Reaction: NADPH + H+ + n oxidized hemoprotein = NADP+ + n reduced hemoprotein
Other name(s): CPR; FAD-cytochrome c reductase; NADPcytochrome c reductase; NADPcytochrome reductase; NADPH-dependent cytochrome c reductase; NADPH:P-450 reductase; NADPH:ferrihemoprotein oxidoreductase; NADPHcytochrome P-450 oxidoreductase; NADPHcytochrome c oxidoreductase; NADPHcytochrome c reductase; NADPHcytochrome p-450 reductase; NADPHferricytochrome c oxidoreductase; NADPHferrihemoprotein reductase; TPNH2 cytochrome c reductase; TPNH-cytochrome c reductase; aldehyde reductase (NADPH-dependent); cytochrome P-450 reductase; cytochrome c reductase (reduced nicotinamide adenine dinucleotide phosphate, NADPH, NADPH-dependent); dihydroxynicotinamide adenine dinucleotide phosphate-cytochrome c reductase; ferrihemoprotein P-450 reductase; reduced nicotinamide adenine dinucleotide phosphate-cytochrome c reductase; reductase, cytochrome c (reduced nicotinamide adenine dinucleotide phosphate)
Systematic name: NADPH:hemoprotein oxidoreductase
Comments: A flavoprotein containing both FMN and FAD. This enzyme catalyses the transfer of electrons from NADPH, an obligatory two-electron donor, to microsomal P-450 monooxygenases (e.g. EC 220.127.116.11, unspecific monooxygenase) by stabilizing the one-electron reduced form of the flavin cofactors FAD and FMN. It also reduces cytochrome b5 and cytochrome c. The number n in the equation is 1 if the hemoprotein undergoes a 2-electron reduction, and is 2 if it undergoes a 1-electron reduction.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9023-03-4
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