Active as '1-Cys' thiol transferase against beta-hydroxyethyl disulfide (HED), as dehydroascorbate reductase and as dimethylarsinic acid reductase, while not active against the standard GST substrate 1-chloro-2,4-dinitrobenzene (CDNB). May be involved in cell wall organization and biogenesis (By similarity). glutathione + RX = a halide anion + an S-substituted glutathione + H(+) 2 glutathione + L-dehydroascorbate = glutathione disulfide + L-ascorbate Belongs to the GST superfamily. Omega family.