View source for 1ad7


==NMR STRUCTURE OF METAL-FREE CONANTOKIN G, 1 STRUCTURE==
<StructureSection load='1ad7' size='340' side='right'caption='[[1ad7]]' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[1ad7]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Conus_geographus Conus geographus]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1AD7 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1AD7 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=CGU:GAMMA-CARBOXY-GLUTAMIC+ACID'>CGU</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=1ad7 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1ad7 OCA], [https://pdbe.org/1ad7 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1ad7 RCSB], [https://www.ebi.ac.uk/pdbsum/1ad7 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1ad7 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/CKG_CONGE CKG_CONGE] Conantokins inhibit N-methyl-D-aspartate (NMDA) receptors. This toxin is selective for the NR2B/GRIN2B subunit. Induces sleep-like symptoms in young mice and hyperactivity in older mice.<ref>PMID:2165278</ref> 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Conantokin G is a gamma-carboxyglutamic acid-containing conotoxin from the venom of the marine cone snail Conus geographus. The 17-residue peptide, which contains five gamma-carboxyglutamic acid (Gla) residues and an amidated C-terminal asparagine amide, was synthesized chemically in a form identical to the natural conantokin G. To gain insight into the role of gamma-carboxyglutamic acid in the structure of this peptide, we determined the three-dimensional structure of conantokin G by 1H NMR and compared its structure to other conotoxins and to the gamma-carboxyglutamic acid-containing regions of the vitamin K-dependent blood-clotting proteins. Complete resonance assignments were made by two-dimensional 1H NMR spectroscopy in the absence of metal ions. NOE cross-peaks d(alphaN), d(NN), and d(betaN) provided interproton distance information, and vicinal spin-spin coupling constants 3J(HN alpha) were used to calculate phi torsion angles. Distance geometry and simulated annealing methods were used to derive 20 convergent structures from a set of 227 interproton distance restraints and 13 torsion angle measurements. The backbone rmsd to the geometric average for 20 final structures is 0.8 +/- 0.1 A. Conantokin G consists of a structured region commencing at Gla 3 and extending through arginine 13. This structure includes a partial loop centered around Gla 3 and Gla 4, a distorted type I turn between glutamine 6 and glutamine 9, and two type I turns involving Gla 10, leucine 11, and isoleucine 12 and arginine 13. Together, these two turns define approximately 1.6 turns of a distorted 3(10) helix. The observed structure possesses structural elements similar to those seen in the disulfide-linked conotoxins.

Three-dimensional structure of a gamma-carboxyglutamic acid-containing conotoxin, conantokin G, from the marine snail Conus geographus: the metal-free conformer.,Rigby AC, Baleja JD, Furie BC, Furie B Biochemistry. 1997 Jun 10;36(23):6906-14. PMID:9188685<ref>PMID:9188685</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 1ad7" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Conus geographus]]
[[Category: Large Structures]]
[[Category: Baleja JD]]
[[Category: Furie B]]
[[Category: Furie BC]]
[[Category: Rigby AC]]