1EK9

2.1A X-RAY STRUCTURE OF TOLC: AN INTEGRAL OUTER MEMBRANE PROTEIN AND EFFLUX PUMP COMPONENT FROM ESCHERICHIA COLI


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.257 
  • R-Value Work: 0.208 
  • R-Value Observed: 0.208 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Crystal structure of the bacterial membrane protein TolC central to multidrug efflux and protein export.

Koronakis, V.Sharff, A.Koronakis, E.Luisi, B.Hughes, C.

(2000) Nature 405: 914-919

  • DOI: 10.1038/35016007
  • Primary Citation of Related Structures:  
    1EK9

  • PubMed Abstract: 
  • Diverse molecules, from small antibacterial drugs to large protein toxins, are exported directly across both cell membranes of gram-negative bacteria. This export is brought about by the reversible interaction of substrate-specific inner-membrane proteins with an outer-membrane protein of the TolC family, thus bypassing the intervening periplasm ...

    Diverse molecules, from small antibacterial drugs to large protein toxins, are exported directly across both cell membranes of gram-negative bacteria. This export is brought about by the reversible interaction of substrate-specific inner-membrane proteins with an outer-membrane protein of the TolC family, thus bypassing the intervening periplasm. Here we report the 2.1-A crystal structure of TolC from Escherichia coli, revealing a distinctive and previously unknown fold. Three TolC protomers assemble to form a continuous, solvent-accessible conduit--a 'channel-tunnel' over 140 A long that spans both the outer membrane and periplasmic space. The periplasmic or proximal end of the tunnel is sealed by sets of coiled helices. We suggest these could be untwisted by an allosteric mechanism, mediated by protein-protein interactions, to open the tunnel. The structure provides an explanation of how the cell cytosol is connected to the external environment during export, and suggests a general mechanism for the action of bacterial efflux pumps.


    Related Citations: 
    • Oxidation of Selenomethionine: Some MADness in the Method!
      Sharff, A.J., Koronakis, E., Luisi, B., Koronakis, V.
      (2000) Acta Crystallogr D Biol Crystallogr 56: 785

    Organizational Affiliation

    Department of Pathology, University of Cambridge, UK.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
OUTER MEMBRANE PROTEIN TOLCA, B, C428Escherichia coliMutation(s): 5 
Membrane Entity: Yes 
UniProt
Find proteins for P02930 (Escherichia coli (strain K12))
Explore P02930 
Go to UniProtKB:  P02930
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
MSE
Query on MSE
A, B, CL-PEPTIDE LINKINGC5 H11 N O2 SeMET
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.10 Å
  • R-Value Free: 0.257 
  • R-Value Work: 0.208 
  • R-Value Observed: 0.208 
  • Space Group: H 3
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 265.049α = 90
b = 265.049β = 90
c = 95.959γ = 120
Software Package:
Software NamePurpose
SHARPphasing
BUSTER-TNTrefinement
DENZOdata reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report




Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2000-06-28
    Type: Initial release
  • Version 1.1: 2008-04-27
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance