Conjugation of reduced glutathione to a wide number of exogenous and endogenous hydrophobic electrophiles. The olfactory GST may be crucial for the acuity of the olfactory process (PubMed:8110735, PubMed:8664265). Participates in the formation of novel hepoxilin regioisomers (By similarity). glutathione + RX = a halide anion + an S-substituted glutathione + H(+) glutathione + prostaglandin A2 = prostaglandin A2-S-(R)-glutathione glutathione + prostaglandin J2 = prostaglandin J2-S-(R)-glutathione glutathione + prostaglandin J2 = prostaglandin J2-S-(S)-glutathione glutathione + prostaglandin A2 = prostaglandin A2-S-(S)-glutathione 11(S)-hydroxy-14(S),15(S)-epoxy-(5Z,8Z,12E)-eicosatrienoate + glutathione = (11S,15S)-dihydroxy-14(R)-S-glutathionyl-(5Z,8Z,12E)-eicosatrienoate Homodimer or heterodimer. Yb subclass selectively binds steroid hormones. Belongs to the GST superfamily. Mu family.