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 
  • R-Value Observed: 0.232 

wwPDB Validation   3D Report Full Report


This is version 1.3 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:  
    1QVU, 1QVT

  • 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: 
(by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Transcriptional regulator qacRA, B, D, E194Staphylococcus aureusMutation(s): 0 
Gene Names: QACR OR SAVP031, qacR, SAP100B_005, SAP104C_022
Find proteins for P0A0N4 (Staphylococcus aureus)
Explore P0A0N4 
Go to UniProtKB:  P0A0N4
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PRL
Query on PRL
Download CCD File 
A
PROFLAVIN
C13 H11 N3
WDVSHHCDHLJJJR-UHFFFAOYSA-N		 Ligand Interaction
SO4
Query on SO4
Download CCD File 
A, B, D, E
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L		 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 
  • R-Value Observed: 0.232 
  • Space Group: P 42 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 172.3α = 90
b = 172.3β = 90
c = 94.75γ = 90
Software Package:
Software NamePurpose
CNSrefinement
MOSFLMdata reduction
CCP4data scaling
CNSphasing

Structure Validation

View Full Validation Report


View more in-depth experimental data

Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2004-08-03
    Type: Initial release
  • Version 1.1: 2008-04-29
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2020-02-26
    Changes: Advisory, Data collection, Database references, Derived calculations