Structural Basis of Superantigen Action Inferred From Crystal Structure of Toxic-Shock Syndrome toxin-1

Nature. 1994 Jan 6;367(6458):94-7. doi: 10.1038/367094a0.

Abstract

Superantigens stimulate T cells bearing particular T-cell receptor V beta sequences, so they are extremely potent polyclonal T-cell mitogens. T-cell activation is preceded by binding of superantigens to class II major histocompatibility complex (MHC) molecules. To further the structural characterization of these interactions, the crystal structure of a toxin associated with toxic-shock syndrome, TSST-1, which is a microbial superantigen, has been determined at 2.5 A resolution. The N- and C-terminal domains of the structure both contain regions involved in MHC class II association; the C-terminal domain is also implicated in binding the T-cell receptor. Despite low sequence conservation, the TSST-1 topology is similar to the structure reported for the superantigen staphylococcal enterotoxin B4. But TSST-1 lacks several of the structural features highlighted as central to superantigen activity in the staphylococcal enterotoxin B and we therefore reappraise the structural basis of superantigen action.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Bacterial Toxins*
  • Computer Graphics
  • Crystallography, X-Ray
  • Enterotoxins / chemistry*
  • Enterotoxins / immunology
  • Histocompatibility Antigens Class II / immunology
  • Molecular Sequence Data
  • Protein Conformation
  • Protein Structure, Secondary
  • Receptors, Antigen, T-Cell, alpha-beta / immunology
  • Staphylococcus aureus
  • Structure-Activity Relationship
  • Superantigens / chemistry*
  • Superantigens / immunology

Substances

  • Bacterial Toxins
  • Enterotoxins
  • Histocompatibility Antigens Class II
  • Receptors, Antigen, T-Cell, alpha-beta
  • Superantigens
  • enterotoxin F, Staphylococcal
  • enterotoxin B, staphylococcal