Investigating Membrane Proteins with Magnetic Resonance Spectroscopy

Miami University, Oxford OH

Investigators

Abstract

This research award in the Chemistry of Life Processes (CLP) program supports work by Professor Gary A. Lorigan in the Department of Chemistry and Biochemistry at Miami University in Oxford, Ohio to probe the structure of membrane peptides using Electron Paramagnetic Resonance (EPR) spectroscopy. Membrane peptides are difficult to study because they are very hydrophobic. Thus, the peptides are incorporated into a lipid bilayer membrane. The objective of the proposed research is to develop state-of-the-art EPR spectroscopic techniques to probe the structural properties of integral membrane peptides. These techniques will be widely applicable to all peptide and protein systems. The pulsed EPR technique of ESEEM spectroscopy will be used to measure short-range distances (less than 8 Angstroms) between a spin label and deuterium nuclei on integral membrane peptides. It is expected that the ESEEM technique will become a valuable biophysical tool for measuring distances on chemical and biological systems. EPR spectroscopy is approximately a thousand fold more sensitive than NMR spectroscopy. This new biophysical technique can move the field forward by providing an efficient and easy way to distinguish between alpha-helical, 3-10-helical and beta-sheet structural segments. The potential future benefits of this basic research are to develop new techniques to obtain structural information on membrane proteins. This methodology is useful for all peptides and proteins, associated with energy shortages, electron transport, photosynthesis, and greenhouse gases. Through this research program undergraduate, graduate and postdoctoral students from diverse backgrounds are trained in advanced techniques in biophysical chemistry, helping to strengthen the US STEM workforce.