THE ROLE OF NOVEL SURFACE PROTEINS IN YERSINIA PESTIS VIRULENCE

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目及 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 鼠疫耶尔森氏菌是鼠疫的病原体，在感染过程中可以结合到哺乳动物宿主细胞的表面，以及侵入哺乳动物宿主细胞。 这一活动是一个活跃的研究领域，充分了解导致巨噬细胞和淋巴细胞持续存在的感染序列对于剖析这种重要的革兰氏阴性菌的致病性至关重要。 为此，我们产生了一个全面的TnphoA文库来鉴定Y的所有表面蛋白。鼠疫 通过DNA序列分析鉴定了大量的侵袭素样蛋白。 在候选基因中，鼠疫菌的invasin蛋白（由YPO 3944基因编码）是鼠疫菌的一个新的致病基因。鼠疫菌CO 92）是一个大的3013个残基的蛋白质，由LysM基序组成，在革兰氏阴性细菌入侵蛋白的子集中保守，以及细菌Ig样结构域的串联重复序列。虽然这个假定的Y。鼠疫侵袭素蛋白在所有测序的Y.尽管鼠疫菌生物型中存在这种蛋白质，但尚未研究该蛋白质在鼠疫耶尔森氏菌发病机制中的确切作用。本项目的具体目标是： 1. 利用phoA报告系统和真实的时间PCR确定该基因在各种环境条件下的调控。 2. 通过定点诱变产生缺失突变，并在细胞培养侵袭试验和摩西发病模型中比较该突变体与野生型亲本菌株的毒力。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Yersina pestis, the etiologic agent of plague, can bind to the surface, as well as invade, mammalian host cells during the infection process. This activity is an active area or research and a full understanding of the infection sequence leading to persistence in macrophages and lymphatic cells is essential in dissecting the pathogenicity of this important Gram negative bacterium. To this end, we generated a comprehensive TnphoA library to identify all surface proteins of Y. pestis. Analysis of this reporter fusion library identified a number of invasin like proteins by DNA sequence analysis. On candidate gene, the Yersinia pestis putative invasin protein (encoded by gene YPO3944 in Y. pestis CO92) is a large 3013 residue protein composed of a LysM motif, conserved in a subset of Gram negative bacterial invasion proteins, as well as tandem repeats of a bacterial Ig-like domain. Although this putative Y. pestis invasin protein is conserved in the genome of all sequenced Y. pestis biotypes, the exact role of this protein in the pathogenesis of Y.pestis has not been examined. Our specific goals for this project are to: 1. Determine the regulation of this gene under various environmental condtions using the phoA reporter system and real time PCR. 2. Generate a deletion mutation by site-directed mutagenesis and compare the virulence of this mutant with the wild-type parental strain in cell culture invasion assays and the mosue pathogenesis model.