Structural highlights
Function
[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
The crystal structure of endo-1,4-beta-xylanase I from Aspergillus niger has been solved by molecular replacement and was refined to 2.4 A resolution. The final R-factor for all data from 6 to 2.4 A is 17.9%. The A. niger xylanase has a characteristic fold which is unique for family G xylanases (root-mean-square deviation = 1.1 A to Trichoderma reesei xylanase I, which has 53% sequence identity). It consists of a single domain composed predominantly of beta-strands. Two beta-sheets are twisted around a deep, long cleft, which is lined with many aromatic amino acid residues and is large enough to accommodate at least four xylose residues. The two conserved glutamate residues, Glu79 and Glu170, which are likely to be involved in catalysis, reach into this cleft from opposite sides. A niger xylanase I is of particular commercial interest because of its low pH optimum. A model is proposed which explains this low pH optimum compared to other members of xylanase family G.
Three-dimensional structure of Endo-1,4-beta-xylanase I from Aspergillus niger: molecular basis for its low pH optimum.,Krengel U, Dijkstra BW J Mol Biol. 1996 Oct 18;263(1):70-8. PMID:8890913[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Krengel U, Dijkstra BW. Three-dimensional structure of Endo-1,4-beta-xylanase I from Aspergillus niger: molecular basis for its low pH optimum. J Mol Biol. 1996 Oct 18;263(1):70-8. PMID:8890913 doi:http://dx.doi.org/10.1006/jmbi.1996.0556
