View source for 3kos


==Structure of the AmpR effector binding domain from Citrobacter freundii==
<StructureSection load='3kos' size='340' side='right'caption='[[3kos]], [[Resolution|resolution]] 1.83&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3kos]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Citrobacter_freundii Citrobacter freundii]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3KOS OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3KOS 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]] 1.83&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=MES:2-(N-MORPHOLINO)-ETHANESULFONIC+ACID'>MES</scene>, <scene name='pdbligand=MSE:SELENOMETHIONINE'>MSE</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=3kos FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3kos OCA], [https://pdbe.org/3kos PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3kos RCSB], [https://www.ebi.ac.uk/pdbsum/3kos PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3kos ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/AMPR_CITFR AMPR_CITFR] Regulates the expression of the beta-lactamase gene. Represses cephalosporinase (AmpC) in the presence of beta-lactams and induces it in the absence of them.
== 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/ko/3kos_consurf.spt"</scriptWhenChecked>
    <scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview03.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=3kos ConSurf].
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== Publication Abstract from PubMed ==
Hyperproduction of AmpC beta-lactamase (AmpC) is a formidable mechanism of resistance to penicillins and cephalosporins in Gram-negative bacteria such as Pseudomonas aeruginosa and Enterobacteriaceae. AmpC expression is regulated by the LysR-type transcriptional regulator AmpR. ampR and ampC genes form a divergent operon with overlapping promoters to which AmpR binds and regulates the transcription of both genes. AmpR induces ampC by binding to one member of the family of 1,6-anhydro-N-acetylmuramyl peptides, which are cytosolic catabolites of peptidoglycan that accumulate during beta-lactam challenge. To gain structural insights into AmpR regulation, we determined the crystal structure of the effector binding domain (EBD) of AmpR from Citrobacter freundii up to 1.83 A resolution. The AmpR EBD is dimeric and each monomer comprises two subdomains that adopt alpha/beta Rossmann-like folds. Located between the monomer subdomains is a pocket that was found to bind the crystallization buffer molecule 2-(N-morpholino)ethanesulfonic acid. The pocket, together with a groove along the surface of subdomain I, forms a putative effector binding site into which a molecule of 1,6-anhydro-N-acetylmuramyl pentapeptide could be modeled. Amino acid substitutions at the base of the interdomain pocket either were found to render AmpR incapable of inducing ampC (Thr103Val, Ser221Ala and Tyr264Phe) or resulted in constitutive ampC expression (Gly102Glu). While the substitutions that prevented ampC induction did not alter the overall AmpR EBD structure, circular dichroism spectroscopy revealed that the nonconservative Gly102Glu mutation affected EBD secondary structure, confirming previous work suggesting that Gly102Glu induces a conformational change to result in constitutive AmpC production.

Crystal structure of the AmpR effector binding domain provides insight into the molecular regulation of inducible ampc beta-lactamase.,Balcewich MD, Reeve TM, Orlikow EA, Donald LJ, Vocadlo DJ, Mark BL J Mol Biol. 2010 Jul 30;400(5):998-1010. Epub 2010 May 31. PMID:20594961<ref>PMID:20594961</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 3kos" style="background-color:#fffaf0;"></div>

==See Also==
*[[Transcriptional activator 3D structures|Transcriptional activator 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Citrobacter freundii]]
[[Category: Large Structures]]
[[Category: Balcewich MD]]
[[Category: Mark BL]]