MO: Functional Genomic Investigations of Dissolved Organic Carbon Cyling at the Sapelo Island Microbial Observatory

University Of Georgia Research Foundation Inc, Athens GA

Investigators

Abstract

Degradation by marine bacteria of the organic carbon dissolved in coastal seawater is a major process in the ocean carbon cycle. However, the details of this important process seem hopelessly complex. The thousands of distinct compounds that make up this dissolved organic carbon (DOC) pool and the thousands of bacterial species that participate in its metabolism are largely unknown to science, and this greatly impedes efforts to understand the fate of carbon in coastal oceans. In turn, this hinders development of predictive models of carbon cycling in a changing ocean. Overcoming this impediment requires an environmental functional genomics approach. This project will use gene expression patterns in bacterial communities at the Sapelo Island, GA LTER site to identify the components of terrestrial- and marine-derived organic matter that are assimilated and metabolized in the coastal ocean. By sequencing expressed genes directly from seawater at times when ecosystem inputs are the most distinct, the patterns of DOC supply and flux will be discerned. Expression studies of model bacterial strains cultured from coastal communities will be used to identify the biochemical pathways for metabolism of individual carbon compounds and determine the compounds that are preferentially transported and metabolized from the marine DOC pool. The Sapelo Island Microbial Observatory project will improve understanding of the role of land-margin ecosystems in the global carbon cycle, addressing how cellular-level activities mediated by bacteria affect major biogeochemical processes. It will provide opportunities for interdisciplinary training in microbial biogeochemistry and ecological genomics to students and postdoctoral associates, and will sponsor a research experience in microbial biology for promising high school biology students, broadening the participation of underrepresented groups in science. This project will develop novel informatics approaches for microbial ecologists that couple molecular sequence data with environmental context information, and will openly share databases and bioinformatics tools with the scientific community.