Purification, and some molecular and enzymatic features of a novel ccb-type cytochrome c oxidase from a microaerobic denitrifier, Magnetospirillum magnetotacticum.
A novel ccb-type cytochrome c oxidase was purified from the magnetic bacterium, Magnetospirillum magnetotacticum MS-1. The enzyme was composed of three subunits with M(r)'s of 43,000, 34,000 and 28,000, respectively, and contained 0.91 mol of protoheme, 2.0 mol of heme c and 0.70 g atom of copper per mol of minimal structural unit. One mol of enzyme oxidized 187 mol of horse heart ferrocytochrome c and 34.4 mol of M. magnetotacticum ferrocytochrome c550/s. The cytochrome c oxidase activity of the enzyme was 50% inhibited by 12 microM KCN. The enzyme seems to function as the terminal oxidase in microaerobic respiration.
Department of Life Science, Faculty of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama, Japan.
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Tamegai
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Fukumori
D001419:Bacteria / Q000201:enzymology*; D002458:Cell Fractionation; D003574:Cytochrome c Group / Q000378:metabolism; D003576:Electron Transport Complex IV / Q000145:classification / Q000302:isolation & purification / Q000378:metabolism*; D006418:Heme / Q000032:analysis; D007501:Iron / Q000032:analysis; D008280:Magnetics; D010084:Oxidation-Reduction; D011487:Protein Conformation; D013053:Spectrophotometry
D003574:Cytochrome c Group; D006418:Heme; D007501:Iron; D003576:Electron Transport Complex IV