1TZQ

Crystal structure of the equinatoxin II 8-69 double cysteine mutant


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.274 
  • R-Value Work: 0.192 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Pore formation by equinatoxin, a eukaryotic pore-forming toxin, requires a flexible N-terminal region and a stable beta-sandwich

Kristan, K.Podlesek, Z.Hojnik, V.Gutierrez-Aguirre, I.Guncar, G.Turk, D.A.Gonzalez-Manas, J.M.Lakey, J.H.Macek, P.Anderluh, G.

(2004) J.Biol.Chem. 279: 46509-46517

  • DOI: 10.1074/jbc.M406193200

  • PubMed Abstract: 
  • Actinoporins are eukaryotic pore-forming proteins that create 2-nm pores in natural and model lipid membranes by the self-association of four monomers. The regions that undergo conformational change and form part of the transmembrane pore are current ...

    Actinoporins are eukaryotic pore-forming proteins that create 2-nm pores in natural and model lipid membranes by the self-association of four monomers. The regions that undergo conformational change and form part of the transmembrane pore are currently being defined. It was shown recently that the N-terminal region (residues 10-28) of equinatoxin, an actinoporin from Actinia equina, participates in building of the final pore wall. Assuming that the pore is formed solely by a polypeptide chain, other parts of the toxin should constitute the conductive channel and here we searched for these regions by disulfide scanning mutagenesis. Only double cysteine mutants where the N-terminal segment 1-30 was attached to the beta-sandwich exhibited reduced hemolytic activity upon disulfide formation, showing that other parts of equinatoxin, particularly the beta-sandwich and importantly the C-terminal alpha-helix, do not undergo large conformational rearrangements during the pore formation. The role of the beta-sandwich stability was independently assessed via destabilization of a part of its hydrophobic core by mutations of the buried Trp117. These mutants were considerably less stable than the wild-type but exhibited similar or slightly lower permeabilizing activity. Collectively these results show that a flexible N-terminal region and stable beta-sandwich are pre-requisite for proper pore formation by the actinoporin family.


    Organizational Affiliation

    Department of Biology, Biotechnical Faculty, University of Ljubljana, Vecna pot 111, 1000 Ljubljana, Slovenia.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Equinatoxin II
A
175Actinia equinaMutation(s): 2 
Find proteins for P61914 (Actinia equina)
Go to UniProtKB:  P61914
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.274 
  • R-Value Work: 0.192 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 36.585α = 90.00
b = 52.682β = 92.26
c = 39.789γ = 90.00
Software Package:
Software NamePurpose
AMoREphasing
SCALEPACKdata scaling
HKL-2000data collection
MAINrefinement
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2004-09-28
    Type: Initial release
  • Version 1.1: 2008-04-30
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance