5NIK

Structure of the MacAB-TolC ABC-type tripartite multidrug efflux pump


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.3 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation 3D Report Full Report


This is version 1.0 of the entry. See complete history

Literature

Structure of the MacAB-TolC ABC-type tripartite multidrug efflux pump.

Fitzpatrick, A.W.P.Llabres, S.Neuberger, A.Blaza, J.N.Bai, X.C.Okada, U.Murakami, S.van Veen, H.W.Zachariae, U.Scheres, S.H.W.Luisi, B.F.Du, D.

(2017) Nat Microbiol 2: 17070-17070

  • DOI: 10.1038/nmicrobiol.2017.70
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The MacA-MacB-TolC assembly of Escherichia coli is a transmembrane machine that spans the cell envelope and actively extrudes substrates, including macrolide antibiotics and polypeptide virulence factors. These transport processes are energized by th ...

    The MacA-MacB-TolC assembly of Escherichia coli is a transmembrane machine that spans the cell envelope and actively extrudes substrates, including macrolide antibiotics and polypeptide virulence factors. These transport processes are energized by the ATPase MacB, a member of the ATP-binding cassette (ABC) superfamily. We present an electron cryo-microscopy structure of the ABC-type tripartite assembly at near-atomic resolution. A hexamer of the periplasmic protein MacA bridges between a TolC trimer in the outer membrane and a MacB dimer in the inner membrane, generating a quaternary structure with a central channel for substrate translocation. A gating ring found in MacA is proposed to act as a one-way valve in substrate transport. The MacB structure features an atypical transmembrane domain with a closely packed dimer interface and a periplasmic opening that is the likely portal for substrate entry from the periplasm, with subsequent displacement through an allosteric transport mechanism.


    Organizational Affiliation

    Medical Research Council Laboratory of Molecular Biology, Cambridge Biomedical Campus, Francis Crick Avenue, Cambridge CB2 0QH, U.K.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Outer membrane protein TolC
A, B, C
479Escherichia coli (strain K12)Mutation(s): 0 
Gene Names: tolC (colE1-i, mtcB, mukA, refI, toc, weeA)
Membrane protein
mpstruc
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
ATP Binding Cassette (ABC) Transporters
Protein: 
MacAB-TolC tripartite multidrug efflux pump, MacA-TolC section
Find proteins for P02930 (Escherichia coli (strain K12))
Go to UniProtKB:  P02930
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Macrolide export protein MacA
D, E, F, G, H, I
371Escherichia coli (strain K12)Mutation(s): 0 
Gene Names: macA (ybjY)
Membrane protein
mpstruc
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
ATP Binding Cassette (ABC) Transporters
Protein: 
MacAB-TolC tripartite multidrug efflux pump, MacA-TolC section
Find proteins for P75830 (Escherichia coli (strain K12))
Go to UniProtKB:  P75830
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
Macrolide export ATP-binding/permease protein MacB
J, K
654Escherichia coli (strain K12)Mutation(s): 0 
Gene Names: macB (ybjZ)
EC: 3.6.3.-
Membrane protein
mpstruc
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
ATP Binding Cassette (ABC) Transporters
Protein: 
MacAB-TolC tripartite multidrug efflux pump, MacA-TolC section
Find proteins for P75831 (Escherichia coli (strain K12))
Go to UniProtKB:  P75831
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.3 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Wellcome TrustUnited KingdomRG61065
Human Frontier Science ProgramJapanRG68784

Revision History 

  • Version 1.0: 2017-05-24
    Type: Initial release