Roles for glutathione transferases in antioxidant recycling

Plant Signal Behav. 2011 Aug;6(8):1223-7. doi: 10.4161/psb.6.8.16253. Epub 2011 Aug 1.


Uniquely among the plant glutathione transferases, two classes possess a catalytic cysteine capable of performing glutathione-dependent reductions. These are the dehydroascorbate reductases (DHARs) and the lambda-class glutathione transferases (GSTLs). Using immobilized GSTLs probed with crude plant extracts we have identified flavonols as high affinity ligands and subsequently demonstrated a novel glutathione-dependent role for these enzymes in recycling oxidized quercetin. By comparing the activities of DHARs and GSTLs we now propose a unified catalytic mechanism that suggests oxidized anthocyanidins and tocopherols may be alternative polyphenolic substrates of GSTLs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anthocyanins / metabolism
  • Antioxidants / metabolism*
  • Cysteine / metabolism
  • Glutathione Transferase / genetics
  • Glutathione Transferase / metabolism*
  • Molecular Structure
  • Oxidation-Reduction
  • Oxidoreductases / genetics
  • Oxidoreductases / metabolism*
  • Plant Proteins / genetics
  • Plant Proteins / metabolism
  • Quercetin / metabolism*
  • Tocopherols / metabolism


  • Anthocyanins
  • Antioxidants
  • Plant Proteins
  • Quercetin
  • Oxidoreductases
  • glutathione dehydrogenase (ascorbate)
  • Glutathione Transferase
  • Cysteine
  • Tocopherols