1PX9

Solution structure of the native CnErg1 Ergtoxin, a highly specific inhibitor of HERG channel


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 10 
  • Conformers Submitted: 
  • Selection Criteria: structures with acceptable covalent geometry, structures with favorable non-bond energy, 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

Exploring structural features of the interaction between the scorpion toxinCnErg1 and ERG K+ channels.

Frenal, K.Xu, C.Q.Wolff, N.Wecker, K.Gurrola, G.B.Zhu, S.Y.Chi, C.W.Possani, L.D.Tytgat, J.Delepierre, M.

(2004) Proteins 56: 367-375

  • DOI: 10.1002/prot.20102
  • Primary Citation of Related Structures:  
    1PX9

  • PubMed Abstract: 
  • The gamma-KTx-type scorpion toxins specific for K+ channels were found to interact with ERG channels on the turret region, while alpha-KTx3.2 Agitoxin-2 binds to the pore region of the Shaker K+ channel, and alpha-KTx5.3 BmP05 binds to the intermediate region of the small-conductance calcium-activated K-channel (SK(Ca)) ...

    The gamma-KTx-type scorpion toxins specific for K+ channels were found to interact with ERG channels on the turret region, while alpha-KTx3.2 Agitoxin-2 binds to the pore region of the Shaker K+ channel, and alpha-KTx5.3 BmP05 binds to the intermediate region of the small-conductance calcium-activated K-channel (SK(Ca)). In order to explore the critical residues for gamma-KTx binding, we determined the NMR structure of native gamma-KTx1.1 (CnErg1), a 42 amino acid residues scorpion toxin isolated from the venom of the Mexican scorpion Centruroïdes noxius Hoffmann, and we used computational evolutionary trace (ET) analysis to predict possible structural and functional features of interacting surfaces. The 1H-NMR three-dimensional solution structure of native ergtoxin (CnErg1) was solved using a total of 452 distance constraints, 13 3J(NH-Halpha) and 10 hydrogen bonds. The structure is characterized by 2 segments of alpha-helices and a triple-stranded antiparallel beta-sheet stabilized by 4 disulfide bridges. The ET and structural analysis provided indication of the presence of two important amino acid residue clusters, one hydrophobic and the other hydrophilic, that should be involved in the surface contact between the toxin and the channel. Some features of the proposed interacting surface are discussed.


    Organizational Affiliation

    Unité de RMN des Biomolécules URA 2185 CNRS, Institut Pasteur, Paris, France.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
ergtoxinA42Centruroides noxiusMutation(s): 0 
UniProt
Find proteins for Q86QT3 (Centruroides noxius)
Explore Q86QT3 
Go to UniProtKB:  Q86QT3
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 10 
  • Conformers Submitted: 
  • Selection Criteria: structures with acceptable covalent geometry, structures with favorable non-bond energy, structures with the least restraint violations, structures with the lowest energy 
  • OLDERADO: 1PX9 Olderado

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2004-06-22
    Type: Initial release
  • Version 1.1: 2008-04-29
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance