?
C-terminal, alpha helical domain of Dehydroascorbate Reductase Glutathione S-transferase (GST) C-terminal domain family, Dehydroascorbate Reductase (DHAR) subfamily; composed of plant-specific DHARs, which are monomeric enzymes catalyzing the reduction of DHA into ascorbic acid (AsA) using glutathione as the reductant. DHAR allows plants to recycle oxidized AsA before it is lost. AsA serves as a cofactor of violaxanthin de-epoxidase in the xanthophyll cycle and as an antioxidant in the detoxification of reactive oxygen species. Because AsA is the major reductant in plants, DHAR serves to regulate their redox state. It has been suggested that a significant portion of DHAR activity is plastidic, acting to reduce the large amounts of ascorbate oxidized during hydrogen peroxide scavenging by ascorbate peroxidase. DHAR contains a conserved cysteine in its active site and in addition to its reductase activity, shows thiol transferase activity similar to glutaredoxins. |
Jiyao W et al.(2023). "The conserved domain database in 2023.",