View source for 6haa


==Structure of a covalent complex of endo-Xyloglucanase from Cellvibrio japonicus after reacting with XXXG(2F)-beta-DNP==
<StructureSection load='6haa' size='340' side='right' caption='[[6haa]], [[Resolution|resolution]] 1.70&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6haa]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Celju Celju]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6HAA OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6HAA FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=1PE:PENTAETHYLENE+GLYCOL'>1PE</scene>, <scene name='pdbligand=BGC:BETA-D-GLUCOSE'>BGC</scene>, <scene name='pdbligand=G2F:2-DEOXY-2-FLUORO-ALPHA-D-GLUCOPYRANOSE'>G2F</scene>, <scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=MES:2-(N-MORPHOLINO)-ETHANESULFONIC+ACID'>MES</scene>, <scene name='pdbligand=PGE:TRIETHYLENE+GLYCOL'>PGE</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene>, <scene name='pdbligand=XYS:XYLOPYRANOSE'>XYS</scene></td></tr>
<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">cel5D, CJA_3010 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=498211 CELJU])</td></tr>
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Xyloglucan-specific_endo-beta-1,4-glucanase Xyloglucan-specific endo-beta-1,4-glucanase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.151 3.2.1.151] </span></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6haa FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6haa OCA], [http://pdbe.org/6haa PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6haa RCSB], [http://www.ebi.ac.uk/pdbsum/6haa PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6haa ProSAT]</span></td></tr>
</table>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Xyloglucan (XyG) is a complex polysaccharide that is ubiquitous and often abundant in the cell walls of terrestrial plants. XyG metabolism is therefore a key component of the global carbon cycle, and hence XyG enzymology is of significant fundamental and applied importance in biomass conversion. To facilitate structure-function analyses of XyG-specific endo-glucanases, we have synthesized a 2',4'-dinitrophenyl 2-deoxy-2-fluoro-beta-glycoside mechanism-based inhibitor based on the highly branched XyG repeating motif XXXG (Xyl3Glc4: ([alpha-d-Xylp-(1--&gt;6)]-beta-d-Glcp-(1--&gt;4)-[alpha-d-Xylp-(1--&gt;6)]-beta-d-Glcp-(1 --&gt;4)-[alpha-d-Xylp-(1--&gt;6)]-beta-d-Glcp-(1--&gt;4)-d-Glcp. Key steps in the chemo-enzymatic synthesis included selective enzyme hydrolysis of XyG polysaccharide to produce the core heptasaccharide, per-O-acetylation, alpha-bromination, reductive glycal formation, electrophilic fluorination, SNAr glycosylation, and Zemplen deprotection. The resulting compound, XXXG(2F)-beta-DNP, specifically labelled the active sites of several endo-(xylo)glucanases by accumulation of a covalent glycosyl-enzyme intermediate, as revealed by intact protein mass spectrometry. Crystallography of a complex with a Cellvibrio japonicus Glycoside Hydrolase Family 5 (GH5) endo-xyloglucanase corroborated the covalent nature of the intermediate, and further revealed the anticipated specificity for the catalytic nucleophile of this anomeric-configuration-retaining glycosidase. This specificity complements that of an analogous XXXG N-bromoacetylglycosylamine inhibitor, which labelled the catalytic acid-base sidechain in the same enzyme [Attia, et al., Biotechnol. Biofuels, 2018, 11, 45]. We anticipate that these inhibitors may find continued use in mechanistic analyses of endo-(xylo)glucanases from diverse GH families.

Synthesis and application of a highly branched, mechanism-based 2-deoxy-2-fluoro-oligosaccharide inhibitor of endo-xyloglucanases.,Jain N, Attia MA, Offen WA, Davies GJ, Brumer H Org Biomol Chem. 2018 Nov 21;16(45):8732-8741. doi: 10.1039/c8ob02250j. PMID:30387796<ref>PMID:30387796</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6haa" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Celju]]
[[Category: Xyloglucan-specific endo-beta-1,4-glucanase]]
[[Category: Davies, G J]]
[[Category: Offen, W]]
[[Category: Covalent inhibitor]]
[[Category: Glycoside hydrolase]]
[[Category: Hydrolase]]
[[Category: Xyloglucan]]