5MKK

Crystal structure of the heterodimeric ABC transporter TmrAB, a homolog of the antigen translocation complex TAP


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.70 Å
  • R-Value Free: 0.272 
  • R-Value Work: 0.226 
  • R-Value Observed: 0.228 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Crystal structure and mechanistic basis of a functional homolog of the antigen transporter TAP.

Noll, A.Thomas, C.Herbring, V.Zollmann, T.Barth, K.Mehdipour, A.R.Tomasiak, T.M.Bruchert, S.Joseph, B.Abele, R.Olieric, V.Wang, M.Diederichs, K.Hummer, G.Stroud, R.M.Pos, K.M.Tampe, R.

(2017) Proc Natl Acad Sci U S A 114: E438-E447

  • DOI: 10.1073/pnas.1620009114
  • Primary Citation of Related Structures:  
    5MKK

  • PubMed Abstract: 
  • ABC transporters form one of the largest protein superfamilies in all domains of life, catalyzing the movement of diverse substrates across membranes. In this key position, ABC transporters can mediate multidrug resistance in cancer therapy and their dys ...

    ABC transporters form one of the largest protein superfamilies in all domains of life, catalyzing the movement of diverse substrates across membranes. In this key position, ABC transporters can mediate multidrug resistance in cancer therapy and their dysfunction is linked to various diseases. Here, we describe the 2.7-Å X-ray structure of heterodimeric Thermus thermophilus multidrug resistance proteins A and B (TmrAB), which not only shares structural homology with the antigen translocation complex TAP, but is also able to restore antigen processing in human TAP-deficient cells. TmrAB exhibits a broad peptide specificity and can concentrate substrates several thousandfold, using only one single active ATP-binding site. In our structure, TmrAB adopts an asymmetric inward-facing state, and we show that the C-terminal helices, arranged in a zipper-like fashion, play a crucial role in guiding the conformational changes associated with substrate transport. In conclusion, TmrAB can be regarded as a model system for asymmetric ABC exporters in general, and for TAP in particular.


    Organizational Affiliation

    Institute of Biochemistry, Biocenter, Goethe University Frankfurt, 60438 Frankfurt am Main, Germany; stroud@msg.ucsf.edu tampe@em.uni-frankfurt.de.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Multidrug resistance ABC transporter ATP-binding and permease protein A611Thermus thermophilus HB27Mutation(s): 0 
Gene Names: TT_C0976
Membrane protein
Mpstruc
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
ATP Binding Cassette (ABC) Transporters
Protein: 
TmrAB antigen transporter homolog
Find proteins for Q72J05 (Thermus thermophilus (strain HB27 / ATCC BAA-163 / DSM 7039))
Explore Q72J05 
Go to UniProtKB:  Q72J05
Protein Feature View
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
Multidrug resistance ABC transporter ATP-binding and permease protein B577Thermus thermophilus HB27Mutation(s): 0 
Gene Names: TT_C0977
Membrane protein
Mpstruc
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
ATP Binding Cassette (ABC) Transporters
Protein: 
TmrAB antigen transporter homolog
Find proteins for Q72J04 (Thermus thermophilus (strain HB27 / ATCC BAA-163 / DSM 7039))
Explore Q72J04 
Go to UniProtKB:  Q72J04
Protein Feature View
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download Ideal Coordinates CCD File 
A, B
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.70 Å
  • R-Value Free: 0.272 
  • R-Value Work: 0.226 
  • R-Value Observed: 0.228 
  • Space Group: P 65 2 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 93.371α = 90
b = 93.371β = 90
c = 1043.95γ = 120
Software Package:
Software NamePurpose
PHENIXrefinement
XDSdata reduction
XDSdata scaling
SHELXDEphasing

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
German Research FoundationGermanySFB 807
German Research FoundationGermanyEXC 115
National Institutes of HealthUnited StatesGM111126
National Institutes of HealthUnited StatesGM114245

Revision History 

  • Version 1.0: 2017-01-18
    Type: Initial release
  • Version 1.1: 2017-02-08
    Changes: Database references
  • Version 1.2: 2018-01-31
    Changes: Author supporting evidence