A grant has been awarded to Drs. Carlson (University of California Santa Barbara) and Giovannoni (Oregon State University) to investigate the cell biology and Biogeochemical activities of the major microbial groups in the open ocean. This project will focus geographically on the Bermuda Atlantic Time-series Study (BATS) site, which for the past decade has been a test bed for the development of advanced molecular techniques for measuring microbial diversity, and is one of the longest time-series studies of oceanographic conditions on the planet. The rich data set from BATS provides important physical, chemical and biological information that is used by the microbial observatory to understand how ocean conditions affect the activities of planktonic microorganisms. The ocean microbial observatory will apply a new high throughput cultivation technology developed at Oregon State University to identify, count and cultivate the major oceanic microbial groups that have not previously been cultured. Technologies will also be employed to characterize the quality and quantity of organic substrate utilization by these microorganisms.
Heterotrophic microorganisms use dissolved organic carbon (DOC) to grow. The global dissolved organic carbon (DOC) pool is estimated to be 685 Gt C, a value comparable to the mass of inorganic C in the atmosphere. Small perturbations in the metabolism of DOC by microorganisms could impact the balance between oceanic and atmospheric carbon dioxide, providing a strong impetus to understand how the dynamics and diversity of microorganisms affect DOM production, consumption and distribution in the oceans. The genomic DNA sequences, biochemical properties and patterns of DOC utilization of these organisms will be studied in the laboratory. This data will be used in field studies that document and explain natural patterns of change in microbial communities and DOC. In addition this project will also host summer courses at the Bermuda Biological Station for Research designed to expose graduate students to state-of-the-art molecular biology and oceanographic techniques.