An efficient affinity chromatography procedure for the isolation of mitochondrial cytochrome c oxidase and reductase is described. Saccharomyces cerevisiae cytochrome c was used as a ligand, bound to a thiol-Sepharose 4B gel through cysteine-107. In this way, the site of interaction of cytochrome c with cytochrome oxidase and reductase remained unmodified and available for binding to a number of partner enzymes. The procedure is adequate for the purification of all those proteins having in common the property of binding with high affinity to cytochrome c--e.g., cytochrome c oxidase, reductase, and peroxidase, sulfite oxidase, and reaction centers of photosynthetic bacteria.
Azzi, A., Bill, K., & Broger, C. (1982). Affinity chromatography purification of cytochrome c binding enzymes. Proceedings of the National Academy of Sciences of the United States of America, 79(8), 2447–2450. https://doi.org/10.1073/pnas.79.8.2447