Three-dimensional structure of the complex between a T cell receptor beta chain and the superantigen staphylococcal enterotoxin B.
Superantigens (SAGs) are a class of immunostimulatory proteins of bacterial or viral origin that activate T cells by binding to the V beta domain of the T cell antigen receptor (TCR). The three-dimensional structure of the complex between a TCR beta chain (mouse V beta8.2) and the SAG staphylococcal enterotoxin B (SEB) at 2.4 A resolution reveals why SEB recognizes only certain V beta families, as well as why only certain SAGs bind mouse V beta8.2. Models of the TCR-SEB-peptide/MHC class II complex indicate that V alpha interacts with the MHC beta chain in the TCR-SAG-MHC complex. The extent of the interaction is variable and is largely determined by the geometry of V alpha/V beta domain association. This variability can account for the preferential expression of certain V alpha regions among T cells reactive with SEB.
Li
H
H
Center for Advanced Research in Biotechnology, University of Maryland Biotechnology Institute, Rockville 20850, USA.
Llera
A
A
Tsuchiya
D
D
Leder
L
L
Ysern
X
X
Schlievert
P M
PM
Karjalainen
K
K
Mariuzza
R A
RA
D000818:Animals; D018360:Crystallography, X-Ray; D004768:Enterotoxins / Q000737:chemistry* / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000737:chemistry / Q000276:immunology; D051379:Mice; D008958:Models, Molecular; D010446:Peptide Fragments / Q000737:chemistry* / Q000276:immunology; D010455:Peptides / Q000737:chemistry / Q000276:immunology; D011487:Protein Conformation; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000737:chemistry* / Q000276:immunology / Q000502:physiology; D013211:Staphylococcus aureus / Q000276:immunology*; D018089:Superantigens / Q000737:chemistry* / Q000276:immunology
D004768:Enterotoxins; D000949:Histocompatibility Antigens Class II; D010446:Peptide Fragments; D010455:Peptides; D016693:Receptors, Antigen, T-Cell, alpha-beta; D018089:Superantigens; C109168:T-cell receptor Vbeta 8.2; C031818:enterotoxin B, staphylococcal