4RGM

Structure of Staphylococcal Enterotoxin B bound to the neutralizing antibody 20B1


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.69 Å
  • R-Value Free: 0.277 
  • R-Value Work: 0.225 
  • R-Value Observed: 0.228 

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, 4RGO

  • 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

    the Department of Medicine and Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York 11790, and the Department of Medicine, Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York 10461 Bettina.Fries@stonybrookmedicine.edu.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Enterotoxin type BAS245Staphylococcus aureusMutation(s): 0 
Gene Names: entB
Find proteins for P01552 (Staphylococcus aureus)
Explore P01552 
Go to UniProtKB:  P01552
Protein Feature View
Expand
  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
20B1 light chainBL214Mus musculusMutation(s): 0 
Protein Feature View
Expand
  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetailsImage
20B1 heavy chainCH223Mus musculusMutation(s): 0 
Protein Feature View
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.69 Å
  • R-Value Free: 0.277 
  • R-Value Work: 0.225 
  • R-Value Observed: 0.228 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 56.467α = 90
b = 83.669β = 91.4
c = 174.731γ = 90
Software Package:
Software NamePurpose
MAR345dtbdata collection
PHASERphasing
REFMACrefinement
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

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