Autotransporter proteins and virulence of Y. pestis

描述（由申请人提供）：鼠疫耶尔森氏菌是一种人类病原体，是鼠疫的病原体。不幸的是，由于鼠疫杆菌引起的高死亡率和严重疾病，鼠疫杆菌已成为生物战和生物恐怖主义的潜在病原体。虽然通过使用现代公共卫生措施，鼠疫的环境暴发在很大程度上得到了控制，但这种病原体作为战争和恐怖手段的潜在用途，需要更详细地了解鼠疫杆菌的发病机制，以促进确定疫苗开发和治疗的目标。目前还没有针对腺鼠疫或肺鼠疫的疫苗。对最近发表的鼠疫杆菌基因组的检测表明，鼠疫杆菌可能表达6种不同的autotransporter （AT）蛋白（称为Yap，耶尔森氏菌autotransporter protein）。AT蛋白已经在各种各样的病原体中被鉴定出来，正如它们的名字所暗示的那样，蛋白质的初级序列足以指导通过细菌外膜的运输。此外，在已知AT功能的情况下，这些蛋白质一致与毒力相关。从了解鼠疫菌与其宿主的相互作用以及潜在的候选疫苗的角度来看，在鼠疫菌基因组中存在6个这样的序列是令人感兴趣的。因此，为了开始研究鼠疫杆菌的这些ATs，我们提出以下具体目标：目的1。鼠疫杆菌中Yaps的表达及定位分析。从基因组序列中预测了6种不同的Yaps，它们可能不会同时表达或以相同的方式定位。更好地了解每种基因表达和定位的条件，将为其潜在功能提供有价值的线索。目标2。Yaps在鼠疫菌毒力中的作用分析。将在鼠疫杆菌CO92菌株中构建每个yap基因的突变体，然后使用小鼠感染模型测试其毒力。目标3。Yaps的功能分析。我们将开始研究Yaps的功能，通过检测表达单个Yaps的大肠杆菌的各种已知功能，这些功能以前与自转运蛋白相关。

DESCRIPTION (provided by applicant): Yersinia pestis is a human pathogen that is the causative agent of plague. Unfortunately, due to the high mortality rates and severe disease caused by Y. pestis, Y. pestis has emerged as a potential agent of biological warfare and bioterrorism. Although environmental outbreaks of plague largely have been controlled through the use of modern public health measures, the potential use of this pathogen as an agent of warfare and terror necessitates a more detailed understanding of the pathogenesis of Y. pestis to facilitate the identification of targets for vaccine development and treatment. No vaccine is currently available for either the bubonic or pneumonic form of plague. Examination of the recently published genome of Y. pestis indicates that Y. pestis potentially could express six different autotransporter (AT) proteins (designated Yap for Yersinia autotransporter protein). AT proteins have been identified in a wide variety of pathogens and as their name suggests the primary sequence of the protein is sufficient to direct transport across the outer membrane of the bacterium. In addition, in cases where the function of the AT is known these proteins are uniformly associated with virulence. The presence of six such sequences in the Y. pestis genome is of interest from the standpoint of understanding the interaction of Y. pestis with its host as well as potential vaccine candidates. Thus, to begin to study these ATs of Y. pestis we propose the following specific aims: Aim 1. Analysis of expression and localization of the Yaps in Y. pestis. Six different Yaps are predicted from the genome sequence and they may not all be expressed at the same time or localized in the same manner. A better understanding of the conditions under which each of the yaps is expressed and localized will provide valuable clues as to its potential function. Aim 2. Analysis of the role of Yaps in the virulence of Y. pestis. Mutants of each of the yap genes will be constructed in the CO92 strain of Y. pestis and then tested for virulence using the mouse model of infection. Aim 3. Functional analysis of the Yaps. We will begin to investigate the function of the Yaps by testing E. coli expressing individual Yaps for a variety of known functions previously associated with autotransporter proteins.