5ENS

Rhodamine bound structure of bacterial efflux pump.


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.258 
  • R-Value Work: 0.194 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Molecular basis for inhibition of AcrB multidrug efflux pump by novel and powerful pyranopyridine derivatives.

Sjuts, H.Vargiu, A.V.Kwasny, S.M.Nguyen, S.T.Kim, H.S.Ding, X.Ornik, A.R.Ruggerone, P.Bowlin, T.L.Nikaido, H.Pos, K.M.Opperman, T.J.

(2016) Proc.Natl.Acad.Sci.USA 113: 3509-3514

  • DOI: 10.1073/pnas.1602472113
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The Escherichia coli AcrAB-TolC efflux pump is the archetype of the resistance nodulation cell division (RND) exporters from Gram-negative bacteria. Overexpression of RND-type efflux pumps is a major factor in multidrug resistance (MDR), which makes ...

    The Escherichia coli AcrAB-TolC efflux pump is the archetype of the resistance nodulation cell division (RND) exporters from Gram-negative bacteria. Overexpression of RND-type efflux pumps is a major factor in multidrug resistance (MDR), which makes these pumps important antibacterial drug discovery targets. We have recently developed novel pyranopyridine-based inhibitors of AcrB, which are orders of magnitude more powerful than the previously known inhibitors. However, further development of such inhibitors has been hindered by the lack of structural information for rational drug design. Although only the soluble, periplasmic part of AcrB binds and exports the ligands, the presence of the membrane-embedded domain in AcrB and its polyspecific binding behavior have made cocrystallization with drugs challenging. To overcome this obstacle, we have engineered and produced a soluble version of AcrB [AcrB periplasmic domain (AcrBper)], which is highly congruent in structure with the periplasmic part of the full-length protein, and is capable of binding substrates and potent inhibitors. Here, we describe the molecular basis for pyranopyridine-based inhibition of AcrB using a combination of cellular, X-ray crystallographic, and molecular dynamics (MD) simulations studies. The pyranopyridines bind within a phenylalanine-rich cage that branches from the deep binding pocket of AcrB, where they form extensive hydrophobic interactions. Moreover, the increasing potency of improved inhibitors correlates with the formation of a delicate protein- and water-mediated hydrogen bond network. These detailed insights provide a molecular platform for the development of novel combinational therapies using efflux pump inhibitors for combating multidrug resistant Gram-negative pathogens.


    Organizational Affiliation

    Institute of Biochemistry, Goethe University Frankfurt, D-60438 Frankfurt, Germany;




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Multidrug efflux pump subunit AcrB,Multidrug efflux pump subunit AcrB
A, B, C
609Escherichia coli (strain K12)Mutation(s): 0 
Gene Names: acrB (acrE)
Find proteins for P31224 (Escherichia coli (strain K12))
Go to UniProtKB:  P31224
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
DARPin
D, E, F
169N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
RHQ
Query on RHQ

Download SDF File 
Download CCD File 
C
RHODAMINE 6G
C28 H31 N2 O3
IWWWBRIIGAXLCJ-KRUMMXJUSA-O
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.8 Å
  • R-Value Free: 0.258 
  • R-Value Work: 0.194 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 108.652α = 90.00
b = 145.245β = 90.00
c = 174.148γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
XDSdata scaling
PHASERphasing
XDSdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2016-04-06
    Type: Initial release
  • Version 1.1: 2016-04-13
    Type: Database references