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Genome-Resolved Functional Profiling of Osteoporosis-Associated Gut Bacteria Highlights Putative Metabolic and Immunogenic Signatures of the Gut-Bone Axis.

The gut microbiota has emerged as a potential regulator of bone metabolism, but the genome-encoded functional repertoire of osteoporosis-associated gut bacteria remains insufficiently characterized. This study performed in silico functional profiling of gut bacterial taxa associated with osteoporosis, low bone mineral density, or comparator bone-related phenotypes. Twenty candidate taxa were selected from evidence in the human microbiome and represented by 26 curated bacterial reference genomes. Genome-wide annotations were used to map predicted gut-bone axis signatures, carbohydrate-active enzyme (CAZyme) repertoires, selected Kyoto Encyclopedia of Genes and Genomes pathways, and gutSMASH-predicted metabolic gene clusters. Functional burdens were normalized as hits per 1000 annotated proteins and integrated into metabolic, immunogenic, CAZyme, KEGG, and metabolic gene cluster profiles. Twelve predicted gut-bone axis signatures were identified, comprising 3337 primary candidate protein hits and a strict high-confidence subset of 2497 hits. Dominant signatures included vitamin B12/cobalamin metabolism, folate/one-carbon metabolism, peptidoglycan/cell-wall biosynthesis, and short-chain fatty acid-related functions. Dialister invisus, Dialister succinatiphilus, Megamonas funiformis, and Megamonas hypermegale showed the strongest normalized predicted gut-bone axis signal. These hypothesis-generating findings prioritize microbial metabolic and immunogenic features for future metagenomic, metabolomic, and experimental validation studies.

Osteoporosis

Assessing the diversity and functional profile of the "microbial proteome" in fermented foods.

Fermented foods are staples in diets worldwide and are known for their health benefits. Microorganisms are the key to fermented food production as they convert raw substrates into digestible, nutritious, and health-promoting products. While microbes are essential for fermented food production, their contribution to the dietary protein profile of the final food product in terms of microbial biomass is largely unknown. We analyzed proteins from 17 fermented foods using metaproteomics to identify and quantify microbial and food-derived proteins. We found that microbial proteins contribute up to 11% of the total protein content in fermented foods and comprise as much as 60% of the total number of identified proteins. These microbial proteins included many for central functions in microbial cells, such as glycolysis enzymes, translation machinery, and chaperones, as well as proteins for specialized functions that are important for the ecological niches in food fermentation, such as carbohydrate degrading enzymes and proteases. Some of these microbial proteins, such as proteases, could impact gut physiology. These findings highlight the substantial contribution of microbial proteins to the nutritional and functional profile of fermented foods, which may have important implications for interactions with the gut microbiota and health outcomes.

Fermented Foods

Venomics of the Arabian saw-scaled viper (Echis coloratus) through transcriptome-guided proteomics and in vitro functional profiling.

The Arabian saw-scaled viper (Echis coloratus) is among the snakes of highest medical relevance in the Middle East and North Africa. However, to date, its venom has been investigated in a very limited number of studies, and much remains unknown regarding its compositional and functional properties. By integrating proteotranscriptomics with bioactivity profiling, we present a comprehensive transcriptome-level catalogue of E. coloratus venom components and their associated biological activities. Our analysis identified 183 venom components belonging to 17 distinct protein families. Relative toxin abundances revealed that 92% of the venom proteome is composed of C-type lectin and C-type lectin-related protein (CTL), L-amino acid oxidase (LAAO), phospholipase A2 (PLA2), snake venom serine protease (SVSP), and snake venom metalloproteinase (SVMP), with CTL and PLA2 alone accounting for 73% of the total composition. Bioassays targeting key aspects of viperid envenomation demonstrated potent protease and PLA2 activity in a concentration-dependent manner. In contrast, Factor Xa-like, plasmin-like, and haemolytic activities were negligible. Marked cytotoxicity was observed at the highest concentration tested (i.e., 25 μg/ml) in the mammalian cell lines MDCK II and Calu-3, whereas cytotoxic effects were minimal at lower concentrations. These findings highlight the complexity and potency of E. coloratus venom, and provide a valuable foundation for improving our understanding of envenomation caused by this species.

Animals

Distinct cell morphotypes of Aureobasidium melanogenum ZN exhibit differential functional profiles in promoting maize growth.

Black yeast-like fungi of the genus Aureobasidium exhibit morphological plasticity, but whether distinct cellular states within the same genetic background are associated with different plant growth-promoting functions remains unclear. Here, yeast-like cells (YL), swollen cells (SC), and chlamydospores (CH) of Aureobasidium melanogenum ZN were characterized. YL was associated mainly with siderophore production and laccase activity, SC with extracellular polysaccharide accumulation, and CH with phosphate mobilization and higher ammonia and IAA production. Whole-genome and comparative genomic analyses revealed a shared repertoire related to nutrient acquisition, auxin-associated metabolism, extracellular oxidation, and carbohydrate remodeling, with expansions in nutrient- and cell-surface-related gene families. Transcriptomic and metabolomic analyses showed distinct deployment of these capacities, with CH exhibiting broad reprogramming of tryptophan-associated, nitrogen, phosphate, central-carbon, and amino-acid metabolism. In maize, CH at the optimal inoculation concentration of 105 CFU·mL-1 produced the strongest growth promotion, increasing plant height, dry biomass, root length, root surface area, and root volume by 58.6%, 365.1%, 191.0%, 194.3%, and 222.4%, respectively. Consistent with this pronounced growth phenotype, maize root transcriptomics showed coordinated CH-induced responses involving root development, nutrient transport, redox regulation, and root-interface remodeling. Root-zone tracking showed greater short-term stability and persistence of CH. These findings identify cellular state as an important functional dimension of Aureobasidium-plant interactions and provide a basis for developing fungal inoculants with defined beneficial cellular states.

Zea mays

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

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

Antibiotic resistance genes

Genome-resolved analysis of colonization factor repertoires reveals ecological stratification in cervid gut microbiomes.

INTRODUCTION: Colonization factors (CFs) are important microbial traits associated with persistence and host adaptation in the gut, yet their large-scale organization in cervid gut microbiomes remains unclear. METHODS: A total of 3,311 non-redundant high-quality metagenome-assembled genomes (MAGs), derived from 688 cervid gut metagenomic samples across 15 publicly available projects and one in-house dataset, were analyzed. CF-associated genes were identified by comparison against the GHA CF database, and CF repertoires were characterized at genome, host-species, and gastrointestinal-segment levels. RESULTS: A total of 138,729 CF-associated genes spanning 71 CF families were identified. MAGs from Cervinae contained richer CF repertoires than those from Caprinae, and CF47 (Peptidase_C69), CF24_29 (QueH), and CF18 (Glycos_transf_2) were among the most prevalent families. CF repertoires were strongly structured by taxonomy, showed a moderate association with bacterial phylogenetic distance, and formed two recurrent genome-level configurations with distinct KEGG functional profiles. Integration of sample metadata further revealed differentiation of CF repertoires across host species and gastrointestinal segments, representing the major ecological dimensions examined in this study. Segment-associated CF variation was accompanied by redistribution of broader functional profiles, including enrichment of carbohydrate and lipid metabolism in the jejunum, membrane transport in the ileum, xenobiotics biodegradation in the cecum, and environmental adaptation in the rumen. DISCUSSION: These findings provide a genome-resolved view of CF repertoire organization in cervid gut microbiomes and demonstrate that colonization-associated functions are structured across microbial lineages and ecological contexts. This study highlights the importance of considering microbial taxonomy and host-associated environments when interpreting the distribution of CF repertoires in mammalian gut ecosystems.

Cervidae

Cross-species phenotypic profiling uncovers functional determinants of bacterial cold shock adaptation.

Temperature shifts impose broad physiological stress, requiring precise and dynamic regulatory programs to restore cellular homeostasis. While the heat shock response is well characterized, the mechanisms underlying cold shock response (CSR) remain less understood. To identify genes critical for cold adaptation, we applied transposon sequencing (Tn-seq) to monitor mutant fitness across the full course of CSR and sustained low-temperature growth in two mesophilic bacteria, Escherichia coli and Bacillus subtilis. In B. subtilis, phenotypic profiling revealed a temporally structured program: membrane fluidity and cell wall remodeling were most critical in the early stage of CSR, whereas post-transcriptional regulation became essential during late-stage recovery to reprogram gene expression and restore growth. Cross-species comparison uncovered both conserved and species-specific mechanisms, with RNA metabolism and ribosome/translation regulators playing broad roles. Specifically, we identified a conserved synergy between two ribosomal RNA methyltransferases, RsmA and RsmH, in promoting cold adaptation. In B. subtilis, mutants lacking these enzymes exhibited significant delay in translation recovery following cold-induced global inhibition. Together, these findings provide a comparative, systems-level view of bacterial cold adaptation and establish a framework for exploring stress responses in pathogens and extremophiles.

Cell envelope

Dietary Polyphenol Acteoside-Related Molecular Signatures in Clear Cell Renal Cell Carcinoma: Multi-Omics Profiling and Functional Validation of IMPDH1.

Clear cell renal cell carcinoma (ccRCC) is characterized by substantial metabolic and molecular heterogeneity, but the disease-relevant programs associated with acteoside, a dietary polyphenol, remain poorly understood. We integrated predicted acteoside targets with bulk, single-cell, and spatial transcriptomic data from ccRCC and combined molecular subtyping with cross-cohort machine-learning analysis. Acteoside-related signatures were preferentially enriched in malignant compartments and increased with tumor grade and stage. Consensus clustering identified two molecular subtypes with distinct biological and clinical features. C1 was associated with immune activation, metabolic activity, and more favorable survival, whereas C2 showed greater genomic instability, reduced renal epithelial differentiation, and poorer outcomes. We further benchmarked multiple machine-learning strategies and established a 10-gene prognostic model that retained predictive performance across independent cohorts, with IMPDH1 emerging as the strongest risk-associated feature. Functional experiments confirmed the biological relevance of IMPDH1: its knockdown suppressed ccRCC cell proliferation, DNA synthesis, colony formation, and migration, whereas overexpression produced the opposite effects. Together, these findings indicate that acteoside-related molecular signatures capture clinically relevant heterogeneity in ccRCC and provide a framework for linking dietary-polyphenol-related molecular space with tumor biology. The identification and functional validation of IMPDH1 further highlight its potential importance in ccRCC progression.

IMPDH1

Metabolic reprogramming and taxonomic drivers in bacterial vaginosis: A large-scale metagenomic meta-analysis.

OBJECTIVE: Bacterial vaginosis (BV) represents a profound ecological shift from a Lactobacillus-dominated microbiota to a diverse polymicrobial biofilm associated with adverse outcomes. While taxonomic signatures are well-documented, the functional mechanisms driving this transition remain obscured. This study elucidates the genomic potential for metabolic reprogramming and the putative "functional handover" underpinning the stability of the dysbiotic state. METHODS: A computational meta-analysis of 3557 vaginal microbiomes from diverse global cohorts was performed using the standardized MGnify pipeline. A high-resolution subset of 187 whole-genome shotgun (WGS) metagenomes was stratified to compare functional potential across demographic groups. Taxon-function interaction networks were constructed, utilizing a dual-filter statistical approach (p&#x202f;<&#x202f;0.05 and effect size ranking), to map the shift from homeostatic maintenance to dysbiotic metabolic potential. RESULTS: BV was characterized by a fundamental shift from "maintenance" pathways to high-turnover "growth-oriented" genomic repertoires. While ABC transporter-like domains were present in healthy communities, dysbiosis was marked by a quantitative expansion and diversification of these systems alongside P-loop NTPases. Network analysis revealed a putative "functional handover": while Gardnerella serves as the adherent structural scaffold, the metabolic burden appears to be associated with secondary anaerobes, specifically BVAB1 and Sneathia, which exhibit strong genomic correlations with nutrient transport and stress response pathways. Crucially, microbiomes from women of African ancestry (Black cohort) exhibited a distinct functional profile with genomic signatures consistent with functions previously associated with resistome expansion (e.g., tetracycline/macrolide resistance), contrasting with Asian cohorts. CONCLUSION: BV is a state of metabolic reprogramming where genomic functional dominance is transferred from Lactobacillus to a cooperative network of anaerobic opportunists. Identifying BVAB1 and Sneathia as candidate metabolic engines, supported by a Gardnerella scaffold, challenges current therapeutic paradigms and highlights the potential for precision medicine targeting specific functional drivers and resistome profiles across diverse populations.

Humans

Imaging-Guided Omics Technologies for Resolving Rare Cancer States and Advancing Nanomedicine.

The ability to resolve rare and transient cellular states is critical for understanding metastasis, immune evasion, and therapy resistance in cancer, yet these dynamic processes often escape detection by conventional sequencing and imaging approaches. Recent advances at the interface of nanotechnology, high-resolution live-cell imaging, and single-cell/spatial multiomics methods have enabled functional profiling of cells with unprecedented precision within their native microenvironment. In this Mini-Review, we highlight emerging nanoscale platforms that couple real-time phenotypic imaging with molecular readouts, such as FUNseq and CIN-seq, to directly link functional heterogeneity to transcriptomic, proteomic, and epigenomic information. By integrating nanoscale optical imaging, microengineered perturbation tools, and AI-driven computational analysis, these technologies open up new avenues for dissecting rare metastatic, therapy-resistant, or immune-evasive subpopulations. We further discuss how these next-generation imaging-guided single-cell and spatial omics platforms not only advance fundamental cancer biology but also create opportunities to accelerate the development of nanomedicine applications.

Humans

Host-independent metagenomics reveal gut bacteria contribution to Delia antiqua growth by vitamin B6 provision.

Insect guts host a diverse and abundant array of microorganisms. These microbes improve host fitness by extensively involving in a range of crucial physiological processes, which have mainly been revealed by high-throughput sequencing, particularly metagenomics. However, it is almost impossible to make an accurate and complete distinction between the genetic functions of microbial symbionts and insect hosts without host genome data. By comparing metagenomic data from gut germ-free and nonaxenic larvae, we accurately identified the data belonging to the gut microbiome of the onion maggot Delia antiqua (Diptera: Anthomyiidae). Besides, a correlation between bacteria of the genus Wohlfahrtiimonas (Gammaproteobacteria: Pseudomonadaceae) and vitamin B6 metabolism was detected through collinearity analysis. Furthermore, in vitro tests confirmed that the gut bacterium Wohlfahrtiimonas larvae contributed to the growth of D. antiqua larvae via the independent synthesis of vitamin B6. This study provides a comprehensive view of the gut bacterial diversity in D. antiqua and reveals a functional profile that is strictly specific to the gut microbiota of this species. It has preliminarily revealed the functional differentiation between insect hosts and their symbiotic microorganisms. This study also offers a technical reference for the study of microbial symbiotic functions in other insect-microbe symbioses without host genomic data.

Animals

Comparative characterization of six teleost piscidins reveals distinct antimicrobial, antibiofilm and stability profiles.

Piscidins are cationic &#x3b1;-helical antimicrobial peptides (AMPs) that constitute a key component of the innate immune defense of teleost fish, yet the relationship between their genomic organization, structural properties, and functional specialization remains incompletely understood. In this study, six piscidin peptides from Epinephelus akaara, Seriola dumerili, Thunnus maccoyii, Argyrosomus regius, Dicentrarchus labrax, and Epinephelus coioides were characterized through an integrated sequence-to-function approach combining comparative genomics, structural modeling, physicochemical analysis, and in vitro validation, with the aim of identifying candidates with potential for biomedical and biotechnological applications. All genes studied exhibited the conserved four-exon, three-intron architecture characteristic of teleost piscidins. Structural modeling and circular dichroism confirmed &#x3b1;-helical conformations under membrane-mimetic conditions, despite measurable differences in hydrophobicity, charge distribution, and predicted membrane insertion parameters. Antimicrobial assays revealed distinct functional profiles: Sd_FI25 and Epinecidin_1 displayed broad antibacterial activity against Gram-positive and Gram-negative pathogens, whereas Dl_FI22 showed selective activity with reduced temporal persistence associated with lower peptide stability. Ea_FF25 exhibited comparatively weak antibacterial potency. Antibiofilm activity varied among peptides and did not uniformly parallel planktonic MIC values. Computational predictions further suggested antiviral and antitumoral potential for several sequences, extending their prospective relevance beyond classical antibacterial roles. Conserved genomic architecture and &#x3b1;-helical structure coexist with pronounced functional diversification among teleost piscidins. These findings demonstrate that integrating structural prediction with experimental validation is an effective strategy for identifying fish-derived innate immune peptides as candidates for biomedical applications.

Antimicrobial activity

Evaluation of linear profile scans; mathematical treatment of line-spread functions.

The profile measurement capability of a scanning multidetector whole-body counter is described using line spread functions. Measurements in air and water phantoms, as a function of energy, are discussed in relationship to the relevant physical processes. A computer program for evaluating bodyprofile scans and an attempt to improve the resolution are reported.

Evaluation Studies as Topic

Genome-wide identification and expression profiling of the MADS-box gene family in Lavandula angustifolia.

BACKGROUND: MADS-box&#xa0;genes encode transcription factors critical for plant development, particularly floral organogenesis, flowering time regulation, and adaptation to environmental stresses. Among these, the MIKCC-type genes are pivotal regulators in floral developmental processes. Although the evolutionary diversification and functional dynamics of MADS-box genes have been extensively characterized in model plants such as Arabidopsis thaliana and Oryza sativa, their evolutionary relationships and functional profiles in Lavandula angustifolia, an economically significant aromatic plant, remain poorly understood. RESULTS: Genome-wide analysis identified 173 MADS-box genes in L. angustifolia, categorized into type I (M&#x3b1;: 26; M&#x3b2;: 0; M&#x3b3;: 10) and type II (MIKCC: 125; MIKC*: 12) based on phylogenetic comparisons with A. thaliana. The MIKCC subgroup was further subdivided into 12 subclasses, including genes central to the ABCDE model of floral organ specification. Structural analyses revealed distinct conserved motifs and exon-intron configurations specific to each subgroup, indicative of functional divergence. Synteny analysis demonstrated Whole Genome Duplication (WGD) and segmental duplications as major contributors to MIKCC gene family expansion, notably among genes linked to floral organ development. Expression profiling via RNA-seq and quantitative real-time PCR (qPCR) showed type II MADS-box genes exhibited higher expression levels with pronounced tissue-specific and developmental stage-specific expression patterns compared to type I genes. Many type II genes displayed significant associations with floral organogenesis, floral transition, and abiotic stress responses, underscoring their essential roles in reproductive development and environmental adaptability in L. angustifolia. CONCLUSIONS: The identification and comprehensive characterization of 173 MADS-box genes in L. angustifolia highlight the significant expansion of the MIKCC subgroup driven primarily by WGD and segmental duplications. The distinct structural features and specific expression patterns observed provide insights into the functional divergence and complexity of these genes, particularly regarding floral organogenesis and adaptation to environmental stress. This study establishes a robust molecular basis for further functional analysis and genetic improvement of aromatic plants.

MADS Domain Proteins

Effects of Fecal Microbiota Transplantation on Intestinal Microbial Characteristics and Clinical Phenotypes in Patients with Parkinson's Disease.

Alterations in the gut microbiota have been associated with Parkinson's disease (PD), but longitudinal microbial changes after fecal microbiota transplantation (FMT) and their clinical associations remain poorly understood. This single-center retrospective observational study included 6 patients with PD, stratified into high- and low-severity subgroups based on disease duration (>6 years vs &#x2264;6 years). Thirty-six fecal samples were collected before FMT and monthly for five months afterward. Microbial diversity, community structure, taxonomic composition, and predicted functional profiles were assessed using 16S ribosomal RNA gene sequencing. Analyses included alpha and beta diversity, taxonomic abundance, linear discriminant analysis effect size, Tax4Fun2-based functional prediction, and Spearman rank correlations between microbial features and clinical indicators. Descriptive analyses indicated differences in microbial richness, diversity, community structure, and predicted functions between severity subgroups and across post-FMT time points. At baseline, the low-severity subgroup had greater microbial richness and diversity than the high-severity subgroup, with relatively higher abundances of taxa including Bifidobacterium and Lactobacillus. One month after FMT, richness and diversity increased from baseline in the high-severity subgroup, accompanied by changes in taxonomic composition. Both subgroups showed time-associated variation in microbial diversity and predicted Kyoto Encyclopedia of Genes and Genomes pathway enrichment after FMT. Predicted functions included carbohydrate and amino acid metabolism, secondary metabolite biosynthesis, membrane transport, and signal transduction. Several operational taxonomic units correlated with indicators of motor impairment, constipation, sleep quality, functional status, and neuropsychiatric symptoms. FMT was therefore associated with longitudinal changes in gut microbial diversity, composition, and predicted functions, and specific microbial features were associated with motor and non-motor indicators. Given the small retrospective cohort, these findings are preliminary and warrant confirmation in larger controlled studies. Future studies should determine whether these microbial alterations are reproducible, persist beyond five months, reflect donor engraftment, and correspond to measurable clinical improvement after transplantation in PD.

Humans

ScGOclust: leveraging gene ontology to find functionally analogous cell types between distant species.

MOTIVATION: Basic biological processes are shared across animal species, yet their cellular mechanisms are profoundly diverse. Comparing cell-type gene expression between species reveals conserved and divergent cellular functions. However, as phylogenetic distance increases, gene-based comparisons become less informative. The gene ontology (GO) knowledgebase offers a solution by serving as the most comprehensive resource of gene functions across a vast diversity of species, providing a bridge for distant species comparisons. RESULTS: Here, we present scGOclust, a computational tool that constructs de novo cellular functional profiles using GO terms, facilitating systematic and robust comparisons within and across species. We applied scGOclust to analyse and compare the heart, gut, and kidney between mouse and fly, and whole-body data from Caenorhabditis elegans and Hydra vulgaris. We show that scGOclust effectively recapitulates the function spectrum of different cell types, characterizes functional similarities between homologous cell types, and reveals functional convergence between unrelated cell types. Additionally, we identified subpopulations within the fly crop that show circadian rhythm-regulated secretory properties and hypothesize an analogy between fly principal cells from different segments and distinct mouse kidney tubules. We envision scGOclust as an effective tool for uncovering functionally analogous cell types or organs across distant species, offering fresh perspectives on evolutionary and functional biology. AVAILABILITY AND IMPLEMENTATION: ScGOclust is publicly available on CRAN: https://cran.r-project.org/web/packages/scGOclust/index.html and development versions are available on GitHub: github.com/Papatheodorou-Group/scGOclust/.

Animals

Evaluation of the gastric microbiota based on body mass index using 16S rRNA gene sequencing.

INTRODUCTION: Obesity is a multifactorial condition influenced by various factors, including the gut microbiota. However, the relationship between the gastric microbiota and obesity remains poorly understood. This study aimed to investigate the composition of gastric microbiota, excluding Helicobacter pylori, in relation to body mass index (BMI) and metabolic indicators. METHODS: Thirty participants undergoing health checkups were classified into three groups-normal weight (BMI 18.5-22.9), overweight (BMI 23.0-24.9), and obese (BMI &#x2265;25.0)-with ten individuals per group. Those with H. pylori infection, atrophic gastritis, or intestinal metaplasia were excluded. Gastric microbiota from four antral biopsies per subject were analyzed using 16S rRNA sequencing and functional profiling by metagenomic prediction. RESULTS AND DISCUSSION: Alpha diversity (Gini-Simpson index) was significantly lower in the combined overweight/obese group than that in the normal group (P=0.049). Beta diversity analysis revealed clear group separation (Bray-Curtis, P=0.005; unweighted UniFrac, P=0.004). Significant species differences between the groups were observed; specifically, the abundances of Muribaculum gordoncarteri, Turicibacter bilis, and Duncaniella dubosii, were significantly reduced in the overweight/obese group. Functional predictions showed differential enrichment of pathways related to fatty acid, amino acid, vitamin, and carbohydrate metabolism across BMI categories. These findings suggest that alterations in the gastric microbiota may be linked to obesity and metabolic dysregulation.

Humans