Carbon degrading enzymes: Basic kinetics and responses to temperature
Microorganisms are incredibly diverse and play important roles in the global cycling of carbon and nutrients. In particular, microbes determine how much carbon is sequestered in soils and sediments versus mineralized back to carbon dioxide. Since carbon and nutrients are usually present in complex chemical structures, we know that certain microbes must produce extracellular enzymes to cycle these elements. However, we still know very little about the particular microbes that regulate carbon balance, or the factors that control their activity.
The goal of this project is to examine the frequencies of enzyme-producing microbes versus competitor microbes in soils and marine environments. The prediction is that enzyme producers should be relatively more common in low diffusion environments, such as soils and sediments. In high diffusion environments, such as ocean water, enzyme producers should lose out in competition with microbes that acquire carbon and nutrients directly. The research will involve collecting and culturing microbes from different environments and analyzing their identity and function. Students will learn how to set up microbial cultures, extract and sequence DNA, and conduct assays of extracellular enzyme activity. Project time allocation: 70% laboratory, 20% computer analysis, 10% fieldwork