View source for 1nxn


==SOLUTION STRUCTURE OF CONTRYPHAN-VN==
<StructureSection load='1nxn' size='340' side='right'caption='[[1nxn]]' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1nxn]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Synthetic_construct Synthetic construct]. This structure supersedes the now removed PDB entry [http://oca.weizmann.ac.il/oca-bin/send-pdb?obs=1&id=1n3v 1n3v]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1NXN OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1NXN FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=DTR:D-TRYPTOPHAN'>DTR</scene>, <scene name='pdbligand=NH2:AMINO+GROUP'>NH2</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=1nxn FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1nxn OCA], [https://pdbe.org/1nxn PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1nxn RCSB], [https://www.ebi.ac.uk/pdbsum/1nxn PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1nxn ProSAT]</span></td></tr>
</table>
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The solution structure of contryphan-Vn, a cyclic peptide with a double cysteine S-S bridge and containing a D-tryptophan extracted from the venom of the cone snail Conus ventricosus, has been determined by NMR spectroscopy using a variety of homonuclear and heteronuclear NMR methods and restrained molecular dynamics simulations. The main conformational features of backbone contryphan-Vn are a type IV beta-turn from Gly 1 to Lys 6 and a type I beta-turn from Lys 6 to Cys 9. As already found in other contryphans, one of the two prolines--the Pro4--is mainly in the cis conformation while Pro7 is trans. A small hydrophobic region probably partly shielded from solvent constituted from the close proximity of side chains of Pro7 and Trp8 was observed together with a persistent salt bridge between Asp2 and Lys6, which has been revealed by the diagnostic observation of specific nuclear Overhauser effects. The salt bridge was used as a restraint in the molecular dynamics in vacuum but without inserting explicit electrostatic contribution in the calculations. The backbone of the unique conformational family found of contryphan-Vn superimposes well with those of contryphan-Sm and contryphan-R. This result indicates that the contryphan structural motif represents a robust and conserved molecular scaffold whose main structural determinants are the size of the intercysteine loop and the presence and location in the sequence of the D-Trp and the two Pro residues.

Solution structure of the cyclic peptide contryphan-Vn, a Ca2+-dependent K+ channel modulator.,Eliseo T, Cicero DO, Romeo C, Schinina ME, Massilia GR, Polticelli F, Ascenzi P, Paci M Biopolymers. 2004 Jun 15;74(3):189-98. PMID:15150794<ref>PMID:15150794</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 1nxn" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Synthetic construct]]
[[Category: Ascenzi P]]
[[Category: Cicero DO]]
[[Category: Eliseo T]]
[[Category: Massilia GR]]
[[Category: Paci M]]
[[Category: Polticelli F]]
[[Category: Schinina ME]]