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。该项目涉及Osedax属内一群胆小的蠕虫与它们的微生物共生体之间的共生。这些关键物种在世界各地的深海鲸鱼瀑布中发现，深度从25米到3000米不等。有证据表明，对于双方来说，最有可能的营养来源是鲸骨中存在的胶原蛋白，然而，人们对每个伴侣在这方面的具体功能知之甚少。虽然所有Osedax物种都有相似之处，但它们在共生种群的身份和生物量上存在差异。这些差异可能导致观察到的Osedax物种之间的生态差异。从共生菌中获取基因组信息将有助于我们理解这些独特的共生体所使用的代谢机制。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往往是有问题的。为了解决这个问题，研究人员将使用一种最近开发的技术来纯化特定的细菌细胞，称为免疫磁分离(Magneto-Fish)。随后对三个Osedax物种中的共生体进行的基因组比较将提供机会，不仅可以了解关于细菌共生体的特定新陈代谢和生化的重要细节，而且还可以确定导致细菌与高等生物之间亲密相互作用的因素。共生研究本质上是多学科的，这个瑞项目将直接向本科生介绍微生物学、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.