PDB 1LO5 deposited: 2002-05-06 modified: 2009-02-24
Title Crystal structure of the D227A variant of Staphylococcal enterotoxin A in complex with human MHC class II
Authors Forsberg, G., Petersson, K., Thunnissen, M., Walse, B.
Structure factors resolution 3.2 rfactor 0.245 rfree 0.339
DPI 1.91 theoretical min: 0.88

Although the biological properties of staphylococcal enterotoxin A (SEA) have been well characterized, structural insights into the interaction between SEA and major histocompatibilty complex (MHC) class II have only been obtained by modeling. Here, the crystal structure of the D227A variant of SEA in complex with human MHC class II has been determined by X-ray crystallography. SEA(D227A) exclusively binds with its N-terminal domain to the alpha chain of HLA-DR1. The ability of one SEA molecule to crosslink two MHC molecules was modeled. It shows that this SEA molecule cannot interact with the T cell receptor (TCR) while a second SEA molecule interacts with MHC. Because of its relatively low toxicity, the D227A variant of SEA is used in tumor therapy.

Structure 2002 Dec; 10(12):1619-1626 doi:10.1016/S0969-2126(02)00895-X

Cross References
Database source Identifier Description
PubMed 12467569 STRUE6
Biomolecule Structure Assembly Serial Assembly Type Conformational State Chains Ligands Atoms
1LO5/1 1LO5 1 tetramer 0 4 0 4758