Matthew Sullivan, Ph.D.
University of Arizona, Department of Ecology and Evolutionary Biology
Ocean Viruses: Mucking with Microbial Metabolism in the Global Oceans
Wednesday - March 18, 2009
Pacific Forum – 3:00 p.m.
Primary production of vast oceanic regions is numerically dominated by the unicellular cyanobacteria Prochlorococcus and Synechococcus making them significant drivers of global carbon and oxygen biogeochemistry in the oceans. Their viruses (cyanophages) play a critical role in both shaping and benefiting from host genome content. Remarkably, this is true even for central metabolic processes such as photosynthesis, where it appears that cyanophages have altered the evolutionary trajectory of these global photosystems. We now expand this work to explore a dominant viral type in the oceans (T4-like myoviruses) and to expand our understanding of how viruses are “mucking with host metabolism”. Using comparative genomics of 15 T4-like cyanophages, and analysis of published viral metagenomes we evaluate (1) how phage-driven genetic diversification of ‘host genes’ might influence other important global biogeochemical cycles, and (2) the variability observed across available cyanophage isolate genome sequences as well as wild cyanophage genome fragments.