In this project funded by the Chemical Catalysis Program of the Chemistry Division, Carmen Works of Sonoma State University will study the mechanism of catalyzed reversible oxidation of molecular hydrogen in model compounds of iron-only hydrogenases. The approach is to first synthesize dimeric iron complex models of the enzyme active site, and then to use these molecules to test the hypothesis that light labilizes CO in these complexes to produce a model for the uninhibited form of the enzyme active site and that the coordination site of CO is occupied by a solvent molecule. The series of experiments to be performed include: CO dependent kinetics of the reactions of the photoproduct, kinetic solvent effects, temperature studies to determine activation parameters, spectroscopic analysis to monitor reactions of the photoproduct with molecular hydrogen, and quantum yield determinations. The broader impacts involve training undergraduate students in research methods, incorporating relevant materials into lecture and laboratory courses, and broadly disseminating the research results via publications and presentations at conferences.
This work will deepen our understanding of biological enzymes that utilize and generate hydrogen. Potential longer term impacts of the work could involve developing efficient methods to generate hydrogen as a clean fuel source and to use hydrogen in fuel cells.
