Genetic Mechanisms of Sporulation Induction in C. difficile

项目总结/摘要 艰难梭菌（Clostridioides difficile）（以前称为梭菌属）是引起严重腹泻的主要院内病原体 传染性强且难以治疗的疾病。艰难梭菌由于形成而容易传播， 从被感染的宿主身上排出有传染性的孢子。C.艰难梭菌对大多数消毒剂有抵抗力 并且对于细菌在宿主肠外的存活至关重要。胃肠道是唯一 已知的自然环境支持C。很难形成孢子，但我们对孢子如何形成知之甚少。 形成是由细菌引发的。这个项目的长期目标是揭示 控制C.艰难孢子形成。根据我们的数据，我们假设， 早期孢子形成蛋白在独立的途径中起作用，通过控制 激活主转录调节因子Spo 0A。本申请的具体目标是定义 作用于Spo 0A的直接调节机制，并描绘控制Spo 0A的分子途径。 孢子形成起始利用我们以前在C语言中的经验。艰难的分子遗传学，基因调控， 和革兰氏阳性肠致病，我们将通过两个详细的实验来满足目标 具体目标。在目标1中，我们将扩展我们目前的研究，使用 遗传学和生物化学方法的结合与此同时，目标2扩展了上位分析， Spo 0A调节途径，随后对起始级联中的蛋白质进行功能分析。这 研究是创新的，因为它结合了生物分子和遗传方法来解决一个基本的问题。 这一重要而复杂的生物学过程。这些目标的完成预计将使 孢子启动的潜在漏洞这项工作是制定合理战略的必要步骤 阻碍C.通过阻止感染性孢子在宿主体内的形成而难以传播。

Project Summary/Abstract Clostridioides difficile (formerly Clostridium) is a major nosocomial pathogen that causes severe diarrheal disease that is highly infectious and difficult to treat. C. difficile is easily transmitted due to the formation and expulsion of contagious spores from infected hosts. The spore form of C. difficile is resistant to most disinfectants and is critical for the survival of the bacterium outside of the host intestine. The gastrointestinal tract is the only natural environment known to support C. difficile spore formation, but we understand little about how spore formation is initiated by the bacterium. The long-term goal of this project is to uncover the molecular mechanisms that control the initiation of C. difficile sporulation. Based on our data, we hypothesize that several early sporulation proteins function in independent pathways to regulate the initiation of sporulation by controlling activation of the master transcriptional regulator, Spo0A. The specific objectives of this application are to define the direct regulatory mechanisms that act upon Spo0A and to delineate the molecular pathways that control sporulation initiation. Capitalizing on our previous experiences in C. difficile molecular genetics, gene regulation, and Gram-positive intestinal pathogenesis, we will meet the objectives through the experiments detailed in two specific aims. In Aim 1, we will extend our current studies to uncover direct interacting partners of Spo0A using a combination of genetic and biochemical approaches. In parallel, Aim 2 expands epistatic analyses to construct Spo0A regulatory pathways, followed by functional analyses of the proteins within the initiation cascade. This research is innovative because it combines biomolecular and genetic approaches to resolve a fundamental question about this important and complex biological process. Completion of these aims is expected to expose potential vulnerabilities in spore initiation. This work is an essential step in the development of rational strategies to impede C. difficile transmission by preventing the formation of infectious spores in the host.