1G2G

MINIMAL CONFORMATION OF THE ALPHA-CONOTOXIN IMI FOR THE ALPHA7 NEURONAL NICOTINIC ACETYLCHOLINE RECEPTOR RECOGNITION


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 60 
  • Conformers Submitted: 30 
  • Selection Criteria: structures with the least restraint violations,structures with the lowest energy 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Minimal conformation of the alpha-conotoxin ImI for the alpha7 neuronal nicotinic acetylcholine receptor recognition: correlated CD, NMR and binding studies.

Lamthanh, H.Jegou-Matheron, C.Servent, D.Menez, A.Lancelin, J.M.

(1999) FEBS Lett. 454: 293-298

  • Also Cited By: 2MOA

  • PubMed Abstract: 
  • The alpha-ImI conotoxin, a selective potent inhibitor of the mammalian neuronal alpha7 nicotinic acetylcholine receptor (n-AchR), was shown by point mutation or by L-alanine scanning to display two regions essential for bioactivity: the active site A ...

    The alpha-ImI conotoxin, a selective potent inhibitor of the mammalian neuronal alpha7 nicotinic acetylcholine receptor (n-AchR), was shown by point mutation or by L-alanine scanning to display two regions essential for bioactivity: the active site Asp5-Pro6-Arg7 in the first loop and Trp10 in the second loop. The deletion of the Cys3,Cys12 disulfide bond in the alpha-ImI scaffold, e.g. peptide II, had no effect on its binding affinity. CD spectra, NMR studies and structure calculations were carried out on the wild type alpha-ImI, the weakest analog (R7A) and peptide II (equipotent to alpha-ImI) in order to point out the conformational differences between these compounds. Then, an attempt to correlate the conformational data and the affinity results was proposed. CD and NMR data were identical for the R7A analog and alpha-ImI, revealing the crucial functional role of the Arg7 side chain. On the other hand, the scaffold of the first loop in peptide II was shown by NMR to represent the minimal conformation for the optimal interaction of the toxin with the neuronal alpha7 n-AchR. Last, the beta-turn forming property of the 6th residue (Pro) in the active site of the alpha-ImI can be correlated with its affinity.


    Related Citations: 
    • NMR Solution Structure of alpha-Conotoxin ImI and Comparison to other Conotoxins Specific for Neuronal Nicotinic Acetylcholine Receptors
      Rogers, J.P.,Luginbuhl, P.,Shen, G.S.,McCabe, R.T.,Stevens, R.C.,Wemmer, D.E.
      (1999) Biochemistry 38: 3874
    • A Nicotinic Acetylcholine Receptor Ligand of Unique Specificity, alpha-Conotoxin ImI
      McIntosh, J.M.,Yoshikami, D.,Mahe, E.,Nielsen, D.B.,Rivier, J.E.,Gray, W.R.,Olivera, B.M.
      (1994) J.Biol.Chem. 269: 16733
    • Identification of Residues in the Neuronal alpha7 Acetylcholine Receptor that Confer Selectivity for Conotoxin ImI
      Quiram, P.A.,Sine, S.M.
      (1998) J.Biol.Chem. 273: 11001
    • Functional Determinants by which Snake and Cone Snail Toxins Block the alpha 7 Neuronal Nicotinic Acetylcholine Receptors
      Servent, D.,Lamthanh, H.,Antil, S.,Bertrand, D.,Corringer, P.J.,Changeux, J.P.,Menez, A.
      (1998) J.Physiol.(Paris) 92: 107
    • NMR Spatial Structure of alpha-Conotoxin ImI Reveals a Common Scaffold in Snail and Snake Toxins Recognizing Neuronal Nicotinic Acetylcholine Receptors
      Maslennikov, I.V.,Shenkarev, Z.O.,Zhmak, M.N.,Ivanov, V.T.,Methfessel, C.,Tsetlin, V.I.,Arseniev, A.S.
      (1999) FEBS Lett. 444: 275


    Organizational Affiliation

    CEA, Département d'Ingénierie et d'Etudes des Protéines, Gif sur Yvette, France. lamthanh@dsvidf.cea.fr




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
ALPHA-CONOTOXIN IMI
A
13Conus imperialisN/A
Find proteins for P50983 (Conus imperialis)
Go to UniProtKB:  P50983
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 Calculated: 60 
  • Conformers Submitted: 30 
  • Selection Criteria: structures with the least restraint violations,structures with the lowest energy 
  • Olderado: 1G2G Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2000-11-08
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance