View source for 1cnm


==ENHANCEMENT OF CATALYTIC EFFICIENCY OF PROTEINASE K THROUGH EXPOSURE TO ANHYDROUS ORGANIC SOLVENT AT 70 DEGREES CELSIUS==
<StructureSection load='1cnm' size='340' side='right'caption='[[1cnm]], [[Resolution|resolution]] 2.20&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1cnm]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Parengyodontium_album Parengyodontium album]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1CNM OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1CNM 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]] 2.2&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene>, <scene name='pdbligand=CCN:ACETONITRILE'>CCN</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=1cnm FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1cnm OCA], [https://pdbe.org/1cnm PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1cnm RCSB], [https://www.ebi.ac.uk/pdbsum/1cnm PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1cnm ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/PRTK_PARAQ PRTK_PARAQ] Hydrolyzes keratin at aromatic and hydrophobic residues.
== 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/cn/1cnm_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=1cnm ConSurf].
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== Publication Abstract from PubMed ==
The enzyme behavior in anhydrous media has important applications in biotechnology. So far chemical modifications and protein engineering have been used to alter the catalytic power of the enzymes. For the first time, it is demonstrated that an exposure of enzyme to anhydrous organic solvents at optimized high temperature enhances its catalytic power through local changes at the binding region. Six enzymes: proteinase K, wheat germ acid phosphatase, alpha-amylase, beta-glucosidase, chymotrypsin and trypsin have been exposed to acetonitrile at 70 degrees C for three hours. The activities of these enzymes were found to be considerably enhanced. In order to understand the basis of this change in the activity of these enzymes, the structure of one of these treated enzymes, proteinase K has been analyzed in detail using X-ray diffraction method. The overall structure of the enzyme is similar to the native structure in aqueous environment. The hydrogen bonding system of the catalytic triad is intact after the treatment. However, the water structure in the substrate binding site undergoes some rearrangement as some of the water molecules are either displaced or completely absent. The most striking observation concerning the water structure pertains to the complete deletion of the water molecule which occupied the position at the so-called oxyanion hole in the active site of the native enzyme. Three acetonitrile molecules were found in the present structure. All the acetonitrile molecules are located in the recognition site. The sites occupied by acetonitrile molecules are independent of water molecules. The acetonitrile molecules are involved in extensive interactions with the protein atoms. All of them are interlinked through water molecules. The methyl group of one of the acetonitrile molecules (CCN1) interacts simultaneously with the hydrophobic side chains of Leu-96, Ile-107, and Leu-133. The development of such a hydrophobic environment at the recognition site introduces a striking conformation change in Ile-107 by rotating its side chain about C(alpha)--C(beta) bond by 180 degrees to bring about the delta-methyl group within the range of attractive van der Waals interactions with the methyl group of CCN1. A similar change has earlier been observed in proteinase K when it is complexed to a substrate analog lactoferrin fragment.

Enhancement of catalytic efficiency of enzymes through exposure to anhydrous organic solvent at 70 degrees C. Three-dimensional structure of a treated serine proteinase at 2.2 A resolution.,Gupta MN, Tyagi R, Sharma S, Karthikeyan S, Singh TP Proteins. 2000 May 15;39(3):226-34. PMID:10737944<ref>PMID:10737944</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 1cnm" style="background-color:#fffaf0;"></div>

==See Also==
*[[Proteinase 3D structures|Proteinase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Parengyodontium album]]
[[Category: Gupta MN]]
[[Category: Karthikeyan S]]
[[Category: Sharma S]]
[[Category: Singh TP]]
[[Category: Tyagi R]]