Function
Under normal circumstances, the complex is latent in neutrophils and is activated to assemble in the membranes during respiratory burst.
NADPH oxidase generates superoxide by transferring electrons from NADPH inside the cell across the membrane and coupling these to molecular oxygen to produce superoxide anion, a reactive free-radical. Superoxide can be produced in phagosomes, which contain ingested bacteria and fungi, or it can be produced outside of the cell. In a phagosome, superoxide can spontaneously form hydrogen peroxide that will undergo further reactions to generate reactive oxygen species (ROS).
Superoxide kills bacteria and fungi by mechanisms that are not yet fully understood (see article on superoxide), but may inactivate critical metabolic enzymes, initiate lipid peroxidation, and liberate redox-active iron, which allows the generation of indiscriminate oxidants such as the hydroxyl radical. It is presumed that superoxide kills bacteria directly, as the virulence of many pathogens is dramatically attenuated when their superoxide dismutase (SOD) genes are deleted. However, downstream products of superoxide also include hydrogen peroxide and hypochlorous acid, the reactive agent in bleach.
Read more about this topic: NADPH Oxidase
Famous quotes containing the word function:
“The more books we read, the clearer it becomes that the true function of a writer is to produce a masterpiece and that no other task is of any consequence.”
—Cyril Connolly (1903–1974)
“It is not the function of our Government to keep the citizen from falling into error; it is the function of the citizen to keep the Government from falling into error.”
—Robert H. [Houghwout] Jackson (1892–1954)
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—Benjamin Lee Whorf (1897–1934)