The
NADPH oxidase (nicotinamide adenine dinucleotide phosphate-oxidase) is a membrane-bound
enzyme complex that faces the extracellular space. It can be found in the plasma membrane as well as in the membranes of
phagosomes used by
neutrophil white blood cells to engulf microorganisms.
Isoforms are designated NOX1, NOX2, NOX3, and NOX4.