Conjugation of reduced glutathione to a wide number of exogenous and endogenous hydrophobic electrophiles. Has substantial activity toward aflatoxin B1-8,9-epoxide. glutathione + RX = a halide anion + an S-substituted glutathione + H(+) Heterodimer of YC1 and YC2. Liver, nasal mucosa and epididymis. Liver from adult female rats contains about 10-fold greater levels of YC2 than is found in liver from adult male rats. By ethoxyquin, oltipraz, butylated hydroxyanisole, and phenobarbitol. Belongs to the GST superfamily. Alpha family.