Zeta, a novel class of glutathione transferases in a range of species from plants to humans

• Published in: Biochemical journal 1997-12, Vol.328 (3), p.929-935
• Main Authors: Board, P.G, Baker, R.T, Chelvanayagam, G, Jermiin, L.S
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Animals; Binding Sites; Cloning, Molecular; Conserved Sequence - genetics; Dimerization; Evolution, Molecular; Glutathione - metabolism; Glutathione Peroxidase - metabolism; glutathione transferase; Glutathione Transferase - analysis; Glutathione Transferase - chemistry; Glutathione Transferase - genetics; Glutathione Transferase - metabolism; Humans; Models, Molecular; Molecular Sequence Data; Peroxides - metabolism; Phylogeny; Plants - enzymology; Recombinant Proteins - chemistry; Sequence Alignment; Sequence Analysis, DNA; Substrate Specificity; Tissue Distribution
• ISSN: 0264-6021; 1470-8728
• DOI: 10.1042/bj3280929

Sequence alignment and phylogenetic analysis has identified a new subgroup of glutathione S-transferase (GST)-like proteins from a range of species extending from plants to humans. This group has been termed the Zeta class. An atomic model of the N-terminal domain suggests that the members of the Zeta class have a similar structure to that of other GSTs, binding glutathione in a similar orientation in the G site. Recombinant human GSTZ1-1 has been expressed in Escherichia coli and characterized. The protein is a dimer composed of 24.2 kDa subunits and has minimal glutathione-conjugating activity with ethacrynic acid and 7-chloro-4-nitrobenz-2-oxa-1, 3-diazole. Although low in comparison with other GSTs, GSTZ1-1 has glutathione peroxidase activity with t-butyl and cumene hydroperoxides. The members of the Zeta class have been conserved over a long evolutionary period, suggesting that they might have a role in the metabolism of a compound that is common in many living cells.