DISSERTATION RESEARCH: Ecosystem Consequences of Life History Strategies: Bacteriophage and Bacteria in a Denitrifying Environment

Stanford University, Stanford CA

Investigators

Abstract

The striking abundance of bacteriophage (viruses that infect bacteria) in the environment has prompted many questions about their ecological and evolutionary roles in nature. Bacteriophage often kill their bacterial hosts and such viral-caused mortality has been shown to have important consequences for nutrient cycling and the maintenance of biological diversity. This project will characterize the interactions between bacteria that consume nitrate (denitrifying bacteria) and the bacteriophage that infect these bacteria. Denitrification is an important process in many natural environments, as well as in engineered environments such as wastewater treatment plants. However, the role of phage in these communities remains poorly understood. We will determine 1) whether the interactions between phage and bacteria in this system can be predicted from earlier studies of much simpler microbial model communities, and 2) how interactions between phage and bacteria affect the efficiency and stability of the denitrification process. Improved understanding of this denitrifying community will lead to improved functional performance in engineered environments, as well as a better understanding of the factors influencing the function of natural ecosystems.