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| | ==Crystal structure of lytic transglycosylase MltE from Eschericha coli== | | ==Crystal structure of lytic transglycosylase MltE from Eschericha coli== |
| - | <StructureSection load='3t36' size='340' side='right' caption='[[3t36]], [[Resolution|resolution]] 2.25Å' scene=''> | + | <StructureSection load='3t36' size='340' side='right'caption='[[3t36]], [[Resolution|resolution]] 2.25Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[3t36]] is a 5 chain structure with sequence from [http://en.wikipedia.org/wiki/Ecoli Ecoli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3T36 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3T36 FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[3t36]] is a 5 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli_K-12 Escherichia coli K-12]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3T36 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3T36 FirstGlance]. <br> |
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr> | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.25Å</td></tr> |
| - | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[3t1z|3t1z]], [[3t21|3t21]], [[3t4i|3t4i]]</td></tr>
| + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr> |
| - | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">emtA, mltE, sltZ, ycgP, b1193, JW5821 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=83333 ECOLI])</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=3t36 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3t36 OCA], [https://pdbe.org/3t36 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3t36 RCSB], [https://www.ebi.ac.uk/pdbsum/3t36 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3t36 ProSAT]</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=3t36 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3t36 OCA], [http://pdbe.org/3t36 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=3t36 RCSB], [http://www.ebi.ac.uk/pdbsum/3t36 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=3t36 ProSAT]</span></td></tr> | + | |
| | </table> | | </table> |
| | == Function == | | == Function == |
| - | [[http://www.uniprot.org/uniprot/EMTA_ECOLI EMTA_ECOLI]] Murein-degrading enzyme. May play a role in recycling of muropeptides during cell elongation and/or cell division. Preferentially cleaves at a distance of more than two disaccharide units from the ends of the glycan chain. Prefers cross-linked murein in vivo. | + | [https://www.uniprot.org/uniprot/EMTA_ECOLI EMTA_ECOLI] Murein-degrading enzyme. May play a role in recycling of muropeptides during cell elongation and/or cell division. Preferentially cleaves at a distance of more than two disaccharide units from the ends of the glycan chain. Prefers cross-linked murein in vivo. |
| - | <div style="background-color:#fffaf0;">
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| - | == Publication Abstract from PubMed ==
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| - | The lytic transglycosylase MltE from Escherichia coli is a periplasmic, outer membrane-attached enzyme that cleaves the beta-1,4-glycosidic bonds between N-acetylmuramic acid and N-acetylglucosamine residues in the cell wall peptidoglycan, producing 1,6-anhydromuropeptides. Here we report three crystal structures of MltE: in a substrate-free state, in a binary complex with chitopentaose, and in a ternary complex with the glycopeptide inhibitor bulgecin A and the murodipeptide N-acetylglucosaminyl-N-acetylmuramyl-l-Ala-d-Glu. The substrate-bound structures allowed a detailed analysis of the saccharide-binding interactions in six subsites of the peptidoglycan-binding groove (subsites -4 to +2) and, combined with site-directed mutagenesis analysis, confirmed the role of Glu64 as catalytic acid/base. The structures permitted the precise modeling of a short glycan strand of eight saccharide residues, providing evidence for two additional subsites (+3 and +4) and revealing the productive conformational state of the substrate at subsites -1 and +1, where the glycosidic bond is cleaved. Full accessibility of the peptidoglycan-binding groove and preferential binding of an N-acetylmuramic acid residue in a (4)C(1) chair conformation at subsite +2 explain why MltE shows only endo- and no exo-specific activity toward glycan strands. The results further indicate that catalysis of glycosidic bond cleavage by MltE proceeds via distortion toward a sofa-like conformation of the N-acetylmuramic acid sugar ring at subsite -1 and by anchimeric assistance of the sugar's N-acetyl group, as shown previously for the lytic transglycosylases Slt70 and MltB.
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| - | On the Mechanism of Peptidoglycan Binding and Cleavage by the endo-Specific Lytic Transglycosylase MltE from Escherichia coli.,Fibriansah G, Gliubich FI, Thunnissen AM Biochemistry. 2012 Oct 30. PMID:23075328<ref>PMID:23075328</ref>
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| - | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br>
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| - | </div>
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| - | <div class="pdbe-citations 3t36" style="background-color:#fffaf0;"></div>
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| - | == References ==
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| - | <references/>
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| | __TOC__ | | __TOC__ |
| | </StructureSection> | | </StructureSection> |
| - | [[Category: Ecoli]] | + | [[Category: Escherichia coli K-12]] |
| - | [[Category: Fibriansah, G]] | + | [[Category: Large Structures]] |
| - | [[Category: Gliubich, F I]] | + | [[Category: Fibriansah G]] |
| - | [[Category: Thunnissen, A M.W H]] | + | [[Category: Gliubich FI]] |
| - | [[Category: Goose type lysozyme-like structure]] | + | [[Category: Thunnissen A-MWH]] |
| - | [[Category: Lyase]]
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| - | [[Category: Lytic transglycosylase]]
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