Mutations of Chlamydomonas reinhardtii affecting the cytochrome bf complex

The properties of some photosynthetic mutants of Chlamydomonas reinhardtii which were known to have impaired intersystem electron transport were examined. A new mutant, F18, is described which lacked all the redox centres of the cytochrome bf complex. The known mutant ac21 was shown to contain a cytochrome bfcomplex that lacked the Rieske iron-sulphur centre. Cytochrome b-559_LP was present in all strains examined at about the same concentration as cytochrome fin the wild ype and so is unlikely to be an integral component of the cytochrome bfcomplex.Cytochrome bf complexCytochrome b-559Iron-sulfur centerPhotosynthetic mutant(Chlamydomonas reinhardtii)