4hst: Difference between revisions
From Proteopedia
Jump to navigationJump to search
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
==Crystal structure of a double mutant of a class III engineered cephalosporin acylase== | |||
<StructureSection load='4hst' size='340' side='right' caption='[[4hst]], [[Resolution|resolution]] 1.57Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[4hst]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Pseudomonas Pseudomonas]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4HST OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4HST FirstGlance]. <br> | |||
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=GLJ:5,5-DIHYDROXY-L-NORVALINE'>GLJ</scene></td></tr> | |||
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[4hsr|4hsr]]</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=4hst FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4hst OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4hst RCSB], [http://www.ebi.ac.uk/pdbsum/4hst PDBsum]</span></td></tr> | |||
</table> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
The crystal structure of wild-type form of glutaryl-7-ACA acylase from Pseudomonas N176 and a double mutant of the protein (His57betaSer/His70betaSer) that displays enhanced catalytic efficiency on cephalosporin C over glutaryl-7-aminocephalosporanic acid has been determined. The structures show a heterodimer made up of an alpha chain (229 residues) and a beta chain (543 residues) with a deep cavity, which constitutes the active site. Comparison of the wild-type and mutant structures provide insights into the molecular reasons for the observed enhanced specificity on cephalosporin C over glutaryl-7-aminocephalosporanic acid and offered the basis to evolve a further improve enzyme variant. The nucleophilic catalytic serine residue, Ser1beta, is situated at the base of the active site cavity. The electron density reveals a ligand covalently bound to the catalytic serine residue such that a tetrahedral adduct is formed. This is proposed to mimic the transition state of the enzyme for both the maturation step and the catalysis of the substrates. A view of the transitions state configuration of the enzyme provides important insights into the mechanism of substrate binding and catalysis. | |||
Structure of a class III engineered cephalosporin acylase. Comparisons to class I acylase and implications for differences in substrate specificity and catalytic activity.,Golden E, Paterson R, Tie WJ, Anandan A, Flematti G, Molla G, Rosini E, Pollegioni L, Vrielink A Biochem J. 2013 Feb 4. PMID:23373797<ref>PMID:23373797</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
</div> | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Pseudomonas]] | [[Category: Pseudomonas]] | ||
[[Category: Anandan, A | [[Category: Anandan, A]] | ||
[[Category: Flematti, G | [[Category: Flematti, G]] | ||
[[Category: Golden, E | [[Category: Golden, E]] | ||
[[Category: Molla, G | [[Category: Molla, G]] | ||
[[Category: Patterson, R | [[Category: Patterson, R]] | ||
[[Category: Pollegioni, L | [[Category: Pollegioni, L]] | ||
[[Category: Rosini, E | [[Category: Rosini, E]] | ||
[[Category: Tie, W J | [[Category: Tie, W J]] | ||
[[Category: Vrielink, A | [[Category: Vrielink, A]] | ||
[[Category: Hydrolase]] | [[Category: Hydrolase]] | ||
[[Category: N-terminal hydrolase]] | [[Category: N-terminal hydrolase]] | ||
