RUI: MSB: Collaborative: Symbiont separation and investigation of the novel heterotrophic Osedax symbiosis using comparative genomics

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。细菌与动物伙伴关系的多样性和普遍性直到现在才得到充分认识。在许多海洋环境中，这些共生体在维持高生产力方面发挥着关键作用。这个项目关注的是一组无肠蠕虫和它们的微生物共生体之间的共生关系。这些关键物种在世界范围内深海鲸鱼群中被发现，深度从25米到3000米不等。有证据表明，双方最有可能的营养来源是存在于鲸骨中的胶原蛋白，然而，在这方面，我们对双方的具体功能能力知之甚少。虽然所有的Osedax物种都有相似之处，但它们在共生种群的特性和生物量上存在差异。这些差异可能会导致观察到的Osedax物种之间的生态差异。从共生细菌中获得基因组信息将有助于我们了解这些独特共生中使用的代谢机制。然而，由于难以将细菌从宿主组织和细胞中分离出来，对单个共生体基因组的分析常常存在问题。为了解决这个问题，研究人员将使用最近开发的一种技术来净化特定的细菌细胞，这种技术被称为免疫磁分离（Magneto-FISH）。随后对三种Osedax物种共生体的基因组比较将提供机会，不仅可以了解有关细菌共生体的特定代谢和生物化学的重要细节，还可以确定细菌与高等生物之间密切相互作用的结果和促进因素。共生研究本质上是多学科的，芮项目将直接向本科生引入微生物学、分子生态学、基因组学和共生等学科。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).The diversity and pervasiveness of bacterial partnerships with animals is only now being fully appreciated. In many marine environments these symbioses play critical roles in sustaining high productivity. This project concerns symbioses between a group of gutless worms within the genus Osedax and their microbial symbionts. These keystone species are found at deep-sea whale falls worldwide at depths ranging from 25 to 3000 meters. Evidence suggests that the most likely nutritional source for both partners is collagen present within the whale bone, however, very little is known about the specific functional capabilities of each partner in this regard. Although all Osedax species have similarities, they differ in the identity and biomass of their symbiotic populations. These differences can contribute to observed ecological differences among Osedax species. The acquisition of genomic information from the symbiotic bacteria will facilitate our understanding of the metabolic machinery used in these unique symbioses. Analysis of single symbiont genomes, however, is often problematic due to difficulties in separating the bacteria from the host tissue and cells. To address this problem, the investigators will use a recently developed technique for purifying specific bacterial cells called immuno-magnetic separation (Magneto-FISH). Subsequent genomic comparisons between symbionts in three Osedax species will offer the opportunity to not only learn important details regarding the specific metabolism and biochemistry of the bacterial symbionts, but to also identify the factors that result from, and contribute to, intimate interactions between bacteria and higher organisms. Symbiosis research is inherently multi-disciplinary and this RUI project will directly introduce undergraduates to the disciplines of microbiology, molecular ecology, genomics, and symbiosis.