View source for 1er8


==THE ACTIVE SITE OF ASPARTIC PROTEINASES==
<StructureSection load='1er8' size='340' side='right'caption='[[1er8]], [[Resolution|resolution]] 2.00&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1er8]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Cryphonectria_parasitica Cryphonectria parasitica] and [https://en.wikipedia.org/wiki/Equus_caballus Equus caballus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1ER8 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1ER8 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=DHI:D-HISTIDINE'>DHI</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=1er8 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1er8 OCA], [https://pdbe.org/1er8 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1er8 RCSB], [https://www.ebi.ac.uk/pdbsum/1er8 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1er8 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/CARP_CRYPA CARP_CRYPA] 
== 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/er/1er8_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=1er8 ConSurf].
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== Publication Abstract from PubMed ==
The active site of the aspartic proteinase, endothiapepsin, has been defined by X-ray analysis and restrained least-squares refinement at 2.1 A resolution with a crystallographic agreement value of 0.16. The environments of the two catalytically important aspartyl groups are remarkably similar and the contributions of the NH2- and COOH-terminal domains to the catalytic centre are related by a local 2-fold axis. The carboxylates of the aspartyls share a hydrogen bond and have equivalent contacts to a bound water molecule or hydroxonium ion lying on the local diad. The main chains around 32 and 215 are connected by a novel interaction involving diad-related threonines. It is suggested that the two pKa values of the active site aspartyls arise from a structure not unlike that in maleic acid with a hydrogen-bonded intermediate species and a dicarboxylate characterised by electrostatic repulsions between the two negatively charged groups.

The active site of aspartic proteinases.,Pearl L, Blundell T FEBS Lett. 1984 Aug 20;174(1):96-101. PMID:6381096<ref>PMID:6381096</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 1er8" style="background-color:#fffaf0;"></div>

==See Also==
*[[Pepsin|Pepsin]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Cryphonectria parasitica]]
[[Category: Equus caballus]]
[[Category: Large Structures]]
[[Category: Blundell TL]]
[[Category: Cooper JB]]
[[Category: Hemmings AM]]
[[Category: Szelke M]]
[[Category: Veerapandian B]]