3NE5

Crystal structure of the CusBA heavy-metal efflux complex from Escherichia coli


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.898 Å
  • R-Value Free: 0.267 
  • R-Value Work: 0.229 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Crystal structure of the CusBA heavy-metal efflux complex of Escherichia coli.

Su, C.C.Long, F.Zimmermann, M.T.Rajashankar, K.R.Jernigan, R.L.Yu, E.W.

(2011) Nature 470: 558-562

  • DOI: 10.1038/nature09743

  • PubMed Abstract: 
  • Gram-negative bacteria, such as Escherichia coli, expel toxic chemicals through tripartite efflux pumps that span both the inner and outer membrane. The three parts are an inner membrane, substrate-binding transporter; a membrane fusion protein; and ...

    Gram-negative bacteria, such as Escherichia coli, expel toxic chemicals through tripartite efflux pumps that span both the inner and outer membrane. The three parts are an inner membrane, substrate-binding transporter; a membrane fusion protein; and an outer-membrane-anchored channel. The fusion protein connects the transporter to the channel within the periplasmic space. A crystallographic model of this tripartite efflux complex has been unavailable because co-crystallization of the various components of the system has proven to be extremely difficult. We previously described the crystal structures of both the inner membrane transporter CusA and the membrane fusion protein CusB of the CusCBA efflux system of E. coli. Here we report the co-crystal structure of the CusBA efflux complex, showing that the transporter (or pump) CusA, which is present as a trimer, interacts with six CusB protomers and that the periplasmic domain of CusA is involved in these interactions. The six CusB molecules seem to form a continuous channel. The affinity of the CusA and CusB interaction was found to be in the micromolar range. Finally, we have predicted a three-dimensional structure for the trimeric CusC outer membrane channel and developed a model of the tripartite efflux assemblage. This CusC(3)-CusB(6)-CusA(3) model shows a 750-kilodalton efflux complex that spans the entire bacterial cell envelope and exports Cu I and Ag I ions.


    Organizational Affiliation

    Department of Chemistry, Iowa State University, Ames, Iowa 50011, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Cation efflux system protein cusB
B, C
413Escherichia coli (strain K12)Gene Names: cusB (ylcD)
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Multi-Drug Efflux Transporters
Protein: 
CusA metal-ion efflux pump
Find proteins for P77239 (Escherichia coli (strain K12))
Go to UniProtKB:  P77239
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Cation efflux system protein cusA
A
1054Escherichia coli (strain K12)Gene Names: cusA (ybdE)
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Multi-Drug Efflux Transporters
Protein: 
CusA metal-ion efflux pump
Find proteins for P38054 (Escherichia coli (strain K12))
Go to UniProtKB:  P38054
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.898 Å
  • R-Value Free: 0.267 
  • R-Value Work: 0.229 
  • Space Group: H 3 2
Unit Cell:
Length (Å)Angle (°)
a = 160.267α = 90.00
b = 160.267β = 90.00
c = 682.835γ = 120.00
Software Package:
Software NamePurpose
SCALEPACKdata scaling
PHASERphasing
PDB_EXTRACTdata extraction
DENZOdata reduction
PHENIXrefinement
ADSCdata collection
HKL-2000data scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2010-06-08 
  • Released Date: 2011-03-02 
  • Deposition Author(s): Su, C.-C.

Revision History 

  • Version 1.0: 2011-03-02
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance
  • Version 1.2: 2013-09-18
    Type: Derived calculations
  • Version 1.3: 2017-11-08
    Type: Refinement description