mSphere最新文献

{"title":"The potential of biogas production and effects of alfalfa silage under the synergistic influence of <i>Lactobacillus acidophilus</i> and <i>Rosa roxburghii</i> pomace waste on the fermentation quality and bacterial community.","authors":"Maoya Li, Jiachuhan Wang, Qiming Cheng, Zhongfu Long, Chao Chen, Yixiao Xie, Yao Lei, Yulian Chen, Yuanyuan Zhao, Xiangjiang He, Wei Yan, Zhijun Wang","doi":"10.1128/msphere.01054-24","DOIUrl":"10.1128/msphere.01054-24","url":null,"abstract":"<p><p>The process of ensiling serves as a dual-purpose technique, functioning as a means of preserving biomass for biogas production while serving as a biological pretreatment method with the potential for little fermentation loss. In this study, we investigate the potential of <i>Rosa roxburghii</i> pomace (RP) and <i>Lactobacillus acidophilus</i> to improve the biomass preservation of biogas produced from alfalfa during anaerobic storage. Coinoculation of RP and <i>Lactobacillus acidophilus</i> resulted in better preservation of nutrients (biomass), with a significant increase of 47.38% within the lactic acid content and a notable decline of 40.34% in the ammonia nitrogen content relative to those in the control treatment. Moreover, coinoculation of RP and <i>Lactobacillus acidophilus</i> resulted in an elevated proportion of <i>Lactobacillus,</i> and the species <i>Lactiplantibacillus plantarum</i> dominated anaerobic fermentation. The synergistic effect of RP and <i>Lactobacillus acidophilus</i> continuously stimulated anaerobic fermentation, leading to 33.33% and 23.17% increases in methane production and acetate content, respectively, after 72 h of coinoculation with RP and <i>Lactobacillus acidophilus</i> compared to the control treatment. Overall, coinoculation of RP and <i>Lactobacillus acidophilus</i> offers an attractive opportunity to increase methane production from fruit waste while reducing costs and synergistically integrating with other pretreatment techniques to optimize the methane generation potential.</p><p><strong>Importance: </strong>Considering the increasing global energy demand and urgent environmental issues, exploring prospective resources for bioenergy production is imperative. However, the biomass of legume perennials may serve as an inexpensive and stable source of clean energy for modern society due to its wide availability and broad range of sources. In addition, the combination of RP and <i>Lactobacillus acidophilus</i> application increased the abundance of Lactobacillus, inhibited the growth of Kosakonia, and promoted anaerobic fermentation, which had beneficial synergistic effects on biomass retention and biogas production in alfalfa samples. Coinoculation improvements with RP and <i>Lactobacillus acidophilus</i> observed here are expected to reduce costs associated with CH₄ conversion bioprocesses and increase CH₄ production.</p>","PeriodicalId":19052,"journal":{"name":"mSphere","volume":" ","pages":"e0105424"},"PeriodicalIF":3.7,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12108078/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144025692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The ArcAB two-component system is associated with the susceptibility of <i>Aggregatibacter actinomycetemcomitans</i> to superoxide and hydrogen peroxide.","authors":"Mohammad Farid Ratman, Yuichi Oogai, Airi Matsumoto, Masanobu Nakata","doi":"10.1128/msphere.00019-25","DOIUrl":"10.1128/msphere.00019-25","url":null,"abstract":"<p><p><i>Aggregatibacter actinomycetemcomitans</i> is a Gram-negative facultative anaerobe and is associated with periodontal disease. This bacterium is exposed to environmental stresses, such as osmotic pressure, temperature shifts, pH shifts, and antimicrobial substances, including reactive oxygen species (ROS), in the human oral cavity. The bacterial two-component system ArcAB modulates gene expression in response to environmental changes, primarily by sensing oxygen pressure in several pathogens belonging to the γ-proteobacteria. It is also known to provide adaptation to ROS stress; however, its function in <i>A. actinomycetemcomitans</i> remains unclear. In this study, we found that the expression of <i>sod</i>, which encodes superoxide dismutase, was increased in the inactivated mutant of <i>arcA</i>, which encodes a response regulator. The mutant exhibited reduced susceptibility to superoxide and hydrogen peroxide (H₂O₂). Additionally, this strain showed reduced susceptibility to H₂O₂ from <i>Streptococcus sanguinis</i> and increased survival in macrophages. Since ArcB is the cognate histidine kinase of ArcA, the inactivated mutant of <i>arcB</i> was analyzed for its phenotypes. The <i>arcB</i> mutant exhibited reduced susceptibility to superoxide and H₂O₂. Compared to wild type, the phosphorylation level of ArcA in the <i>arcB</i> mutant was decreased. These results suggest that the ArcA response regulator receives phosphate groups from ArcB histidine kinase and negatively regulates the expression of <i>sod</i>, thereby affecting bacterial survival in response to ROS produced by oral commensals and host immune cells.IMPORTANCE<i>Aggregatibacter actinomycetemcomitans</i> is an oral pathogen that is known to be a highly virulent periodontal pathogen, showing strong adherence to periodontal tissue and toxin production, which leads to aggressive periodontitis. This bacterium is associated not only with oral infections but also with systemic infections, such as infective endocarditis and brain abscesses. Therefore, elucidating the adaptation mechanisms of this bacterium is important for human health. Bacterial two-component systems (TCSs) have been studied as attractive targets for elucidating bacterial fitness and pathogenicity in the host. This study characterized a TCS in <i>A. actinomycetemcomitans</i>, ArcAB, which is associated with susceptibility to ROS produced by host cells or oral commensals. Our findings provide insights into the bacterial adaptation mechanism against oxidative stress, which is crucial for understanding the survival strategies of the periodontal pathogen.</p>","PeriodicalId":19052,"journal":{"name":"mSphere","volume":" ","pages":"e0001925"},"PeriodicalIF":3.7,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12108069/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144012174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"When passion is not enough: the waning of the infectious disease workforce.","authors":"Jennifer A Leeds","doi":"10.1128/msphere.00902-24","DOIUrl":"10.1128/msphere.00902-24","url":null,"abstract":"<p><p>Scientists and physicians who pursue careers in infectious diseases are often passionate about understanding microbial pathogenesis and anti-microbial resistance. They are driven by the impact that their work has on improving public health and reducing human suffering through the discovery, development, and delivery of technologies that enable prevention and radical cure of debilitating and deadly diseases. Yet, despite their passion, there is a shrinking talent pool in antibiotic research and development (R&D) (https://www.amrindustryalliance.org/mediaroom/leaving-the-lab-tracking-the-decline-in-amr-rd-professionals/) as well as in the clinical practice specialty of infectious diseases as recognized by the Infectious Diseases Society of America (https://www.idsociety.org/news--publications-new/articles/2024/idsa-and-pids-statement-on-2024-id-fellowship-match/). This talent drain has wide repercussions beyond its impact on R&D and clinical practice and needs to be addressed from many angles to attract and retain new talent, to increase investment in and output from antibiotic R&D, and to mitigate the rising risk of the inability to deliver safe and efficacious solutions to patients in need.</p>","PeriodicalId":19052,"journal":{"name":"mSphere","volume":" ","pages":"e0090224"},"PeriodicalIF":3.7,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12108070/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144019840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"mRNA vaccine design using the proteome of <i>Theileria annulata</i> through immunoinformatics approaches.","authors":"Roohollah Fattahi, Behrooz Sadeghi Kalani","doi":"10.1128/msphere.00809-24","DOIUrl":"10.1128/msphere.00809-24","url":null,"abstract":"<p><p>Theileriosis exerts a substantial impact on ruminants, resulting in significant economic losses within the animal husbandry sector. The current vaccine, a live attenuated parasite, has several limitations that hinder effective disease control. This study utilized immunoinformatics to prioritize potential vaccine candidates and pointed to the design of a novel mRNA vaccine against <i>Theileria annulata</i> using <i>in silico</i> methods. Nine antigenic proteins were selected using various software, and their epitopes were identified through immunoinformatics tools. These epitopes were assessed for their biological traits and homology. Their presentation by major histocompatibility complex (MHC) cells and other immune cells was analyzed using molecular docking techniques. A multi-epitope protein was then modeled and optimized, followed by structural and stability analyses of the mRNA vaccine construct. Finally, the immune response to the new vaccine was simulated. The identified epitopes were localized within the antigen-binding sites of their respective MHC alleles. The newly formulated vaccine demonstrated stability, exhibited no toxicity, and showed non-allergenic characteristics. It effectively elicited responses from both the humoral and cellular immune systems. The findings suggest that the desired engineered mRNA vaccine paves the way for the development of the deterrence of theileriosis. This potential merits additional exploration through rigorous laboratory experiments and subsequent clinical trials.IMPORTANCEThis study presents a cutting-edge approach in vaccine design against bovine theileriosis, a devastating disease affecting cattle globally. By leveraging immunoinformatics methodologies, a novel mRNA vaccine candidate was tailored using computational analyzes of <i>Theileria annulata</i> proteins. Antigenic protein identification, epitope evaluation, and structural optimization of the multi-epitope mRNA vaccine are pivotal advancements in vaccine development. Using computational modeling tools to predict immune responses enhances the efficiency and accuracy of vaccine design, potentially revolutionizing preventive strategies against bovine theileriosis. This research not only demonstrates the potential of immunoinformatics in vaccine innovation but also sheds light on a promising avenue for combating a significant livestock health concern, offering hope for more effective and targeted veterinary interventions.</p>","PeriodicalId":19052,"journal":{"name":"mSphere","volume":" ","pages":"e0080924"},"PeriodicalIF":3.7,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12108079/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144036060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Virus species names have been standardized; virus names remain unchanged.","authors":"F Murilo Zerbini, Peter Simmonds, Evelien M Adriaenssens, Elliot J Lefkowitz, Hanna M Oksanen, Poliane Alfenas-Zerbini, Frank O Aylward, Juliana Freitas-Astúa, Holly R Hughes, Małgorzata Łobocka, Mart Krupovic, Jens H Kuhn, Arcady Mushegian, Judit J Penzes, Alejandro Reyes, David L Robertson, Simon Roux, Luisa Rubino, Sead Sabanadzovic, Donald B Smith, Nobuhiro Suzuki, Dann Turner, Koenraad Van Doorslaer, Arvind Varsani","doi":"10.1128/msphere.00020-25","DOIUrl":"10.1128/msphere.00020-25","url":null,"abstract":"<p><p>Virus taxonomy, comprising classification and nomenclature, is regulated by the International Committee on Taxonomy of Viruses (ICTV). Taxon names are standardized to facilitate recognition and communication, with defined suffixes for each rank (e.g., the names of orders, families, and genera end in <i>-virales</i>, -<i>viridae,</i> and <i>-virus</i>, respectively). However, until recently, a standard format for species names was lacking. In 2021, following extensive discussion and community consultation, the ICTV decided to adopt a standardized binomial (Linnaean) format for virus species names, consisting of the genus name followed by a \"freeform\" species epithet. Previously assigned virus species names that were non-compliant with the binomial format have been fully updated. In contrast to taxon names regulated by the ICTV, the names of viruses, or \"common\" names, such as yellow fever virus or human immunodeficiency virus, are not under the remit of the ICTV and have not been changed.</p>","PeriodicalId":19052,"journal":{"name":"mSphere","volume":" ","pages":"e0002025"},"PeriodicalIF":3.7,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12108072/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143995489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tolerance and heteroresistance to echinocandins in <i>Candida auris</i>: conceptual issues, clinical implications, and outstanding questions.","authors":"Erika Shor, David S Perlin, Dimitrios P Kontoyiannis","doi":"10.1128/msphere.00161-25","DOIUrl":"10.1128/msphere.00161-25","url":null,"abstract":"<p><p><i>Candida auris</i> is a significant public health threat due to its environmental persistence and multidrug resistance, with echinocandins being the preferred treatment. However, in addition to resistance, echinocandin tolerance and heteroresistance may contribute to treatment challenges. Echinocandin tolerance involves reduced drug-mediated killing, while heteroresistance is the ability of a small cell subset to grow at high drug concentrations. These phenomena may facilitate the emergence of full resistance and complicate clinical outcomes. The clinical significance of these mechanisms remains unclear, with limited data correlating them with treatment failures. Research is needed to understand their mechanisms and impact, develop streamlined and robust methods to detect them in clinical settings, and explore mitigation strategies. The pathogen's range of drug adaptations demands innovative approaches like spatial transcriptomics to dissect these complex responses and improve patient outcomes.</p>","PeriodicalId":19052,"journal":{"name":"mSphere","volume":" ","pages":"e0016125"},"PeriodicalIF":3.7,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12108057/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144036071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deletion of <i>RAP1</i> affects iron homeostasis, azole resistance, and virulence in <i>Candida albicans</i>.","authors":"Min-Chi Yang, Wei-Luen Huang, Hsuan-Yu Chen, Shin-Huey Lin, Yu-Shan Chang, Kuo-Yun Tseng, Hsiu-Jung Lo, I-Ching Wang, Chi-Jan Lin, Chung-Yu Lan","doi":"10.1128/msphere.00155-25","DOIUrl":"10.1128/msphere.00155-25","url":null,"abstract":"<p><p>Rap1 is a DNA-binding protein conserved from yeast to mammals for its role in telomeric maintenance. Here, to explore additional functions of <i>Candida albicans</i> Rap1, we performed RNA sequencing analysis. Experimental validations further showed that Rap1 plays a role in iron regulation, especially under low-iron conditions. Moreover, Rap1 was involved in iron acquisition and modulation of iron-related genes. Rap1 was found to be associated with fluconazole resistance in a low-iron condition. Finally, we demonstrated that the deletion of <i>RAP1</i> leads to reduced <i>C. albicans</i> virulence in a mouse model of infection. Together, this study reveals new functions of <i>C. albicans</i> Rap1, particularly in iron homeostasis, azole resistance, and virulence.</p><p><strong>Importance: </strong><i>Candida albicans</i> is an important pathogenic fungus that can cause superficial to life-threatening infections. Iron is essential for almost all organisms, yet it is highly restricted within the human host to defend against pathogens. To grow and survive in the iron-limited host environment, <i>C. albicans</i> has evolved multiple iron acquisition mechanisms. Understanding the regulation of iron homeostasis is, therefore, critical for elucidating <i>C. albicans</i> pathogenesis and virulence. This study explores the novel functions of <i>C. albicans</i> Rap1, with a focus on its contribution to iron acquisition and utilization. Our findings further highlight how iron availability impacts antifungal resistance and virulence through Rap1, providing insight into the complex iron regulatory machinery of <i>C. albicans</i>.</p>","PeriodicalId":19052,"journal":{"name":"mSphere","volume":" ","pages":"e0015525"},"PeriodicalIF":3.7,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12108065/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144009034","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Antibody-guided identification of <i>Achromobacter xylosoxidans</i> protein antigens in cystic fibrosis.","authors":"Cecilia Sahl, Sounak Chowdhury, Johan Malmström, Lisa I Påhlman","doi":"10.1128/msphere.00233-25","DOIUrl":"10.1128/msphere.00233-25","url":null,"abstract":"<p><p>Persistent bacterial airway infection is a hallmark feature of cystic fibrosis (CF). <i>Achromobacter</i> spp. are gram-negative rods that can cause persistent airway infection in people with CF (pwCF), but the knowledge of host immune responses to these bacteria is limited. The aim of this study was to investigate if patients develop antibodies against <i>Achromobacter xylosoxidans</i>, the most common <i>Achromobacter</i> species, and to identify the bacterial antigens that induce specific IgG responses. Seven serum samples from pwCF with <i>Achromobacter</i> infection were screened for antibodies against bacteria in an ELISA coated with <i>A. xylosoxidans</i>, <i>A. insuavis,</i> or <i>Pseudomonas aeruginosa</i>. Sera from pwCF with or without <i>P. aeruginosa</i> infection (<i>n</i> = 22 and 20, respectively) and healthy donors (<i>n</i> = 4) were included for comparison. Serum with high titers to <i>A. xylosoxidans</i> was selected for affinity purification of bacterial antigens using serum IgGs bound to protein G beads. The resulting IgG-antigen complexes were then analyzed using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Selected antigens of interest were produced in recombinant form and used in an ELISA to confirm the results. Four of the seven patients with <i>Achromobacter</i> infection had serum antibodies against <i>Achromobacter</i>. Using patient serum-IgG for affinity purification of <i>A. xylosoxidans</i> proteins, we identified eight antigens. Three of these, which were not targeted by anti-<i>P</i>. <i>aeruginosa</i> antibodies, were expressed recombinantly for further validation: dihydrolipoyl dehydrogenase (DLD), type I secretion C-terminal target domain-containing protein, and domain of uncharacterized function 336 (DUF336). While specific IgG against all three recombinant antigens was confirmed in the patient serum with high titers against <i>Achromobacter</i>, DLD and DUF336 showed the least binding to serum IgG from pwCF without <i>Achromobacter</i> spp. infection. Using serum IgG affinity purification in combination with LC-MS/MS and confirming the results using ELISA against recombinant proteins, we have identified bacterial antigens from <i>A. xylosoxidans</i>.IMPORTANCE<i>Achromobacter</i> species are opportunistic pathogens that can cause airway infections in people with cystic fibrosis. In this patient population, persistent <i>Achromobacter</i> infection is associated with low lung function, but the knowledge about bacterial interactions with the host is currently limited. In this study, we identify protein antigens that induce specific antibody responses in the host. The identified antigens may potentially be useful in serological assays, serving as a complement to culturing methods for the diagnosis and surveillance of <i>Achromobacter</i> infection.</p>","PeriodicalId":19052,"journal":{"name":"mSphere","volume":" ","pages":"e0023325"},"PeriodicalIF":3.7,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12108089/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144036006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of urolithin A on intracellular survival of <i>Mycobacterium tuberculosis</i> by regulating AKT-FOXO1-mediated autophagy.","authors":"Jing Bi, Li Song, Qinglong Guo, Xi Chen, Yaqi Gong, Haojia Wu, Fan Zhang, Jingbin Wang, Guoliang Zhang","doi":"10.1128/msphere.00061-25","DOIUrl":"10.1128/msphere.00061-25","url":null,"abstract":"<p><p>Tuberculosis (TB), resulting from <i>Mycobacterium tuberculosis</i> (Mtb), is one of the leading causes of morbidity and mortality in humans worldwide. Host-directed therapy (HDT) is a novel approach for treating TB, particularly those with drug resistance. Urolithin A (UroA) produced through bioconversion of plant-derived ellagic acid by gut microbes has been proven to have multiple beneficial effects in a variety of diseases without showing undesired adverse reactions. However, whether UroA has antimycobacterial effect and the underlying mechanism has not yet been reported. Here, we found that UroA significantly inhibited Mtb growth within both macrophages and mice. Moreover, UroA promoted the activation of autophagy in Mtb-infected macrophages via the protein kinase B-Forkhead box protein O1 signaling pathway, which contributed to the antimycobacterial effect of UroA. Additionally, UroA suppressed the survival of clinically isoniazid (INH)-resistant Mtb (C2) within macrophages, and the combination of UroA and INH synergistically enhanced host elimination of Mtb H37Rv. Therefore, UroA may be utilized as a potential candidate for HDT and as an adjunctive therapy with first-line anti-TB drugs.IMPORTANCEHost-directed therapy (HDT) is a novel approach for treating tuberculosis (TB), particularly those with drug resistance. Urolithin A (UroA) produced through bioconversion of plant-derived ellagic acid by gut microbes has been proven to have multiple beneficial effects in a variety of diseases without showing undesired adverse reactions. We found that UroA significantly inhibited <i>Mycobacterium tuberculosis</i> (Mtb) growth within macrophages. Moreover, UroA suppressed the survival of clinically isoniazid (INH)-resistant Mtb (C2) within macrophages, and the combination of UroA and INH synergistically enhanced host elimination of Mtb H37Rv. Therefore, UroA may be utilized as a potential candidate for HDT and as an adjunctive therapy with first-line anti-TB drugs.</p>","PeriodicalId":19052,"journal":{"name":"mSphere","volume":" ","pages":"e0006125"},"PeriodicalIF":3.7,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12108056/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144011800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 droplet digital PCR assay to measure pilin antigenic variation frequency in <i>Neisseria gonorrhoeae</i>.","authors":"Sarah J Quillin, Di Luo, Aoife Gavagan, Arthur Prindle, H Steven Seifert","doi":"10.1128/msphere.00094-25","DOIUrl":"10.1128/msphere.00094-25","url":null,"abstract":"<p><p>The strict human pathogen <i>Neisseria gonorrhoeae</i> (gonococcus [Gc]) infects an estimated 82 million individuals globally and is a World Health Organization-designated bacterial pathogen of public health importance due to escalating antimicrobial resistance. Gc vaccines have been hindered by Gc's ability to evade immune surveillance in part by varying its major surface antigens like the type IV pilus. We developed a quick and precise method for measuring pilin antigenic variation (Av) frequency using droplet digital PCR (ddPCR) technology. Two fluorescent probes were designed to detect either the hypervariable tail region of silent pilin locus <i>pilS</i>3-copy 1 (S3C1) or a sequence conserved in all <i>pilE</i> variants (CYS2). The appropriate frequency of pilin antigenic variation is measured by the proportion of <i>pilE</i> amplicons carrying the recombinant S3C1 copy relative to the total pilE amplicons measured by CYS2. The ddPCR assay is specific for RecA-dependent pilin antigenic variation. The reduced frequency of pilin Av in strains lacking RecA-modulating recombination protein RecX and the DNA helicase RecQ confirms the ability of the assay to measure changes in pilin Av frequency. We used the ddPCR assay to determine that pilin Av frequency is altered by the colony densities on a solid medium. The ddPCR assay is an accurate, efficient way to measure Gc pilin Av frequency.</p><p><strong>Importance: </strong>Gonorrhea is a sexually transmitted infectious disease of the human genital and nasopharyngeal mucosa caused by the host-restricted bacterium <i>Neisseria gonorrhoeae</i>. The rise of antibiotic-resistant gonorrhea is an urgent global threat to public health. Pilus antigenic variation is a gene conversion process that allows <i>N. gonorrhoeae</i> to evade host immune surveillance, and a mechanistic understanding of this process is crucial to understanding <i>N. gonorrhoeae</i> pathogenesis. This report shows that we can adopt a digital PCR methodology to quickly and accurately measure pilin antigenic variation.</p>","PeriodicalId":19052,"journal":{"name":"mSphere","volume":" ","pages":"e0009425"},"PeriodicalIF":3.7,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12108084/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143973016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}