title: Purification and properties of the soluble cytochromes c-550 and c-556 from the bacterium Aquaspirillum itersonii.
abstract: Two c-type cytochromes were isolated from cells of the gram-negative bacterium Aquaspirillum itersonii grown under low aeration in the presence of nitrate. The major component, cytochrome c-550, was equated with the (single) c-type cytochrome previously reported to be present in this organism [Clark-Walker, G. D. & Lascelles, J. (1970) Arch. Biochem. Biophys. 136, 153-159], although a significantly higher molecular mass was apparent in the present work. The complete amino acid sequence of this cytochrome is reported in the accompanying paper. A second soluble c-type cytochrome, designated c-556, was also isolated. The molecular mass, isoelectric point, spectrum, midpoint oxidation reduction potential and amino acid composition of this monoheam cytochrome are reported. The possible relationship of this cytochrome to other cytochromes c-556 is discussed.
mesh_terms: D000596:Amino Acids / Q000032:analysis; D003574:Cytochrome c Group / Q000302:isolation & purification*; D004591:Electrophoresis, Polyacrylamide Gel; D007525:Isoelectric Focusing; D008970:Molecular Weight; D010084:Oxidation-Reduction; D012995:Solubility; D013053:Spectrophotometry; D013139:Spirillum / Q000201:enzymology*
chemical_list: D000596:Amino Acids; D003574:Cytochrome c Group; C020267:cytochrome c556; C031732:cytochrome C-550