Archives of Microbiology最新文献

{"title":"Gluconacetobacter diazotrophicus as a plant growth-promoting endophyte: mechanistic insights and translational prospects for sustainable agriculture","authors":"Anusha Suresh,&nbsp;Surender Singh","doi":"10.1007/s00203-026-05193-x","DOIUrl":"10.1007/s00203-026-05193-x","url":null,"abstract":"<div><p>With the growing interest in sustainable agriculture, there has been a surge in exploration of multitrophic interactions between plants and microbes that can help plants adapt to changing environments and enhance their resilience to climate changes. One such beneficial microbe is <i>Gluconacetobacter diazotrophicus</i>, an aerobic, nitrogen-fixing endophyte currently being studied because of its ability to fix atmospheric nitrogen within plant tissues under aerobic conditions. This endophyte also promotes plant growth through processes like phytohormone production, nutrient solubilization, and improved stress tolerance of the plant. Recent advances in genomics and systems biology have provided valuable insights into the metabolism, interactions, and functions of this microorganism inside the host plants and its contribution to rhizosphere and endosphere dynamics. Despite considerable advances in understanding this organism, there are still limitations to its application due to its poor field performance, environmental variations, and difficulties in formulation production. This review consolidates the current knowledge on the ecology, physiology, and molecular mechanisms of <i>Gluconacetobacter diazotrophicus</i>, critically assesses its limitations, and identifies future research priorities to enhance its translational potential.</p></div>","PeriodicalId":8279,"journal":{"name":"Archives of Microbiology","volume":"208 12","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148975268","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The community patterns and assembly mechanism varied in eukaryotic microorganisms with different cell sizes","authors":"Wei Hu,&nbsp;Xiaofan Zhao,&nbsp;Zenghui Zhang,&nbsp;Yumei Qian,&nbsp;Xinxin Lai,&nbsp;Kexin Zhang,&nbsp;Pengfei Yang,&nbsp;Zongcan Yang,&nbsp;Hanghang Han","doi":"10.1007/s00203-026-05164-2","DOIUrl":"10.1007/s00203-026-05164-2","url":null,"abstract":"<div><p>Cell size is a fundamental determinant of eukaryotic microorganisms’ ecology, influencing community dynamics, physiological processes, and ecological interactions. However, it is still unclear whether eukaryotic microorganisms of different size have similar structural and assembly mechanisms. In this study, we sorted eukaryotic microorganisms’ cells into two sizes classes (large-sized eukaryotic microorganisms (LE) and small-sized eukaryotic microorganisms (SE)) and compared their structural and assembly mechanisms along the Han River. The results showed that LE fractions had higher diversity compared to SE fractions, the two size classes harbored distinct eukaryotic microorganisms’ communities. And. Assembly mechanisms of the two classes were significantly different. We conclude that cell size is an important factor that determines eukaryotic microorganisms’ structure and assembly mechanisms. These findings underscore the critical role of cell size in determining eukaryotic microorganisms’ community and uncover a direct relationship between microbial morphology and ecological traits.</p></div>","PeriodicalId":8279,"journal":{"name":"Archives of Microbiology","volume":"208 12","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00203-026-05164-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148975615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A hybrid statistical–machine learning framework for optimization, prediction, and model-fitting of xylose and total sugar production from sugarcane bagasse using recombinant Escherichia coli-mediated hydrolysis","authors":"Ayush Saxena,&nbsp;Akhtar Hussain,&nbsp;Fouziya Parveen,&nbsp;Mohd Khubaib,&nbsp;Mohammad Ashfaque","doi":"10.1007/s00203-026-05178-w","DOIUrl":"10.1007/s00203-026-05178-w","url":null,"abstract":"<div><p>Efficient conversion of lignocellulosic biomass utilizing microbes to release fermentable sugars remains a major challenge. This study reports the integrated process involving <i>Trichoderma reesei</i> for pretreatment and recombinant whole-cell <i>Escherichia coli</i> expressing endo-β-1,4-xylanase for hydrolysis. Maximum cellulase activity 178.61 ± 1.98 IU/g dry substratewas observed on the 10th day at pH 5.5 during pretreatment. A Box-Behnken Design was applied to optimize the reducing sugar (xylose equivalent) and total sugar production during hydrolysis. The maximum reducing sugar (xylose equivalent) was 589.8 µg/mL, and the total sugar was 7785.6 µg/mL, achieved after 6 h and 24 h of induction, respectively. ANOVA demonstrated significant models with strong predictive performance, R² = 0.9866 for reducing sugar (xylose equivalent) and 0.9815 for total sugar. Machine learning predictions using Support Vector Machine (SVM) and Artificial Neural Network (ANN) identified SVM as the superior predictive model. Structural changes in the process strategies were confirmed using compositional analysis, XRD, FE-SEM, and FTIR. Overall, this strategy provides an efficient insight into the biological degradation of SCB for sustainable sugar production.</p></div>","PeriodicalId":8279,"journal":{"name":"Archives of Microbiology","volume":"208 12","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148975655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An integrative computational and experimental evaluation of natural compounds with potential to target LuxS in Klebsiella pneumoniae","authors":"Mashego Jackson Mamosebo,&nbsp;Suheena Ayrga,&nbsp;Shabir A. Madhi,&nbsp;Shama Khan","doi":"10.1007/s00203-026-05191-z","DOIUrl":"10.1007/s00203-026-05191-z","url":null,"abstract":"<div><p><i>Klebsiella pneumoniae</i> (<i>KPn</i>) has emerged as a major global health concern due to increasing antimicrobial resistance (AMR). The development of new antimicrobial agents is essential to address multidrug-resistant and emerging hypervirulent strains associated with increased morbidity and mortality worldwide. In this study, an integrative computational–experimental approach was employed to characterise the anti-quorum sensing and anti-biofilm activities of selected natural compounds targeting the LuxS/autoinducer-2 (AI-2) system in <i>KPn</i>. Six compounds were initially screened using homology modelling, molecular docking, pharmacophore analysis, and molecular dynamics (MD) simulations. Resveratrol, quercetin, and epigallocatechin gallate showed favourable binding to LuxS. Although quercetin (ΔG_bind = − 45.47 kcal/mol) and epigallocatechin gallate (− 43.04 kcal/mol) exhibited stronger predicted affinities than resveratrol (− 39.22 kcal/mol), resveratrol demonstrated superior complex stability (RMSD: 1.8 ± 0.2 Å) and persistent interactions with key residues (Tyr63, Trp68). Experimental validation demonstrated that resveratrol exhibited significant antimicrobial activity (MIC/MBC = 32 µg/mL), significantly inhibited quorum sensing-associated phenotypes, and reduced <i>KPn</i>-<i>Acinetobacter baumannii</i> (<i>ABa</i>) dual-species biofilm formation inhibition by 54.7%. These findings identify resveratrol as a promising anti-virulence candidate and highlight the utility of integrative computational and experimental strategies for the identification of compounds targeting quorum sensing and biofilm formation inhibition in multidrug-resistant pathogens.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div><div><p>Graphical abstract showing natural compounds investigated in this study and their interaction with the LuxS protein, a key regulator of quorum sensing in <i>Klebsiella pneumoniae</i></p></div></div></figure></div></div>","PeriodicalId":8279,"journal":{"name":"Archives of Microbiology","volume":"208 12","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00203-026-05191-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148975160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular and regulatory aspects of EPA: a Nakaseomyces glabratus epithelial adhesin","authors":"Bhawana Yadav,&nbsp;Celia Fortuna Rodrigues,&nbsp;Payal Gupta","doi":"10.1007/s00203-026-05210-z","DOIUrl":"10.1007/s00203-026-05210-z","url":null,"abstract":"<div><p><i>Nakaseomyces glabratus</i> has been recognized worldwide as a formidable fungal pathogen, mostly associated with healthcare-related infections. It leads to persistent and recurrent infections due to its ability to form biofilms on medical devices and its innate resistance to antifungals. The first step in biofilm formation is the adhesion of fungal cells to the surface. Epithelial adhesins (EPAs), a family of glycosylphosphatidylinositol (GPI)-anchored cell wall proteins, play a central role in mediating adhesion. The EPA genes are located in sub-telomeric regions and are tightly regulated by the Sir silencing complex, epigenetic modifications, and environmental factors such as nicotinic acid limitation. Sub-telomeric silencing ensures phenotypic plasticity. EPA paralogs bind to the host glycans via PA14 domains with calcium-dependent interactions, while hydrophobic interactions facilitate adhesion to abiotic surfaces. Synergistic actions of transcription factors and stress-responsive regulators contribute to EPA-mediated biofilm development. The strain-specific diversity and redundancy in EPA paralogs challenge therapeutic targeting of adhesins. However, like <i>Candida albicans</i> Als3 inhibitors, galactose analogs, Sir2 inhibitors and monoclonal antibodies are a few promising anti-adhesion strategies. This review broadly discusses the molecular and regulatory mechanisms governing EPA function in <i>N. glabratus</i>, its role in biofilm development, and its role in host-pathogen interactions. By elucidating EPA’s multifaceted regulation, its therapeutic potential can be understood, paving the way for novel avenues to combat resilient infections.</p><h3>Graphical abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":8279,"journal":{"name":"Archives of Microbiology","volume":"208 12","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148975323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced terpenoid synthesis in Alternaria alstroemeriae PPL7 via co-fermentation with Paeonia lactiflora roots: integrated metabolomic and transcriptomic analysis","authors":"Songlin Jin,&nbsp;Yinde Lu,&nbsp;Yingjie Yang,&nbsp;Jin Su,&nbsp;Lihong Wang","doi":"10.1007/s00203-026-05177-x","DOIUrl":"10.1007/s00203-026-05177-x","url":null,"abstract":"<div><p>Total glucosides of paeony (TGP), primarily composed of monoterpene glycosides such as paeoniflorin and albiflorin, possess diverse pharmacological activities, including anti-inflammatory and neuroprotective effects. Traditional extraction from plants is limited by long growth cycles and low active content. This study employs an integrated metabolomics and transcriptomics strategy to systematically elucidate the molecular regulatory network underlying the biosynthesis of terpenoids by the <i>Paeonia lactiflora</i> leaf endophytic fungus <i>Alternaria alstroemeriae</i> PPL7 within a root co-fermentation system. Under the optimal root powder supplementation level (1.17%, w/v), the yield of target terpenoids increased significantly. Multi-omics comparative analysis revealed a global metabolic reprogramming induced by co-fermentation: the terpenoid backbone biosynthesis pathway was significantly enriched, and key terpenoid components (e.g., paeoniflorin) were upregulated. This was accompanied by fine-tuned flux regulation of the upstream mevalonate (MVA) pathway, enhanced precursor supply at mid-stream nodes, and metabolic diversion via protein prenylation. The synergistic activation of central carbon metabolism and amino acid degradation provided the necessary energy and reducing power for efficient terpenoid synthesis. This study not only elucidates the adaptive mechanisms by which endophytic fungi remodel their metabolic networks to efficiently synthesize plant-derived terpenoids but also provides novel strain resources and a theoretical basis for the sustainable manufacturing of terpenoid natural products using synthetic biology strategies.</p></div>","PeriodicalId":8279,"journal":{"name":"Archives of Microbiology","volume":"208 12","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148975246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Screening and identification of B-cell epitopes on the gH protein of varicella-zoster virus","authors":"Chao Liang,&nbsp;Yuge Ma,&nbsp;Hongliang Liu,&nbsp;Jingming Zhou,&nbsp;Yumei Chen,&nbsp;Yanhua Qi,&nbsp;Xifang Zhu,&nbsp;Enping Liu,&nbsp;Sixuan Wu,&nbsp;Aiping Wang","doi":"10.1007/s00203-026-05155-3","DOIUrl":"10.1007/s00203-026-05155-3","url":null,"abstract":"<div><p>Varicella and herpes zoster are two clinically distinct diseases caused by varicella-zoster virus (VZV). The VZV envelope is enriched with multiple glycoproteins, among which glycoprotein H (gH) is a key envelope glycoprotein essential for viral entry into host cells and an important target of neutralizing antibodies. However, precise mapping of key protective epitopes on the gH protein remains incomplete. VZV gL functions as a molecular chaperone for gH and promotes its proper expression. In this study, the extracellular-domain sequence of gH and the full-length sequence of gL were co-cloned into the pCGS3 vector, and the VZV gH/gL heterodimer with native conformation was successfully expressed using a eukaryotic expression system. Using this heterodimer as the immunogen, five monoclonal antibodies (mAbs) specifically recognizing gH were obtained. Through overlapping peptide truncation assays, the linear B-cell epitopes targeted by these five mAbs were mapped to two regions of the gH protein: ⁴³¹SQLHDELSLLFGQVK⁴⁴⁵ and ⁷⁷⁵SKAVLLFPNGTVVTL⁷⁸⁹, and alanine scanning mutagenesis further identified the key amino acid residues recognized by each mAb. This study successfully identified linear B-cell epitopes on the VZV gH protein at single-residue resolution, and both epitopes were completely conserved among 40 VZV strains. The two linear epitopes identified in this study provide valuable experimental materials for further dissecting the molecular mechanisms of the host anti-VZV immune response and lay a sequence foundation for subsequent optimization and design of epitope-based immunogens.</p></div>","PeriodicalId":8279,"journal":{"name":"Archives of Microbiology","volume":"208 12","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148975540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Salinimicrobium molybdatiresistens sp. nov., a novel molybdate-resistant and selenite-reducing bacterium isolated from river silt","authors":"Jinhua Hu,&nbsp;Kaiyue Wang,&nbsp;Jia Wang,&nbsp;Yuelin Liu,&nbsp;Yanfang Zhao,&nbsp;Qili Zhang,&nbsp;Zhenbiao Xu,&nbsp;Linxia Song,&nbsp;Shuzhen Wei,&nbsp;Rui Zhang,&nbsp;Hongliang Liu","doi":"10.1007/s00203-026-05181-1","DOIUrl":"10.1007/s00203-026-05181-1","url":null,"abstract":"<div><p>Strain TH3^T was isolated from the river bottom silt collected in Hengshui, Hebei Province, China. The bacterium is a yellow-pigmented, rod-shaped, Gram-staining negative and aerobic organism. It was able to grow between 10 and 37 °C (optimum 30 °C), at pH values from 5.0 to 9.0 (optimum pH 7.0), and tolerated NaCl concentrations ranging from 0 to 13% (w/v, optimum 2%). The 16 S rRNA gene sequence of strain TH3^T was found to be most closely related to <i>Salinimicrobium sediminilitoris</i> ASW11-47^T (99.7%). Nevertheless, genome comparison revealed the relatedness indices below species delineation thresholds: digital DNA–DNA hybridization was 49.7%, and average nucleotide identity was 93.2%, and average amino acid identity was 94.2% compared to <i>Salinimicrobium sediminilitoris</i> ASW11-47^T. Strain TH3^T had a genome size of 3.7 Mb and a DNA G + C content of 41.0%. The major fatty acids observed for strain TH3^T (≥ 5%) were iso-C_14:0, iso-C_15:0, anteiso-C_15:0, iso-C_16:0, iso-C_16:0 3-OH, iso-C_17:0 3-OH, and summed feature 3. The polar lipid composition included phosphatidylethanolamine, one unidentified phospholipid, two aminolipids, along with five unknown lipids. The sole respiratory quinone in strain TH3^T was menaquinone-6. In addition, strain TH3^T was highly resistant to molybdate (500 mM) and selenite (20 mM), and could completely reduce 1 mM selenite to red elemental SeNPs within 3 d. Strain TH3^T contains several putative selenite-reducing genes, including <i>sodA</i>, <i>serA</i>, <i>serC</i>, <i>cysH</i>, <i>deoC</i>, <i>tktA</i>, and <i>pdhC</i>. Based on polyphasic characterization, strain TH3^T was found to be a novel species in the genus <i>Salinimicrobium</i>, and the proposed name is <i>Salinimicrobium molybdatiresistens</i> sp. nov. The type strain is TH3^T (= GDMCC 1.3399^T = JCM 35713^T).</p></div>","PeriodicalId":8279,"journal":{"name":"Archives of Microbiology","volume":"208 12","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148975609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hybrid genome assembly of Penicillium oxalicum UV4 delineates cryptic secondary metabolite pathways and robust lignocellulolytic potential","authors":"Mohamad Ayham Shakouka,&nbsp;Pooja Parmar,&nbsp;Deeba Kamil,&nbsp;S. T. Prashantha,&nbsp;Jagdish Yadav,&nbsp;Himanshu Dubey,&nbsp;Gopala Krishnan Subbaiyan,&nbsp;Bishnu Maya Bashyal","doi":"10.1007/s00203-026-05176-y","DOIUrl":"10.1007/s00203-026-05176-y","url":null,"abstract":"<div><p><i>Penicillium oxalicum</i> is a saprophytic fungus well-known for its hydrolytic potential; however, little is known about its metabolic flexibility and secondary metabolite biosynthesis, especially in isolates from underrepresented areas. In this study, we sequenced the genomic DNA of <i>Penicillium oxalicum</i> UV4 using Illumina and Oxford Nanopore platforms, generating a high-quality hybrid genome assembly of 30.28 Mb. The genome features 7,944 predicted genes (7,747 protein-coding sequences and 197 tRNAs) and demonstrates high completeness (99.0% BUSCO). Genomic analysis revealed 40 Biosynthetic Gene Clusters (BGCs), including distant orthologs of the <i>Alternaria</i> phytotoxin ACT-toxin II and the mycotoxin alternariol, as well as a putative clavaric acid-like biosynthetic cluster. Further investigation revealed an expanded CAZyme repertoire comprising 150 secreted proteins, featuring an AA16 lytic polysaccharide monooxygenase and putative multi-domain architectures, such as a pectin methylesterase-polygalacturonase fusion. This comprehensive genomic profiling highlights the dynamic metabolic capacity of <i>P. oxalicum</i> UV4, establishing it as a highly promising candidate for bio-refining studies and the discovery of cryptic bioactive metabolites.</p></div>","PeriodicalId":8279,"journal":{"name":"Archives of Microbiology","volume":"208 12","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148975286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Screening of largemouth bass-derived Bacillus subtilis and synergistic regulation of growth performance, intestinal health, and resistance against Edwardsiella piscicida infection","authors":"Yujun Zhang,&nbsp;Jiahao Zhang,&nbsp;Yuan Liang,&nbsp;Weimin Huang,&nbsp;Wenhao Wu,&nbsp;Xinxin Chen,&nbsp;Biao Jiang,&nbsp;Youlu Su","doi":"10.1007/s00203-026-05183-z","DOIUrl":"10.1007/s00203-026-05183-z","url":null,"abstract":"<div><p>In this study, 49 intestinal bacterial isolates were recovered from healthy <i>Micropterus salmoides</i>, among which five candidate <i>Bacillus subtilis</i> strains were screened via multi-index in vitro evaluation. An 8-week feeding trial covering six treatment groups was conducted to assess growth performance and survival upon <i>Edwardsiella piscicida</i> immersion challenge. Two strains (YB-4 and YB-15) with 95% disease protection rates were selected for further intestinal histological, biochemical and qRT-PCR analyses. Dietary supplementation with YB-4 and YB-15 significantly improved feed conversion efficiency, increased intestinal villus height and muscular layer thickness, enhanced tissue antioxidant capacity, and modulated inflammatory and humoral immune gene expression toward an anti-inflammatory profile. Notably, YB-4 and YB-15 exhibited tissue-specific divergent regulation of key cytokines including <i>TGF-β</i> and <i>IgM</i>, representing a rarely reported strain-dependent immune characteristic of bass-derived <i>B. subtilis</i>. Collectively, YB-4 and YB-15 are promising autochthonous probiotic candidates that simultaneously promote growth, maintain intestinal homeostasis and defend against <i>E. piscicida</i> infection, providing targeted strain-based strategies to reduce antibiotic reliance in largemouth bass intensive aquaculture.</p></div>","PeriodicalId":8279,"journal":{"name":"Archives of Microbiology","volume":"208 12","pages":""},"PeriodicalIF":3.4,"publicationDate":"2026-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148975575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}