Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 50 
  • Conformers Submitted: 10 
  • Selection Criteria: LEAST RESTRAINT VIOLATION 

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This is version 1.4 of the entry. See complete history


Solution structure of alpha-conotoxin ImI by 1H nuclear magnetic resonance.

Gehrmann, J.Daly, N.L.Alewood, P.F.Craik, D.J.

(1999) J Med Chem 42: 2364-2372

  • DOI: https://doi.org/10.1021/jm990114p
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    alpha-Conotoxin ImI derives from the venom of Conus imperialis and is the first and only small-peptide ligand that selectively binds to the neuronal alpha7 homopentameric subtype of the nicotinic acetylcholine receptor (nAChR). This receptor subtype is a possible drug target for several neurological disorders. The cysteines are connected in the pairs Cys2-Cys8 and Cys3-Cys12. To date it is the only alpha-conotoxin with a 4/3 residue spacing between the cysteines. The structure of ImI has been determined by 1H NMR spectroscopy in aqueous solution. The NMR structure is of high quality, with a backbone pairwise rmsd of 0.34 A for a family of 19 structures, and comprises primarily a series of nested beta turns. Addition of organic solvent does not perturb the solution structure. The first eight residues of ImI are identical to the larger, but related, conotoxin EpI and adopt a similar structure, despite a truncated second loop. Residues important for binding of ImI to the alpha7 nAChR are all clustered on one face of the molecule. Once further binding data for EpI and ImI are available, the ImI structure will allow for design of novel alpha7 nAChR-specific agonists and antagonists with a wide range of potential pharmaceutical applications.

  • Organizational Affiliation

    Centre for Drug Design and Development, University of Queensland, Brisbane, Queensland 4072, Australia.


Find similar proteins by:  Sequence   |   3D Structure  

Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Find proteins for P50983 (Conus imperialis)
Explore P50983 
Go to UniProtKB:  P50983
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UniProt GroupP50983
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 50 
  • Conformers Submitted: 10 
  • Selection Criteria: LEAST RESTRAINT VIOLATION 

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1999-05-27
    Type: Initial release
  • Version 1.1: 2008-04-26
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2022-02-16
    Changes: Data collection, Database references, Derived calculations
  • Version 1.4: 2023-12-27
    Changes: Data collection