1AGT

SOLUTION STRUCTURE OF THE POTASSIUM CHANNEL INHIBITOR AGITOXIN 2: CALIPER FOR PROBING CHANNEL GEOMETRY


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Submitted: 17 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Solution structure of the potassium channel inhibitor agitoxin 2: caliper for probing channel geometry.

Krezel, A.M.Kasibhatla, C.Hidalgo, P.MacKinnon, R.Wagner, G.

(1995) Protein Sci. 4: 1478-1489

  • DOI: 10.1002/pro.5560040805

  • PubMed Abstract: 
  • The structure of the potassium channel blocker agitoxin 2 was solved by solution NMR methods. The structure consists of a triple-stranded antiparallel beta-sheet and a single helix covering one face of the beta-sheet. The cysteine side chains connect ...

    The structure of the potassium channel blocker agitoxin 2 was solved by solution NMR methods. The structure consists of a triple-stranded antiparallel beta-sheet and a single helix covering one face of the beta-sheet. The cysteine side chains connecting the beta-sheet and the helix form the core of the molecule. One edge of the beta-sheet and the adjacent face of the helix form the interface with the Shaker K+ channel. The fold of agitoxin is homologous to the previously determined folds of scorpion venom toxins. However, agitoxin 2 differs significantly from the other channel blockers in the specificity of its interactions. This study was thus focused on a precise characterization of the surface residues at the face of the protein interacting with the Shaker K+ channel. The rigid toxin molecule can be used to estimate dimensions of the potassium channel. Surface-exposed residues, Arg24, Lys27, and Arg31 of the beta-sheet, have been identified from mutagenesis studies as functionally important for blocking the Shaker K+ channel. The sequential and spatial locations of Arg24 and Arg31 are not conserved among the homologous toxins. Knowledge on the details of the channel-binding sites of agitoxin 2 formed a basis for site-directed mutagenesis studies of the toxin and the K+ channel sequences. Observed interactions between mutated toxin and channel are being used to elucidate the channel structure and mechanisms of channel-toxin interactions.


    Organizational Affiliation

    Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
AGITOXIN 2
A
38Leiurus quinquestriatus hebraeusN/A
Find proteins for P46111 (Leiurus quinquestriatus hebraeus)
Go to UniProtKB:  P46111
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Submitted: 17 
  • Olderado: 1AGT Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1995-07-10
    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