View source for 1wct


==A NOVEL CONOTOXIN FROM CONUS TEXTILE WITH UNUSUAL POST-TRANSLATIONAL MODIFICATIONS REDUCES PRESYNAPTIC CALCIUM INFLUX, NMR, 1 STRUCTURE, GLYCOSYLATED PROTEIN==
<StructureSection load='1wct' size='340' side='right'caption='[[1wct]]' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1wct]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Conus_textile Conus textile]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1WCT OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1WCT FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Solution NMR, 1 model</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=BTR:6-BROMO-TRYPTOPHAN'>BTR</scene>, <scene name='pdbligand=CGU:GAMMA-CARBOXY-GLUTAMIC+ACID'>CGU</scene>, <scene name='pdbligand=GAL:BETA-D-GALACTOSE'>GAL</scene>, <scene name='pdbligand=HYP:4-HYDROXYPROLINE'>HYP</scene>, <scene name='pdbligand=NGA:N-ACETYL-D-GALACTOSAMINE'>NGA</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=1wct FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1wct OCA], [https://pdbe.org/1wct PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1wct RCSB], [https://www.ebi.ac.uk/pdbsum/1wct PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1wct ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/CT5AS_CONTE CT5AS_CONTE] Epsilon-conotoxins act at presynaptic membranes, blocking the calcium channels or G protein-coupled receptors. Causes hyperactivity upon intracranial injection into mice. Causes dorsal fins drooping in fish.<ref>PMID:10318957</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Cone snails are gastropod mollusks of the genus Conus that live in tropical marine habitats. They are predators that paralyze their prey by injection of venom containing a plethora of small, conformationally constrained peptides (conotoxins). We report the identification, characterization, and structure of a gamma-carboxyglutamic acid-containing peptide, conotoxin epsilon-TxIX, isolated from the venom of the molluscivorous cone snail, Conus textile. The disulfide bonding pattern of the four cysteine residues, an unparalleled degree of posttranslational processing including bromination, hydroxylation, and glycosylation define a family of conotoxins that may target presynaptic Ca2+ channels or act on G protein-coupled presynaptic receptors via another mechanism. This conotoxin selectively reduces neurotransmitter release at an Aplysia cholinergic synapse by reducing the presynaptic influx of Ca2+ in a slow and reversible fashion. The three-dimensional structure, determined by two-dimensional 1H NMR spectroscopy, identifies an electronegative patch created by the side chains of two gamma-carboxyglutamic acid residues that extend outward from a cavernous cleft. The glycosylated threonine and hydroxylated proline enclose a localized hydrophobic region centered on the brominated tryptophan residue within the constrained intercysteine region.

A conotoxin from Conus textile with unusual posttranslational modifications reduces presynaptic Ca2+ influx.,Rigby AC, Lucas-Meunier E, Kalume DE, Czerwiec E, Hambe B, Dahlqvist I, Fossier P, Baux G, Roepstorff P, Baleja JD, Furie BC, Furie B, Stenflo J Proc Natl Acad Sci U S A. 1999 May 11;96(10):5758-63. PMID:10318957<ref>PMID:10318957</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 1wct" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Conus textile]]
[[Category: Large Structures]]
[[Category: Baleja JD]]
[[Category: Czerwiec E]]
[[Category: Furie B]]
[[Category: Furie BC]]
[[Category: Hambe B]]
[[Category: Rigby AC]]
[[Category: Stenflo J]]