Research with Colleen Byron

Leakage of reactive oxygen species (ROS) in the mitochondrial electron transport system can lead to oxidative damage of the membrane bound enzymes and complexes that are part of this system. Previous studies by Musatov and co-workers at The University of Texas Health Sciences Center in San Antonio have shown that highly toxic lipid by-products such as 4-hydroxy-2-nonenal can react with and modify the amino acid side chains of lysine, histidine, and cysteine in cytochrome c oxidase and other electron transport proteins. Identification of which amino acids in the sequence have been modified can be helpful in understanding the mechanism and extent of oxidative damage. My collaborator, Frank E. Frerman of the Department of Pediatrics at the University of Colorado Health Sciences Center, and I have been working with a mitochondrial membrane enzyme, electron transfer flavoprotein:ubiquinone oxidoreductase (ETF:QO) which accepts electrons from fatty acid and amino acid oxidation processes and transfers them to the ubiquinone pool of electron transport. While our studies have so far been kinetic, electrochemical, and spectroscopic in nature, we wish to extend the characterization of this enzyme by investigating its response to oxidative stress. Students involved with this project would react wild type and clinically relevant mutated forms of ETF:QO with 4-hydroxy-2-nonenal and use mass spectrometry to identify the sequence location of the amino acids modified.

Dr. Byron and two Ripon College students present results of their research at the most recent National American Chemical Society Meeting in Chicago (March, 2007).