Collaborative Research: Epsilonproteobacteria From Terrestrial Springs and Caves

Epsilonproteobacteria是变形菌门中最缺乏特征的分支，尽管病原体Helicobacter和Campylobacter一直受到关注。这群细菌对环境的重要性，包括它们在碳、氮和硫循环中的作用，才刚刚开始得到重视。Epsilonproteobacteria存在于各种富含硫的环境中，比如洞穴和深海热液喷口。拟议的研究将(1)根据从环境样本和纯培养物中检索的DNA序列诊断分类关系，(2)区分可能导致广泛的epsilonproteobacterium多样性的机制。除了发现生活在天然硫化物泉和洞穴中代表性不足的微生物外，本研究还将解决有关陆地地下水系统物种多样性，多样性控制（基于生态型）以及微生物与其栖息地之间潜在的生物地球化学相互作用的重要问题。泉水与地下水有着密切的联系，容易受到负面的人为活动（例如，被忽视、过度使用、开发）的影响，而有限的数据使人们无法完全了解许多地下水生态系统是多么稀有或受到威胁。研究结果将为水资源管理者更好地理解生态系统多样性提供依据。这个跨学科项目与路易斯安那州立大学地球微生物学研究项目的建立相吻合。将强调研究生和本科生的培训，并通过两所大学的方案倡议鼓励少数民族的参与。

The Epsilonproteobacteria are the most poorly characterized division within the Proteobacteria, despite ongoing attention given to the pathogens, Helicobacter and Campylobacter. The environmental importance of this group of bacteria, including their roles in the carbon, nitrogen and sulfur cycling is just beginning to be appreciated. Epsilonproteobacteria are found in a variety of sulfur-rich environments, such as caves and deep-sea hydrothermal vents. The proposed research will (1) diagnose taxonomic relationships based on DNA sequences retrieved from both environmental samples and from pure cultures, and (2) differentiate among the mechanisms that may have led to extensive epsilonproteobacterial diversity. Beyond discovery of underrepresented microbes living in natural sulfidic springs and caves, this research will address important questions regarding species diversity in terrestrial groundwater systems, controls of diversity (based on ecotype), and potential biogeochemical interactions between microbes and their habitats. Springs are intimate links to groundwater that are susceptible to negative anthropogenic activities (e.g., neglect, overuse, exploitation), and limited data have precluded a complete appreciation for how rare, or threatened, many groundwater ecosystems are. The results of this study will provide water resource managers with a better understanding of ecosystem diversity. This interdisciplinary project coincides with the establishment of the Geomicrobiology research program at LSU. Graduate and undergraduate training will be emphasized and minority participation will be encouraged through programmatic initiatives at both universities.