2bnj: Difference between revisions
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< | ==The xylanase TA from Thermoascus aurantiacus utilizes arabinose decorations of xylan as significant substrate specificity determinants.== | ||
<StructureSection load='2bnj' size='340' side='right'caption='[[2bnj]], [[Resolution|resolution]] 1.60Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[2bnj]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Thermoascus_aurantiacus Thermoascus aurantiacus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2BNJ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2BNJ FirstGlance]. <br> | |||
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.6Å</td></tr> | |||
--> | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=AHR:ALPHA-L-ARABINOFURANOSE'>AHR</scene>, <scene name='pdbligand=FER:3-(4-HYDROXY-3-METHOXYPHENYL)-2-PROPENOIC+ACID'>FER</scene>, <scene name='pdbligand=PCA:PYROGLUTAMIC+ACID'>PCA</scene>, <scene name='pdbligand=XYP:BETA-D-XYLOPYRANOSE'>XYP</scene></td></tr> | ||
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2bnj FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2bnj OCA], [https://pdbe.org/2bnj PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2bnj RCSB], [https://www.ebi.ac.uk/pdbsum/2bnj PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2bnj ProSAT]</span></td></tr> | |||
</table> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/XYNA_THEAU XYNA_THEAU] | |||
== Evolutionary Conservation == | |||
== | [[Image:Consurf_key_small.gif|200px|right]] | ||
Check<jmol> | |||
<jmolCheckbox> | |||
<scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/bn/2bnj_consurf.spt"</scriptWhenChecked> | |||
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | |||
<text>to colour the structure by Evolutionary Conservation</text> | |||
</jmolCheckbox> | |||
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=2bnj ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
Xylan, which is a key component of the plant cell wall, consists of a backbone of beta-1,4-linked xylose residues that are decorated with arabinofuranose, acetyl, 4-O-methyl d-glucuronic acid and ferulate. The backbone of xylan is hydrolysed by endo-beta1,4-xylanases (xylanases); however, it is unclear whether the various side-chains of the polysaccharide are utilized by these enzymes as significant substrate specificity determinants. To address this question we have determined the crystal structure of a family 10 xylanase from Thermoascus aurantiacus, in complex with xylobiose containing an arabinofuranosyl-ferulate side-chain. We show that the distal glycone subsite of the enzyme makes extensive direct and indirect interactions with the arabinose side-chain, while the ferulate moiety is solvent-exposed. Consistent with the 3D structural data, the xylanase displays fourfold more activity against xylotriose in which the non-reducing moiety is linked to an arabinose side-chain, compared to the undecorated form of the oligosacchairde. These data indicate that the sugar decorations of xylans in the T.aurantiacus family 10 xylanase, rather than simply being accommodated, can be significant substrate specificity determinants. | Xylan, which is a key component of the plant cell wall, consists of a backbone of beta-1,4-linked xylose residues that are decorated with arabinofuranose, acetyl, 4-O-methyl d-glucuronic acid and ferulate. The backbone of xylan is hydrolysed by endo-beta1,4-xylanases (xylanases); however, it is unclear whether the various side-chains of the polysaccharide are utilized by these enzymes as significant substrate specificity determinants. To address this question we have determined the crystal structure of a family 10 xylanase from Thermoascus aurantiacus, in complex with xylobiose containing an arabinofuranosyl-ferulate side-chain. We show that the distal glycone subsite of the enzyme makes extensive direct and indirect interactions with the arabinose side-chain, while the ferulate moiety is solvent-exposed. Consistent with the 3D structural data, the xylanase displays fourfold more activity against xylotriose in which the non-reducing moiety is linked to an arabinose side-chain, compared to the undecorated form of the oligosacchairde. These data indicate that the sugar decorations of xylans in the T.aurantiacus family 10 xylanase, rather than simply being accommodated, can be significant substrate specificity determinants. | ||
A family 10 Thermoascus aurantiacus xylanase utilizes arabinose decorations of xylan as significant substrate specificity determinants.,Vardakou M, Flint J, Christakopoulos P, Lewis RJ, Gilbert HJ, Murray JW J Mol Biol. 2005 Oct 7;352(5):1060-7. PMID:16140328<ref>PMID:16140328</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
<div class="pdbe-citations 2bnj" style="background-color:#fffaf0;"></div> | |||
[[Category: | == References == | ||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Large Structures]] | |||
[[Category: Thermoascus aurantiacus]] | [[Category: Thermoascus aurantiacus]] | ||
[[Category: Christakopoulos | [[Category: Christakopoulos P]] | ||
[[Category: Flint | [[Category: Flint J]] | ||
[[Category: Gilbert | [[Category: Gilbert HJ]] | ||
[[Category: Lewis | [[Category: Lewis RJ]] | ||
[[Category: Murray | [[Category: Murray JW]] | ||
[[Category: Vardakou | [[Category: Vardakou M]] | ||