148l
From Proteopedia
(Difference between revisions)
| (20 intermediate revisions not shown.) | |||
| Line 1: | Line 1: | ||
| - | [[Image:148l.gif|left|200px]]<br /><applet load="148l" size="350" color="white" frame="true" align="right" spinBox="true" | ||
| - | caption="148l, resolution 1.90Å" /> | ||
| - | '''A COVALENT ENZYME-SUBSTRATE INTERMEDIATE WITH SACCHARIDE DISTORTION IN A MUTANT T4 LYSOZYME'''<br /> | ||
| - | == | + | ==A COVALENT ENZYME-SUBSTRATE INTERMEDIATE WITH SACCHARIDE DISTORTION IN A MUTANT T4 LYSOZYME== |
| + | <StructureSection load='148l' size='340' side='right'caption='[[148l]], [[Resolution|resolution]] 1.90Å' scene=''> | ||
| + | == Structural highlights == | ||
| + | <table><tr><td colspan='2'>[[148l]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] and [https://en.wikipedia.org/wiki/Escherichia_virus_T4 Escherichia virus T4]. The September 2000 RCSB PDB [https://pdb.rcsb.org/pdb/static.do?p=education_discussion/molecule_of_the_month/index.html Molecule of the Month] feature on ''Lysozyme'' by David S. Goodsell is [https://dx.doi.org/10.2210/rcsb_pdb/mom_2000_9 10.2210/rcsb_pdb/mom_2000_9]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=148L OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=148L 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]] 1.9Å</td></tr> | ||
| + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=API:2,6-DIAMINOPIMELIC+ACID'>API</scene>, <scene name='pdbligand=BME:BETA-MERCAPTOETHANOL'>BME</scene>, <scene name='pdbligand=DAL:D-ALANINE'>DAL</scene>, <scene name='pdbligand=FGA:GAMMA-D-GLUTAMIC+ACID'>FGA</scene>, <scene name='pdbligand=MUB:N-ACETYLMURAMIC+ACID'>MUB</scene>, <scene name='pdbligand=NAG:N-ACETYL-D-GLUCOSAMINE'>NAG</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=148l FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=148l OCA], [https://pdbe.org/148l PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=148l RCSB], [https://www.ebi.ac.uk/pdbsum/148l PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=148l ProSAT]</span></td></tr> | ||
| + | </table> | ||
| + | == Function == | ||
| + | [https://www.uniprot.org/uniprot/ENLYS_BPT4 ENLYS_BPT4] Endolysin with lysozyme activity that degrades host peptidoglycans and participates with the holin and spanin proteins in the sequential events which lead to the programmed host cell lysis releasing the mature viral particles. Once the holin has permeabilized the host cell membrane, the endolysin can reach the periplasm and break down the peptidoglycan layer.<ref>PMID:22389108</ref> | ||
| + | == 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/48/148l_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=148l ConSurf]. | ||
| + | <div style="clear:both"></div> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
The glycosyl-enzyme intermediate in lysozyme action has long been considered to be an oxocarbonium ion, although precedent from other glycosidases and theoretical considerations suggest it should be a covalent enzyme-substrate adduct. The mutation of threonine 26 to glutamic acid in the active site cleft of phage T4 lysozyme (T4L) produced an enzyme that cleaved the cell wall of Escherichia coli but left the product covalently bound to the enzyme. The crystalline complex was nonisomorphous with wild-type T4L, and analysis of its structure showed a covalent linkage between the product and the newly introduced glutamic acid 26. The covalently linked sugar ring was substantially distorted, suggesting that distortion of the substrate toward the transition state is important for catalysis, as originally proposed by Phillips. It is also postulated that the adduct formed by the mutant is an intermediate, consistent with a double displacement mechanism of action in which the glycosidic linkage is cleaved with retention of configuration as originally proposed by Koshland. The peptide part of the cell wall fragment displays extensive hydrogen-bonding interactions with the carboxyl-terminal domain of the enzyme, consistent with previous studies of mutations in T4L. | The glycosyl-enzyme intermediate in lysozyme action has long been considered to be an oxocarbonium ion, although precedent from other glycosidases and theoretical considerations suggest it should be a covalent enzyme-substrate adduct. The mutation of threonine 26 to glutamic acid in the active site cleft of phage T4 lysozyme (T4L) produced an enzyme that cleaved the cell wall of Escherichia coli but left the product covalently bound to the enzyme. The crystalline complex was nonisomorphous with wild-type T4L, and analysis of its structure showed a covalent linkage between the product and the newly introduced glutamic acid 26. The covalently linked sugar ring was substantially distorted, suggesting that distortion of the substrate toward the transition state is important for catalysis, as originally proposed by Phillips. It is also postulated that the adduct formed by the mutant is an intermediate, consistent with a double displacement mechanism of action in which the glycosidic linkage is cleaved with retention of configuration as originally proposed by Koshland. The peptide part of the cell wall fragment displays extensive hydrogen-bonding interactions with the carboxyl-terminal domain of the enzyme, consistent with previous studies of mutations in T4L. | ||
| - | + | A covalent enzyme-substrate intermediate with saccharide distortion in a mutant T4 lysozyme.,Kuroki R, Weaver LH, Matthews BW Science. 1993 Dec 24;262(5142):2030-3. PMID:8266098<ref>PMID:8266098</ref> | |
| - | + | ||
| - | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |
| - | + | </div> | |
| - | + | <div class="pdbe-citations 148l" style="background-color:#fffaf0;"></div> | |
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ||
| - | + | ==See Also== | |
| + | *[[Lysozyme 3D structures|Lysozyme 3D structures]] | ||
| + | == References == | ||
| + | <references/> | ||
| + | __TOC__ | ||
| + | </StructureSection> | ||
| + | [[Category: Escherichia coli]] | ||
| + | [[Category: Escherichia virus T4]] | ||
| + | [[Category: Large Structures]] | ||
| + | [[Category: Lysozyme]] | ||
| + | [[Category: RCSB PDB Molecule of the Month]] | ||
| + | [[Category: Kuroki R]] | ||
| + | [[Category: Matthews BW]] | ||
| + | [[Category: Weaver LH]] | ||
Current revision
A COVALENT ENZYME-SUBSTRATE INTERMEDIATE WITH SACCHARIDE DISTORTION IN A MUTANT T4 LYSOZYME
| |||||||||||
