Dr. McLendon is supported by the Inorganic, Bioinorganic and Organometallic Chemistry Program to perform experimental studies of electron transfer in metalloproteins. McLendon has proposed to use three-helix peptide bundles to probe structural relationships in long-range electron coupling in proteins. Having demonstrated a synthetic methodology that allows systematic protein structural variations, rigidly linked acceptor/donor moieties may be introduced at known distances. This advancement in the art will allow the examination of distance dependence upon electron transfer along a helix. A second aspect of the proposal involves derivatization of hydrogen bonding sites on the helix. In the absence of significant perturbations to helix structure or stability, the proposed modification will help determine the role of hydrogen bonding pathways in electronic coupling. Additionally, electron transfer through side chains and the effect of aromatic residues on the rate of electron transfer will be investigated. Understanding electron transfer in metalloproteins has been limited by the ability of chemists to control protein structure, particularly access to redox mediating functional groups. By coupling established measurement techniques with systematic protein structural variation methods, roadblocks to the full elucidation of this phenomenon may be overcome.
