1xa8
Crystal Structure Analysis of Glutathione-dependent formaldehyde-activating enzyme (Gfa)Crystal Structure Analysis of Glutathione-dependent formaldehyde-activating enzyme (Gfa)
Structural highlights
FunctionGFA_PARDE Catalyzes the condensation of formaldehyde and glutathione to S-hydroxymethylglutathione.[1] 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 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. 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[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
|
| ||||||||||||||||||