Microbial Observatories: Intra-annual Diversity and Dynamics of Chesapeake Bay Virioplankton

University Of Delaware, Newark DE

Investigators

Abstract

A grant has been awarded to Drs. K. Eric Wommack (University of Delaware), Feng Chen (University of Maryland), and D. Wayne Coats (Smithsonian Environmental Research Laboratory) to characterize novel viruses and investigate their role and importance in the annual plankton cycle of the Chesapeake Bay. For over a decade scientists have known that viruses are the most abundant biological entities in marine and aquatic environments. In the rich, productive estuarine waters of the Chesapeake, viral abundance is around 10 million viruses per milliliter; exceeding bacterial abundance by a factor of 10. Collectively these populations, comprised principally of bacterial and algal viruses, are known as the virioplankton. The specific identity of the vast majority of these strains is still unknown to science. This study will be the first to apply comprehensive characterization and monitoring of virioplankton populations within an estuary over several annual cycles. Methodological approaches will include the use of molecular genetic and genomics tools to identify changes in the composition and diversity of Chesapeake Bay virioplankton. These observations will be interpreted in light of the physio-chemical and biological changes which occur seasonally in the Chesapeake. In addition, viruses infecting important microorganisms occurring in the Chesapeake will be isolated in an effort to characterize specific virus-host interactions. The broad question poised to marine scientists since the discovery of high viral abundance is: what is the diversity of these viruses, and what role do they play in the maintenance and function of marine microbial ecosystems? Ultimately, these microbial communities comprised of bacteria, unicellular protists, and viruses determine the fate of nutrients and pollutants in coastal waters; and are at the center of the marine food web. A more complete understanding of the inner workings of marine microbial communities will assist in efforts to assess, maintain and even restore the health of marine and estuarine ecosystems.