During cellular respiration reaction, mitochondrial Cytochrome c Oxidase (CcO) utilizes a unique heme-copper binuclear active site to carry out the enzymatic four-electron four-proton reduction of dioxygen (O2) to water; this reaction is coupled with the process of proton pumping and the biological ATP production. While O2-reactivity at heme-copper centers is well studied, alternative redox reactions catalyzed by these systems have not been much explored. Our research goal is to contribute to a fundamental understanding of the non-native redox reactions (i.e., both reduction and oxidation) that can be catalyzed by heme-copper model systems. We previously described how synthetic heme-copper centers reduce nitrite ion to NO(g) or the reverse, oxidize NO(g) to nitrite. This redox interconversion of nitrite and NO(g) is believed to occur as part of CcO’s function, which is intimately tied to cellular O2 balance. This seminar will focus on our recent studies on other redox reactions catalyzed by the related synthetic heme-copper systems.
Professor Shabnam Hematian
Department of Chemistry and Biochemistry
University of North Carolina - Greensboro
Chemistry Building, Room 400