NSF Award
0084211
Picoplankton, small planktonic microorganisms ranging in diameter from 0.2 to 2.0 mm, are the most abundant cellular organisms in the world's oceans. At concentrations of ranging from 10,000 to 1,000,000 cells /ml worldwide, these microorganisms consume an estimated 20-50 % of marine primary productivity. Planktonic microbes are also biochemically versatile, mediating most of the key chemical transformations of carbon, nitrogen, and sulfur that occur in the oceanic biosphere. However, very little is known about the biology, physiology and genetics of these globally important microbes - mainly because some of the most dominant types have resisted cultivation. This project will characterize cosmopolitan and abundant, but uncultured, picoplankton species using newly developed genomic technologies. Specifically, the project will sequence, annotate and analyze large insert chromosomal DNA libraries prepared from naturally occurring planktonic microorganisms. These data will provide hitherto unavailable information on uncultured microorganisms that have a high abundance and ubiquitous global distribution. Genomic organization, gene content, and functional protein distributions of planktonic microbes will become available for the first time. Furthermore, the new approaches and tools developed will significantly advance and extend current Microbial Observatory efforts in the ocean and other diverse environments. Our approach will significantly increase the general understanding of uncultivated microorganisms that largely mediate the flux of energy and matter in the world's oceans. Data resulting from this effort will also provide the foundation necessary for constructing DNA microarrays, designed for high throughput monitoring of the variability and gene expression of diverse, globally significant marine microbial species. Ultimately, the approaches developed in this research will provide detailed insight into the variability, activity, and significance of important microbial communities from any site.
