View source for 2bd9


==Porcine pancreatic elastase complexed with beta-casomorphin-7 and Arg-Phe at pH 5.0 (50 min soak) and immersed in pH 9 buffer for 28 seconds (2nd pH jump)==
<StructureSection load='2bd9' size='340' side='right'caption='[[2bd9]], [[Resolution|resolution]] 1.90&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2bd9]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Pig Pig]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2BD9 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2BD9 FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene></td></tr>
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1hax|1hax]], [[1hay|1hay]], [[1haz|1haz]], [[1qix|1qix]], [[2bb4|2bb4]], [[2bd2|2bd2]], [[2bd3|2bd3]], [[2bd4|2bd4]], [[2bd5|2bd5]], [[2bd6|2bd6]], [[2bd7|2bd7]], [[2bd8|2bd8]], [[2bda|2bda]], [[2bdb|2bdb]], [[2bdc|2bdc]]</td></tr>
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Pancreatic_elastase Pancreatic elastase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.21.36 3.4.21.36] </span></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2bd9 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2bd9 OCA], [http://pdbe.org/2bd9 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=2bd9 RCSB], [http://www.ebi.ac.uk/pdbsum/2bd9 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=2bd9 ProSAT]</span></td></tr>
</table>
== Function ==
[[http://www.uniprot.org/uniprot/CELA1_PIG CELA1_PIG]] Acts upon elastin. 
== 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/bd/2bd9_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=2bd9 ConSurf].
<div style="clear:both"></div>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Although the subject of many studies, detailed structural information on aspects of the catalytic cycle of serine proteases is lacking. Crystallographic analyses were performed in which an acyl-enzyme complex, formed from elastase and a peptide, was reacted with a series of nucleophilic dipeptides. Multiple analyses led to electron density maps consistent with the formation of a tetrahedral species. In certain cases, apparent peptide bond formation at the active site was observed, and the electron density maps suggested production of a cis-amide rather than a trans-amide. Evidence for a cis-amide configuration was also observed in the noncovalent complex between elastase and an alpha1-antitrypsin-derived tetrapeptide. Although there are caveats on the relevance of the crystallographic data to solution catalysis, the results enable detailed proposals for the pathway of the acylation step to be made. At least in some cases, it is proposed that the alcohol of Ser-195 may preferentially attack the carbonyl of the cis-amide form of the substrate, in a stereoelectronically favored manner, to give a tetrahedral oxyanion intermediate, which undergoes N-inversion and/or C-N bond rotation to enable protonation of the leaving group nitrogen. The mechanistic proposals may have consequences for protease inhibition, in particular for the design of high energy intermediate analogues.

Structural analyses on intermediates in serine protease catalysis.,Liu B, Schofield CJ, Wilmouth RC J Biol Chem. 2006 Aug 18;281(33):24024-35. Epub 2006 Jun 5. PMID:16754679<ref>PMID:16754679</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 2bd9" style="background-color:#fffaf0;"></div>

==See Also==
*[[Elastase 3D structures|Elastase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Pancreatic elastase]]
[[Category: Pig]]
[[Category: Liu, B]]
[[Category: Schofield, C J]]
[[Category: Wilmouth, R C]]
[[Category: Hydrolase]]
[[Category: Serine proteinase]]