NADPH—hemoprotein reductase
NADPH-Cytochrome P450 reductase dimer, Rattus norvegicus
Identifiers
EC no.	1.6.2.4
CAS no.	9023-03-4
Databases
IntEnz	IntEnz view
BRENDA	BRENDA entry
ExPASy	NiceZyme view
KEGG	KEGG entry
MetaCyc	metabolic pathway
PRIAM	profile
PDB structures	RCSB PDB PDBe PDBsum
Gene Ontology	AmiGO / QuickGO
Search PMC articles PubMed articles NCBI proteins

In enzymology, a NADPH—hemoprotein reductase is an enzyme that catalyzes the chemical reaction

NADPH + H⁺ + n oxidized hemoprotein NADP⁺ + n reduced hemoprotein

The three substrates of this enzyme are NADPH, H⁺, and oxidized hemoprotein, whereas its two products are NADP⁺ and reduced hemoprotein. It has two cofactors: flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN).

This enzyme belongs to the family of oxidoreductases, specifically those acting on NADH or NADPH with a heme protein as acceptor. The systematic name of this enzyme class is NADPH:hemoprotein oxidoreductase. Other names include cytochrome P450 reductase, ferrihemoprotein P-450 reductase, and NADPH-dependent cytochrome c reductase.

As of late 2007, 10 structures have been solved for this class of enzymes, with PDB accession codes 1AMO, 1B1C, 1J9Z, 1JA0, 1JA1, 1YQO, 1YQP, 2BF4, 2BN4, and 2BPO.

• Haas E, Horecker BL, Hogness TR (1940). "The enzymatic reduction of cytochrome c, cytochrome c reductase". J. Biol. Chem. 136: 747–774. doi:10.1016/S0021-9258(18)73034-2.
• Horecker BL (1950). "Triphosphopyridine nucleotide-cytochrome c reductase in liver". J. Biol. Chem. 183 (2): 593–605. doi:10.1016/S0021-9258(19)51185-1.
• Lu AY, Junk KW, Coon MJ (1969). "Resolution of the cytochrome P-450-containing omega-hydroxylation system of liver microsomes into three components". J. Biol. Chem. 244 (13): 3714–21. doi:10.1016/S0021-9258(18)83427-5. PMID 4389465.
• GIBSON QH, PALMER G, WHARTON DC (1965). "Studies on the Mechanism of Microsomal Triphosphopyridine Nucleotide-Cytochrome C Reductase". J. Biol. Chem. 240 (2): 921–31. doi:10.1016/S0021-9258(17)45262-8. PMID 14275154.
• WILLIAMS CH Jr; KAMIN H (1962). "Microsomal triphosphopyridine nucleotide-cytochrome c reductase of liver". J. Biol. Chem. 237 (2): 587–95. doi:10.1016/S0021-9258(18)93967-0. PMID 14007123.
• Masters BS, Bilimoria MH, Kamin H, Gibson QH (1965). "The mechanism of 1- and 2-electron transfers catalyzed by reduced triphosphopyridine nucleotide-cytochrome c reductase". J. Biol. Chem. 240 (10): 4081–8. doi:10.1016/S0021-9258(18)97152-8. PMID 4378860.
• Sevrioukova IF, Peterson JA (1995). "NADPH-P-450 reductase: structural and functional comparisons of the eukaryotic and prokaryotic isoforms". Biochimie. 77 (7–8): 562–72. doi:10.1016/0300-9084(96)88172-7. PMID 8589067.
• Wang M, Roberts DL, Paschke R, Shea TM, Masters BS, Kim JJ (1997). "Three-dimensional structure of NADPH-cytochrome P450 reductase: prototype for FMN- and FAD-containing enzymes". Proc. Natl. Acad. Sci. U.S.A. 94 (16): 8411–6. Bibcode:1997PNAS...94.8411W. doi:10.1073/pnas.94.16.8411. PMC 22938. PMID 9237990.
• Munro AW, Noble MA, Robledo L, Daff SN, Chapman SK (2001). "Determination of the redox properties of human NADPH-cytochrome P450 reductase". Biochemistry. 40 (7): 1956–63. doi:10.1021/bi001718u. PMID 11329262.
• Munro AW, Noble MA, Robledo L, Daff SN, Chapman SK (2001). "Determination of the redox properties of human NADPH-cytochrome P450 reductase". Biochemistry. 40 (7): 1956–63. doi:10.1021/bi001718u. PMID 11329262.
• Scrutton NS; Grunau, A; Paine, M; Munro, AW; Wolf, CR; Roberts, GC; Scrutton, NS (2003). "Electron transfer in human cytochrome P450 reductase". Biochem. Soc. Trans. 31 (Pt 3): 497–501. doi:10.1042/BST0310497. PMID 12773143.
• Scrutton NS; Grunau, A; Paine, M; Munro, AW; Wolf, CR; Roberts, GC; Scrutton, NS (2003). "Electron transfer in human cytochrome P450 reductase". Biochem. Soc. Trans. 31 (Pt 3): 497–501. doi:10.1042/BST0310497. PMID 12773143.