Vibrio Virulence Determinants in a Benign Colonization

这项研究的长期目标是确定遗传和细胞事件， 有益细菌在动物上皮组织中的定植。这种特殊的共生感染 发光的发光器官的鱿鱼Euprymna candiopes由发光细菌弧菌fischeri将是 作为一个模型系统，通过它来解决这些目标。最近的调查集中在 事件的特征的启动和持久性的协会使用新孵化的，未殖民 幼鱼和共生的成年乌贼。实验使用细菌突变体和宿主细胞事件， 操纵和分析复杂的信号和反应序列， 认识彼此最近开发的基因组工具，包括细菌和宿主微阵列， 在V. fischeri基因组序列和13，000个成员的鱿鱼EST基因文库上，提供了一个特殊的 有机会了解遗传机制的启动和持续这一点 有益的联系。 拟议的研究计划包括三个具体目标： 1.研究细菌首次接触宿主时相互信号活动的作用 2.了解共生体与宿主吞噬细胞和上皮细胞之间的相互作用 3.为了确定驱动共生体每天排出和再生的机制 该系统作为有益和致病性弧菌感染的模型， 弧菌毒力的进化。具体来说，基因组比较已经揭示了 对共生体和病原体都重要的定殖/毒力因子。这里提出的工作将 也提供了关于与水生无脊椎动物的特定的、稳定的联系如何服务的新信息 as environmental环境reservoirs水库for human人类pathogenic致病Vibrio弧菌species种类.

The long-term objectives of this research areto define the genetic and cellular events that characterize colonization of animal epithelial tissue by beneficial bacteria. The specific symbiotic infection of the light-emitting organ of the squid Euprymna scolopes by the luminousbacterium Vibrio fischeri will be used as a model system through which to address these objectives. Recent investigations have centered on the events characterizing the initiation and persistence of the association using newly hatched, uncolonized juveniles, and symbiotic adult squid. Experiments use bacterial mutants and host cellular events to manipulate and assay the complex succession of signalingand responses by which the host and bacterium recognize each other. Recently developed genomic tools, including bacterial and host microarrays based on the V. fischeri genome sequence and a 13,000 member squid EST gene library, provide an exceptional opportunity to understand the genetic mechanisms underlying the initiation and persistence of this beneficial association. The proposed research plan integrates 3 specific aims: 1. To examine the role of reciprocal signaling activities as the bacterium first encounters the host 2. To understand the interactions between the symbiontsand host phagocytes and epithelialcells 3. To determine the mechanisms driving the daily expulsion and regrowth of the symbionts This system serves as a model of both beneficial and pathogenic Vibrio infection, as well as the evolution of virulence in vibrios. Specifically,genomic comparisons have already revealed shared colonization/virulence factors important to both symbionts and pathogens. The work proposed here will also provide new informationabout how specific, stable associationswith aquatic invertebrates may serve as environmentalreservoirs for human pathogenic Vibrio species.