Characterization of a novel family of Small Regulatory Proteins modulating virulence in Enterobacteriaceae

项目摘要/摘要 在美国，疾病控制和预防中心(CDC)估计有200多人 每年发生100万起急性胃肠炎，导致近100万人住院治疗，超过 5000人死亡。无法获得针对肠道病原体的疫苗，部分原因是对 肠道病原体进化为定居、繁殖和逃避宿主的许多毒力机制 防御。我们最近发现了ANR(AraC负向调节因子)家族，它由一个大的 包括弧菌在内的各种具有临床重要性的肠道病原体产生的小调节蛋白的数量 、沙门氏菌属、志贺氏菌属、耶尔森氏菌属、柠檬酸杆菌属、肠毒素(ETEC)属、致病性肠杆菌属 肠出血性大肠埃希菌(EHEC)和肠聚集性大肠杆菌(EAEC)。ANR家族的成员 调节毒力因子的表达，如菌毛、毒素、3型和6型分泌系统， 以及与新陈代谢、压力反应和健康相关的基因，通过蛋白质-蛋白质相互作用 AraC/XylS家族的正转录调控因子和HNS家族的负调控因子。 此外，这种调控系统的缺失影响了自然模型中细菌的致病作用。 感染。我们的总体假设是，ANR家族在协调调节健康方面起着关键作用 通过同时控制AraC和HNS对肠杆菌科病原体的毒力和毒力 全球监管机构。在这里，我们建议获得对ANR分子相互作用的机械性见解(AIM-1)， 以EAEC、EPEC和轮状念珠菌为致病模型的调控(AIM 2)和致病(AIM-3)， 人类干细胞技术和疾病的自然动物模型，再加上遗传、生化和 表面等离子体共振(SPR)、时移荧光显微镜等分子技术 (TLFM)和芯片序列我们提出的研究将促进我们对全球基因调控的了解 控制致病菌适合性和毒性的机制，并可能开辟新的途径 治疗性干预。

PROJECT SUMMARY/ABSTRACT In the United States, the Center for Disease Control and Prevention (CDC) has estimated that more than 200 million episodes of acute gastroenteritis occur annually, resulting in nearly 1 million hospitalizations and over 5000 deceases. Vaccines against enteric pathogens are not available due, in part, to limited knowledge of the many virulence mechanisms that enteropathogens have evolved to colonize, multiply and escape host defenses. We have recently discovered the ANR (AraC Negative Regulators) family, comprising a large number of small regulatory proteins produced by diverse clinically important enteric pathogens including Vibrio spp., Salmonella spp., Shigella spp., Yersinia spp., Citrobacter spp., enterotoxigenic (ETEC), enteropathogenic EPEC, enterohaemorragic (EHEC) and enteroaggregative E. coli (EAEC). Members of the ANR family modulate the expression of virulence factors such as fimbriae, toxins, type-3 and type-6 secretion systems, and genes associated with metabolism, stress-response and fitness, by protein-protein interactions with positive transcriptional regulators of the AraC/XylS family and negative regulators of the HNS family. Furthermore, the absence of this regulatory system affects bacterial pathogenesis in a natural model of infection. Our overall hypothesis is that the ANR family plays a critical role in the concerted regulation of fitness and virulence in pathogens of the Enterobacteriaceae family by taking concomitant control of AraC and HNS global regulators. Here, we propose to obtain mechanistic insights into ANR molecular interactions (AIM-1), regulation (AIM 2) and pathogenesis (AIM-3) using EAEC, EPEC and C. rodentium as pathogen models, human stem cell technology and a natural animal model of disease, coupled with genetic, biochemical and molecular approaches such as Surface Plasmon Resonance (SPR), Time-lapse fluorescence microscopy (TLFM) and ChIP-seq. Our proposed studies will advance our knowledge of global gene regulatory mechanisms that govern fitness and virulence in pathogenic bacteria, and will likely open new avenues for therapeutic intervention.