Antigenic, antibiotic and phage receptor activity of proteins from Sh. boydii 15.

The analyzed strain of Sh. boydii 15 induced antibodies against the somatic antigen conjugate, as in most Shigella. Except for the proteinic carrier of the somatic antigen, only a few of the homologous proteinic determinants induced corresponding antibodies; these were illustrated with the help of a serum to proteins from Sh. sonnei. The proteins of Sh. boydii 15 displayed a wide range of antibiotic activity against Shigella, E. coli and Salmonella. Another aspect concerning the biological activities of the proteins isolated from Sh. boydii 15 was its temperate phage receptor activity. This activity was found as well in the free proteins as in the proteinic moiety of the somatic antigen.