Affinity chromatography purification of cytochrome c oxidase and b-c1 complex from beef heart mitochondria. Use of thiol-sepharose-bound Saccharomyces cerevisiae cytochrome c.

A method for simultaneous purification of cytochrome c reductase and cytochrome c oxidase using a cytochrome c affinity column is presented. Cytochrome c from Saccharomyces cerevisiae was linked to an activated thiol-Sepharose gel via its Cys-102 residue located far from the lysine residues on the front side of the molecule, responsible for the interaction with the reductase and oxidase. In previously reported affinity chromatography techniques these lysine residues most probably reacted with the column. Cytochrome c oxidase and reductase from bovine heart mitochondria bind specifically to the affinity column and can be recovered separately at different ionic strength in the elution buffer. The enzymes are highly pure and active.