1x6m

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Revision as of 03:44, 21 November 2007

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spinqualitylabelsall models 1x6m, resolution 2.35Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

Crystal structure of the glutathione-dependent formaldehyde-activating enzyme (Gfa)

Overview

The crystal structures of glutathione-dependent formaldehyde-activating, enzyme (Gfa) from Paracoccus denitrificans, which catalyzes the formation, of S-hydroxymethylglutathione from formaldehyde and glutathione, and its, complex with glutathione (Gfa-GTT) have been determined. Gfa has a new, fold with two zinc-sulfur centers, one that is structural (zinc, tetracoordinated) and one catalytic (zinc apparently tricoordinated). In, Gfa-GTT, the catalytic zinc is displaced due to disulfide bond formation, of glutathione with one of the zinc-coordinating cysteines. Soaking, crystals of Gfa-GTT with formaldehyde restores the holoenzyme., Accordingly, the displaced zinc forms a complex by scavenging formaldehyde, and glutathione. The activation of formaldehyde and of glutathione in this, zinc complex favors the final nucleophilic addition, followed by, relocation of zinc in the catalytic site. Therefore, the structures of Gfa, and Gfa-GTT draw the critical association between a dynamic zinc redox, switch and a nucleophilic addition as a new facet of the redox activity of, zinc-sulfur sites.

About this Structure

1X6M is a Single protein structure of sequence from Paracoccus denitrificans with ZN, SO4 and GOL as ligands. Full crystallographic information is available from OCA.

Reference

A dynamic zinc redox switch., Neculai AM, Neculai D, Griesinger C, Vorholt JA, Becker S, J Biol Chem. 2005 Jan 28;280(4):2826-30. Epub 2004 Nov 17. PMID:15548539

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