Biological Assembly 1  

 3D View: Structure | Electron Density

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Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 6-mer - A4BC 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 152460.28 
• Atom Count: 9511 
• Residue Count: 1326 
• Unique protein chains: 2

1KTK

Complex of Streptococcal pyrogenic enterotoxin C (SpeC) with a human T cell receptor beta chain (Vbeta2.1)

• DOI: 10.2210/pdb1KTK/pdb

• Classification: IMMUNE SYSTEM
• Organism(s): Streptococcus pyogenes serotype M18 (strain MGAS8232), Homo sapiens
• Expression System: Escherichia coli


• Deposited: 2002-01-16 Released: 2002-06-07 
• Deposition Author(s): Sundberg, E.J., Li, H., Llera, A.S., McCormick, J.K., Tormo, J., Karjalainen, K., Schlievert, P.M., Mariuzza, R.A.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3 Å
• R-Value Free: 0.334 
• R-Value Work: 0.326 

Literature

Structures of two streptococcal superantigens bound to TCR beta chains reveal diversity in the architecture of T cell signaling complexes.

Sundberg, E.J., Li, H., Llera, A.S., McCormick, J.K., Tormo, J., Schlievert, P.M., Karjalainen, K., Mariuzza, R.A.

(2002) Structure 10: 687-699

• PubMed: 12015151 
• Primary Citation of Related Structures:  
  1L0Y, 1L0X


• PubMed Abstract: 
  

Superantigens (SAGs) crosslink MHC class II and TCR molecules, resulting in an overstimulation of T cells associated with human disease. SAGs interact with several different surfaces on MHC molecules, necessitating the formation of multiple distinct MHC-SAG-TCR ternary signaling complexes. Variability in SAG-TCR binding modes could also contribute to the structural heterogeneity of SAG-dependent signaling complexes. We report crystal structures of the streptococcal SAGs SpeA and SpeC in complex with their corresponding TCR beta chain ligands that reveal distinct TCR binding modes. The SpeC-TCR beta chain complex structure, coupled with the recently determined SpeC-HLA-DR2a complex structure, provides a model for a novel T cell signaling complex that precludes direct TCR-MHC interactions. Thus, highly efficient T cell activation may be achieved through structurally diverse strategies of TCR ligation.

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Organizational Affiliation: 

Center for Advanced Research in Biotechnology, W.M. Keck Laboratory for Structural Biology, University of Maryland Biotechnology Institute, 9600 Gudelsky Drive, Rockville, MD 20850, USA.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
Exotoxin type C	A, B, C, D	208	Streptococcus pyogenes serotype M18 (strain MGAS8232)	Mutation(s): 0  Gene Names: speC
Find proteins for Q8NKX2 (Streptococcus pyogenes serotype M18 (strain MGAS8232)) Go to UniProtKB:  Q8NKX2

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details
T-cell receptor beta chain	E, F	247	Homo sapiens	Mutation(s): 0  Gene Names: TRBC1
Find proteins for P01850 (Homo sapiens) Go to UniProtKB:  P01850

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3 Å
• R-Value Free: 0.334 
• R-Value Work: 0.326 
• Space Group: P 1 2₁ 1

Unit Cell:

Length (Å)	Angle (°)
a = 57.378	α = 90.00
b = 146.764	β = 98.61
c = 135.690	γ = 90.00

Software Package:

Software Name	Purpose
SCALEPACK	data scaling
AMoRE	phasing
CNS	refinement
DENZO	data reduction

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2002-01-16 
• Released Date: 2002-06-07 
• Deposition Author(s): Sundberg, E.J., Li, H., Llera, A.S., McCormick, J.K., Tormo, J., Karjalainen, K., Schlievert, P.M., Mariuzza, R.A.

Revision History 

• Version 1.0: 2002-06-07
  Type: Initial release
• Version 1.1: 2008-04-27
  Type: Version format compliance
• Version 1.2: 2011-07-13
  Type: Version format compliance