View source for 9ixr


==Crystal structure of OXA-10 variant A124T in the complex with ceftazidime==
<StructureSection load='9ixr' size='340' side='right'caption='[[9ixr]], [[Resolution|resolution]] 2.19&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[9ixr]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Pseudomonas_aeruginosa Pseudomonas aeruginosa]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=9IXR OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=9IXR 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]] 2.19&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CTJ:1-({(2R)-2-[(1R)-1-{[(2Z)-2-(2-AMINO-1,3-THIAZOL-4-YL)-2-{[(2-CARBOXYPROPAN-2-YL)OXY]IMINO}ACETYL]AMINO}-2-OXOETHYL]-4-CARBOXY-3,6-DIHYDRO-2H-1,3-THIAZIN-5-YL}METHYL)PYRIDINIUM'>CTJ</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=9ixr FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=9ixr OCA], [https://pdbe.org/9ixr PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=9ixr RCSB], [https://www.ebi.ac.uk/pdbsum/9ixr PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=9ixr ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/BLO10_PSEAI BLO10_PSEAI] Hydrolyzes both carbenicillin and oxacillin.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The extensive use of beta-lactam antibiotics has led to significant resistance, primarily due to hydrolysis by beta-lactamases. OXA class D beta-lactamases can hydrolyze a wide range of beta-lactam antibiotics, rendering many treatments ineffective. We investigated the effects of single amino acid substitutions in OXA-10 on its substrate spectrum. Broad-spectrum variants with point mutations were searched and biochemically verified. Three key residues, G157D, A124T, and N73S, were confirmed in the variants, and their crystal structures were determined. Based on an enzyme kinetics study, the hydrolytic activity against broad-spectrum cephalosporins, particularly ceftazidime, was significantly enhanced by the G157D mutation in loop 2. The A124T or N73S mutation close to loop 2 also resulted in higher ceftazidime activity. All structures of variants with point mutations in loop 2 or nearby exhibited increased loop 2 flexibility, which facilitated the binding of ceftazidime. These results highlight the effect of a single amino acid substitution in OXA-10 on broad-spectrum drug resistance. Structure-activity relationship studies will help us understand the drug resistance spectrum of beta-lactamases, enhance the effectiveness of existing beta-lactam antibiotics, and develop new drugs.

Structural insights into alterations in the substrate spectrum of serine-beta-lactamase OXA-10 from Pseudomonas aeruginosa by single amino acid substitutions.,Lee CE, Park Y, Park H, Kwak K, Lee H, Yun J, Lee D, Lee JH, Lee SH, Kang LW Emerg Microbes Infect. 2024 Dec;13(1):2412631. doi: , 10.1080/22221751.2024.2412631. Epub 2024 Oct 22. PMID:39361442<ref>PMID:39361442</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 9ixr" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Pseudomonas aeruginosa]]
[[Category: Kang LW]]
[[Category: Lee CE]]
[[Category: Park HJ]]
[[Category: Park YS]]