View source for 1xkl


==Crystal Structure of Salicylic Acid-binding Protein 2 (SABP2) from Nicotiana tabacum, NESG Target AR2241==
<StructureSection load='1xkl' size='340' side='right'caption='[[1xkl]], [[Resolution|resolution]] 2.00&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1xkl]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Nicotiana_tabacum Nicotiana tabacum]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1XKL OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1XKL 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&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MSE:SELENOMETHIONINE'>MSE</scene>, <scene name='pdbligand=STH:2-AMINO-4H-1,3-BENZOXATHIIN-4-OL'>STH</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=1xkl FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1xkl OCA], [https://pdbe.org/1xkl PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1xkl RCSB], [https://www.ebi.ac.uk/pdbsum/1xkl PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1xkl ProSAT], [https://www.topsan.org/Proteins/NESGC/1xkl TOPSAN]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/SABP2_TOBAC SABP2_TOBAC] Required to convert methyl salicylate (MeSA) to salicylic acid (SA) as part of the signal transduction pathways that activate systemic acquired resistance in systemic tissue. MeSA is believed to be an inactive form that needs to be demethylated to exert a biological effect. Also able to catalyze the conversion of acibenzolar-S-methyl into acibenzolar to induce systemic acquired resistance.<ref>PMID:14673096</ref> <ref>PMID:15668381</ref> <ref>PMID:17916738</ref> <ref>PMID:19131332</ref> <ref>PMID:20621100</ref> <ref>PMID:20797615</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/xk/1xkl_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=1xkl ConSurf].
<div style="clear:both"></div>
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== Publication Abstract from PubMed ==
Salicylic acid (SA) is a critical signal for the activation of plant defense responses against pathogen infections. We recently identified SA-binding protein 2 (SABP2) from tobacco as a protein that displays high affinity for SA and plays a crucial role in the activation of systemic acquired resistance to plant pathogens. Here we report the crystal structures of SABP2, alone and in complex with SA at up to 2.1-A resolution. The structures confirm that SABP2 is a member of the alpha/beta hydrolase superfamily of enzymes, with Ser-81, His-238, and Asp-210 as the catalytic triad. SA is bound in the active site and is completely shielded from the solvent, consistent with the high affinity of this compound for SABP2. Our biochemical studies reveal that SABP2 has strong esterase activity with methyl salicylate as the substrate, and that SA is a potent product inhibitor of this catalysis. Modeling of SABP2 with MeSA in the active site is consistent with all these biochemical observations. Our results suggest that SABP2 may be required to convert MeSA to SA as part of the signal transduction pathways that activate systemic acquired resistance and perhaps local defense responses as well.

Structural and biochemical studies identify tobacco SABP2 as a methyl salicylate esterase and implicate it in plant innate immunity.,Forouhar F, Yang Y, Kumar D, Chen Y, Fridman E, Park SW, Chiang Y, Acton TB, Montelione GT, Pichersky E, Klessig DF, Tong L Proc Natl Acad Sci U S A. 2005 Feb 1;102(5):1773-8. Epub 2005 Jan 24. PMID:15668381<ref>PMID:15668381</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 1xkl" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Nicotiana tabacum]]
[[Category: Acton TB]]
[[Category: Chen Y]]
[[Category: Chiang Y]]
[[Category: Forouhar F]]
[[Category: Hunt JF]]
[[Category: Montelione GT]]
[[Category: Tong L]]