GSTZ1 is part of the glutathione S-transferase super-family which encodes multifunctional enzymes vital in the detoxification of electrophilic molecules， including carcinogens， mutagens， and several therapeutic drugs， by conjugation with glutathione. GSTZ1 participates in the catabolism of phenylalanine and tyrosine. Thus defects in GSTZ1 cause harsh metabolic disorders including alkaptonuria， phenylketonuria and tyrosinaemia. GSTZ1 is a bifunctional protein which has minimal glutathione-conjugating activity with ethacrynic acid and 7-chloro-4-nitrobenz-2-oxa-1，3-diazole and maleylacetoacetate isomerase activity. GSTZ1 has low glutathione peroxidase activity with T-butyl and cumene hydroperoxides. GSTZ1 catalyzes the glutathione dependent oxygenation of dichloroacetic acid to glyoxylic acid.
