5D3I

Crystal structure of the SSL3-TLR2 complex


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.2 Å
  • R-Value Free: 0.271 
  • R-Value Work: 0.231 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structural basis for inhibition of TLR2 by staphylococcal superantigen-like protein 3 (SSL3).

Koymans, K.J.Feitsma, L.J.Brondijk, T.H.Aerts, P.C.Lukkien, E.Lossl, P.van Kessel, K.P.de Haas, C.J.van Strijp, J.A.Huizinga, E.G.

(2015) Proc.Natl.Acad.Sci.USA 112: 11018-11023

  • DOI: 10.1073/pnas.1502026112
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Toll-like receptors (TLRs) are crucial in innate recognition of invading micro-organisms and their subsequent clearance. Bacteria are not passive bystanders and have evolved complex evasion mechanisms. Staphylococcus aureus secretes a potent TLR2 ant ...

    Toll-like receptors (TLRs) are crucial in innate recognition of invading micro-organisms and their subsequent clearance. Bacteria are not passive bystanders and have evolved complex evasion mechanisms. Staphylococcus aureus secretes a potent TLR2 antagonist, staphylococcal superantigen-like protein 3 (SSL3), which prevents receptor stimulation by pathogen-associated lipopeptides. Here, we present crystal structures of SSL3 and its complex with TLR2. The structure reveals that formation of the specific inhibitory complex is predominantly mediated by hydrophobic contacts between SSL3 and TLR2 and does not involve interaction of TLR2-glycans with the conserved Lewis(X) binding site of SSL3. In the complex, SSL3 partially covers the entrance to the lipopeptide binding pocket in TLR2, reducing its size by ∼50%. We show that this is sufficient to inhibit binding of agonist Pam2CSK4 effectively, yet allows SSL3 to bind to an already formed TLR2-Pam2CSK4 complex. The binding site of SSL3 overlaps those of TLR2 dimerization partners TLR1 and TLR6 extensively. Combined, our data reveal a robust dual mechanism in which SSL3 interferes with TLR2 activation at two stages: by binding to TLR2, it blocks ligand binding and thus inhibits activation. Second, by interacting with an already formed TLR2-lipopeptide complex, it prevents TLR heterodimerization and downstream signaling.


    Organizational Affiliation

    Department of Medical Microbiology, University Medical Center Utrecht, NL-3584 CX, Utrecht, The Netherlands;




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Toll-like receptor 2
A
568Mus musculusMutation(s): 0 
Gene Names: Tlr2
Find proteins for Q9QUN7 (Mus musculus)
Go to UniProtKB:  Q9QUN7
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Staphylococcal Superantigen-Like protein 3
B
195Staphylococcus aureus (strain NCTC 8325)Mutation(s): 0 
Gene Names: ssl3
Find proteins for Q2G0X7 (Staphylococcus aureus (strain NCTC 8325))
Go to UniProtKB:  Q2G0X7
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CL
Query on CL

Download SDF File 
Download CCD File 
A
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
NAG
Query on NAG

Download SDF File 
Download CCD File 
A
N-ACETYL-D-GLUCOSAMINE
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
PCW
Query on PCW

Download SDF File 
Download CCD File 
A
1,2-DIOLEOYL-SN-GLYCERO-3-PHOSPHOCHOLINE
(Z,Z)-4-HYDROXY-N,N,N-TRIMETHYL-10-OXO-7-[(1-OXO-9-OCTADECENYL)OXY]-3,5,9-TRIOXA-4-PHOSPHAHEPTACOS-18-EN-1-AMINIUM-4-OXIDE
C44 H85 N O8 P
SNKAWJBJQDLSFF-NVKMUCNASA-O
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.2 Å
  • R-Value Free: 0.271 
  • R-Value Work: 0.231 
  • Space Group: P 61
Unit Cell:
Length (Å)Angle (°)
a = 104.198α = 90.00
b = 104.198β = 90.00
c = 153.625γ = 120.00
Software Package:
Software NamePurpose
XDSdata reduction
PHENIXrefinement
Aimlessdata scaling
PHASERphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Netherlands Organization for Scientific ResearchNetherlandsECHO Grant 700.58.006
Netherlands Organization for Health Research and DevelopmentNetherlandsZonMw Grant 205200004
Dutch Top Institute Pharma ProjectNetherlandsD1-101

Revision History 

  • Version 1.0: 2015-08-19
    Type: Initial release
  • Version 1.1: 2015-09-02
    Type: Database references
  • Version 1.2: 2015-09-09
    Type: Database references