Marine viruses are the most numerous, most diverse and the least genetically characterized biological entities on Earth. Through cycles of infection, replication and host cell lysis, viruses impact multiple pathways and processes involved in the biodiversity and evolution of host organisms, primarily bacteria, and the functioning of marine environments as a whole. Metagenomic approaches, or those that facilitate the analysis of genomic material from whole environmental communities, will be used to investigate the diversity of viral and bacterial host populations from two surface marine water samples (collected from the Dry Tortugas, Florida and the Gulf of Maine) and one poorly oxygenated estuarine sample from the Chesapeake Bay. Additionally, sequencing of viral and bacterial community DNA will be used to determine if viruses are responsible for the apparent genomic differences observed between the fully sequenced cultured strains of Prochlorococcus and SAR11 and their respective environmental relatives. Prochlorococcus, a photosynthetic microbe, and SAR11, a group of dissolved organic carbon-utilizing microbes with light-harvesting capabilities, are incredibly abundant in marine surface waters and play important roles in the cycling of essential nutrients. High-throughput sequencing of these organisms and the viruses that infect them will shed light on the origins of genetic variation in naturally occurring marine microorganisms.
The sequence data resulting from this project will be made available to the scientific community through deposition into public databases and will expand the current size of viral metagenomic data 100-fold. Middle-school students and teachers from Washington D.C. public schools will participate directly in the project and be introduced to genomic approaches through the DISCOVER GENOMICS! outreach program at the J. Craig Venter Institute. Futhermore, teacher fellows will extend their training during a funded summer internship designed to bring the world of marine microbial ecology to the classroom.