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1gsd
From Proteopedia
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GLUTATHIONE TRANSFERASE A1-1 IN UNLIGANDED FORM
Overview
BACKGROUND: Glutathione transferases (GSTs) constitute a family of, isoenzymes that catalyze the conjugation of the tripeptide glutathione, with a wide variety of hydrophobic compounds bearing an electrophilic, functional group. Recently, a number of X-ray structures have been, reported which have defined both the glutathione- and the, substrate-binding sites in these enzymes. The structure of the, glutathione-free enzyme from a mammalian source has not, however, been, reported previously. RESULTS: We have solved structures of a human, alpha-class GST, isoenzyme A1-1, both in the unliganded form and in, complexes with the inhibitor ethacrynic acid and its glutathione, conjugate. These structures have been refined to resolutions of 2.5 A, 2.7, A and 2.0 A respectively. Both forms of the inhibitor are clearly present, in the associated electron density. CONCLUSIONS: The major differences, among the three structures reported here involve the C-terminal, alpha-helix, which is a characteristic of the alpha-class enzyme. This, helix forms a lid over the active site when the hydrophobic substrate, binding site (H-site) is occupied but it is otherwise disordered., Ethacrynic acid appears to bind in a non-productive mode in the absence of, the coenzyme glutathione.
About this Structure
1GSD is a Single protein structure of sequence from Homo sapiens. Active as Glutathione transferase, with EC number 2.5.1.18 Full crystallographic information is available from OCA.
Reference
Structural analysis of human alpha-class glutathione transferase A1-1 in the apo-form and in complexes with ethacrynic acid and its glutathione conjugate., Cameron AD, Sinning I, L'Hermite G, Olin B, Board PG, Mannervik B, Jones TA, Structure. 1995 Jul 15;3(7):717-27. PMID:8591048
Page seeded by OCA on Mon Nov 12 17:08:38 2007
