Cloning and heterologous expression of NAD(P)H:quinone reductase of Arabidopsis thaliana, a functional homologue of animal DT-diaphorase

FEBS Lett. 1999 Dec 17;463(3):382-6. doi: 10.1016/s0014-5793(99)01625-7.


In higher plants, NAD(P)H:quinone reductase (NQR) is the only flavoreductase known to reduce quinone substrates directly to hydroquinones by a two-electron reaction mechanism. This enzymatic activity is believed to protect aerobic organisms from the oxidative action of semiquinones. For this reason plant NQR has recently been suggested to be related to animal DT-diaphorase. A cDNA clone for NQR of Arabidopsis thaliana was identified, expressed in Escherichia coli, purified and characterized. Its amino acid sequence was found related to a number of putative proteins, mostly from prokaryotes, with still undetermined function. Conversely, in spite of the functional homology, sequence similarity between plant NQR and animal DT-diaphorase was limited and essentially confined to the flavin binding site.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Arabidopsis / enzymology
  • Arabidopsis / genetics*
  • Base Sequence
  • Binding Sites
  • Cloning, Molecular
  • DNA, Complementary / chemistry
  • Escherichia coli / genetics
  • Escherichia coli / metabolism
  • Gene Expression
  • Molecular Sequence Data
  • NAD(P)H Dehydrogenase (Quinone) / biosynthesis
  • NAD(P)H Dehydrogenase (Quinone) / chemistry
  • NAD(P)H Dehydrogenase (Quinone) / genetics*
  • Recombinant Proteins / chemistry
  • Sequence Alignment


  • DNA, Complementary
  • Recombinant Proteins
  • NAD(P)H Dehydrogenase (Quinone)