View source for 3bg4


==The crystal structure of guamerin in complex with chymotrypsin and the development of an elastase-specific inhibitor==
<StructureSection load='3bg4' size='340' side='right'caption='[[3bg4]], [[Resolution|resolution]] 2.50&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[3bg4]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Bos_taurus Bos taurus] and [https://en.wikipedia.org/wiki/Hirudo_nipponia Hirudo nipponia]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3BG4 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=3BG4 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]] 2.5&#8491;</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=3bg4 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3bg4 OCA], [https://pdbe.org/3bg4 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=3bg4 RCSB], [https://www.ebi.ac.uk/pdbsum/3bg4 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=3bg4 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/GUAM_HIRNI GUAM_HIRNI] Inhibits mammalian elastases.
== 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/bg/3bg4_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=3bg4 ConSurf].
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== Publication Abstract from PubMed ==
Guamerin, a canonical serine protease inhibitor from Hirudo nipponia, was identified as an elastase-specific inhibitor and has potential application in various diseases caused by elevated elastase concentration. However, the application of guamerin is limited because it also shows inhibitory activity against other proteases. To improve the selectivity of guamerin as an elastase inhibitor, it is essential to understand the binding mode of the inhibitor to elastase and to other proteases. For this purpose, we determined the crystal structure of guamerin in complex with chymotrypsin at 2.5 A resolution. The binding mode of guamerin on elastase was explored from the model structure of guamerin/elastase. Guamerin binds to the hydrophobic pocket of the protease in a substrate-like manner using its binding loop. In order to improve the binding selectivity of guamerin to elastase, several residues in the binding loop were mutated and the inhibitory activities of the mutants against elastase and chymotrypsin were monitored. The substitution of the Met36 residue for Ala in the P1 site increased the inhibitory activity against elastase up to 14-fold, while the same mutant showed 7-fold decreased activity against chymotrypsin compared to the wild-type guamerin. Furthermore, the M36A guamerin mutant more effectively protected endothelial cells against cell damage caused by elastase than the wild-type guamerin.

The crystal structure of guamerin in complex with chymotrypsin and the development of an elastase-specific inhibitor.,Kim H, Chu TT, Kim DY, Kim DR, Nguyen CM, Choi J, Lee JR, Hahn MJ, Kim KK J Mol Biol. 2008 Feb 8;376(1):184-92. Epub 2007 Dec 4. PMID:18155725<ref>PMID:18155725</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 3bg4" style="background-color:#fffaf0;"></div>

==See Also==
*[[Chymotrypsin 3D structures|Chymotrypsin 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Bos taurus]]
[[Category: Hirudo nipponia]]
[[Category: Large Structures]]
[[Category: Choi J]]
[[Category: Chu TTT]]
[[Category: Hahn MJ]]
[[Category: Kim DR]]
[[Category: Kim DY]]
[[Category: Kim H]]
[[Category: Kim KK]]
[[Category: Lee JR]]
[[Category: Nguyen CMT]]