View source for 1tug


==Aspartate Transcarbamoylase Catalytic Chain Mutant E50A Complex with Phosphonoacetamide, Malonate, and Cytidine-5-Prime-Triphosphate (CTP)==
<StructureSection load='1tug' size='340' side='right'caption='[[1tug]], [[Resolution|resolution]] 2.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1tug]] is a 4 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=1TUG OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1TUG 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]] 2.1&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CTP:CYTIDINE-5-TRIPHOSPHATE'>CTP</scene>, <scene name='pdbligand=MLI:MALONATE+ION'>MLI</scene>, <scene name='pdbligand=PCT:PHOSPHONOACETAMIDE'>PCT</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</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=1tug FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1tug OCA], [https://pdbe.org/1tug PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1tug RCSB], [https://www.ebi.ac.uk/pdbsum/1tug PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1tug ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/PYRB_ECOLI PYRB_ECOLI] 
== 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/tu/1tug_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=1tug ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
A detailed description of the transition that allosteric enzymes undergo constitutes a major challenge in structural biology. We have succeeded in trapping four distinct allosteric states of a mutant enzyme of Escherichia coli aspartate transcarbomylase and determining their structures by X-ray crystallography. The mutant version of aspartate transcarbamoylase in which Glu50 in the catalytic chains was replaced by Ala destabilizes the native R state and shifts the equilibrium towards the T state. This behavior allowed the use of substrate analogs such as phosphonoacetamide and malonate to trap the enzyme in T-like and R-like structures that are distinct from the T-state structure of the wild-type enzyme (as represented by the structure of the enzyme with CTP bound and the R-state structure as represented by the structure with N-(phosphonacetyl)-L-aspartate bound). These structures shed light on the nature and the order of internal structural rearrangements during the transition from the T to the R state. They also suggest an explanation for diminished activity of the E50A enzyme and for the change in reaction mechanism from ordered to random for this mutant enzyme.

Monitoring the transition from the T to the R state in E.coli aspartate transcarbamoylase by X-ray crystallography: crystal structures of the E50A mutant enzyme in four distinct allosteric states.,Stieglitz K, Stec B, Baker DP, Kantrowitz ER J Mol Biol. 2004 Aug 13;341(3):853-68. PMID:15288791<ref>PMID:15288791</ref>

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

==See Also==
*[[Aspartate carbamoyltransferase 3D structures|Aspartate carbamoyltransferase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli]]
[[Category: Large Structures]]
[[Category: Baker DP]]
[[Category: Kantrowitz ER]]
[[Category: Stec B]]
[[Category: Stieglitz K]]