1QVT

CRYSTAL STRUCTURE OF THE MULTIDRUG BINDING TRANSCRIPTIONAL REPRESSOR QACR BOUND TO THE DRUG PROFLAVINE


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.89 Å
  • R-Value Free: 0.291 
  • R-Value Work: 0.232 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural mechanism of the simultaneous binding of two drugs to a multidrug-binding protein

Schumacher, M.A.Miller, M.C.Brennan, R.G.

(2004) Embo J. 23: 2923-2930

  • DOI: 10.1038/sj.emboj.7600288
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The structural basis of simultaneous binding of two or more different drugs by any multidrug-binding protein is unknown and also how this can lead to a noncompetitive, uncompetitive or cooperative binding mechanism. Here, we describe the crystal stru ...

    The structural basis of simultaneous binding of two or more different drugs by any multidrug-binding protein is unknown and also how this can lead to a noncompetitive, uncompetitive or cooperative binding mechanism. Here, we describe the crystal structure of the Staphylococcus aureus multidrug-binding transcription repressor, QacR, bound simultaneously to ethidium (Et) and proflavin (Pf). The structure underscores the plasticity of the multidrug-binding pocket and reveals an alternative, Pf-induced binding mode for Et. To monitor the simultaneous binding of Pf and Et to QacR, as well as to determine the effects on the binding affinity of one drug when the other drug is prebound, a novel application of near-ultraviolet circular dichroism (UVCD) was developed. The UVCD equilibrium-binding studies revealed identical affinities of Pf for QacR in the presence or absence of Et, but significantly diminished affinity of Et for QacR when Pf is prebound, findings that are readily explicable by their structures. The principles for simultaneous binding of two different drugs discerned here are likely employed by the multidrug efflux transporters.


    Organizational Affiliation

    Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, OR 97201-3098, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Transcriptional regulator qacR
B, D, A, E
194Staphylococcus aureusMutation(s): 0 
Gene Names: qacR
Find proteins for P0A0N4 (Staphylococcus aureus)
Go to UniProtKB:  P0A0N4
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download SDF File 
Download CCD File 
A, B, D, E
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
PRL
Query on PRL

Download SDF File 
Download CCD File 
A
PROFLAVIN
C13 H11 N3
WDVSHHCDHLJJJR-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.89 Å
  • R-Value Free: 0.291 
  • R-Value Work: 0.232 
  • Space Group: P 42 21 2
Unit Cell:
Length (Å)Angle (°)
a = 172.300α = 90.00
b = 172.300β = 90.00
c = 94.750γ = 90.00
Software Package:
Software NamePurpose
CCP4data scaling
MOSFLMdata reduction
CNSphasing
CNSrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2004-08-03
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance