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PubMed2024

Investigating the degradation potential of microbial consortia for perfluorooctane sulfonate through a functional "top-down" screening approach.

Perfluorooctane sulfonate (PFOS) is a prominent perfluorinated compound commonly found in the environment, known to pose various risks to human health. However, the removal of PFOS presents significant challenges, primarily due to the limited discovery of bacteria capable of effectively degrading PFOS. Moreover, single degradation bacteria often encounter obstacles in individual cultivation and the breakdown of complex pollutants. In contrast, microbial consortia have shown promise in pollutant degradation. This study employed a continuous enrichment method, combined with multiple co-metabolic substrates, to investigate a microbial consortium with the potential for PFOS degradation. By employing this methodology, we effectively identified a microbial consortium that demonstrated the capacity to reduce PFOS when exposed to an optimal concentration of methanol. The consortium predominantly comprised of Hyphomicrobium species (46.7%) along with unclassified microorganisms (53.0%). Over a duration of 20 days, the PFOS concentration exhibited a notable decrease of 56.7% in comparison to the initial level, while considering the exclusion of adsorption effects. Furthermore, by comparing the predicted metabolic pathways of the microbial consortium with the genome of a known chloromethane-degrading bacterium, Hyphomicrobium sp. MC1, using the KEGG database, we observed distinct variations in the metabolic pathways, suggesting the potential role of the unclassified microorganisms. These findings underscore the potential effectiveness of a "top-down" functional microbial screening approach in the degradation of stubborn pollutants.

Fluorocarbons↗
PubMed1984

[Viral-microbial associations and the function of humoral factors of natural immunity in acute pneumonia patients].

A total of 359 patients with acute pneumonia and 152 practically healthy subjects comprising the control group were examined. Immunofluorescence was used to investigate nasopharyngeal washings for detecting antigens of influenza and parainfluenza viruses, respiratory-syncytial virus, adenoviruses, whereas serological studies according to the hemagglutination delay test with diagnostic agents for detecting influenza A1, A2, B, types 1, 2 and 3 parainfluenza, and the complement fixation test were made to detect antibodies against adenoviruses. Serological (65%) and immunofluorescence (63%) studies revealed associations of different viruses: type 3 and 1 parainfluenza, respiratory-syncytial virus (73%) with adenoviruses, influenza B, A2, type 2 parainfluenza. Association of different bacteria was observed in 67% of patients: hemolytic staphylococcus (65%), hemolytic streptococcus (50%), pneumococci (45%), P. aeruginosa (40%), P. mirabilis (35%), E. coli (30%), enterococci (25%). Associations of 3-2 causative agents were predominant (53%). Marked decrease in the content of complement and beta-lysins, elevation of the level of lysozyme were observed in patients with viral-bacterial and viral pneumonias as compared to the same characteristics in patients with bacterial pneumonia and in control group subjects.

Acute Disease↗
PubMed2026

Metagenomic insights into biogeochemical functional potential and resistome dynamics of PM2.5 microbial communities.

Atmospheric particulate matter harbors diverse microorganisms, yet their functional potential in biogeochemical cycling and the associated risks of resistome remain poorly understood. Here, we performed metagenomic sequencing on PM2.5 samples collected across four months to unravel the microbial genetic repertoire involved in methane, nitrogen, phosphorus, and sulfur cycling, as well as the resistome, and pathogen composition. A broad range of functional genes was detected for each biogeochemical cycle, with more than 65% of gene subtypes shared across all months, indicating conserved functional signatures. In contrast, more than 80% of the resistome showed temporal variation in abundance, with the lowest richness observed in March. Temporal shifts were also observed in resistome composition, with several resistance determinants reaching higher abundances in April and May. Network analysis indicated frequent co-occurrence among several pathogenic and opportunistic taxa. Contig-based profiling identified 51 potential pathogenic taxa, including 32 human- or animal-associated taxa. In addition, both PM10 and PM2.5 concentrations were associated with pathogen abundance and functional gene richness (e.g., antibiotic resistance genes and virulence factors). Together, this metagenomic survey suggests contrasting temporal patterns between conserved biogeochemical functional potential and more variable resistome-related traits in PM2.5 microbial communities. While constrained by limited temporal coverage and sample size, this study provides preliminary insights into the ecological and potential public health relevance of airborne microbial communities in urban environments.

Particulate Matter↗
PubMed2026

Comprehensive profiling of antibiotic resistance genes and functional clusters of orthologous groups annotation of gut microbiota in Indonesian Kedu chickens.

Antibiotic resistance is a growing global health concern, with poultry systems acting as important reservoirs of antibiotic resistance genes (ARGs). However, resistome and functional profiles of indigenous chickens raised under traditional systems remain underexplored. This study aimed to characterize the antibiotic resistome, virulence factor genes, and metabolic potential of gut microbiota in Indonesian Kedu chickens using a shotgun metagenomic approach. Digesta samples from five gastrointestinal segments of 21 healthy adult chickens were analyzed through high-throughput sequencing. ARGs were identified using the Comprehensive Antibiotic Resistance Database (CARD) and Antibiotic Resistance Genes Databases (ARDB), while virulence factors and functional genes were annotated using Virulence Factor Database (VFDB), Clusters of Orthologous Groups (COG), and Carbohydrate-Active EnZymes (CAZy) databases. Results revealed a diverse resistome dominated by multidrug resistance and efflux pump mechanisms, with prominent genes associated with fluoroquinolone, tetracycline, β-lactam, and glycopeptide resistance. The detection of clinically relevant ARGs suggests that genetic determinants associated with antimicrobial resistance are present in the gut microbiota of traditionally raised Kedu chickens, although metagenomic data alone cannot determine whether these genes are actively expressed or confer phenotypic resistance. Virulence factor analysis showed functions related to adherence, immune evasion, iron acquisition, quorum sensing, and efflux activity, reflecting strong microbial adaptability. Functional profiling demonstrated enrichment in translation, carbohydrate and amino acid metabolism, genome maintenance, and cell envelope biogenesis. Additionally, CAZyme analysis indicated a high capacity for complex polysaccharide degradation, supporting efficient utilization of fiber-rich traditional diets. In conclusion, this study provides a comprehensive metagenomic overview of antibiotic resistance and functional potential in Kedu chicken gut microbiota, emphasizing the importance of incorporating indigenous poultry into antimicrobial resistance surveillance within a One Health framework.

Antibiotic resistance genes↗
PubMed2026

Evaluation of Indigenous Bacillus Strains from Asian Fermented Foods for Probiotic Properties.

Bacillus species hold particular importance due to their versatile enzymatic repertoire and ability to synthesize diverse bioactive metabolites. In this study, two fermented food-derived strains, Bacillus siamensis BB3 (from douchi) and Bacillus velezensis TMA10 (from tapai) were evaluated for their probiotic, anti-microbial and functional potentials. Both strains exhibited desirable probiotic characteristics, including desirable tolerance to simulated gastric and intestinal conditions, with BB3 showing greater acid tolerance than TMA10. Safety assessments confirmed the absence of hemolytic activity, virulence factors and antibiotic resistance genes. Whole genome sequencing showed that the strains harbored genomic sequences for a wide range of metabolites, including non-ribosomal peptides and polyketides. Ethyl acetate (EtOAc) extracts from both strains demonstrated broad-spectrum anti-microbial activity against several indicator microorganisms, including Listeria grayi, Bacillus cereus, Serratia marcescens, Escherichia coli, and Pseudomonas aeruginosa, with TMA10 additionally inhibiting MRSA and Streptococcus mutans. Liquid Chromatography-Mass Spectrometry profiling identified key anti-microbial compounds, namely surfactins, macrolactins, bacillaene from BB3 and TMA10. In addition, difficidins were also detected from TMA10. Genomic analysis further indicated diverse carbohydrate utilization capacities; both strains encoded pathways for sucrose, raffinose-family oligosaccharides and lactose metabolism, while TMA10 possessed pathways for trehalose, glucomannan and arabinoxylan degradation. Both strains also showed anti-oxidant activity, with enhanced effects observed in their cell-free supernatants and heat-killed preparations. Overall, these findings highlight BB3 and TMA10 as promising candidates for the development of fermented food-derived Bacillus probiotics and functional cultures with anti-microbial, anti-oxidant, and broad carbohydrate-utilization capabilities.

Bacillus↗
PubMed2026

Upcycling Vegetable Waste Into Functional Food Ingredients via Synergistic Microbial Engineering and Artificial Intelligence.

The escalating generation of global vegetable waste represents a critical loss of bioactive resources, necessitating a paradigm shift from passive disposal to active nutrient upcycling. However, the industrial conversion of this heterogeneous biomass into standardized functional food ingredients is currently impeded by significant techno-economic barriers, primarily structural recalcitrance, compositional inconsistency, and the presence of toxic fermentation inhibitors. This review provides a comprehensive analysis of the synergistic application of microbial engineering and artificial intelligence (AI) to resolve these bioprocessing bottlenecks within a food-to-food closed-loop framework (as shown in the graphical abstract). We evaluate recent advances in engineering food-grade microbial chassis (e.g., Saccharomyces cerevisiae and Escherichia coli) to enhance lignocellulose degradation and stress tolerance. Concurrently, we examine the integration of AI across the entire value chain, covering deep learning-based rational enzyme design, genome-scale metabolic modeling, and intelligent process control for precision fermentation. Current evidence demonstrates that the hardware-software coupling of engineered strains and AI algorithms significantly enhances conversion efficiency and process robustness. Key findings highlight that AI-driven Design-Build-Test-Learn cycles facilitate the de novo creation of enzymes with superior kinetics and strains with adaptive stress response capabilities against toxins. Moreover, dynamic digital twin models effectively mitigate the impact of substrate variability, ensuring the batch-to-batch consistency required for food applications. We conclude that this data-driven synergistic paradigm is pivotal for establishing a resilient circular bioeconomy, enabling the reliable bioconversion of waste into high-value single-cell proteins, natural flavor additives, and sustainable packaging materials.

Artificial Intelligence↗
PubMed2025

Roles of microbial interactions in determining the establishment and function of synthetic consortium inoculants for soil applications.

Synthetic microbial consortium inoculants are emerging nature-based solutions for promoting sustainable agriculture and mitigating environmental challenges. However, despite promising results in simpler lab-scale trials, many inoculants fail to establish or perform satisfactorily in field conditions. One most critical yet least understood factor influencing inoculant effectiveness is the complex microbial interactions, both within consortium inoculants ("within-community" interactions) and between consortium inoculants and native soil communities ("cross-community" interactions). Here, we first discuss major negative and positive "within-community" interactions and highlight the importance to design consortium inoculants with positive interactions for improved stability and functionality. We then examine the bidirectional "cross-community" interactions once introducing consortium inoculants to soils. Soil native communities often create strong resistance to the invasion of inoculants. We discuss major drivers controlling the invasibility of native communities and various strategies increasing the invasiveness of consortium inoculants. We then discuss how consortium inoculants can reshape native communities, with implications for long-term ecosystem resilience and functioning. We propose future research efforts including advancing strategies for harnessing natural species from relatively untapped soil reservoirs and using high-throughput interaction profiling with multi-omics and computational tools to build compatible synthetic consortia with desirable functions; leveraging positive interactions and prebiotics to facilitate inoculant establishment; and assessing fully soil functional resilience over longer terms, including recognizing the importance of rare keystone taxa. By integrating with ecological theory, this review provides a comprehensive insight into microbial interactions to advance the design, application, and monitoring of synthetic consortium inoculants for enhancing soil health and ecosystem sustainability.

establishment↗
PubMed2026

Experimental insights in taxon-specific functional responses to droughts in glacier-fed stream biofilms.

BACKGROUND: Glacier-fed streams are predicted to face increasingly frequent and intense droughts. However, the impacts of drought events on benthic biofilm, including bacteria, eukaryotes, and viruses, the dominating life form in glacier-fed streams, remain poorly understood. RESULTS: Using streamside flume mesocosms in the Swiss Alps, we grew glacier-fed stream biofilms over 103 days and exposed them to three droughts. Using a multi-omics approach (metagenomics, metatranscriptomics, and metaproteomics), we assessed the effects of a series of droughts on the taxonomy and metabolic activity of bacterial, eukaryotic, and viral metagenome-assembled genomes (MAGs). We found that the first drought (6 h) caused only minor changes, including mild upregulation of heterotrophic metabolism and signs of stress in diatoms. In contrast, the second drought (24 h) significantly altered both the composition and functionality of the microbiome, shifting phototrophic dominance from diatoms to Cyanobacteriota, while maintaining overall phototropic biomass and further upregulating the heterotrophic metabolism. Interestingly, a third 24 h drought had no detectable transcriptomic effect between pre- and post-drought conditions, suggesting a certain level of adaptive responses to droughts, but with the low diatom abundance being maintained. CONCLUSIONS: These findings indicate that glacier-fed biofilm microorganisms initially resisted short-term drought, but a second longer drought caused important shifts in their community structure, activity, and function. Climate-induced increases in drought frequency or duration may therefore have a lasting impact on microbial ecosystem functioning in glacier-fed streams. Video Abstract.

Biofilms↗
PubMed1986

Relationships between rotavirus diarrhea and intestinal microflora establishment in conventional and gnotobiotic mice.

Intestinal microflora did not play a role in the intensity or course of EDIM rotavirus-induced diarrhea, since similar results were observed in axenic and conventional mice. In conventional mice, rotavirus-induced diarrhea did not modify the establishment of Lactobacillus spp. and Escherichia coli before weaning. The consequences of diarrhea on the establishment of strictly anaerobic bacteria after weaning were studied through the measurement of two bacterial functions, the microbial barrier effect against E. coli and the development of the immunoglobulin A intestinal immune system. These two bacterial functions were expressed in a similar way in diarrheic and control mice. In young gnotobiotic mice inoculated with Clostridium perfringens or C. difficile, rotavirus infection led to an earlier development of both strains, as compared with controls. This effect was more pronounced with C. difficile. These results suggest that rotavirus infections might enhance opportunistic bacterial infections.

Animals↗
PubMed2026

Do Multi-Omics Approaches Improve the Diagnosis of Microbial Overgrowth Syndromes?

PURPOSE OF REVIEW: This review investigates how advances in breath testing (BT), small bowel (SB) culture, metagenomics, metatranscriptomics, transcriptomics and proteomics are reshaping the definition and diagnosis of small intestinal bacterial overgrowth (SIBO). It also discusses whether SIBO should be redefined as part of a larger group of microbial overgrowth syndromes. RECENT FINDINGS: Recent studies identify distinct hydrogen-, methane-, and hydrogen sulfide-associated overgrowth phenotypes, termed SIBO, intestinal methanogen overgrowth (IMO), and intestinal sulfide overproduction (ISO). SB sampling shows that these conditions involve different microbial patterns and functional activity, symptoms, and host responses. Quantitative shotgun metagenomics provides greater taxonomic and functional resolution than culture, while metatranscriptomics reveals active microbial pathways. On top of that, host transcriptomics and proteomics contribute to the better understanding of the predominant microbial effects in host cellular mechanisms in each of the distinct small bowel overgrowth types. SIBO has been increasingly identified as a disorder of microbial ecology and function rather than bacterial quantity alone. Integrating BT with SB sampling and multi-omics approaches may improve classification, clarify symptom mechanisms, and support a more individualized treatment, although standardized methods and further clinical validation remain necessary.

Humans↗
PubMed2026

Programmable in vivo mRNA circularization for enhanced gene expression in bacteria.

The minute-scale lifetime of mRNA strongly influences bacterial gene expression, whereas a robust and programmable approach to directly control the mRNA stability and topology remains elusive. Here, we develop CRESEnT (Circular RNA Expression for Stable and Enhanced Translation), a programmable in vivo mRNA circularization system based on a permuted intron-exon architecture to engineer mRNA topology. CRESEnT enables facile circularization of mRNA, which led to a substantial increase in protein expression across diverse promoters, RBS variants, genetic cargos, and bacterial hosts. Furthermore, application of CRESEnT to biosynthetic pathways increased the production of several value-added metabolites, demonstrating that mRNA circularization can be harnessed to improve the metabolic performance of microbial cell factories. Together, these results establish RNA topology engineering via circularization as a transformative axis for controlling bacterial gene expression and enhancing the functionality of microbial cells.

RNA, Messenger↗
PubMedDate not supplied

Interactions among microorganisms of the indigenous intestinal flora and their influence on the host.

The animal host and its intestinal microbial flora function together as a complex ecologic system in which there is a significant impact of the intestinal flora on the host as well as of components of the microbial flora on one another. Aerobic and anaerobic bacteria of the intestinal flora influence numerous anatomic, physiologic, and immunologic parameters of the host. Constituents of the indigenous intestinal flora also engage in a multitude of antagonistic and cooperative interactions. The normal bacterial intestinal flora represents an extremely important defense mechanism, which effectively interferes with the establishment of many important enteric pathogens. Mechanisms by which microorganisms suppress the growth of other microorganisms include modification of bile acids, stimulation of peristalsis, induction of immunologic responses, depletion of essential substrates from the environment, competition for attachment sites, creation of restrictive physiologic environments, and elaboration of antibiotic-like substances. Components of the intestinal microbial flora also interact synergistically in the induction of disease or the utilization of substrate.

Animals↗
PubMed2025

A deep metagenomic atlas of Qinghai-Xizang Plateau lakes reveals their microbial diversity and salinity adaptation mechanisms.

The Qinghai-Xizang Plateau (QXP), harboring the planet's highest density of plateau lakes, offers an exceptional biogeographic environment for studying extremophilic microbial communities and their adaptation to salinity. Through deep metagenomic sequencing, we construct the Qinghai-Xizang Lake Sediment Genome (QXLSG) catalog, a high-resolution genomic catalog comprising 5,866 metagenome-assembled genomes (MAGs), 58.16 million non-redundant protein encoding genes, and 19,008 biosynthetic gene clusters. Notably, 80.78% of the 2,742 species-level MAGs represent undescribed taxa, significantly expanding the known microbial diversity. Salinity emerges as the primary environmental factor influencing microbial community. Functional annotation highlights that the "salt-out" strategy, particularly the uptake of glycine betaine, is the main mechanism for salinity tolerance. This strategy is prevalent in both hypersaline lake communities and the dominant microbial phyla. Overall, this study provides a crucial genetic resource for future bioprospecting and deepens our understanding of the fundamental mechanisms of microbial adaptation to extreme saline environments.

Lakes↗
PubMed1995

Effect of gamma-irradiation on the effector function of T lymphocytes in microbial control.

A chlamydial-specific T cell clone, capable of inhibiting the growth of infectious Chlamydia in vivo and in vitro, was employed to investigate the effect of gamma-irradiation on the ability of effector T cells to control infections. Clone 2.14-0 (CD4+), specific for the Chlamydia trachomatis biovar agent of mouse pneumonitis (MoPn), was irradiated with varying doses (0, 2.5, 5.0, 10.0, 20.0 and 40.0 Gy) and its biological functions and ability to inhibit the intraepithelial growth of MoPn were assessed. The results revealed that although gamma-irradiation drastically reduced the proliferative response of the clone to antigen, it did not affect the phenotype and the effector function of inhibiting chlamydial growth. The preservation of anti-chlamydial function after gamma-irradiation correlated with the retention of IFN-gamma and TNF-alpha secretion in response to antigenic stimulation. We conclude that the biologic functions of T cells requiring proliferation and differentiation are more likely to be adversely affected by gamma-irradiation on the short-term, but the effector functions, possibly associated with cytokines and cytolysis, may be preserved among persisting effector T cells in an irradiated individual.

Animals↗