View source for 2kmr


==Solution structure of intermediate IIc of Leech-derived tryptase inhibitor, LDTI.==
<StructureSection load='2kmr' size='340' side='right'caption='[[2kmr]], [[NMR_Ensembles_of_Models | 20 NMR models]]' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[2kmr]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Hirme Hirme]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2KMR OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2KMR FirstGlance]. <br>
</td></tr><tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[2kmo|2kmo]], [[2kmp|2kmp]], [[2kmq|2kmq]]</div></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=2kmr FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2kmr OCA], [https://pdbe.org/2kmr PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2kmr RCSB], [https://www.ebi.ac.uk/pdbsum/2kmr PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2kmr ProSAT]</span></td></tr>
</table>
== Function ==
[[https://www.uniprot.org/uniprot/LDTI_HIRME LDTI_HIRME]] Acts as an inhibitor of human tryptase, trypsin and chymotrypsin. Probably acts to block host defense mechanisms. 
== 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/km/2kmr_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=2kmr ConSurf].
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== Publication Abstract from PubMed ==
Protein folding mechanisms have remained elusive mainly because of the transient nature of intermediates. Leech-derived tryptase inhibitor (LDTI) is a Kazal-type serine proteinase inhibitor that is emerging as an attractive model for folding studies. It comprises 46 amino acid residues with three disulfide bonds, with one located inside a small triple-stranded antiparallel beta-sheet and with two involved in a cystine-stabilized alpha-helix, a motif that is widely distributed in bioactive peptides. Here, we analyzed the oxidative folding and reductive unfolding of LDTI by chromatographic and disulfide analyses of acid-trapped intermediates. It folds and unfolds, respectively, via sequential oxidation and reduction of the cysteine residues that give rise to a few 1- and 2-disulfide intermediates. Species containing two native disulfide bonds predominate during LDTI folding (IIa and IIc) and unfolding (IIa and IIb). Stop/go folding experiments demonstrate that only intermediate IIa is productive and oxidizes directly into the native form. The NMR structures of acid-trapped and further isolated IIa, IIb, and IIc reveal global folds similar to that of the native protein, including a native-like canonical inhibitory loop. Enzyme kinetics shows that both IIa and IIc are inhibitory-active, which may substantially reduce proteolysis of LDTI during its folding process. The results reported show that the kinetics of the folding reaction is modulated by the specific structural properties of the intermediates and together provide insights into the interdependence of conformational folding and the assembly of native disulfides during oxidative folding.

Deciphering the structural basis that guides the oxidative folding of leech-derived tryptase inhibitor.,Pantoja-Uceda D, Arolas JL, Aviles FX, Santoro J, Ventura S, Sommerhoff CP J Biol Chem. 2009 Dec 18;284(51):35612-20. Epub . PMID:19820233<ref>PMID:19820233</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 2kmr" style="background-color:#fffaf0;"></div>

==See Also==
*[[Tryptase inhibitor|Tryptase inhibitor]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Hirme]]
[[Category: Large Structures]]
[[Category: Pantoja-Uceda, D]]
[[Category: Santoro, J]]
[[Category: Disulfide bond]]
[[Category: Hydrolase]]
[[Category: Protease inhibitor]]
[[Category: Serine protease inhibitor]]