Conformational Changes upon Reduction of Cytochrome c

Abstract

The X-ray structure analysis of reduced cytochrome c from tuna hearts is now at 2.45 ÅA resolution, and we can see significant changes in polypeptide chain conformation between this and the oxidized state. In the report of the 2.8 Å analysis of ferricytochrome c (Dickerson et al., 1971a), attention was focused on evolutionary homologies and on the information that evolutionary conservatism through many species could give about the essential parts of the cytochrome molecule. With the addition of the present ferrocytochrome c structure, we can begin to have a clearer idea of how the electron transfer process takes place.