Reconstitution of isolated Rieske Fe-S protein into a Rieske-depleted cytochrome b6-f complex.

The Rieske Fe-S protein can be isolated from the cytochrome b6-f complex by means of chromatography on a hydroxyapatite column in the presence of detergent. Depletion of the cytochrome complex from the Rieske protein results in the loss of oxidoreductase activity, as well as the ability to reduce cytochrome b6. The Rieske Fe-S protein can be reconstituted into the Rieske-depleted complex by removal of the Triton X-100 molecules associated with the protein fractions, and their substitution by lipids. Upon reconstitution the complex is reactivated, and the role of the Rieske Fe-S protein in the reduction of both plastocyanin and cytochrome b6 can be demonstrated.