Genetic Analysis of Beneficial Bacterial Colonization

专利授权R01GM119627项目总结 我的实验室的目标是描述细菌和它们的细胞之间的分子通讯 动物宿主导致特异性和可再现的定殖。为了实现这一目标，实验室研究了 诉鱼-鱿鱼系统该系统是有利的，因为细菌通过天然途径定植， 感染，所有动物在细菌接种到海水中的三个小时内都会定植， 可以进行详细的遗传操作，感染的精确部位可以直接在 活的动物宿主，允许尖端的遗传和基因组方法。专注于鱿鱼是如何 由特定的共生体可重复地定殖，以排除数百万的竞争细菌， 海水，揭示了细菌聚集和生物膜形成在促进特定宿主- 微生物相互作用最近，我们的全球遗传筛选，以确定殖民因素揭示了多种新的 生物膜激活剂，并确定了孤儿组氨酸激酶，其作为Syp生物膜的负调节剂 体内发育阐明动物体内定植和生物膜发育的调控途径 我们将（1）剖析新的组氨酸激酶途径的分子细节，（2）在高时间定义 和空间分辨率的必要步骤，建立这种互惠关系，和（3） 使用遗传和代谢组学方法表征新的定殖因子的作用。以来 我们的研究结果表明，费氏弧菌与宿主相互作用的策略在其他宿主-微生物系统中是保守的， 将适用于了解其他有益关联以及病原体之间的相互作用 细菌及其宿主

PROJECT SUMMARY FOR PARENT GRANT R01GM119627 The objective of my laboratory is to characterize how molecular communication between bacteria and their animal hosts leads to specific and reproducible colonization. To accomplish this goal, the laboratory studies the V. fischeri-squid system. This system is advantageous because bacteria colonize through the natural route of infection, all animals are colonized within three hours of bacterial inoculation into the seawater, the bacteria can be subject to detailed genetic manipulation, and the precise site of infection can be imaged directly in the live animal host, allowing for cutting edge genetic and genomic approaches. Focusing on how squid are reproducibly colonized by the specific symbiont, to the exclusion of the millions of competing bacteria in seawater, has revealed key roles for bacterial aggregation and biofilm formation in promoting specific host- microbe interactions. Recently our global genetic screen to identify colonization factors revealed multiple novel biofilm activators and identified an orphan histidine kinase, which acts as a negative regulator of Syp biofilm development in vivo. To elucidate the pathways governing colonization and biofilm development in the animal host we will (1) dissect the molecular details of the novel histidine kinase pathway, (2) define at high temporal and spatial resolution the steps necessary for the establishment of this mutualistic relationship, and (3) characterize the role of new colonization factors using genetic and metabolomic approaches. Since the strategies used by V. fischeri to interact with its host are conserved in other host-microbe systems, our findings will be applicable to understand other beneficial associations as well as interactions between pathogenic bacteria and their hosts.