The gut microbiome of cattle suppresses pathogens and aids host immunity. However, the gut microbiome of newborn calves is still developing; therefore, diarrhea caused by pathogen infection is common. Rapid changes in the gut microbiome due to diarrhea have a significant impact on the health and growth of calves. Until recently, there have been few studies on the changes in the gut microbiome following infection with major digestive pathogens that cause diarrhea in Hanwoo (Korean indigenous cattle) calves. Therefore, this study was conducted to identify viral digestive pathogens that cause severe diarrhea in Hanwoo calves. Seven normal calves without diarrhea and eight calves with diarrhea were selected, and their feces were collected to analyze pathogens and the gut microbiome. Bovine rotavirus (BRV) and bovine coronavirus (BCoV) were detected in the feces of the calves with diarrhea. There was no significant difference in the alpha diversity of the microbiome between normal calves and calves infected with viruses; however, a significant decrease in NPShannon and Shannon indices and a significant increase in Simpson index were observed in calves infected with BRV compared to calves infected with BCoV. In addition, beta diversity of the microbiome differed distinctly between normal calves and calves infected with BRV or BCoV. At the class level, BRV infection increased Gammaproteobacteria and Actinobacteria, whereas BCoV infection increased Clostridia and decreased Bacilli. In addition, the abundance of Lactobacillus was significantly reduced upon infection with BRV and BCoV. In this study, we confirmed the differences in the gut microbiome based on viral pathogens causing diarrhea in Hanwoo calves. The results of pathogen-targeting research are expected to be helpful in preventing common pathogens in calves.
Microbiome research is a dynamic, rapidly growing, and interdisciplinary field that generates valuable insights across the human health, agricultural, and environmental sectors. Despite this growth, gaps remain in educational content and professional development opportunities specifically tailored for microbiome science rather than traditional microbiology. The National Microbiome Data Collaborative (NMDC) has developed a Microbiome Science Certificate Program aimed at undergraduates but available to any learner or researcher interested in this field. The curriculum includes 12 modules to further technical knowledge, as well as practical and professional skills. The modules each include prepared slide decks, recorded lectures, resource documents, expert interviews, reading assignments, knowledge assessments, and an overall glossary. The modular content can be readily applied within the classroom as a stand-alone semester-long course or as supplementary to existing curricula. An asynchronous, online, certificate-granting implementation of the content is available through the American Society for Microbiology. We have outlined future laboratory, workforce development, and data science "mini-modules" that can be further developed with the help of educators. Improvements will be made to the program content based on feedback from learners and educators. This program aims to promote practical skills to empower the next generation of microbiome researchers.
The adaptation of complex, host-associated microbiomes to environmental perturbations is a critical determinant of ecosystem stability and resilience to climate change, as exemplified in ruminants. While single-microbe RNA sequencing advances community interrogation, complex microbial cell walls severely constrain unbiased single-cell transcriptomic profiling in the rumen. In this study, we developed an optimized 25 min time-resolved enzymatic lysis strategy using smRandom-seq to map the sheep rumen microbiome at single-cell resolution. By profiling 60 748 cells across 21 samples, we captured previously intractable lineages, resolving the transcriptional states of 213 genera and 662 species, achieving a physiologically relevant 0.303% recovery of methanogenic archaea. Unsupervised clustering partitioned the ecosystem into seven cross-species functional clusters, uncovering a spatial coupling between microbial lifestyle and metabolic specialization. Applying this framework to a model of host thermal adaptation demonstrated that host resilience was associated with rapid transcriptional activation of key energy-metabolism clusters. Notably, a lineage-specific metabolic shift toward a glycolytic phenotype in Anaerovibrio lipolyticus contributes to a compensatory "nutritional sparing" effect associated with host resilience. This dataset provides a foundational resource for rumen microbial ecology and establishes a technical framework for dissecting phenotypic plasticity within complex microbiomes.
The increase in the incidence of type 2 diabetes mellitus (T2DM) worldwide cannot be attributed solely to genetic and lifestyle factors, underscoring the growing role of environmental metabolic disruptors. Microplastics are increasingly being identified as potential environmental diabetogens, owing to the high risk of human exposure and the potential of microplastics to act as EDC carriers. This review aims to integrate the biochemical and molecular evidence for the association between microplastic exposure and the development of impaired glucose metabolism via endocrine, inflammatory, and metabolic signaling pathways. These microplastics and additives, such as bisphenols, phthalates, and POPs, interact with nuclear hormone receptors, including the estrogen receptor, peroxisome proliferator-activated receptor, and aryl hydrocarbon receptor, resulting in aberrant transcriptional control of genes involved in the regulation of metabolism. Microplastics exposure may cause oxidative stress-mediated activation of stress kinases, inhibition of insulin receptor substrate-1, suppression of PI3K-Akt signaling, GLUT4 translocation, and mitochondrial dysfunction, which together result in systemic insulin resistance. In addition, β-cell damage, systemic inflammation, and changes in the gut microbiome interfere with the regulation of glucose metabolism in the liver, muscle, and adipose tissues.
Antimicrobial resistance (AMR) is a One Health challenge driven by clinical antibiotic use and environmental processes that shape microbial selection and genetic exchanges. Nature-based solutions (NbS), particularly constructed wetlands, are increasingly used to remove complex contaminant mixtures from aquatic systems. Although these systems often achieve considerable efficiencies, their effects on AMR dynamics remain unclear. This review synthesizes evidence on how aquatic rhizospheres function as microbiome-associated ecological reactors, in which contaminant mixtures, redox gradients and microbial interactions jointly influence resistance. We show that wetlands can function along a continuum between antimicrobial resistance attenuation, persistence, and dissemination, depending on the design, operation, and ecological context. Importantly, the removal of bioactive compounds does not necessarily translate to a reduced resistance risk, as selective pressures may persist within biofilms, sediments, and plant-associated compartments. We propose a microbiome-informed conceptual framework for interpreting AMR in nature-based systems. This perspective identifies potentially modifiable leverage points for understanding, interpreting, and potentially mitigating resistance-related risks and underscores the need for monitoring and risk assessment strategies that extend beyond conventional chemical metrics and incorporate the One Health exposure pathways. Together, these insights reposition wetlands as conditional solutions, whose sustainability depends on explicitly addressing antimicrobial resistance, alongside contaminant removal.
The increasing demand for sustainable alternatives to chemical disinfectants in postharvest fruit handling has incentivized exploration into microbiome-based interventions. We evaluated the impact of lactic acid bacteria (LAB)-derived postbiotic formulations (FF1, FF2, FF3) and a commercial disinfectant (CD) on the microbial community structure of the strawberry fruit surface. Taxonomic and functional changes in the microbial communities were evaluated using shotgun metagenomic sequencing, enabling comprehensive profiling of microbial composition and functional potential through gene family abundance, EggNOG functional categories, KEGG pathways, and MetaCyc metabolic reconstruction. The tested formulations consisted of a precipitated peptide-protein extract (PP) from Weissella cibaria UTNGt21O (FF2), used as the antimicrobial agent, and an exopolysaccharide (EPS) from W. confusa UTNCys2-2 (FF3), serving as a biopolymer carrier, applied in combination (FF1: PPGt21O + EPSCys2-2) or individually. Our integrated analysis revealed that the highly suppressive formulation, FF1, outperformed the CD by fundamentally restructuring the microbial landscape. Taxonomically, FF1 notably reduced the abundance of key opportunistic spoilage or hazardous organisms. Rather than acting as an indiscriminate biocide, FF1 functioned as a targeted ecological disruptor. Functional profiling (eggNOG, KEGG, and MetaCyc) suggested potential shifts in functional capacity, including a reduced relative abundance of genes associated with translation machinery, cellular membrane expansion (stearate biosynthesis), and host lipid degradation (fatty acid β-oxidation). In parallel, the FF1-treated microbiome showed a higher relative abundance of genes linked to stress-response functions, including heat shock proteins and cell wall-related processes such as peptidoglycan maturation. In contrast, less restrictive formulations (FF2 and FF3) permitted the proliferation of opportunists such as Pseudomonas spp. and Xanthomonas fragariae, accompanied by active energy-consuming and tissue-degrading metabolic signatures. These findings suggest possible underlying mechanisms of LAB-derived postbiotics, demonstrating that FF1 forces the surface microbiome into a metabolically restricted, non-degradative survival state, potentially contributing to the preservation of postharvest strawberry quality.
To investigate whether secondhand smoke (SHS) exposure alters the ocular surface microbiome (OSM) in children and to explore potential functional consequences. 432 children aged 3-18 years were enrolled, including 111 SHS-exposed and 321 unexposed controls. Conjunctival swabs were collected and analyzed by 16S rRNA gene sequencing targeting the V3-V4 region. Sequencing data were processed with Qiime2 and DADA2, and taxonomic classification was based on the SILVA 138 database. Alpha diversity and beta diversity were compared using t-tests and PERMANOVA. Differentially abundant taxa were identified using LEfSe, and predicted functional pathways were analyzed using PICRUSt2 with MetaCyc and KEGG annotation. SHS-exposed children showed significantly altered alpha diversity (Chao1, Shannon, Simpson) and distinct beta diversity compared with controls. LEfSe analysis revealed enrichment of several phyla and genera, including Lactobacillus and Rubellimicrobium in controls, with no taxa enriched in SHS-exposed children. Functional prediction showed enrichment of metabolism pathways such as L-methionine salvage, biphenyl, heparin, and toluene degradation and immune-related pathways, including complement activation, T and B cell receptor signaling, MAPK, and TGF-beta pathways. SHS exposure in children is associated with significant alterations in ocular surface microbial diversity, community structure, and predicted functional pathways related to environmental stress and immune signaling. These findings highlight the sensitivity of the pediatric OSM to SHS exposure and underscore the importance of minimizing environmental tobacco smoke to protect children's ocular health.
How do some human infants adapt to environmental challenges while others do not? We examined whether infant behavioral responses to maternal unpredictability predict early inhibitory control and are linked to gut microbial community composition and neuroactive metabolic potential. Maternal unpredictability, quantified as the entropy of sensory signal transitions during mother-infant interaction (N = 255; 2-6 months), predicted poorer infant inhibitory control at 19-28 months. However, infants who exhibited high visual orienting behavior (VOB) under high unpredictability showed later inhibitory control comparable to infants exposed to low unpredictability, suggesting an adaptive behavioral buffering strategy. In a subset of infants (n = 87), we tested whether infant age, sex, delivery mode, feeding, maternal education, and maternal unpredictability explained variation in gut microbial community diversity. Only feeding status and VOB were significantly associated with both taxonomic and functional microbial profiles. VOB was associated with taxonomic and functional variation along a Bifidobacterium breve and Bifidobacterium longum axis and enrichment of microbial tryptophan and glutamate synthesis genes. Although feeding groups differed in alpha diversity, VOB was not associated with feeding status, suggesting that feeding is not the primary driver of the observed VOB-microbiome signatures. Interaction models of neuroactive gene functions revealed that microbial signatures vary across combinations of VOB and maternal unpredictability, suggesting that the microbial support for deploying visual attentional strategies differs under distinct levels of environmental unpredictability. Together, these findings support a framework in which infant behavioral strategy is associated with variation in gut microbial composition and metabolic gene potential.
Tomato bacterial wilt, caused by Ralstonia solanacearum, is a globally devastating soil-borne disease that poses a serious threat to the sustainable development of tomato production. Arbuscular mycorrhizal fungi (AMF) are well-recognized beneficial soil microorganisms that significantly promote plant growth, enhance nutrient uptake, and improve resistance to various biotic and abiotic stresses. However, a comprehensive understanding of the potential of AMF to suppress tomato bacterial wilt is still lacking. In this study, we demonstrate that AMF inoculation remarkably reduces the disease index of bacterial wilt in tomato plants, upregulates the expression of pathogenesis-related (PR) genes, and enhances antioxidant enzyme activities, collectively strengthening systemic disease resistance. High-throughput 16 S rRNA gene sequencing revealed that AMF colonization drives substantial reassembly of the rhizosphere microbiome. Notably, AMF colonization promoted the recruitment of beneficial bacterial genera, including Bacillus and Brevibacillus, while significantly suppressing the abundance of Ralstonia. Furthermore, we isolated two Brevibacillus strains, designated AQC211 and AQC296, from the mycorrhizosphere of healthy tomato plants, both exhibited antagonistic activity against R. solanacearum in vitro. Pot experiments confirmed that inoculation with the AQC211 strain significantly reduced the incidence and severity of bacterial wilt. These findings indicate that AMF can not only directly prime plant systemic resistance but also indirectly enhance protection against bacterial wilt by shaping a disease-suppressive rhizosphere microbiome.
The coastal waters of Bangladesh support rich aquatic biodiversity, including the commercially important shrimp Penaeus monodon. However, antimicrobial resistance (AMR) poses a growing threat to aquaculture, ecosystem stability, and human health. In this study, we investigated bacterial AMR profiles and characterized the gut microbiomes of wild (Natural) and cultured P. monodon from the northern Bay of Bengal, Bangladesh. Culture-based and biochemical methods were used to identify bacterial pathogens of shrimp shells, and antimicrobial susceptibility was assessed using the disc diffusion method. Shotgun metagenomic sequencing was used to characterize gut microbial diversity and identify antibiotic resistance genes (ARGs). All Klebsiella isolates were resistant to ampicillin (100%) and showed high resistance to azithromycin (83%) and nitrofurantoin (73%). Pseudomonas isolates were 93.10% resistant to ampicillin, whereas Vibrio isolates had notable resistance to azithromycin (71.05%) and colistin (63.16%). Metagenomic analysis revealed comparable alpha diversity between wild and cultured shrimp, with Vibrio being predominant in both groups and V. parahaemolyticus as the most abundant species. Cultured shrimp harbored greater microbial diversity, including additional genera such as Shewanella, Lactococcus, and Enterobacter. A total of 30 ARGs were detected, primarily associated with β-lactams and tetracycline resistance. Cultured shrimp exhibited a broader ARG spectrum, reflecting potential anthropogenic impacts on aquaculture practices. These findings suggest that cultured shrimp environments can serve as reservoirs of resistant bacteria and ARGs. Therefore, improved antimicrobial stewardship and regular monitoring are essential to curb the spread of AMRs in marine ecosystems.
Environmental pollution resulting from heavy metals constitutes a critical global issue. Remediation technologies offer potential solutions, particularly through the innovative use of endophytic microbes, either independently or in conjunction with plants. This solution is based on the ability of certain endophytic bacteria to produce metallophores, which are low-molecular-weight compounds capable of chelating various heavy metals. This study investigates ten bacterial endophytes isolated from the medicinal plant Galium aparine L. belonging to the Bacillus, Priestia, and Peribacillus genera. We tested different media to efficiently induce their production and assessed their ability to chelate various heavy metals, including highly toxic Pb2+, Cd2+ and Hg2+. Moreover, we examined in detail of their metallophore gene clusters, their organization, diversity and prevalence, by broad homology search. All strains exhibited moderate to high metallophore production ability, with few strains capable of chelating more metals than iron. Among them, Priestia sp. GS2 was identified as promising producer, reaching up to 60% SU, with binding activity also towards Co2+, Mn2+, Zn2+, Ni2+ or Cu2+. Also, Peribacillus frigoritolerans GR2 exhibits a remarkable ability to chelate Pb2+, Hg2+ and Cd2+. An in-depth analysis of the biosynthetic gene clusters and enzymes involved in metallophore biosynthesis revealed homologous clusters within previously deposited genomes, highlighting their distribution and potential evolutionary conservation. The strains demonstrated capacity for metallophore production and heavy metal chelation, which makes them promising candidates for the development of advanced microbial solutions. A genome-guided selection approach can guide the selection of strains for agricultural applications, where they enhance plant nutrient uptake, suppress soil pathogens, and support sustainable fertilization strategies beyond sequestering crucial metals. Apart from agriculture, purified metallophores can aid bioremediation and mobilization of heavy metals from various environments and matrices.
We report the 16S rRNA gene (V3-V4) amplicon dataset of microbial communities from outdoor air filters at three traffic-exposed locations in the Klang Valley, Malaysia. This baseline characterization of the tropical atmospheric microbiome contributes to understanding airborne microbial diversity in Southeast Asian urban environments.
Silkworm (Bombyx mori) excrement accumulates in large quantities and causes severe environmental pollution, with highly crystalline cellulose limiting efficient resource utilization. The development of effective cellulose-degrading bacterial technologies is crucial for advancing biotechnological applications. This study investigated the effects of exogenous microbial agents and housefly larvae composting on cellulose biodegradation in silkworm excrement. After six days, the cellulose content decreased by 52.6%, 58.2%, and 64.0% in the treatment groups, respectively, which was significantly greater than the 39.41% reduction in the control group without exogenous agents. The combination of exogenous microbial agents and housefly larvae reshaped the bacterial community, increasing the relative abundance of cellulose-degrading taxa. Specifically, Firmicutes and Actinobacteria were enriched, and the abundances of Bacillus, Pseudomonas, and Cellulosimicrobium increased. Functional predictions via PICRUSt indicated that carbohydrate metabolism was predicted to dominate bacterial activity, while Tax4Fun analysis suggested that exogenous agents were associated with increased predicted abundances of endo-β-1,4-glucanase and exo-β-1,4-glucanase genes in excrement, which may relate to accelerated cellulose degradation. This study suggests that the combination of exogenous microbial agents and housefly larvae could promote cellulose-degrading bacterial populations and the genetic potential for cellulase activity, representing a possible strategy for silkworm excrement bioconversion.
Living entities, inlcuding laboratory animals, are composed of the host and its associated microbial communities and defined as holobionts. The host genotype and its microbiome drive together as a metagenome, the holobiont phenotype, with the microbiome itself as a well-recognized source of phenotypic variation. Multiple environmental (diet, light/dark cycles, etc.) as well as host-related factors (genotype, maternal effect, etc.) not only influence the animal experimental phenotype but also contribute to the shaping of the microbiome, raising the question of whether the microbiome of experimental animals represents an extrinsic, intrinsic, or intermediate influence. Currently, there is sufficient evidence that microbial communities at different body sites are shaped by distinct endogenous and exogenous factors, indicating that the host does not leave its microbial status to chance but instead actively modulates it through host-specific mechanisms, despite extrinsic influences. This leads to a microbiome that reflects a 'fingerprint' of its own endogenous and exogenous influences. This suggests that the microbiome of experimental animals is an intermediate factor with both intrinsic and extrinsic components and underscores the importance of refining the selection of the appropriate metagenome for each specific rodent experiment.
Cryospheric ecosystems in the high Arctic harbor largely unexplored microbiomes with significant biotechnological potential. The present study evaluates the biohydrogen production capabilities of the indigenous microbiome of Ny-Ålesund, Svalbard, using glacial ice and surface water samples. Dark fermentation batch assays were performed at 4 °C and 20 °C with 2-bromoethanesulfonate (BES), a methanogenic inhibitor, to track the succession of metabolic and taxonomic diversity. Metagenomic and functional analyses revealed that under 20 °C and BES conditions, psychrotolerant microbial communities maximize biohydrogen production to 85% of the total biogas produced, with an acetate-dominant fermentation pathway, as inferred from volatile fatty acid (VFA) analysis. This evolves into a highly coordinated system utilizing a coupled Rnf-nitrogenase route alongside Formate Hydrogenlyase and [FeFe]-hydrogenase pathways. Kinetic modelling using the Modified Gompertz equation, along with Q10 temperature-sensitivity indices, demonstrated a very high latent catalytic potential in these cold-adapted microbiomes. This study indicates that Arctic microbiomes are highly elastic thermodynamically and could serve as highly efficient, manipulatable biocatalysts for the environmental recovery of bioenergy through engineered low-temperature systems.
Cobalamin (vitamin B₁₂) is synthesized only by certain bacteria and archaea and is rarely found in plant-derived foods because plants neither synthesize nor require this cofactor. The edible duckweed Wolffia globosa Mankai is unusual in containing bioavailable cobalamin, suggesting a microbial origin. However, how cobalamin biosynthetic capacity is organized within angiosperm-associated microbiomes remains largely unresolved. Here, we investigated bacterial community structure and cobamide biosynthetic potential across the cultivation medium, plant surface, and internal tissues of Mankai to determine how cobalamin production is maintained in this aquatic plant microbiome. Bacterial communities differed significantly among compartments, with the endosphere forming a low-diversity, host-filtered microbiome enriched in specialized taxa. Genome-resolved metagenomics showed that only a minority of endophytic bacteria encoded near-complete cobamide biosynthesis pathways consistent with de novo synthesis. In contrast, many co-occurring taxa lacked multiple biosynthetic steps but were enriched in genes associated with cobamide precursor salvage and remodeling. Network analysis identified putative producer taxa as highly connected hubs linked to salvager populations, consistent with metabolite cross-feeding. Comparative genomic analysis demonstrated reduced cobamide biosynthetic gene complements in endophytic genomes relative to closely related free-living strains, supporting adaptive pathway reduction in the host-associated niche. Cobalamin production in the Mankai endosphere appears to arise from a metabolically interdependent bacterial consortium rather than from single autonomous producers. These findings identify cooperative micronutrient biosynthesis as an organizing principle in plant-associated microbiomes and position Mankai as a tractable model for studying cobamide-mediated microbial cooperation in aquatic crops. Understanding these interactions may support microbiome-informed strategies to stabilize micronutrient production and functional resilience in controlled aquatic plant cultivation systems.
The human gut microbiome represents a dynamic microbial ecosystem profoundly influencing host physiology, immune development, and disease susceptibility. While metagenomic approaches have advanced our understanding of microbial composition and functional potential, they remain insufficient to capture the real-time molecular events governing host‒microbe interactions. Taxonomic abundance and genomic content alone do not reflect active gene expression or phenotypic output, and functional roles cannot be reliably inferred from phylogenetic identity, given the substantial heterogeneity observed even within species. Central to bridging this gap is the concept of bacterial functional plasticity, with a focus on phase-mediated functional plasticity, the intrinsic capacity of microbes to rapidly remodel their activity and phenotype in response to environmental and host-derived cues. This review highlights phase variation as a prominent and evolutionarily conserved mechanism underlying plasticity, encompassing DNA inversions, short-sequence repeat modifications, and broader structural genomic variation. Emerging evidence demonstrates not only the prevalence of phase-variable mechanisms across diverse gut taxa but also their significant regulatory, ecological, and immunological consequences. These findings reframe the microbiome from a static consortium of species to a functionally dynamic system capable of rapid rewiring in response to environmental pressures. By integrating genomic, ecological, and host-response data, this review lays the groundwork for mechanistic frameworks that could explain how flexible microbial strategies influence bacterial behavior and host outcomes. Moving beyond cataloging microbial composition toward deciphering the logic of functional adaptation will be essential for translating microbiome research into predictive, diagnostic, and therapeutic applications.
The oral microbiome has been shown to be associated with respiratory health, primarily in adult case studies or among children. This relationship has been scarcely investigated in adult population-based cohorts. To investigate the association between oral microbiome and respiratory health, more specifically asthma, chronic rhinosinusitis (CRS), lung function and fractional exhaled nitric oxide (FeNO) in a population-based cross-continental multicentre study among adults. Subgingival samples from 355 adult European Community Respiratory Health Survey participants from Norway, Australia and Estonia underwent metagenomic sequencing. Respiratory disease was defined from questionnaires and sensitisation from specific immunoglobulin E (IgE)/skin prick tests. Spirometry and FeNO were measured. The associations between alpha diversity and disease status were evaluated in cross-sectional analyses using logistic regression adjusting for sex, smoking and study centre. Differential abundance analyses were performed using analysis of compositions of microbiomes with bias correction. Alpha diversity differed by study centre and sensitisation status and was associated with non-allergic CRS (richness: 1.12, 95% CI 1.03 to 1.22). A similar though not statistically significant pattern was seen for forced vital capacity (FVC) below the lower limit of normal (LLN). Lachnospiraceae and Xanthomonas were more abundant in the oral microbiome of non-asthmatics and individuals without CRS, respectively, as compared with asthmatics and CRS patients. Several functional genes (1477-3391) and genera (54-98) were only present in the non-case groups, whereas individuals with affected respiratory health had 0-74 unique functional genes, but no unique genera present only in their respective groups. Increased alpha diversity was associated with non-allergic CRS and a similar trend was seen for FVC below LLN. Bacterial composition and functional profiles of the oral microbiome differed by respiratory health status. This study is novel in exploring functional gene profiling in relation to asthma and FeNO.
The gut microbiota plays a critical role in mammalian health, yet remains poorly understood in wild Asian elephants (Elephas maximus). This study characterized the gut microbiome of wild elephants using 16S rRNA sequencing of fecal samples collected from five natural habitats in Thailand: Doi Pha Mueang Wildlife Sanctuary (DPM), Khao Ang Rue Nai Wildlife Sanctuary (KARN), Khao Yai National Park (KY), Phuluang Wildlife Sanctuary (PL), and Sublangka Wildlife Sanctuary (SLK), representing distinct geographic regions. Across all sites, Thai wild elephants shared a core gut microbiota dominated by fiber-degrading bacteria. Firmicutes was the most abundant phylum, followed by Bacteroidota, Actinobacteriota, and Proteobacteria. At the family level, Lachnospiraceae predominated, followed by Oscillospiraceae, Anaerovoracaceae, and Christensenellaceae. Environmental variable, including geographic coordinates and minimum elevation, significantly influenced microbial community composition and explained patterns of beta diversity, indicating distinct gut microbiota profiles among elephant populations from different forest regions. These findings establish baseline gut microbiome data for wild Asian elephants and provide a foundation for future ecological and conservation-focused microbiome studies.
Extreme environments such as acid mine drainage (AMD) host highly specialized microbial communities that drive profound biogeochemical cycles. Within these ecosystems, iron- and sulfur-metabolizing taxa catalyze mineral weathering, generating intense acidity and mobilizing heavy metals. However, more than 97% of these microorganisms remain uncultured "microbial dark matter," heavily restricting our understanding of extremophile metabolism and adaptation. Here we present the Microbial Biobank of AMD (mbAMD), a culturomics-derived collection of 652 isolates spanning 42 species-including 21 novel taxa-that achieves 86.7% coverage of the global AMD core microbiome. Functional validation demonstrates that 36 of these taxa possess active iron or sulfur metabolic capacities, including the discovery of the first pure cultures of acid-tolerant sulfate reducers. Comparative genomic analyses across these isolates reveal that extreme environmental adaptation is predominantly driven by pervasive horizontal gene transfer. Specifically, extremophiles preferentially acquire adaptive genes governing acid tolerance and metal resistance from phylogenetically proximal relatives rather than distant donors. These findings elucidate the modular evolutionary strategies of extremophiles and provide critical functional resources for advancing biohydrometallurgy and environmental bioremediation. This mbAMD resource will accelerate biohydrometallurgical process optimization and environmental bioremediation strategies while advancing evolutionary microbial ecology research.