Gardnerella vaginalis small colony variants

项目总结 细菌性阴道病(BV)是育龄妇女最常见的妇科疾病， 与不良妊娠结局和性传播疾病的增加有关。 阴道加德纳氏菌是与BV相关的标志性细菌物种，但其感染机制 和坚持不懈并没有得到很好的理解。此外，阴道毛滴虫感染复发的机制 目前尚不清楚抗生素治疗后的效果。我们发现阴道毛滴虫有两种不同的生长形式， 一种生长缓慢的小菌落变体(SCV)和一种生长较快的大菌落变体(LCV)。SCV表单 产生更多的毒素阴道溶血素，对抗生素更具抗药性，对细菌的生长更具抑制作用 乳杆菌属LCV能产生更多的生物膜，对奈瑟菌的生长有更强的抑制作用 淋病。初步的蛋白质组学分析表明，SCV下调DNA复制和蛋白质 合成和上调阴道溶血素和其他可能的毒力因子。我们假设SCV是一个 为引发感染或在不利条件下持续存在而准备的细菌的形式，而LCV 提供更快的增殖并建立支持多种BV相关病原体的生物膜。为了这些 研究中，我们将表征SCV感染能力的差异，并使突变株表征 该变异株毒力增强和代谢改变的关键因素。发病机制 研究将包括器官培养中人类宫颈组织的感染。我们将确定涉及以下方面的机制 使用蛋白质组学和抗生素耐药性测量在不利条件下的持久性和存活率， 我们将确定刺激相变的因素。

PROJECT SUMMARY Bacterial vaginosis (BV) is the most common gynecological disorder in women of childbearing age and is associated with adverse pregnancy outcomes and enhanced transmission of sexually-transmitted diseases. Gardnerella vaginalis is the signature bacterial species associated with BV, but its mechanisms of infection and persistence are not well understood. Furthermore, the mechanisms by which G. vaginalis infection recurs after antibiotic treatment are not known. We have discovered that G. vaginalis grows in two different forms, as a slow-growing small colony variant (SCV) and as a faster-growing large colony variant (LCV). The SCV form produces more of the toxin vaginolysin, is more antibiotic resistant, and is more inhibitory to the growth of Lactobacillus spp. The LCV produces more biofilms and is more inhibitory to the growth of Neisseria gonorrhoeae. Preliminary proteomic analyses indicate that SCVs downregulate DNA replication and protein synthesis and upregulate vaginolysin and other putative virulence factors. We hypothesize that the SCV is a form of the bacteria primed for initiating infection or for persisting under adverse conditions, while the LCV gives faster multiplication and builds the biofilm that supports multiple BV-associated pathogens. For these studies, we will characterize differences in infection abilities of the SCVs and make mutants to characterize the key factors involved in the increased virulence and altered metabolism of the variant form. Pathogenesis studies will include infection of human cervical tissue in organ culture. We will identify mechanisms involved in persistence and survival in adverse conditions using proteomics and measurements of antibiotic resistance, and we will identify factors stimulating phase variation.