MO: Photoheterotrophic Microbes of the Mid-Atlantic Bight

海洋中的碳循环和其他生物地球化学过程被认为几乎完全由两种类型的海洋微生物控制：1)光养微生物--像植物一样，利用二氧化碳和其他植物营养物质合成有机物质，同时产生氧气；2)异养微生物--像动物一样，在利用氧气的同时，将有机物质氧化回二氧化碳和其他植物营养物质。最近使用分子方法进行的研究发现了一些新的微生物--光异养细菌--它们将光养和异养结合在一起。光异质营养将从根本上改变我们对水生生态系统中碳循环和其他生物地球化学过程的理解。该项目将在大西洋中部海湾建立一个微生物观测站(MO)，以解决有关光异养微生物的多样性、丰度和活性的问题。该项目将对光异养微生物的相关基因进行测序，以表征它们的多样性和新陈代谢。丰度将通过流式细胞术(蓝藻)、红外线细菌叶绿素显微镜(AAP细菌)和与针对蛋白紫质基因的多核苷酸探针的荧光原位杂交来估计。各种有机化合物和二氧化碳的消耗将使用显微放射自显影和荧光显微镜在单细胞水平上进行分析。更广泛的影响这一拟议的气象组织项目将提供几个独特的机会，促进对学生和普通公众进行水生微生物生态学和环境微生物学方面的教育。该项目将通过特拉华大学和基因组研究所(TIGR)之间日益密切的联系让研究生参与。美国历史上最悠久的黑人大学林肯大学的本科生将于今年夏天在特拉华州进行独立研究。基什曼博士的实验室在每周参观特拉华大学刘易斯分校的设施(每年约有1000名参观者)期间，以及在每年吸引约1万名参观者的刘易斯的年度开放日期间，都会展出。

The carbon cycle and other biogeochemical processes in the oceans were thought to be controlled nearly entirely by two types of marine microbes: 1) phototrophs - microbes which, like plants, synthesize organic material using CO2 and other plant nutrients while producing oxygen; and 2) heterotrophs - microbes which, like animals, oxidize organic material back to CO2 and other plant nutrients while using oxygen. Recent studies using molecular approaches have discovered some novel microbes--photoheterotrophs--that combine phototrophy with heterotrophy. Photoheterotrophy would fundamentally alter our understanding of the carbon cycle and other biogeochemical processes in aquatic ecosystems. This project would establish a Microbial Observatory (MO) in the Mid-Atlantic Bight to address questions about the diversity, abundance, and activity of photoheterotrophic microbes. The project will sequence relevant genes of photoheterotrophic microbes to characterize their diversity and metabolism. Abundance will be estimated by flow cytometry (cyanobacteria), infra-red microscopy of bacteriochlorophyll (AAP bacteria), and fluorescence in situ hybridization with polyribonucleotide probes targeting proteorhodopsin genes. Consumption of various organic compounds and CO2 will be assayed at the single cell level using microautoradiography together with fluorescence microscopy. Broader Impacts This proposed MO project would offer several unique opportunities to contribute to the education of students and the general public in aquatic microbial ecology and environmental microbiology. The project will involve graduate students via a growing connection between the University of Delaware and The Institute for Genomic Research (TIGR). Undergraduates from Lincoln University, the nation's oldest historical black college, will conduct independent research in the summer in Delaware. Dr. Kirchman's lab is featured during weekly tours of University of Delaware facilities in Lewes (about 1000 visitors per year) and during Coast Day, an annual open-house in Lewes that attracts about 10,000 visitors.