2qz2 is a 1 chain structure with sequence from Aspergillus niger. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
XYNA_ASPNG Endo-1,4-beta-xylanase involved in the hydrolysis of xylan, a major structural heterogeneous polysaccharide found in plant biomass representing the second most abundant polysaccharide in the biosphere, after cellulose.
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 PubMed
GH 11 (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 into the protein-ligand interactions of the glycone as well as the aglycone subsites of these enzymes, catalytically incompetent mutants of the 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 aglycone subsites clearly adopt a different conformation upon substrate binding, allowed us to identify the residues important for substrate binding in the aglycone 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.
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. 2008 Feb 15;410(1):71-9. PMID:17983355[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
↑Vandermarliere E, Bourgois TM, Rombouts S, Van Campenhout S, Volckaert G, Strelkov SV, Delcour JA, Rabijns A, Courtin CM. 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. Biochem J. 2008 Feb 15;410(1):71-9. PMID:17983355 doi:10.1042/BJ20071128
