4RGO

Structure of Staphylococcal Enterotoxin B bound to the neutralizing antibody 14G8


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.189 
  • R-Value Work: 0.142 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Mechanisms mediating enhanced neutralization efficacy of staphylococcal enterotoxin B by combinations of monoclonal antibodies.

Dutta, K.Varshney, A.K.Franklin, M.C.Goger, M.Wang, X.Fries, B.C.

(2015) J.Biol.Chem. 290: 6715-6730

  • DOI: 10.1074/jbc.M114.630715
  • Primary Citation of Related Structures:  4RGM, 4RGN

  • PubMed Abstract: 
  • Staphylococcal enterotoxin B (SEB) is a superantigen that cross-links the major histocompatibility complex class II and specific V-β chains of the T-cell receptor, thus forming a ternary complex. Developing neutralizing mAb to disrupt the ternary com ...

    Staphylococcal enterotoxin B (SEB) is a superantigen that cross-links the major histocompatibility complex class II and specific V-β chains of the T-cell receptor, thus forming a ternary complex. Developing neutralizing mAb to disrupt the ternary complex and abrogate the resulting toxicity is a major therapeutic challenge because SEB is effective at very low concentrations. We show that combining two SEB-specific mAbs enhances their efficacy, even though one of the two mAbs by itself has no effect on neutralization. Crystallography was employed for fine-mapping conformational epitopes in binary and ternary complexes between SEB and Fab fragments. NMR spectroscopy was used to validate and identify subtle allosteric changes induced by mAbs binding to SEB. The mapping of epitopes established that a combination of different mAbs can enhance efficacy of mAb-mediated protection from SEB induced lethal shock by two different mechanisms: one mAb mixture promoted clearance of the toxin both in vitro and in vivo by FcR-mediated cross-linking and clearance, whereas the other mAb mixture induced subtle allosteric conformational changes in SEB that perturbed formation of the SEB·T-cell receptor·major histocompatibility complex class II trimer. Finally structural information accurately predicted mAb binding to other superantigens that share conformational epitopes with SEB. Fine mapping of conformational epitopes is a powerful tool to establish the mechanism and optimize the action of synergistic mAb combinations.


    Related Citations: 
    • Generation, characterization, and epitope mapping of neutralizing and protective monoclonal antibodies against staphylococcal enterotoxin B-induced lethal shock.
      Varshney, A.K.,Wang, X.,Cook, E.,Dutta, K.,Scharff, M.D.,Goger, M.J.,Fries, B.C.
      (2011) J.Biol.Chem. 286: 9737


    Organizational Affiliation

    From the New York Structural Biology Center, New York, New York 10027, dutta@nysbc.org.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Enterotoxin type B
S
245Staphylococcus aureusGene Names: entB
Find proteins for P01552 (Staphylococcus aureus)
Go to UniProtKB:  P01552
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
14G8 heavy chain
H
222N/AN/A
Protein Feature View is not available: No corresponding UniProt sequence found.
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
14G8 light chain
L
214N/AN/A
Protein Feature View is not available: No corresponding UniProt sequence found.
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ACT
Query on ACT

Download SDF File 
Download CCD File 
S
ACETATE ION
C2 H3 O2
QTBSBXVTEAMEQO-UHFFFAOYSA-M
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.189 
  • R-Value Work: 0.142 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 84.576α = 90.00
b = 85.292β = 90.00
c = 115.017γ = 90.00
Software Package:
Software NamePurpose
MAR345dtbdata collection
PHASERphasing
HKL-2000data reduction
REFMACrefinement
HKL-2000data scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2015-01-21
    Type: Initial release
  • Version 1.1: 2015-01-28
    Type: Database references
  • Version 1.2: 2015-04-01
    Type: Database references