Mutants of Yeast Deficient in Cytochrome C.

YTOCHROME C is an ideal protein for biochemical studies because of its ease of isolation and low molecular weight. Its primary structure from a number of species is entirely (cf. SMITH, MATSUBARA, MCDOWALL and ROTHFUS 1963) or partially (cf. TUPPY 1958) known. Therefore, any system exhibiting genetic control of cytochrome c would be of considerable interest for investigating geneprotein relationships. In a previous investigation, a mutant of yeast was shown to have a decreased concentration of cytochrome c controlled by a single gene. The cytochrome c isolated from this mutant was found to differ from wild-type cytochrome c by a number of criteria indicating differences in primary structure ( SLONIMSKI and SHERMAN, in preparation). The investigation reported herein deals primarily with the isolation and genetic analyses of other cytochrome c deficient mutants.