Most effective bactericidal system within phagocytes-

H2O2-MPO-halide system is the most efficient bactericidal system of neutrophils H2O2 is not able to efficiently kill microbes by itself. the azurophilic granules of neutrophils contain the enzyme myeloperoxidase (MPO), in the presence of a halide such as Cl-, conves H2O2 to hypochlorite(OCl2-) which is a potent antimicrobial agent that destroys microbes by halogenation (in which the halide is bound covalently to cellular constituents) or by oxidation of proteins and lipids (lipid peroxidation). NADPH oxidase pathway Robbins pathology 9th ed page 79