2FR9

NMR structure of the alpha-conotoxin GI (SER12)-benzoylphenylalanine derivative


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 21 
  • Selection Criteria: structures with the least restraint violations 

wwPDB Validation   3D Report Full Report


This is version 2.0 of the entry. See complete history


Literature

Alpha-Conotoxin GI benzoylphenylalanine derivatives. (1)H-NMR structures and photoaffinity labeling of the Torpedo californica nicotinic acetylcholine receptor.

Kasheverov, I.E.Chiara, D.C.Zhmak, M.N.Maslennikov, I.V.Pashkov, V.S.Arseniev, A.S.Utkin, Y.N.Cohen, J.B.Tsetlin, V.I.

(2006) FEBS J 273: 1373-1388

  • DOI: https://doi.org/10.1111/j.1742-4658.2006.05161.x
  • Primary Citation of Related Structures:  
    2FR9, 2FRB

  • PubMed Abstract: 

    alpha-Conotoxins are small peptides from cone snail venoms that function as nicotinic acetylcholine receptor (nAChR)-competitive antagonists differentiating between nAChR subtypes. Current understanding about the mechanism of these selective interactions is based largely on mutational analyses, which identify amino acids in the toxin and nAChR that determine the energetics of ligand binding. To identify regions of the nAChR involved in alpha-conotoxin binding by use of photoactivated cross-linking, two benzoylphenylalanine (Bpa) analogs of alpha-conotoxin GI, GI(Bpa12) and GI(Bpa4), were synthesized by replacing the respective residues with Bpa, and their (1)H-NMR structures were determined. Both analogs preserved the GI conformation, but only GI(Bpa12) displaced (125)I-labeled GI from the Torpedo californica nAChR. (125)I-labeled GI(Bpa12) bound to two sites on the receptor (K(d) 13 and 1800 nM), and on UV irradiation specifically photolabeled the alpha, gamma and delta subunits. Photolabeling sites were mapped by selective proteolysis and enzymatic deglycosylation, combined with SDS/PAGE, HPLC and Edman degradation. In the alpha subunit, cobratoxin-inhibited incorporation was limited to the 22-kDa fragment beginning at alphaSer173 and containing the agonist-binding site segment C. In the gamma subunit, radioactivity was localized to two distinct peptides containing agonist-binding site segments F and D: nonglycosylated 24-kDa and glycosylated 13-kDa fragments starting at gammaAla167 and gammaAla49, respectively. The labeling of these fragments is discussed in terms of a model of GI(Bpa12) bound to the extracellular domain of the Torpedo nAChR homology model derived from the cryo-electron microscopy structure of Torpedo marmorata nAChR and X-ray crystal structures of snail acetylcholine-binding protein complexes with agonists and antagonists.


  • Organizational Affiliation

    Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.


Macromolecules

Find similar proteins by:  Sequence   |   3D Structure  

Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Alpha-conotoxin GI13Conus geographusMutation(s): 1 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
Sequence Annotations
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  • Reference Sequence
Small Molecules
Modified Residues  1 Unique
IDChains TypeFormula2D DiagramParent
PBF
Query on PBF
A
L-PEPTIDE LINKINGC16 H15 N O3PHE
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 21 
  • Selection Criteria: structures with the least restraint violations 

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2006-05-30
    Type: Initial release
  • Version 1.1: 2008-05-01
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2022-03-09
    Changes: Data collection, Database references, Derived calculations, Experimental preparation, Source and taxonomy
  • Version 2.0: 2023-11-15
    Changes: Atomic model, Data collection