4JVC

Crystal structure of PqsR co-inducer binding domain


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.5 Å
  • R-Value Free: 0.267 
  • R-Value Work: 0.222 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structural basis for native agonist and synthetic inhibitor recognition by the Pseudomonas aeruginosa quorum sensing regulator PqsR (MvfR).

Ilangovan, A.Fletcher, M.Rampioni, G.Pustelny, C.Rumbaugh, K.Heeb, S.Camara, M.Truman, A.Chhabra, S.R.Emsley, J.Williams, P.

(2013) Plos Pathog. 9: e1003508-e1003508

  • DOI: 10.1371/journal.ppat.1003508
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Bacterial populations co-ordinate gene expression collectively through quorum sensing (QS), a cell-to-cell communication mechanism employing diffusible signal molecules. The LysR-type transcriptional regulator (LTTR) protein PqsR (MvfR) is a key comp ...

    Bacterial populations co-ordinate gene expression collectively through quorum sensing (QS), a cell-to-cell communication mechanism employing diffusible signal molecules. The LysR-type transcriptional regulator (LTTR) protein PqsR (MvfR) is a key component of alkyl-quinolone (AQ)-dependent QS in Pseudomonas aeruginosa. PqsR is activated by 2-alkyl-4-quinolones including the Pseudomonas quinolone signal (PQS; 2-heptyl-3-hydroxy-4(1H)-quinolone), its precursor 2-heptyl-4-hydroxyquinoline (HHQ) and their C9 congeners, 2-nonyl-3-hydroxy-4(1H)-quinolone (C9-PQS) and 2-nonyl-4-hydroxyquinoline (NHQ). These drive the autoinduction of AQ biosynthesis and the up-regulation of key virulence determinants as a function of bacterial population density. Consequently, PqsR constitutes a potential target for novel antibacterial agents which attenuate infection through the blockade of virulence. Here we present the crystal structures of the PqsR co-inducer binding domain (CBD) and a complex with the native agonist NHQ. We show that the structure of the PqsR CBD has an unusually large ligand-binding pocket in which a native AQ agonist is stabilized entirely by hydrophobic interactions. Through a ligand-based design strategy we synthesized and evaluated a series of 50 AQ and novel quinazolinone (QZN) analogues and measured the impact on AQ biosynthesis, virulence gene expression and biofilm development. The simple exchange of two isosteres (OH for NHâ‚‚) switches a QZN agonist to an antagonist with a concomitant impact on the induction of bacterial virulence factor production. We also determined the complex crystal structure of a QZN antagonist bound to PqsR revealing a similar orientation in the ligand binding pocket to the native agonist NHQ. This structure represents the first description of an LTTR-antagonist complex. Overall these studies present novel insights into LTTR ligand binding and ligand-based drug design and provide a chemical scaffold for further anti-P. aeruginosa virulence drug development by targeting the AQ receptor PqsR.


    Organizational Affiliation

    Centre for Biomolecular Sciences, University of Nottingham, University Park, Nottingham, United Kingdom.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Transcriptional regulator MvfR
A
216Pseudomonas aeruginosa (strain UCBPP-PA14)Mutation(s): 0 
Gene Names: mvfR
Find proteins for A0A0H2Z7A6 (Pseudomonas aeruginosa (strain UCBPP-PA14))
Go to UniProtKB:  A0A0H2Z7A6
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MRD
Query on MRD

Download SDF File 
Download CCD File 
A
(4R)-2-METHYLPENTANE-2,4-DIOL
C6 H14 O2
SVTBMSDMJJWYQN-RXMQYKEDSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.5 Å
  • R-Value Free: 0.267 
  • R-Value Work: 0.222 
  • Space Group: P 65 2 2
Unit Cell:
Length (Å)Angle (°)
a = 119.733α = 90.00
b = 119.733β = 90.00
c = 115.777γ = 120.00
Software Package:
Software NamePurpose
SCALAdata scaling
REFMACrefinement
XDSdata reduction
SOLVEphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2013-08-07
    Type: Initial release
  • Version 1.1: 2014-02-12
    Type: Database references