Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “bacterial functional genomics”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed2024

The promise of CRISPR-associated transposons for bacterial functional genomics.

CRISPR-associated transposons (CASTs) are naturally occurring amalgamations of CRISPR-Cas machinery and Tn7-like transposons that direct site-specific integration of transposon DNA via programmable guide RNAs. Although the mechanisms of CAST-based transposition have been well studied at the molecular and structural level, CASTs have yet to be broadly applied to bacterial genome engineering and systematic gene phenotyping (i.e. functional genomics) - likely due to their relatively recent discovery. Here, we describe the function and applications of CASTs, focusing on well-characterized systems, including the type I-F CAST from Vibrio cholerae (VcCAST) and type V-K CAST from Scytonema hofmanni (ShCAST). Further, we discuss the potentially transformative impact of targeted transposition on bacterial functional genomics by proposing genome-scale extensions of existing CAST tools.

DNA Transposable Elements↗
PubMed2026

Microbiota-gut-muscle axis shapes fish muscle texture by regulating collagen synthesis.

BACKGROUND: Increasing studies have emphasized the communication network between the gut microbiome and host organs, revealing that such interactions significantly influence host physiological performances. However, whether a gut-muscle axis exists to regulate muscle quality in animal production is unknown. RESULTS: In two independent cohorts, the muscle hardness of tilapia subjected to a long-term faba bean diet exhibited significant inter-individual variation. RNA-Seq analyses of the high-hardness (H) and low-hardness (L) groups pointed to collagen-based extracellular matrix as a possible factor driving muscle hardness development. Transplantation of gut microbiota from the H donor resulted in enhanced collagen synthesis in gnotobiotic zebrafish. Muscular collagen deposition was featured with an increased abundance of gut Cetobacterium. Gnotobiotic models colonized with live C. somerae exhibited enhanced collagen synthesis. Integrated analyses of microbiome function, bacterial genome, and metabolic profiles identified acetate as a key effector of C. somerae. Acetate incubation upregulated collagen I expression in TGF-β-activated fibroblasts in an acetylation-dependent manner. Mechanistically, acetate promoted the acetylation of SMAD2/3, enhancing its nuclear transport and stability, which ultimately increased collagen expression. An acetate-supplemented feeding experiment corroborated these findings. CONCLUSION: The comprehensive results provided evidences that gut microbes regulated tilapia muscle texture through SMAD2/3 acetylation-driven collagen synthesis. This study expands our understanding of the multifaceted role of the gut-muscle axis in muscle physiology. Furthermore, our findings highlight that targeting gut microbiota and the downstream collagen synthesis pathway could be promising for manipulating muscle quality in animal production. Video Abstract.

Animals↗
PubMed2025

Peering into the Bacterial Cell: From Transcription to Functional Genomics.

I started my faculty career in 1981 at the UW-Madison in the Department of Bacteriology and moved to the University of California, San Francisco in 1993, where I am a Professor in the Departments of Microbiology and Immunology and Cell and Tissue Biology. In this article, I first review my contributions to understanding the molecular biology of the bacterial transcriptional apparatus and the global role of alternative sigmas (σs), a major pillar of bacterial transcriptional control. I then discuss my role in spearheading the development of bacterial systems biology, specifically to the genome-wide phenotyping approaches necessary for rapid understanding of gene function and the molecular basis of pathway connections across the bacterial universe.

Genomics↗
PubMed2026

Unraveling critical role of photosynthetic bacteria in sustaining aquatic microbial community stability and function through large-scale genomic data analyses.

The application of photosynthetic bacteria (PB) in water remediation has demonstrated exceptional advantages in terms of high efficiency and low-carbon benefits. However, the limited understanding of PB across natural aquatic environments has constrained the rational development of this strategy. Here, we analyzed 3198 genomic sequencing samples from seven types of natural aquatic ecosystems to investigate the distribution and functions of 42 PB genera commonly used in water remediation. The results showed that the average abundance of the targeted PB reached 9.83 %, with the highest value of 14.93 % observed in River, while Lake harbored the greatest PB genus diversity. PB genera exhibited high sensitivity to salinity, with Rhodoferax dominating freshwater habitats, whereas Rhodovulum was predominant in marine environments. Notably, co-occurrence network analysis revealed that PB were closely associated with microbial community stability and optimized interspecific interactions. Aquatic microbial communities with high PB abundance were characterized by efficient division-of-labor modules, accompanied by enhanced PB-associated functional potential for carbon fixation, denitrification, and sulfur oxidation. In summary, this study systematically elucidates the regional biogeographical patterns and ecological roles of PB in natural aquatic environments, providing a comprehensive scientific basis and theoretical guidance for the development and practical application of PB-based water remediation technologies.

Bacteria↗
PubMed2026

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↗
PubMed2025

Understanding Mycobacterium tuberculosis through its genomic diversity and evolution.

Pathogen evolution and genomic diversity are shaped by specific host immune pressures and therapeutic interventions. Analysis of the extant genomes of circulating strains of Mycobacterium tuberculosis, a leading cause of infectious mortality that has co-evolved with humans for thousands of years, can provide new insights into host-pathogen interactions that underlie specific aspects of pathogenesis and onward transmission. With the explosion in the number of fully sequenced M. tuberculosis strains that are now paired with detailed clinical data, there are new opportunities to understand the evolutionary basis for and consequences of M. tuberculosis strain diversity. This review examines mechanistic findings that have emerged from pairing whole genome sequencing data and evolutionary analysis with functional dissection of specific bacterial variants. These include improved understanding of secreted effectors that modulate the properties and migratory behavior of infected macrophages as well as bacterial genetic alterations important for survival within hypoxic microenvironments. Genomic, evolutionary, and functional analyses across diverse M. tuberculosis strains will identify prominent bacterial adaptations to their human hosts and shape our understanding of TB disease biology and the host immune response.

Mycobacterium tuberculosis↗
PubMed2025

Exploring phage-host interactions in Burkholderia cepacia complex bacterium to reveal host factors and phage resistance genes using CRISPRi functional genomics and transcriptomics.

Complex interactions of bacteriophages with their bacterial hosts determine phage host range and infectivity. While phage defense systems and host factors have been identified in model bacteria, they remain challenging to predict in non-model bacteria. In this paper, we integrate functional genomics and transcriptomics to investigate phage-host interactions, revealing active phage resistance and host factor genes in Burkholderia cenocepacia K56-2. Burkholderia cepacia complex species are commonly found in soil and are opportunistic pathogens in immunocompromised patients. We studied infection of B. cenocepacia K56-2 with Bcep176, a temperate phage isolated from Burkholderia multivorans. A genome-wide dCas9 knockdown library targeting B. cenocepacia K56-2 was constructed, and a pooled infection experiment identified 63 novel genes or operons coding for candidate host factors or phage resistance genes. The activities of a subset of candidate host factor and resistance genes were validated via single-gene knockdowns. Transcriptomics of B. cenocepacia K56-2 during Bcep176 infection revealed that expression of genes coding for host factor and resistance candidates identified in this screen was significantly altered during infection by 4 h post-infection. Identifying which bacterial genes are involved in phage infection is important to understand the ecological niches of B. cenocepacia and its phages, and for designing phage therapies.IMPORTANCEBurkholderia cepacia complex bacteria are opportunistic pathogens inherently resistant to antibiotics, and phage therapy is a promising alternative treatment for chronically infected patients. Burkholderia bacteria are also ubiquitous in soil microbiomes. To develop improved phage therapies for pathogenic Burkholderia bacteria, or engineer phages for applications, such as microbiome editing, it's essential to know the bacterial host factors required by the phage to kill bacteria, as well as how the bacteria prevent phage infection. This work identified 65 genes involved in phage-host interactions in Burkholderia cenocepacia K56-2 and tracked their expression during infection. These findings establish a knowledge base to select and engineer phages infecting or transducing Burkholderia bacteria.

Bacteriophages↗
PubMed2026

A genomic catalog of Earth's bacterial and archaeal symbionts.

Microbial symbiosis drives the functional and phylogenomic diversification of life on Earth yet remains underexplored because of culturing challenges. This study used machine learning (ML) to predict symbiotic lifestyles in more than a hundred thousand microbial genomes from diverse environmental metagenome samples and reference genomes. Predictions were performed using symclatron, an ML framework developed to identify genomic signatures of symbionts. Predictions were deposited in a catalog we established called Symbiont Genomes (SymGs). The results indicate that 15-23% of uncultivated microorganisms likely engage in symbiotic relationships with other organisms, categorized as host-associated or obligate intracellular lifestyles, and are present in half of all known bacterial and archaeal phyla. We also identify genomic signatures of symbiotic lifestyles, including the loss of certain metabolic functions and the differential presence of metabolic modules that may enable host-dependent living. The symclatron software and the SymGs catalog represent valuable resources for studying symbioses, potentially facilitating future mechanistic investigations and engineering of host-microorganism associations.

Journal Article↗
PubMed2026

Applications of transposon-insertion sequencing for understanding bacterial physiology.

Transposon-insertion sequencing (Tn-seq) couples transposon mutagenesis with next-generation sequencing to identify the transposon insertion site for thousands of mutants in parallel. It is a powerful technology with a myriad of uses beyond the identification of essential genes required for a cell to grow and divide. Tn-seq is particularly useful as a high-throughput method to assign function to function-unknown genes, which have increased steadily with the abundance of newly sequenced bacterial genomes. Tn-seq has now been adapted for use in over 100 bacterial species. Here, we summarize the applications of Tn-seq for querying bacterial physiology and discuss some of the possible applications for the future.

DNA Transposable Elements↗
PubMed2026

CRISPR/Cas9-Mediated Site-Directed Mutagenesis of Genes in Klebsiella pneumoniae.

Constructing target-gene mutants with a common genetic background is crucial for elucidating gene function in antimicrobial resistance (AMR) research. Taking advantage of the single-guide RNA (sgRNA) and protospacer adjacent motif (PAM) sequence (3'-NGG) specificity of the Cas9 protein in the CRISPR/Cas9 (Clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9) system and codon degeneracy, the authors design a repair template that incorporates the desired point mutation while excluding the PAM sequence disrupted by a synonymous substitution, thereby preventing re-cleavage by CRISPR/Cas9. This method employs two available plasmids, pCasKP-apr and pSGKP-spe, offering straightforward operation and high screening specificity. As a result, the approach enables efficient generation of genetically defined mutant strains of Klebsiella pneumoniae (K. pneumoniae) and is readily adaptable to routine laboratory settings. Furthermore, the protocol minimizes off-target editing, shortens experimental timelines, reduces screening workload, and provides a reliable platform for investigating resistance mechanisms, validating candidate genes, and supporting functional genomics studies in clinically relevant bacterial pathogens.

Klebsiella pneumoniae↗
PubMed2026

Enhanced identification of key bacterial motility genes via a cross-species genomic hybrid feature machine learning approach.

Efficient and accurate identification of functional genes is critical to biological research, yet traditional single-species approaches are often limited by low efficiency. Previously, we established a novel method for identifying key genes using cross-species protein domain features and machine learning. However, the high multiplicity of gene members associated with specific domains creates a substantial workload for subsequent experimental validation. To address this, this study proposes an enhanced approach that integrates EggNOG-based protein sequence annotation with domain analysis. Unannotated sequences are subsequently analyzed for protein domains, generating a comprehensive "direct gene annotation plus domain" hybrid feature matrix. While the hybrid matrix model yielded comparable predictive accuracy, it significantly enhanced feature resolution: the top 50 predicted features were all known motility-related genes or domains. Furthermore, among the top 100 ranked features, 58 are confirmed to be directly related to motility based on experimental evidence. Although strict genus-level control still yielded 51 confirmed features, excessive taxonomic restriction drastically reduces the number of training genomes, which may paradoxically impair identification efficiency. These results demonstrate that the new method effectively reduces the subsequent experimental workload and enables high-throughput identification of functional genes in a single analysis. With accuracy and efficiency far exceeding those of existing single-species identification methods, it provides a highly efficient solution for mining key genes underlying other complex bacterial phenotypes.

Machine Learning↗
PubMed2026

DNA polymerase I: structure, activity, and function in bacterial DNA replication and repair.

Faithful replication and repair of the genome are essential processes for all life. Genome maintenance is coordinated by a complex suite of proteins, with bacteria evolving intricate systems despite their relatively simplistic genomes. DNA polymerases are a key class of proteins that mediate genome maintenance. DNA polymerases are all capable of extending nascent strands of DNA but contribute to DNA replication and repair in distinct ways depending on their active site and substrate specificity. The first discovered polymerase, bacterial DNA polymerase I (Pol I), has long been considered the primary enzyme responsible for Okazaki fragment maturation and resynthesis in many DNA repair pathways. These conclusions derive primarily from studies using the gram-negative bacterium, Escherichia coli. Given that some bacterial lineages diverged from E. coli over a billion years ago, these assumptions may not account for evolution in functional diversity. In this review, we examine the structural features of bacterial Pol I and discuss how each of its distinct enzymatic activities contribute to genome maintenance. Throughout, we introduce differences that have been discovered between gram-negative and gram-positive species and explore how activity differences may translate to functional adaptations in replication or repair. We focus on evidence from gram-positive bacteria, particularly Bacillus subtilis and Geobacillus stearothermophilus, that challenges the universality of Pol I's functions and reveals lineage-specific adaptations in replication and repair mechanisms. By synthesizing historical perspectives with recent discoveries, this review underscores both the importance of Pol I and the evolutionary diversification of Pol I in bacterial DNA metabolism.

Bacterial DNA replication↗
PubMed2026

Characteristics and assembly mechanisms of tobacco-associated bacteria in typical tobacco-planting regions across China.

INTRODUCTION: Plant-associated microbiota critically modulates host growth and environmental adaptation, yet assembly mechanisms, niche differentiation, and ecological strategies of bacterial communities inhabiting tobacco microhabitats remain poorly elucidated across geographical gradients. METHODS: Here, we systematically characterized bacterial microbiome assembly across five tobacco-associated niches (bulk soil, rhizosphere soil, root, stem, and leaf) from seven typical tobacco-planting regions using 16S rRNA amplicon sequencing, genome annotation, and niche breadth analysis. The independent and interactive effects of geographical location and host compartment on community structure, and further compared genomic traits, functional profiles, and life-history strategies between specialist and generalist bacterial populations were quantified. RESULTS: The results revealed a deterministic soil-plant continuum stratification of bacterial communities and diversity, with progressively simplified communities and decreasing alpha diversity from bulk soil to above-ground tissues, accompanied by progressive dominance of Proteobacteria. Geographical factors predominantly structured soil microbial communities via divergent edaphic properties, while host filtering acted as a universal dominant driver shaping endophytic microbiome assembly. Niche differentiation analysis demonstrated that niche-specialized bacterial ASVs overwhelmingly dominated all microhabitats and geographical sites, whereas generalist taxa only constituted auxiliary populations. Although specialist and generalist microbes exhibited highly conserved core genomic architectures and overall functional repertoires, they displayed distinct niche-specific functional divergence in metabolic pathways, stress resistance, and secondary metabolism across host compartments. Life-history strategy analysis further revealed that Y-strategist represented the core adaptive bacterial population, especially enriched in above-ground tobacco tissues. DISCUSSION: Our study establishes a hierarchical dual-filtering assembly model for tobacco microbiota, clarifies the ecological differentiation and functional adaptation of specialist and generalist bacteria, and provides fundamental insights into the assembly rules and adaptive mechanisms of crop-associated microbiomes for future microbial resource utilization and agricultural microbiome regulation.

biogeography↗
PubMed2026

Integrated functional genomics and safety assessment of plant-growth-promoting Caryophanales from post-maize-cultivation soils.

This study aimed to evaluate six environmental bacterial strains isolated from post-maize cultivation soils as candidates for agricultural biopreparation development, using an integrated functional genomic and safety assessment framework. Building on experimental validation of plant-growth-promoting activities, the analysis included: plant-growth-promoting traits (PGPT-Pred) using PLABase; carbohydrate-active enzymes (CAZymes) relevant for lignocellulosic crop residue degradation (dbCAN3); secondary metabolite profiles (antiSMASH); and screening for virulence factors and antibiotic resistance genes (ABRicate, BTyper3).All analyzed strains possess 1,449-1,617 predicted PGPT-encoding genes (24.1-35.9% of total genes), which are strongly shaped by taxonomic relatedness, as confirmed by congruence testing against ANI-based genomic divergence. Paenibacillus amylolyticus 5mez and Priestia megaterium 7psych showed distinct functional profiles compared to Bacillus spp., while Bacillus subtilis sensu lato strains were most similar to each other. Genomic predictions suggest involvement in nutrient acquisition (N, P, K, Fe) and stress mitigation. Secondary metabolite analysis revealed high biosynthetic potential, with non-Bacillus species harbouring a large proportion of unknown gene clusters, indicating underexplored metabolite diversity. CAZyme profiling identified P. amylolyticus 5mez as the most enzyme-rich strain, while B. cereus s.s. zielonkawy showed ligninolytic potential despite low overall CAZyme abundance. The safety assessment identified B. cereus s.s. zielonkawy as toxigenic and unsuitable for use. Of the remaining strains, P. amylolyticus 5mez and Pr. megaterium 7psych demonstrated the most favourable safety profiles, exhibiting no detectable virulence factors or antibiotic resistance genes, justifying their priority use in agricultural biopreparations, pending phenotypic validation. Given the high-dimensional, low-sample-size nature of multi-trait datasets in applied microbial genomics, tailored statistical approaches, including noise-reduction-validated PCA and distance-based congruence testing, were applied; their rationale and limitations are discussed.

Soil Microbiology↗
PubMed1977

Biosynthesis of tRNA in histidine regulatory mutants of Salmonella typhimurium.

HisU mutants of Salmonella typhimurium are depressed in the histidine operon since they have lower intracellular concentration of histidyl-tRNAHis. In this paper we present evidences showing that a strain carrying a hisU mutation (hisUl206) is altered in a nucleolytic enzyme involved in tRNA maturation process. The analysis of several hisU mutants indicates that hisU region of bacterial genome may account for more than one function involved in tRNA biosynthesis.

Histidine↗
PubMed2025

Improving the Annotations of JCVI-Syn3a Proteins.

The JCVI-Syn3 organism is a minimal organism derived from Mycoplasma mycoides capri, which is capable of self-replication. While the ancestor has 863 genes, the synthetic progeny has only 473, with 434 of these coding for proteins. Despite initial efforts to understand all functions of the organism, a significant number of these protein-coding genes still have unknown functions, and subsequent studies have been only partially successful in elucidating their roles. In this study, we employ our innovative method PROST to identify homologs and better understand these previously unidentified genes. PROST employs protein language embeddings and enables the identification of remote homologs with as low as 16% sequence identity. PROST successfully finds functionally annotated homologs for 93% of the minimal genome with a high level of accuracy, both confirming previously identified functions, as well as proposing new functions for others. The results of our study can be accessed at https://bit.ly/prost-syn3a .

Molecular Sequence Annotation↗
PubMed2026

Ecological Restoration of the Soil-Like Function in the Bauxite Residue: Natural Microbiomes Mediated Molecular Transformation of Dissolved Organic Matter.

Soilization of bauxite residues offers a scalable route for long-term carbon management and ecological restoration. However, the microbial processes that transform exogenous organic inputs into stable soil-like carbon pools remain poorly resolved. Here, we combined cross-ecosystem meta-analysis, machine-learning prediction, native synthetic community (SynCom) construction, 13C-labeled straw microcosms, field validation, Fourier transform ion cyclotron resonance mass spectrometry, and genome-resolved metagenomics to unravel microbiome-mediated carbon transformation at the dissolved organic matter (DOM) molecular scale. Our meta-analysis revealed that alkaline industrial wastes retained soil-like DOM signatures but were enriched in microbial humic- and protein-like components, indicating active yet incomplete carbon processing. Guided by these patterns, native SynCom inoculation increased 13C incorporation into total organic carbon (TOC) and dissolved organic carbon (DOC), enlarged biodegradable and adsorbable DOC fractions, and shifted DOM from recalcitrant aromatic pools toward oxygenated carbohydrate-, tannin-, and phenolic-like molecular classes. Genome-resolved analyses linked this transformation to complementary polymer degradation and nutrient-cycling functions across fungal and bacterial guilds, including enriched carbohydrate-active enzymes in straw-carbon-utilizing metagenome-assembled genomes. Null model and thermodynamic analyses further showed that microbial communities were constrained by homogeneous selection, whereas DOM molecules were diversified through variable selection and redox-dependent transformation. Field-scale validation confirmed that SynCom promoted TOC and DOC accumulation and humic-like, high-density DOM fractions under alkaline conditions. Together, these findings establish a mechanistic framework in which functional microbiomes couple plant carbon depolymerization, DOM molecular diversification, and mineral-interactive carbon stabilization, providing a microbiome-guided strategy for carbon sequestration and soilization in the bauxite residue.

Soil↗
PubMed2026

Decoding microbial metabolic complementarity from individual traits to community structuring.

A fundamental challenge in microbiome research lies in elucidating the functional capacity of microbial communities through community membership and genomic data. As community structuring and emergent functional traits are determined by bacterial community metabolic networks, it is important to gain insights into the principles that govern bacteria-bacteria interactions. Here, we applied an integrative framework linking individual strain-level traits to community structuring in a simplified synthetic bacterial community (SSC8) that promotes the growth of ungrafted watermelon. By combining mono- and coculture assays with genome-scale metabolic modeling and metabolomic profiling of spent media, we characterized directional interactions and resource dependencies among community members. Our findings show that positive interactions dominated the community network, accounting for 55% of all pairwise combinations, indicating a high prevalence of growth-promoting effects among strains. Genome-scale metabolic modeling showed that functional divergence among strains enhanced the potential for metabolic complementarity as phylogenetic distance increased. Integrating metabolic modeling with metabolomics further suggested that Pseudomonas azotifigens Q6 not only benefited from all other community members, but also exhibited mutualistic interactions with the other three strains, with metabolite exchange involving compounds such as L-lysine and L-cysteine. Pseudomonas azotifigens Q6 acted as an important driver of community composition by affecting the abundance of several other consortium members in vitro. These findings highlight the role of metabolic complementarity in driving community structuring by promoting selective persistence of specific strains. Our work provides mechanistic insights into microbial interaction networks in vitro and offers a conceptual foundation for the rational design of functionally robust and plant-beneficial microbiomes.

Bacteria↗