Structural Studies of a novel cluster of superantigen-like proteins from Staph. Aureus.
The SET proteins were discovered by our collaborators (Williams et al) at the Eastman Dental institute in London, UK. This group of proteins all share the "staphylococcal superantigen motif", and share in the order of 25% sequence homolgy with the other, established supoerantigens.
We have now solved several structures of SET-1. This follows the structure determination of SET-3 by Arcus et al. Both SET-1 and SET-3 look like superantigens, with an rmsd between SET-1 and SPE-C (its closest homologue) of around 1.5angstoms.
We are currently engaged in efforts to discover the true function of these proteins, which seem to have some sort of immuno-modulatory effect. This immunology work is being carried out in collaboration with the Anthony Nolan research institute, Royal Free Hospital, London.
Arcus, V. L., Langley, R., Proft, T., Fraser, J. D., Baker, E. N.: The Three-Dimensional Structure of a Superantigen-Like Protein, Set3, from a Pathogenicity Island of the Staphylococcus Aureus Genome J.Biol.Chem. 277 pp. 32274 (2002)
Williams R.J., Ward J.M., Henderson B., Poole S., O'Hara B.P., Wilson M., Nair S.P. "Identification of a novel gene cluster encoding staphylococcal exotoxin-like proteins: characterization of the prototypic gene and its protein product, SET1." Infect. Immun. 68:4407-4415(2000).