View source for 1q5t


==Gln48 PLA2 separated from Vipoxin from the venom of Vipera ammodytes meridionalis.==
<StructureSection load='1q5t' size='340' side='right'caption='[[1q5t]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1q5t]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Vipera_ammodytes_meridionalis Vipera ammodytes meridionalis]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1Q5T OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1Q5T 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]] 1.9&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=SO4:SULFATE+ION'>SO4</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=1q5t FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1q5t OCA], [https://pdbe.org/1q5t PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1q5t RCSB], [https://www.ebi.ac.uk/pdbsum/1q5t PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1q5t ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/PA2HA_VIPAE PA2HA_VIPAE] Heterodimer: postsynaptic neurotoxin.<ref>PMID:23554559</ref>   Monomer: Acidic phospholipase A2 homolog that is non-toxic.<ref>PMID:23554559</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/q5/1q5t_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=1q5t ConSurf].
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== Publication Abstract from PubMed ==
Phospholipase A2 is an "interfacial" enzyme and its binding to negatively charged surfaces is an important step during catalysis. The Gln48 phospholipase A2 from the venom of Vipera ammodytes meridionalis plays the role of chaperone and directs a toxic His48 PLA2 onto its acceptor. In the venom the two phospholipases A2 exist as a postsynaptic neurotoxic complex, Vipoxin. The X-ray structure of Gln48 PLA2, complexed to sulphate ions, which mimic the negatively charged groups of anionic membranes, has been determined by the molecular replacement method and refined to 1.9A resolution. The protein forms a homodimer stabilized by ionic, hydrophobic, and hydrogen-bond interactions. The structure reveals two anion-binding sites per subunit. These sites are probably involved in interactions with the negatively charged membrane surface and, in this way, in the "targeting" of the toxic component to the receptors of the postsynaptic membranes. In the absence of the chaperone subunit the toxin changes the target of the physiological attack. A comparison of the homodimeric Gln48 PLA2 structure with that of the heterodimeric Vipoxin reveals differences in regions involved in the pharmacological activity of the toxin. This fact, except the active site histidine substitution, can explain the absence of toxicity in the Gln48 protein in comparison to the His48 phospholipase A2.

The X-ray structure of a snake venom Gln48 phospholipase A2 at 1.9A resolution reveals anion-binding sites.,Georgieva DN, Perbandt M, Rypniewski W, Hristov K, Genov N, Betzel C Biochem Biophys Res Commun. 2004 Mar 26;316(1):33-8. PMID:15003507<ref>PMID:15003507</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 1q5t" style="background-color:#fffaf0;"></div>

==See Also==
*[[Phospholipase A2 3D structures|Phospholipase A2 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Vipera ammodytes meridionalis]]
[[Category: Betzel C]]
[[Category: Genov N]]
[[Category: Georgieva DN]]
[[Category: Hristov K]]
[[Category: Perbandt M]]
[[Category: Rypniewski W]]