Structure of Yeast Cytochrome c

I. Monomer and Dimer Interconversion

Abstract

Among Saccharomyces oviformis M₂ cytochrome c, sulfhydryl type (cyc. c-SH), thiosulfate type (cyt. c-S-SO₃^-), and disulfide type (cyt.c-S-S-cyt. c) could be converted into each other, and the reaction of the sulfhydryl group in cytochrome c can be explained as follows:
cyt. c-S^-+Cu⁺⁺→cyt.c-S-S-cyt.c
cyt. c-S-S-cyt.c+RS^--2cyt.c-S^-+RSSR
cyt.c-S-S-cyt.c+SO₃^--→cyt.c-S^-+cyt.c-S-SO₃^-
cyt.c-S-SO₃^-+RS^-→cyt.c-S^-+RSSR+SO₃^--
And there were no fundamental differences in the enzymatic activity and the absorption specta among them.
The authors wish to thank Dr. K. Kakiuchi, Institute for Protein Research, Osaka University, for the molecular weight measurements, and Dr. G. Meshizuka and his collaborators, Tokyo Metropolitan Isotope Centre, for their technical advice and assistance.