View source for 3ima


==Complex structure of tarocystatin and papain==
<StructureSection load='3ima' size='340' side='right'caption='[[3ima]], [[Resolution|resolution]] 2.03&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3ima]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Carica_papaya Carica papaya] and [https://en.wikipedia.org/wiki/Colocasia_esculenta Colocasia esculenta]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3IMA OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3IMA 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]] 2.03&#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=OCS:CYSTEINESULFONIC+ACID'>OCS</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=3ima FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3ima OCA], [https://pdbe.org/3ima PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3ima RCSB], [https://www.ebi.ac.uk/pdbsum/3ima PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3ima ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/PAPA1_CARPA PAPA1_CARPA] 
== 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/im/3ima_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=3ima ConSurf].
<div style="clear:both"></div>
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== Publication Abstract from PubMed ==
Tarocystatin (CeCPI) from taro (Colocasia esculenta cv. Kaohsiung no. 1), a group-2 phytocystatin, shares a conserved N-terminal cystatin domain (NtD) with other phytocystatins but contains a C-terminal cystatin-like extension (CtE). The structure of the tarocystatin-papain complex and the domain interaction between NtD and CtE in tarocystatin have not been determined. We resolved the crystal structure of the phytocystatin-papain complex at resolution 2.03 A. Surprisingly, the structure of the NtD-papain complex in a stoichiometry of 1:1 could be built, with no CtE observed. Only two remnant residues of CtE could be built in the structure of the CtE-papain complex. Therefore, CtE is easily digested by papain. To further characterize the interaction between NtD and CtE, three segments of tarocystatin, including the full-length (FL), NtD and CtE, were used to analyze the domain-domain interaction and the inhibition ability. The results from glutaraldehyde cross-linking and yeast two-hybrid assay indicated the existence of an intrinsic flexibility in the region linking NtD and CtE for most tarocystatin molecules. In the inhibition activity assay, the glutathione-S-transferase (GST)-fused FL showed the highest inhibition ability without residual peptidase activity, and GST-NtD and FL showed almost the same inhibition ability, which was higher than with NtD alone. On the basis of the structures, the linker flexibility and inhibition activity of tarocystatins, we propose that the overhangs from the cystatin domain may enhance the inhibition ability of the cystatin domain against papain.

Crystal structure of tarocystatin-papain complex: implications for the inhibition property of group-2 phytocystatins.,Chu MH, Liu KL, Wu HY, Yeh KW, Cheng YS Planta. 2011 Aug;234(2):243-54. Epub 2011 Mar 18. PMID:21416241<ref>PMID:21416241</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 3ima" style="background-color:#fffaf0;"></div>

==See Also==
*[[Papain|Papain]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Carica papaya]]
[[Category: Colocasia esculenta]]
[[Category: Large Structures]]
[[Category: Cheng YS]]
[[Category: Chu MH]]
[[Category: Liu KL]]
[[Category: Yeh KW]]