1OMN

SOLUTION STRUCTURE OF OMEGA-CONOTOXIN MVIIC, A HIGH AFFINITY OF P-TYPE CALCIUM CHANNELS, USING 1H NMR SPECTROSCOPY AND COMPLETE RELAXATION MATRIX ANALYSIS


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Submitted: 15 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Solution structure of omega-conotoxin MVIIC, a high affinity ligand of P-type calcium channels, using 1H NMR spectroscopy and complete relaxation matrix analysis.

Farr-Jones, S.Miljanich, G.P.Nadasdi, L.Ramachandran, J.Basus, V.J.

(1995) J.Mol.Biol. 248: 106-124

  • DOI: 10.1006/jmbi.1995.0205

  • PubMed Abstract: 
  • We have determined the solution structure of the omega-conotoxin MVIIC from Conus magus by 1H NMR. This conopeptide preferentially blocks P and Q type Ca2+ currents by binding with high affinity to voltage-sensitive Ca2+ channels in neurons. This 26 ...

    We have determined the solution structure of the omega-conotoxin MVIIC from Conus magus by 1H NMR. This conopeptide preferentially blocks P and Q type Ca2+ currents by binding with high affinity to voltage-sensitive Ca2+ channels in neurons. This 26 residue peptide with three disulfide bonds was chemically synthesized and refolded for NMR structural studies. The 1H NMR NOESY spectrum of this peptide was completely assigned, with stereospecific assignments made for 12 of the beta prochiral centers. Complete relaxation matrix analysis using MARDIGRAS was used to obtain initial interproton distances from peak intensities. The correlation time necessary for these calculations was determined by measuring 13C relaxation times using inversely detected natural abundance spectra. Distances were input to DG, which provided 15 starting structures which were then subjected to restrained molecular dynamics calculations using SANDER with the AMBER 91 force field in vacuo. 1H-1H vicinal coupling constants were obtained using a combination of line fitting of both E. COSY and NOESY spectra and used to generate angle restraints that were included explicitly in the restrained molecular dynamics calculations. The final set of the 15 best structures had a backbone rmsd of 0.84 A. The ensemble R1/6 factor calculated by CORMA for the final 15 structures was 11%. The final structure consists of an anti-parallel, triple-stranded beta-sheet, with four turns. In spite of significant differences in amino acid sequence and affinities for calcium channel subtypes, the backbone structure of omega-conotoxin MVIIC is very similar to the previously reported structure of omega-conotoxin GVIA.


    Related Citations: 
    • A New Conus Peptide Ligand for Mammalian Presynaptic Ca2+ Channels
      Hillyard, D.R.,Monje, V.D.,Mintz, I.M.,Cruz, L.J.,Imperial, J.S.,Olivera, B.M.
      (1992) Neuron 9: 69


    Organizational Affiliation

    Department of Pharmaceutical Chemistry, University of California, San Francisco 94143-0446, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
OMEGA-CONOTOXIN M VII C (M SEVEN C)
A
27Conus magusN/A
Find proteins for P37300 (Conus magus)
Go to UniProtKB:  P37300
Small Molecules
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
NH2
Query on NH2
A
NON-POLYMERH2 N

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Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Submitted: 15 
  • Olderado: 1OMN Olderado
Software Package:
Software NamePurpose
AMBERrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1995-12-01
    Type: Initial release
  • Version 1.1: 2008-03-24
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2017-11-29
    Type: Derived calculations, Other