Expasy logo

ENZYME

ENZYME entry: EC 1.6.5.5

PURL: https://purl.expasy.org/enzyme/EC/1.6.5.5
Accepted Name
NADPH:quinone reductase
Alternative Name(s)
quinone oxidoreductase
zeta-crystallin
Reaction catalysed
2 a quinone + NADPH + H(+) = 2 a 1,4-benzosemiquinone + NADP(+)
Comment(s)
  • Specific for NADPH.
  • Catalyzes the one-electron reduction of certain quinones, with the orthoquinones 1,2-naphthoquinone and 9,10-phenanthrenequinone being the best substrates.
  • Dicoumarol (cf. EC 1.6.5.2) and nitrofurantoin are competitive inhibitors with respect to the quinone substrate.
  • The semiquinone free-radical product may be non-enzymically reduced to the hydroquinone or oxidized back to quinone in the presence of O2.
  • Abundant in the lens of the eye of some mammalian species.
Cross-references
BRENDA1.6.5.5
EC2PDB1.6.5.5
ExplorEnz1.6.5.5
KEGG Ligand Database for Enzyme Nomenclature1.6.5.5
IUBMB Enzyme Nomenclature1.6.5.5
MEDLINEFind literature relating to 1.6.5.5
MetaCyc1.6.5.5
Rhea expert-curated reactions1.6.5.5
UniProtKB/Swiss-Prot
P28304, QOR1_ECOLIQ53FA7, QORX_HUMANO97764, QOR_BOVIN
P11415, QOR_CAVPOQ08257, QOR_HUMANQ28452, QOR_LAMGU
P42865, QOR_LEIAMP47199, QOR_MOUSEQ0MVN8, QOR_PIG
Q5R4S7, QOR_PONABP43903, QOR_PSEAEQ6AYT0, QOR_RAT
P40783, QOR_SALTYO74489, QOR_SCHPOP38230, QOR_YEAST
Q9AYU1, QR1_TRIVSQ9HCJ6, VAT1L_HUMANQ80TB8, VAT1L_MOUSE
Q8JFV8, VAT1_DANREQ99536, VAT1_HUMANQ62465, VAT1_MOUSE
Q3MIE4, VAT1_RATP19333, VAT1_TETCF

View entry in original ENZYME format
View entry in raw text format (no links)
All UniProtKB/Swiss-Prot entries referenced in this entry, with possibility to download in different formats, align etc.
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 1.6.5.-
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 1.6.-.-
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 1.-.-.-