Respiratory activity and ATP of microorganisms in the North Equatorial Current of the Atlantic Ocean

✍ Scribed by B. Werf; J. H. Vosjan

• Publisher: Springer Netherlands
• Year: 1984
• Tongue: English
• Weight: 119 KB
• Volume: 50
• Category: Article
• ISSN: 0003-6072
• DOI: 10.1007/bf00404949

✦ Synopsis

The terminal component of the electron transport chain, cytochrome c oxidase (ferrocytochrome c -oxygenoxido reductase), was purified from Bacillus subtilis W23. The enzyme was solubilized with alkylglucosides and purified to homogeneity by cytochrome c affinity chromatography. The enzyme showed absorption maxima at 414 and 598 nm in the oxidized form and at 443 and 601 nm in the reduced form. Upon reaction with carbon monoxide of the reduced purified enzyme the absorption maxima shifted to 431 and 598 nm. Sodium dodecylsulphate-polyacrylamide gel electrophoresis indicated that the purified enzyme is composed out of three subunits with apparent molecular weights of 57000, 37 000 and 21000. This is the first report on a bacterial aa3-type oxidase containing three subunits. The functional properties of the enzyme were comparable with those of other bacterial cytochrome c oxidases. The reaction catalysed by this oxidase was strongly inhibited by cyanide, azide and monovalent salts. Furthermore a strong dependency on negatively charged phospholipids of cytochrome c oxidase activity was observed. Crossed immunoelectrophoresis experiments strongly indicated a transmembranal localization of cytochrome c oxidase.