immunoglobulin-binding

That is, whereas antigens are the " target " of antibodies, immunoglobulin-binding proteins " attack " antibodies.

When the structure of individual SAg domains has been compared to other immunoglobulin-binding streptococcal proteins ( such as those toxins produced by E. coli ) it was found that the domains separately resemble members of these families.

The beta-grasp domain has some structural similarities to the beta-grasp motif present in immunoglobulin-binding domains, ubiquitin, 2Fe-2 S ferredoxin and translation initiation factor 3 as identified by the SCOP database.