Mycobacterium tuberculosis, a lethal pathogen in human history, causes millions of deaths annually, which demands the development of new concepts of drugs. Considering this fact, earlier research has explored the anti-tuberculosis potential of a probiotic strain, Lactocaseibacillus rhamnosus PMC203, leading to a subsequent focus on the molecular mechanism involved in its effect, particularly on autophagy. In this current study, immunoblotting-based assay exhibited a remarkable expression of autophagy marker LC3-II in the PMC203 treated group compared to an untreated group. A remarkable degradation of p62 was also noticed within treated cells compared to control. Furthermore, the immunofluorescence-based assay showed significant fold change in fluorescence intensity for alexa-647-LC3 and alexa-488-LC3, whereas p62 was degraded noticeably. Moreover, lysosomal biogenesis generation was elevated significantly in terms of LAMP1 and acidic vesicular organelles. As a result, PMC203-induced autophagy played a vital role in reducing M. tuberculosis burden within the macrophages in treated groups compared to untreated group. A colony -forming unit assay also revealed a significant reduction in M. tuberculosis in the treated cells over time. Additionally, the candidate strain significantly upregulated the expression of autophagy induction and lysosomal biogenesis genes. Together, these results could enrich our current knowledge of probiotics-mediated autophagy in tuberculosis and suggest its implications for innovatively managing tuberculosis.

Lactic acid bacteria (LAB), traditionally consumed as fermented foods, are now being applied to the medical field beyond health-functional food as probiotics. Therefore, it is necessary to continuously discover and evaluate new strains with suitable probiotic characteristics, mainly focusing on safety. In this study, we isolated eight new strains from postmenopausal vaginal fluid using culturomics approaches, an emerging area of interest. Data showed that most strains possessed significant cell surface hydrophobicity (≥ 76%), auto-aggregation capacity (17 to 61%), strong adhesion activity (8 to 34%), and excellent resistance to gastric acid, bile salt, and digestive enzyme, enhancing their survival in the gastrointestinal tract. Moreover, the strains exhibited functional characteristics, including substantial antibacterial activity with a minimal inhibitory concentration (MIC) ranging from 12.5 to 50%. They also harbored bacteriocins genes, produced short-chain fatty acids (acetate and propionate), exhibited significant phagocytic activity, possessed high antioxidative properties, rapidly depleted sodium nitrite, and exhibited proteolysis and β-glucosidase activity. In addition, heat-killed LAB strains significantly reduced the gene expressions of proinflammatory cytokines such as IL-β, IL-6, and iNOS in macrophages. Safety assessment revealed no cytotoxicity in macrophage cell lines. All strains tested negative for biogenic amine or H₂O₂ production, displayed no gelatinase or hemolytic activity, lacked virulence genes or detrimental enzymes, and displayed antibiotic susceptibility. In summary, these newly isolated strains demonstrate excellent probiotic functionality with a strong focus on safety, making them promising candidates for future drug development in the relevant fields.

Background: The involvement of the intratumoral microbiome in prostate cancer progression is becoming increasingly acknowledged. This study analyzed the microbiome of prostate cancer tissues from patients with localized prostate cancer (LPC, stages 1–2) and advanced prostate cancer (APC, stages 3–4) to determine its association with cancer progression. Methods: Paraffin-embedded tissue samples obtained during radical prostatectomy underwent 16S rRNA amplicon-based profiling. Results: The profile of the bacterial communities in LPC and APC differed remarkably. While species diversity remained stable, species richness (as determined by the ACE analysis) was significantly lower in APC, correlating with a decrease in Enhydrobacter (which is more abundant in LPC) and an increase in Lautropia (enriched in APC). The role of Lautropia in the progression of cancer was confirmed by in vitro studies employing cell lines from prostate cancer. Conclusions: These findings demonstrate the potential of microbiome-targeted interventions in the management of prostate cancer.

Background/Objectives: Traditionally consumed fermented foods and lactic acid bacteria (LAB)-based products have primarily been investigated for their nutritional and health-promoting benefits as dietary supplements. More recently, research has advanced toward exploring their therapeutic potential in pharmaceutical development. However, reliance on conventional LAB strains despite their established safety and efficacy has led to saturation at the strain level, underscoring the need for next-generation probiotics (NGPs) with novel therapeutic potential. In this context, we identified Flavonifractor plautii from human feces as a candidate NGP and investigated its effects on the human gut microbiota. Methods: Whole-genome sequencing revealed distinct genetic features that supported its uniqueness, and the strain was designated PMC93. A human gut microbial ecosystem simulator was used to administer F. plautii daily for one week, after which microbial community changes were evaluated using 16S rRNA gene-based metagenomic sequencing. Results: The administration did not induce significant changes in alpha or beta diversity, suggesting that F. plautii does not disrupt overall bacterial community structure, thereby supporting its microbial community safety. Taxonomic analysis demonstrated a significant increase in the Firmicutes-to-Proteobacteria ratio (NGP F/P index). The improvement surpassed that of conventional LAB treatments and was consistently maintained under supplementation with commonly encountered pharmaceutical compounds and nutrients. The shift was associated with an increase in short-chain fatty acid (SCFA)-producing beneficial taxa and a decrease in pro-inflammatory and potentially pathogenic groups. Functional outcomes, including elevated SCFA levels and downregulation of inflammation-related gene expression, further corroborated these compositional changes. The strain also demonstrated safety in in vivo models. Conclusions: Collectively, these findings suggest that strain PMC93 is a promising NGP candidate with substantial therapeutic potential for microbiota-associated health and disease modulation, particularly due to its ability to enhance the NGP F/P index.

Fatemeh Ghorbanian, Hoonhee Seo, Faezeh Sarafraz, Ali Atashi, Md Sarower Hossen Shuvo, Park Chae-eun, Mohammed Solayman Hossain, Hanieh Tajdozian, Sukyung Kim, Ho-Yeon Song, and Heejo Yang. J. Microbiol. Biotechnol. 2025;35:1-12. https://doi.org/10.4014/jmb.2506.06025

Gout is an inflammatory arthritis resulting from the deposition of monosodium urate crystals. Urate-lowering therapies for gout have limitations, including side effects and limited efficacy, highlighting the need for novel therapeutic approaches to improve patient outcomes. In this context, our research team conducted a microbiome analysis of fecal samples from healthy individuals and gout patients, identifying Bifidobacterium as a key biomarker. Subsequently, we isolated and identified this strain, B. longum PMC72, and demonstrated its efficacy in a gout mouse model. In potassium oxonate (PO)-induced hyperuricemia mice, PMC72 significantly alleviated nausea, gait disturbances, ankle inflammation, and improved renal health. These effects were associated with marked reductions in oxidative stress markers, including serum uric acid, blood urea nitrogen, hepatic xanthine oxidase, and malondialdehyde (MDA) levels in serum, liver, and joint samples, as well as the downregulation of inflammation and uric acid transport-related gene expression in kidney samples. These benefits were comparable to those treated with Febuxostat, a standard urate-lowering therapy for gout. Furthermore, gut microbiome analysis revealed that PMC72 restored dysbiosis induced by hyperuricemia, contrasting with the reduced microbial diversity observed with febuxostat alone, and showed a complete recovery to eubiosis when combined with Febuxostat. These findings position PMC72 as a promising microbial therapeutic candidate for gout management, demonstrating significant development potential and serving as a benchmark for reverse translational microbiome-based therapeutic research.