Reaction of thionitrobenzoate‐modified yeast cytochrome <i>c</i> with monomeric and dimeric forms of beef heart cytochrome <i>c</i> oxidase

Abstract

Thionitrobenzoate-modified yeast cytochrome c was shown to react with both monomeric and dimeric forms of beef heart cytochrome c oxidase through subunit III. This cytochrome c derivative was found to inhibit electron transfer in the dimer but not in the monomer. These results are interpreted to show that the high affinity binding site for cytochrome c is a cleft at the interface between monomers in the cytochrome c oxidase dimer.