Small molecule inhibitors of bacterial secretion system

本申请描述了一个为期两年的研究学者发展计划，以确定和描述 铜绿假单胞菌III型分泌系统的小分子抑制剂。长期目标是 建立高效和资金充足的研究项目，研究细菌病原体和细菌之间的相互作用 利用本提案中概述的抑制剂的宿主细胞。铜绿假单胞菌是一种机会性病原体， 革兰氏阴性菌医院感染的主要原因。导致这种病毒毒性的一个因素 细菌是III型分泌系统。III型分泌系统是由20多种蛋白质组成的复合体， 允许将称为效应器分子的蛋白质直接从细菌细胞质输送到 真核宿主的细胞质。铜绿假单胞菌产生两种高度细胞毒性效应分子EXOS和 ExoU。这种毒素传递机制在许多细菌病原体中都是相同的，包括耶尔森氏菌， 沙门氏菌、志贺氏菌、致病性大肠杆菌、衣原体和许多其他细菌。这一现象的流行 保守系统提示，III型分泌物是预防感染的理想靶点。 细菌病原体。这项提议旨在通过高通量检测来鉴定小分子抑制剂 宿主细胞对铜绿假单胞菌感染的保护措施。保护性化合物将按以下方式分类 III型注射途径中的抑制步骤。与原始保护性化合物相关的分子 将有助于识别出更有效的抑制剂。I型纤溶酶抑制剂的生物学特异性 注射途径将在其他利用III型分泌系统的病原体中进行测试。此外，a 抑制物和III型分泌物成分之间的直接联系将通过基因鉴定来确定 每类抑制剂的靶标。该方案中生成的工具可用于剖析生物步骤 在利用III型分泌物建立的许多细菌病原体之间共享或不同的 感染。此外，本提案中确定的小分子抑制剂可以作为一个开始 发展抑制革兰阴性杆菌感染的治疗药物的要点 它们利用了第三类分离。

This application describes a two-year research scholar development program to identify and characterize small molecular inhibitors of Pseudomonas aeruginosa type III secretion system. The long term goal is to establish a highly productive and well funded research program in the interaction of bacterial pathogens and host cells utilizing the inhibitors outlined in this proposal. P. aeruginosa is an opportunistic pathogen that is the leading cause of Gram-negative nosocomial infections. One factor that contributes to the virulence of this bacteria is the type III secretion system. Type III secretion system is a complex of over twenty proteins that allows for delivery of proteins called effector molecules directly from the bacterial cytoplasm into the cytoplasm of the eukaryotic host. P. aeruginosa delivers two highly cytotoxic effector molecules, ExoS and ExoU. This mechanism of toxin delivery is shared among many bacterial pathogens including Yersinia, Salmonella, Shigella, enteropathogenic E. coli, Chlamydia and many others. The prevalence of this conserved system suggests that type III secretion is an ideal target for inhibition to prevent infection by these bacterial pathogens. This proposal aims to identify small molecular inhibitors by a high-throughput assay that measures protection of host cells to infection by P. aeruginosa. Protective compounds will be classified by the inhibitory step in the type III injection pathway. Related molecules to the original protective compounds will allow identification of more potent inhibitors. The biological specificity of the inhibitors on the type III injection pathway will be tested in other pathogens that utilize type III secretion systems. Furthermore, a direct link between the inhibitor and type III secretion component will be made by identification of the genetic target of each class of inhibitors. The tools generated in this proposal can be used to dissect biological steps that are shared or distinct between a number of bacterial pathogens that utilize type III secretion to establish infections. Furthermore, the small molecule inhibitors identified in this proposal may be used as a starting point for the development of theraputics to inhibit bacterial infection caused by Gram-negative pathogens that utilize type III seceretion.