Roles for glutathione transferases in antioxidant recycling.

TY - JOUR

T1 - Roles for glutathione transferases in antioxidant recycling.

AU - Edwards, Robert

AU - Dixon, D.P

AU - Steel, P.G

PY - 2011/8

Y1 - 2011/8

N2 - 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.

AB - 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.

UR - http://www.scopus.com/inward/record.url?scp=79961194406&partnerID=8YFLogxK

M3 - Article

SN - 1559-2324

VL - 6:8

SP - 1

EP - 5

JO - Plant Signaling and Behavior

JF - Plant Signaling and Behavior

IS - 8

ER -