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.
Tamegai
H
H
Department of Life Science, Faculty of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama, Japan.
Fukumori
Y
Y
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