Type b Cytochromes in Respiratory Systems

The presence of different cytochrome 6 components in mitochondrial respiratory chain and their direct role in energy conservation has been postulated for many years. These postulations were based on anomalous kinetic and spectrophotomeric behavior of the 6 cytochromes in intact mitochondria and in phosphorylating submitochondrial particles (2-13). During 1970 and 1971 evidence was obtained by several workers pointing 

Hagihara, N. Sato, K. Takahashi, and S. Muraoka, in Organization of Energy Transducing Membranes (M. Nakao and L. Packer, eds.), p. 315. TJniv. of Tokyo Press, Tokyo, 1973 B. Hagihara, N. Sato, T. Fukuhara, K. Tsutsumi, and Y. Oyanagui, Cancer Res. 33, 2947 (1973). 

BUNJI HAGIHABA, NOBUHIBO SATO, AND TATEO YAMANAKA 

Different Type h Cytochromes in Mammalian Respiratory Systems 

The multiplicity of the cytochrome h components was first shown by Chance (2) in the mitochondrial fragments from beef heart. He suggested the presence of three type h cytochromes The first was characterized as succinate-reducible pigment with an a maximum at 562 nm the second as succinate-reducible in the presence of antimycin, having an a maximum at 566 nm and the third as reducible only by dithionite and having a broad a maximum from 556 to 566 nm. Subsequent studies have also shown the existence of at least two forms of cytochrome h in mitochondria 

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