Amino acid sequence of dog heart cytochrome c.

The amino acid sequences of cytochromes c from many species have been shown to be homologous, the number of residues which differ depending on the biological relationship of the species being compared (2, 3). At the time the present study of dog heart cytochrome c was undertaken, only t’hc sequences of horse (4) and human (5) cytochromes c were known. It was essential, therefore, to determine the over-all sequence in some det.ail. At present, this is the only known sequence of a cytochrome c which has been reported for a member of the carnivores.