NADPH—hemoprotein reductase

NADPH—hemoprotein reductase
Identifiers
EC number	1.6.2.4
CAS number	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 / EGO
Search PMC articles PubMed articles

In enzymology, a NADPH—hemoprotein reductase (EC 1.6.2.4) is an enzyme that catalyzes the chemical reaction

NADPH + H⁺ + n oxidized hemoprotein $\rightleftharpoons$ NADP⁺ + n reduced hemoprotein

The 3 substrates of this enzyme are NADPH, H⁺, and oxidized hemoprotein, whereas its two products are NADP⁺ and reduced hemoprotein.

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 in common use include CPR, FAD-cytochrome c reductase, NADP---cytochrome c reductase, NADP---cytochrome reductase, NADPH-dependent cytochrome c reductase, NADPH:P-450 reductase, NADPH:ferrihemoprotein oxidoreductase, NADPH---cytochrome P-450 oxidoreductase, NADPH---cytochrome c oxidoreductase, NADPH---cytochrome c reductase, NADPH---cytochrome p-450 reductase, NADPH---ferricytochrome c oxidoreductase, NADPH---ferrihemoprotein 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, and phosphate). It has 2 cofactors: FAD, and FMN.

Structural studies

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.

References

• Haas E, Horecker BL and Hogness TR (1940). "The enzymatic reduction of cytochrome c, cytochrome c reductase". J. Biol. Chem. 136: 747–774. 
• Horecker BL (1950). "Triphosphopyridine nucleotide-cytochrome c reductase in liver". J. Biol. Chem. 183: 593–605. 
• 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. PMID 4389465. 
• GIBSON QH, PALMER G, WHARTON DC (1965). "STUDIES ON THE MECHANISM OF MICROSOMAL TRIPHOSPHOPYRIDINE NUCLEOTIDE-CYTOCHROME C REDUCTASE". J. Biol. Chem. 240: 921–31. PMID 14275154. 
• WILLIAMS CH Jr, KAMIN H (1962). "Microsomal triphosphopyridine nucleotide-cytochrome c reductase of liver". J. Biol. Chem. 237: 587–95. 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. 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. doi:10.1073/pnas.94.16.8411. PMC 22938. PMID 9237990. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=22938. 
• 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.