NADPH oxidase activation

Glucose-6-phosphate dehydrogenase is required for the production of NADPH, an essential component of the NADPH oxidase system (1). The phagocyte NADPH oxidase system generates O^- ₂ by transferring e^- from NADPH to O₂ (2). Superoxide is metabolized to H₂O₂ by superoxide dismutase (3). Hydrogen peroxide can follow different metabolic pathways inside the cell. Myeloperoxidase can convert it into HOCl (4), which is involved in the oxygen-dependent killing of microorganisms in combination with other reactive oxygen species (5). Alternatively, hydrogen peroxide can be degraded to H₂O and O₂, thereby avoiding deleterious effect on the cell (6). Hydrogen peroxide can also diffuse outside the cell and can augment other defective cells (7).