Reconstitution of Cytochrome c Oxidase from a Copper-depleted Enzyme and Cu

Copper can be removed from bovine cytochrome c oxidase with bathocuproine disulfonate under anaerobic conditions in the presence of reduced cytochrome c. The copper-depleted enzyme is relatively inactive. Upon replacement of copper with Cui-acetonitrile, more than the original activity is regained. The rate of O2 consumption catalyzed by the reconstituted enzyme is unaffected by catalase; the product of reduction is presumably water. It is probable, therefore, that the enzymic activity of cytochrome c oxidase from bovine heart muscle is copper-dependent.