View source for 2qw1


==Glucose/galactose binding protein bound to 3-O-methyl D-glucose==
<StructureSection load='2qw1' size='340' side='right'caption='[[2qw1]], [[Resolution|resolution]] 1.70&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2qw1]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2QW1 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2QW1 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]] 1.7&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=3MG:3-O-METHYL-BETA-D-GLUCOPYRANOSE'>3MG</scene>, <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=NA:SODIUM+ION'>NA</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=2qw1 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2qw1 OCA], [https://pdbe.org/2qw1 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2qw1 RCSB], [https://www.ebi.ac.uk/pdbsum/2qw1 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2qw1 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/MGLB_ECOLI MGLB_ECOLI] Part of the ABC transporter complex MglABC involved in galactose/methyl galactoside import (Probable). In addition, binds D-galactose and D-glucose and plays a role in the chemotaxis towards these two sugars by interacting with the Trg chemoreceptor (PubMed:3057628, PubMed:4927373). Chemotaxis requires MglB, but not MglA or MglC (PubMed:6294056).<ref>PMID:3057628</ref> <ref>PMID:4927373</ref> <ref>PMID:6294056</ref> <ref>PMID:1719366</ref> <ref>PMID:6294056</ref> 
== 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/qw/2qw1_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=2qw1 ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Many receptors undergo ligand-induced conformational changes to initiate signal transduction. Periplasmic binding proteins (PBPs) are bacterial receptors that exhibit dramatic conformational changes upon ligand binding. These proteins mediate a wide variety of fundamental processes including transport, chemotaxis, and quorum sensing. Despite the importance of these receptors, no PBP antagonists have been identified and characterized. In this study, we identify 3-O-methyl-d-glucose as an antagonist of glucose/galactose-binding protein and demonstrate that it inhibits glucose chemotaxis in E. coli. Using small-angle X-ray scattering and X-ray crystallography, we show that this antagonist acts as a wedge. It prevents the large-scale domain closure that gives rise to the active signaling state. Guided by these results and the structures of open and closed glucose/galactose-binding protein, we designed and synthesized an antagonist composed of two linked glucose residues. These findings provide a blueprint for the design of new bacterial PBP inhibitors. Given the key role of PBPs in microbial physiology, we anticipate that PBP antagonists will have widespread uses as probes and antimicrobial agents.

Structure-based design of a periplasmic binding protein antagonist that prevents domain closure.,Borrok MJ, Zhu Y, Forest KT, Kiessling LL ACS Chem Biol. 2009 Jun 19;4(6):447-56. PMID:19348466<ref>PMID:19348466</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 2qw1" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli]]
[[Category: Large Structures]]
[[Category: Borrok MJ]]
[[Category: Forest KT]]
[[Category: Kiessling LL]]