C. jejuni CDT Subunit Interactions

C. jejuni CDT 亚基相互作用

• 批准号: 6777399
• 负责人: CAROL L PICKETT
• 金额: $ 33.09万
• 依托单位: UNIVERSITY OF KENTUCKY
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-30 至 2005-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6777399
• 关键词: Campylobacter; Guillain Barre syndrome; bacterial cytopathogenic effect; bacterial genetics; bacterial proteins; cell surface receptors; diarrhea; exotoxins; genetic manipulation; host organism interaction; protein structure; protein structure function; tissue /cell culture

DESCRIPTION (provided by applicant): Campylobacter jejuni is currently one of the most common bacterial causes of diarrheal disease in humans in the United States. It has also been strongly implicated as one of the most common infections to precede the development of Guillian-Barre' syndrome, an autoimmune disease. The study of C. jejuni pathogenesis has identified few potential virulence factors. One of these is the exotoxin, cytolethal distending toxin, (CDT). Recent work has identified that the C. jejuni CDT is a member of a new family of toxins that can cause a G2 cell cycle block in certain mammalian cultured cells via direct DNA damage and invocation of the DNA damage checkpoint pathway. However, little is known about the specific interactions of the CDT subunits, CdtA, CdtB, and CdtC, with sensitive cells. Nor is much known about CDT subunit interactions within the CDT holotoxin. This information will be crucial for gaining an understanding of how to best develop vaccine strategies and interventions in diseases caused by bacteria that produce CDT. The broad, long-term goals of this proposal are to understand how CDT interacts with sensitive cells. In particular, we will determine the nature of the Cdt subunit interactions with the surface of sensitive cells, and explore the nature and extent to which the Cdt subunits interact with each other. These studies are central to our understanding of how CDT affects mammalian cells. The specific aims of the proposal are to test the hypothesis that the individual Cdt proteins have specific capabilities involved in recognizing a specific mammalian cell surface receptor, and in interacting with each other to form an effective holotoxin. In Aim 1, a variety of mutations will be made in each of the Cdt subunits. The effects of the mutations on toxicity, holotoxin assembly, and cell binding will be tested. In Aim 2, two different approaches will be used to identify areas within the Cdt proteins that are responsible for mediating the association of the subunits into holotoxin. In Aim 3, we propose to characterize and identify the CDT cell surface receptor. These studies should substantially increase our knowledge of CDT biology and allow for the development of new treatment and prevention strategies.

描述（由申请人提供）：空肠弯曲杆菌目前是美国人类腹泻病最常见的细菌原因之一。它也被强烈认为是在吉利安-巴利综合征（一种自身免疫性疾病）发生之前最常见的感染之一。空肠弯曲菌发病机制的研究已经确定了一些潜在的毒力因子。其中之一是外毒素、细胞致死膨胀毒素（CDT）。最近的研究表明，空肠弯曲菌 CDT 是一个新毒素家族的成员，该毒素可通过直接 DNA 损伤和调用 DNA 损伤检查点途径，在某些哺乳动物培养细胞中引起 G2 细胞周期阻断。然而，人们对 CDT 亚基、CdtA、CdtB 和 CdtC 与敏感细胞的特异性相互作用知之甚少。关于 CDT 全毒素内 CDT 亚基的相互作用也知之甚少。这些信息对于了解如何最好地制定针对产生 CDT 的细菌引起的疾病的疫苗策略和干预措施至关重要。该提案的广泛、长期目标是了解 CDT 如何与敏感细胞相互作用。特别是，我们将确定Cdt亚基与敏感细胞表面相互作用的性质，并探索Cdt亚基彼此相互作用的性质和程度。这些研究对于我们了解 CDT 如何影响哺乳动物细胞至关重要。 该提案的具体目的是检验以下假设：单个 Cdt 蛋白具有识别特定哺乳动物细胞表面受体的特定能力，并相互相互作用形成有效的全毒素。在目标 1 中，每个 Cdt 亚基都会发生多种突变。将测试突变对毒性、全毒素组装和细胞结合的影响。在目标 2 中，将使用两种不同的方法来识别 Cdt 蛋白内负责介导亚基与全毒素关联的区域。在目标 3 中，我们建议表征和鉴定 CDT 细胞表面受体。这些研究将大大增加我们对 CDT 生物学的了解，并有助于开发新的治疗和预防策略。