Oxidases and Oxygenases
Oxidases catalyze the transfer of two electrons from a donor to oxygen, producing hydrogen peroxide. They usually contain flavin co-enzyme or metal in the active site to form LTQ and TPQ as a co-factor (such as the copper amine oxidases). Oxygenases catalyze the incorporation of oxygen into a substrate. Oxygenases include dioxygenases that incorporate both oxygen atoms into a substrate and monooxygenases (including heme oxygenases and cytochrome P450 enzymes) that incorporate one oxygen atom as a hydroxyl group into the substrate while the other oxygen atom is reduced to water.