1UNS

IDENTIFICATION OF A SECONDARY ZINC-BINDING SITE IN STAPHYLOCOCCAL ENTEROTOXIN C2: IMPLICATIONS FOR SUPERANTIGEN RECOGNITION


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.225 
  • R-Value Work: 0.198 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Identification of a Secondary Zinc-Binding Site in Staphylococcal Enterotoxin C2: Implications for Superantigen Recognition

Papageorgiou, A.C.Baker, M.D.Mcleod, J.D.Goda, S.Manzotti, C.N.Sanson, D.M.Tranter, H.S.Acharya, K.R.

(2004) J.Biol.Chem. 279: 1297

  • DOI: 10.1074/jbc.M307333200

  • PubMed Abstract: 
  • The previously determined crystal structure of the superantigen staphylococcal enterotoxin C2 (SEC2) showed binding of a single zinc ion located between the N- and C-terminal domains. Here we present the crystal structure of SEC2 determined to 2.0 A ...

    The previously determined crystal structure of the superantigen staphylococcal enterotoxin C2 (SEC2) showed binding of a single zinc ion located between the N- and C-terminal domains. Here we present the crystal structure of SEC2 determined to 2.0 A resolution in the presence of additional zinc. The structure revealed the presence of a secondary zinc-binding site close to the major histocompatibility complex (MHC)-binding site of the toxin and some 28 A away from the primary zinc-binding site of the toxin found in previous studies. T cell stimulation assays showed that varying the concentration of zinc ions present affected the activity of the toxin and we observed that high zinc concentrations considerably inhibited T cell responses. This indicates that SEC2 may have multiple modes of interaction with the immune system that are dependent on serum zinc levels. The potential role of the secondary zinc-binding site and that of the primary one in the formation of the TCR.SEC2.MHC complex are considered, and the possibility that zinc may regulate the activity of SEC2 as a toxin facilitating different T cell responses is discussed.


    Related Citations: 
    • Crystallization and Preliminary X-Ray Analysis of a Microbial Superantigen Staphylococcal Enterotoxin C2
      Passalacqua, E.F.,Brehm, R.D.,Acharya, K.R.,Tranter, H.S.
      (1993) J.Mol.Biol. 233: 170
    • Molecular Topology is Important for the Function of Staphylococcal Superantigens
      Tranter, H.,Brehm, R.D.,Acharya, K.R.
      (1995) Bacterial Superantigens: Structure, Function and Therapeutic Potential --: 5
    • Structural Basis of Superantigen Action Inferred from Crystal Structure of Toxic-Shock Syndrome Toxin-1
      Acharya, K.R.,Passalacqua, E.F.,Jones, E.Y.,Harlos, K.,Stuart, D.I.,Brehm, R.D.,Tranter, H.S.
      (1994) Nature 367: 94
    • Structure of the Superantigen Enterotoxin C2 from Staphylococcus Aureus Reveals a Zinc-Binding Site
      Papageorgiou, A.C.,Acharya, K.R.,Shapiro, R.,Passalacqua, E.F.,Brehm, R.D.,Tranter, H.S.
      (1995) Structure 3: 769


    Organizational Affiliation

    Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
ENTEROTOXIN TYPE C-2
A
239Staphylococcus aureusMutation(s): 0 
Gene Names: entC2
Find proteins for P34071 (Staphylococcus aureus)
Go to UniProtKB:  P34071
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

Download SDF File 
Download CCD File 
A
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.225 
  • R-Value Work: 0.198 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 42.500α = 90.00
b = 44.540β = 90.00
c = 131.650γ = 90.00
Software Package:
Software NamePurpose
CNSrefinement
SCALEPACKdata scaling
DENZOdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2003-11-13
    Type: Initial release
  • Version 1.1: 2011-05-08
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance