of 94.6% was obtained when a mixture of bacteria and humic acid was filtered, implying better fouling layer reversibility during cleaning. Furthermore, 100% FRR was achieved when a multimedia granular filtration step was installed prior to membrane filtration. The results illustrated that the membranes had a high permeate flux with low irreversible fouling. This indicated the potential of the membranes in treating complex feed streams using simple cleaning protocols.}, }
@article {pmid38638833, year = {2024}, author = {Zhang, W and He, M and Kong, N and Niu, Y and Li, A and Yan, Y}, title = {Study on the inhibition activity and mechanism of Tanreqing against Klebsiella pneumoniae biofilm formation in vitro and in vivo.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1368450}, pmid = {38638833}, issn = {2235-2988}, mesh = {Animals ; Guinea Pigs ; Klebsiella pneumoniae/genetics ; Quorum Sensing ; Biofilms ; Anti-Bacterial Agents/pharmacology ; *Pneumonia ; *Klebsiella Infections/drug therapy/microbiology ; *Drugs, Chinese Herbal ; }, abstract = {OBJECTIVE: To evaluate the antibacterial effect of Tanreqing (TRQ) against K. pneumoniae and its inhibition activity on bacterial biofilm formation in vitro and in vivo, and to explore the mechanism of the inhibitory effects of TRQ on K. pneumoniae biofilm formation.<br><br>METHODS: An in vitro biofilm model of K. pneumoniae was established, and the impact of TRQ on biofilm formation was evaluated using crystal violet staining and scanning electron microscopy (SEM). Furthermore, the clearance effect of TRQ against K. pneumoniae in the biofilm was assessed using the viable plate counting method; q-RT PCR was used to evaluate the inhibitory effect of different concentrations of TRQ on the expression of biofilm-related genes in Klebsiella pneumoniae; The activity of quorum sensing signal molecule AI-2 was detected by Vibrio harveyi bioluminescence assay; Meanwhile, a guinea pig lung infection model of Klebsiella pneumoniae was constructed, and after treated with drugs, pathological analysis of lung tissue and determination of bacterial load in lung tissue were performed. The treatment groups included TRQ group, imipenem(IPM) group, TRQ+IPM group, and sterile saline group as the control.<br><br>RESULTS: The formation of K. pneumoniae biofilm was significantly inhibited by TRQ in vitro experiments. Furthermore, when combined with IPM, the clearance of K. pneumoniae in the biofilm was notably increased compared to the TRQ group and IPM group alone. q-RT PCR analysis revealed that TRQ down-regulated the expression of genes related to biofilm formation in K. pneumoniae, specifically luxS, wbbm, wzm, and lsrK, and also inhibited the activity of AI-2 molecules in the bacterium. In vivo experiments demonstrated that TRQ effectively treated guinea pig lung infections, resulting in reduced lung inflammation. Additionally, when combined with IPM, there was a significant reduction in the bacterial load in lung tissue.<br><br>CONCLUSION: TRQ as a potential therapeutic agent plays a great role in the treatment of K. pneumoniae infections, particularly in combination with conventional antibiotics. And TRQ can enhanced the clearance effect on the bacterium by inhibiting the K. pneumoniae biofilm formation, which provided experimental evidence in support of clinical treatment of TRQ against K. pneumoniae infections.}, }
@article {pmid38637715, year = {2024}, author = {Taglialegna, A}, title = {Shaking up that sick feeling with biofilm sugars.}, journal = {Nature reviews. Microbiology}, volume = {22}, number = {6}, pages = {323}, pmid = {38637715}, issn = {1740-1534}, mesh = {*Biofilms/growth &amp; development ; Humans ; Sugars/metabolism ; }, }
@article {pmid38637093, year = {2024}, author = {Melian, C and Ploper, D and Chehín, R and Vignolo, G and Castellano, P}, title = {Impairment of Listeria monocytogenes biofilm developed on industrial surfaces by Latilactobacillus curvatus CRL1579 bacteriocin.}, journal = {Food microbiology}, volume = {121}, number = {}, pages = {104491}, doi = {10.1016/j.fm.2024.104491}, pmid = {38637093}, issn = {1095-9998}, mesh = {*Listeria monocytogenes ; Biofilms ; *Bacteriocins/pharmacology ; *Listeria ; Lactobacillus ; Stainless Steel/analysis ; Food Microbiology ; }, abstract = {The effect of lactocin AL705, bacteriocin produced by Latilactobacillus (Lat.) curvatus CRL1579 against Listeria biofilms on stainless steel (SS) and polytetrafluoroethylene (PTFE) coupons at 10 °C was investigated. L. monocytogenes FBUNT showed the greatest adhesion on both surfaces associated to the hydrophobicity of cell surface. Partially purified bacteriocin (800 UA/mL) effectively inhibited L. monocytogenes preformed biofilm through displacement strategy, reducing the pathogen by 5.54 ± 0.26 and 4.74 ± 0.05 log cycles at 3 and 6 days, respectively. The bacteriocin-producer decreased the pathogen biofilm by ∼2.84 log cycles. Control and Bac[-] treated samples reached cell counts of 7.05 ± 0.18 and 6.79 ± 0.06 log CFU/cm[2] after 6 days of incubation. Confocal scanning laser microscopy (CLSM) allowed visualizing the inhibitory effect of lactocin AL705 on L. monocytogenes preformed biofilms under static and hydrodynamic flow conditions. A greater effect of the bacteriocin was found at 3 days independently of the surface matrix and pathogen growth conditions at 10 °C. As a more realistic approach, biofilm displacement strategy under continuous flow conditions showed a significant loss of biomass, mean thickness and substratum coverage of pathogen biofilm. These findings highlight the anti-biofilm capacity of lactocin AL705 and their potential application in food industries.}, }
@article {pmid38637079, year = {2024}, author = {Abi Assaf, J and Holden, ER and Trampari, E and Webber, MA}, title = {Common food preservatives impose distinct selective pressures on Salmonella Typhimurium planktonic and biofilm populations.}, journal = {Food microbiology}, volume = {121}, number = {}, pages = {104517}, doi = {10.1016/j.fm.2024.104517}, pmid = {38637079}, issn = {1095-9998}, mesh = {*Salmonella typhimurium ; Food Preservatives/pharmacology ; Biofilms ; Anti-Bacterial Agents/pharmacology ; *Anti-Infective Agents ; Bacteria ; }, abstract = {Food preservatives are crucial in controlling microbial growth in processed foods to maintain food safety. Bacterial biofilms pose a threat in the food chain by facilitating persistence on a range of surfaces and food products. Cells in a biofilm are often highly tolerant of antimicrobials and can evolve in response to antimicrobial exposure. Little is known about the efficacy of preservatives against biofilms and their potential impact on the evolution of antimicrobial resistance. In this study we investigated how Salmonella enterica serovar Typhimurium responded to subinhibitory concentrations of four food preservatives (sodium chloride, potassium chloride, sodium nitrite or sodium lactate) when grown planktonically and in biofilms. We found that each preservative exerted a unique selective pressure on S. Typhimurium populations. There was a trade-off between biofilm formation and growth in the presence of three of the four preservatives, where prolonged preservative exposure resulted in reduced biofilm biomass and matrix production over time. All three preservatives selected for mutations in global stress response regulators rpoS and crp. There was no evidence for any selection of cross-resistance to antibiotics after preservative exposure. In conclusion, we showed that preservatives affect biofilm formation and bacterial growth in a compound specific manner. We showed trade-offs between biofilm formation and preservative tolerance, but no antibiotic cross-tolerance. This indicates that bacterial adaptation to continuous preservative exposure, is unlikely to affect food safety or contribute to antibiotic resistance.}, }
@article {pmid38636891, year = {2024}, author = {Shaghayegh, G and Cooksley, C and Bouras, G and Panchatcharam, BS and Feizi, S and Javadian, S and Ramezanpour, M and Fenix, KA and Wormald, PJ and Psaltis, AJ and Vreugde, S}, title = {S. aureus biofilm properties correlate with immune B cell subset frequencies and severity of chronic rhinosinusitis.}, journal = {Clinical immunology (Orlando, Fla.)}, volume = {263}, number = {}, pages = {110221}, doi = {10.1016/j.clim.2024.110221}, pmid = {38636891}, issn = {1521-7035}, mesh = {Adult ; Aged ; Female ; Humans ; Male ; Middle Aged ; B-Lymphocytes/immunology ; *Biofilms ; Chronic Disease ; Nasal Mucosa/immunology/microbiology ; Nasal Polyps/immunology/microbiology ; *Rhinosinusitis/immunology/microbiology ; Severity of Illness Index ; *Staphylococcal Infections/immunology/microbiology ; Staphylococcus aureus/immunology ; }, abstract = {Staphylococcus aureus mucosal biofilms are associated with recalcitrant chronic rhinosinusitis (CRS). However, S. aureus colonisation of sinus mucosa is frequent in the absence of mucosal inflammation. This questions the relevance of S. aureus biofilms in CRS etiopathogenesis. This study aimed to investigate whether strain-level variation in in vitro-grown S. aureus biofilm properties relates to CRS disease severity, in vitro toxicity, and immune B cell responses in sinonasal tissue from CRS patients and non-CRS controls. S. aureus clinical isolates, tissue samples, and matched clinical datasets were collected from CRS patients with nasal polyps (CRSwNP), CRS without nasal polyps (CRSsNP), and controls. B cell responses in tissue samples were characterised by FACS. S. aureus biofilms were established in vitro, followed by measuring their properties of metabolic activity, biomass, colony-forming units, and exoprotein production. S. aureus virulence was evaluated using whole-genome sequencing, mass spectrometry and application of S. aureus biofilm exoproteins to air-liquid interface cultures of primary human nasal epithelial cells (HNEC-ALI). In vitro S. aureus biofilm properties were correlated with increased CRS severity scores, infiltration of antibody-secreting cells and loss of regulatory B cells in tissue samples. Biofilm exoproteins from S. aureus with high biofilm metabolic activity had enriched virulence genes and proteins, and negatively affected the barrier function of HNEC-ALI cultures. These findings support the notion of strain-level variation in S. aureus biofilms to be critical in the pathophysiology of CRS.}, }
@article {pmid38636465, year = {2024}, author = {Rattanapakdeekul, N and Lapirattanakul, J and Tosrisawatkasem, O and Surarit, R and Smutkeeree, A}, title = {Evaluation of Streptococcus mutans Biofilm Formation and Acidogenicity of Infant Milk Formulas for Treating Cow Milk Allergy: An in vitro Study.}, journal = {Caries research}, volume = {58}, number = {5}, pages = {478-487}, doi = {10.1159/000538882}, pmid = {38636465}, issn = {1421-976X}, mesh = {*Biofilms ; *Streptococcus mutans ; *Infant Formula ; Hydrogen-Ion Concentration ; *Milk Hypersensitivity ; Humans ; Animals ; Infant ; *Sucrose ; Milk ; Microscopy, Confocal ; Lactic Acid/analysis/metabolism ; In Vitro Techniques ; Cattle ; }, abstract = {INTRODUCTION: When infants cannot consume breast milk, the most commonly available alternative milk formula is cow milk-based. Due to a rise in the prevalence of cow milk protein allergy (CMPA) among children, this study aimed to assess the biofilm formation and acidogenicity of cow milk-based formulas as well as milk formulas suggested for children with CMPA.<br><br>METHODS: Cow milk-based formulas with 0%, 10%, or 18% sucrose added, partially hydrolyzed formula (pHF), extensively hydrolyzed formula (eHF), amino acid-based formula (AAF), and soy-based formulas with 0%, or 11% sucrose added were evaluated. Streptococcus mutans was used as a representative microorganism associated with caries. The acidogenicity after 24-h incubation was assessed by the pH of the formed biofilm and lactic acid formation. Biofilm formation was quantified using crystal violet staining. Additionally, the biofilm characteristics were determined using confocal laser scanning microscopy (CLSM). Comparisons were made among formulas without added sucrose to observe protein-based differences. Furthermore, formulas with different sucrose percentages were compared to explore the impact of sucrose content.<br><br>RESULTS: When comparing the formulas without added sucrose, the biofilm formation in the cow milk-based formula and pHF were significantly greater than the soy-based formula, eHF, and AAF. In the presence of S. mutans, all formulas reduced the biofilm pH below the critical enamel pH. The cow milk-based formula and AAF showed a significantly lower biofilm pH than the pHF, soy-based, and eHF groups, while the lactic acid production was markedly higher in the cow milk-based formula, pHF and AAF, compared with the eHF and soy-based formula. Adding sucrose into the cow milk-based and soy-based formulas substantially increased biofilm mass. The biofilm pH of the cow milk-based formulas, with or without sucrose, was significantly lower than that of the soy-based formulas. The CLSM indicated distinct biofilm characteristics among the different protein-based formulas, with sucrose supplementation promoting S. mutans aggregation in cow milk-based formula biofilm and increased density and intact biofilm in the soy-based formula.<br><br>CONCLUSION: All assessed milk formulas had caries-inducing factors, including those without supplemental sucrose. Among them, the eHF demonstrated the least caries-inducing factors, attributed to its minimal biofilm formation and the highest biofilm pH.}, }
@article {pmid38636417, year = {2024}, author = {Liu, Y and Li, J and Su, J and Li, X and Li, X}, title = {Simultaneous removal of ammonia nitrogen, calcium and cadmium in a biofilm reactor based on microbial-induced calcium precipitation: Optimization of conditions, mechanism and community biological response.}, journal = {Journal of environmental management}, volume = {358}, number = {}, pages = {120912}, doi = {10.1016/j.jenvman.2024.120912}, pmid = {38636417}, issn = {1095-8630}, mesh = {*Cadmium/metabolism ; *Biofilms ; *Calcium/metabolism ; *Ammonia/metabolism ; *Bioreactors ; *Nitrogen/metabolism ; Wastewater/chemistry ; Denitrification ; Charcoal/chemistry ; Waste Disposal, Fluid/methods ; }, abstract = {With the enhancement of environmental governance regulations, the discharge requirements for reverse osmosis wastewater have become increasingly stringent. This study proposes an innovative approach utilizing heterotrophic nitrification and aerobic denitrification (HNAD)-based biomineralization technology, combined with coconut palm silk loaded biochar, to offer a novel solution for resource-efficient and eco-friendly treatment of reverse osmosis wastewater. Zobellella denitrificans sp. LX16 were loaded onto modified coir silk and showed removal efficiencies of up to 97.38, 94.58, 86.24, and 100% for NH4[+]-N (65 mg L[-1]), COD (900 mg L[-1]), Ca[2+] (180 mg L[-1]), and Cd[2+] (25 mg L[-1]). Analysis of the metabolites of microorganisms reveals that coconut palm silk loaded with deciduous biochar (BCPS) not only exerts a protective effect on microorganisms, but also enhances their growth, metabolism, and electron transfer capabilities. Characterization of precipitation phenomena elucidated the mechanism of Cd[2+] removal via ion exchange, precipitation, and adsorption. Employing high-throughput and KEGG functional analyses has confirmed the biota environmental response strategies and the identification of key genes like HNAD.}, }
@article {pmid38635841, year = {2024}, author = {Youngblom, MA and Smith, TM and Murray, HJ and Pepperell, CS}, title = {Adaptation of the Mycobacterium tuberculosis transcriptome to biofilm growth.}, journal = {PLoS pathogens}, volume = {20}, number = {4}, pages = {e1012124}, pmid = {38635841}, issn = {1553-7374}, support = {R01 AI113287/AI/NIAID NIH HHS/United States ; }, mesh = {*Biofilms/growth &amp; development ; *Mycobacterium tuberculosis/genetics/growth &amp; development ; *Transcriptome ; *Gene Expression Regulation, Bacterial ; Adaptation, Physiological/genetics ; Humans ; Tuberculosis/microbiology/genetics ; }, abstract = {Mycobacterium tuberculosis (M. tb), the causative agent of tuberculosis (TB), is a leading global cause of death from infectious disease. Biofilms are increasingly recognized as a relevant growth form during M. tb infection and may impede treatment by enabling bacterial drug and immune tolerance. M. tb has a complicated regulatory network that has been well-characterized for many relevant disease states, including dormancy and hypoxia. However, despite its importance, our knowledge of the genes and pathways involved in biofilm formation is limited. Here we characterize the biofilm transcriptomes of fully virulent clinical isolates and find that the regulatory systems underlying biofilm growth vary widely between strains and are also distinct from regulatory programs associated with other environmental cues. We used experimental evolution to investigate changes to the transcriptome during adaptation to biofilm growth and found that the application of a uniform selection pressure resulted in loss of strain-to-strain variation in gene expression, resulting in a more uniform biofilm transcriptome. The adaptive trajectories of transcriptomes were shaped by the genetic background of the M. tb population leading to convergence on a sub-lineage specific transcriptome. We identified widespread upregulation of non-coding RNA (ncRNA) as a common feature of the biofilm transcriptome and hypothesize that ncRNA function in genome-wide modulation of gene expression, thereby facilitating rapid regulatory responses to new environments. These results reveal a new facet of the M. tb regulatory system and provide valuable insight into how M. tb adapts to new environments.}, }
@article {pmid38634060, year = {2024}, author = {Lu, L and Zhao, Y and Li, M and Wang, X and Zhu, J and Liao, L and Wang, J}, title = {Contemporary strategies and approaches for characterizing composition and enhancing biofilm penetration targeting bacterial extracellular polymeric substances.}, journal = {Journal of pharmaceutical analysis}, volume = {14}, number = {4}, pages = {100906}, pmid = {38634060}, issn = {2214-0883}, abstract = {Extracellular polymeric substances (EPS) constitutes crucial elements within bacterial biofilms, facilitating accelerated antimicrobial resistance and conferring defense against the host's immune cells. Developing precise and effective antibiofilm approaches and strategies, tailored to the specific characteristics of EPS composition, can offer valuable insights for the creation of novel antimicrobial drugs. This, in turn, holds the potential to mitigate the alarming issue of bacterial drug resistance. Current analysis of EPS compositions relies heavily on colorimetric approaches with a significant bias, which is likely due to the selection of a standard compound and the cross-interference of various EPS compounds. Considering the pivotal role of EPS in biofilm functionality, it is imperative for EPS research to delve deeper into the analysis of intricate compositions, moving beyond the current focus on polymeric materials. This necessitates a shift from heavy reliance on colorimetric analytic methods to more comprehensive and nuanced analytical approaches. In this study, we have provided a comprehensive summary of existing analytical methods utilized in the characterization of EPS compositions. Additionally, novel strategies aimed at targeting EPS to enhance biofilm penetration were explored, with a specific focus on highlighting the limitations associated with colorimetric methods. Furthermore, we have outlined the challenges faced in identifying additional components of EPS and propose a prospective research plan to address these challenges. This review has the potential to guide future researchers in the search for novel compounds capable of suppressing EPS, thereby inhibiting biofilm formation. This insight opens up a new avenue for exploration within this research domain.}, }
@article {pmid38633196, year = {2024}, author = {Mohammed, AR and El-Said, EI and Abd ElAal, SF and Kamal, RM}, title = {Screening of antibiogram, virulence factors, and biofilm production of Staphylococcus aureus and the bio-control role of some probiotics as alternative antibiotics.}, journal = {Open veterinary journal}, volume = {14}, number = {1}, pages = {176-185}, pmid = {38633196}, issn = {2218-6050}, mesh = {Humans ; Animals ; Staphylococcus aureus/genetics ; Anti-Bacterial Agents/pharmacology ; Virulence Factors/genetics ; Milk ; Enterotoxins/genetics ; *Staphylococcal Infections/microbiology/veterinary ; Microbial Sensitivity Tests/veterinary ; *Anti-Infective Agents ; Biofilms ; *Probiotics ; }, abstract = {BACKGROUND: Food safety is a serious challenge in the face of increasing population and diminishing resources. Staphylococcus aureus is a critical foodborne pathogen characterized by its capability to secret a diverse range of heat-resistant enterotoxins. Antibiotic usage in dairy herds resulted in the occurrence of antimicrobial resistance (AMR) patterns among bacterial species, which were consequently transmitted to humans via dairy products. Lactic acid bacteria (LAB) produce bacteriocins, which provide an excellent source of natural antimicrobials with the further advantage of being environmentally friendly and safe.<br><br>AIM: Detection of multidrug resistance (MDR) S. aureus isolates in concerned samples, molecular characteristics, biofilm production, and the inhibitory role of LAB against it.<br><br>METHODS: Random samples of raw milk and other dairy products were analyzed for S. aureus isolation. Phenotypic and genotypic assessment of AMR was performed, in addition to detection of classical enterotoxin genes of S. aureus. Finally, evaluation of the antimicrobial action of some Lactobacillus strains against S. aureus.<br><br>RESULTS: Incidence rates of presumptive S. aureus in raw milk, Kariesh cheese, and yogurt samples were 50%, 40%, and 60%, respectively. The highest resistance of S. aureus was to Kanamycin (100%) and Nalidixic acid (89.3%), respectively. (78.66%) of S. aureus were MDR. 11.1% of S. aureus carried mecA gene. In concern with enterotoxins genes, PCR showed that examined isolates harbored sea with a percentage of (22.2%), while sed was found in (11.1%) of isolates. Regarding biofilm production, (88.88%) of S. aureus were biofilm producers. Finally, agar well diffusion showed that Lactobacillus acidophilus had the strongest antimicrobial action against S. aureus with inhibition zone diameter ranging from 18 to 22 mm.<br><br>CONCLUSION: There is a widespread prevalence of MDR S. aureus in raw milk and dairy products. Production of staphylococcal enterotoxins, as well as biofilm production are responsible for public health risks. Therefore, installing proper hygienic routines and harsh food safety policies at food chain levels is substantial.}, }
@article {pmid38633171, year = {2024}, author = {Elshazely, RMY and Amer, IH and Aal, SFAA and Aal, SFAA and Tahoun, ABMB}, title = {Antibacterial effect of Moringa oleifera on Staphylococcus aureus and Pseudomonas aeruginosa isolated from raw milk and some dairy products with special reference to biofilm gene expression.}, journal = {Open veterinary journal}, volume = {14}, number = {1}, pages = {164-175}, pmid = {38633171}, issn = {2218-6050}, mesh = {Animals ; Staphylococcus aureus/genetics ; Pseudomonas aeruginosa/genetics ; Milk ; *Moringa oleifera/genetics ; Enterotoxins/genetics/metabolism/pharmacology ; Food Microbiology ; Anti-Bacterial Agents/pharmacology ; *Staphylococcal Infections/microbiology/veterinary ; Biofilms ; *Foodborne Diseases/veterinary ; Gene Expression ; }, abstract = {BACKGROUND: Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus) are well defined as food poisoning pathogens that are highly resistant and need continuous studies.<br><br>AIM: The purpose of the work was to examine phenotypic and genotypic characteristics of both P. aeruginosa and S. aureus, and treatment trials with medicinal plants.<br><br>METHODS: Samples were examined for isolation of P. aeruginosa and S. aureus on selective media followed by biochemical confirmation, biofilm formation, genes detection, and expression of P. aeruginosa pslA biofilm gene was performed by quantitative real-time polymerase chain reaction after treatment with 0.312 mg/ml Moringa oleifera aqueous extract as a minimum inhibitory concentration.<br><br>RESULTS: The highest isolation rate of P. aeruginosa was 20% from both raw milk and Kariesh cheese, followed by 16% and 12% from ice cream and processed cheese, respectively, while the highest isolation rate of S. aureus was 36% from raw milk followed by 28% in ice cream and 16% in both Kariesh cheese and processed cheese. 30% of P. aeruginosa isolates were biofilm producers, while only 21% of S. aureus isolates were able to produce biofilm. The P. aeruginosa isolates harbor virulence-associated genes nan1, exoS, toxA, and pslA at 100%, 80%, 40%, and 40%, respectively. Staphylococcus aureus SEs genes were examined in S. aureus strains, where SEA and SEB genes were detected with 60%, but no isolate harbored SEC, SED, or SEE. The significant fold change of P. aeruginosa pslA expression was 0.40332 after treatment with M. oleifera aqueous extract.<br><br>CONCLUSION: Pseudomonas aeruginosa and S. aureus harbor dangerous virulence genes that cause food poisoning, but M. oleifera extract could minimize their action.}, }
@article {pmid38629727, year = {2024}, author = {Xue, Y and Yu, C and Ouyang, H and Huang, J and Kang, X}, title = {Uncovering the Molecular Composition and Architecture of the Bacillus subtilis Biofilm via Solid-State NMR Spectroscopy.}, journal = {Journal of the American Chemical Society}, volume = {146}, number = {17}, pages = {11906-11923}, doi = {10.1021/jacs.4c00889}, pmid = {38629727}, issn = {1520-5126}, mesh = {*Bacillus subtilis/chemistry/metabolism ; *Biofilms ; *Magnetic Resonance Spectroscopy/methods ; Polysaccharides, Bacterial/chemistry/metabolism ; }, abstract = {The complex and dynamic compositions of biofilms, along with their sophisticated structural assembly mechanisms, endow them with exceptional capabilities to thrive in diverse conditions that are typically unfavorable for individual cells. Characterizing biofilms in their native state is significantly challenging due to their intrinsic complexities and the limited availability of noninvasive techniques. Here, we utilized solid-state nuclear magnetic resonance (NMR) spectroscopy to analyze Bacillus subtilis biofilms in-depth. Our data uncover a dynamically distinct organization within the biofilm: a dominant, hydrophilic, and mobile framework interspersed with minor, rigid cores of limited water accessibility. In these heterogeneous rigid cores, the major components are largely self-assembled. TasA fibers, the most robust elements, further provide a degree of mechanical support for the cell aggregates and some lipid vesicles. Notably, rigid cell aggregates can persist even without the major extracellular polymeric substance (EPS) polymers, although this leads to slight variations in their rigidity and water accessibility. Exopolysaccharides are exclusively present in the mobile domain, playing a pivotal role in its water retention property. Specifically, all water molecules are tightly bound within the biofilm matrix. These findings reveal a dual-layered defensive strategy within the biofilm: a diffusion barrier through limited water mobility in the mobile phase and a physical barrier posed by limited water accessibility in the rigid phase. Complementing these discoveries, our comprehensive, in situ compositional analysis is not only essential for delineating the sophisticated biofilm architecture but also reveals the presence of alternative genetic mechanisms for synthesizing exopolysaccharides beyond the known pathway.}, }
@article {pmid38629215, year = {2024}, author = {Quan, K and Mao, Z and Lu, Y and Qin, Y and Wang, S and Yu, C and Bi, X and Tang, H and Ren, X and Chen, D and Cheng, Y and Wang, Y and Zheng, Y and Xia, D}, title = {Composited silk fibroins ensured adhesion stability and magnetic controllability of Fe3O4-nanoparticle coating on implant for biofilm treatment.}, journal = {Materials horizons}, volume = {11}, number = {13}, pages = {3157-3165}, doi = {10.1039/d4mh00097h}, pmid = {38629215}, issn = {2051-6355}, mesh = {*Biofilms/drug effects ; Animals ; Rats ; *Titanium/pharmacology/chemistry ; *Fibroins/chemistry/pharmacology ; Anti-Bacterial Agents/pharmacology/administration &amp; dosage ; Magnetite Nanoparticles/therapeutic use ; Coated Materials, Biocompatible/pharmacology/chemistry ; Prostheses and Implants ; Rats, Sprague-Dawley ; Surface Properties ; Staphylococcus aureus/drug effects ; }, abstract = {Magnetic propulsion of nano-/micro-robots is an effective way to treat implant-associated infections by physically destroying biofilm structures to enhance antibiotic killing. However, it is hard to precisely control the propulsion in vivo. Magnetic-nanoparticle coating that can be magnetically pulled off does not need precise control, but the requirement of adhesion stability on an implant surface restricts its magnetic responsiveness. Moreover, whether the coating has been fully pulled-off or not is hard to ensure in real-time in vivo. Herein, composited silk fibroins (SFMA) are optimized to stabilize Fe3O4 nanoparticles on a titanium surface in a dry environment; while in an aqueous environment, the binding force of SFMA on titanium is significantly reduced due to hydrophilic interaction, making the coating magnetically controllable by an externally-used magnet but still stable in the absence of a magnet. The maximum working distance of the magnet can be calculated using magnetomechanical simulation in which the yielding magnetic traction force is strong enough to pull Fe3O4 nanoparticles off the surface. The pulling-off removes the biofilms that formed on the coating and enhances antibiotic killing both in vitro and in a rat sub-cutaneous implant model by up to 100 fold. This work contributes to the practical knowledge of magnetic propulsion for biofilm treatment.}, }
@article {pmid38628638, year = {2024}, author = {Shariati, A and Noei, M and Askarinia, M and Khoshbayan, A and Farahani, A and Chegini, Z}, title = {Inhibitory effect of natural compounds on quorum sensing system in Pseudomonas aeruginosa: a helpful promise for managing biofilm community.}, journal = {Frontiers in pharmacology}, volume = {15}, number = {}, pages = {1350391}, pmid = {38628638}, issn = {1663-9812}, abstract = {Pseudomonas aeruginosa biofilm is a community of bacteria that adhere to live or non-living surfaces and are encapsulated by an extracellular polymeric substance. Unlike individual planktonic cells, biofilms possess a notable inherent resistance to sanitizers and antibiotics. Overcoming this resistance is a substantial barrier in the medical and food industries. Hence, while antibiotics are ineffective in eradicating P. aeruginosa biofilm, scientists have explored alternate strategies, including the utilization of natural compounds as a novel treatment option. To this end, curcumin, carvacrol, thymol, eugenol, cinnamaldehyde, coumarin, catechin, terpinene-4-ol, linalool, pinene, linoleic acid, saponin, and geraniol are the major natural compounds extensively utilized for the management of the P. aeruginosa biofilm community. Noteworthy, the exact interaction of natural compounds and the biofilm of this bacterium is not elucidated yet; however, the interference with the quorum sensing system and the inhibition of autoinducer production in P. aeruginosa are the main possible mechanisms. Noteworthy, the use of different drug platforms can overcome some drawbacks of natural compounds, such as insolubility in water, limited oral bioavailability, fast metabolism, and degradation. Additionally, drug platforms can deliver different antibiofilm agents simultaneously, which enhances the antibiofilm potential of natural compounds. This article explores many facets of utilizing natural compounds to inhibit and eradicate P. aeruginosa biofilms. It also examines the techniques and protocols employed to enhance the effectiveness of these compounds.}, }
@article {pmid38626650, year = {2024}, author = {Si, B and Yang, Y and Naveed, M and Wang, F and Chan, MWH}, title = {Characterizations of biogenic selenium nanoparticles and their anti-biofilm potential against Streptococcus mutans ATCC 25175.}, journal = {Journal of trace elements in medicine and biology : organ of the Society for Minerals and Trace Elements (GMS)}, volume = {84}, number = {}, pages = {127448}, doi = {10.1016/j.jtemb.2024.127448}, pmid = {38626650}, issn = {1878-3252}, mesh = {*Streptococcus mutans/drug effects/physiology ; *Biofilms/drug effects ; *Selenium/pharmacology/chemistry ; *Nanoparticles/chemistry ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Microbial Sensitivity Tests ; Lactobacillus plantarum/chemistry/metabolism ; Particle Size ; }, abstract = {INTRODUCTION: S. mutans has been identified as the primary pathogenic bacterium in biofilm-mediated dental caries. The biogenic selenium nanoparticles (SeNPs) produced by L. plantarum KNF-5 were used in this study against S. mutans ATCC 25175.<br><br>OBJECTIVES: The aims of this study were: (1) the biosynthesis of SeNPs by L. plantarum KNF-5, (2) the characterization of SeNPs, (3) the investigation of the inhibitory effect of biogenic SeNPs against S. mutans ATCC 25175, and (4) the determination of the anti-biofilm potential of SeNPS against S. mutans ATCC 25175.<br><br>METHODOLOGY: 3&#x202f;mL of the culture was added to 100&#x202f;mL of MRS medium and incubated. After 4&#x202f;h, Na2SeO3 solution (concentration 100&#x202f;&#x3bc;g/mL) was added and incubated at 37 &#xb0;C for 36&#x202f;h. The color of the culture solution changed from brownish-yellow to reddish, indicating the formation of SeNPs. The characterization of SeNPs was confirmed by UV-Vis spectrophotometry, FTIR, SEM-EDS and a particle size analyzer. The antibacterial activity was determined by the disk diffusion method, the MIC by the micro-double dilution method, and the biofilm inhibitory potential by the crystal violet method and the MTT assay. The effect of SeNPs on S. mutans ATCC 25175 was determined using SEM and CLSM spectrometry techniques. The sulfate-anthrone method was used to analyze the effect of SeNPs on insoluble extracellular polysaccharides. The expression of genes in S. mutans ATCC 25175 was analyzed by real-time quantitative polymerase chain reaction (RT-qPCR).<br><br>PREPARATION OF NANOPARTICLES: SeNPs produced by probiotic bacteria are considered a safe method. In this study, L. plantarum KNF-5 (probiotic strain) was used for the production of SeNPs.<br><br>RESULTS: The biogenic SeNPs were spherical and coated with proteins and polysaccharides and had a diameter of about 270&#x202f;nm. The MIC of the SeNPs against S. mutans ATCC 25175 was 3.125&#x202f;mg/mL. Biofilm growth was also significantly suppressed at this concentration. The expression of genes responsible for biofilm formation (GtfB, GtfC, BrpA and GbpB,) was reduced when S. mutans ATCC 25175 was treated with SeNPs.<br><br>CONCLUSION: It was concluded that the biogenic SeNPs produced by L. plantarum KNF-5 was highly effective to inhibit the growth of S. mutans ATCC 25175.<br><br>NOVELTY STATEMENT: The application of biogenic SeNPs, a natural anti-biofilm agent against S. mutans ATCC 25175. In the future, this study will provide a new option for the prevention and treatment of dental caries.}, }
@article {pmid38625517, year = {2024}, author = {Piecuch, A and Cal, M and Ogórek, R}, title = {Adhesion and biofilm formation by two clinical isolates of Trichosporon Cutaneum in various environmental conditions.}, journal = {Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology]}, volume = {55}, number = {2}, pages = {1793-1800}, pmid = {38625517}, issn = {1678-4405}, support = {2020/04/X/NZ9/00644//Narodowe Centrum Nauki/ ; }, mesh = {*Biofilms/growth &amp; development ; *Trichosporon/physiology/isolation &amp; purification/drug effects ; Humans ; Trichosporonosis/microbiology ; Antifungal Agents/pharmacology ; Fluconazole/pharmacology ; }, abstract = {Trichosporon spp. is an emerging opportunistic pathogen and a common cause of both superficial and invasive infections. Although Trichosporon asahii is the most frequently isolated species, Trichosporon cutaneum is also widely observed, as it is the predominant agent in cases of white Piedra and onychomycosis. Trichosporon spp. is a known to produce biofilms, which serve as one of its virulence mechanisms, however, there is limited data available on biofilms formed by T. cutaneum. Thus, the aim of this study was to assess the adhesion and biofilm formation of two clinical isolates of T. cutaneum under various environmental conditions (including temperature, nutrient availability, and carbon source), as well as their tolerance to fluconazole. Adhesion was tested on common abiotic substrates (such as silicone, glass, and stainless steel), revealing that T. cutaneum readily adhered to all surfaces tested. CV staining was applied for the evaluation of the environment influence on biofilm efficiency and it was proved that the nutrient availability has a major impact. Additionaly, fluorescent staining was employed to visualize the morphology of T. cutaneum biofilm and its survival in the presence of fluconazole. Hyphae production was shown to play a role in elevated biofilm production in minimal medium and increased tolerance to fluconazole.}, }
@article {pmid38625380, year = {2024}, author = {Hayatimehr, S and Mirkalantari, S and Amirmozafari, N and Jazi, FM and Moghadam, MT}, title = {Virulence Genes and Biofilm Formation Among Legionella pneumophila Isolates Collected from Hospital Water Sources.}, journal = {Current microbiology}, volume = {81}, number = {6}, pages = {141}, pmid = {38625380}, issn = {1432-0991}, mesh = {Humans ; *Legionella pneumophila/genetics ; Virulence/genetics ; Chlorine/pharmacology ; Iran ; *Legionella ; Biofilms ; Hospitals ; }, abstract = {Legionella pneumophila can be transmitted to people, especially immunocompromised patients, via hospital water pipe systems and cause severe pneumonia. The aim of our study was to investigate the presence of major virulence factor genes, ability of biofilms formation, and correlation between presence of Legionella isolates and temperature, pH, and residual chlorine of water. Hundred water samples were collected from nine hospitals in Tehran, Iran. Temperature, pH, and residual chlorine were determined during sampling. Different virulence genes and the ability to form biofilms were subsequently analyzed among the L. pneumophila isolates. Results showed that 12 (12%) samples were positive in culture method and all of the isolates were positive as L. pneumophila species (mip). A correlation was found between Legionella culture positivity and temperature and pH of water, but there was no significant correlation between residual chlorine of water samples and the presence of Legionella. The isolation of Legionella rate in summer and spring was higher than winter and autumn. Twelve (100%) isolates were positive for mip genes, 9 (75%) for dot genes, 8 (66.66%) for hsp, 6 (50%) for lvh, and 4 (33.33%) for rtx. All of the isolates displayed strong ability for biofilm production every three days. Two of these isolates (16.6%) displayed weak ability to form biofilm on the first day of incubation. This study revealed that water sources in hospitals were colonized by virulent Legionella and should be continuously monitored to avoid elevated concentrations of Legionella with visible biofilm formation.}, }
@article {pmid38625018, year = {2024}, author = {Ma, Z and Sun, Y and Liu, Y and Jiao, J and Li, N and Zuo, Y and Li, Z and Li, Y and Cai, X and Meng, Q and Qiao, J}, title = {STM1863, a Member of the DUFs Protein Family, Is Involved in Environmental Adaptation, Biofilm Formation, and Virulence in Salmonella Typhimurium.}, journal = {Foodborne pathogens and disease}, volume = {}, number = {}, pages = {}, doi = {10.1089/fpd.2023.0139}, pmid = {38625018}, issn = {1556-7125}, abstract = {Salmonella Typhimurium (STM) is an important zoonotic Gram-negative pathogen that can cause infection in a variety of livestock and poultry. Meanwhile, as an important foodborne pathogen, the bacterium can survive in various stressful environments and transmits through the fecal-oral route, posing a serious threat to global food safety. To investigate the roles of STM1863, a member of the DUFs protein family, involved in STM environmental adaptation, biofilm formation, and virulence. We analyzed the molecular characteristics of the protein encoded by STM1863 gene and examined intra- and extracellular expression levels of STM1863 gene in mouse macrophages. Furthermore, we constructed STM1863 gene deletion and complementation strains and determined its environmental adaptation under stressful conditions such as acid, alkali, high salt, bile salt, and oxidation. And the capacity of biofilm formation and pathogenicity of those strains were analyzed and compared. In addition, the interaction between the promoter of STM1863 gene and RcsB protein was analyzed using DNA gel electrophoresis migration assay (electrophoretic mobility shift assay [EMSA]). The experiments revealed that acid adaptability and biofilm formation ability of STM1863 gene deletion strain were significantly weakened compared with the parental and complementary strains. Moreover, the adhesion and invasion ability of STM1863 deletion strain to mouse macrophages was significantly decreased, while the median lethal dose (LD50) increased by 2.148-fold compared with the parental strain. In addition, EMSA confirmed that RcsB protein could bind to the promoter sequence of STM1863 gene, suggesting that the expression of STM1863 gene might be modulated by RcsB. The present study demonstrated for the first time that STM1863, a member of the DUFs protein family, is involved in the modulation of environmental adaptation, biofilm formation, and virulence.}, }
@article {pmid38624207, year = {2024}, author = {Banerjee, A and Kang, C-Y and An, M and Koff, BB and Sunder, S and Kumar, A and Tenuta, LMA and Stockbridge, RB}, title = {Fluoride export is required for the competitive fitness of pathogenic microorganisms in dental biofilm models.}, journal = {mBio}, volume = {15}, number = {5}, pages = {e0018424}, pmid = {38624207}, issn = {2150-7511}, support = {R21 DE032837/DE/NIDCR NIH HHS/United States ; R21 AI178229/AI/NIAID NIH HHS/United States ; R21 AI168571/AI/NIAID NIH HHS/United States ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Candida albicans/drug effects/genetics/physiology/metabolism ; *Streptococcus mutans/genetics/drug effects/metabolism/physiology ; *Fluorides/pharmacology/metabolism ; *Streptococcus gordonii/drug effects/genetics/physiology/metabolism ; Gene Knockout Techniques ; Bacterial Proteins/genetics/metabolism ; Dental Caries/microbiology ; }, abstract = {UNLABELLED: Microorganisms resist fluoride toxicity using fluoride export proteins from one of several different molecular families. Cariogenic species Streptococcus mutans and Candida albicans extrude intracellular fluoride using a CLC[F] F[-]/H[+] antiporter and FEX fluoride channel, respectively, whereas oral commensal eubacteria, such as Streptococcus gordonii, export fluoride using a Fluc fluoride channel. In this work, we examine how genetic knockout of fluoride export impacts pathogen fitness in single-species and three-species dental biofilm models. For biofilms generated using S. mutans with the genetic knockout of the CLC[F] transporter, exposure to low fluoride concentrations decreased S. mutans counts, synergistically reduced the populations of C. albicans, increased the relative proportion of oral commensal S. gordonii, and reduced properties associated with biofilm pathogenicity, including acid production and hydroxyapatite dissolution. Biofilms prepared with C. albicans with genetic knockout of the FEX channel also exhibited reduced fitness in the presence of fluoride but to a lesser degree. Imaging studies indicate that S. mutans is highly sensitive to fluoride, with the knockout strain undergoing complete lysis when exposed to low fluoride for a moderate amount of time. Biochemical purification of the S. mutans CLC[F] transporter and functional reconstitution establishes that the functional protein is a dimer encoded by a single gene. Together, these findings suggest that fluoride export by oral pathogens can be targeted by specific inhibitors to restore biofilm symbiosis in dental biofilms and that S. mutans is especially susceptible to fluoride toxicity.<br><br>IMPORTANCE: Dental caries is a globally prevalent condition that occurs when pathogenic species, including Streptococcus mutans and Candida albicans, outcompete beneficial species, such as Streptococcus gordonii, in the dental biofilm. Fluoride is routinely used in oral hygiene to prevent dental caries. Fluoride also has antimicrobial properties, although most microbes possess fluoride exporters to resist its toxicity. This work shows that sensitization of cariogenic species S. mutans and C. albicans to fluoride by genetic knockout of fluoride exporters alters the microbial composition and pathogenic properties of dental biofilms. These results suggest that the development of drugs that inhibit fluoride exporters could potentiate the anticaries effect of fluoride in over-the-counter products like toothpaste and mouth rinses. This is a novel strategy to treat dental caries.}, }
@article {pmid38622845, year = {2024}, author = {Priyadarshini, E and Kumar, R and Balakrishnan, K and Pandit, S and Kumar, R and Jha, NK and Gupta, PK}, title = {Biofilm Inhibition on Medical Devices and Implants Using Carbon Dots: An Updated Review.}, journal = {ACS applied bio materials}, volume = {7}, number = {5}, pages = {2604-2619}, doi = {10.1021/acsabm.4c00024}, pmid = {38622845}, issn = {2576-6422}, mesh = {*Biofilms/drug effects ; *Carbon/chemistry/pharmacology ; *Anti-Bacterial Agents/pharmacology/chemistry ; Humans ; Prostheses and Implants ; Biocompatible Materials/chemistry/pharmacology ; Quantum Dots/chemistry ; Particle Size ; Microbial Sensitivity Tests ; Materials Testing ; Equipment and Supplies/microbiology ; }, abstract = {Biofilms are an intricate community of microbes that colonize solid surfaces, communicating via a quorum-sensing mechanism. These microbial aggregates secrete exopolysaccharides facilitating adhesion and conferring resistance to drugs and antimicrobial agents. The escalating global concern over biofilm-related infections on medical devices underscores the severe threat to human health. Carbon dots (CDs) have emerged as a promising substrate to combat microbes and disrupt biofilm matrices. Their numerous advantages such as facile surface functionalization and specific antimicrobial properties, position them as innovative anti-biofilm agents. Due to their minuscule size, CDs can penetrate microbial cells, inhibiting growth via cytoplasmic leakage, reactive oxygen species (ROS) generation, and genetic material fragmentation. Research has demonstrated the efficacy of CDs in inhibiting biofilms formed by key pathogenic bacteria such as Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. Consequently, the development of CD-based coatings and hydrogels holds promise for eradicating biofilm formation, thereby enhancing treatment efficacy, reducing clinical expenses, and minimizing the need for implant revision surgeries. This review provides insights into the mechanisms of biofilm formation on implants, surveys major biofilm-forming pathogens and associated infections, and specifically highlights the anti-biofilm properties of CDs emphasizing their potential as coatings on medical implants.}, }
@article {pmid38621525, year = {2024}, author = {Sampaio, C and Méndez, DAC and Buzalaf, MAR and Pessan, JP and Cruvinel, T}, title = {Arginine and sodium fluoride affect the microbial composition and reduce biofilm metabolism and enamel mineral loss in an oral microcosm model.}, journal = {Journal of dentistry}, volume = {145}, number = {}, pages = {104997}, doi = {10.1016/j.jdent.2024.104997}, pmid = {38621525}, issn = {1879-176X}, mesh = {*Biofilms/drug effects ; *Arginine/pharmacology ; *Sodium Fluoride/pharmacology ; *Dental Enamel/drug effects/microbiology ; Cattle ; Animals ; *Tooth Demineralization/prevention &amp; control/microbiology ; *Cariostatic Agents/pharmacology ; *Saliva/microbiology/metabolism/drug effects ; Hydrogen-Ion Concentration ; *Microscopy, Confocal ; Microbial Viability/drug effects ; Calcium/analysis/metabolism ; Streptococcus/drug effects ; Xanthenes/pharmacology ; Colony Count, Microbial ; Oxazines/pharmacology ; }, abstract = {OBJECTIVE: To assess the effects of arginine, with or without sodium fluoride (NaF; 1,450 ppm), on saliva-derived microcosm biofilms and enamel demineralization.<br><br>METHODS: Saliva-derived biofilms were grown on bovine enamel blocks in 0.2 % sucrose-containing modified McBain medium, according to six experimental groups: control (McBain 0.2 %); 2.5 % arginine; 8 % arginine; NaF; 2.5 % arginine with NaF; and 8 % arginine with NaF. After 5 days of growth, biofilm viability was assessed by colony-forming units counting, laser scanning confocal microscopy was used to determine biofilm vitality and extracellular polysaccharide (EPS) production, while biofilm metabolism was evaluated using the resazurin assay and lactic acid quantification. Demineralization was evaluated by measuring pH in the culture medium and calcium release. Data were analyzed by Kruskal-Wallis' and Dunn's tests (p < 0.05).<br><br>RESULTS: 8 % arginine with NaF showed the strongest reduction in total streptococci and total microorganism counts, with no significant difference compared to arginine without NaF. Neither 2.5 % arginine alone nor NaF alone significantly reduced microbial counts compared to the control, although in combination, a reduction in all microbial groups was observed. Similar trends were found for biofilm vitality and EPS, and calcium released to the growth medium.<br><br>CONCLUSIONS: 8 % Arginine, with or without NaF, exhibited the strongest antimicrobial activity and reduced enamel calcium loss. Also, NaF enhanced the effects of 2.5 % arginine, yielding similar results to 8 % arginine for most parameters analyzed.<br><br>CLINICAL SIGNIFICANCE: The results provided further evidence on how arginine, with or without NaF, affects oral microcosm biofilms and enamel mineral loss.}, }
@article {pmid38621382, year = {2024}, author = {Chaudhary, K and Agrahari, B and Biswas, B and Chatterjee, N and Chaudhary, A and Kumar, A and Sonker, H and Dewan, S and Saxena, D and Akhir, A and Malhotra, N and Chopra, S and Misra, S and Matheswaran, S and Singh, RG}, title = {Pyridine-2,6-Dicarboxamide Proligands and their Cu(II)/Zn(II) Complexes Targeting Staphylococcus Aureus for the Attenuation of In Vivo Dental Biofilm.}, journal = {Advanced healthcare materials}, volume = {13}, number = {20}, pages = {e2400378}, doi = {10.1002/adhm.202400378}, pmid = {38621382}, issn = {2192-2659}, support = {2021435//DST SERB/ ; 2019295//INSPIRE Faculty Research Grant/ ; 2300572//Prime Minister Research Grant/ ; //TTI Division of DST/ ; }, mesh = {*Biofilms/drug effects ; Animals ; *Staphylococcus aureus/drug effects ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Zinc/chemistry/pharmacology ; *Copper/chemistry/pharmacology ; *Microbial Sensitivity Tests ; Rats ; *Pyridines/chemistry/pharmacology ; Coordination Complexes/chemistry/pharmacology ; Staphylococcal Infections/drug therapy ; Ligands ; Rats, Sprague-Dawley ; }, abstract = {In the pursuit to combat stubborn bacterial infections, particularly those stemming from gram-positive bacteria, this study is an attempt to craft a precision-driven platform characterized by unparalleled selectivity, specificity, and synergistic antimicrobial mechanisms. Leveraging remarkable potential of metalloantibiotics in antimicrobial applications, herein, this work rationally designs, synthesizes, and characterizes a new library of Pyridine-2,6-dicarboxamide ligands and their corresponding transition metal Cu(II)/Zn(II) complexes. The lead compound L[11] demonstrates robust antibacterial properties against Staphylococcus aureus (Minimum Inhibitory Concentration (MIC) = 2-16 µg mL[-1]), methicillin and vancomycin-resistant S. aureus (MIC = 2-4 µg mL[-1]) and exhibit superior antibacterial activity when compared to FDA-approved vancomycin, the drug of last resort. Additionally, the compound exhibits notable antimicrobial efficacy against resistant enterococcus strains (MIC = 2-8 µg mL[-1]). To unravel mechanistic profile, advanced imaging techniques including SEM and AFM are harnessed, collectively suggesting a mechanistic pathway involving cell wall disruption. Live/dead fluorescence studies further confirm efficacy of L[11] and its complexes against S. aureus membranes. This translational exploration extends to a rat model, indicating promising in vivo therapeutic potential. Thus, this comprehensive research initiative has capabilities to transcends the confines of this laboratory, heralding a pivotal step toward combatting antibiotic-resistant pathogens and advancing the frontiers of metalloantibiotics-based therapy with a profound clinical implication.}, }
@article {pmid38621130, year = {2024}, author = {Postek, W and Staśkiewicz, K and Lilja, E and Wacław, B}, title = {Substrate geometry affects population dynamics in a bacterial biofilm.}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, volume = {121}, number = {17}, pages = {e2315361121}, pmid = {38621130}, issn = {1091-6490}, support = {UMO-2019/02/H/NZ6/00003//Narodowe Centrum Nauki (NCN)/ ; PPN/PPO/2019/1/ 00030 /U/0001//Narodowa Agencja Wymiany Akademickiej (NAWA)/ ; PPN/BEK/2020/1/00333/U/00001//Narodowa Agencja Wymiany Akademickiej (NAWA)/ ; 069.2021//Fundacja na rzecz Nauki Polskiej (FNP)/ ; }, mesh = {*Biofilms ; *Anti-Bacterial Agents ; Bacteria ; Rifampin/pharmacology ; Escherichia coli/genetics ; Bacterial Adhesion ; }, abstract = {Biofilms inhabit a range of environments, such as dental plaques or soil micropores, often characterized by noneven surfaces. However, the impact of surface irregularities on the population dynamics of biofilms remains elusive, as most experiments are conducted on flat surfaces. Here, we show that the shape of the surface on which a biofilm grows influences genetic drift and selection within the biofilm. We culture Escherichia coli biofilms in microwells with a corrugated bottom surface and observe the emergence of clonal sectors whose size corresponds to that of the corrugations, despite no physical barrier separating different areas of the biofilm. The sectors are remarkably stable and do not invade each other; we attribute this stability to the characteristics of the velocity field within the biofilm, which hinders mixing and clonal expansion. A microscopically detailed computer model fully reproduces these findings and highlights the role of mechanical interactions such as adhesion and friction in microbial evolution. The model also predicts clonal expansion to be limited even for clones with a significant growth advantage-a finding which we confirm experimentally using a mixture of antibiotic-sensitive and antibiotic-resistant mutants in the presence of sublethal concentrations of the antibiotic rifampicin. The strong suppression of selection contrasts sharply with the behavior seen in range expansion experiments in bacterial colonies grown on agar. Our results show that biofilm population dynamics can be affected by patterning the surface and demonstrate how a better understanding of the physics of bacterial growth can be used to control microbial evolution.}, }
@article {pmid38619862, year = {2024}, author = {Tian, Y and Zhong, F and Shang, N and Yu, H and Mao, D and Huang, X}, title = {Maize Root Exudates Promote Bacillus sp. Za Detoxification of Diphenyl Ether Herbicides by Enhancing Colonization and Biofilm Formation.}, journal = {Molecular plant-microbe interactions : MPMI}, volume = {37}, number = {7}, pages = {552-560}, doi = {10.1094/MPMI-02-24-0020-R}, pmid = {38619862}, issn = {0894-0282}, mesh = {*Zea mays/microbiology ; *Biofilms ; *Bacillus/metabolism/physiology ; *Herbicides/metabolism ; *Plant Roots/microbiology ; *Rhizosphere ; Biodegradation, Environmental ; Plant Exudates/metabolism ; Phenyl Ethers/metabolism ; Soil Pollutants/metabolism ; }, abstract = {Diphenyl ether herbicides are extensively utilized in agricultural systems, but their residues threaten the health of sensitive rotation crops. Functional microbial strains can degrade diphenyl ether herbicides in the rhizosphere of crops, facilitating the restoration of a healthy agricultural environment. However, the interplay between microorganisms and plants in diphenyl ether herbicides degradation remains unclear. Thus, the herbicide-degrading strain Bacillus sp. Za and the sensitive crop, maize, were employed to uncover the interaction mechanism. The degradation of diphenyl ether herbicides by strain Bacillus sp. Za was promoted by root exudates. The strain induced root exudate re-secretion in diphenyl ether herbicide-polluted maize. We further showed that root exudates enhanced the rhizosphere colonization and the biofilm biomass of strain Za, augmenting its capacity to degrade diphenyl ether herbicide. Root exudates regulated gene fliZ, which is pivotal in biofilm formation. Wild-type strain Za significantly reduced herbicide toxicity to maize compared to the ZaΔfliZ mutant. Moreover, root exudates promoted strain Za growth and chemotaxis, which was related to biofilm formation. This mutualistic relationship between the microorganisms and the plants demonstrates the significance of plant-microbe interactions in shaping diphenyl ether herbicide degradation in rhizosphere soils. [Formula: see text] The author(s) have dedicated the work to the public domain under the Creative Commons CC0 "No Rights Reserved" license by waiving all of his or her rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law, 2024.}, }
@article {pmid38619794, year = {2024}, author = {Van Holm, W and Zayed, N and Lauwens, K and Saghi, M and Axelsson, J and Aktan, MK and Braem, A and Simoens, K and Vanbrabant, L and Proost, P and Van Holm, B and Maes, P and Boon, N and Bernaerts, K and Teughels, W}, title = {Oral Biofilm Composition, Dissemination to Keratinocytes, and Inflammatory Attenuation Depend on Probiotic and Synbiotic Strain Specificity.}, journal = {Probiotics and antimicrobial proteins}, volume = {}, number = {}, pages = {}, pmid = {38619794}, issn = {1867-1314}, support = {C24/17/086//KU Leuven/ ; C16/17/010//KU Leuven/ ; C16/17/010//KU Leuven/ ; C24/17/086//KU Leuven/ ; G091218N//Fonds Wetenschappelijk Onderzoek/ ; G091218N//Fonds Wetenschappelijk Onderzoek/ ; }, abstract = {Several inflammatory diseases are characterized by a disruption in the equilibrium between the host and its microbiome. Due to the increase in resistance, the use of antibiotics for the widespread, nonspecific killing of microorganisms is at risk. Pro-microbial approaches focused on stimulating or introducing beneficial species antagonistic toward pathobionts may be a viable alternative for restoring the host-microbiome equilibrium. Unfortunately, not all potential probiotic or synbiotic species and even subspecies (to strain level) are equally effective for the designated pathology, leading to conflicting accounts of their efficacy. To assess the extent of these species- and strain-specific effects, 13 probiotic candidates were evaluated for their probiotic and synbiotic potential with glycerol on in vitro oral biofilms, dissemination from biofilms to keratinocytes, and anti-inflammatory activity. Species- and strain-specific effects and efficacies were observed in how they functioned as probiotics or synbiotics by influencing oral pathobionts and commensals within biofilms and affected the dissemination of pathobionts to keratinocytes, ranging from ineffective strains to strains that reduced pathobionts by 3 + log. In addition, a minority of the candidates exhibited the ability to mitigate the inflammatory response of LPS-stimulated monocytes. For a comprehensive assessment of probiotic therapy for oral health, a judicious selection of fully characterized probiotic strains that are specifically tailored to the designated pathology is required. This approach aims to challenge the prevailing perception of probiotics, shifting the focus away from "form over function." Rather than using unproven, hypothetical probiotic strains from known genera or species, one should choose strains that are actually functional in resolving the desired pathology before labelling them probiotics.}, }
@article {pmid38618300, year = {2024}, author = {Berk Ergun, &#x15e; and Has, EG and Akçelik, N and Akçelik, M}, title = {Characteristics of Bacterial Biofilm Formation in Nasolacrimal Silicone Tubes Post-dacryocystorhinostomy.}, journal = {Cureus}, volume = {16}, number = {3}, pages = {e56112}, pmid = {38618300}, issn = {2168-8184}, abstract = {PURPOSE: To examine the biofilm formation characteristics of bacteria identified at the genus level in samples obtained from silicone tubes after dacryocystorhinostomy surgery.<br><br>METHODS: In the study involving consecutive patients who underwent dacryocystorhinostomy surgery at Ankara Bilkent City Hospital and whose silicone tubes were removed six months after surgery, between January 2023 and May 2023; the tubes were placed in glycerol-PBS (phosphate buffered saline) solution and cultured on descriptive selective media at the genus level. The biofilm-forming properties of the obtained isolates were examined in solid-air and liquid-air interphases. Salmonella Typhimurium ATCC SL1344 strain was used as the control bacterium.<br><br>RESULTS: As a result of the analysis of the samples taken from the patients, Pseudomonas spp. was identified in three of the samples, Staphylococcus spp. in five of the samples, and Streptococcus spp. in one of the samples. Among these samples, except for the bacteria identified in samples one and five, the rest were found to be strong biofilm producers. In all strong biofilm producers, the maximum biofilm production time was determined as 72 h and the incubation temperature was 37&#xb0;C. The presence of cellulose and amyloid proteins in biofilm matrix structures is identified. Swimming and swarming motilities were observed in all bacterial samples.<br><br>CONCLUSION: Since biofilms are considered potential factors in the pathogenesis of infectious and inflammatory diseases, they are a subject that needs to be thoroughly investigated. In our study, although there were no clinical infections in any of the patients, biofilm formation was detected in the patient samples. The fact that the bacteria exhibited moderate to strong biofilm formation characteristics suggests that these microorganisms could be persistent infectious agents.}, }
@article {pmid38616595, year = {2024}, author = {Shah, PK and Bhandari, N and Tamang, B and Joshi, RD}, title = {Antibiotic Susceptibility and Biofilm Production among Coagulase Negative Staphylococci Isolated from Clinical Samples at Tertiary Care Hospital.}, journal = {Journal of Nepal Health Research Council}, volume = {21}, number = {4}, pages = {636-641}, doi = {10.33314/jnhrc.v21i4.4894}, pmid = {38616595}, issn = {1999-6217}, mesh = {Female ; Humans ; *Coagulase ; Cross-Sectional Studies ; Tertiary Care Centers ; Nepal ; *Staphylococcus ; Anti-Bacterial Agents/pharmacology ; Biofilms ; }, abstract = {BACKGROUND: Coagulase Negative Staphylococci have been widely associated with medical device implant treatment and immune-compromised patients. Despite having increasing interest in Coagulase Negative Staphylococci, few studies from Nepal have reported the association of these organisms with urinary tract infections, conjunctivitis, high vaginal swabs, and cerebrospinal fluid. This study was carried out to determine antibiotic susceptibility pattern and biofilm production among Coagulase Negative Staphylococci isolated from clinical samples at tertiary care hospital.<br><br>METHODS: This study was a hospital based cross-sectional study in which 3690 clinical samples were included. Isolation and identification of isolates was done following standard microbiological protocol. Coagulase Negative Staphylococci were identified phenotypically on the basis of gram staining, slide and tube coagulase test and by various sugar fermentation tests. Antibiotic susceptibility test was done following Kirby Bauer disk diffusion method (Clinical and Laboratory Standards Institute 2020). Biofilm production was determined by Tissue Culture Plate technique.<br><br>RESULTS: A total of 113 isolates of Coagulase Negative Staphylococci were detected. Among them S. epidermidis (45.1%), S. saprophyticus (23.9%), S. haemolyticus (16.8%), S. hominis (5.3%), S. capitis (2.7%), -----S. cohini (1.8%), S. lugdunensis (1.8%) and S. sciuri (2.7%) were identified phenotypically. All isolates were found to be resistant against Ampicillin and 111 (98.2%) were sensitive against Linezolid.23.9% of CoNS were strong biofilm producers, 19.5% moderate and 56.6 % were non/weak biofilm producers.<br><br>CONCLUSIONS: It requires susceptibility test for prescribing antibiotics against Coagulase Negative Staphylococci in hospital and the misuse of antibiotics should be prevented.}, }
@article {pmid38616221, year = {2024}, author = {Srivastava, A and Verma, N and Kumar, V and Apoorva, P and Agarwal, V}, title = {Biofilm inhibition/eradication: exploring strategies and confronting challenges in combatting biofilm.}, journal = {Archives of microbiology}, volume = {206}, number = {5}, pages = {212}, pmid = {38616221}, issn = {1432-072X}, mesh = {Animals ; Humans ; *Biofilms ; Quorum Sensing ; Anti-Bacterial Agents/pharmacology ; *Bacteriophages ; Extracellular Matrix ; }, abstract = {Biofilms are complex communities of microorganisms enclosed in a self-produced extracellular matrix, posing a significant threat to different sectors, including healthcare and industry. This review provides an overview of the challenges faced due to biofilm formation and different novel strategies that can combat biofilm formation. Bacteria inside the biofilm exhibit increased resistance against different antimicrobial agents, including conventional antibiotics, which can lead to severe problems in livestock and animals, including humans. In addition, biofilm formation also imposes heavy economic pressure on industries. Hence it becomes necessary to explore newer alternatives to eradicate biofilms effectively without applying selection pressure on the bacteria. Excessive usage of antibiotics may also lead to an increase in the number of resistant strains as bacteria employ an advanced antimicrobial resistance mechanism. This review provides insight into multifaceted technologies like quorum sensing inhibition, enzymes, antimicrobial peptides, bacteriophage, phytocompounds, and nanotechnology to neutralize biofilms without developing antimicrobial resistance (AMR). Furthermore, it will pave the way for developing newer therapeutic agents to deal with biofilms more efficiently.}, }
@article {pmid38615826, year = {2024}, author = {Pereira, ACC and Aguiar, APS and Barbosa, VL and Régis, JR and Miyazima, EM and Araujo, LMP and Dantas, LO and Mayer, MPA and Andrade, FB and Karygianni, L and Pinheiro, ET}, title = {Enhancing Antibiotic Efficacy in Regenerative Endodontics by Improving Biofilm Susceptibility.}, journal = {Journal of endodontics}, volume = {50}, number = {7}, pages = {962-965}, doi = {10.1016/j.joen.2024.04.004}, pmid = {38615826}, issn = {1878-3554}, mesh = {*Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology ; *Regenerative Endodontics/methods ; *Nisin/pharmacology ; *Metronidazole/pharmacology ; Humans ; *Ciprofloxacin/pharmacology ; Minocycline/pharmacology ; Microbial Sensitivity Tests ; Drug Combinations ; }, abstract = {INTRODUCTION: Various strategies have been researched to enhance the susceptibility of biofilms, given their tolerance to antibiotics. This study evaluated the effect of the anti-microbial peptide nisin in association with antibiotics used in regenerative endodontics, exploring different treatment times and biofilm growth conditions.<br><br>METHODS: A mixture of 10 bacterial species was cultivated on dentin specimens anaerobically for 21&#xa0;days. Biofilms were treated with 1&#xa0;mL of high-purity nisin Z (nisin ZP, 200&#xa0;&#x3bc;g/mL) and a triple antibiotic mixture (TAP: ciprofloxacin&#xa0;+&#xa0;metronidazole&#xa0;+&#xa0;minocycline, 5&#xa0;mg/mL), alone or in combination. The effectiveness of antimicrobial agents was assessed after 1 and 7 days. During the 7-day period, biofilms were treated under 2 conditions: a single dose in a nutrient-depleted setting (ie, no replenishment of growth medium) and multiple doses in a nutrient-rich environment (ie, renewal of medium and antimicrobial agents every 48&#xa0;h). After treatments, biofilm cells were dispersed, and total colony-forming units were counted.<br><br>RESULTS: After 1 d-treatment, nisin&#xa0;ZP&#xa0;+&#xa0;TAP resulted in 2-log cell reduction compared to TAP alone (P&#xa0;<&#xa0;.05). After 7&#xa0;d-treatment with a single dose, nisin ZP&#xa0;+&#xa0;TAP and TAP reduced bacteria to nonculturable levels (P&#xa0;<&#xa0;.05), whereas repeated antimicrobial doses did not eliminate bacteria in a nutrient-rich environment. No bacterial reduction was observed with nisin ZP alone in any treatment time.<br><br>CONCLUSIONS: The additional use of nisin improved the TAP activity only after a short exposure time. Longer exposure to TAP or nisin&#xa0;+&#xa0;TAP in a nutrient-deprived environment effectively eliminated biofilms.}, }
@article {pmid38614413, year = {2024}, author = {Ali, A and Riaz, S}, title = {Emerging threats of high biofilm formation and antibiotic resistance in clinical methicillin-resistant Staphylococcus aureus (MRSA) isolates from Pakistan.}, journal = {Infection, genetics and evolution : journal of molecular epidemiology and evolutionary genetics in infectious diseases}, volume = {121}, number = {}, pages = {105592}, doi = {10.1016/j.meegid.2024.105592}, pmid = {38614413}, issn = {1567-7257}, mesh = {*Biofilms/drug effects/growth &amp; development ; Pakistan/epidemiology ; *Methicillin-Resistant Staphylococcus aureus/drug effects/genetics/isolation &amp; purification ; Humans ; *Staphylococcal Infections/microbiology/epidemiology ; *Anti-Bacterial Agents/pharmacology ; *Microbial Sensitivity Tests ; Phylogeny ; Drug Resistance, Bacterial ; Bacterial Proteins/genetics ; RNA, Ribosomal, 16S/genetics ; }, abstract = {OBJECTIVES: This multicenter study, conducted from a One Health perspective, aimed to comprehensively examine the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) infections and their biofilm-forming capabilities in Pakistan. Phylogenetic analysis of the study isolates was also performed.<br><br>METHODS: A total of 150 MRSA isolates were screened from various clinical samples using Cefoxitin antibiotic discs. Genotypic confirmation was conducted through mecA, S. aureus-specific nuc, and 16S rRNA genes. Biofilm formation was assessed using Congo red agar (CRA) and slime layer quantification methods. The intercellular adhesion (ica) operon genes, specifically icaA and icaD, were detected. Phylogenetic analysis utilized the 16S rRNA sequences. Statistical associations between various parameters were determined using chi-square analysis.<br><br>RESULTS: The presence of the mecA gene was observed in 131 out of 150 isolates (87.3%). CRA identified 28% and 40% of isolates as strong and moderate biofilm producers, respectively, while 9.3% were classified as non-biofilm producers. The slime layer assay exhibited higher sensitivity, classifying only 4.7% of isolates as non-biofilm producers. Biofilm-forming genes icaA and icaD were detected in 85.3% and 86.7% of the isolates, respectively. Antibiotic resistance was more prevalent among biofilm-forming isolates, particularly against ciprofloxacin, levofloxacin, erythromycin, trimethoprim-sulfamethoxazole, and fosfomycin. Ceftaroline demonstrated efficacy irrespective of biofilm-forming abilities. Conversely, non-biofilm producers exhibited complete susceptibility to clarithromycin and tigecycline.<br><br>CONCLUSIONS: Clinical MRSA strains exhibit a substantial potential for biofilm formation, contributing to a resistant phenotype. Routine antibiotic testing in clinical settings that overlook the biofilm aspect may lead to the failure of empiric antibiotic therapy.}, }
@article {pmid38614333, year = {2024}, author = {Buakaew, T and Ratanatamskul, C}, title = {Unveiling the influence of microaeration and sludge recirculation on enhancement of pharmaceutical removal and microbial community change of the novel anaerobic baffled biofilm - membrane bioreactor in treating building wastewater.}, journal = {The Science of the total environment}, volume = {927}, number = {}, pages = {172420}, doi = {10.1016/j.scitotenv.2024.172420}, pmid = {38614333}, issn = {1879-1026}, mesh = {*Bioreactors/microbiology ; *Biofilms ; *Waste Disposal, Fluid/methods ; *Water Pollutants, Chemical/metabolism/analysis ; *Wastewater ; *Sewage/microbiology ; Anaerobiosis ; Microbiota ; Pharmaceutical Preparations/metabolism ; Sulfamethoxazole ; }, abstract = {This research aims to conduct a comparative investigation of the role played by microaeration and sludge recirculation in the novel anaerobic baffled biofilm-membrane bioreactor (AnBB-MBR) for enhancing pharmaceutical removal from building wastewater. Three AnBB-MBRs - R1: AnBB-MBR, R2: AnBB-MBR with microaeration and R3: AnBB-MBR with microaeration and sludge recirculation - were operated simultaneously to remove Ciprofloxacin (CIP), Caffeine (CAF), Sulfamethoxazole (SMX) and Diclofenac (DCF) from real building wastewater at the hydraulic retention time (HRT) of 30 h for 115 days. From the removal profiles of the targeted pharmaceuticals in the AnBB-MBRs, it was found that the fixed-film compartment (C1) could significantly reduce the targeted pharmaceuticals. The remaining pharmaceuticals were further removed with the microaeration compartment. R2 exhibited the utmost removal efficiency for CIP (78.0 %) and DCF (40.8 %), while SMX was removed most successfully by R3 (microaeration with sludge recirculation) at 91.3 %, followed by microaeration in R2 (88.5 %). For CAF, it was easily removed by all AnBB-MBR systems (>90 %). The removal mechanisms indicate that the microaeration in R2 facilitated the adsorption of CIP onto microaerobic biomass, while the enhanced biodegradation of CAF, SMX and DCF was confirmed by batch biotransformation kinetics and the adsorption isotherms of the targeted pharmaceuticals. The microbial groups involved in biodegradation of the targeted compounds under microaeration were identified as nitrogen removal microbials (Nitrosomonas, Nitrospira, Thiobacillus, and Denitratisoma) and methanotrophs (Methylosarcina, Methylocaldum, and Methylocystis). Overall, explication of the integration of AnBB-MBR with microaeration (R2) confirmed it as a prospective technology for pharmaceutical removal from building wastewater due to its energy-efficient approach characterized by minimal aeration supply.}, }
@article {pmid38613837, year = {2024}, author = {Quispe Haro, JJ and Chen, F and Los, R and Shi, S and Sun, W and Chen, Y and Idema, T and Wegner, SV}, title = {Optogenetic Control of Bacterial Cell-Cell Adhesion Dynamics: Unraveling the Influence on Biofilm Architecture and Functionality.}, journal = {Advanced science (Weinheim, Baden-Wurttemberg, Germany)}, volume = {11}, number = {23}, pages = {e2310079}, pmid = {38613837}, issn = {2198-3844}, support = {DFG WE 5745/2-2//Deutsche Forschungsgemeinschaft/ ; 22208157//National Natural Science Foundation of China/ ; }, mesh = {*Biofilms/growth &amp; development ; *Bacterial Adhesion/physiology ; *Optogenetics/methods ; Quorum Sensing/physiology ; }, abstract = {The transition of bacteria from an individualistic to a biofilm lifestyle profoundly alters their biology. During biofilm development, the bacterial cell-cell adhesions are a major determinant of initial microcolonies, which serve as kernels for the subsequent microscopic and mesoscopic structure of the biofilm, and determine the resulting functionality. In this study, the significance of bacterial cell-cell adhesion dynamics on bacterial aggregation and biofilm maturation is elucidated. Using photoswitchable adhesins between bacteria, modifying the dynamics of bacterial cell-cell adhesions with periodic dark-light cycles is systematic. Dynamic cell-cell adhesions with liquid-like behavior improve bacterial aggregation and produce more compact microcolonies than static adhesions with solid-like behavior in both experiments and individual-based simulations. Consequently, dynamic cell-cell adhesions give rise to earlier quorum sensing activation, better intermixing of different bacterial populations, improved biofilm maturation, changes in the growth of cocultures, and higher yields in fermentation. The here presented approach of tuning bacterial cell-cell adhesion dynamics opens the door for regulating the structure and function of biofilms and cocultures with potential biotechnological applications.}, }
@article {pmid38613443, year = {2024}, author = {Hajimohammadi, S and Momtaz, H and Tajbakhsh, E}, title = {Fabrication and antimicrobial properties of novel meropenem-honey encapsulated chitosan nanoparticles against multiresistant and biofilm-forming Staphylococcus aureus as a new antimicrobial agent.}, journal = {Veterinary medicine and science}, volume = {10}, number = {3}, pages = {e1440}, pmid = {38613443}, issn = {2053-1095}, support = {//Islamic Azad University, Shahrekord Branch/ ; }, mesh = {Animals ; Humans ; Meropenem/pharmacology ; Staphylococcus aureus ; Anti-Bacterial Agents/pharmacology ; *Chitosan/pharmacology ; *Methicillin-Resistant Staphylococcus aureus ; HEK293 Cells ; *Honey ; Gram-Negative Bacteria ; Gram-Positive Bacteria ; *Anti-Infective Agents ; *Staphylococcal Infections/veterinary ; *Nanoparticles ; Biofilms ; }, abstract = {BACKGROUND: Honey exhibits a broad spectrum of antibacterial activity against Gram-positive and Gram-negative bacteria, including methicillin-resistant Staphylococcus aureus (MRSA) ones. Chitosan (Cs) is a mucoadhesive polymer that also has antibacterial properties. Special attention has been paid to the design of polymeric nanoparticles (NPs) as new nano drug delivery systems to overcome bacterial resistance and its problems.<br><br>OBJECTIVES: The aim of the present study is to synthesize Cs-meropenem NPs with/without honey as an antibiofilm and antibacterial agent to inhibit Staphylococcus aureus.<br><br>METHODS: This study synthesized meropenem and honey-loaded Cs nanogels and subsequently characterized them by Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform Infrared Spectroscopy (FTIR), and DLS-zeta potential. Using the broth microdilution and crystal violet assays, the antibacterial and antibiofilm activity of meropenem and honey-loaded Cs nanogel, free meropenem, free honey, and free Cs NPs were investigated in vitro against MRSA strains. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) was also used to test the cytotoxicity of several Cs-NPs compound against the HEK-293 regular cell line.<br><br>RESULTS: The average size of meropenem and honey-Cs-NPs was reported to be 119.885&#xa0;nm, and encapsulation efficiency was 88.33 &#xb1; 0.97 with stability up to 60 days at 4&#xb0;C. The NPs showed enhanced antibiofilm efficacy against S. aureus at sub-minimum inhibitory concentrations. Additionally, the cytotoxicity of meropenem and honey-encapsulated Cs against the HEK-293 normal cell line was insignificant.<br><br>CONCLUSIONS: Our findings suggested that meropenem and honey-Cs-NPs might be potential antibacterial and antibiofilm materials.}, }
@article {pmid38612793, year = {2024}, author = {Donati, L and Casagrande Pierantoni, D and Conti, A and Calzoni, E and Corte, L and Santi, C and Rosati, O and Cardinali, G and Emiliani, C}, title = {Water Extracts from Industrial Hemp Waste Inhibit the Adhesion and Development of Candida Biofilm and Showed Antioxidant Activity on HT-29 Colon Cancer Cells.}, journal = {International journal of molecular sciences}, volume = {25}, number = {7}, pages = {}, pmid = {38612793}, issn = {1422-0067}, support = {J91B21003350006//Italian Ministry of University and Research (MIUR)/ ; }, mesh = {Candida ; *Cannabis ; Antioxidants/pharmacology ; *Colonic Neoplasms ; Tissue Adhesions ; Biofilms ; Industrial Waste ; *Anti-Infective Agents ; }, abstract = {The evolution of regulatory perspectives regarding the health and nutritional properties of industrial hemp-based products (Cannabis sativa L.) has pushed research to focus on the development of new methods for both the extraction and formulation of the bioactive compounds present in hemp extracts. While the psychoactive and medicinal properties of hemp-derived cannabinoid extracts are well known, much less has been investigated on the functional and antimicrobial properties of hemp extracts. Within the hemp value chain, various agricultural wastes and by-products are generated. These materials can be valorised through eco-innovations, ultimately promoting sustainable economic development. In this study, we explored the use of waste from industrial light cannabis production for the extraction of bioactive compounds without the addition of chemicals. The five extracts obtained were tested for their antimicrobial activity on both planktonic and sessile cells of pathogenic strains of the Candida albicans, Candida parapsilosis, and Candida tropicalis species and for their antioxidant activity on HT-29 colon cancer cells under oxidative stress. Our results demonstrated that these extracts display interesting properties both as antioxidants and in hindering the development of fungal biofilm, paving the way for further investigations into the sustainable valorisation of hemp waste for different biomedical applications.}, }
@article {pmid38612411, year = {2024}, author = {Chen, Y and Gao, Y and Li, Y and Yin, J}, title = {Anti-Biofilm Activity of Assamsaponin A, Theasaponin E1, and Theasaponin E2 against Candida albicans.}, journal = {International journal of molecular sciences}, volume = {25}, number = {7}, pages = {}, pmid = {38612411}, issn = {1422-0067}, support = {CARS-19//China Agriculture Research System of MOF and MARA/ ; CAAS-ASTIP-TRI//the Innovation Project for Chinese Academy of Agricultural Sciences/ ; }, mesh = {*Candida albicans ; *Saponins/pharmacology ; Biofilms ; Tea ; Oleanolic Acid/*analogs &amp; derivatives ; }, abstract = {Biofilm formation plays a crucial role in the pathogenesis of Candida albicans and is significantly associated with resistance to antifungal agents. Tea seed saponins, a class of non-ionic triterpenes, have been proven to have fungicidal effects on planktonic C. albicans. However, their anti-biofilm activity and mechanism of action against C. albicans remain unclear. In this study, the effects of three Camellia sinensis seed saponin monomers, namely, theasaponin E1 (TE1), theasaponin E2 (TE2), and assamsaponin A (ASA), on the metabolism, biofilm development, and expression of the virulence genes of C. albicans were evaluated. The results of the XTT reduction assay and crystal violet (CV) staining assay demonstrated that tea seed saponin monomers concentration-dependently suppressed the adhesion and biofilm formation of C. albicans and were able to eradicate mature biofilms. The compounds were in the following order in terms of their inhibitory effects: ASA > TE1 > TE2. The mechanisms were associated with reductions in multiple crucial virulence factors, including cell surface hydrophobicity (CSH), adhesion ability, hyphal morphology conversion, and phospholipase activity. It was further demonstrated through qRT-PCR analysis that the anti-biofilm activity of ASA and TE1 against C. albicans was attributed to the inhibition of RAS1 activation, which consequently suppressed the cAMP-PKA and MAPK signaling pathways. Conversely, TE2 appeared to regulate the morphological turnover and hyphal growth of C. albicans via a pathway that was independent of RAS1. These findings suggest that tea seed saponin monomers are promising innovative agents against C. albicans.}, }
@article {pmid38612117, year = {2024}, author = {Santosaningsih, D and Mulyastuti, Y and Poejiani, S and Putri, RF and Dewi, L and Arifani, H and Ni'mah, YL and Baktir, A}, title = {The Biofilm Inhibition Properties of Glucosamine Gold Nanoparticles in Combination with Meropenem against Pseudomonas aeruginosa on the Endotracheal Tube: A Model of Biofilm-Related Ventilator-Associated Pneumonia.}, journal = {Materials (Basel, Switzerland)}, volume = {17}, number = {7}, pages = {}, pmid = {38612117}, issn = {1996-1944}, support = {801.12/UN10.C10/TU/2023//University of Brawijaya/ ; }, abstract = {Biofilm-related infections play a significant role in the development and persistence of ventilator-associated pneumonia. Pseudomonas aeruginosa (P. aeruginosa) frequently causes biofilm-related infections associated with ventilator tubing. Glucosamine gold nanoparticles (AuNPs) may exhibit antibiofilm properties; however, more studies, including combinatorial therapy with antibiotics, are needed to explore their potential applications in clinical settings. This study aims to investigate the biofilm inhibition properties of glucosamine AuNPs in combination with meropenem against P. aeruginosa ATCC 9027 on the endotracheal tube. A biofilm inhibition assay of glucosamine AuNPs at 0.02 mg/mL, both singly and in combination with meropenem at 1 mg/mL, was carried out against P. aeruginosa ATCC 9027 on an endotracheal tube using the tissue culture plate method. Scanning electron microscopy was performed for visualization. Glucosamine AuNPs at 0.02 mg/mL combined with meropenem at 1 mg/mL showed greater biofilm inhibition (72%) on the endotracheal tube than glucosamine nanoparticles at 0.02 mg/mL alone (26%) (p = 0.001). The scanning electron microscopic visualization revealed that the untreated P. aeruginosa biofilm was denser than the glucosamine nanoparticles-treated biofilm, whether combined with meropenem or using glucosamine nanoparticles alone. The combination of glucosamine AuNPs and meropenem may have the synergistic effect of inhibiting biofilm production of P. aeruginosa on the endotracheal tubes of patients with mechanical ventilation. Conducting additional experiments to explore the impact of combining glucosamine-coated gold nanoparticles (AuNPs) with meropenem on the inhibition of biofilm production by clinical P. aeruginosa isolates would be beneficial.}, }
@article {pmid38611989, year = {2024}, author = {Tzimas, K and Rahiotis, C and Pappa, E}, title = {Biofilm Formation on Hybrid, Resin-Based CAD/CAM Materials for Indirect Restorations: A Comprehensive Review.}, journal = {Materials (Basel, Switzerland)}, volume = {17}, number = {7}, pages = {}, pmid = {38611989}, issn = {1996-1944}, abstract = {Hybrid materials are a recent addition in the field of restorative dentistry for computer-aided design/computer-aided manufacturing (CAD/CAM) indirect restorations. The long-term clinical success of modern dental restorative materials is influenced by multiple factors. Among the characteristics affecting the longevity of a restoration, the mechanical properties and physicοchemical interactions are of utmost importance. While numerous researchers constantly evaluate mechanical properties, the biological background of resin-based CAD/CAM biomaterials is scarcely investigated and, therefore, less described in the literature. This review aims to analyze biofilm formation on the surfaces of novel, hybrid, resin-based CAD/CAM materials and evaluate the methodological protocols followed to assess microbial growth. It is demonstrated that the surface structure, the composition and the finishing and polishing procedures on the surface of a dental restorative material influence initial bacterial adhesion; however, most studies focus on in vitro protocols, and in vivo and/or in situ research of microbiomics in CAD/CAM restorative materials is lacking, obstructing an accurate understanding of the bioadhesion phenomenon in the oral cavity.}, }
@article {pmid38611426, year = {2024}, author = {Aydin, A and Suleymanoglu, AA and Abdramanov, A and Paulsen, P and Dumen, E}, title = {Detection of Extended Spectrum ß-Lactamase-Producing Escherichia coli with Biofilm Formation from Chicken Meat in Istanbul.}, journal = {Foods (Basel, Switzerland)}, volume = {13}, number = {7}, pages = {}, pmid = {38611426}, issn = {2304-8158}, abstract = {Antimicrobial resistance is one of the major public health problems worldwide. This study aimed to detect the presence of extended-spectrum β-lactamase-(ESBL-)producing Escherichia (E.) coli in chicken meat in Istanbul, Türkiye. Raw chicken meat samples (n = 208) were collected from different sale points and analyzed for ESBL-producing E. coli. In total, 101 (48.5%) isolates were confirmed as E. coli by PCR, of which 80/101 (79.2%) demonstrated multiple antibiotic resistance. Resistance against amoxicillin-clavulanic acid was most frequent (87.1%). Eighteen isolates (17.8%) demonstrated phenotypical ESBL resistance, as assessed by the double disc synergy test (DDST). Isolates were tested for the presence of β-lactamase genes and mobilized colistin-resistant genes. The blaTEM group was most frequently detected (97.02%), followed by blaCTX m (45.5%), blaSHV (9.9%), and blaOXA-2 (0.9%). However, mcr genes and blaNDM,blaKPC, blaVIM, and blaOXA-48 genes were not found in any isolate. E. coli strains were tested for biofilm formation in six different media [Nutrient broth, LB broth, Tryptone Soya broth (TSB), TSB containing 1% sucrose, TSB containing 0.6% yeast extract, and BHI]. Biofilm formation by E. coli isolates (44/101, 43.5%) was highest in TSB with 1% sucrose. It is worth noting that all biofilm-producing isolates were found to harbor the blaTEM-1 gene, which can indicate a high level of antibiotic resistance. This is the first report about ESBL-producing E. coli in poultry meat, the exposure of consumers in Istanbul metropolitan areas, and the ability of E. coli from this region to produce biofilms.}, }
@article {pmid38611380, year = {2024}, author = {Yang, Y and Kong, X and Niu, B and Yang, J and Chen, Q}, title = {Differences in Biofilm Formation of Listeria monocytogenes and Their Effects on Virulence and Drug Resistance of Different Strains.}, journal = {Foods (Basel, Switzerland)}, volume = {13}, number = {7}, pages = {}, pmid = {38611380}, issn = {2304-8158}, abstract = {Listeria monocytogenes is recognized as one of the primary pathogens responsible for foodborne illnesses. The ability of L. monocytogenes to form biofilms notably increases its resistance to antibiotics such as ampicillin and tetracycline, making it exceedingly difficult to eradicate. Residual bacteria within the processing environment can contaminate food products, thereby posing a significant risk to public health. In this study, we used crystal violet staining to assess the biofilm-forming capacity of seven L. monocytogenes strains and identified ATCC 19112 as the strain with the most potent biofilm-forming. Subsequent fluorescence microscopy observations revealed that the biofilm-forming capacity was markedly enhanced after two days of culture. Then, we investigated into the factors contributing to biofilm formation and demonstrated that strains with more robust extracellular polymer secretion and self-agglutination capabilities exhibited a more pronounced ability to form biofilms. No significant correlation was found between surface hydrophobicity and biofilm formation capability. In addition, we found that after biofilm formation, the adhesion and invasion of cells were enhanced and drug resistance increased. Therefore, we hypothesized that the formation of biofilm makes L. monocytogenes more virulent and more difficult to remove by antibiotics. Lastly, utilizing RT-PCR, we detected the expression levels of genes associated with biofilm formation, including those involved in quorum sensing (QS), flagellar synthesis, and extracellular polymer production. These genes were significantly upregulated after biofilm formation. These findings underscore the critical relationship between extracellular polymers, self-agglutination abilities, and biofilm formation. In conclusion, the establishment of biofilms not only enhances L. monocytogenes' capacity for cell invasion and adhesion but also significantly increases its resistance to drugs, presenting a substantial threat to food safety.}, }
@article {pmid38611358, year = {2024}, author = {Kulišová, M and Rabochová, M and Lorinčík, J and Brányik, T and Hrudka, J and Scholtz, V and Jarošová Kolouchová, I}, title = {Exploring Non-Thermal Plasma and UV Radiation as Biofilm Control Strategies against Foodborne Filamentous Fungal Contaminants.}, journal = {Foods (Basel, Switzerland)}, volume = {13}, number = {7}, pages = {}, pmid = {38611358}, issn = {2304-8158}, support = {22-13745S//Czech Science Foundation/ ; LM2023041//Ministry of Education Youth and Sports/ ; }, abstract = {In recent years, non-thermal plasma (NTP) has emerged as a promising tool for decontamination and disinfection within the food industry. Given the increasing resistance of microbial biofilms to conventional disinfectants and their adverse environmental effects, this method has significant potential for eliminating biofilm formation or mitigating the metabolic activity of grown biofilms. A comparative study was conducted evaluating the efficacy of UV radiation and NTP in eradicating mature biofilms of four common foodborne filamentous fungal contaminants: Alternaria alternata, Aspergillus niger, Fusarium culmorum, and Fusarium graminearum. The findings reveal that while UV radiation exhibits variable efficacy depending on the duration of exposure and fungal species, NTP induces substantial morphological alterations in biofilms, disrupting hyphae, and reducing extracellular polymeric substance production, particularly in A. alternata and F. culmorum. Notably, scanning electron microscopy analysis demonstrates significant disruption of the hyphae in NTP-treated biofilms, indicating its ability to penetrate the biofilm matrix, which is a promising outcome for biofilm eradication strategies. The use of NTP could offer a more environmentally friendly and potentially more effective alternative to traditional disinfection methods.}, }
@article {pmid38610253, year = {2024}, author = {Longo, M and Lelchat, F and Le Baut, V and Rioual, S and Faÿ, F and Lescop, B and Hellio, C}, title = {Tracking of Bacteriophage Predation on Pseudomonas aeruginosa Using a New Radiofrequency Biofilm Sensor.}, journal = {Sensors (Basel, Switzerland)}, volume = {24}, number = {7}, pages = {}, pmid = {38610253}, issn = {1424-8220}, mesh = {Animals ; *Bacteriophages ; Pseudomonas aeruginosa ; Predatory Behavior ; *Pseudomonas Infections ; Biofilms ; }, abstract = {Confronting the challenge of biofilm resistance and widespread antimicrobial resistance (AMR), this study emphasizes the need for innovative monitoring methods and explores the potential of bacteriophages against bacterial biofilms. Traditional methods, like optical density (OD) measurements and confocal microscopy, crucial in studying biofilm-virus interactions, often lack real-time monitoring and early detection capabilities, especially for biofilm formation and low bacterial concentrations. Addressing these gaps, we developed a new real-time, label-free radiofrequency sensor for monitoring bacteria and biofilm growth. The sensor, an open-ended coaxial probe, offers enhanced monitoring of bacterial development stages. Tested on a biological model of bacteria and bacteriophages, our results indicate the limitations of traditional OD measurements, influenced by factors like sedimented cell fragments and biofilm formation on well walls. While confocal microscopy provides detailed 3D biofilm architecture, its real-time monitoring application is limited. Our novel approach using radio frequency measurements (300 MHz) overcomes these shortcomings. It facilitates a finer analysis of the dynamic interaction between bacterial populations and phages, detecting real-time subtle changes. This method reveals distinct phases and breakpoints in biofilm formation and virion interaction not captured by conventional techniques. This study underscores the sensor's potential in detecting irregular viral activity and assessing the efficacy of anti-biofilm treatments, contributing significantly to the understanding of biofilm dynamics. This research is vital in developing effective monitoring tools, guiding therapeutic strategies, and combating AMR.}, }
@article {pmid38609420, year = {2024}, author = {Dzofou Ngoumelah, D and Heggeset, TMB and Haugen, T and Sulheim, S and Wentzel, A and Harnisch, F and Kretzschmar, J}, title = {Author Correction: Effect of model methanogens on the electrochemical activity, stability, and microbial community structure of Geobacter spp. dominated biofilm anodes.}, journal = {NPJ biofilms and microbiomes}, volume = {10}, number = {1}, pages = {41}, doi = {10.1038/s41522-024-00513-9}, pmid = {38609420}, issn = {2055-5008}, }
@article {pmid38609218, year = {2024}, author = {Gao, B and Cai, H and Xu, B and Yang, F and Dou, X and Dong, Q and Yan, H and Bu, X and Li, Z}, title = {Growth, biofilm formation, and motility of Listeria monocytogenes strains isolated from food and clinical samples located in Shanghai (China).}, journal = {Food research international (Ottawa, Ont.)}, volume = {184}, number = {}, pages = {114232}, doi = {10.1016/j.foodres.2024.114232}, pmid = {38609218}, issn = {1873-7145}, mesh = {Animals ; China ; *Listeria monocytogenes/genetics ; Food ; Biofilms ; *Catfishes ; }, abstract = {Listeria monocytogenes is a common foodborne pathogen that frequently causes global outbreaks. In this study, the growth characteristics, biofilm formation ability, motility ability and whole genome of 26 L. monocytogenes strains isolated from food and clinical samples in Shanghai (China) from 2020 to 2022 were analyzed. There are significant differences among isolates in terms of growth, biofilm formation, motility, and gene expression. Compared with other sequence type (ST) types, ST1930 type exhibited a significantly higher maximum growth rate, the ST8 type demonstrated a stronger biofilm formation ability, and the ST121 type displayed greater motility ability. Furthermore, ST121 exhibited significantly high mRNA expression levels compared with other ST types in virulence genes mpl, fbpA and fbpB, the quorum sensing gene luxS, starvation response regulation gene relA, and biofilm adhesion related gene bapL. Whole-genome sequencing (WGS) analyses indicated the isolates of lineage I were mostly derived from clinical, and the isolates of lineage II were mostly derived from food. The motility ability, along with the expression of genes associated with motility (motA and motB), exhibited a significantly higher level in lineage II compared with lineage I. The isolates from food exhibited significantly higher motility ability compared with isolates from clinical. By integrating growth, biofilm formation, motility phenotype with molecular and genotyping information, it is possible to enhance comprehension of the association between genes associated with these characteristics in L. monocytogenes.}, }
@article {pmid38608889, year = {2024}, author = {Chu, WC and Gao, YY and Wu, YX and Liu, FF}, title = {Biofilm of petroleum-based and bio-based microplastics in seawater in response to Zn(II): Biofilm formation, community structure, and microbial function.}, journal = {The Science of the total environment}, volume = {928}, number = {}, pages = {172397}, doi = {10.1016/j.scitotenv.2024.172397}, pmid = {38608889}, issn = {1879-1026}, mesh = {*Biofilms/drug effects ; *Seawater/chemistry/microbiology ; *Microplastics/toxicity ; *Zinc ; *Water Pollutants, Chemical/analysis ; Petroleum ; Bacteria/drug effects ; Polyesters ; Bacterial Physiological Phenomena/drug effects ; }, abstract = {Microplastic biofilms are novel vectors for the transport and spread of pathogenic and drug-resistant bacteria. With the increasing use of bio-based plastics, there is an urgent need to investigate the microbial colonization characteristics of these materials in seawater, particularly in comparison with conventional petroleum-based plastics. Furthermore, the effect of co-occurring contaminants, such as heavy metals, on the formation of microplastic biofilms and bacterial communities remains unclear. In this study, we compared the biofilm bacterial community structure of petroleum-based polyethylene (PE) and bio-based polylactic acid (PLA) in seawater under the influence of zinc ions (Zn[2+]). Our findings indicate that the biofilm on PLA microplastics in the late stage was impeded by the formation of a mildly acidic microenvironment resulting from the hydrolysis of the ester group on PLA. The PE surface had higher bacterial abundance and diversity, with a more intricate symbiotic pattern. The bacterial structures on the two types of microplastics were different; PE was more conducive to the colonization of anaerobic bacteria, whereas PLA was more favorable for the colonization of aerobic and acid-tolerant species. Furthermore, Zn increased the proportion of the dominant genera that could utilize microplastics as a carbon source, such as Alcanivorax and Nitratireductor. PLA had a greater propensity to harbor and disseminate pathogenic and drug-resistant bacteria, and Zn promoted the enrichment and spread of harmful bacteria such as, Pseudomonas and Clostridioides. Therefore, further research is essential to fully understand the potential environmental effects of bio-based microplastics and the role of heavy metals in the dynamics of bacterial colonization.}, }
@article {pmid38608880, year = {2024}, author = {Zhao, Y and Zhang, J and Ni, M and Pan, Y and Li, L and Ding, Y}, title = {Cultivation of phosphate-accumulating biofilm: Study of the effects of acyl-homoserine lactones (AHLs) and cyclic dimeric guanosine monophosphate (c-di-GMP) on the formation of biofilm and the enhancement of phosphate metabolism capacity.}, journal = {The Science of the total environment}, volume = {928}, number = {}, pages = {172408}, doi = {10.1016/j.scitotenv.2024.172408}, pmid = {38608880}, issn = {1879-1026}, mesh = {*Biofilms ; *Acyl-Butyrolactones/metabolism ; *Phosphates/metabolism ; *Cyclic GMP/metabolism/*analogs &amp; derivatives ; *Waste Disposal, Fluid/methods ; Bioreactors/microbiology ; Sewage/microbiology ; }, abstract = {This study investigated the mechanisms of microbial growth and metabolism during biofilm cultivation in the biofilm sequencing batch reactor (BSBR) process for phosphate (P) enrichment. The results showed that the sludge discharge was key to biofilm growth, as it terminated the competition for carbon (C) source between the nascent biofilm and the activated sludge. For the tested reactor, after the sludge discharge on 18 d, P metabolism and C source utilization improved significantly, and the biofilm grew rapidly. The P concentration of the recovery liquid reached up to 157.08 mg/L, which was sufficient for further P recovery via mineralization. Meta-omics methods were used to analyze metabolic pathways and functional genes in microbial growth during biofilm cultivation. It appeared that the sludge discharge activated the key genes of P metabolism and inhibited the key genes of C metabolism, which strengthened the polyphosphate-accumulating metabolism (PAM) as a result. The sludge discharge not only changed the types of polyphosphate-accumulating organisms (PAOs) but also promoted the growth of dominant PAOs. Before the sludge discharge, the necessary metabolic abilities that were spread among different microorganisms gradually concentrated into a small number of PAOs, and after the sludge discharge, they further concentrated into Candidatus_Contendobacter (P3) and Candidatus_Accumulibacter (P17). The messenger molecule C-di-GMP, produced mostly by P3 and P17, facilitated P enrichment by regulating cellular P and C metabolism. The glycogen-accumulating organism (GAO) Candidatus_Competibacter secreted N-Acyl homoserine lactones (AHLs), which stimulated the secretion of protein in extracellular polymeric substances (EPS), thus promoting the adhesion of microorganisms to biofilm and improving P metabolism via EPS-based P adsorption. Under the combined action of the dominant GAOs and PAOs, AHLs and C-di-GMP mediated QS to promote biofilm development and P enrichment. The research provides theoretical support for the cultivation of biofilm and its wider application.}, }
@article {pmid38605850, year = {2024}, author = {Cheng, Y and Huangfu, Y and Zhao, T and Wang, L and Yang, J and Liu, J and Feng, Z and Que, K}, title = {Thermosensitive hydrogel with programmed dual-octenidine release combating biofilm for the treatment of apical periodontitis.}, journal = {Regenerative biomaterials}, volume = {11}, number = {}, pages = {rbae031}, pmid = {38605850}, issn = {2056-3418}, abstract = {The utilization of intracanal medicaments is an indispensable procedure in root-canal treatment. However, the conventional intracanal medicaments still need improvement regarding antimicrobial efficacy and ease of clinical operation. To address the above issues, OCT/PECT@OCT + ALK composite hydrogel characterized by programming sequential release of dual antimicrobial agents has been proposed. Thanks to the self-assemble ability of amphiphilic copolymer poly(ε-caprolactone-co-1,4,8-trioxa [4.6]spiro-9-undecanone)-poly(ethylene glycol)-poly(ε-caprolactone-co-1,4,8-trioxa[4.6]spiro-9-undecanone) (PECT), dual hydrophilic and hydrophobic antimicrobial agents could be easily encapsulated in the hydrogel system and tailored for sequential drug release for a better antibiofilm effect. The hydrophilic octenidine (Octenidine dihydrochloride, OCT-HCl) is encapsulated in the hydrophilic part of hydrogel for instantaneous elevating the drug concentration through bursting release, and the hydrophobic octenidine (Octenidine, OCT) is further loaded into the PECT nanoparticles to achieve a slower and sustained-release profile. Additionally, calcium hydroxide (Ca(OH)2) was incorporated into the system and evenly dispersed among PECT nanoparticles to create an alkaline (ALK) environment, synergistically enhancing the antibiofilm effect with higher efficiency and prolonged duration. The antibiofilm effect has been demonstrated in root-canal models and apical periodontitis rats, exhibiting superior performance compared to clinically used Ca(OH)2 paste. This study demonstrates that OCT/PECT@OCT + ALK composite thermosensitive hydrogel is a potential intracanal medicament with excellent antibiofilm effect and clinical operability.}, }
@article {pmid38605736, year = {2024}, author = {Sagar, PK and Sharma, P and Singh, R}, title = {Anti-Quorum Sensing and Anti-Biofilm Activity of Ginger (Zingiber officinale) Rhizomes against Multidrug-Resistant Clinical Isolates of Pseudomonas aeruginosa.}, journal = {Avicenna journal of medical biotechnology}, volume = {16}, number = {1}, pages = {49-56}, pmid = {38605736}, issn = {2008-2835}, abstract = {BACKGROUND: The aim of this study was to determination of Anti-Quorum Sensing (AQS) and anti-biofilm potential of the methanol extract of ginger (Zingiber officinale) rhizomes against multidrug-resistant clinical isolates of Pseudomonas aeruginosa (P. aeruginosa).<br><br>METHODS: The AQS activity of ginger was determined against Chromobacterium violaceum (C. violaceum) ATCC 12472 (CV12472), a biosensor strain, in qualitative manner using the agar well diffusion method. The violacein pigment inhibition was assessed to confirm AQS activity of ginger. The AQS potential of sub-minimum Inhibitory Concentrations (sub-MICs) of the ginger extract was determined by targeting different QS regulated virulence factors, including swarming motility (using swarm diameter measurement method), pyocyanin pigment (using chloroform extraction method), Exopolysaccharide (EPS) (using phenol-sulphuric acid method), and biofilm formation (using microtiter plate assay), against clinical isolates (CIs 2, 3, and 4) and standard reference strain of P. aeruginosa (PA01).<br><br>RESULTS: The AQS activity of methanol extract of ginger was confirmed against C. violaceum (CV12472) as inhibition of violacein pigment formation without effecting the growth of CIs and PA01 of P. aeruginosa. The ginger extract exhibited concentration-dependent inhibition of virulence factors and biofilm formation. The maximum reduction was found in swarming motility, pyocyanin, EPS and biofilm formation against PA01 (51.38%), CI3 (57.91%), PA01 (63.29%) and CI2 (64.37%), respectively at 1/2 MIC of ginger extract.<br><br>CONCLUSION: The results of present study revealed the effective AQS and anti-biofilm potential of Zingiber officinale rhizome methanol extract at a reduced dose (sub-MICs). The extract may be explored as an agent of antimicrobial compounds having AQS and anti-biofilm activity for controlling microbial infection and also for reducing the chances of emergence of resistance in P. aeruginosa.}, }
@article {pmid38604376, year = {2024}, author = {Lin, YT and Wang, YC and Xue, YM and Tong, Z and Jiang, GY and Hu, XR and Crittenden, JC and Wang, C}, title = {Decoding the influence of low temperature on biofilm development: The hidden roles of c-di-GMP.}, journal = {The Science of the total environment}, volume = {927}, number = {}, pages = {172376}, doi = {10.1016/j.scitotenv.2024.172376}, pmid = {38604376}, issn = {1879-1026}, mesh = {*Bacteria ; Bacterial Physiological Phenomena ; *Biofilms ; Cold Temperature ; *Cyclic GMP/analogs &amp; derivatives/metabolism ; Extracellular Polymeric Substance Matrix ; Wastewater/microbiology ; }, abstract = {Biofilms are widely used and play important roles in biological processes. Low temperature of wastewater inhibits the development of biofilms derived from wastewater activated sludge. However, the specific mechanism of temperature on biofilm development is still unclear. This study explored the mechanism of temperature on biofilm development and found a feasible method to enhance biofilm development at low temperature. The amount of biofilm development decreased by approximately 66 % and 55 % at 4 °C and 15 °C, respectively, as compared to 28 °C. The cyclic dimeric guanosine monophosphate (c-di-GMP) concentration also decreased at low temperature and was positively correlated with extracellular polymeric substance (EPS) content, formation, and adhesion strength. Microbial community results showed that low temperature inhibited the normal survival of most microorganisms, but promoted the growth of some psychrophile bacteria like Sporosarcina, Caldilineaceae, Gemmataceae, Anaerolineaceae and Acidobacteriota. Further analysis of functional genes demonstrated that the abundance of functional genes related to the synthesis of c-di-GMP (K18968, K18967 and K13590) decreased at low temperature. Subsequently, the addition of exogenous spermidine increased the level of intracellular c-di-GMP and alleviated the inhibition effect of low temperature on biofilm development. Therefore, the possible mechanism of low temperature on biofilm development could be the inhibition of the microorganism activity and reduction of the communication level between cells, which is the closely related to the EPS content, formation, and adhesion strength. The enhancement of c-di-GMP level through the exogenous addition of spermidine provides an alternative strategy to enhance biofilm development at low temperatures. The results of this study enhance the understanding of the influence of temperature on biofilm development and provide possible strategies for enhancing biofilm development at low temperatures.}, }
@article {pmid38602224, year = {2024}, author = {Senhaji-Kacha, A and Akir, A and Broncano-Lavado, A and Esteban, J}, title = {Biofilm prevention concentration of clarithromycin against clinically relevant species of nontuberculous mycobacteria.}, journal = {Revista espanola de quimioterapia : publicacion oficial de la Sociedad Espanola de Quimioterapia}, volume = {37}, number = {3}, pages = {266-269}, pmid = {38602224}, issn = {1988-9518}, mesh = {*Clarithromycin/pharmacology ; *Biofilms/drug effects ; *Anti-Bacterial Agents/pharmacology ; *Nontuberculous Mycobacteria/drug effects ; Humans ; *Microbial Sensitivity Tests ; Mycobacterium Infections, Nontuberculous/microbiology/drug therapy/prevention &amp; control ; Mycobacterium avium Complex/drug effects ; Mycobacterium abscessus/drug effects ; }, abstract = {OBJECTIVE: Mycobacterium avium complex (MAC) and Mycobacterium abscessus are a group of nontuberculous mycobacteria (NTM) that have been described as human pathogens. Their ability to develop biofilms in tissues and medical devices is one of the most important pathogenicity factors, with important implications in diagnosis and treatment. Macrolides are usually considered one of the bases of this treatment.<br><br>METHODS: Here we have studied the biofilm prevention concentration (BPC) of 16 strains (n=16) with clarithromycin to avoid the biofilm development by these NTM.<br><br>RESULTS: In this study, all M. abscessus strains have similar BPC, while MAC strains showed different values. For MAC the concentrations ranged between 1-16 mg/L, while for M. abscessus the concentration was 32 mg/L for all strains except one that was 64 mg/L.<br><br>CONCLUSIONS: These results open the possibility of using macrolides for the prevention of biofilm development in patients with a risk of developing NTM disease.}, }
@article {pmid38601931, year = {2024}, author = {Naudin, SA and Ferran, AA and Imazaki, PH and Arpaillange, N and Marcuzzo, C and Vienne, M and Demmou, S and Bousquet-Mélou, A and Ramon-Portugal, F and Lacroix, MZ and Hoede, C and Barret, M and Dupouy, V and Bibbal, D}, title = {Development of an in vitro biofilm model for the study of the impact of fluoroquinolones on sewer biofilm microbiota.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1377047}, pmid = {38601931}, issn = {1664-302X}, abstract = {Sewer biofilms are likely to constitute hotspots for selecting and accumulating antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs). This study aimed to optimize culture conditions to obtain in vitro biofilms, mimicking the biofilm collected in sewers, to study the impact of fluoroquinolones (FQs) on sewer biofilm microbiota. Biofilms were grown on coupons in CDC Biofilm Reactors®, continuously fed with nutrients and inoculum (1/100 diluted wastewater). Different culture conditions were tested: (i) initial inoculum: diluted wastewater with or without sewer biofilm, (ii) coupon material: concrete vs. polycarbonate, and (iii) time of culture: 7 versus 14 days. This study found that the biomass was highest when in vitro biofilms were formed on concrete coupons. The biofilm taxonomic diversity was not affected by adding sewer biofilm to the initial inoculum nor by the coupon material. Pseudomonadales, Burkholderiales and Enterobacterales dominated in the sewer biofilm composition, whereas in vitro biofilms were mainly composed of Enterobacterales. The relative abundance of qnrA, B, D and S genes was higher in in vitro biofilms than sewer biofilm. The resistome of sewer biofilm showed the highest Shannon diversity index compared to wastewater and in vitro biofilms. A PCoA analysis showed differentiation of samples according to the nature of the sample, and a Procrustes analysis showed that the ARG changes observed were linked to changes in the microbial community. The following growing conditions were selected for in vitro biofilms: concrete coupons, initial inoculation with sewer biofilm, and a culture duration of 14 days. Then, biofilms were established under high and low concentrations of FQs to validate our in vitro biofilm model. Fluoroquinolone exposure had no significant impact on the abundance of qnr genes, but high concentration exposure increased the proportion of mutations in gyrA (codons S83L and D87N) and parC (codon S80I). In conclusion, this study allowed the determination of the culture conditions to develop an in vitro model of sewer biofilm; and was successfully used to investigate the impact of FQs on sewer microbiota. In the future, this setup could be used to clarify the role of sewer biofilms in disseminating resistance to FQs in the environment.}, }
@article {pmid38601817, year = {2024}, author = {Klein, E and Wurst, R and Rehnlund, D and Gescher, J}, title = {Elucidating the development of cooperative anode-biofilm-structures.}, journal = {Biofilm}, volume = {7}, number = {}, pages = {100193}, pmid = {38601817}, issn = {2590-2075}, abstract = {Microbial electrochemical systems are a highly versatile platform technology with a particular focus on the interplay of chemical and electrical energy conversion and offer immense potential for a sustainable bioeconomy. The industrial realization of this potential requires a critical focus on biofilm optimization if performance is to be controlled over a long period of time. Moreover, the aspect and influence of cooperativity has to be addressed as many applied anodic bioelectrochemical systems will most likely be operated with a diversity of interacting microbial species. Hence, the aim of this study was to analyze how interspecies dependence and cooperativity of a model community influence the development of anodic biofilms. To investigate biofilm activity in a spatially resolved manner, a microfluidic bioelectrochemical flow cell was developed that can be equipped with user-defined electrode materials and operates under laminar flow conditions. With this infrastructure, the development of single and co-culture biofilms of the two model organisms Shewanella oneidensis and Geobacter sulfurreducens on graphite electrodes was monitored by optical coherence tomography analysis. The interdependence in the co-culture biofilm was achieved by feeding the community with lactate, which is converted by S. oneidensis into acetate, which in turn serves as substrate for G. sulfurreducens. The results show that co-cultivation resulted in the formation of denser biofilms than in single culture. Moreover, we hypothesize that S. oneidensis in return utilizes the conductive biofilm matrix build by G. sulfurreducens for direct interspecies electron transfer (DIET) to the anode. FISH analysis revealed that the biofilms consisted of approximately two-thirds G. sulfurreducens cells, which most likely formed a conductive 3D network throughout the biofilm matrix, in which evenly distributed tubular S. oneidensis colonies were embedded without direct contact to the anode surface. Live/dead staining shows that the outermost biofilm contained almost exclusively dead cells (98 %), layers near the anode contained 45-56 % and the entire biofilm contained 82 % live cells. Our results exemplify how the architecture of the exoelectrogenic biofilm dynamically adapts to the respective process conditions.}, }
@article {pmid38596384, year = {2024}, author = {Ren, J and Wang, M and Zhou, W and Liu, Z}, title = {Efflux pumps as potential targets for biofilm inhibition.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1315238}, pmid = {38596384}, issn = {1664-302X}, abstract = {Biofilms account for a great deal of infectious diseases and contribute significantly to antimicrobial resistance. Efflux pumps confer antimicrobial resistance to microorganisms and involve multiple processes of biofilm formation. Efflux pump inhibitors (EPIs) are attracting considerable attention as a biofilm inhibition strategy. The regulatory functions of efflux pumps in biofilm formation such as mediating adherence, quorum sensing (QS) systems, and the expression of biofilm-associated genes have been increasingly identified. The versatile properties confer efflux pumps both positive and negative effects on biofilm formation. Furthermore, the expression and function of efflux pumps in biofilm formation are species-specific. Therefore, this review aims to detail the double-edged sword role of efflux pumps in biofilm formation to provide potential inhibition targets and give an overview of the effects of EPIs on biofilm formation.}, }
@article {pmid38596377, year = {2024}, author = {Chamlagain, M and Hu, J and Sionov, RV and Steinberg, D}, title = {Anti-bacterial and anti-biofilm activities of arachidonic acid against the cariogenic bacterium Streptococcus mutans.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1333274}, pmid = {38596377}, issn = {1664-302X}, abstract = {Streptococcus mutans is a Gram-positive, facultative anaerobic bacterium, which causes dental caries after forming biofilms on the tooth surface while producing organic acids that demineralize enamel and dentin. We observed that the polyunsaturated arachidonic acid (AA) (ω-6; 20:4) had an anti-bacterial activity against S. mutans, which prompted us to investigate its mechanism of action. The minimum inhibitory concentration (MIC) of AA on S. mutans was 25 μg/ml in the presence of 5% CO2, while it was reduced to 6.25-12.5 μg/ml in the absence of CO2 supplementation. The anti-bacterial action was due to a combination of bactericidal and bacteriostatic effects. The minimum biofilm inhibitory concentration (MBIC) was the same as the MIC, suggesting that part of the anti-biofilm effect was due to the anti-bacterial activity. Gene expression studies showed decreased expression of biofilm-related genes, suggesting that AA also has a specific anti-biofilm effect. Flow cytometric analyses using potentiometric DiOC2(3) dye, fluorescent efflux pump substrates, and live/dead SYTO 9/propidium iodide staining showed that AA leads to immediate membrane hyperpolarization, altered membrane transport and efflux pump activities, and increased membrane permeability with subsequent membrane perforation. High-resolution scanning electron microscopy (HR-SEM) showed remnants of burst bacteria. Furthermore, flow cytometric analysis using the redox probe 2',7'-dichlorofluorescein diacetate (DCFHDA) showed that AA acts as an antioxidant in a dose-dependent manner. α-Tocopherol, an antioxidant that terminates the radical chain, counteracted the anti-bacterial activity of AA, suggesting that oxidation of AA in bacteria leads to the production of cytotoxic radicals that contribute to bacterial growth arrest and death. Importantly, AA was not toxic to normal Vero epithelial cells even at 100 μg/ml, and it did not cause hemolysis of erythrocytes. In conclusion, our study shows that AA is a potentially safe drug that can be used to reduce the bacterial burden of cariogenic S. mutans.}, }
@article {pmid38596374, year = {2024}, author = {Zhao, Y and Guo, S and Li, S and Ye, E and Wang, W and Wang, T and Wen, Y and Guo, L}, title = {Ultrasonic-assisted extraction, anti-biofilm activity, and mechanism of action of Ku Shen (Sophorae Flavescentis Radix) extracts against Vibrio parahaemolyticus.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1379341}, pmid = {38596374}, issn = {1664-302X}, abstract = {The objective of this study is to optimize the ultrasonic-assisted extraction process of Ku Shen (Sophorae Flavescentis Radix) extracts (KSE) against Vibrio parahaemolyticus and explore their anti-biofilm activity and mechanism of action. The ultrasonic-assisted extraction process of KSE optimized by single factor experiment, Box-Behnken design and response surface methodology was as follows: 93% ethanol as solvent, liquid/material ratio of 30 mL/g, ultrasonic power of 500 W, extraction temperature of 80°C and time of 30 min. Under these conditions, the diameter of inhibition circle of KSE was 15.60 ± 0.17 mm, which had no significant difference with the predicted value. The yield of dried KSE is 32.32 ± 0.57% and the content of total flavonoids in KSE was 57.02 ± 5.54%. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of KSE against V. parahaemolyticus were 0.25 and 0.5 mg/mL, respectively. Crystal violet staining, Congo red plate, spectrophotometry, CCK-8 and scanning electron microscopy were used to investigate the activity and mechanism of action of KSE against V. parahaemolyticus biofilm. The results showed that the sub-MIC of KSE could significantly inhibit biofilm formation, reduce the synthesis of polysaccharide intercellular adhesin (PIA) and the secretion of extracellular DNA. In addition, the inhibition rate of biofilm formation and clearance rate of mature biofilm of 1.0 mg/mL KSE were 85.32 and 74.04%, and the reduction rate of metabolic activity of developing and mature biofilm were 77.98 and 74.46%, respectively. These results were confirmed by visual images obtained by scanning electron microscopy. Therefore, KSE has the potential to further isolate the anti-biofilm agent and evaluate it for the preservation process of aquatic products.}, }
@article {pmid38596007, year = {2024}, author = {Gricajeva, A and Buchovec, I and Kalėdienė, L and Badokas, K and Vitta, P}, title = {Evaluation of visible light and natural photosensitizers against Staphylococcus epidermidis and Staphylococcus saprophyticus planktonic cells and biofilm.}, journal = {Heliyon}, volume = {10}, number = {7}, pages = {e28811}, pmid = {38596007}, issn = {2405-8440}, abstract = {Antimicrobial photoinactivation (API) has shown some promise in potentially treating different nosocomial bacterial infections, however, its application on staphylococci, especially other than Staphylococcus aureus or methicillin-resistant S. aureus (MRSA) species is still limited. Although S. aureus is a well-known and important nosocomial pathogen, several other species of the genus, particularly coagulase-negative Staphylococcus (CNS) species such as Staphylococcus epidermidis and Staphylococcus saprophyticus, can also cause healthcare-associated infections and foodborne intoxications. CNS are often involved in resilient biofilm formation on medical devices and can cause infections in patients with compromised immune systems or those undergoing invasive procedures. In this study, the effects of chlorophyllin and riboflavin-mediated API on S. epidermidis and S. saprophyticus planktonic cells and biofilm are demonstrated for the first time. Based on the residual growth determination and metabolic reduction ability changes, higher inactivating efficiency of chlorophyllin-mediated API was determined against the planktonic cells of both tested species of bacteria and against S. saprophyticus biofilm. Some insights on whether aqueous solutions of riboflavin and chlorophyllin, when illuminated with optimal exciting wavelength (440 nm and 402 nm, respectively) generate O2[-•], are also provided in this work.}, }
@article {pmid38595719, year = {2024}, author = {ElNaggar, MH and Abdelmohsen, UR and Abdel Bar, FM and Kamer, AA and Bringmann, G and Elekhnawy, E}, title = {Investigation of bioactive components responsible for the antibacterial and anti-biofilm activities of Caroxylon volkensii by LC-QTOF-MS/MS analysis and molecular docking.}, journal = {RSC advances}, volume = {14}, number = {16}, pages = {11388-11399}, pmid = {38595719}, issn = {2046-2069}, abstract = {Caroxylon volkensii is a wild desert plant of the family Amaranthaceae. This study represents the first report of the metabolomic profiling of C. volkensii by liquid chromatography quadrupole-time-of-flight tandem mass spectrometry (LC-QTOF-MS/MS). The dereplication study of its secondary metabolites led to the characterization of 66 known compounds. These compounds include catecholamines, tyramine derivatives, phenolic acids, triterpenoids, flavonoids, and others. A new tyramine derivative, alongside other known compounds, was reported for the first time in the Amaranthaceae family. The new derivative and the first-reported compounds were putatively identified through MS/MS fragmentation data. Given the notorious taxonomical challenges within the genus Salsola, to which C. volkensii previously belonged, our study could offer a valuable insight into its chemical fingerprint and phylogenetic relationship to different Salsola species. The antibacterial potential of C. volkensii methanolic extract (CVM) against Pseudomonas aeruginosa was screened. The minimum inhibitory concentration (MIC) of CVM ranged from 32 to 256 μg mL[-1]. The anti-quorum sensing potential of CVM resulted in a decrease in the percentage of strong and moderate biofilm-forming isolates from 47.83% to 17.39%. It revealed a concentration-dependent inhibitory activity on violacein formation by Chromobacterium violaceum. Moreover, CVM exhibited an in vivo protective potential against the killing capacity of P. aeruginosa isolates. A molecular docking study revealed that the quorum-sensing inhibitory effect of CVM can be attributed to the binding of tyramine conjugates, ethyl-p-digallate, and isorhamnetin to the transcriptional global activator LasR.}, }
@article {pmid38595637, year = {2024}, author = {Alam, MK and Alruwaili, SRF and Alderaan, RAI and Alanazi, DSA}, title = {Nanoparticles in Preventing Biofilm Formation on Orthodontic Brackets: Clinical Study.}, journal = {Journal of pharmacy &amp; bioallied sciences}, volume = {16}, number = {Suppl 1}, pages = {S534-S536}, pmid = {38595637}, issn = {0976-4879}, abstract = {UNLABELLED: This study investigates the effectiveness of nanoparticles in preventing the formation of biofilms on orthodontic brackets. Biofilm formation is a common concern during orthodontic treatment, as it can lead to oral health issues.<br><br>MATERIALS AND METHODS: The study utilized a randomized controlled trial design. The participants were divided into two groups: the experimental group and the control group. The experimental group received orthodontic brackets coated with nanoparticles, while the control group received regular brackets. The patients' oral hygiene was monitored, and plaque index scores were recorded at specific intervals.<br><br>RESULTS: The results of this study demonstrated a significant difference in biofilm formation between the two groups. The experimental group, which had orthodontic brackets with nanoparticle coatings, exhibited a lower plaque index compared to the control group. The mean plaque index score difference was statistically significant (P < 0.05), indicating that the nanoparticles effectively reduced biofilm formation on orthodontic brackets.<br><br>CONCLUSION: In conclusion, the findings of this clinical study suggest that the utilization of nanoparticles as coatings for orthodontic brackets can be an effective approach to prevent biofilm formation.}, }
@article {pmid38593965, year = {2024}, author = {Bounaga, A and Alsanea, A and Danouche, M and Rittmann, BE and Zhou, C and Boulif, R and Zeroual, Y and Benhida, R and Lyamlouli, K}, title = {Elemental sulfur biorecovery from phosphogypsum using oxygen-membrane biofilm reactor: Bioreactor parameters optimization, metagenomic analysis and metabolic prediction of the biofilm activity.}, journal = {Bioresource technology}, volume = {400}, number = {}, pages = {130680}, doi = {10.1016/j.biortech.2024.130680}, pmid = {38593965}, issn = {1873-2976}, mesh = {*Biofilms ; *Bioreactors/microbiology ; *Sulfur/metabolism ; *Oxygen/metabolism ; *Phosphorus ; *Calcium Sulfate/chemistry ; Membranes, Artificial ; Metagenomics/methods ; Bacteria/metabolism/genetics ; Sulfides ; Oxidation-Reduction ; }, abstract = {This work investigated elemental sulfur (S[0]) biorecovery from Phosphogypsum (PG) using sulfur-oxidizing bacteria in an O2-based membrane biofilm reactor (MBfR). The system was first optimized using synthetic sulfide medium (SSM) as influent, then switched to biogenic sulfide medium (BSM) generated by biological reduction of PG alkaline leachate. The results using SSM had high sulfide-oxidation efficiency (98 %), sulfide to S[0] conversion (∼90 %), and S[0] production rate up to 2.7 g S[0]/(m[2].d), when the O2/S ratio was ∼0.5 g O2/g S. With the BSM influent, the system maintained high sulfide-to-S[0] conversion rate (97 %), and S[0]-production rate of 1.6 g S[0]/(m[2].d). Metagenomic analysis revealed that Thauera was the dominant genus in SSM and BSM biofilms. Furthermore, influent composition affected the bacterial community structure and abundances of functional microbial sulfur genes, modifying the sulfur-transformation pathways in the biofilms. Overall, this work shows promise for O2-MBfR usage in S[0] biorecovery from PG-leachate and other sulfidogenic effluents.}, }
@article {pmid38592866, year = {2024}, author = {Matotoka, MM and Masoko, P}, title = {Evaluation of the Antioxidant, Cytotoxicity, Antibacterial, Anti-Motility, and Anti-Biofilm Effects of Myrothamnus flabellifolius Welw. Leaves and Stem Defatted Subfractions.}, journal = {Plants (Basel, Switzerland)}, volume = {13}, number = {6}, pages = {}, pmid = {38592866}, issn = {2223-7747}, support = {N624//University of Limpopo/ ; }, abstract = {The formation of biofilms underscores the challenge of treating bacterial infections. The study aimed to assess the antioxidant, cytotoxicity, antibacterial, anti-motility, and anti-biofilm effects of defatted fractions from Myrothamnus flabellifolius (resurrection plant). Antioxidant activity was assessed using DPPH radical scavenging and hydrogen peroxide assays. Cytotoxicity was screened using a brine shrimp lethality assay. Antibacterial activity was determined using the micro-dilution and growth curve assays. Antibiofilm potential was screened using the crystal violet and tetrazolium reduction assay. Liquid-liquid extraction of crude extracts concentrated polyphenols in the ethyl acetate and n-butanol fractions. Subsequently, these fractions had notable antioxidant activity and demonstrated broad-spectrum antibacterial activity against selected Gram-negative and Gram-positive bacteria and Mycobacterium smegmatis (MIC values < 630 μg/mL). Growth curves showed that the bacteriostatic inhibition by the ethyl acetate fractions was through the extension of the lag phase and/or suppression of the growth rate. The sub-inhibitory concentrations of the ethyl acetate fractions inhibited the swarming motility of Pseudomonas aeruginosa and Klebsiella pneumoniae by 100% and eradicated more than 50% of P. aeruginosa biofilm biomass. The polyphenolic content of M. flabellifolius plays an important role in its antibacterial, anti-motility, and antibiofilm activity, thus offering an additional strategy to treat biofilm-associated infections.}, }
@article {pmid38590167, year = {2024}, author = {Li, J and Yu, J and Song, Y and Wang, S and Mu, G and Tuo, Y}, title = {Exopolysaccharides and Surface-Layer Proteins Expressed by Biofilm-State Lactiplantibacillus plantarum Y42 Play Crucial Role in Preventing Intestinal Barrier and Immunity Dysfunction of Balb/C Mice Infected by Listeria monocytogenes ATCC 19115.}, journal = {Journal of agricultural and food chemistry}, volume = {72}, number = {15}, pages = {8581-8594}, doi = {10.1021/acs.jafc.4c00460}, pmid = {38590167}, issn = {1520-5118}, mesh = {Mice ; Animals ; *Listeria monocytogenes ; Mice, Inbred BALB C ; Cytokines ; Biofilms ; *Intestinal Diseases ; }, abstract = {Our previous study showed that Lactiplantibacillus plantarum Y42 in the biofilm state can produce more exopolysaccharides and surface-layer proteins and showed a stronger promoting effect on intestinal barrier function than that in the planktonic state. In this study, oral administration of the live/pasteurized planktonic or biofilm L. plantarum Y42 and its metabolites (exopolysaccharides and surface-layer proteins) increased the expression of Occludin, Claudin-1, ZO-1, and MUC2 in the gut of the Balb/C mice after exposure to Listeria monocytogenes ATCC 19115 and inhibited the activation of the NLRP3 inflammasome pathway, which in turn reduced the levels of inflammatory cytokines IL-1β and IL-18 in the serum of the mice. Furthermore, oral administration of the live/pasteurized planktonic or biofilm L. plantarum Y42 and its metabolites increased the abundance of beneficial bacteria (e.g., Lachnospiraceae_NK4A136_group and Prevotellaceae_UCG-001) while reducing the abundance of harmful bacteria (e.g., norank_f__Muribaculaceae) in the gut of the mice, in line with the increase of short-chain fatty acids and indole derivatives in the feces of the mice. Notably, biofilm L. plantarum Y42 exerted a better preventing effect on the intestinal barrier dysfunction of the Balb/C mice due to the fact that biofilm L. plantarumY42 expressed more exopolysaccharides and surface-layer proteins than the planktonic state. These results provide data support for the use of exopolysaccharides and surface-layer proteins extracted from biofilm-state L. plantarum Y42 as functional food ingredients in preventing intestinal barrier dysfunction.}, }
@article {pmid38588781, year = {2024}, author = {Yang, S and Peng, Y and Hou, F and Pang, H and Jiang, L and Sun, S and Li, J and Zhang, L}, title = {Rapid establishment of municipal sewage partial denitrification-anammox for nitrogen removal through inoculation with side-stream anammox biofilm without domestication.}, journal = {Bioresource technology}, volume = {400}, number = {}, pages = {130679}, doi = {10.1016/j.biortech.2024.130679}, pmid = {38588781}, issn = {1873-2976}, mesh = {*Biofilms ; *Denitrification ; *Nitrogen/metabolism ; *Sewage/microbiology ; Bacteria/metabolism ; Bioreactors/microbiology ; Anaerobiosis ; Water Purification/methods ; Oxidation-Reduction ; Carbon/metabolism ; Nitrites/metabolism ; }, abstract = {Mainstream partial denitrification anammox was achieved through inoculation of side-stream mature partial nitritation anammox biofilm without domestication. The contribution of anammox to nitrogen removal was 29.4 %. Moreover, prolonging anoxic hydraulic retention time and introducing side-stream nitrite under different carbon/nitrogen ratios enriched anammox bacteria. The abundance of anammox bacteria increased by ∼ 10 times ((2.19 ± 0.17) × 10[12] copies gene / g dry sludge) with a total relative abundance of 18.51 %. During 258 days of operation, the contribution of anammox to nitrogen removal gradually increased to 68.8 %. The total nitrogen in the effluent decreased to 8.84 mg/L with a total nitrogen removal efficiency of 76.4 % under a carbon/nitrogen ratio of 3. This paper proposes a novel way to rapidly achieve mainstream partial denitrification anammox via inoculation with side-stream mature partial nitritation anammox biofilm. This method achieves advanced nitrogen removal from municipal wastewater, even under low carbon/nitrogen ratios.}, }
@article {pmid38588056, year = {2024}, author = {Iungin, O and Shydlovska, O and Moshynets, O and Vasylenko, V and Sidorenko, M and Mickevičius, S and Potters, G}, title = {Metal-based nanoparticles: an alternative treatment for biofilm infection in hard-to-heal wounds.}, journal = {Journal of wound care}, volume = {33}, number = {Sup4a}, pages = {xcix-cx}, doi = {10.12968/jowc.2024.33.Sup4a.xcix}, pmid = {38588056}, issn = {0969-0700}, mesh = {Humans ; Biofilms ; Staphylococcus aureus ; Anti-Bacterial Agents/therapeutic use/pharmacology ; *Staphylococcal Infections ; Pseudomonas aeruginosa ; *Nanoparticles/therapeutic use ; *Wound Infection/drug therapy/microbiology ; }, abstract = {Metal-based nanoparticles (MNPs) are promoted as effective compounds in the treatment of bacterial infections and as possible alternatives to antibiotics. These MNPs are known to affect a broad spectrum of microorganisms using a multitude of strategies, including the induction of reactive oxygen species and interaction with the inner structures of the bacterial cells. The aim of this review was to summarise the latest studies about the effect of metal-based nanoparticles on pathogenic bacterial biofilm formed in wounds, using the examples of Gram-positive bacterium Staphylococcus aureus and Gram-negative bacterium Pseudomonas aeruginosa, as well as provide an overview of possible clinical applications.}, }
@article {pmid38585970, year = {2024}, author = {de Palma, TH and Powers, C and McPartland, MJ and Welch, JM and Ramsey, M}, title = {Essential genes for Haemophilus parainfluenzae survival and biofilm growth.}, journal = {bioRxiv : the preprint server for biology}, volume = {}, number = {}, pages = {}, doi = {10.1101/2024.03.31.587483}, pmid = {38585970}, issn = {2692-8205}, abstract = {Haemophilus parainfluenzae (Hp) is a Gram-negative, pleomorphic rod, highly prevalent and abundant as a commensal in the human oral cavity, and an infrequent extraoral opportunistic pathogen. Hp occupies multiple niches in the oral cavity, including the tongue dorsum, keratinized gingiva, and the supragingival plaque biofilm. As a member of the HACEK group, Hp is also known to cause infective endocarditis. Additionally, case reports have identified Hp as the causative agent of meningitis, septic arthritis, chronic osteomyelitis, septicemia, and a variety of other infectious diseases. Little is known about how Hp interacts with its neighbors in the healthy biofilm nor about its mechanisms of pathogenesis as an extraoral opportunistic pathogen. To address these unknowns, we identified the essential genomes of two Hp strains and the conditionally essential genes for their growth in in vitro biofilms aerobically and anaerobically. Using transposon insertion sequencing (TnSeq) with a highly saturated mariner transposon library in two strains, the ATCC33392 type-strain (Hp 392) and a commensal oral isolate EL1 (Hp EL1), we show that the essential genome of Hp 392 and Hp EL1 is composed of 395 and 384 genes, respectively. The core essential genome, consisting of 341 essential genes conserved between both strains, was composed of genes associated with genetic information processing, carbohydrate, protein, and energy metabolism. We also identified conditionally essential genes for aerobic and anaerobic biofilm growth, which were associated with carbohydrate and energy metabolism in both strains of Hp . Additionally, RNAseq analysis determined that most genes upregulated during anaerobic growth are not essential for Hp 392 anaerobic biofilm survival. The completion of this library and analysis under these conditions gives us a foundational insight into the basic biology of H. parainfluenzae in differing oxygen conditions, similar to its in vivo oral habitat. Further, the creation of this library presents a valuable tool for further investigation into conditionally essential genes for an organism that lives in close contact with many microbial species in the human oral habitat.}, }
@article {pmid38585655, year = {2024}, author = {Li, X and Tian, F and Zhang, B and Zhang, L and Chen, X and Lin, X and Wang, Y and Lin, X and Liu, Y}, title = {Quantitative proteomics analysis reveals an important role of the transcriptional regulator UidR in the bacterial biofilm formation of Aeromonas hydrophila.}, journal = {Frontiers in cellular and infection microbiology}, volume = {14}, number = {}, pages = {1380747}, pmid = {38585655}, issn = {2235-2988}, mesh = {*Bacterial Proteins/metabolism ; *Aeromonas hydrophila/metabolism ; Proteomics/methods ; Biofilms ; *Glyoxylates ; }, abstract = {INTRODUCTION: Bacterial biofilm is a well-known characteristic that plays important roles in diverse physiological functions, whereas the current intrinsic regulatory mechanism of its formation is still largely unknown.<br><br>METHODS: In the present study, a label-free based quantitative proteomics technology was conducted to compare the differentially expressed proteins (DEPs) between &#x394;uidR and the wild-type strain in the biofilm state.<br><br>RESULTS: The results showed that the deletion of gene uidR encoding a TetR transcriptional regulator significantly increased the biofilm formation in Aeromonas hydrophila. And there was a total of 220 DEPs, including 120 up-regulated proteins and 100 down-regulated proteins between &#x394;uidR and the wild-type strain based on the quantitative proteomics. Bioinformatics analysis suggested that uidR may affect bacterial biofilm formation by regulating some related proteins in glyoxylic acid and dicarboxylic acid pathway. The expressions of selected proteins involved in this pathway were further confirmed by q-PCR assay, and the results was in accordance with the quantitative proteomics data. Moreover, the deletion of four genes (AHA_3063, AHA_3062, AHA_4140 and aceB) related to the glyoxylic acid and dicarboxylic acid pathway lead to a significant decrease in the biofilm formation.<br><br>DISCUSSION: Thus, the results indicated that uidR involved in the regulatory of bacterial biofilm formation, and it may provide a potential target for the drug development and a new clue for the prevention of pathogenic A. hydrophila in the future.}, }
@article {pmid38584359, year = {2024}, author = {Akkoyunlu, A and Dülger, G}, title = {Exploring the antibiofilm effects on Escherichia coli biofilm associated with colon cancer and anticancer activities on HCT116 cell line of bee products.}, journal = {Biofouling}, volume = {40}, number = {3-4}, pages = {235-244}, doi = {10.1080/08927014.2024.2338106}, pmid = {38584359}, issn = {1029-2454}, mesh = {*Biofilms/drug effects ; Humans ; Animals ; *Bee Venoms/pharmacology ; *Escherichia coli/drug effects/physiology ; *Colonic Neoplasms/drug therapy ; Bees/drug effects ; HCT116 Cells ; *Propolis/pharmacology/chemistry ; *Fatty Acids/pharmacology ; *Antineoplastic Agents/pharmacology ; Honey ; Cell Proliferation/drug effects ; Pollen/chemistry ; Anti-Bacterial Agents/pharmacology ; Apoptosis/drug effects ; }, abstract = {The association between dysbiotic microbiota biofilm and colon cancer has recently begun to attract attention. In the study, the apitherapeutic effects of bee products (honey, bee venom, royal jelly, pollen, perga and propolis) obtained from the endemic Yığılca ecotype of Apis mellifera anatoliaca were investigated. Antibiofilm activity were performed by microplate assay using crystal violet staining to measure adherent biofilm biomass of Escherichia coli capable of forming biofilms. Bee venom showed the highest inhibition effect (73.98%) at 50% concentration. Honey, perga and royal jelly reduced biofilm formation by >50% at all concentrations. The antiproliferation effect on the HCT116 colon cancer cell line was investigated with the water‑soluble tetrazolium salt‑1 assay. After 48 h of honey application at 50% concentration, cell proliferation decreased by 86.51%. The high cytotoxic effects of royal jelly and bee venom are also remarkable. Additionally, apoptotic pathway analysis was performed by ELISA using caspase 3, 8 and 9 enzyme-linked immunosorbent assay kits. All bee products induced a higher expression of caspase 9 compared with caspase 8. Natural products that upregulate caspase proteins are promising therapeutic targets for proliferative diseases.}, }
@article {pmid38582469, year = {2024}, author = {Rahmatpour, A and Alizadeh, AH}, title = {Biofilm hydrogel derived from physical crosslinking (self-assembly) of xanthan gum and chitosan for removing Cd[2+], Ni[2+], and Cu[2+] from aqueous solution.}, journal = {International journal of biological macromolecules}, volume = {266}, number = {Pt 2}, pages = {131394}, doi = {10.1016/j.ijbiomac.2024.131394}, pmid = {38582469}, issn = {1879-0003}, mesh = {Adsorption ; *Biofilms ; Cadmium/chemistry ; *Chitosan/chemistry ; Copper/chemistry ; *Hydrogels/chemistry ; Hydrogen-Ion Concentration ; Kinetics ; Nickel/chemistry ; *Polysaccharides, Bacterial/chemistry ; Solutions ; Water/chemistry ; *Water Pollutants, Chemical/chemistry/isolation &amp; purification ; Water Purification/methods ; }, abstract = {This study aimed to fabricate a series of biodegradable hydrogel films by gelating/physically crosslinking a blend of xanthan gum (XG) and chitosan (CS) in various combinations using a facile, green, and low cost solution casting technique. The adsorption of Cd[2+], Cu[2+] and Ni[2+] by the XG/CS biofilm in aqueous solution was studied in batch experiments to determine how the pH of the solution, contact time, dosage of adsorbent, initial metal ion concentration and ionic strength affect its adsorption. A highly pH-dependent adsorption process was observed for three metal ions. A maximum amount of Cd[2+], Ni[2+], and Cu[2+] ions was adsorbable with 50 mg of the adsorbent at pH 6.0 for an initial metal concentration of 50 mg.L[-1]. An empirical pseudo-second-order model seems to fit the kinetic experimental data reasonably well. It was found that the Langmuir model correlated better with equilibrium isotherm when compared with the Freundlich model. For Cd[2+], Ni[2+], and Cu[2+] ions at 25 °C, the maximum monolayer adsorption capacity was 152.33, 144.79, and 139.71 mg.g[-1], respectively. Furthermore, the biofilm was capable of regenerating, allowing metal ions to adsorb and desorb for five consecutive cycles. Therefore, the developed biodegradable film offers the potential for remediation of specified metal ions.}, }
@article {pmid38582122, year = {2024}, author = {Chen, X and Yang, G and Quan, X and Zhu, S and Qin, B and Shou, D and Zhuang, L}, title = {Significance of a minor pilin PilV in biofilm cohesion of Geobacter sulfurreducens.}, journal = {The Science of the total environment}, volume = {927}, number = {}, pages = {172242}, doi = {10.1016/j.scitotenv.2024.172242}, pmid = {38582122}, issn = {1879-1026}, mesh = {*Geobacter/physiology/genetics ; *Biofilms ; *Fimbriae Proteins/genetics/metabolism ; *Bacterial Adhesion ; Fimbriae, Bacterial/physiology/metabolism ; Bioelectric Energy Sources ; }, abstract = {Bacterial adhesion plays a vital role in forming and shaping the structure of electroactive biofilms that are essential for the performance of bioelectrochemical systems (BESs). Type IV pili are known to mediate cell adhesion in many Gram-negative bacteria, but the mechanism of pili-mediated cell adhesion of Geobacter species on anode surface remains unclear. Herein, a minor pilin PilV2 was found to be essential for cell adhesion ability of Geobacter sulfurreducens since the lack of pilV2 gene depressed the cell adhesion capability by 81.2% in microplate and the anodic biofilm density by 23.1 % at -0.1 V and 37.7 % at -0.3 V in BESs. The less cohesiveness of mutant biofilms increased the charge transfer resistance and biofilm resistance, which correspondingly lowered current generation of the pilV2-deficient strain by up to 63.2 % compared with that of the wild-type strain in BESs. The deletion of pilV2 posed an insignificant effect on the production of extracellular polysaccharides, pili, extracellular cytochromes and electron shuttles that are involved in biofilm formation or extracellular electron transfer (EET) process. This study demonstrated the significance of pilV2 gene in cell adhesion and biofilm formation of G. sulfurreducens, as well as the importance of pili-mediated adhesion for EET of electroactive biofilm.}, }
@article {pmid38581872, year = {2024}, author = {Niu, C and Zhao, X and Shi, D and Ying, Y and Wu, M and Lai, CY and Guo, J and Hu, S and Liu, T}, title = {Bioreduction of chromate in a syngas-based membrane biofilm reactor.}, journal = {Journal of hazardous materials}, volume = {470}, number = {}, pages = {134195}, doi = {10.1016/j.jhazmat.2024.134195}, pmid = {38581872}, issn = {1873-3336}, mesh = {*Bioreactors ; *Chromates/metabolism ; *Biofilms ; *Membranes, Artificial ; Fermentation ; Water Pollutants, Chemical/metabolism ; Oxidation-Reduction ; Fatty Acids, Volatile/metabolism ; Bacteria/metabolism/genetics ; Hydrogen/metabolism ; Gases/metabolism ; Biodegradation, Environmental ; }, abstract = {This study leveraged synthesis gas (syngas), a renewable resource attainable through the gasification of biowaste, to achieve efficient chromate removal from water. To enhance syngas transfer efficiency, a membrane biofilm reactor (MBfR) was employed. Long-term reactor operation showed a stable and high-level chromate removal efficiency > 95%, yielding harmless Cr(III) precipitates, as visualised by scanning electron microscopy and energy dispersive X-ray analysis. Corresponding to the short hydraulic retention time of 0.25 days, a high chromate removal rate of 80 µmol/L/d was attained. In addition to chromate reduction, in situ production of volatile fatty acids (VFAs) by gas fermentation was observed. Three sets of in situ batch tests and two groups of ex situ batch tests jointly unravelled the mechanisms, showing that biological chromate reduction was primarily driven by VFAs produced from in situ syngas fermentation, whereas hydrogen originally present in the syngas played a minor role. 16 S rRNA gene amplicon sequencing has confirmed the enrichment of syngas-fermenting bacteria (such as Sporomusa), who performed in situ gas fermentation leading to the synthesis of VFAs, and organics-utilising bacteria (such as Aquitalea), who utilised VFAs to drive chromate reduction. These findings, combined with batch assays, elucidate the pathways orchestrating synergistic interactions between fermentative microbial cohorts and chromate-reducing microorganisms. The findings facilitate the development of cost-effective strategies for groundwater and drinking water remediation and present an alternative application scenario for syngas.}, }
@article {pmid38578301, year = {2024}, author = {Labadie, M and Marchal, F and Merbahi, N and Girbal-Neuhauser, E and Fontagné-Faucher, C and Marcato-Romain, CE}, title = {Cell density and extracellular matrix composition mitigate bacterial biofilm sensitivity to UV-C LED irradiation.}, journal = {Applied microbiology and biotechnology}, volume = {108}, number = {1}, pages = {286}, pmid = {38578301}, issn = {1432-0614}, support = {12050475//R&#xe9;gion Occitanie Pyr&#xe9;n&#xe9;es-M&#xe9;diterran&#xe9;e/ ; }, mesh = {*Disinfection ; *Biofilms ; Extracellular Matrix ; Bacteria ; Extracellular Polymeric Substance Matrix ; Pseudomonas aeruginosa ; }, abstract = {Ultraviolet-C light-emitting diodes (UV-C LEDs) are an emerging technology for decontamination applications in different sectors. In this study, the inactivation of bacterial biofilms was investigated by applying an UV-C LED emitting at 280 nm and by measuring both the influence of the initial cell density (load) and presence of an extracellular matrix (biofilm). Two bacterial strains exposing diverging matrix structures and biochemical compositions were used: Pseudomonas aeruginosa and Leuconostoc citreum. UV-C LED irradiation was applied at three UV doses (171 to 684 mJ/cm[2]) on both surface-spread cells and on 24-h biofilms and under controlled cell loads, and bacterial survival was determined. All surface-spread bacteria, between 10[5] and 10[9] CFU/cm[2], and biofilms at 10[8] CFU/cm[2] showed that bacterial response to irradiation was dose-dependent. The treatment efficacy decreased significantly for L. citreum surface-spread cells when the initial cell load was high, while no load effect was observed for P. aeruginosa. Inactivation was also reduced when bacteria were grown under a biofilm form, especially for P. aeruginosa: a protective effect could be attributed to abundant extracellular DNA and proteins in the matrix of P. aeruginosa biofilms, as revealed by Confocal Laser Scanning Microscopy observations. This study showed that initial cell load and exopolymeric substances are major factors influencing UV-C LED antibiofilm treatment efficacy. KEY POINTS: • Bacterial cell load (CFU/cm[2]) could impact UV-C LED irradiation efficiency • Characteristics of the biofilm matrix have a paramount importance on inactivation • The dose to be applied can be predicted based on biofilm properties.}, }
@article {pmid38578180, year = {2024}, author = {Puca, V and Marinacci, B and Pellegrini, B and Campanile, F and Santagati, M and Grande, R}, title = {Biofilm and bacterial membrane vesicles: recent advances.}, journal = {Expert opinion on therapeutic patents}, volume = {34}, number = {6}, pages = {475-491}, doi = {10.1080/13543776.2024.2338101}, pmid = {38578180}, issn = {1744-7674}, mesh = {*Biofilms/drug effects ; *Patents as Topic ; Humans ; *Bacterial Infections/microbiology/drug therapy ; *Bacteria ; Animals ; *Anti-Bacterial Agents/pharmacology ; Extracellular Vesicles/metabolism ; Drug Development ; Virulence ; }, abstract = {INTRODUCTION: Bacterial Membrane Vesicles (MVs) play important roles in cell-to-cell communication and transport of several molecules. Such structures are essential components of Extracellular Polymeric Substances (EPS) biofilm matrix of many bacterial species displaying a structural function and a role in virulence and pathogenesis.<br><br>AREAS COVERED: In this review were included original articles from the last ten years by searching the keywords 'biofilm' and 'vesicles' on PUBMED and Scopus databases. The articles available in literature mainly describe a positive correlation between bacterial MVs and biofilms formation. The research on Espacenet and Google Patent databases underlines the available patents related to the application of both biofilm MVs and planktonic MVs in inhibiting biofilm formation.<br><br>EXPERT OPINION: This review covers and analyzes recent advances in the study of the relationship between bacterial vesicles and biofilm. The huge number of papers discussing the role of MVs confirms the interest aimed at developing new applications in the medical field. The study of the MVs composition and biogenesis may contribute to the identification of components which could be (i) the target for the development of new drugs inhibiting the biofilm establishment; (ii) candidates for the development of vaccines; (iii) biomarkers for the diagnosis of bacterial infections.}, }
@article {pmid38577556, year = {2024}, author = {Li, X and Zhang, X and Zhang, M and Luo, X and Zhang, T and Liu, X and Lu, R and Zhang, Y}, title = {Environmental magnesium ion affects global gene expression, motility, biofilm formation and virulence of Vibrio parahaemolyticus.}, journal = {Biofilm}, volume = {7}, number = {}, pages = {100194}, pmid = {38577556}, issn = {2590-2075}, abstract = {Vibrio parahaemolyticus is widely distributed in marine ecosystems. Magnesium ion (Mg[2+]) is the second most abundant metal cation in seawater, and plays important roles in the growth and gene expression of V. parahaemolyticus, but lacks the detailed mechanisms. In this study, the RNA sequencing data demonstrated that a total of 1494 genes was significantly regulated by Mg[2+]. The majority of the genes associated with lateral flagella, exopolysaccharide, type III secretion system 2, type VI secretion system (T6SS) 1, T6SS2, and thermostable direct hemolysin were downregulated. A total of 18 genes that may be involved in c-di-GMP metabolism and more than 80 genes encoding putative regulators were also significantly and differentially expressed in response to Mg[2+], indicating that the adaptation process to Mg[2+] stress may be strictly regulated by complex regulatory networks. In addition, Mg[2+] promoted the proliferative speed, swimming motility and cell adhesion of V. parahaemolyticus, but inhibited the swarming motility, biofilm formation, and c-di-GMP production. However, Mg[2+] had no effect on the production of capsular polysaccharide and cytoxicity against HeLa cells. Therefore, Mg[2+] had a comprehensive impact on the physiology and gene expression of V. parahaemolyticus.}, }
@article {pmid38575495, year = {2024}, author = {Condado Huerta, MCC and Antunez-Mojica, M and Martínez Plascencia, H and Barrera Molina, AI}, title = {[Agave fructanos promote in vitro biofilm formation with a probiotic consortium Lactobacillus delbrueckii ssp. lactis, L. delbrueckii ssp. bulgaricus and Streptococcus thermophilus].}, journal = {Revista Argentina de microbiologia}, volume = {56}, number = {3}, pages = {322-328}, doi = {10.1016/j.ram.2024.02.002}, pmid = {38575495}, issn = {0325-7541}, mesh = {*Biofilms/growth &amp; development/drug effects ; *Lactobacillus delbrueckii/physiology ; *Streptococcus thermophilus/physiology ; *Probiotics ; *Fructans/pharmacology ; *Agave/microbiology ; Microbial Consortia/physiology ; }, abstract = {In recent years the relationship between the intestinal microbiota, the host and chronic non-communicable diseases has brought interest into the study of its formation and maintenance in the host. Lactic acid bacteria (BAL) are Gram-positive bacteria with probiotic activity, which have been associated with many health benefits, such as decreased body fat mass and lower risk of type II diabetes mellitus. One of the main colonization mechanisms and bacteria survival strategies is the production of biofilms and the use of prebiotics as substrates to achieve a balance within intestinal microbiota. However, there is not enough evidence to demonstrate the biofilm formation in the presence of agave fructans (AF). This study aimed to evaluate in vitro the biofilm formation in a consortium of lactic acid bacteria: Lactobacillus delbrueckii ssp. lactis, Lactobacillus delbrueckii ssp. bulgaricus y Streptococcus thermophilus in the presence of AF at different concentrations: 0%, 0,1%, 4%, 8% y 16%. The addition of 0,1% of AF correlates with the best capacity for biofilm formation. The findings imply the possibility of modulating the biofilm formation of lactic acid bacteria with AF. These results can contribute positively to the host, by generating intestinal homeostasis, colonization resistance, stability to food digestion and chemical modifications of drugs and carry out beneficial functions to the health.}, }
@article {pmid38575095, year = {2024}, author = {Liu, W and Qian, J and Ding, H and Li, J and Liu, J and Zhou, W}, title = {Synergistic interactions of light and dark biofilms in rotating algal biofilm system for enhanced aquaculture wastewater treatment.}, journal = {Bioresource technology}, volume = {400}, number = {}, pages = {130654}, doi = {10.1016/j.biortech.2024.130654}, pmid = {38575095}, issn = {1873-2976}, mesh = {*Biofilms ; *Aquaculture/methods ; *Wastewater/microbiology ; Nitrogen ; Phosphorus ; Water Purification/methods ; Light ; Biomass ; Waste Disposal, Fluid/methods ; Bacteria/metabolism ; Denitrification ; }, abstract = {Aquaculture wastewater management is critical for environmental sustainability. This study investigates the synergistic interactions between light and dark biofilms with a Rotating Algal Biofilm (RAB) system for effective aquaculture wastewater treatment. The RAB system, optimized with a 5-day harvest time and 12-hour hydraulic retention time, demonstrated superior biomass productivity (3.3 g m[-2] d[-1]) and total ammoniacal nitrogen removal (82.3 %). Comparative analysis of light and dark biofilms revealed their complementary roles, with the light side exhibiting higher carbon assimilation and nutrient removal efficiencies, while the dark side contributed significantly to denitrification and phosphorus removal. Microbial community analysis highlighted the dominance of key bacterial genera such as Haliangium, Methyloversatilis and Comamonadaceae, along with the algal genus Chlorella, indicating their crucial roles in nutrient cycling. This study provides insights into the operational dynamics of RAB system for sustainable aquaculture wastewater treatment.}, }
@article {pmid38573831, year = {2024}, author = {Machado, MAM and Chapartegui-González, I and Castro, VS and Figueiredo, EES and Conte-Junior, CA and Torres, AG}, title = {Biofilm-producing Escherichia coli O104:H4 overcomes bile salts toxicity by expressing virulence and resistance proteins.}, journal = {Letters in applied microbiology}, volume = {77}, number = {4}, pages = {}, doi = {10.1093/lambio/ovae032}, pmid = {38573831}, issn = {1472-765X}, support = {200472/2022-4//CNPq/ ; //UTMB/ ; }, mesh = {Animals ; Humans ; Escherichia coli/metabolism ; *Escherichia coli O104 ; Virulence ; Caco-2 Cells ; Chromatography, Liquid ; Tandem Mass Spectrometry ; Biofilms ; *Escherichia coli Infections/microbiology ; *Shiga-Toxigenic Escherichia coli ; *Escherichia coli Proteins/genetics/metabolism ; }, abstract = {We investigated bile salts' ability to induce phenotypic changes in biofilm production and protein expression of pathogenic Escherichia coli strains. For this purpose, 82 pathogenic E. coli strains isolated from humans (n = 70), and animals (n = 12), were examined for their ability to form biofilms in the presence or absence of bile salts. We also identified bacterial proteins expressed in response to bile salts using sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-electrophoresis) and liquid chromatography-mass spectrometry (LC-MS/MS). Lastly, we evaluated the ability of these strains to adhere to Caco-2 epithelial cells in the presence of bile salts. Regarding biofilm formation, two strains isolated from an outbreak in Republic of Georgia in 2009 were the only ones that showed a high and moderate capacity to form biofilm in the presence of bile salts. Further, we observed that those isolates, when in the presence of bile salts, expressed different proteins identified as outer membrane proteins (i.e. OmpC), and resistance to adverse growth conditions (i.e. F0F1, HN-S, and L7/L12). We also found that these isolates exhibited high adhesion to epithelial cells in the presence of bile salts. Together, these results contribute to the phenotypic characterization of E. coli O104: H4 strains.}, }
@article {pmid38573741, year = {2024}, author = {Padaga, SG and Bhatt, H and Ch, S and Paul, M and Itoo, AM and Ghosh, B and Roy, S and Biswas, S}, title = {Glycol Chitosan-Poly(lactic acid) Conjugate Nanoparticles Encapsulating Ciprofloxacin: A Mucoadhesive, Antiquorum-Sensing, and Biofilm-Disrupting Treatment Modality for Bacterial Keratitis.}, journal = {ACS applied materials &amp; interfaces}, volume = {16}, number = {15}, pages = {18360-18385}, doi = {10.1021/acsami.3c18061}, pmid = {38573741}, issn = {1944-8252}, mesh = {Animals ; Female ; Humans ; Ciprofloxacin/pharmacology ; Chickens ; Biofilms ; Anti-Bacterial Agents/pharmacology ; Polyesters/pharmacology ; Quorum Sensing ; *Nanoparticles ; Bacteria ; *Eye Infections, Bacterial ; *Keratitis ; Pseudomonas aeruginosa ; *Chitosan ; }, abstract = {Bacterial keratitis (BK) causes visual morbidity/blindness if not treated effectively. Here, ciprofloxacin (CIP)-loaded nanoparticles (NPs) using glycol chitosan (GC) and poly(lactic acid) (PLA) conjugate at three different ratios (CIP@GC(PLA) NPs (1:1,5,15)) were fabricated. CIP@GC(PLA) NPs (1:1) were more effective than other tested ratios, indicating the importance of optimal hydrophobic/hydrophilic balance for corneal penetration and preventing bacterial invasion. The CIP@GC(PLA) (NPs) (1:1) realized the highest association with human corneal epithelial cells, which were nonirritant to the hen's egg-chorioallantoic membrane test (HET-CAM test) and demonstrated significant antibacterial response in the in vitro minimum inhibitory, bactericidal, live-dead cells, zone of inhibition, and biofilm inhibition assays against the keratitis-inducing pathogen Pseudomonas aeruginosa. The antiquorum sensing activity of GC has been explored for the first time. The NPs disrupted the bacterial quorum sensing by inhibiting the production of virulence factors, including acyl homoserine lactones, pyocyanin, and motility, and caused significant downregulation of quorum sensing associated genes. In the in vivo studies, CIP@GC(PLA) NPs (1:1) displayed ocular retention in vivo (∼6 h) and decreased the opacity and the bacterial load effectively. Overall, the CIP@GC(PLA) NP (1:1) is a biofilm-disrupting antiquorum sensing treatment regimen with clinical translation potential in BK.}, }
@article {pmid38572100, year = {2024}, author = {Fan, D and Liu, X and Ren, Y and Luo, Z and Li, Y and Dong, J and Wegner, SV and Chen, F and Zeng, W}, title = {Harnessing antimicrobial peptide-coupled photosensitizer to combat drug-resistant biofilm infections through enhanced photodynamic therapy.}, journal = {Acta pharmaceutica Sinica. B}, volume = {14}, number = {4}, pages = {1759-1771}, pmid = {38572100}, issn = {2211-3835}, abstract = {Bacterial biofilm-associated infection was one of the most serious threats to human health. However, effective drugs for drug-resistance bacteria or biofilms remain rarely reported. Here, we propose an innovative strategy to develop a multifunctional antimicrobial agent with broad-spectrum antibacterial activity by coupling photosensitizers (PSs) with antimicrobial peptides (AMPs). This strategy capitalizes on the ability of PSs to generate reactive oxygen species (ROS) and the membrane-targeting property of AMPs (KRWWKWIRW, a peptide screened by an artificial neural network), synergistically enhancing the antimicrobial activity. In addition, unlike conventional aggregation-caused quenching (ACQ) photosensitizers, aggregation-induced emission (AIE) PSs show stronger fluorescence emission in the aggregated state to help visualize the antibacterial mechanism. In vitro antibacterial experiments demonstrated the excellent killing effects of the developed agent against both Gram-positive (G[+]) and Gram-negative (G[-]) bacteria. The bacterial-aggregations induced ability enhanced the photoactivatable antibacterial activity against G[-] bacteria. Notably, it exhibited a significant effect on destroying MRSA biofilms. Moreover, it also showed remarkable efficacy in treating wound infections in mice in vivo. This multifunctional antimicrobial agent holds significant potential in addressing the challenges posed by bacterial biofilm-associated infections and drug-resistant bacteria.}, }
@article {pmid38570017, year = {2024}, author = {Hamion, G and Aucher, W and Mercier, A and Tewes, F and Menard, M and Bertaux, J and Girardot, M and Imbert, C}, title = {Insights into betulinic acid as a promising molecule to fight the interkingdom biofilm Staphylococcus aureus-Candida albicans.}, journal = {International journal of antimicrobial agents}, volume = {63}, number = {6}, pages = {107166}, doi = {10.1016/j.ijantimicag.2024.107166}, pmid = {38570017}, issn = {1872-7913}, mesh = {*Biofilms/drug effects ; *Pentacyclic Triterpenes/pharmacology ; *Betulinic Acid ; *Candida albicans/drug effects ; *Staphylococcus aureus/drug effects ; *Triterpenes/pharmacology/chemistry ; Humans ; Flow Cytometry ; Microbial Sensitivity Tests ; Cell Membrane/drug effects ; Real-Time Polymerase Chain Reaction ; Microscopy ; }, abstract = {The demand for antibiofilm molecules has increased over several years due to their potential to fight biofilm-associated infections, such as those including the interkingdom Staphylococcus aureus-Candida albicans occurring in clinical settings worldwide. Recently, we identified a pentacyclic triterpenoid compound, betulinic acid, from invasive macrophytes, with interesting antibiofilm properties. The aim of the present study was to provide insights into the mechanism of action of betulinic acid against the clinically relevant bi-species S. aureus-C. albicans biofilms. Microscopy examinations, flow cytometry and crystal violet assays confirmed that betulinic acid was effective at damaging mature S. aureus-C. albicans biofilms or inhibiting their formation, reducing biofilm biomass by 70% on average and without microbicidal activity. The results suggested an action of betulinic acid on cell membranes, inducing changes in properties such as composition, hydrophobicity and fluidity as observed in C. albicans, which may hinder the early adhesion step, biofilm growth and the physical interactions of both microbial species. Further results of real-time polymerase chain reaction argued in favour of a reduction in S. aureus-C. albicans physical interaction due to betulinic acid by the modulation of biofilm-related gene expression, as observed in early stages of biofilm formation. This study revealed the potential of betulinic acid as a candidate agent for the prevention and treatment of S. aureus-C. albicans biofilm-related infections.}, }
@article {pmid38569307, year = {2024}, author = {Yu, Z and Qiu, D and Zhou, T and Zeng, L and Yan, C}, title = {Biofilm enhances the interactive effects of microplastics and oxytetracycline on zebrafish intestine.}, journal = {Aquatic toxicology (Amsterdam, Netherlands)}, volume = {270}, number = {}, pages = {106905}, doi = {10.1016/j.aquatox.2024.106905}, pmid = {38569307}, issn = {1879-1514}, mesh = {Animals ; *Oxytetracycline/toxicity ; Microplastics/toxicity ; Plastics ; Zebrafish ; *Water Pollutants, Chemical/toxicity ; Anti-Bacterial Agents/toxicity ; Intestines ; }, abstract = {The enhanced adsorption of pollutants on biofilm-developed microplastics has been proved in many studies, but the ecotoxicological effects of biofilm-developed microplastics on organisms are still unclear. In this study, adult zebrafish were exposed to original microplastics, biofilm-developed microplastics, original microplastics absorbed with oxytetracycline (OTC), and biofilm-developed microplastics absorbed with OTC for 30 days. The intestinal histological damage, intestinal biomarker response, gut microbiome and antibiotic resistance genes (ARGs) profile of zebrafish were measured to explore the roles of biofilm in the effects of microplastics. The results showed that biofilm-developed microplastics significantly increased the number of goblet cells in intestinal epithelium compared with the control group. The biofilm-developed microplastics also induced the oxidative response in the zebrafish intestines, and biofilm changed the response mode in the combined treatment with OTC. Additionally, the biofilm-developed microplastics caused intestinal microbiome dysbiosis, and induced the abundance of some pathogenic genera increasing by several times compared with the control group and the original microplastics treatments, regardless of OTC adsorption. Furthermore, the abundance of ARGs in biofilm-developed microplastics increased significantly compared with the control and the original microplastic treatments. This study emphasized the significant influence and unique role of biofilm in microplastic studies.}, }
@article {pmid38565849, year = {2024}, author = {Cao, L and Tan, J and Zhang, Z and Lin, B and Mu, Y and Jiang, M and Jiang, Y and Huang, X and Han, L}, title = {Discovery of Antifungal Norsesquiterpenoids from a Soil-Derived Streptomyces microflavus: Targeting Biofilm Formation and Synergistic Combination with Amphotericin B against Yeast-like Fungi.}, journal = {Journal of agricultural and food chemistry}, volume = {72}, number = {15}, pages = {8521-8535}, doi = {10.1021/acs.jafc.3c08707}, pmid = {38565849}, issn = {1520-5118}, mesh = {*Antifungal Agents/pharmacology ; Amphotericin B/pharmacology ; Candida albicans ; *Streptomyces/genetics ; Biofilms ; Microbial Sensitivity Tests ; }, abstract = {Thirty-five norsesquiterpenoids were isolated from the fermentation broth of Streptomyces microflavus from the forest soil of Ailaoshan in China. The structures of new compounds (1-5, 10-26) were elucidated by comprehensive spectroscopic analysis including data from experimental and calculated ECD spectra, as well as Mosher's reagent derivatives method. Norsesquiterpenoids showed different levels of antifungal activity with MIC80 values ranging from 25 to 200 μg/mL against Candida albicans, Candida parapsilosis, and Cryptococcus neoformans. The combining isolated norsesquiterpenoids with amphotericin B resulted in a synergistic interaction against test yeast-like fungi with a fractional inhibitory concentration index < 0.5. Compound 33 significantly inhibited biofilm formation and destroyed the preformed biofilm of fungi. Moreover, 33 downregulated the expression of adhesion-related genes HWP1, ALS1, ALS3, ECE1, EAP1, and BCR1 to inhibit the adhesion of C. albicans. Findings from the current study highlight the potential usage of norsesquiterpenoids from soil-derived Streptomyces for antifungal leads discovery.}, }
@article {pmid38565843, year = {2024}, author = {Brar, NK and Dhariwal, A and Åmdal, HA and Junges, R and Salvadori, G and Baker, JL and Edlund, A and Petersen, FC}, title = {Exploring ex vivo biofilm dynamics: consequences of low ampicillin concentrations on the human oral microbiome.}, journal = {NPJ biofilms and microbiomes}, volume = {10}, number = {1}, pages = {37}, pmid = {38565843}, issn = {2055-5008}, support = {K99 DE029228/DE/NIDCR NIH HHS/United States ; R00 DE029228/DE/NIDCR NIH HHS/United States ; }, mesh = {Humans ; *Anti-Bacterial Agents/pharmacology/therapeutic use ; Ampicillin/pharmacology ; *Microbiota ; Bacteria/genetics ; Biofilms ; }, abstract = {Prolonged exposure to antibiotics at low concentration can promote processes associated with bacterial biofilm formation, virulence and antibiotic resistance. This can be of high relevance in microbial communities like the oral microbiome, where commensals and pathogens share a common habitat and where the total abundance of antibiotic resistance genes surpasses the abundance in the gut. Here, we used an ex vivo model of human oral biofilms to investigate the impact of ampicillin on biofilm viability. The ecological impact on the microbiome and resistome was investigated using shotgun metagenomics. The results showed that low concentrations promoted significant shifts in microbial taxonomic profile and could enhance biofilm viability by up to 1 to 2-log. For the resistome, low concentrations had no significant impact on antibiotic resistance gene (ARG) diversity, while ARG abundance decreased by up to 84%. A positive correlation was observed between reduced microbial diversity and reduced ARG abundance. The WHO priority pathogens Streptococcus pneumoniae and Staphylococcus aureus were identified in some of the samples, but their abundance was not significantly altered by ampicillin. Most of the antibiotic resistance genes that increased in abundance in the ampicillin group were associated with streptococci, including Streptococcus mitis, a well-known potential donor of ARGs to S. pneumoniae. Overall, the results highlight the potential of using the model to further our understanding of ecological and evolutionary forces driving antimicrobial resistance in oral microbiomes.}, }
@article {pmid38564677, year = {2024}, author = {Weaver, AA and Jia, J and Cutri, AR and Madukoma, CS and Vaerewyck, CM and Bohn, PW and Shrout, JD}, title = {Alkyl quinolones mediate heterogeneous colony biofilm architecture that improves community-level survival.}, journal = {Journal of bacteriology}, volume = {206}, number = {4}, pages = {e0009524}, pmid = {38564677}, issn = {1098-5530}, support = {R01 AI113219/AI/NIAID NIH HHS/United States ; UM1 TR004402/TR/NCATS NIH HHS/United States ; }, mesh = {Humans ; *Quinolones/metabolism ; Biofilms ; *Pseudomonas Infections/microbiology ; Virulence ; Pseudomonas aeruginosa/metabolism ; }, abstract = {Bacterial communities exhibit complex self-organization that contributes to their survival. To better understand the molecules that contribute to transforming a small number of cells into a heterogeneous surface biofilm community, we studied acellular aggregates, structures seen by light microscopy in Pseudomonas aeruginosa colony biofilms using light microscopy and chemical imaging. These structures differ from cellular aggregates, cohesive clusters of cells important for biofilm formation, in that they are visually distinct from cells using light microscopy and are reliant on metabolites for assembly. To investigate how these structures benefit a biofilm community we characterized three recurrent types of acellular aggregates with distinct geometries that were each abundant in specific areas of these biofilms. Alkyl quinolones (AQs) were essential for the formation of all aggregate types with AQ signatures outside the aggregates below the limit of detection. These acellular aggregates spatially sequester AQs and differentiate the biofilm space. However, the three types of aggregates showed differing properties in their size, associated cell death, and lipid content. The largest aggregate type co-localized with spatially confined cell death that was not mediated by Pf4 bacteriophage. Biofilms lacking AQs were absent of localized cell death but exhibited increased, homogeneously distributed cell death. Thus, these AQ-rich aggregates regulate metabolite accessibility, differentiate regions of the biofilm, and promote survival in biofilms.IMPORTANCEPseudomonas aeruginosa is an opportunistic pathogen with the ability to cause infection in the immune-compromised. It is well established that P. aeruginosa biofilms exhibit resilience that includes decreased susceptibility to antimicrobial treatment. This work examines the self-assembled heterogeneity in biofilm communities studying acellular aggregates, regions of condensed matter requiring alkyl quinolones (AQs). AQs are important to both virulence and biofilm formation. Aggregate structures described here spatially regulate the accessibility of these AQs, differentiate regions of the biofilm community, and despite their association with autolysis, correlate with improved P. aeruginosa colony biofilm survival.}, }
@article {pmid38564153, year = {2024}, author = {K, S and Nechikkadan, S and Theresa, M and Krishnankutty, RE}, title = {ZnO nanoparticles induced biofilm formation in Klebsiella pneumoniae and Staphylococcus aureus at sub-inhibitory concentrations.}, journal = {Folia microbiologica}, volume = {69}, number = {6}, pages = {1175-1183}, pmid = {38564153}, issn = {1874-9356}, mesh = {*Biofilms/drug effects/growth &amp; development ; *Zinc Oxide/pharmacology/chemistry ; *Klebsiella pneumoniae/drug effects/physiology/growth &amp; development ; *Staphylococcus aureus/drug effects/physiology ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology ; Metal Nanoparticles/chemistry ; Microscopy, Atomic Force ; Nanoparticles/chemistry ; }, abstract = {Biofilm formation by the pathogenic bacteria generates a serious threat to the public health as it can increase the virulence potential, resistance to drugs, and escape from the host immune response mechanisms. Among the environmental factors that influence the biofilm formation, there are only limited reports available on the role of antimicrobial agents. During the antimicrobial drug administration or application for any purpose, the microbial population can expect to get exposed to the sub-minimum inhibitory concentration (sub-MIC) of the drug which will have an unprecedented impact on microbial responses. Hence, the study has been conducted to investigate the effects of sub-MIC levels of zinc oxide nanoparticles (ZnO NPs) on the biofilm formation of Klebsiella pneumoniae and Staphylococcus aureus. Here, the selected bacteria were primarily screened for the biofilm formation by using the Congo red agar method, and their susceptibility to ZnO NPs was also evaluated. Quantitative difference in biofilm formation by the selected organisms in the presence of ZnO NPs at the sub-MIC level was further carried out by using the microtiter plate-crystal violet assay. Further, the samples were subjected to atomic force microscopy (AFM) analysis to evaluate the properties and pattern of the biofilm modulated under the experimental conditions used. From these, the organisms treated with sub-MIC levels of ZnO NPs were found to have enhanced biofilm formation when compared with the untreated sample. Also, no microbial growth could be observed for the samples treated with the minimum inhibitory concentration (MIC) of ZnO NPs. The results observed in the study provide key insights into the impact of nanomaterials on clinically important microorganisms which demands critical thinking on the antimicrobial use of nanomaterials.}, }
@article {pmid38564110, year = {2024}, author = {Ben-Amram, H and Azrad, M and Cohen-Assodi, J and Sharabi-Nov, A and Edelstein, S and Agay-Shay, K and Peretz, A}, title = {Biofilm Formation by Hospital-Acquired Resistant Bacteria Isolated from Respiratory Samples.}, journal = {Journal of epidemiology and global health}, volume = {14}, number = {2}, pages = {291-297}, pmid = {38564110}, issn = {2210-6014}, mesh = {*Biofilms/drug effects ; Humans ; Female ; Male ; *Cross Infection/microbiology ; Middle Aged ; Aged ; Adult ; Israel/epidemiology ; Anti-Bacterial Agents/therapeutic use/pharmacology ; Microbial Sensitivity Tests ; Aged, 80 and over ; Methicillin-Resistant Staphylococcus aureus/isolation &amp; purification ; Young Adult ; Respiratory Tract Infections/microbiology/drug therapy ; }, abstract = {BACKGROUND: Hospital-acquired resistant infections (HARI) are infections, which develop 48 h or more after admission to a healthcare facility. HARI pose a considerably acute challenge, due to limited treatment options. These infections are associated bacterial biofilms, which act as a physical barrier to diverse external stresses, such as desiccation, antimicrobials and biocides. We assessed the influence of multiple factors on biofilm production by HARI -associated bacteria.<br><br>METHODS: Bacteria were isolated from samples of patients with respiratory HARI who were hospitalized during 2020-2022 in north Israel. Following antibiotic susceptibility testing by disc diffusion or broth microdilution, biofilm formation capacities of resistant bacteria (methicillin-resistant staphylococcus aureus, extended spectrum beta-lactamase-producing Escherichia coli and Klebsiela pneumonia, and multidrug-resistant Pseudomonas aeruginosa and Acinetobacter baumannii) was assessed using the crystalline violet staining method. Data regarding season, time to infection, bacterial species, patient age and gender, year, and medical department were collected from the patient medical records.<br><br>RESULTS: Among the 226 study isolates, K. pneumonia was the most prevalent (35.4%) bacteria, followed by P. aeruginosa (23.5%), and methicillin-resistant staphylococcus aureus (MRSA) (21.7%). A significantly higher rate of HARI was documented in 2022 compared to 2020-2021. The majority of isolates (63.3%) were strong biofilm producers, with K. pneumonia (50.3%) being most dominant, followed by P. aeruginosa (29.4%). Biofilm production strength was significantly affected by seasonality and hospitalization length, with strong biofilm production in autumn and in cases where hospitalization length exceeded 30&#xa0;days.<br><br>CONCLUSION: Biofilm production by HARI bacteria is influenced by bacterial species, season and hospitalization length.}, }
@article {pmid38562404, year = {2024}, author = {Wang, Y and Li, C and Zhang, H and Chi, Y and Cai, Y}, title = {The Potentiation Activity of Azithromycin in Combination with Colistin or Levofloxacin Against Pseudomonas aeruginosa Biofilm Infection.}, journal = {Infection and drug resistance}, volume = {17}, number = {}, pages = {1259-1266}, pmid = {38562404}, issn = {1178-6973}, abstract = {OBJECTIVE: Pseudomonas aeruginosa (PA) often displays drug resistance and biofilm-mediated adaptability. Here, we aimed to evaluate the antibiofilm efficacy of azithromycin-based combination regimens.<br><br>METHODS: Minimum inhibitory concentrations (MICs), minimal biofilm eradication concentrations (MBECs), and MBEC-combination of azithromycin, colistin, amikacin, and levofloxacin to bioluminescent strain PAO1 and carbapenem-resistant PAO1 (CRPAO1) were assessed. An animal biofilm infection model was established and detected using a live animal bio-photonic imaging system.<br><br>RESULTS: In vitro, PAO1 and CRPAO1 were susceptible to colistin, amikacin, and levofloxacin, while they were unsusceptible to azithromycin. The combinations based on azithromycin have no synergistic effect on biofilm in vitro. In vivo, azithromycin plus colistin or levofloxacin could shorten the PAO1 biofilm eradication time, which totally eradicates the biofilm in all mice on the 8[th] or 6[th] day, while monotherapy only eradicate biofilm in 70% or 80% mice on the 8[th] day. For CRPAO1 biofilm, only azithromycin-colistin combination and colistin monotherapy eradicated the bacteria in 60% and 40% of mice at the 6[th] day.<br><br>CONCLUSION: Azithromycin-based combinations containing levofloxacin or colistin had no synergistic effect in vitro, and they are promising for clinical applications due to the good synergistic activity against PAO1 biofilms in vivo.}, }
@article {pmid38561125, year = {2024}, author = {Castagnini, D and Palma, K and Jara-Wilde, J and Navarro, N and González, MJ and Toledo, J and Canales-Huerta, N and Scavone, P and Härtel, S}, title = {Proteus mirabilis biofilm expansion microscopy yields over 4-fold magnification for super-resolution of biofilm structure and subcellular DNA organization.}, journal = {Journal of microbiological methods}, volume = {220}, number = {}, pages = {106927}, doi = {10.1016/j.mimet.2024.106927}, pmid = {38561125}, issn = {1872-8359}, mesh = {*Proteus mirabilis/chemistry ; *Biofilms ; Bacteria ; DNA ; Microscopy, Fluorescence ; }, abstract = {Bacterial biofilms form when bacteria attach to surfaces and generate an extracellular matrix that embeds and stabilizes a growing community. Detailed visualization and quantitative analysis of biofilm architecture by optical microscopy are limited by the law of diffraction. Expansion Microscopy (ExM) is a novel Super-Resolution technique where specimens are physically enlarged by a factor of ∼4, prior to observation by conventional fluorescence microscopy. ExM requires homogenization of rigid constituents of biological components by enzymatic digestion. We developed an ExM approach capable of expanding 48-h old Proteus mirabilis biofilms 4.3-fold (termed PmbExM), close to the theoretic maximum expansion factor without gross shape distortions. Our protocol, based on lytic and glycoside-hydrolase enzymatic treatments, degrades rigid components in bacteria and extracellular matrix. Our results prove PmbExM to be a versatile and easy-to-use Super-Resolution approach for enabling studies of P. mirabilis biofilm architecture, assembly, and even intracellular features, such as DNA organization.}, }
@article {pmid38561094, year = {2024}, author = {Breen, SKJ and Harper, M and López-Causapé, C and Rogers, KE and Tait, JR and Smallman, TR and Lang, Y and Lee, WL and Zhou, J and Zhang, Y and Bulitta, JB and Nation, RL and Oliver, A and Boyce, JD and Landersdorfer, CB}, title = {Synergistic effects of inhaled aztreonam plus tobramycin on hypermutable cystic fibrosis Pseudomonas aeruginosa isolates in a dynamic biofilm model evaluated by mechanism-based modelling and whole genome sequencing.}, journal = {International journal of antimicrobial agents}, volume = {63}, number = {6}, pages = {107161}, doi = {10.1016/j.ijantimicag.2024.107161}, pmid = {38561094}, issn = {1872-7913}, mesh = {*Tobramycin/administration &amp; dosage/pharmacology ; *Aztreonam/pharmacology/administration &amp; dosage ; *Pseudomonas aeruginosa/drug effects/genetics ; *Biofilms/drug effects ; *Cystic Fibrosis/microbiology/complications ; Humans ; *Anti-Bacterial Agents/pharmacology/administration &amp; dosage/pharmacokinetics/therapeutic use ; Administration, Inhalation ; *Pseudomonas Infections/drug therapy/microbiology ; *Whole Genome Sequencing ; *Drug Synergism ; Microbial Sensitivity Tests ; Drug Resistance, Multiple, Bacterial/genetics ; Models, Theoretical ; Drug Therapy, Combination ; }, abstract = {OBJECTIVE: Hypermutable Pseudomonas aeruginosa strains are highly prevalent in chronic lung infections of patients with cystic fibrosis (CF). Acute exacerbations of these infections have limited treatment options. This study aimed to investigate inhaled aztreonam and tobramycin against clinical hypermutable P. aeruginosa strains using the CDC dynamic in vitro biofilm reactor (CBR), mechanism-based mathematical modelling (MBM) and genomic studies.<br><br>METHODS: Two CF multidrug-resistant strains were investigated in a 168 h CBR (n = 2 biological replicates). Regimens were inhaled aztreonam (75 mg 8-hourly) and tobramycin (300 mg 12-hourly) in monotherapies and combination. The simulated pharmacokinetic profiles of aztreonam and tobramycin (t1/2 = 3 h) were based on published lung fluid concentrations in patients with CF. Total viable and resistant counts were determined for planktonic and biofilm bacteria. MBM of total and resistant bacterial counts and whole genome sequencing were completed.<br><br>RESULTS: Both isolates showed reproducible bacterial regrowth and resistance amplification for the monotherapies by 168 h. The combination performed synergistically, with minimal resistant subpopulations compared to the respective monotherapies at 168 h. Mechanistic synergy appropriately described the antibacterial effects of the combination regimen in the MBM. Genomic analysis of colonies recovered from monotherapy regimens indicated noncanonical resistance mechanisms were likely responsible for treatment failure.<br><br>CONCLUSION: The combination of aztreonam and tobramycin was required to suppress the regrowth and resistance of planktonic and biofilm bacteria in all biological replicates of both hypermutable multidrug-resistant P. aeruginosa CF isolates. The developed MBM could be utilised for future investigations of this promising inhaled combination.}, }
@article {pmid38559352, year = {2024}, author = {Manohar, P and Loh, B and Turner, D and Tamizhselvi, R and Mathankumar, M and Elangovan, N and Nachimuthu, R and Leptihn, S}, title = {In vitro and in vivo evaluation of the biofilm-degrading Pseudomonas phage Motto, as a candidate for phage therapy.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1344962}, pmid = {38559352}, issn = {1664-302X}, abstract = {Infections caused by Pseudomonas aeruginosa are becoming increasingly difficult to treat due to the emergence of strains that have acquired multidrug resistance. Therefore, phage therapy has gained attention as an alternative to the treatment of pseudomonal infections. Phages are not only bactericidal but occasionally show activity against biofilm as well. In this study, we describe the Pseudomonas phage Motto, a T1-like phage that can clear P. aeruginosa infections in an animal model and also exhibits biofilm-degrading properties. The phage has a substantial anti-biofilm activity against strong biofilm-producing isolates (n = 10), with at least a twofold reduction within 24 h. To demonstrate the safety of using phage Motto, cytotoxicity studies were conducted with human cell lines (HEK 293 and RAW 264.7 macrophages). Using a previously established in vivo model, we demonstrated the efficacy of Motto in Caenorhabditis elegans, with a 90% survival rate when treated with the phage at a multiplicity of infection of 10.}, }
@article {pmid38559351, year = {2024}, author = {Liu, H and Ma, J and Yang, P and Geng, F and Li, X and Lü, J and Wang, Y}, title = {Comparative analysis of biofilm characterization of probiotic Escherichia coli.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1365562}, pmid = {38559351}, issn = {1664-302X}, abstract = {Biofilms are thought to play a vital role in the beneficial effects of probiotic bacteria. However, the structure and function of probiotic biofilms are poorly understood. In this work, biofilms of Escherichia coli (E. coli) Nissle 1917 were investigated and compared with those of pathogenic and opportunistic strains (E. coli MG1655, O157:H7) using crystal violet assay, confocal laser scanning microscopy, scanning electron microscopy and FTIR microspectroscopy. The study revealed significant differences in the morphological structure, chemical composition, and spatial heterogeneity of the biofilm formed by the probiotic E. coli strain. In particular, the probiotic biofilm can secrete unique phospholipid components into the extracellular matrix. These findings provide new information on the morphology, architecture and chemical heterogeneity of probiotic biofilms. This information may help us to understand the beneficial effects of probiotics for various applications.}, }
@article {pmid38558539, year = {2024}, author = {Fan, J and Dong, Y and Sun, Y and Ji, Y and Feng, J and Yan, P and Zhu, Y}, title = {Mucus and Biofilm Penetrating Nanoplatform as an Ultrasound-Induced Free Radical Initiator for Targeted Treatment of Helicobacter pylori Infection.}, journal = {Advanced healthcare materials}, volume = {13}, number = {20}, pages = {e2400363}, doi = {10.1002/adhm.202400363}, pmid = {38558539}, issn = {2192-2659}, support = {22208321//National Natural Science Foundation of China/ ; 2022M720130//China Postdoctoral Science Foundation/ ; 232300421058//Natural Science Foundation Outstanding Youth Fund of Henan Province/ ; 24A350018//Key Scientific Research Project of Henan Province High Education Institutions/ ; }, mesh = {*Biofilms/drug effects ; *Helicobacter pylori/drug effects ; *Helicobacter Infections/drug therapy/therapy ; Animals ; *Anti-Bacterial Agents/pharmacology/chemistry ; *Mucus/metabolism ; Mice ; Free Radicals/chemistry ; Nanoparticles/chemistry ; Ultrasonic Waves ; }, abstract = {Helicobacter pylori (H. pylori) infection is closely associated with the development of various gastric diseases. The effectiveness of current clinical antibiotic therapy is hampered by the rise of drug-resistant strains and the formation of H. pylori biofilm. This paper reports a sonodynamic nanocomposite PtCu3-PDA@AIPH@Fucoidan (PPAF), which consists of dopamine-modified inorganic sonosensitizers PtCu3, alkyl radicals (R•) generator AIPH and fucoidan, can penetrate the mucus layer, target H. pylori, disrupt biofilms, and exhibit excellent bactericidal ability. In vitro experiments demonstrate that PPAF exhibits excellent acoustic kinetic properties, generating a significant amount of reactive oxygen species and oxygen-independent R• for sterilization under ultrasound stimulation. Simultaneously, the produced N2 can enhance the cavitation effect, aiding PPAF nanoparticles in penetrating the gastric mucus layer and disrupting biofilm integrity. This disruption allows more PPAF nanoparticles to bind to biofilm bacteria, facilitating the eradication of H. pylori. In vivo experiments demonstrate that ultrasound-stimulated PPAF exhibited significant antibacterial efficacy against H. pylori. Moreover, it effectively modulated the expression levels of inflammatory factors and maintained gastrointestinal microbiota stability when compared to the antibiotic treatment group. In summary, PPAF nanoparticles present a potential alternative to antibiotics, offering an effective and healthy option for treating H. pylori infection.}, }
@article {pmid38557720, year = {2024}, author = {Zulkarnaini, Z and Matsuura, N and Kanazawa, S and Honda, R and Yamamoto-Ikemoto, R}, title = {Optimizing start-up strategies for the two-inflow nitritation/anammox process: Influence on biofilm microbial community composition.}, journal = {Water science and technology : a journal of the International Association on Water Pollution Research}, volume = {89}, number = {6}, pages = {1583-1594}, pmid = {38557720}, issn = {0273-1223}, support = {JP18K19874//Japan Society for the Promotion of Science (JSPS) KAKENHI/ ; //Ministry of Higher Education and Research and Technology Indonesia/ ; }, mesh = {Wastewater ; Anaerobic Ammonia Oxidation ; Oxidation-Reduction ; Bioreactors/microbiology ; *Ammonium Compounds ; Bacteria ; *Microbiota ; Biofilms ; Nitrogen ; Sewage ; Denitrification ; }, abstract = {Low-energy nitrogen removal from ammonium-rich wastewater is crucial in preserving the water environment. A one-stage nitritation/anammox process with two inflows treating ammonium-containing wastewater, supplied from inside and outside the wound filter, is expected to stably remove nitrogen. Laboratory-scale reactors were operated using different start-up strategies; the first involved adding nitritation inoculum after anammox biomass formation in the filter, which presented a relatively low nitrogen removal rate (0.171 kg N/m[3] · d), at a nitrogen loading rate of 1.0 kg N/m[3] · d. Conversely, the second involved the gradual cultivation of anammox and nitritation microorganisms, which increased the nitrogen removal rate (0.276 kg N/m[3] · d). Furthermore, anammox (Candidatus Brocadia) and nitritation bacteria (Nitrosomonadaceae) coexisted in the biofilm formed on the filter surface. The abundance of nitritation bacteria (10.5%) in the reactor biofilm using the second start-up strategy was higher than that using the first (3.7%). Thus, the two-inflow nitritation/anammox process effectively induced habitat segregation using a suitable start-up strategy.}, }
@article {pmid38557711, year = {2024}, author = {Walker, P and Nerenberg, R and Pizarro, G and Aybar, M and Pavissich, JP and González, B and Pastén, P}, title = {Nitrate increases the capacity of an aerobic moving-bed biofilm reactor (MBBR) for winery wastewater treatment.}, journal = {Water science and technology : a journal of the International Association on Water Pollution Research}, volume = {89}, number = {6}, pages = {1454-1465}, pmid = {38557711}, issn = {0273-1223}, support = {FONDECYT 1200984//Agencia Nacional de Investigaci&#xf3;n y Desarrollo/ ; PIA/BASAL FB0002//Agencia Nacional de Investigaci&#xf3;n y Desarrollo/ ; VINNOVA 05CTE01-10//Corporaci&#xf3;n de Fomento de la Producci&#xf3;n/ ; }, mesh = {*Waste Disposal, Fluid/methods ; Nitrates ; Biofilms ; Bioreactors ; Organic Chemicals ; *Water Purification/methods ; Nitrogen ; Urea ; Denitrification ; }, abstract = {We used bench-scale tests and mathematical modeling to explore chemical oxygen demand (COD) removal rates in a moving-bed biofilm reactor (MBBR) for winery wastewater treatment, using either urea or nitrate as a nitrogen source. With urea addition, the COD removal fluxes ranged from 34 to 45 gCOD/m[2]-d. However, when nitrate was added, fluxes increased up to 65 gCOD/m[2]-d, twice the amount reported for aerobic biofilms for winery wastewater treatment. A one-dimensional biofilm model, calibrated with data from respirometric tests, accurately captured the experimental results. Both experimental and modelling results suggest that nitrate significantly increased MBBR capacity by stimulating COD oxidation in the deeper, oxygen-limited regions of the biofilm. Our research suggests that the addition of nitrate, or other energetic and broadly used electron acceptors, may provide a cost-effective means of covering peak COD loads in biofilm processes for winery or another industrial wastewater treatment.}, }
@article {pmid38556224, year = {2024}, author = {Kumari, S and Das, S}, title = {Functional amyloid fibrils of biofilm-forming marine bacterium Pseudomonas aeruginosa PFL-P1 interact spontaneously with pyrene and augment the biodegradation.}, journal = {International journal of biological macromolecules}, volume = {266}, number = {Pt 1}, pages = {131266}, doi = {10.1016/j.ijbiomac.2024.131266}, pmid = {38556224}, issn = {1879-0003}, mesh = {*Pyrenes/metabolism ; *Biofilms/drug effects/growth &amp; development ; *Pseudomonas aeruginosa/metabolism/drug effects ; *Amyloid/metabolism/chemistry ; *Biodegradation, Environmental ; Bacterial Proteins/metabolism/chemistry ; Spectroscopy, Fourier Transform Infrared ; }, abstract = {Bacteria thrive in biofilms embedding in the three-dimensional extracellular polymeric substances (EPS). Functional Amyloid in Pseudomonas (Fap), a protein in EPS, efficiently sequesters polycyclic aromatic hydrocarbons (PAHs). Present study reports the characterization of Fap fibrils from Pseudomonas aeruginosa PFL-P1 and describes the interaction with pyrene to assess the impact on pyrene degradation. Overexpression of fap in E. coli BL21(DE3) cells significantly enhances biofilm formation (p < 0.0001) and amyloid production (p = 0.0002), particularly with pyrene. Defibrillated Fap analysis reveals FapC monomers and increased fibrillation with pyrene. Circular Dichroism (CD), Fourier Transform Infrared Spectroscopy (FTIR), and X-ray Diffraction (XRD) unveil characteristic amyloid peaks and structural changes in Fap fibrils upon pyrene exposure. 3D-EEM analysis identifies a protein-like fluorophore in Fap fibrils, exhibiting pyrene-induced fluorescence quenching. Binding constants range from 5.23 to 7.78 M[-1], with ΔG of -5.10 kJ mol[-1] at 298 K, indicating spontaneous and exothermic interaction driven by hydrophobic forces. Exogenous Fap fibrils substantially increased the biofilm growth and pyrene degradation by P. aeruginosa PFL-P1 from 46 % to 64 % within 7 days (p = 0.0236). GC-MS identifies diverse metabolites, implying phthalic acid pathway in pyrene degradation. This study deepens insights into structural dynamics of Fap fibrils when exposed to pyrene, offering potential application in environmental bioremediation.}, }
@article {pmid38555648, year = {2024}, author = {Pujarern, P and Klaophimai, A and Amornsettachai, P and Panyayong, W and Chuenjitkuntaworn, B and Rokaya, D and Suphangul, S}, title = {Efficacy of Biofilm Removal on the Dental Implant Surface by Sodium Bicarbonate and Erythritol Powder Airflow System.}, journal = {European journal of dentistry}, volume = {18}, number = {4}, pages = {1022-1029}, pmid = {38555648}, issn = {1305-7456}, abstract = {OBJECTIVE: Peri-implantitis is a common complication in implant therapy and it is one of the main contributing factors to implant failure. This can be prevented by regular maintenance with mechanical debridement. One of the recent mechanical debridement methods is air abrasion therapy using different abrasive powders. This study aimed to evaluate the two common abrasive powders of different sizes (sodium bicarbonate and erythritol) for their biofilm cleaning efficacy on dental implant surfaces.<br><br>MATERIALS AND METHODS: &#x2003;In an in vitro setting, a total of 33 implants were divided into three groups: Group 1 (n =11)&#x2009;=&#x2009;no treatment; group 2 (n&#x2009;=&#x2009;11)&#x2009;=&#x2009;air abrasion therapy treated group using a sodium bicarbonate powder (AIRFLOW Powder Classic Comfort, EMS Electro Medical Systems, Nyon, Switzerland); and group 3 (n&#x2009;=&#x2009;11)&#x2009;=&#x2009;air abrasion therapy treated group using an erythritol powder (AIRFLOW Powder Plus, EMS Electro Medical Systems, Nyon, Switzerland). The implants in each group were subjected to biofilm formation, and group 2 and group 3 were treated with air abrasion therapy of two different powders having different sizes with the same settings. The particle sizes were sodium bicarbonate (40&#x2009;&#xb5;m) and erythritol (14&#xb5;m). The surface characteristics of the dental implants in three groups were studied from a digital camera and under the scanning electron microscope at different magnifications. The comparison of biofilm-removal efficacy between the three groups was performed by using a one-way analysis of variance with post-hoc Dunnett's T3 test. A p-value less than 0.05 was chosen to indicate statistical significance.<br><br>RESULTS: &#x2003;There were no statistical differences (p&#x2009;>&#x2009;0.05) between the two powder-treated groups for the biofilm cleaning efficacy. However, both groups showed significantly better biofilm-cleaning efficacy than the control group (p&#x2009;<&#x2009;0.05).<br><br>CONCLUSION: &#x2003;This suggests that both powders are effective in removing biofilm from the implant surface under ideal conditions. However, there was no clear distinction between the cleaning potential of the two powders, as both performed in a similar manner.}, }
@article {pmid38555642, year = {2024}, author = {Kriswandini, IL and Budi, HS and Justitia, FM}, title = {Examination of the Structure and Formation Streptococcus mutans Biofilm Induced by Glucose, Lactose, Soy Protein, and Iron.}, journal = {European journal of dentistry}, volume = {18}, number = {3}, pages = {834-840}, pmid = {38555642}, issn = {1305-7456}, abstract = {OBJECTIVE: Streptococcus mutans, the main causative agent of caries, have the ability to form biofilms on the surface of teeth. The availability of nutrients such as glucose, lactose, soy protein, and iron can influence S. mutans in biofilm formation. All four sources of nutrients have been shown to increase the formation of S. mutans biofilms. The purpose of this study was to determine the structure and thickness of S. mutans biofilms induced by glucose, lactose, soy protein, and iron.<br><br>MATERIALS AND METHODS: &#x2003;This experimental laboratory study aimed to examine the formation of biofilm structures (chemical elements) and determine the thickness of S. mutans biofilms induced by glucose, lactose, soy protein, and iron. The structures (chemical elements) were examined using scanning electron microscopy-energy-dispersive X-ray (SEM-EDX) analysis. Confocal laser scanning microscopy (CLSM) was used to determine the thickness of S. mutans biofilms with an Olympus FV1000 microscope, and the findings were analyzed using Olympus Fluoview Ver. 4.2a software.<br><br>RESULTS: &#x2003;It was established that the results of SEM-EDX examination of the structure of S. mutans biofilms induced by glucose had oxygen (O) as the dominant chemical element (30.24 w%); lactose reported oxygen (O) as the dominant element (29.65 w%); soy protein had carbon (C) as the dominant element (34.31 w%); and iron showed oxygen (O) as the dominant element (32.51 w%). The thickness (measured by the CLSM examination) of biofilms induced by glucose, lactose, soy protein, and iron were 17,666, 12,666, 18,000, and 15,666&#x2009;nm, respectively.<br><br>CONCLUSION: &#x2003;The structure of S. mutans biofilms induced by glucose, lactose, and iron contain the following elements in amounts from the highest to lowest: O, C, N, P, and S; the biofilm produced by S. mutans induced by soy protein in amounts from the highest to lowest comprised the elements: C, O, N, S, and P. The S. mutans biofilms induced by soy protein had the maximum thickness, followed by those induced by glucose, iron, and lactose.}, }
@article {pmid38552829, year = {2024}, author = {Zhao, ZC and Fan, SQ and Lu, Y and Tan, X and Liu, LY and Wang, XW and Liu, BF and Xing, DF and Ren, NQ and Xie, GJ}, title = {Deep insights into the biofilm formation mechanism and nitrogen-transformation network in a nitrate-dependent anaerobic methane oxidation biofilm.}, journal = {Environmental research}, volume = {252}, number = {Pt 1}, pages = {118810}, doi = {10.1016/j.envres.2024.118810}, pmid = {38552829}, issn = {1096-0953}, mesh = {*Biofilms/growth &amp; development ; *Methane/metabolism ; Anaerobiosis ; *Oxidation-Reduction ; *Nitrates/metabolism ; *Bioreactors/microbiology ; Nitrogen/metabolism ; Archaea/metabolism/genetics/physiology ; Bacteria/metabolism/genetics ; Waste Disposal, Fluid/methods ; }, abstract = {Nitrate/nitrite-dependent anaerobic methane oxidation (n-DAMO) process offers a promising solution for simultaneously achieving methane emissions reduction and efficient nitrogen removal in wastewater treatment. Although nitrogen removal at a practical rate has been achieved by n-DAMO biofilm process, the mechanisms of biofilm formation and nitrogen transformation remain to be elucidated. In this study, n-DAMO biofilms were successfully developed in the membrane aerated moving bed biofilm reactor (MAMBBR) and removed nitrate at a rate of 159 mg NO3[-]-N L[-1] d[-1]. The obvious increase in the content of extracellular polymeric substances (EPS) indicated that EPS production was important for biofilm development. n-DAMO microorganisms dominated the microbial community, and n-DAMO bacteria were the most abundant microorganisms. However, the expression of biosynthesis genes for proteins and polysaccharides encoded by n-DAMO archaea was significantly more active compared to other microorganisms, suggesting the central role of n-DAMO archaea in EPS production and biofilm formation. In addition to nitrate reduction, n-DAMO archaea were revealed to actively express dissimilatory nitrate reduction to ammonium and nitrogen fixation. The produced ammonium was putatively converted to dinitrogen gas through the joint function of n-DAMO archaea and n-DAMO bacteria. This study revealed the biofilm formation mechanism and nitrogen-transformation network in n-DAMO biofilm systems, shedding new light on promoting the application of n-DAMO process.}, }
@article {pmid38552580, year = {2024}, author = {He, Z and Li, Y and Yang, L and Li, Y and Cao, D and Wang, S and Xie, J and Yan, X}, title = {Sunlight-triggered prebiotic nanomotors for inhibition and elimination of pathogen and biofilm in aquatic environment.}, journal = {Journal of colloid and interface science}, volume = {665}, number = {}, pages = {634-642}, doi = {10.1016/j.jcis.2024.03.163}, pmid = {38552580}, issn = {1095-7103}, mesh = {Humans ; *Disinfectants/pharmacology ; Disinfection ; Sunlight ; Biofilms ; Anti-Bacterial Agents/pharmacology ; }, abstract = {Pathogen contamination in drinking water sources causes waterborne infectious diseases, seriously threatening human health. Nowadays, stimuli-responsive self-propelled nanomotors are appealing therapeutic agents for antibacterial therapy in vivo. However, achieving water disinfection using these nanobots is still a great challenge. Herein, we report on prebiotic galactooligosaccharide-based nanomotors for sunlight-regulated water disinfection. The nanomotors can utilize galactooligosaccharide-based N-nitrosamines as sunlight-responsive fuels for the spontaneous production of antibacterial nitric oxide. Such a solar-to-chemical energy conversion would power the nanomotors for self-diffusiophoresis, which could promote the diffusion of the nanomotors in water and their penetration in the biofilm, significantly enhancing the inhibition and elimination of the pathogens and their biofilms in aquatic environments. After water treatments, the prebiotic-based residual disinfectants can be selectively utilized by beneficial bacteria to effectively relieve safety risks to the environment and human health. The low-energy-cost, green and potent antibacterial nanobots show promising potential in water disinfection.}, }
@article {pmid38552483, year = {2024}, author = {Lu, Y and Liu, T and Hu, S and Yuan, Z and Dwyer, J and Akker, BVD and Lloyd, J and Guo, J}, title = {Coupling Partial Nitritation, Anammox and n-DAMO in a membrane aerated biofilm reactor for simultaneous dissolved methane and nitrogen removal.}, journal = {Water research}, volume = {255}, number = {}, pages = {121511}, doi = {10.1016/j.watres.2024.121511}, pmid = {38552483}, issn = {1879-2448}, abstract = {Anaerobic technologies with downstream autotrophic nitrogen removal have been proposed to enhance bioenergy recovery and transform a wastewater treatment plant from an energy consumer to an energy exporter. However, approximately 20-50 % of the produced methane is dissolved in the anaerobically treated effluent and is easily stripped into the atmosphere in the downstream aerobic process, contributing to the release of greenhouse gas emissions. This study aims to develop a solution to beneficially utilize dissolved methane to support high-level nitrogen removal from anaerobically treated mainstream wastewater. A novel technology, integrating Partial Nitritation, Anammox and Methane-dependent nitrite/nitrate reduction (i.e. PNAM) was demonstrated in a membrane-aerated biofilm reactor (MABR). With the feeding of ∼50 mg NH4[+]-N/L and ∼20 mg/L dissolved methane at a hydraulic retention time of 15 h, around 90 % of nitrogen and ∼100 % of dissolved methane can be removed together in the MABR. Microbial community characterization revealed that ammonia-oxidizing bacteria (AOB), nitrite-oxidizing bacteria (NOB), anammox bacteria, nitrite/nitrate-dependent anaerobic methane oxidation microorganisms (n-DAMO bacteria and archaea) and aerobic methanotrophs co-existed in the established biofilm. Batch tests confirmed the active microbial pathways and showed that AOB, anammox bacteria and n-DAMO microbes were jointly responsible for the nitrogen removal, and dissolved methane was mainly removed by the n-DAMO process, with aerobic methane oxidation making a minor contribution. In addition, the established system was robust against dynamic changes in influent composition. The study provides a promising technology for the simultaneous removal of dissolved methane and nitrogen from domestic wastewater, which can support the transformation of wastewater treatment from an energy- and carbon-intensive process, to one that is energy- and carbon-neutral.}, }
@article {pmid38551364, year = {2024}, author = {Zhao, E and Xiong, X and Li, X and Hu, H and Wu, C}, title = {Effect of Biofilm Forming on the Migration of Di(2-ethylhexyl)phthalate from PVC Plastics.}, journal = {Environmental science &amp; technology}, volume = {58}, number = {14}, pages = {6326-6334}, doi = {10.1021/acs.est.3c09021}, pmid = {38551364}, issn = {1520-5851}, mesh = {*Diethylhexyl Phthalate/metabolism ; Plasticizers ; Biofilms ; Environmental Pollution ; Water ; Plastics ; }, abstract = {Plastic additives, represented by plasticizers, are important components of plastic pollution. Biofilms inevitably form on plastic surfaces when plastic enters the aqueous environment. However, little is known about the effect of biofilms on plastic surfaces on the release of additives therein. In this study, PVC plastics with different levels of di(2-ethylhexyl)phthalate (DEHP) content were investigated to study the effect of biofilm growth on DEHP release. The presence of biofilms promoted the migration of DEHP from PVC plastics to the external environment. Relative to biofilm-free controls, although the presence of surface biofilm resulted in 0.8 to 11.6 times lower DEHP concentrations in water, the concentrations of the degradation product, monoethylhexyl phthalate (MEHP) in water, were 2.3 to 57.3 times higher. When the total release amounts of DEHP in the biofilm and in the water were combined, they were increased by 0.6-73 times after biofilm growth. However, most of the released DEHP was adsorbed in the biofilms and was subsequently degraded. The results of this study suggest that the biofilm as a new interface between plastics and the surrounding environment can affect the transport and transformation of plastic additives in the environment through barrier, adsorption, and degradation. Future research endeavors should aim to explore the transport dynamics and fate of plastic additives under various biofilm compositions as well as evaluate the ecological risks associated with their enrichment by biofilms.}, }
@article {pmid38549371, year = {2024}, author = {Zhu, R and Stone, T and Wang, Y}, title = {The role of shear rates on amyloid formation from biofilm peptide phenol-soluble modulins.}, journal = {Biophysical journal}, volume = {123}, number = {9}, pages = {1106-1115}, pmid = {38549371}, issn = {1542-0086}, mesh = {*Amyloid/chemistry/metabolism ; *Biofilms/growth &amp; development ; *Staphylococcus aureus ; Bacterial Toxins/chemistry/metabolism ; Kinetics ; }, abstract = {Biofilms, microbial communities enclosed in the self-produced extracellular matrix, have a significant impact on human health, environment, and industry. The pathogen Staphylococcus aureus (S. aureus) is recognized as one of the most frequent causes of biofilm-related infections. Phenol-soluble modulins (PSMs) serve as a crucial component, fortifying S. aureus biofilm matrix through self-assembly into amyloid fibrils, which enhances S. aureus colonization and resistance to antibiotics. However, the role of shear rate, one of the critical physiological factors within blood vessels, on the formation of PSM amyloids remains poorly understood. In this work, using a combination of thioflavin T fluorescence kinetic studies, circular dichroism spectrometry, and electron microscopy, we demonstrated that shear rates ranging from 150 to 300 s[-1] accelerate fibrillation of PSMα1, α3, and α4 into amyloids, resulting in elongated amyloid structures. Furthermore, PSMα1, α3, and α4 predominantly self-assembled into amyloid fibers with a cross-α structure under shear conditions, deviating from the typical β-sheet configuration of PSM amyloids. These findings imply the role of shear rates within the bloodstream on enhancing PSM self-assembly that is associated with S. aureus biofilm formation.}, }
@article {pmid38547720, year = {2024}, author = {Tan, J and Zhang, Z and Zheng, D and Mu, Y and Cao, B and Yang, J and Han, L and Huang, X}, title = {Structure-activity relationship and biofilm formation-related gene targets of oleanolic acid-type saponins from Pulsatilla chinensis against Candida albicans.}, journal = {Bioorganic chemistry}, volume = {146}, number = {}, pages = {107311}, doi = {10.1016/j.bioorg.2024.107311}, pmid = {38547720}, issn = {1090-2120}, mesh = {Humans ; Antifungal Agents/pharmacology ; Biofilms ; Candida albicans ; *Oleanolic Acid ; *Pulsatilla ; *Saponins/pharmacology ; Structure-Activity Relationship ; Animals ; }, abstract = {In the course of our investigations of antifungal natural products, the structure-activity relationship and antifungal activities of oleanolic acid-type saponins (1-28) from Pulsatilla chinensis against human and plant pathogenic fungi were elucidated. The analysis of structure-activity relationship of oleanolic acid-type saponins showed that the free carboxyl at C-28 was essential for their antifungal activities; the free hydroxyl group at the C-23 site of oleanolic acid-type saponins played a crucial role in their antifungal activities; the oligosaccharide chain at C-3 oleanolic acid-type saponins showed significant effects on antifungal efficacy and a disaccharide or trisaccharide moiety at position C-3 displayed optimal antifungal activity. The typical saponin pulchinenoside B3 (16, PB3) displayed satisfactory antifungal activity against human and plant pathogenic fungi, especially, C. albicans with an MIC value of 12.5 μg/mL. Furthermore, PB3 could inhibit the biofilm formation of C. albicans through downregulating the expression of the integrated network of biofilm formation-associated transcription factors (Bcr1 Efg1, Ndt80, Brg1, Rob1 and Tec1) and adhesion-related target genes (HWP1, ALS1, and ALS3). Meanwhile, we found that PB3 could effectively destroy the mature biofilm of C. albicans by the oxidative damage and inducing mitochondria-mediated apoptosis in cells.}, }
@article {pmid38547415, year = {2024}, author = {Sequeira, SB and Myntti, MF and Lee, J and Mont, MA}, title = {An Overview of Research for the Application of a Novel Biofilm-Preventing Surgical Irrigation System for Total Joint Arthroplasty Procedures in Order to Reduce the Risk of Periprosthetic Infection.}, journal = {Surgical technology international}, volume = {44}, number = {}, pages = {320-325}, doi = {10.52198/24.STI.44.OS1780}, pmid = {38547415}, issn = {1090-3941}, mesh = {Humans ; *Prosthesis-Related Infections/prevention &amp; control ; *Therapeutic Irrigation/methods/statistics &amp; numerical data ; *Biofilms ; *Arthroplasty, Replacement/adverse effects/instrumentation ; }, abstract = {Periprosthetic joint infection (PJI) is a serious postoperative complication in joint arthroplasty procedures that carries substantial morbidity and mortality associated with it. Several strategies have been developed both in the preoperative, perioperative, and postoperative periods to both combat and prevent the development of this devastating complication. Intraoperative irrigation is an important modality used during arthroplasty procedures prior to the implantation of final components that seeks to eradicate any biofilm formation. In this updated review, we discuss the XPERIENCE™ Advanced Surgical Irrigation solution (Next Science, Jacksonville, Florida) and the various completed, ongoing, and planned basic science and clinical investigations associated with it. Although there is already an impressive body of literature supporting its widespread utilization, future basic and clinical trials will continue to be performed to comprehensively characterize the effect this antimicrobial solution has on eliminating the risk of PJI following arthroplasty procedures.}, }
@article {pmid38545796, year = {2024}, author = {Matoso, FB and Montagner, F and Grecca, FS and Rampelotto, PH and Kopper, PMP}, title = {Microbial composition and diversity in intraradicular biofilm formed in situ: New concepts based on next-generation sequencing.}, journal = {Molecular oral microbiology}, volume = {39}, number = {5}, pages = {393-406}, doi = {10.1111/omi.12463}, pmid = {38545796}, issn = {2041-1014}, mesh = {*Biofilms/growth &amp; development ; Humans ; *High-Throughput Nucleotide Sequencing ; *RNA, Ribosomal, 16S/genetics ; *Bacteria/classification/genetics ; *Microbiota ; *Dental Pulp Cavity/microbiology ; Adult ; DNA, Bacterial/analysis ; Male ; Molar/microbiology ; Female ; Tooth Root/microbiology ; Young Adult ; }, abstract = {This study aimed to characterize the taxonomic composition of intraradicular multispecies biofilms (IMB) formed in situ in a model to reproduce clinical conditions. Twelve palatal roots of maxillary molars had its canals prepared. Two roots were randomly selected to sterility control. Ten intraoral prosthetic appliances with lateral slots were fabricated. The roots were positioned in the slots with the canal access open to the oral cavity. Eight volunteers wore the appliance for 21 days, and two wore it at two different time points. One root from each appliance was removed and stored at -20°C until DNA extraction and sequencing (n = 10). Biofilm was analyzed using next-generation sequencing and bioinformatics. The V4 hyper-variable region of the 16SrRNA gene was amplified and sequenced. For data analyses, the mothur pipeline was used for 16SrRNA processing, and subsequent analyses of the sequence dataset were performed in R using the Microbiome Analyst R package. The taxonomy-based analysis of bacterial communities identified 562 operational taxonomic units (OTUs), which belonged to 93 genera, 44 families, and 8 phyla. Bacterial colonization was different for each biofilm, and samples did not have the same group of bacteria. Alpha and beta diversity analysis revealed some general patterns of sample clustering. A core microbiome of prevalent OTUs and genera was identified. IMBs were heterogeneous when analyzed individually, but some diversity patterns were found after sample clustering. The experimental model seemed to reproduce the actual biofilm composition in endodontic infections, which suggests that it may be used to evaluate disinfection protocols.}, }
@article {pmid38544898, year = {2024}, author = {Işlek Köklü, Z and Akkuş Süt, P and Eskihoran Üçüncüoğlu, E and Kalayci, S and Şahin, F}, title = {Detection and characterization of the Pichia manshurica biofilm on the traditionally produced homemade apple vinegar.}, journal = {Turkish journal of chemistry}, volume = {48}, number = {1}, pages = {76-84}, pmid = {38544898}, issn = {1300-0527}, abstract = {Pichia yeasts are capable of forming biofilms during vinegar production and causing spoilage in various beverages. In addition, there exists a significant likelihood of encountering yeast contamination which can prevent vinegar production. The present study investigates the detection and characterization of the Pichia manshurica (P. manshurica) biofilm on traditionally produced homemade apple vinegar. The unique characteristics of vinegar were analyzed with a focus on the constituent, known as the "mother of vinegar", whose composition is comprised of cellulosic biofilm and acetic acid bacteria, including Gluconobacter oxydans (G. oxydans) Briefly, P. manshurica was isolated from apple vinegar and characterized in terms of the effect of biofilm formation on the surface of the cellulosic film on vinegar production. Microbial identification of vinegar with/without contamination by P. manshurica was analyzed through MALDI-TOF mass spectrometry (MS), and biofilm was characterized by Fourier transform infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM), and crystal violet staining. Accordingly, MS spectrum of isolates was identified as G. oxydans and P. manshurica with a ratio of 2.01 and 1.94, respectively. The FTIR analysis indicated that the peaks within the range of 1150-900 cm[-1] revealed a high content of polysaccharide in P. manchuria-contaminated biofilm, which is attributed to the stretching vibration of C-C and C-O bonds. The spectral region from 2921.51 to 2853.71 cm[-1] exhibited the characteristic of lipids in bacterial cell walls and membranes. SEM images of bacterial biofilms revealed a three-dimensional network composed of ultrafine fibers with a ribbon-like shape; however, the condensed reticulated structure was observed in contaminated biofilms. The presence of two microbial populations was detected regarding the morphological analysis. Crystal violet staining of contaminated-cellulosic biofilms visualized bacterial and yeast colonization. Concisely, this study emphasizes that the proliferation of Pichia during apple fermentation has the potential to adversely affect the quality of the homemade vinegar, due to its distinct biofilm characteristics.}, }
@article {pmid38544741, year = {2024}, author = {David, A and Louis, M and Tahrioui, A and Rodrigues, S and Labbé, C and Maillot, O and Barreau, M and Lesouhaitier, O and Cornelis, P and Chevalier, S and Bouffartigues, E}, title = {cmpX overexpression in Pseudomonas aeruginosa affects biofilm formation and cell morphology in response to shear stress.}, journal = {Biofilm}, volume = {7}, number = {}, pages = {100191}, pmid = {38544741}, issn = {2590-2075}, abstract = {UNLABELLED: Pseudomonas aeruginosa is an opportunistic pathogen causing chronic infections that are related to its ability to form biofilms. Mechanosensitive ion channels (Mcs) are cytoplasmic membrane proteins whose opening depends on a mechanical stress impacting the lipid bilayer. CmpX is a homologue of the small conductance MscS of Escherichia coli. The cmpX gene is part of a transcriptional cfrX-cmpX unit that is under the control of the cell envelope stress response ECF sigma factor SigX. CmpX was shown to regulate the activity of the hybrid sensor kinase PA1611 involved in the regulation of transition from a planktonic to a biofilm lifestyle. The deletion of cmpX leads to increased biofilm formation under static conditions. Herein, the effect of cmpX overexpression was investigated by confocal laser scanning microscopy in terms of biofilm formation and architecture, and matrix components production, in dynamic conditions. We show that overexpression of cmpX in P. aeruginosa leads to enhanced and altered biofilm architecture that seems to be associated to increased matrix components and the emergence of filamentous cells. These phenotypic alterations might occur potentially through a shear stress induced by the medium flow rate.<br><br>IMPORTANCE: CmpX is involved in biofilm formation and cell filamentation with regards to the medium flow.}, }
@article {pmid38544331, year = {2024}, author = {Wang, C and Defoirdt, T and Rajkovic, A}, title = {The impact of indole and mucin on sporulation, biofilm formation, and enterotoxin production in foodborne Clostridium perfringens.}, journal = {Journal of applied microbiology}, volume = {135}, number = {4}, pages = {}, doi = {10.1093/jambio/lxae083}, pmid = {38544331}, issn = {1365-2672}, support = {201808630020//China Scholarship Council/ ; BOF20/BAS/120//Ghent University/ ; 1506419N//Research Foundation Flanders/ ; }, mesh = {*Clostridium perfringens/genetics ; *Enterotoxins/genetics ; Mucins/metabolism ; Spores, Bacterial ; Biofilms ; }, abstract = {AIMS: Indole and mucin are compounds found in the host environment as they are produced by the host or by the host-associated microbiota. This study investigated whether indole and mucin impact Clostridium perfringens growth and sporulation, as well as enterotoxin production and biofilm formation.<br><br>METHODS AND RESULTS: There was no impact on growth of Cl. perfringens for up to 400&#xa0;&#xb5;M indole and 240&#xa0;mg/l mucin, and neither indole nor mucin affected sporulation. Reverse-transcriptase qPCR showed that mucin strongly upregulated the expression of Cl. perfringens enterotoxin (up to 121-fold increase), whereas indole had a much more modest effect (2-fold). This was also reflected in increased Cl. perfringens enterotoxin levels in mucin-treated Cl. perfringens (as assessed by a reversed passive latex agglutination assay). Finally, mucin and indole significantly increased biofilm formation of Cl. perfringens, although the effect size was relatively small (less than 1.5 fold).<br><br>CONCLUSION: These results indicate that Cl. perfringens can sense its presence in a host environment by responding to mucin, and thereby markedly increased enterotoxin production.}, }
@article {pmid38543751, year = {2024}, author = {Golosova, NN and Matveev, AL and Tikunova, NV and Khlusevich, YA and Kozlova, YN and Morozova, VV and Babkin, IV and Ushakova, TA and Zhirakovskaya, EV and Panina, EA and Ryabchikova, EI and Tikunov, AY}, title = {Bacteriophage vB_SepP_134 and Endolysin LysSte_134_1 as Potential Staphylococcus-Biofilm-Removing Biological Agents.}, journal = {Viruses}, volume = {16}, number = {3}, pages = {}, pmid = {38543751}, issn = {1999-4915}, support = {122022100238-7//the Russian state-funded project for ICBFM SB RAS/ ; }, mesh = {Humans ; Staphylococcus aureus ; *Bacteriophages/genetics ; Staphylococcus ; Staphylococcus epidermidis ; *Staphylococcal Infections/microbiology ; Anti-Bacterial Agents/pharmacology/therapeutic use ; Biofilms ; *Endopeptidases ; }, abstract = {Bacteria of the genus Staphylococcus are significant challenge for medicine, as many species are resistant to multiple antibiotics and some are even to all of the antibiotics we use. One of the approaches to developing new therapeutics to treat staphylococcal infections is the use of bacteriophages specific to these bacteria or the lytic enzymes of such bacteriophages, which are capable of hydrolyzing the cell walls of these bacteria. In this study, a new bacteriophage vB_SepP_134 (St 134) specific to Staphylococcus epidermidis was described. This podophage, with a genome of 18,275 bp, belongs to the Andhravirus genus. St 134 was able to infect various strains of 12 of the 21 tested coagulase-negative Staphylococcus species and one clinical strain from the Staphylococcus aureus complex. The genes encoding endolysin (LysSte134_1) and tail tip lysin (LysSte134_2) were identified in the St 134 genome. Both enzymes were cloned and produced in Escherichia coli cells. The endolysin LysSte134_1 demonstrated catalytic activity against peptidoglycans isolated from S. aureus, S. epidermidis, Staphylococcus haemolyticus, and Staphylococcus warneri. LysSte134_1 was active against S. aureus and S. epidermidis planktonic cells and destroyed the biofilms formed by clinical strains of S. aureus and S. epidermidis.}, }
@article {pmid38543484, year = {2024}, author = {Rosa-Masegosa, A and Rodriguez-Sanchez, A and Gorrasi, S and Fenice, M and Gonzalez-Martinez, A and Gonzalez-Lopez, J and Muñoz-Palazon, B}, title = {Microbial Ecology of Granular Biofilm Technologies for Wastewater Treatment: A Review.}, journal = {Microorganisms}, volume = {12}, number = {3}, pages = {}, pmid = {38543484}, issn = {2076-2607}, abstract = {Nowadays, the discharge of wastewater is a global concern due to the damage caused to human and environmental health. Wastewater treatment has progressed to provide environmentally and economically sustainable technologies. The biological treatment of wastewater is one of the fundamental bases of this field, and the employment of new technologies based on granular biofilm systems is demonstrating success in tackling the environmental issues derived from the discharge of wastewater. The granular-conforming microorganisms must be evaluated as functional entities because their activities and functions for removing pollutants are interconnected with the surrounding microbiota. The deep knowledge of microbial communities allows for the improvement in system operation, as the proliferation of microorganisms in charge of metabolic roles could be modified by adjustments to operational conditions. This is why engineering must consider the intrinsic microbiological aspects of biological wastewater treatment systems to obtain the most effective performance. This review provides an extensive view of the microbial ecology of biological wastewater treatment technologies based on granular biofilms for mitigating water pollution.}, }
@article {pmid38543172, year = {2024}, author = {Qaralleh, H and Saghir, SAM and Al-Limoun, MO and Dmor, SM and Khleifat, K and Al-Ahmad, BEM and Al-Omari, L and Tabana, Y and Mothana, RA and Al-Yousef, HM and Alqahtani, AM}, title = {Effect of Matricaria aurea Essential Oils on Biofilm Development, Virulence Factors and Quorum Sensing-Dependent Genes of Pseudomonas aeruginosa.}, journal = {Pharmaceuticals (Basel, Switzerland)}, volume = {17}, number = {3}, pages = {}, pmid = {38543172}, issn = {1424-8247}, support = {RSP2024R119//The Researchers Supporting Program, King Saud University, Riyadh, Saudi Arabia/ ; }, abstract = {The emergence of drug-resistant microorganisms presents a substantial global public health threat. The increase in pathogens resistant to commonly prescribed antibiotics underscores the urgent requirement to explore alternative treatment strategies. This study adopts a novel approach by harnessing natural resources, specifically essential oils (EO), to combat bacterial pathogenicity. The primary aim of this research was to analyze the chemical composition of the aerial part of the Matricaria aurea (M. aureas) EO and evaluate its potential for inhibiting quorum sensing (QS) and disrupting biofilm formation in Pseudomonas aeruginosa (P. aeruginosa). The gas chromatography-mass spectrometry (GCMS) analysis unveiled that α-bisabolol oxide A constituted the predominant portion, comprising 64.8% of the total, with β-bisabolene at 6.3% and α-farnesene at 4.8% following closely behind. The antibiofilm efficacy was observed at concentrations of 0.3, 0.15, and 0.08 mg/mL, demonstrating negligible effects on cell viability. Furthermore, the EO from M. aurea effectively inhibited the formation of P. aeruginosa biofilms by diminishing aggregation, hydrophobicity, and swarming motility. Significantly, the EO treatment resulted in a conspicuous decrease in the production of pyocyanin, rhamnolipid, and extracellular polymeric substances (EPS), along with a reduction in the enzymatic activity of protease and chitinase. The EO effectively hindered QS by disrupting QS mechanisms, resulting in a marked decline in the secretion of N-Acyl homoserine lactone (AHL) molecules and the expression of phazA1 and aprA genes. This investigation offers compelling evidence supporting the potential of M. aurea EO as a promising therapeutic candidate for addressing infectious diseases induced by biofilm formation.}, }
@article {pmid38543106, year = {2024}, author = {Campos, LAA and Neto, AFS and Scavuzzi, AML and Lopes, ACS and Santos-Magalhães, NS and Cavalcanti, IMF}, title = {Ceftazidime/Tobramycin Co-Loaded Chitosan-Coated Zein Nanoparticles against Antibiotic-Resistant and Biofilm-Producing Pseudomonas aeruginosa and Klebsiella pneumoniae.}, journal = {Pharmaceuticals (Basel, Switzerland)}, volume = {17}, number = {3}, pages = {}, pmid = {38543106}, issn = {1424-8247}, support = {88887311907/2018-00//Coordena&#xe7;&#xe3;o de Aperfeicoamento de Pessoal de N&#xed;vel Superior/ ; 408785/2022.5//National Council for Scientific and Technological Development/ ; 050427/2023-21//Universidade Federal de Pernambuco/ ; }, abstract = {This study aimed to co-encapsulate ceftazidime and tobramycin in zein nanoparticles coated with chitosan and to characterize and evaluate the antibacterial and antibiofilm activity against antibiotic-resistant Pseudomonas aeruginosa and Klebsiella pneumoniae. Zein nanoparticles, synthesized using the nanoprecipitation method, were characterized by their particle size (Ø), polydispersity index (PDI), zeta potential (ζ), pH, and encapsulation efficiency (%EE). The chitosan coating provided stability, and physicochemical analyses revealed chemical interactions, efficient drug encapsulation, and thermal stability. The release kinetics demonstrated controlled release in simulated gastric and intestinal pH. The antibacterial activity, assessed by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), indicated effectiveness against both pathogens. Antibiofilm assays, conducted using the crystal violet method, demonstrated the inhibition and eradication of biofilms. The chitosan-coated zein nanoparticles with CAZ and/or TOB exhibited Ø (315-335 nm), PDI (<0.2), ζ (+40 to +50 mV), pH (5), and %EE (>55%). Notably, the co-encapsulation formulation (CAZ-TOB-ZNP-CH) showed enhanced antibacterial and antibiofilm activities compared to the individual formulations. These findings suggest that the developed nanoparticles present a promising alternative for treating respiratory and intestinal infections caused by antibiotic-resistant and biofilm-producing P. aeruginosa and K. pneumoniae.}, }
@article {pmid38542379, year = {2024}, author = {Houtak, G and Nepal, R and Bouras, G and Shaghayegh, G and Bennett, C and Finnie, J and Fenix, K and Psaltis, AJ and Wormald, PJ and Vreugde, S}, title = {Staphylococcus aureus Biofilm-Secreted Factors Cause Mucosal Damage, Mast Cell Infiltration, and Goblet Cell Hyperplasia in a Rat Rhinosinusitis Model.}, journal = {International journal of molecular sciences}, volume = {25}, number = {6}, pages = {}, pmid = {38542379}, issn = {1422-0067}, support = {APP1196832//National Health and Medical Research Council/ ; University of Adelaide International Scholarships//University of Adelaide/ ; Top-up scholarship//The Hospital Research Foundation Group/ ; senior fellowship//Passe &amp; Williams Foundation/ ; }, mesh = {Humans ; Rats ; Animals ; Goblet Cells/pathology ; Staphylococcus aureus ; *Rhinosinusitis ; *Rhinitis/pathology ; Hyperplasia/pathology ; Mast Cells/pathology ; *Sinusitis/pathology ; Biofilms ; Chronic Disease ; }, abstract = {Chronic rhinosinusitis (CRS) is an inflammatory condition of the sinonasal mucosa. Despite being a common health issue, the exact cause of CRS is yet to be understood. However, research suggests that Staphylococcus aureus, particularly in its biofilm form, is associated with the disease. This study aimed to investigate the impact of long-term exposure to secreted factors of Staphylococcus aureus biofilm (SABSFs), harvested from clinical isolates of non-CRS carrier and CRS patients, on the nasal mucosa in a rat model. Animals were randomised (n = 5/group) to receive daily intranasal instillations of 40 μL (200 μg/μL) SABSFs for 28 days or vehicle control. The sinonasal samples were analysed through histopathology and transcriptome profiling. The results showed that all three intervention groups displayed significant lymphocytic infiltration (p ≤ 0.05). However, only the SABSFs collected from the CRSwNP patient caused significant mucosal damage, mast cell infiltration, and goblet cell hyperplasia compared to the control. The transcriptomics results indicated that SABSFs significantly enriched multiple inflammatory pathways and showed distinct transcriptional expression differences between the control group and the SABSFs collected from CRS patients (p ≤ 0.05). Additionally, the SABSF challenges induced the expression of IgA and IgG but not IgE. This in vivo study indicates that long-term exposure to SABSFs leads to an inflammatory response in the nasal mucosa with increased severity for S. aureus isolated from a CRSwNP patient. Moreover, exposure to SABSFs does not induce local production of IgE.}, }
@article {pmid38542256, year = {2024}, author = {Bravo, E and Arce, M and Ribeiro-Vidal, H and Herrera, D and Sanz, M}, title = {The Impact of Candida albicans in the Development, Kinetics, Structure, and Cell Viability of Biofilms on Implant Surfaces-An In Vitro Study with a Validated Multispecies Biofilm Model.}, journal = {International journal of molecular sciences}, volume = {25}, number = {6}, pages = {}, pmid = {38542256}, issn = {1422-0067}, mesh = {*Candida albicans ; Cell Survival ; *Dental Implants ; Biofilms ; Porphyromonas gingivalis ; }, abstract = {This study aimed to evaluate the impact of Candida albicans on subgingival biofilm formation on dental implant surfaces. Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) were used to compare biofilm structure and microbial biomass in the presence and absence of the fungus after periods of 24, 48, and 72 h. Quantitative polymerase chain reaction (qPCR) was used to quantify the number of viable and total micro-organisms for each of the biofilm-forming strains. A general linear model was applied to compare CLSM and qPCR results between the control and test conditions. The biofilm developed with C. albicans at 72 h had a higher bacterial biomass and a significantly higher cell viability (p < 0.05). After both 48 and 72 h of incubation, in the presence of C. albicans, there was a significant increase in counts of Fusobacterium nucleatum and Porphyromonas gingivalis and in the cell viability of Streptococcus oralis, Aggregatibacter actinomycetemcomitans, F. nucleatum, and P. gingivalis. Using a dynamic in vitro multispecies biofilm model, C. albicans exacerbated the development of the biofilm grown on dental implant surfaces, significantly increasing the number and cell viability of periodontal bacteria.}, }
@article {pmid38541692, year = {2024}, author = {Fehlhofer, J and Ries, J and Nickel, FT and Rothhammer, V and Schwab, S and Kesting, M and Buchbender, M}, title = {Expression of Inflammatory Mediators in Biofilm Samples and Clinical Association in Multiple Sclerosis Patients in Remission-A Pilot Study.}, journal = {Life (Basel, Switzerland)}, volume = {14}, number = {3}, pages = {}, pmid = {38541692}, issn = {2075-1729}, abstract = {Multiple sclerosis (MS) is a chronic inflammatory autoimmune disease of unknown etiology that affects the central nervous system and can lead to neurological impairment. Our aim was to determine whether MS patients also show inflammatory changes in the oral cavity more frequently than healthy individuals. For this purpose, we examined plaque samples for various mediators and their correlation with clinical findings. A study group (MS) and a control group were examined and compared. The plaque samples were analyzed for the expression of interleukins (IL-2, -6, -10), matrix metalloproteinases (MMP-7, MMP-9), and a surface antigen CD90 by quantitative real-time PCR. The clinical parameters examined were the Mombelli plaque index; bleeding on probing (BOP) index; periodontal pocket depth; and decayed, missing, and filled tooth (DMFT) index. The expression of MMP9 was significantly (p = 0.035) higher in the control group. The expression of IL-2 was increased four-fold in the MS group; however, this difference was not statistically significant. The mean PD (p < 0.001) and BOP index (p = 0.029) values were increased in the study group. The clinical parameters of the BOP index and PD were significantly amplified in the MS patients. However, no causal relationship between the investigated inflammatory mediators and the clinical findings could be established in this case series.}, }
@article {pmid38541385, year = {2024}, author = {Frąckiewicz, W and Pruss, A and Królikowski, M and Szymlet, P and Sobolewska, E}, title = {Comparison of the Intensity of Biofilm Production by Oral Microflora and Its Adhesion on the Surface of Zirconia Produced in Additive and Subtractive Technology: An In Vitro Study.}, journal = {Materials (Basel, Switzerland)}, volume = {17}, number = {6}, pages = {}, pmid = {38541385}, issn = {1996-1944}, abstract = {BACKGROUND: This in vitro study set out to find out how well oral cavity-dwelling bacteria can form biofilms and adhere on the surfaces of zirconium oxide samples created by 3D printing and milling technologies.<br><br>METHODS: 5 strains of microorganisms were used for the study, and 40 zirconium oxide samples were prepared, which were divided into two groups (n = 20)-20 samples produced using removal technology comprised the control group, while 20 samples produced by 3D printing technology comprised the test group. The prepared samples were placed in culture media of bacteria and fungi that naturally occur in the oral cavity. Then, the intensity of biofilm build-up on the samples was determined using qualitative and quantitative methods. The results for both materials were compared with each other.<br><br>RESULTS: No variations in the degree of biofilm deposition on zirconium oxide samples were found for the microorganisms Streptococcus mutans, Pseudomonas aeruginosa, Enterococcus faecalis, and Staphylococcus aureus. For Candida albicans fungi, more intense biofilm deposition was observed on samples made using 3D printing technology, but these differences were not statistically significant.<br><br>CONCLUSION: The biofilm accumulation intensity of ceramics produced by additive technology is comparable to that of milled zirconium oxide, which supports the material's broader use in clinical practice from a microbiological perspective. This ceramic has demonstrated its ability to compete with zirconium oxide produced by milling techniques in in vitro experiments, but sadly, no in vivo tests have yet been found to determine how this material will function in a patient's oral cavity.}, }
@article {pmid38540741, year = {2024}, author = {Demjanenko, P and Zheng, S and Crane, JK}, title = {SOS-Inducing Drugs Trigger Nucleic Acid Release and Biofilm Formation in Gram-Negative Bacteria.}, journal = {Biomolecules}, volume = {14}, number = {3}, pages = {}, pmid = {38540741}, issn = {2218-273X}, support = {77548-20-1138250//Department of Internal Medicine, University at Buffalo/ ; }, mesh = {*Nucleic Acids ; SOS Response, Genetics ; Biofilms ; Gram-Negative Bacteria ; DNA ; }, abstract = {Our laboratory recently reported that induction of the SOS response, triggered by SOS-inducing drugs, was accompanied by a large release of DNA from enteric bacteria. The SOS response release had not previously been reported to include release of extracellular DNA from bacterial cells. We followed up on those observations in this current study and found that not just double-stranded DNA was being released, but also single-stranded DNA, RNA, and protein. SOS-inducing drugs also triggered formation of biofilm at the air-fluid interface on glass, and the biofilms contained DNA. We extended our study to test whether inhibitors of the SOS response would block DNA release and found that SOS inhibitors, including zinc salts, nitric oxide donors, and dequalinium, inhibited SOS-induced DNA release. The understanding that SOS-induced DNA release is associated with formation of biofilms increases our appreciation of the role of the SOS response in pathogenesis, as well as in emergence of new antibiotic resistance. Our findings with SOS inhibitors also suggest that regimens might be devised that could block the deleterious effects of the SOS response, at least temporarily, when this is desired.}, }
@article {pmid38539154, year = {2024}, author = {Ahmed, NA and Othman, AS}, title = {Green fabrication of ZnO nanoparticles via spirulina platensis and its efficiency against biofilm forming pathogens.}, journal = {Microbial cell factories}, volume = {23}, number = {1}, pages = {92}, pmid = {38539154}, issn = {1475-2859}, mesh = {Animals ; Chlorocebus aethiops ; *Zinc Oxide/pharmacology/chemistry ; Vero Cells ; *Nanoparticles/chemistry ; Anti-Bacterial Agents/pharmacology/chemistry ; Biofilms ; *Metal Nanoparticles/chemistry ; Microbial Sensitivity Tests ; Plant Extracts/pharmacology/chemistry ; *Spirulina ; }, abstract = {Excessive consumption of antibiotics is considered one of the top public health threats, this necessitates the development of new compounds that can hamper the spread of infections. A facile green technology for the biosynthesis of Zinc oxide nanoparticles (ZnO NPs) using the methanol extract of Spirulina platensis as a reducing and stabilizing agent has been developed. A bunch of spectroscopic and microscopic investigations confirmed the biogenic generation of nano-scaled ZnO with a mean size of 19.103 ± 5.66 nm. The prepared ZnO NPs were scrutinized for their antibacterial and antibiofilm potentiality, the inhibition zone diameters ranged from 12.57 ± 0.006 mm to 17.33 ± 0.006 mm (at 20 µg/mL) for a variety of Gram-positive and Gram-negative pathogens, also significant eradication of the biofilms formed by Staphylococcus aureus and Klebsiella pneumoniae by 96.7% and 94.8% respectively was detected. The free radical scavenging test showed a promising antioxidant capacity of the biogenic ZnO NPs (IC50=78.35 µg/mL). Furthermore, the anti-inflammatory role detected using the HRBCs-MSM technique revealed an efficient stabilization of red blood cells in a concentration-dependent manner. In addition, the biogenic ZnO NPs have significant anticoagulant and antitumor activities as well as minimal cytotoxicity against Vero cells. Thus, this study offered green ZnO NPs that can act as a secure substitute for synthetic antimicrobials and could be applied in numerous biomedical applications.}, }
@article {pmid38538312, year = {2024}, author = {Oba, K and Suenaga, T and Yasuda, S and Kuroiwa, M and Hori, T and Lackner, S and Terada, A}, title = {Quest for Nitrous Oxide-reducing Bacteria Present in an Anammox Biofilm Fed with Nitrous Oxide.}, journal = {Microbes and environments}, volume = {39}, number = {1}, pages = {}, pmid = {38538312}, issn = {1347-4405}, mesh = {*Nitrous Oxide/metabolism ; RNA, Ribosomal, 16S/genetics ; *Anaerobic Ammonia Oxidation ; Bacteria ; Biofilms ; Vitamin B 12/metabolism ; Denitrification ; }, abstract = {N2O-reducing bacteria have been examined and harnessed to develop technologies that reduce the emission of N2O, a greenhouse gas produced by biological nitrogen removal. Recent investigations using omics and physiological activity approaches have revealed the ecophysiologies of these bacteria during nitrogen removal. Nevertheless, their involvement in‍ ‍anammox processes remain unclear. Therefore, the present study investigated the identity, genetic potential, and activity‍ ‍of N2O reducers in an anammox reactor. We hypothesized that N2O is limiting for N2O-reducing bacteria‍ ‍and an‍ ‍exogeneous N2O supply enriches as-yet-uncultured N2O-reducing bacteria. We conducted a 1200-day incubation of N2O-reducing bacteria in an anammox consortium using gas-permeable membrane biofilm reactors (MBfRs), which efficiently supply N2O in a bubbleless form directly to a biofilm grown on a gas-permeable membrane. A [15]N tracer test indicated that the supply of N2O resulted in an enriched biomass with a higher N2O sink potential. Quantitative PCR and 16S rRNA amplicon sequencing revealed Clade II nosZ type-carrying N2O-reducing bacteria as protagonists of N2O sinks. Shotgun metagenomics showed the genetic potentials of the predominant Clade II nosZ-carrying bacteria, Anaerolineae and Ignavibacteria in MBfRs. Gemmatimonadota and non-anammox Planctomycetota increased their abundance in MBfRs despite their overall lower abundance. The implication of N2O as an inhibitory compound scavenging vitamin B12, which is essential for the synthesis of methionine, suggested its limited suppressive effect on the growth of B12-dependent bacteria, including N2O reducers. We identified Dehalococcoidia and Clostridia as predominant N2O sinks in an anammox consortium fed exogenous N2O because of the higher metabolic potential of vitamin B12-dependent biosynthesis.}, }
@article {pmid38538267, year = {2024}, author = {Choi, LR and Harrison, Z and Montgomery, EC and Bush, JR and Abuhussein, E and Bumgardner, JD and Fujiwara, T and Jennings, JA}, title = {Chitosan Membranes Stabilized with Varying Acyl Lengths Release Cis-2-Decenoic Acid and Bupivacaine at Controlled Rates and Inhibit Pathogenic Biofilm.}, journal = {Frontiers in bioscience (Landmark edition)}, volume = {29}, number = {3}, pages = {108}, doi = {10.31083/j.fbl2903108}, pmid = {38538267}, issn = {2768-6698}, support = {W81XWH-20-1-0430//Military Burn Research Program (MBRP)/ ; //University of Memphis/University of Tennessee Health Science Center Joint Program in Biomedical Engineering/ ; }, mesh = {Humans ; Staphylococcus aureus ; *Chitosan/pharmacology ; Bupivacaine/pharmacology ; *Staphylococcal Infections ; *Pseudomonas Infections ; Biofilms ; Anti-Bacterial Agents/pharmacology ; Microbial Sensitivity Tests ; *Fatty Acids, Monounsaturated ; }, abstract = {BACKGROUND: Adherence of complex bacterial biofilm communities to burned tissue creates a challenge for treatment, with infection causing 51% of burn victim deaths. This study evaluated the release of therapeutics from wound care biomaterials and their antimicrobial activity against pathogens Staphylococcus aureus, Acinetobacter baumannii, and Pseudomonas aeruginosa.<br><br>METHODS: Electrospun chitosan membranes (ESCMs) were fabricated and acylated with chain lengths ranging from 6-10 carbons then loaded with 0.15 mg of anti-biofilm agent, cis-2-decenoic acid (C2DA), and 0.5 mg of local anesthetic, bupivacaine.<br><br>RESULTS: Combinations of therapeutics released from modified ESCMs at a cumulative amount of 45-70% of bupivacaine and less than 20% of C2DA. Results from bacterial studies suggest that this combination reduced biofilm 10-fold for S. aureus, 2-fold for Acinetobacter baumannii, and 2-3-fold for Pseudomonas aeruginosa by 24 hours. Additionally, dual loaded groups reduced planktonic Staphylococcus aureus ~4-fold by 24 hours as well as Acinetobacter baumannii ~3-fold by 48 hours.<br><br>CONCLUSIONS: The combination of therapeutics used has a significant role in biofilm prevention for selected strains via direct contact or diffusion in aqueous solutions.}, }
@article {pmid38537762, year = {2024}, author = {Xiao, J and Su, L and Chen, X and Huang, S and Zhou, M and Chen, Z}, title = {Molecular characteristics and biofilm formation capacity of nontypeable Haemophilus influenza strains isolated from lower respiratory tract in children.}, journal = {Microbial pathogenesis}, volume = {190}, number = {}, pages = {106632}, doi = {10.1016/j.micpath.2024.106632}, pmid = {38537762}, issn = {1096-1208}, mesh = {*Biofilms/growth &amp; development ; Humans ; *Haemophilus Infections/microbiology ; *Haemophilus influenzae/physiology/isolation &amp; purification/genetics/drug effects/classification ; *Anti-Bacterial Agents/pharmacology ; Child, Preschool ; Female ; Male ; Child ; Infant ; Microbial Sensitivity Tests ; Respiratory Tract Infections/microbiology/virology ; Microscopy, Electron, Scanning ; Drug Resistance, Bacterial ; Respiratory System/microbiology/virology ; }, abstract = {With the widespread introduction of the Hib conjugate vaccine, Nontypeable Haemophilus influenzae (NTHi) has emerged as the predominant strain globally. NTHi presents a significant challenge as a causative agent of chronic clinical infections due to its high rates of drug resistance and biofilm formation. While current research on NTHi biofilms in children has primarily focused on upper respiratory diseases, investigations into lower respiratory sources remain limited. In this study, we collected 54 clinical strains of lower respiratory tract origin from children. Molecular information and drug resistance features were obtained through whole gene sequencing and the disk diffusion method, respectively. Additionally, an in vitro biofilm model was established. All clinical strains were identified as NTHi and demonstrated the ability to form biofilms in vitro. Based on scanning electron microscopy and crystal violet staining, the strains were categorized into weak and strong biofilm-forming groups. We explored the correlation between biofilm formation ability and drug resistance patterns, as well as clinical characteristics. Stronger biofilm formation was associated with a longer cough duration and a higher proportion of abnormal lung imaging findings. Frequent intake of β-lactam antibiotics might be associated with strong biofilm formation. While a complementary relationship between biofilm-forming capacity and drug resistance may exist, further comprehensive studies are warranted. This study confirms the in vitro biofilm formation of clinical NTHi strains and establishes correlations with clinical characteristics, offering valuable insights for combating NTHi infections.}, }
@article {pmid38537561, year = {2024}, author = {Li, C and Teng, F and Wu, F and Zhang, H and Zhang, C and Zhang, D}, title = {Enhanced cavitation dose and reactive oxygen species production in microbubble-mediated sonodynamic therapy for inhibition of Escherichia coli and biofilm.}, journal = {Ultrasonics sonochemistry}, volume = {105}, number = {}, pages = {106853}, pmid = {38537561}, issn = {1873-2828}, mesh = {*Escherichia coli/drug effects/physiology ; *Biofilms/drug effects ; *Reactive Oxygen Species/metabolism ; *Microbubbles ; *Hematoporphyrins/pharmacology/chemistry ; Ultrasonic Therapy ; Anti-Bacterial Agents/pharmacology/chemistry ; }, abstract = {Sonodynamic therapy (SDT) is an emerging antibacterial therapy. This work selected hematoporphyrin monomethyl ether (HMME) as the sonosensitizer, and studied the enhanced inhibition effect of Escherichia coli and biofilm by microbubble-mediated cavitation in SDT. Firstly, the influence of microbubble-mediated cavitation effect on different concentrations of HMME (10 µg/ml, 30 µg/ml, 50 µg/ml) was studied. Using 1,3-diphenylisobenzofuran (DPBF) as an indicator, the effect of microbubble-mediated cavitation on the production of reactive oxygen species (ROS) was studied by absorption spectroscopy. Secondly, using agar medium, laser confocal microscopy and scanning electron microscopy, the effect of microbubble-mediated cavitation on the activity and morphology of bacteria was studied. Finally, the inhibitory effect of cavitation combined with SDT on biofilm was evaluated by laser confocal microscopy. The research results indicate that: (1) Microbubble-mediated ultrasound cavitation can significantly increase cavitation intensity and production of ROS. (2) Microbubble-mediated acoustic cavitation can alter the morphological structure of bacteria. (3) It can significantly enhance the inhibition of SDT on the activity of Escherichia coli and its biofilm. Compared with the control group, the addition of microbubbles resulted in an increase in the number of dead bacteria by 61.7 %, 71.6 %, and 76.2 %, respectively. The fluorescence intensity of the biofilm decreased by 27.1 %, 80.3 %, and 98.2 %, respectively. On the basis of adding microbubbles to ensure antibacterial and biofilm inhibition effects, this work studied the influence of cavitation effect in SDT on bacterial structure, providing a foundation for further revealing the intrinsic mechanism of SDT.}, }
@article {pmid38537031, year = {2024}, author = {Gomes, ACG and Maciel, JG and Garcia, AAMN and Coelho, LAS and Rodrigues, GM and Porto, VC and Polyzois, G and Klein, MI and Soares, S and Urban, VM and Neppelenbroek, KH}, title = {Anti-biofilm effectiveness of protocols for cleaning complete dentures in hospitalized patients: a randomized controlled trial.}, journal = {Journal of applied oral science : revista FOB}, volume = {32}, number = {}, pages = {e20230381}, pmid = {38537031}, issn = {1678-7765}, mesh = {Humans ; Agar/pharmacology ; Biofilms ; *Chlorhexidine/pharmacology ; Denture Cleansers/pharmacology ; Denture, Complete/microbiology ; Dentures/microbiology ; Hypochlorous Acid/pharmacology ; *Sodium Hypochlorite/pharmacology ; }, abstract = {BACKGROUND: Denture biofilm acts as a potential reservoir for respiratory pathogens, considerably increasing the risk of lung infections, specifically aspiration pneumonia, mainly 48h after hospital admission. The establishment of a straightforward, affordable, and applicable hygiene protocol in a hospital environment for the effective control of denture biofilm can be particularly useful to prevent respiratory infections or reduce the course of established lung disease.<br><br>OBJECTIVES: To evaluate the anti-biofilm effectiveness of denture cleaning protocols in hospitalized patients.<br><br>METHODOLOGY: The maxillary complete dentures (MCDs) of 340 hospitalized participants were randomly cleaned once using one of the following 17 protocols (n=20): brushing with distilled water, toothpaste, or neutral liquid soap (controls); immersion in chemical solutions (1% sodium hypochlorite, alkaline peroxide, 0.12% or 2% chlorhexidine digluconate), or microwave irradiation (650 W for 3 min) combined or not with brushing. Before and after the application of the protocols, the biofilm of the intaglio surface of the MCDs was evaluated using two methods: denture biofilm coverage area (%) and microbiological quantitative cultures on blood agar and Sabouraud Dextrose Agar (CFU/mL). Data were subjected to the Wilcoxon and Kruskal-Wallis tests (&#x3b1;=0.05).<br><br>RESULTS: All 17 protocols significantly reduced the percentage area of denture biofilm and microbial and fungal load (P<0.05). The highest percentage reductions in the area of denture biofilm were observed for 1% hypochlorite solution with or without brushing and for 2% chlorhexidine solution and microwave irradiation only in association with brushing (P<0.05). The greatest reductions in microbial and fungal load were found for the groups that used solutions of 2% chlorhexidine and 1% hypochlorite and microwave irradiation, regardless of the association with brushing (P<0.05).<br><br>CONCLUSIONS: A single immersion for 10 min in 1% sodium hypochlorite, even in the absence of brushing, proved to be a straightforward, rapid, low-cost, and effective protocol for cleaning the dentures of hospitalized patients.}, }
@article {pmid38536433, year = {2024}, author = {Nag, M and Bhattacharya, D and Garai, S and Dutta, B and Ghosh, S and Ray, RR and Lahiri, D}, title = {Immobilised antimicrobial peptides in downregulation of biofilm.}, journal = {Naunyn-Schmiedeberg's archives of pharmacology}, volume = {397}, number = {8}, pages = {5559-5569}, pmid = {38536433}, issn = {1432-1912}, mesh = {*Biofilms/drug effects/growth &amp; development ; Humans ; *Antimicrobial Peptides/pharmacology ; Animals ; Anti-Bacterial Agents/pharmacology ; Down-Regulation/drug effects ; }, abstract = {Colonisation of sessile bacterial species on biotic and abiotic surfaces is responsible for the development of various infections in humans. At present, biofilm-associated chronic infections have been a prime concern among the healthcare practitioners since they are impermeable to drugs, resulting in the development of antibiotic resistance or multi-drug resistance. For a few decades, a lot of research activity has been performed in the development of alternative therapeutics to combat biofilm-associated chronic infections. The presence of extracellular polymeric substance (EPS) prevents the permeation of most of the drugs rendering drug failures. The use of small molecules has been necessary to penetrate easily through the EPS and act on the targeted cells. In present days, the use of antimicrobial peptides (AMPs) has gained immense importance as alternative therapeutics since they exhibit a novel class of antibiotics exhibiting a wide spectrum of activity and possess a low rate of development of resistance. In the last few decades, a large number of AMPs have been identified from varied groups of organisms as effector molecules for innate immune system acting as an important line of defence. In this review, we will discuss the use of AMPs as effective agents to combat various biofilm-associated chronic infections.}, }
@article {pmid38535596, year = {2024}, author = {Senyagin, A and Sachivkina, N and Das, M and Arsenyuk, A and Mannapova, R and Mannapov, A and Kubatbekov, T and Svistunov, D and Petrukhina, O and Zharov, A and Zhabo, N}, title = {The Influence of L-Lysine-Alpha-Oxidase on the Biofilm Formation of Opportunistic Microorganisms Associated with Inflammatory Diseases of the Urinary Tract.}, journal = {Pathogens (Basel, Switzerland)}, volume = {13}, number = {3}, pages = {}, pmid = {38535596}, issn = {2076-0817}, abstract = {Urinary tract infections occupy a special niche among diseases of infectious etiology. Many microorganisms associated with urinary tract infections, such as Klebsiella oxytoca, Enterococcus spp., Morganella morganii, Moraxella catarrhalis, Pseudomonas aeruginosa, Proteus mirabilis, Staphylococcus aureus, Staphylococcus spp., and Candida spp., can form biofilms. The aim of this research was to study the effect of the enzyme L-lysine-Alpha-oxidase (LO) produced by the fungus Trichoderma harzianum Rifai on the biofilm formation process of microorganisms associated with urinary tract infections. Homogeneous LO showed a more pronounced effect than the culture liquid concentrate (cCL). When adding samples at the beginning of incubation, the maximum inhibition was observed in relation to Enterococcus faecalis 5960-cCL 86%, LO 95%; Enterococcus avium 1669-cCL 85%, LO 94%; Enterococcus cloacae 6392-cCL 83%, LO-98%; and Pseudomonas aeruginosa 3057-cCL 70%, LO-82%. The minimum inhibition was found in Candida spp. Scanning electron microscopy was carried out, and numerous morphological and structural changes were observed in the cells after culturing the bacterial cultures in a medium supplemented with homogeneous LO. For example, abnormal division was detected, manifesting as the appearance of joints in places where the bacteria diverge. Based on the results of this work, we can draw conclusions about the possibility of inhibiting microbial biofilm formation with the use of LO; especially significant inhibition was achieved when the enzyme was added at the beginning of incubation. Thus, LO can be a promising drug candidate for the treatment or prevention of infections associated with biofilm formation.}, }
@article {pmid38535555, year = {2024}, author = {González-Vázquez, R and Córdova-Espinoza, MG and Escamilla-Gutiérrez, A and Herrera-Cuevas, MDR and González-Vázquez, R and Esquivel-Campos, AL and López-Pelcastre, L and Torres-Cubillas, W and Mayorga-Reyes, L and Mendoza-Pérez, F and Gutiérrez-Nava, MA and Giono-Cerezo, S}, title = {Detection of mecA Genes in Hospital-Acquired MRSA and SOSA Strains Associated with Biofilm Formation.}, journal = {Pathogens (Basel, Switzerland)}, volume = {13}, number = {3}, pages = {}, pmid = {38535555}, issn = {2076-0817}, support = {SIP 20160618//Instituto Polit&#xe9;cnico Nacional/ ; }, abstract = {Methicillin-resistant (MR) Staphylococcus aureus (SA) and others, except for Staphylococcus aureus (SOSA), are common in healthcare-associated infections. SOSA encompass largely coagulase-negative staphylococci, including coagulase-positive staphylococcal species. Biofilm formation is encoded by the icaADBC operon and is involved in virulence. mecA encodes an additional penicillin-binding protein (PBP), PBP2a, that avoids the arrival of β-lactams at the target, found in the staphylococcal cassette chromosome mec (SCCmec). This work aims to detect mecA, the bap gene, the icaADBC operon, and types of SCCmec associated to biofilm in MRSA and SOSA strains. A total of 46% (37/80) of the strains were S. aureus, 44% (35/80) S. epidermidis, 5% (4/80) S. haemolyticus, 2.5% (2/80) S. hominis, 1.25% (1/80) S. intermedius, and 1.25% (1/80) S. saprophyticus. A total of 85% were MR, of which 95.5% showed mecA and 86.7% β-lactamase producers; thus, Staphylococcus may have more than one resistance mechanism. Healthcare-associated infection strains codified type I-III genes of SCCmec; types IV and V were associated to community-acquired strains (CA). Type II prevailed in MRSA mecA strains and type II and III in MRSOSA (methicillin-resistant staphylococci other than Staphylococcus aureus). The operon icaADBC was found in 24% of SA and 14% of SOSA; probably the arrangement of the operon, fork formation, and mutations influenced the variation. Methicillin resistance was mainly mediated by the mecA gene; however, there may be other mechanisms that also participate, since biofilm production is related to genes of the icaADBC operon and methicillin resistance was not associated with biofilm production. Therefore, it is necessary to strengthen surveillance to prevent the spread of these outbreaks both in the nosocomial environment and in the community.}, }
@article {pmid38535474, year = {2024}, author = {Carbone, D and Pecoraro, C and Scianò, F and Catania, V and Schillaci, D and Manachini, B and Cascioferro, S and Diana, P and Parrino, B}, title = {Novel [1,3,4]Thiadiazole[3,2-a]pyrimidin-5-ones as Promising Biofilm Dispersal Agents against Relevant Gram-Positive and Gram-Negative Pathogens.}, journal = {Marine drugs}, volume = {22}, number = {3}, pages = {}, pmid = {38535474}, issn = {1660-3397}, support = {ARS01_00934//European Union 2014-2020 PON Ricerca e Innovazione grant from the Italian Ministry of Education/ ; }, mesh = {*Thiadiazoles ; Biofilms ; Biological Assay ; Candida albicans ; Hybridization, Genetic ; }, abstract = {Biofilm-associated infections pose significant challenges in healthcare settings due to their resistance to conventional antimicrobial therapies. In the last decade, the marine environment has been a precious source of bioactive molecules, including numerous derivatives with antibiofilm activity. In this study, we reported the synthesis and the biological evaluation of a new series of twenty-two thiadiazopyrimidinone derivatives obtained by using a hybridization approach combining relevant chemical features of two important classes of marine compounds: nortopsentin analogues and Essramycin derivatives. The synthesized compounds were in vitro tested for their ability to inhibit biofilm formation and to disrupt mature biofilm in various bacterial strains. Among the tested compounds, derivative 8j exhibited remarkable dispersal activity against preformed biofilms of relevant Gram-positive and Gram-negative pathogens, as well as towards the fungus Candida albicans, showing BIC50 values ranging from 17 to 40 µg/mL. Furthermore, compound 8j was in vivo assayed for its toxicity and the anti-infective effect in a Galleria mellonella model. The results revealed a promising combination of anti-infective properties and a favorable toxicity profile for the treatment of severe chronic biofilm-mediated infections.}, }
@article {pmid38534698, year = {2024}, author = {Akir, A and Senhaji-Kacha, A and Muñoz-Egea, MC and Esteban, J and Aguilera-Correa, JJ}, title = {Biofilm Development by Mycobacterium avium Complex Clinical Isolates: Effect of Clarithromycin in Ultrastructure.}, journal = {Antibiotics (Basel, Switzerland)}, volume = {13}, number = {3}, pages = {}, pmid = {38534698}, issn = {2079-6382}, abstract = {BACKGROUND: The Mycobacterium avium complex includes the commonest non-tuberculous mycobacteria associated with human infections. These infections have been associated with the production of biofilms in many cases, but there are only a few studies about biofilms produced by the species included in this group.<br><br>METHODS: Three collection strains (M. avium ATCC25291, M. intracellulare ATCC13950, and M. chimaera DSM756), three clinically significant strains (647, 657, and 655), and three clinically non-significant ones (717, 505, and 575) of each species were included. The clinical significance of the clinical isolates was established according to the internationally accepted criteria. The biofilm ultrastructure was studied by Confocal-Laser Scanning Microscopy by using BacLight Live-Dead and Nile Red stains. The viability, covered surface, height, and relative autofluorescence were measured in several images/strain. The effect of clarithromycin was studied by using the technique described by Mu&#xf1;oz-Egea et al. with modifications regarding incubation time. The study included clarithromycin in the culture medium at a concentration achievable in the lungs (11.3 mg/L), using one row of wells as the control without antibiotics. The bacterial viability inside the biofilm is expressed as a percentage of viable cells. The differences between the different parameters of the biofilm ultrastructure were analyzed by using the Kruskal-Wallis test. The correlation between bacterial viability in the biofilm and treatment time was evaluated by using Spearman's rank correlation coefficient (&#x3c1;).<br><br>RESULTS: The strains showed differences between them with all the studied parameters, but neither a species-specific pattern nor a clinical-significance-specific pattern were detected. For the effect of clarithromycin, the viability of the bacteria contained in the biofilm was inversely proportional to the exposure time of the biofilm (&#x3c1; > -0.3; p-value < 0.05), excluding two M. chimaera strains (M. chimaera DSM756 and 575), which showed a weak positive correlation with treatment time (0.2 < &#x3c1; < 0.39; p-value < 0.05). Curiously, despite a clarithromycin treatment of 216 h, the percentage of the biofilm viability of the strains evaluated here was not less than 40% at best (M. avium 717).<br><br>CONCLUSIONS: All the M. avium complex strains studied can form biofilm in vitro, but the ultrastructural characteristics between them suggest that these are strain-specific characteristics unrelated to the species or the clinical significance. The clarithromycin effect on MAC species is biofilm-age/time-of-treatment-dependent and appears to be strain-specific while being independent of the clinical significance of the strain.}, }
@article {pmid38534200, year = {2024}, author = {Lopes, A-A and Vendrell-Fernández, S and Deschamps, J and Georgeault, S and Cokelaer, T and Briandet, R and Ghigo, J-M}, title = {Bile-induced biofilm formation in Bacteroides thetaiotaomicron requires magnesium efflux by an RND pump.}, journal = {mBio}, volume = {15}, number = {5}, pages = {e0348823}, pmid = {38534200}, issn = {2150-7511}, support = {ANR 20CE15002201, ANR-10-LABX-62-IBEID//Agence Nationale de la Recherche (ANR)/ ; DEQ20180339185//Fondation pour la Recherche M&#xe9;dicale (FRM)/ ; }, mesh = {*Biofilms/growth &amp; development ; *Bacteroides thetaiotaomicron/physiology/metabolism ; *Magnesium/metabolism ; *Bacterial Proteins/metabolism/genetics ; *Bile/metabolism ; Humans ; Membrane Transport Proteins/metabolism/genetics ; Gastrointestinal Microbiome/physiology ; Gene Expression Regulation, Bacterial ; }, abstract = {Bacteroides thetaiotaomicron is a prominent member of the human gut microbiota contributing to nutrient exchange, gut function, and maturation of the host's immune system. This obligate anaerobe symbiont can adopt a biofilm lifestyle, and it was recently shown that B. thetaiotaomicron biofilm formation is promoted by the presence of bile. This process also requires a B. thetaiotaomicron extracellular DNase, which is not, however, regulated by bile. Here, we showed that bile induces the expression of several Resistance-Nodulation-Division (RND) efflux pumps and that inhibiting their activity with a global competitive efflux inhibitor impaired bile-dependent biofilm formation. We then showed that, among the bile-induced RND-efflux pumps, only the tripartite BT3337-BT3338-BT3339 pump, re-named BipABC [for Bile Induced Pump A (BT3337), B (BT3338), and C (BT3339)], is required for biofilm formation. We demonstrated that BipABC is involved in the efflux of magnesium to the biofilm extracellular matrix, which leads to a decrease of extracellular DNA concentration. The release of magnesium in the biofilm matrix also impacts biofilm structure, potentially by modifying the electrostatic repulsion forces within the matrix, reducing interbacterial distance and allowing bacteria to interact more closely and form denser biofilms. Our study therefore, identified a new molecular determinant of B. thetaiotaomicron biofilm formation in response to bile salts and provides a better understanding on how an intestinal chemical cue regulates biofilm formation in a major gut symbiont.IMPORTANCEBacteroides thetaiotaomicron is a prominent member of the human gut microbiota able to degrade dietary and host polysaccharides, altogether contributing to nutrient exchange, gut function, and maturation of the host's immune system. This obligate anaerobe symbiont can adopt a biofilm community lifestyle, providing protection against environmental factors that might, in turn, protect the host from dysbiosis and dysbiosis-related diseases. It was recently shown that B. thetaiotaomicron exposure to intestinal bile promotes biofilm formation. Here, we reveal that a specific B. thetaiotaomicron membrane efflux pump is induced in response to bile, leading to the release of magnesium ions, potentially reducing electrostatic repulsion forces between components of the biofilm matrix. This leads to a reduction of interbacterial distance and strengthens the biofilm structure. Our study, therefore, provides a better understanding of how bile promotes biofilm formation in a major gut symbiont, potentially promoting microbiota resilience to stress and dysbiosis events.}, }
@article {pmid38534119, year = {2024}, author = {Gu, Y and Liu, Y and Mao, W and Peng, Y and Han, X and Jin, H and Xu, J and Chang, L and Hou, Y and Shen, X and Liu, X and Yang, Y}, title = {Functional versatility of Zur in metal homeostasis, motility, biofilm formation, and stress resistance in Yersinia pseudotuberculosis.}, journal = {Microbiology spectrum}, volume = {12}, number = {5}, pages = {e0375623}, pmid = {38534119}, issn = {2165-0497}, support = {2021YFA0909600//MOST | National Key Research and Development Program of China (NKPs)/ ; 31725003, 32330004//MOST | National Natural Science Foundation of China (NSFC)/ ; 32370048//MOST | National Natural Science Foundation of China (NSFC)/ ; 22JHZ008//Shaanxi Fundamental Science Research Project for Chemistry &amp; Biology/ ; QYLF-JSYY-2020029//the Comprehensive treatment of Xiaokongtong Gully Project: Research and application of in-situ greening and soil consolidation technology/ ; }, mesh = {*Yersinia pseudotuberculosis/genetics/metabolism/physiology ; *Biofilms/growth &amp; development ; *Homeostasis ; *Bacterial Proteins/genetics/metabolism ; *Gene Expression Regulation, Bacterial ; *Zinc/metabolism ; Stress, Physiological ; Metals/metabolism ; Virulence/genetics ; Repressor Proteins/genetics/metabolism ; }, abstract = {UNLABELLED: Zur (zinc uptake regulator) is a significant member of the Fur (ferric uptake regulator) superfamily, which is widely distributed in bacteria. Zur plays crucial roles in zinc homeostasis and influences cell development and environmental adaptation in various species. Yersinia pseudotuberculosis is a Gram-negative enteric that pathogen usually serves as a model organism in pathogenicity studies. The regulatory effects of Zur on the zinc transporter ZnuABC and the protein secretion system T6SS have been documented in Y. pseudotuberculosis. In this study, a comparative transcriptomics analysis between a ∆zur mutant and the wild-type (WT) strain of Y. pseudotuberculosis was conducted using RNA-seq. This analysis revealed global regulation by Zur across multiple functional categories, including membrane transport, cell motility, and molecular and energy metabolism. Additionally, Zur mediates the homeostasis not only of zinc but also ferric and magnesium in vivo. There was a notable decrease in 35 flagellar biosynthesis and assembly-related genes, leading to reduced swimming motility in the ∆zur mutant strain. Furthermore, Zur upregulated multiple simple sugar and oligopeptide transport system genes by directly binding to their promoters. The absence of Zur inhibited biofilm formation as well as reduced resistance to chloramphenicol and acidic stress. This study illustrates the comprehensive regulatory functions of Zur, emphasizing its importance in stress resistance and pathogenicity in Y. pseudotuberculosis.<br><br>IMPORTANCE: Bacteria encounter diverse stresses in the environment and possess essential regulators to modulate the expression of genes in responding to the stresses for better fitness and survival. Zur (zinc uptake regulator) plays a vital role in zinc homeostasis. Studies of Zur from multiple species reviewed that it influences cell development, stress resistance, and virulence of bacteria. Y. pseudotuberculosis is an enteric pathogen that serves a model organism in the study of pathogenicity, virulence factors, and mechanism of environmental adaptation. In this study, transcriptomics analysis of Zur's regulons was conducted in Y. pseudotuberculosis. The functions of Zur as a global regulator in metal homeostasis, motility, nutrient acquisition, glycan metabolism, and nucleotide metabolism, in turn, increasing the biofilm formation, stress resistance, and virulence were reviewed. The importance of Zur in environmental adaptation and pathogenicity of Y. pseudotuberculosis was emphasized.}, }
@article {pmid38533074, year = {2024}, author = {Wang, J and Hu, Y and Xie, Y}, title = {Hotspots and frontiers in Helicobacter pylori biofilm research: A bibliometric and visualization analysis from 1998 to 2023.}, journal = {Heliyon}, volume = {10}, number = {6}, pages = {e27884}, pmid = {38533074}, issn = {2405-8440}, abstract = {BACKGROUND: Helicobacterpylori (H. pylori) biofilm formation is a key factor in refractory H. pylori infection. The aim of this study was to understand research trends in H. pylori biofilms.<br><br>METHODS: The Web of Science Core Collection database was used to retrieve publications published from 1998 to 2023. Different kinds of software, EXCEL, an online bibliometric analysis platform, and the VOS viewer were used to evaluate and visualize the bibliometric data.<br><br>RESULTS: In total, 184 publications were identified, and the number of publications increased annually. The USA made the greatest contributions to this research field, while Helicobacter was the most productive journal. Grande rossella published the most papers, and the most productive institution was Gabriele D'Annunzio university. Co-occurrence network maps revealed that the keyword "Helicobacter pylori" ranked first in research field, and the keyword of "biofilm formation" and "in vitro" began to appear in the past three to five years. The majority of the five most-cited articles (60%) were published in USA and focused on the mechanism of H. pylori biofilm formation.<br><br>CONCLUSION: The annual number of publications on H. pylori biofilms has increased steadily over the past two decades and will continue to increase. Future studies should focus on evaluate the pharmacological effects, efficacy and safety of these anti-biofilm treatments in animal models and clinical trials.}, }
@article {pmid38532403, year = {2024}, author = {Dishan, A and Barel, M and Hizlisoy, S and Arslan, RS and Hizlisoy, H and Gundog, DA and Al, S and Gonulalan, Z}, title = {The ARIMA model approach for the biofilm-forming capacity prediction of Listeria monocytogenes recovered from carcasses.}, journal = {BMC veterinary research}, volume = {20}, number = {1}, pages = {123}, pmid = {38532403}, issn = {1746-6148}, mesh = {Animals ; Cattle ; *Listeria monocytogenes/genetics ; Biofilms ; Temperature ; Food Handling ; Models, Statistical ; }, abstract = {The present study aimed to predict the biofilm-formation ability of L. monocytogenes isolates obtained from cattle carcasses via the ARIMA model at different temperature parameters. The identification of L. monocytogenes obtained from carcass samples collected from slaughterhouses was determined by PCR. The biofilm-forming abilities of isolates were phenotypically determined by calculating the OD value and categorizing the ability via the microplate test. The presence of some virulence genes related to biofilm was revealed by QPCR to support the biofilm profile genotypically. Biofilm-formation of the isolates was evaluated at different temperature parameters (37 °C, 22 °C, 4 °C and - 20 °C). Estimated OD values were obtained with the ARIMA model by dividing them into eight different estimation groups. The prediction performance was determined by performance measurement metrics (ME, MAE, MSE, RMSE, MPE and MAPE). One week of incubation showed all isolates strongly formed biofilm at all controlled temperatures except - 20 °C. In terms of the metrics examined, the 3 days to 7 days forecast group has a reasonable prediction accuracy based on OD values occurring at 37 °C, 22 °C, and 4 °C. It was concluded that measurements at 22 °C had lower prediction accuracy compared to predictions from other temperatures. Overall, the best OD prediction accuracy belonged to the data obtained from biofilm formation at -20 °C. For all temperatures studied, especially after the 3 days to 7 days forecast group, there was a significant decrease in the error metrics and the forecast accuracy increased. When evaluating the best prediction group, the lowest RMSE at 37 °C (0.055), 22 °C (0.027) and 4 °C (0.024) belonged to the 15 days to 21 days group. For the OD predictions obtained at -20 °C, the 15 days to 21 days prediction group had also good performance (0.011) and the lowest RMSE belongs to the 7 days to 15 days group (0.007). In conclusion, this study will guide in using indicator parameters to evaluate biofilm forming ability to predict optimum temperature-time. The ARIMA models integrated with this study can be useful tools for industrial application and risk assessment studies using different parameters such as pH, NaCl concentration, and especially temperature applied during food processing and storage on the biofilm-formation ability of L. monocytogenes.}, }
@article {pmid38530134, year = {2024}, author = {Araújo, GDS and Brilhante, RSN and Rocha, MGD and Aguiar, L and Castelo-Branco, DSCM and Guedes, GMM and Sidrim, JJC and Pereira Neto, WA and Rocha, MFG}, title = {Anthraquinones against Cryptococcus neoformans sensu stricto: antifungal interaction, biofilm inhibition and pathogenicity in the Caenorhabditis elegans model.}, journal = {Journal of medical microbiology}, volume = {73}, number = {3}, pages = {}, doi = {10.1099/jmm.0.001815}, pmid = {38530134}, issn = {1473-5644}, mesh = {Animals ; *Cryptococcus neoformans ; Antifungal Agents/pharmacology ; Caenorhabditis elegans ; Itraconazole ; Virulence ; *Cryptococcosis ; Anthraquinones/pharmacology ; Biofilms ; *Anthracenes ; }, abstract = {Introduction. Cryptococcal biofilms have been associated with persistent infections and antifungal resistance. Therefore, strategies, such as the association of natural compounds and antifungal drugs, have been applied for the prevention of biofilm growth. Moreover, the Caenorhabditis elegans pathogenicity model has been used to investigate the capacity to inhibit the pathogenicity of Cryptococcus neoformans sensu stricto.Hypothesis. Anthraquinones and antifungals are associated with preventing C. neoformans sensu stricto biofilm formation and disrupting these communities. Antraquinones reduced the C. neoformans sensu stricto pathogenicity in the C. elegans model.Aim. This study aimed to evaluate the in vitro interaction between aloe emodin, barbaloin or chrysophanol and itraconazole or amphotericin B against growing and mature biofilms of C. neoformans sensu stricto.Methodology. Compounds and antifungal drugs were added during biofilm formation or after 72 h of growth. Then, the metabolic activity was evaluated by the MTT reduction assay, the biomass by crystal-violet staining and the biofilm morphology by confocal laser scanning microscopy. C. neoformans sensu stricto's pathogenicity was investigated using the nematode C. elegans. Finally, pathogenicity inhibition by aloe emodin, barbarloin and chrysophanol was investigated using this model.Results. Anthraquinone-antifungal combinations affected the development of biofilms with a reduction of over 60 % in metabolic activity and above 50 % in biomass. Aloe emodin and barbaloin increased the anti-biofilm activity of antifungal drugs. Chrysophanol potentiated the effect of itraconazole against C. neoformans sensu stricto biofilms. The C. elegans mortality rate reached 76.7 % after the worms were exposed to C. neoformans sensu stricto for 96 h. Aloe emodin, barbaloin and chrysophanol reduced the C. elegans pathogenicity with mortality rates of 61.12 %, 65 % and 53.34 %, respectively, after the worms were exposed for 96 h to C. neoformans sensu stricto and these compounds at same time.Conclusion. These results highlight the potential activity of anthraquinones to increase the effectiveness of antifungal drugs against cryptococcal biofilms.}, }
@article {pmid38529559, year = {2024}, author = {Hadjab, W and Zellagui, A and Mokrani, M and Öztürk, M and Ceylan, &#xd6; and Gherraf, N and Bensouici, C}, title = {Pharmacological Potential Effects of Algerian Propolis Against Oxidative Stress, Multidrug-Resistant Pathogens Biofilm and Quorum-Sensing.}, journal = {Turkish journal of pharmaceutical sciences}, volume = {21}, number = {1}, pages = {71-80}, pmid = {38529559}, issn = {2148-6247}, abstract = {OBJECTIVES: This study sought to examine the chemical profile, antioxidant, antimicrobial, antibiofilm, and anti-quorum sensing potential of two propolis ethanolic extracts (PEEs) collected from northeast Algeria.<br><br>MATERIALS AND METHODS: To achieve the main objectives of this study, multiple in vitro tests were employed. The phenolic and flavonoid contents were analyzed, and the chemical composition of both PEE was determined by high-performance liquid chromatography. The antioxidant properties of the propolis extracts were investigated using six complementary tests. The inhibitory effects of propolis extracts were evaluated against multidrug-resistant (MDR) clinical isolates using agar well diffusion and microdilution methods, whereas their antibiofilm and quorum-sensing disruption effects were determined by spectrophotometric microplate methods.<br><br>RESULTS: The results demonstrated that phenolic and flavonoid contents were higher in propolis from the Guelma (PEEG) region (PEEG; 188.50 &#xb1; 0.33 &#x3bc;g GAE/mg E, 144.23 &#xb1; 1.03 &#x3bc;g QE/mg E), respectively. Interestingly, different components were identified, and cynarin was the major compound detected. The PEEG sample exhibited potential antioxidant effects in scavenging ABTS[&#x2022;+] radicals with minimal inhibitory concentration values equal to 10.46 &#xb1; 1.40 &#xb5;g/mL. Furthermore, the highest antibacterial activity was recorded by PEEG against Gram-positive Staphylococcus aureus MDR1. Similarly, PEEG effectively inhibited the biofilm formation of S. aureus MDR1 and the degradation of biofilm was up to 60%. In addition, quorum sensing disruption revealed that both extracts have a moderate capacity for violacein inhibition by the Chromobacterium violaceum ATCC 12472 strain in a concentration-dependent manner.<br><br>CONCLUSION: These findings indicate that propolis can be regarded as a natural therapeutic agent for health problems associated with MDR bacteria and oxidative stress.}, }
@article {pmid38528442, year = {2024}, author = {Hemmati, J and Nazari, M and Abolhasani, FS and Ahmadi, A and Asghari, B}, title = {In vitro investigation of relationship between quorum-sensing system genes, biofilm forming ability, and drug resistance in clinical isolates of Pseudomonas aeruginosa.}, journal = {BMC microbiology}, volume = {24}, number = {1}, pages = {99}, pmid = {38528442}, issn = {1471-2180}, mesh = {Humans ; Quorum Sensing/genetics ; Pseudomonas aeruginosa ; Biofilms ; *Pseudomonas Infections/microbiology ; Drug Resistance, Microbial ; *Cross Infection ; Bacterial Proteins/metabolism ; }, abstract = {BACKGROUND: Pseudomonas aeruginosa is an opportunistic pathogen in the health-care systems and one of the primary causative agents with high mortality in hospitalized patients, particularly immunocompromised. The limitation of effective antibiotic administration in multidrug-resistant and extensively drug-resistant P. aeruginosa isolates leads to the development of nosocomial infections and health problems. Quorum sensing system contributes to biofilm formation, expression of bacterial virulence factors, and development of drug resistance, causing prolonged patient infections. Therefore, due to the significance of the quorum sensing system in increasing the pathogenicity of P. aeruginosa, the primary objective of our study was to investigate the frequency of quorum sensing genes, as well as the biofilm formation and antibiotic resistance pattern among P. aeruginosa strains.<br><br>METHODS: A total of 120 P. aeruginosa isolates were collected from different clinical specimens. The disk diffusion method was applied to detect the antibiotic resistance pattern of P. aeruginosa strains. Also, the microtiter plate method was carried out to evaluate the biofilm-forming ability of isolates. Finally, the frequency of rhlI, rhlR, lasI, and lasR genes was examined by the polymerase chain reaction method.<br><br>RESULTS: In total, 88.3% P. aeruginosa isolates were found to be multidrug-resistant, of which 30.1% had extensively drug-resistant pattern. The highest and lowest resistance rates were found against ceftazidime (75.0%) and ciprofloxacin (46.6%), respectively. Also, 95.8% of isolates were able to produce biofilm, of which 42.5%, 33.3%, and 20.0% had strong, moderate, and weak biofilm patterns, respectively. The frequency of quorum sensing genes among all examined strains was as follows: rhlI (81.6%), rhlR (90.8%), lasI (89.1%), and lasR (78.3%). The most common type of quorum sensing genes among multidrug-resistant isolates were related to rhlR and lasI genes with 94.3%. Furthermore, rhlI, rhlR, and lasI genes were positive for all extensively drug-resistant isolates. However, the lasR gene had the lowest frequency among both multidrug-resistant (83.0%) and extensively drug-resistant (90.6%) isolates. Moreover, rhlR (94.7%) and lasR (81.7%) genes had the highest and lowest prevalence among biofilm-forming isolates, respectively.<br><br>CONCLUSION: Our findings disclosed the significantly high prevalence of drug resistance among P. aeruginosa isolates. Also, the quorum sensing system had a significant correlation with biofilm formation and drug resistance, indicating the essential role of this system in the emergence of nosocomial infections caused by P. aeruginosa.}, }
@article {pmid38527879, year = {2024}, author = {Jiang, X and Wang, M and Yang, S and He, D and Fang, F and Yang, L}, title = {The response of structure and nitrogen removal function of the biofilm on submerged macrophytes to high ammonium in constructed wetlands.}, journal = {Journal of environmental sciences (China)}, volume = {142}, number = {}, pages = {129-141}, doi = {10.1016/j.jes.2023.07.004}, pmid = {38527879}, issn = {1001-0742}, mesh = {Denitrification ; Nitrogen/analysis ; Wetlands ; *Ammonium Compounds ; RNA, Ribosomal, 16S ; Nitrification ; *Cyanobacteria ; Biofilms ; }, abstract = {The ammonium exceedance discharge from sewage treatment plants has a great risk to the stable operation of subsequent constructed wetlands (CWs). The effects of high ammonium shocks on submerged macrophytes and epiphytic biofilms on the leaves of submerged macrophytes in CWs were rarely mentioned in previous studies. In this paper, the 16S rRNA sequencing method was used to investigate the variation of the microbial communities in biofilms on the leaves of Vallisneria natans plants while the growth characteristics of V. natans plants were measured at different initial ammonium concentrations. The results demonstrated that the total chlorophyll and soluble sugar synthesis of V. natans plants decreased by 51.45% and 57.16%, respectively, and malondialdehyde content increased threefold after 8 days if the initial NH4[+]-N concentration was more than 5 mg/L. Algal density, bacterial quantity, dissolved oxygen, and pH increased with high ammonium shocks. The average removal efficiencies of total nitrogen and NH4[+]-N reached 73.26% and 83.94%, respectively. The heat map and relative abundance analysis represented that the relative abundances of phyla Proteobacteria, Cyanobacteria, and Bacteroidetes increased. The numbers of autotrophic nitrifiers and heterotrophic nitrification aerobic denitrification (HNAD) bacteria expanded in biofilms. In particular, HNAD bacteria of Flavobacterium, Hydrogenophaga, Acidovorax, Acinetobacter, Pseudomonas, Aeromonas, and Azospira had higher abundances than autotrophic nitrifiers because there were organic matters secreted from declining leaves of V. natans plants. The analysis of the nitrogen metabolic pathway showed aerobic denitrification was the main nitrogen removal pathway. Thus, the nitrification and denitrification bacterial communities increased in epiphytic biofilms on submerged macrophytes in constructed wetlands while submerged macrophytes declined under ammonium shock loading.}, }
@article {pmid38527516, year = {2024}, author = {Purwasena, IA and Fitri, DK and Putri, DM and Endro, H and Zakaria, MN}, title = {Lipopeptide biosurfactant as a potential root canal irrigation agent: Antimicrobial and anti-biofilm evaluation.}, journal = {Journal of dentistry}, volume = {144}, number = {}, pages = {104961}, doi = {10.1016/j.jdent.2024.104961}, pmid = {38527516}, issn = {1879-176X}, mesh = {*Surface-Active Agents/therapeutic use ; *Root Canal Preparation ; Therapeutic Irrigation/methods ; *Anti-Infective Agents/therapeutic use ; Biofilms/drug effects ; *Lipopeptides/therapeutic use ; Hydrophobic and Hydrophilic Interactions ; Humans ; Bacillus clausii ; Root Canal Therapy/methods ; Biological Products/therapeutic use ; }, abstract = {OBJECTIVES: Lipopeptide Biosurfactant (LB) is a bacteria derived compound able to reduce surface tension between water and hydrophobic substances and exhibit antimicrobial and anti-biofilm properties. This study aimed to investigate the antimicrobial and anti-biofilm effect of a Lipopeptide Biosurfactant (LB) on Enterococcus faecalis, and its potential use in root canal treatment, either as a standalone irrigation solution or in conjunction with sodium hypochlorite (NaOCl).<br><br>METHODS: LB was extracted from Bacillus clausii isolate and the dry extract was diluted in deionized water. The antimicrobial effect of LB against planktonic E. faecalis was evaluated by determining the Minimal Inhibitory Concentration (MIC50). The anti-biofilm effect was evaluated by Minimal Biofilm Inhibitory Concentration (MBIC50) and Minimal Biofilm Eradication Concentration (MBEC50) assays on biofilm grown on dentin specimen surface. To evaluate the effectiveness of LB as a single irrigation solution and as a pre-irrigation prior to NaOCl, live and dead bacterial cells were quantified using Confocal Laser Scanning Microscopy (CLSM), and cell biomass was assessed.<br><br>RESULTS: LB exhibited an MIC50 and MBIC50 of 100 ppm, with an MBEC50 of 1000 ppm, resulting in 52.94 % biofilm inhibition and 60.95 % biofilm eradication on dentin specimens. The effectiveness was concentration-dependent, at 500 ppm, LB demonstrated comparable antimicrobial efficacy to 2.5 % NaOCl. Pre-irrigation with LB resulted in lower biofilm biomass compared to NaOCl alone.<br><br>CONCLUSION: Pre-irrigation with LB enhanced the antimicrobial effect when followed by NaOCl irrigation. Consequently, LB shows promise as both a standalone root canal irrigation solution and as an adjunct to NaOCl in root canal treatment.<br><br>CLINICAL SIGNIFICANCE: The study highlights the potential of Lipopeptide Biosurfactant (LB) as an environmentally friendly irrigation solution for root canal treatment, demonstrating potent antimicrobial and anti-biofilm properties against Enterococcus faecalis. LB exhibits concentration-dependent efficacy comparable to 2.5 % NaOCl and can be used as a standalone irrigation solution or in conjunction with NaOCl.}, }
@article {pmid38526664, year = {2024}, author = {Roy, R and Paul, P and Chakraborty, P and Malik, M and Das, S and Chatterjee, S and Maity, A and Dasgupta, M and Sarker, RK and Sarkar, S and Das Gupta, A and Tribedi, P}, title = {Cuminaldehyde and Tobramycin Forestall the Biofilm Threats of Staphylococcus aureus: A Combinatorial Strategy to Evade the Biofilm Challenges.}, journal = {Applied biochemistry and biotechnology}, volume = {196}, number = {11}, pages = {7588-7613}, pmid = {38526664}, issn = {1559-0291}, support = {R&amp;D/2020/F2//The Neotia University/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; *Tobramycin/pharmacology ; *Staphylococcus aureus/drug effects/physiology ; *Benzaldehydes/pharmacology ; *Cymenes/pharmacology ; *Anti-Bacterial Agents/pharmacology ; Reactive Oxygen Species/metabolism ; Microbial Sensitivity Tests ; Xanthophylls/pharmacology ; Humans ; }, abstract = {Staphylococcus aureus, an opportunistic Gram-positive pathogen, is known for causing various infections in humans, primarily by forming biofilms. The biofilm-induced antibiotic resistance has been considered a significant medical threat. Combinatorial therapy has been considered a reliable approach to combat antibiotic resistance by using multiple antimicrobial agents simultaneously, targeting bacteria through different mechanisms of action. To this end, we examined the effects of two molecules, cuminaldehyde (a natural compound) and tobramycin (an antibiotic), individually and in combination, against staphylococcal biofilm. Our experimental observations demonstrated that cuminaldehyde (20 μg/mL) in combination with tobramycin (0.05 μg/mL) exhibited efficient reduction in biofilm formation compared to their individual treatments (p < 0.01). Additionally, the combination showed an additive interaction (fractional inhibitory concentration value 0.66) against S. aureus. Further analysis revealed that the effective combination accelerated the buildup of reactive oxygen species (ROS) and increased the membrane permeability of the bacteria. Our findings also specified that the cuminaldehyde in combination with tobramycin efficiently reduced biofilm-associated pathogenicity factors of S. aureus, including fibrinogen clumping ability, hemolysis property, and staphyloxanthin production. The selected concentrations of tobramycin and cuminaldehyde demonstrated promising activity against the biofilm development of S. aureus on catheter models without exerting antimicrobial effects. In conclusion, the combination of tobramycin and cuminaldehyde presented a successful strategy for combating staphylococcal biofilm-related healthcare threats. This combinatorial approach holds the potential for controlling biofilm-associated infections caused by S. aureus.}, }
@article {pmid38526390, year = {2025}, author = {Huang, D and Liu, J and Yang, J and Liang, J and Zhang, J and Han, Q and Yu, J and Yang, T and Meng, Q and Steinberg, T and Li, C and Chang, Z}, title = {Restoration of Pregnancy Function Using a GT/PCL Biofilm in a Rabbit Model of Uterine Injury.}, journal = {Tissue engineering. Part A}, volume = {31}, number = {1-2}, pages = {29-44}, doi = {10.1089/ten.TEA.2023.0366}, pmid = {38526390}, issn = {1937-335X}, mesh = {Animals ; *Pregnancy ; *Endometrium/injuries/physiology/surgery ; *Myometrium/injuries/physiology/surgery ; *Gelatin ; *Polyesters ; Regeneration ; *Biofilms ; *Guided Tissue Regeneration/methods ; Models, Animal ; *Tissue Scaffolds ; }, abstract = {Biomaterial scaffolds have been used successfully to promote the regenerative repair of small endometrial lesions in small rodents, providing partial restoration of gestational function. The use of rabbits in this study allowed us to investigate a larger endometrial tissue defect and myometrial injury model. A gelatin/polycaprolactone (GT/PCL) gradient-layer biofilm was sutured at the defect to guide the reconstruction of the original tissue structure. Twenty-eight days postimplantation, the uterine cavity had been restored to its original morphology, endometrial growth was accompanied by the formation of glands and blood vessels, and the fragmented myofibers of the uterine smooth muscle had begun to resemble the normal structure of the lagomorph uterine cavity, arranging in a circular luminal pattern and a longitudinal serosal pattern. In addition, the repair site supported both embryonic implantation into the placenta and normal embryonic development. Four-dimensional label-free proteomic analysis identified the cell adhesion molecules, phagosome, ferroptosis, rap1 signaling pathways, hematopoietic cell lineage, complement and coagulation cascades, tricarboxylic acid cycle, carbon metabolism, and hypoxia inducible factor (HIF)-1 signaling pathways as important in the endogenous repair process of uterine tissue injury, and acetylation of protein modification sites upregulated these signaling pathways.}, }
@article {pmid38525143, year = {2024}, author = {Roselló, J and Llorens-Molina, JA and Larran, S and Sempere-Ferre, F and Santamarina, MP}, title = {Biofilm containing the Thymus serpyllum essential oil for rice and cherry tomato conservation.}, journal = {Frontiers in plant science}, volume = {15}, number = {}, pages = {1362569}, pmid = {38525143}, issn = {1664-462X}, abstract = {INTRODUCTION: Fungal pathogens cause major yield losses in agriculture and reduce food quality and production worldwide.<br><br>PURPOSE: To evaluate new safer alternatives to chemicals for disease management and preserve the shelf life of food, this research was conducted to: determine the chemical composition of the essential oils (EOs) of Thymus serpyllum and Thymus piperella chemotypes 1 and 2; investigate the antifungal potential of EOs in vitro against: Alternaria alternata, Bipolaris spicifera, Curvularia hawaiiensis, Fusarium oxysporum f. sp. lycopersici, Penicillium italicum, Botryotinia fuckeliana; evaluate a natural T. serpyllum extract biofilm to conserve rice grain and cherry tomatoes.<br><br>METHOD: EOs were analyzed by GC-MS+GC-FID. EOs' antifungal activity was evaluated by dissolving Thymus extracts in PDA. Petri dishes were inoculated with disks of each fungus and incubated at 25&#xb0;C for 7 days.<br><br>RESULTS: The T. serpyllum EO displayed the best Mycelial Growth Inhibition. The antifungal effect of the T. serpyllum EO biofilm was evaluated on rice caryopsis. Disinfected grains were dipped in a conidial suspension of each fungus and sprayed with EO (300 and 600 &#x3bc;g/mL) prepared in Tween 20. Grains were stored. The percentage of infected grains was recorded for 30 days. The T. serpyllum EO effect on cherry tomato conservation was evaluated in vivo. Wounded fruit were immersed in the T. serpyllum EO (300 and 400 &#x3bc;g/mL) and inoculated with Fusarium oxysporum f. sp. lycopersici. Fruit were evaluated for 7 and 14 days. Chemical profiles thymol/carvacrol for T. serpyllum, carvacrol for T. piperella Tp1 and thymol for T. piperella Tp2 were defined. The three evaluated EOs reduced all the studied phytopathogens' fungal growth. The T. serpyllum biofilm was effective with rice storage and against Fusarium oxysporum f. sp. lycopersici for extending the shelf life of tomatoes in warehouses and storing postharvest cherry tomatoes.<br><br>CONCLUSION: We suggest applying these EOs as biofilms for safe food conservation to replace synthetic products.}, }
@article {pmid38525010, year = {2024}, author = {Ling, Y and Duan, M and Lyu, W and Yang, J and Liu, Y and Ren, S and Wu, W}, title = {Electrospun L-Lysine/Amorphous Calcium Phosphate Loaded Core-Sheath Nanofibers for Managing Oral Biofilm Infections and Promoting Periodontal Tissue Repairment.}, journal = {International journal of nanomedicine}, volume = {19}, number = {}, pages = {2917-2938}, pmid = {38525010}, issn = {1178-2013}, mesh = {Rats ; Animals ; *Osteogenesis ; Lysine/metabolism ; *Nanofibers ; Cell Differentiation ; Anti-Bacterial Agents/pharmacology/metabolism ; Periodontal Ligament ; *Calcium Phosphates ; }, abstract = {INTRODUCTION: Periodontitis, a chronic inflammatory disease prevalent worldwide, is primarily treated through GTR for tissue regeneration. The efficacy of GTR, however, remains uncertain due to potential infections and the intricate microenvironment of periodontal tissue. Herein, We developed a novel core-shell structure multifunctional membrane using a dual-drug-loaded coaxial electrospinning technique (Lys/ACP-CNF), contains L-lysine in the outer layer to aid in controlling biofilms after GTR regenerative surgery, and ACP in the inner layer to enhance osteogenic performance for accelerating alveolar bone repair.<br><br>METHODS: The biocompatibility and cell adhesion were evaluated through CCK-8 and fluorescence imaging, respectively. The antibacterial activity was assessed using a plate counting assay. ALP, ARS, and RT-qPCR were used to examine osteogenic differentiation. Additionally, an in vivo experiment was conducted on a rat model with acute periodontal defect and infection. Micro-CT and histological analysis were utilized to analyze the in vivo alveolar bone regeneration.<br><br>RESULTS: Structural and physicochemical characterization confirmed the successful construction of the core-shell fibrous structure. Additionally, the Lys/ACP-CNF showed strong antibacterial coaggregation effects and induced osteogenic differentiation of PDLSCs in vitro. The in vivo experiment confirmed that Lys/ACP-CNF promotes new bone formation.<br><br>CONCLUSION: Lys/ACP-CNF rapidly exhibited excellent antibacterial activity, protected PDLSCs from infection, and was conducive to osteogenesis, demonstrating its potential application for clinical periodontal GTR surgery.}, }
@article {pmid38522670, year = {2024}, author = {Wang, X and Wang, T and Meng, H and Xing, F and Yun, H}, title = {Anammox process in anaerobic baffled biofilm reactors with columnar packings: Characteristics of flow field and microbial community.}, journal = {Chemosphere}, volume = {355}, number = {}, pages = {141774}, doi = {10.1016/j.chemosphere.2024.141774}, pmid = {38522670}, issn = {1879-1298}, mesh = {Anaerobiosis ; *Bioreactors/microbiology ; Sewage/microbiology ; Anaerobic Ammonia Oxidation ; Bacteria/metabolism ; *Microbiota ; Biofilms ; Nitrogen/metabolism ; Oxidation-Reduction ; Denitrification ; }, abstract = {The enrichment of anammox bacteria is a key issue in the application of anammox processes. A new type of reactor － anaerobic baffle biofilm reactor (ABBR) developed from anaerobic baffle reactor (ABR) was filled with columnar packings and established for effective enrichment of anammox bacteria. The flow field analysis showed that, compared with ABR, ABBR narrowed the dead zone so as to improve the substrate transferring performances. Two ABBRs with different types of columnar packings (Packings 1 and Packings 2) were constructed to culture anammox biofilms. Packings 1 consisted of the single-form honeycomb carriers while Packings 2 was modular composite packings consisting of non-woven fabric and honeycomb carriers. The effects of different types of columnar packings on microbial community and nitrogen removal were studied. The ABBR filled with Packings 2 had a higher retention rate of biomass than the ABBR filled with Packings 1, making the anammox start-up period be shortened by 21.28%. The enrichment of anammox bacteria were achieved and the dominant anammox bacteria were Candidatus Brocadia in both R1 and R2. However, there were four genera of anammox bacteria in R2 and one genus of anammox bacteria in R1, and the cell density of anammox bacteria in R2 was 95% higher than that in R1. R2 has the advantage of maintaining excellent and stable nitrogen removal performance at high nitrogen loading rate. The results revealed that the packings composed of two types of carriers may have a better enrichment effect on anammox bacteria. This study is of great significance for the rapid enrichment of anammox bacteria and the technical promotion of anammox process.}, }
@article {pmid38522282, year = {2024}, author = {Li, H and Zeng, X and Yao, T and Xu, H}, title = {An antimicrobial film of silver/nanocellulose crystal/oxalic acid/polyvinyl alcohol with real-time bactericidal and prevention of biofilm formation properties.}, journal = {Colloids and surfaces. B, Biointerfaces}, volume = {237}, number = {}, pages = {113868}, doi = {10.1016/j.colsurfb.2024.113868}, pmid = {38522282}, issn = {1873-4367}, mesh = {Silver/pharmacology/chemistry ; Polyvinyl Alcohol/chemistry ; *Metal Nanoparticles/chemistry ; Oxalic Acid/pharmacology ; Escherichia coli ; Staphylococcus aureus ; Anti-Bacterial Agents/pharmacology/chemistry ; *Anti-Infective Agents/pharmacology ; Biofilms ; }, abstract = {Silver nanoparticles (AgNPs) is an excellent antibacterial agent, which is widely used in medical, food, environmental and other fields, but AgNPs are easy to accumulate in aqueous solution, so their application in various fields is limited. Therefore, it is particularly important to propose a new application method or to prepare a new composite material. In this study, OA/PVA was obtained by cross-linking oxalic acid (OA) with polyvinyl alcohol (PVA). Then Ag/NCC was obtained by in situ reduction of AgNPs on nanocellulose crystals (NCC). Finally, Ag/NCC/OA/PVA composite antimicrobial films with good waterproofing effect were prepared by mixing Ag/NCC with OA/PVA. Subsequently, the films were characterized using SEM, UV-vis, FTIR and XRD, as well as physicochemical properties such as mechanical strength and hydrophilic properties were determined. The results indicated that the Ag/NCC/OA/PVA films possess good light transmittance, mechanical properties, water resistance, antibacterial activity, and biodegradability. The results of the mechanism study showed that Ag/NCC/OA/PVA films can destroy cell integrity, inhibit succinate dehydrogenase (SDH) activity, thereby reducing intracellular ATP levels. And induce a large number of reactive oxygen species (ROS) production, eventually leading to the death of C. sakazakii. In summary, Ag/NCC/OA/PVA film has good physical and chemical properties, antibacterial activity and biocompatibility, and has promising applications in food and medical antibacterial fields.}, }
@article {pmid38521769, year = {2024}, author = {Yaeger, LN and Ranieri, MRM and Chee, J and Karabelas-Pittman, S and Rudolph, M and Giovannoni, AM and Harvey, H and Burrows, LL}, title = {A genetic screen identifies a role for oprF in Pseudomonas aeruginosa biofilm stimulation by subinhibitory antibiotics.}, journal = {NPJ biofilms and microbiomes}, volume = {10}, number = {1}, pages = {30}, pmid = {38521769}, issn = {2055-5008}, support = {RGPIN-2021-04237//Gouvernement du Canada | Natural Sciences and Engineering Research Council of Canada (Conseil de Recherches en Sciences Naturelles et en G&#xe9;nie du Canada)/ ; PGS-D//Gouvernement du Canada | Natural Sciences and Engineering Research Council of Canada (Conseil de Recherches en Sciences Naturelles et en G&#xe9;nie du Canada)/ ; USRA//Gouvernement du Canada | Natural Sciences and Engineering Research Council of Canada (Conseil de Recherches en Sciences Naturelles et en G&#xe9;nie du Canada)/ ; }, mesh = {Humans ; *Anti-Bacterial Agents/pharmacology/metabolism ; Bacterial Proteins/genetics/metabolism ; Biofilms ; Disulfides/metabolism ; Escherichia coli/metabolism ; Phosphoric Diester Hydrolases ; *Pseudomonas aeruginosa/genetics/physiology ; *Pseudomonas Infections ; }, abstract = {Biofilms are surface-associated communities of bacteria that grow in a self-produced matrix of polysaccharides, proteins, and extracellular DNA (eDNA). Sub-minimal inhibitory concentrations (sub-MIC) of antibiotics induce biofilm formation, potentially as a defensive response to antibiotic stress. However, the mechanisms behind sub-MIC antibiotic-induced biofilm formation are unclear. We show that treatment of Pseudomonas aeruginosa with multiple classes of sub-MIC antibiotics with distinct targets induces biofilm formation. Further, addition of exogenous eDNA or cell lysate failed to increase biofilm formation to the same extent as antibiotics, suggesting that the release of cellular contents by antibiotic-driven bacteriolysis is insufficient. Using a genetic screen for stimulation-deficient mutants, we identified the outer membrane porin OprF and the ECF sigma factor SigX as important. Similarly, loss of OmpA - the Escherichia coli OprF homolog - prevented sub-MIC antibiotic stimulation of E. coli biofilms. Our screen also identified the periplasmic disulfide bond-forming enzyme DsbA and a predicted cyclic-di-GMP phosphodiesterase encoded by PA2200 as essential for biofilm stimulation. The phosphodiesterase activity of PA2200 is likely controlled by a disulfide bond in its regulatory domain, and folding of OprF is influenced by disulfide bond formation, connecting the mutant phenotypes. Addition of reducing agent dithiothreitol prevented sub-MIC antibiotic biofilm stimulation. Finally, activation of a c-di-GMP-responsive promoter follows treatment with sub-MIC antibiotics in the wild-type but not an oprF mutant. Together, these results show that antibiotic-induced biofilm formation is likely driven by a signaling pathway that translates changes in periplasmic redox state into elevated biofilm formation through increases in c-di-GMP.}, }
@article {pmid38521361, year = {2024}, author = {Tiraboschi, G and Isaac, P and Breser, ML and Angiolini, V and Rodriguez-Berdini, L and Porporatto, C and Bohl, LP}, title = {1,25 dihydroxyvitamin D3-mediated effects on bovine innate immunity and on biofilm-forming Staphylococcus spp. isolated from cattle with mastitis.}, journal = {The Journal of steroid biochemistry and molecular biology}, volume = {240}, number = {}, pages = {106508}, doi = {10.1016/j.jsbmb.2024.106508}, pmid = {38521361}, issn = {1879-1220}, mesh = {Animals ; Cattle ; *Biofilms/drug effects/growth &amp; development ; Female ; *Mastitis, Bovine/microbiology/immunology ; *Immunity, Innate/drug effects ; *Staphylococcus/drug effects ; *Phagocytosis/drug effects ; Calcitriol/pharmacology ; Staphylococcal Infections/microbiology/veterinary/immunology/drug therapy ; Cell Line ; Mammary Glands, Animal/microbiology/immunology ; Macrophages/microbiology/drug effects/immunology/metabolism ; }, abstract = {Mastitis is one the most widespread and serious diseases in dairy cattle. Recurrent and chronic infections are often attributable to certain pathogenicity mechanisms in mastitis-causing pathogens such as Staphylococcus spp. These include growing in biofilm and invading cells, both of which make it possible to resist or evade antimicrobial therapies and the host's immune system. This study tested the effects of active vitamin D3 (i.e., calcitriol or 1,25-dihydroxyvitamin D3) on the internalization and phagocytosis of biofilm-forming Staphylococcus spp. isolated from animals with mastitis. Two established bovine cell lines were used: MAC-T (mammary epithelial cells) and BoMac (macrophages). Calcitriol (0-200 nM) did not affect the viability of MAC-T cells nor that of BoMac cells after 24 and 72 h. Concentrations of 0-100 mM for 24 h upregulated the expression of 24-hydroxylase in MAC-T cells, but did not alter that of VDR. Pre-treatment of the cells with calcitriol for 24 h decreased the internalization of S. aureus V329 into MAC-T cells (0-100 nM), and stimulated the phagocytosis of the same strain and of S. xylosus 4913 (0-10 nM). Calcitriol and two conditioned media, obtained by treating the cells with 25-200 nM of the metabolite for 24 h, were also assessed in terms of their antimicrobial and antibiofilm activity. Neither calcitriol by itself nor the conditioned media affected staphylococcal growth or biofilm formation (0-200 nM for 12 and 24 h, respectively). In contrast, the conditioned media (0-100 nM for 24 h) decreased the biomass of preformed non-aureus staphylococcal biofilms and killed the bacteria within them, without affecting metabolic activity. These effects may be mediated by reactive oxygen species and proteins with antimicrobial and/or antibiofilm activity. In short, calcitriol could make pathogens more accessible to antimicrobial therapies and enhance bacterial clearance by professional phagocytes. Moreover, it may modulate the host's endogenous defenses in the bovine udder and help combat preformed non-aureus staphylococcal biofilms (S. chromogenes 40, S. xylosus 4913, and/or S. haemolyticus 6). The findings confirm calcitriol's potential as an adjuvant to prevent and/or treat intramammary infections caused by Staphylococcus spp., which would in turn contribute to reducing antibiotic use on dairy farms.}, }
@article {pmid38521108, year = {2024}, author = {Zhang, C and Zeng, X and Xu, X and Nie, W and Dubey, BK and Ding, W}, title = {PDA-Fe3O4 decorated carbon felt anode enhancing electrochemical performance of microbial fuel cells: Effect of electrode materials on electroactive biofilm.}, journal = {Chemosphere}, volume = {355}, number = {}, pages = {141764}, doi = {10.1016/j.chemosphere.2024.141764}, pmid = {38521108}, issn = {1879-1298}, mesh = {*Bioelectric Energy Sources ; Carbon/chemistry ; Carbon Fiber ; Electricity ; Electrodes ; Biofilms ; *Indoles ; *Polymers ; }, abstract = {Anode modification is an effective strategy for enhancing the electrochemical performance of microbial fuel cell (MFC). However, the impacts of the modified materials on anode biofilm development during MFC operation have been less studied. We prepared a novel PDA-Fe3O4-CF composite anode by coating original carbon felt anode (CF) with polydopamine (PDA) and Fe3O4 nanoparticles. The composite anode material was characterized by excellent hydrophilicity and electrical conductivity, and the anodic biofilm exhibited fast start-up, higher biomass, and more uniform biofilm layer after MFC operation. The MFC reactor assembled with the composite anode achieved a maximum power density of 608 mW m[-2] and an output voltage of 586 mV, which were 316.4% and 72.4% higher than the MFC with the original CF anode, respectively. Microbial community analysis indicated that the modified anode biofilm had a higher relative abundance of exoelectrogen species in comparison to the unmodified anode. The PICRUSt data revealed that the anodic materials may affect the bioelectrochemical performance of the biofilm by influencing the expression levels of key enzyme genes involved in biofilm extracellular polymer (EPS) secretion and extracellular electron transfer (EET). The growth of the anodic biofilm would exert positive or negative influences on the efficiency of electricity production and electron transfer of the MFCs at different operating stages. This work expands the knowledge of the role that anodic materials play in the development and electrochemical performance of anodic biofilm in MFCs.}, }
@article {pmid38520779, year = {2024}, author = {Zhang, Z and Li, D and Zhou, C and Huang, X and Chen, Y and Wang, S and Liu, G}, title = {Enhanced nitrogen removal via partial nitrification/denitrification coupled Anammox using three stage anoxic/oxic biofilm process with intermittent aeration.}, journal = {Water research}, volume = {255}, number = {}, pages = {121491}, doi = {10.1016/j.watres.2024.121491}, pmid = {38520779}, issn = {1879-2448}, abstract = {Pre-capturing organics in municipal wastewater for biogas production, combined with Anammox-based nitrogen removal process, improves the sustainability of sewage treatment. Thus, enhancing nitrogen removal via Anammox in mainstream wastewater treatment becomes very crucial. In present study, a three-stage anoxic/oxic (AO) biofilm process with intermittent aeration was designed to strengthen partial nitrification/denitrification coupling Anammox (PNA/PDA) in treatment of low C/N wastewater, which contained chemical oxygen demand (COD) of 79.8 mg/L and total inorganic nitrogen (TIN) of 58.9 mg/L. With a hydraulic retention time of 8.0 h, the process successfully reduced TIN to 10.6 mg/L, achieving a nitrogen removal efficiency of 83.3 %. The 1[st] anoxic zone accounted for 32.0 % TIN removal, with 10.3 % by denitrification and 21.7 % by PDA, meanwhile, the 2[nd] and 3[rd] anoxic zones contributed 19.4 % and 4.5 % of TIN removal, primarily achieved through PDA (including endogenous PD coupling Anammox). The 1[st] and 2[nd] intermittent zones accounted for 27.2 % and 17.0 % of TIN removal, respectively, with 13.7 %-21.3 % by PNA and 3.2 %-5.3 % by PDA. Although this process did not pursue nitrite accumulation in any zone (< 1.5 mg-N/L), PNA and PDA accounted for 35.1 % and 52.1 % of TIN removal, respectively. Only 0.21 % of removed TIN was released as nitrous oxide. The AnAOB of Candidatus Brocadia was enriched in each zone, with a relative abundance of 0.66 %-2.29 %. In intermittent zones, NOB had been partially suppressed (AOB/NOB = 0.73-0.88), mainly due to intermittent aeration and effective nitrite utilization by AnAOB since its population size was much greater than NOB. Present study indicated that the three-stage AO biofilm process with intermittent aeration could enhance nitrogen removal via PNA and PDA with a low N2O emission factor.}, }
@article {pmid38520490, year = {2024}, author = {Polyudova, T and Lemkina, L and Eroshenko, D and Esaev, A}, title = {Suppression of planktonic and biofilm of Escherichia coli by the synergistic lantibiotics-polymyxins combinations.}, journal = {Archives of microbiology}, volume = {206}, number = {4}, pages = {191}, pmid = {38520490}, issn = {1432-072X}, mesh = {Polymyxins/pharmacology ; Polymyxin B/pharmacology ; Anti-Bacterial Agents/pharmacology ; *Nisin/pharmacology ; Escherichia coli/genetics ; Plankton ; *Bacteriocins/pharmacology ; Biofilms ; Ions ; Microbial Sensitivity Tests ; }, abstract = {Escherichia coli are generally resistant to the lantibiotic's action (nisin and warnerin), but we have shown increased sensitivity of E. coli to lantibiotics in the presence of subinhibitory concentrations of polymyxins. Synergistic lantibiotic-polymyxin combinations were found for polymyxins B and M. The killing of cells at the planktonic and biofilm levels was observed for two collection and four clinical multidrug-resistant E. coli strains after treatment with lantibiotic-polymyxin B combinations. Thus, 24-h treatment of E. coli mature biofilms with warnerin-polymyxin B or nisin-polymyxin B leads to five to tenfold decrease in the number of viable cells, depending on the strain. AFM revealed that the warnerin and polymyxin B combination caused the loss of the structural integrity of biofilm and the destruction of cells within the biofilm. It has been shown that pretreatment of cells with polymyxin B leads to an increase of Ca[2+] and Mg[2+] ions in the culture medium, as detected by atomic absorption spectroscopy. The subsequent exposure to warnerin caused cell death with the loss of K[+] ions and cell destruction with DNA and protein release. Thus, polymyxins display synergy with lantibiotics against planktonic and biofilm cells of E. coli, and can be used to overcome the resistance of Gram-negative bacteria to lantibiotics.}, }
@article {pmid38520398, year = {2024}, author = {Kozuka, Y and Masuda, T and Isu, N and Takai, M}, title = {Antimicrobial Peptide Assembly on Zwitterionic Polymer Films to Slow Down Biofilm Formation.}, journal = {Langmuir : the ACS journal of surfaces and colloids}, volume = {40}, number = {13}, pages = {7029-7037}, doi = {10.1021/acs.langmuir.4c00086}, pmid = {38520398}, issn = {1520-5827}, mesh = {*Polymers/pharmacology/chemistry ; *Antimicrobial Peptides ; Escherichia coli ; Biofilms ; Bacterial Adhesion ; Anti-Bacterial Agents/pharmacology/chemistry ; }, abstract = {Formation of biofilms on equipment used in various fields, such as medicine, domestic sanitation, and marine transportation, can cause serious problems. The use of antibiofouling and bactericidal modifications is a promising strategy for inhibiting bacterial adhesion and biofilm formation. To further enhance the antibiofilm properties of a surface, various combinations of bactericidal modifications alongside antibiofouling modifications have been developed. Optimization of the arrangements of antimicrobial peptides on the antibiofouling surface would allow us to design longer-life antibiofilm surface modifications. In this study, a postmodification was conducted with different design using the antimicrobial peptide KR12 on an antibiofouling copolymer film consisting of 2-methacryloyloxyethyl phosphorylcholine, 3-methacryloxypropyl trimethoxysilane, and 3-(methacryloyloxy) propyl-tris(trimethylsilyloxy) silane. The distance of KR12 from the film was adjusted by combining different lengths of poly(ethylene glycol) (PEG) spacers (molecular weights are 2000 and 5000). The density of KR12 was ranged from 0.06 to 0.22 nm[-2]. When these modified surfaces were exposed to a nutrient-rich TSB suspension, the bacterial area formed by E. coli covered 5-127% of the original copolymer film. We found that a significant distance between the bactericidal and antibiofouling modifications, along with a higher density of bactericidal modifications, slows down the biofilm formation.}, }
@article {pmid38519959, year = {2024}, author = {Aboelnaga, N and Elsayed, SW and Abdelsalam, NA and Salem, S and Saif, NA and Elsayed, M and Ayman, S and Nasr, M and Elhadidy, M}, title = {Deciphering the dynamics of methicillin-resistant Staphylococcus aureus biofilm formation: from molecular signaling to nanotherapeutic advances.}, journal = {Cell communication and signaling : CCS}, volume = {22}, number = {1}, pages = {188}, pmid = {38519959}, issn = {1478-811X}, mesh = {Humans ; *Methicillin-Resistant Staphylococcus aureus/physiology ; Staphylococcus aureus ; *Staphylococcal Infections/drug therapy/microbiology ; Biofilms ; Quorum Sensing/genetics ; }, abstract = {Methicillin-resistant Staphylococcus aureus (MRSA) represents a global threat, necessitating the development of effective solutions to combat this emerging superbug. In response to selective pressures within healthcare, community, and livestock settings, MRSA has evolved increased biofilm formation as a multifaceted virulence and defensive mechanism, enabling the bacterium to thrive in harsh conditions. This review discusses the molecular mechanisms contributing to biofilm formation across its developmental stages, hence representing a step forward in developing promising strategies for impeding or eradicating biofilms. During staphylococcal biofilm development, cell wall-anchored proteins attach bacterial cells to biotic or abiotic surfaces; extracellular polymeric substances build scaffolds for biofilm formation; the cidABC operon controls cell lysis within the biofilm, and proteases facilitate dispersal. Beside the three main sequential stages of biofilm formation (attachment, maturation, and dispersal), this review unveils two unique developmental stages in the biofilm formation process for MRSA; multiplication and exodus. We also highlighted the quorum sensing as a cell-to-cell communication process, allowing distant bacterial cells to adapt to the conditions surrounding the bacterial biofilm. In S. aureus, the quorum sensing process is mediated by autoinducing peptides (AIPs) as signaling molecules, with the accessory gene regulator system playing a pivotal role in orchestrating the production of AIPs and various virulence factors. Several quorum inhibitors showed promising anti-virulence and antibiofilm effects that vary in type and function according to the targeted molecule. Disrupting the biofilm architecture and eradicating sessile bacterial cells are crucial steps to prevent colonization on other surfaces or organs. In this context, nanoparticles emerge as efficient carriers for delivering antimicrobial and antibiofilm agents throughout the biofilm architecture. Although metal-based nanoparticles have been previously used in combatting biofilms, its non-degradability and toxicity within the human body presents a real challenge. Therefore, organic nanoparticles in conjunction with quorum inhibitors have been proposed as a promising strategy against biofilms. As nanotherapeutics continue to gain recognition as an antibiofilm strategy, the development of more antibiofilm nanotherapeutics could offer a promising solution to combat biofilm-mediated resistance.}, }
@article {pmid38519175, year = {2024}, author = {Fan, L and Dai, H and Zhou, W and Yuan, L and Yang, J and Yang, Z and Jiao, XA}, title = {Unraveling the significance of calcium as a biofilm promotion signal for Bacillus licheniformis strains isolated from dairy products.}, journal = {Food research international (Ottawa, Ont.)}, volume = {182}, number = {}, pages = {114145}, doi = {10.1016/j.foodres.2024.114145}, pmid = {38519175}, issn = {1873-7145}, mesh = {*Bacillus licheniformis/genetics ; Calcium ; Dairy Products/microbiology ; Biofilms ; Bacteria/genetics ; Polysaccharides ; RNA ; }, abstract = {Bacillus licheniformis, a quick and strong biofilm former, is served as a persistent microbial contamination in the dairy industry. Its biofilm formation process is usually regulated by environmental factors including the divalent cation Ca[2+]. This work aims to investigate how different concentrations of Ca[2+] change biofilm-related phenotypes (bacterial motility, biofilm-forming capacity, biofilm structures, and EPS production) of dairy B. licheniformis strains. The Ca[2+] ions dependent regulation mechanism for B. licheniformis biofilm formation was further investigated by RNA-sequencing analysis. Results revealed that supplementation of Ca[2+] increased B. licheniformis biofilm formation in a dose-dependent way, and enhanced average coverage and thickness of biofilms with complex structures were observed by confocal laser scanning microscopy. Bacterial mobility of B. licheniformis was increased by the supplementation of Ca[2+] except the swarming ability at 20 mM of Ca[2+]. The addition of Ca[2+] decreased the contents of polysaccharides but promoted proteins production in EPS, and the ratio of proteins/polysaccharides content was significantly enhanced with increasing Ca[2+] concentrations. RNA-sequencing results clearly indicated the variation in regulating biofilm formation under different Ca[2+] concentrations, as 939 (671 upregulated and 268 downregulated) and 951 genes (581 upregulated and 370 downregulated) in B. licheniformis BL2-11 were induced by 10 and 20 mM of Ca[2+], respectively. Differential genes were annotated in various KEGG pathways, including flagellar assembly, two-component system, quorum sensing, ABC transporters, and related carbohydrate and amino acid metabolism pathways. Collectively, the results unravel the significance of Ca[2+] as a biofilm-promoting signal for B. licheniformis in the dairy industry.}, }
@article {pmid38518879, year = {2024}, author = {Sheng, M and Ye, Z and Zhu, F and Pan, D and Shao, S and Wu, X}, title = {New insights into nitrogen removal by divalent iron-enhanced moving bed biofilm reactor: Performance, interfacial interaction and co-occurrence network.}, journal = {Bioresource technology}, volume = {399}, number = {}, pages = {130621}, doi = {10.1016/j.biortech.2024.130621}, pmid = {38518879}, issn = {1873-2976}, mesh = {*Denitrification ; *Nitrogen ; Bioreactors/microbiology ; Nitrification ; Biofilms ; }, abstract = {A divalent iron-mediated moving bed biofilm reactor with intermittent aeration was developed to enhance the nitrogen removal at low carbon-to-nitrogen ratios. The study demonstrated thatammonia removal increased from 51 ± 4 % to 79 ± 4 % and nitrate removal increased from 72 ± 5 % to 98 ± 4 % in phases I-IV, and 2-5 mg·L[-1] of divalent iron significantly increased the anoxic denitrification process. Divalent iron stimulated the secretion of extracellular polymeric substances, which facilitated the formation of cross-linked network between microbial cells. Furthermore, the cycle between divalent and trivalent iron decreased the energy barrier between the biofilm and the pollutant. The microbial community further revealed that Proteobacteria (relative abundance: 40-48 %) andBacteroidota(relative abundance: 31-37 %) were the dominant phyla, supporting the synchronous nitrification and denitrification processes as well as the lower accumulation of nitrite. In conclusion, iron redox cycling significantly enhanced the nitrogen removal. This study proposes a viable strategy for the efficient treatment of nutrient wastewater.}, }
@article {pmid38518822, year = {2024}, author = {Colas, S and Marie, B and Morin, S and Milhe-Poutingon, M and Foucault, P and Chalvin, S and Gelber, C and Baldoni-Andrey, P and Gurieff, N and Fortin, C and Le Faucheur, S}, title = {New sensitive tools to characterize meta-metabolome response to short- and long-term cobalt exposure in dynamic river biofilm communities.}, journal = {The Science of the total environment}, volume = {927}, number = {}, pages = {171851}, doi = {10.1016/j.scitotenv.2024.171851}, pmid = {38518822}, issn = {1879-1026}, mesh = {*Biofilms/drug effects ; *Cobalt/toxicity ; *Rivers/microbiology ; *Water Pollutants, Chemical/toxicity ; *Metabolome/drug effects ; Metabolomics ; Microbiota/drug effects ; }, abstract = {Untargeted metabolomics is a non-a priori analysis of biomolecules that characterizes the metabolome variations induced by short- and long-term exposures to stressors. Even if the metabolite annotation remains lacunar due to database gaps, the global metabolomic fingerprint allows for trend analyses of dose-response curves for hundreds of cellular metabolites. Analysis of dose/time-response curve trends (biphasic or monotonic) of untargeted metabolomic features would thus allow the use of all the chemical signals obtained in order to determine stress levels (defense or damage) in organisms. To develop this approach in a context of time-dependent microbial community changes, mature river biofilms were exposed for 1 month to four cobalt (Co) concentrations (from background concentration to 1 × 10[-6] M) in an open system of artificial streams. The meta-metabolomic response of biofilms was compared against a multitude of biological parameters (including bioaccumulation, biomass, chlorophyll a content, composition and structure of prokaryotic and eukaryotic communities) monitored at set exposure times (from 1 h to 28 d). Cobalt exposure induced extremely rapid responses of the meta-metabolome, with time range inducing defense responses (TRIDeR) of around 10 s, and time range inducing damage responses (TRIDaR) of several hours. Even in biofilms whose structure had been altered by Co bioaccumulation (reduced biomass, chlorophyll a contents and changes in the composition and diversity of prokaryotic and eukaryotic communities), concentration range inducing defense responses (CRIDeR) with similar initiation thresholds (1.41 ± 0.77 × 10[-10] M Co[2+] added in the exposure medium) were set up at the meta-metabolome level at every time point. In contrast, the concentration range inducing damage responses (CRIDaR) initiation thresholds increased by 10 times in long-term Co exposed biofilms. The present study demonstrates that defense and damage responses of biofilm meta-metabolome exposed to Co are rapidly and sustainably impacted, even within tolerant and resistant microbial communities.}, }
@article {pmid38518773, year = {2024}, author = {Granton, E and Brown, L and Defaye, M and Moazen, P and Almblad, H and Randall, TE and Rich, JD and Geppert, A and Abdullah, NS and Hassanabad, MF and Hiroki, CH and Farias, R and Nguyen, AP and Schubert, C and Lou, Y and Andonegui, G and Iftinca, M and Raju, D and Vargas, MA and Howell, PL and Füzesi, T and Bains, J and Kurrasch, D and Harrison, JJ and Altier, C and Yipp, BG}, title = {Biofilm exopolysaccharides alter sensory-neuron-mediated sickness during lung infection.}, journal = {Cell}, volume = {187}, number = {8}, pages = {1874-1888.e14}, doi = {10.1016/j.cell.2024.03.001}, pmid = {38518773}, issn = {1097-4172}, mesh = {Animals ; Female ; Male ; Mice ; Biofilms ; *Escherichia coli/physiology ; Hypothermia/metabolism/pathology ; Inflammation/metabolism/pathology ; *Lung/microbiology/pathology ; Pneumonia/microbiology/pathology ; *Pseudomonas aeruginosa/physiology ; Sensory Receptor Cells ; *Polysaccharides, Bacterial/metabolism ; *Escherichia coli Infections/metabolism/microbiology/pathology ; *Pseudomonas Infections/metabolism/microbiology/pathology ; Nociceptors/metabolism ; }, abstract = {Infections of the lung cause observable sickness thought to be secondary to inflammation. Signs of sickness are crucial to alert others via behavioral-immune responses to limit contact with contagious individuals. Gram-negative bacteria produce exopolysaccharide (EPS) that provides microbial protection; however, the impact of EPS on sickness remains uncertain. Using genome-engineered Pseudomonas aeruginosa (P. aeruginosa) strains, we compared EPS-producers versus non-producers and a virulent Escherichia coli (E. coli) lung infection model in male and female mice. EPS-negative P. aeruginosa and virulent E. coli infection caused severe sickness, behavioral alterations, inflammation, and hypothermia mediated by TLR4 detection of the exposed lipopolysaccharide (LPS) in lung TRPV1[+] sensory neurons. However, inflammation did not account for sickness. Stimulation of lung nociceptors induced acute stress responses in the paraventricular hypothalamic nuclei by activating corticotropin-releasing hormone neurons responsible for sickness behavior and hypothermia. Thus, EPS-producing biofilm pathogens evade initiating a lung-brain sensory neuronal response that results in sickness.}, }
@article {pmid38516014, year = {2024}, author = {Oliveira, LT and Marcos, CM and Cabral, AKLF and Medina-Alarcón, KP and Pires, RH and Fusco-Almeida, AM and Mendes-Giannini, MJS}, title = {Paracoccidioides spp.: the structural characterization of extracellular matrix, expression of glucan synthesis and associated genes and adhesins during biofilm formation.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1354140}, pmid = {38516014}, issn = {1664-302X}, abstract = {The genus Paracoccidioides includes Paracoccidioides lutzii and the Paracoccidioides brasiliensis complex, which comprises four phylogenetic species. A key feature distinguishing planktonic growth from biofilm is the presence of a 3D extracellular matrix (ECM). Therefore, in this study, we analyzed biofilm formation in different species of Paracoccidioides yeast phase, characterized the structural elements of the matrix of P. brasiliensis (Pb18), P. lutzii (Pl01 and 8334) and P. restrepiensis (339 and 192) and evaluated the expression of glucan genes, according to the stage of biofilm evolution for P. brasiliensis. The strains were cultivated in planktonic and biofilm form for 24-144 h. The fungi biomass and metabolic activity were determined by crystal violet and tetrazolium salt reduction (XTT) tests and colony-forming unit (CFU) by plating. The biofilm structure was designed using scanning electron microscopy and confocal laser scanning microscopy techniques. The extracellular matrix of P. brasiliensis and P. lutzii biofilms was extracted by sonication, and polysaccharides, proteins, and extracellular DNA (eDNA) were quantified. The RNA was extracted with the Trizol[®] reagent and quantified; then, the cDNA was synthesized to analyze the enolase expression, 14-3-3, FKS1, AGS1, GEL3, and KRE6 genes by real-time PCR. All strains of Paracoccidioides studied form a biofilm with more significant metabolic activity and biomass values in 144 h. The extracellular matrix of P. brasiliensis and P. lutzii had a higher content of polysaccharides in their composition, followed by proteins and eDNA in smaller quantities. The P. brasiliensis biofilm kinetics of formation showed greater expression of genes related to glucan's synthesis and its delivery to the external environment in addition adhesins during the biofilm's adhesion, initiation, and maturation. The GEL3 and enolase genes increased in expression within 24 h and during the biofilm maturation period, there was an increase in 14-3-3, AGS1, and FKS1. Furthermore, at 144 h, there was a decrease in KRE6 expression and an increase in GEL3. This study highlights the potential for biofilm formation for three species of Paracoccidioides and the main components of the extracellular matrix that can contribute to a better understanding of biofilm organization.}, }
@article {pmid38516008, year = {2024}, author = {Nicholson, TL and Waack, U and Fleming, DS and Chen, Q and Miller, LC and Merkel, TJ and Stibitz, S}, title = {The contribution of BvgR, RisA, and RisS to global gene regulation, intracellular cyclic-di-GMP levels, motility, and biofilm formation in Bordetella bronchiseptica.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1305097}, pmid = {38516008}, issn = {1664-302X}, abstract = {Bordetella bronchiseptica is a highly contagious respiratory bacterial veterinary pathogen. In this study the contribution of the transcriptional regulators BvgR, RisA, RisS, and the phosphorylation of RisA to global gene regulation, intracellular cyclic-di-GMP levels, motility, and biofilm formation were evaluated. Next Generation Sequencing (RNASeq) was used to differentiate the global gene regulation of both virulence-activated and virulence-repressed genes by each of these factors. The BvgAS system, along with BvgR, RisA, and the phosphorylation of RisA served in cyclic-di-GMP degradation. BvgR and unphosphorylated RisA were found to temporally regulate motility. Additionally, BvgR, RisA, and RisS were found to be required for biofilm formation.}, }
@article {pmid38515541, year = {2024}, author = {Catania, S and Bottinelli, M and Fincato, A and Tondo, A and Matucci, A and Nai, G and Righetti, V and Abbate, F and Ramírez, AS and Gobbo, F and Merenda, M}, title = {Pathogenic avian mycoplasmas show phenotypic differences in their biofilm forming ability compared to non-pathogenic species in vitro.}, journal = {Biofilm}, volume = {7}, number = {}, pages = {100190}, pmid = {38515541}, issn = {2590-2075}, abstract = {Mycoplasmas are known as the minimalist microorganisms in the microbes' world. Their minimalist nature makes them highly sensitive to the environmental conditions and limits their ability to survive for extended periods outside their animal host. Nevertheless, there are documented instances of mycoplasma transmission over significant distances and this phenomenon may be linked to relatively unexplored abilities of mycoplasmas, such as their capacity to synthesize biofilm-the predominant mode of bacterial growth in nature. The authors decided to establish a method aimed at inducing the clustering of mycoplasma planktonic cells within a biofilm in vitro and subsequently assess the capacity of certain avian mycoplasmas to synthesize a biofilm. A total of 299 avian mycoplasma isolates were included in the study, encompassing both pathogenic (Mycoplasma gallisepticum, M. synoviae, M. meleagridis, M. iowae) and non-pathogenic species (M. gallinaceum, M. gallinarum, M. iners and M. pullorum). The authors successfully demonstrated the feasibility of inducing avian mycoplasmas to synthetize in vitro a biofilm, which can be visually quantified. The only species that did not produce any biofilm was M. iowae. In general, the pathogenic mycoplasmas produced greater quantities of biofilm compared to the non-pathogenic ones. Furthermore, it was observed that the ability to produce biofilm appeared to vary, both qualitatively and quantitatively, not only among different species but also among isolates of a single species. Future studies will be necessary to determine whether biofilm production plays a pivotal epidemiological role for the pathogenic avian mycoplasmas.}, }
@article {pmid38514634, year = {2024}, author = {Carreira de Paula, J and García Olmedo, P and Gómez-Moracho, T and Buendía-Abad, M and Higes, M and Martín-Hernández, R and Osuna, A and de Pablos, LM}, title = {Promastigote EPS secretion and haptomonad biofilm formation as evolutionary adaptations of trypanosomatid parasites for colonizing honeybee hosts.}, journal = {NPJ biofilms and microbiomes}, volume = {10}, number = {1}, pages = {27}, pmid = {38514634}, issn = {2055-5008}, mesh = {Humans ; Bees ; Animals ; *Parasites ; Ecosystem ; *Trypanosomatina/parasitology ; Biological Evolution ; }, abstract = {Bees are major pollinators involved in the maintenance of all terrestrial ecosystems. Biotic and abiotic factors placing these insects at risk is a research priority for ecological and agricultural sustainability. Parasites are one of the key players of this global decline and the study of their mechanisms of action is essential to control honeybee colony losses. Trypanosomatid parasites and particularly the Lotmaria passim are widely spread in honeybees, however their lifestyle is poorly understood. In this work, we show how these parasites are able to differentiate into a new parasitic lifestyle: the trypanosomatid biofilms. Using different microscopic techniques, we demonstrated that the secretion of Extracellular Polymeric Substances by free-swimming unicellular promastigote forms is a prerequisite for the generation and adherence of multicellular biofilms to solid surfaces in vitro and in vivo. Moreover, compared to human-infective trypanosomatid parasites our study shows how trypanosomatid parasites of honeybees increases their resistance and thus resilience to drastic changes in environmental conditions such as ultralow temperatures and hypoosmotic shock, which would explain their success thriving within or outside their hosts. These results set up the basis for the understanding of the success of this group of parasites in nature and to unveil the impact of such pathogens in honeybees, a keystones species in most terrestrial ecosystems.}, }
@article {pmid38512170, year = {2024}, author = {Pham, HN and Than, TDN and Nguyen, HA and Vu, DH and Phung, TH and Nguyen, TK}, title = {Antibiotic Resistance, Biofilm Formation, and Persistent Phenotype of Klebsiella pneumoniae in a Vietnamese Tertiary Hospital: A Focus on Amikacin.}, journal = {Microbial drug resistance (Larchmont, N.Y.)}, volume = {30}, number = {5}, pages = {203-209}, doi = {10.1089/mdr.2023.0267}, pmid = {38512170}, issn = {1931-8448}, mesh = {Humans ; *Amikacin/pharmacology ; *Anti-Bacterial Agents/pharmacology ; *Biofilms/drug effects ; *Drug Resistance, Multiple, Bacterial ; *Klebsiella Infections/drug therapy/microbiology ; *Klebsiella pneumoniae/drug effects ; Microbial Sensitivity Tests ; Phenotype ; Southeast Asian People ; Tertiary Care Centers ; Vietnam ; Intensive Care Units ; }, abstract = {Klebsiella pneumoniae stands out as a major opportunistic pathogen responsible for both hospital- and community-acquired bacterial infections. This study comprehensively assesses the antibiotic resistance, amikacin persistent patterns, and biofilm-forming ability of 247 isolates of K. pneumoniae obtained from an intensive care unit of a tertiary hospital in Vietnam. Microdilution assays, conducted on a 96-well plate, determined the minimum inhibitory concentrations (MICs) of amikacin. Susceptibility data for other antibiotics were gathered from the antibiogram profile. Stationary-phase bacteria were exposed to 50 × MIC, and viable bacteria counts were measured to determine amikacin persistence. Biofilm forming capacity on 96-well polystyrene surfaces was assessed by biomass and viable bacteria. The prevalence of resistance was notably high across most antibiotics, with 64.8% classified as carbapenem-resistant K. pneumoniae and 81.4% as multidrug resistant. Amikacin, however, exhibited a relatively low rate of resistance. Of the isolates, 58.2% demonstrated a moderate to strong biofilm formation capacity, and these were found to be poorly responsive to amikacin. K. pneumoniae reveals a significant inclination for amikacin persistence, with ∼45% of isolates displaying an antibiotic antibiotic-survival ratio exceeding 10%. The study sheds light on challenges in treating of K. pneumoniae infection in Vietnam, encompassing a high prevalence of antibiotic resistance, a substantial ability to form biofilm, and a notable rate of antibiotic persistence.}, }
@article {pmid38511958, year = {2024}, author = {Gager, C and Flores-Mireles, AL}, title = {Blunted blades: new CRISPR-derived technologies to dissect microbial multi-drug resistance and biofilm formation.}, journal = {mSphere}, volume = {9}, number = {4}, pages = {e0064223}, pmid = {38511958}, issn = {2379-5042}, support = {R01 DK128805/DK/NIDDK NIH HHS/United States ; }, abstract = {The spread of multi-drug-resistant (MDR) pathogens has rapidly outpaced the development of effective treatments. Diverse resistance mechanisms further limit the effectiveness of our best treatments, including multi-drug regimens and last line-of-defense antimicrobials. Biofilm formation is a powerful component of microbial pathogenesis, providing a scaffold for efficient colonization and shielding against anti-microbials, which further complicates drug resistance studies. Early genetic knockout tools didn't allow the study of essential genes, but clustered regularly interspaced palindromic repeat inference (CRISPRi) technologies have overcome this challenge via genetic silencing. These tools rapidly evolved to meet new demands and exploit native CRISPR systems. Modern tools range from the creation of massive CRISPRi libraries to tunable modulation of gene expression with CRISPR activation (CRISPRa). This review discusses the rapid expansion of CRISPRi/a-based technologies, their use in investigating MDR and biofilm formation, and how this drives further development of a potent tool to comprehensively examine multi-drug resistance.}, }
@article {pmid38511008, year = {2024}, author = {Goudot, S and Mathieu, L and Herbelin, P and Soreau, S and Jorand, FPA}, title = {Growth dynamic of biofilm-associated Naegleria fowleri in freshwater on various materials.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1369665}, pmid = {38511008}, issn = {1664-302X}, abstract = {In industrial water systems, the occurrence of biofilm-associated pathogenic free-living amoebae (FLA) such as Naegleria fowleri is a potential hygienic problem, and factors associated with its occurrence remain poorly understood. This study aimed to evaluate the impact of four cooling circuit materials on the growth of N. fowleri in a freshwater biofilm formed at 42°C and under a hydrodynamic shear rate of 17 s[-1] (laminar flow): polyvinyl chloride, stainless steel, brass, and titanium. Colonization of the freshwater biofilms by N. fowleri was found to be effective on polyvinyl chloride, stainless steel, and titanium. For these three materials, the ratio of (bacterial prey)/(amoeba) was found to control the growth of N. fowleri. All materials taken together, a maximum specific growth rate of 0.18 ± 0.07 h[-1] was associated with a generation time of ~4 h. In contrast, no significant colonization of N. fowleri was found on brass. Therefore, the contribution of copper is strongly suspected.}, }
@article {pmid38510214, year = {2024}, author = {Kadirvelu, L and Sivaramalingam, SS and Jothivel, D and Chithiraiselvan, DD and Karaiyagowder Govindarajan, D and Kandaswamy, K}, title = {A review on antimicrobial strategies in mitigating biofilm-associated infections on medical implants.}, journal = {Current research in microbial sciences}, volume = {6}, number = {}, pages = {100231}, pmid = {38510214}, issn = {2666-5174}, abstract = {Biomedical implants are crucial in providing support and functionality to patients with missing or defective body parts. However, implants carry an inherent risk of bacterial infections that are biofilm-associated and lead to significant complications. These infections often result in implant failure, requiring replacement by surgical restoration. Given these complications, it is crucial to study the biofilm formation mechanism on various biomedical implants that will help prevent implant failures. Therefore, this comprehensive review explores various types of implants (e.g., dental implant, orthopedic implant, tracheal stent, breast implant, central venous catheter, cochlear implant, urinary catheter, intraocular lens, and heart valve) and medical devices (hemodialyzer and pacemaker) in use. In addition, the mechanism of biofilm formation on those implants, and their pathogenesis were discussed. Furthermore, this article critically reviews various approaches in combating implant-associated infections, with a special emphasis on novel non-antibiotic alternatives to mitigate biofilm infections.}, }
@article {pmid38509138, year = {2024}, author = {Karačić, S and Palmer, B and Gee, CT and Bierbaum, G}, title = {Oxygen-dependent biofilm dynamics in leaf decay: an in vitro analysis.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {6728}, pmid = {38509138}, issn = {2045-2322}, support = {348043586//Deutsche Forschungsgemeinschaft/ ; }, mesh = {RNA, Ribosomal, 16S/genetics ; *Biofilms ; *Bacteria/genetics ; Prokaryotic Cells ; Plant Leaves ; }, abstract = {Biofilms are important in the natural process of plant tissue degradation. However, fundamental knowledge of biofilm community structure and succession on decaying leaves under different oxygen conditions is limited. Here, we used 16S rRNA and ITS gene amplicon sequencing to investigate the composition, temporal dynamics, and community assembly processes of bacterial and fungal biofilms on decaying leaves in vitro. Leaves harvested from three plant species were immersed in lake water under aerobic and anaerobic conditions in vitro for three weeks. Biofilm-covered leaf samples were collected weekly and investigated by scanning electron microscopy. The results showed that community composition differed significantly between biofilm samples under aerobic and anaerobic conditions, though not among plant species. Over three weeks, a clear compositional shift of the bacterial and fungal biofilm communities was observed. The alpha diversity of prokaryotes increased over time in aerobic assays and decreased under anaerobic conditions. Oxygen availability and incubation time were found to be primary factors influencing the microbial diversity of biofilms on different decaying plant species in vitro. Null models suggest that stochastic processes governed the assembly of biofilm communities of decaying leaves in vitro in the early stages of biofilm formation and were further shaped by niche-associated factors.}, }
@article {pmid38508759, year = {2024}, author = {Hamada, S and Minami, S and Gomi, M}, title = {Heparinoid enhances the efficacy of a bactericidal agent by preventing Cutibacterium acnes biofilm formation via quorum sensing inhibition.}, journal = {Journal of microorganism control}, volume = {29}, number = {1}, pages = {27-31}, doi = {10.4265/jmc.29.1_27}, pmid = {38508759}, issn = {2758-6391}, mesh = {Humans ; Quorum Sensing ; *Heparinoids/pharmacology ; Biofilms ; Anti-Bacterial Agents/pharmacology ; *Acne Vulgaris/drug therapy ; Homoserine/*analogs &amp; derivatives ; *Lactones ; }, abstract = {Cutibacterium acnes is an opportunistic pathogen in acne vulgaris. C. acnes produces autoinducer-2 (AI-2）, a signaling molecule used for communication known as quorum sensing (QS）. In C. acnes, QS reportedly upregulates biofilm formation leading to resistance against bactericidal agents. In this study, we analyzed how heparinoid affected QS and biofilm formation of the opportunistic pathogen C. acnes. We also verified whether heparinoid would suppress biofilm formation and enhance the efficacy of the bactericidal agent 4-isopropyl-3-methylphenol (IPMP) against C. acnes biofilms. We ran an AI-2 bioassay using Vibrio harveyi ATCC BBA-1121. Heparinoid exhibited inhibitory activity against AI-2 at concentrations of 0.003-0.005%, suggesting an AI-2 analog-derived or C. acnes culture supernatant-derived inhibition of the AI-2 activity. To evaluate how heparinoid suppresses biofilm formation in C. acnes, we completed a biofilm assay in 96-well plates. We also evaluated the bactericidal activity of IPMP against the C. acnes biofilm prepared with or without heparinoid. Heparinoid inhibited C. acnes biofilm formation and IPMP bactericidal efficacy increased upon heparinoid-mediated suppression of biofilm formation. In this study, we clarified that heparinoid inhibits the AI-2-mediated QS of C. acnes, thereby suppressing biofilm formation and increasing IPMP bactericidal efficacy, potentially suppressing acne vulgaris.}, }
@article {pmid38507111, year = {2024}, author = {Choi, CH and Mun, S and Oh, MH}, title = {Identification and characterization of Acinetobacter nosocomialis BfmRS, two-component regulatory system, essential for biofilm development.}, journal = {Genes &amp; genomics}, volume = {46}, number = {5}, pages = {531-539}, pmid = {38507111}, issn = {2092-9293}, support = {R202100704//Dankook University/ ; }, mesh = {Humans ; *Acinetobacter/genetics ; Biofilms ; Mutation ; }, abstract = {BACKGROUND: Biofilm development by bacteria is considered to be an essential stage in the bacterial infection. Acinetobacter nosocomialis is an important nosocomial pathogen causing a variety of human infections. However, characteristics and specific determinants of biofilm development have been poorly characterized in A. nosocomialis.<br><br>OBJECTIVE: The aim of this study was to investigate the factors involved in the biofilm development by A. nosocomialis.<br><br>METHODS: Library of random transposon mutants was constructed using the Tn5 mutagenesis. The mutant strains, in which the ability of biofilm formation was significantly impaired, were screened by gentian violet staining. The roles of BfmR and BfmS were determined by constructing a bfmR and bfmS deletion mutant and analyzing the effects of bfmR and bfmS mutation on the biofilm development and motility of A. nosocomialis.<br><br>RESULTS: We identified a biofilm-defective mutant in which a transposon insertion inactivated an open reading frame encoding the BfmR in a two-component regulatory system consisting of BfmR and BfmS. The bfmR mutant revealed a significant reduction in biofilm formation and motility compared to wild-type strain. Deficiency in the biofilm formation and motility of the bfmR mutant was restored by single copy bfmR complementation. In contrast, the bfmS mutant had no effect on biofilm formation.<br><br>CONCLUSION: A. nosocomialis has a two-component regulatory system, BfmRS. BfmR is a response regulator required for the initial attachment and maturation of biofilm during the biofilm development as well as the bacterial growth. BfmR could be a potential drug target for A. nosocomialis infection.}, }
@article {pmid38506718, year = {2024}, author = {Jha, NK and Gopu, V and Sivasankar, C and Singh, SR and Devi, PB and Murali, A and Shetty, PH}, title = {In vitro and in silico assessment of anti-biofilm and anti-quorum sensing properties of 2,4-Di-tert butylphenol against Acinetobacter baumannii.}, journal = {Journal of medical microbiology}, volume = {73}, number = {3}, pages = {}, doi = {10.1099/jmm.0.001813}, pmid = {38506718}, issn = {1473-5644}, mesh = {*Acinetobacter baumannii ; Biofilms ; Phenols/pharmacology ; Anti-Bacterial Agents/pharmacology ; *Salts ; }, abstract = {Introduction. Acinetobacter baumannii is a nosocomial pathogen with a high potential to cause food-borne infections. It is designated as a critical pathogen by the World Health Organization due to its multi-drug resistance and mortalities reported. Biofilm governs major virulence factors, which promotes drug resistance in A. baumannii. Thus, a compound with minimum selection pressure on the pathogen can be helpful to breach biofilm-related virulence.Hypothesis/Gap Statement. To identify anti-biofilm and anti-virulent metabolites from extracts of wild Mangifera indica (mango) brine pickle bacteria that diminishes pathogenesis and resistance of A. baumannii.Aim. This study reports anti-biofilm and anti-quorum sensing (QS) efficacy of secondary metabolites from bacterial isolates of fermented food origin.Method. Cell-free supernatants (CFS) of 13 bacterial isolates from fermented mango brine pickles were screened for their efficiency in inhibiting biofilm formation and GC-MS was used to identify its metabolites. Anti-biofilm metabolite was tested on early and mature biofilms, pellicle formation, extra polymeric substances (EPS), cellular adherence, motility and resistance of A. baumannii. Gene expression and in silico studies were also carried out to validate the compounds efficacy.Results. CFS of TMP6b identified as Bacillus vallismortis, inhibited biofilm production (83.02 %). Of these, major compound was identified as 2,4-Di-tert-butyl phenol (2,4-DBP). At sub-lethal concentrations, 2,4-DBP disrupted both early and mature biofilm formation. Treatment with 2,4-DBP destructed in situ biofilm formed on glass and plastic. In addition, key virulence traits like pellicle (77.5 %), surfactant (95.3 %), EPS production (3-fold) and cell adherence (65.55 %) reduced significantly. A. baumannii cells treated with 2,4-DBP showed enhanced sensitivity towards antibiotics, oxide radicals and blood cells. Expression of biofilm-concomitant virulence genes like csuA/B, pgaC, pgaA, bap, bfmR, katE and ompA along with QS genes abaI, abaR significantly decreased. The in silico studies further validated the higher binding affinity of 2,4-DBP to the AbaR protein than the cognate ligand molecule.Conclusion. To our knowledge, this is the first report to demonstrate 2,4- DBP has anti-pathogenic potential alone and with antibiotics by in vitro, and in silico studies against A. baumannii. It also indicates its potential use in therapeutics and bio-preservatives.}, }
@article {pmid38505856, year = {2024}, author = {Canale, V and Skiba-Kurek, I and Klesiewicz, K and Papież, M and Ropek, M and Pomierny, B and Piska, K and Koczurkiewicz-Adamczyk, P and Empel, J and Karczewska, E and Zajdel, P}, title = {Improving Activity of New Arylurea Agents against Multidrug-Resistant and Biofilm-Producing Staphylococcus epidermidis.}, journal = {ACS medicinal chemistry letters}, volume = {15}, number = {3}, pages = {369-375}, pmid = {38505856}, issn = {1948-5875}, abstract = {Multidrug-resistant (MDR) strains of Staphylococcus epidermidis (S. epidermidis), prevalent in hospital environments, contribute to increased morbidity and mortality, especially among newborns, posing a critical concern for neonatal sepsis. In response to the pressing demand for novel antibacterial therapies, we present findings from synthetic chemistry and structure-activity relationship studies focused on arylsulfonamide/arylurea derivatives of aryloxy[1-(thien-2-yl)propyl]piperidines. Through bioisosteric replacement of the sulfonamide fragment with a urea moiety, compound 25 was identified, demonstrating potent bacteriostatic activity against clinical multidrug-resistant S. epidermidis strains (MIC50 and MIC90 = 1.6 and 3.125 μg/mL). Importantly, it showed activity against linezolid-resistant strains and exhibited selectivity over mammalian cells. Compound 25 displayed antibiofilm-forming properties against clinical S. epidermidis strains and demonstrated the capacity to eliminate existing biofilm layers. Additionally, it induced complete depolarization of the bacterial membrane in clinical S. epidermidis strains. In light of these findings, targeting bacterial cell membranes with compound 25 emerges as a promising strategy in the fight against multidrug-resistant S. epidermidis strains.}, }
@article {pmid38505565, year = {2024}, author = {Wang, L and Chen, QW and Qin, YC and Yi, XL and Zeng, H}, title = {Analysis of carbapenem-resistant Acinetobacter baumannii carbapenemase gene distribution and biofilm formation.}, journal = {International journal of molecular epidemiology and genetics}, volume = {15}, number = {1}, pages = {1-11}, pmid = {38505565}, issn = {1948-1756}, abstract = {OBJECTIVE: In recent years, Acinetobacter baumannii has been appearing in hospitals with high drug resistance and strong vitality, which brings many difficulties to clinical treatment. In this study, 255 strains of A. baumannii were isolated from Youjiang Medical University for Nationalities Affiliated Hospital clinical samples and found to be highly resistant to carbapenems. The drug resistance, biofilm-forming ability, and carbapenase gene distribution of 145 carbapenem-resistant A. baumannii (CRAB) strains were analyzed statistically.<br><br>METHODS: The clinically isolated strains were detected using Vitek mass spectrometry and Vitek2-compact for bacterial identification and susceptibility testing, respectively. The biofilms of clinical isolates were quantitatively detected by microplate crystal violet staining, and qualitatively observed by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). And the common carbapenemase genes were detected by polymerase chain reaction (PCR).<br><br>RESULTS: The 255 clinical isolates from the Youjiang District of western Guangxi Province had a high resistance rate to carbapenems antibiotics. The main specimens were from the intensive care unit (49%), and the most important specimens were sputum specimens (80%). All 145 strains of CRAB produced different degrees of biofilm, and six carbapenenase genes were detected. We found that there were significant differences in biofilm formation between resistant and sensitive strains of tobramycin, levofloxacin, ciprofloxacin, tigecycline, and doxycycline (P<0.05). The distribution of blaOXA-23 and blaOXA51 genes was significantly different from CRAB biofilm formation (P<0.05). In addition, AmpC, blaOXA-23, blaOXA-51, and TEM genes were more distributed in antibiotic-resistant strains.<br><br>CONCLUSION: The clinical strains have a high resistance rate to carbapenems, and the CRAB with blaOXA-51 and blaOXA-23 genes has a high resistance to antibiotics and a strong biofilm.}, }
@article {pmid38505547, year = {2024}, author = {Wallart, L and Ben Mlouka, MA and Saffiedine, B and Coquet, L and Le, H and Hardouin, J and Jouenne, T and Phan, G and Kiefer-Meyer, MC and Girard, E and Broutin, I and Cosette, P}, title = {BacA: a possible regulator that contributes to the biofilm formation of Pseudomonas aeruginosa.}, journal = {Frontiers in microbiology}, volume = {15}, number = {}, pages = {1332448}, pmid = {38505547}, issn = {1664-302X}, abstract = {Previously, we pointed out in P. aeruginosa PAO1 biofilm cells the accumulation of a hypothetical protein named PA3731 and showed that the deletion of the corresponding gene impacted its biofilm formation capacity. PA3731 belongs to a cluster of 4 genes (pa3732 to pa3729) that we named bac for "Biofilm Associated Cluster." The present study focuses on the PA14_16140 protein, i.e., the PA3732 (BacA) homolog in the PA14 strain. The role of BacA in rhamnolipid secretion, biofilm formation and virulence, was confirmed by phenotypic experiments with a bacA mutant. Additional investigations allow to advance that the bac system involves in fact 6 genes organized in operon, i.e., bacA to bacF. At a molecular level, quantitative proteomic studies revealed an accumulation of the BAC cognate partners by the bacA sessile mutant, suggesting a negative control of BacA toward the bac operon. Finally, a first crystallographic structure of BacA was obtained revealing a structure homologous to chaperones or/and regulatory proteins.}, }
@article {pmid38502922, year = {2024}, author = {Zhang, L and Graham, N and Li, G and Zhu, Y and Yu, W}, title = {Excessive Ozonation Stress Triggers Severe Membrane Biofilm Accumulation and Fouling.}, journal = {Environmental science &amp; technology}, volume = {58}, number = {13}, pages = {5899-5910}, doi = {10.1021/acs.est.3c10429}, pmid = {38502922}, issn = {1520-5851}, mesh = {Membranes, Artificial ; Ultrafiltration ; *Ozone ; *Water Purification ; Biofilms ; }, abstract = {The established benefits of ozone on microbial pathogen inactivation, natural organic matter degradation, and inorganic/organic contaminant oxidation have favored its application in drinking water treatment. However, viable bacteria are still present after the ozonation of raw water, bringing a potential risk to membrane filtration systems in terms of biofilm accumulation and fouling. In this study, we shed light on the role of the specific ozone dose (0.5 mg-O3/mg-C) in biofilm accumulation during long-term membrane ultrafiltration. Results demonstrated that ozonation transformed the molecular structure of influent dissolved organic matter (DOM), producing fractions that were highly bioavailable at a specific ozone dose of 0.5, which was inferred to be a turning point. With the increase of the specific ozone dose, the biofilm microbial consortium was substantially shifted, demonstrating a decrease in richness and diversity. Unexpectedly, the opportunistic pathogen Legionella was stimulated and occurred in approximately 40% relative abundance at the higher specific ozone dose of 1. Accordingly, the membrane filtration system with a specific ozone dose of 0.5 presented a lower biofilm thickness, a weaker fluorescence intensity, smaller concentrations of polysaccharides and proteins, and a lower Raman activity, leading to a lower hydraulic resistance, compared to that with a specific ozone dose of 1. Our findings highlight the interaction mechanism between molecular-level DOM composition, biofilm microbial consortium, and membrane filtration performance, which provides an in-depth understanding of the impact of ozonation on biofilm accumulation.}, }
@article {pmid38501832, year = {2024}, author = {Pan, S and Underhill, SAM and Hamm, CW and Stover, MA and Butler, DR and Shults, CA and Manjarrez, JR and Cabeen, MT}, title = {Glycerol metabolism impacts biofilm phenotypes and virulence in Pseudomonas aeruginosa via the Entner-Doudoroff pathway.}, journal = {mSphere}, volume = {9}, number = {4}, pages = {e0078623}, pmid = {38501832}, issn = {2379-5042}, support = {R35 GM138018/GM/NIGMS NIH HHS/United States ; }, abstract = {Pseudomonas aeruginosa is a ubiquitous bacterium and a notorious opportunistic pathogen that forms biofilm structures in response to many environmental cues. Biofilm formation includes attachment to surfaces and the production of the exopolysaccharide Pel, which is present in both the PAO1 and PA14 laboratory strains of P. aeruginosa. Biofilms help protect bacterial cells from host defenses and antibiotics and abet infection. The carbon source used by the cells also influences biofilm, but these effects have not been deeply studied. We show here that glycerol, which can be liberated from host surfactants during infection, encourages surface attachment and magnifies colony morphology differences. We find that glycerol kinase is important but not essential for glycerol utilization and relatively unimportant for biofilm behaviors. Among downstream enzymes predicted to take part in glycerol utilization, Edd stood out as being important for glycerol utilization and for enhanced biofilm phenotypes in the presence of glycerol. Thus, gluconeogenesis and catabolism of anabolically produced glucose appear to impact not only the utilization of glycerol but also glycerol-stimulated biofilm phenotypes. Finally, waxworm moth larvae and nematode infection models reveal that interruption of the Entner-Doudoroff pathway, but not abrogation of glycerol phosphorylation, unexpectedly increases P. aeruginosa lethality in both acute and chronic infections, even while stimulating a stronger immune response by Caenorhabditis elegans.IMPORTANCEPseudomonas aeruginosa, the ubiquitous environmental bacterium and human pathogen, forms multicellular communities known as biofilms in response to various stimuli. We find that glycerol, a common carbon source that bacteria can use for energy and biosynthesis, encourages biofilm behaviors such as surface attachment and colony wrinkling by P. aeruginosa. Glycerol can be derived from surfactants that are present in the human lungs, a common infection site. Glycerol-stimulated biofilm phenotypes do not depend on phosphorylation of glycerol but are surprisingly impacted by a glucose breakdown pathway, suggesting that it is glycerol utilization, and not its mere presence or cellular import, that stimulates biofilm phenotypes. Moreover, the same mutations that block glycerol-stimulated biofilm phenotypes also impact P. aeruginosa virulence in both acute and chronic animal models. Notably, a glucose-breakdown mutant (Δedd) counteracts biofilm phenotypes but shows enhanced virulence and stimulates a stronger immune response in Caenorhabditis elegans.}, }
@article {pmid38499092, year = {2024}, author = {Wang, Y and Zhao, X and Zhou, X and Dai, J and Hu, X and Piao, Y and Zu, G and Xiao, J and Shi, K and Liu, Y and Li, Y and Shi, L}, title = {A supramolecular hydrogel dressing with antibacterial, immunoregulation, and pro-regeneration ability for biofilm-associated wound healing.}, journal = {Journal of controlled release : official journal of the Controlled Release Society}, volume = {368}, number = {}, pages = {740-755}, doi = {10.1016/j.jconrel.2024.03.024}, pmid = {38499092}, issn = {1873-4995}, mesh = {Humans ; *Hydrogels ; Polyethyleneimine ; Bandages ; Anti-Bacterial Agents/pharmacology ; Biofilms ; *Deafness ; }, abstract = {Chronic wound treatment has emerged as a significant healthcare concern worldwide due to its substantial economic burden and the limited effectiveness of current treatments. Effective management of biofilm infections, regulation of excessive oxidative stress, and promotion of tissue regeneration are crucial for addressing chronic wounds. Hydrogel stands out as a promising candidate for chronic wound treatment. However, its clinical application is hindered by the difficulty in designing and fabricating easily and conveniently. To overcome these obstacles, we present a supermolecular G-quadruplex hydrogel with the desired multifunction via a dynamic covalent strategy and Hoogsteen-type hydrogen bonding. The G-quadruplex hydrogel is made from the self-assembly of guanosine, 2-formylphenyboronic acid, polyethylenimine, and potassium chloride, employing dynamic covalent strategy and Hoogsteen-type hydrogen bonding. In the acidic/oxidative microenvironment associated with bacterial infections, the hydrogel undergoes controlled degradation, releasing the polyethylenimine domain, which effectively eliminates bacteria. Furthermore, nanocomplexes comprising guanosine monophosphate and manganese sulfate are incorporated into the hydrogel skeleton, endowing it with the ability to scavenge reactive oxygen species and modulate macrophages. Additionally, the integration of basic fibroblast growth factor into the G-quadruplex skeleton through dynamic covalent bonds facilitates controlled tissue regeneration. In summary, the facile preparation process and the incorporation of multiple functionalities render the G-quadruplex hydrogel a highly promising candidate for advanced wound dressing. It holds great potential to transition from laboratory research to clinical practice, addressing the pressing needs of chronic wound management.}, }
@article {pmid38498718, year = {2024}, author = {Karbelkar, AA and Font, M and Smith, TJ and Sondermann, H and O'Toole, GA}, title = {Reconstitution of a biofilm adhesin system from a sulfate-reducing bacterium in Pseudomonas fluorescens.}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, volume = {121}, number = {13}, pages = {e2320410121}, pmid = {38498718}, issn = {1091-6490}, support = {P20 GM113132/GM/NIGMS NIH HHS/United States ; R01 AI083256/AI/NIAID NIH HHS/United States ; R01 AI168017/AI/NIAID NIH HHS/United States ; R01 GM123609/GM/NIGMS NIH HHS/United States ; }, mesh = {*Pseudomonas fluorescens/genetics/metabolism ; Sulfates/metabolism ; Adhesins, Bacterial/genetics/metabolism ; Biofilms ; Carrier Proteins/metabolism ; Cyclic GMP/metabolism ; Bacterial Proteins/genetics/metabolism ; Gene Expression Regulation, Bacterial ; }, abstract = {Biofilms of sulfate-reducing bacterium (SRB) like Desulfovibrio vulgaris Hildenborough (DvH) can facilitate metal corrosion in various industrial and environmental settings leading to substantial economic losses. Although the mechanisms of biofilm formation by DvH are not yet well understood, recent studies indicate the large adhesin, DvhA, is a key determinant of biofilm formation. The dvhA gene neighborhood resembles the biofilm-regulating Lap system of Pseudomonas fluorescens but is curiously missing the c-di-GMP-binding regulator LapD. Instead, DvH encodes an evolutionarily unrelated c-di-GMP-binding protein (DVU1020) that we hypothesized is functionally analogous to LapD. To study this unusual Lap system and overcome experimental limitations with the slow-growing anaerobe DvH, we reconstituted its predicted SRB Lap system in a P. fluorescens strain lacking its native Lap regulatory components (ΔlapGΔlapD). Our data support the model that DvhA is a cell surface-associated LapA-like adhesin with a N-terminal "retention module" and that DvhA is released from the cell surface upon cleavage by the LapG-like protease DvhG. Further, we demonstrate DVU1020 (named here DvhD) represents a distinct class of c-di-GMP-binding, biofilm-regulating proteins that regulates DvhG activity in response to intracellular levels of this second messenger. This study provides insight into the key players responsible for biofilm formation by DvH, thereby expanding our understanding of Lap-like systems.}, }
@article {pmid38497440, year = {2024}, author = {Matoso, FB and Montagner, F and Grecca, FS and Rampelotto, PH and Kopper, PMP}, title = {Microbial composition and diversity in intraradicular biofilm formed in situ: New concepts based on next-generation sequencing.}, journal = {Molecular oral microbiology}, volume = {39}, number = {5}, pages = {368-380}, doi = {10.1111/omi.12462}, pmid = {38497440}, issn = {2041-1014}, mesh = {*Biofilms/growth &amp; development ; Humans ; *High-Throughput Nucleotide Sequencing ; *Bacteria/classification/genetics ; *RNA, Ribosomal, 16S/genetics ; *Microbiota ; *Dental Pulp Cavity/microbiology ; Adult ; DNA, Bacterial/analysis ; Male ; Molar/microbiology ; Tooth Root/microbiology ; Female ; Young Adult ; }, abstract = {This study aimed to characterize the taxonomic composition of intraradicular multispecies biofilms (IMBs) formed in situ in a model to reproduce clinical conditions. Twelve palatal roots of maxillary molars had its canals prepared. Two roots were randomly selected to sterility control. Ten intraoral prosthetic appliances with lateral slots were fabricated. The roots were positioned in the slots with the canal access open to the oral cavity. Eight volunteers wore the appliance for 21 days, and two wore it at two different time points. One root from each appliance was removed and stored at -20°C until DNA extraction and sequencing (n = 10). Biofilm was analyzed using next-generation sequencing and bioinformatics. The V4 hyper-variable region of the 16SrRNA gene was amplified and sequenced. For data analyses, the mothur pipeline was used for 16SrRNA processing, and subsequent analyses of the sequence dataset were performed in R using the MicrobiomeAnalyst R package. The taxonomy-based analysis of bacterial communities identified 562 operational taxonomic units (OTUs), which belonged to 93 genera, 44 families, and 8 phyla. Bacterial colonization was different for each biofilm, and samples did not have the same group of bacteria. Alpha and beta diversity analysis revealed some general patterns of sample clustering. A core microbiome of prevalent OTUs and genera was identified. IMBs were heterogeneous when analyzed individually, but some diversity patterns were found after sample clustering. The experimental model seemed to reproduce the actual biofilm composition in endodontic infections, which suggests that it may be used to evaluate disinfection protocols.}, }
@article {pmid38496814, year = {2024}, author = {Ibrahim, GI and Jawad, HA}, title = {Eradication of mature biofilm from the isthmus region using Er, Cr: YSGG Laser as an activator of 2% chlorhexidine gluconate.}, journal = {Journal of clinical and experimental dentistry}, volume = {16}, number = {2}, pages = {e159-e165}, pmid = {38496814}, issn = {1989-5488}, abstract = {BACKGROUND: Challenges in the root canal system, such as isthmus, may limit the action of endodontic equipment and irrigation solutions, so using laser agitation is recommended to upgrade the removal of microbial biofilm. The objective of this study is to assess the effectiveness of the laser in photon-induced photoacoustic streaming protocol agitation of 2% chlorohexidine gluconate in removing mature biofilm in complex root canal systems.<br><br>MATERIAL AND METHODS: Seventy-five mesial roots of the lower first and second molars were separated and cultivated with Enterococcus faecalis bacteria for 30 days (except for the negative control group samples). The samples were divided into four groups (n=15), one group acted as a positive control, other groups were irrigated with 2% chlorohexidine gluconate, some of them were agitated with a passive ultrasonic device, while the other samples were agitated by an Erbium, chromium-doped yttrium, scandium, gallium, and garnet laser in photon-induced photoacoustic streaming protocol. An atomic force microscope was used as a new method to get the results in the isthmus area; A scanning electron microscope was also used in the study to examine the samples before and after the treatment. Statistical Package for Social Sciences software was used to collect and analyze data, and two-way ANOVA was used to compare the means of the test groups.<br><br>RESULTS: According to the atomic force microscope and scanning electron microscope analyses, Erbium laser and passive ultrasonic activation groups showed higher antimicrobial efficacy than the syringe irrigation group (p<0.05).<br><br>CONCLUSIONS: According to the study's results, the agitation of chlorohexidine gluconate fluid by Erbium laser in photon-induced photoacoustic streaming at 0.75 W offers better Enterococcus faecalis biofilm removal in the difficult-to-reach areas of lower first and second molars. Key words:Atomic force microscope, 2% chlorhexidine gluconate, Enterococcus faecalis, Erbium, chromium-doped yttrium, scandium, gallium, garnet laser, passive ultrasonic.}, }
@article {pmid38495771, year = {2024}, author = {Alidokht, L and Fitzpatrick, K and Butler, C and Hunsucker, KZ and Braga, C and Maza, WA and Fears, KP and Arekhi, M and Lanzarini-Lopes, M}, title = {UV emitting glass: A promising strategy for biofilm inhibition on transparent surfaces.}, journal = {Biofilm}, volume = {7}, number = {}, pages = {100186}, pmid = {38495771}, issn = {2590-2075}, abstract = {Marine biofouling causes serious environmental problems and has adverse impacts on the maritime industry. Biofouling on windows and optical equipment reduces surface transparency, limiting their application for on-site monitoring or continuous measurement. This work illustrates that UV emitting glasses (UEGs) can prevent the establishment and growth of biofilm on the illuminated surfaces. Specifically, this paper describes how UEGs are enabled by innovatively modifying the surfaces of the glass with light scattering particles. Modification of glass surface with silica nanoparticles at a concentration 26.5 μg/cm[2] resulted in over ten-fold increase in UV irradiance, while maintaining satisfactory visible and IR transparency metrics of over 99 %. The UEG reduced visible biological growth by 98 % and resulted in a decrease of 1.79 log in detected colony forming units when compared to the control during a 20 day submersion at Port Canaveral, Florida, United States. These findings serve as strong evidence that UV emitting glass should be explored as a promising approach for biofilm inhibition on transparent surfaces.}, }
@article {pmid38495770, year = {2024}, author = {Tian, S and Shi, L and Ren, Y and van der Mei, HC and Busscher, HJ}, title = {A normalized parameter for comparison of biofilm dispersants in vitro.}, journal = {Biofilm}, volume = {7}, number = {}, pages = {100188}, pmid = {38495770}, issn = {2590-2075}, abstract = {Dispersal of infectious biofilms increases bacterial concentrations in blood. To prevent sepsis, the strength of a dispersant should be limited to allow the immune system to remove dispersed bacteria from blood, preferably without antibiotic administration. Biofilm bacteria are held together by extracellular polymeric substances that can be degraded by dispersants. Currently, comparison of the strength of dispersants is not possible by lack of a suitable comparison parameter. Here, a biofilm dispersal parameter is proposed that accounts for differences in initial biofilm properties, dispersant concentration and exposure time by using PBS as a control and normalizing outcomes with respect to concentration and time. The parameter yielded near-identical values based on dispersant-induced reductions in biomass or biofilm colony-forming-units and appeared strain-dependent across pathogens. The parameter as proposed is largely independent of experimental methods and conditions and suitable for comparing different dispersants with respect to different causative strains in particular types of infection.}, }
@article {pmid38495170, year = {2024}, author = {Khanna, N and Girija A S, S and Priyadharsini J, V}, title = {Detection of the early putative biofilm marker pgaB among the MDR strains of A.baumannii.}, journal = {Heliyon}, volume = {10}, number = {5}, pages = {e27020}, pmid = {38495170}, issn = {2405-8440}, abstract = {BACKGROUND: pgaB associated biofilm formation in Acinetobacter baumannii enhances the virulence in concert with the high propensity of drug resistance. This research is thus aimed to characterize the pgaB gene molecularly and to examine its co-occurrence with MDR.<br><br>METHODOLOGY: MDR strains of A. baumannii (N&#xa0;=&#xa0;73) were selected to detect the formation of biofilms. Genomic DNA was extracted further and screened for pgaB followed by amplicon sequencing from the representative strains. Frequency of its distribution in different groups of drug resistant strains at a significant p-value of <0.05 was further checked.<br><br>RESULTS: The biofilm assay showed high, low and negative biofilm formers in 58.9%, 31.5% and 0.9% of the strains respectively. The pgaB gene was detected in 14 strains of MDR A. baumannii (19.17%). Co-occurrence of pgaB gene was seen in all the strains that showed resistance to &#x3b2;-lactam inhibitors, cephems, carbapenems, fluoroquinolones and folates followed by 96% for the aminoglycosides and 25% in the efflux pump groups.<br><br>CONCLUSION: The study findings showed the occurrence of biofilms associated with pgaB in MDR A. baumannii strains. The results also suggest to track its role in varying the pattern of drug resistance with further experimentation.}, }
@article {pmid38494241, year = {2024}, author = {Liu, Y and Li, R and Zhang, Y and Jiao, S and Xu, T and Zhou, Y and Wang, Y and Wei, J and Du, W and Fujita, M and Du, Y and Wang, ZA}, title = {Unveiling the inverse antimicrobial impact of a hetero-chitooligosaccharide on Candida tropicalis growth and biofilm formation.}, journal = {Carbohydrate polymers}, volume = {333}, number = {}, pages = {121999}, doi = {10.1016/j.carbpol.2024.121999}, pmid = {38494241}, issn = {1879-1344}, mesh = {Animals ; Mice ; Candida tropicalis ; *Chitosan/pharmacology/chemistry ; *Anti-Infective Agents ; Antifungal Agents/pharmacology ; Biofilms ; *Oligosaccharides ; }, abstract = {Chitosan and chitooligosaccharide (COS) are renowned for their potent antimicrobial prowess, yet the precise antimicrobial efficacy of COS remains elusive due to scant structural information about the utilized saccharides. This study delves into the antimicrobial potential of COS, spotlighting a distinct hetero-chitooligosaccharide dubbed DACOS. In contrast to other COS, DACOS remarkably fosters the growth of Candida tropicalis planktonic cells and fungal biofilms. Employing gradient alcohol precipitation, DACOS was fractionated, unveiling diverse structural characteristics and differential impacts on C. tropicalis. Notably, in a murine model of systemic candidiasis, DACOS, particularly its 70 % alcohol precipitates, manifests a promotive effect on Candida infection. This research unveils a new pathway for exploring the intricate nexus between the structural attributes of chitosan oligosaccharides and their physiological repercussions, underscoring the imperative of crafting chitosan and COS with meticulously defined structural configurations.}, }
@article {pmid38494090, year = {2024}, author = {Cakin, I and Morrissey, B and Gordon, M and Gaffney, PPJ and Marcello, L and Macgregor, K and Taggart, MA}, title = {Comparing DNA isolation and sequencing strategies for 16S rRNA gene amplicon analysis in biofilm containing environments.}, journal = {Journal of microbiological methods}, volume = {220}, number = {}, pages = {106921}, doi = {10.1016/j.mimet.2024.106921}, pmid = {38494090}, issn = {1872-8359}, mesh = {RNA, Ribosomal, 16S/genetics ; Genes, rRNA ; *High-Throughput Nucleotide Sequencing/methods ; Sequence Analysis, DNA/methods ; *Databases, Nucleic Acid ; Bacteria/genetics ; }, abstract = {Bacteria are primarily responsible for biological water treatment processes in constructed wetland systems. Gravel in constructed wetlands serves as an essential substrate onto which complex bacterial biofilms may successfully grow and evolve. To fully understand the bacterial community in these systems it is crucial to properly isolate biofilms and process DNA from such substrates. This study looked at how best to isolate bacterial biofilms from gravel substrates in terms of bacterial richness. It considered factors including the duration of agitation during extraction, extraction temperature, and enzyme usage. Further, the 16S taxonomy data subsequently produced from Illumina MiSeq reads (using the SILVA 132 ribosomal RNA (rRNA) database on the DADA2 pipeline) were compared with the 16S data produced from Oxford Nanopore Technologies (ONT) MinION reads (using the NCBI 16S database on the EPI2ME pipeline). Finally, performance was tested by comparing the taxonomy data generated from the Illumina MiSeq and ONT MinION reads using the same (SILVA 132) database. We found no significant differences in the effective number of species observed when using different bacterial biofilm detachment techniques. However, enzyme treatment enhanced the total concentration of DNA. In terms of wetland community profiles, relative abundance differences within each sample type were clearer at the genus level. For genus-level taxonomic classification, MinION sequencing with the EPI2ME pipeline (NCBI database) produced bacterial abundance information that was poorly correlated with that from the Illumina MiSeq and DADA2 pipelines (SILVA132 database). When using the same database for each sequencing technology (SILVA132), the correlation between relative abundances at genus-level improved from negligible to moderate. This study provides detailed information of value to researchers working on constructed wetlands regarding efficient biofilm detachment techniques for DNA isolation and 16 s metabarcoding platforms for sequencing and data analysis.}, }
@article {pmid38818333, year = {2023}, author = {Liu, X and Jia, M and Wang, J and Cheng, H and Cai, Z and Yu, Z and Liu, Y and Ma, LZ and Zhang, L and Zhang, Y and Yang, L}, title = {Cell division factor ZapE regulates Pseudomonas aeruginosa biofilm formation by impacting the pqs quorum sensing system.}, journal = {mLife}, volume = {2}, number = {1}, pages = {28-42}, pmid = {38818333}, issn = {2770-100X}, abstract = {Pseudomonas aeruginosa is one of the leading nosocomial pathogens that causes both severe acute and chronic infections. The strong capacity of P. aeruginosa to form biofilms can dramatically increase its antibiotic resistance and lead to treatment failure. The biofilm resident bacterial cells display distinct gene expression profiles and phenotypes compared to their free-living counterparts. Elucidating the genetic determinants of biofilm formation is crucial for the development of antibiofilm drugs. In this study, a high-throughput transposon-insertion site sequencing (Tn-seq) approach was employed to identify novel P. aeruginosa biofilm genetic determinants. When analyzing the novel biofilm regulatory genes, we found that the cell division factor ZapE (PA4438) controls the P. aeruginosa pqs quorum sensing system. The ∆zapE mutant lost fitness against the wild-type PAO1 strain in biofilms and its production of 2-heptyl-3-hydroxy-4(1H)-quinolone (PQS) had been reduced. Further biochemical analysis showed that ZapE interacts with PqsH, which encodes the synthase that converts 2-heptyl-4-quinolone (HHQ) to PQS. In addition, site-directed mutagenesis of the ATPase active site of ZapE (K72A) abolished the positive regulation of ZapE on PQS signaling. As ZapE is highly conserved among the Pseudomonas group, our study suggests that it is a potential drug target for the control of Pseudomonas infections.}, }
@article {pmid38647577, year = {2022}, author = {Wang, D and Unsal, T and Kumseranee, S and Punpruk, S and Saleh, MA and Alotaibi, MD and Xu, D and Gu, T}, title = {Mitigation of carbon steel biocorrosion using a green biocide enhanced by a nature-mimicking anti-biofilm peptide in a flow loop.}, journal = {Bioresources and bioprocessing}, volume = {9}, number = {1}, pages = {67}, pmid = {38647577}, issn = {2197-4365}, abstract = {Biocorrosion, also called microbiologically influenced corrosion (MIC), is a common operational threat to many industrial processes. It threatens carbon steel, stainless steel and many other metals. In the bioprocessing industry, reactor vessels in biomass processing and bioleaching are prone to MIC. MIC is caused by biofilms. The formation and morphology of biofilms can be impacted by fluid flow. Fluid velocity affects biocide distribution and MIC. Thus, assessing the efficacy of a biocide for the mitigation of MIC under flow condition is desired before a field trial. In this work, a benchtop closed flow loop bioreactor design was used to investigate the biocide mitigation of MIC of C1018 carbon steel at 25 °C for 7 days using enriched artificial seawater. An oilfield biofilm consortium was analyzed using metagenomics. The biofilm consortium was grown anaerobically in the flow loop which had a holding vessel for the culture medium and a chamber to hold C1018 carbon steel coupons. Peptide A (codename) was a chemically synthesized cyclic 14-mer (cys-ser-val-pro-tyr-asp-tyr-asn-trp-tyr-ser-asn-trp-cys) with its core 12-mer sequence originated from a biofilm dispersing protein secreted by a sea anemone which possesses a biofilm-free exterior. It was used as a biocide enhancer. The combination of 50 ppm (w/w) THPS (tetrakis hydroxymethyl phosphonium sulfate) biocide + 100 nM (180 ppb by mass) Peptide A resulted in extra 1-log reduction in the sulfate reducing bacteria (SRB) sessile cell count and the acid producing bacteria (APB) sessile cell count compared to 50 ppm THPS alone treatment. Furthermore, with the enhancement of 100 nM Peptide A, extra 44% reduction in weight loss and 36% abatement in corrosion pit depth were achieved compared to 50 ppm THPS alone treatment.}, }
@article {pmid38652445, year = {2022}, author = {Heredia, MY and Andes, D}, title = {Correction to: Production and Isolation of the Candida Species Biofilm Extracellular Matrix.}, journal = {Methods in molecular biology (Clifton, N.J.)}, volume = {2542}, number = {}, pages = {C1}, doi = {10.1007/978-1-0716-2549-1_26}, pmid = {38652445}, issn = {1940-6029}, }
@article {pmid38650289, year = {2021}, author = {Ding, Q and Liu, Y and Hu, G and Guo, L and Gao, C and Chen, X and Chen, W and Chen, J and Liu, L}, title = {Engineering Escherichia coli biofilm to increase contact surface for shikimate and L-malate production.}, journal = {Bioresources and bioprocessing}, volume = {8}, number = {1}, pages = {118}, pmid = {38650289}, issn = {2197-4365}, support = {2020YFA0908300//National Key R &amp; D Program of China/ ; 32021005//Science Fund for Creative Research Groups of the National Natural Science Foundation of China/ ; BK20211529//Provincal Outstanding Youth Foundation of Jiangsu Province/ ; 21978113//the National Natural Science Foundation of China/ ; 22008087//the National Natural Science Foundation of China/ ; 22108099//National Natural Science Foundation of China/ ; }, abstract = {Microbial organelles are a promising model to promote cellular functions for the production of high-value chemicals. However, the concentrations of enzymes and nanoparticles are limited by the contact surface in single Escherichia coli cells. Herein, the definition of contact surface is to improve the amylase and CdS nanoparticles concentration for enhancing the substrate starch and cofactor NADH utilization. In this study, two biofilm-based strategies were developed to improve the contact surface for the production of shikimate and L-malate. First, the contact surface of E. coli was improved by amylase self-assembly with a blue light-inducible biofilm-based SpyTag/SpyCatcher system. This system increased the glucose concentration by 20.7% and the starch-based shikimate titer to 50.96 g L[-1], which showed the highest titer with starch as substrate. Then, the contact surface of E. coli was improved using a biofilm-based CdS-biohybrid system by light-driven system, which improved the NADH concentration by 83.3% and increased the NADH-dependent L-malate titer to 45.93 g L[-1]. Thus, the biofilm-based strategies can regulate cellular functions to increase the efficiency of microbial cell factories based on the optogenetics, light-driven, and metabolic engineering.}, }
@article {pmid38650271, year = {2021}, author = {Atnafu, T and Leta, S}, title = {A novel fragmented anode biofilm microbial fuel cell (FAB-MFC) integrated system for domestic wastewater treatment and bioelectricity generation.}, journal = {Bioresources and bioprocessing}, volume = {8}, number = {1}, pages = {112}, pmid = {38650271}, issn = {2197-4365}, abstract = {BACKGROUND: The critical MFC design challenge is to increase anode surface area. A novel FAB-MFC integrated system was developed and evaluated for domestic wastewater treatment. It was operated in fed-batch flow mode at 1-3 days of HRT with 755 mg/L CODIN and 0.76 kg-COD/m[3]/day. The study includes anaerobic-MFC and aerobic-MFC integrated systems. Microbial electrode jacket dish (MEJ-dish) with hybrid dimension (HD) was invented, first time to authors' knowledge, to boost anode biofilm growth. The treatment system with MEJ+ (FAB) and MEJ- (MFC) anode are called FAB-MFC and MFC, respectively.<br><br>RESULTS: Fragmented variable anode biofilm thickness was observed in FAB than MFC. The FAB-MFC (FAB+) simple technique increases the anode biofilm thickness by&#x2009;~&#x2009;5 times MFC. Due to HD the anode biofilm was fragmented in FAB+ system than MFC. At the end of each treatment cycle, voltage drops. All FAB+&#x2009;integrated systems reduced voltage drop relative to MFC. FAB reduces voltage drops better than MFC in anaerobic-MFC from 6 to 20&#xa0;mV and aerobic-MFC from 35-47&#xa0;mV at 1 k&#x3a9; external load. The highest power density was achieved by FAB in anaerobic-MFC (FAB&#x2009;=&#x2009;104 mW/m[2], MFC&#x2009;=&#x2009;98 mW/m[2]) and aerobic-MFC integrated system (FAB&#x2009;=&#x2009;59 mW/m[2], MFC&#x2009;=&#x2009;42 mW/m[2]).<br><br>CONCLUSIONS: The &#x2206;COD and CE between FAB and MFC could not be concluded because both setups were inserted in the same reactor. The integrated system COD removal (78-97%) was higher than the solitary MFC treatment (68-78%). This study findings support the FAB+&#x2009;integrated system could be applied for real applications and improve performance. However, it might depend on influent COD, the microbial nature, and &#x2206;COD in FAB+ and MFC, which requires further study.}, }
@article {pmid38715287, year = {2018}, author = {Johani, K and Hu, H and Santos, L and Schiller, S and Deva, AK and Whiteley, G and Almatroudi, A and Vickery, K}, title = {Determination of bacterial species present in biofilm contaminating the channels of clinical endoscopes.}, journal = {Infection, disease &amp; health}, volume = {23}, number = {4}, pages = {189-196}, doi = {10.1016/j.idh.2018.06.003}, pmid = {38715287}, issn = {2468-0869}, abstract = {BACKGROUND: Outbreaks of endoscopy-related Carbapenem-resistant Enterobacteriaceae has highlighted failures in endoscope decontamination resulting in biofilm formation. Biofilms are tolerant to detergents and disinfectants. We evaluated decontaminated endoscope channels for residual bacterial contamination and biofilm presence.<br><br>METHODS: 64 channels were collected from 12 gastroscopes and 11 colonoscopes. Aerobic bacteria were isolated from inside the endoscope tubing by scrapping, sonication, and aerobic plate culture. Total number of contaminating bacteria was determined by quantitative real-time PCR with 16s rRNA eubacterial universal primers. Microbial diversity was assessed using next generation DNA sequencing. Biofilm presence was visually confirmed by confocal laser scanning and scanning electron microscopy.<br><br>RESULTS: 47% of channels were culture positive, with &#x3b1;-haemolytic Streptococci from gastroscopes and coliforms from colonoscopes the most frequently isolated species. Sphingomonas spp., Staphylococcus spp., Streptococcus spp., and Pseudomonas aeruginosa were also isolated. An average of 1.2&#xa0;&#xd7;&#xa0;10[3] bacteria/cm contaminated air-water channels, 2.8&#xa0;&#xd7;&#xa0;10[2] and 6.6&#xa0;&#xd7;&#xa0;10[2] bacteria/cm contaminated gastroscope and colonoscope working channels, respectively. Biofilm was on all 39 channels examined and was principally composed of environmental bacteria, although all samples contained potential pathogens.<br><br>CONCLUSION: Biofilm is present on many endoscope channels obtained from Australian hospitals. Any soil including biofilm can compromise disinfectant action.}, }
@article {pmid38494030, year = {2024}, author = {Alrammah, F and Xu, L and Patel, N and Kontis, N and Rosado, A and Gu, T}, title = {Conductive magnetic nanowires accelerated electron transfer between C1020 carbon steel and Desulfovibrio vulgaris biofilm.}, journal = {The Science of the total environment}, volume = {925}, number = {}, pages = {171763}, doi = {10.1016/j.scitotenv.2024.171763}, pmid = {38494030}, issn = {1879-1026}, mesh = {Humans ; Steel ; *Desulfovibrio vulgaris ; Electrons ; Carbon/metabolism ; *Nanowires ; Biofilms ; *Desulfovibrio/metabolism ; Corrosion ; Sulfates/metabolism ; Weight Loss ; }, abstract = {Microbial biofilms are behind microbiologically influenced corrosion (MIC). Sessile cells in biofilms are many times more concentrated volumetrically than planktonic cells in the bulk fluids, thus providing locally high concentrations of chemicals. More importantly, "electroactive" sessile cells in biofilms are capable of utilizing extracellularly supplied electrons (e.g., from elemental Fe) for intracellular reduction of an oxidant such as sulfate in energy metabolism. MIC directly caused by anaerobic biofilms is classified into two main types based on their mechanisms: extracellular electron transfer MIC (EET-MIC) and metabolite MIC (M-MIC). Sulfate-reducing bacteria (SRB) are notorious for their corrosivity. They can cause EET-MIC in carbon steel, but they can also secrete biogenic H2S to corrode other metals such as Cu directly via M-MIC. This study investigated the use of conductive magnetic nanowires as electron mediators to accelerate and thus identify EET-MIC of C1020 by Desulfovibrio vulgaris. The presence of 40 ppm (w/w) nanowires in ATCC 1249 culture medium at 37 °C resulted in 45 % higher weight loss and 57 % deeper corrosion pits after 7-day incubation. Electrochemical tests using linear polarization resistance and potentiodynamic polarization supported the weight loss data trend. These findings suggest that conductive magnetic nanowires can be employed to identify EET-MIC. The use of insoluble 2 μm long nanowires proved that the extracellular section of the electron transfer process is a bottleneck in SRB MIC of carbon steel.}, }
@article {pmid38494003, year = {2024}, author = {Xiao, K and Abbt-Braun, G and Pleitner, R and Horn, H}, title = {Effect of ciprofloxacin on the one-stage partial nitrification and anammox biofilm system: A multivariate analysis focusing on size-fractionated organic components.}, journal = {Chemosphere}, volume = {355}, number = {}, pages = {141731}, doi = {10.1016/j.chemosphere.2024.141731}, pmid = {38494003}, issn = {1879-1298}, mesh = {*Ciprofloxacin/pharmacology ; *Nitrification ; Anaerobic Ammonia Oxidation ; Anti-Bacterial Agents/pharmacology ; Biofilms ; Bioreactors ; Nitrogen ; Sewage ; Oxidation-Reduction ; Denitrification ; }, abstract = {The impact of ciprofloxacin (CIP) in the partial nitrification and anammox biofilm system was investigated by multivariate analysis, focusing on size-fractionated organic components. The CIP dose of 10 μg/L did not inhibit the total nitrogen (TN) removal efficiency, even though the abundance of antibiotic resistant genes (ARGs) (i.e., qnrD, qnrB, qnrA, qnrS, and arcA) was elevated. However, a gradual higher CIP dosing up to 100 μg/L inhibited the TN removal efficiency, while the abundance of ARGs was still increased. Moreover, both the TN removal efficiency and the abundant ARGs were dwindled at 470 μg/L of CIP. As the CIP dose increased from 0 to 100 μg/L, the abundance of high molecular weight (MW) fractions (14,000 to 87,000 Da; 1000 to 14,000 Da) and humic/fulvic acid-like components in the soluble extracellular polymeric substances (HSS) decreased, with more increases of low MW (84-1000 Da; less than 84 Da) fractions and soluble microbial by-products in soluble extracellular polymeric substances (SMPS). Continuously increasing the CIP dose till 470 μg/L, an inverse trend of the changes of these organic components was noted, along with clear reductions of the microbial diversity and richness, and the abundance of key functional genes responsible for nitrogen removal. The predominance of functional gene amoA (related with ammonia oxidizing bacteria) was more significantly with more distribution of SMPS with relatively low MW and less distribution of HSS with relatively high MW, as well as polymer decomposing microorganisms such as Bryobacteraceae and the unclassified Saprospirales.}, }
@article {pmid38493904, year = {2024}, author = {Wei, PW and Wang, X and Wang, C and Chen, M and Liu, MZ and Liu, WX and He, YL and Xu, GB and Zheng, XH and Zhang, H and Liu, HM and Wang, B}, title = {Ginkgo biloba L. exocarp petroleum ether extract inhibits methicillin-resistant Staphylococcus aureus by modulating ion transport, virulence, and biofilm formation in vitro and in vivo.}, journal = {Journal of ethnopharmacology}, volume = {328}, number = {}, pages = {117957}, doi = {10.1016/j.jep.2024.117957}, pmid = {38493904}, issn = {1872-7573}, mesh = {Animals ; Mice ; *Methicillin-Resistant Staphylococcus aureus ; Ginkgo biloba/chemistry ; Virulence ; Gentian Violet/pharmacology ; Prospective Studies ; Plant Extracts/pharmacology ; Solvents/chemistry ; Anti-Bacterial Agents/pharmacology ; Biofilms ; Microbial Sensitivity Tests ; *Acetates ; *Alkanes ; }, abstract = {As reported in the Ancient Chinese Medicinal Books, Ginkgo biloba L. fruit has been used as a traditional Chinese medicine for the treatment asthma and cough or as a disinfectant. Our previous study demonstrated that G. biloba exocarp extract (GBEE), an extract of a traditional Chinese herb, inhibits the formation of methicillin-resistant Staphylococcus aureus (MRSA) biofilms. However, GBEE is a crude extract that contains many components, and the underlying mechanisms of purified GBEE fractions extracted with solvents of different polarities are unknown.<br><br>AIM OF THE STUDY: This study aimed to investigate the different components in GBEE fractions extracted with solvents of different polarities and their antibacterial effects and mechanisms against MRSA and Staphylococcus haemolyticus biofilms both in vitro and in vivo.<br><br>METHODS: The components in different fractions were detected by high-performance liquid chromatography-high resolution mass spectrometry (HPLC-HRMS). Microbroth dilution assays and time growth curves were used to determine the antibacterial effects of the fractions on 15 clinical bacterial isolates. Crystal violet staining, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were utilized to identify the fractions that affected bacterial biofilm formation. The potential MRSA targets of the GBEE fraction obtained with petroleum ether (PE), denoted GBEE-PE, were screened by transcriptome sequencing, and the gene expression profile was verified by quantitative polymerase chain reaction (qPCR).<br><br>RESULTS: HPLC-HRMS analysis revealed that the four GBEE fractions (extracted with petroleum ether, ethyl acetate, n-butanol, and water) contained different ginkgo components, and the antibacterial effects decreased as the polarity of the extraction solvent increased. The antibacterial activity of GBEE-PE was greater than that of the GBEE fraction extracted with ethyl acetate (EA). GBEE-PE improved H. illucens survival and reduced MRSA colonization in model mouse organs. Crystal violet staining and SEM and TEM analyses revealed that GBEE-PE inhibited MRSA and S. haemolyticus biofilm formation. Transcriptional analysis revealed that GBEE-PE inhibits MRSA biofilms by altering ion transport, cell wall metabolism and virulence-related gene expression. In addition, the LO2 cell viability and H. illucens toxicity assay data showed that GBEE-PE at 20 mg/kg was nontoxic.<br><br>CONCLUSION: The GBEE fractions contained different components, and their antibacterial effects decreased with increases in the polarity of the extraction solvent. GBEE-PE limited MRSA growth and biofilm formation by affecting ion transport, cell wall synthesis, and virulence-related pathways. This research provides a more detailed overview of the mechanism by which GBEE-PE inhibits MRSA both in vitro and in vivo and suggests that GBEE-PE is a new prospective antimicrobial with the potential to be used in MRSA therapeutics in the future.}, }
@article {pmid38493743, year = {2024}, author = {Li, Y and Dai, J and Ma, Y and Yao, Y and Yu, D and Shen, J and Wu, L}, title = {The mitigation potential of synergistic quorum quenching and antibacterial properties for biofilm proliferation and membrane biofouling.}, journal = {Water research}, volume = {255}, number = {}, pages = {121462}, doi = {10.1016/j.watres.2024.121462}, pmid = {38493743}, issn = {1879-2448}, abstract = {Biofouling has been a persistent problem hindering the application of membranes in water treatment, and quorum quenching has been identified as an effective method for mitigating biofouling, but surface accumulation of live bacteria still induces biofilm secretion, which poses a significant challenge for sustained prevention of membrane biofouling. In this study, we utilized quercetin, a typical flavonoid with the dual functions of quorum quenching and bacterial inactivation, to evaluate its role in preventing biofilm proliferation and against biofouling. Quercetin exhibited excellent antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), and the decreased bioactivity was positively correlated with the quercetin concentration, with inhibition rates of 53.1 % and 57.4 %, respectively, at the experimental concentrations. The RT-qPCR results demonstrated that quercetin inhibited AI-2 of E. coli and AGR of S. aureus mediated quorum sensing system, and reduced the expression of genes such as adhesion, virulence, biofilm secretion, and key regulatory proteases. As a result, the bacterial growth cycle was retarded and the biomass and biofilm maturation cycles were alleviated with the synergistic effect of quorum quenching and antibacterial activity. In addition, membrane biofouling was significantly declined in the dynamic operation experiments, dead cells in the biofilm overwhelmingly dominated, and the final normalized water fluxes were increased by more than 49.9 % and 34.5 % for E. coli and S. aureus, respectively. This work demonstrates the potential for mitigating biofouling using protocols that quorum quenching and inactivate bacteria, also provides a unique and long-lasting strategy to alleviate membrane fouling.}, }
@article {pmid38493145, year = {2024}, author = {Zhao, Y and Wu, Y and Xu, Q and Liu, Y and Song, Z and Han, H}, title = {H2O2 self-supplying and GSH-depleting nanosystem for amplified NIR mediated-chemodynamic therapy of MRSA biofilm-associated infections.}, journal = {Journal of nanobiotechnology}, volume = {22}, number = {1}, pages = {117}, pmid = {38493145}, issn = {1477-3155}, support = {22277036//National Natural Science Foundation of China/ ; }, mesh = {Humans ; Hydrogen Peroxide/pharmacology ; *Methicillin-Resistant Staphylococcus aureus ; Reactive Oxygen Species ; Anti-Bacterial Agents/pharmacology ; Biofilms ; Glutathione ; *Bacterial Infections ; *Neoplasms ; Cell Line, Tumor ; Tumor Microenvironment ; }, abstract = {Reactive oxygen species (ROS) has emerged as potent therapeutic agents for biofilm-associated bacterial infections. Chemodynamic therapy (CDT), involving the generation of high-energy ROS, displays great potential in the therapy of bacterial infections. However, challenges such as insufficient hydrogen peroxide (H2O2) and over-expressed glutathione (GSH) levels within the microenvironment of bacterial biofilms severely limit the antibacterial efficacy of CDT. Herein, we have developed a multifunctional nanoplatform (CuS@CaO2@Dex) by integrating copper sulfide (CuS) and calcium peroxide (CaO2) into dextran (Dex)-coated nanoparticles. This innovative platform enhanced ROS generation for highly efficient biofilm elimination by simultaneously supplying H2O2 and depleting GSH. The Dex-coating facilitated the penetrability of CuS@CaO2@Dex into biofilms, while CaO2 generated a substantial amount of H2O2 in the acidic biofilm microenvironment. CuS, through a Fenton-like reaction, catalyzed the conversion of self-supplied H2O2 into hydroxyl radicals (•OH) and consumed the overexpressed GSH. Additionally, the incorporation of near-infrared II (NIR II) laser irradiation enhanced the photothermal properties of CuS, improving the catalytic efficiency of the Fenton-like reaction for enhanced antibacterial effects. In vivo experiments have demonstrated that CuS@CaO2@Dex exhibited remarkable antibacterial and antibiofilm efficacy, exceptional wound healing capabilities, and notable biosafety. In summary, the Dex-coated nanoplatform proposed in this study, with its self-sterilization capability through ROS, holds significant potential for future biomedical applications.}, }
@article {pmid38492828, year = {2024}, author = {Malik, M and Das, S and Chakraborty, P and Paul, P and Roy, R and Das Gupta, A and Sarkar, S and Chatterjee, S and Maity, A and Dasgupta, M and Sarker, RK and Tribedi, P}, title = {Application of cuminaldehyde and ciprofloxacin for the effective control of biofilm assembly of Pseudomonas aeruginosa: A combinatorial study.}, journal = {Microbial pathogenesis}, volume = {190}, number = {}, pages = {106624}, doi = {10.1016/j.micpath.2024.106624}, pmid = {38492828}, issn = {1096-1208}, mesh = {*Biofilms/drug effects ; *Ciprofloxacin/pharmacology ; *Pseudomonas aeruginosa/drug effects/physiology ; *Microbial Sensitivity Tests ; *Anti-Bacterial Agents/pharmacology ; *Benzaldehydes/pharmacology ; *Reactive Oxygen Species/metabolism ; Virulence Factors ; Cymenes/pharmacology ; Drug Synergism ; Cell Membrane Permeability/drug effects ; Humans ; }, abstract = {Pseudomonas aeruginosa is widely associated with biofilm-mediated antibiotic resistant chronic and acute infections which constitute a persistent healthcare challenges. Addressing this threat requires exploration of novel therapeutic strategies involving the combination of natural compounds and conventional antibiotics. Hence, our study has focused on two compounds; cuminaldehyde and ciprofloxacin, which were strategically combined to target the biofilm challenge of P. aeruginosa. The minimum inhibitory concentration (MIC) of cuminaldehyde and ciprofloxacin was found to be 400 μg/mL and 0.4 μg/mL, respectively. Moreover, the fractional inhibitory concentration index (FICI = 0.62) indicated an additive interaction prevailed between cuminaldehyde and ciprofloxacin. Subsequently, sub-MIC doses of cuminaldehyde (25 μg/mL) and ciprofloxacin (0.05 μg/mL) were selected for an array of antibiofilm assays which confirmed their biofilm inhibitory potential without exhibiting any antimicrobial activity. Furthermore, selected doses of the mentioned compounds could manage biofilm on catheter surface by inhibiting and disintegrating existing biofilm. Additionally, the test combination of the mentioned compounds reduced virulence factors secretion, accumulated reactive oxygen species and increased cell-membrane permeability. Thus, the combination of cuminaldehyde and ciprofloxacin demonstrates potential in combating biofilm-associated Pseudomonal threats.}, }
@article {pmid38491527, year = {2024}, author = {Milech, A and Braga, CQ and Dos Santos Bermann, C and de Souza, JF and Fajardo, AR and Vianna, &#xc9;S and Oliveira, CB}, title = {New artificial hematophagy system with attractive polymeric biofilm for maintenance of Culex quinquefasciatus (Diptera: Culicidae) in the laboratory.}, journal = {Parasites &amp; vectors}, volume = {17}, number = {1}, pages = {136}, pmid = {38491527}, issn = {1756-3305}, mesh = {Female ; Animals ; *Culicidae ; Paraffin ; Ovum ; *Culex ; Oviposition ; Larva ; }, abstract = {BACKGROUND: Maintaining mosquito colonies in the laboratory requires a blood supply so that females' oocytes can mature and oviposition can take place. In this study, a new artificial hematophagy system for colonization and maintenance of Culex quinquefasciatus in the laboratory was developed and tested.<br><br>METHODS: We developed an attractive polymeric biofilm including 25% L-lactic acid for use as a membrane in an artificial hematophagy system and compared the feeding rate of females with Parafilm-M[&#xae;]. We also evaluated the oviposition rate, larval survival and adult emergence of females fed through the attractive biofilm.<br><br>RESULTS: The average percentage of female Cx. quinquefasciatus fed through the attractive biofilm was 87%, while only 20% became engorged with Parafilm-M[&#xae;] (p&#x2009;<&#x2009;0.0001). Feeding through the attractive biofilm developed in this study produced high levels of evaluated biological parameters; the percentage of egg laying by females that underwent artificial hematophagy through the biofilm was 90%, with an average of 158 eggs per raft. From these eggs, 97% of the larvae hatched, of which 95% reached the pupal stage. The adult emergence rate corresponded to 93% of pupae.<br><br>CONCLUSIONS: Insects fed with attractant through the biofilm system had a higher engorgement rate compared to those fed through Parafilm-M[&#xae;]. Our study is preliminary and suggests that polymeric biofilm has great potential for artificially feeding mosquitoes in the laboratory. Based on this research, new studies will be carried out with biofilm and different systems.}, }
@article {pmid38490460, year = {2024}, author = {Zou, S and Ma, Y and Ding, W and Jiang, Y and Chen, X and Chen, J and Gao, H and Xue, Y and Zheng, Y}, title = {Efficient production of R-2-(4-hydroxyphenoxy) propionic acid by Beauveria bassiana using biofilm-based two-stage fermentation.}, journal = {Bioresource technology}, volume = {399}, number = {}, pages = {130588}, doi = {10.1016/j.biortech.2024.130588}, pmid = {38490460}, issn = {1873-2976}, mesh = {Fermentation ; *Beauveria/chemistry ; Bioreactors ; Propionates ; }, abstract = {In this work, a novel biofilm-based fermentation of Beauveria bassiana was employed to convert R-2- phenoxypropionic acid (R-PPA) to R-2-(4-hydroxyphenoxy) propionic acid (R-HPPA). The biofilm culture model of Beauveria bassiana produced a significantly higher R-HPPA titer than the traditional submerged fermentation method. Mannitol dosage, tryptone dosage, and initial pH were the factors that played a significant role in biofilm formation and R-HPPA synthesis. Under the optimal conditions, the maximum R-HPPA titer and productivity approached 22.2 g/L and 3.2 g/(L·d), respectively. A two-stage bioreactor combining agitation and static incubation was developed to further increase R-HPPA production. The process was optimized to achieve 100 % conversion of R-PPA, with a maximum R-HPPA titer of 50 g/L and productivity of 3.8 g/(L·d). This newly developed biofilm-based two-stage fermentation process provides a promising strategy for the industrial production of R-HPPA and related hydroxylated aromatic compounds.}, }
@article {pmid38490139, year = {2024}, author = {Zheng, Y and Zhang, W and Tang, B and Bin, L and Ding, J and Zheng, Y and Zhang, Z}, title = {Corrigendum to "Membrane fouling mechanism of biofilm-membrane bioreactor (BF-MBR): Pore blocking model and membrane cleaning" [Bioresour. Technol. 250 (2018) 398-405].}, journal = {Bioresource technology}, volume = {399}, number = {}, pages = {130564}, doi = {10.1016/j.biortech.2024.130564}, pmid = {38490139}, issn = {1873-2976}, }
@article {pmid38489102, year = {2024}, author = {Tayyeb, JZ and Priya, M and Guru, A and Kishore Kumar, MS and Giri, J and Garg, A and Agrawal, R and Mat, KB and Arockiaraj, J}, title = {Multifunctional curcumin mediated zinc oxide nanoparticle enhancing biofilm inhibition and targeting apoptotic specific pathway in oral squamous carcinoma cells.}, journal = {Molecular biology reports}, volume = {51}, number = {1}, pages = {423}, pmid = {38489102}, issn = {1573-4978}, mesh = {Humans ; *Zinc Oxide/pharmacology/chemistry ; *Curcumin/pharmacology ; *Metal Nanoparticles/chemistry ; Antioxidants/pharmacology ; *Anti-Infective Agents ; Anti-Bacterial Agents/pharmacology/chemistry ; *Carcinoma, Squamous Cell/drug therapy ; *Mouth Neoplasms/drug therapy ; Biofilms ; Plant Extracts/chemistry ; Microbial Sensitivity Tests ; *Sulfonic Acids ; *Benzothiazoles ; }, abstract = {BACKGROUND: Oral health remains a significant global concern with the prevalence of oral pathogens and the increasing incidence of oral cancer posing formidable challenges. Additionally, the emergence of antibiotic-resistant strains has complicated treatment strategies, emphasizing the urgent need for alternative therapeutic approaches. Recent research has explored the application of plant compounds mediated with nanotechnology in oral health, focusing on the antimicrobial and anticancer properties.<br><br>METHODS: In this study, curcumin (Cu)-mediated zinc oxide nanoparticles (ZnO NPs) were synthesized and characterized using SEM, EDAX, UV spectroscopy, FTIR, and XRD to validate their composition and structural features. The antioxidant and antimicrobial activity of ZnO-CU NPs was investigated through DPPH, ABTS, and zone of inhibition assays. Apoptotic assays and gene expression analysis were performed in KB oral squamous carcinoma cells to identify their anticancer activity.<br><br>RESULTS: ZnO-CU NPs showcased formidable antioxidant prowess in both DPPH and ABTS assays, signifying their potential as robust scavengers of free radicals. The determined minimal inhibitory concentration of 40&#xa0;&#xb5;g/mL against dental pathogens underscored the compelling antimicrobial attributes of ZnO-CU NPs. Furthermore, the interaction analysis revealed the superior binding affinity and intricate amino acid interactions of ZnO-CU NPs with receptors on dental pathogens. Moreover, in the realm of anticancer activity, ZnO-CU NPs exhibited a dose-dependent response against Human Oral Epidermal Carcinoma KB cells at concentrations of 10&#xa0;&#xb5;g/mL, 20&#xa0;&#xb5;g/mL, 40&#xa0;&#xb5;g/mL, and 80&#xa0;&#xb5;g/mL. Unraveling the intricate mechanism of apoptotic activity, ZnO-CU NPs orchestrated the upregulation of pivotal genes, including BCL2, BAX, and P53, within the KB cells.<br><br>CONCLUSIONS: This multifaceted approach, addressing both antimicrobial and anticancer activity, positions ZnO-CU NPs as a compelling avenue for advancing oral health, offering a comprehensive strategy for tackling both oral infections and cancer.}, }
@article {pmid38489099, year = {2024}, author = {Abo-Alella, D and Abdelmoniem, W and Tantawy, E and Asaad, A}, title = {Biofilm-producing and carbapenems-resistant Escherichia coli nosocomial uropathogens: a cross-sectional study.}, journal = {International microbiology : the official journal of the Spanish Society for Microbiology}, volume = {27}, number = {6}, pages = {1633-1640}, pmid = {38489099}, issn = {1618-1905}, mesh = {*Biofilms/drug effects/growth &amp; development ; Humans ; Cross-Sectional Studies ; *Cross Infection/microbiology ; *Escherichia coli Infections/microbiology ; *Anti-Bacterial Agents/pharmacology ; Female ; Male ; *Uropathogenic Escherichia coli/drug effects/genetics/physiology/isolation &amp; purification ; Middle Aged ; *Urinary Tract Infections/microbiology ; Carbapenems/pharmacology ; Adult ; Aged ; Risk Factors ; Microbial Sensitivity Tests ; beta-Lactamases/genetics/metabolism ; Tertiary Care Centers ; }, abstract = {OBJECTIVES: This cross-sectional study aims to determine the incidence and potential risk factors associated with biofilm-producing uropathogenic Escherichia coli (UPEC) nosocomial strains from a tertiary care hospital and to examine the prospective correlation between biofilm generation and antibiotic resistance phenotypes and genotypes.<br><br>METHODS: A total of 130 UPEC nosocomial isolates were identified, their biofilm formation was quantified using a modified microtiter plate assay, and their antibiotic susceptibilities were assessed utilizing the disc diffusion method. Isolates were then subjected to PCR assays targeting blaKPC, blaVIM, blaIMP, and blaOXA48 genes.<br><br>RESULTS: Over half of the isolates (n&#x2009;=&#x2009;76, 58.5%) were biofilm producers. Among 17 carbapenem-resistant isolates, 6 (42.9%) isolates harbored the blaOXA48 gene, and only 1 (9.1%) isolate was positive for the blaVIM gene. Prior antibiotic therapy (aOR 15.782, p 0.000) and diabetes mellitus DM (aOR 11.222, p 0.016) were the significant risk factors associated with biofilm production, as determined by logistic regression analysis of the data. In addition, gentamicin resistance was the only statistically significant antibiotic resistance pattern associated with biofilm production (aOR 9.113, p 0.02).<br><br>CONCLUSIONS: The findings of this study emphasize the significance of implementing proper infection control measures to avoid the horizontal spread of biofilm formation and associated antimicrobial resistance patterns among UPEC nosocomial strains.}, }
@article {pmid38489041, year = {2024}, author = {Bhavya, JN and Anugna, SS and Premanath, R}, title = {Sub-inhibitory concentrations of colistin and imipenem impact the expression of biofilm-associated genes in Acinetobacter baumannii.}, journal = {Archives of microbiology}, volume = {206}, number = {4}, pages = {169}, pmid = {38489041}, issn = {1432-072X}, support = {N(DU)/RD/Grant/NUCSER/2020-20/04-9//Nitte research grant/ ; }, mesh = {Humans ; Imipenem/pharmacology/therapeutic use ; Colistin/pharmacology/therapeutic use ; *Acinetobacter baumannii/genetics ; *Acinetobacter Infections/drug therapy/microbiology ; Anti-Bacterial Agents/pharmacology/therapeutic use ; Biofilms ; Microbial Sensitivity Tests ; Drug Resistance, Multiple, Bacterial ; }, abstract = {Acinetobacter baumannii is an opportunistic pathogen that is responsible for nosocomial infections. Imipenem and colistin are drugs that are commonly used to treat severe infections caused by A. baumannii, such as sepsis, ventilator-associated pneumonia, and bacteremia. However, some strains of A. baumannii have become resistant to these drugs, which is a concern for public health. Biofilms produced by A. baumannii increase their resistance to antibiotics and the cells within the inner layers of biofilm are exposed to sub-inhibitory concentrations (sub-MICs) of antibiotics. There is limited information available regarding how the genes of A. baumannii are linked to biofilm formation when the bacteria are exposed to sub-MICs of imipenem and colistin. Thus, this study's objective was to explore this relationship by examining the genes involved in biofilm formation in A. baumannii when exposed to low levels of imipenem and colistin. The study found that exposing an isolate of A. baumannii to low levels of these drugs caused changes in their drug susceptibility pattern. The relative gene expression profiles of the biofilm-associated genes exhibited a change in their expression profile during short-term and long-term exposure. This study highlights the potential consequences of overuse and misuse of antibiotics, which can help bacteria become resistant to these drugs.}, }
@article {pmid38488341, year = {2024}, author = {Gao, Q and Chu, X and Yang, J and Guo, Y and Guo, H and Qian, S and Yang, YW and Wang, B}, title = {An Antibiotic Nanobomb Constructed from pH-Responsive Chemical Bonds in Metal-Phenolic Network Nanoparticles for Biofilm Eradication and Corneal Ulcer Healing.}, journal = {Advanced science (Weinheim, Baden-Wurttemberg, Germany)}, volume = {11}, number = {22}, pages = {e2309086}, pmid = {38488341}, issn = {2198-3844}, support = {ZY2019017//Wenzhou key program of scientific and technological innovation/ ; 2021ZA091//Zhejiang Provincial Traditional Chinese Medicine Science and Technology Project/ ; LR21H180001//Natural Science Foundation of Zhejiang Province/ ; }, mesh = {*Biofilms/drug effects ; Animals ; *Corneal Ulcer/drug therapy ; *Anti-Bacterial Agents/pharmacology ; *Nanoparticles/chemistry ; Hydrogen-Ion Concentration ; *Tobramycin/pharmacology/chemistry/administration &amp; dosage ; *Disease Models, Animal ; *Pseudomonas aeruginosa/drug effects ; Wound Healing/drug effects ; Drug Delivery Systems/methods ; Pseudomonas Infections/drug therapy ; }, abstract = {In the treatment of refractory corneal ulcers caused by Pseudomonas aeruginosa, antibacterial drugs delivery faces the drawbacks of low permeability and short ocular surface retention time. Hence, novel positively-charged modular nanoparticles (NPs) are developed to load tobramycin (TOB) through a one-step self-assembly method based on metal-phenolic network and Schiff base reaction using 3,4,5-trihydroxybenzaldehyde (THBA), ε-poly-ʟ-lysine (EPL), and Cu[2+] as matrix components. In vitro antibacterial test demonstrates that THBA-Cu-TOB NPs exhibit efficient instantaneous sterilization owing to the rapid pH responsiveness to bacterial infections. Notably, only 2.6 µg mL[-1] TOP is needed to eradicate P. aeruginosa biofilm in the nano-formed THBA-Cu-TOB owing to the greatly enhanced penetration, which is only 1.6% the concentration of free TOB (160 µg mL[-1]). In animal experiments, THBA-Cu-TOB NPs show significant advantages in ocular surface retention, corneal permeability, rapid sterilization, and inflammation elimination. Based on molecular biology analysis, the toll-like receptor 4 and nuclear factor kappa B signaling pathways are greatly downregulated as well as the reduction of inflammatory cytokines secretions. Such a simple and modular strategy in constructing nano-drug delivery platform offers a new idea for toxicity reduction, physiological barrier penetration, and intelligent drug delivery.}, }
@article {pmid38486820, year = {2024}, author = {Edayadulla, N and Divakaran, D and Chandraraj, SS and Suyambulingam, I and Jayamani, E and Sanjay, MR and Siengchin, S}, title = {Isolation and characterization of novel bioplasticizers from rose (Rosa damascena Mill.) petals and its suitability investigation for poly (butylene adipate-co-terephthalate) biofilm applications.}, journal = {3 Biotech}, volume = {14}, number = {4}, pages = {110}, pmid = {38486820}, issn = {2190-572X}, abstract = {The current growing environmental awareness has forced the use of biodegradable plasticizers, which are sustainable and abundant in plant resources. Rose petal plasticizers (RPP) act as an actual substitute for chemical plasticizers in this situation as they are biocompatible and biodegradable. Chemical procedures like amination, alkalization, and surface catalysis are used to extract the natural emollients from rose petals. XRD, FT-IR, and UV studies were used to understand the characteristics of the rose petal plasticizer. Based on the XRD data, the RPP's crystallinity size (CS) and crystallinity index (CI) values were determined to be 9.36 nm and 23.87%, respectively. The surface morphology of the isolated plasticizer is investigated using SEM, EDAX analysis and AFM. RPP surface pores with rough surfaces are visible in SEM images, which make them appropriate for plasticizing novel bioplastics with superior mechanical qualities. The plasticizer's heat degradation behaviour is investigated using thermogravimetric and differential thermogram analysis curves. Following the characterization of the synthesised molecules, the plasticization effect was examined using a biodegradable polymer matrix called poly (butylene adipate-co-terephthalate) (PBAT). The reinforcement interface was also examined using scanning electron microscopy analysis. RPP-reinforced films demonstrated greater flexibility and superior surface compatibility at a 5% loading compared to PBAT-only films. Based on a number of reported features, RPP could be a great plasticizer to address future environmental problems.}, }
@article {pmid38485676, year = {2024}, author = {Nasrollahian, S and Pourmoshtagh, H and Sabour, S and Hadi, N and Azimi, T and Soleiman-Meigooni, S}, title = {Biofilm Formation in Mycobacterial Genus; Mechanism of Biofilm Formation and Anti-Mycobacterial Biofilm Agents.}, journal = {Current pharmaceutical biotechnology}, volume = {}, number = {}, pages = {}, doi = {10.2174/0113892010277107240227054933}, pmid = {38485676}, issn = {1873-4316}, abstract = {Mycobacterium tuberculosis, Mycobacterium leprae, and non-tuberculous mycobacteria (NTM) are among the most significant human pathogens within the Mycobacterium genus. These pathogens can infect people who come into contact with biomaterials or have chronic illnesses. A characteristic pathogenic trait of mycobacteria is the development of biofilms, which involves several molecules, such as the GroEL1 chaperone, glycopeptidolipids, and shorter-chain mycolic acids. Bacterial behavior is influenced by nutrients, ions, and carbon sources, which also play a regulatory role in biofilm development. Compared to their planktonic phase, mycobacterial biofilms are more resilient to environmental stresses and disinfectants. Mycobacteria that produce biofilms have been found in several environmental studies, particularly in water systems. NTM can cause respiratory problems in individuals with underlying illnesses such as cystic fibrosis, bronchiectasis, and old tuberculosis scars. Mycobacteria that grow slowly, like those in the Mycobacterium avium complex (MAC), or rapidly, like Mycobacterium abscessus, can be pathogens. Infections related to biomaterials represent a significant category of biofilm-associated infections, with rapidly growing mycobacteria being the most frequently identified organisms. A biofilm produced by M. tuberculosis can contribute to caseous necrosis and cavity formation in lung tissue. Additionally, M. tuberculosis forms biofilms on clinical biomaterials. Biofilm formation is a major contributor to antimicrobial resistance, providing defense against drugs that would typically be effective against these bacteria in their planktonic state. The antibiotic resistance of biofilm-forming microbes may render therapy ineffective, necessitating the physical removal of biofilms to cure the infection. Recently, new approaches have been developed with potential anti-biofilm compounds to increase treatment effectiveness. Understanding biofilms is crucial for the appropriate treatment of various NTM diseases, and the recent discovery of M. tuberculosis biofilms has opened up a new field of study. This review focuses on the biofilm formation of the Mycobacterial genus, the mechanisms of biofilm formation, and anti-mycobacterial biofilm agents.}, }
@article {pmid38484996, year = {2024}, author = {Mkpuma, VO and Moheimani, NR and Ennaceri, H}, title = {Biofilm cultivation of chlorella species. MUR 269 to treat anaerobic digestate food effluent (ADFE): Total ammonia nitrogen (TAN) concentrations effect.}, journal = {Chemosphere}, volume = {354}, number = {}, pages = {141688}, doi = {10.1016/j.chemosphere.2024.141688}, pmid = {38484996}, issn = {1879-1298}, mesh = {*Chlorella ; Ammonia ; Anaerobiosis ; Food ; *Microalgae ; Biomass ; Nitrogen ; }, abstract = {Microalgal-based treatment of anaerobic digestate food effluent (ADFE) has been found to be efficient and effective. However, turbidity and high total ammonia nitrogen (TAN)) content of ADFE is a major setback, requiring significant dilution. Although the possibility of growing microalgae in a high-strength ADFE with minimal dilution has been demonstrated in suspension cultures, such effluents remain highly turbid and affect the light path in suspension cultures. Here, the feasibility of growing Chlorella sp.MUR 269 in biofilm to treat ADFE with high TAN concentrations was investigated. Six different TAN concentrations in ADFE were evaluated for their effects on biofilm growth and nutrient removal by Chlorella sp. MUR 269 using the perfused biofilm technique. Biomass yields and productivities of this alga at various TAN concentrations (mg N NH3 L[-1]) were 55[a] (108 g m[-2] and 9.80 g m[-2] d[-1])>100[b] > 200[c] = 300[c] = 500[c] > 1000[d]. Growth was inhibited, resulting in a 28% reduction in yield of Chlorella biofilm when this alga was grown at 1000 mg N NH3 L[-1]. A survey of the photosynthetic parameters reveals evidence of stress occurring in the following sequence: 55 < 100<200 < 300<1000. A significant nutrient removal was observed across various TAN concentrations. The removal pattern also followed the concentration gradients except COD, where the highest removal occurred at 500 mg N NH3 L[-1]. Higher removal rates were seen at higher nutrient concentrations and declined gradually over time. In general, our results indicated that the perfused biofilm strategy is efficient, minimizes water consumption, offers easy biomass harvesting, and better exposure to light. Therefore, it can be suitable for treating turbid and concentrated effluent with minimal treatment to reduce the TAN concentration.}, }
@article {pmid38484992, year = {2024}, author = {Chandra Sarker, D and Bal Krishna, KC and Ginige, MP and Sathasivan, A}, title = {Effective chloramine management without "burn" in biofilm affected nitrifying tanks using a low dose of copper.}, journal = {Chemosphere}, volume = {354}, number = {}, pages = {141709}, doi = {10.1016/j.chemosphere.2024.141709}, pmid = {38484992}, issn = {1879-1298}, mesh = {*Chloramines ; *Copper ; Chlorine ; Nitrites ; Ammonia ; Biofilms ; Nitrification ; Bioreactors ; }, abstract = {This paper highlights the potential to effectively inhibit nitrification and restore chloramine levels using a low copper concentration in a biofilm-affected (surface-to-volume ratio 16 m[-1]) continuous-flow laboratory-scale chloraminated system. High nitrite and low chloramine containing tanks are always recovered with chlorine "burn" by water utilities. The "burn" is not only costly and operationally complex, but also compromises the water quality, public health, and customer relations. A laboratory system comprising five reactors connected in series was operated. Each reactor simulated conditions typically encountered in full-scale systems. Low amount of copper (0.1-0.2 mg-Cu L[-1]) was dosed once per day into nitrified reactors. At any given time, only one reactor was dosed with copper. Not only inhibition of nitrification, chloramine decay associated with bulk water, biofilm and sediments also improved. However, the improvement was quicker and more significant when the influent to the reactor contained a high chloramine and a low nitrite concentration. Ammonia oxidising microbes exhibited resilience when exposed to low copper and chloramine concentrations for an extended period. Chloramine decay due to planktonic microbes and chemical reactions in bulk water decreased more rapidly than decay attributed to biofilm and sediments. The concept "biostable residual chlorine" explained how copper and chloramine can inhibit nitrification. Once nitrification was inhibited, the chloramine supplied from upstream effectively continued to suppress downstream nitrification, and this effect lasted more than 50 days even at 22 °C. The findings could be used to develop short-term copper dosing strategies and prevent negative impacts of nitrification and breakpoint chlorination.}, }
@article {pmid38483493, year = {2024}, author = {Hanay, &#xd6; and Aksoy, Y and Çelik, A and Yegin, M}, title = {Modifying gas transfer membranes with nanoscale zero-valent iron: effects on membrane material properties, treatment performance, and biofilm thickness.}, journal = {Water science and technology : a journal of the International Association on Water Pollution Research}, volume = {89}, number = {5}, pages = {1195-1210}, doi = {10.2166/wst.2024.062}, pmid = {38483493}, issn = {0273-1223}, mesh = {*Polyvinyls ; *Biofilms ; Escherichia coli ; Iron ; Oxygen ; *Fluorocarbon Polymers ; }, abstract = {Excessive membrane biofilm growth on membrane fibers depends on various factors, with membrane properties playing a pivotal role in influencing microbial affinity for the membrane. To investigate the antibacterial impact of nano-sized zero-valent iron (nZVI) on membrane biofilm structure, pristine (polyvinylidene fluoride (PVDF)) only: HF-0 (PVDF:20/nZVI:0 w/w) and four gas transfer membranes (PVDF:nZVI at different concentrations: HF-1 (PVDF:20/nZVI:0.25 w/w), HF-2 (PVDF:20/nZVI:0.50 w/w), HF-3 (PVDF:20/nZVI:0.75 w/w), HF-4 (PVDF:20/nZVI:1.0 w/w)) were produced. These membranes were assessed for surface morphology, porosity, gas permeability, and biofilm thickness, which ultimately affect biochemical reaction rates in membrane biofilm reactors (MBfRs). Various MBfRs utilizing these gas transfer membranes were operated at different hydraulic retention times (HRTs) and oxygen pressures to assess chemical oxygen demand (COD) removal efficiency and nitrification performance. Incorporating nZVI into the PVDF polymer solution increased surface hydrophilicity and porosity but reduced Young's Modulus and oxygen diffusion coefficients. Confocal laser scanning microscopy (CLSM) analysis revealed an average biofilm thickness of 700 μm in HF-0, HF-1, and HF-3, with a 100 μm decrease in HF-2, even though Escherichia coli growth was observed in HF-3 fibers. Regardless of nZVI dosage, a significant decline in COD removal and nitrification rates occurred at low HRTs and gas pressures.}, }
@article {pmid38483489, year = {2024}, author = {An, N and Ma, L and Lian, D and Wang, S}, title = {Effect of salinity on denitrification, membrane fouling and bacterial community in a fixed-bed biofilm membrane reactor.}, journal = {Water science and technology : a journal of the International Association on Water Pollution Research}, volume = {89}, number = {5}, pages = {1124-1141}, doi = {10.2166/wst.2024.050}, pmid = {38483489}, issn = {0273-1223}, mesh = {*Denitrification ; *Salinity ; Biofilms ; Extracellular Polymeric Substance Matrix ; Bacteria ; Pseudomonas ; }, abstract = {In this study, a fixed-bed biofilm membrane bioreactor was used to assess denitrification and carbon removal performance, membrane fouling, composition, and the dynamics of microbial communities across 10 salinity levels. As salinity levels increased (from 0 to 30 g/L), the removal efficiency of total nitrogen and chemical oxygen demand decreased from 98 and 86% in Phase I to 25 and 45% in Phase X, respectively. Beyond a salinity level of 10 g/L, membrane fouling accelerated considerably. The analysis of fouling resistance distribution suggested that soluble microbial products (SMPs) were the primary cause of this phenomenon. The irregularity in microbial community succession reflected the varying adaptability of different bacteria to different salinity levels. The relative abundance of Sulfuritalea, Lentimircobium, Thauera, and Pseudomonas increased from 20.2 to 47.7% as the experiments progressed. Extracellular polymeric substances-related analysis suggested that Azospirillum plays a positive role in preserving the structural integrity of the biofilm carrier. The SMP-related analysis showed a positive correlation between Lentimircobium, Thauera, Pseudomonas, and the SMP content. These results suggested that these three bacterial genera significantly promoted the release of SMP under salt stress, which in turn led to severe membrane fouling.}, }
@article {pmid38482364, year = {2024}, author = {Wanja, FK and Omwenga, EO and Ngugi, CW and Maina, JN and Kiiru, JN}, title = {Genotypic characterization of bacterial isolates causing urinary tract infections among adults at Kiambu Level 5 Hospital, Kenya: selected extended-spectrum β-lactamase genes and biofilm formation.}, journal = {Access microbiology}, volume = {6}, number = {2}, pages = {}, pmid = {38482364}, issn = {2516-8290}, abstract = {The menace of antimicrobial resistance affecting public health is rising globally. Many pathogenic bacteria use mechanisms such as mutations and biofilm formation, significantly reducing the efficacy of antimicrobial agents. In this cross-sectional study, we aimed to determine the prevalence of selected extended-spectrum β-lactamase (ESβL) genes and analyse the biofilm formation abilities of the isolated bacteria causing urinary tract infection among adult patients seeking Medicare at Kiambu Level 5 Hospital, Kenya. The double-disc synergy test was used for phenotypic identification of ESβL-producing isolates, while microtitre plate assays with some modifications were used for the biofilm formation test. Ten isolates were bioassayed for ESβL genes out of 57 bacterial isolates obtained from urine samples. This study found the bla TEM genes to be the most prevalent ESβL type [10/10 (100 %)], followed by blaOXA and blaSHV genes at 4/10 (40 %) and 3/10 (30 %), respectively. In addition, co-carriage of blaTEM and blaSHV was 50 % lower than that of blaTEM+bla OXA genes at 66.7 % among Escherichia coli isolates studied. Biofilm formation was positive in 36/57 (63.2 %) of the isolates tested, with most being Gram-negative [25/36 (69.4 %)]. Escherichia coli [15/36 (41.7 %)], Klebsiella species [7/36 (19.4 %)] and Staphylococcus aureus [7/36 (19.4 %)] were the dominant biofilm formers. However, there was no significant difference in biofilm formation among all tested isolates, with all isolates recording P-values >0.05. In light of these findings, biofilm formation potential coupled with antimicrobial resistance genes in urinary tract infection isolates may lead to difficult-to-treat infections.}, }
@article {pmid38482344, year = {2024}, author = {Watson, F and Wilks, S and Chewins, J and Keevil, B}, title = {Efficiency and novelty of using environmental swabs for dry-surface biofilm recovery.}, journal = {Access microbiology}, volume = {6}, number = {2}, pages = {}, pmid = {38482344}, issn = {2516-8290}, abstract = {Studies on the epidemiology of dry-surface biofilms (DSBs) within healthcare settings have shown an almost universal distribution across frequently touched items. Despite a growing body of evidence for DSBs in hospitals, little attention has been paid to the recovery capacity of techniques used to detect these microbial communities. Biofilms are inherently difficult to remove from surfaces due to adhesive substances within their matrix and may act as sources of infection, but to what extent is largely unknown. In this study, we evaluate the recovery efficiencies of commonly used environmental swabs against DSBs containing 7.24 log10 Acinetobacter baumannii cm[-2], using a drip flow reactor and desiccation cycle. Biofilm presence was visually confirmed using episcopic differential interference contrast microscopy combined with epifluorescence and quantified using sonicated viable plate counts. The swab materials used comprised foam, viscose and cotton, all of which were pre-moistened using a buffer solution. The surfaces were vigorously swabbed by each material type and the resultant microbe populations for both swabs and remaining DSBs were quantified. Our results found foam-tipped swabs to be superior, detecting on average 30 % of the original DSB contamination; followed by viscose (6 %) and cotton (3 %). However, no distinct difference was revealed in the concentration of microbes remaining on the surface after swabbing for each swab type, suggesting there is variation in the capacity for each swab to release biofilm-associated micro-organisms. We conclude whilst environmental swabs do possess the ability to detect biofilms on dry surfaces, the reduced efficiencies are likely to cause an underestimation of the microbes present and should be considered during clinical application.}, }
@article {pmid38481050, year = {2024}, author = {Nguyen, KCT and Truong, PH and Thi, HT and Ho, XT and Nguyen, PV}, title = {Prevalence, multidrug resistance, and biofilm formation of Vibrio parahaemolyticus isolated from fish mariculture environments in Cat Ba Island, Vietnam.}, journal = {Osong public health and research perspectives}, volume = {15}, number = {1}, pages = {56-67}, pmid = {38481050}, issn = {2210-9099}, abstract = {BACKGROUND: Vibrio parahaemolyticus is a major foodborne pathogen in aquatic animals and a threat to human health worldwide. This study investigated the prevalence, antimicrobial resistance, antimicrobial resistance genes (ARGs), and biofilm formation of V. parahaemolyticus strains isolated from fish mariculture environments in Cat Ba Island, Vietnam.<br><br>METHODS: In total, 150 rearing water samples were collected from 10 fish mariculture farms in winter and summer. A polymerase chain reaction assay was used to identify V. parahaemolyticus, its virulence factors, and ARGs. The antimicrobial resistance patterns and biofilm formation ability of V. parahaemolyticus strains were investigated using the disk diffusion test and a microtiter plate-based crystal violet method, respectively.<br><br>RESULTS: Thirty-seven V. parahaemolyticus isolates were recovered from 150 samples. The frequencies of the tdh and trh genes among V. parahaemolyticus isolates were 8.1% and 21.6%, respectively. More than 90% of isolates were susceptible to ceftazidime, cefotaxime, and chloramphenicol, but over 72% were resistant to ampicillin, tetracycline, and erythromycin. Furthermore, 67.57% of isolates exhibited multidrug resistance. The presence of ARGs related to gentamicin (aac(3)-IV), tetracycline (tetA) and ciprofloxacin (qnrA) in V. parahaemolyticus isolates was identified. Conversely, no ARGs related to ampicillin or erythromycin resistance were detected. Biofilm formation capacity was detected in significantly more multidrug-resistant isolates (64.9%) than non-multidrug-resistant isolates (18.9%).<br><br>CONCLUSION: Mariculture environments are a potential source of antibiotic-resistant V. parahaemolyticus and a hotspot for virulence genes and ARGs diffusing to aquatic environments. Thus, the prevention of antibiotic-resistant foodborne vibriosis in aquatic animals and humans requires continuous monitoring.}, }
@article {pmid38480832, year = {2024}, author = {Mahdiani, H and Yazdani, F and Khoramipour, M and Valizadeh, V and Bakhshandeh, H and Dinarvand, R}, title = {Preparation and Physicochemical Characterization of Hyaluronic Acid-Lysine Nanogels Containing Serratiopeptidase to Control Biofilm Formation.}, journal = {Scientific reports}, volume = {14}, number = {1}, pages = {6111}, pmid = {38480832}, issn = {2045-2322}, mesh = {Nanogels/chemistry ; *Hyaluronic Acid/chemistry ; *Lysine/pharmacology ; Staphylococcus aureus/physiology ; Peptide Hydrolases/pharmacology ; Anti-Bacterial Agents/pharmacology ; Biofilms ; *Polyethylene Glycols ; *Polyethyleneimine ; }, abstract = {Remarkable resistance of bacterial biofilms to high doses of antimicrobials and antibiotics is one of their main challenges. Encapsulation of proteolytic enzymes is one of the suggested strategies to tackle this problem. In this regard, the antibacterial and anti-biofilm activity of biocompatible hyaluronic acid- Lysine nanogels containing serratiopeptidase (SRP-loaded HA-Lys nanogel) was assessed against P. aeruginosa and S. aureus strains. SRP-loaded HA-Lys nanogel was prepared using dropping method and optimized by Box-Behnken experimental design. These formulations were studied for physical characterization, release profile, stability, bioactivity, and anti-biofilm effects. The particle size, polydispersity index (PDI), and surface charge were measured by Zetasizer Nano ZS. The average particle size and zeta potential of the optimum sample were 156 nm and -14.1 mV, respectively. SRP release showed an initial burst followed by sustained release and the highest release was around 77%. Enzyme biological activity data revealed the higher efficiency of free SRP compared to SRP-loaded HA-Lys nanogel. The time-kill assay showed that both forms of SRP-loaded HA-Lys nanogel and blank HA-Lys nanogel showed significant antimicrobial activity against examined bacteria in comparison to the free enzyme. The obtained results demonstrated improved anti-biofilm efficacy and down regulation of tested biofilm genes for both SRP-loaded HA-Lys nanogel 100% and blank HA-Lys nanogel 100% compared to SRP 100%.}, }
@article {pmid38480540, year = {2024}, author = {Koul, K and Jawanda, IK and Soni, T and Singh, P and Sharma, D and Kumari, S}, title = {Quantum dots: a next generation approach for pathogenic microbial biofilm inhibition; mechanistic insights, existing challenges, and future potential.}, journal = {Archives of microbiology}, volume = {206}, number = {4}, pages = {158}, pmid = {38480540}, issn = {1432-072X}, mesh = {*Quantum Dots/chemistry ; Anti-Bacterial Agents/pharmacology/chemistry ; Biofilms ; *Nanostructures ; Carbon ; }, abstract = {Quantum Dots (QDs) have emerged as versatile nanomaterials with origins spanning organic, inorganic, and natural sources, revolutionizing various biomedical applications, particularly in combating pathogenic biofilm formation. Biofilms, complex structures formed by microbial communities enveloped in exopolysaccharide matrices, pose formidable challenges to traditional antibiotics due to their high tolerance and resistance, exacerbating inefficacy issues in antibiotic treatments. QDs offer a promising solution, employing physical mechanisms like photothermal or photodynamic therapy to disrupt biofilms. Their efficacy is noteworthy, with lower susceptibility to resistance development and broad-spectrum action as compared to conventional antibiotic methods. The stability and durability of QDs ensure sustained biofilm activity, even in challenging environmental conditions. This comprehensive review delves into the synthesis, properties, and applications of Carbon Quantum Dots (CQDs), most widely used QDs, showcasing groundbreaking developments that position these nanomaterials at the forefront of cutting-edge research and innovation. These nanomaterials exhibit multifaceted mechanisms, disrupting cell walls and membranes, generating reactive oxygen species (ROS), and binding to nucleic materials, effectively inhibiting microbial proliferation. This opens transformative possibilities for healthcare interventions by providing insights into biofilm dynamics. However, challenges in size control necessitate ongoing research to refine fabrication techniques, ensure defect-free surfaces, and optimize biological activity. QDs emerge as microscopic yet potent tools, promising to contribute to a brighter future where quantum wonders shape innovative solutions to persistently challenging issues posed by pathogenic biofilms. Henceforth, this review aims to explore QDs as potential agents for inhibiting pathogenic microbial biofilms, elucidating the underlying mechanisms, addressing the current challenges, and highlighting their promising future potential.}, }
@article {pmid38478426, year = {2024}, author = {Higazy, D and Pham, AD and van Hasselt, C and Høiby, N and Jelsbak, L and Moser, C and Ciofu, O}, title = {In vivo evolution of antimicrobial resistance in a biofilm model of Pseudomonas aeruginosa lung infection.}, journal = {The ISME journal}, volume = {18}, number = {1}, pages = {}, pmid = {38478426}, issn = {1751-7370}, support = {//Egyptian Ministry of Higher Education/ ; }, mesh = {Mice ; Animals ; *Anti-Bacterial Agents/pharmacology ; Pseudomonas aeruginosa ; Microbial Sensitivity Tests ; Drug Resistance, Bacterial ; Ciprofloxacin/pharmacology ; *Pseudomonas Infections/drug therapy/microbiology ; Biofilms ; Lung ; }, abstract = {The evolution of antimicrobial resistance (AMR) in biofilms has been repeatedly studied by experimental evolution in vitro, but rarely in vivo. The complex microenvironment at the infection site imposes selective pressures on the bacterial biofilms, potentially influencing the development of AMR. We report here the development of AMR in an in vivo mouse model of Pseudomonas aeruginosa biofilm lung infection. The P. aeruginosa embedded in seaweed alginate beads underwent four successive lung infection passages with or without ciprofloxacin (CIP) exposure. The development of CIP resistance was assessed at each passage by population analysis of the bacterial populations recovered from the lungs of CIP-treated and control mice, with subsequent whole-genome sequencing of selected isolates. As inflammation plays a crucial role in shaping the microenvironment at the infection site, its impact was explored through the measurement of cytokine levels in the lung homogenate. A rapid development of AMR was observed starting from the second passage in the CIP-treated mice. Genetic analysis revealed mutations in nfxB, efflux pumps (mexZ), and two-component systems (parS) contribution to CIP resistance. The control group isolates exhibited mutations in the dipA gene, likely associated with biofilm dispersion. In the initial two passages, the CIP-treated group exhibited an elevated inflammatory response compared to the control group. This increase may potentially contribute to the release of mutagenic reactive oxygen species and the development of AMR. In conclusion, this study illustrates the complex relationship between infection, antibiotic treatment, and immune response.}, }
@article {pmid38477452, year = {2024}, author = {Luo, Z and Lu, R and Shi, T and Ruan, Z and Wang, W and Guo, Z and Zhan, Z and Ma, Y and Lian, X and Ding, C and Chen, Y}, title = {Enhanced Bacterial Cuproptosis-Like Death via Reversal of Hypoxia Microenvironment for Biofilm Infection Treatment.}, journal = {Advanced science (Weinheim, Baden-Wurttemberg, Germany)}, volume = {11}, number = {19}, pages = {e2308850}, pmid = {38477452}, issn = {2198-3844}, support = {81974340//National Natural Science Foundation of China/ ; 82172455//National Natural Science Foundation of China/ ; YG2021ZD22//Interdisciplinary Program of Shanghai Jiao Tong University/ ; SHDC12021117//Shanghai Shenkang Hospital Development Center Clinical Innovation Project/ ; 2023M732289//China Postdoctoral Science Foundation/ ; DWLL-2023-0527//Animal Welfare Ethics Committee of Shanghai Sixth People's Hospital/ ; 22S31900200//Shanghai Science and Technology Innovation Action Plan Program/ ; }, mesh = {*Biofilms/drug effects/growth &amp; development ; Animals ; *Copper/metabolism ; Mice ; Oxides/pharmacology ; Manganese Compounds ; Disease Models, Animal ; Hypoxia/metabolism ; }, abstract = {A recently emerging cell death pathway, known as copper-induced cell death, has demonstrated significant potential for treating infections. Existing research suggests that cells utilizing aerobic respiration, as opposed to those reliant on glycolysis, exhibit greater sensitivity to copper-induced death. Herein, a MnO2-loaded copper metal-organic frameworks platform is developed denoted as MCM, to enhance bacterial cuproptosis-like death via the remodeling of bacterial respiratory metabolism. The reversal of hypoxic microenvironments induced a cascade of responses, encompassing the reactivation of suppressed immune responses and the promotion of osteogenesis and angiogenesis. Initially, MCM catalyzed O2 production, alleviating hypoxia within the biofilm and inducing a transition in bacterial respiration mode from glycolysis to aerobic respiration. Subsequently, the sensitized bacteria, characterized by enhanced tricarboxylic acid cycle activity, underwent cuproptosis-like death owing to increased copper concentrations and aggregated intracellular dihydrolipoamide S-acetyltransferase (DLAT). The disruption of hypoxia also stimulated suppressed dendritic cells and macrophages, thereby strengthening their antimicrobial activity through chemotaxis and phagocytosis. Moreover, the nutritional effects of copper elements, coupled with hypoxia alleviation, synergistically facilitated the regeneration of bones and blood vessels. Overall, reshaping the infection microenvironment to enhance cuproptosis-like cell death presents a promising avenue for eradicating biofilms.}, }
@article {pmid38477236, year = {2024}, author = {Shi, Y and Wen, T and Zhao, F and Hu, J}, title = {Bacteriostasis of nisin against planktonic and biofilm bacteria: Its mechanism and application.}, journal = {Journal of food science}, volume = {89}, number = {4}, pages = {1894-1916}, doi = {10.1111/1750-3841.17001}, pmid = {38477236}, issn = {1750-3841}, support = {31801651//National Natural Science Foundation of China/ ; JJKH20241308CY//The scientific research project of the Education Department of Jilin Province/ ; }, mesh = {*Nisin/pharmacology ; Plankton ; Microbial Sensitivity Tests ; Anti-Bacterial Agents/pharmacology ; Biofilms ; Bacteria ; }, abstract = {Food safety incidents caused by bacterial contamination have always been one of the public safety issues of social concern. Planktonic cells, viable but non-culturable (VBNC) cells, and biofilm cells of bacteria can coexist in food or food processing, posing more serious challenges to public health and safety by increasing bacterial survival and difficulty in detection. As a non-toxic, no side effect, and highly effective bacteriostatic substance, nisin has received wide attention from researchers. In this review, we summarized the species and biosynthesis of nisin, the effects of nisin alone or in combination with other treatments on planktonic and biofilm cells, and its applications in the fields of food, feed, and medicine by consulting numerous studies. Meanwhile, the mechanism of nisin on planktonic and biofilm cells was proposed based on existing researches. Nisin not only has antibacterial activity against most G[+] bacteria but also exhibits a bacteriostatic effect on G[-] bacteria when combined with other antibacterial treatments. In addition to planktonic cells, nisin also has significant effects on bacterial cells in biofilms by changing the thickness, density, and composition of biofilms. Based on the three action processes of nisin on biofilms, we summarized the changes of bacteria in biofilms, including the causes of bacterial death and the formation of the VBNC state. We consider that research on the relationship between nisin and VBNC state should be strengthened.}, }
@article {pmid38475926, year = {2024}, author = {Suarez, C and Rosenqvist, T and Dimitrova, I and Sedlacek, CJ and Modin, O and Paul, CJ and Hermansson, M and Persson, F}, title = {Biofilm colonization and succession in a full-scale partial nitritation-anammox moving bed biofilm reactor.}, journal = {Microbiome}, volume = {12}, number = {1}, pages = {51}, pmid = {38475926}, issn = {2049-2618}, support = {2018-01423//Svenska Forskningsr&#xe5;det Formas/ ; 2019-00432//Svenska Forskningsr&#xe5;det Formas/ ; 2019-00432//Svenska Forskningsr&#xe5;det Formas/ ; 2018-01423//Svenska Forskningsr&#xe5;det Formas/ ; 2020-01905//Svenska Forskningsr&#xe5;det Formas/ ; ZK74//Austrian Science Fund/ ; }, mesh = {*Ammonia ; *Anaerobic Ammonia Oxidation ; Phylogeny ; Sewage/microbiology ; Bacteria ; Bioreactors/microbiology ; Nitrogen ; Biofilms ; Oxidation-Reduction ; }, abstract = {BACKGROUND: Partial nitritation-anammox (PNA) is a biological nitrogen removal process commonly used in wastewater treatment plants for the treatment of warm and nitrogen-rich sludge liquor from anaerobic digestion, often referred to as sidestream wastewater. In these systems, biofilms are frequently used to retain biomass with aerobic ammonia-oxidizing bacteria (AOB) and anammox bacteria, which together convert ammonium to nitrogen gas. Little is known about how these biofilm communities develop, and whether knowledge about the assembly of biofilms in natural communities can be applied to PNA biofilms.<br><br>RESULTS: We followed the start-up of a full-scale PNA moving bed biofilm reactor for 175 days using shotgun metagenomics. Environmental filtering likely restricted initial biofilm colonization, resulting in low phylogenetic diversity, with the initial microbial community comprised mainly of Proteobacteria. Facilitative priority effects allowed further biofilm colonization, with the growth of initial aerobic colonizers promoting the arrival and growth of anaerobic taxa like methanogens and anammox bacteria. Among the early colonizers were known 'oligotrophic' ammonia oxidizers including comammox Nitrospira and Nitrosomonas cluster 6a AOB. Increasing the nitrogen load in the bioreactor allowed colonization by 'copiotrophic' Nitrosomonas cluster 7 AOB and resulted in the exclusion of the initial ammonia- and nitrite oxidizers.<br><br>CONCLUSIONS: We show that complex dynamic processes occur in PNA microbial communities before a stable bioreactor process is achieved. The results of this study not only contribute to our knowledge about biofilm assembly and PNA bioreactor start-up but could also help guide strategies for the successful implementation of PNA bioreactors. Video Abstract.}, }
@article {pmid38475877, year = {2024}, author = {Lou, Z and Dong, J and Tao, H and Tan, Y and Wang, H}, title = {Regulation and mechanism of organic selenium on quorum sensing, biofilm, and antioxidant effects of Lactobacillus paracasei.}, journal = {Cell biochemistry and function}, volume = {42}, number = {2}, pages = {e3975}, doi = {10.1002/cbf.3975}, pmid = {38475877}, issn = {1099-0844}, support = {JUFSTR20180204//National First-class Discipline Program of Food Science and Technology/ ; }, mesh = {Quorum Sensing ; *Lacticaseibacillus paracasei ; Antioxidants/pharmacology ; *Selenium/pharmacology ; Molecular Docking Simulation ; Anti-Bacterial Agents/chemistry/metabolism/pharmacology ; Biofilms ; }, abstract = {Different organic compounds can have varying degrees of impact on the activity of Lactobacillus paracasei. The study focused on the impact and action mechanism of different organic selenium products on the bioactivity of two strains of L. paracasei. The growth, antioxidant activity, extracellular polysaccharide secretion, quorum sensing (QS), and biofilm formation of the strains before and after the addition of organic selenium crude products and three organic selenium standard were evaluated. The results showed that the addition of crude organic selenium promoted the various activities of the strain. l-selenocysteine had the strongest regulatory effect, with maximum GIM1.80 biofilm formation when it reached a critical concentration of 0.4 μg/mL; l-selenomethionine resulted in the highest activity of the signal molecule Auto inducer-2 of GDMCC1.155, when it reached a critical