4LQD

The crystal structures of the Brucella protein TcpB and the TLR adaptor protein TIRAP show structural differences in microbial TIR mimicry


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.45 Å
  • R-Value Free: 0.218 
  • R-Value Work: 0.207 
  • R-Value Observed: 0.208 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Crystal structures of the Toll/Interleukin-1 receptor (TIR) domains from the Brucella protein TcpB and host adaptor TIRAP reveal mechanisms of molecular mimicry.

Snyder, G.A.Deredge, D.Waldhuber, A.Fresquez, T.Wilkins, D.Z.Smith, P.T.Durr, S.Cirl, C.Jiang, J.Jennings, W.Luchetti, T.Snyder, N.Sundberg, E.J.Wintrode, P.Miethke, T.Xiao, T.S.

(2014) J Biol Chem 289: 669-679

  • DOI: 10.1074/jbc.M113.523407
  • Primary Citation of Related Structures:  
    4LQC, 4LQD

  • PubMed Abstract: 
  • The Toll/IL-1 receptor (TIR) domains are crucial innate immune signaling modules. Microbial TIR domain-containing proteins inhibit Toll-like receptor (TLR) signaling through molecular mimicry. The TIR domain-containing protein TcpB from Brucella inhibits TLR signaling through interaction with host adaptor proteins TIRAP/Mal and MyD88 ...

    The Toll/IL-1 receptor (TIR) domains are crucial innate immune signaling modules. Microbial TIR domain-containing proteins inhibit Toll-like receptor (TLR) signaling through molecular mimicry. The TIR domain-containing protein TcpB from Brucella inhibits TLR signaling through interaction with host adaptor proteins TIRAP/Mal and MyD88. To characterize the microbial mimicry of host proteins, we have determined the X-ray crystal structures of the TIR domains from the Brucella protein TcpB and the host adaptor protein TIRAP. We have further characterized homotypic interactions of TcpB using hydrogen/deuterium exchange mass spectrometry and heterotypic TcpB and TIRAP interaction by co-immunoprecipitation and NF-κB reporter assays. The crystal structure of the TcpB TIR domain reveals the microtubule-binding site encompassing the BB loop as well as a symmetrical dimer mediated by the DD and EE loops. This dimerization interface is validated by peptide mapping through hydrogen/deuterium exchange mass spectrometry. The human TIRAP TIR domain crystal structure reveals a unique N-terminal TIR domain fold containing a disulfide bond formed by Cys(89) and Cys(134). A comparison between the TcpB and TIRAP crystal structures reveals substantial conformational differences in the region that encompasses the BB loop. These findings underscore the similarities and differences in the molecular features found in the microbial and host TIR domains, which suggests mechanisms of bacterial mimicry of host signaling adaptor proteins, such as TIRAP.


    Organizational Affiliation

    From the Laboratory of Immunology, NIAID, National Institutes of Health, Bethesda, Maryland 20892.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Toll/interleukin-1 receptor domain-containing adapter proteinA144Homo sapiensMutation(s): 0 
Gene Names: TIRAPMAL
Find proteins for P58753 (Homo sapiens)
Explore P58753 
Go to UniProtKB:  P58753
NIH Common Fund Data Resources
PHAROS  P58753
Protein Feature View
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  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
GOL
Query on GOL

Download CCD File 
A
GLYCEROL
C3 H8 O3
PEDCQBHIVMGVHV-UHFFFAOYSA-N
 Ligand Interaction
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
CME
Query on CME
AL-PEPTIDE LINKINGC5 H11 N O3 S2CYS
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.45 Å
  • R-Value Free: 0.218 
  • R-Value Work: 0.207 
  • R-Value Observed: 0.208 
  • Space Group: P 43 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 87.57α = 90
b = 87.57β = 90
c = 80.65γ = 90
Software Package:
Software NamePurpose
HKL-2000data collection
SHELXSphasing
PHENIXrefinement
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2013-12-04
    Type: Initial release
  • Version 1.1: 2014-04-09
    Changes: Database references