Micrococcus denitrificans cytochrome

Lam, Y., and Nicholas, D. J. D. (1969). A nitrite reductase with cytochrome oxidase activity from Micrococcus denitrificans. Biochim. Biophys. Acta 180, 459-472. 

R. palustris has an even more extended 80 s loop. Micrococcus denitrificans C550 and R. capsulata a are remarkably similar molecules, differing by no more than the cytochromes c of spinach and Euglena. In spite of the difference in metabolic roles, respiration vs. photosynthesis, csso seems like a perfectly normal member of the cj class. 

Little is known of the catalytic properties of cytochrome b investigators must rely on the spectrum characterization of cytochrome b rather than on its enzymic activity to evaluate the purity of the preparation. Little is known of the heme group of mammalian cytochrome b. It is significant that cytochrome b extracted from Micrococcus denitrificans and Pseudomonas denitrificans contains protoheme, the same heme as is in cytochrome c. The nature of the binding between the prosthetic group and the protein is not known. The firm thioester bond in cytochrome c probably is not present in cytochrome b. 

Smith, L., Newton, N. and Scholes, P. (1966) Reaction of cytochrome c oxidases of beef heart and Micrococcus denitrificans with mammalian and bacterial cytochromes c. In Hemes and Hemoproteins (B. Chance, R. W. Estabrook and T. Yonetani, eds.), pp. 395-403, Academic Press, New York. 

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