Cytochrome oxidase and its derivatives. VIII. Formation and properties of the ‘oxygenated’ from of cytochrome oxidase and its reconversion to ferrous and ferric oxidase

摘要: Abstract 1. The ‘oxygenated’ compound of cytochrome c oxidase used in our experiments is more stable than the previous reports. It quantitatively reversible to ferrous oxidase. 2. best formed with an excess O 2 after reduction a minimum amount dithionite. can also be at low tension, but then contains some ferric 3. Its formation from ferrocyanide-reduced remains incomplete and subsequent by dithionite incomplete. 4. Cyanide does not inhibit its If only ferricytochrome no 3 reduced presence cyanide dithionite, there reaction . 5. anaerobic monophasic fast. In contrast, that biphasic, initial fast followed much slower rate , depends on concentration. 6. dissolved comes temporary standstill when one-third absorbance increase 444 mμ has been reached. 7. Ethyl hydrogen peroxide reacting forms similar compound. 8. Hydrogen donors known react peroxidase-H complexes, particularly pyrogallol, accelerate transformation oxidase, though comparable 9. These results strengthen evidence for cytochromes indicate this difference disappeared