1TCG

STRUCTURE-ACTIVITY RELATIONSHIPS OF MU-CONOTOXIN GIIIA: STRUCTURE DETERMINATION OF ACTIVE AND INACTIVE SODIUM CHANNEL BLOCKER PEPTIDES BY NMR AND SIMULATED ANNEALING CALCULATIONS


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Submitted: 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Structure-activity relationships of mu-conotoxin GIIIA: structure determination of active and inactive sodium channel blocker peptides by NMR and simulated annealing calculations.

Wakamatsu, K.Kohda, D.Hatanaka, H.Lancelin, J.M.Ishida, Y.Oya, M.Nakamura, H.Inagaki, F.Sato, K.

(1992) Biochemistry 31: 12577-12584

  • DOI: https://doi.org/10.1021/bi00165a006
  • Primary Citation of Related Structures:  
    1TCG, 1TCH, 1TCJ, 1TCK

  • PubMed Abstract: 

    A synthetic replacement study of the amino acid residues of mu-conotoxin GIIIA, a peptide blocker for muscle sodium channels, has recently shown that the conformation formed by three disulfide bridges and the molecular basicity, especially the one around the Arg13 residue, are important for blocking activity. In the present study, we determined the three-dimensional structure of an inactive analog, [Ala13]mu-conotoxin GIIIA, and refined that of the native toxin by NMR spectroscopy combined with simulated annealing calculations. The atomic root-mean-square difference of the mutant from the native conotoxin was 0.62 A for the backbone atoms (N, C alpha, C') of all residues except for the two terminal residues. The observation that the replacement of Arg13 by Ala13 does not significantly change the molecular conformation suggests that the loss of activity is not due to the conformational change but to the direct interaction of the essential Arg13 residue with the sodium channel molecules. In the determined structure, important residues for the activity, Arg13, Lys16, Hyp(hydroxyproline)17, and Arg19, are clustered on one side of the molecule, an observation which suggests that this face of the molecule associates with the receptor site of sodium channels. The hydroxyl group of Hyp17 is suggested to interact with the channel site with which the essential hydroxyl groups of tetrodotoxin and saxitoxin interact.


  • Organizational Affiliation

    Faculty of Engineering, Gunma University, Japan.


Macromolecules

Find similar proteins by:  Sequence   |   3D Structure  

Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
MU-CONOTOXIN GIIIA23Conus geographusMutation(s): 0 
UniProt
Find proteins for P01523 (Conus geographus)
Explore P01523 
Go to UniProtKB:  P01523
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP01523
Sequence Annotations
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  • Reference Sequence
Small Molecules
Modified Residues  1 Unique
IDChains TypeFormula2D DiagramParent
HYP
Query on HYP
A
L-PEPTIDE LINKINGC5 H9 N O3PRO
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Submitted: 

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1994-01-31
    Type: Initial release
  • Version 1.1: 2008-03-24
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2017-11-29
    Changes: Derived calculations, Other