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| | ==Crystal Structure Analysis of the G84S EST2 mutant== | | ==Crystal Structure Analysis of the G84S EST2 mutant== |
| - | <StructureSection load='2hm7' size='340' side='right' caption='[[2hm7]], [[Resolution|resolution]] 2.00Å' scene=''> | + | <StructureSection load='2hm7' size='340' side='right'caption='[[2hm7]], [[Resolution|resolution]] 2.00Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[2hm7]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Atcc_27009 Atcc 27009]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2HM7 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2HM7 FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[2hm7]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Alicyclobacillus_acidocaldarius Alicyclobacillus acidocaldarius]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2HM7 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2HM7 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]] 2Å</td></tr> |
| - | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1evq|1evq]]</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='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Carboxylesterase Carboxylesterase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.1.1 3.1.1.1] </span></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=2hm7 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2hm7 OCA], [https://pdbe.org/2hm7 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2hm7 RCSB], [https://www.ebi.ac.uk/pdbsum/2hm7 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2hm7 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=2hm7 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2hm7 OCA], [http://pdbe.org/2hm7 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=2hm7 RCSB], [http://www.ebi.ac.uk/pdbsum/2hm7 PDBsum]</span></td></tr> | + | |
| | </table> | | </table> |
| | + | == Function == |
| | + | [https://www.uniprot.org/uniprot/Q7SIG1_ALIAC Q7SIG1_ALIAC] |
| | == Evolutionary Conservation == | | == Evolutionary Conservation == |
| | [[Image:Consurf_key_small.gif|200px|right]] | | [[Image:Consurf_key_small.gif|200px|right]] |
| | Check<jmol> | | Check<jmol> |
| | <jmolCheckbox> | | <jmolCheckbox> |
| - | <scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/hm/2hm7_consurf.spt"</scriptWhenChecked> | + | <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/hm/2hm7_consurf.spt"</scriptWhenChecked> |
| | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | | <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> |
| | <text>to colour the structure by Evolutionary Conservation</text> | | <text>to colour the structure by Evolutionary Conservation</text> |
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| | ==See Also== | | ==See Also== |
| - | *[[Carboxylesterase|Carboxylesterase]] | + | *[[Carboxylesterase 3D structures|Carboxylesterase 3D structures]] |
| | == References == | | == References == |
| | <references/> | | <references/> |
| | __TOC__ | | __TOC__ |
| | </StructureSection> | | </StructureSection> |
| - | [[Category: Atcc 27009]] | + | [[Category: Alicyclobacillus acidocaldarius]] |
| - | [[Category: Carboxylesterase]] | + | [[Category: Large Structures]] |
| - | [[Category: Alterio, V]] | + | [[Category: Alterio V]] |
| - | [[Category: Menchise, V]]
| + | [[Category: De Simone G]] |
| - | [[Category: Simone, G De]] | + | [[Category: Menchise V]] |
| - | [[Category: Alpha/beta hydrolase fold]] | + | |
| - | [[Category: Hydrolase]]
| + | |
| Structural highlights
Function
Q7SIG1_ALIAC
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Recent mutagenic and molecular modelling studies suggested a role for glycine 84 in the putative oxyanion loop of the carboxylesterase EST2 from Alicyclobacillus acidocaldarius. A 114 times decrease of the esterase catalytic activity of the G84S mutant was observed, without changes in the thermal stability. The recently solved three-dimensional (3D) structure of EST2 in complex with a HEPES molecule permitted to demonstrate that G84 (together with G83 and A156) is involved in the stabilization of the oxyanion through a hydrogen bond from its main chain NH group. The structural data in this case did not allowed us to rationalize the effect of the mutation, since this hydrogen bond was predicted to be unaltered in the mutant. Since the mutation could shed light on the role of the oxyanion loop in the HSL family, experiments to elucidate at the mechanistic level the reasons of the observed drop in k (cat) were devised. In this work, the kinetic and structural features of the G84S mutant were investigated in more detail. The optimal temperature and pH for the activity of the mutated enzyme were found significantly changed (T = 65 degrees C and pH = 5.75). The catalytic constants K (M) and V(max) were found considerably altered in the mutant, with ninefold increased K (M) and 14-fold decreased V(max), at pH 5.75. At pH 7.1, the decrease in k (cat) was much more dramatic. The measurement of kinetic constants for some steps of the reaction mechanism and the resolution of the mutant 3D structure provided evidences that the observed effects were partly due to the steric hindrance of the S84-OH group towards the ester substrate and partly to its interference with the nucleophilic attack of a water molecule on the second tetrahedral intermediate. Proteins 2007. (c) 2007 Wiley-Liss, Inc.
Functional and structural features of the oxyanion hole in a thermophilic esterase from Alicyclobacillus acidocaldarius.,Mandrich L, Menchise V, Alterio V, De Simone G, Pedone C, Rossi M, Manco G Proteins. 2007 Dec 12;. PMID:18076040[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Mandrich L, Menchise V, Alterio V, De Simone G, Pedone C, Rossi M, Manco G. Functional and structural features of the oxyanion hole in a thermophilic esterase from Alicyclobacillus acidocaldarius. Proteins. 2007 Dec 12;. PMID:18076040 doi:10.1002/prot.21877
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