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4yin
From Proteopedia
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==Crystal structure of the extended-spectrum beta-lactamase OXA-145== | ==Crystal structure of the extended-spectrum beta-lactamase OXA-145== | ||
<StructureSection load='4yin' size='340' side='right' caption='[[4yin]], [[Resolution|resolution]] 2.30Å' scene=''> | <StructureSection load='4yin' size='340' side='right' caption='[[4yin]], [[Resolution|resolution]] 2.30Å' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
| - | <table><tr><td colspan='2'>[[4yin]] is a 2 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4YIN OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4YIN FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[4yin]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/"bacillus_aeruginosus"_(schroeter_1872)_trevisan_1885 "bacillus aeruginosus" (schroeter 1872) trevisan 1885]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4YIN OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4YIN FirstGlance]. <br> |
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=FLC:CITRATE+ANION'>FLC</scene></td></tr> | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=FLC:CITRATE+ANION'>FLC</scene></td></tr> | ||
| + | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">oxa145 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=287 "Bacillus aeruginosus" (Schroeter 1872) Trevisan 1885])</td></tr> | ||
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Beta-lactamase Beta-lactamase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.5.2.6 3.5.2.6] </span></td></tr> | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Beta-lactamase Beta-lactamase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.5.2.6 3.5.2.6] </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=4yin FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4yin OCA], [http://pdbe.org/4yin PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=4yin RCSB], [http://www.ebi.ac.uk/pdbsum/4yin PDBsum]</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=4yin FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4yin OCA], [http://pdbe.org/4yin PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=4yin RCSB], [http://www.ebi.ac.uk/pdbsum/4yin PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=4yin ProSAT]</span></td></tr> |
</table> | </table> | ||
| + | <div style="background-color:#fffaf0;"> | ||
| + | == Publication Abstract from PubMed == | ||
| + | OBJECTIVES: We previously described extended-spectrum oxacillinase OXA-145 from Pseudomonas aeruginosa, which differs from narrow-spectrum OXA-35 by loss of Leu-155. The deletion results in loss of benzylpenicillin hydrolysis and acquisition of activity against ceftazidime. We report the crystal structure of OXA-145 and provide the basis of its switch in substrate specificity. METHODS: OXA-145 variants were generated by site-directed mutagenesis and purified to homogeneity. The crystal structure of OXA-145 was determined and molecular dynamics simulations were performed. Kinetic parameters were investigated in the absence and in the presence of sodium hydrogen carbonate (NaHCO3) for representative substrates. RESULTS: The structure of OXA-145 was obtained at a resolution of 2.3 A and its superposition with that of OXA-10 showed that Trp-154 was shifted by 1.8 A away from the catalytic Lys-70, which was not N-carboxylated. Addition of NaHCO3 significantly increased the catalytic efficiency against penicillins, but not against ceftazidime. The active-site cavity of OXA-145 was larger than that of OXA-10, which may favour the accommodation of large molecules such as ceftazidime. Molecular dynamics simulations of OXA-145 in complex with ceftazidime revealed two highly coordinated water molecules on the alpha- or beta-face of the acyl ester bond, between Ser-67 and ceftazidime, which could be involved in the catalytic process. CONCLUSIONS: Deletion of Leu-155 resulted in inefficient positioning of Trp-154, leading to a non-carboxylated Lys-70 and thus to loss of hydrolysis of the penicillins. Ceftazidime hydrolysis could be attributed to enlargement of the active site and to a catalytic mechanism independent of the carboxylated Lys-70. | ||
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| + | Structural insights into the loss of penicillinase and the gain of ceftazidimase activities by OXA-145 beta-lactamase in Pseudomonas aeruginosa.,Meziane-Cherif D, Bonnet R, Haouz A, Courvalin P J Antimicrob Chemother. 2016 Feb;71(2):395-402. doi: 10.1093/jac/dkv375. Epub, 2015 Nov 14. PMID:26568564<ref>PMID:26568564</ref> | ||
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| + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
| + | </div> | ||
| + | <div class="pdbe-citations 4yin" style="background-color:#fffaf0;"></div> | ||
| + | |||
| + | ==See Also== | ||
| + | *[[Beta-lactamase|Beta-lactamase]] | ||
| + | == References == | ||
| + | <references/> | ||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> | ||
Revision as of 06:15, 18 April 2018
Crystal structure of the extended-spectrum beta-lactamase OXA-145
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