View source for 3oph


==ESBL R164S mutant of SHV-1 beta-lactamase==
<StructureSection load='3oph' size='340' side='right'caption='[[3oph]], [[Resolution|resolution]] 1.34&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3oph]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Klebsiella_pneumoniae Klebsiella pneumoniae]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3OPH OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3OPH 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]] 1.34&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=EPE:4-(2-HYDROXYETHYL)-1-PIPERAZINE+ETHANESULFONIC+ACID'>EPE</scene>, <scene name='pdbligand=MA4:CYCLOHEXYL-HEXYL-BETA-D-MALTOSIDE'>MA4</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=3oph FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3oph OCA], [https://pdbe.org/3oph PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3oph RCSB], [https://www.ebi.ac.uk/pdbsum/3oph PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3oph ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/BLA1_KLEPN BLA1_KLEPN] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Among Gram-negative bacteria, resistance to beta-lactams is mediated primarily by beta-lactamases (EC 3.2.6.5), periplasmic enzymes that inactivate beta-lactam antibiotics. Substitutions at critical amino acid positions in the class A beta-lactamase families result in enzymes that can hydrolyze extended-spectrum cephalosporins, thus demonstrating an "extended-spectrum" beta-lactamase (ESBL) phenotype. Using SHV ESBLs with substitutions in the Omega loop (R164H and R164S) as target enzymes to understand this enhanced biochemical capability and to serve as a basis for novel beta-lactamase inhibitor development, we determined the spectra of activity and crystal structures of these variants. We also studied the inactivation of the R164H and R164S mutants with tazobactam and SA2-13, a unique beta-lactamase inhibitor that undergoes a distinctive reaction chemistry in the active site. We noted that the reduced Ki values for the R164H and R164S mutants with SA2-13 are comparable to those with tazobactam (submicromolar). The apo enzyme crystal structures of the R164H and R164S SHV variants revealed an ordered Omega loop architecture that became disordered when SA2-13 was bound. Important structural alterations that result from the binding of SA2-13 explain the enhanced susceptibility of these ESBL enzymes to this inhibitor and highlight ligand-dependent Omega loop flexibility as a mechanism for accommodating and hydrolyzing beta-lactam substrates.

Ligand-dependent disorder of the Omega loop observed in extended-spectrum SHV-type beta-lactamase.,Sampson JM, Ke W, Bethel CR, Pagadala SR, Nottingham MD, Bonomo RA, Buynak JD, van den Akker F Antimicrob Agents Chemother. 2011 May;55(5):2303-9. Epub 2011 Feb 28. PMID:21357298<ref>PMID:21357298</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 3oph" style="background-color:#fffaf0;"></div>

==See Also==
*[[Beta-lactamase 3D structures|Beta-lactamase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Klebsiella pneumoniae]]
[[Category: Large Structures]]
[[Category: Sampson JM]]
[[Category: Van den Akker F]]