2qz2
From Proteopedia
OCA (Talk | contribs)
(New page: 200px<br /><applet load="2qz2" size="350" color="white" frame="true" align="right" spinBox="true" caption="2qz2, resolution 2.80Å" /> '''Crystal structure of...)
Next diff →
Revision as of 09:27, 23 January 2008
|
Crystal structure of a glycoside hydrolase family 11 xylanase from Aspergillus niger in complex with xylopentaose
Overview
Glycoside hydrolase family 11 xylanases are predominant enzymes in the, hydrolysis of heteroxylan, an abundant structural polysaccharide in the, plant cell wall. To gain more insight in the protein-ligand interactions, of the glycon as well as the aglycon subsites of these enzymes, catalytically incompetent mutants of Bacillus subtilis and Aspergillus, niger xylanases were crystallized, soaked with xylo-oligosaccharides and, subjected to X-ray analysis. For both xylanases, there was clear density, for xylose residues in the -1 and -2 subsites. In addition, for the B., subtilis xylanase, there was also density for xylose residues in the -3, and +1 subsite showing the spanning of the -1/+1 subsites. These results, together with the observation that some residues in the aglycon subsites, clearly adopt a different conformation upon substrate binding allowed us, to identify the residues important for substrate binding in the aglycon, subsites. In addition to substrate binding in the active site of the, enzymes, the existence of an unproductive second ligand binding site, located on the surface of both the B. subtilis and A. niger xylanases was, observed. This extra binding site may have a function similar to the, separate carbohydrate binding modules of other glycoside hydrolase, families.
About this Structure
2QZ2 is a Single protein structure of sequence from Aspergillus niger with and as ligands. Active as Endo-1,4-beta-xylanase, with EC number 3.2.1.8 Full crystallographic information is available from OCA.
Reference
Crystallographic analysis shows substrate binding at the -3 to +1 active site subsites and at the surface of glycoside hydrolase family 11 endo-1,4-beta-xylanases., Vandermarliere E, Bourgois TM, Rombouts S, Van Campenhout S, Volckaert G, Strelkov SV, Delcour JA, Rabijns A, Courtin CM, Biochem J. 2007 Nov 6;. PMID:17983355
Page seeded by OCA on Wed Jan 23 11:27:48 2008
