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4qdn
From Proteopedia
(Difference between revisions)
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| - | ''' | + | ==Crystal Structure of the endo-beta-N-acetylglucosaminidase from Thermotoga maritima== |
| + | <StructureSection load='4qdn' size='340' side='right' caption='[[4qdn]], [[Resolution|resolution]] 1.70Å' scene=''> | ||
| + | == Structural highlights == | ||
| + | <table><tr><td colspan='2'>[[4qdn]] is a 1 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4QDN OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4QDN FirstGlance]. <br> | ||
| + | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=MPD:(4S)-2-METHYL-2,4-PENTANEDIOL'>MPD</scene>, <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</scene></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=4qdn FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4qdn OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4qdn RCSB], [http://www.ebi.ac.uk/pdbsum/4qdn PDBsum]</span></td></tr> | ||
| + | </table> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | Members of the GH73 glycosidase family cleave the beta-1,4-glycosidic bond between the N-acetylglucosaminyl (GlcNAc) and N-acetylmuramyl (MurNAc) moieties in bacterial peptidoglycan. A catalytic mechanism has been proposed for members FlgJ, Auto, AcmA and Atl(WM) and the structural analysis of FlgJ and Auto revealed a conserved alpha/beta fold reminiscent of the distantly-related GH23 lysozyme. Comparison of the active site residues reveals variability in the nature of the catalytic general base suggesting two distinct catalytic mechanisms: an inverting mechanism involving two distant glutamate residues and a substrate-assisted mechanism involving anchimeric assistance by the C2-acetamido group of the GlcNAc moiety. Herein, we present the biochemical characterization and crystal structure of TM0633 from the hyperthermophilic bacterium Thermotoga maritima. TM0633 adopts the alpha/beta fold of the family and displays beta-N-acetylglucosaminidase activity on intact peptidoglycan sacculi. Site-directed mutagenesis identifies Glu34, Glu65 and Tyr118 as important residues for catalysis. A thorough bioinformatic analysis of the GH73 sequences identified five phylogenetic clusters. TM0633, FlgJ and Auto belong to a group of three clusters that conserve two carboxylate residues involved in a classical inverting acid-base mechanism. Members of the other two clusters lack a conserved catalytic general base supporting a substrate-assisted mechanism. Molecular modeling of representative members from each cluster suggests that variability in length of the beta-hairpin region above the active site confers ligand binding specificity and modulates the catalytic mechanisms within the GH73 family. | ||
| - | + | Structural and biochemical characterization of the beta-N-acetylglucosaminidase from Thermotoga maritima: toward rationalization of mechanistic knowledge in the GH73 family.,Lipski A, Herve M, Lombard V, Nurizzo D, Mengin-Lecreulx D, Bourne Y, Vincent F Glycobiology. 2014 Oct 24. pii: cwu113. PMID:25344445<ref>PMID:25344445</ref> | |
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | + | </div> | |
| - | + | == References == | |
| + | <references/> | ||
| + | __TOC__ | ||
| + | </StructureSection> | ||
| + | [[Category: Bourne, Y]] | ||
| + | [[Category: Lipski, A]] | ||
| + | [[Category: Nurizzo, D]] | ||
| + | [[Category: Vincent, F]] | ||
| + | [[Category: Bacterial peptidoglycan hydrolysis]] | ||
| + | [[Category: Glycoside hydrolase]] | ||
| + | [[Category: Hydrolase]] | ||
| + | [[Category: Inverting mechanism]] | ||
| + | [[Category: Typical lysozyme alpha-beta fold with only the alpha-lobe]] | ||
Revision as of 06:55, 12 November 2014
Crystal Structure of the endo-beta-N-acetylglucosaminidase from Thermotoga maritima
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