{"title":"Anti-PD-1 Therapy Alleviates <i>Klebsiella pneumoniae</i>-Induced Liver Abscess by Effectively Activating Kupffer Cells.","authors":"Huaxiu You, Minlie Liang, Houxiong Lin, Ying Liu, Xian Huang, Yuanzhong Gong","doi":"10.4014/jmb.2602.02040","DOIUrl":"https://doi.org/10.4014/jmb.2602.02040","url":null,"abstract":"<p><p><i>Klebsiella pneumoniae</i>-induced liver abscess (KPLA) is the leading cause of pyogenic liver abscess (LA) worldwide. Hepatic Kupffer cells exert protective effects during KPLA progression; thus, elucidating their protective mechanisms and developing novel therapeutic strategies are imperative. A murine KPLA model was established. Hematoxylineosin (HE) staining and tissue bacterial load were analyzed to verify successful <i>K. pneumoniae</i> infection. RT-qPCR, Western blot (WB), and flow cytometry were employed to quantify PD-1 expression in Kupffer cells. PD-1-knockdown Kupffer-cell transfection systems and PD-1-antibody treatment groups were established. Bacterial counts (CFU) and ELISA plus flow cytometry for inflammatory cytokines were used to evaluate the relationship between PD-1 expression and Kupffer-cell bacterial clearance. Finally, the KPLA mouse model was treated with PD-1 antibody to validate the role of PD-1 in LA. In the KPLA mouse model, gross abscess formation was observed, and HE staining revealed disorganized hepatic architecture. PD-1 expression in Kupffer cells was markedly up-regulated, and the proportion of PD-1-positive Kupffer cells increased significantly. <i>In vitro</i>, both PD-1 knockdown and PD-1-antibody treatment enhanced Kupffer-cell bacterial clearance, accompanied by elevated TNF-α, IL-6, and IL-12 levels. <i>In vivo</i>, the PD-1 antibody effectively treated KPLA. KPLA up-regulates PD-1 expression in Kupffer cells, thereby impairing bacterial clearance. Our findings preliminarily indicate that the anti-PD-1 antibody may have application potential in the prevention or early intervention of KPLA.</p>","PeriodicalId":16481,"journal":{"name":"Journal of microbiology and biotechnology","volume":"36 ","pages":"e2602040"},"PeriodicalIF":3.4,"publicationDate":"2026-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149220503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jae Gwang Song, Hyun Jin Bae, Dong Hwan Lee, Joeun Seo, Bomi Lee, Kum-Joo Shin, Eui-Chun Chung, Jeongwook Lee, Hyung Wook Kim, Nam Su Oh
{"title":"Corrigendum to: Preventive Effects of Probiotic Formula on Metabolic Stress Associated Physical Fatigue in Forced Swimming and LPS-Induced Mouse Models.","authors":"Jae Gwang Song, Hyun Jin Bae, Dong Hwan Lee, Joeun Seo, Bomi Lee, Kum-Joo Shin, Eui-Chun Chung, Jeongwook Lee, Hyung Wook Kim, Nam Su Oh","doi":"10.4014/jmb.2026.3606.C06","DOIUrl":"https://doi.org/10.4014/jmb.2026.3606.C06","url":null,"abstract":"","PeriodicalId":16481,"journal":{"name":"Journal of microbiology and biotechnology","volume":"36 ","pages":"e36006"},"PeriodicalIF":3.4,"publicationDate":"2026-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149224353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ha-Young Choi, Duc Dat Le, Bo-Min Kim, Won-Gon Kim
{"title":"A New Simplified Coralmycin Derivative with Potent Anti-Gram-Negative Activity and Its Congeners Produced by the Myxobacterium <i>Corallococcus coralloides</i> M23.","authors":"Ha-Young Choi, Duc Dat Le, Bo-Min Kim, Won-Gon Kim","doi":"10.4014/jmb.2605.05042","DOIUrl":"https://doi.org/10.4014/jmb.2605.05042","url":null,"abstract":"<p><p>Multidrug-resistant (MDR) Gram-negative bacterial infections urgently require new antibacterial agents with novel chemical scaffolds. In our continued investigation of minor metabolites produced by the myxobacterium <i>Corallococcus coralloides</i> M23, we isolated three new coralmycin derivatives, coralmycins J (1), K (2), and L (3), from large-scale fermentation cultures. Spectroscopic analyses revealed that these compounds represent structurally simplified derivatives of coralmycin with varying degrees of truncation. Compounds 1-4 (coralmycins J, K, L, and A) are new natural products isolated in our recent and current studies, while compound 5 (cystobactamid 919-2) is the externally reported reference compound used for comparison. Compound 1 exhibited potent antibacterial activity against both Gram-positive and Gram-negative bacteria and effectively inhibited <i>E. coli</i> DNA gyrase, whereas compounds 2 and 3 showed no detectable biological activity. Structure-activity relationship studies suggested that the <i>β</i>-methoxyasparagine moiety, ring C, or both, are important for antibacterial activity and DNA gyrase inhibition, whereas rings A and B present in compounds 4 and 5 appear to be dispensable. These findings provide valuable insights into the structural simplification of hexapeptidic coralmycins for the development of therapeutic agents against multidrug-resistant Gram-negative bacterial infections.</p>","PeriodicalId":16481,"journal":{"name":"Journal of microbiology and biotechnology","volume":"36 ","pages":"e2605042"},"PeriodicalIF":3.4,"publicationDate":"2026-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149220501","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Transcription Regulatory Sequences in Coronaviruses: Mechanistic Foundations for Antivirals and Vaccines.","authors":"Jinjong Myoung","doi":"10.4014/jmb.2609.09039","DOIUrl":"https://doi.org/10.4014/jmb.2609.09039","url":null,"abstract":"<p><p>Coronaviruses employ a distinctive discontinuous transcription mechanism to generate a nested set of subgenomic mRNAs (sgRNAs) from a single large positive-strand RNA genome. Transcription regulatory sequences (TRSs)-comprising a leader TRS (TRS-L) near the 5' end and multiple body TRSs (TRS-Bs) upstream of downstream open reading frames-serve as the primary <i>cis</i>-acting signals that direct polymerase pausing and template switching during negative-strand synthesis. The COVID-19 pandemic spurred intensive investigation of SARS-CoV-2 gene expression, yielding high-resolution transcriptome maps, genome-wide RNA structure data, and detailed structural models of the replication-transcription complex (RTC). TRS function is therefore best understood as a multi-scale property determined not by the core motif alone, but by the integration of primary-sequence complementarity, local RNA secondary structure, long-range RNA-RNA interactions, and RTC dynamics. This review provides an integrated view of TRS structure-function relationships, with emphasis on how these features collectively shape sgRNA abundance, junction diversity, recombination potential, and prospects for diagnostic and antiviral applications, including vaccines and therapeutics.</p>","PeriodicalId":16481,"journal":{"name":"Journal of microbiology and biotechnology","volume":"36 ","pages":"e2609039"},"PeriodicalIF":3.4,"publicationDate":"2026-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149220180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nu Ri Song, Seo Yeon Shin, Jae Hee Byun, Seon Ju Kim, Hye Young Kim, Won Seok Kim, Kyung Mok Park
{"title":"Skin-Whitening and Anti-Photoaging Activities of <i>Limosilactobacillus reuteri</i> DS0333 Culture Supernatant Produced in Unripe <i>Rubus occidentalis</i> L. Extract-Supplemented Medium.","authors":"Nu Ri Song, Seo Yeon Shin, Jae Hee Byun, Seon Ju Kim, Hye Young Kim, Won Seok Kim, Kyung Mok Park","doi":"10.4014/jmb.2606.06047","DOIUrl":"https://doi.org/10.4014/jmb.2606.06047","url":null,"abstract":"<p><p>This study investigated the skin-whitening and anti-photoaging activities of a culture supernatant obtained by cultivating <i>Limosilactobacillus reuteri</i> DS0333 in chemically defined medium (CDM) supplemented with unripe <i>Rubus occidentalis</i> L. extract (UROE). DS0333 was cultured in UROE-supplemented medium, and the resulting DS0333/(CDM+UROE) group was evaluated alongside all control and comparison groups. The DS0333/(CDM+UROE) culture supernatant showed enhanced DPPH and ABTS radical scavenging activities compared with all other experimental groups. In α-MSH-stimulated B16F10 cells, the culture supernatant reduced melanin content and intracellular tyrosinase activity and downregulated MITF, TRP-1, and TRP-2 expression. In UVB-irradiated human dermal fibroblasts, the culture supernatant increased type I procollagen production, reduced MMP-1 levels, and suppressed MMP-1/MMP-3 expression through attenuation of the MAPK/AP-1 signaling pathway. These results suggest that culturing DS0333 in UROE-supplemented medium enhances skin-whitening and anti-photoaging activities, potentially through cultivation-associated modification of extracellular metabolites in the culture matrix. Therefore, the DS0333/(CDM+UROE) culture supernatant may serve as a promising multifunctional cosmetic ingredient for skin applications.</p>","PeriodicalId":16481,"journal":{"name":"Journal of microbiology and biotechnology","volume":"36 ","pages":"e2606047"},"PeriodicalIF":3.4,"publicationDate":"2026-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149224412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Eui-Jung Han, Sangeun Park, Jiyoung Park, Jae-Hee Lee, Yourim Oh, Jin-Kyu Rhee
{"title":"Formulation of Emulsion Gels Stabilized by Soy Protein Isolate and Gellan Gum Conjugates for 3D Printing and β-Carotene Encapsulation Applications.","authors":"Eui-Jung Han, Sangeun Park, Jiyoung Park, Jae-Hee Lee, Yourim Oh, Jin-Kyu Rhee","doi":"10.4014/jmb.2607.07035","DOIUrl":"https://doi.org/10.4014/jmb.2607.07035","url":null,"abstract":"<p><p>Soy protein isolate-gellan gum (SPI-GG) conjugates were prepared at different mass ratios to investigate how protein-polysaccharide composition affects the physicochemical, emulsion, rheological, and functional properties of CEGs. Increasing the GG proportion enhanced the degree of glycation and Maillard browning while producing opposite trends in solubility and surface hydrophobicity. All SPI-GG CEGs exhibited smaller droplets, more negative ζ-potential values, and higher emulsifying activity and stability than the SPI control. Among the formulations, S1G1 showed the smallest and most uniformly distributed droplets, the highest emulsifying performance, and the greatest β-carotene encapsulation efficiency (90.94 ± 0.55%) and bioaccessibility (68%). In contrast, rheological and printing performance showed a different composition-dependent response. All CEGs exhibited shear-thinning behavior, solid-like viscoelasticity, and thixotropic recovery above 70%. CEG-S1G1.5 exhibited a combination of relatively high G*, critical strain, and yield stress, together with favorable dimensional retention after printing. These findings demonstrate that the SPI-GG ratio differentially affects emulsion characteristics and bulk rheological properties. Overall, the SPI-GG composition associated with favorable functional performance differed according to the intended application, providing a basis for composition-driven design of CEGs for 3D printing and lipophilic bioactive delivery.</p>","PeriodicalId":16481,"journal":{"name":"Journal of microbiology and biotechnology","volume":"36 ","pages":"e2607035"},"PeriodicalIF":3.4,"publicationDate":"2026-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149220495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chaeeun Kang, You-Jeong Kim, Min-Gyung Baek, Aram J Chung, Hana Yi
{"title":"Reduced-Complexity Cultivation of Human Oral Anaerobic Bacteria Using a Microdroplet-Based Culturomics Platform.","authors":"Chaeeun Kang, You-Jeong Kim, Min-Gyung Baek, Aram J Chung, Hana Yi","doi":"10.4014/jmb.2607.07042","DOIUrl":"https://doi.org/10.4014/jmb.2607.07042","url":null,"abstract":"<p><p>The human oral microbiota contains fastidious anaerobes that remain uncultivated due to resource competition and overgrowth by dominant species in conventional plating. Culturomics approaches leveraging droplet-based microfluidics offer an alternative by physically compartmentalizing microbial cells. We established a polydimethylsiloxane-based microdroplet platform to isolate anaerobic bacteria from human oral rinse samples. Droplet generation conditions were optimized using fluorescent beads, and bacterial loading at the collection-drop level was evaluated using <i>Escherichia coli</i>. Two downstream isolation strategies-Direct-plating (Method 1) and Enrichment (Method 2)-were compared against conventional serial dilution across various media compositions. Isolated strains were identified via 16S rRNA gene sequencing. At optimized flow rates (oil: 1.5 mL/h, core: 0.3 mL/h), the system produced uniform microdroplets with an average occupancy (λ) of 0.010-0.012 cells/droplet, corresponding to a high theoretical probability of single-cell occupancy among non-empty microdroplets. Each macro-collection drop delivered approximately 50-60 cells into recipient wells, serving as a reduced-complexity cultivation unit. Under the matched solid-medium condition, Method 1 achieved the highest taxonomic yield (14.3%), representing a 3.5-fold enhancement over conventional serial dilution (4.1%). Method 2 yielded 4.7%, indicating that liquid enrichment reintroduced growth bias toward fast-growing taxa. Among the tested media, unsupplemented Tryptic Soy Agar preserved the highest species diversity, whereas 5% sheep blood supplementation led to monoculture dominance by fast-growing taxa. Overall, the platform isolated diverse oral anaerobic species including fastidious taxa like <i>Capnocytophaga</i>, <i>Cardiobacterium</i>, and <i>Eikenella</i>. The microdroplet-based reduced-complexity platform may limit the dominance of rapidly growing taxa, providing a complementary culturomics tool for expanding human oral anaerobic bacterial resources.</p>","PeriodicalId":16481,"journal":{"name":"Journal of microbiology and biotechnology","volume":"36 ","pages":"e2607042"},"PeriodicalIF":3.4,"publicationDate":"2026-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149220475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kyoung Mi Moon, Min-Kyeong Lee, Su-Yeon Park, Ah-Reum Kim, Bonggi Lee
{"title":"Eicosa-11Z,14Z,17Z-Trienoic Acid Suppresses Melanogenesis by Inhibiting Intracellular MITF/Tyrosinase Axis.","authors":"Kyoung Mi Moon, Min-Kyeong Lee, Su-Yeon Park, Ah-Reum Kim, Bonggi Lee","doi":"10.4014/jmb.2604.04071","DOIUrl":"https://doi.org/10.4014/jmb.2604.04071","url":null,"abstract":"<p><p>Eicosa-11Z,14Z,17Z-trienoic acid (ETA; 20:3 n-3) is an ω-3 polyunsaturated fatty acid whose role in melanogenesis remains unclear. This study investigated the effects of ETA on melanogenesis using α-MSH-stimulated B16F10 melanoma cells and explored the underlying mechanisms. Structural similarity analysis indicated that ETA is closely related to α-linolenic acid, a lipid known to influence pigmentation. ETA showed minimal direct inhibition of mushroom tyrosinase activity in a cell-free system. In cell-based assays, ETA did not induce significant cytotoxicity within the tested concentration range. Under melanogenic conditions, ETA reduced α-MSH-induced melanin accumulation and intracellular tyrosinase activity. This reduction was accompanied by decreased mRNA expression of Tyr, Tyrp1, and Tyrp2, together with reduced protein expression of MITF, tyrosinase, TYRP1, and TYRP2. ETA also attenuated α-MSH-induced phosphorylation of CREB, ERK, and MITF. Immunofluorescence analysis further showed that ETA reduced α-MSH-induced MITF fluorescence intensity, including signals observed in the nuclear region. Taken together, these findings suggest that ETA modulates melanogenesis-related processes in B16F10 cells, likely through mechanisms involving changes in MITF localization and downstream gene expression rather than direct inhibition of tyrosinase activity. These results suggest that ETA may represent a potential candidate for further investigation in the context of pigmentation regulation.</p>","PeriodicalId":16481,"journal":{"name":"Journal of microbiology and biotechnology","volume":"36 ","pages":"e2604071"},"PeriodicalIF":3.4,"publicationDate":"2026-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149220414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jeong Ho Choi, Yeon Ju Kim, Hyun Ju Choi, Duck Hwan Park
{"title":"Effects of Tetracycline Susceptibility and Virulence in an <i>acrR</i> Mutant of <i>Erwinia amylovora</i>.","authors":"Jeong Ho Choi, Yeon Ju Kim, Hyun Ju Choi, Duck Hwan Park","doi":"10.4014/jmb.2608.08022","DOIUrl":"10.4014/jmb.2608.08022","url":null,"abstract":"<p><p>This study investigated whether AcrR-mediated regulation of the <i>acrAB</i> efflux system is associated with tetracycline susceptibility in <i>Erwinia amylovora</i>. We compared tetracycline susceptibility, <i>acrAB</i> expression, intracellular tetracycline accumulation, intracellular pH, ATP-associated luminescence, envelope-associated phenotypes, virulence, and responses to exogenous acyl-homoserine lactones (AHLs) among the wild type (WT), an <i>acrR</i> mutant (Δ<i>acrR</i>), the same mutant after prior tetracycline exposure (Δ<i>acrR</i><sup>Tc</sup>), and an <i>acrR</i>-complemented mutant (Δ<i>acrR</i>(<i>acrR</i>)). Relative to WT, Δ<i>acrR</i> showed fourfold increases in tetracycline MIC and MBC, whereas Δ<i>acrR</i><sup>Tc</sup> showed 16- and 32-fold increases, respectively. Δ<i>acrR</i><sup>Tc</sup> also showed markedly increased <i>acrA</i> and <i>acrB</i> expression, reduced intracellular tetracycline accumulation, lower intracellular pH, and reduced ATP-associated luminescence, suggesting that prior tetracycline exposure was associated with an enhanced AcrAB response in the <i>acrR</i>-deficient background. Δ<i>acrR</i><sup>Tc</sup> further displayed altered cell-envelope ultrastructure, increased <i>waaL</i> expression and lipopolysaccharide (LPS)-associated band intensity, reduced biofilm formation, and a weaker cellulose-associated colony phenotype, whereas amylovoran production and levansucrase-associated activity remained unchanged. In the pathogenicity assay, Δ<i>acrR</i><sup>Tc</sup> produced weaker necrotic symptoms, lower bacterial populations, and reduced <i>in planta dspE</i> expression. Among the AHLs tested, OHHL produced a distinct virulence pattern, with Δ<i>acrR</i> showing reduced disease severity relative to WT and Δ<i>acrR</i>(<i>acrR</i>), whereas this separation was not observed with HHL or OOHL; Δ<i>acrR</i><sup>Tc</sup> remained less virulent under all AHL conditions. These findings support tetracycline as an AcrAB substrate and suggest that prior tetracycline exposure can strengthen the subsequent AcrAB-associated response. The OHHL-specific phenotype further raises the possibility that OHHL may also serve as a substrate of the AcrAB efflux system.</p>","PeriodicalId":16481,"journal":{"name":"Journal of microbiology and biotechnology","volume":"36 ","pages":"e2608022"},"PeriodicalIF":3.4,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13669510/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149172270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jin Joo Lee, Ji-Won Song, Hyeon Jeong Kim, Jung Hoon In, Jisoo Park, Jongsun Park, Seunghun Lee
{"title":"Heat-treated <i>Lactiplantibacillus plantarum</i> MYO Improves Muscle Strength and Modulates Gut Microbiota in Older Adults with Reduced Muscle Strength.","authors":"Jin Joo Lee, Ji-Won Song, Hyeon Jeong Kim, Jung Hoon In, Jisoo Park, Jongsun Park, Seunghun Lee","doi":"10.4014/jmb.2607.07020","DOIUrl":"https://doi.org/10.4014/jmb.2607.07020","url":null,"abstract":"<p><p>Age-related sarcopenia is a condition characterized by a decline in muscle strength and physical function with aging, and its improvement is important given its close association with falls, fractures, and mortality. Recently, as the link between age-related gut microbiota dysbiosis and sarcopenia has been elucidated, modulation of the gut microbiota has gained attention as a therapeutic strategy for sarcopenia. In particular, with growing interest in paraprobiotics, various health-promoting effects-including gut microbiota modulation and improvement of muscle strength-have been reported. However, clinical evidence supporting the association between the gut microbiota and muscle strength remains limited. Accordingly, this clinical study was conducted to investigate the effects of heat-treated <i>Lactiplantibacillus plantarum</i> MYO (LPMYO) intake on quadriceps muscle strength, hand grip strength, muscle quality index (MQI) and gut microbiota composition in older adults with reduced muscle strength, and to examine the correlation between muscle strength and gut microbiota. After 12 weeks of heat-treated LPMYO supplementation, quadriceps muscle strength, hand grip strength and MQI were significantly improved compared with the placebo group. In addition, the abundance of beneficial bacteria, including <i>Faecalibacterium</i>, <i>Lachnospira</i>, <i>Turicibacter</i>, <i>Megasphaera</i>, and the [<i>Eubacterium</i>]_<i>ventriosum</i> group, was significantly increased. Notably, <i>Turicibacter</i> and <i>Megasphaera</i> showed positive correlations with muscle parameters. In addition, enrichment of predicted microbial functions, such as amino acid metabolism, nicotinate and nicotinamide metabolism, and oxidative phosphorylation (OXPHOS), was observed following supplementation with heat-treated LPMYO. Taken together, heat-treated LPMYO significantly improved muscle strength and muscle quality, and these muscle strength-enhancing effects may be associated with alterations in the gut microbiota.</p>","PeriodicalId":16481,"journal":{"name":"Journal of microbiology and biotechnology","volume":"36 ","pages":"e2607020"},"PeriodicalIF":3.4,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149220406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}