1IAZ

EQUINATOXIN II

• PDB DOI: https://doi.org/10.2210/pdb1IAZ/pdb

• Classification: TOXIN
• Organism(s): Actinia equina
• Expression System: Escherichia coli
• Mutation(s): No 
• Membrane Protein: Yes  OPM


• Deposited: 2001-03-24 Released: 2001-04-04 
• Deposition Author(s): Athanasiadis, A., Anderluh, G., Macek, P., Turk, D.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 0.235 
• R-Value Work: 0.185 
• R-Value Observed: 0.190 

Literature

Crystal structure of the soluble form of equinatoxin II, a pore-forming toxin from the sea anemone Actinia equina.

Athanasiadis, A., Anderluh, G., Macek, P., Turk, D.

(2001) Structure 9: 341-346

• PubMed: 11525171 
• DOI: https://doi.org/10.1016/s0969-2126(01)00592-5
• Primary Citation of Related Structures:  
  1IAZ


• PubMed Abstract: 
  

  Membrane pore-forming toxins have a remarkable property: they adopt a stable soluble form structure, which, when in contact with a membrane, undergoes a series of transformations, leading to an active, membrane-bound form. In contrast to bacterial toxins, no structure of a pore-forming toxin from an eukaryotic organism has been determined so far, an indication that structural studies of equinatoxin II (EqtII) may unravel a novel mechanism.

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Organizational Affiliation: 

Department of Biochemistry and Molecular Biology, Jozef Stefan Institute, Ljubljana, Slovenia.

Biological Assembly 1  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 40.75 kDa 
• Atom Count: 3,186 
• Modelled Residue Count: 350 
• Deposited Residue Count: 358 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
EQUINATOXIN II	A, B	179	Actinia equina	Mutation(s): 0  Membrane Entity: Yes
UniProt
Find proteins for P61914 (Actinia equina) Explore P61914  Go to UniProtKB:  P61914

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
SO4	C [auth A], D [auth A], E [auth A], F [auth A], G [auth A], H [auth A], I [auth A], J [auth B], K [auth B], L [auth B], M [auth B]	SULFATE ION O4 S QAOWNCQODCNURD-UHFFFAOYSA-L

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.90 Å
• R-Value Free: 0.235 
• R-Value Work: 0.185 
• R-Value Observed: 0.190 
• Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 81.62	α = 90
b = 129.04	β = 90
c = 31.76	γ = 90

Software Package:

Software Name	Purpose
MOSFLM	data reduction
SCALA	data scaling
SHARP	phasing
MAIN	refinement
CCP4	data scaling

Structure Validation

Entry History 

Deposition Data

• Released Date: 2001-04-04 
Deposition Author(s): Athanasiadis, A., Anderluh, G., Macek, P., Turk, D.

Revision History  

• Version 1.0: 2001-04-04
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2018-10-03
  Changes: Advisory, Data collection
• Version 1.4: 2024-02-07
  Changes: Advisory, Data collection, Database references, Derived calculations