Role of Chemotaxis, Motility and Adhesins during Initiation of the Earthworm-Verminephrobacter Symbiosis

大多数植物和动物，包括人类，都有有益的细菌伴侣，这是增进健康所必需的，但大多数关于细菌与宿主相互作用的信息都是基于病原体研究。蚯蚓是土壤系统的重要成员，为有益细菌在动物宿主中的定植提供了实验模型。一种常见的堆肥蠕虫，爱森尼虫（Eisenia fetida），在类似肾脏的器官中维持细菌，并将这些共生细菌沉积到卵囊中，在蚯蚓胚胎中定植。本研究探讨了细菌共生体在早期发育过程中检测、迁移并定植宿主特定器官的机制。病原体和有益细菌成功的关键因素是靶向并附着于适当的组织，然后进行随后的生长。在这项研究中获得的关于细菌定植的信息将更好地装备科学家和医学专业人员来对抗疾病和促进有益微生物。这项研究有几个目标：(1)确定相关基因，(2)确定共生细菌用于定位组织的感觉机制，(3)确定细菌结合的宿主细胞表面特征。方法包括遗传学分析基因功能，生物化学和细胞染色方法鉴定细胞表面蛋白质和糖。这项工作将揭示有益细菌成功定植正确组织的关键机制。这项工作产生的基因组数据将通过适当的公共基因数据库提供。研究结果将及时公布，并在实验室网站上更新。活动包括对青年科学家（包括女性）的教育，以3-8年级儿童动手演示的形式向公众宣传，以及为经验丰富的科学家和公众提供网页更新。这项研究将影响包括发育生物学、病理生物学和土壤生态学在内的一系列科学学科。

Most plants and animals, including humans, have beneficial bacterial partners that are necessary to enhance health, yet most information about bacterial interactions with hosts is based on pathogen studies. Earthworms, keystone members of the soil system, offer an experimental model for colonization of animal hosts by beneficial bacteria. A common composting worm, Eisenia fetida, maintains bacteria within kidney-like organs and deposits these symbiotic bacteria into egg capsules to colonize earthworm embryos. This study investigates mechanisms that enable bacterial symbionts to detect, migrate into and colonize a particular organ of their host during early development. Crucial elements for the success of both pathogens and beneficial bacteria are the targeting of and attachment to appropriate tissue, followed by subsequent growth. Information about bacterial colonization gained in this study will better equip scientists and medical professionals to combat disease and promote beneficial microbes. The study has several goals: to (1) determine genes involved, (2) identify sensory mechanisms used by symbiotic bacteria to locate tissue, and (3) identify cell surface features of the host to which bacteria bind. Approaches include genetics to analyze gene function, and biochemistry and cell staining methods to identify cell surface proteins and sugars. This work will reveal key mechanisms beneficial bacterial use to successfully colonize the correct tissue. Genomic data generated by this work will be available through appropriate public gene databases. Findings will be published in a timely manner and updated on the lab website. Activities include education of young scientists, including women, and public outreach in the form of hands-on demonstrations for children in grades 3-8, and webpage updates for both experienced scientists and the public. This research will impact a range of scientific disciplines including developmental biology, pathobiology, and soil ecology.