Molecular structure of a heme-copper redox center of the escherichia coli ubiquinol oxidase: Evidence and model

Abstract

Biochemical, spectroscopic, and molecular biological studies on bacterial respiratory oxidases in the last decade have greatly increased our understanding of a molecular structure of the metal centers which catalyze the dioxygen reduction chemistry. Based upon the latest physicochemical and molecular biological evidence and theoretical consideration of a folding mechanics of membrane proteins, we propose here the tertiary structure of the heme-copper metal center of the Escherichia coli bo-type ubiquinol oxidase, the cyto-chrome bo complex. The molecular mechanism of electron transfer-coupled proton pumping in the heme-copper respiratory oxidases is reviewed on the basis of this predicted model. © 1994 BY The Journal of Biochemistry.