4MJT

Crystal structure of the oligomeric pore-forming toxin pro-Monalysin


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.85 Å
  • R-Value Free: 0.216 
  • R-Value Work: 0.182 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

X-ray and Cryo-electron Microscopy Structures of Monalysin Pore-forming Toxin Reveal Multimerization of the Pro-form.

Leone, P.Bebeacua, C.Opota, O.Kellenberger, C.Klaholz, B.Orlov, I.Cambillau, C.Lemaitre, B.Roussel, A.

(2015) J.Biol.Chem. 290: 13191-13201

  • DOI: 10.1074/jbc.M115.646109
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • β-Barrel pore-forming toxins (β-PFT), a large family of bacterial toxins, are generally secreted as water-soluble monomers and can form oligomeric pores in membranes following proteolytic cleavage and interaction with cell surface receptors. Monalysi ...

    β-Barrel pore-forming toxins (β-PFT), a large family of bacterial toxins, are generally secreted as water-soluble monomers and can form oligomeric pores in membranes following proteolytic cleavage and interaction with cell surface receptors. Monalysin has been recently identified as a β-PFT that contributes to the virulence of Pseudomonas entomophila against Drosophila. It is secreted as a pro-protein that becomes active upon cleavage. Here we report the crystal and cryo-electron microscopy structure of the pro-form of Monalysin as well as the crystal structures of the cleaved form and of an inactive mutant lacking the membrane-spanning region. The overall structure of Monalysin displays an elongated shape, which resembles those of β-pore-forming toxins, such as Aerolysin, but is devoid of a receptor-binding domain. X-ray crystallography, cryo-electron microscopy, and light-scattering studies show that pro-Monalysin forms a stable doughnut-like 18-mer complex composed of two disk-shaped nonamers held together by N-terminal swapping of the pro-peptides. This observation is in contrast with the monomeric pro-form of the other β-PFTs that are receptor-dependent for membrane interaction. The membrane-spanning region of pro-Monalysin is fully buried in the center of the doughnut, suggesting that upon cleavage of pro-peptides, the two disk-shaped nonamers can, and have to, dissociate to leave the transmembrane segments free to deploy and lead to pore formation. In contrast with other toxins, the delivery of 18 subunits at once, nearby the cell surface, may be used to bypass the requirement of receptor-dependent concentration to reach the threshold for oligomerization into the pore-forming complex.


    Organizational Affiliation

    From the CNRS, Architecture et Fonction des Macromolécules Biologiques (AFMB), Unité Mixte de Recherche (UMR) 7257, 13288 Marseille, France, the Aix-Marseille Université, Architecture et Fonction des Macromolécules Biologiques, UMR 7257, 13288 Marseille, France.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
MONALYSIN
A, B, C, D, E, F, G, H, I
236Pseudomonas entomophila (strain L48)Mutation(s): 0 
Gene Names: mnl
Find proteins for Q1I8U1 (Pseudomonas entomophila (strain L48))
Go to UniProtKB:  Q1I8U1
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Monalysin
J, K, L, M, N, O, P, Q, R
27Pseudomonas entomophila (strain L48)Mutation(s): 0 
Gene Names: mnl
Find proteins for Q1I8U1 (Pseudomonas entomophila (strain L48))
Go to UniProtKB:  Q1I8U1
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

Download SDF File 
Download CCD File 
A, B, C, D, E, F, G, H, I
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.85 Å
  • R-Value Free: 0.216 
  • R-Value Work: 0.182 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 162.400α = 90.00
b = 146.200β = 122.80
c = 144.320γ = 90.00
Software Package:
Software NamePurpose
SHARPphasing
ADSCdata collection
SCALAdata scaling
BUSTERrefinement
XDSdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2013-09-04 
  • Released Date: 2015-03-11 
  • Deposition Author(s): Leone, P., Roussel, A.

Revision History 

  • Version 1.0: 2015-03-11
    Type: Initial release
  • Version 1.1: 2015-04-15
    Type: Database references
  • Version 1.2: 2015-04-22
    Type: Database references
  • Version 1.3: 2015-06-10
    Type: Database references