Kathryn M McCulloch
Associate Professor, Chemistry and Biochemistry, College of Science
Biography
Research Interests
Overview
Organisms have not evolved in a vacuum – instead, they have interacted with their environment, competed for resources with other species, and collaborated with other organisms to thrive. These various forces have led to the evolution of complex pathways that produce signaling molecules, secondary metabolites, or otherwise provide the organism with an evolutionary advantage. To date, these pathways offer both the opportunity to develop new therapies, such as antibiotics, and offer potential targets for defeating pathogens or promoting human health. The McCulloch group aims to understand the chemistry of enzymes found within specific pathways. Currently, we are studying oxidoreductases (enzymes that catalyze either oxidations or reductions) encoded within the bile acid induced operon of some gut bacteria. We use a recombinant approach to overexpress each protein, and then use a combination of X-ray crystallography and in vitro biochemical assays to develop a molecular understanding of their structures and chemical reactivities.
Bile Acid Metabolism
Our group is interested in understanding the transformation of primary bile acids - molecules synthesized in the liver and essential in the absorption of fat-soluble vitamins and nutrients, as well as important signaling molecules - into secondary bile acids by some species of gut bacteria. We use a recombinant approach to overexpress putative enzymes from this metabolic pathway and aim to determine the three-dimensional structures of these enzymes to answer important questions about how they work.