5lkd
From Proteopedia
Crystal structure of the Xi glutathione transferase ECM4 from Saccharomyces cerevisiae in complex with glutathione
Structural highlights
FunctionGTO2_YEAST Active as '1-Cys' thiol transferase against beta-hydroxyethyl disulfide (HED), as dehydroascorbate reductase and as dimethylarsinic acid reductase, while not active against the standard GST substrate 1-chloro-2,4-dinitrobenzene (CDNB). May be involved in cell wall organization and biogenesis.[1] Publication Abstract from PubMedGlutathionyl-hydroquinone reductases (GHRs) belong to the recently characterized Xi-class of glutathione transferases (GSTXs) according to unique structural properties and are present in all but animal kingdoms. The GHR ScECM4 from the yeast Saccharomyces cerevisiae has been studied since 1997 when it was found to be potentially involved in cell-wall biosynthesis. Up to now and in spite of biological studies made on this enzyme, its physiological role remains challenging. The work here reports its crystallographic study. In addition to exhibiting the general GSTX structural features, ScECM4 shows extensions including a huge loop which contributes to the quaternary assembly. These structural extensions are probably specific to Saccharomycetaceae. Soaking of ScECM4 crystals with GS-menadione results in a structure where glutathione forms a mixed disulfide bond with the cysteine 46. Solution studies confirm that ScECM4 has reductase activity for GS-menadione in presence of glutathione. Moreover, the high resolution structures allowed us to propose new roles of conserved residues of the active site to assist the cysteine 46 during the catalytic act. Crystal Structure of Saccharomyces cerevisiae ECM4, a Xi-Class Glutathione Transferase that Reacts with Glutathionyl-(hydro)quinones.,Schwartz M, Didierjean C, Hecker A, Girardet JM, Morel-Rouhier M, Gelhaye E, Favier F PLoS One. 2016 Oct 13;11(10):e0164678. doi: 10.1371/journal.pone.0164678., eCollection 2016. PMID:27736955[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|