4e97: Difference between revisions
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[[ | ==T4 Lysozyme L99A/M102H with 2-Mercaptoethanol Bound== | ||
<StructureSection load='4e97' size='340' side='right' caption='[[4e97]], [[Resolution|resolution]] 1.30Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[4e97]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Enterobacteria_phage_t4 Enterobacteria phage t4]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4E97 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4E97 FirstGlance]. <br> | |||
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=ACT:ACETATE+ION'>ACT</scene>, <scene name='pdbligand=BME:BETA-MERCAPTOETHANOL'>BME</scene>, <scene name='pdbligand=HED:2-HYDROXYETHYL+DISULFIDE'>HED</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr> | |||
<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">E ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=10665 Enterobacteria phage T4])</td></tr> | |||
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Lysozyme Lysozyme], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.2.1.17 3.2.1.17] </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=4e97 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4e97 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4e97 RCSB], [http://www.ebi.ac.uk/pdbsum/4e97 PDBsum]</span></td></tr> | |||
</table> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
Synthetic cavitands and protein cavities have been widely studied as models for ligand recognition. Here we investigate the Met102 --> His substitution in the artificial L99A cavity in T4 lysozyme as a Kemp eliminase. The resulting enzyme had k(cat)/K(M) = 0.43 M(-1) s(-1) and a (k(cat)/K(M))/k(uncat) = 10(7) at pH 5.0. The crystal structure of this enzyme was determined at 1.30 A, as were the structures of four complexes of substrate and product analogs. The absence of ordered waters or hydrogen bonding interactions, and the presence of a common catalytic base (His102) in an otherwise hydrophobic, buried cavity, facilitated detailed analysis of the reaction mechanism and its optimization. Subsequent substitutions increased eliminase activity by an additional four-fold. As activity-enhancing substitutions were engineered into the cavity, protein stability decreased, consistent with the stability-function trade-off hypothesis. This and related model cavities may provide templates for studying protein design principles in radically simplified environments. | |||
Engineering a model protein cavity to catalyze the Kemp elimination.,Merski M, Shoichet BK Proc Natl Acad Sci U S A. 2012 Sep 17. PMID:22988064<ref>PMID:22988064</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
==See Also== | |||
*[[Lysozyme 3D structures|Lysozyme 3D structures]] | |||
== | == References == | ||
[[ | <references/> | ||
__TOC__ | |||
</StructureSection> | |||
[[Category: Enterobacteria phage t4]] | [[Category: Enterobacteria phage t4]] | ||
[[Category: Lysozyme]] | [[Category: Lysozyme]] | ||
[[Category: Merski, M | [[Category: Merski, M]] | ||
[[Category: Shoichet, B K | [[Category: Shoichet, B K]] | ||
[[Category: Alkylation with 2-mercaptoethanol]] | [[Category: Alkylation with 2-mercaptoethanol]] | ||
[[Category: Hydrolase]] | [[Category: Hydrolase]] | ||
Revision as of 17:28, 9 December 2014
T4 Lysozyme L99A/M102H with 2-Mercaptoethanol BoundT4 Lysozyme L99A/M102H with 2-Mercaptoethanol Bound
Structural highlights
Publication Abstract from PubMedSynthetic cavitands and protein cavities have been widely studied as models for ligand recognition. Here we investigate the Met102 --> His substitution in the artificial L99A cavity in T4 lysozyme as a Kemp eliminase. The resulting enzyme had k(cat)/K(M) = 0.43 M(-1) s(-1) and a (k(cat)/K(M))/k(uncat) = 10(7) at pH 5.0. The crystal structure of this enzyme was determined at 1.30 A, as were the structures of four complexes of substrate and product analogs. The absence of ordered waters or hydrogen bonding interactions, and the presence of a common catalytic base (His102) in an otherwise hydrophobic, buried cavity, facilitated detailed analysis of the reaction mechanism and its optimization. Subsequent substitutions increased eliminase activity by an additional four-fold. As activity-enhancing substitutions were engineered into the cavity, protein stability decreased, consistent with the stability-function trade-off hypothesis. This and related model cavities may provide templates for studying protein design principles in radically simplified environments. Engineering a model protein cavity to catalyze the Kemp elimination.,Merski M, Shoichet BK Proc Natl Acad Sci U S A. 2012 Sep 17. PMID:22988064[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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