View source for 2g9q


==The crystal structure of the glycogen phosphorylase b- 1AB complex==
<StructureSection load='2g9q' size='340' side='right'caption='[[2g9q]], [[Resolution|resolution]] 2.50&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2g9q]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Oryctolagus_cuniculus Oryctolagus cuniculus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2G9Q OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2G9Q 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]] 2.5&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=1AB:1,4-DIDEOXY-1,4-IMINO-D-ARABINITOL'>1AB</scene>, <scene name='pdbligand=LLP:(2S)-2-AMINO-6-[[3-HYDROXY-2-METHYL-5-(PHOSPHONOOXYMETHYL)PYRIDIN-4-YL]METHYLIDENEAMINO]HEXANOIC+ACID'>LLP</scene>, <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</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=2g9q FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2g9q OCA], [https://pdbe.org/2g9q PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2g9q RCSB], [https://www.ebi.ac.uk/pdbsum/2g9q PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2g9q ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/PYGM_RABIT PYGM_RABIT] Phosphorylase is an important allosteric enzyme in carbohydrate metabolism. Enzymes from different sources differ in their regulatory mechanisms and in their natural substrates. However, all known phosphorylases share catalytic and structural properties.
== 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/g9/2g9q_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=2g9q ConSurf].
<div style="clear:both"></div>
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== Publication Abstract from PubMed ==
Iminosugars DAB (5), isofagomine (9), and several N-substituted derivatives have been identified as potent inhibitors of liver glycogen phosphorylase a (IC(50) = 0.4-1.2 microM) and of basal and glucagon-stimulated glycogenolysis (IC(50) = 1-3 microM). The X-ray structures of 5, 9, and its N-3-phenylpropyl analogue 8 in complex with rabbit muscle glycogen phosphorylase (GPb) shows that iminosugars bind tightly at the catalytic site in the presence of the substrate phosphate and induce conformational changes that characterize the R-state conformation of the enzyme. Charged nitrogen N1 is within hydrogen-bonding distance with the carbonyl oxygen of His377 (5) and in ionic contact with the substrate phosphate oxygen (8 and 9). Our findings suggest that the inhibitors function as oxocarbenium ion transition-state analogues. The conformational change to the R state provides an explanation for previous findings that 5, unlike inhibitors that favor the T state, promotes phosphorylation of GPb in hepatocytes with sequential inactivation of glycogen synthase.

Iminosugars as potential inhibitors of glycogenolysis: structural insights into the molecular basis of glycogen phosphorylase inhibition.,Oikonomakos NG, Tiraidis C, Leonidas DD, Zographos SE, Kristiansen M, Jessen CU, Norskov-Lauritsen L, Agius L J Med Chem. 2006 Sep 21;49(19):5687-701. PMID:16970395<ref>PMID:16970395</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 2g9q" style="background-color:#fffaf0;"></div>

==See Also==
*[[Glycogen phosphorylase 3D structures|Glycogen phosphorylase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Oryctolagus cuniculus]]
[[Category: Agius L]]
[[Category: Kristiansen M]]
[[Category: Leonidas DD]]
[[Category: Oikonomakos NG]]
[[Category: Tiraidis C]]
[[Category: Zographos SE]]