4ZZL

MexR R21W derepressor mutant causing multidrug resistance in P. aeruginosa by mexAB-oprM efflux pump expression


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.19 Å
  • R-Value Free: 0.206 
  • R-Value Work: 0.191 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Mutation-Induced Population Shift in the Mexr Conformational Ensemble Disengages DNA Binding: A Novel Mechanism for Marr Family Derepression.

Anandapadamanaban, M.Pilstal, R.Andresen, C.Trewhella, J.Moche, M.Wallner, B.Sunnerhagen, M.

(2016) Structure 24: 1311

  • DOI: 10.1016/j.str.2016.06.008

  • PubMed Abstract: 
  • MexR is a repressor of the MexAB-OprM multidrug efflux pump operon of Pseudomonas aeruginosa, where DNA-binding impairing mutations lead to multidrug resistance (MDR). Surprisingly, the crystal structure of an MDR-conferring MexR mutant R21W (2.19 Å) ...

    MexR is a repressor of the MexAB-OprM multidrug efflux pump operon of Pseudomonas aeruginosa, where DNA-binding impairing mutations lead to multidrug resistance (MDR). Surprisingly, the crystal structure of an MDR-conferring MexR mutant R21W (2.19 Å) presented here is closely similar to wild-type MexR. However, our extended analysis, by molecular dynamics and small-angle X-ray scattering, reveals that the mutation stabilizes a ground state that is deficient of DNA binding and is shared by both mutant and wild-type MexR, whereas the DNA-binding state is only transiently reached by the more flexible wild-type MexR. This population shift in the conformational ensemble is effected by mutation-induced allosteric coupling of contact networks that are independent in the wild-type protein. We propose that the MexR-R21W mutant mimics derepression by small-molecule binding to MarR proteins, and that the described allosteric model based on population shifts may also apply to other MarR family members.


    Organizational Affiliation

    Division of Chemistry, Department of Physics, Chemistry and Biology, Linköping University, 581 83 Linköping, Sweden.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
MULTIDRUG RESISTANCE OPERON REPRESSOR
A, B
158Pseudomonas aeruginosa (strain ATCC 15692 / DSM 22644 / CIP 104116 / JCM 14847 / LMG 12228 / 1C / PRS 101 / PAO1)Mutation(s): 1 
Gene Names: mexR
Find proteins for P52003 (Pseudomonas aeruginosa (strain ATCC 15692 / DSM 22644 / CIP 104116 / JCM 14847 / LMG 12228 / 1C / PRS 101 / PAO1))
Go to UniProtKB:  P52003
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
GOL
Query on GOL

Download SDF File 
Download CCD File 
B
GLYCEROL
GLYCERIN; PROPANE-1,2,3-TRIOL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.19 Å
  • R-Value Free: 0.206 
  • R-Value Work: 0.191 
  • Space Group: P 32 2 1
Unit Cell:
Length (Å)Angle (°)
a = 84.880α = 90.00
b = 84.880β = 90.00
c = 114.187γ = 120.00
Software Package:
Software NamePurpose
PHASERphasing
SCALAdata scaling
BUSTERrefinement
XDSdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2016-07-27
    Type: Initial release
  • Version 1.1: 2016-08-24
    Type: Database references