Microbiology and Immunology最新文献

{"title":"Development and Application of a Rapid 23S rRNA-Targeted Reverse Transcription Quantitative PCR System for the Detection and Quantification of Enterobacterales.","authors":"Satomi Atobe, Mai Hane, Akira Takahashi, Yukiko Kado, Rie Date, Shuta Yamamoto, Takashi Asahara","doi":"10.1111/1348-0421.70096","DOIUrl":"https://doi.org/10.1111/1348-0421.70096","url":null,"abstract":"<p><p>Bacteria belonging to the family Enterobacteriaceae occur as commensals or pathogens in humans. The increasing prevalence of multidrug-resistant bacteria has raised global concern. Following the reclassification of Enterobacteriaceae species into the order Enterobacterales in 2016. However, no quantification method has been reported that is designed and validated in the context of the current order-level taxonomy of Enterobacterales. Therefore, we aimed to develop a novel reverse transcription quantitative PCR (RT-qPCR) system for the quantification of Enterobacterales based on 23S rRNA. The system was used to quantify Enterobacterales species, and its applicability was evaluated using fecal samples from 99 patients with gastrointestinal cancer and 10 healthy volunteers. Furthermore, we performed a proof-of-concept evaluation of its utility for rapid assessment of antimicrobial susceptibility in carbapenem-resistant Enterobacterales (CRE). The system exhibited high analytical sensitivity and enabled quantification of diverse Enterobacterales spp., including newly classified species, with theoretical detection limits of 10³ cells/g feces and 1 cell/mL blood. In healthy volunteers, intestinal Enterobacterales were dominated by Escherichia coli and Enterobacter, whereas preoperative patients with gastrointestinal cancer exhibited greater diversity. In vitro, viable CRE cell counts determined by the RT-qPCR system 2 h after antibiotic treatment correlated well with culture-based susceptibility results obtained after 24 h, suggesting the feasibility of rapid antimicrobial susceptibility assessment within 6 h. The developed 23S rRNA RT-qPCR system provides a sensitive approach for quantifying Enterobacterales within the current taxonomic framework and may facilitate the rapid assessment of antimicrobial activity against CRE. CLINICAL TRIAL REGISTRATION: There is no clinical trial registration.</p>","PeriodicalId":18679,"journal":{"name":"Microbiology and Immunology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149182999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Issue Information – Cover","authors":"","doi":"10.1111/1348-0421.70097","DOIUrl":"https://doi.org/10.1111/1348-0421.70097","url":null,"abstract":"<p><b>Cover photograph</b>: Mitochondrial morphology analysis via confocal microscopy. HeLa cells transfected with control or pORF5-expressing vectors were marked with MitoTracker Red CMXRos (red) for mitochondrial staining and counterstained with DAPI (blue) for nuclei visualization, respectively. <i>Microbiol Immunol: 70:504-514</i>. Article link here\u0000 \u0000 <figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure></p>","PeriodicalId":18679,"journal":{"name":"Microbiology and Immunology","volume":"70 10","pages":"i-ii"},"PeriodicalIF":1.6,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/1348-0421.70097","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149100276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genome Analysis of Corynebacterium ulcerans Isolates Chronologically Recovered From the Same Cat for Two Years: Circulation in a Cat Shelter","authors":"Ryoko Jikihara,&nbsp;Miyuki Kimura,&nbsp;Hyun Kim,&nbsp;Tsuyoshi Sekizuka,&nbsp;Masatomo Morita,&nbsp;Makoto Kuroda,&nbsp;Akihiko Yamamoto,&nbsp;Mitsutoshi Senoh,&nbsp;Masaaki Iwaki","doi":"10.1111/1348-0421.70083","DOIUrl":"10.1111/1348-0421.70083","url":null,"abstract":"<p>Toxigenic <i>Corynebacterium ulcerans</i>, a zoonotic pathogen, was isolated repeatedly from a cat in an in-house group in Japan. Although the cat was cured once by antibiotic treatment, clonal isolates of the original pathogenic strain were recovered repeatedly during a 2-year course. Clonal isolates of those isolates were also obtained from other asymptomatic cats in the same shelter, suggesting that environmental circulation of the pathogen had occurred. Care should be taken to monitor and cure the animals if any of their groupmates test positive for the pathogen, even if asymptomatic.</p>","PeriodicalId":18679,"journal":{"name":"Microbiology and Immunology","volume":"70 10","pages":"525-531"},"PeriodicalIF":1.6,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/1348-0421.70083","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148579404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Repurposing Host Defense and Microbial Metabolism for Salmonella Gut Colonization","authors":"Tsuyoshi Miki,&nbsp;Takeshi Haneda,&nbsp;Masahiro Ito,&nbsp;Nobuhiko Okada,&nbsp;Yun-Gi Kim","doi":"10.1111/1348-0421.70084","DOIUrl":"10.1111/1348-0421.70084","url":null,"abstract":"<div>\u0000 \u0000 <p><i>Salmonella enterica</i> serovar Typhimurium (<i>S</i>Tm) is a leading cause of diarrheal disease and efficiently colonizes the gut lumen despite microbiota-mediated colonization resistance. Emerging evidence indicates that <i>S</i>Tm does not simply evade or overcome these barriers, but instead exploits host immune responses and microbiota-derived metabolic activities to create a permissive intestinal niche. In this review, we discuss recent advances in our understanding of <i>S</i>Tm gut colonization, with a focus on how host antimicrobial factors and microbiota-derived metabolites are repurposed to promote pathogen growth, motility, and invasion. We highlight findings showing that the antimicrobial lectin RegIIIβ, together with microbiota-dependent metabolites such as fatty acid-derived cues and polyamines, can unexpectedly facilitate <i>S</i>Tm colonization. Together, these studies support a model in which host defense programs and microbial metabolism are redirected to promote pathogen fitness, revealing potential therapeutic opportunities for controlling enteric infections.</p>\u0000 </div>","PeriodicalId":18679,"journal":{"name":"Microbiology and Immunology","volume":"70 10","pages":"481-492"},"PeriodicalIF":1.6,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148630910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mycobacterium intracellulare M.i.198—A Promising Strain for Studying Pathogenesis of Nontuberculous Mycobacterial Pulmonary Disease (NTM-PD)","authors":"Yoshitaka Tateishi,&nbsp;Ryoji Maekura,&nbsp;Yukiko Nishiuchi,&nbsp;Sohkichi Matsumoto","doi":"10.1111/1348-0421.70081","DOIUrl":"10.1111/1348-0421.70081","url":null,"abstract":"<p>In this review, we introduce a promising strain for studying pathogenesis of nontuberculous mycobacterial pulmonary disease (NTM-PD), <i>Mycobacterium intracellulare</i> M.i.198. M.i.198 was isolated from a patient with progressive <i>Mycobacterium avium-intracellulare</i> complex pulmonary disease (MAC-PD) in whom surgical operation was required to suppress disease progression. M.i.198 shows progressive illness in infected mice in terms of bacterial load, inflammation, and by high-dose inoculation, mortality as well. Although M.i.198 is resistant to clarithromycin, the pathogenicity of M.i.198 in mice indicates the high potency for use to evaluate drug efficacies in vivo. Furthermore, M.i.198 can be genetically manipulated, which is quite different from other MAC strains, especially those of <i>M. avium</i> subsp. <i>hominissuis</i>. We herein report the bacteriological findings, experimental virulence and functional genomic features of M.i.198 with a small review of MAC strains used for animal models of MAC-PD.</p>","PeriodicalId":18679,"journal":{"name":"Microbiology and Immunology","volume":"70 10","pages":"493-503"},"PeriodicalIF":1.6,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/1348-0421.70081","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148592724","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Levilactobacillus Brevis NZ3 Isolated From Fermented Brassica Rapa L. Induces IL-15 Production in Dendritic Cells via Inducing IFN-α","authors":"Akihiro Masaki,&nbsp;Fumie Niitsuma,&nbsp;Hiroka Sasahara,&nbsp;Katsunori Endo,&nbsp;Sachi Tanaka","doi":"10.1111/1348-0421.70080","DOIUrl":"10.1111/1348-0421.70080","url":null,"abstract":"<div>\u0000 \u0000 <p>Interleukin-15 (IL-15) is a potential adjuvant in the activation of antitumor and antiviral immunity. Certain fermented food components possess immunomodulatory effects. We previously showed that lactic acid bacteria (LAB) isolated from Nozawana-zuke—the traditional Japanese fermented <i>Brassica rapa</i> L. pickle—activate immune function. Here we aimed to identify the LAB strain in fermented <i>B. rapa</i> L. that can markedly induce the expression of IL-15 mRNA in dendritic cells (DCs). We found that the <i>Levilactobacillus brevis</i> NZ3 strain isolated from <i>B. rapa</i> L. induces IL-15 production in DCs. We also provided mechanistic insight into the mechanism by which the NZ3 strain induces IL-15 production in DCs. We report that the NZ3 strain-induced IL-15 production in DCs is mediated by Toll-like receptor 3 signaling. Furthermore, inhibiting the interferon-α/β receptor alpha chain abrogated the NZ3 strain-induced IL-15 production. Further analysis using a Protein Kinase B (AKT) inhibitor revealed that the NZ3 strain-induced IL-15 production is mediated by AKT signaling, which occurs downstream of Interferon-α/β receptor signaling. Overall, our results indicate that the <i>Levilactobacillus brevis</i> NZ3 strain may serve as a potentially beneficial immunomodulatory bacterial strain. Moreover, due to its ability to induce IL-15 production, the NZ3 strain may serve as a candidate immunomodulatory strain for future studies.</p>\u0000 </div>","PeriodicalId":18679,"journal":{"name":"Microbiology and Immunology","volume":"70 10","pages":"515-524"},"PeriodicalIF":1.6,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148471806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chlamydia trachomatis Plasmid-Encoded Protein pORF5 Induces Mitochondrial Fission by Activating Drp1 via the MAPK/ERK Signaling Pathway","authors":"Yan Zou,&nbsp;Silu Gong,&nbsp;Liuliang Guo,&nbsp;Boru Tang,&nbsp;Jun Zhang","doi":"10.1111/1348-0421.70082","DOIUrl":"10.1111/1348-0421.70082","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 <p><i>Chlamydia trachomatis (C. trachomatis)</i> is a strictly parasitic pathogen that heavily relies on host cells for generating energy, acquiring nutrients, and evading immune responses. Mitochondrial dynamics—the balance of fusion and fission—are integral to cellular functions, including the maintenance of homeostasis, the regulation of metabolic processes, and the modulation of host innate immune pathways. Accordingly, <i>C. trachomatis</i> can specifically change the host mitochondrial dynamics to promote its intracellular replication. Mitochondrial fragmentation has been observed during the later phases of <i>C. trachomatis</i> infection; Nevertheless, the exact mechanisms remain poorly defined. The research aimed to determine the effect of the <i>C. trachomatis</i> secretory protein pORF5 in this process. In stable pORF5-expressing Hela cells, we employed confocal microscopy to analyze mitochondrial morphology and Western blotting to measure the expression of key mitochondrial dynamics proteins. Finally, immunofluorescence was used to monitor Drp1 mitochondrial translocation, and the effects of a pathway inhibitor on mitochondrial fission were evaluated. We observed that the plasmid-encoded protein pORF5 can induce mitochondrial fission. Mechanistically, this process is dependent on the activation of the ERK/Drp1 signaling axis, which indicates the crucial importance of this pathway and its effect on pORF5-induced mitochondrial fragmentation.</p>\u0000 </section>\u0000 </div>","PeriodicalId":18679,"journal":{"name":"Microbiology and Immunology","volume":"70 10","pages":"504-514"},"PeriodicalIF":1.6,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148549792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bordetella parapertussis Evades Neutrophil-Mediated Killing by Failing to Trigger Innate Activation Even After IFN-γ Priming.","authors":"Carlos Manuel Baroli, Juan Pablo Gorgojo, Mariela Del Carmen Carrica, Maria Eugenia Rodriguez","doi":"10.1111/1348-0421.70094","DOIUrl":"https://doi.org/10.1111/1348-0421.70094","url":null,"abstract":"<p><p>B. parapertussis is one of the etiologic agents of whooping cough and its incidence has increased following the COVID-19 pandemic. Since current pertussis vaccines fail to induce protection against B. parapertussis, the course of infection critically relies on the innate immune response. However, in the absence of opsonic antibodies, B. parapertussis fails to activate resting neutrophils, thereby preventing bactericidal responses. We here investigated whether neutrophil priming with gamma-interferon (IFN-γ), the main proinflammatory cytokine present during infection, changes this outcome. We observed that IFN-γ- priming of neutrophils did not enhance extracellular nor intracellular bactericidal mechanisms against B. parapertussis. Human neutrophils remain basically unresponsive to this pathogen despite IFN-γ priming, and this lack of activation proved independent of adenylate cyclase toxin (CyaA), the immunomodulatory toxin produced by B. parapertussis. Collectively, our findings demonstrate that B. parapertussis does not trigger neutrophil activation, irrespective of the inflammatory context. This ability to evade a key arm of the innate immune response likely constitutes a critical pathogenic trait that, particularly in the absence of cross-protection conferred by current pertussis vaccines, underlies persistent infections and the continued circulation of the pathogen.</p>","PeriodicalId":18679,"journal":{"name":"Microbiology and Immunology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149111825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification of Bacitracin Resistance Mechanisms in Streptococcus sobrinus.","authors":"Takuya Arita, Miki Kawada-Matsuo, Saki Nishihama, Bingxin Song, Yumi Yamauchi, Kosuke Ueda, Manami Tsunoi, Junzo Hisatsune, Katsuhiro Takeda, Motoyuki Sugai, Hideki Shiba, Hitoshi Komatsuzawa","doi":"10.1111/1348-0421.70092","DOIUrl":"https://doi.org/10.1111/1348-0421.70092","url":null,"abstract":"<p><p>Streptococcus sobrinus is a member of the Streptococcus mutans group and is a cariogenic bacterium similar to S. mutans. One of the characteristics of these bacteria is bacitracin resistance, and BceAB (MbrAB), an ABC transporter of S. mutans, has been reported to be involved in bacitracin resistance. However, the factors responsible for bacitracin resistance in S. sobrinus are unknown. In this study, 11 S. sobrinus strains were isolated from the oral cavity, and their bacitracin susceptibility was assessed. The results showed that 9 strains were low-susceptible to bacitracin (MIC = 128-512 µg/mL), whereas 2 strains were highly susceptible (MIC = 32 µg/mL). Whole-genome analysis of all strains identified genes encoding an ABC transporter (designated as BceAB) and its adjacent two-component system (BceRS), which showed high homology with the BceAB-BceRS locus in S. mutans. We successfully generated bceAB-deletion strains from bacitracin-low-susceptibility strains (HSB4 and HSB10) and a bacitracin-high-susceptibility strain (HSB8). Upon verifying their bacitracin susceptibility, the deletion strains derived from the bacitracin-low-susceptibility strains exhibited increased susceptibility compared to the wild-type strains, whereas the deletion strain of HSB8 showed no change in susceptibility. Quantitative RT-PCR revealed that, in the low-susceptibility HSB5 strain, bacitracin induced bceAB expression in a dose-dependent manner, whereas no such induction was observed in the high-susceptibility HSB7 strain. Comparison of the amino acid sequences of the BceAB-BceRS region among representative clinical isolates revealed that only BceS contained a mutation at the 179th amino acid residue (E179K) specific to the bacitracin-high-susceptibility strain. Based on these results, BceAB was concluded to be an intrinsic factor for bacitracin resistance, and BceRS may be associated with bacitracin-induced expression of BceAB in S. sobrinus.</p>","PeriodicalId":18679,"journal":{"name":"Microbiology and Immunology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149111838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Age-Associated Antimicrobial Resistance in Escherichia coli Isolates From Companion Dogs and Cats Linked to CTX-M Gene Carriage.","authors":"Kai Kobayashi, Hiroaki Kubota, Tsukasa Ariyoshi, Kohji Mori, Yoshitsugu Ochiai, Kenji Sadamasu, Takashi Chiba","doi":"10.1111/1348-0421.70095","DOIUrl":"https://doi.org/10.1111/1348-0421.70095","url":null,"abstract":"<p><p>As companion animals live in close contact with humans, the presence of antimicrobial-resistant organisms in these animals is an important issue in veterinary medicine from a One Health perspective. In this study, we isolated a total of 385 Escherichia coli strains from fecal samples collected from 218 companion dogs and 167 companion cats that visited veterinary clinics in Tokyo, Japan, from 2021 to 2024. Antimicrobial resistance to third-generation cephalosporins and fluoroquinolones increased significantly with host age, even though fecal abnormalities were low relevance. A total of 60 isolates were resistant to at least one third-generation cephalosporin, and whole-genome analysis was performed to further characterize these isolates. The isolates were classified as CTX-M gene-carrying or AmpC-associated isolates, including those carrying acquired AmpC genes and those harboring chromosomal ampC promoter mutations. The age-associated increase was more pronounced among CTX-M gene-carrying isolates than among AmpC-associated isolates. CTX-M gene-carrying isolates frequently exhibited concurrent levofloxacin resistance and were predominantly represented by ST131. Core-genome multilocus sequence typing revealed that these CTX-M gene-carrying isolates were phylogenetically similar to previously reported isolates of both human and animal origin. These findings suggest that the age-associated increase in resistance is related to the expansion of specific CTX-M gene-carrying lineages rather than to a uniform increase across all cephalosporin-resistance mechanisms. Our results support the need for continuous investigation within a One Health framework and further epidemiological and genomic surveillance.</p>","PeriodicalId":18679,"journal":{"name":"Microbiology and Immunology","volume":" ","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149111835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}