5JAA

Crystal structure of the HigBA2 toxin-antitoxin complex


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.993 Å
  • R-Value Free: 0.248 
  • R-Value Work: 0.200 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Ribosome-dependent Vibrio cholerae mRNAse HigB2 is regulated by a beta-strand sliding mechanism.

Hadzi, S.Garcia-Pino, A.Haesaerts, S.Jurenas, D.Gerdes, K.Lah, J.Loris, R.

(2017) Nucleic Acids Res. 45: 4972-4983

  • DOI: 10.1093/nar/gkx138
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Toxin-antitoxin (TA) modules are small operons involved in bacterial stress response and persistence. higBA operons form a family of TA modules with an inverted gene organization and a toxin belonging to the RelE/ParE superfamily. Here, we present th ...

    Toxin-antitoxin (TA) modules are small operons involved in bacterial stress response and persistence. higBA operons form a family of TA modules with an inverted gene organization and a toxin belonging to the RelE/ParE superfamily. Here, we present the crystal structures of chromosomally encoded Vibrio cholerae antitoxin (VcHigA2), toxin (VcHigB2) and their complex, which show significant differences in structure and mechanisms of function compared to the higBA module from plasmid Rts1, the defining member of the family. The VcHigB2 is more closely related to Escherichia coli RelE both in terms of overall structure and the organization of its active site. VcHigB2 is neutralized by VcHigA2, a modular protein with an N-terminal intrinsically disordered toxin-neutralizing segment followed by a C-terminal helix-turn-helix dimerization and DNA binding domain. VcHigA2 binds VcHigB2 with picomolar affinity, which is mainly a consequence of entropically favorable de-solvation of a large hydrophobic binding interface and enthalpically favorable folding of the N-terminal domain into an α-helix followed by a β-strand. This interaction displaces helix α3 of VcHigB2 and at the same time induces a one-residue shift in the register of β-strand β3, thereby flipping the catalytically important Arg64 out of the active site.


    Organizational Affiliation

    Structural Biology Brussels, Department of Biotechnology, Vrije Universiteit Brussel, B-1050 Brussel, Belgium.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Antitoxin igA-2
A, B
103Vibrio cholerae serotype O1 (strain ATCC 39315 / El Tor Inaba N16961)Mutation(s): 0 
Gene Names: higA-2
Find proteins for Q9KMA5 (Vibrio cholerae serotype O1 (strain ATCC 39315 / El Tor Inaba N16961))
Go to UniProtKB:  Q9KMA5
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Toxin HigB-2
C, D
111Vibrio cholerae serotype O1 (strain ATCC 39315 / El Tor Inaba N16961)Mutation(s): 0 
Gene Names: higB-2
Find proteins for Q9KMA6 (Vibrio cholerae serotype O1 (strain ATCC 39315 / El Tor Inaba N16961))
Go to UniProtKB:  Q9KMA6
Small Molecules
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
MSE
Query on MSE
A, B, C, D
L-PEPTIDE LINKINGC5 H11 N O2 SeMET
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.993 Å
  • R-Value Free: 0.248 
  • R-Value Work: 0.200 
  • Space Group: P 21 21 2
Unit Cell:
Length (Å)Angle (°)
a = 129.000α = 90.00
b = 119.800β = 90.00
c = 33.400γ = 90.00
Software Package:
Software NamePurpose
XDSdata reduction
PHENIXrefinement
XSCALEdata scaling
PDB_EXTRACTdata extraction
SHELXphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2016-04-12 
  • Released Date: 2017-04-05 
  • Deposition Author(s): Hadzi, S., Loris, R.

Revision History 

  • Version 1.0: 2017-04-05
    Type: Initial release
  • Version 1.1: 2017-05-17
    Type: Database references