2NTT

Crystal Structure of SEK


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.561 Å
  • R-Value Free: 0.202 
  • R-Value Work: 0.163 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

A novel loop domain in superantigens extends their T cell receptor recognition site

Gunther, S.Varma, A.K.Moza, B.Kasper, K.J.Wyatt, A.W.Zhu, P.Rahman, A.K.Li, Y.Mariuzza, R.A.McCormick, J.K.Sundberg, E.J.

(2007) J.Mol.Biol. 371: 210-221

  • DOI: 10.1016/j.jmb.2007.05.038
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Superantigens (SAGs) interact with host immune receptors to induce a massive release of inflammatory cytokines that can lead to toxic shock syndrome and death. Bacterial SAGs can be classified into five distinct evolutionary groups. Group V SAGs are ...

    Superantigens (SAGs) interact with host immune receptors to induce a massive release of inflammatory cytokines that can lead to toxic shock syndrome and death. Bacterial SAGs can be classified into five distinct evolutionary groups. Group V SAGs are characterized by the alpha3-beta8 loop, a unique approximately 15 amino acid residue extension that is required for optimal T cell activation. Here, we report the X-ray crystal structures of the group V SAG staphylococcal enterotoxin K (SEK) alone and in complex with the TCR hVbeta5.1 domain. SEK adopts a unique TCR binding orientation relative to other SAG-TCR complexes, which results in the alpha3-beta8 loop contacting the apical loop of framework region 4, thereby extending the known TCR recognition site of SAGs. These interactions are absolutely required for TCR binding and T cell activation by SEK, and dictate the TCR Vbeta domain specificity of SEK and other group V SAGs.


    Organizational Affiliation

    Boston Biomedical Research Institute, Watertown, MA 02472, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Staphylococcal enterotoxin K
A, B
217Staphylococcus aureusMutation(s): 0 
Gene Names: sek
Find proteins for Q93CC5 (Staphylococcus aureus)
Go to UniProtKB:  Q93CC5
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CL
Query on CL

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

Download SDF File 
Download CCD File 
A, B
1,2-ETHANEDIOL
ETHYLENE GLYCOL
C2 H6 O2
LYCAIKOWRPUZTN-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.561 Å
  • R-Value Free: 0.202 
  • R-Value Work: 0.163 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 53.774α = 90.00
b = 45.790β = 90.02
c = 90.696γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
HKL-2000data scaling
AMoREphasing
HKL-2000data collection
HKL-2000data reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2007-06-26
    Type: Initial release
  • Version 1.1: 2008-05-01
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Source and taxonomy, Version format compliance