This award in the Bioinorganic, Inorganic and Organometallic Chemistry Program supports research in the laboratories of Dr. Joan S. Valentine at the University of California Los Angeles. The research to be performed involves the study of both beneficial and toxic metal-catalyzed reactions of dioxygen, superoxide or peroxide with organic substrates. The ferric peroxo complex of protoporphyrin IX dimethyl ester will be used as a model compound to elucidate the nature of intermediates involved in the reactions of heme iron-containing enzymes. Additionally, the reactions of iron-neuromelanin analogs and copper metallothioneins with ascorbate and carbohydrates will be examined to investigate the role of such compounds in oxidative damage. Finally, modified stellacyanin will be used to model the toxic reactivity of adventitiously formed oxidation catalysts. Biologically important reactions of dioxygen and its metabolites are often catalyzed by metalloenzymes. The proposed studies will advance our understanding of the mechanisms of metal-catalyzed oxygenation reactions suspected to be involved in degenerative diseases.
