Oxygen reduction reaction intermediates binding

Anaerobic reduction of ascorbate oxidase, AOox, by ascorbate ion is an eight-electron process. Initial reduction of the type 1 centre is reversed as the type 3 centre is reduced and it is suggested that type 1 copper is close to the substrate binding site and that type 3 is involved in the interaction with molecular oxygen. Azide, which can bind to type 2 copper, has no effect on the reduction process. A potentially catalytically active intermediate is formed in the reaction between ascorbate oxidase and hydrogen peroxide at pH 7.6, 0.01 M phosphate, and 25 °C ... 

---