This NSF-sponsored microbial observatory, a collaboration with oceanographer Craig Carlson, is focused on understanding the role of microorganisms in the oceanic carbon cycle.

Dr. Alexander Treusch, a post-doc working on this project, uses ARB to determine phylogenetic relationships of cloned sequences.

Our study site in the Western Sargasso Sea, a.k.a. BATS, is an example of an oligotrophic ocean gyre. Seventy percent of the oceans are gyres, regions of clear water and low productivity. The amount of dissolved organic carbon in these regions of the ocean is about the same as the total amount of CO₂ in the atmosphere; hence, understanding how microorganisms use this carbon is important for deciphering the global carbon cycle.

We employ bioinformatics techniques to design DNA probes for ribosomal RNAs and use them to monitor long-term changes in the ocean surface microbial community. For these measurements we use technologies such as quantitative DNA/RNA hybridization, PCR, fluorescence in situ hybridization, chromosomal painting and image analysis.

To gain insight into the complex interactions taking place within whole microbial plankton communities we study their responses to experimental manipulation. Such experiments are made possible by the close proximity of the Bermuda Biological Station to our study site.

For more information about this project and other Microbial Observatories, go to the Science Education Resource Center. This project is also supported by the Gordon and Betty Moore Foundation.