EVOLUTION OF VIRULENCE BY GENE ACQUISITION

描述（改编自申请人的摘要）：基因获取是 对致病菌的进化和出现至关重要。获得的特征 使它们能够在水库中生存，并殖民， 伤害它们感染的宿主。产滋贺毒素E.大肠杆菌（STEC），如 例如E. coli0157：H7和选择的非0157：H7产毒E.大肠杆菌，提供 独特的机会来研究进化方面的收购 毒力性状 E.含有编码滋贺毒素的基因的大肠杆菌在遗传上是多样的， 但毒力菌株几乎总是在两个明确的系统发育中发现， 集群（STEC 1和STEC 2组）。研究人员建议研究 系统地，使用比较基因组分析， 获得，以确定推定的毒力位点的分布，并 辨别这些特征的获得顺序。他们还将评估 这些病原体在牛科动物和人类中基因表达的克隆性质。 该项目产生的数据将阐明毒力 生物体积累必要的遗传成分是成功的 病原体

DESCRIPTION (Adapted from the Applicant's Abstract): Gene acquisition is crucial for the evolution and emergence of pathogenic bacteria. Traits acquired by pathogens enable them to survive in their reservoirs, and colonize and injure the hosts that they infect. Shiga toxin-producing E. coli (STEC), such as E. coli 0157:H7 and selected non-0157:H7 toxin-producing E. coli, provide a unique opportunity to study the evolutionary aspect of the acquisition of virulence traits. E. coli containing genes encoding Shiga toxins are phylogenetically diverse, but virulent strains are almost always found in two well defined phylogenetic clusters (STEC 1 and STEC 2 groups). The investigators propose to study systematically, using comparative genome analysis, the traits these pathogens have acquired, to determine the distribution of putative virulence loci, and to discern the sequence of acquisition of these traits. They will also assess the clonal nature of gene expression of these pathogens in bovids and humans. Data generated by this project will elucidate the mechanisms used by virulent organisms to accumulate the necessary genetic components to be successful pathogens.