1e6b
Crystal structure of a Zeta class glutathione S-transferase from Arabidopsis thalianaCrystal structure of a Zeta class glutathione S-transferase from Arabidopsis thaliana
Structural highlights
Function[GSTZ1_ARATH] Acts a maleylacetone isomerase. Also catalyzes the glutathione-dependent dehalogenation of dichloroacetic acid to glyoxylic acid. In vitro, possesses glutathione peroxidase activity toward cumene hydroperoxide and linoleic acid-13-hydroperoxide. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe cis-trans isomerisation of maleylacetoacetate to fumarylacetoacetate is the penultimate step in the tyrosine/phenylalanine catabolic pathway and has recently been shown to be catalysed by glutathione S-transferase enzymes belonging to the zeta class. Given this primary metabolic role it is unsurprising that zeta class glutathione S-transferases are well conserved over a considerable period of evolution, being found in vertebrates, plants, insects and fungi. The structure of this glutathione S-transferase, cloned from Arabidopsis thaliana, has been solved by single isomorphous replacement with anomalous scattering and refined to a final crystallographic R-factor of 19.6% using data from 25.0 A to 1.65 A. The zeta class enzyme adopts the canonical glutathione S-transferase fold and forms a homodimer with each subunit consisting of 221 residues. In agreement with structures of glutathione S-transferases from the theta and phi classes, a serine residue (Ser17) is present in the active site, at a position that would allow it to stabilise the thiolate anion of glutathione. Site-directed mutagenesis of this residue confirms its importance in catalysis. In addition, the role of a highly conserved cysteine residue (Cys19) present in the active site of the zeta class glutathione S-transferase enzymes is discussed. The structure of a zeta class glutathione S-transferase from Arabidopsis thaliana: characterisation of a GST with novel active-site architecture and a putative role in tyrosine catabolism.,Thom R, Dixon DP, Edwards R, Cole DJ, Lapthorn AJ J Mol Biol. 2001 May 18;308(5):949-62. PMID:11352584[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|
| ||||||||||||||||||