@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},
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},
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 = {},
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, anti-biofilm 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 5µL/mL, and a biofilm eradication activity of 74.86% at a concentration of 2.5µL/mL. This EO was able to inhibit P. aeruginosa twitching motility by 100% at a concentration of 2.5µL/mL. Pyocyanin was inhibited by 99.33%, at a concentration of 1.25µL/mL. Rhamnolipids were significantly inhibited by 63.33% in the presence of Thyme EO at a concentration of 1.25µL/mL after 24h of incubation. Molecular docking showed that carvacrol and thymol can bind to the three QS 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. Keywords antibiofilm, thymol, essential oil, Pseudomonas aeruginosa, pyocyanin, rhamnolipids, in silico study.},
}
@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 = {},
doi = {10.3390/microorganisms12122523},
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 = {},
doi = {10.3390/microorganisms12122496},
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 = {},
doi = {10.3390/microorganisms12122478},
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 = {},
doi = {10.3390/ph17121719},
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 = {},
doi = {10.3390/ph17121673},
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 = {},
doi = {10.3390/ph17121653},
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 = {},
doi = {10.3390/ph17121613},
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 = {},
doi = {10.3390/molecules29245945},
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 = {},
doi = {10.3390/ijms252413378},
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 = {},
doi = {10.3390/medicina60121959},
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 = {},
doi = {10.3390/foods13244104},
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 = {},
doi = {10.3390/foods13244002},
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 = {},
doi = {10.3390/antibiotics13121232},
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 = {},
doi = {10.3390/antibiotics13121228},
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 = {},
doi = {10.3390/antibiotics13121227},
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 = {},
doi = {10.3390/antibiotics13121148},
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 = {},
doi = {10.3390/antibiotics13121132},
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 = {},
doi = {10.3390/antibiotics13121113},
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 = {},
number = {},
pages = {},
doi = {10.1021/acsnano.4c15730},
pmid = {39764613},
issn = {1936-086X},
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},
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 = {},
doi = {10.1101/2024.12.19.629378},
pmid = {39764008},
issn = {2692-8205},
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 = {},
doi = {10.1101/2024.12.17.628960},
pmid = {39763852},
issn = {2692-8205},
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 a ttachment m utants (iam) and s urface a ttachment d efective (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 = {},
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},
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 = {},
number = {},
pages = {1-14},
doi = {10.1080/08927014.2024.2446927},
pmid = {39757571},
issn = {1029-2454},
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 Kuamr, A},
title = {Biofilm Battle: New transformative tactics to tackle the bacterial biofilm infections.},
journal = {Microbial pathogenesis},
volume = {},
number = {},
pages = {107277},
doi = {10.1016/j.micpath.2025.107277},
pmid = {39756524},
issn = {1096-1208},
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 = {},
number = {},
pages = {},
doi = {10.1093/femsle/fnae116},
pmid = {39756377},
issn = {1574-6968},
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 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. Contrarily, EE-L inhibited S. Typhimurium at 12.5-50% and P. aeruginosa at 25-50% concentration, 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, and contrarily, 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 minimising 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 = {},
number = {},
pages = {},
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)/ ; TMCG-3_213801//Schweizerischer Nationalfonds zur F&#xf6;rderung der Wissenschaftlichen Forschung (Swiss National Science Foundation)/ ; 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)/ ; 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)/ ; 716734//EC | EU Framework Programme for Research and Innovation H2020 | H2020 Priority Excellent Science | H2020 European Research Council (H2020 Excellent Science - European Research Council)/ ; 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)/ ; IMPRS-Mic//Max-Planck-Gesellschaft (Max Planck Society)/ ; IMPRS-Mic//Max-Planck-Gesellschaft (Max Planck Society)/ ; },
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 = {2024},
author = {Kim, M-J and Mitchell, AP},
title = {Strain-limited biofilm regulation through the Brg1-Rme1 circuit in Candida albicans.},
journal = {mSphere},
volume = {},
number = {},
pages = {e0098024},
doi = {10.1128/msphere.00980-24},
pmid = {39745385},
issn = {2379-5042},
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 = {2024},
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 = {},
number = {},
pages = {e0037924},
doi = {10.1128/jb.00379-24},
pmid = {39745371},
issn = {1098-5530},
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 = {},
number = {},
pages = {1-18},
doi = {10.1080/08927014.2024.2446928},
pmid = {39745063},
issn = {1029-2454},
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 = {},
number = {},
pages = {1-10},
doi = {10.1080/08927014.2024.2446932},
pmid = {39745056},
issn = {1029-2454},
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 = {2024},
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 = {},
number = {},
pages = {144048},
doi = {10.1016/j.chemosphere.2024.144048},
pmid = {39743153},
issn = {1879-1298},
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 = {},
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 = {2024},
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},
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},
doi = {10.1002/imt2.244},
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},
doi = {10.4103/jisp.jisp_428_23},
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},
doi = {10.1021/acsomega.4c08702},
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 = {2024},
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},
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 = {2024},
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},
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 = {2024},
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},
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 = {2024},
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 = {},
number = {},
pages = {125144},
doi = {10.1016/j.ijpharm.2024.125144},
pmid = {39734057},
issn = {1873-3476},
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 = {2024},
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 = {},
number = {},
pages = {},
doi = {10.1093/femsle/fnae115},
pmid = {39732619},
issn = {1574-6968},
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 (NCI). 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 = {2024},
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},
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 = {2024},
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 = {},
number = {},
pages = {125112},
doi = {10.1016/j.ijpharm.2024.125112},
pmid = {39732217},
issn = {1873-3476},
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 = {2024},
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},
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 = {2024},
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},
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 = {2024},
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 = {},
number = {},
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/ ; },
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 = {2024},
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 = {},
number = {},
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/ ; },
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, VV and SirigiReddy, B and Lomada, D and Reddy, MC},
title = {Synthesis and Characterization of Silver and Zinc Nanoparticles from Vitex altissima: Comparative Analysis of Anti-oxidant, Anti-inflammatory, Anti-bacterial 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-XRD, FE-SEM, FTIR, TEM, DLS, and Zeta potential. Synthesized silver and zinc nanoparticles were screened for anti-oxidant, anti-inflammatory, anti-bacterial, and anti-biofilm activities. AgNPs exhibited moderate anti-oxidant activities compared to ZnNPs which were studied using DPPH and ABTS assays. The anti-inflammatory effect was assessed using membrane stabilization and human red blood cell methods. Furthermore, both nanoparticles AgNPs and ZnNPs exhibited antibiofilm activity against four MDR bacterial strains Escherichia coli, Staphylococcus aureus, Klebsiella pneumonia and Pseudomonas aeruginosa. Synthesized nanoparticles show anti-bacterial activity. Our data suggest that silver nanoparticles exhibited moderate activity compared to ZnNPs. These nanoparticles could act as potential anti-oxidant, anti-inflammatory, anti-bacterial and anti-inflammatory 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 = {2024},
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},
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 = {2024},
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},
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 = {2024},
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 = {},
number = {},
pages = {107241},
doi = {10.1016/j.micpath.2024.107241},
pmid = {39716652},
issn = {1096-1208},
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 0.19-0.78 mg/mL and in the study of the anti-biofilm effect of Fe3O4NPs@UA, it caused a 68-75% 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 = {},
doi = {10.21203/rs.3.rs-5494070/v1},
pmid = {39711551},
issn = {2693-5015},
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 = {2024},
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 = {},
number = {},
pages = {},
doi = {10.1016/j.actbio.2024.12.042},
pmid = {39710222},
issn = {1878-7568},
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 = {},
number = {},
pages = {},
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 = {2024},
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},
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 = {2024},
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},
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 = {2024},
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},
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 = {2024},
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},
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 = {2024},
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 = {},
number = {},
pages = {131999},
doi = {10.1016/j.biortech.2024.131999},
pmid = {39706307},
issn = {1873-2976},
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 = {},
number = {},
pages = {108096},
doi = {10.1016/j.jbc.2024.108096},
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 P. aeruginosa infections. Our findings also underscore the impact of environmental factors on 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 key to understanding their roles in bacterial biofilms. Furthermore, the study highlights distinct differences between Fap and E. 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 bio-nanomaterials or protective coatings.},
}
@article {pmid39705953,
year = {2024},
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},
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 = {2024},
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},
doi = {10.1016/j.biomaterials.2024.123015},
pmid = {39705926},
issn = {1878-5905},
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 = {2024},
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},
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 = {2024},
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 = {},
number = {},
pages = {e0241524},
doi = {10.1128/spectrum.02415-24},
pmid = {39705014},
issn = {2165-0497},
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},
doi = {10.14744/eej.2024.75983},
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 = {2024},
author = {Kaur, N and De, M},
title = {Shape and Size Dependent Antimicrobial and Anti-biofilm Properties of Functionalized MoS2.},
journal = {ACS infectious diseases},
volume = {},
number = {},
pages = {},
doi = {10.1021/acsinfecdis.4c00860},
pmid = {39703182},
issn = {2373-8227},
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 = {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 = {2024},
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},
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 = {2024},
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},
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},
doi = {10.3389/froh.2024.1483078},
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},
doi = {10.1080/19490976.2024.2443107},
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 = {*Berberine/pharmacology ; *Biofilms/drug effects/growth &amp; development ; *Antifungal Agents/pharmacology ; *Drug Resistance, Fungal ; *Fungi/drug effects ; Humans ; Virulence/drug effects ; Animals ; Mycoses/drug therapy/microbiology ; Microbial Sensitivity Tests ; Virulence Factors ; },
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 = {2024},
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 = {},
number = {},
pages = {1-6},
doi = {10.1080/10520295.2024.2439447},
pmid = {39688594},
issn = {1473-7760},
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 = {2024},
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 = {},
number = {},
pages = {e0328324},
doi = {10.1128/mbio.03283-24},
pmid = {39688394},
issn = {2150-7511},
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},
doi = {10.1016/j.btre.2024.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 = {},
doi = {10.3390/ijms252312808},
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 = {},
doi = {10.3390/molecules29235694},
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 = {},
doi = {10.3390/foods13233841},
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 = {},
doi = {10.3390/foods13233834},
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 = {},
doi = {10.3390/foods13233822},
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},
doi = {10.1073/pnas.2417323121},
pmid = {39680756},
issn = {1091-6490},
support = {5R01 AI139011//HHS | National Institutes of Health (NIH)/ ; R01 AI057576/AI/NIAID NIH HHS/United States ; startup funds//Brandeis University (BU)/ ; fellowship//Real Colegio Complutense Fellowship/ ; },
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},
doi = {10.1167/tvst.13.12.25},
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 = {},
doi = {10.1101/2024.12.06.627279},
pmid = {39677627},
issn = {2692-8205},
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 = {},
number = {},
pages = {},
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 = {2024},
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 = {},
number = {},
pages = {107232},
doi = {10.1016/j.micpath.2024.107232},
pmid = {39675440},
issn = {1096-1208},
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%) and 31/35 (88.6%) Candida isolates, respectively. Up to 25/35 (71.4%) of the Candida isolates exhibited biofilm formation, whereas esterase activity was demonstrated in 23/35 (65.7%) of the Candida isolates. Fewer isolates (21/35, 60%) produced hemolysin, and coagulase production was the least common virulence activity detected in 18/35 (51.4%) 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 = {2024},
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 = {},
number = {},
pages = {120602},
doi = {10.1016/j.envres.2024.120602},
pmid = {39674248},
issn = {1096-0953},
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 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, the functional properties, and the MBBR application potentials.},
}
@article {pmid39674004,
year = {2024},
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},
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 {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 {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},
doi = {10.1371/journal.pone.0315755},
pmid = {39656705},
issn = {1932-6203},
abstract = {[This corrects the article DOI: 10.1371/journal.pone.0257449.].},
}
@article {pmid39671748,
year = {2024},
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},
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},
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 = {2024},
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 = {},
number = {},
pages = {107219},
doi = {10.1016/j.micpath.2024.107219},
pmid = {39667637},
issn = {1096-1208},
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 = {2024},
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 = {},
number = {},
pages = {131959},
doi = {10.1016/j.biortech.2024.131959},
pmid = {39667627},
issn = {1873-2976},
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 = {2024},
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},
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 = {2024},
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},
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 = {2024},
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 = {},
number = {},
pages = {e0074324},
doi = {10.1128/msphere.00743-24},
pmid = {39660862},
issn = {2379-5042},
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 = {2024},
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 = {},
number = {},
pages = {107208},
doi = {10.1016/j.micpath.2024.107208},
pmid = {39657894},
issn = {1096-1208},
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. Their antibacterial and anti-biofilm activities are evaluated, and their potential mechanisms of action are preliminarily explored. The results demonstrated that DHA-CS NPs exhibited a minimum inhibitory concentration (MIC) of of 15 μg/mL, and a minimum bactericidal concentration (MBC) of 30 μg/mL. At 15 μg/mL, DHA-CS NPs significantly inhibited MRSA biofilm formation (P < 0.001),while at 7.5 μg/mL, they disperse 67.4 ± 3.77% of 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, reveal that DHA-CS NPs inhibit the synthesis of extracellular polymeric substances (EPS), suppress the release of extracellular DNA (eDNA), and downregulate 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 developing novel antibiofilm therapies.},
}
@article {pmid39657876,
year = {2024},
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 = {},
number = {},
pages = {138579},
doi = {10.1016/j.ijbiomac.2024.138579},
pmid = {39657876},
issn = {1879-0003},
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 = {2024},
author = {Wei, Y and Xia, W and Qian, Y and Rong, C and Ye, M and Yujie, C 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 = {},
number = {},
pages = {131963},
doi = {10.1016/j.biortech.2024.131963},
pmid = {39653175},
issn = {1873-2976},
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 = {},
number = {},
pages = {},
doi = {10.1021/jacs.4c12945},
pmid = {39651958},
issn = {1520-5126},
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 = {2024},
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 = {},
number = {},
pages = {125489},
doi = {10.1016/j.envpol.2024.125489},
pmid = {39647771},
issn = {1873-6424},
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 = {2024},
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 = {},
number = {},
pages = {106654},
doi = {10.1016/j.jsbmb.2024.106654},
pmid = {39645169},
issn = {1879-1220},
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 = {2024},
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},
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 = {},
number = {},
pages = {1-16},
doi = {10.1080/08927014.2024.2435027},
pmid = {39639551},
issn = {1029-2454},
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 = {2024},
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 = {},
number = {},
pages = {},
doi = {10.1111/1348-0421.13189},
pmid = {39639432},
issn = {1348-0421},
support = {//The study was supported by University of Kurdistan, Iran./ ; },
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 = {2024},
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 = {},
number = {},
pages = {},
doi = {10.1016/j.jhin.2024.06.024},
pmid = {39638047},
issn = {1532-2939},
}
@article {pmid39638004,
year = {2024},
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 = {},
number = {},
pages = {131941},
doi = {10.1016/j.biortech.2024.131941},
pmid = {39638004},
issn = {1873-2976},
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 = {},
number = {},
pages = {},
doi = {10.1016/j.chembiol.2024.11.005},
pmid = {39637855},
issn = {2451-9448},
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 = {2024},
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 = {},
number = {},
pages = {e0324224},
doi = {10.1128/mbio.03242-24},
pmid = {39636114},
issn = {2150-7511},
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 = {},
number = {},
pages = {},
doi = {10.1021/acsami.4c17855},
pmid = {39635909},
issn = {1944-8252},
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 = {},
number = {},
pages = {},
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/ ; },
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 = {2024},
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 = {},
number = {},
pages = {131925},
doi = {10.1016/j.biortech.2024.131925},
pmid = {39631547},
issn = {1873-2976},
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 = {2024},
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},
doi = {10.1016/j.ultsonch.2024.107100},
pmid = {39631356},
issn = {1873-2828},
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 = {2024},
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 = {},
number = {},
pages = {220345241290147},
doi = {10.1177/00220345241290147},
pmid = {39629932},
issn = {1544-0591},
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 = {2024},
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 = {},
number = {},
pages = {},
doi = {10.1093/jac/dkae424},
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/ ; },
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 = {2024},
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 = {},
number = {},
pages = {e0105024},
doi = {10.1128/spectrum.01050-24},
pmid = {39625293},
issn = {2165-0497},
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 = {2024},
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 = {},
number = {},
pages = {131918},
doi = {10.1016/j.biortech.2024.131918},
pmid = {39622419},
issn = {1873-2976},
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, A 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},
doi = {10.1371/journal.ppat.1012750},
pmid = {39621768},
issn = {1553-7374},
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 = {2024},
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},
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 = {},
number = {},
pages = {143854},
doi = {10.1016/j.chemosphere.2024.143854},
pmid = {39615850},
issn = {1879-1298},
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 hours) 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 = {2024},
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 = {},
number = {},
pages = {131910},
doi = {10.1016/j.biortech.2024.131910},
pmid = {39615760},
issn = {1873-2976},
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 = {2024},
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},
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},
doi = {10.1111/1751-7915.70040},
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 = {2024},
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 = {},
number = {},
pages = {e0231324},
doi = {10.1128/spectrum.02313-24},
pmid = {39612475},
issn = {2165-0497},
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 = {2024},
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 = {},
number = {},
pages = {e0198024},
doi = {10.1128/spectrum.01980-24},
pmid = {39612218},
issn = {2165-0497},
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 = {2024},
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 = {},
number = {},
pages = {},
doi = {10.1016/j.urology.2024.11.049},
pmid = {39608581},
issn = {1527-9995},
}
@article {pmid39608508,
year = {2024},
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 = {},
number = {},
pages = {107172},
doi = {10.1016/j.micpath.2024.107172},
pmid = {39608508},
issn = {1096-1208},
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 = {2024},
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 culture on self-settling performance and water purification capacity of microalgae biofilm.},
journal = {Environmental research},
volume = {},
number = {},
pages = {120342},
doi = {10.1016/j.envres.2024.120342},
pmid = {39608432},
issn = {1096-0953},
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},
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 = {2024},
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 = {},
number = {},
pages = {e202416577},
doi = {10.1002/anie.202416577},
pmid = {39604799},
issn = {1521-3773},
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 = {},
number = {},
pages = {},
pmid = {39604718},
issn = {1614-7499},
support = {20.19.03.012.00.00//Empresa Brasileira de Pesquisa Agropecu&#xe1;ria/ ; },
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},
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},
abstract = {Lichen substances have been firstly described in the 1870s and 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 giving access to a wild diversity of culturable microorganisms. The increasing research in lichens associated microbiome in recent years, has emphased 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,…). 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. Only two lichen metabolites, usnic acid and evernic acid, have been evaluated both as antifungal and antibacterial biofilm compounds.},
}
@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 = {2024},
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 = {},
number = {},
pages = {},
doi = {10.1111/wrr.13241},
pmid = {39600232},
issn = {1524-475X},
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 = {},
doi = {10.3390/jcm13226724},
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 = {},
doi = {10.3390/microorganisms12112309},
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 = {},
doi = {10.3390/microorganisms12112297},
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 = {},
doi = {10.3390/microorganisms12112284},
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 = {},
doi = {10.3390/microorganisms12112257},
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 = {},
doi = {10.3390/microorganisms12112237},
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 = {},
doi = {10.3390/microorganisms12112231},
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 = {},
doi = {10.3390/microorganisms12112223},
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 = {},
doi = {10.3390/microorganisms12112124},
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 = {},
doi = {10.3390/microorganisms12112115},
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 = {},
doi = {10.3390/antibiotics13111064},
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 = {},
doi = {10.3390/antibiotics13111047},
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 = {},
doi = {10.3390/antibiotics13111039},
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 = {},
doi = {10.3390/antibiotics13111014},
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 = {},
doi = {10.3390/antibiotics13111000},
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 = {},
doi = {10.3390/ijms252212222},
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 = {},
doi = {10.3390/ijms252212157},
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 = {},
doi = {10.3390/ijms252212116},
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 = {},
doi = {10.3390/ani14223290},
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 = {},
number = {},
pages = {},
doi = {10.1172/JCI183576},
pmid = {39589820},
issn = {1558-8238},
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 on its efficacy and therapeutic mechanisms is lacking. Here, we investigate whether FMX-nanozymes can treat chronic biofilm infections and compare their bioactivity to 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 NaOCl without adverse effects. FMX binds efficiently to 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 apical papilla (SCAP), 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, we show 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 = {},
number = {},
pages = {},
doi = {10.1021/acs.jafc.4c07381},
pmid = {39589428},
issn = {1520-5118},
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 = {2024},
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 = {},
number = {},
pages = {e0107124},
doi = {10.1128/aem.01071-24},
pmid = {39589111},
issn = {1098-5336},
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},
doi = {10.1080/14756366.2024.2429109},
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 = {2024},
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 = {},
number = {},
pages = {e2409200},
doi = {10.1002/advs.202409200},
pmid = {39587976},
issn = {2198-3844},
support = {JL06120001H//Joint Laboratory of Plasma Application Technology Funding/ ; R2023063//Hunan Provincial Health High-Level Talent Scientific Research Project/ ; },
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 = {2024},
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, Characterisation, and Biofilm Control using Common Disinfectants.},
journal = {The Journal of hospital infection},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.jhin.2024.11.013},
pmid = {39586542},
issn = {1532-2939},
abstract = {Hospital wastewater systems have been identified as reservoirs for antibiotic-resistant bacteria, with biofilms harbouring extended-spectrum β-lactamase (ESBL)-producing microorganisms posing significant infection risk. This study focuses on 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. 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[TM], Virkon[TM], and Clinell[TM] were performed on selected isolates. ESBL-producing bacteria (n=39 isolates) showed a high degree of resistance to β-lactams. Biofilm-forming ability ranged from non-adherent to strongly adherent and appeared to be source dependent, suggesting 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[TM] showing significant biofilm reduction against all isolates at all concentrations and contact times tested. Of the chlorine-based formulations, Optizan[TM] 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. 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 emphasises the need for rigorous and effective infection control practices.},
}
@article {pmid39586513,
year = {2024},
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 = {},
number = {},
pages = {125001},
doi = {10.1016/j.ijpharm.2024.125001},
pmid = {39586513},
issn = {1873-3476},
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 = {2024},
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 = {},
number = {},
pages = {107155},
doi = {10.1016/j.micpath.2024.107155},
pmid = {39586337},
issn = {1096-1208},
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 = {2024},
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},
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},
doi = {10.1371/journal.pbio.3002928},
pmid = {39585926},
issn = {1545-7885},
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 = {},
number = {},
pages = {104421},
doi = {10.1016/j.pdpdt.2024.104421},
pmid = {39581435},
issn = {1873-1597},
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 minutes for both irradiation methods. After 6 hours of treatment, the bactericidal effects of aPDT and antibiotics were similar, but after 32 hours, 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 = {3P01AI083211//U.S. Department of Health &amp; Human Services | NIH | National Institute of Allergy and Infectious Diseases (NIAID)/ ; F32NS126302//U.S. Department of Health &amp; Human Services | NIH | National Institute of Neurological Disorders and Stroke (NINDS)/ ; },
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 = {2024},
author = {Semeshchenko, D and Veiga, MF and Visus, M and Farinati, A and Huespe, I and , and Buttaro, MA and Slullitel, PA and , },
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 = {},
number = {},
pages = {},
doi = {10.1016/j.jhin.2024.11.012},
pmid = {39579939},
issn = {1532-2939},
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 of five antibacterial solutions and compare their efficacy in eradicating Staphylococcal biofilm embedded on a titanium surface.<br><br>METHODS: Methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus 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, chlorhexidine. Minimum biofilm eradication concentration (MBEC) values were calculated for MSSA and MRSA. After 24 hours, screw-caps were exposed 3 minutes 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 three-fold 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 ug/mL and 16000 ug/ml for povidone iodine; 64 ug/mL and 128 ug/mL for rifampicin; 10000 ug/mL and 5120 ug/mL for silver nitrate; 900 ug/mL and 900 ug/mL for copper sulphate; 16 ug/mL and 32 ug/mL for chlorhexidine. Rifampicin, copper sulphate and chlorhexidine were ineffective against MSSA and MRSA biofilm compared to 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-hour 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 = {},
number = {},
pages = {177578},
doi = {10.1016/j.scitotenv.2024.177578},
pmid = {39579902},
issn = {1879-1026},
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 = {2024},
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},
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 {pmid39577523,
year = {2024},
author = {Salim, A and Sathishkumar, P},
title = {Therapeutic efficacy of chitosan-based hybrid nanomaterials to treat microbial biofilm and their infections - A review.},
journal = {International journal of biological macromolecules},
volume = {},
number = {},
pages = {137850},
doi = {10.1016/j.ijbiomac.2024.137850},
pmid = {39577523},
issn = {1879-0003},
abstract = {Antimicrobial resistance, the biggest issue facing the global healthcare sector, quickly emerged and spread due to the frequent use of antibiotics in regular treatments. The investigation of polymer-based nanomaterials as possible antibiofilm treatment agents is prompted by the growing ineffectiveness of conventional therapeutic techniques against these resistant bacteria species. So far, several articles have been published on microbial biofilm eradication using various polymer-based nanomaterials due to their therapeutic efficacy and biocompatibility nature. Despite their potential, a comprehensive review of the chitosan-based hybrid nanomaterials to treat microbial biofilm and infections is lacking. This review provides a comprehensive investigation of the current state of therapeutic efficacy, various nanoformulations, advantages, limitations, and regulations of chitosan-based hybrid nanomaterials for biofilm treatment. Special attention is given to the application of chitosan-based nanomaterials in wound care, urinary tract infections (UTIs), and dental biofilms are discussed, highlighting their role in managing biofilm-associated complications. Researchers will be better able to comprehend and develop unique, marketable chitosan-based nanomaterials with increased activity to treat biofilm infections in near future with the aid of this review.},
}
@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 = {},
doi = {10.1101/2024.11.04.621531},
pmid = {39574716},
issn = {2692-8205},
abstract = {UNLABELLED: 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.<br><br>IMPORTANCE: For bacteria to secrete folded proteins to the environment, they have to overcome the physical barriers of an outer membrane in Gram-negative bacteria and the thick peptidoglycan layer in Gram-positive bacteria. One mechanism to do this is the use of a Type II secretion system in Gram-negative bacteria, which has a similar structure as type IV pili and is modeled to act as a piston that pumps folded proteins through the outer membrane to the environment. Clostridium perfringens , like all or most all of the clostridia, has type IV pili and, in fact, has two sets of pilus-associated genes. Here we present evidence that C. perfringens uses one set of pilus genes to secrete a biofilm associated protein and may be responsible for secreting the main biofilm protein BsaA. We show that BsaA monomers are, unlike most other biofilm matrix proteins, linked by intermolecular isopeptide bonds, enhancing the physical strength of BsaA fibers.},
}
@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 = {},
doi = {10.1101/2024.11.04.621402},
pmid = {39574578},
issn = {2692-8205},
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 = {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 = {2024},
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 = {},
number = {},
pages = {131845},
doi = {10.1016/j.biortech.2024.131845},
pmid = {39566691},
issn = {1873-2976},
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 lx), 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 = {2024},
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 = {},
number = {},
pages = {149105},
doi = {10.1016/j.gene.2024.149105},
pmid = {39566593},
issn = {1879-0038},
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 = {2024},
author = {Bamberger, MH},
title = {Editorial Comment on Indwelling Urological Devise Biofilm Composition and Characteristics in the Presence and Absence of Infection.},
journal = {Urology},
volume = {},
number = {},
pages = {},
doi = {10.1016/j.urology.2024.11.016},
pmid = {39566588},
issn = {1527-9995},
}
@article {pmid39566460,
year = {2024},
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},
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 = {2024},
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},
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 = {2024},
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 = {},
number = {},
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/ ; },
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 = {2024},
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},
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 = {2024},
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 = {},
number = {},
pages = {},
doi = {10.4269/ajtmh.24-0276},
pmid = {39561392},
issn = {1476-1645},
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 = {2024},
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 = {},
number = {},
pages = {105466},
doi = {10.1016/j.jdent.2024.105466},
pmid = {39557280},
issn = {1879-176X},
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&#x202f;+&#x202f;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 modulates 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 = {2024},
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 = {},
number = {},
pages = {131838},
doi = {10.1016/j.biortech.2024.131838},
pmid = {39557100},
issn = {1873-2976},
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 = {},
number = {},
pages = {e0304523},
doi = {10.1128/mbio.03045-23},
pmid = {39555918},
issn = {2150-7511},
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 = {},
number = {},
pages = {1-11},
doi = {10.1080/08927014.2024.2426759},
pmid = {39555709},
issn = {1029-2454},
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 = {2024},
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 = {},
number = {},
pages = {107121},
doi = {10.1016/j.micpath.2024.107121},
pmid = {39551111},
issn = {1096-1208},
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 = {2024},
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 = {},
number = {},
pages = {107124},
doi = {10.1016/j.micpath.2024.107124},
pmid = {39551108},
issn = {1096-1208},
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 = {2024},
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},
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 = {2024},
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 = {},
number = {},
pages = {},
doi = {10.1016/j.jbiotec.2024.11.007},
pmid = {39549924},
issn = {1873-4863},
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 130mg/L of hEGF, with a production efficiency of 2.71mg/L/h - surpassing the production efficiency of traditional free fermentation (1.62mg/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},
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 = {},
number = {},
pages = {},
doi = {10.1080/14712598.2024.2430623},
pmid = {39548688},
issn = {1744-7682},
}
@article {pmid39547568,
year = {2024},
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 = {},
number = {},
pages = {120362},
doi = {10.1016/j.envres.2024.120362},
pmid = {39547568},
issn = {1096-0953},
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 = {2024},
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},
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},
doi = {10.1002/wer.11150},
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},
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 = {2024},
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},
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 {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 = {},
number = {},
pages = {e0234124},
doi = {10.1128/spectrum.02341-24},
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 Applying phages to control endotracheal tube biofilm.},
journal = {Emerging microbes &amp; infections},
volume = {},
number = {},
pages = {2420737},
doi = {10.1080/22221751.2024.2420737},
pmid = {39530158},
issn = {2222-1751},
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},
doi = {10.1080/20002297.2024.2424227},
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 {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},
doi = {10.1093/femsmc/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 {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 {pmid39528199,
year = {2024},
author = {Faghani-Eskandarkolaei, P and Heli, H and Akbari, N and Koohi-Hosseinabadi, O and Aslani, FS 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 = {},
number = {},
pages = {137430},
doi = {10.1016/j.ijbiomac.2024.137430},
pmid = {39528199},
issn = {1879-0003},
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 = {2024},
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 = {},
number = {},
pages = {107105},
doi = {10.1016/j.micpath.2024.107105},
pmid = {39527987},
issn = {1096-1208},
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 = {},
number = {},
pages = {e0217124},
doi = {10.1128/mbio.02171-24},
pmid = {39526776},
issn = {2150-7511},
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},
doi = {10.1093/femsmc/xtae030},
pmid = {39524554},
issn = {2633-6685},
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},
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 = {},
doi = {10.3390/ijms252111770},
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 = {},
doi = {10.3390/ijms252111684},
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 = {},
doi = {10.3390/ijms252111675},
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 = {},
doi = {10.3390/jcm13216464},
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 = {},
doi = {10.3390/foods13213362},
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 = {},
number = {},
pages = {137302},
doi = {10.1016/j.ijbiomac.2024.137302},
pmid = {39515706},
issn = {1879-0003},
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 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 = {2024},
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 = {},
number = {},
pages = {107092},
doi = {10.1016/j.micpath.2024.107092},
pmid = {39515546},
issn = {1096-1208},
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},
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},
doi = {10.3389/fphar.2024.1487083},
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},
doi = {10.4103/ccd.ccd_106_24},
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 = {R B Brown, S 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 = {},
number = {},
pages = {100399},
doi = {10.1016/j.jfp.2024.100399},
pmid = {39510503},
issn = {1944-9097},
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 (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 24h 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 1h 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 (4000 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) 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 = {},
number = {},
pages = {177390},
doi = {10.1016/j.scitotenv.2024.177390},
pmid = {39510286},
issn = {1879-1026},
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 = {2024},
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 = {},
number = {},
pages = {1-12},
doi = {10.1080/17460913.2024.2411921},
pmid = {39508342},
issn = {1746-0921},
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 {pmid39505283,
year = {2024},
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},
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 = {2024},
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 = {},
number = {},
pages = {120294},
doi = {10.1016/j.envres.2024.120294},
pmid = {39505133},
issn = {1096-0953},
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 = {},
number = {},
pages = {107103},
doi = {10.1016/j.micpath.2024.107103},
pmid = {39505089},
issn = {1096-1208},
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 = {2024},
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},
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 = {},
number = {},
pages = {e0086824},
doi = {10.1128/msphere.00868-24},
pmid = {39503496},
issn = {2379-5042},
}
@article {pmid39503080,
year = {2024},
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},
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 = {},
number = {},
pages = {177337},
doi = {10.1016/j.scitotenv.2024.177337},
pmid = {39500459},
issn = {1879-1026},
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 = {"Bon doktoranta SD UPWr" no. N020/0001/21//the Wroc&#x142;aw University of Environmental and Life Sciences (Poland)/ ; AI154078/NH/NIH HHS/United States ; 2022/47/O/NZ7/01326//Narodowe Centrum Nauki/ ; },
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 = {},
number = {},
pages = {e0110224},
doi = {10.1128/aem.01102-24},
pmid = {39495077},
issn = {1098-5336},
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 = {},
number = {},
pages = {e0162324},
doi = {10.1128/aem.01623-24},
pmid = {39494899},
issn = {1098-5336},
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 = {},
number = {},
pages = {e0120124},
doi = {10.1128/spectrum.01201-24},
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 = {},
number = {},
pages = {1-19},
doi = {10.1080/08927014.2024.2420002},
pmid = {39494760},
issn = {1029-2454},
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 = {The study aimed to assess the effectiveness of these formulations against 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 = {2024},
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 = {},
number = {},
pages = {131741},
doi = {10.1016/j.biortech.2024.131741},
pmid = {39491739},
issn = {1873-2976},
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 Topsakal, HNH 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 = {},
number = {},
pages = {},
doi = {10.1016/j.jconrel.2024.10.071},
pmid = {39491627},
issn = {1873-4995},
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 = {},
number = {},
pages = {124865},
doi = {10.1016/j.ijpharm.2024.124865},
pmid = {39490789},
issn = {1873-3476},
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 = {},
number = {},
pages = {107068},
doi = {10.1016/j.micpath.2024.107068},
pmid = {39490595},
issn = {1096-1208},
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 an MIC of 8 &#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 = {2024},
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},
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 = {},
number = {},
pages = {105447},
doi = {10.1016/j.jdent.2024.105447},
pmid = {39489326},
issn = {1879-176X},
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 16s 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},
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 {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},
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 {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 = {},
number = {},
pages = {100394},
doi = {10.1016/j.jfp.2024.100394},
pmid = {39486481},
issn = {1944-9097},
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 multi-strain 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, which 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 {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 {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 = {},
number = {},
pages = {107373},
doi = {10.1016/j.ijantimicag.2024.107373},
pmid = {39486468},
issn = {1872-7913},
abstract = {Hypervirulent Klebsiella pneumoniae (hvKp) poses a serious public health threat. Gas gangrene caused by hvKp was rarely reported, potentially resulting in a poor prognosis. In this study, we described the case of a hospitalized patient with gas gangrene and sepsis by hvKP. The 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 (SNPs<10) and belonging to ST412/K57. The minimum inhibitory concentration and minimum bactericidal concentration under biofilm values of meropenem in KPLSN and KPLSX were significantly higher than planktonic state (>128 mg/L versus 0.25 mg/L, P<0.0001). These two strains had high biofilm formation ability, and fluorescence staining experiments results showed that they were not easily killed by meropenem in the biofilm state. KPLSN and KPLSX showed high capsular production and were confirmed with high virulence through experiments with the Galleria mellonella and BALB/c mice abdominal infection model. The persistent symptoms may be due to enhanced biofilm and capsule formation. Global ST412 strains phylogenetic analysis showed their evolution towards higher virulence and resistance. It emphasizes the critical need for judicious antibiotic use and novel therapeutic approaches to combat special infections caused by these pathogens.},
}
@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 {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 {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 {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 effect and biofilm eradication.},
journal = {International journal of biological macromolecules},
volume = {},
number = {},
pages = {137080},
doi = {10.1016/j.ijbiomac.2024.137080},
pmid = {39481715},
issn = {1879-0003},
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 of 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 = {},
number = {},
pages = {107085},
doi = {10.1016/j.micpath.2024.107085},
pmid = {39481691},
issn = {1096-1208},
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 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 = {2024},
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},
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 {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 {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 {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 {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 {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 = {},
number = {},
pages = {},
pmid = {39480631},
issn = {1678-4405},
support = {2017/07339-4//FAPESP/ ; 30201*52//FUNDEP/ ; },
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 {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 = {},
number = {},
pages = {125216},
doi = {10.1016/j.envpol.2024.125216},
pmid = {39477005},
issn = {1873-6424},
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 = {2024},
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},
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 = {},
number = {},
pages = {e0216424},
doi = {10.1128/mbio.02164-24},
pmid = {39475232},
issn = {2150-7511},
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 = {2024},
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 = {},
number = {},
pages = {131719},
doi = {10.1016/j.biortech.2024.131719},
pmid = {39471904},
issn = {1873-2976},
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},
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 = {2024},
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},
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 = {},
number = {},
pages = {e0168324},
doi = {10.1128/spectrum.01683-24},
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 = {},
number = {},
pages = {e0020224},
doi = {10.1128/mra.00202-24},
pmid = {39470240},
issn = {2576-098X},
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 = {},
number = {},
pages = {},
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/ ; },
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 = {},
doi = {10.1101/2024.10.14.618124},
pmid = {39464101},
issn = {2692-8205},
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 Δ staB 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 (Δ staA and Δ mltA) 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 = {},
doi = {10.1101/2024.10.13.618105},
pmid = {39463994},
issn = {2692-8205},
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 = {2024},
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 = {},
number = {},
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/ ; },
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 = {},
number = {},
pages = {177129},
doi = {10.1016/j.scitotenv.2024.177129},
pmid = {39461526},
issn = {1879-1026},
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 = {2024},
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},
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 st