View source for 1iwe


==IMP Complex of the Recombinant Mouse-Muscle Adenylosuccinate Synthetase==
<StructureSection load='1iwe' size='340' side='right'caption='[[1iwe]], [[Resolution|resolution]] 2.10&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1iwe]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Mus_musculus Mus musculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1IWE OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1IWE 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=ACT:ACETATE+ION'>ACT</scene>, <scene name='pdbligand=IMP:INOSINIC+ACID'>IMP</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</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=1iwe FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1iwe OCA], [https://pdbe.org/1iwe PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1iwe RCSB], [https://www.ebi.ac.uk/pdbsum/1iwe PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1iwe ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/PURA1_MOUSE PURA1_MOUSE] Component of the purine nucleotide cycle (PNC), which interconverts IMP and AMP to regulate the nucleotide levels in various tissues, and which contributes to glycolysis and ammoniagenesis. Catalyzes the first committed step in the biosynthesis of AMP from IMP.<ref>PMID:12482871</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/iw/1iwe_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=1iwe ConSurf].
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== Publication Abstract from PubMed ==
Prokaryotes have a single form of adenylosuccinate synthetase that controls the committed step of AMP biosynthesis, but vertebrates have two isozymes of the synthetase. The basic isozyme, which predominates in muscle, participates in the purine nucleotide cycle, has an active site conformation different from that of the Escherichia coli enzyme, and exhibits significant differences in ligand recognition. Crystalline complexes presented here of the recombinant basic isozyme from mouse show the following. GTP alone binds to the active site without inducing a conformational change. IMP in combination with an acetate anion induces major conformational changes and organizes the active site for catalysis. IMP, in the absence of GTP, binds to the GTP pocket of the synthetase. The combination of GTP and IMP results in the formation of a stable complex of 6-phosphoryl-IMP and GDP in the presence or absence of hadacidin. The response of the basic isozyme to GTP alone differs from that of synthetases from plants, and yet the conformation of the mouse basic and E. coli synthetases in their complexes with GDP, 6-phosphoryl-IMP, and hadacidin are nearly identical. Hence, reported differences in ligand recognition among synthetases probably arise from conformational variations observed in partially ligated enzymes.

IMP, GTP, and 6-phosphoryl-IMP complexes of recombinant mouse muscle adenylosuccinate synthetase.,Iancu CV, Borza T, Fromm HJ, Honzatko RB J Biol Chem. 2002 Jul 26;277(30):26779-87. Epub 2002 May 9. PMID:12004071<ref>PMID:12004071</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 1iwe" style="background-color:#fffaf0;"></div>

==See Also==
*[[Adenylosuccinate synthetase 3D structures|Adenylosuccinate synthetase 3D structures]]
== References ==
<references/>
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</StructureSection>
[[Category: Large Structures]]
[[Category: Mus musculus]]
[[Category: Borza T]]
[[Category: Fromm HJ]]
[[Category: Honzatko RB]]
[[Category: Iancu CV]]