Homology of Pseudomonas cytochrome c-551 with eukaryotic c-cytochromes.

The homology of Pseudomonas cytochrome c-551 with eukaryotic cytochromes c is examined with a computer-based procedure devised to determine whether similarities exist between these proteins. One method is given by which the more recently evolved cytochromes c might have arisen from the Pseudomonas protein. This procedure involves only common genetic phenomena and accounts for most of the structural differences between the bacterial and mammalian cytochromes. A time-scale relationship between the c-cytochromes from several microorganisms, a mold, yeast, and the eukaryotic organisms is proposed.