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Asymmetric template function of microbial deoxyribonucleic acids: transcription of messenger ribonucleic acid.

In Bacillus subtilis and Escherichia coli, pulse-labeled ribonucleic acid (RNA) synthesized during step-down growth hybridized preferentially with the heavy (H) strand of methylated albumin-Kieselguhr-fractionated deoxyribonucleic acid (DNA). At high RNA inputs, the ratio of RNA hybridized with the H strand to that hybridized with the light (L) strand was 8.7 for B. subtilis and 2.0 for E. coli. At high DNA inputs, the H/L hybridization ratio increased by a factor of two. This change in the hybridization ratio was attributable to the fraction of the pulse-labeled RNA which is in stable RNA components. The hybridization peak of pulse-labeled RNA was specifically located in the late-eluting region of the absorbance profile of the H strand. This region was considered to represent the most actively transcribing H strand templates.

Bacillus subtilis

Optimizing eco-engineering pedogenesis of bauxite residues: Synergistic effects of humus and FeSO4/sulfur on microbial community and function.

Eco-engineered pedogenesis represents a promising approach for soil amelioration of bauxite residues (BRs) through exogenous organic matter. However, the role of humus in mediating this process remains poorly understood, significantly impeding the eco-engineering rehabilitation of BRs. In this study, we conducted pot experiments and subsequent microbial analysis to evaluate the individual improvement of humic acid (HA), fulvic acid (FA), and corn straw (SWZ) on the BRs' pedogenesis. High-throughput sequencing analysis revealed that both FA and SWZ were more effective than HA in steering microbial community assembly, as community diversity, dominant taxa enrichment, and species' interaction were all significantly higher (p < 0.05) in the FA/SWZ treatments than in HA treatments. Notably, the combination of FA with FeSO4 specifically enriched halophilic taxa, while FA coupled with sulfur (S) significantly improved the connectivity and complexity of the microbial network, as the average connection degree increasing from 1.008 to 1.113. Hydrolytic enzyme activity assays further indicated that FA, especially when combined with S, was the most effective treatment in restoring microbial function during BR pedogenesis. These findings highlight FA as a critical driver of microbial restructuring and functional recovery in BRs. Moreover, its efficacy can be enhanced by co-amendment with FeSO4 or S. This study provides important theoretical and practical insights for optimizing organic-inorganic amendment strategies to accelerate the eco-engineering pedogenesis of bauxite residues.

Humic Substances

Data-driven approaches in green microbiology: strategies for plant growth-promoting bacteria.

Plant growth-promoting bacteria (PGPB) are gaining attention as scalable biological solutions to enhance crop productivity and resilience. However, accurately identifying and characterizing PGPB remains challenging, particularly under variable environmental conditions where microbial functions are context-dependent and shaped by complex plant-microbe interactions. Advances in high-throughput sequencing have shifted the field from culture-dependent approaches to genome-informed strategies, enabling large-scale taxonomic and functional profiling. Although trait-based databases support the prediction of plant-beneficial genes, they capture only a fraction of the underlying biological complexity and often require labor-intensive analyses. Machine learning (ML) and deep learning (DL) have emerged as powerful tools to integrate genomic, physiological, and ecological data, enabling the prioritization of candidate strains with plant growth-promoting potential. To evaluate advances in the field, we conducted a systematic review of studies integrating ML and DL with PGPB characterization, assessing algorithm selection, performance, and target plant systems. Across 248 observations, only 6.0% of studies directly addressed PGPB screening, whereas the majority (77.4%) focused on plant disease detection, revealing a substantial gap in the application of AI to beneficial microorganisms for plant growth. Convolutional neural networks (CNNs) were the most frequently applied algorithms, largely driven by image-based phenotyping tasks. Overall, the field is constrained by limited datasets, high computational demands, and challenges in modeling multispecies and host-associated interactions. We highlight the need for integrative and interpretable ML and DL frameworks that bridge genomic data and functional validation. Such approaches represent a promising path toward scalable, data-driven discovery and deployment of bioinoculants in sustainable agriculture.

Agriculture

Microbial toxins, their functional role and phylogenetic validity.

Microbially produced toxins, which appear to lack a role in microbial survival, may be antimicrobial compounds of significance to the producers. These toxin/antibiotics may act against cell metabolism shared by man or animals and other microorganisms. Protein toxin/antibiotics are produced by single species of bacteria. Those from fungi and algae are nonprotein secondary metabolites and several microorganisms may make the same or similar toxin/antibiotics.

Aflatoxins

PICRUSt2-SC: an update to the reference database used for functional prediction within PICRUSt2.

SUMMARY: PICRUSt2 is a bioinformatic tool that predicts microbial functions in amplicon sequencing data using a database of annotated reference genomes. We have constructed an updated database for PICRUSt2 that has substantially increased the number of bacterial (19,493 to 26,868) and archaeal (406 to 1,002) genomes as well as the number of functional annotations present. The previous PICRUSt2 database relied on many timely and computationally intensive manual processes that made it difficult to update. We constructed a new streamlined process to allow regular upgrades to the PICRUSt2 database on an ongoing basis, and used this process to create a new database, PICRUSt2-SC (Sugar-Coated). Additionally, we have shown that this updated database contains genomes that more closely match study sequences from a range of different environments. The genomes contained in the database therefore better represent these environments and this leads to an improvement in the predicted functional annotations obtained from PICRUSt2. AVAILABILITY AND IMPLEMENTATION: PICRUSt2 source code is freely available at https://github.com/picrust/picrust2 and at https://anaconda.org/bioconda/picrust2. The latest version of PICRUSt2 at the time of writing is also archived: https://doi.org/10.5281/zenodo.15119781. The PICRUSt2-SC database comes pre-installed with PICRUSt2 from version 2.6.0 onwards. Step-by-step instructions for making the updated database are at https://github.com/picrust/picrust2/wiki/Updating-the-PICRUSt2-database. All code used for the analyses and figures in this manuscript is at https://github.com/R-Wright-1/PICRUSt2-SC_application_note and https://doi.org/10.5281/zenodo.15119770.

Software

Integrative machine learning models to unravel gut microbial dysbiosis and functional disruption in polycystic ovary syndrome.

OBJECTIVE: To study gut microbial diversity and metabolic pathway disruptions in women with PolyCystic Ovary Syndrome (PCOS) compared with healthy controls, and to evaluate the diagnostic potential of microbiome-driven machine learning models. DESIGN: Case-controlled metagenomic data analysis SUBJECTS: Gut metagenomic data from women diagnosed with PCOS and age-matched healthy female controls EXPOSURE: Presence of PCOS MAIN OUTCOME MEASURES: The primary outcome measures will include gut microbial alpha and beta diversity indices, microbial taxon abundance, functional pathway profiles, predicted metabolite levels, microbe-functional pathway-metabolite interaction networks, and the diagnostic accuracy of microbiome-based machine learning models. RESULTS: Alpha and beta diversity analyses revealed marked gut microbial dysbiosis in women with PCOS, despite comparable species richness to healthy controls. Differential abundance analysis identified 41 significantly altered microbial species, including enrichment of proinflammatory taxa, such as Bacteroides vulgatus and Ruminococcus gnavus, and depletion of beneficial commensals, including Roseburia hominis and Prevotella copri. These compositional shifts indicate a proinflammatory microbial community structure in PCOS. Functional profiling demonstrated the upregulation of pathways involved in nucleotide turnover, lipid and carbohydrate metabolism, and neurotransmitter synthesis, potentially contributing to metabolic and neuroendocrine disruption. Network analysis revealed fragmented and unstable microbial-metabolite associations in PCOS compared with cohesive networks in controls. Microbiome-based machine learning models achieved a diagnostic accuracy of 84.25% (area under the curve 0.93), underscoring their predictive potential. CONCLUSION: The gut microbiome in PCOS is characterized by a proinflammatory community structure and disrupted metabolic pathways. These findings demonstrate the diagnostic potential of microbiome-based models and underscore the gut microbiome as a promising target for therapeutic interventions in the management of PCOS.

Polycystic Ovary Syndrome

Lifestyle Differentiation Among Marine Denitrifying Microorganisms.

Microorganisms carrying out denitrification in marine anoxic zones drive bioavailable nitrogen loss. Sequencing datasets have demonstrated the modularity of denitrification, with most populations having the genetic capability for only a subset of the pathway (NO3-&#x2794;NO2-&#x2794;NO&#x2794;N2O&#x2794;N2). Although previous work provided ecological explanations for this diversity among the functional modules, large trait variations exist within each functional module, and this within-module diversity and its biogeochemical implications remain unexplored. Here, we combine genomic data and modeling to explore how metabolic "lifestyle" strategies influence denitrifier community structure. We build a comprehensive genomic database of marine denitrifiers, and identify lifestyle differentiation among denitrifier functional groups. We then extend a mathematical ecosystem model by resolving two microbial functional types for each module representing a metabolic trade-off: a copiotroph, optimized for fast growth, and an oligotroph, optimized for high nutrient affinity. In the model, as the supply of organic matter relative to nitrate increases, the degree of copiotrophy among the community increases and then decreases. This suggests that oligotrophs are associated with either organic-matter- or nitrate-limiting conditions, whereas copiotrophic lifestyles are associated with an intermediate regime. Our model further associates NO2- reducers with oligotrophy and NO3- reducers with copiotrophy, particularly those producing greenhouse gas nitrous oxide (N2O), linking N2O production to substrate-replete conditions, which is consistent with our genome-based lifestyle estimates. Results provide insight into denitrifier ecological niches and thus the biogeochemical conditions that are associated with the production of intermediates, such as N2O, improving our understanding of how nitrogen cycling will change in a warming ocean.

Marine denitrifiers

Effect of storage on normal neutrophils collected by discontinuous-flow centrifugation leukapheresis.

Storage limits for granulocytes have not been defined. The purpose of this study was to determine these limits for neutrophils collected by discontinuous-flow centrifugation and stored at 4 degrees-6 degrees C. The parameters studied were total leukocyte and absolute cell counts, viability measured by dye exclusion, morphology, percentage phagocytic neutrophils, number of Candida organisms ingested per phagocytic neutrophil, candidacidal activity by differential staining, and chemotaxis under agarose. There was a progressive loss of neutrophils on storage that was statistically significant by 48 hr. Phagocytosis was the best preserved function. Microbial killing measured by candidacidal activity was less well preserved. Chemotaxis was the most poorly maintained parameter. There was mild impairment at 24 hr and a severe functional loss at 48 hr. The data suggest the following: (1) the first functions lost on storage are the most highly integrated, i.e., chemotaxis, followed by microbial killing and then phagocytosis; and (2) assuming that these functional losses are irreversible, storage of normal neutrophils used for transfusion should be limited to approximately 24 hr because a severe defect in migration occurs between the first and second days.

Blood Preservation

Integrated electronic nose, GC-MS, and metagenomic analyses reveal volatile flavor and microbial community differences in heap-fermented grains of Jiangxiangxing Baijiu across different fermentation degrees.

The fermentation degree of heap-fermented grains in Jiangxiangxing Baijiu production is a critical factor influencing base Baijiu quality. However, conventional assessment methods largely rely on empirical experience and therefore suffer from limited objectivity and accuracy. In this study, integrated volatile profiling and metagenomic approaches were employed to investigate volatile characteristics and microbial functional potential differentiation in fermented grains with different fermentation degrees (under-fermented, normally fermented, and over-fermented). Significant differences in physicochemical properties were observed among fermentation degrees, particularly in acidity and reducing sugar content. Electronic nose analysis revealed distinct sensor response patterns among different fermentation degrees, indicating differences in overall volatile odor fingerprint patterns. A total of 81 volatile compounds were identified by HS-SPME-GC-MS, with aldehydes, ketones, and pyrazines showing pronounced variations among fermentation degrees, and acetaldehyde exhibiting strong discriminatory potential. LEfSe analysis identified 18 microbial taxa as potential biomarkers associated with different fermentation degrees, including Pichia kudriavzevii, Lentibacillus daiqui, and Acetobacter pasteurianus. Correlation analysis revealed significant positive associations between acetaldehyde levels and Acetobacter abundance. Furthermore, KEGG, CAZy, and eggNOG analyses revealed differentiated functional potentials among fermentation degrees, providing insights into the potential metabolic basis associated with flavor differentiation. Overall, these findings highlight that fermentation degree differentiation is closely associated with coordinated changes in physicochemical conditions, microbial communities, and functional potentials, providing ecological insights into flavor differentiation and theoretical support for objective fermentation degree evaluation and quality control of Jiangxiangxing Baijiu production.

Fermentation

metaExpertPro: A Computational Workflow for Metaproteomics Spectral Library Construction and Data-Independent Acquisition Mass Spectrometry Data Analysis.

Analysis of large-scale data-independent acquisition mass spectrometry metaproteomics data remains a computational challenge. Here, we present a computational pipeline called metaExpertPro for metaproteomics data analysis. This pipeline encompasses spectral library generation using data-dependent acquisition MS, protein identification and quantification using data-independent acquisition mass spectrometry, functional and taxonomic annotation, as well as quantitative matrix generation for both microbiota and hosts. By integrating FragPipe and DIA-NN, metaExpertPro offers compatibility with both Orbitrap and timsTOF MS instruments. To evaluate the depth and accuracy of identification and quantification, we conducted extensive assessments using human fecal samples and benchmark tests. Performance tests conducted on human fecal samples indicated that metaExpertPro quantified an average of 45,000 peptides in a 60-min diaPASEF injection. Notably, metaExpertPro outperformed three existing software tools by characterizing a higher number of peptides and proteins. Importantly, metaExpertPro maintained a low factual false discovery rate of approximately 5% for protein groups across four benchmark tests. Applying a filter of five peptides per genus, metaExpertPro achieved relatively high accuracy (F-score&#xa0;=&#xa0;0.67-0.90) in genus diversity and showed a high correlation (rSpearman&#xa0;=&#xa0;0.73-0.82) between the measured and true genus relative abundance in benchmark tests. Additionally, the quantitative results at the protein, taxonomy, and function levels exhibited high reproducibility and consistency across the commonly adopted public human gut microbial protein databases IGC and UHGP. In a metaproteomic analysis of dyslipidemia patients, metaExpertPro revealed characteristic alterations in microbial functions and potential interactions between the microbiota and the host.

Proteomics

New techniques for studying digestion and absorption of nutrients by ruminants.

Physical constraints on ruminal digestion have received concentrated research attention in the past 10 years. With scanning electron microscopy, microbial attack and digestion of forage components in the rumen have been observed. Limits to passage through the digestive tract have been explored with digesta flow markers and particle-sizing devices. Diet composition analysis has been simplified by near-IR reflectance. NMR procedures, and histological indexing. Rumen microbial function and genetics are being examined by new procedures and genetically altered microbes are being used for production of specific nutrients. Isolated microbial enzymes are being used in feed analysis. The site of digestion in vivo has received detailed attention with new cannula designs, digesta flow markers, and constitutive microbial markers. Ruminants are being maintained by intragastric or i.v. infusion of purified nutrients to quantitate nutrient requirements. Static and dynamic models of digestive function are aiding in the interpretation of research data. Unfortunately, many new procedures have not been critically standardized against traditional methods. The complexity of certain new techniques and models complicates critical review, publication, and comprehension of research results. The most important laboratory tool for increasing research knowledge is still the alert, fertile human imagination.

Animal Feed

Revealing Functional Traits of Insect Pest Suppressive Rhizobacterial Strains Through Comparative Genomics.

Root inoculation with rhizobacteria is an emerging strategy to enhance plant resistance to aphid herbivory, yet the microbial functional traits underpinning these responses remain poorly characterised. Here, we present a comparative genomic analysis of five rhizobacteria (Acidovorax radicis N35, Bacillus subtilis B171, Bacillus velezensis FZB42, Rhizobium radiobacter F4 and Pseudomonas simiae WCS417r) that suppress aphids when inoculated onto barley. As expected, functional variation largely reflected phylogenetic relatedness; however, candidate traits implicated in modulation of plant immune defences were conserved across all strains, including biosynthesis of 2,3-butanediol, riboflavin and salicylic acid. Additional shared functions, linked to plant defence signalling, included phytoene and squalene biosynthesis (absent in P. simiae) and N-acyl homoserine lactone quorum sensing (absent in Bacillus spp.). Strain-specific traits were also identified, including surfactin production in Bacillus spp. and hydrogen cyanide biosynthesis in A. radicis and P. simiae. Comparison with a broader collection of rhizobacteria revealed that many putative plant-beneficial functions identified were widely conserved, including among closely related phytopathogens. This extensive functional overlap suggests aphid suppression cannot be explained solely by presence or absence of broad functional traits, but rather by specific trait combinations, regulatory differences, or context-dependent expression. This highlights the need for genome-informed approaches for bioinoculant discovery.

Animals

Alleviation of allergic rhinitis symptoms in an animal model by Lactiplantibacillus plantarum BGI-N6.

Allergic rhinitis (AR) is a chronic inflammatory disease with rising global prevalence and a substantial public health burden. Current treatments have limited efficacy and tolerability, highlighting the need for new strategies. Probiotics represent a promising approach due to their ability to modulate gut microbiota and host immunity. Here, we investigated the preventive potential of Lactiplantibacillus plantarum BGI-N6 in an OVA/ALUM-induced AR rat model. BGI-N6 administration alleviated AR symptoms and nasal mucosal pathology, reduced key allergic mediators, shifted serum immunoglobulin and cytokine levels toward normal, and restored the Th1/Th2/Th17/Treg balance. Metagenomic sequencing of cecal contents showed that these effects were accompanied by expansion of Bacteroidota-affiliated SCFA-producing taxa, restoration of microbial functional capacity, and identification of 41 core functional genes (KEGG Orthologues) consistently shifted across all three dose groups, with Bacteroides showing the strongest enrichment. Correlation analyses further connected these microbial shifts with immune parameters. These findings support BGI-N6 as a probiotic intervention for AR and implicate gut microbiota remodeling as a central correlate of probiotic-induced immunomodulation.

Animals

Synergic impact mechanisms of cover crop residue on Cd and As availability and native organic carbon mineralization in Cd and As co-contaminated paddy soil.

The synergic impacts of cover crop residue on heavy metal and metalloid availability and soil organic carbon (SOC) mineralization in contaminated paddy soil and the underlying microbial mechanism remain unclear. This study investigated the availability of cadmium (Cd) and arsenic (As) and mineralization of native SOC in paddy soil treated with 0, 0.4&#x202f;%, 0.8&#x202f;% and 1.2&#x202f;% of &#x3b4;13C-labeled cover crop residue (Astragalus sinicus L.) via 90-day incubation experiments, the related functional genes and functional microbial communities were analyzed using metagenomic binning assembly. Cover crop residue with addition rate from 0.4&#x202f;% to 1.2&#x202f;% significantly decreased available Cd by 56&#x202f;%-85&#x202f;% but increased available As by 39&#x202f;%-66&#x202f;% compared to the control treatment. Cover crop residue resulted in a positive priming effect on native SOC mineralization but benefited SOC sequestration. Cover crop residue increased the abundance of genes encoding iron reductase (mtrABC, pilA, omcB), sulfate reductase (sir, fpr), As(V) reductase (ArsC), organic carbon hydrolases, methanogenesis, and methylotrophy. Genomes associated with Chloroflexota and Bacteroidota encoded all these key pathways, and their abundance increased with cover crop residue application. Cover crop residue decreased soil Eh, dissolved crystalline iron oxides, enriched specific microorganisms, including Chloroflexota and Bacteroidota, and then synergistically promoted the decrease in Cd availability and the increase in As availability and native SOC mineralization in the examined paddy soil. These findings provided practical and feasible guidance for achieving both safe production and carbon sequestration in contaminated paddy fields, highlighting the requirement to cautious utilization of cover crop residue in As-contaminated paddy fileds.

Soil Pollutants