All of the following enzymes may contribute in generating free oxygen radicals within neutrophils for killing intracellular bacteria, except-

NADPH oxidase called the phagocyte oxidase, which oxidizes NADPH (reduced nicotinamide adenine dinucleotide phosphate) and, in the process, conves oxygen to superoxide ion (O2 * ) Superoxide is then conveed by superoxide dismutase into hydrogen peroxide (O2 * + 2H+ - H2O2) glutathione peroxidase major function is to protect cells from oxidative damage by regeneration of glutathione. Fenton reaction: H2O2 + Fe2+ -Fe2++ OH- + OH. ref robbins basic pathology 9th ed page 38