NADPH—hemoprotein reductase

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

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

NADPH + H⁺ + n oxidized hemoprotein $\rightleftharpoons$ 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.

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, 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.