View source for 1k55


==OXA 10 class D beta-lactamase at pH 7.5==
<StructureSection load='1k55' size='340' side='right'caption='[[1k55]], [[Resolution|resolution]] 1.39&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1k55]] is a 4 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=1K55 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1K55 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]] 1.39&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=EDO:1,2-ETHANEDIOL'>EDO</scene>, <scene name='pdbligand=KCX:LYSINE+NZ-CARBOXYLIC+ACID'>KCX</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</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=1k55 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1k55 OCA], [https://pdbe.org/1k55 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1k55 RCSB], [https://www.ebi.ac.uk/pdbsum/1k55 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1k55 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/BLO10_PSEAI BLO10_PSEAI] Hydrolyzes both carbenicillin and oxacillin.
== Evolutionary Conservation ==
[[Image:Consurf_key_small.gif|200px|right]]
Check<jmol>
  <jmolCheckbox>
    <scriptWhenChecked>; select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/k5/1k55_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked>
    <text>to colour the structure by Evolutionary Conservation</text>
  </jmolCheckbox>
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/main_output.php?pdb_ID=1k55 ConSurf].
<div style="clear:both"></div>
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== Publication Abstract from PubMed ==
beta-Lactamases are the resistance enzymes for beta-lactam antibiotics, of which four classes are known. beta-lactamases hydrolyze the beta-lactam moieties of these antibiotics, rendering them inactive. It is shown herein that the class D OXA-10 beta-lactamase depends critically on an unusual carbamylated lysine as the basic residue for both the enzyme acylation and deacylation steps of catalysis. The formation of carbamylated lysine is reversible. Evidence is presented that this enzyme is dimeric and carbamylated in living bacteria. High-resolution x-ray structures for the native enzyme were determined at pH values of 6.0, 6.5, 7.5, and 8.5. Two dimers are present per asymmetric unit. One monomer in each dimer was carbamylated at pH 6.0, whereas all four monomers were fully carbamylated at pH 8.5. At the intermediate pH values, one monomer of each dimer was carbamylated, and the other showed a mixture of carbamylated and non-carbamylated lysines. It would appear that, as the pH increased for the sample, additional lysines were "titrated" by carbamylation. A handful of carbamylated lysines are known from protein crystallographic data, all of which have been attributed roles in structural stabilization (mostly as metal ligands) of the proteins. This paper reports a previously unrecognized role for a noncoordinated carbamylate lysine as a basic residue involved in mechanistic reactions of an enzyme, which indicates another means for expansion of the catalytic capabilities of the amino acids in nature beyond the 20 common amino acids in development of biological catalysts.

Critical involvement of a carbamylated lysine in catalytic function of class D beta-lactamases.,Golemi D, Maveyraud L, Vakulenko S, Samama JP, Mobashery S Proc Natl Acad Sci U S A. 2001 Dec 4;98(25):14280-5. Epub 2001 Nov 27. PMID:11724923<ref>PMID:11724923</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 1k55" style="background-color:#fffaf0;"></div>

==See Also==
*[[Beta-lactamase 3D structures|Beta-lactamase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Pseudomonas aeruginosa]]
[[Category: Golemi D]]
[[Category: Maveyraud L]]
[[Category: Mobashery S]]
[[Category: Samama JP]]
[[Category: Vakulenko S]]