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Bibliography on: Biodiversity and Metagenomics

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ESP: PubMed Auto Bibliography 31 May 2025 at 01:30 Created: 

Biodiversity and Metagenomics

If evolution is the only light in which biology makes sense, and if variation is the raw material upon which selection works, then variety is not merely the spice of life, it is the essence of life — the sine qua non without which life could not exist. To understand biology, one must understand its diversity. Historically, studies of biodiversity were directed primarily at the realm of multicellular eukaryotes, since few tools existed to allow the study of non-eukaryotes. Because metagenomics allows the study of intact microbial communities, without requiring individual cultures, it provides a tool for understanding this huge, hitherto invisible pool of biodiversity, whether it occurs in free-living communities or in commensal microbiomes associated with larger organisms.

Created with PubMed® Query: biodiversity metagenomics NOT pmcbook NOT ispreviousversion

Citations The Papers (from PubMed®)

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RevDate: 2025-05-27
CmpDate: 2025-05-26

Guo Y, Lin L, Zhang M, et al (2025)

Salivary mycobiome alterations in HIV-infected MSM: dominance of Pseudogymnoascus and functional shifts across disease stages.

Frontiers in cellular and infection microbiology, 15:1564891.

BACKGROUND: Oral health is increasingly recognized as a crucial determinant of overall health in people living with HIV/AIDS (PLWHA). Specifically, the oral mycobiome may play a pivotal role in HIV-associated oral complications. However, the fungal species involved and their potential as biomarkers for HIV-related oral conditions remain poorly understood. This study investigates salivary fungal profiles in PLWHA who have sex with men (MSM), focusing on diversity, functional shifts, and correlations with disease progression.

METHODS: A cross-sectional study included 25 MSM participants divided into five groups: HIV-negative controls (n = 5) and four HIV-positive groups stratified by CD4 count: Stage 0 (HIV RNA-positive/antibody-negative; n = 5), Stage 1 (CD4 ≥500 cells/μL; n = 5), Stage 2 (CD4 200-499 cells/μL; n = 5), and Stage 3 (CD4 <200 cells/μL or opportunistic infections; n = 5). Saliva samples were collected and analyzed using metagenomic sequencing (Illumina NovaSeq platform). Bioinformatic analyses included genome assembly (MEGAHIT), gene clustering (CD-HIT), gene abundance calculation (SOAPaligner), species annotation (BLASTP), and KEGG pathway annotation (KOBAS 2.0). Statistical analyses (Kruskal-Wallis tests, Spearman's correlation) assessed associations between fungal profiles, CD4 count, and viral loads.

RESULTS: A total of 51 fungal genera were identified, with Pseudogymnoascus being the most abundant. Functional analysis revealed 113 shared KEGG pathways, of which 69 were unique to Stage 3, primarily related to metabolic and disease-related processes. Notably, Auricularia exhibited a positive correlation with CD4 count (P ≤ 0.01), while Mucor showed a negative correlation (P = 0.0299).

CONCLUSIONS: Salivary mycobiome composition and function shift significantly across HIV stages, reflecting immune decline. Pseudogymnoascus dominance challenges conventional views of oral fungal ecology in immunocompromised hosts. These findings highlight the mycobiome's diagnostic potential for monitoring HIV-related oral health. Longitudinal studies are needed to validate clinical relevance.

RevDate: 2025-05-30
CmpDate: 2025-05-25

Rashid MH, Pascottini OB, Xie L, et al (2025)

Shotgun metagenomic composition, microbial interactions and functional insights into the uterine microbiome of postpartum dairy cows with clinical and subclinical endometritis.

Scientific reports, 15(1):18274.

Clinical endometritis (CE) is associated with bacterial pathogens while the same has not been proved about subclinical endometritis (SCE). We aimed to use shotgun metagenomic sequencing to investigate the associations between potentially unidentified pathogens and SCE. Uterine cytobrush samples from multiparous Holstein cows (n = 23) were taken at 21 days in milk (DIM) and sequenced via the Illumina shotgun platform. At 36 DIM, the cows were diagnosed as CE (n = 7), SCE (n = 7), or healthy (n = 9). We did not find differences in the alpha and beta diversity of bacteria and eukaryotes among the health groups. Relative abundance of typical pathogens i.e. Fusobacterium, Peptoniphilus, Peptostreptococcus, and Trueperella was greater in CE than healthy controls. We did not find evidence of eukaryotic or viral association in infection, yet, distinct patterns of bacterial co-occurrence were observed among pathogenic and non-pathogenic bacteria. In CE cows, Wnt/catenin pathway had lower abundance than SCE or healthy cows. Our findings support that CE is characterized by domination of pathogenic bacteria that intercorrelate, whereas SCE is not associated with bacterial colonization.

RevDate: 2025-05-30
CmpDate: 2025-05-25

Thompson TP, Rice CJ, Athanasakis E, et al (2025)

The effect of sample type and location on industrial workplace sink and hand dryer microbiomes.

BMC microbiology, 25(1):325.

One major issue in tackling antimicrobial resistance (AMR) is the ability to effectively track resistance spread in environments where surveillance is limited. Such environments include those experiencing high volumes of hand washing and drying from multiple users. This study characterised the microbial populations and antimicrobial resistomes of two different sample types from a pharmaceutical industrial site as part of an AMR environmental surveillance programme. Paired samples were collected from hand dryers and adjacent sinks in distinct sampling locations: from toilets adjacent to 'wet' labs, and locations associated with 'dry' activities. Microbial populations in hand dryers were significantly different to those of sinks, whereas there was no significant difference based on sample location. The opposite effect was observed for resistomes, where profiles differed significantly based on sample location, but not sample type. When both sample type and location were considered together, differences in microbiomes were driven primarily by hand dryer profiles from different locations. Analysis of metagenomically-assembled genomes revealed the presence of many poorly characterised organisms, and suggested no specific families predominated in terms of ARG carriage. This study emphasises the impact of human activities in determining the resistome of commonly used appliances, and the need for continued AMR surveillance programmes.

RevDate: 2025-05-30
CmpDate: 2025-05-25

Kousgaard SJ, Dall SM, Albertsen M, et al (2025)

Fecal microbiota transplantation from a healthy pouch donor for chronic pouchitis: a proof-of-concept study.

Gut microbes, 17(1):2510464.

Chronic pouchitis is a common complication after ileal pouch-anal anastomosis (IPAA) with limited treatment options. In this case series, we aimed to investigate clinical and microbiome changes, as well as adverse events, associated with using fecal microbiota transplantation (FMT) from a donor with a normal functioning IPAA to induce remission in patients with chronic pouchitis. Methods The study was a case-series including a 4-week intervention period and 12-month follow-up. Patients with chronic pouchitis who met the inclusion criteria were recruited from the Department of Gastrointestinal Surgery at Aalborg University Hospital, Denmark. Participants received FMT derived from a donor with a normal functioning IPAA. Treatment was administered by enema daily for two weeks, then every other day for two more weeks. Disease severity and quality of life (QoL) were accessed at baseline and 30-day follow-up. Clinical remission was defined as Pouchitis Disease Activity Index (PDAI) <7. Fecal samples from participants, healthy donors, and the IPAA donor were analyzed using shotgun metagenomic sequencing. Results Three patients with chronic pouchitis were included and completed the treatment protocol and follow-up visits. At the 30-day follow-up, all participants achieved clinical remission with reduced endoscopic inflammation. The median total PDAI score decreased from 8 (range 10-8) at baseline to 6 (range 6-5) at 30 days. Two participants reported improved QoL, while one reported no change. Few mild, self-limited adverse events were reported by all participants during treatment, with no serious events. Principal component analysis of fecal samples distinguished two clusters: healthy donors and the IPAA donor, with participant samples forming a separate cluster Conclusion We observed that all participants achieved clinical remission with reduced endoscopic inflammation following a 4-week FMT intervention. Adverse events were mild and self-limited. Metagenomic analysis revealed distinct microbiome clusters between IPAA donor and recipients, both of which differed from those of healthy donors.

RevDate: 2025-05-30
CmpDate: 2025-05-30

Ma JY, Liu JH, Chen CZ, et al (2025)

Characteristics of microbial carbon pump in the sediment of kelp aquaculture zone and its contribution to recalcitrant dissolved organic carbon turnover: insights into metabolic patterns and ecological functions.

Environmental research, 277:121559.

The study delves into the microbial carbon pump (MCP) within the sediments of kelp aquaculture zones, focusing on its influence on the turnover of recalcitrant dissolved organic carbon (RDOC). Following kelp harvest, significant alterations in the microbial community structure were noted, with a decrease in complexity and heterogeneity within co-occurrence networks potentially impacting RDOC production efficiency. Metabolic models constructed identified four key microbial lineages crucial for RDOC turnover, with their abundance observed to decrease post-harvest. Analysis of metabolic complementarity revealed that RDOC-degrading microorganisms exhibit broad substrate diversity and are engaged in specific resource exchange patterns, with cross-feeding interactions possibly enhancing the ecological efficiency of the MCP. Notably, the degradation of RDOC was found not to deplete the RDOC pool; as aromatic compounds break down, new ones are released into the environment, thus supporting the renewal of the RDOC pool. The research highlights the pivotal role of microbial communities in RDOC turnover and offers fresh insights into their cross-feeding behavior related to RDOC cycling, providing valuable data to support the future development and application of MCP theory.

RevDate: 2025-05-30
CmpDate: 2025-05-30

Yang X, Yu X, Ming Y, et al (2025)

The vertical distribution and metabolic versatility of complete ammonia oxidizing communities in mangrove sediments.

Environmental research, 277:121602.

Recently discovered complete ammonia-oxidizing (comammox) microorganisms can completely oxidize ammonia to nitrate and play an important role in the nitrogen (N) cycle across various ecosystems. However, little is known about the vertical distribution and metabolic versatility of comammox communities in mangrove ecosystems. Here we profiled comammox communities from deep sediments (up to 5 m) in a mangrove wetland by combining metagenome sequencing and physicochemical properties analysis. Our results showed that the relative abundance of comammox bacteria (23.2 %) was higher than ammonia-oxidizing bacteria (AOB, 12.0 %), but lower than ammonia-oxidizing archaea (AOA, 64.8 %). The abundance of comammox communities significantly (p < 0.01) decreased with the sediment depth, and dissolved organic carbon and total sulfur appeared to be major environmental factors influencing the nitrifying microbial community structure. We also recovered a high-quality metagenome-assembled genome (MAG) of comammox bacteria (Nitrospira sp. bin2030) affiliated with comammox clade A. Nitrospira sp. bin2030 possessed diverse metabolic processes, not only the key genes for ammonia oxidation and urea utilization in the N cycle, but also key genes involved in carbon and energy metabolisms, sulfur metabolism, and environmental adaptation (e.g., oxidative stress, salinity, temperature, heavy metal tolerance). The findings advance our understanding of vertical distribution and metabolic versatility of comammox communities in mangrove sediments, having important implications for quantifying their contribution to nitrification processes in mangrove ecosystems.

RevDate: 2025-05-30
CmpDate: 2025-05-30

Genitsaris S, Stefanidou N, Kourkoutmani P, et al (2025)

Do coastal bacterioplankton communities hold the molecular key to the rapid biodegradation of Polycyclic Aromatic Hydrocarbons (PAHs) from shipping scrubber effluent?.

Environmental research, 277:121563.

Shipping scrubber effluents, containing a cocktail of Polycyclic Aromatic Hydrocarbons (PAHs), show undisputed effects at single-species experiments while PAHs fate in the marine environment after effluent discharge is still investigated. Bacterioplankton, composed of abundant diverse taxa with xenobiotic-degrading capabilities, are the first responders to scrubber emissions and can affect PAHs impacts on marine life. This work aims to examine the fate of scrubber effluent PAHs and alkyl-PAHs in mesocosms of coastal bacterioplankton communities from a pristine (phytoplankton carbon biomass was 8.16 μg C L[-1]) and a eutrophic (105.35 μg C L[-1]) coastal site. High-throughput 16S rRNA metabarcoding revealed differential responses of the bacterioplankton linked to their initial community structure and population abundances. Taxa known for their PAHs-degrading capacity were retrieved, including the genera Roseobacter, Porticoccus, Marinomonas, Arcobacter, Lentibacter, Lacinutrix, Pseudospirillum, Glaciecola, Vibrio, Marivita, and Mycobacterium, and were found to have increased roles in shifted communities by increasing their relative abundances at least 5-fold in treatments with high scrubber effluent additions. Additionally, metagenomic analysis of shotgun sequencing, indicated an increase on the number of Clusters of Orthologous Genes (COGs) associated with pathways involved in PAHs degradation. Up to 198 more COGs involved in signal transduction were retrieved in scrubber effluent enriched mesocosms compared to controls, while 15, 86, and 136 more COGs associated with naphthalene, aromatic compound, and benzoate degradation, respectively, were detected in the pristine mesocosms after effluent additions. In both experiments, bacterioplankton responses towards xenobiotic degradation under increased PAHs and alkyl-PAHs were coupled with a drop in their concentrations, below the limit of detection by Day 3 of the experiment in the eutrophic community, and by half in Day 6 in the pristine environment's community. Our findings indicate that PAHs and alkyl-PAHs impacts can be rapidly reduced in natural systems of high bacterial activity.

RevDate: 2025-05-25
CmpDate: 2025-05-25

Zhang DY, Li D, Chen SJ, et al (2025)

Bacteroides uniformis-generated hexadecanedioic acid ameliorates metabolic-associated fatty liver disease.

Gut microbes, 17(1):2508433.

Gut microbiota exerts a pivotal influence on the development of Metabolic Associated Fatty Liver Disease (MAFLD), although the specific contributions of individual bacterial strains and their metabolites remain poorly defined. We conducted stool shotgun metagenomic sequencing and plasma untargeted metabolomics in a large prospective cohort comprising 120 MAFLD patients and 120 matched healthy controls. The mechanisms and microbial-derived metabolites involved in MAFLD were further investigated through multi-omics analyses in vitro and in vivo. Distinct differences were identified in both the microbial community structure and metabolomic profiles between MAFLD patients and healthy controls. Bacteroides uniformis (B. uniformis) was the most significantly depleted species in MAFLD and negatively correlated with hepatic steatosis and BMI. MAFLD was characterized by marked disruptions in fatty acid and amino acid metabolism. Combined analysis of metabolomic and metagenomic data achieved high diagnostic accuracy for MAFLD and hepatic steatosis severity (AUC = 0.93). Transplantation of fecal microbiota from MAFLD subjects into ABX mice led to the onset of MAFLD-like symptoms, whereas B. uniformis administration alleviate disease progression by inhibiting intestinal fat absorption, FFA from eWAT influx into liver via the gut-liver axis, and IRE1α-XBP1s-mediated flipogenesis and ferroptosis, as confirmed by hepatic transcriptomic and proteomic analyses. Hexadecanedioic acid (HDA), potentially identified as a key metabolite produced by B. uniformis, ameliorated MAFLD symptoms. Mechanistically, B. uniformis-derived HDA also inhibited fat absorption and transported, and entered the liver via the portal vein to suppress IRE1α-XBP1s-mediated flipogenesis and ferroptosis. B. uniformis and its potential putative metabolite HDA may contribute to MAFLD progression modulation, through regulation of the IRE1α-XBP1s axis. This study provides new insights into the gut-liver axis in MAFLD and offers promising therapeutic targets based on specific microbes and their metabolites.

RevDate: 2025-05-27
CmpDate: 2025-05-25

Ju J, He J, Ye B, et al (2025)

Microbial metabolism mediates the deteriorative effects of sedentary behaviour on insulin resistance.

Clinical and translational medicine, 15(5):e70348.

BACKGROUND: Prolonged sedentary time is a strong risk factor for insulin resistance. Recent evidence indicates that gut microbiota may influence the regulation of insulin sensitivity and demonstrates a distinct profile between sedentary and physically active individuals. However, whether and how microbial metabolism mediates the progression of insulin resistance induced by prolonged sedentary time remains unclear.

METHODS: 560 male participants without hypoglycaemic therapy were included, and insulin resistance was evaluated using the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR). The gut microbiota was identified through metagenomics, host genetic data were obtained using a genotyping array, and plasma metabolites were quantified by liquid chromatography mass spectrometry.

RESULTS: A panel of 15 sedentary-related species and 38 sedentary-associated metabolic capacities accounted for 31.68% and 21.48% of the sedentary time-related variation in HOMA-IR, respectively. Specifically, decreased Roseburia sp. CAG:471, Intestinibacter bartlettii, and Firmicutes bacterium CAG:83, but increased Bacteroides xylanisolvens related to longer sedentary time, were causally linked to the development of insulin resistance. Furthermore, integrative analysis with metabolomics identified reduced L-citrulline and L-serine, resulting from a suppression of arginine biosynthesis as key microbial effectors linking longer sedentary time to enhanced insulin resistance.

CONCLUSIONS: In summary, our findings provide insights into the mediating role of gut microbiota on the progression of insulin resistance induced by excessive sedentary time, and highlight the possibility of counteracting the detrimental effect of prolonged sedentary time on insulin resistance by microbiota-modifying interventions.

KEY POINTS: Prolonged sedentary time leads to a depletion of Roseburia sp. CAG:471 and Firmicutes bacterium CAG:83, and suppresses arginine biosynthesis. Decreased L-citrulline and L-serine function as key microbial effectors mediating the adverse effect of sedentary time on insulin sensitivity. Targeting gut microbiota holds promise to combat insulin resistance induced by excessive sedentary time.

RevDate: 2025-05-27
CmpDate: 2025-05-24

Brandão Gontijo J, Huang L, Levintal E, et al (2025)

Depth-dependent Metagenome-Assembled Genomes of Agricultural Soils under Managed Aquifer Recharge.

Scientific data, 12(1):858.

Managed Aquifer Recharge (MAR) systems, which intentionally replenish groundwater aquifers with excess water, are critical for addressing water scarcity exacerbated by demographic shifts and climate variability. To date, little is known about the functional diversity of the soil microbiome at different soil depth inhabiting agricultural soils used for MAR. Knowing the functional diversity is pivotal in regulating nutrient cycling and maintaining soil health. Metagenomics, particularly Metagenome-Assembled Genomes (MAGs), provide a powerful tool to explore the diversity of uncultivated soil microbes, facilitating in-depth investigations into microbial functions. In a field experiment conducted in a California vineyard, we sequenced soil DNA before and after water application of MAR. Through this process, we assembled 146 medium and 14 high-quality MAGs, uncovering a wide array of archaeal and bacterial taxa across different soil depths. These findings advance our understanding of the microbial ecology and functional diversity of soils used for MAR, contributing to the development of more informed and sustainable land management strategies.

RevDate: 2025-05-24
CmpDate: 2025-05-24

Wang C, Tian Z, Luan X, et al (2025)

Distribution of antibiotic resistance genes on chromosomes, plasmids and phages in aerobic biofilm microbiota under antibiotic pressure.

Journal of environmental sciences (China), 156:647-659.

The objective of this study is to quantitatively reveal the main genetic carrier of antibiotic resistance genes (ARGs) for blocking their environmental dissemination. The distribution of ARGs in chromosomes, plasmids, and phages for understanding their respective contributions to the development of antimicrobial resistance in aerobic biofilm consortium under increasing stresses of oxytetracycline, streptomycin, and tigecycline were revealed based on metagenomics analysis. Results showed that the plasmids harbored 49.2 %-83.9 % of resistomes, which was higher (p < 0.001) than chromosomes (2.0 %-35.6 %), and no ARGs were detected in phage contigs under the strict alignment standard of over 80 % identity used in this study. Plasmids and chromosomes tended to encode different types of ARGs, whose abundances all increased with the hike of antibiotic concentrations, and the variety of ARGs encoded by plasmids (14 types and 64 subtypes) was higher than that (11 types and 27 subtypes) of chromosomes. The dosing of the three antibiotics facilitated the transposition and recombination of ARGs on plasmids, mediated by transposable and integrable transfer elements, which increased the co-occurrence of associated and unassociated ARGs. The results quantitatively proved that plasmids dominate the proliferation of ARGs in aerobic biofilm driven by antibiotic selection, which should be a key target for blocking ARG dissemination.

RevDate: 2025-05-29
CmpDate: 2025-05-29

An X, Zhao R, Wang L, et al (2025)

Thiocyanate degradation by mixed bacterial consortia: Adaptive mechanism in response to thiocyanate stress and metabolic pathway.

Environmental research, 278:121688.

Thiocyanate, frequently detected in various industrial wastewater, poses significant risks to organisms. The activated sludge isolate thiocyanate-degrading bacterial consortia (TDBC) efficiently metabolizes thiocyanate. However, the adaptive mechanism in response to thiocyanate stress and metabolic pathway by TDBC have not been elucidated. Metagenomic analysis showed that Thiobacillus (77.73 %) were the primary degraders for the efficient degradation of thiocyanate. A total of 27 genes related to thiocyanate biodegradation were identified, including SCNase, COSase, sulfur oxidation, denitrification and carbon fixation. Metaproteomic revealed the high expression of chemotaxis protein and thioredoxin enhances cellular oxidative stress and maintains normal physiological metabolism. Additionally, the differentially expressed proteins were primarily involved in metabolic pathways including sphingolipid metabolism, energy metabolism, oxidative phosphorylation, two-component system and amino acid metabolism. Then the lipid, organic acid and amino acid metabolism were up-regulated by metabolomic analysis, thereby achieving the degradation of thiocyanate. Using a combination of qRT-PCR and parallel reaction monitoring (PRM), 27 key genes involved in thiocyanate biodegradation have been identified, providing a theoretical basis for developing microbial strategies to mitigate thiocyanate pollution. Molecular docking deepens the understanding of the interaction between degrading enzyme and thiocyanate. This study provides a theoretical basis for the microbial remediation of thiocyanate-containing wastewater.

RevDate: 2025-05-29
CmpDate: 2025-05-29

Chang FM, Chen YH, Hsu PS, et al (2025)

RNA metagenomics revealed insights into the viromes of honey bees (Apis mellifera) and Varroa mites (Varroa destructor) in Taiwan.

Journal of invertebrate pathology, 211:108341.

The honey bee (Apis mellifera) is a vital pollinator for crops. However, they are infested by an ecto-parasite that has spread worldwide, Varroa mite (Varroa destructor). The Varroa mite is a vector of various western honey bee viruses. In this study, the prevalence of seven honey bee viruses (Deformed wing virus, Lake Sinai virus, Acute bee paralysis virus, Sacbrood virus, Kashmir bee virus, Black queen cell virus, Israeli acute paralysis virus), was screened with the honey bees, which were collected from fourteen apiaries from March 2023 to January 2024, and the Varroa mites, which were collected from two apiaries from July to October 2023 by using RT-PCR. Subsequently, metagenomic analyses were conducted on seven honey bee samples and two Varroa mite samples using next-generation sequencing with poly-A capture and rRNA depletion library construction methods. The results showed that 50% to 85.7% of honey bee viruses in each sample were detected by both methods, with up to three additional viruses identified when combining the two approaches. These findings underscore the importance of integrating both methods for comprehensive virome analysis. According to the virome analysis, 28 honey bee viruses were identified in honey bees and 11 in Varroa mites. Among these, 23 viruses were newly recorded in Taiwanese honey bee populations. Notably, three of the newly recorded viruses, Acute bee paralysis virus, Israeli acute paralysis virus, and Apis mellifera filamentous virus, are known to cause symptoms in honey bees, posing potential risks to their health. Six of these viruses were also detected in Varroa mites, highlighting their role in viral transmission. This study represents the first virome analysis of honey bees and Varroa mites in Taiwan, providing critical insights into honey bee health and establishing a foundation for future health assessment indices and mitigation strategies.

RevDate: 2025-05-29
CmpDate: 2025-05-29

Silva CJFD, Silva CVFD, Cardoso AM, et al (2025)

Exploring clinical parameters and salivary microbiome profiles associated with metabolic syndrome in a population of Rio de Janeiro, Brazil.

Archives of oral biology, 175:106251.

OBJECTIVES: This study investigates for the first time the association between metabolic syndrome and oral microbial profiles in a population-based sample from Rio de Janeiro, Brazil.

DESIGN: We assessed 66 volunteers, collecting detailed sociodemographic, anthropometric, and clinical data alongside salivary samples for metagenomic analysis.

RESULTS: Our findings reveal significant differences in anthropometric parameters, including waist circumference, glycemia, High-Density Lipoprotein (HDL), and triglycerides between the metabolic syndrome and control groups. Increased abundance of Bacteroidetes and Bacteroidia was observed in the metabolic syndrome group, suggesting a potential link between these phyla and metabolic dysregulation. While no significant differences in alpha diversity were found between the overall groups, stratification by body mass index (BMI) indicated that the normal weight subgroup without Metabolic Syndrome exhibited notable variations compared to overweight and obese individuals.

CONCLUSIONS: This study identifies specific shifts in oral microbiota composition that are associated with metabolic syndrome, highlighting their potential as microbial biomarkers for this condition. These findings suggest a link between oral dysbiosis and metabolic dysregulation, providing new insights into the pathophysiology of metabolic syndrome. Additionally, the results pave the way for the development of non-invasive diagnostics tools and targeted therapies that leverage the oral microbiome's role in systemic health.

RevDate: 2025-05-25
CmpDate: 2025-05-24

Chu B, Ge S, He W, et al (2025)

Gut symbiotic bacteria enhance reproduction in Spodoptera frugiperda (J.E. Smith) by regulating juvenile hormone III and 20-hydroxyecdysone pathways.

Microbiome, 13(1):132.

BACKGROUND: The insect gut microbiota forms a complex, multifunctional system that significantly affects phenotypic traits linked to environmental adaptation. Strong reproductive potential underpins the migratory success, population growth and destructive impact of the fall armyworm, Spodoptera frugiperda (J.E. Smith). However, the precise role of gut bacteria in S. frugiperda reproductive processes, distribution and transmission dynamics remains unclear.

RESULTS: We examined the gut microbiota of S. frugiperda a major invasive agricultural pest, identifying Enterococcus, Enterobacter, and Klebsiella as core microorganisms present throughout its life cycle. These microbes showed heightened activity during the egg stage, early larval stages and pre-oviposition period in females. Using an axenic insect re-infection system, Enterococcus quebecensis FAW181, Klebsiella michiganensis FAW071 and Enterobacter hormaechei FAW049 were found to significantly enhance host fecundity, increasing egg production by 62.73%, 59.95%, and 56.71%, respectively. Metagenomic and haemolymph metabolomic analyses revealed a positive correlation between gut symbiotic bacteria and hormone metabolism in female S. frugiperda. Further analysis of metabolites in the insect hormone biosynthesis pathway, along with exogenous injection of juvenile hormone III and 20-hydroxyecdysone, revealed that gut microbes regulate these hormones, maintaining levels equivalent to those in control insects. This regulation supports improved fecundity in S. frugiperda, aiding rapid colonization and population expansion.

CONCLUSIONS: These findings emphasize the pivotal role of gut bacteria E. quebecensis FAW181, E. hormaechei FAW049, and K. michiganensis FAW071 in enhancing S. frugiperda reproduction by modulating JH III levels through JHAMT regulation and concurrently modulating the levels of 20E and its precursors via PHM. Our results provide novel insights into microbe-host symbiosis and pest management strategies for alien invasive species. Video Abstract.

RevDate: 2025-05-26
CmpDate: 2025-05-23

Chen AS, Kim H, Nzabarushimana E, et al (2025)

Association of distinct microbial and metabolic signatures with microscopic colitis.

Nature communications, 16(1):4644.

Microscopic colitis (MC) is a chronic inflammatory disease of the large intestine that primarily affects older adults and presents with chronic diarrhea. The etiology is unknown and there are currently no FDA approved medications or biomarkers for treatment or monitoring of the disease. Emerging evidence have implicated the gut microbiome and metabolome disturbances in MC pathogenesis. We conduct a comprehensive analysis of gut microbial and metabolic changes in a cohort of 683 participants, including 131 patients with active MC, 159 with chronic diarrhea, and 393 age- and sex-matched controls without diarrhea. Stool microbiome and metabolome are profiled using whole-genome shotgun metagenomic sequencing and ultra-high performance liquid chromatography-mass spectrometry, respectively. Compared to controls, eight microbial species including pro-inflammatory oral-typical Veillonella dispar and Haemophilus parainfluenzae, and 11 species, including anti-inflammatory Blautia glucerasea and Bacteroides stercoris are enriched and depleted in MC, respectively. Pro-inflammatory metabolites, including lactosylceramides, ceramides, lysophospholipids, and lysoplasmalogens, are enriched in active MC. Multi-omics analyses reveal robust associations between microbial species, metabolic pathways, and metabolites, suggesting concordant disruptions in MC. Here, we show distinct shifts in gut microbiome and metabolome in MC that can inform the development of non-invasive biomarkers and novel therapeutics.

RevDate: 2025-05-23

Su C, Zhou H, Wang Y, et al (2025)

Contrasting Effects of Atmospheric Particulate Matter Deposition on Free-Living and Particle-Associated Bacteria in the South China Sea.

Environmental science & technology [Epub ahead of print].

Atmospheric particulate matter (PM) deposition has become an important nutrient source in marine ecosystems, increasing particulate organic carbon and resource heterogeneity. However, their effects on marine bacterial communities remain unclear. In this study, by conducting on-board microcosm experiments with anthropogenic East Asian PM in the oligotrophic South China Sea, the response of particle-associated (PA) bacteria was investigated and compared with its free-living (FL) counterparts. Results showed that PM input increased nutrient heterogeneity, shifting bacterial community composition and lifestyle. Copiotrophic PA bacteria became more abundant and contributed a disproportionately higher percentage to total bacterial production despite a decline in total bacterial abundance. FL bacteria showed increased diversity, shifting from oligotrophs to copiotrophs, while PA bacteria displayed reduced diversity and nondirectional compositional changes, suggesting their distinct assembly mechanisms in response to external nutrient inputs. Metagenomic analysis further revealed that PM drives a shift toward a copiotrophic, particle-attached lifestyle with upregulated pathways for chemotaxis, motility, and biofilm formation. Notably, PM addition also increased the relative abundance of oil-degrading taxa. These findings reveal the complexity of microbial responses to environmental perturbations and underscore the need to consider unique ecological niches and bacterial lifestyles.

RevDate: 2025-05-23
CmpDate: 2025-05-23

Zhou S, Wang K, Huang J, et al (2025)

Indole-3-lactic acid suppresses colorectal cancer via metabolic reprogramming.

Gut microbes, 17(1):2508949.

Research indicates that abnormal gut microbiota metabolism is linked to colorectal cancer (CRC) progression, but the role of microbiota-related tryptophan metabolism disruption remains unclear. Using metagenomic sequencing and targeted Trp metabolomics, our research identified that CRC patients had abnormal indole-3-lactic acid (ILA) levels, which were related to tumor malignancy. Exogenous ILA administration suppressed CRC development in AOM/DSS induced and xenograft mice models. Furthermore, in vitro experiments demonstrated that ILA inhibits tumor cell proliferation, migration, and anti-apoptotic capabilities. Mechanistically, ILA appears to directly occupy the phosphorylation sites of STAT3, leading to a reduction in intracellular phosphorylated STAT3 (p-STAT3) levels and the inhibition of the HK2 pathway, thereby downregulating glucose metabolism in cancer cells. Notably, this inhibition is independent of the aryl hydrocarbon receptor (AHR). In conclusion, our research findings demonstrate that alterations in tryptophan metabolism among CRC patients can influence tumor progression and reveal a novel mechanism through which ILA exerts its inhibitory effects on CRC. These findings offer new insights into the role of gut microbiota in CRC and identify potential clinical therapeutic targets.

RevDate: 2025-05-23
CmpDate: 2025-05-23

Creskey M, Silva Angulo F, Wu Q, et al (2025)

Metaproteomics reveals age-specific alterations of gut microbiome in hamsters with SARS-CoV-2 infection.

Gut microbes, 17(1):2505117.

The gut microbiome's pivotal role in health and disease is well established. SARS-CoV-2 infection often causes gastrointestinal symptoms and is associated with changes of the microbiome in both human and animal studies. While hamsters serve as important animal models for coronavirus research, there exists a notable void in the functional characterization of their microbiomes with metaproteomics. In this study, we present a workflow for analyzing the hamster gut microbiome, including a metagenomics-derived hamster gut microbial protein database and a data-independent acquisition metaproteomics method. Using this workflow, we identified 32,419 protein groups from the fecal microbiomes of young and old hamsters infected with SARS-CoV-2. We showed age-specific changes in the expressions of microbiome functions and host proteins associated with microbiomes, providing further functional insight into the interactions between the microbiome and host in SARS-CoV-2 infection. Altogether, this study established and demonstrated the capability of metaproteomics for the study of hamster microbiomes.

RevDate: 2025-05-25
CmpDate: 2025-05-23

Song T, Yin L, Zhou X, et al (2025)

Microbiota profiling from biopsied tissues in complex infections: a diagnostic and prognostic analysis through metagenomic next-generation sequencing.

Frontiers in cellular and infection microbiology, 15:1567981.

BACKGROUND: Infectious diseases that require tissue biopsy are usually more difficult to diagnose through conventional microbiological tests (CMT), and knowledge of the infection microbiota pattern from biopsied tissues remains incomplete. Our study aimed to investigate the diagnostic and prognostic value of metagenomic next-generation sequencing (mNGS), characterize the microbiota profile from biopsied tissues, and examine its relationship with clinical outcomes.

METHODS: This retrospective cohort study included 110 patients who underwent tissue biopsy and sent both mNGS and CMT due to suspected complex infection. Microbiota patterns were illustrated via unsupervised hierarchical clustering analysis. Multivariate regression analysis was used to investigate the effect measures.

RESULTS: The sensitivity of mNGS was significantly higher than that of CMT regarding bacteria (87.23% vs 40.43%, P=0.01), viruses (100% vs 5.56%, P<0.001), and fungi (87.5% vs 28.6%, P=0.04). Polymicrobial infection accounted for 45.2% (33/73) of the infection samples. In skeletal articular biopsied tissues, Staphylococcus presented the highest mean abundance among different species of bacteria (21.2% of all bacterial reads, standard deviation (SD) 38.9). Anaerobic bacteria (24.0%, SD 25.9) represented the most common bacteria in biopsied tissue from the lung or mediastinum. The presence of gram-negative bacteria (adjusted OR 5.21, 95% CI 1.39-19.43, P=0.01), Enterobacteriaceae (adjusted OR 5.71, 95% CI 1.17-28.03, P=0.03) and Staphylococcus (adjusted OR 8.64, 95% CI 1.95-38.34, P=0.005) was associated with an increased risk of treatment failure. Early mNGS sampling within 7 days after admission was associated with a significantly decreased risk of all-cause mortality (HR 0.18, 95% CI 0.04-0.94; P=0.04), treatment failure (OR 0.17, 95% CI 0.05-0.66; P=0.01), and increased probability of clinical resolution (OR 3.03, 95% CI 1.24-7.40; P=0.01).

CONCLUSION: mNGS demonstrates significant diagnostic and prognostic efficacy in patients undergoing tissue biopsy for suspected complex infections. The presence of Gram-negative bacteria, Enterobacteriaceae, and Staphylococcus is associated with a higher probability of treatment failure, which underscores the advantage of using mNGS to guide more aggressive antibiotic strategies.

RevDate: 2025-05-25
CmpDate: 2025-05-23

Yasmin A, Rahman MS, Kador SM, et al (2025)

Metagenomic insights into microbial diversity and potential pathogenic transmission in poultry farm environments of Bangladesh.

BMC microbiology, 25(1):318.

The microbiome plays a critical role in poultry health and productivity, influencing growth, immunity, and the overall farm ecosystem. This study investigated microbial diversity, antibiotic resistance pathways, and functional potential across various components of poultry ecosystems-cloacal swabs, droppings, feed, hand swabs, soil, and water-in different districts of Bangladesh. Using 16S rRNA gene amplicon sequencing, we identified 2,745 Operational Taxonomic Units (OTUs) and analyzed microbial richness, community structure, and functional pathways. Alpha diversity metrics revealed that droppings exhibited the highest microbial richness (726 OTUs in Noakhali), while feed samples showed the lowest diversity (211 OTUs). Beta diversity analysis indicated significant differences in microbial composition across sample sources, with PERMANOVA confirming that sample origin accounted for 51.45% of the variability (p < 0.001). Proteobacteria dominated the microbial communities (48.36%), followed by Firmicutes (19.83%) and Cyanobacteria (12.02%). Key genera of concern, such as Enterobacter (26.62% in hand swabs), Acinetobacter (30.87% in cloacal swabs), and Shigella (22.89% in cloacal swabs), were identified, highlighting potential contamination and zoonotic risks. Conversely, beneficial genera like Lactobacillus (36.89% in feed) and Enterococcus (10.78% in droppings) were prevalent, suggesting roles in gut health and nutrient cycling. Functional pathway analysis (KEGG) revealed that carbohydrate and amino acid metabolism were highly active in droppings and feed, reflecting nutrient utilization. Antimicrobial resistance (AMR) pathways, such as 23S rRNA-methyltransferase and multidrug efflux pumps, were widespread, with pathogenic genera (Enterobacter, Acinetobacter, Shigella, Pseudomonas) showing strong positive correlations with AMR pathways. These findings underscore the influence of environmental factors on microbial diversity and functional potential in poultry farming. The study highlights the need for improved management practices and biosecurity measures to mitigate risks associated with microbial pathogens and antimicrobial resistance, ultimately supporting healthier and more sustainable poultry production in Bangladesh.

RevDate: 2025-05-25
CmpDate: 2025-05-22

Li J, Chen Z, Yan X, et al (2025)

Effects of USP25 knockout on the gut microbial diversity and composition in mice.

BMC microbiology, 25(1):315.

BACKGROUND: The gut microbiota plays a crucial role in host health. Recent study revealed that ubiquitin-specific protease 25 (USP25) deficiency affected colonic immune responses and resistance to certain bacterial infection. This study aimed to investigate the impact of USP25 gene deletion on the gut microbiota of mice, utilizing 16 S rRNA amplicon sequencing and metagenomic sequencing to provide a comprehensive analysis of microbial diversity, composition and functional characteristics.

METHODS: We collected fecal samples from 10 wild type (WT) C57BL/6J mice and 10 USP25[-/-] mice (C57BL/6J-Usp25[em1]cyagen) for 16 S rRNA amplicon sequencing. Subsequently, the 6 of the 20 samples underwent further analysis using metagenomic sequencing.

RESULTS: Our results revealed significant differences in the gut microbiota between USP25 knockout (KO) mice and wild-type (WT) controls, with KO mice exhibiting 1,858 unique amplicon sequence variants (ASVs) compared to 1,723 in WT mice. Notably, the KO group displayed a higher tendency for biofilm formation and a greater proportion of gram-negative bacteria, while the WT group demonstrated enhanced stress tolerance and a higher presence of gram-positive bacteria. Functional prediction analyses indicated an increase in antibiotic resistance genes in the KO mice, particularly for tetracycline, cephalosporin, and sulfonamides, suggesting a potential risk for clinical antibiotic treatment efficacy. Moreover, KEGG pathway enrichment analysis revealed significant enrichment for fructose and mannose metabolism, streptomycin biosynthesis in the KO group. Furthermore, an increase in protective microbes alongside a decrease in potential pathogens in the KO microbiota hinted at altered immune responses due to USP25 deletion.

CONCLUSION: Our findings elucidate the essential role of USP25 in modulating gut microbiota composition and function, providing insights for future therapeutic strategies targeting gut microbiota in disease contexts.

CLINICAL TRAIL NUMBER: Not applicable.

RevDate: 2025-05-25
CmpDate: 2025-05-22

Terbtothakun P, Visedthorn S, Klomkliew P, et al (2025)

Clinical metagenomics analysis of bacterial and fungal microbiota from sputum of patients suspected with tuberculosis infection based on nanopore sequencing.

Scientific reports, 15(1):17772.

Tuberculosis (TB) remains a significant global health challenge, demanding rapid and comprehensive diagnostics for effective treatment. Secondary infections further complicate TB infection, worsening outcomes. Conventional diagnostics are hindered by prolonged turnaround times, high costs, and inability to detect co-infections. This study utilizes full-length 16S rDNA and internal transcribed spacer (ITS) amplicon sequencing based on Oxford Nanopore Technologies (ONT) to analyze clinical metagenomics of sputum microbiota from patients suspected with TB Infection. Our findings highlight the potential of ONT for profiling microbial communities associated with TB infection. The MTB group exhibited a significant abundance of Mycobacterium tuberculosis (M. tuberculosis) and Stenotrophomonas maltophilia. In contrast, Prevotella melaninogenica, Veillonella parvula, Corynebacterium striatum and Pseudomonas aeruginosa were more abundant in the negative samples. Fungal analysis revealed Candida orthopsilosis was enriched in MTB samples, while Aureobasidium leucospermi and Wallemia muriae predominated in negative samples. Correlation network analysis revealed M. tuberculosis exhibits positive and negative correlations with other microbial species, suggesting cooperative and competitive interactions that may influence microbial community dynamics and disease progression in TB patients. This study demonstrates the promise of ONT-based clinical metagenomics for rapid, comprehensive detection of bacterial and fungal co-infections, addressing limitations of conventional diagnostics and improving outcomes.

RevDate: 2025-05-25
CmpDate: 2025-05-22

Dillard LR, Glass EM, Kolling GL, et al (2025)

Genome-scale metabolic network reconstruction analysis identifies bacterial vaginosis-associated metabolic interactions.

Nature communications, 16(1):4768.

Bacterial vaginosis (BV) is the most prevalent vaginal condition among reproductive-age women presenting with vaginal complaints. Despite its significant impact on women's health, limited knowledge exists regarding the microbial community composition and metabolic interactions associated with BV. In this study, we analyze metagenomic data obtained from human vaginal swabs to generate in silico predictions of BV-associated bacterial metabolic interactions via genome-scale metabolic network reconstructions (GENREs). While most efforts to characterize symptomatic BV (and thus guide therapeutic intervention by identifying responders and non-responders to treatment) are based on genomic profiling, our in silico simulations reveal functional metabolic relatedness between species as quite distinct from genetic relatedness. We grow several of the most common co-occurring bacteria (Prevotella amnii, Prevotella buccalis, Hoylesella timonensis, Lactobacillus iners, Fannyhessea vaginae, and Aerrococcus christenssii) on the spent media of Gardnerella species and perform metabolomics to identify potential mechanisms of metabolic interaction. Through these analyses, we identify BV-associated bacteria that produce caffeate, a compound implicated in estrogen receptor binding, when grown in the spent media of other BV-associated bacteria. These findings underscore the complex and diverse nature of BV-associated bacterial community structures and several of these mechanisms are of potential significance in understanding host-microbiome relationships.

RevDate: 2025-05-22

Callens M, Le Berre G, Van den Bulcke L, et al (2025)

An Accessible Metagenomic Strategy Allows for Better Characterisation of Invertebrate Bulk Samples.

Molecular ecology resources [Epub ahead of print].

DNA-based techniques are a popular approach for assessing biodiversity in ecological research, especially for organisms which are difficult to detect or identify morphologically. Metabarcoding, the most established method for determining species composition and relative abundance in bulk samples, can be more sensitive and time- and cost-effective than traditional morphological approaches. However, one drawback of this method is PCR bias caused by between-species variation in the amplification efficiency of a marker gene. Metagenomics, bypassing PCR amplification, has been proposed as an alternative to overcome this bias. Several studies have already shown the promising potential of metagenomics, but they all indicate the unavailability of reference genomes for most species in any ecosystem as one of the primary bottlenecks preventing its wider implementation. In this study, we present a strategy that combines unassembled reads of low-coverage whole genome sequencing and publicly available reference genomes to construct a genomic reference database, thus circumventing high sequencing costs and intensive bioinformatic processing. We show that this approach is superior to metabarcoding for approximating relative biomass of macrobenthos species from bulk samples. Furthermore, these results can be obtained with a sequencing effort comparable to metabarcoding. The strategy presented here can thus accelerate the implementation of metagenomics in biodiversity assessments, as it should be relatively easy to adopt by laboratories familiar with metabarcoding and can be used as an accessible alternative.

RevDate: 2025-05-24
CmpDate: 2025-05-21

Jarmukhanov Z, Vinogradova E, Mukhanbetzhanov N, et al (2025)

Parity influences postpartum adaptations in the maternal gut microbiota.

Scientific reports, 15(1):17636.

The gut microbiome undergoes substantial modifications during pregnancy, yet its postpartum adaptations remain poorly understood, particularly with respect to the influence of parity. Here, we investigated the impact of childbirth history on maternal gut microbiome composition and function one month postpartum. By conducting metagenomic sequencing analysis on 60 participants (34 postpartum mothers and 26 controls), we demonstrated significant differences in microbial diversity and community structure between postpartum mothers and control, as well as subtle differences between first-time mothers and multiple-birth mothers. We identified parity-specific signatures, with first-time mothers showing enrichment in Dysosmobacter welbionis, Candidatus Saccharibacteria, and Anaerotruncus species. Functional analysis revealed distinct metabolic reprogramming patterns, including increased amino acid biosynthesis and modified fermentation pathways supporting postpartum recovery. We observed significant correlations between specific bacterial taxa and metabolic pathways, particularly in energy metabolism and immune modulation. Notably, the enhanced capacity for short-chain fatty acid production in primiparous mothers, mediated by Anaerotruncus and Dysosmobacter welbionis, suggests a potential role in shaping breast milk composition, which may influence neonatal development. These findings establish the concept of parity-dependent microbiome programming and provide insights into the biological mechanisms underlying maternal adaptation to pregnancy and childbirth.

RevDate: 2025-05-23
CmpDate: 2025-05-21

Abdillah A, Ravaux I, Mokhtari S, et al (2025)

Do Malassezia yeasts colonize the guts of people living with HIV?.

PloS one, 20(5):e0322982.

Malassezia yeasts are commensals of human skin. In contrast to culture-based studies, metagenomic studies have detected abundant Malassezia reads in the gut, especially in patients living with HIV. Whether Malassezia colonizes and persists in the gut remains an open question. This study aimed to describe the influence of HIV-associated immunodeficiency on gut colonization by Malassezia and to assess whether Malassezia are alive. Stool samples were prospectively collected over one-five visits from ten controls and 23 patients living with HIV (10 had CD4 < 200/mm3 and 13 had CD4 > 500/mm3). Each sample was cultured and subjected to Malassezia viability PCR and both fungal and bacterial metabarcoding. Abundant M. furfur colonies were cultured from an HIV-immunocompromised patient. M. furfur and M. globosa were isolated in very low quantities from healthy volunteers. Viability Malassezia-specific qPCR was positive in three HIV-immunocompromised patients. Metagenomic analyses showed that Malassezia reads were significantly more abundant in immunocompromised patients living with HIV and erratic over time in all participants. Our findings emphasise that Malassezia are rarely cultured from human stool samples, despite the use of specific culture media. Although HIV-related immunosuppression appears to be associated with the presence of Malassezia, these yeasts do not persist and colonise the gut, even in immunocompromised patients.

RevDate: 2025-05-21

Zhang T, Han Y, Peng Y, et al (2025)

The risk of pathogenicity and antibiotic resistance in deep-sea cold seep microorganisms.

mSystems [Epub ahead of print].

UNLABELLED: Deep-sea cold seeps host high microbial biomass and biodiversity that thrive on hydrocarbon and inorganic compound seepage, exhibiting diverse ecological functions and unique genetic resources. However, potential health risks from pathogenic or antibiotic-resistant microorganisms in these environments remain largely overlooked, especially during resource exploitation and laboratory research. Here, we analyzed 165 metagenomes and 33 metatranscriptomes from 16 global cold seep sites to investigate the diversity and distribution of virulence factors (VFs), antibiotic resistance genes (ARGs), and mobile genetic elements (MGEs). A total of 2,353 VFs are retrieved in 689 metagenome-assembled genomes (MAGs), primarily associated with indirect pathogenesis like adherence. In addition, cold seeps harbor nearly 100,000 ARGs, as important reservoirs, with high-risk ARGs (11.22%) presenting at low abundance. Compared to other environments, microorganisms in cold seeps exhibit substantial differences in VF and ARG counts, with potential horizontal gene transfer facilitating their spread. These virulome and resistome profiles provide valuable insights into the evolutionary and ecological implications of pathogenicity and antibiotic resistance in extreme deep-sea ecosystems. Collectively, these results indicate that cold seep sediments pose minimal public health risks, shedding light on environmental safety in deep-sea resource exploitation and research.

IMPORTANCE: In the "One Health" era, understanding pathogenicity and antibiotic resistance in vast and largely unexplored regions like deep-sea cold seeps is critical for assessing public health risks. These environments serve as critical reservoirs where resistant and virulent bacteria can persist, adapt, and undergo genetic evolution. The increasing scope of human activities, such as deep-sea mining, is disrupting these previously isolated ecosystems, heightening the potential for microbial exchange between deep-sea communities and human or animal populations. This interaction poses a significant risk for the dissemination of resistance and virulence genes, with potential consequences for global public health and ecosystem stability. This study offers the first comprehensive analysis of virulome, resistome, and mobilome profiles in cold seep microbial communities. While cold seeps act as reservoirs for diverse ARGs, high-risk ARGs are rare, and most VFs were low risk that contribute to ecological functions. These results provide a reference for monitoring the spread of pathogenicity and resistance in extreme ecosystems, informing environmental safety assessments during deep-sea resource exploitation.

RevDate: 2025-05-21

Xin T, Ye Q, D Hu (2025)

A relationship between body size and the gut microbiome suggests a conservation strategy.

Microbiology spectrum [Epub ahead of print].

A key goal of conservation is to protect the biodiversity of wild species to support their continued evolution and survival. Conservation practice has long been guided by genetic, ecological, and demographic indicators of risk. Cope's rule suggests that species tend to evolve larger body sizes over time. Here, we provide strong evidence to support the inclusion of body size when formulating wildlife conservation strategies. The gut microbiome can mirror the physiological and environmental adaptation status of the host. This study established a connection between body size and the gut microbiome in the Felidae family using 70 fecal samples collected from 18 individuals through metagenomic data analysis and mining metagenome-assembled genomes (MAGs). Two enterotypes were identified in the Felidae gut: Bacteroides and Clostridium. Medium-sized felids predominantly harbored Clostridium, associated with pathogenicity, whereas large and small felids harbored both beneficial Bacteroides and pathogenic Clostridium. Species that evolved larger body sizes over time exhibited distinct changes in gut microbial communities, such as enhanced nutrient extraction and metabolic capabilities. Larger felids exhibited a more diverse, stable gut microbiome engaged in metabolic processes and extensive host interactions, indicating an evolved functional role in various biological processes. Conversely, that of smaller felids is less diverse, with more viruses and pathogenic elements primarily involved in chemical synthesis. These findings provide essential insights for developing conservation strategies that consider the nutritional needs of different-sized feline species, control the transmission of pathogens, and allocate resources based on their unique gut microbiome characteristics.IMPORTANCEBody size is a fundamental trait that varies greatly among taxa and has important implications for life history and ecology. Cope's rule suggests that species tend to evolve larger body sizes over time. However, its correlation to body size evolution remains unclear. This study aimed to establish a connection between body size and the gut microbiome in the Felidae family through metagenomic data analysis. Our results support Cope's rule, illustrating that increased body size correlates with shifts in the gut microbiome, enhancing survival and adaptability.

RevDate: 2025-05-25
CmpDate: 2025-05-21

Zöggeler T, Kavallar AM, Pollio AR, et al (2025)

Meta-analysis of shotgun sequencing of gut microbiota in obese children with MASLD or MASH.

Gut microbes, 17(1):2508951.

Alterations in the gut microbiome affect the development and severity of metabolic dysfunction-associated steatotic liver disease (MASLD) or metabolic dysfunction-associated steatohepatitis (MASH). We analyzed microbiomes of obese children with and without MASLD, MASH, and healthy controls. Electronic databases were searched for studies on the gut microbiome in children with obesity with/without MASLD or MASH, providing shotgun-metagenomic-sequencing data. Nine studies and an additionally recruited cohort were included. Fecal microbiomes of children with MASLD (n = 153) and MASH (n = 70) were significantly different in alpha- and beta-diversity (p < 0.001) compared to obese (n = 58) and healthy (n = 132). Species Faecalibacterium_prausnitzii and Prevotella_copri are differentially abundant between obese, MASLD and MASH groups. XGBoost and random forest-models accurately predict MASLD over obesity with an AUROC of 87% and MASH over MASLD with 89%. Pathway-abundance-based models accurately predict MASLD over obesity with an AUROC of 81% and MASH over MASLD with 88%. The composition of the gut microbiome is altered with increasing hepatic fibrosis and concomitant species-abundance increase of Prevotella_copri (p = 0.0082). Machine-learning models discriminate pediatric from adult MASH with an AUROC of 97%. The gut microbial composition is increasingly altered in children with the progression of MASLD toward MASH. This can be utilized as a fecal biomarker and highlights the impact of diet on the gut microbiome for disease intervention.

RevDate: 2025-05-20
CmpDate: 2025-05-20

You Q, Wang K, Zhao Z, et al (2025)

Reduction of Bacteroides fragilis in Gut Microbiome of Chronic Hepatitis B Patients Promotes Liver Injury.

Journal of medical virology, 97(5):e70395.

In chronic hepatitis B (CHB) patients under antiviral treatment, liver injury, as evidenced by elevated alanine transaminase (ALT), is associated with unfavorable outcomes and needs effective treatment. The interaction between gut microbiota and liver injury in CHB patients remains unclear. Using a case-control design, 28 cases with elevated ALT and 28 matched controls with normal ALT were randomly selected from CHB patients with viral control. Clinical characteristics were comparable between groups. Metagenomic sequencing revealed that Bacteroides fragilis was decreased in cases and exhibited the greatest disparity between cases and controls. Mice colonized by gut microbiota from cases exhibited more severe liver damage in both LPS-induced and MCD diet-induced liver injury models, and had a lower abundance of B. fragilis compared to mice colonized by gut microbiota from controls. Oral gavage of B. fragilis improved both LPS-induced and MCD diet-induced liver injury. Metabolomics analysis revealed that the levels of 7-Ketolithocholic acid (7-Keto-LCA) were positively correlated with B. fragilis and significantly increased in the cultural supernatant of B. fragilis. Consistently, 7-Keto-LCA exerted protective effects against both LPS-induced and MCD diet-induced liver damage. Targeting gut microbiota might be a promising therapeutic treatment for alleviation residual liver inflammation in CHB patients with viral control.

RevDate: 2025-05-23
CmpDate: 2025-05-20

Yatera K, Wang Z, Shibata Y, et al (2025)

Sputum Microbiome, Potentially Pathogenic Organisms, and Clinical Outcomes in Japanese Patients with COPD and Moderate Airflow Limitation: The Prospective AERIS-J Study.

International journal of chronic obstructive pulmonary disease, 20:1477-1492.

BACKGROUND: In Western studies, lung microbiome changes are reported in patients with chronic obstructive pulmonary disease (COPD) and are associated with poorer outcomes, but similar studies in Asian patients or those with less severe COPD are limited.

METHODS: The Acute Exacerbation and Respiratory InfectionS in COPD Japan (AERIS-J; jRCT1080224632/NCT03957577) was a prospective, non-interventional study to evaluate sputum microbiome diversity at baseline and after 12 months (V2; exploratory analysis), in patients aged 40-80 years with stable COPD (June 2019-June 2022). Baseline sputum potentially pathogenic organisms (PPOs) were identified. Blood cell counts and COPD Assessment Test (CAT) scores were collected at baseline and COPD symptoms measured over 12 months using the Evaluating Respiratory Symptoms in COPD and EXAcerbations of Chronic pulmonary disease Tool, collected by eDiary.

RESULTS: Patients (N=63) had a mean age of 72.8 years, and percent predicted post-bronchodilator forced expiratory volume in 1 second was 58.3%; 92% were male. Across 62 baseline sputum samples, microbiome composition was similar between 16S rRNA/metagenomic datasets. Patients graded Global Initiative for Chronic Obstructive Lung Disease (GOLD) III versus GOLD I/II had minimal differences in their microbial taxonomic profile and no differences in microbial diversity (Wilcoxon P=0.71). Alpha diversity (Shannon index) positively correlated with blood basophils (rho=0.41; P=0.0019) and negatively correlated with CAT score (rho=0.36; P=0.0069). Alpha diversity and sputum (rho: -0.0637; P=0.7836) or blood (rho: 0.1739; P=0.2043) eosinophils were not correlated. No difference in alpha (P=0.5) or beta (P=0.3) diversity or Operational Taxonomic Unit (Anosim R=-0.024; P=0.892) was observed between PPO-positive or -negative sputum.

CONCLUSION: A less diverse microbiome correlated with poorer health status and lower blood basophils in patients with COPD and moderate airflow limitation. There was no relationship between PPO presence and microbiome diversity.

RevDate: 2025-05-28
CmpDate: 2025-05-28

El-Son MAM, Elbahnaswy S, Khormi MA, et al (2025)

Harnessing the fish gut microbiome and immune system to enhance disease resistance in aquaculture.

Fish & shellfish immunology, 163:110394.

The increasing global reliance on aquaculture is challenged by disease outbreaks, exacerbated by antibiotic resistance, and environmental stressors. Traditional strategies, such as antibiotic treatments and chemical interventions, are becoming less effective, necessitating a shift toward microbiota-based disease control. The fish gut microbiome is a key determinant of immune homeostasis and pathogen resistance. However, previous reviews lack integration of microbiome engineering, machine learning, and next-generation sequencing in fish health strategies. This review encompasses recent advancements in microbiome research, including dietary strategies such as prebiotics, probiotics, synbiotics, and phytogenic feed additives. It synthesizes the latest metagenomic insights, microbiota modulation techniques, and AI-driven disease prediction models. It presents a novel conceptual framework for disease control using microbiome-based approaches in aquaculture. Additionally, we explore emerging methodologies, including microbiota transplantation and synthetic probiotics, to develop precision microbiome interventions. By bridging existing knowledge gaps, this review provides actionable insights into sustainable aquaculture practices through microbiome-driven disease resistance.

RevDate: 2025-05-28
CmpDate: 2025-05-28

Tanaka M, Toyonaga T, Nakagawa F, et al (2025)

Dietary 3-aminobenzoic acid enhances intestinal barrier integrity and attenuates experimental colitis.

American journal of physiology. Gastrointestinal and liver physiology, 328(6):G801-G810.

Disruption of intestinal epithelial integrity and increased permeability is central to the pathogenesis of ulcerative colitis (UC). In this study, we identified 3-aminobenzoic acid (3-ABA), a dietary component abundant in azuki beans, soybeans, and chickpeas as a regulator of epithelial permeability and inflammation in the colon. Screening 119 gut microbial metabolites revealed the ability of 4-ABA, a structural isomer of 3-ABA, to enhance barrier function in Caco2 cells. Further analysis of structural isomers identified 3-ABA as the most effective, significantly increasing transepithelial electrical resistance and reducing epithelial permeability. Using liquid chromatography-mass spectrometry, 3-ABA was detected in dietary beans and human fecal samples. Fecal 3-ABA levels were significantly lower in patients with UC compared with healthy individuals. Metagenomic and functional prediction analyses revealed dysbiosis in patients with UC, characterized by an enrichment of bacterial genes involved in ABA degradation. Gene expression analysis of 3-ABA-stimulated Caco2 cells demonstrated upregulation of tight junction molecules, such as CLDN1 and TJP1, enhancing epithelial barrier integrity. In a dextran sodium sulfate-induced colitis mouse model, rectal 3-ABA administration ameliorated colitis by enhancing epithelial barrier function and reducing inflammation. These findings highlight 3-ABA's potential as a dietary therapeutic agent for UC, offering a novel strategy to enhance intestinal integrity and mitigate inflammation.NEW & NOTEWORTHY Increased intestinal epithelial permeability is central to the pathogenesis of ulcerative colitis (UC). 3-Aminobenzoic acid (3-ABA), a dietary component abundant in beans, decreased epithelial permeability and attenuated colonic inflammation in a mouse experimental colitis model. Reduced fecal 3-ABA levels in patients with UC were associated with dysbiosis-driven accelerated degradation. These findings highlight the therapeutic potential of 3-ABA in UC by targeting colonic epithelium.

RevDate: 2025-05-20
CmpDate: 2025-05-20

Ren Z, Wang M, Yu J, et al (2025)

Unearthing Vertical Stratified Archaeal Community and Associated Methane Metabolism in Thermokarst Sediments.

Environmental microbiology, 27(5):e70110.

Thermokarst lakes are hotspots for greenhouse gas emissions across the Arctic and Qinghai-Tibet Plateau. Investigating the vertical stratification of archaeal communities in thermokarst lake sediments is essential for understanding their ecological roles and contributions to methane production. Here, we analysed archaeal communities along a depth gradient in thermokarst lake sediments. Alpha diversity (richness and Shannon index) generally decreased with depth. Euryarchaeota was the most abundant phylum, though its relative abundance declined with depth, while Thaumarchaeota increased. At the order level, Methanosarcinales and Nitrosopumilales showed increased relative abundance with depth, indicating adaptation to deeper anoxic layers, whereas Methanomicrobiales and Methanotrichales decreased. Beta diversity increased with depth, shifting from stochastic to deterministic processes. Network topology revealed reduced species connectivity but heightened modularity at depth, signalling niche specialisation. Functionally, genes associated with the initial steps of methane metabolism (Fwd, Mtd, Mer) increased with depth, while those involved in later steps (Mtr, Mcr) decreased, suggesting reduced energy conservation efficiency and lower overall methanogenesis rates in deeper sediments. These findings highlight the significant impact of vertical stratification on archaeal community structure, interaction networks, and functional capabilities.

RevDate: 2025-05-21
CmpDate: 2025-05-20

Liao H, Wen C, Huang D, et al (2025)

Harnessing phage consortia to mitigate the soil antibiotic resistome by targeting keystone taxa Streptomyces.

Microbiome, 13(1):127.

BACKGROUND: Antimicrobial resistance poses a substantial and growing threat to global health. While antibiotic resistance genes (ARGs) are tracked most closely in clinical settings, their spread remains poorly understood in non-clinical environments. Mitigating the spread of ARGs in non-clinical contexts such as soil could limit their enrichment in food webs.

RESULTS: Multi-omics (involving metagenomics, metatranscriptomics, viromics, and metabolomics) and direct experimentation show that targeting keystone bacterial taxa by phages can limit ARG maintenance and dissemination in natural soil environments. Based on the metagenomic analysis, we first show that phages from activated sludge can regulate soil microbiome composition and function in terms of reducing ARG abundances and changing the bacterial community composition. This effect was mainly driven by a reduction in the abundance and activity of Streptomyces genus, which is well known for encoding both antibiotic resistance and synthesis genes. To validate the significance of this keystone species for the loss of ARGs, we enriched phage consortia specific to Streptomyces and tested their effect on ARG abundances on 48 soil samples collected across China. We observed a consistent reduction in ARG abundances across all soils, confirming that Streptomyces-enriched phages could predictably change the soil microbiome resistome and mitigate the prevalence of ARGs. This study highlights that phages can be used as ecosystem engineers to control the spread of antibiotic resistance in the environment.

CONCLUSION: Our study demonstrates that some bacterial keystone taxa are critical for ARG maintenance and dissemination in soil microbiomes, and opens new ecological avenues for microbiome modification and resistome control. This study advances our understanding of how metagenomics-informed phage consortia can be used to predictably regulate soil microbiome composition and functioning by targeting keystone bacterial taxa. Video Abstract.

RevDate: 2025-05-21
CmpDate: 2025-05-20

Teng T, Huang F, Xu M, et al (2025)

Microbiota alterations leading to amino acid deficiency contribute to depression in children and adolescents.

Microbiome, 13(1):128.

BACKGROUND: Major depressive disorder (MDD) in children and adolescents is a growing global public health concern. Metabolic alterations in the microbiota-gut-brain (MGB) axis have been implicated in MDD pathophysiology, but their specific role in pediatric populations remains unclear.

RESULTS: We conducted a multi-omics study on 256 MDD patients and 307 healthy controls in children and adolescents, integrating plasma metabolomics, fecal metagenomics, and resting-state functional magnetic resonance imaging (rs-fMRI) of the brain. KEGG enrichment analysis of 360 differential expressed metabolites (DEMs) indicated significant plasma amino acid (AA) metabolism deficiencies (p-value < 0.0001). We identified 58 MDD-enriched and 46 MDD-depleted strains, as well as 6 altered modules in amino acid metabolism in fecal metagenomics. Procrustes analysis revealed the association between the altered gut microbiome and circulating AA metabolism (p-value = 0.001, M[2] = 0.932). Causal analyses suggested that plasma AAs might mediate the impact of altered gut microbiota on depressive and anxious symptoms. Additionally, rs-fMRI revealed that connectivity deficits in the frontal lobe are associated with depression and 22 DEMs in AA metabolism. Furthermore, transplantation of fecal microbiota from MDD patients to adolescent rats induced depressive-like behaviors and 14 amino acids deficiency in the prefrontal cortex (PFC). Moreover, the dietary lysine restriction increased depression susceptibility in adolescent rats by reducing the expression of excitatory amino acid transporters in the PFC.

CONCLUSIONS: Our findings highlight that gut microbiota alterations contribute to AAs deficiency, particularly lysine, which plays a crucial role in MDD pathogenesis in children and adolescents. Targeting AA metabolism may offer novel therapeutic strategies for pediatric depression. Video Abstract.

RevDate: 2025-05-22
CmpDate: 2025-05-19

Yang M, Qi Y, Gao P, et al (2025)

Changes in the assembly and functional adaptation of endophytic microbial communities in Amorphophallus species with different levels of resistance to necrotrophic bacterial pathogen stress.

Communications biology, 8(1):766.

Pcc is one of the key pathogenic factors responsible for destructive soft rot in konjac. To date, the assembly and functional adaptation of the plant endophytic microbiome under Pcc stress remain poorly understood. Here, we found that Pcc stress leads to rapid reorganization of the endogenous microbiome in multiple organs of both susceptible and resistant konjac plants. Under Pcc stress, the negative interactions within the bacterial-fungal interdomain network intensified, suggesting an increase in ecological competition between bacterial and fungal taxa. We further discovered that the relative abundance dynamics of the classes Dothideomycetes and Sordariomycetes, as core fungal taxa, changed in response to Pcc stress. By isolating culturable microorganisms, we demonstrated that 46 fungal strains strongly inhibited the growth of Pcc. This implies that endophytic fungal taxa in konjac may protect the host plant through ecological competition or by inhibiting the growth of pathogenic bacteria. Metagenomic analysis demonstrated that microbial communities associated with resistant Amorphophallus muelleri exhibited unique advantages over susceptible Amorphophallus konjac in enhancing environmental adaptability, regulating plant immune signaling, strengthening cell walls, and inducing defense responses. Our work provides important evidence that endophytic fungal taxa play a key role in the host plant's defense against necrotizing bacterial pathogens.

RevDate: 2025-05-27
CmpDate: 2025-05-27

Majernik SN, Beaver L, PH Bradley (2025)

Small amounts of misassembly can have disproportionate effects on pangenome-based metagenomic analyses.

mSphere, 10(5):e0085724.

Individual genes from microbiomes can drive host-level phenotypes. To help identify such candidate genes, several recent tools estimate microbial gene copy numbers directly from metagenomes. These tools rely on alignments to pangenomes, which, in turn, are derived from the set of all individual genomes from one species. While large-scale metagenomic assembly efforts have made pangenome estimates more complete, mixed communities can also introduce contamination into assemblies, and it is unknown how robust pangenome-based metagenomic analyses are to these errors. To gain insight into this problem, we re-analyzed a case-control study of the gut microbiome in cirrhosis, focusing on commensal Clostridia previously implicated in this disease. We tested for differentially prevalent genes in the Lachnospiraceae and then investigated which were likely to be contaminants using sequence similarity searches. Out of 86 differentially prevalent genes, we found that 33 (38%) were probably contaminants originating in taxa such as Veillonella and Haemophilus, unrelated genera that were independently correlated with disease status. Our results demonstrate that even small amounts of contamination in metagenome assemblies, below typical quality thresholds, can threaten to overwhelm gene-level metagenomic analyses. However, we also show that such contaminants can be accurately identified using a method based on gene-to-species correlation. After removing these contaminants, we observe that several flagellar motility gene clusters in the Lachnospira eligens pangenome are associated with cirrhosis status. We have integrated our analyses into an analysis and visualization pipeline, PanSweep, that can automatically identify cases where pangenome contamination may bias the results of gene-resolved analyses.IMPORTANCEMetagenome-assembled genomes, or MAGs, can be constructed without pure cultures of microbes. Large-scale efforts to build MAGs have yielded more complete pangenomes (i.e., sets of all genes found in one species). Pangenomes allow us to measure strain variation in gene content, which can strongly affect phenotype. However, because MAGs come from mixed communities, they can contaminate pangenomes with unrelated DNA; how much this impacts downstream analyses has not been studied. Using a metagenomic study of gut microbes in cirrhosis as our test case, we investigate how contamination affects analyses of microbial gene content. Surprisingly, even small, typical amounts of MAG contamination (<5%) result in disproportionately high levels of false positive associations (38%). Fortunately, we show that most contaminants can be automatically flagged and provide a simple method for doing so. Furthermore, applying this method reveals a new association between cirrhosis and gut microbial motility.

RevDate: 2025-05-27
CmpDate: 2025-05-27

Doing G, Shanbhag P, Bell I, et al (2025)

TEAL-Seq: targeted expression analysis sequencing.

mSphere, 10(5):e0098424.

Metagenome sequencing enables the genetic characterization of complex microbial communities. However, determining the activity of isolates within a community presents several challenges, including the wide range of organismal and gene expression abundances, the presence of host RNA, and low microbial biomass at many sites. To address these limitations, we developed "targeted expression analysis sequencing" or TEAL-seq, enabling sensitive species-specific analyses of gene expression using highly multiplexed custom probe pools. For proof of concept, we targeted about 1,700 core and accessory genes of Staphylococcus aureus and S. epidermidis, two key species of the skin microbiome. Two targeting methods were applied to laboratory cultures and human nasal swab specimens. Both methods showed a high degree of specificity, with >90% reads on target, even in the presence of complex microbial or human background DNA/RNA. Targeting using molecular inversion probes demonstrated excellent correlation in inferred expression levels with bulk RNA-seq. Furthermore, we show that a linear pre-amplification step to increase the number of nucleic acids for analysis yielded consistent and predictable results when applied to complex samples and enabled profiling of expression from as little as 1 ng of total RNA. TEAL-seq is much less expensive than bulk metatranscriptomic profiling, enables detection across a greater dynamic range, and uses a strategy that is readily configurable for determining the transcriptional status of organisms in any microbial community.IMPORTANCEThe gene expression patterns of bacteria in microbial communities reflect their activity and interactions with other community members. Measuring gene expression in complex microbiome contexts is challenging, however, due to the large dynamic range of microbial abundances and transcript levels. Here we describe an approach to assessing gene expression for specific species of interest using highly multiplexed pools of targeting probes. We show that an isothermal amplification step enables the profiling of low biomass samples. TEAL-seq should be widely adaptable to the study of microbial activity in natural environments.

RevDate: 2025-05-27
CmpDate: 2025-05-27

Yuan J, Yang J, Sun Y, et al (2025)

An early microbial landscape: inspiring endeavor from the China Space Station Habitation Area Microbiome Program (CHAMP).

Science China. Life sciences, 68(6):1541-1554.

China's progressing space program, as evidenced by the formal operation of the China Space Station (CSS), has provided great opportunities for various space missions. Since microbes can present potential risks to human health and the normal operation of spacecraft, the study on space-microorganisms in the CSS is always a matter of urgency. In addition, the knowledge on the interactions between microorganisms, astronauts, and spacecraft equipment will shed light on our understanding of life activities in space and a closed environment. Here, we present the first comprehensive report on the microbial communities aboard the CSS based on the results of the first two survey missions of the CSS Habitation Area Microbiome Program (CHAMP). By combining metagenomic and cultivation methods, we have discovered that, in the early stage of the CSS, microbial communities are dominated by human-associated microbes, with strikingly large differences in both composition and functional diversity compared to those found on the International Space Station (ISS). While the samples from two missions of CHAMP possessed substantial differences in microbial composition, no significant difference in functional diversity was found, although signs of accumulating antibiotic resistance were evident. Meanwhile, strong bacteria co-occurrence was noted within the station's microbiota. At the strain level, environmental isolates from the CSS exhibited numerous genomic mutations compared to those from the Assembly, Integration, and Test (AIT) center, potentially linked to the adaptation to the unique conditions of space. Besides, the intraspecies variation within four high-abundance species suggests possible propagation and residency effects between sampling sites. In summary, this study offers critical insights that not only advance our understanding of space microbiology but also lay the groundwork for effective microbial management in future long-term human space missions.

RevDate: 2025-05-22
CmpDate: 2025-05-19

Salehi M, Laitinen V, Bhanushali S, et al (2025)

Gender differences in global antimicrobial resistance.

NPJ biofilms and microbiomes, 11(1):79.

Antimicrobial resistance is one of the leading causes of mortality globally. However, little is known about the distribution of antibiotic resistance genes (ARGs) in human gut metagenomes, collectively referred to as the resistome, across socio-demographic gradients. In particular, limited evidence exists on gender-based differences. We investigated how the resistomes differ between women and men in a global dataset of 14,641 publicly available human gut metagenomes encompassing countries with widely variable economic statuses. We observed a 9% higher total ARG load in women than in men in high-income countries. However, in low- and middle-income countries, the difference between genders was reversed in univariate models, but not significant after adjusting for covariates. Interestingly, the differences in ARG load between genders emerged in adulthood, suggesting resistomes differentiate between genders after childhood. Collectively, our data-driven analyses shed light on global, gendered antibiotic resistance patterns, which may help guide further research and targeted interventions.

RevDate: 2025-05-22
CmpDate: 2025-05-19

Kohnert E, C Kreutz (2025)

Benchmarking Differential Abundance Tests for 16S microbiome sequencing data using simulated data based on experimental templates.

PloS one, 20(5):e0321452.

Differential abundance (DA) analysis of metagenomic microbiome data is essential for understanding microbial community dynamics across various environments and hosts. Identifying microorganisms that differ significantly in abundance between conditions (e.g., health vs. disease) is crucial for insights into environmental adaptations, disease development, and host health. However, the statistical interpretation of microbiome data is challenged by inherent sparsity and compositional nature, necessitating tailored DA methods. This benchmarking study aims to simulate synthetic 16S microbiome data using metaSPARSim (Patuzzi I, Baruzzo G, Losasso C, Ricci A, Di Camillo B. MetaSPARSim: a 16S rRNA gene sequencing count data simulator. BMC Bioinformatics. 2019;20:416. https://doi.org/10.1186/s12859-019-2882-6 PMID: 31757204) MIDASim (He M, Zhao N, Satten GA. MIDASim: a fast and simple simulator for realistic microbiome data. Available from: https://doi.org/10.1101/2023.03.23.533996), and sparseDOSSA2 (Ma S, Ren B, Mallick H, Moon YS, Schwager E, Maharjan S, et al. A statistical model for describing and simulating microbial community profiles. PLOS Comput Biol. 2021;17(9):e1008913. https://doi.org/10.1371/journal.pcbi.1008913 PMID: 34516542) , leveraging 38 real-world experimental templates (S3 Table) previously utilized in a benchmark study comparing DA tools. These datasets, drawn from diverse environments such as human gut, soil, and marine habitats, serve as the foundation for our simulation efforts. We employ the same 14 DA tests that were previously used with the same experimental data in benchmark studies alongside 8 DA tests that were developed subsequently. Initially, we will generate synthetic data closely mirroring the experimental datasets, incorporating a known truth to cover a broad range of real-world data characteristics. This approach allows us to assess the ability of DA methods to recover known true differential abundances. We will further simulate datasets by altering sparsity, effect size, and sample size, thus creating a comprehensive collection for applying the 22 DA tests. The outcomes, focusing on sensitivities and specificities, will provide insights into the performance of DA tests and their dependencies on sparsity, effect size, and sample size. Additionally, we will calculate data characteristics (S1 and S2 Table) for each simulated dataset and use a multiple regression to identify informative data characteristics influencing test performance. Our prior study, where we used simulated data without incorporating a known truth, demonstrated the feasibility of using synthetic data to validate experimental findings. This current study aims to enhance our understanding by systematically evaluating the impact of known truth incorporation on DA test performance, thereby providing further information for the selection and application of DA methods in microbiome research.

RevDate: 2025-05-21
CmpDate: 2025-05-19

Wang S, Kong F, Dai D, et al (2025)

Deterministic succession patterns in the rumen and fecal microbiome associate with host metabolic shifts in peripartum dairy cattle.

GigaScience, 14:.

BACKGROUND: Metabolic disorders in peripartum ruminants affect health and productivity, with gut microbiota playing a key role in host metabolism. Therefore, our study aimed to characterize the gut microbiota of peripartum dairy cows to better understand the relationship between metabolic phenotypes and the rumen and fecal microbiomes during the peripartum period.

RESULTS: In a longitudinal study of 91 peripartum cows, we analyzed rumen and fecal microbiomes via 16S rRNA and metagenomic sequencing across six time points. By using enterotype classification, ecological model, and random forest analysis, we identified distinct deterministic succession patterns in the rumen and fecal microbiomes (rumen: rapid transition-transition-stable; hindgut: stable-transition-stable). Key microbes, such as Succiniclasticum and Bifidobacterium, were found to drive microbial succession by balancing stochastic and deterministic processes. Notably, we observed that changes in gut microbiota succession patterns significantly influenced metabolic phenotypes (e.g., serum non-esterified fatty acid, glucose, and insulin levels). Mediation analysis suggested that specific gut microbes (e.g., Prevotella sp900315525 in the rumen and Alistipes sp015059845 in the hindgut) and metabolic pathways (e.g., glucose-related pathway) were associated with host metabolic phenotypes.

CONCLUSIONS: Overall, utilizing a large gut microbiome dataset and enterotype- and ecological model-based microbiome analyses, we comprehensively elucidated the succession and assembly of the gut microbiota in peripartum dairy cows. We further confirmed that changes in gut microbiota succession patterns were significantly related to the metabolic phenotypes of peripartum dairy cows. These findings provide valuable insights for developing health management strategies for peripartum ruminants.

RevDate: 2025-05-26
CmpDate: 2025-05-26

Liu H, Gan Y, He B, et al (2025)

mNGS technique was used to analyze the microbiome structure of intervertebral disc tissue in 99 patients with degenerative disc disease.

European spine journal : official publication of the European Spine Society, the European Spinal Deformity Society, and the European Section of the Cervical Spine Research Society, 34(5):1709-1721.

OBJECTIVE: Whether bacterial hypotoxic infection in the intervertebral disc is the cause of disc degenerative disease (DDD) is controversial. The mNGS technique can provide valuable insights by obtaining more comprehensive evidence of the presence of bacteria in the intervertebral disc. This study was designed to analyze the characteristics of intervertebral microbiome structure in patients with lumbar disc degenerative disease and its correlation with clinical indicators.

METHODS: A total of 104 patients with lumbar disc degenerative diseases were included in this study. The surgically removed lumbar intervertebral disc tissues were collected for clinical culture and metagenomic second-generation sequencing (mNGS), and the consistency of the two microbial detection methods was compared.According to the collected clinical information, patients were grouped according to the modified Pfirrmann grading, Modic typing and age, and the differences of microbial communities detected by mNGS among different groups were compared, including α diversity analysis, β diversity analysis, species abundance difference analysis, etc. Spearman correlation between clinical features and generic relative abundance was calculated.

RESULTS: The effective culture results of 104 intervertebral disc tissue samples were only 19 cases positive, with a positive rate of 18.3% (19/104), and the mNGS detection results were positive in 99 cases, with a positive rate of 95.2% (99/104). According to the 19 samples with positive culture, nearly half 47.4% (9/19) of staphylococcus species were positive, and all the positive species were basically epidermal common colonization species or environmental common bacteria. At the same time, we conducted two times of mNGS sequencing for these 19 samples, and the consistency rate between the two sequencing results and the culture results was 84.2% (16/19). According to the results of mNGS detection, 250 species from 110 genera were detected in 99 positive samples. The results of group analysis showed that patients with lower degree of disc degeneration (modified Pfirrmann ≤ 4) and young patients (age < 45 years) had more abundant microbial communities in disc tissue (P < 0.05). Correlation analysis showed that there was a positive correlation between Arcobacter skirrowii and improved Pfirrmann classification at the species level (P < 0.01). There was a negative correlation between pseudomonas thermotolerans and modified Pfirrmann classification (P < 0.05). There was a positive correlation between Staphylococcus hominis and Modic typing scores (P < 0.05). Staphylococcus arlettae was negatively correlated with age (P < 0.05). At the genus level, Arcobacter had a significant positive correlation with the modified Pfirrmann grade and Modic classification (P < 0.05), Corynebacterium had a significant negative correlation with the modified Pfirrmann grade (P < 0.05), and Pseudomonas had a significant negative correlation with age (P < 0.05). After our follow-up of six months to one year, two of the patients included in this study eventually developed severe lumbar disc infection, and the rest did not develop infection.

CONCLUSIONS: This study proves that hypotoxic infection may be involved in the degeneration of intervertebral disc, and the bacterial species that cause this occult infection may be more abundant than previously thought. In addition, there was a significant correlation between the biome structure of these bacteria and clinical indicators. The hypothesis of the cause of this insidious infection has the potential to change the way the disease is treated.

RevDate: 2025-05-26
CmpDate: 2025-05-26

Torshizi Esfahani A, Zafarjafarzadeh N, Vakili F, et al (2025)

Gut microbiome in colorectal cancer: metagenomics from bench to bedside.

JNCI cancer spectrum, 9(3):.

Colorectal cancer (CRC) is a major global health challenge. Emerging research highlights the pivotal role of the gut microbiota in influencing CRC risk, progression, and treatment response. Metagenomic approaches, especially high-throughput shotgun sequencing, have provided unprecedented insights into the intricate connections between the gut microbiome and CRC. By enabling comprehensive taxonomic and functional profiling, metagenomics has revealed microbial signatures, activities, and biomarkers associated with colorectal tumorigenesis. Furthermore, metagenomics has shown a potential to guide patient stratification, predict treatment outcomes, and inform microbiome-targeted interventions. Despite remaining challenges in multi-omics data integration, taxonomic gaps, and validation across diverse cohorts, metagenomics has propelled our comprehension of the intricate gut microbiome-CRC interplay. This review underscores the clinical relevance of microbial signatures as potential diagnostic and prognostic tools in CRC. Furthermore, it discusses personalized treatment strategies guided by this omics' approach.

RevDate: 2025-05-26
CmpDate: 2025-05-26

Liu X, Luo Y, Chen X, et al (2025)

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

Allergy, 80(5):1377-1388.

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: 2025-05-21
CmpDate: 2025-05-19

Bonacolta AM, Krause-Massaguer J, Unuma T, et al (2025)

The Sea Cucumber-Infecting Parasite Apostichocystis gudetama gen. nov. sp. nov. Expands Marine-Host-Specific Clade of Apicomplexans.

The Journal of eukaryotic microbiology, 72(3):e70013.

Unknown ellipsoid bodies, later classified as apicomplexan cysts, are prevalent in the ovaries of Japanese sea cucumbers (Apostichopus japonicus), where they can lead to lower fecundity in infected individuals and adverse effects on wild populations as well as aquaculture efforts for this endangered species. Apicomplexans are widespread and essential to marine environments, where they can affect the health and fitness of host populations. We performed genomic sequencing of recovered cysts to gain more ecological and evolutionary information on this parasite. We recovered this apicomplexan's complete nuclear ribosomal RNA (rrn) operon, the entire mitochondrial genome, and a partial apicoplast (relic chloroplast) genome. The rrn operon phylogeny revealed this parasite as being closely related to coccidian-like parasites of marine fish (ichthyocolids) and cnidarians (corallicolids), while organelle phylogenomics hint at a closer relation to the protococcidian Eleutheroschizon. Using this new phylogenetic context and previous morphological descriptions, we describe this parasite as Apostichocystis gudetama gen. nov. sp. nov. Mining available microbiomes reveal the presence of Apostichocystis spp. beyond its host range, alluding to other potential hosts or cryptic, closely related lineages. Its phylogenetic placement has important implications concerning the evolution of parasitism within Apicomplexa and the divergence of a marine-host-specific clade of coccidian-like parasites.

RevDate: 2025-05-20
CmpDate: 2025-05-17

Yang Q, Downey R, Stark JS, et al (2025)

The Microbial Ecology of Antarctic Sponges.

Microbial ecology, 88(1):44.

Microbial communities in Antarctic marine sponges have distinct taxonomic and functional profiles due to low temperatures, seasonal days and nights, and geographic isolation. These sponge holobionts contribute to nutrient cycling, structural habitat formation, and benthic ecosystem resilience. We review Antarctic sponge holobiont knowledge, integrating culture-based and molecular data across environmental and taxonomic gradients. Although microbiome data exist for only a fraction of the region's 593 known sponge species, these hosts support diverse symbionts spanning at least 63 bacterial, 5 archaeal, and 6 fungal phyla, highlighting the complexity and ecological significance of these understudied polar microbiomes. A conserved core microbiome, dominated by Proteobacteria, Bacteroidetes, Nitrospinae, and Planctomycetes, occurs across Antarctic sponges, alongside taxa shaped by host identity, depth, and environment. Metagenomic data indicate microbial nitrogen cycling, chemoautotrophic carbon fixation, and stress tolerance. Despite these advances, major knowledge gaps remain, particularly in deep-sea and sub-Antarctic regions, along with challenges in taxonomy, methodological biases, and limited functional insights. We identify key research priorities, including developing standardised methodologies, expanded sampling across ecological and depth gradients, and integrating multi-omics with environmental and host metadata. Antarctic sponge holobionts provide a tractable model for investigating microbial symbiosis, functional adaptation, and ecosystem processes in one of Earth's most rapidly changing marine environments.

RevDate: 2025-05-20
CmpDate: 2025-05-17

Schilling M, Jagdev M, Thomas H, et al (2025)

Metagenomic analysis of mosquitoes from Kangerlussuaq, Greenland reveals a unique virome.

Scientific reports, 15(1):17141.

Climate change is dramatically affecting vector ecology in extreme environments such as the Arctic. However, little is known about the current status of viruses of arthropod vectors located in such northerly locations. As part of a field survey on the role of wildlife in international movement of zoonotic pathogens, we sampled mammalophilic mosquitoes near the settlement of Kangerlussuaq, Greenland in July 2022 and July 2023 to investigate their virome. The majority of mosquitoes were identified as either Aedes impiger or Aedes nigripes. Metagenomic analysis of RNA extracted from species pools detected a number of novel RNA viruses belonging to a range of different virus families, including Flaviviridae, Orthomyxoviridae, Bunyavirales, Totiviridae and Rhabdoviridae. However, the sequence identities when compared to previously published, were as low as 34% at the amino acid level. Furthermore, a comparison of virome diversity between Aedes species emphasises the uniqueness of both Aedes impiger and Aedes nigripes from this secluded ecosystem. It also highlights the need to better understand the viromes of potential pathogen vectors as the impacts of climate change are experienced in such northerly ecosystems.

RevDate: 2025-05-17
CmpDate: 2025-05-17

Zhang Z, Ran X, Guo Z, et al (2025)

Microbial diversity, functional properties, and flavor characteristics of high-temperature Daqu with different colors.

Food research international (Ottawa, Ont.), 212:116406.

High-temperature Daqu (HTD) plays a crucial role in the quality of sauce-flavor baijiu. Daqu of different colors serves distinct functions in the baijiu brewing process. However, indicators for distinguishing among different-colored Daqu remain insufficient. This study investigated the microbial community structures, physicochemical properties, and E-sensory characteristics of different-colored HTD from Shandong Province. The results revealed significant differences in microbial communities among the three HTD types (P < 0.05). Kroppenstedtia eburnea, three Bacillus species, and Weizmannia coagulans were significantly enriched in white Daqu; an unclassified Staphylococcus species dominated in black Daqu; and Aspergillus oryzae, Aspergillus fumigatus, and Proteus mirabilis were highly abundant in yellow Daqu. Compared to HTD from Guizhou and Hubei, Shandong HTD was characterized by microbial species such as Proteus mirabilis and Bacillus velezensis. Using metagenomic analysis, we, for the first time, identified Thermomyces lanuginosus, Lentibacillus daqui, and an unclassified Thermoascus species as potential major contributors to pyrazine synthesis in HTD. The primary differences among the three colored Shandong Daqu types lay in their aroma profiles rather than taste. Electronic nose and electronic tongue analyses demonstrated that the W6S and W3S sensors effectively distinguished black and white Daqu, respectively, marking a novel application of these technologies in Daqu analysis. Acidity was identified as a key factor influencing microbial community structure, flavor characteristics, and enzyme activities, with a nonlinear relationship observed between acidity and enzyme activities. This study highlights the microbial and sensory distinctions among different-colored HTD and provides effective indicators for distinguishing these three types of Daqu.

RevDate: 2025-05-19
CmpDate: 2025-05-17

Zhang S, Zheng N, Zhao S, et al (2025)

Allicin enhances urea-N conversion to microbial-N by inhibiting urease activity and modulating the rumen microbiome in cattle.

Microbiome, 13(1):124.

BACKGROUND: Urea serves as a vital nonprotein nitrogen source in ruminant nutrition, but its efficient utilization is often hampered due to rapid urease activity in the rumen. This study explores the potential of allicin, a garlic-derived compound, as a urease inhibitor to improve urea nitrogen utilization. Enzyme inhibition kinetics and molecular docking were used to identify allicin's interaction sites on urease. Additionally, metagenomic and [15]N-urea metabolic flux analyses were conducted to evaluate allicin's impact on microbial populations and urea-N metabolism.

RESULTS: Allicin was identified as an inhibitor of ruminal urease, with an IC50 of 126.77 ± 1.21 μM. Molecular docking studies have shown that allicin forms hydrogen bonds with key urease residues, leading to the preemption of the urease active site and thus impeding urea binding. In a simulated rumen environment, allicin significantly reduced urea hydrolysis and ammonia production. Furthermore, allicin modified the rumen microbial community by inhibiting Prevotella species while promoting the growth of Ruminobacter species and Denitrobacterium detoxificans. A [15]N-urea metabolic flux analysis revealed that allicin facilitated the incorporation of urea-derived nitrogen into microbial amino acids and nucleotides.

CONCLUSION: Allicin effectively inhibits urease activity in the rumen, enhancing the conversion of urea-N into microbial biomass. These findings suggest that allicin has significant potential to optimize urea metabolism in the rumen, offering a novel strategy for improving ruminant nitrogen nutrition. Video Abstract.

RevDate: 2025-05-16
CmpDate: 2025-05-16

Sarhan MS, Antonello G, Weissensteiner H, et al (2025)

Human mitochondrial DNA in public metagenomes: Opportunity or privacy threat?.

Cell, 188(10):2561-2566.

Human DNA is unavoidably present in metagenomic analyses of human microbiomes. While current protocols remove human DNA before submission to public repositories, mitochondrial DNA (mtDNA) has been overlooked and frequently persists. We discuss the privacy risks and research opportunities associated with mtDNA, urging consideration by the scientific, ethics, and legal communities.

RevDate: 2025-05-19
CmpDate: 2025-05-16

Veseli I, Chen YT, Schechter MS, et al (2025)

Microbes with higher metabolic independence are enriched in human gut microbiomes under stress.

eLife, 12:.

A wide variety of human diseases are associated with loss of microbial diversity in the human gut, inspiring a great interest in the diagnostic or therapeutic potential of the microbiota. However, the ecological forces that drive diversity reduction in disease states remain unclear, rendering it difficult to ascertain the role of the microbiota in disease emergence or severity. One hypothesis to explain this phenomenon is that microbial diversity is diminished as disease states select for microbial populations that are more fit to survive environmental stress caused by inflammation or other host factors. Here, we tested this hypothesis on a large scale, by developing a software framework to quantify the enrichment of microbial metabolisms in complex metagenomes as a function of microbial diversity. We applied this framework to over 400 gut metagenomes from individuals who are healthy or diagnosed with inflammatory bowel disease (IBD). We found that high metabolic independence (HMI) is a distinguishing characteristic of microbial communities associated with individuals diagnosed with IBD. A classifier we trained using the normalized copy numbers of 33 HMI-associated metabolic modules not only distinguished states of health vs IBD, but also tracked the recovery of the gut microbiome following antibiotic treatment, suggesting that HMI is a hallmark of microbial communities in stressed gut environments.

RevDate: 2025-05-24
CmpDate: 2025-05-24

Ahmad W, Coffman L, Ray R, et al (2025)

Flooding episodes and seed treatment influence the microbiome diversity and function in the soybean root and rhizosphere.

The Science of the total environment, 982:179554.

Climate change-related events such as flooding have threatened crop productivity, agricultural sustainability, and global food security by causing hypoxic conditions. Such conditions impaire root development and nutrient acquisition, and alter root rhizospheric microbial communities that are vital for plant health and productivity. Seed treatment with pathogen protection have been key to maintaining early seed germination and plant productivity in field conditions. Still, their role in flooding stress and microbiome diversity and functionality in soybeans is poorly understood. Here, we performed field-based investigations to understand the impact of flooding episodes (0, 3, and 7 days after floodings; DAF) and seed treatment (Cruiser MAXX) on soybean plant growth and rhizosphere microbiome diversity and functionality. Flooding episodes significantly reduced seed yield (746 kg ha[-1]) compared to untreated control. However, the seed treatment increased plant height and pods per plant (3-DAF) and reduced flood injury by 33 % (7-DAF). The shotgun metagenomic analysis showed that seed treatment significantly enhanced the microbial community in rhizospheric soil. Flooding episodes impacted the microbial communities with higher abundance at 3-DAF than at 7-DAF. Flooding stress reduced the microbial diversity, although Proteobacteria increased as root endophytes. Seed treatment and flooding combinations decreased microbiome functionality and reduced gene counts for phytohormone biosynthesis, fermentation, nitrogen, symbiosis, and degradation pathways. Similarly, flooding stress shifted the carbohydrate synthesis to a more specialized substrate. These findings enhance understanding of soybean root and rhizosphere microbiome diversity and functionality dynamics during flooding stress and provide a platform to develop sustainable agricultural practices for enhancing soybean stress tolerance to flooding.

RevDate: 2025-05-25
CmpDate: 2025-05-25

Zhi N, Chang X, Zha L, et al (2025)

Platycodonis radix polysaccharides suppress progression of high-fat-induced obesity through modulation of intestinal microbiota and metabolites.

Phytomedicine : international journal of phytotherapy and phytopharmacology, 142:156653.

BACKGROUND: Obesity is a prevalent chronic condition worldwide, posing a significant risk to public health. Polysaccharides derived from Platycodonis Radix (PR) have been identified as the primary bioactive compounds in combating obesity, although the underlying molecular mechanisms remain inadequately understood.

PURPOSE: The purpose of the research is to analyze the potential anti-obesity influnces within PR polysaccharides (PG: PG1 and PG2) by analyzing their impact on gut microbiota (GM) composition, SCFA and BA metabolism, and the regulation of associated gene and protein expression.

STUDY DESIGN AND METHODS: In this research, 7-week-old male C57BL/6 mice were assigned to a HFD or a control chow diet for 90 days to evaluate the therapeutic effects of PG intervention. Metagenomic analysis was performed to assess GM alterations, while GC-MS and LC-MS were used to quantify SCFA and BA concentrations in cecal contents, respectively. Furthermore, the effects of PG on SCFA- and BA-associated metabolic pathways were examined through qRT-PCR and WB.

RESULTS: PG1 demonstrated superior efficacy compared to PG2 in reducing HFD-induced obesity and associated metabolic disturbances. High-dose PG1 treatment effectively inhibited weight gain, dyslipidemia, inflammation, liver damage, and fat deposition caused by the HFD. Additionally, PG1 treatment primarily promoted the abundance of SCFA-producing bacteria, enhanced the expression of GPR41 and GPR43 genes, significantly elevated levels of GLP-1 and PYY, and improved circulating leptin and adiponectin levels. The intervention with PG1 notably enhanced the relative abundances of bacteria involved in the production of secondary BAs, such as Lachnospiraceae_NK4A136 and Eubacterium coprostanoligenes. This augmentation facilitated the transformation of primary BAs into secondary forms, diminished the relative expression of intestinal FXR and FGF15, and reduced FGFR4 levels. Consequently, this led to an upregulation of hepatic CYP7A1, accelerating liver cholesterol metabolism and the synthesis of new BAs.

CONCLUSION: Supplementation with PG1 protects mice from obesity induced by an HFD. The observed protective effects of PG1 appear to be primarily mediated through the activation of the GM-SCFA-GPR pathway and the inhibition of the GM-BA-FXR-FGF15 signaling pathway.

RevDate: 2025-05-25
CmpDate: 2025-05-25

Hong Y, Cui J, Xu G, et al (2025)

Intestinal IL-17 family orchestrates microbiota-driven histone deacetylation and promotes Treg differentiation to mediate the alleviation of asthma by Ma-Xing-Shi-Gan decoction.

Phytomedicine : international journal of phytotherapy and phytopharmacology, 142:156656.

BACKGROUND: Gut microbiota imbalance is well-known as one important trigger of allergic asthma. Ma-Xing-Shi-Gan decoction (MXSG) is a traditional Chinese medicine prescription with ideal clinical efficacy on asthma. However, whether and how MXSG exerts its efficacy on asthma through gut microbiota remains unclear.

PURPOSE: To investigate the underlying mechanism of MXSG against asthma using multi-omics technologies.

METHODS: An asthma model was established using 8-week-old C57BL/6 J mice, after which they were daily administrated with high-, medium- and low-dose MXSG for 7 days. Histopathological examinations and flow cytometry were performed to evaluate the effects of MXSG on lung immune injury. Key regulatory pathways were predicted via network pharmacology and verified using 16S rRNA sequencing, metagenomics, metabolomics, and in vivo experiments including the knockout of the targeting gene.

RESULTS: MXSG alleviated asthma symptoms, elevated intestinal microbial diversities, and enriched potential beneficial microbes such as Lactococcus, Lactobacillus, and Limosilactobacillus. Network pharmacology and experimental validation highlighted the IL-17/Treg signaling as crucial for asthma treatment. IL-17 knockout experiments revealed its necessity for Treg differentiation during asthma. Moreover, IL-17-deficient asthmatic mice exhibited lower levels of Lactobacillus and significant changes in microbial genes involving histone deacetylases (HDAC) and short-chain fatty acids (SCFAs). Finally, MXSG significantly boosted SCFA production and reduced HDAC9 expression, which were correlated with Treg cell ratios.

CONCLUSION: Our study delineates a novel mechanism where MXSG synergizes with the IL-17 family to enrich intestinal beneficial microbes (e.g. Lactobacillus) and SCFAs. This inhibits the expression of SCFA-downstream HDAC9 to promote Treg differentiation, and thus potentially alleviates asthma.

RevDate: 2025-05-22
CmpDate: 2025-05-22

Orsi AS, Lemos Junior WJF, Alegbeleye OO, et al (2025)

Sodium chloride reduction in meat processing: Microbial shifts, spoilage risks, and metagenomic insights.

Meat science, 226:109848.

This review evaluated the impact of sodium chloride (NaCl) reduction or substitution on the microbial ecology of meat products, with a focus on how these changes affect shelf life and safety. Reducing NaCl in fresh meat products promotes the growth of psychrotrophic spoilage bacteria, such as Pseudomonas sp., which thrive at low temperatures, and mesophilic pathogens like Escherichia coli and Staphylococcus aureus, particularly under inadequate storage conditions. In cured and fermented meats, such as salami, lowering NaCl levels disrupts the balance of salt-tolerant microorganisms, notably lactic acid bacteria (LAB) and coagulase-negative staphylococci, potentially leading to increased spoilage and pathogen proliferation. In smoked meats, the combination of reduced NaCl and altered microbial ecology, including a shift toward LAB dominance, may weaken the inhibitory effects on spore-forming bacteria like Clostridium botulinum. Additionally, using metagenomics, we explore the shifts in microbial communities observed in studies involving meat, revealing critical insights into the composition and diversity of bacteria in meat products, as well as the gaps in research on the impact of NaCl reduction and/or substitution on the microbiota. This review provides a comprehensive understanding of these microbial shifts, highlighting the distinct responses of psychrotrophic, mesophilic, and LAB groups to NaCl modification and the need to understand the effects of these alternatives on the meat product microbiome, as well as the neglected microorganisms that can affect the quality and safety of these products.

RevDate: 2025-05-24
CmpDate: 2025-05-24

Li X, He N, Wang H, et al (2025)

Therapeutic effect of Faecalibacterium longum CM04-06 on DSS-induced ulcerative colitis in mice.

Journal of applied microbiology, 136(5):.

AIMS: This study explores the impact of Faecalibacterium longum CM04-06 on inflammatory bowel disease (IBD) by regulating gut microbiota in mice.

METHODS AND RESULTS: We reanalyzed the distribution of the CM04-06 genome in the metagenome of the IBD cohort and observed a significantly higher abundance of CM04-06 in healthy individuals compared to patients with UC or CD. The prophylactic administration of CM04-06 was evaluated for its effects on intestinal microbial diversity and community composition after a two-week trial in mice. The intestinal microbiota was characterized using metagenomic sequencing of fecal samples on the DNBSEQ platform. CM04-06 treatment resulted in a significant reduction in the Disease Activity Index (DAI) and histological scores, as well as a decrease in the levels of pro-inflammatory cytokines, including IL-1β, IL-6, and TNF-α, in both the colon and serum of DSS-induced mice. Furthermore, supplementation with CM04-06 significantly reduced the levels of pro-inflammatory cytokines in both the colon and serum. Additionally, CM04-06 enhanced the integrity of the intestinal epithelial barrier by increasing the expression of tight junction proteins and mucin. Moreover, we observed greater abundances of Faecalibaculum rodentium, Alistipes onderdonkii, Alistipes shahii, and Bifidobacterium animalis after CM04-06 treatment.

CONCLUSIONS: CM04-06 prevents and alleviates intestinal inflammation by modulating the composition of the microbiota community, increasing the abundance of beneficial probiotics, and suppressing pro-inflammatory cytokine levels.

RevDate: 2025-05-21
CmpDate: 2025-05-15

Jansen D, Deleu S, Caenepeel C, et al (2025)

Virome drift in ulcerative colitis patients: faecal microbiota transplantation results in minimal phage engraftment dominated by microviruses.

Gut microbes, 17(1):2499575.

Ulcerative colitis (UC) is an inflammatory bowel disease characterized by recurrent colonic inflammation. Standard treatments focus on controlling inflammation but remain ineffective for one-third of patients. This underscores the need for alternative approaches, such as fecal microbiota transplantation (FMT), which transfers healthy donor microbiota to patients. The role of viruses in this process, however, remains underexplored. To address this, we analyzed the gut virome using metagenomic sequencing of enriched viral particles from 320 longitudinal fecal samples of 44 patients enrolled in the RESTORE-UC FMT trial. Patients were treated with FMTs from healthy donors (allogenic, treatment) or themselves (autologous, control). We found that colonic inflammation, both its presence and location, had a greater impact on the gut virome than FMT itself. In autologous FMT patients, the virome was unstable and showed rapid divergence over time, a phenomenon we termed virome drift. In allogenic FMT patients, the virome temporarily shifted toward the healthy donor, lasting up to 5 weeks and primarily driven by microviruses. Notably, two distinct virome configurations were identified and linked to either healthy donors or patients. In conclusion, inflammation strongly affects the gut virome in UC patients, which may lead to instability and obstruct the engraftment of allogeneic FMT.

RevDate: 2025-05-16
CmpDate: 2025-05-15

Zhang Y, Liu H, H Jing (2025)

Community differences and potential function along the particle size spectrum of microbes in the twilight zone.

Microbiome, 13(1):121.

BACKGROUND: The twilight zone, which extends from the base of the euphotic zone to a depth of 1000 m, is the major area of particulate organic carbon (POC) remineralization in the ocean. However, little is known about the microbial community and metabolic activity that are directly associated with POC remineralization in this consistently underexplored realm. Here, we utilized a large-volume in situ water transfer system to collect the microbes on different-sized particles from the twilight zone in three regions and analyzed their composition and metabolic function by metagenomic analysis.

RESULTS: Distinct prokaryotic communities with significantly lower diversity and less endemic species were detected on particles in the South East Asian Time-series Study (SEATS) compared with the other two regions, perhaps due to the in situ physicochemical conditions and low labile nutrient availability in this region. Observable transitions in community composition and function at the upper and lower boundaries of the twilight zone suggest that microbes respond differently to (and potentially drive the transformation of) POC through this zone. Substantial variations among different particle sizes were observed, with smaller particles typically exhibiting lower diversity but harboring a greater abundance of carbon degradation-associated genes than the larger particles. Such a pattern might arise due to the relatively larger surface area of the smaller particles relative to their volume, which likely provides more sites for microbial colonization, increasing their chance of being remineralized. This makes them less likely to be transferred to the deep ocean, and thus, they contribute more to carbon recycling than to long-term sequestration. Both contig-based and metagenome-assembled genome-(MAG-) based analyses revealed a high diversity of the Carbohydrate-Active enZymes (CAZy) family. This indicates the versatile carbohydrate metabolisms of the microbial communities associated with sinking particles that modulate the remineralization and export of POC in the twilight zone.

CONCLUSION: Our study reveals significant shifts in microbial community composition and function in the twilight zone, with clear differences among the three particle sizes. Microbes with diverse metabolic potential exhibited different responses to the POC entering the twilight zone and also collectively drove the transformation of POC through this zone. These findings provided insights into the diversity of prokaryotes in sinking particles and their roles in POC remineralization and export in marine ecosystems. Video Abstract.

RevDate: 2025-05-17
CmpDate: 2025-05-15

Song XL, Wang ZJ, Yin XW, et al (2025)

The impact of nitrogen deposition on nitrogen metabolism in ryegrass lawn with different soil nutrient levels.

Scientific reports, 15(1):16755.

Nitrogen deposition is a crucial factor in global change, which is widespread across various regions globally. It has drawn extensive attention due to its direct modification of soil nitrogen retention and nitrogen species distribution, thereby influencing nitrogen metabolism across entire ecosystems. Previous studies on its influence on nitrogen metabolism have not reached a consensus. In an urban ryegrass lawn mesocosm experiment, we set two levels of nitrogen deposition and soil nutrients respectively, aiming to study the impacts of these factors on the N-cycling process through metagenomic analysis. The results demonstrated nitrogen deposition increased nitrification, nitrogen fixation, denitrification, and dissimilatory nitrate reduction, but decreased assimilatory nitrate reduction in the nitrogen metabolism process by changing soil nitrogen availability and the abundance of N-cycling functional genes in the soil microbial community. The soil nutrient levels exhibited effects opposite to those of nitrogen deposition, negatively impacting nitrification, denitrification, and nitrogen fixation in the nitrogen metabolism process. This work further elucidates the impacts of nitrogen deposition on the ecological functions of the ryegrass lawn with different soil nutrient levels, and predicts the potential impacts of intensified nitrogen deposition on these ecological functions. It provides valuable theoretical support for understanding and evaluating complex ecological interactions.

RevDate: 2025-05-17
CmpDate: 2025-05-15

Serivichyaswat PT, Scholte T, Wilms T, et al (2025)

Metagenomic biodiversity assessment within an offshore wind farm.

Scientific reports, 15(1):16786.

Environmental DNA (eDNA) analysis can be a powerful tool for monitoring biodiversity and assessing human impacts on ecosystems. In this study, we employed a genome-wide metagenomic eDNA approach to assess the marine biodiversity within and around the Horns Rev 1 offshore wind farm in the Danish North Sea. Seawater samples were collected from both within the windfarm and surrounding control sites, sequenced, and analyzed using a combination of DNA k-mer matching and alignment-based classification methods. We identified a wide range of species across the tree of life-highlighting the species richness of this marine ecosystem. Our results revealed a high degree of species diversity congruence between the wind farm and control sites. While this could suggest minimal ecological disruption of the wind farm, we cannot rule out that the influence of ocean currents and water mixing the DNA from different regions dominate the species detection. We detected bioindicator species, such as Thalassiosira, Phaeocystis and Skeletonema, which can provide insights into water quality. Our metagenomic approach also enabled us to obtain population genomics insights for species, such as the European anchovy (Engraulis encrasicolus) and the diatom Rhizosolenia setigera, and genetically confirmed the origin of the invasive Sea walnut (Mnemiopsis leidyi) in the North Sea. This study highlights the potential of genome-wide eDNA metagenomics as a framework for assessing marine biodiversity and detecting population-level genetic signals, contributing to informed and scalable ecosystem monitoring strategies.

RevDate: 2025-05-14

Antonaru LA, Rad-Menéndez C, Mbedi S, et al (2025)

Evolution of far-red light photoacclimation in cyanobacteria.

Current biology : CB pii:S0960-9822(25)00502-0 [Epub ahead of print].

Cyanobacteria oxygenated the atmosphere of early Earth and continue to be key players in global carbon and nitrogen cycles. A phylogenetically diverse subset of extant cyanobacteria can perform photosynthesis with far-red light through a process called far-red light photoacclimation, or FaRLiP. This phenotype is enabled by a cluster of ∼20 genes and involves the synthesis of red-shifted chlorophylls d and f, together with paralogs of the ubiquitous photosynthetic machinery used in visible light. The FaRLiP gene cluster is present in diverse, environmentally important cyanobacterial groups, but its origin, evolutionary history, and connection to early biotic environments have remained unclear. This study takes advantage of the recent increase in (meta)genomic data to help clarify this issue: sequence data mining, metagenomic assembly, and phylogenetic tree networks were used to recover more than 600 new FaRLiP gene sequences, corresponding to 51 new gene clusters. These data enable high-resolution phylogenetics and-by relying on multiple gene trees, together with gene arrangement conservation-support FaRLiP appearing early in cyanobacterial evolution. Sampling information shows that considerable FaRLiP diversity can be observed in microbialites to the present day, and we hypothesize that the process was associated with the formation of microbial mats and stromatolites in the early Paleoproterozoic. The ancestral FaRLiP cluster was reconstructed, revealing features that have been maintained for billions of years. Overall, far-red-light-driven oxygenic photosynthesis may have played a significant role in Earth's early history.

RevDate: 2025-05-23
CmpDate: 2025-05-23

Zhang L, Wang S, Jia Y, et al (2025)

Alterations in microbial communities and antibiotic resistance genes pre- and post-sludge bulking in a wastewater treatment plant.

Environmental pollution (Barking, Essex : 1987), 376:126391.

Sludge bulking is a common issue in wastewater treatment plants (WWTPs) that can disrupt microbial communities and potentially impact the abundance and spread of antibiotic resistance genes (ARGs) within treatment systems. This study employed high-throughput 16S rRNA gene sequencing and metagenomic sequencing to examine the changes in microbial communities and ARGs in a WWTP during non-bulking and bulking periods. The results indicated that bacterial diversity decreased in bulking sludge while maintaining a high removal efficiency of conventional pollutants. Significant differences were detected at the bacterial genus level between non-bulking and bulking sludge (p < 0.05). The proliferation of Candidatus_Microthrix contributed to sludge bulking, while Micropruina improved sludge settleability. When treating wastewater with the same water quality and quantity, anaerobic/anoxic/oxic (A[2]/O) exhibited the highest resistance to sludge bulking, followed by Bardenpho and the Carrousel oxidation ditch. The abundance of ARGs in bulking sludge (28.15-43.63 ppm) was lower than that in non-bulking sludge (51.72-59.01 ppm). The ARGs removal efficiency reached 96.24 % and 94.34 % during bulking and non-bulking periods, respectively. Network analysis revealed that Candidatus_Microthrix was positively correlated with aadS and tetX, and norank_f_Saprospiraceae exhibited positive correlations with vanRO and ANT(3″)-Iia. These findings provide valuable insights into the impacts of sludge bulking on WWTP performance and ARGs dynamics, informing evidence-based policies for sustainable wastewater treatment.

RevDate: 2025-05-23
CmpDate: 2025-05-23

Fu CM, Luo SQ, Tang DR, et al (2025)

Effect of bacteriocin RSQ01 on milk microbiota during pasteurized milk preservation.

Journal of dairy science, 108(6):5705-5718.

Milk has high risk for microbial contamination. RSQ01, a bacteriocin, previously has shown potentiality for pasteurized milk preservation. This study analyzed the effects of RSQ01 on milk microbiota by comparison of bacterial number and composition in 3 pasteurized milk groups: controls without RSQ01, treatment group with the addition of 2× MIC (low concentration), and treatment group with the addition of 4× MIC RSQ01 (high concentration). Integrated 16S ribosomal DNA sequencing and metagenomics of these groups after 3 d of storage showed inhibition of RSQ01 on microbiota diversity. Pathogenic bacteria such as Salmonella showed a decrease in relative abundance after RSQ01 treatment, whereas probiotic bacteria such as Lactococcus showed an increase, indicating that RSQ01 contributed to milk preservation by maintaining a low abundance of pathogens and a relatively high abundance of probiotics. Further investigations revealed that milk preservation was primarily attributed to the ability of RSQ01 to decrease the relative abundance of genes related to metabolism of energy and nutrients (e.g., vitamins, lipids, and AA) of microbiota, with change of genetic, environmental, and cellular processes. Interestingly, RSQ01 generally reduced the relative abundance of virulence factors and quorum-sensing-related genes in microbiota, likely reducing virulence and resistance. The findings provided insights into microbiomics mechanisms regarding pasteurized milk preservation of bacteriocins.

RevDate: 2025-05-23
CmpDate: 2025-05-23

Guajardo-Leiva S, Díez B, Rojas-Fuentes C, et al (2025)

From sewage to genomes: Expanding our understanding of the urban and semi-urban wastewater RNA virome.

Environmental research, 276:121509.

Wastewater is a hotspot for viral diversity, harboring various microbial, plant, and animal viruses, including those that infect humans. However, the dynamics, resilience, and ecological roles of viral communities during treatment are largely unknown. In this study, we explored RNA virus ecogenomics using metagenomics from influent and effluent samples across three wastewater catchment areas in Chile, with a population of 7.05 million equivalent inhabitants. We identified 14,212 RNA-dependent RNA polymerase (RdRP)-coding sequences from the Orthornavirae kingdom, clustering into 4989 viral species. Using extensive databases of 14,150 family-level representative sequences, we classified 90 % of our sequences at the family level. Our analysis revealed that treatment reduced viral richness and evenness (Shannon index), but phylogenetic diversity remained unchanged. Effluents showed lower richness and evenness than influents with similar phylogenetic diversity. Species turnover, influenced by catchment area and treatment, accounted for 54 % of sample dissimilarities (Weighted Unifrac). Biomarker analysis indicated that families like Astroviridae and Fiersviridae were more abundant in influents, while Reoviridae and Virgaviridae dominated effluents. This suggests that viral resistance to treatment varies and cannot be solely attributed to genome type, size, or morphology. We traced viral genomes through time and space, identifying sequences like the Pepper Mild Mottle Virus (PMMoV) from the Virgaviridae family over large distances and periods, highlighting its wastewater marker potential. High concentrations of human pathogens, such as Rotavirus (Reoviridae) and Human Astrovirus (Astroviridae), were found in both influents and effluents, stressing the need for continuous monitoring, especially for treated wastewater reuse.

RevDate: 2025-05-23
CmpDate: 2025-05-23

Liu M, Wang S, Zhou H, et al (2025)

Thermal environment driving specific microbial species to form the visible biofilms on the UNESCO World Heritage Dazu Rock Carvings.

Environmental research, 276:121510.

The Dazu Rock Carvings, a UNESCO World Heritage site with over a millennium of history, are facing significant deterioration from microbial biofilms. However, the key microbial species responsible and the environmental factors driving their growth remain unclear. To address this gap, we conducted metagenomic sequencing to characterize the microbial community on the carvings, followed by correlation analyses with a variety of environmental factors in the surrounding air and within the rocks. Bacterial communities exhibited significantly higher richness and diversity than eukaryotic communities, though diversity metrics showed no significant differences between visibly colonized and uncolonized surfaces. We identified a distinctive consortium of 64 bacterial species, 35 fungal species, and 1 algal species specifically associated with visible biofilms, occurring at 9.56-fold higher relative abundance in colonized areas. These microorganisms contribute to characteristic green, brown-black, and white coloration on the carvings. Statistical analysis revealed absolute humidity and dew point temperature as key environmental factors influencing biofilm visibility, with thresholds of 21.00 g/m[3] and 23.4 °C respectively, above which biofilms became visible. This study provides precise targets for conservation efforts and establishes critical environmental parameters to guide preservation strategies for this irreplaceable cultural heritage.

RevDate: 2025-05-17
CmpDate: 2025-05-15

Wang L, Chen X, Pollock NR, et al (2025)

Metagenomic analysis reveals distinct patterns of gut microbiota features with diversified functions in C. difficile infection (CDI), asymptomatic carriage and non-CDI diarrhea.

Gut microbes, 17(1):2505269.

Clostridioides difficile infection (CDI) has been recognized as a leading cause of healthcare-associated infections and a considerable threat to public health globally. Increasing evidence suggests that the gut microbiota plays a key role in the pathogenesis of CDI. The taxonomic composition and functional capacity of the gut microbiota associated with CDI have not been studied systematically. Here, we performed a comprehensive shotgun metagenomic sequencing in a well-characterized human cohort to reveal distinct patterns of gut microbiota and potential functional features associated with CDI. Fecal samples were collected from 104 inpatients, including : (1) patients with clinically significant diarrhea and positive nucleic acid amplification testing (NAAT) and received CDI treatment (CDI, n = 47); (2) patients with positive stool NAAT but without diarrhea (Carrier, n = 17); (3) patients with negative stool NAAT but with diarrhea (Diarrhea, n = 14); and (4) patients with negative stool NAAT and without diarrhea (Control, n = 26). Downstream statistical analyses (including alpha and beta diversity analysis, differential abundance analysis, correlation network analysis, and potential functional analysis) were then performed. The gut microbiota in the Control group showed higher Chao1 index (p < 0.05), while Shannon index at KEGG module level was higher in CDI than in Carrier and Control (p < 0.05). Beta diversity for species composition differed significantly between CDI vs Carrier/Control cohorts (p < 0.05). Microbial Linear discriminant analysis Effect Size and ANCOM analysis both identified 8 species (unclassified_f_Enterobacteriaceae, Veillonella_parvula, unclassified_g_Klebsiella and etc.) were enriched in CDI, Enterobacter_aerogenes was enriched in Diarrhea, Collinsella_aerofaciens, Collinsella_sp_4_8_47FAA, Collinsella_tanakaei and Collinsella_sp_CAG_166 were enriched in Control (LDA >3.0, adjusted p < 0.05). Correlation network complexity was higher in CDI with more negative correlations than in other three cohorts. Modules involved in iron complex transport system (M00240) was enriched in CDI, ABC-2 type transport system (M00254), aminoacyl-tRNA biosynthesis (M00359), histidine biosynthesis (M00026) and inosine monophosphate biosynthesis (M00048) were enriched in Carrier, ribosome (M00178 and M00179) was enriched in Diarrhea, fluoroquinolone resistance (M00729) and aminoacyl-tRNA biosynthesis (M00360) were enriched in Control (LDA > 2.5, adjusted p < 0.05). Resistance functions of acriflavine and glycylcycline were enriched in CDI, while resistance function of bacitracin was enriched in Carrier (LDA > 3.0, adjusted p < 0.05), and the contributions of phylum and species to resistance functions differed among the four groups. Our results reveal alterations of gut microbiota composition and potential functions among four groups of differential colonization/infection status of Clostridioides difficile. These findings support the potential roles of gut microbiota and their potential functions in the pathogenesis of CDI.

RevDate: 2025-05-14

Li J, Zheng K, Ding W, et al (2025)

Healthy and moribund Zhikong scallops (Chlamys farreri) developed different viral communities during a mass mortality event.

mSystems [Epub ahead of print].

UNLABELLED: Viral assemblages of scallops are still relatively unknown. Here, metagenomic analysis was used to study virus communities in the gut of scallops to establish the first scallop virome data set (SVD); this contains 7,447 viral operational taxonomic units. Protein-sharing networks and phylogenetic analyses demonstrated the high diversity and novelty of the SVD, which is very different from viromes from other habitats. Potentially pathogenic viruses are prevalent in the gut of scallops. In particular, the novel smacoviruses were identified, indicating that scallops may be a potential hotspot for this viral group. Inference of virus-host associations found extensive interactions between viruses and major prokaryotic lineages. Intriguingly, moribund scallops showed a higher diversity of auxiliary metabolic genes (AMGs) related to amino acid metabolism and cofactor and vitamin genes, while healthy scallops had fewer AMGs, with those present focusing on secondary metabolite biosynthesis and carbohydrate metabolism. These findings provide the first landscape of scallop gut viruses based on metagenomes and highlight the potential roles of diverse and unique gut viruses for the health of filter-feeding bivalves.

IMPORTANCE: This study uses metagenome sequencing to establish the first scallop virome database. The study reveals previously unknown diversity of scallop-associated viruses and provides insights into links between disease status and viral diversity and genome content. The study will interest many aquatic virologists and could have important implications in managing marine resources.

RevDate: 2025-05-15

Liu L, Wang Z, Luo C, et al (2025)

Beneficial soil microbiome profiles assembled using tetramycin to alleviate root rot disease in Panax notoginseng.

Frontiers in microbiology, 16:1571684.

BACKGROUND: Root rot disease is a major threat to the sustainable production of Panax notoginseng. Tetramycin has a broad-spectrum fungicidal efficacy, low toxicity, and high efficiency, However, the prevention and control of root rot disease of P. notoginseng and the specific mechanism of action are still unclear.

METHODS: In this paper, a combination of indoor and pot experiments was used to assess the effectiveness of tetramycin at alleviating root rot disease challenges encountered by P. notoginseng. Amplicon sequencing, metagenomic analysis with microbial verification were used to investigate the microecological mechanisms underlying tetramycin's ability to reduce soil biological barriers.

RESULTS: We found that tetramycin significantly inhibited mycelial growth and spore germination of pathogenic fungi. Tetramycin, T2 (1000×) and T3 (500×), applied to continuous cropping soil, increased the seedling survival rates of P. notoginseng. Additionally, tetramycin reduced fungal α-diversity and shifted the fungal community assembly from deterministic to stochastic process. The microbial functions influenced by tetramycin were primarily associated with antibiotic synthesis and siderophore synthesis. Antibiotic efflux and inactivation have also been identified as the main resistance mechanisms. Microbial verification results showed that the artificially assembled tetramycin-regulated microbial community could indeed alleviate the occurrence of diseases. Furthermore, the cross-kingdom synthetic community assembled by the three key strains (Pseudomonas aeruginosa, Variovorax boronicumulans, and Cladosporium cycadicola) significantly improved the control of root rot disease and promoted plant growth.

DISCUSSION: This study provides novel insights into developing efficient biological control strategies and elucidates the role and mechanism of tetramycin in modulating soil microflora assembly to strengthen host disease resistance.

RevDate: 2025-05-17
CmpDate: 2025-05-14

Zhou L, Li J, Ding C, et al (2025)

Mechanistic Advances in Hypoglycemic Effects of Natural Polysaccharides: Multi-Target Regulation of Glycometabolism and Gut Microbiota Crosstalk.

Molecules (Basel, Switzerland), 30(9):.

Natural polysaccharides (NPs), as a class of bioactive macromolecules with multitarget synergistic regulatory potential, exhibit significant advantages in diabetes intervention. This review systematically summarizes the core hypoglycemic mechanisms of NPs, covering structure-activity relationships, integration of the gut microbiota-metabolism-immunity axis, and regulation of key signaling pathways. Studies demonstrate that the molecular weight, branch complexity, and chemical modifications of NPs mediate their hypoglycemic activity by influencing bioavailability and target specificity. NPs improve glucose metabolism through multiple pathways: activating insulin signaling, improving insulin resistance (IR), enhancing glycogen synthesis, inhibiting gluconeogenesis, and regulating gut microbiota homeostasis. Additionally, NPs protect pancreatic β-cell function via the nuclear factor E2-related factor 2 (Nrf2)/Antioxidant Response Element (ARE) antioxidant pathway and Toll-like receptor 4 (TLR4)/nuclear factor-κB (NF-κB) anti-inflammatory pathway. Clinical application of NPs still requires overcoming challenges such as resolving complex structure-activity relationships and dynamically integrating cross-organ signaling. Future research should focus on integrating multi-omics technologies (e.g., metagenomics, metabolomics) and organoid models to decipher the cross-organ synergistic action networks of NPs, and promote their translation from basic research to clinical applications.

RevDate: 2025-05-16
CmpDate: 2025-05-14

Žukienė G, Narutytė R, V Rudaitis (2025)

Association Between Vaginal Microbiota and Cervical Dysplasia Due to Persistent Human Papillomavirus Infection: A Systematic Review of Evidence from Shotgun Metagenomic Sequencing Studies.

International journal of molecular sciences, 26(9):.

The role of vaginal dysbiosis in the progression of human papilloma virus (HPV) associated cervical lesions has gained attention in recent years. While many studies use 16S rRNA gene sequencing for microbiota analysis, shotgun metagenomic sequencing offers higher taxonomic resolution and insights into microbial gene functions and pathways. This systematic review evaluates the relationship between compositional and functional changes in the vaginal microbiome during HPV infection and cervical lesion progression. A literature search was performed according to PRISMA guidelines in PubMed, Web of Science, Scopus, and ScienceDirect databases. Seven studies utilizing metagenomic sequencing in patients with HPV infection or HPV-associated cervical lesions were included. Progression from HPV infection to cervical lesions and cancer was associated with a reduction in Lactobacillus species (particularly Lactobacillus crispatus) and an enrichment of anaerobic and pathogenic species, especially Gardnerella vaginalis. Heterogeneous enriched metabolic pathways were also identified, indicating functional shifts during lesion progression. As most studies were conducted in Asia, further research in diverse regions is needed to improve the generalizability of findings. Future studies employing metagenomic sequencing may help identify biomarkers for early pre-cancerous lesions and clarify the role of vaginal microbiota in persistent HPV infection and cervical dysplasia.

RevDate: 2025-05-16
CmpDate: 2025-05-14

Chakraborty N, Holmes-Hampton G, Rusling M, et al (2025)

Delayed Impact of Ionizing Radiation Depends on Sex: Integrative Metagenomics and Metabolomics Analysis of Rodent Colon Content.

International journal of molecular sciences, 26(9):.

There is an escalating need to comprehend the long-term impacts of nuclear radiation exposure since the permeation of ionizing radiation has been frequent in our current societal framework. A system evaluation of the microbes that reside inside a host's colon could meet this knowledge gap since the microbes play major roles in a host's response to stress. Indeed, our past study suggested that these microbes might break their symbiotic association with moribund hosts to form a pro-survival condition exclusive to themselves. In this study, we undertook metagenomics and metabolomics assays regarding the descending colon content (DCC) of adult mice. DCCs were collected 1 month and 6 months after 7 Gy or 7.5 Gy total body irradiation (TBI). The assessment of the metagenomic diversity profile in DCC found a significant sex bias caused by TBI. Six months after 7.5 Gy TBI, decreased Bacteroidetes were replaced by increased Firmicutes in males, and these alterations were reflected in the functional analysis. For instance, a larger number of networks linked to small chain fatty acid (SCFA) synthesis and metabolism were inhibited in males than in females. Additionally, bioenergy networks showed regression dynamics in females at 6 months post-TBI. Increased accumulation of glucose and pyruvate, which are typical precursors of beneficial SCFAs coupled with the activated networks linked to the production of reactive oxygen species, suggest a cross-sex energy-deprived state. Overall, there was a major chronic adverse implication in male mice that supported the previous literature in suggesting females are more radioresistant than males. The sex-biased chronic effects of TBI should be taken into consideration in designing the pertinent therapeutics.

RevDate: 2025-05-22
CmpDate: 2025-05-22

Zhu X, Chen L, Yang P, et al (2025)

Microbiome catalog and dynamics of the Chinese liquor fermentation process.

Bioresource technology, 431:132620.

Fermented food remains poorly understood, largely due to the lack of knowledge about microbes in food fermentation. Here, this study constructed Moutai Fermented Grain Catalog (MTFGC), a representative liquor fermented by one of the most complex fermentations. MTFGC comprised 8,379,551 non-redundant genes and 5,159 metagenome-assembled genomes, with 20% species and 20% genes being novel. Additionally, 25,625 biosynthetic gene clusters (BGCs) and 28 BGC-enriched species were identified. Moreover, the microbial community assembly was deterministic, with significant species and gene changes in early fermentation stages, while stabilizing in later stages. Further BGC-knockout experiments verified Bacillus licheniformis, a BGC-enriched species, employed its BGCs for synthesizing the aroma-related lipopeptide lichenysin. This study has established the largest genetic resource for fermented food, uncovering its uniqueness and high metabolic potential. These findings facilitate the transition potential from traditional fermentation to precision-driven synthetic biology in food systems.

RevDate: 2025-05-16
CmpDate: 2025-05-14

Ma Y, Jiang J, Yang Z, et al (2025)

Changes of gastric microflora and metabolites in patients with chronic atrophic gastritis.

Journal of translational medicine, 23(1):537.

BACKGROUND: Chronic atrophic gastritis (CAG) is related to the body's microbial and metabolic systems. Combined studies of microbiome and metabolomics can clarify the mechanisms of disease occurrence and progression. We used 16S rRNA sequencing, metagenomics sequencing and metabolomics sequencing to depict the landscapes of bacterium and metabolites, construct correlation networks of different bacterium and metabolites describe potential pathogenic mechanisms of chronic atrophic gastritis.

METHODS: The gastric juices of 30 non-atrophic gastritis (NAG) patients and 30 CAG patients were collected. Gastric microflora was analyzed by 16S rRNA sequencing and metagenomics sequencing. Gastric metabolites were analyzed by LC-MS analysis. Different bioinformatics methods were used to analyze the data of microbiome and metabolome, and to analyze the relationship between them.

RESULTS: In atrophic gastritis, bacteria diversity decreased. The genera with a mean decrease in Gini greater than 1.5 included peptostreptococcus, fusobacterium, prevotella, sphingomonas and bacteroides. KEGG pathway included renal cell carcinoma, proximal tubule bicarbonate reclamation, citrate cycle and aldosterone synthesis and secretion with significant enrichment of differential metabolites. Peptostreptococcus, fusobacterium, prevotella and sphingomonas were in pivot positions of the correlation network of differential metabolites and differential bacterium. Viral carcinogenesis, glycine serine and threonine metabolism, RNA polymerase, galactose metabolism and retinol metabolism were enriched in chronic atrophic gastritis based on the metagenomic sequencing data.

CONCLUSION: Peptostreptococcus, fusobacterium, prevotella, sphingomonas and bacteroides were the essential features that distinguish atrophic gastritis from non-atrophic gastritis, and caused disease by altering various metabolic pathways. Viral carcinogenesis, glycine serine and threonine metabolism, RNA polymerase, galactose metabolism and retinol metabolism may be related to the occurrence and progression of CAG.

RevDate: 2025-05-16
CmpDate: 2025-05-14

Zhai R, Zhao C, Chang L, et al (2025)

The gut-liver axis plays a limited role in mediating the liver's heat susceptibility of Chinese giant salamander.

BMC genomics, 26(1):475.

The Chinese giant salamander (CGS, Andrias davidianus), a flagship amphibian species, is highly vulnerable to high temperatures, posing a significant threat under future climate change. Previous research linked this susceptibility to liver energy deficiency, accompanied by shifts in gut microbiota and reduced food conversion rates, raising questions about the role of the gut-liver axis in mediating heat sensitivity. This study investigated the responses of Chinese giant salamander larvae to a temperature gradient (10-30 °C), assessing physiological changes alongside histological, gut metagenomic, and tissue transcriptomic analyses. Temperatures above 20 °C led to mortality, which resulted in delayed growth. Histological and transcriptomic data revealed metabolic exhaustion and liver fibrosis in heat-stressed salamanders, underscoring the liver's critical role in heat sensitivity. While heat stress altered the gut microbiota's community structure, their functional profiles, especially in nutrient absorption and transformation, remained stable. Both gut and liver showed temperature-dependent transcriptional changes, sharing some common variations in actins, heat shock proteins, and genes related to transcription and translation. However, their energy metabolism exhibited opposite trends: it was downregulated in the liver but upregulated in the gut, with the gut showing increased activity in the pentose phosphate pathway and oxidative phosphorylation, potentially countering metabolic exhaustion. Our findings reveal that the liver of the larvae exhibits greater thermal sensitivity than the gut, and the gut-liver axis plays a limited role in mediating thermal intolerance. This study enhances mechanistic understanding of CGS heat susceptibility, providing a foundation for targeted conservation strategies in the face of climate change.

RevDate: 2025-05-16
CmpDate: 2025-05-14

Baek JW, Lim S, Park N, et al (2025)

Extensively acquired antimicrobial-resistant bacteria restructure the individual microbial community in post-antibiotic conditions.

NPJ biofilms and microbiomes, 11(1):78.

In recent years, the overuse of antibiotics has led to the emergence of antimicrobial-resistant (AMR) bacteria. To evaluate the spread of AMR bacteria, the reservoir of AMR genes (resistome) has been identified in environmental samples, hospital environments, and human populations, but the functional role of AMR bacteria and their persistence within individuals has not been fully investigated. Here, we performed a strain-resolved in-depth analysis of the resistome changes by reconstructing a large number of metagenome-assembled genomes from the gut microbiome of an antibiotic-treated individual. Interestingly, we identified two bacterial populations with different resistome profiles: extensively acquired antimicrobial-resistant bacteria (EARB) and sporadically acquired antimicrobial-resistant bacteria, and found that EARB showed broader drug resistance and a significant functional role in shaping individual microbiome composition after antibiotic treatment. Our findings of AMR bacteria would provide a new avenue for controlling the spread of AMR bacteria in the human community.

RevDate: 2025-05-13
CmpDate: 2025-05-13

Connan C, Fromentin S, Benallaoua M, et al (2025)

Associations Among Diet, Health, Lifestyle, and Gut Microbiota Composition in the General French Population: Protocol for the Le French Gut - Le Microbiote Français Study.

JMIR research protocols, 14:e64894 pii:v14i1e64894.

BACKGROUND: Over the past 2 decades, the gut microbiota has emerged as a key player in human health, being involved in many different clinical contexts. Yet, many aspects of the relationship with its host are poorly documented. One obstacle is the substantial variability in wet-laboratory procedures and data processing implemented during gut microbiota studies, which poses a challenge of comparability and potential meta-analysis.

OBJECTIVE: The study protocol described here aimed to better understand the relationship between health, dietary habits, and the observed heterogeneity of gut microbiota composition in the general population. "Le French Gut - Le microbiote français" aimed to collect, sequence, and analyze 100,000 fecal samples from French residents using a high-quality shotgun metagenomic pipeline, complemented with comprehensive health, lifestyle, and dietary metadata.

METHODS: "Le French Gut - Le microbiote français" is a prospective, noninterventional French national study involving individuals, the creation of a biological collection (feces), and the exploitation of data from questionnaires and the National Health Data System (Système National des Données de Santé). This national study is open to all metropolitan French adult residents, excluding those who have undergone a colectomy or digestive stoma, or who have had a colonoscopy or taken antibiotics in the last 3 months. This is a home-based trial in which volunteers complete a questionnaire with insights about their health and habits, and in which stool samples are self-collected. Data analysis is structured into 6 work packages, each focusing on a specific aspect of the gut microbiome, including its composition and associations with lifestyle, quality of life, and health.

RESULTS: This paper outlines the study protocol, with recruitment having started in September 2022 and expected to continue until the end of December 2025. As of January 2025, a total of 20,000 participants have been enrolled. The first scientific publications based on the data analysis are expected by mid-2025.

CONCLUSIONS: "Le French Gut" aims to provide a reference database and new ecosystem tools for understanding the relationship between the gut microbiota, its host, and diet. We expect to be able to find new signatures or targets and promote the design of innovative preventive strategies, personalized nutrition, and precision medicine.

TRIAL REGISTRATION: ClinicalTrials.gov NCT05758961; https://clinicaltrials.gov/study/NCT05758961.

DERR1-10.2196/64894.

RevDate: 2025-05-15
CmpDate: 2025-05-13

Charalambous H, Brown C, Vogazianos P, et al (2025)

Dysbiosis in the Gut Microbiome of Pembrolizumab-Treated Non-Small Lung Cancer Patients Compared to Healthy Controls Characterized Through Opportunistic Sampling.

Thoracic cancer, 16(9):e70075.

BACKGROUND: The gut microbiome influences the host immune system, cancer development and progression, as well as the response to immunotherapy during cancer treatment. Here, we analyse the composition of the gut bacteriome in metastatic Non-Small Cell Lung Cancer (NSCLC) patients receiving Pembrolizumab immunotherapy within a prospective maintenance trial through opportunistic sampling during treatment.

METHODS: The gut microbiome profiles of NSCLC patients were obtained from stool samples collected during Pembrolizumab treatment and analysed with 16S rRNA metagenomics sequencing. Patient profiles were compared to a group of healthy individuals of matching ethnic group, age, sex, BMI and comorbidities.

RESULTS: A significant decrease in the treated patients was observed in two prominent bacterial families of the phylum Firmicutes, Lachnospiraceae and Ruminoccocaceae, which comprised 31.6% and 21.8% of the bacteriome in the healthy group but only 10.9% and 14.2% in the treated patient group, respectively. Species within the Lachnospiraceae and Ruminococcaceae families are known to break down undigested carbohydrates generating short chain fatty acids (SCFA), such as butyrate, acetate and propionate as their major fermentation end-products, which have been implicated in modifying host immune responses. In addition, a significant increase of the Bacteroidacaeae family (Bacteroidetes phylum) was observed from 10.7% in the healthy group to 23.3% in the treated patient group. Moreover, and in agreement with previous studies, a decrease in the Firmicutes to Bacteroidetes ratio in the metastatic NSCLC Pembrolizumab-treated patients was observed.

CONCLUSION: The observed differences indicate dysbiosis and a compromised intestinal health status in the metastatic NSCLC Pembrolizumab-treated patients. This data could inform future studies of immunotherapy treatment responses and modulation of the gut microbiome to minimise dysbiosis prior or concurrent to treatment.

TRIAL REGISTRATION: SWIPE Trial (NCT02705820).

RevDate: 2025-05-21
CmpDate: 2025-05-21

Flörl L, Meyer A, NA Bokulich (2025)

Exploring sub-species variation in food microbiomes: a roadmap to reveal hidden diversity and functional potential.

Applied and environmental microbiology, 91(5):e0052425.

Within-species diversity of microorganisms in food systems significantly shapes community function. While next-generation sequencing (NGS) methods have advanced our understanding of microbiomes at the community level, it is essential to recognize the importance of within-species variation for understanding and predicting the functional activities of these communities. This review highlights the substantial variation observed among microbial species in food systems and its implications for their functionality. We discuss a selection of key species in fermented foods and food systems, highlighting examples of strain-level variation and its influence on quality and safety. We present a comprehensive roadmap of methodologies aimed at uncovering this often overlooked underlying diversity. Technologies like long-read marker-gene or shotgun metagenome sequencing offer enhanced resolution of microbial communities and insights into the functional potential of individual strains and should be integrated with techniques such as metabolomics, metatranscriptomics, and metaproteomics to link strain-level microbial community structure to functional activities. Furthermore, the interactions between viruses and microbes that contribute to strain diversity and community stability are also critical to consider. This article highlights existing research and emphasizes the importance of incorporating within-species diversity in microbial community studies to harness their full potential, advance fundamental science, and foster innovation.

RevDate: 2025-05-21
CmpDate: 2025-05-21

Lopez JA, McKeithen-Mead S, Shi H, et al (2025)

Abundance measurements reveal the balance between lysis and lysogeny in the human gut microbiome.

Current biology : CB, 35(10):2282-2294.e11.

The human gut contains diverse communities of bacteriophage, whose interactions with the broader microbiome and potential roles in human health are only beginning to be uncovered. Here, we combine multiple types of data to quantitatively estimate gut phage population dynamics and lifestyle characteristics in human subjects. Unifying results from previous studies, we show that an average human gut contains a low ratio of phage particles to bacterial cells (∼1:100) but a much larger ratio of phage genomes to bacterial genomes (∼4:1), implying that most gut phage are effectively temperate (e.g., integrated prophage and phage-plasmids). By integrating imaging and sequencing data with a generalized model of temperate phage dynamics, we estimate that phage induction and lysis occur at a low average rate (∼0.001-0.01 per bacterium per day), imposing only a modest fitness burden on their bacterial hosts. Consistent with these estimates, we find that the phage composition of a diverse synthetic community in gnotobiotic mice can be quantitatively predicted from bacterial abundances alone while still exhibiting phage diversity comparable to native human microbiomes. These results provide a foundation for interpreting existing and future studies on links between the gut virome and human health.

RevDate: 2025-05-21
CmpDate: 2025-05-21

Menichini D, De Seta F, Mastrolia SA, et al (2025)

Probiotics in pregnancy and group B streptococcus colonization: A multicentric, randomized, placebo-controlled, double-blind study with a focus on vaginal microbioma.

European journal of obstetrics, gynecology, and reproductive biology, 310:113976.

OBJECTIVE: To evaluate the feasibility and effects of the use of probiotics in pregnancy, starting in the third trimester, on rectovaginal colonization of group B streptococcus (GBS) in women at low obstetric risk.

METHODS: A multicentre, randomized, placebo-controlled, double-blind, parallel-group study was conducted in three tertiary hospitals in northern Italy and included low-risk pregnant women. The intervention consisted of oral administration of two capsules of probiotics or placebo from 30 weeks of pregnancy until 37 weeks of pregnancy. The primary outcome was GBS colonization, evaluated with rectovaginal swabs. In a subgroup, selected at random, changes in the vaginal microbiome after treatment administration were evaluated using 16S Metagenomic Sequencing Library Preparation sequencing and analysis.

RESULTS: In total, 267 pregnant women were randomized to receive probiotics (n = 133) or placebo (n = 134). The two groups were similar at baseline. After treatment, no differences were found in the rates of positive rectovaginal swabs (p = 0.24) and antibiotic administration (p = 0.27). Only one case of postpartum fever (>38 °C) was found in the placebo group. Labour and delivery outcomes and neonatal outcomes were similar in both groups. Analysis of the vaginal microbiota showed that the relative abundance of Lactobacillus spp. was not modified significantly by the probiotics, but the relative abundance of Gardnerella spp. decreased significantly (3.6 ± 7.9 vs 5.5 ± 10.2; p = 0.03). Interestingly, the relative abundance of Lactobacillus spp. reduced significantly in women who subsequently presented with partial rupture of membranes (46.9 ± 43.6 vs 77.7 ± 24.9; p = 0.02).

CONCLUSION: Although the clinical outcomes were unaffected, administration of probiotics led to favourable changes in vaginal microbiota. It remains to be established how this effect could be translated into clinical advantage.

RevDate: 2025-05-21
CmpDate: 2025-05-21

Ouarabi L, Taminiau B, Daube G, et al (2025)

Insights into fungal diversity and dynamics of vaginal mycobiota.

Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology], 56(2):1095-1101.

Although less studied than its bacterial counterpart, the fungal component of the vaginal microbiota plays a critical role in maintaining vaginal homeostasis. Most research on the composition of the vaginal mycobiota has focused on pathological conditions, with relatively few studies involving healthy women. To gain comprehensive insights into the vaginal mycobiota of Algerian women in two different age groups, we performed a targeted metagenomic analysis using ITS2 region sequencing data from 14 vaginal samples collected from healthy women in reproductive and postmenopausal stages. A single dominant fungal species per individual was observed in both young and postmenopausal women, with differences in fungal community composition between the two groups being related to hormone levels. Our results show that Candida and Saccharomyces were the dominant genera in both young and postmenopausal women. Notably, the postmenopausal group had twice as many species, along with the presence of uncommon taxa such as Dipodascus and Fusarium, indicating greater taxonomic diversity. These findings suggest that menopause is associated with increased microbial variability, likely due to hormonal changes that disrupt the vaginal environment. This study paves the way for more extensive analyses involving diverse age groups and ethnic backgrounds.

RevDate: 2025-05-21
CmpDate: 2025-05-21

da Silva Pereira M, Alcantara LM, de Freitas LM, et al (2025)

Microbial Rumen proteome analysis suggests Firmicutes and Bacteroidetes as key producers of lignocellulolytic enzymes and carbohydrate-binding modules.

Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology], 56(2):817-833.

Lignocellulosic biomass, rich in cellulose, hemicellulose, and lignin, offers a sustainable source for biofuels and and production of other materials such as polymers, paper, fabrics, bioplastics and biofertilizers. However, its complex structure hinders efficient conversion. Chemical, enzymatic, and microbial methods aim to unlock the trapped sugars and phenols. The rumen microbiome, a fascinating ecosystem within ruminant animals, holds particular promise. The Hungate 1000 project sequenced 410 microbial genomes from the rumen, enabling in silico screening for lignocellulolytic enzymes. This approach saves time and resources, supporting the development of sustainable bioconversion technologies aligned with the UN's 2030 agenda goals. Analysis of these 410 predicted proteomes revealed diverse carbohydrate-active enzymes (CAZymes) and carbohydrate-binding modules (CBMs) across various microorganisms. Notably, Firmicutes and Bacteroidetes dominated CAZyme and CBM production, suggesting collaborative efforts among different phyla during degradation. The presence of CBM50 and chitinases hints at the ability to utilize chitin from fungal cell walls. Interestingly, the absence of ligninolytic auxiliary activity enzymes reaffirms the rumen microbiome's incapability of directly degrading lignin. However, enzymes facilitating the loosening of the cell wall by cleaving lignin-hemicellulose linkages were identified. This suggests a strategy for making cellulose more accessible to hydrolytic enzymes. This study highlights the intricate relationship between rumen microbes, contributing necessary enzymes for plant cell wall deconstruction in this unique environment. Additionally, it underlines the power of in silico techniques for analyzing big data, paving the way for advancements in sustainable bioconversion.

RevDate: 2025-05-21
CmpDate: 2025-05-21

Huang Y, Xu W, Dong W, et al (2025)

Anti-diabetic effect of dicaffeoylquinic acids is associated with the modulation of gut microbiota and bile acid metabolism.

Journal of advanced research, 72:17-35.

INTRODUCTION: The human gut microbiome plays a pivotal role in health and disease, notably through its interaction with bile acids (BAs). BAs, synthesized in the liver, undergo transformation by the gut microbiota upon excretion into the intestine, thus influencing host metabolism. However, the potential mechanisms of dicaffeoylquinic acids (DiCQAs) from Ilex kudingcha how to modulate lipid metabolism and inflammation via gut microbiota remain unclear.

OBJECTIVES AND METHODS: The objectives of the present study were to investigate the regulating effects of DiCQAs on diabetes and the potential mechanisms of action. Two mice models were utilized to investigate the anti-diabetic effects of DiCQAs. Additionally, analysis of gut microbiota structure and functions was conducted concurrently with the examination of DiCQAs' impact on gut microbiota carrying the bile salt hydrolase (BSH) gene, as well as on the enterohepatic circulation of BAs and related signaling pathways.

RESULTS: Our findings demonstrated that DiCQAs alleviated diabetic symptoms by modulating gut microbiota carrying the BSH gene. This modulation enhanced intestinal barrier integrity, increased enterohepatic circulation of conjugated BAs, and inhibited the farnesoid X receptor-fibroblast growth factor 15 (FGF15) signaling axis in the ileum. Consequently, the protein expression of hepatic FGFR4 fibroblast growth factor receptor 4 (FGFR4) decreased, accompanied by heightened BA synthesis, reduced hepatic BA stasis, and lowered levels of hepatic and plasma cholesterol. Furthermore, DiCQAs upregulated glucolipid metabolism-related proteins in the liver and muscle, including v-akt murine thymoma viral oncogene homolog (AKT)/glycogen synthase kinase 3-beta (GSK3β) and AMP-activated protein kinase (AMPK), thereby ameliorating hyperglycemia and mitigating inflammation through the down-regulation of the MAPK signaling pathway in the diabetic group.

CONCLUSION: Our study elucidated the anti-diabetic effects and mechanism of DiCQAs from I. kudingcha, highlighting the potential of targeting gut microbiota, particularly Acetatifactor sp011959105 and Acetatifactor muris carrying the BSH gene, as a therapeutic strategy to attenuate FXR-FGF15 signaling and ameliorate diabetes.

RevDate: 2025-05-13
CmpDate: 2025-05-13

Park C, Park J, Chang D, et al (2025)

Development of reference-based model for improved analysis of bacterial community.

Food research international (Ottawa, Ont.), 211:116380.

Probiotic bacteria play a vital role in maintaining gut microbial homeostasis and are widely used in various commercial products. Although 16S rRNA amplicon-based next-generation sequencing (NGS) is commonly used to analyze probiotic products, biases can arise from various 16S rRNA amplification regions, sequencing platforms, and library kits. In this study, a reference-based bias correction model was developed to correct sequencing biases. The model was validated using eight mock communities and 12 commercial products, which were analyzed across multiple NGS platforms and various 16S rRNA regions. Specific primer-probe assays were developed for accurate bacterial quantification, and their specificity was validated and used in conjunction with droplet digital PCR (ddPCR) to establish initial bacterial ratios within communities. Analysis of the mock communities revealed platform- and region-specific biases, with specific species consistently over- or under-represented. Similarly, commercial product analyses have shown biased outcomes owing to varying sequencing protocols. The correction model, based on PCR efficiencies from the reference communities, successfully corrected biased ratios across different amplification regions and platforms to achieve results that closely matched the proportions predicted by ddPCR. The model effectively corrected the biases arising from the different polymerases. Notably, partial references containing approximately 40 % of the species achieved correction results that were comparable to those of the complete references. This approach demonstrates the potential for improving microbiome analysis accuracy within predictable ranges, and could serve as a model for addressing sequencing bias in metagenomic research.

RevDate: 2025-05-13
CmpDate: 2025-05-13

Wang S, Zheng C, Bu C, et al (2025)

Role of sn-2 palmitate on the development of the infant gut microbiome: A metagenomic insight.

Food research international (Ottawa, Ont.), 211:116488.

The infant gut microbiome, which develops from birth, has profound and lasting effects on human health. Its establishment in early life is influenced by events such as delivery mode and feeding type. This study examined the effects of formula milk enriched with sn-2 palmitate on the gut microbiota of healthy term infants. We conducted a 16-week comparative analysis of three feeding groups: infants receiving high sn-2 palmitate formula (n = 30), regular vegetable oil formula (n = 32), and breast milk (n = 30). Using shotgun metagenomic sequencing of fecal samples, we performed a comprehensive assessment of the gut microbiota. While overall microbial composition and diversity were comparable across groups, the functional profile of the microbiome in infants receiving sn-2 palmitate-enriched formula more closely resembled that of breastfed infants compared to the control formula group. This similarity extended to microbial species interactions, virulence gene abundance, and metabolic pathway expression patterns. In addition, sn-2 palmitate promoted the proliferation of Bifidobacterium breve and enhanced the robustness of the gut microbial ecology. Notably, the phylogenetic analysis of B. breve strains in the sn-2 palmitate group showed closer alignment with the breastfed group compared to the control group. These findings suggest that sn-2 palmitate-enriched formula may confer gut microbiota functional benefits that more closely resemble those of breast milk compared to control formula milk. This study provides scientific evidence for the development of future functional infant formulas.

RevDate: 2025-05-13
CmpDate: 2025-05-13

Luo Y, Tang R, Y Huang (2025)

Differences in structure, antioxidant capacity and gut microbiota modulation of red raspberry pectic polysaccharides extracted by different methods.

Food research international (Ottawa, Ont.), 211:116474.

Red raspberries are associated with various health benefits, with pectic polysaccharides as their primary component and potential key contributor to these effects. This study aimed to evaluate the antioxidant and prebiotic potential of four red raspberry pectic polysaccharides (RP)-EN-RP (enzyme-assisted extraction), AC-RP (acid-assisted extraction), AL-RP (alkali-assisted extraction), and US-RP (ultrasound-assisted extraction)-and to elucidate the relationship between their structure and function. AC-RP and US-RP contained higher proportions of homogalacturonan (HG) at 50.92 % and 53.10 %, respectively, while EN-RP and AL-RP exhibited higher proportions of rhamnogalacturonan-I (RG-I) at 63.89 % and 43.37 %, respectively. All four polysaccharides demonstrated significant antioxidant and prebiotic properties. AL-RP exhibited the strongest DPPH radical scavenging activity, while US-RP showed the highest hydroxyl radical scavenging ability. These pectic polysaccharides were highly fermentable, significantly modulating gut microbiota composition and promoting the production of propionic acid, particularly EN-RP and AL-RP. Compared to the blank group, RP intervention significantly enriched Bacteroides, Phocaeicola, Bifidobacterium, Limosilactobacillus, and Paraprevotella. Carbohydrate-active enzyme genes in metagenomes revealed that glycoside hydrolases played a vital role in the degradation and utilization of red raspberry polysaccharides. Furthermore, correlation analysis indicated that a higher RG-I proportion and an elevated Rha/GalA ratio enhanced the abundance of certain beneficial microbial species and increased propionic acid production. These findings advance the understanding of the structure-function relationship of natural pectic polysaccharides and highlight their potential for tailoring gut microbiota and promoting health through precise dietary interventions.

RevDate: 2025-05-12
CmpDate: 2025-05-13

Wang L, Chen Y, Wang Q, et al (2025)

Microbial imbalances linked to early pregnancy loss: a comparative analysis of vaginal microbiota.

The journal of maternal-fetal & neonatal medicine : the official journal of the European Association of Perinatal Medicine, the Federation of Asia and Oceania Perinatal Societies, the International Society of Perinatal Obstetricians, 38(1):2496787.

OBJECTIVE: To explore the role and related functions of vaginal microbiota in early pregnancy loss.

METHODS: This study was a case-control study with a comparison group (reference group). We recruited 178 women, including 73 who had experienced at least one early clinical pregnancy loss and 105 patients with one live birth and no history of pregnancy loss. Data on demographics, disease history, menstrual and reproductive history was collected. The case group patients were sampled immediately upon presenting with pregnancy loss at their first visit. The reference group patients underwent samples when they chose to participate voluntarily. All vaginal discharge was performed DNA Preparation and Metagenomics Sequencing. DNA extraction was performed using the phenol/trichloromethane method and the DNA fragments were then size-selected to 300-700 bp using magnetic beads. The selected fragments were repaired and ligated with indexed adaptors. The captured DNA was amplified again by PCR and circularized to create a single-stranded circular (ssCir) library. The ssCir library was subsequently amplified through rolling circle amplification (RCA) to produce DNA nanoballs (DNBs). The DNBs were then loaded onto a flow cell and sequenced using the DNBSEQ Platform. Nonparametric tests, including Kruskal-Wallis and Wilcoxon tests, were employed. Relative abundance between groups was compared, and differential species selection was performed using the LEfSe software with linear discriminant analysis.

RESULTS: 1. PCoA analysis based on Bray-Curtis distances at the species level revealed a difference between the groups (p = 0.011). At the genus level, α-diversity, assessed using the Shannon, Simpson, and Inverse Simpson indices, indicated higher bacterial richness and diversity in the control group (Shannon: mean 0.554 vs. 0.383, p = 0.0044; Simpson: mean 0.254 vs. 0.179, p = 0.0043; Inverse Simpson: mean 1.636 vs. 1.414, p = 0.0043); At the genus level, 107 microbial genera were identified, 18 of which displayed statistically significant differences. At the species level, 23 microbial species showed significant differences between the two groups. 2. We analyzed the differences in the most abundant phyla, genera, and species, with a particular focus on the top 20 most abundant genera and species. Firmicutes and Proteobacteria were significantly more prevalent among patients with pregnancy loss (PL). Among the top 20 most abundant genera, Streptococcus and Porphyromonas were significantly more abundant in patients with PL, whereas Bifidobacterium was significantly more prevalent in the reference group. Among the 20 most abundant species, Lactobacillus crispatus was significantly more prevalent in patients with PL, whereas common in the control group. 3. Principal Coordinates Analysis (PCoA) of Bray-Curtis distances, highlight their distinct clustering patterns, suggesting a notable difference between the metabolic pathways of the two groups. Key pathways with a negative correlation to PL include those related to amino acid biosynthesis, lipid metabolism, and nucleotide biosynthesis.

CONCLUSION: Our study highlights the association between vaginal microbiota dysbiosis and EPL, identifying specific microbial taxa that may contribute to pregnancy loss. These findings underscore the importance of the vaginal microbiome in reproductive health and open up new avenues for research into microbiome-based diagnostics and therapies. By integrating microbial, immune, and environmental data, future research has the potential to uncover the mechanisms underlying EPL and develop targeted interventions to improve pregnancy outcomes.

RevDate: 2025-05-14
CmpDate: 2025-05-12

Schultz J, Jamil T, Sengupta P, et al (2025)

Genomic insights into novel extremotolerant bacteria isolated from the NASA Phoenix mission spacecraft assembly cleanrooms.

Microbiome, 13(1):117.

BACKGROUND: Human-designed oligotrophic environments, such as cleanrooms, harbor unique microbial communities shaped by selective pressures like temperature, humidity, nutrient availability, cleaning reagents, and radiation. Maintaining the biological cleanliness of NASA's mission-associated cleanrooms, where spacecraft are assembled and tested, is critical for planetary protection. Even with stringent controls such as regulated airflow, temperature management, and rigorous cleaning, resilient microorganisms can persist in these environments, posing potential risks for space missions.

RESULTS: During the Phoenix spacecraft mission, genomes of 215 bacterial isolates were sequenced and based on overall genome-related indices, 53 strains belonging to 26 novel species were recognized. Metagenome mapping indicated less than 0.1% of the reads associated with novel species, suggesting their rarity. Genes responsible for biofilm formation, such as BolA (COG0271) and CvpA (COG1286), were predominantly found in proteobacterial members but were absent in other non-spore-forming and spore-forming species. YqgA (COG1811) was detected in most spore-forming members but was absent in Paenibacillus and non-spore-forming species. Cell fate regulators, COG1774 (YaaT), COG3679 (YlbF, YheA/YmcA), and COG4550 (YmcA, YheA/YmcA), controlling sporulation, competence, and biofilm development processes, were observed in all spore-formers but were missing in non-spore-forming species. COG analyses further revealed resistance-conferring proteins in all spore-formers (n = 13 species) and eight actinobacterial species, responsible for enhanced membrane transport and signaling under radiation (COG3253), transcription regulation under radiation stress (COG1108), and DNA repair and stress responses (COG2318). Additional functional analysis revealed that Agrococcus phoenicis, Microbacterium canaveralium, and Microbacterium jpeli contained biosynthetic gene clusters (BGCs) for ε-poly-L-lysine, beneficial in food preservation and biomedical applications. Two novel Sphingomonas species exhibited for zeaxanthin, an antioxidant beneficial for eye health. Paenibacillus canaveralius harbored genes for bacillibactin, crucial for iron acquisition. Georgenia phoenicis had BGCs for alkylresorcinols, compounds with antimicrobial and anticancer properties used in food preservation and pharmaceuticals.

CONCLUSION: Despite stringent decontamination and controlled environmental conditions, cleanrooms harbor unique bacterial species that form biofilms, resist various stressors, and produce valuable biotechnological compounds. The reduced microbial competition in these environments enhances the discovery of novel microbial diversity, contributing to the mitigation of microbial contamination and fostering biotechnological innovation. Video Abstract.

RevDate: 2025-05-20
CmpDate: 2025-05-20

Yang X, Zhang Y, Xu Y, et al (2025)

Microbial Disturbances Caused by Pesticide Exposure and Their Predictive Implications for Gestational Diabetes Mellitus.

Environmental science & technology, 59(19):9449-9460.

Previous studies have suggested that pesticide exposure and gut microbiome alterations are associated with gestational diabetes mellitus (GDM) risk. Understanding the complex interactive effect of these factors on GDM is essential. In a cohort of 852 pregnant women, we assessed pesticide levels in serum and analyzed the gut microbiota using 16S rRNA and shotgun metagenomic sequencing. We explored the interactions between pesticides and gut microbiota, assessed their roles in GDM development, and proposed a predictive model based on identified biomarkers. We identified an environmental risk score (ERS), denoting the pesticide mixture level significantly associated with GDM, with the gut microbiota, particularly involving the Dorea branch, playing a crucial mediating role. In addition, we found an interactive effect of pesticide exposure and gut microbiota on GDM risk. Notably, low Prevotella enrichment combined with high ERS arisen from pesticide levels led to a 10.36-fold increased GDM risk. The identified pesticide and gut microbial biomarkers achieved high predictive accuracy for GDM (AUC: 0.833, 95% CI: 0.748-0.918). Collectively, maternal pesticide exposure may induce disrupted microbiome-dependent glycemic alteration, necessitating future assessment of clinical implications. Potential GDM markers can serve as targets for therapeutic intervention caused by pesticides, leading to prevention.

RevDate: 2025-05-20
CmpDate: 2025-05-20

Lindner BG, Graham KE, Phaneuf JR, et al (2025)

SourceApp: A Novel Metagenomic Source Tracking Tool that can Distinguish between Fecal Microbiomes Using Genome-To-Source Associations Benchmarked Against Mixed Input Spike-In Mesocosms.

Environmental science & technology, 59(19):9507-9516.

Methodologies utilizing metagenomics are attractive to fecal source tracking (FST) aims for assessing the presence and proportions of various fecal inputs simultaneously. Yet, compared to established culture- or PCR-based techniques, metagenomic approaches for these purposes are rarely benchmarked or contextualized for practice. We performed shotgun sequencing experiments (n = 35) of mesocosms constructed from the water of a well-studied recreational and drinking water reservoir spiked with various fecal (n = 6 animal sources, 3 wastewater sources, and 1 septage source) and synthetic microbiome spike-ins (n = 1) introduced at predetermined cell concentrations to simulate fecal pollution events of known composition. We built source-associated genome databases using publicly available reference genomes and metagenome assembled genomes (MAGs) recovered from short- and long-read sequencing of the fecal spike-ins, and then created an associated bioinformatic tool, called SourceApp, for inferring source attribution and apportionment by mapping the metagenomic data to these genome databases. SourceApp's performance varied substantially by source, with cows being underestimated due to under sampling of cow fecal microbiomes. Parameter tuning revealed sensitivity and specificity near 0.90 overall, which exceeded all alternative tools. SourceApp can assist researchers with analyzing and interpreting shotgun sequencing data and developing standard operating procedures on the frontiers of metagenomic FST.

RevDate: 2025-05-20
CmpDate: 2025-05-20

Chen Z, Zhang Z, Nie BN, et al (2025)

Temporal network analysis of gut microbiota unveils aging trajectories associated with colon cancer.

mSystems, 10(5):e0118824.

UNLABELLED: The human gut microbiome's role in colorectal cancer (CRC) pathogenesis has gained increasing recognition. This study aimed to delineate the microbiome characteristics that distinguish CRC patients from healthy individuals, while also evaluating the influence of aging, through a comprehensive metagenomic approach. The study analyzed a cohort of 80 CRC patients and 80 matched healthy controls, dividing participants into a normal and a CRC group, further categorized by age into young, middle-aged, and old-aged subgroups. Extensive metagenomic sequencing of fecal samples allowed for the exploration of both the structural and functional profiles of the microbiome, with findings validated in an independent cohort to ensure robustness. Our results highlight notable differences in microbiome composition between CRC patients and healthy individuals, which exhibit age-dependent variations. Specifically, a higher prevalence of pathogenic bacteria, such as Bacteroides vulgatus, known to drive inflammation and carcinogenesis, was observed in CRC patients, alongside a reduction in beneficial microbes, including Lactobacillus. Functionally, the CRC-associated microbiome showed an increase in pathways related to DNA repair, cell cycle regulation, and metabolic activities, such as the Citrate cycle and Galactose metabolism, underscoring distinct microbial alterations in CRC patients that could influence disease onset and progression. These insights lay a foundation for future research into microbiome-based diagnostics and treatments for CRC.

IMPORTANCE: This study underscores the critical role of the gut microbiome in colorectal cancer (CRC) pathogenesis, particularly in the context of aging. By identifying age-specific microbial biomarkers and functional pathways associated with CRC, our findings provide novel insights into how microbiome composition and metabolic activities influence disease progression. These discoveries pave the way for developing personalized microbiome-based diagnostic tools and therapeutic strategies, potentially improving CRC prevention and treatment outcomes across different age groups. Understanding these microbial dynamics could also inform interventions targeting gut microbiota to mitigate CRC risk and progression.

RevDate: 2025-05-20
CmpDate: 2025-05-20

Zhou Z, Ma Y, Zhang D, et al (2025)

Microbiome and fragmentation pattern of blood cell-free DNA and fecal metagenome enhance colorectal cancer micro-dysbiosis and diagnosis analysis: a proof-of-concept study.

mSystems, 10(5):e0027625.

Colorectal cancer (CRC) is the third most common cancer, and it can be prevented by performing early screening. As a hallmark of cancer, the human microbiome plays important roles in the occurrence and development of CRC. Recently, the blood microbiome has been proposed as an effective diagnostic tool for various diseases, yet its performance on CRC deserves further exploration. In this study, 133 human feces and 120 blood samples are collected, including healthy individuals, adenoma patients, and CRC patients. The blood cfDNA and fecal genome are subjected to shotgun metagenome sequencing. After removing human sequences, the microbial sequences in blood are analyzed. Based on the differential microbes and functions, random forest (RF) models are constructed for adenoma and CRC diagnosis. The results show that alterations of blood microbial signatures can be captured under low coverage (even at 3×). RF diagnostic models based on blood microbial markers achieve high area under the curve (AUC) values for adenoma patients (0.8849) and CRC patients (0.9824). When the fragmentation pattern is combined with microbial and KEGG markers, higher AUC values are obtained. Furthermore, compared to the blood microbiome, the fecal microbiome shows a different community composition, whereas their changes in KEGG pathways are similar. Pathogenic bacteria Fusobacterium nucleatum (F. nucleatum) in feces increased gradually from the healthy group to the adenoma and CRC groups. Additionally, F. nucleatum in feces and blood shows a positive correlation in CRC patients. Cumulatively, the integration of blood microbiome and fragmentation pattern is promising for CRC diagnosis.IMPORTANCEThe cell-free DNA of the human microbiome can enter the blood and can be used for cancer diagnosis, whereas its diagnostic potential in colorectal cancer and association with gut microbiome has not been explored. The microbial sequences in blood account for less than 1% of the total sequences. The blood microbial composition, KEGG functions, and fragmentation pattern are different among healthy individuals, adenoma patients, and CRC patients. Machine learning models based on these differential characteristics achieve high diagnostic accuracy, especially when they are integrated with fragmentation patterns. The great difference between fecal and blood microbiomes indicates that microbial sequences in blood may originate from various organs. Therefore, this study provides new insights into the community composition and functions of the blood microbiome of CRC and proposes an effective non-invasive diagnostic tool.

RevDate: 2025-05-20
CmpDate: 2025-05-20

Dai X, Cao Y, Li L, et al (2025)

Gut microbiome and metabolome profiles in renal allograft rejection from multiomics integration.

mSystems, 10(5):e0162624.

UNLABELLED: The gut microbiome and metabolome play crucial roles in renal allograft rejection progression. Integrated multiomics analyses may provide a comprehensive understanding of specific underlying mechanisms, which remain elusive. This study aimed to identify new approaches for clinical renal allograft rejection diagnosis and treatment. Thirty-five patients were divided into three groups: the rejection (n = 16), dysfunction (n = 7), and control (n = 12) groups. Metagenomic sequencing and nontargeted metabolomics were used to analyze stool and plasma samples. Significant microbiota, metabolites, and signaling pathways were identified. LASSO regression was used to construct a diagnostic model, and its diagnostic value was assessed via receiver operating characteristic curves. The microbiota composition and the related genes in the rejection group significantly differed from that in the dysfunction and control groups at the phylum, genus, and species levels (P < 0.001). The core species in the rejection group networks were Escherichia coli and Ruminococcus gnavus, while core species in the dysfunction group networks were Faecalibacterium prausnitzii and Bacteroides ovatus. The balance of specific microbial species was associated with kidney function in rejection patients. Spearman analysis revealed that specific differential species like Agathobaculum butyriciproducens and Gemmiger qucibialis were closely linked to the levels of serum 4-pyridoxic acid, 4-acetamidobutanoate, and fecal tryptamine from specific differential pathways. Finally, we constructed four clinical models to distinguish the rejection and dysfunction groups, and the model had excellent diagnostic performance. Altered gut microbiota may contribute to changes in metabolic pathway activity and metabolite abundance in rejection and dysfunction patients, which are strongly correlated with host immunological rejection. The diagnostic model, developed based on the gut microbiota and metabolites, has high clinical value for diagnosing renal rejection.

IMPORTANCE: This study aimed to screen new markers for non-invasive diagnosis by the gut microbiome and metabolome analysis, providing new insights into rejection mechanisms and identifying new approaches for clinical renal allograft rejection diagnosis.

RevDate: 2025-05-20
CmpDate: 2025-05-20

Žuštra A, Leonard VR, Holland LA, et al (2025)

Longitudinal dynamics of the nasopharyngeal microbiome in response to SARS-CoV-2 Omicron variant and HIV infection in Kenyan women and their children.

mSystems, 10(5):e0156824.

UNLABELLED: The nasopharynx and its microbiota are implicated in respiratory health and disease. The interplay between viral infection and the nasopharyngeal microbiome is an area of increased interest. The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiological agent of the coronavirus disease 2019 pandemic, on the nasopharyngeal microbiome among individuals living with HIV is not fully characterized. Here, we describe the nasopharyngeal microbiome before, during, and after SARS-CoV-2 infection in a longitudinal cohort of Kenyan women (21 living with HIV and 14 HIV-uninfected) and their children (18 HIV-exposed, uninfected and 7 HIV-unexposed, uninfected) between September 2021 and March 2022. We show using genomic epidemiology that mother and child dyads were infected with the same strain of the SARS-CoV-2 Omicron variant that spread rapidly across Kenya. We used metagenomic sequencing to characterize the nasopharyngeal microbiome of 20 women and children infected with SARS-CoV-2, six children negative for SARS-CoV-2 but experiencing respiratory symptoms, and 34 timepoint-matched SARS-CoV-2-negative mothers and children. Since individuals were sampled longitudinally before and after SARS-CoV-2 infection, we could characterize the short- (within a week of infection) and longer- (average of 38 days post-infection) term impact of SARS-CoV-2 infection on the nasopharyngeal microbiome. We found that mothers and children had significantly different microbiome composition and bacterial load (P-values < 0.0001). In both mothers and children, the nasopharyngeal microbiome did not differ before and after SARS-CoV-2 infection, regardless of HIV exposure status. Our results indicate that the nasopharyngeal microbiome is resilient to SARS-CoV-2 infection and was not significantly modified by HIV.

IMPORTANCE: The nasopharyngeal microbiome plays an important role in human health. The degree of impact that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has on the nasopharyngeal microbiome varies among studies and may be influenced by diverse SARS-CoV-2 variants and variations in the microbiome between individuals. Our results show that the nasopharyngeal microbiome was not altered substantially by SARS-CoV-2 infection nor by HIV infection in mothers or HIV exposure in children. Our findings highlight the resilience of the nasopharyngeal microbiome after SARS-CoV-2 infection. These findings advance our understanding of the nasopharyngeal microbiome and its interactions with viral infections.

RevDate: 2025-05-20
CmpDate: 2025-05-20

Shamash M, Sinha A, CF Maurice (2025)

Improving gut virome comparisons using predicted phage host information.

mSystems, 10(5):e0136424.

UNLABELLED: The human gut virome is predominantly made up of bacteriophages (phages), viruses that infect bacteria. Metagenomic studies have revealed that phages in the gut are highly individual specific and dynamic. These features make it challenging to perform meaningful cross-study comparisons. While several taxonomy frameworks exist to group phages and improve these comparisons, these strategies provide little insight into the potential effects phages have on their bacterial hosts. Here, we propose the use of predicted phage host families (PHFs) as a functionally relevant, qualitative unit of phage classification to improve these cross-study analyses. We first show that bioinformatic predictions of phage hosts are accurate at the host family level by measuring their concordance to Hi-C sequencing-based predictions in human and mouse fecal samples. Next, using phage host family predictions, we determined that PHFs reduce intra- and interindividual ecological distances compared to viral contigs in a previously published cohort of 10 healthy individuals, while simultaneously improving longitudinal virome stability. Lastly, by reanalyzing a previously published metagenomics data set with >1,000 samples, we determined that PHFs are prevalent across individuals and can aid in the detection of inflammatory bowel disease-specific virome signatures. Overall, our analyses support the use of predicted phage hosts in reducing between-sample distances and providing a biologically relevant framework for making between-sample virome comparisons.

IMPORTANCE: The human gut virome consists mainly of bacteriophages (phages), which infect bacteria and show high individual specificity and variability, complicating cross-study comparisons. Furthermore, existing taxonomic frameworks offer limited insight into their interactions with bacterial hosts. In this study, we propose using predicted phage host families (PHFs) as a higher-level classification unit to enhance functional cross-study comparisons. We demonstrate that bioinformatic predictions of phage hosts align with Hi-C sequencing results at the host family level in human and mouse fecal samples. We further show that PHFs reduce ecological distances and improve virome stability over time. Additionally, reanalysis of a large metagenomics data set revealed that PHFs are widespread and can help identify disease-specific virome patterns, such as those linked to inflammatory bowel disease.

RevDate: 2025-05-14
CmpDate: 2025-05-12

Ding Y, Ke J, Hong T, et al (2025)

Microbial diversity and ecological roles of halophilic microorganisms in Dingbian (Shaanxi, China) saline-alkali soils and salt lakes.

BMC microbiology, 25(1):287.

Halophilic microorganisms abound in numerous hypersaline environments, such as salt lakes, salt mines, solar salterns, and salted seafood. In the northwest of Dingbian county (Shaanxi province, China), there exists a belt of hypersaline habitats extending from the west to the north consisting of saline-alkali soil and salt lakes. Theoretically, such a hypersaline environment has a high probability of containing abundant halophilic archaea communities. Nevertheless, there is nearly no systematic research on halophilic archaea in this area. Here, we employed a combination of culture-dependent and culture-independent methods to analyze the collected samples. The high-throughput sequencing results of the archaeal 16S rRNA gene indicated that the richness of halophilic archaea in saline-alkali soils was significantly higher than that in salt lakes. In saline-alkali soils, the Natronomonas genus of archaea was more predominant compared to other genera, while in salt lakes, the Halonotius, Halorubrum, and Haloarcula genera of archaea had relatively higher abundances. However, the dominant families of halophilic archaea in both environments were mainly Haloferacaceae (30.96-72%), Halomicrobiaceae (17-53.19%) and Nanosalinaceae (1-19.08%). Based on the outcomes of pure culture experiments, a total of 26 genera and 98 strains were identified. Among the identified halophilic microorganisms, the predominant species were Halorubrum and Fodinibius, accounting for 33.67% and 13.27%, respectively. The remainder were mostly low-abundance groups within the community, and 22 potential novel taxa were discovered. Additionally, metagenomic technology was employed in our research. The analysis results demonstrated that the microorganisms in this area possess metabolic pathways capable of degrading various pollutants such as atrazine, methane, and dioxins, suggesting that some microorganisms in this area play a positive role in environmental remediation. This study roughly reveals the diversity composition and dominant species of halophilic archaea in these hypersaline environments and provides a scientific basis for the possible ecological functions of microorganisms in this area during long-term survival. It also offers scientific evidence for the development and utilization of halophilic microbial resources and ecological protection.

RevDate: 2025-05-14
CmpDate: 2025-05-12

Zhang X, Zhong R, Wu J, et al (2025)

Dietary selection of distinct gastrointestinal microorganisms drives fiber utilization dynamics in goats.

Microbiome, 13(1):118.

BACKGROUND: Dietary fiber is crucial to animal productivity and health, and its dynamic utilization process is shaped by the gastrointestinal microorganisms in ruminants. However, we lack a holistic understanding of the metabolic interactions and mediators of intestinal microbes under different fiber component interventions compared with that of their rumen counterparts. Here, we applied nutritional, amplicon, metagenomic, and metabolomic approaches to compare characteristic microbiome and metabolic strategies using goat models with fast-fermentation fiber (FF) and slow-fermentation fiber (SF) dietary interventions from a whole gastrointestinal perspective.

RESULTS: The SF diet selected fibrolytic bacteria Fibrobacter and Ruminococcus spp. and enriched for genes encoding for xylosidase, endoglucanase, and galactosidase in the rumen and cecum to enhance cellulose and hemicellulose utilization, which might be mediated by the enhanced microbial ATP production and cobalamin biosynthesis potentials in the rumen. The FF diet favors pectin-degrading bacteria Prevotella spp. and enriched for genes encoding for pectases (PL1, GH28, and CE8) to improve animal growth. Subsequent SCFA patterns and metabolic pathways unveiled the favor of acetate production in the rumen and butyrate production in the cecum for SF goats. Metagenomic binning verified this distinct selection of gastrointestinal microorganisms and metabolic pathways of different fiber types (fiber content and polysaccharide chemistry).

CONCLUSIONS: These findings provide novel insights into the key metabolic pathways and distinctive mechanisms through which dietary fiber types benefit the host animals from the whole gastrointestinal perspective. Video Abstract.

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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.

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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.

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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.

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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.

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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.

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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

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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.

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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.

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