1AN8

CRYSTAL STRUCTURE OF THE STREPTOCOCCAL SUPERANTIGEN SPE-C


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.40 Å
  • R-Value Free: 0.210 
  • R-Value Work: 0.171 
  • R-Value Observed: 0.174 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Crystal structure of the streptococcal superantigen SPE-C: dimerization and zinc binding suggest a novel mode of interaction with MHC class II molecules.

Roussel, A.Anderson, B.F.Baker, H.M.Fraser, J.D.Baker, E.N.

(1997) Nat Struct Biol 4: 635-643

  • DOI: https://doi.org/10.1038/nsb0897-635
  • Primary Citation of Related Structures:  
    1AN8

  • PubMed Abstract: 

    Bacterial superantigens are small proteins that have a very potent stimulatory effect on T lymphocytes through their ability to bind to both MHC class II molecules and T-cell receptors. We have determined the three-dimensional structure of a Streptococcal superantigen, SPE-C, at 2.4 A resolution. The structure shows that SPE-C has the usual superantigen fold, but that the surface that forms a generic, low-affinity MHC-binding site in other superantigens is here used to create a SPE-C dimer. Instead, MHC class II binding occurs through a zinc binding site that is analogous to a similar site in staphylococcal enterotoxin A. Consideration of the SPE-C dimer suggests a novel mechanism for promotion of MHC aggregation and T-cell activation.


  • Organizational Affiliation

    Department of Biochemistry, Massey University, Palmerston North, New Zealand.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
STREPTOCOCCAL PYROGENIC EXOTOXIN C208Streptococcus pyogenesMutation(s): 0 
UniProt
Find proteins for Q8NKX2 (Streptococcus pyogenes serotype M18 (strain MGAS8232))
Explore Q8NKX2 
Go to UniProtKB:  Q8NKX2
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ8NKX2
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.40 Å
  • R-Value Free: 0.210 
  • R-Value Work: 0.171 
  • R-Value Observed: 0.174 
  • Space Group: P 43 21 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 75.41α = 90
b = 75.41β = 90
c = 168.87γ = 90
Software Package:
Software NamePurpose
CCP4model building
TNTrefinement
DENZOdata reduction
CCP4data scaling
CCP4phasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 1998-04-29
    Type: Initial release
  • Version 1.1: 2008-03-24
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2024-02-07
    Changes: Data collection, Database references, Other