Myeloperoxidase hydrogen peroxide substrate

Hydrogen peroxide is a substrate for myeloperoxidase, a multisubunit heme protein of M.W. 150,C, present in primary neutrophilic granules. The active prosthetic groups are two hemes covalently attached to the apoen-zyme. This enzyme catalyzes many kinds of oxidation reactions, but oxidation of halide ions to hypohalite ions appears to be the most important. Hypochlorite ion is the principal compound formed, although Br , I, and SCN (a pseudohalide) can also serve as substrates. The reaction catalyzed is... 

The catalase reaction can be seen to be a special case of Reaction 5.83 in which the substrate, AH2, is hydrogen peroxide.) Some examples of peroxidases that have been characterized are horseradish peroxidase, cytochrome c peroxidase, glutathione peroxidase, and myeloperoxidase. 

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