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Bibliography on: Metagenomics

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ESP: PubMed Auto Bibliography 04 Nov 2024 at 01:31 Created: 

Metagenomics

While genomics is the study of DNA extracted from individuals — individual cells, tissues, or organisms — metagenomics is a more recent refinement that analyzes samples of pooled DNA taken from the environment, not from an individual. Like genomics, metagenomic methods have great potential in many areas of biology, but none so much as in providing access to the hitherto invisible world of unculturable microbes, often estimated to comprise 90% or more of bacterial species and, in some ecosystems, the bulk of the biomass. A recent describes how this new science of metagenomics is beginning to reveal the secrets of our microbial world: The opportunity that stands before microbiologists today is akin to a reinvention of the microscope in the expanse of research questions it opens to investigation. Metagenomics provides a new way of examining the microbial world that not only will transform modern microbiology but has the potential to revolutionize understanding of the entire living world. In metagenomics, the power of genomic analysis is applied to entire communities of microbes, bypassing the need to isolate and culture individual bacterial community members.

Created with PubMed® Query: ( metagenomic OR metagenomics OR metagenome ) NOT pmcbook NOT ispreviousversion

Citations The Papers (from PubMed®)

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RevDate: 2024-11-03

Zhang L, Xu W, Jiang J, et al (2024)

Metagenomic insights on promoting the removal of resistome in aerobic composting pig manure by lightly burned modified magnesite.

The Science of the total environment pii:S0048-9697(24)07258-9 [Epub ahead of print].

The antibiotic resistance genes (ARGs) have become a serious issue facing public health. In this study, light-burned magnesite with a high specific surface area at 650 °C (MS650) was used for aerobic composting, evaluating its effect on the resistome during pig manure composting. Different concentrations of MS650 reduced the abundance of the resistome, including seven high-risk ARGs, class two metal and biocide resistance genes (MBRGs), and human pathogenic bacteria (HPBs). The addition of 2.5 % MS650 (L1) in the composting had the best reduction effect on ARGs, MBRGs and HPBs. ARG and microbial community assembly are deterministic processes. Proteobacteria and Actinobacteria was the main factor associated with the decrease in ARGs, followed by virulence factor genes (VFGs, 44.2 %). The reduction in MBRGs by MS650 mainly suppressed HGT by reducing the Isfinder abundance. To summarize, MS650 is an effective method to improve emission reduction of ARGs and MBRGs. This study provided a theoretical basis for improving the engineering application potential of MS650.

RevDate: 2024-11-03

Liang W, Yan D, Zhang M, et al (2024)

Unraveling methanogenesis processes and pathways for Quaternary shallow biogenic gas in aquifer systems through geochemical, genomic and transcriptomic analyses.

The Science of the total environment pii:S0048-9697(24)07346-7 [Epub ahead of print].

Shallow biogenic gas is crucial in global warming and carbon cycling. Considering the knowledge gap in the understanding of methanogenesis and metabolic mechanisms within shallow groundwater systems, we investigated Quaternary shallow biogenic gas resources from the Hetao Basin in North China, which were previously underexplored. We systematically analyzed the genesis of gas and formation water, microbial communities, methanogenic processes, and pathways using geochemistry, genomics, and transcriptomics. Our findings indicated that active freshwater environments are conducive to microbial activity and the generation of primary microbial gases. A diverse range of microbes with functions, such as hydrolysis (e.g., Caulobacter), acidogenesis, and hydrogen production (e.g., Sediminibacterium), synergistically contributed to the methanogenic process. Methanogens predominantly comprised hydrogenotrophic methanogens (e.g., Methanobacteriales), although H2-dependent methylotrophic methanogens (e.g., Methanofastidiosa) were also prevalent. The metabolic processes of the different methanogenic pathways were revealed based on functional gene analysis and mapping results. Furthermore, the composition of the community structure, functional predictions, metagenomics, and metatranscriptomics underscored the contribution of the hydrogenotrophic pathway, which ranged from 52.22 % to 79.23 %. The aceticlastic pathway exhibited high gene abundance and was primarily associated with methylotrophs and other potential pathways. The H2-dependent methylotrophic methanogenesis pathway was constrained by low metabolic activity. By revealing the methane production mechanism of biogenic gas in shallow aquifer systems, this study provides a new perspective and profound comprehension of its ecological and environmental implications worldwide.

RevDate: 2024-11-03

Li T, Coker OO, Sun Y, et al (2024)

Multi-cohort analysis reveals altered archaea in colorectal cancer fecal samples across populations.

Gastroenterology pii:S0016-5085(24)05596-3 [Epub ahead of print].

BACKGROUND AND AIM: Archaea are important components of the host microbiome, but their roles in colorectal cancer (CRC) remain largely unclear. We aimed to elucidate the contribution of gut archaea to CRC across multiple populations.

METHODS: This study incorporated fecal metagenomic data from 10 independent cohorts from 7 countries and an additional in-house cohort, totaling 2101 metagenomes (748 CRC, 471 adenoma, and 882 healthy controls (HC)). Taxonomic profiling was performed using Kraken2 against the Genome Taxonomy Database. Alterations of archaeal communities and their interactions with bacteria and methanogenic functions were analyzed. Random Forest model was used to identify multicohort diagnostic microbial biomarkers in CRC.

RESULTS: The overall archaeal alpha diversity shifted from HC, adenoma patients to CRC patients with Methanobacteriota phylum enriched while order Methanomassiliicoccales depleted. At the species level, Methanobrevibacter_A smithii and Methanobrevibacter_A sp002496065 were enriched, while 8 species, including Methanosphaera stadtmanae and Methanomassiliicoccus_A intestinalis, were depleted in CRC patients across multiple cohorts. Among them, M. stadmanae, Methanobrevibacter_A sp900314695 and Methanocorpusculum sp001940805 exhibited a progressive decrease in the HC-adenoma-CRC sequence. CRC-depleted methanogenic archaea exhibited enhanced co-occurring interactions with butyrate-producing bacteria. Consistently, methanogenesis-related genes and pathways were enriched in CRC patients. A model incorporating archaeal and bacterial biomarkers outperformed single-kingdom models in discriminating CRC patients from healthy individuals with AUC ranging from 0.744 to 0.931 in leave-one-cohort-out analysis.

CONCLUSIONS: This multicohort analysis uncovered significant alterations in gut archaea and their interactions with bacteria in healthy individuals, adenoma patients and CRC patients. Archaeal biomarkers, combined with bacterial features, have potential as non-invasive diagnostic biomarkers for CRC.

RevDate: 2024-11-03

Witkabel P, C Abendroth (2024)

A systematic literature review of microbial ANAMMOX consortia in UASB/ EGSB-reactors.

Chemosphere pii:S0045-6535(24)02530-X [Epub ahead of print].

Anaerobic ammonium oxidation (ANAMMOX) poses an emerging research field as it can outstand previous processes of biological wastewater treatment in terms of efficiency and costs. Anammox bacteria have the ability to metabolise NH4[+] and NO2[-] to produce N2 under anaerobic conditions. Despite numerous studies, there is a lack of research on the co-occurrence and interrelationship of the predominant microbes that inhabit anammox-related processes. This systematic literature review follows the PSALSAR approach to assess metagenomic data on anammox bacteria and functional microbes in upstream reactors. Essential information on the physiology, metabolic pathways and inhibitory effects of anammox bacteria are reviewed and functional bacteria such as ammonia-oxidising bacteria (AOB), nitrite-oxidising bacteria (NOB), ammonia-oxidising Archaea (AOA) and denitrifying bacteria are identified. Candidatus Kuenenia and Candidatus Brocadia were the most frequently sequenced genera in the observed literature. Pseudomonadota, Chloroflexota and Bacteroidota were prevalent regardless of crucial operational parameters and configurations that affect the microbial community. Interrelationship analysis revealed a positive association between the versatility of a phylum's metabolism and its presence in the observed wastewater treatment literature. Several groups, such as Calditrichota, Myxococcota and Deinococcota are highly underrepresented, a finding that should be investigated in more detail. No evidence was found to suggest that high anammox ratios are correlated with high nitrogen removal efficiencies, as some studies found high efficiency despite low anammox abundance (<1%).

RevDate: 2024-11-03

Gregoris K, WH Pope (2024)

Extraction of high-quality metagenomic DNA from the lichens Flavoparmelia caperata and Peltigera membranacea.

Journal of microbiological methods pii:S0167-7012(24)00177-5 [Epub ahead of print].

Lichens are composite organisms found throughout temperate terrestrial forests, with species-specific associations with industrial air pollution. Metagenomic analysis of lichen samples requires robust nucleic acid extraction methodology, a process that is challenging due to the protective cortex layers, high polysaccharide content, and the vast diversity of the internal microbiome. Our method includes physical lysis through garnet bead beating, chemical lysis using a sodium dodecyl sulfate buffer, phenol:chloroform:isoamyl alcohol extraction, and ethanol precipitation. The method was tested on three different lichen samples from two distinct species and yielded metagenomic DNA suitable for sequencing and PCR amplification. This procedure addresses the issues associated with DNA extraction from lichen using common laboratory equipment and reagents without the utilization of liquid nitrogen. This paper presents a cost-effective and accessible DNA extraction method for obtaining high-quality genetic material from dried and preserved lichen specimens.

RevDate: 2024-11-03

Ji J, Zhao Y, Wu G, et al (2024)

Responses of endogenous partial denitrification process to acetate and propionate as carbon sources: Nitrite accumulation performance, microbial community dynamic changes, and metagenomic insights.

Water research, 268(Pt A):122680 pii:S0043-1354(24)01579-3 [Epub ahead of print].

Endogenous partial denitrification (EPD) offered a promising pathway for supplying nitrite to anammox, and it also enabled energy-efficient and cost-effective nitrogen removal. However, information about the impact of different carbon sources on the EPD system was limited, and the metabolic mechanisms remained unclear. This study operated the EPD system for 180 days with various acetate and propionate ratios over eight phases. The nitrate-to-nitrite transformation ratio (NTR) decreased from 81.7 % to 0.4 % as the acetate/propionate (Ac/Pr) ratio shifted from 3:0 to 0:3, but the NTR returned to 86.1 % after propionate was replaced with acetate. Typical cycles indicated that PHB (126.8 and 133.9 mg COD/g VSS, respectively) was mainly stored, facilitating a higher NTR (87.8 % and 67.7 %, respectively) on days 58 and 180 in the presence of acetate. In contrast, on day 158 in the presence of propionate, PHV (84.8 mg COD/g VSS) was predominantly stored, resulting in negligible nitrite accumulation (0.2 mg N/L). Metagenomic analysis revealed that the microbial community structure did not significantly change, and the (narGHI+napAB)/nirKS ratio consistently exceeded 7:2, despite variations in the carbon source. Compared with acetate, propionate as carbon source reduced the abundance of genes encoding NADH-producing enzymes (e.g., mdh), likely owing to a shift in PHAs synthesis and degradation pathways. Consequently, limited NADH affected electron distribution and transfer rates, thereby decreasing the nitrate reduction rate and causing nitrite produced by narGHI and napAB to be immediately reduced by nirKS. This study provided new insights and guidance for EPD systems to manage the conditions of carbon deficiency or complex carbon sources.

RevDate: 2024-11-03

Guo XP, Chen XJ, Sidikjan N, et al (2024)

Silver nanoparticles regulate antibiotic resistance genes by shifting bacterial community and generating anti-silver genes in estuarine biofilms.

Aquatic toxicology (Amsterdam, Netherlands), 276:107131 pii:S0166-445X(24)00301-1 [Epub ahead of print].

Biofilms are thought to be sinks for antibiotic resistance genes (ARGs) and nanoparticles (NPs), however, studies on the interactions between NPs and ARGs in biofilms are limited. This study focused on the occurrence and regulatory mechanisms of ARGs during the formation of biofilms with continuous treatment of zero-valent silver nanoparticles (Ag[0]-NPs) and Ag ions at an environmental concentration of 10 µg/L in the Yangtze Estuary. The biofilms could enrich large amounts of Ag, with the highest concentration of 97.60 mg/kg and 111.08 mg/kg in the Ag[0]-NPs and Ag ions group at 28 days. Compared to the blank at 28 days, the abundance of ARGs was reduced 2.2 times in the Ag[0]-NPs group, whereas it increased 1.3 times in the Ag ion group. Ag[0]-NPs and Ag ions induced the production of silver resistance genes (SRGs) or selected bacteria with SRGs in biofilms. Based on machine learning, the bacterial community, SRGs, and Ag concentration were the top three dominant regulators of ARGs, with 27.74 %, 25.57 %, and 17.93 % contributions, respectively. Structural equation modeling revealed that Ag could indirectly regulate ARGs by regulating the bacterial community in the Ag[0]-NPs group. Metagenomic sequencing further showed that most of the decreased ARGs were hosted by Betaproteobacteria in the Ag[0]-NPs groups. According to the KEGG pathway database, the possible molecular mechanism of Ag[0]-NPs/Ag ions regulating ARGs may be through the two-component system (arlS/silS-arlR) and beta-lactam resistance system (mexI-mexV-oprM/oprZ/smeF). Overall, this study provides new insights into the effects of Ag[0]-NPs at environmental concentrations on the ecological environment, especially regarding the mechanism of regulating ARGs in estuarine biofilms.

RevDate: 2024-11-03
CmpDate: 2024-11-03

Jiang L, Han L, Zhong Y, et al (2024)

High utility of bronchoalveolar lavage fluid metagenomic next-generation sequencing approach for etiological diagnosis of pneumonia.

BMC infectious diseases, 24(1):1232.

BACKGROUND: For patients with pneumonia, the rapid detection of pathogens is still a major global problem in clinical practice because traditional diagnostic techniques for infection are time-consuming and insensitive. Metagenomic next-generation sequencing (mNGS) is a novel technique that has the potential to improve pathogen diagnosis. This study aimed to investigate the microbiological diagnostic ability of mNGS compared with conventional culture and to determine the optimal time to test patients for pneumonia.

METHODS: A prospective study using data from June 2020 to June 2021 was performed at a tertiary teaching hospital in China. We included 56 patients from all adult patients with a clinical diagnosis of pneumonia. Blood and bronchoalveolar lavage fluid (BALF) samples were taken for simultaneous mNGS and conventional culture testing.

RESULTS: All 56 patients underwent both conventional culture and mNGS. Of these patients, 37 were diagnosed with severe pneumonia and 17 were diagnosed with non-severe pneumonia. The top three pathogenic bacteria detected by mNGS were Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Enterococcus faecium was detected more frequently in the non-severe pneumonia group (4 vs. 0, p < 0.05). The findings revealed that the detection rate of mNGS (84%) was superior to that of conventional culture methods (48%). Notably, the percentage of mNGS-positive BALF samples (46/56, 82.14%) was significantly greater than that of blood samples (27/56, 48.21%). The etiological comparison demonstrated that mNGS-positive samples, which received clinical approval, tended to be associated with a more normalized temperature, lower PCO2 levels, and a higher SOFA score than mNGS-negative samples (p = 0.022, p = 0.0.028, and p = 0.038, respectively).

CONCLUSIONS: In this study, we discovered that the etiology of lung infections frequently involves multiple pathogens. The use of mNGS in BALF is instrumental for detecting nonviral pathogens associated with lung infections. Although the rate of positive blood NGS results is significantly influenced by various clinical factors, for patients suspected of having viral, Legionella, or tsutsugamushi infections, plasma mNGS could serve as a complementary diagnostic tool.

RevDate: 2024-11-03
CmpDate: 2024-11-03

Yao QH, Zhi HL, Xia XJ, et al (2024)

Primary cutaneous infections with non-tuberculous mycobacteria: a report of 6 cases.

BMC infectious diseases, 24(1):1231.

BACKGROUND: The incidence of non-tuberculous mycobacterium infection has shown a gradual increasing trend in recent years, among which cutaneous manifestations as an important aspect. This study aimed to describe the clinical features and microbiological findings in 6 cases of primary cutaneous nontuberculous mycobacterium infection.

METHODS: In this retrospective study from June 2021 to June 2022, the clinical data and microbiological results of six cases diagnosed with primary cutaneous non-tuberculous mycobacterium infection in department of dermatology, Hangzhou Third People's Hospital were analyzed.

RESULTS: All six cases were primary cutaneous non-tuberculous mycobacterium infections, four of which had a history of trauma or exposure, and two had an underlying disease that could lead to compromised immunity. All patients presented with erythema nodular skin lesions, four on the upper or lower extremities, one on the face, and one on the right hip. The histopathological findings of five patients who underwent biopsy were granulomatous inflammatory changes with mixed infiltration. Laboratory cultures using tissue or tissue fluid were all successful, including four Mycobacterium marinum, one Mycobacterium abscessus, and one Mycobacterium avium. Metagenomics next-generation sequencing detected results consistent with culture colonies in only two cases. With the exception of case 4, all patients responded well to oral medication, with a course of treatment ranging from 4 months to 1 year, and the prognosis was good.

CONCLUSIONS: The clinical features of primary cutaneous non-tuberculous mycobacterium infection are often lacking in specificity, and the identification of related strains is difficult for a variety of reasons. Although the results of metagenomics next-generation sequencing are useful for pathogen spectrum identification, its diagnostic value should be carefully reevaluated under certain circumstances. Patients with suspected triggers who do not respond well to conventional treatments should be suspected as atypical infection and potential immunosuppression. If diagnosed and treated promptly, the prognosis of primary cutaneous non-tuberculous mycobacterium infection is generally good.

RevDate: 2024-11-03
CmpDate: 2024-11-03

Qi M, Du Y, Guan J, et al (2024)

The clinical management and efficacy of metagenomic next-generation sequencing in patients with pyogenic spinal infection: a single-center cohort study.

Journal of orthopaedic surgery and research, 19(1):716.

OBJECTIVE: This study aims to evaluate the clinical management and effectiveness of metagenomic next-generation sequencing (mNGS) in patients with pyogenic spinal infections.

METHODS: We conducted a retrospective review of 17 patients diagnosed with pyogenic spinal infections and treated at our institution between October 2022 and February 2024. The cohort included 8 males and 9 females, with a mean age of 63.59 ± 10.18 years (range: 41-71 years). The infections comprised 9 epidural abscesses, 6 intervertebral space infections, and 2 deep abscesses. All patients underwent open surgical procedures and mNGS-based bacterial identification using intraoperative pus or tissue specimens, in addition to conventional blood bacterial cultures. Clinical outcomes were assessed using CRP, PCT, WBC inflammatory markers, and VAS scores postoperatively.

RESULTS: All 17 patients with pyogenic spinal infections underwent open surgery and mNGS bacterial detection at our institution. Among the 17 patients, mNGS yielded positive results in 14 cases (82.4%), significantly higher than the 5.9% positivity rate of conventional bacterial cultures (p < 0.001). The mNGS test time was notably shorter than conventional cultures (1.0 vs. 5.88 days, p < 0.001). Postoperative antibiotic therapy was adjusted based on mNGS findings. There were significant reductions in postoperative VAS, WBC, PCT, and CRP values compared to preoperative levels (p < 0.01).

CONCLUSION: Metagenomic next-generation sequencing is effective in managing pyogenic spinal infections by facilitating rapid and sensitive detection of pathogens. This technique improves the timeliness and accuracy of diagnosis, highlighting its potential for broader clinical use.

RevDate: 2024-11-03
CmpDate: 2024-11-03

Geat N, Singh D, Saha P, et al (2024)

Deciphering Phyllomicrobiome of Cauliflower Leaf: Revelation by Metagenomic and Microbiological Analysis of Tolerant and Susceptible Genotypes Against Black Rot Disease.

Current microbiology, 81(12):439.

Understanding the phyllomicrobiome dynamics in cauliflower plants holds significant promise for enhancing crop resilience against black rot disease, caused by Xanthomonas campestris pv. campestris. In this study, the culturable microbiome and metagenomic profile of tolerant (BR-161) and susceptible (Pusa Sharad) cauliflower genotypes were investigated to elucidate microbial interactions associated with disease tolerance. Isolation of phyllospheric bacteria from asymptomatic and black rot disease symptomatic leaves of tolerant and susceptible cultivars yielded 46 diverse bacterial isolates. Molecular identification via 16S rRNA sequencing revealed differences in the diversity of microbial taxa between genotypes and health conditions. Metagenomic profiling using next-generation sequencing elucidated distinct microbial communities, with higher diversity observed in black rot disease symptomatic leaf of BR-161. Alpha and beta diversity indices highlighted differences in microbial community structure and composition between genotypes and health conditions. Taxonomic analysis revealed a core microbiome consisting of genera such as Xanthomonas, Psychrobacillus, Lactobacillus, and Pseudomonas across all the samples. Validation through microbiological methods confirmed the presence of these key genera. The findings provide novel insights into the phyllomicrobiome of black rot-tolerant and susceptible genotypes of cauliflower. Harnessing beneficial microbial communities identified in this study offers promising avenues for developing sustainable strategies to manage black rot disease and enhance cauliflower crop health and productivity.

RevDate: 2024-11-03
CmpDate: 2024-11-03

Li X, Cheng R, Zhang C, et al (2024)

Genomic diversity of phages infecting the globally widespread genus Sulfurimonas.

Communications biology, 7(1):1428.

The widespread bacterial genus Sulfurimonas is metabolically versatile and occupies a key ecological niche in different habitats, but its interaction with bacteriophages remains unexplored. Here we systematically investigated the genetic diversity, taxonomy and interaction patterns of Sulfurimonas-associated phages based on sequenced microbial genomes and metagenomes. High-confidence phage contigs related to Sulfurimonas were retrieved from various ecosystems, clustered into 61 viral operational taxonomic units across three viral realms, including Duplodnaviria, Monodnaviria and Varidnaviria. Head-tail phages of Caudoviricetes were assigned to 19 genus-level viral clusters, the majority of which were distantly related to known viruses. Notably, diverse double jelly-roll viruses and inoviruses were also linked to Sulfurimonas, representing two commonly overlooked phage groups. Historical and current phage infections were revealed, implying viral impact on the evolution of host adaptive immunity. Additionally, phages carrying auxiliary metabolic genes might benefit hosts by compensating or augmenting sulfur metabolism. This study highlights the diversity and novelty of Sulfurimonas-associated phages with divergent tailless lineages, providing basis for further investigation of phage-host interactions within this genus.

RevDate: 2024-11-02
CmpDate: 2024-11-02

De Luca D, Piredda R, Scamardella S, et al (2024)

Taxonomic and metabolic characterisation of biofilms colonising Roman stuccoes at Baia's thermal baths and restoration strategies.

Scientific reports, 14(1):26290.

Stuccoes are very delicate decorative elements of Roman age. Very few of them survived almost intact to present days and, for this reason, they are of great interest to restorers and conservators. In this study, we combined metabarcoding and untargeted metabolomics to characterise the taxonomic and metabolic profiles of the microorganisms forming biofilms on the stuccoes located on the ceiling of the laconicum, a small thermal environment in the archaeological park of Baia (southern Italy). We found that some samples were dominated by bacteria while others by eukaryotes. Additionally, we observed high heterogeneity in the type and abundance of bacterial taxa, while the eukaryotic communities, except in one sample (at prevalence of fungi), were dominated by green algae. The metabolic profiles were comparable across samples, with lipids, lipid-like molecules and carbohydrates accounting for roughly the 50% of metabolites. In vitro and in vivo tests to remove biofilms on stuccoes using essential oils blends were successful at a 50% dilution for one hour and half. This integrative study advanced our knowledge on taxonomic and metabolic profiles of biofilms on ancient stuccoes and highlighted the potential impacts of these techniques in the field of cultural heritage conservation.

RevDate: 2024-11-02

Xiao C, Ide K, Matsunaga H, et al (2024)

Metagenomic profiling of antibiotic resistance genes and their associations with the bacterial community along the Kanda River, an urban river in Japan.

Journal of bioscience and bioengineering pii:S1389-1723(24)00281-0 [Epub ahead of print].

Antibiotic resistance genes (ARGs) present in urban rivers have the potential to disseminate antibiotic-resistant bacteria into other environments, posing significant threats to both ecological and public health. Although metagenomic analyses have been widely employed to detect ARGs in rivers, our understanding of their dynamics across different seasons in diverse watersheds remains limited. In this study, we performed a comprehensive genomic analysis of the Kanda River in Japan at 11 sites from upstream to estuary throughout the year to assess the spread of ARGs and their associations with bacterial communities. Analysis of 110 water samples using the 16S rRNA gene revealed variations in bacterial composition corresponding to seasonal changes in environmental parameters along the river. Shotgun metagenomics-based profiling of ARGs in 44 water samples indicated higher ARG abundance downstream, particularly during the summer. Weighted gene co-expression network analysis (WGCNA) linking bacterial lineages and ARGs revealed that 12 ARG subtypes co-occurred with 128 amplicon sequence variants (ASVs). WGCNA suggested potential hosts for ErmB, ErmF, ErmG, tetQ, tet (W/N/W), aadA2, and adeF, including gut-associated bacteria (e.g., Prevotella, Bacteroides, Arcobacter) and indigenous aquatic microbes (e.g., Limnohabitans and C39). In addition, Pseudarcobacter (a later synonym of Arcobater) was identified as a host for adeF, which was also confirmed by single cell genomics. This study shows that ARG distribution in urban rivers is affected by seasonal and geographical factors and demonstrates the importance of monitoring rivers using multiple types of genome sequencing, including 16S rRNA gene sequencing, metagenomics, and single cell genomics.

RevDate: 2024-11-02

Zhao Y, Zhang J, Zheng Y, et al (2024)

Overlooked dissemination risks of antimicrobial resistance through green tide proliferation.

Water research, 268(Pt B):122714 pii:S0043-1354(24)01613-0 [Epub ahead of print].

Green tides, particularly those induced by Enteromorpha, pose significant environmental challenges, exacerbated by climate change, coastal eutrophication, and other anthropogenic impacts. More concerningly, these blooms may influence the spread of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) within ecosystems. However, the manner in which Enteromorpha blooms affect the distribution and spread of antimicrobial resistance (AMR) remains uncertain. This study investigated ARG profiles, dynamic composition, and associated health risks within the Enteromorpha phycosphere and surrounding seawater in typical bays (Jiaozhou, Aoshan, and Lingshan) in the South Yellow Sea. The Enteromorpha phycosphere exhibited significantly higher ARG abundance (p < 0.05) but lower diversity compared to the surrounding seawater. Source-tracking and metagenomic analyses revealed that the phycosphere was the main contributor to the resistome of surrounding seawater. Moreover, resistant pathogens, especially ESKAPE pathogens, with horizontal gene transfer (HGT) potential, were more abundant in the phycosphere than in the surrounding seawater. The phycosphere released high-risk ARGs to the surrounding seawater during Enteromorpha blooms, posing serious health and ecological AMR risks in marine environments. This study highlights the significant role of Enteromorpha blooms in ARG spread and associated risks, urging a reassessment of AMR burden from a public health perspective.

RevDate: 2024-11-02

Berckx F, Van Nguyen T, Hilker R, et al (2024)

Host dependent specialized metabolism of nitrogen export in actinorhizal nodules induced by Frankia cluster-2.

Journal of experimental botany pii:7866822 [Epub ahead of print].

Frankia cluster-2 strains are diazotrophs that engage in root nodule symbiosis with actinorhizal plants of the Cucurbitales and the Rosales. Previous studies have shown that an assimilated nitrogen source, presumably arginine, is exported to the host in nodules of Datisca glomerata (Cucurbitales), while a different metabolite is exported in the nodules of Ceanothus thyrsiflorus (Rosales). To investigate if an assimilated nitrogen form is commonly exported to the host by cluster-2 strains, and which metabolite would be exported in Ceanothus, we analysed gene expression levels, metabolite profiles, and enzyme activities in nodules. We conclude that the export of assimilated nitrogen in symbiosis seems to be a common feature for Frankia cluster-2 strains, but which source is host-dependent. The export of assimilated ammonium to the host suggests that 2-oxoglutarate is drawn from the TCA cycle at a high rate. This specialised metabolism obviates the need for the reductive branch of the TCA cycle. We found several genes encoding enzymes of the central carbon and nitrogen metabolism were lacking in Frankia cluster-2 genomes: the glyoxylate shunt and succinate semialdehyde dehydrogenase. This led to a linearization of the TCA cycle, and we hypothesize this could explain the low saprotrophic potential of Frankia cluster-2.

RevDate: 2024-11-02
CmpDate: 2024-11-02

Kosch TA, Torres-Sánchez M, Liedtke HC, et al (2024)

The Amphibian Genomics Consortium: advancing genomic and genetic resources for amphibian research and conservation.

BMC genomics, 25(1):1025.

Amphibians represent a diverse group of tetrapods, marked by deep divergence times between their three systematic orders and families. Studying amphibian biology through the genomics lens increases our understanding of the features of this animal class and that of other terrestrial vertebrates. The need for amphibian genomic resources is more urgent than ever due to the increasing threats to this group. Amphibians are one of the most imperiled taxonomic groups, with approximately 41% of species threatened with extinction due to habitat loss, changes in land use patterns, disease, climate change, and their synergistic effects. Amphibian genomic resources have provided a better understanding of ontogenetic diversity, tissue regeneration, diverse life history and reproductive modes, anti-predator strategies, and resilience and adaptive responses. They also serve as essential models for studying broad genomic traits, such as evolutionary genome expansions and contractions, as they exhibit the widest range of genome sizes among all animal taxa and possess multiple mechanisms of genetic sex determination. Despite these features, genome sequencing of amphibians has significantly lagged behind that of other vertebrates, primarily due to the challenges of assembling their large, repeat-rich genomes and the relative lack of societal support. The emergence of long-read sequencing technologies, combined with advanced molecular and computational techniques that improve scaffolding and reduce computational workloads, is now making it possible to address some of these challenges. To promote and accelerate the production and use of amphibian genomics research through international coordination and collaboration, we launched the Amphibian Genomics Consortium (AGC, https://mvs.unimelb.edu.au/amphibian-genomics-consortium) in early 2023. This burgeoning community already has more than 282 members from 41 countries. The AGC aims to leverage the diverse capabilities of its members to advance genomic resources for amphibians and bridge the implementation gap between biologists, bioinformaticians, and conservation practitioners. Here we evaluate the state of the field of amphibian genomics, highlight previous studies, present challenges to overcome, and call on the research and conservation communities to unite as part of the AGC to enable amphibian genomics research to "leap" to the next level.

RevDate: 2024-11-02
CmpDate: 2024-11-02

Wardi M, Lemkhente Z, Alla AA, et al (2024)

Resistome analysis of wastewater treatment plants in Agadir city, Morocco, using a metagenomics approach.

Scientific reports, 14(1):26328.

Water scarcity has evolved into a pressing global issue, significantly impacting numerous regions worldwide. The use of treated wastewater stands out as a promising solution to this problem. However, the proliferation of various contaminants, primarily Antimicrobial Resistance Genes (ARGs), poses a significant challenge to its safe and sustainable use. In this study, we assessed the composition and abundance of 373 ARGs, corresponding to 31 different classes of antibiotics, in six wastewater treatment plants (WWTP) in Agadir city of Morocco. Influent and effluent samples were collected during the months of February and July in 2020, in addition to samples from the Atlantic Ocean. In total, 223 ARGs were uncovered, highlighting in particular resistance to aminoglycoside, macrolide lincosamide, beta-lactamase, chloramphenicol, sulfonamide, tetracycline, and other antibiotics. The mechanisms of action of these ARGs were mainly antibiotic inactivation, antibiotic target alteration, efflux pump and cellular protection. Mobile genetic elements (MGEs) were detected at high levels their co-occurrence with ARGs highlights their involvement in the acquisition and transmission of ARGs in microbial communities through horizontal gene transfer. While many wastewater treatment methods effectively reduce a large proportion of gene material and pathogens, a substantial fraction of ARGs and other contaminants persist in treated wastewater. This persistence poses potential risks to both human health and the environment, warranting the need of more effective treatment strategies.

RevDate: 2024-11-02
CmpDate: 2024-11-02

Sato T, Abe K, Koseki J, et al (2024)

Survivability and life support in sealed mini-ecosystems with simulated planetary soils.

Scientific reports, 14(1):26322.

Establishing a sustainable life-support system for space exploration is a formidable challenge due to the vast distances, high costs, and environmental differences from Earth. Building upon the lessons from the Biosphere 2 experiment, we introduce the novel "Ecosphere" and "Biosealed" systems, self-sustaining ecosystems within customizable, enclosed containers. These systems incorporate terrestrial ecosystems and groundwater layers, offering a potential model for transplanting Earth-like biomes to extraterrestrial environments. Over 4 years, we conducted rigorous experiments and analyses to understand the dynamics of these enclosed ecosystems. We successfully mitigated moisture deficiency, a major obstacle to plant growth, by incorporating groundwater layers. Additionally, we quantified microbial communities proliferating in specific soils, including simulated lunar and Ryugu asteroid regolith, enhance plant cultivation in space environments. Metagenomic analysis of these simulated space soils revealed diverse microbial populations and their crucial role in plant growth and ecosystem stability. Notably, we identified symbiotic relationships between plants and Cyanobacteria, enhancing oxygen production, and demonstrated the potential of LED lighting as an alternative light source for plant cultivation in sun-limited space missions. We also confirmed the survival of fruit flies within these systems, relying on plant-produced oxygen and photosynthetic bacteria. Our research provides a comprehensive framework for developing future space life-support systems. The novelty of our work lies in the unique design of our enclosed ecosystems, incorporating groundwater layers and simulated extraterrestrial soils, and the detailed analysis of microbial communities within these systems. These findings offer valuable insights into the challenges and potential solutions for establishing sustainable human habitats in space, including the importance of microbial management and potential health concerns related to microbial exposure.

RevDate: 2024-11-01

Williams AD, Leung VW, Tang JW, et al (2024)

Ancient environmental microbiomes and the cryosphere.

Trends in microbiology pii:S0966-842X(24)00253-1 [Epub ahead of print].

In this review, we delineate the unique set of characteristics associated with cryosphere environments (namely, ice and permafrost) which present both challenges and opportunities for studying ancient environmental microbiomes (AEMs). In a field currently reliant on several assumptions, we discuss the theoretical and empirical feasibility of recovering microbial nucleic acids (NAs) from ice and permafrost with varying degrees of antiquity. We also summarize contamination control best practices and highlight considerations for the latest approaches, including shotgun metagenomics, and downstream bioinformatic authentication approaches. We review the adoption of existing software and provide an overview of more recently published programs, with reference to their suitability for AEM studies. Finally, we summarize outstanding challenges and likely future directions for AEM research.

RevDate: 2024-11-02

Tang X, Yao Q, Jiang X, et al (2024)

Response of ammonium transformation in bioanodes to potential regulation: Performance, electromicrobiome and implications.

Bioresource technology, 415:131731 pii:S0960-8524(24)01435-4 [Epub ahead of print].

Understanding how potential regulation affects ammonium transformation in bioanodes is crucial for promoting their application. This study explored the performance, electrochemical properties, electromicrobiome of bioanodes across potentials from 0.0 V to 0.4 V vs. standard hydrogen electrode (SHE). Higher anode potentials enhanced the performance of electroactive biofilms and ammonium removal but suppressed nitrite oxidation while favoring dissimilatory nitrate reduction (DNRA), leading to increased nitrite accumulation. A reduction in nitrite-oxidizing bacteria (NOB) and an increase in DNRA-related genes resulted in an optimal nitrite-to-ammonium ratio of 1.32 for the Anammox process. Higher anodic potentials (0.3 and 0.4 V) were less effective for TN removal than lower potentials (0, 0.1, and 0.2 V), likely due to increased NOB and denitrification genes at lower potentials enhancing nitrite oxidation and denitrification. These findings indicate that regulating anodic potential effectively directs ammonium transformation in bioanodes, optimizing its conversion to N2 or nitrite.

RevDate: 2024-11-01

Zhang H, Cheng S, Yan W, et al (2024)

Interplay between vanadium distribution and microbial community in soil-plant system.

Journal of hazardous materials, 480:136303 pii:S0304-3894(24)02882-6 [Epub ahead of print].

Soil-plant system play an essential role in distribution and transformation of vanadium (V). V shapes the diversity of soil communities, while soil microorganisms mediate V transformation. Plants also absorb V from surrounding soil. However, the study of microbial response to V stress in different soil-plant compartments is limited, and the metabolic functions driving V transformation across these systems remain elusive. The study investigates the distribution of V in soil-plant systems nearby a V smelter. 16S rRNA sequencing and metagenomics are utilized to reveal the microbial adaptation and V transformation in bulk soil, rhizosphere, and endosphere. Bothriochloa ischaemum (L.) Keng. (BK) exhibits higher phytoextraction potential (TF = 0.74 ± 0.26). Environmental variables, including pH, V, OM, and AP, show significant (p < 0.05) influence in soil community composition, with homogeneous selection governing the assembly processes in bulk soil and rhizosphere, while stochastic process dominates endospheric assembly. Metagenomic investigation revealed a coordinated metabolic pathway between functional taxa in soil and plants, which lead to root uptake and translocation. V stress is mitigated through Nocardioide, Microvirga, and Solirubrobacter, putatively harboring V(V) reduction genes n arG and mtrC in soil. In rhizosphere, citrate synthase gltA and alkaline phosphatase phoD exhibit functional potential to facilitate formation of V-complexation to increase V mobility. In endoshere, endophytic Enterobacter further detoxifies V(V), and likely promotes V translocation through siderophore biosynthesis gene, iucA. These findings enhance our understanding on interplay between V and microbial community in soil-plant systems, which is instrumental in developing mitigation plan for V contaminated sites.

RevDate: 2024-11-01
CmpDate: 2024-11-01

Achudhan AB, LM Saleena (2024)

Comparative genomic analysis and characterization of novel high-quality draft genomes from the coal metagenome.

World journal of microbiology & biotechnology, 40(12):370.

Coal, a sedimentary rock harbours a complex microbial community that plays a significant role in its formation and characteristics. However, coal metagenome sequencing and studies were less, limiting our understanding of this complex ecosystem. This study aimed to reconstruct high-quality metagenome-assembled genomes (MAGs) from the coal sample collected in the Neyveli mine to explore the unrevealed diversity of the coal microbiome. Using Illumina sequencing, we obtained high-quality raw reads in FASTQ format. Subsequently, de novo assembly and binning with metaWRAP software facilitated the reconstruction of coal MAGs. Quality assessment using CheckM identified 10 High-Quality MAGs (HQ MAGs), 7 medium-quality MAGs (MQ MAGs), and 6 low-quality MAGs (LQ MAGs). Further analysis using GTDB-Tk revealed four HQ MAGs as known species like Dermacoccus abyssi, Sphingomonas aquatilis, Acinetobacter baumannii, and Burkholderia cenocepacia. The remaining six HQ MAGs were classified as Comamonas, Arthrobacter, Noviherbaspirillum, Acidovorax, Oxalicibacterium, and Bordetella and designated as novel genomes by the validation of digital DNA-DNA hybridization (dDDH). Phylogenetic analysis and further pangenome analysis across the phylogenetic groups revealed a similar pattern with a high proportion of cloud genes. We further analysed the functional potential of these MAGs and closely related genomes using COG. The comparative functional genomics revealed that novel genomes are highly versatile, potentially reflecting adaptations to the coal environment. BlastKOALA was used to conduct a detailed analysis of the metabolic pathways associated with the MAGs. This study highlights the comparative genomic analysis of novel coal genomes with their closely related genomes to understand the evolutionary relationships and functional properties.

RevDate: 2024-11-01
CmpDate: 2024-11-01

Hasegawa-Takano M, Hosaka T, Kojima K, et al (2024)

Cyanorhodopsin-II represents a yellow-absorbing proton-pumping rhodopsin clade within cyanobacteria.

The ISME journal, 18(1):.

Microbial rhodopsins are prevalent in many cyanobacterial groups as a light-energy-harvesting system in addition to the photosynthetic system. It has been suggested that this dual system allows efficient capture of sunlight energy using complementary ranges of absorption wavelengths. However, the diversity of cyanobacterial rhodopsins, particularly in accumulated metagenomic data, remains underexplored. Here, we used a metagenomic mining approach, which led to the identification of a novel rhodopsin clade unique to cyanobacteria, cyanorhodopsin-II (CyR-II). CyR-IIs function as light-driven outward H+ pumps. CyR-IIs, together with previously identified cyanorhodopsins (CyRs) and cyanobacterial halorhodopsins (CyHRs), constitute cyanobacterial ion-pumping rhodopsins (CyipRs), a phylogenetically distinct family of rhodopsins. The CyR-II clade is further divided into two subclades, YCyR-II and GCyR-II, based on their specific absorption wavelength. YCyR-II absorbed yellow light (λmax = 570 nm), whereas GCyR-II absorbed green light (λmax = 550 nm). X-ray crystallography and mutational analysis revealed that the difference in absorption wavelengths is attributable to slight changes in the side chain structure near the retinal chromophore. The evolutionary trajectory of cyanobacterial rhodopsins suggests that the function and light-absorbing range of these rhodopsins have been adapted to a wide range of habitats with variable light and environmental conditions. Collectively, these findings shed light on the importance of rhodopsins in the evolution and environmental adaptation of cyanobacteria.

RevDate: 2024-11-01

Feng L, Guo Z, Yao W, et al (2024)

Metagenomics and Untargeted Metabolomics Analysis Revealed the Probiotic and Postbiotic Derived from Lactiplantibacillus plantarum DPUL F232 Alleviate Whey Protein-Induced Food Allergy by Reshaping Gut Microbiota and Regulating Key Metabolites.

Journal of agricultural and food chemistry [Epub ahead of print].

Postbiotics have emerged as a promising alternative to probiotics. However, it remains unclear whether postbiotics can exert regulatory effects on intestinal flora and metabolism as probiotics. Thus, we investigated the effects of probiotic and postbiotic in rats with whey protein-induced food allergy, which demonstrated that postbiotic intervention effectively alleviated allergy symptoms, reduced serum immunoglobulin E (IgE) and mast cell protease-1 (mMCP-1) levels, and regulated the type helper 1 cell/2 cell (Th1/Th2) balance in both serum and spleen. Metagenomic analysis revealed that postbiotics induced more significant changes in intestinal flora. Untargeted metabolomics analysis showed that both probiotics and postbiotics significantly up-regulated various differential metabolites, which were negatively correlated with immune indices, including malvidin-3-glucoside, 3,4-dihydroxymandelic acid, nicotinamide, triterpenoids, pirbuterol, and 4-hydroxybenzoic acid. This study confirms that postbiotics can alleviate food allergies and regulate intestinal flora and metabolites, which provides a valuable reference for the use of postbiotics in mitigating allergic diseases through gut microbiota and metabolite modulation.

RevDate: 2024-11-01
CmpDate: 2024-11-01

Gao L, Rao MPN, Liu YH, et al (2024)

SALINITY-Induced Changes in Diversity, Stability, and Functional Profiles of Microbial Communities in Different Saline Lakes in Arid Areas.

Microbial ecology, 87(1):135.

Saline lakes, characterized by high salinity and limited nutrient availability, provide an ideal environment for studying extreme halophiles and their biogeochemical processes. The present study examined prokaryotic microbial communities and their ecological functions in lentic sediments (with the salinity gradient and time series) using 16S rRNA amplicon sequencing and a metagenomic approach. Our findings revealed a negative correlation between microbial diversity and salinity. The notable predominance of Archaea in high-salinity lakes signified a considerable alteration in the composition of the microbial community. The results indicate that elevated salinity promotes homogeneous selection pressures, causing substantial alterations in microbial diversity and community structure, and simultaneously hindering interactions among microorganisms. This results in a notable decrease in the complexity of microbial ecological networks, ultimately influencing the overall ecological functional responses of microbial communities such as carbon fixation, sulfur, and nitrogen metabolism. Overall, our findings reveal salinity drives a notable predominance of Archaea, selects for species adapted to extreme conditions, and decreases microbial community complexity within saline lake ecosystems.

RevDate: 2024-11-01

Virachabadoss VRA, Appavoo MS, Paramasivam KS, et al (2024)

The addition of humic acid into soil contaminated with microplastics enhanced the growth of black gram (Vigna mungo L. Hepper) and modified the rhizosphere microbial community.

Environmental science and pollution research international [Epub ahead of print].

Microplastics have polluted agricultural soils, posing a substantial risk to crop productivity. Moreover, the presence of microplastic pollution has caused a disturbance in the composition of the microbial community in the soil surrounding plant roots, therefore impacting the growth of beneficial bacteria. A study was conducted to examine if humic acid (HA) can counteract the harmful effects of microplastics (MPs) on the growth of black gram crops and the composition of the rhizosphere soil microbial community, to reduce the negative impacts of microplastics on these microorganisms and crops. The research was carried out using mud pots and the plastic utilized for the experiment consisted of 60% high-density polyethylene (HDPE) and 40% polypropylene (PP). The soil was enriched with lignite-based potassium humate, which had a pH range of 8.0-9.5 and with 65% humic acid. The experiment consisted of six treatments: T1, which served as the control without HA and MP; T2, which involved the use of HA at a concentration of 0.15% w/w; T3, which involved the use of MP at a concentration of 0.2% w/w; T4, which involved the use of MP at a concentration of 0.4% w/w; T5, which involved the combination of HA at a concentration of 0.15% w/w and MP at a concentration of 0.2% w/w; and T6, which involved the combination of HA at a concentration of 0.15% w/w and MP at a concentration of 0.4% w/w. The plant growth characteristics, including germination percentage, nodule number, and chlorophyll content, were measured. In addition, the DNA obtained from the rhizosphere soil was analyzed using metagenomics techniques to investigate the organization of the microbial population. Seedlings in soil polluted with MP exhibited delayed germination compared to seedlings in uncontaminated soil. Following 60 days of growth, the soil samples treated with T5 (0.2% MP and 0.15% HA w/w) had the highest population of bacteria and rhizobium, with counts 5.58 ± 0.02 and 4.90 ± 0.02 CFU g[-1] soil. The plants cultivated in T5 had the most elevated chlorophyll-a concentration (1.340 ± 0.06 mg g[-1]), and chlorophyll-b concentration (0.62 ± 0.02 mg g[-1]) while those cultivated in T3 displayed the lowest concentration of chlorophyll-a (0.59 ± 0.02 mg g[-1]) and chlorophyll-b (0.21 ± 0.04 mg g[-1]). Within the phylum, Proteobacteria had the highest prevalence in all treatments. However, when the soil was polluted with MPs, its relative abundance was reduced by 8.4% compared to the control treatment (T1). Conversely, treatment T5 had a 3.76% rise in relative abundance when compared to treatment T3. The predominant taxa found in soil polluted with MP were Sphingomonas and Bacillus, accounting for 19.3% of the total. Sphingomonas was the predominant genus (21.2%) in soil polluted with MP and supplemented with humic acid. Humic acid can be used as a soil amendment to mitigate the negative effects of MPs and enhance their positive advantages. Research has demonstrated that incorporating humic acid into soil is a viable method for maintaining the long-term integrity of soil's physical, chemical, and biological characteristics.

RevDate: 2024-11-01
CmpDate: 2024-11-01

Fernandez-Garcia MD, Garcia-Ibañez N, Camacho J, et al (2024)

Enhanced echovirus 11 genomic surveillance in neonatal infections in Spain following a European alert reveals new recombinant forms linked to severe cases, 2019 to 2023.

Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin, 29(44):.

BackgroundIn 2023, a European alert was issued regarding an increase in severe enterovirus (EV) neonatal infections associated with echovirus 11 (E11) new lineage 1.AimTo analyse E11-positive cases between 2019 and 2023 to investigate whether the new lineage 1 circulated in Spain causing severe neonatal infections.MethodsEV-positive samples from hospitalised cases are sent for typing to the National Reference Enterovirus Laboratory. Available samples from 2022-23 were subjected to metagenomic next-generation sequencing.ResultsOf 1,288 samples genotyped, 103 were E11-positive (98 patients: 6 adults, 33 neonates, 89 children under 6 years; male to female ratio 1.9). E11 detection rate was similar before and after detection of the new lineage 1 in Spain in June 2022 (9.7% in 2019 vs 10.6% in 2023). The proportion of E11-infected ICU-admitted neonates in 2019-2022 (2/7) vs 2022-2023 (5/12) did not significantly differ (p = 0.65). In severe neonatal infections, 4/7 E11 strains were not linked to the new lineage 1. The three novel E11 recombinant genomes were associated with severe (n = 2) and non-severe (n = 1) cases from 2022-2023 and clustered outside the new lineage 1. Coinfecting pathogenic viruses were present in four of 10 E11-positive samples.ConclusionThe emergence of the new lineage 1 is not linked with an increase in incidence or severity of neonatal E11 infections in Spain. The detection of two novel E11 recombinants associated with severe disease warrants enhancing genomic and clinical surveillance.

RevDate: 2024-11-01
CmpDate: 2024-11-01

Yang Q, Chen X, Kou G, et al (2024)

A rare case of prostatic malakoplakia with multidrug-resistant Escherichia coli: a case report.

BMC infectious diseases, 24(1):1226.

Prostatic malakoplakia is an uncommon chronic inflammatory disorder, tumor-like but non-cancerous, the diagnosis of which pivots crucially on the identification of characteristic Michaelis-Gutmann bodies within the pathological tissue. We hereby present an inaugural case report of prostatic malakoplakia concurrent with sepsis caused by multidrug-resistant Escherichia coli, verified through blood culture and metagenomic next-generation sequencing (mNGS). The pathogenesis might be associated with infections by Escherichia coli, immune system irregularities, or lysosomal dysfunction. Although the patient had no chronic underlying diseases, he presented early with sepsis and multi-organ dysfunction. This case emphasizes the imperative to further investigate the association between malakoplakia and Escherichia coli, the necessity for prompt diagnosis, and the supportive role of mNGS, and the treatment strategy focuses on rapid control of infection and systemic inflammatory response.

RevDate: 2024-11-01

Neugent ML, Hulyalkar NV, Ghosh D, et al (2024)

Urinary biochemical ecology reveals microbiome-metabolite interactions and metabolic markers of recurrent urinary tract infection.

bioRxiv : the preprint server for biology pii:2024.10.22.619727.

Recurrent urinary tract infections (rUTIs) are a major clinical challenge in postmenopausal women and their increasing prevalence underscores the need to define interactions between the host and the urinary microbiome that may underlie rUTI susceptibility. A body of work has identified the taxonomic profile of the female urinary microbiome associate with aging, menopause, and urinay disease. However, how this microbial community engages with the host niche, including the local biochemical environment of the urogenital tract, in health and disease is yet to be fully defined. This study directly assesses differences in the biochemical environment of the urine, or biochemical ecology, associated with recurrent urinary tract infection (UTI) and defines a microbe-metabolite association network of the female urinary microbiome. By integrating metagenomic and metabolomic data collected from a controlled cohort of women with rUTI, we find that distinct metabolites, such as methionine sulfoxide (Met-SO) and trimethylamine oxide (TMAO), are associated with differences in urinary microbiome diversity. We observe associations between microbial and biochemical beta diversity and unique metabolic networks of uropathogenic Escherichia coli and uroprotective Lactobacillus species, highlighting potential metabolite-driven ecological shifts that may influence UTI susceptibility. We identify a urinary lipid signature of active rUTI that can accurately distinguish (AUC = 0.987) cases controls. Finally, using time-to-relapse data we identify deoxycholic acid (DCA) as a new prognostic indicator for rUTI recurrence. Together these findings suggest that systemic metabolic processes may influence susceptibility, opening new avenues for therapeutic intervention and the development of more accurate diagnostic and prognostic to improve patient outcomes.

RevDate: 2024-11-01

Pita S, Myers PN, Johansen J, et al (2024)

CHAMP delivers accurate taxonomic profiles of the prokaryotes, eukaryotes, and bacteriophages in the human microbiome.

Frontiers in microbiology, 15:1425489.

INTRODUCTION: Accurate taxonomic profiling of the human microbiome composition is crucial for linking microbial species to health outcomes. Therefore, we created the Clinical Microbiomics Human Microbiome Profiler (CHAMP), a comprehensive tool designed for the profiling of prokaryotes, eukaryotes, and viruses across all body sites.

METHODS: CHAMP uses a reference database derived from 30,382 human microbiome samples, covering 6,567 prokaryotic and 244 eukaryotic species, as well as 64,003 viruses. We benchmarked CHAMP against established profiling tools (MetaPhlAn 4, Bracken 2, mOTUs 3, and Phanta) using a diverse set of in silico metagenomes and DNA mock communities.

RESULTS: CHAMP demonstrated unparalleled species recall, F1 score, and significantly reduced false positives compared to all other tools benchmarked. The false positive relative abundance (FPRA) for CHAMP was, on average, 50-fold lower than the second-best performing profiler. CHAMP also proved to be more robust than other tools at low sequencing depths, highlighting its application for low biomass samples.

DISCUSSION: Taken together, this establishes CHAMP as a best-in-class human microbiome profiler of prokaryotes, eukaryotes, and viruses in diverse and complex communities across low and high biomass samples. CHAMP profiling is offered as a service by Clinical Microbiomics A/S and is available for a fee at https://cosmosidhub.com.

RevDate: 2024-11-01
CmpDate: 2024-11-01

Chen G, Ren Q, Zhong Z, et al (2024)

Exploring the gut microbiome's role in colorectal cancer: diagnostic and prognostic implications.

Frontiers in immunology, 15:1431747.

The intricate interplay between the gut microbiome and colorectal cancer (CRC) presents novel avenues for early diagnosis and prognosis, crucial for improving patient outcomes. This comprehensive review synthesizes current findings on the gut microbiome's contribution to CRC pathogenesis, highlighting its potential as a biomarker for non-invasive CRC screening strategies. We explore the mechanisms through which the microbiome influences CRC, including its roles in inflammation, metabolism, and immune response modulation. Furthermore, we assess the viability of microbial signatures as predictive tools for CRC prognosis, offering insights into personalized treatment approaches. Our analysis underscores the necessity for advanced metagenomic studies to elucidate the complex microbiome-CRC nexus, aiming to refine diagnostic accuracy and prognostic assessment in clinical settings. This review propels forward the understanding of the microbiome's diagnostic and prognostic capabilities, paving the way for microbiome-based interventions in CRC management.

RevDate: 2024-11-01

Hillege LE, Trepka KR, Ziemons J, et al (2024)

Metagenomic analysis during capecitabine therapy reveals microbial chemoprotective mechanisms and predicts drug toxicity in colorectal cancer patients.

medRxiv : the preprint server for health sciences pii:2024.10.11.24315249.

PURPOSE: Unpredictable chemotherapy side effects are a major barrier to successful treatment. Cell culture and mouse experiments indicate that the gut microbiota is influenced by and influences anti-cancer drugs. However, metagenomic data from patients paired to careful side effect monitoring remains limited. Herein, we focus on the oral fluoropyrimidine capecitabine (CAP). We investigate CAP-microbiome interactions through metagenomic sequencing of longitudinal stool sampling from a cohort of advanced colorectal cancer (CRC) patients.

METHODS: We established a prospective cohort study including 56 patients with advanced CRC treated with CAP monotherapy across 4 centers in the Netherlands. Stool samples and clinical questionnaires were collected at baseline, during cycle 3, and post-treatment. Metagenomic sequencing to assess microbial community structure and gene abundance was paired with transposon mutagenesis, targeted gene deletion, and media supplementation experiments. An independent US cohort was used for model validation.

RESULTS: CAP treatment significantly altered gut microbial composition and pathway abundance, enriching for menaquinol (vitamin K2) biosynthesis genes. Transposon library screens, targeted gene deletions, and media supplementation confirmed that menaquinol biosynthesis protects Escherichia coli from drug toxicity. Microbial menaquinol biosynthesis genes were associated with decreased peripheral sensory neuropathy. Machine learning models trained in this cohort predicted hand-foot syndrome and dose reductions in an independent cohort.

CONCLUSION: These results suggest treatment-associated increases in microbial vitamin biosynthesis serve a chemoprotective role for bacterial and host cells, with implications for toxicities outside the gastrointestinal tract. We provide a proof-of-concept for the use of microbiome profiling and machine learning to predict drug toxicities across independent cohorts. These observations provide a foundation for future human intervention studies, more in-depth mechanistic dissection in preclinical models, and extension to other cancer treatments.

RevDate: 2024-10-31
CmpDate: 2024-10-31

Hoffmann A, Hoffmann J, Ruegamer T, et al (2024)

New diagnostic techniques for diagnosing facture-related infections.

Injury, 55 Suppl 6:111898.

The diagnosis of fracture-related infections (FRI) is challenging and requires interdisciplinary efforts. Many diagnostic approaches are based on the algorithms established for prosthetic joint infections (PJI). Data specific to FRI are limited. Microbiological diagnostics include tissue culture, sonication, and molecular methods. Novel metagenomic analyses are increasingly being used in clinical diagnostic practice. In addition to bacterial detection, the study of host tissue factors has the potential to transform the diagnostics of FRI by facilitating the assesment of clinical significance in clinical samples. The integration of host tissue analysis into microbiology reports has great potential to improve the diagnosis of FRI. This mini-review describes the potential improvement of diagnostic techniques by integrating new approaches into the diagnostic algorithm of fracture-related infections.

RevDate: 2024-10-31
CmpDate: 2024-10-31

Ding C, Chen R, Guo P, et al (2024)

A case of Fitz-Hugh-Curtis syndrome diagnosed by noninvasive metagenomic next-generation sequencing.

Taiwanese journal of obstetrics & gynecology, 63(6):935-940.

OBJECTIVE: Fitz-Hugh-Curtis Syndrome (FHCS) is an inflammation of the liver capsule as a complication of pelvic inflammatory disease (PID) in sexually active women, mostly associated with Chlamydia trachomatis (C. trachomatis) and Neisseria gonorrhoeae. Classically presenting as sharp right upper quadrant pain, usually accompanied salpingitis and ascites. With nonspecific clinical presentation and poor specificity, definitive diagnosis needs tissue biopsy and culture by laparoscopy.

CASE REPORT: We report the case of a 22-year-old female with a 2-month history of abdominal pain and distention. Symptomatic relief when supportive treatments were given, with the ultrasound and PET-CT suggested advanced bilateral ovarian cancer. After metagenomic next-generation sequencing (mNGS) detected C. trachomatis in ascitic fluid. Following anti-infective medication, clinical improvement was satisfactory and the patient was discharged.

CONCLUSION: FHCS with distention was rare and challenging to diagnose. The mNGS would be a potent, non-invasive pathogen detection method with significant sensitivity and specificity.

RevDate: 2024-10-31
CmpDate: 2024-10-31

Zhu S, Mao H, Sun S, et al (2025)

Arbuscular mycorrhizal fungi promote functional gene regulation of phosphorus cycling in rhizosphere microorganisms of Iris tectorum under Cr stress.

Journal of environmental sciences (China), 151:187-199.

The mutualistic symbiotic system formed by clumping arbuscular mycorrhizal fungi (AMF) and plants can remediate heavy metal-contaminated soils. However, the specific mechanisms underlying the interaction between AMF and inter-root microbial communities, particularly their impact on organic phosphorus (P) cycling, remain unclear. This study investigated the gene regulation processes involved in inter-root soil phosphorus cycling in wetland plants, specifically Iris tectorum, following inoculation with AMF under varying concentrations of chromium (Cr) stress. Through macro-genome sequencing, we analyzed the composition and structure of the inter-root soil microbial community associated with Iris tectorum under greenhouse pot conditions. The results demonstrated significant changes in the diversity and composition of the inter-root soil microbial community following AMF inoculation, with Proteobacteria, Actinobacteria, Chloroflexi, Acidobacteria, and Bacteroidetes being the dominant taxa. Under Cr stress, species and gene co-occurrence network analysis revealed that AMF promoted the transformation process of organic phosphorus mineralization and facilitated inorganic phosphorus uptake. Additionally, network analysis of functional genes indicated strong aggregation of (pstS, pstA, pstC, TC.PIT, phoR, pp-gppA) genes, which collectively enhanced phosphorus uptake by plants. These findings shed light on the inter-root soil phosphorus cycling process during the co-remediation of Cr-contaminated soil by AMF-Iris tectorum symbiosis, providing valuable theoretical support for the application of AMF-wetland plant symbiosis systems to remediate heavy metal-contaminated soil.

RevDate: 2024-10-31

Li X, Li Y, Wang Y, et al (2024)

Methodology comparison of environmental sediment fungal community analysis.

Environmental research pii:S0013-9351(24)02167-4 [Epub ahead of print].

Fungi play important roles in ecosystems. Analyzing fungal communities in environments has long been a challenge due to the large difference in compositions retrieved using different methods or sequencing regions, obscuring the true abundance and species information. Our study aimed to compare and determine more accurate approach for evaluating fungal populations in river sediment. To achieve this, different primer sets in the internal transcribed spacer (ITS) (ITS5/ITS1R, ITS1F/ITS2), 18S rRNA gene (0817F/1196R) for High-throughput sequencing (HTS), metagenomic shotgun sequencing (MS) directly from environmental samples, and HTS using ITS primers for the fungal samples collected from plate cultivation were used to characterize the fungal communities. We calculated diversity index and used FungalTraits to analyze methods preferences for fungal species. The study revealed that when analyzing the fungal species directly from environmental samples, amplification and sequencing of ITS region demonstrated more accuracy than MS and 18S rRNA gene sequencing methods, but displayed significant primer preference. Over 30 % fungal species from HTS after plate cultivation were not present in HTS from the environmental samples. NMDS analysis demonstrated significant disparities in species diversity among different methods, suggesting potential complementarity between them. Over 85% species identified by HTS using ITS primers belonged to filamentous fungi, while the MS mostly identified yeast (62%). Therefore, to get more accurate fungal community information in sediment, multiple methods were recommended by using cultivation, molecular biological methods dependent on PCR techniques like ITS1F/ITS2 primer for HTS and PCR independent method such as metagenomic shotgun sequencing techniques.

RevDate: 2024-10-31

Deehan EC, Al Antwan S, Witwer RS, et al (2024)

Perspective: Revisiting the Concepts of Prebiotic and Prebiotic Effect in Light of Scientific and Regulatory Progress - A Consensus Paper from the Global Prebiotic Association (GPA).

Advances in nutrition (Bethesda, Md.) pii:S2161-8313(24)00163-7 [Epub ahead of print].

The term prebiotic has been used for almost three decades and has undergone numerous updates over the years. The scientific literature reveals that despite continuous efforts to establish a globally unified definition to guide jurisdictional regulations and product innovations, ambiguity continues to surround the terms prebiotic and prebiotic effect, leading to products that lack in full regulatory adherence being marketed worldwide. Thus, to reflect the current state of scientific research and knowledge and for the continuous advancement of the category, an update to the current prebiotic definition is warranted. This update includes removing the term selectivity, considering additional locations of action besides the gut, highlighting prebiotic performance benefits such as cognitive and athletic, and providing a clear standalone definition for prebiotic effect. The Global Prebiotic Association (GPA) is a leading information and industry hub committed to raising awareness about prebiotics, their emerging and well-established health benefits, and prebiotic product integrity and efficacy. In this position paper, GPA builds on previous prebiotic definitions to propose the following expanded definition for prebiotic: "a compound or ingredient that is utilized by the microbiota producing a health or performance benefit." In addition to prebiotic, GPA also defines prebiotic effect as: "a health or performance benefit that arises from alteration of the composition and/or activity of the microbiota, as a direct or indirect result of the utilization of a specific and well-defined compound or ingredient by microorganisms." With these two definitions, GPA aims to paint a clearer picture for the term prebiotic, and by incorporating an industry point of view, these updated definitions may be used alongside current scientific and regulatory perspectives to move the category forward. STATEMENT OF SIGNIFICANCE: The purpose of this paper is to revisit the concepts of prebiotic and prebiotic effect by providing a scientific-based industry perspective. The proposed definitions of prebiotic and prebiotic effect reflect the recent discoveries in metagenomics and prebiotic research after the International Scientific Association for Probiotics and Prebiotics' (ISAPP's) 2017 prebiotic definition and propose terminology changes that are timely and necessary. These changes aim to maintain the clarity and usefulness of the prebiotic definition to the scientific community, industry, healthcare providers, and consumers, while ensuring scientific validity, comprehensiveness, and justification of each part of the prebiotic definition, including abandoning the term selectivity and introducing concepts of performance benefits and prebiotic effect.

RevDate: 2024-10-31

Yao M, Ren A, Yang X, et al (2024)

Unveiling the influence of heating temperature on biofilm formation in shower hoses through multi-omics.

Water research, 268(Pt B):122704 pii:S0043-1354(24)01603-8 [Epub ahead of print].

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.

RevDate: 2024-10-31

Huang DQ, Yang JH, Han NN, et al (2024)

Microbial coadaptation drives the dynamic stability of microecology in mainstream and sidestream anammox systems under exposure of progesterone.

Water research, 268(Pt B):122694 pii:S0043-1354(24)01593-8 [Epub ahead of print].

Microbial cooperation determines the efficacy of wastewater biological treatment, and the adaptability of microorganisms to environmental stresses varies. Recently, extensive use of hormones results in their inevitable discharge into aquatic environment. Therefore, mainstream and sidestream anammox reactors were constructed in this study to evaluate their removal performance of progesterone and nitrogen simultaneously, the adaptability of anammox consortia to progesterone stress and the corresponding regulation mechanism. Both anammox processes had the resilience to progesterone stress, with the average nitrogen removal efficiency exceeding 90 %. At the same time, progesterone removal efficiency also exceeded 70 %. In contrast, microbial community in the mainstream reactors was more susceptible to progesterone interference. The adaptation of anammox consortia mainly depended on microbial cooperation and molecular regulation. Initially, bacteria secreted more extracellular polymeric substances to detain progesterone. Biodegradation also contributed to mitigating the side effect of progesterone, which was demonstrated by the proliferation of potential degrading bacteria such as Bacillus salacetis, Bacillus wiedmannii and Rhodococcus erythropolis. In addition, the enhancement of microbial interaction intensity drove their cooperation to enhance adaptability and maintain stable performance. Combined with metagenomic and metatranscriptomic analyses, such microbial adaptability was enhanced through molecular regulations, including the energy redistribution for amino acid synthesis and alteration of key metabolic pathways. Related functional gene expressions and microbial interactions were, in turn, regulated by quorum sensing. This work verifies the feasibility of anammox process in hormone-containing wastewater treatment and provides a holistic understanding of molecular mechanism of microbial interaction and coadaptation to stress.

RevDate: 2024-10-31
CmpDate: 2024-10-31

Dobrzyński J, A Naziębło (2024)

Paenibacillus as a Biocontrol Agent for Fungal Phytopathogens: Is P. polymyxa the Only One Worth Attention?.

Microbial ecology, 87(1):134.

Control of fungal phytopathogens is a significant challenge in modern agriculture. The widespread use of chemical fungicides to control these pathogens often leads to environmental and food contamination. An eco-friendly alternative that can help reduce reliance on these chemicals is plant growth-promoting bacteria (PGPB), particularly those of the genus Paenibacillus, which appear to be highly effective. The review aims to summarize the existing knowledge on the potential of Paenibacillus spp. as fungal biocontrol agents, identify knowledge gaps, and answer whether other species of the genus Paenibacillus, in addition to Paenibacillus polymyxa, can also be effective biocontrol agents. Paenibacillus spp. can combat plant phytopathogens through various mechanisms, including the production of lipopeptides (such as fusaricidin, paenimyxin, and pelgipeptin), the induction of systemic resistance (ISR), hydrolytic enzymes (chitinase, cellulase, and glucanase), and volatile organic compounds. These properties enable Paenibacillus strains to suppress the growth of fungi such as Fusarium oxysporum, F. solani, Rhizoctonia solani, Botrytis cinerea, or Colletotrichum gloeosporioides. Notably, several strains of Paenibacillus, including P. polymyxa, P. illinoisensis KJA-424, P. lentimorbus B-30488, and P. elgii JCK1400, have demonstrated efficacy in controlling fungal diseases in plants. Importantly, many formulations with Paenibacillus strains have already been patented, and some are commercially available, but most of them contain only P. polymyxa. Nevertheless, considering the data presented in this review, we believe that other strains from the Paenibacillus genus (besides P. polymyxa) will also be commercialized and used in plant protection in the future. Importantly, there is still limited information regarding their impact on the native microbiota, particularly from the metataxonomic and metagenomic perspectives. Expanding knowledge in this area could enhance the effectiveness of biocontrol agents containing Paenibacillus spp., ensuring safe and sustainable use of biological fungicides.

RevDate: 2024-10-31

Agosti P, Kouraki A, Dionisi T, et al (2024)

Gut Microbiome Diversity and Composition Correlates With Time in the Therapeutic Range in Patients on Warfarin Treatment: A Pilot Study.

RevDate: 2024-10-31

Chen Y, Chen C, Chen W, et al (2024)

Clinical Application of Metagenomic Next-Generation Sequencing in Sepsis Patients with Early Antibiotic Treatment.

Infection and drug resistance, 17:4695-4706.

PURPOSE: This study aimed to evaluate the clinical utility of metagenomic next-generation sequencing (mNGS) in sepsis patients who received early empirical antibiotic treatment.

PATIENTS AND METHODS: A retrospective analysis was conducted on clinical data from sepsis patients diagnosed in the Emergency Intensive Care Unit (EICU) between April 2019 and May 2023. All patients underwent standard conventional microbiological testing. Patients were categorized into either the mNGS group or the control group based on whether they underwent mNGS tests. Baseline variables were matched using propensity scores.

RESULTS: Out of 461 sepsis patients screened, 130 were included after propensity matching, with 65 patients in each group. Despite prior antibiotic treatment, 57 cases (87.69%) in the mNGS group had positive mNGS results, exceeding the culture detection rate (52.31%). Besides, a higher proportion of patients in the mNGS group experienced antibiotic adjustments compared to the control group (72.31% vs 53.85%). Mortality rates were also compared based on the duration of antibiotic exposure before mNGS sampling. Patients exposed to antibiotics for less than 24 hours had a lower mortality rate compared to those exposed for over 8 days (22.22% vs 42.86%). COX multivariate analysis identified mNGS testing, underlying diseases, lymphocyte percentage, infection site (respiratory and bloodstream) as independent risk factors for mortality in sepsis patients.

CONCLUSION: With increased antibiotic exposure time, the positive rate of culture testing significantly decreased (44.44% vs 59.52% vs 35.71%, P = 0.031), whereas the positive rate of mNGS remained stable (77.78% vs 88.10% vs 92.86%, P = 0.557). mNGS demonstrated less susceptibility to antibiotic exposure. Early mNGS detection positively impacted the prognosis of sepsis patients.

RevDate: 2024-10-31

Wang X, Gu D, Zhang L, et al (2024)

mNGS-identified cellulitis due to quinolone-resistant Edwardsiella tarda: a case report.

Frontiers in medicine, 11:1413561.

Edwardsiella tarda is frequently isolated from aquatic animals and environments. While human infections caused by E. tarda are rare, some extraintestinal infections can be severe. This case report describes a patient with cellulitis of the right upper extremity of unknown origin. Metagenomic next-generation sequencing (mNGS) indicated that the patient was infected with E. tarda. Antimicrobial susceptibility testing revealed that the isolate was resistant to quinolones and trimethoprim/sulfamethoxazole. The isolate, positive for four virulence genes (fimA, gadB, mukF, and sodB), was confirmed to be virulent using the Galleria mellonella larvae model. Following early pus drainage and a 9-day course of imipenem, the patient ultimately recovered. This case report aimed to illustrate the presentation, diagnosis, and management of uncommon cellulitis caused by drug-resistant, virulent E. tarda.

RevDate: 2024-10-31
CmpDate: 2024-10-31

Favero F, Re A, Dason MS, et al (2024)

Characterization of gut microbiota dynamics in an Alzheimer's disease mouse model through clade-specific marker-based analysis of shotgun metagenomic data.

Biology direct, 19(1):100.

Alzheimer's disease (AD) is a complex neurodegenerative disorder significantly impairing cognitive faculties, memory, and physical abilities. To characterize the modulation of the gut microbiota in an in vivo AD model, we performed shotgun metagenomics sequencing on 3xTgAD mice at key time points (i.e., 2, 6, and 12 months) of AD progression. Fecal samples from both 3xTgAD and wild-type mice were collected, DNA extracted, and sequenced. Quantitative taxon abundance assessment using MetaPhlAn 4 ensured precise microbial community representation. The analysis focused on species-level genome bins (SGBs) including both known and unknown SGBs (kSGBs and uSGBs, respectively) and also comprised higher taxonomic categories such as family-level genome bins (FGBs), class-level genome bins (CGBs), and order-level genome bins (OGBs). Our bioinformatic results pinpointed the presence of extensive gut microbial diversity in AD mice and showed that the largest proportion of AD- and aging-associated microbiome changes in 3xTgAD mice concern SGBs that belong to the Bacteroidota and Firmicutes phyla, along with a large set of uncharacterized SGBs. Our findings emphasize the need for further advanced bioinformatic studies for accurate classification and functional analysis of these elusive microbial species in relation to their potential bridging role in the gut-brain axis and AD pathogenesis.

RevDate: 2024-10-31

Chen YJ, Altshuler I, Freyria NJ, et al (2024)

Arctic's hidden hydrocarbon degradation microbes: investigating the effects of hydrocarbon contamination, biostimulation, and a surface washing agent on microbial communities and hydrocarbon biodegradation pathways in high-Arctic beaches.

Environmental microbiome, 19(1):81.

BACKGROUND: Canadian Arctic summer sea ice has dramatically declined due to global warming, resulting in the rapid opening of the Northwest Passage (NWP), slated to be a major shipping route connecting the Atlantic and Pacific Oceans by 2040. This development elevates the risk of oil spills in Arctic regions, prompting growing concerns over the remediation and minimizing the impact on affected shorelines.

RESULTS: This research aims to assess the viability of nutrient and a surface washing agent addition as potential bioremediation methods for Arctic beaches. To achieve this goal, we conducted two semi-automated mesocosm experiments simulating hydrocarbon contamination in high-Arctic beach tidal sediments: a 32-day experiment at 8 °C and a 92-day experiment at 4 °C. We analyzed the effects of hydrocarbon contamination, biostimulation, and a surface washing agent on the microbial community and its functional capacity using 16S rRNA gene sequencing and metagenomics. Hydrocarbon removal rates were determined through total petroleum hydrocarbon analysis. Biostimulation is commonly considered the most effective strategy for enhancing the bioremediation process in response to oil contamination. However, our findings suggest that nutrient addition has limited effectiveness in facilitating the biodegradation process in Arctic beaches, despite its initial promotion of aliphatic hydrocarbons within a constrained timeframe. Alternatively, our study highlights the promise of a surface washing agent as a potential bioremediation approach. By implementing advanced -omics approaches, we unveiled highly proficient, unconventional hydrocarbon-degrading microorganisms such as Halioglobus and Acidimicrobiales genera.

CONCLUSIONS: Given the receding Arctic sea ice and the rising traffic in the NWP, heightened awareness and preparedness for potential oil spills are imperative. While continuously exploring optimal remediation strategies through the integration of microbial and chemical studies, a paramount consideration involves limiting traffic in the NWP and Arctic regions to prevent beach oil contamination, as cleanup in these remote areas proves exceedingly challenging and costly.

RevDate: 2024-10-31
CmpDate: 2024-10-31

Lai X, Liu S, Miao J, et al (2024)

Eubacterium siraeum suppresses fat deposition via decreasing the tyrosine-mediated PI3K/AKT signaling pathway in high-fat diet-induced obesity.

Microbiome, 12(1):223.

BACKGROUND: Obesity in humans can lead to chronic diseases such as diabetes and cardiovascular disease. Similarly, subcutaneous fat (SCF) in pigs affects feed utilization, and excessive SCF can reduce the feed efficiency of pigs. Therefore, identifying factors that suppress fat deposition is particularly important. Numerous studies have implicated the gut microbiome in pigs' fat deposition, but research into its suppression remains scarce. The Lulai black pig (LL) is a hybrid breed derived from the Laiwu pig (LW) and the Yorkshire pig, with lower levels of SCF compared to the LW. In this study, we focused on these breeds to identify microbiota that regulate fat deposition. The key questions were: Which microbial populations reduce fat in LL pigs compared to LW pigs, and what is the underlying regulatory mechanism?

RESULTS: In this study, we identified four different microbial strains, Eubacterium siraeum, Treponema bryantii, Clostridium sp. CAG:413, and Jeotgalibaca dankookensis, prevalent in both LW and LL pigs. Blood metabolome analysis revealed 49 differential metabolites, including tanshinone IIA and royal jelly acid, known for their anti-adipogenic properties. E. siraeum was strongly correlated with these metabolites, and its genes and metabolites were enriched in pathways linked to fatty acid degradation, glycerophospholipid, and glycerolipid metabolism. In vivo mouse experiments confirmed that E. siraeum metabolites curb weight gain, reduce SCF adipocyte size, increase the number of brown adipocytes, and regulate leptin, IL-6, and insulin secretion. Finally, we found that one important pathway through which E. siraeum inhibits fat deposition is by suppressing the phosphorylation of key proteins in the PI3K/AKT signaling pathway through the reduction of tyrosine.

CONCLUSIONS: We compared LW and LL pigs using fecal metagenomics, metabolomics, and blood metabolomics, identifying E. siraeum as a strain linked to fat deposition. Oral administration experiments in mice demonstrated that E. siraeum effectively inhibits fat accumulation, primarily through the suppression of the PI3K/AKT signaling pathway, a critical regulator of lipid metabolism. These findings provide a valuable theoretical basis for improving pork quality and offer insights relevant to the study of human obesity and related chronic metabolic diseases. Video Abstract.

RevDate: 2024-10-31
CmpDate: 2024-10-31

Mehlferber EC, Arnault G, Joshi B, et al (2024)

A cross-systems primer for synthetic microbial communities.

Nature microbiology, 9(11):2765-2773.

The design and use of synthetic communities, or SynComs, is one of the most promising strategies for disentangling the complex interactions within microbial communities, and between these communities and their hosts. Compared to natural communities, these simplified consortia provide the opportunity to study ecological interactions at tractable scales, as well as facilitating reproducibility and fostering interdisciplinary science. However, the effective implementation of the SynCom approach requires several important considerations regarding the development and application of these model systems. There are also emerging ethical considerations when both designing and deploying SynComs in clinical, agricultural or environmental settings. Here we outline current best practices in developing, implementing and evaluating SynComs across different systems, including a focus on important ethical considerations for SynCom research.

RevDate: 2024-10-31

Žilka M, Hrabovský M, Dušička J, et al (2024)

Comparative analysis of airborne fungal spore distribution in urban and rural environments of Slovakia.

Environmental science and pollution research international [Epub ahead of print].

Monitoring airborne fungal spores is crucial for public health and plant production since they belong to important aeroallergens and phytopathogens. Due to different land use, their concentration can differ significantly between urban and rural areas. We monitored their spectrum and quantity on two geographically close sites with a different degree of urbanisation: Bratislava City and Kaplna Village in Slovakia, located 38 km apart. We recorded the spectrum of airborne fungal spores over a year and confirmed the microscopic results by amplicon-based metagenomic analysis. The main spore season of the most frequent genera lasted over a week longer in Kaplna, but its intensity was approximately two-fold higher in Bratislava. This can be possibly connected to the microclimatic conditions of the urban area (especially wind speed and heat island effect) and the lesser use of fungicides. Cladosporium was the dominant genus on both sites, influencing the intensity most significantly. Through statistical analysis of the influence of meteorological parameters on airborne fungal spore levels, we identified a significant relationship with temperature, while the impact of other parameters varied depending on the spore type and release mechanism. Our results show the differences in airborne fungal spore levels between urban and rural areas and highlight the necessity for more monitoring stations in various environments.

RevDate: 2024-10-30
CmpDate: 2024-10-30

Hua Q, Chi X, Wang Y, et al (2024)

Biological damage of monocrotaline on the brain and intestinal tissues of Apis mellifera.

Pesticide biochemistry and physiology, 205:106158.

Monocrotaline (MCT) is a toxic alkaloid present in plants, posing a threat to animals in terrestrial ecosystems. However, little is known about its potential impacts on pollinating insects. Here, we report the effects of of MCT on the brains and intestines of foraging honeybees (Apis mellifera). MCT exposure resulted in a reduction in head weight and swelling of the abdomen in honeybees. Additionally, MCT exposure caused morphological damage to the brain, characterized by decreased antioxidant capacity and increased apoptosis, along with intestinal tissue damage that was accompanied by increased antioxidant capacity and apoptosis. Moreover, MCT altered the core gut microbial community structure in honeybees and increased the expression of antimicrobial peptide (AMP) genes in the midgut. These findings indicate that exposure to MCT activates the immune response in the honeybee gut, while the brain does not exhibit an immune response but instead experiences oxidative stress. This study provides a resource for future research exploring interactions between MCT and other insects, and can help deepen our understanding of MCT's potential impacts in ecosystems.

RevDate: 2024-10-30

Liu L, Han X, Hu J, et al (2024)

Jointly considering multi-medium and full-cycle to better reveal distribution and removal of antibiotic resistance genes in long-term constructed wetland.

The Science of the total environment pii:S0048-9697(24)07433-3 [Epub ahead of print].

Constructed wetlands (CWs) have been proven to effectively remove antibiotic resistance genes (ARGs) at different experimental scales; however, there is still a lack of researches on the removal and monitoring of ARGs during the actual operation of full-scale CWs. To fill this gap, this study selected the Annan constructed wetland in Beijing as a case study and utilized quantitative sequencing, metagenomic analysis, and other technical methods to determine characteristics of ARGs in CWs during different operating periods. Furthermore, we analysed the overall removal characteristics of ARGs in the CW during different operating periods and differences of ARG distribution in three media. The dominant ARGs in the CW were quinolone, β-lactam and tetracycline, with subtypes of tufA and fusA. ARG distributions are significantly influenced by anthropic activities and seasonal changes. Three periods of the CW had good removal effects on special ARGs, but there were differences in the removal characteristics of different types and subtypes of ARGs. The CW had removal effects on four types of ARGs (such as multidrugs), 16 types of fusidic acid, and nine types of ARGs (such as bleomycin) during the dormancy, start-up, and operation periods, respectively. Among ARG subtypes, the CW had removal effects on 37, 53, and 51 subtypes during the dormancy, start-up, and operation periods, respectively. The subtypes that were removed mainly included those containing tetracycline, efflux pump, and β-lactam, mcr-1, and mcr-5 (colistin ARGs). For individual parts of CWs, the removal effects on the total abundance of ARGs were as follows: forebay > surface flow wetland > subsurface flow wetland. These findings provide insights for optimizing the purification efficiency of CWs for ARGs.

RevDate: 2024-10-30

Vinayagam S, Seker K, Rajendran D, et al (2024)

The genetic composition of Anopheles mosquitoes and the diverse population of gut-microbiota within the Anopheles subpictus and Anopheles vagus mosquitoes in Tamil Nadu, India.

Acta tropica pii:S0001-706X(24)00320-6 [Epub ahead of print].

In recent days, in tropical and subtropical regions, secondary vectors of Anopheles mosquitoes are becoming more important in transmitting diseases to humans as primary vectors. Various molecular techniques have separated closely related Anopheles subpictus and Anopheles vagus mosquitoes based on their diversity with other mosquito species. Despite their widespread distribution, the An. subpictus and An. vagus mosquitoes, which carry Plasmodium in their salivary glands, were not considered primary malaria vectors in India. An. vagus mosquitoes are zoophilic and physically similar to An. subpictus. We intend to identify An. subpictus and An. vagus mosquito's sister species based on their Interspaced Transcribed Region-2 (ITS2). We isolated the midgut gDNA from each mosquito and used ITS2-PCR and Sanger sequencing to characterize the mosquito species. BioEdit software aligned the sequences, and MEGA7 built a phylogenetic tree from them. According to this study, the information gathered from these mosquito samples fits the An. subpictus species A form and the An. vagus Indian form. Furthermore, gut microbiome plays an important role in providing nutrients, immunity, and food processing, whereas mosquitoes' midgut microbiota changes their hosts and spreads illnesses. So, we used the Illumina sequencer to look at the gut microbiome diversity of An. subpictus and An. vagus mosquitoes using 16S rRNA-based metagenomic sequencing. Both mosquito species had an abundant phylum of Pseudomonadota (Proteobacteria), Bacillota, Bacteroidota, and Actinomycetota in their gut microbiomes. Notably, both mosquito species had the genus Serratia in their gut. In the subpictus midgut, the genus of Haematosprillum bacteria was dominant, whereas in the vagus mosquito, the genus of Salmonella was dominant. Notably, current research has observed the Sodalis spp. Bacterial genus for the first time.

RevDate: 2024-10-30

Zhang Y, Cai Z, Wu Z, et al (2024)

Effects of flotation reagents with aniline aerofloat and ammonium dibutyl dithiophosphate on a constructed rapid infiltration system: Performance and microbial metabolic pathways.

Environmental pollution (Barking, Essex : 1987) pii:S0269-7491(24)01935-3 [Epub ahead of print].

Aniline aerofloat (AAF) and ammonium dibutyl dithiophosphate (ADD) are the key flotation reagents in mineral processing. This study investigated the performance of the constructed rapid infiltration systems with coke and red mud as adsorbents for treatment AAF and ADD wastewater. Meanwhile, the effects of AAF and ADD on the microbial metabolic pathways of the systems were unraveled. Results showed that the AAF concentration in influent was 25 mg/L, which promoted chemical oxygen demand (COD) and total phosphorus (TP) removal of the A column (coke) and B column (red mud). While the COD and TP removal of the C column (coke) and D column (red mud) were inhibited with ADD concentration increasing to 50 mg/L and 100 mg/L. The AAF reduced the binding energy of coke C-O bond by 0.9 eV, and down-regulated the C-C bond ratio by 40.72%. The dominant phyla in the columns were Pseudomonadota and Actinomycetota. The pore structure of coke was more conducive to the growth of the Pseudomonadota, while the metal composition of red mud was more conducive to the redox reaction of microorganisms. The presence of phosphofructokinase (2.7.1.11)-related genes was up-regulated in column C compared to other columns. The ADD was beneficial to the expression of norC and nosZ functional genes during nitrogen metabolism process. In contrast, phosphorus metabolism genes were more expressed in the red mud column for treatment AAF wastewater. This study reveals the potential of coke and red mud for the treatment of flotation reagents wastewater, while providing a theoretical basis for the optimal selection of filler types in the constructed rapid infiltration systems.

RevDate: 2024-10-30

Shu Q, Gao H, Li RJ, et al (2024)

The source and dissemination of ARGs in pristine environments: Elucidating the role of migratory birds in the Arctic.

Journal of hazardous materials, 480:136272 pii:S0304-3894(24)02851-6 [Epub ahead of print].

Antibiotic resistance genes (ARGs) are a class of emerging contaminants that significantly threaten public health. In this work, the profiles of ARGs and microbial communities in the soil, sediment, migratory bird, and local deer fecal samples collected from the Arctic were characterized using a metagenomic approach. The results retrieved the baseline profiles of ARGs and identified the role of migratory birds in disseminating ARGs in the Arctic. A total of 26 ARG types and 718 subtypes were determined, and 131 core ARGs were identified. All the samples were dominated by multidrug resistance genes, and some genes resistant to antibiotics commonly used in anthropogenic were also detected. Characterization of ARGs in bird fecal samples was significantly distinct from other media, with higher abundance, richness, and unique ARGs detected. Proteobacteria was the most predominant phylum in soil and fecal samples, while Thaumarchaeota was prevalent in sediment samples. Firmicutes harbored the majority of ARGs in all samples. The results of FEAST indicated that migratory birds were crucial allochthonous ARG sources in the Arctic. These significant findings shed light on the global spread of ARGs and should facilitate efforts to map baseline levels of ARGs before the era of antibiotics.

RevDate: 2024-10-30
CmpDate: 2024-10-30

Khan FZA, Ahmed S, AM Powell (2024)

Vaginal Microbiome and the Risk of Preterm Birth in Women Living With HIV: A Scoping Review.

American journal of reproductive immunology (New York, N.Y. : 1989), 92(5):e70011.

There are sparse data on the role of the vaginal microbiome (VMB) in pregnancy among pregnant women living with HIV (PWLWH) and its association with spontaneous preterm birth (sPTB). We conducted a scoping review to assess associations between vaginal microbiota and sPTB among PWLWH. Three studies were included, representing a total of 180 PWLWH out of 652 total pregnancies. All studies used modern DNA sequencing methods (16S rRNA amplification, metagenomics, or metatranscriptomics). PWLWH had higher VMB richness and diversity compared to HIV-uninfected pregnant women and higher sPTB rates in two of three studies. A higher proportion of sPTB among PWLWH was observed in those with Lactobacillus-deficient, anaerobe-dominant vaginal microbiota. In two of three studies, higher concentrations of vaginal inflammation markers were associated with increased VMB richness and diversity. HIV status was independently associated with sPTB. It is unclear if increased vaginal microbial diversity among PWLWH or increased vaginal inflammation contributes more to PTB, but HIV does appear to alter the VMB in pregnant individuals and may also affect PTB rates in microbiome-independent pathways. Given the limited number of studies, heterogeneity in sample size, sample collection methods, and inconsistent results it is difficult to causally link HIV, VMB, inflammatory cytokines, and sPTB.

RevDate: 2024-10-30
CmpDate: 2024-10-30

Liu S, Ren J, Li J, et al (2024)

Characterizing the gut microbiome of diarrheal mink under farmed conditions: A metagenomic analysis.

PloS one, 19(10):e0312821 pii:PONE-D-24-12095.

This study aimed to comprehensively characterize the gut microbiota in diarrheal mink. We conducted Shotgun metagenomic sequencing on samples from five groups of diarrheal mink and five groups of healthy mink. The microbiota α-diversity and Kyoto Encyclopedia of Genes and Genomes (KEGG) orthology did not show significant differences between the groups. However, significant differences were observed in microbiota β-diversity and the function of carbohydrate-active enzymes (CAZymes) between diarrheal and healthy mink. Specifically, The relative abundance of Firmicutes was lower, whereas that of Bacteroidetes was higher in diarrheal mink. Fusobacteria were enriched as invasive bacteria in the gut of diarrheal mink compared with healthy mink. In addition, Escherichia albertii was identified as a new bacterium in diarrheal mink. Regarding functions, nicotinate and nicotinamide metabolism and glycoside hydrolases 2 (GH2) family were the enhanced KEGG orthology and CAZymes in diarrheal mink. Furthermore, the diversity and number of antibiotic-resistant genes were significantly higher in the diarrheal mink group than in the healthy group. These findings enhance our understanding of the gut microbiota of adult mink and may lead to new approaches to the diagnosis and treatment of mink diarrhea.

RevDate: 2024-10-30

Sánchez-Terrón G, Martínez R, Freire MJ, et al (2024)

Gastrointestinal fate of proteins from commercial plant-based meat analogs: Silent passage through the stomach, oxidative stress in intestine, and gut dysbiosis in Wistar rats.

Journal of food science [Epub ahead of print].

Plant-based meat analogs (PBMAs) are common ultra-processed foods (UPFs) included in the vegan/vegetarian diets as presumed healthy alternatives to meat and meat products. However, such health claims need to be supported by scientific evidence. To gain further insight into this topic, two commercial UPFs typically sold as meat analogs, namely, seitan (S) and tofu (T), were included in a cereal-based chow and provided to Wistar rats for 10 weeks. A group of animals had, simultaneously, an isocaloric and isoprotein experimental diet formulated with cooked beef (B). In all cases, experimental chows (∼4 kcal/g feed) had their basal protein concentration increased from 14% to 30% using proteins from S, T, or B. Upon slaughter, in vivo protein digestibility was assessed, and the entire gastrointestinal tract (digests and tissues) was analyzed for markers of oxidative stress and untargeted metabolomics. Metagenomics was also applied to assess the variation of microbiota composition as affected by dietary protein. Diets based on PBMAs showed lower protein digestibility than those containing meat and promoted an intense luminal glycoxidative stress and an inflammatory intestinal response. The fermentation of undigested oxidized proteins from T in the colon of Wistar rats likely led to formation of mutagenic metabolites such as p-cresol. The presence of these compounds in the animal models raises concerns about the potential effects of full replacement of meat by certain PBMAs in the diet. Therefore, future research might target on translational human studies to shed light on these findings.

RevDate: 2024-10-30
CmpDate: 2024-10-30

Schrago CG, B Mello (2024)

Challenges in Assembling the Dated Tree of Life.

Genome biology and evolution, 16(10):.

The assembly of a comprehensive and dated Tree of Life (ToL) remains one of the most formidable challenges in evolutionary biology. The complexity of life's history, involving both vertical and horizontal transmission of genetic information, defies its representation by a simple bifurcating phylogeny. With the advent of genome and metagenome sequencing, vast amounts of data have become available. However, employing this information for phylogeny and divergence time inference has introduced significant theoretical and computational hurdles. This perspective addresses some key methodological challenges in assembling the dated ToL, namely, the identification and classification of homologous genes, accounting for gene tree-species tree mismatch due to population-level processes along with duplication, loss, and horizontal gene transfer, and the accurate dating of evolutionary events. Ultimately, the success of this endeavor requires new approaches that integrate knowledge databases with optimized phylogenetic algorithms capable of managing complex evolutionary models.

RevDate: 2024-10-30

Liang Y, Huang Z, Fan S, et al (2024)

Highlight signatures of vaginal microbiota and metabolome contributed to the occurrence and recurrence of vulvovaginal candidiasis.

Microbiology spectrum [Epub ahead of print].

UNLABELLED: Vulvovaginal candidiasis (VVC) is a common vaginal infectious disease caused by Candida. The high recurrence rate of VVC is a great clinical challenge, with recurrent VVC (RVVC) defined as four or more episodes within a year. In this study, we recruited 31 RVVC patients, 28 VVC patients, and 29 healthy women. Vaginal samples were collected for metagenomic and metabolic analysis. RVVC and VVC groups presented similar clinical symptoms, with only a significantly increased incidence of swelling in the VVC group. Vaginal microbiota in VVC/RVVC exhibited a decreased abundance of Lactobacillus and increased bacterial vaginosis-associated bacteria, such as Gardnerella, Prevotella, and Atopobium. Notably, Lactobacillus iners was higher in RVVC, suggesting not all Lactobacillus species are protective. Healthy women showed lower overall microbiota diversity, emphasizing single-species dominance for stability. Glycogen metabolism pathways were enriched in RVVC/VVC, and were correlated with Atopobium vaginae, Prevotella bivia, and Lactobacillus jensenii. Peptidoglycan synthesis pathways, associated with P. bivia, were enriched, with the substrate L-glutamate elevated in RVVC, possibly promoted by L. iners. These findings shed light on potential therapeutic targets for recurrent VVC, contributing to the understanding of the intricate interplay between the metabolism of vaginal microbiome and disease.

IMPORTANCE: This study enhances our knowledge of the vaginal microbiota dynamics and the role of associated metabolites in individuals with vulvovaginal candidiasis (VVC) and recurrent vulvovaginal candidiasis through shotgun sequencing and multi-omics analysis. The relationship between metabolites and vaginal microbiota and disease state was revealed. The accumulation of L-glutamate generated in glycogen metabolism, which is governed by Lactobacillus iners or bacterial vaginosis-associated bacteria, may contribute to the incidence and recurrence of VVC. Such insights have the potential to impact the treatment and prevention strategies for these common yet distressing conditions, potentially leading to targeted therapies and improved patient outcomes.

RevDate: 2024-10-30

Xu Z, Yeoh YK, Tun HM, et al (2024)

Variation in the metagenomic analysis of fecal microbiome composition calls for a standardized operating approach.

Microbiology spectrum [Epub ahead of print].

The reproducibility in microbiome studies is limited due to the lack of one gold-standard operating procedure. The aim of this study was to examine the impact of protocol variations on microbiome composition using metagenomic data sets from a single center. We assessed the variation in a data set consisted of 2,722 subjects, including 9 subcohorts harboring healthy subjects and patients with various disorders, such as inflammatory bowel disease, colorectal cancer, and type 2 diabetes. Two different DNA extraction kits, with or without lyticase, and two sample storage methods were compared. Our results indicated that DNA extraction had the largest impact on gut microbiota diversity among all host factors and sample operating procedures. Healthy subjects matched by age, body mass index, and sample operating methods exhibited reduced, yet significant differences (PERMANOVA, P < 0.05) in gut microbiota composition across studies. The variations contributed by DNA extraction were primarily driven by different recovery efficiency of gram-positive bacteria, e.g., phyla Firmicutes and Actinobacteria. This was further confirmed by a parallel comparison of fecal samples from five healthy subjects and a standard mock community. In addition, the DNA extraction method influenced DNA biomass, quality, and the detection of specific lineage-associated diseases. Sample operating approach and batch effects should be considered for cohorts with large sample size or longitudinal cohorts to ensure that source data were appropriately generated and analyzed. Comparison between samples processed with inconsistent methods should be dealt with caution. This study will promote the establishment of a sample operating standard to enhance our understanding of microbiome and translating in clinical practice.IMPORTANCEThe reproducibility of human gut microbiome studies has been suboptimal across cohorts and study design choices. One possible reason for the disagreement is the introduction of systemic biases due to differences in methodologies. In our study, we utilized microbial metagenomic data sets from 2,722 fecal samples generated from a single research center to examine the extent to which sample storage and DNA extraction influence the quantification of microbial composition and compared this variable with other sources of technical and biological variation. Our research highlights the impact of DNA extraction methods when analyzing microbiome data and suggests that the microbiome profile may be influenced by differences in the extraction efficiency of bacterial species. With metagenomics sequencing being increasingly used in clinical biology, our findings provide insight into the challenges using metagenomics sequencing in clinical diagnostics, where the detection of certain species and its abundance relative to a "healthy reference" is key.

RevDate: 2024-10-30
CmpDate: 2024-10-30

Milesi VP (2024)

Redox Gradient Shapes the Chemical Composition of Peatland Microbial Communities.

Geobiology, 22(6):e70001.

The response of soil carbon to climate change and anthropogenic forcing depends on the relationship between the physicochemical variables of the environment and microbial communities. In anoxic soils that store large amounts of organic carbon, it can be hypothesized that the low amount of catabolic energy available leads microbial organisms to minimize the energy costs of biosynthesis, which may shape the composition of microbial communities. To test this hypothesis, thermodynamic modeling was used to assess the link between redox gradients in the ombrotrophic peatland of the Marcell Experimental Forest (Minnesota, USA) and the chemical and taxonomic composition of microbial communities. The average amino acid composition of community-level proteins, called hereafter model proteins, was calculated from shotgun metagenomic sequencing. The carbon oxidation state of model proteins decreases linearly from -0.14 at 10 cm depth to -0.17 at 150 cm depth. Calculating equilibrium activities of model proteins for a wide range of chemical conditions allows identification of the redox potential of maximum chemical activity. Consistent with redox measurements across peat soils, this model Eh decreases logarithmically from an average value of 300 mV at 10 cm depth, close to the stability domain of goethite relative to Fe[2+], to an average value of -200 mV at 150 cm, within the stability domain of CH4 relative to CO2. The correlation identified between the taxonomic abundance and the carbon oxidation state of model proteins enables predicting the evolution of taxonomic abundance as a function of model Eh. The model taxonomic abundance is consistent with the measured gene and taxonomic abundance, which evolves from aerobic bacteria at the surface including Acidobacteria, Proteobacteria, and Verrumicrobia, to anaerobes at depth dominated by Crenarchaeota. These results indicate that the thermodynamic forcing imposed by redox gradient across peat soils shapes both the chemical and taxonomic composition of microbial communities. By providing a mechanistic understanding of the relationship between microbial community and environmental conditions, this work sheds new light on the mechanisms that govern soil microbial life and opens up prospects for predicting geochemical and microbial evolution in changing environments.

RevDate: 2024-10-30

Barbieri G, Gigliucci F, Brambilla G, et al (2024)

Cross-Cutting Approach for the Characterization of Microbial Emerging Hazards in Agriculture Settings from Circular Economy-Driven Wastewater Streams.

Environment & health (Washington, D.C.), 2(2):68-75.

The recycling of biowaste from municipal wastewater treatment plants (WWTPs) in agriculture represents a circular economy-driven source of water and nutrients to support food system sustainability. However, biowaste may represent the source of emerging hazards of anthropogenic and animal origin that can transfer from agricultural soils to related food production, posing a risk to consumers' health, as in the case of outbreaks due to the consumption of ready-to-eat leafy vegetables contaminated with pathogenic E. coli. From this perspective, we propose a combined strategy based on both classical methods and culture-independent metagenomics approaches to identify microbial hazards relevant to foodborne diseases in WWTP-related biowastes. The virulence genes targeted by real-time PCR, performed before and after the enrichment of the raw samples, may represent a proxy for the viability of pathogens, the presence of which is then confirmed via classical microbiological methods. Bioinformatics analysis of shotgun metagenomic sequences could assess the presence of genes associated with resistance to specific antimicrobials followed by phenotypic confirmation via cultivation of the raw samples in the presence of the predicted molecules. Bacterial 16S rDNA analysis supports biowaste traceability based on their taxonomic composition. This strategy would support a "One Health" Action based on a cross-cutting assessment of emerging food-borne risks along the food chain.

RevDate: 2024-10-30

Wu J, Zhang S, Chen Y, et al (2023)

Associations between Wastewater Microbiome and Population Smoking Rate Identified Using Wastewater-Based Epidemiology.

Environment & health (Washington, D.C.), 1(6):394-404.

Tobacco use is known to cause health damage, partly by changing the mouth, respiratory tract, and gut-related microbiomes. This study aims to identify the associations between the human microbiome detected in domestic wastewater and the population smoking rate. Metagenomic sequencing and a biomarker discovery algorithm were employed to identify microorganisms as potential microbial biomarkers of smoking through wastewater-based epidemiology. Wastewater samples were collected from selected catchments with low and high smoking rates, i.e., 11.2 ± 1.5% and 17.0 ± 1.6%, respectively. Using the linear discriminant analysis effect size (LEfSe) method, Neisseria, Desulfovibrio, Megamonas, Blautia, Fusicatenibacter, Granulicatella and Enterococcus were suggested as potential biomarker microorganisms. A higher abundance of pathogens, including Neisseria, Eikenella and Haemophilus, was associated with the high smoking rate, likely because of their colonization in smoking-disturbed human guts. The identified potential microbial biomarkers reflect the change of the human gut microbiome due to the long-term smoking behavior. The metagenomic analysis also indicates that smoking upregulates microbial gene expression of genetic information processing, environmental information processing, and cell wall peptidoglycan cleavage, while it downregulates amino acid, lipid, and galactose metabolisms. The findings demonstrate the potential of microbial biomarkers for the surveillance of smoking through a wastewater-based epidemiology approach.

RevDate: 2024-10-30

Zhao M, Yang C, Zhu L, et al (2024)

Multiomics Analysis Reveals Significant Disparities in the Oral Microbiota and Metabolites Between Pregnant Women with and without Periodontitis.

Infection and drug resistance, 17:4665-4683.

INTRODUCTION: Our study investigated the disparities and correlations between oral microbiota and metabolites in pregnant patients with and without periodontitis.

METHODS: Subgingival plaque samples from all subjects were collected for shotgun metagenomic sequencing and broad-target metabolomics analysis.

RESULTS: Forty pathogens, including Porphyromonas gingivalis, Fusobacterium nucleatum, Eubacterium saphenum, Gemella morbillorum, Tannerella forsythia, Streptococcus anginosus group, Selenomonas sputigena etc, were significantly enriched in pregnant patients with periodontitis (PPP). Conversely, symbiotic species such as Morococcus cerebrosus, Streptococcus vestibularis, S. salivarius, S. mitis, and S. pneumoniae were significantly more abundant in healthy controls (HCs). A total of 87 predicted functional modules (PFMs) exhibited significant differences between the two groups; eight PFMs showed high enrichment in PPP with involvement of PPP-enriched species within these pathways. The remaining 79 PFMs encompassing ribonucleotide biosynthesis, carbohydrate, and amino acid metabolism were highly abundant in HCs. For oral microbial metabolome, a total of 105 metabolites related to 150 KEGG pathways displayed significant differences between the two groups. Pathways such as pyruvate metabolism, folate biosynthesis, vascular smooth muscle contraction, and AMPK/mTOR signaling pathway along with their associated metabolites were found to be enriched in PPP, while carbohydrate metabolism predominated among HCs. Spearman's rank correlation analysis revealed significant positive associations between species enriched in PPP and metabolites enriched in PPP, but significant negative associations between species enriched in PPP and metabolites enriched in HCs.

DISCUSSION: Our findings provide potential biomarkers for distinguishing periodontitis during pregnancy while offering valuable insights into mechanisms exploration and clinical intervention.

RevDate: 2024-10-30

Dharnidharka VR, Wylie KM, Wylie TN, et al (2024)

The Post-transplant Lymphoproliferative Disorders-Metagenomic Shotgun Microbial Sequencing (PTLD-MSMS) Study Methods and Protocol.

Transplantation direct, 10(11):e1723.

Post-transplant lymphoproliferative disorders (PTLDs) remain a feared complication of transplantation, with significant morbidity and mortality. The oncogenic Epstein-Barr virus (EBV) is a key pathogenic driver in 50%-80% of cases. Numerous prognostic indices, comprising multiple clinical, epidemiological and tumor characteristics, including EBV tumor positivity, do not consistently associate with worse patient survival, suggesting a potential role for EBV genome variants in determining outcome. However, the precision medicine tools for determining if a viral genome variant is pathogenic are very limited compared with human genome variants. Further, targeted studies have not implicated a specific viral etiological agent in EBV-negative PTLD. Using novel cutting-edge technologies, we are extracting viral nucleic acids from formalin-fixed, paraffin-embedded archived, or frozen PTLD tissues or plasma, to test for all vertebrate viruses simultaneously in an unbiased fashion, using metagenomic shotgun sequencing (MSS). We are collecting such samples from multiple transplant centers to address the following specific aims and close the following knowledge gaps: (1) Validate our novel observation that PTLD tissue positivity by MSS for anellovirus (and confirmed by PCR) serves as a biomarker for higher transplant recipient mortality after the diagnosis of PTLD; (2) determine the role of other oncogenic viruses in EBV-negative PTLD by unbiased MSS of multiple viral groupings, confirmed by other techniques; and (3) develop the necessary computational, algorithmic and software analytic tools required to determine association of EBV genome variants with worse presentations or outcomes in PTLD. Study completion will contribute to better patient care and may provide avenues for novel therapies.

RevDate: 2024-10-30
CmpDate: 2024-10-30

Wang Y, Chen J, Ni Y, et al (2024)

Exercise-changed gut mycobiome as a potential contributor to metabolic benefits in diabetes prevention: an integrative multi-omics study.

Gut microbes, 16(1):2416928.

BACKGROUND: The importance of gut microbes in mediating the benefits of lifestyle intervention is increasingly recognized. However, compared to the bacterial microbiome, the role of intestinal fungi in exercise remains elusive. With our established randomized controlled trial of exercise intervention in Chinese males with prediabetes (n = 39, ClinicalTrials.gov:NCT03240978), we investigated the dynamics of human gut mycobiome and further interrogated their associations with exercise-elicited outcomes using multi-omics approaches.

METHODS: Clinical variations and biological samples were collected before and after training. Fecal fungal composition was analyzed using the internal transcribed spacer 2 (ITS2) sequencing and integrated with paired shotgun metagenomics, untargeted metabolomics, and Olink proteomics.

RESULTS: Twelve weeks of exercise training profoundly promoted fungal ecological diversity and intrakingdom connection. We further identified exercise-responsive genera with potential metabolic benefits, including Verticillium, Sarocladium, and Ceratocystis. Using multi-omics approaches, we elucidated comprehensive associations between changes in gut mycobiome and exercise-shaped metabolic phenotypes, bacterial microbiome, and circulating metabolomics and proteomics profiles. Furthermore, a machine-learning algorithm built using baseline microbial signatures and clinical characteristics predicted exercise responsiveness in improvements of insulin sensitivity, with an area under the receiver operating characteristic (AUROC) of 0.91 (95% CI: 0.85-0.97) in the discovery cohort and of 0.79 (95% CI: 0.74-0.86) in the independent validation cohort (n = 30).

CONCLUSIONS: Our findings suggest that intense exercise training significantly remodels the human fungal microbiome composition. Changes in gut fungal composition are associated with the metabolic benefits of exercise, indicating gut mycobiome is a possible molecular transducer of exercise. Moreover, baseline gut fungal signatures predict exercise responsiveness for diabetes prevention, highlighting that targeting the gut mycobiome emerges as a prospective strategy in tailoring personalized training for diabetes prevention.

RevDate: 2024-10-30
CmpDate: 2024-10-30

Martin-Cuadrado AB, Rubio-Portillo E, Rosselló F, et al (2024)

The coral Oculina patagonica holobiont and its response to confinement, temperature, and Vibrio infections.

Microbiome, 12(1):222.

BACKGROUND: Extensive research on the diversity and functional roles of the microorganisms associated with reef-building corals has been promoted as a consequence of the rapid global decline of coral reefs attributed to climate change. Several studies have highlighted the importance of coral-associated algae (Symbiodinium) and bacteria and their potential roles in promoting coral host fitness and survival. However, the complex coral holobiont extends beyond these components to encompass other entities such as protists, fungi, and viruses. While each constituent has been individually investigated in corals, a comprehensive understanding of their collective roles is imperative for a holistic comprehension of coral health and resilience.

RESULTS: The metagenomic analysis of the microbiome of the coral Oculina patagonica has revealed that fungi of the genera Aspergillus, Fusarium, and Rhizofagus together with the prokaryotic genera Streptomyces, Pseudomonas, and Bacillus were abundant members of the coral holobiont. This study also assessed changes in microeukaryotic, prokaryotic, and viral communities under three stress conditions: aquaria confinement, heat stress, and Vibrio infections. In general, stress conditions led to an increase in Rhodobacteraceae, Flavobacteraceae, and Vibrionaceae families, accompanied by a decrease in Streptomycetaceae. Concurrently, there was a significant decline in both the abundance and richness of microeukaryotic species and a reduction in genes associated with antimicrobial compound production by the coral itself, as well as by Symbiodinium and fungi.

CONCLUSION: Our findings suggest that the interplay between microeukaryotic and prokaryotic components of the coral holobiont may be disrupted by stress conditions, such as confinement, increase of seawater temperature, or Vibrio infection, leading to a dysbiosis in the global microbial community that may increase coral susceptibility to diseases. Further, microeukaryotic community seems to exert influence on the prokaryotic community dynamics, possibly through predation or the production of secondary metabolites with anti-bacterial activity. Video Abstract.

RevDate: 2024-10-30
CmpDate: 2024-10-30

Zhu W, Chen J, Sun H, et al (2024)

Identification of a newly discovered virus from Culex and Armigeres mosquitoes in China.

Scientific reports, 14(1):25935.

Mosquito associated virus have always been a significant threat to global health. Metagenomics offers a straightforward and quantitative means to acquire the information of novel virus and has greatly enriched the content of mosquito associated virus databases. During an entomological surveillance for arthropod-borne viruses in China, we identified a previously unrecognized virus from mosquitoes, temporarily named Huajieling virus. In this study, a total of 3,960 mosquitoes were collected and then divided into 91 pools, according to location and species. QRT-PCR and nested PCR were performed to confirm the presence of Huajieling virus. Its genomic features and phylogenetic relationships were further analyzed. Our results showed that Huajieling virus was detected in 7 of the 91 mosquito pools and that the minimum infection rate (MIR) was 0.18% (7/3,960). One complete genome sequence and 2 viral partial sequences were obtained from the Huajieling virus-positive pools. Pairwise distances analysis indicated that these amplified sequences shared high nucleotide identity. Phylogenetic analysis demonstrated that Huajieling virus is most closely related to Wufeng shrew picorna-like virus 43, which belonging to Picornavirales. Further analyses indicated that Huajieling virus is a new member of unclassified Picornavirales, and is intermediate between the family Caliciviridae and Secoviridae in taxonomic status.

RevDate: 2024-10-30

Yuan L, Zhu XY, Lai LM, et al (2024)

Author Correction: Clinical application and evaluation of metagenomic next-generation sequencing in pathogen detection for suspected central nervous system infections.

Scientific reports, 14(1):25984 pii:10.1038/s41598-024-76648-8.

RevDate: 2024-10-30
CmpDate: 2024-10-30

Schmitz D, Zwagemaker F, Nooij S, et al (2024)

Accessible viral metagenomics for public health and clinical domains with Jovian.

Scientific reports, 14(1):26018.

The integration of next-generation sequencing into clinical diagnostics and surveillance initiatives is impeded by the lack of data analysis pipelines that align with privacy legislation and laboratory certification protocols. To address these challenges, we developed Jovian, an open-source, virus-focused, metagenomic analysis workflow for Illumina data. Jovian generates scaffolds enriched with pertinent annotations, including taxonomic classification, combined with metrics needed for quality assessment (coverage depth, average GC content, localization of open reading frames, minority single nucleotide polymorphisms), and incorporates host and disease metadata. Interactive web-based reports with an audit trail are generated. Jovian was employed on four systems, hosted by three institutes, utilizing grid-computers, a high-performance compute singular server, and a Windows10 laptop. All systems yielded identical results with matching MD5sums. Comparison with a commercial online reference tool using viral gastroenteritis samples confirmed the identification of the same pathogens. Jovian provides comparable results to a commercially available online reference tool and generates identical results at different institutes with different IT architectures, proving it is portable and reproducible. Jovian addresses bottlenecks in the deployment of metagenomics within public health and clinical laboratories and has the potential to enhance the breadth of surveillance and testing programs, thereby fostering more effective public health interventions.

RevDate: 2024-10-29

Qi H, Lv J, Liao J, et al (2024)

Metagenomic insights into microalgae-bacterium-virus interactions and viral functions in phycosphere facing environmental fluctuations.

Water research, 268(Pt A):122676 pii:S0043-1354(24)01575-6 [Epub ahead of print].

Despite the ecological and biotechnological significance of microalgae-bacterium symbionts, the response of host-virus interactions to external environmental fluctuations and the role of viruses in phycosphere remain largely unexplored. Herein, we employed algal-bacterial granular sludge (ABGS) with varying light intensity and organic carbon loading to investigate the mechanisms of microalgae-bacterium-virus symbionts in response to environmental fluctuations. Metagenomics revealed that enhanced light intensity decreased the diversity of microalgae, so did the diversity of symbiotic bacteria and viruses. As carbon sources decreased, bacteria prompted horizontal gene transfer in phycosphere by 12.76 %-157.40 %, increased the proportion of oligotrophs as keystone species (0.00 % vs 14.29 %) as well as viruses using oligotrophs as hosts (18.52 % vs 25.00 %). Furthermore, virus-carried auxiliary metabolic genes (AMGs) and biosynthetic gene clusters (BGCs) encoding vitamin B12 synthesis (e.g., cobS), antioxidation (e.g., queC), and microbial aggregation (e.g., cysE). Additionally, phylogenetic and similarity analysis further revealed the evolutionary origin and potential horizontal transfer of the AMGs and BGCs, which could potentially enhance the adaptability of bacteria and eukaryotic microalgae. Overall, our research demonstrates that environmental fluctuations have cascading effects on the microalgae-bacteria-virus interactions, and emphasizes the important role of viruses in maintaining the stability of the phycosphere symbiotic community.

RevDate: 2024-10-29

Yang B, Zhang C, Guan C, et al (2024)

Analysis of the composition and function of rhizosphere microbial communities in plants with tobacco bacterial wilt disease and healthy plants.

Microbiology spectrum [Epub ahead of print].

To explore the factors influencing the occurrence of bacterial wilt, the differences in the physicochemical properties, microbial community composition and function between rhizosphere soil of tobacco plants with bacterial wilt and healthy plants in the tobacco planting area of Fuzhou City, Jiangxi Province were analyzed and compared. The results showed that the rhizosphere soil of diseased tobacco exhibited significantly reduced levels of exchangeable potassium, water-soluble potassium, nitrate nitrogen, total nitrogen and pH, in comparison to the rhizosphere soil of healthy plants. Conversely, the available phosphorus content of the rhizosphere soil of diseased tobacco was significantly increased. The amount of Ralstonia solanacearum in soil was negatively correlated with pH, nitrate nitrogen and total nitrogen, and positively correlated with exchangeable potassium and water-soluble potassium. A total of 43 genera were significantly different between the two groups of rhizosphere soil, of which 24 genera were enriched in the rhizosphere of healthy plants, including Ideonella, Rhizophagus, Rhizobacter, Altererythrobacter and Ignavibacterium associated with plant disease resistance, Thermodesulfovibrio, Syntrophorhabdus, Syntrophus, Chlorobium, Hydrogenophaga and Limnohabitans associated with soil sulfur metabolism, as well as Ignavibacterium, Ideonella, Derxia and Azohydromonas associated with soil nitrogen cycling. Kyoto Encyclopedia of Genes and Genomes functional analysis of the unigenes obtained by metagenomic sequencing also showed that the differential unigenes were significantly enriched in the sulfur metabolism pathway. In addition, the rhizosphere soil of diseased tobacco plants exhibited a higher abundance of antibiotic-producing actinomycetes and an increased load of antibiotic resistance genes compared to that of healthy plants. In general, lower pH value, less content of nitrate nitrogen and total nitrogen, and more content of exchangeable potassium and water-soluble potassium could contribute to onset of bacterial wilt. Twenty-four genera, including Ideonella and Rhizophagus, may construct a healthy microecological network in the rhizosphere of tobacco plants. All these factors may interact with each other to control the development of bacterial wilt. This complicated interaction network needs to be explored further.IMPORTANCEPrevious studies have mainly focused on the differences in microbial species composition between healthy and diseased soils, but the differences in microbial community functions between two types of soil have not been well characterized. In this study, soil samples in diseased and healthy plant rhizospheres were collected for physicochemical property testing and metagenomic sequencing. We focused on analyzing the differences in physicochemical properties and microbial community functions between these soils, as well as the correlation between these factors and pathogen content. The results of this study provide a theoretical basis for further understanding the occurrence of tobacco bacterial wilt in the field.

RevDate: 2024-10-29

Liu X, Lu B, Tang H, et al (2024)

Gut microbiome metabolites, molecular mimicry, and species-level variation drive long-term efficacy and adverse event outcomes in lung cancer survivors.

EBioMedicine, 109:105427 pii:S2352-3964(24)00463-8 [Epub ahead of print].

BACKGROUND: The influence of the gut microbiota on long-term immune checkpoint inhibitor (ICI) efficacy and immune-related adverse events (irAEs) is poorly understood, as are the underlying mechanisms.

METHODS: We performed gut metagenome and metabolome sequencing of gut microbiotas from patients with lung cancer initially treated with anti-PD-1/PD-L1 therapy and explored the underlying mechanisms mediating long-term (median follow-up 1167 days) ICI responses and immune-related adverse events (irAEs). Results were validated in external, publicly-available datasets (Routy, Lee, and McCulloch cohorts).

FINDINGS: The ICI benefit group was enriched for propionate (P = 0.01) and butyrate/isobutyrate (P = 0.12) compared with the resistance group, which was validated in the McCulloch cohort (propionate P < 0.001, butyrate/isobutyrate P = 0.002). The acetyl-CoA pathway (P = 0.02) in beneficial species mainly mediated butyrate production. Microbiota sequences from irAE patients aligned with antigenic epitopes found in autoimmune diseases. Microbiotas of responsive patients contained more lung cancer-related antigens (P = 0.07), which was validated in the Routy cohort (P = 0.02). Escherichia coli and SGB15342 of Faecalibacterium prausnitzii showed strain-level variations corresponding to clinical phenotypes. Metabolome validation reviewed more abundant acetic acid (P = 0.03), propionic acid (P = 0.09), and butyric acid (P = 0.02) in the benefit group than the resistance group, and patients with higher acetic, propionic, and butyric acid levels had a longer progression-free survival and lower risk of tumor progression after adjusting for histopathological subtype and stage (P < 0.05).

INTERPRETATION: Long-term ICI survivors have coevolved a compact microbial community with high butyrate production, and molecular mimicry of autoimmune and tumor antigens by microbiota contribute to outcomes. These results not only characterize the gut microbiotas of patients who benefit long term from ICIs but pave the way for "smart" fecal microbiota transplantation. Registered in the Chinese Clinical Trial Registry (ChiCTR2000032088).

FUNDING: This work was supported by Beijing Natural Science Foundation (7232110), National High Level Hospital Clinical Research Funding (2022-PUMCH-A-072, 2023-PUMCH-C-054), CAMS Innovation Fund for Medical Sciences (CIFMS) (2022-I2M-C&T-B-010).

RevDate: 2024-10-29
CmpDate: 2024-10-29

Buigues J, Viñals A, Martínez-Recio R, et al (2024)

Phylogenetic evidence supporting the nonenveloped nature of hepadnavirus ancestors.

Proceedings of the National Academy of Sciences of the United States of America, 121(45):e2415631121.

Reverse-transcribing animal DNA viruses include the hepadnaviruses, a well-characterized family of small enveloped viruses that infect vertebrates but also a sister group of nonenveloped viruses more recently discovered in fish and termed the nackednaviruses. Here, we describe the complete sequence of a virus found in the feces of an insectivorous bat, which encodes a core protein and a reverse transcriptase but no envelope protein. A database search identified a viral sequence from a permafrost sample as its closest relative. The two viruses form a cluster that occupies a basal phylogenetic position relative to hepadnaviruses and nackednaviruses, with an estimated divergence time of 500 My. These findings may lead to the definition of a "proto-nackednavirus" family and support the hypothesis that the ancestors of hepadnaviruses were nonenveloped.

RevDate: 2024-10-29

Bağcı C, Nuhamunada M, Goyat H, et al (2024)

BGC Atlas: a web resource for exploring the global chemical diversity encoded in bacterial genomes.

Nucleic acids research pii:7848841 [Epub ahead of print].

Secondary metabolites are compounds not essential for an organism's development, but provide significant ecological and physiological benefits. These compounds have applications in medicine, biotechnology and agriculture. Their production is encoded in biosynthetic gene clusters (BGCs), groups of genes collectively directing their biosynthesis. The advent of metagenomics has allowed researchers to study BGCs directly from environmental samples, identifying numerous previously unknown BGCs encoding unprecedented chemistry. Here, we present the BGC Atlas (https://bgc-atlas.cs.uni-tuebingen.de), a web resource that facilitates the exploration and analysis of BGC diversity in metagenomes. The BGC Atlas identifies and clusters BGCs from publicly available datasets, offering a centralized database and a web interface for metadata-aware exploration of BGCs and gene cluster families (GCFs). We analyzed over 35 000 datasets from MGnify, identifying nearly 1.8 million BGCs, which were clustered into GCFs. The analysis showed that ribosomally synthesized and post-translationally modified peptides are the most abundant compound class, with most GCFs exhibiting high environmental specificity. We believe that our tool will enable researchers to easily explore and analyze the BGC diversity in environmental samples, significantly enhancing our understanding of bacterial secondary metabolites, and promote the identification of ecological and evolutionary factors shaping the biosynthetic potential of microbial communities.

RevDate: 2024-10-29

Liu X, Luo Y, Chen X, et al (2024)

Fecal microbiota transplantation against moderate-to-severe atopic dermatitis: A randomized, double-blind controlled explorer trial.

Allergy [Epub ahead of print].

BACKGROUND: Fecal microbiota transplantation (FMT) is a novel treatment for inflammatory diseases. Herein, we assess its safety, efficacy, and immunological impact in patients with moderate-to-severe atopic dermatitis (AD).

METHODS: In this randomized, double-blind, placebo-controlled clinical trial, we performed the efficacy and safety assessment of FMT for moderate-to-severe adult patients with AD. All patients received FMT or placebo once a week for 3 weeks, in addition to their standard background treatments. Patients underwent disease severity assessments at weeks 0, 1, 2, 4, 8, 12, and 16, and blood and fecal samples were collected for immunologic analysis and metagenomic shotgun sequencing, respectively. Safety was monitored throughout the trial.

RESULTS: Improvements in eczema area and severity index (EASI) scores and percentage of patients achieving EASI 50 (50% reduction in EASI score) were greater in patients treated with FMT than in placebo-treated patients. No serious adverse reactions occurred during the trial. FMT treatment decreased the Th2 and Th17 cell proportions among the peripheral blood mononuclear cells, and the levels of TNF-α, and total IgE in serum. By contrast, the expression levels of IL-12p70 and perforin on NK cells were increased. Moreover, FMT altered the abundance of species and functional pathways of the gut microbiota in the patients, especially the abundance of Megamonas funiformis and the pathway for 1,4-dihydroxy-6-naphthoate biosynthesis II.

CONCLUSION: FMT was a safe and effective therapy in moderate-to-severe adult patients with AD; the treatment changed the gut microbiota compositions and functions.

RevDate: 2024-10-29

Toyomane K, Kimura Y, Fukagawa T, et al (2024)

Metagenomic sequencing of CRISPRs as a new marker to aid in personal identification with low-biomass samples.

mSystems [Epub ahead of print].

The high specificity of the human skin microbiome is expected to provide a new marker for personal identification. Metagenomic sequencing of clustered regularly interspaced short palindromic repeats (CRISPRs), which we call metaCRISPR typing, was shown to achieve personal identification accurately. However, the intra-individual variability observed in previous studies, which may be due to poor DNA yields from skin samples, has resulted in non-reproducible results. Furthermore, whether metaCRISPR typing can assist in the forensic human DNA analysis of low-biomass samples, from which the information obtained is insufficient, is unknown. In the present study, we sequenced serially diluted control streptococcal CRISPRs cloned into plasmids to determine the minimum copy number required to obtain reproducible results from metaCRISPR typing. We found that at least 10[2] copies of CRISPRs are necessary to obtain reproducible results. We then analyzed the skin swab samples using both metaCRISPR typing and human DNA typing. When the DNA extracted from the skin swabs was diluted, no information was obtained from six out of eight samples by human DNA typing. On the other hand, beta diversity indices of spacer sequences compared with reference samples were below 0.8 for three out of six samples, for which no information was obtained from human DNA analysis, indicating that the spacers observed in these samples were similar to those in the references. These results indicate that metaCRISPR typing may contribute to the identification of individuals from whom the samples were obtained, even in cases where human DNA yields are insufficient to perform human DNA analysis.IMPORTANCEPrevious studies have developed new personal identification methods utilizing personal differences in the skin microbiome. However, intra-individual diversity of skin microbiome may preclude the application of microbiome-based personal identification. Moreover, no study has compared microbiome-based personal identification and practical human DNA analysis. Here, we revealed that the results of metaCRISPR typing, a previously developed microbiome-based personal identification method, are stable if the copy number of the marker gene is sufficient. We then analyzed the skin swab samples using both metaCRISPR typing and human DNA analysis. Our results indicate that metaCRISPR typing may provide additional information for personal identification using low-biomass samples that cannot be used for conventional human DNA analysis.

RevDate: 2024-10-29

Wu J, Zhong Y, Deng Y, et al (2024)

Sustainable Abiotic-Biotic Dechlorination of Perchloroethene with Sulfidated Nanoscale Zero-Valent Iron as Electron Donor Source.

Environmental science & technology [Epub ahead of print].

Combining organohalide-respiring bacteria with nanoscale zero-valent iron (nZVI) represents a promising approach for remediating chloroethene-contaminated aquifers. However, limited information is available regarding their synergistic dechlorinating ability for chloroethenes when nZVI is sulfidated (S-nZVI) under the organic electron donor-limited conditions typically found in deep aquifers. Herein, we developed a combined system utilizing a mixed culture containing Dehalococcoides (Dhc) and S-nZVI particles, which achieved sustainable dechlorination with repeated rounds of spiking with 110 μM perchloroethene (PCE). The relative abundance of Dhc considerably increased from 5.2 to 91.5% after five rounds of spiking with PCE, as evidenced by 16S rRNA gene amplicon sequencing. S-nZVI corrosion generated hydrogen as an electron donor for Dhc and other volatile fatty acid (VFA)-producing bacteria. Electron balance analysis indicated that 68.1% of electrons from Fe[0] consumed in S-nZVI were involved in dechlorination, and 6.2, 1.1, and 3.2% were stored in formate, acetate, and other VFAs, respectively. The produced acetate possibly served as a carbon source for Dhc. Metagenomic analysis revealed that Desulfovibrio, Syntrophomonas, Clostridium, and Mesotoga were likely involved in VFA production. These findings provide valuable insights into the synergistic mechanisms of biotic and abiotic dechlorination, with important implications for sustainable remediation of electron donor-limited aquifers contaminated by chloroethenes.

RevDate: 2024-10-29
CmpDate: 2024-10-29

Wang J, Li M, Zhu J, et al (2024)

Mycobacterium tuberculosis combine with EBV infection in severe adult meningoencephalitis: a rare case reports and literature review.

Frontiers in cellular and infection microbiology, 14:1361119.

BACKGROUND: Tuberculous meningitis (TBM) with adults Epstein-Barr (EB) virus encephalitis is a very rare infectious disease, with a high mortality and disability. Metagenomic next-generation sequencing (mNGS) of cerebrospinal fluid (CSF) is highly diagnostic. We report on a case of severe meningoencephalitis caused by co-infection with mycobacterium tuberculosis and EB virus. Brain MRI indicated a parenchyma lesion in the brain. mNGS of CSF indicated Mycobacterium tuberculosis and EB virus amplification, positive serum EB virus IgG antibodies, and improved symptoms after anti-tuberculosis and antiviral treatment. A re-examination of the brain MRI revealed that the significantly absorption of the lesions.

CASE REPORT: A 49-year-old male patient presented with a chief complaint of headache and fever with consciousness disturbance. The brain magnetic resonance imaging showed a lesions in the right parenchymal brain with uneven enhancement, accompanied by significantly increased intracranial pressure, elevated CSF cell count and protein levels, as well as notably decreased glucose and chloride levels. mNGS of CSF showed the coexistence of Mycobacterium tuberculosis and EBV. The patient was diagnosed as TBM with EBV encephalitis. The patient's symptoms gradually improved with the active administration of anti-tuberculosis combined with antiviral agents, the use of hormones to reduce inflammatory reaction, dehydration to lower intracranial pressure, and intrathecal injection. Subsequent follow-up brain magnetic resonance imaging indicated significant absorption of the lesions, along with a marked decrease in CSF count and protein levels, as well as obvious increase in glucose and chloride levels.

CONCLUSION: TBM associated with adult EBV encephalitis is extremely rare. The disease's early stages are severe and have a high fatality rate. A prompt and accurate diagnosis is particularly important. NGS of CSF is of great value for early diagnosis.

RevDate: 2024-10-29

Wang W, Wang Y, Xin X, et al (2024)

Metagenomic Next-Generation Sequencing Direct Diagnosis of Mixed Bacterial Meningitis in a Child: A Case Report.

Infection and drug resistance, 17:4643-4648.

BACKGROUND: Bacterial meningitis is a major cause of mortality and morbidity in children worldwide. Meanwhile, mixed bacterial meningitis is a rare entity. However, it is difficult to identify anaerobic pathogens using traditional culture methods. Disorders such as neurosurgical interventions are considered risk factors for the development of such cerebral infection. Early diagnosis and appropriate therapy may contribute to patient survival.

CASE PRESENTATION: We report the use of metagenomic next-generation sequencing (mNGS) to facilitate the diagnosis and treatment of polymicrobial meningitis in a 35-month-old male child with a history of detethering procedure for tethered cord syndrome (TCS). The mNGS tests identified six bacterial species from CSF specimens, including four ones of anaerobic bacteria. The subsequent examination of magnetic resonance imaging (MRI) revealed abnormal imaging findings of the lumbosacral area. The patient eventually recovered from severe infections due to long-term antibiotic treatment and radical surgery.

CONCLUSION: This case demonstrates the advantages of mNGS for the rapid and accurate diagnosis of mixed bacterial meningitis, highlighting its application of identifying uncommon pathogens in severe infections. For patients who suffered from exacerbated brain infection with history of detethering surgery, anaerobic cultivation is needed and empiric antibiotic therapy should consider mixed infection in these situations.

RevDate: 2024-10-29
CmpDate: 2024-10-29

Wan Y, Wong OWH, Tun HM, et al (2024)

Fecal microbial marker panel for aiding diagnosis of autism spectrum disorders.

Gut microbes, 16(1):2418984.

Accumulating evidence suggests that gut microbiota alterations influence brain function and could serve as diagnostic biomarkers and therapeutic targets. The potential of using fecal microbiota signatures to aid autism spectrum disorder (ASD) detection is still not fully explored. Here, we assessed the potential of different levels of microbial markers (taxonomy and genome) in distinguishing children with ASD from age and gender-matched typically developing peers (n = 598, ASD vs TD = 273 vs 325). A combined microbial taxa and metagenome-assembled genome (MAG) markers showed a better performance than either microbial taxa or microbial MAGs alone for detecting ASD. A machine-learning model comprising 5 bacterial taxa and 44 microbial MAG markers (2 viral MAGs and 42 bacterial MAGs) achieved an area under the receiving operator curve (AUROC) of 0.886 in the discovery cohort and 0.734 in an independent validation cohort. Furthermore, the identified biomarkers and predicted ASD risk score also significantly correlated with the core symptoms measured by the Social Responsiveness Scale-2 (SRS-2). The microbiome panel showed a superior classification performance in younger children (≤6 years old) with an AUROC of 0.845 than older children (>6 years). The model was broadly applicable to subjects across genders, with or without gastrointestinal tract symptoms (constipation and diarrhea) and with or without psychiatric comorbidities (attention deficit and hyperactivity disorder and anxiety). This study highlights the potential clinical validity of fecal microbiome to aid in ASD diagnosis and will facilitate studies to understand the association of disturbance of human gut microbiota and ASD symptom severity.

RevDate: 2024-10-29

Chero-Sandoval L, Higuera-Gómez A, Martínez-Urbistondo M, et al (2024)

Comparative assessment of phenotypic markers in patients with chronic inflammation: Differences on Bifidobacterium concerning liver status.

European journal of clinical investigation [Epub ahead of print].

BACKGROUND: The relationship between systemic lupus erythematosus (SLE) and low-grade metabolic inflammation (MI) with the microbiota is crucial for understanding the pathogenesis of these diseases and developing effective therapeutic interventions. In this context, it has been observed that the gut microbiota plays a key role in the immune regulation and inflammation contributing to the exacerbation through inflammatory mediators. This research aimed to describe similarities/differences in anthropometric, biochemical, inflammatory, and hepatic markers as well as to examine the putative role of gut microbiota concerning two inflammatory conditions: SLE and MI.

METHODS: Data were obtained from a cohort comprising adults with SLE and MI. Faecal samples were determined by 16S technique. Statistical analyses compared anthropometric and clinical variables, and LEfSe and MetagenomeSeq were used for metagenomic data. An interaction analysis was fitted to investigate associations of microbiota with fatty liver index (FLI) depending on the inflammatory condition.

RESULTS: Participants with low-grade MI showed worse values in anthropometry and biochemicals compared with patients with SLE. The liver profile of patients with MI was unhealthier, while no relevant differences were found in most of the inflammatory markers between groups. LEfSe analysis revealed an overrepresentation of Bifidobacteriaceae family in SLE group. An interactive association between gut Bifidobacterium abundance and type of disease was identified for FLI values, suggesting an effect modification of the gut microbiota concerning liver markers depending on the inflammatory condition.

CONCLUSION: This study found phenotypical and microbial similarities and disparities between these two inflammatory conditions, evidenced in clinical and hepatic markers, and showed the interactive interplay between gut Bifidobacterium and liver health (measured by FLI) that occur in a different manner depending on the type of inflammatory disease. These results underscore the importance of personalized approaches and individual microbiota in the screening of different inflammatory situations, considering unique hepatic and microbiota profiles.

RevDate: 2024-10-29

Papo M, Cappy P, Degachi A, et al (2024)

Lymphadenopathy in systemic lupus erythematosus: no microbial trigger found by shotgun metagenomics in a retrospective study on 38 patients.

Rheumatology (Oxford, England) pii:7848462 [Epub ahead of print].

OBJECTIVES: Lymphadenopathy is a classical manifestation of systemic lupus erythematosus (SLE) flare, occurring in approximately half of patients during the course of the disease. Lymphadenopathy in SLE is frequently associated with fever. Microbial infection may play a role in SLE onset and flares. Objectives of this study were to describe lymphadenopathy in the course of SLE and identify potential infectious triggers using microbial metagenomic analysis.

METHODS: We performed a retrospective monocentric study of 38 patients with SLE who had lymph node biopsy at baseline or during follow-up. Shotgun metagenomics were performed in patient's lymph node biopsy to look for microbial RNA and/or DNA.

RESULTS: Lymph node pathological analyses revealed follicular and/or paracortical hyperplasia 73.7% of patients and histiocytic necrotizing lymphadenitis 23.7%. At the time of biopsy, SLE patients exhibited fever in 29%, splenomegaly in 10%, cutaneous manifestations in 47%, polyarthritis in 32%, seritis in 13% and lupus nephritis in 18%. Half of patients (50%) had increased CRP level, 35% had low C3, 65% had hypergammaglobulinemia. Microbial metagenomic analysis of lymph node biopsy did not reveal the presence of microbial DNA in 92% of patients, the presence of CMV in very small quantities in 2 patients, and the presence of HHV-7 in low quantities in a single patient.

CONCLUSION: Despite suggestion that certain microorganisms may play a role in the pathogenesis and flares of SLE, our microbial metagenomic analysis study did not highlight possible infectious triggering factors. Further and better-designed studies are needed to confirm these results.

RevDate: 2024-10-29
CmpDate: 2024-10-29

Chen Q, Chen Z, Tan Y, et al (2024)

Blood microbiota in HIV-infected and HIV-uninfected patients with suspected sepsis detected by metagenomic next-generation sequencing.

BMC infectious diseases, 24(1):1210.

BACKGROUND: Information on the comparison of blood microbiota between human immunodeficiency virus (HIV)-infected and HIV-uninfected patients with suspected sepsis by metagenomic next-generation sequencing (mNGS) is limited.

METHODS: Retrospectively analysis was conducted in HIV-infected and HIV-uninfected patients with suspected sepsis at Changsha First Hospital (China) from March 2019 to August 2022. Patients who underwent blood mNGS testing were enrolled. The blood microbiota detected by mNGS were analyzed.

RESULTS: A total of 233 patients with suspected sepsis who performed blood mNGS were recruited in this study, including 79 HIV-infected and 154 HIV-uninfected patients. Compared with HIV-uninfected patients, the proportions of mycobacterium (p = 0.001), fungus (p < 0.001) and viruses (p < 0.001) were significantly higher, while the proportion of bacteria (p = 0.001) was significantly lower in HIV-infected patients. The higher positive rates of non-tuberculous mycobacteriosis (NTM, p = 0.022), Pneumocystis jirovecii (P. jirovecii) (p = 0.014), Talaromyces marneffei (T. marneffei) (p < 0.001) and cytomegalovirus (CMV) (p < 0.001) were observed in HIV-infected patients, compared with HIV-uninfected patients. In addition, compared with HIV-uninfected patients, the constituent ratio of T. marneffei (p < 0.001) in the fungus spectrum were significantly higher, while the constituent ratios of Candida (p < 0.001) and Aspergillus (p = 0.001) were significantly lower in HIV-infected patients.

CONCLUSIONS: Significant differences in the blood microbiota profiles exist between HIV-infected and HIV-uninfected patients with suspected sepsis.

RevDate: 2024-10-29
CmpDate: 2024-10-29

Luna N, Páez-Triana L, Ramírez AL, et al (2024)

Microbial community dynamics in blood, faeces and oral secretions of neotropical bats in Casanare, Colombia.

Scientific reports, 14(1):25808.

Bats are known reservoirs for a wide range of pathogenic microorganisms, including viruses, bacteria, fungi, helminths, and protozoa, which can be transmitted and infect other zoonotic organisms. Various studies have utilised next-generation sequencing (NGS) to describe the pathogens associated with bats. Although most have characterised microbial communities in specific body fluids, few have analysed the composition and diversity of these microbial communities across different body fluids at the individual level. In this study, we employed two next-generation sequencing techniques: amplicon-based sequencing of the V4 hypervariable region of the 16S- and 18S-rRNA genes and viral metagenomics, to describe the prokaryotic, eukaryotic, and viral communities present in blood, faeces, and oral swab samples collected from two genera of bats (Carollia and Phyllostomus) in the department of Casanare, eastern Colombia. A total of 60 samples corresponding to the three bodily fluids were processed and analysed. The results indicated that the microbial communities across the body fluids were mainly composed of bacteria, fungi, protozoa, and various DNA and RNA viruses, showing a variability of microbial genera and species. The abundances, diversity metrics, and correlations of these microorganisms displayed patterns associated with bat genus and body fluids, suggesting that the ecological characteristics of these microbial communities may be influenced by the ecological and physiological traits of the bats. Additionally, we found similar community compositions of bacteria, some fungal genera, and viruses in the three body fluids, indicating a possible circulation of these microbes within the same bat. This could be due to microbial movement from the gut microbiota to other physiological systems or transmission via blood-feeding vectors. Furthermore, our results revealed the presence of various microbes of public health concern, including Bartonella spp., Mannheimia haemolytica, Rhodotorula spp., Piroplasmida spp., Toxoplasma gondii, Alphacoronavirus spp., and Bat circovirus. The abundance of these pathogenic microbial species across the three bodily fluids suggests potential transmission routes from bats to other organisms, which may contribute to the emergence of zoonotic disease outbreaks. These findings highlight the variability of microorganisms present within the same bat and the different pathogen-host interactions that may regulate the presence and transmission of these zoonotic microbes. Further research is required to elucidate the genomic features, ecological interactions, and biological activities of these microbial communities in bats.

RevDate: 2024-10-29
CmpDate: 2024-10-29

Słowakiewicz M, Borkowski A, Perri E, et al (2024)

Biofilms in modern CaCO3-supersaturated freshwater environments reveal viral proxies.

Scientific reports, 14(1):25889.

Biofilms are mucilaginous-organic layers produced by microbial activity including viruses. Growing biofilms form microbial mats which enhance sediment stability by binding particles with extracellular polymeric substances and promoting growth through nutrient cycling and organic matter accumulation. They preferentially develop at the sediment-water interface of both marine and non-marine environments, and upon the growing surfaces of modern tufa and travertine. In this context, however, little is known about the factors, environmental or anthropogenic, which affect viral communities in freshwater spring settings. To explore this issue, geochemical and metagenomic data were subjected to multidimensional analyses (Principal Component Analysis, Classical Multidimensional Scaling, Partial Least Squares analysis and cluster analysis based on beta-diversity), and these show that viral composition is specific and dependent on environment. Indeed, waters precipitating tufa and travertine do vary in their geochemistry with their viruses showing distinct variability between sites. These differences between virus groups allow the formulation of a viral proxy, based on the Caudoviricetes/Megaviricetes ratio established on the most abundant groups of viruses. This ratio may be potentially used in analysing ancient DNA preserved in carbonate formations as an additional source of information on the microbiological community during sedimentation.

RevDate: 2024-10-29
CmpDate: 2024-10-29

Saini N, Aamir M, Khan ZA, et al (2024)

Deciphering Toxic Pollutants Breakdown Potential in Microbial Community of Chumathang Hot Spring, Ladakh, India via Shotgun Metagenome Sequencing.

Current microbiology, 81(12):430.

Persistent Organic Pollutants (POPs) have been in focus of research due to their massive contamination of environment and bio-accumulation. Bioremediation and high-throughput research have gained momentum to curb the harmful effects of POPs. The present research has explored the microbial diversity of Chumathang Hot Spring, Ladakh, India, through Illumina metagenomic HiSeq 4000 sequencing platform and their potential to degrade persistent pollutants, especially xenobiotics. Taxonomic characterization based on raw metagenomic data illuminated the abundance of members of Pseudomonadota and Actinomyceota. The re-construction of the microbial genomes from assembled contigs and scaffolds using de novo assembler metaSPAdes and their further annotation through contig alignment with available reference genomes elucidated the landscape of the hot spring's microbes. The predominantly occupied key genera reported were Pannonibacter and Novosphingobium. Comparative genomic analysis established evolutionary relationships and functional diversities among hot spring microbial communities. The function annotation through MG-RAST has revealed their metabolic versatility of degrading a wide array of xenobiotic compounds, including caprolactam, dioxin, chlorobenzene, benzoate, and. Further, the hydroxylating dioxygenase (Saro_3901) was identified as a pivotal component in the aromatic degradation pathways, showcasing extensive metabolic interconnectivity. Interestingly, protein interaction network analysis identified hub genes like Saro_1233 (protocatechuate 4,5-dioxygenase alpha subunit), while Saro_3057 (amidase) was noted for its critical role in network communication and control. The resilience of thermal ecosystems, evidenced by robust enzymatic activity and degradation capability among organisms with < 95% genetic similarity, underscores their potential for industrial and bioremediation exploration, emphasizing the importance of preserving and studying biodiverse habitats.

RevDate: 2024-10-28
CmpDate: 2024-10-28

Wang HM, Zhang MM, Lin Y, et al (2024)

[Characteristics of intestinal microbiota in the acute phase of Kawasaki disease in infants and children].

Zhongguo dang dai er ke za zhi = Chinese journal of contemporary pediatrics, 26(10):1101-1107.

OBJECTIVES: To study the composition, abundance, and functional profiles of the intestinal microbiota in infants and young children with Kawasaki disease (KD) during the acute phase, and to explore the potential role of intestinal microbiota in the pathogenesis of KD.

METHODS: Six children aged 0-3 years with acute KD admitted to the Department of Cardiology, Children's Hospital Affiliated to Capital Institute of Pediatrics from July to October 2021 were prospectively included as the KD group. Six age- and sex-matched healthy children who underwent physical examinations at the hospital during the same period were selected as the healthy control group. Metagenomics sequencing was used to detect and compare the differences in the microflora structure and functional profiles of fecal samples between the two groups.

RESULTS: There were significant differences in the structural composition and diversity of intestinal microbiota between the two groups (P<0.05). Compared with the healthy control group, the abundance of Listeria_monocytogenes (family Listeriaceae and genus Listeria), Bifidobacterium_rousetti, Enterococcus_avium, and Enterococcus_hirae was significantly higher in the intestinal microbiota in the KD group (|LDA|>2.0, P<0.05). The steroid degradation and apoptosis pathways were significantly upregulated in the KD group compared with the healthy control group, while the Bacterial_secretion_system, Sulfur_metabolism, Butanoate_metabolism, Benzoate_degradation, β-alanine metabolism, and α-linolenic acid pathways were significantly downregulated (|LDA|>2, P<0.05).

CONCLUSIONS: There are significant differences in the structure and diversity of intestinal microbiota between children aged 0-3 years with acute KD and healthy children, suggesting that disturbances in intestinal microbiota occur during the acute phase of KD. In particular, Listeria_monocytogenes, Enterococcus_avium, and Enterococcus_hirae may be involved in the pathogenesis of KD through steroid degradation and apoptosis pathways.

RevDate: 2024-10-28
CmpDate: 2024-10-28

Li C, Wang F, Li W, et al (2024)

The diagnostic value of metagenomic next-generation sequencing in critically ill patients with sepsis: A retrospective cohort study.

Medicine, 103(41):e39987.

Metagenomic next-generation sequencing (mNGS) is a new high-throughput sequencing method that may have great importance in early diagnosis and clinical management of sepsis. This study aimed to detect the difference between mNGS and comprehensive routine microbiological test (CMT), and to explore the diagnostic efficacy of mNGS in septic patients. This study retrospectively analyzed 150 sepsis patients who were admitted to the intensive care units of 4 hospitals in Southwest China from October 1, 2018, to October 1, 2021, and underwent both blood mNGS and CMT. The demographic and clinical characteristics of the patients were recorded, and the distribution of pathogens was analyzed. Additionally, the diagnostic performance and concordance between mNGS and CMT were compared to evaluate the etiological diagnostic value of mNGS in sepsis patients. In this study of 150 sepsis patients, bacterial infections were identified in 126 (84.0%), viral in 15 (10.0%), and fungal in 9 (6.0%). Among the sample types, sputum was most common, representing 62% of the total cases. Bronchoalveolar lavage fluid constituted 58.7%, blood 56.0%, with other specimens including pleural fluid at 29.3%, pus at 19.3%, swabs at 9.3%, cerebrospinal fluid at 8.7%, tissue at 6.0%, and bone marrow at 5.3%. mNGS demonstrated a diagnostic accuracy of 56.0% for sepsis, with a sensitivity of 84.4%, specificity of 26.0%, a positive predictive value of 54.6%, a negative predictive value of 61.3%. Metagenomic testing enables the rapid and early identification of infectious pathogens in sepsis patients, especially fungi and viruses. The study found that mNGS has high sensitivity in diagnosing sepsis patients, particularly for fungal and viral infections. mNGS technology is beneficial for critically ill sepsis patients.

RevDate: 2024-10-28
CmpDate: 2024-10-28

Xiao X, Singh A, Giometto A, et al (2024)

Segatella clades adopt distinct roles within a single individual's gut.

NPJ biofilms and microbiomes, 10(1):114.

Segatella is a prevalent genus within individuals' gut microbiomes worldwide, especially in non-Western populations. Although metagenomic assembly and genome isolation have shed light on its genetic diversity, the lack of available isolates from this genus has resulted in a limited understanding of how members' genetic diversity translates into phenotypic diversity. Within the confines of a single gut microbiome, we have isolated 63 strains from diverse lineages of Segatella. We performed comparative analyses that exposed differences in cellular morphologies, preferences in polysaccharide utilization, yield of short-chain fatty acids, and antibiotic resistance across isolates. We further show that exposure to Segatella isolates either evokes strong or muted transcriptional responses in human intestinal epithelial cells. Our study exposes large phenotypic differences within related Segatella isolates, extending this to host-microbe interactions.

RevDate: 2024-10-28
CmpDate: 2024-10-28

Premsuriya J, Leerach N, Laosena P, et al (2024)

The effects of livestock grazing on physicochemical properties and bacterial communities of perlite-rich soil.

PeerJ, 12:e18433.

Livestock grazing has been proposed as a cost-effective way to reclaim post-mining lands. It can enhance soil fertility and biodiversity, but its impacts on soil quality and microbial communities vary across soil types. Moreover, waste from grazing raises concerns about pathogens that could pose risks to animal and human health. This study investigated the effects of grazing on post-mining perlite-rich soil in central Thailand. A comparative analysis of soil physicochemical properties and bacterial diversity was conducted between grazed and ungrazed sites. Bacterial diversity was assessed using 16S amplicon sequencing. The perlite-rich soil was found to be sandy, acidic, and to have low nutritional content. Grazing significantly improved the soil texture and nutrient content, suggesting its potential as a cost-effective reclamation strategy. The 16S metagenomic sequencing analysis revealed that microbial communities were impacted by livestock grazing. Specifically, shifts in the dominant bacterial phyla were identified, with increases in Firmicutes and Chloroflexi and a decrease in Actinobacteria. Concerns about increased levels of pathogenic Enterobacteriaceae due to grazing were not substantiated in perlite-rich soil. These bacteria were consistently found at low levels in all soil samples, regardless of livestock grazing. This study also identified a diverse population of Streptomycetaceae, including previously uncharacterized strains/species. This finding could be valuable given that this bacterial family is known for producing antibiotics and other secondary metabolites. However, grazing adversely impacted the abundance and diversity of Streptomycetaceae in this specific soil type. In line with previous research, this study demonstrated that the response of soil microbial communities to grazing varies significantly depending on the soil type, with unique responses appearing to be associated with perlite-rich soil. This emphasizes the importance of soil-specific research in understanding how grazing affects microbial communities. Future research should focus on optimizing grazing practices for perlite-rich soil and characterizing the Streptomycetaceae community for potential antibiotic and secondary metabolite discovery. The obtained findings should ultimately contribute to sustainable post-mining reclamation through livestock grazing and the preservation of valuable microbial resources.

RevDate: 2024-10-28

Yao Y, Zhao H, Lu H, et al (2024)

Crescentic Glomerulonephritis and Portal Hypertension with Chronic Q Fever: A Case Report and Comprehensive Literature Review.

Infection and drug resistance, 17:4599-4605.

Q fever, an infectious zoonotic disease caused by Coxiella burnetii, remains prevalent in China. Systemic infections can result in renal or hepatic complications; however, it is rare for both the kidneys and liver to be simultaneously affected. We present a case of a patient who exhibited fever, rapid deterioration in renal function, thrombocytopenia, and severe ascites. Renal biopsy revealed crescentic glomerulonephritis, while liver biopsy demonstrated non-cirrhotic portal hypertension. Metagenomic next-generation sequencing (mNGS) identified the presence of Coxiella burnetii in both venous blood and liver tissue samples. Notably, the patient's renal insufficiency and ascites showed a positive response to treatment for chronic Q fever. These findings provide valuable insights into the limited understanding of kidney and liver diseases associated with Q fever. Advanced diagnostic technologies, including mNGS and positron emission tomography/computed tomography (PET/CT), have been employed to identify Coxiella burnetii infection.

RevDate: 2024-10-28

Ostos I, Flórez-Pardo LM, C Camargo (2024)

A metagenomic approach to demystify the anaerobic digestion black box and achieve higher biogas yield: a review.

Frontiers in microbiology, 15:1437098.

The increasing reliance on fossil fuels and the growing accumulation of organic waste necessitates the exploration of sustainable energy alternatives. Anaerobic digestion (AD) presents one such solution by utilizing secondary biomass to produce biogas while reducing greenhouse gas emissions. Given the crucial role of microbial activity in anaerobic digestion, a deeper understanding of the microbial community is essential for optimizing biogas production. While metagenomics has emerged as a valuable tool for unravelling microbial composition and providing insights into the functional potential in biodigestion, it falls short of interpreting the functional and metabolic interactions, limiting a comprehensive understanding of individual roles in the community. This emphasizes the significance of expanding the scope of metagenomics through innovative tools that highlight the often-overlooked, yet crucial, role of microbiota in biomass digestion. These tools can more accurately elucidate microbial ecological fitness, shared metabolic pathways, and interspecies interactions. By addressing current limitations and integrating metagenomics with other omics approaches, more accurate predictive techniques can be developed, facilitating informed decision-making to optimize AD processes and enhance biogas yields, thereby contributing to a more sustainable future.

RevDate: 2024-10-28

Wang L, Wen D, Qu Y, et al (2024)

Case report: A case of cutaneous anthrax guided by metagenomic next-generation sequencing technology.

Frontiers in medicine, 11:1440130.

Anthrax is an acute zoonotic infectious disease caused by Bacillus anthracis. It is categorized as a Class B (reported within 24 h of onset, including pulmonary anthrax, which is managed as a Class A infectious disease and reported within 2 h of onset) infectious disease in China. Human anthrax infection primarily occurs through direct or indirect contact with infected animals. This study reports a case of cutaneous anthrax where typical anthrax colonies were observed in conventional microbial cultures, and large Gram-positive rods with squared ends were visible under the microscope. The results from metagenomic next-generation sequencing (mNGS) suggested the presence of Bacillus anthracis. This research explores the value of combining traditional microbiology with mNGS technology for the early diagnosis and therapy of infectious diseases.

RevDate: 2024-10-28

Thomy J, Schvarcz CR, McBeain KA, et al (2024)

Eukaryotic viruses encode the ribosomal protein eL40.

Npj viruses, 2(1):51.

Viruses in the phylum Nucleocytoviricota are large, complex and have an exceptionally diverse metabolic repertoire. Some encode hundreds of products involved in the translation of mRNA into protein, but none was known to encode any of the proteins in ribosomes, the central engines of translation. With the discovery of the eL40 gene in FloV-SA2, we report the first example of a eukaryotic virus encoding a ribosomal protein and show that this gene is also present and expressed in other uncultivated marine giant viruses. FloV-SA2 also encodes a "group II" viral rhodopsin, a viral light-activated protein of unknown function previously only reported in metagenomes. FloV-SA2 is thus a valuable model system for investigating new mechanisms by which viruses manipulate eukaryotic cell metabolism.

RevDate: 2024-10-27
CmpDate: 2024-10-27

Boutouchent N, Vu TNA, Landraud L, et al (2024)

Urogenital colonization and pathogenicity of E. Coli in the vaginal microbiota during pregnancy.

Scientific reports, 14(1):25523.

This study explores the role of the vaginal microbiota (VM) in the pathophysiology of asymptomatic bacteriuria (ASB) in a cohort of 1,553 pregnant women. Worldwide, E. coli remains the most common etiological agent of bacteriuria during pregnancy and also a major causative agent of newborn infections. A healthy VM is typically characterized by low diversity and is dominated by lactic acid-producing species, notably those from the Lactobacillus genus. Our results point to decreases in Lactobacillus spp associated with an increase of gut-microbiota-associated species from the Enterobacterales order. Escherichia coli exhibited the most pronounced increase in abundance within the VM during bacteriuria and was notably associated with ASB. Molecular typing and antimicrobial resistance characterization of 72 metagenome assembled E. coli genomes (MAGs) from these pregnant women revealed a genomic signature of extraintestinal pathogenic E. coli ("ExPEC") strains, which are involved in various extraintestinal infections such as urinary tract infections, newborn infections and bacteremia. Microbial diversity within the vaginal samples from which an E. coli MAG was obtained showed a substantial variation, primarily marked by a decrease in abundance of Lactobacillus species. Overall, our study shows how disruption in key bacterial group within the VM can disrupt its stability, potentially leading to the colonization by opportunistic pathogens.

RevDate: 2024-10-27
CmpDate: 2024-10-27

Siallagan ZL, Fadli M, de Fretes CE, et al (2024)

Metagenomic analysis of deep-sea bacterial communities in the Makassar and Lombok Straits.

Scientific reports, 14(1):25472.

The extreme conditions of the deep-sea environment, including limited light, low oxygen levels, high pressure, and nutrient scarcity, create a natural habitat for deep-sea bacteria. These remarkable microorganisms have developed unique strategies to survive and adapt to their surroundings. However, research on the diversity of deep-sea bacteria, both culture-dependent and culture-independent, in Indonesian waters remains insufficient. This study focused on exploring the biodiversity of deep-sea bacteria, specifically in the Makassar and Lombok Strait, the main Indonesian throughflow pathway characterized by relatively fertile water, which serves as an important deep-sea region. High-throughput DNA sequencing of full-length 16S rRNA was employed to construct a genomic database. The results of the bioinformatic analysis revealed that two stations, 48 and 50 (Makassar Strait), exhibited a more similar community structure of deep-sea bacteria than did station 33 (Lombok Strait). Among the predominant phyla found at a depth of 1000 m, the top ten were Proteobacteria, Firmicutes, Bacteroidetes, Actinobacteria, Planctomycetes, Acidobacteria, Nitrospinae, Verrucomicrobia, Candidatus Melainabacteria, and Cyanobacteria. Furthermore, the genera Colwellia, Moritella, Candidatus Pelagibacter, Alteromonas, and Psychrobacter consistently appeared at all three stations, albeit with varying relative abundance values. These bacterial genera share common characteristics, such as psychrophilic, halophilic, and piezophilic tendencies, and are commonly found in deep-sea ecosystem. The environmental conditions at a depth of 1000 m were relatively stable, with an average pressure 10 MPa, temperature 4.68 °C, salinity 34.58 PSU, pH 8.06, chlorophyll-a 0.29 µg/L, nitrate 3.19 µmol/L, phosphate 6.32 µmol/L and dissolved oxygen (DO) 2.90 mg/L. The bacterial community structures at the three sampling stations located at the same depth (1000 m) exhibited similarities, as indicated by the closely aligned similarity index values.

RevDate: 2024-10-27
CmpDate: 2024-10-27

Xia J, Yuan Z, F Jiang (2024)

Global metagenomic survey identifies sewage-derived hgcAB[+] microorganisms as key contributors to riverine methylmercury production.

Nature communications, 15(1):9262.

Methylmercury (MeHg) in aquatic systems poses a serious public health risk through bioaccumulation in the aquatic food web. In recent years, MeHg has been observed to increase to concerning levels globally in rivers near cities; however, the causes of this increase are not well understood. Here, we demonstrate the significant role of sewage contamination by analyzing over 1,300 publicly available metagenomes in urban rivers worldwide, and conducting experiments with water samples across China. We find that sewage contamination significantly increases the abundance of mercury (Hg)-methylating microorganisms in urban rivers globally. This increase is primarily attributed to the high abundance of active Hg-methylating microorganisms in sewage, which migrate to rivers via direct discharge or combined sewer overflows (CSOs), becoming key contributors to elevated riverine MeHg levels. Our findings underscore the importance of effectively eliminating Hg-methylating microorganisms from sewage to mitigate the public health risks associated with MeHg in urban rivers.

RevDate: 2024-10-27
CmpDate: 2024-10-27

Gardiner LJ, Marshall M, Reusch K, et al (2024)

DGCNN approach links metagenome-derived taxon and functional information providing insight into global soil organic carbon.

NPJ biofilms and microbiomes, 10(1):113.

Metagenomics can provide insight into the microbial taxa present in a sample and, through gene identification, the functional potential of the community. However, taxonomic and functional information are typically considered separately in downstream analyses. We develop interpretable machine learning (ML) approaches for modelling metagenomic data, combining the biological representation of species with their associated genetically encoded functions within models. We apply our methods to investigate soil organic carbon (SOC) stocks. First, we combine a diverse global set of soil microbiome samples with environmental data, improving the predictive performance of classic ML and providing new insights into the role of soil microbiomes in global carbon cycling. Our network analysis of predictive taxa identified by classical ML models provides context for their ecological significance, extending the focus beyond just the most predictive taxa to 'hidden' features within the model that might be considered less predictive using standard methods for explainability. We next develop unique graph representations for individual microbiomes, linking microbial taxa to their associated functions directly, enabling predictions of SOC via deep graph convolutional neural networks (DGCNNs). Interpretation of the DGCNNs distinguished between the importance of functions of key individual species, providing genome sequence differences, e.g., gene loss/acquisition, that associate with SOC. These approaches identify several members of the Verrucomicrobiaceae family and a range of genetically encoded functions, e.g., related to carbohydrate metabolism, as important for SOC stocks and effective global SOC predictors. These relatively understudied but widespread organisms could play an important role in SOC dynamics globally.

RevDate: 2024-10-26

Jin W, Yu J, Wang H, et al (2024)

Intra/extracellular electron transfer and metagenomic analysis elucidated the roles of magnetic iron powder (Fe3O4) on mixotrophic denitrification system.

Environmental research pii:S0013-9351(24)02144-3 [Epub ahead of print].

Elemental iron provides a viable strategy to improve the denitrification efficiency by expediting electron transport. However, the roles of magnetic iron powder (Fe3O4) on mixotrophic denitrification remains unknown. In this study, the intra/extracellular electron transfer (IET/EET) and microbial metabolism mechanisms were explored in a Fe3O4-mediated sulfide-autotrophic and heterotrophic denitrification system. The results showed that Fe3O4 promoted the formation of dense clump structure with filamentous cross-linking in activated sludge. Fe3O4 could increase the coenzyme Q activity in IET and the content of free riboflavin and cytochrome c in EET. Metagenomic analysis indicated that denitrification, sulfide oxidation and sulfate reduction were the main pathways of nitrogen and sulfur metabolism, and the enriched denitrifying bacteria (Halomonas and Hypobacterium) and sulfur-oxidizing bacteria (Marinicella) could stably support nitrate removal. This study expands our understanding of the IET/EET during Fe3O4-mediated mixotrophic denitrification process, providing a novel insight for nitrogen removal from marine recirculating aquaculture wastewater.

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ESP Quick Facts

ESP Origins

In the early 1990's, Robert Robbins was a faculty member at Johns Hopkins, where he directed the informatics core of GDB — the human gene-mapping database of the international human genome project. To share papers with colleagues around the world, he set up a small paper-sharing section on his personal web page. This small project evolved into The Electronic Scholarly Publishing Project.

ESP Support

In 1995, Robbins became the VP/IT of the Fred Hutchinson Cancer Research Center in Seattle, WA. Soon after arriving in Seattle, Robbins secured funding, through the ELSI component of the US Human Genome Project, to create the original ESP.ORG web site, with the formal goal of providing free, world-wide access to the literature of classical genetics.

ESP Rationale

Although the methods of molecular biology can seem almost magical to the uninitiated, the original techniques of classical genetics are readily appreciated by one and all: cross individuals that differ in some inherited trait, collect all of the progeny, score their attributes, and propose mechanisms to explain the patterns of inheritance observed.

ESP Goal

In reading the early works of classical genetics, one is drawn, almost inexorably, into ever more complex models, until molecular explanations begin to seem both necessary and natural. At that point, the tools for understanding genome research are at hand. Assisting readers reach this point was the original goal of The Electronic Scholarly Publishing Project.

ESP Usage

Usage of the site grew rapidly and has remained high. Faculty began to use the site for their assigned readings. Other on-line publishers, ranging from The New York Times to Nature referenced ESP materials in their own publications. Nobel laureates (e.g., Joshua Lederberg) regularly used the site and even wrote to suggest changes and improvements.

ESP Content

When the site began, no journals were making their early content available in digital format. As a result, ESP was obliged to digitize classic literature before it could be made available. For many important papers — such as Mendel's original paper or the first genetic map — ESP had to produce entirely new typeset versions of the works, if they were to be available in a high-quality format.

ESP Help

Early support from the DOE component of the Human Genome Project was critically important for getting the ESP project on a firm foundation. Since that funding ended (nearly 20 years ago), the project has been operated as a purely volunteer effort. Anyone wishing to assist in these efforts should send an email to Robbins.

ESP Plans

With the development of methods for adding typeset side notes to PDF files, the ESP project now plans to add annotated versions of some classical papers to its holdings. We also plan to add new reference and pedagogical material. We have already started providing regularly updated, comprehensive bibliographies to the ESP.ORG site.

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Papers in Classical Genetics

The ESP began as an effort to share a handful of key papers from the early days of classical genetics. Now the collection has grown to include hundreds of papers, in full-text format.

Digital Books

Along with papers on classical genetics, ESP offers a collection of full-text digital books, including many works by Darwin and even a collection of poetry — Chicago Poems by Carl Sandburg.

Timelines

ESP now offers a large collection of user-selected side-by-side timelines (e.g., all science vs. all other categories, or arts and culture vs. world history), designed to provide a comparative context for appreciating world events.

Biographies

Biographical information about many key scientists (e.g., Walter Sutton).

Selected Bibliographies

Bibliographies on several topics of potential interest to the ESP community are automatically maintained and generated on the ESP site.

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