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From Proteopedia
Structure of the Glutathione Transferase from Ochrobactrum anthropi in complex with glutathione
Structural highlights
FunctionGST_BRUAN Conjugation of reduced glutathione to a wide number of exogenous and endogenous hydrophobic electrophiles. Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedGSTs (glutathione transferases) are a multifunctional group of enzymes, widely distributed and involved in cellular detoxification processes. In the xenobiotic-degrading bacterium Ochrobactrum anthropi, GST is overexpressed in the presence of toxic concentrations of aromatic compounds such as 4-chlorophenol and atrazine. We have determined the crystal structure of the GST from O. anthropi (OaGST) in complex with GSH. Like other bacterial GSTs, OaGST belongs to the Beta class and shows a similar binding pocket for GSH. However, in contrast with the structure of Proteus mirabilis GST, GSH is not covalently bound to Cys10, but is present in the thiolate form. In our investigation of the structural basis for GSH stabilization, we have identified a conserved network of hydrogen-bond interactions, mediated by the presence of a structural water molecule that links Ser11 to Glu198. Partial disruption of this network, by mutagenesis of Ser11 to alanine, increases the K(m) for GSH 15-fold and decreases the catalytic efficiency 4-fold, even though Ser11 is not involved in GSH binding. Thermal- and chemical-induced unfolding studies point to a global effect of the mutation on the stability of the protein and to a central role of these residues in zippering the terminal helix of the C-terminal domain to the starting helix of the N-terminal domain. Role of Ser11 in the stabilization of the structure of Ochrobactrum anthropi glutathione transferase.,Federici L, Masulli M, Bonivento D, Di Matteo A, Gianni S, Favaloro B, Di Ilio C, Allocati N Biochem J. 2007 Apr 15;403(2):267-74. PMID:17223798[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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