Joshua Weitz, Ph.D.

SCOPE-ALOHA Project: Quantifying the Interplay Between Parasites and Predators in the North Pacific Ocean

Marine viruses affect microbial community structure and biogeochemical cycles in multiple ways, including negatively affecting, and potentially limiting, the density of target populations; modifying the metabolic activity of infected cells, including nutrient uptake rates; and stimulating production via the ‘viral shunt,’ in which cellular lysates are released back into the environment and then re-assimilated by non-targeted cells. Yet inferring the relative importance of virus-induced modifications of microbes and microbial cell fate is difficult in the face of competing ocean processes such as, for example, grazing by zooplankton.

In this collaborative effort, we will utilize data-driven modeling approaches to characterize the ecological roles of viruses in the North Pacific Subtropical Gyre. We will combine theoretical and computational analyses of complex marine food and parasite webs to assess how variation in the strength of cellular-scale mechanisms could modify community-scale properties. In parallel, we will utilize inverse modeling approaches to infer the strength of virus-induced effects on microbial communities. Results developed here will enable the incorporation of parameterized models of virus-host interactions into regional models of the ocean ecology of the North Pacific.

Bio:
Joshua Weitz is Professor of Biological Sciences at the Georgia Institute of Technology, where he also holds an adjunct appointment in physics as well as in electrical and computer engineering. He received his B.A. in physics from Princeton University in 1997 and his Ph.D. in physics from the Massachusetts Institute of Technology in 2003. Weitz is a Fellow of the American Association for the Advancement of Sciences, a Fellow of the American Academy of Microbiology, and awarded the Blaise Pascal International Chair of Excellence at the Institute of Biology at the Ecole Normale Superieure.

Weitz joined the Georgia Institute of Technology in 2007, where he directs a multidisciplinary research group focused on the ecology and evolution of viruses that infect microbes. His group develops theoretical and computational methods to characterize how viruses impact cells, populations, communities, and ecosystems.