Abstract
Photosynthetic electron flow in the bacterium R. sphaeroides involves 2 c-type cytochromes, 1 membrane-bound and the other a soluble protein, cytochrome c2. Membranes deficient in cytochrome c2 were used for photo-oxidation studies, with and without the addition of purified cytochrome c2. The results favor a series interrelation, membrane cytochrome c-cytochrome c2-reaction center.