1SXM

SCORPION TOXIN (NOXIUSTOXIN) WITH HIGH AFFINITY FOR VOLTAGE DEPENDENT POTASSIUM CHANNEL AND LOW AFFINITY FOR CALCIUM DEPENDENT POTASSIUM CHANNEL (NMR AT 20 DEGREES, PH3.5, 39 STRUCTURES)


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Submitted: 39 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Determination of the three-dimensional solution structure of noxiustoxin: analysis of structural differences with related short-chain scorpion toxins.

Dauplais, M.Gilquin, B.Possani, L.D.Gurrola-Briones, G.Roumestand, C.Menez, A.

(1995) Biochemistry 34: 16563-16573


  • PubMed Abstract: 
  • The 3D structure of noxiustoxin, the first identified scorpion toxin acting on K+ channels, has been elucidated by NMR and molecular modeling. Thirty-nine solution structures were calculated using 572 distance and 42 dihedral restraints. The average ...

    The 3D structure of noxiustoxin, the first identified scorpion toxin acting on K+ channels, has been elucidated by NMR and molecular modeling. Thirty-nine solution structures were calculated using 572 distance and 42 dihedral restraints. The average atomic rms deviation between the refined structures and the mean structure is 0.75 A for the backbone atoms. Noxiustoxin adopts a alpha/beta scaffold constituted of a three-stranded beta-sheet (residues 2-3, 25-30, 33-38) linked to a helix (residues 10-20) through two disulfide bridges. A comparison between the 3D structure of noxiustoxin and those of other structurally and functionally related scorpion toxins (charybdotoxin, PO5-NH2, kaliotoxin) revealed a bending capacity of the helix and a variability in the relative orientations between the helix and the beta-sheet. These two features highlight the plasticity of the alpha/beta scaffold and offer a structural explanation for the capacity of the fold to accommodate an additional alanine residue in the Gly-x-Cys pattern of a previously proposed consensus sequence [Bontems et al. (1991) Science 254, 1521-1523]. Our structural data also emphasize the possibility that the beta-sheet of NTX is implicated in the capacity of NTX to recognize voltage-dependent K+ channels.


    Organizational Affiliation

    Département d'Ingénierie et d'Etude des Protéines, CE-Saclay, Gif-sur-Yvette, France.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
NOXIUSTOXIN
A
40Centruroides noxiusMutation(s): 0 
Find proteins for P08815 (Centruroides noxius)
Go to UniProtKB:  P08815
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 Submitted: 39 
  • Olderado: 1SXM Olderado
Software Package:
Software NamePurpose
X-PLORrefinement
X-PLORphasing
X-PLORmodel building

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 1996-01-29
    Type: Initial release
  • Version 1.1: 2008-03-24
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance