The inhibition of bacteriophagy by bacterial and nonbacterial polysaccharides.

Studies of susceptibility to bacteriophage have shown that polysaccharides associated with somatic bacterial antigens may inhibit the lytic action of bacteriophages upon susceptible homologous organisms. Levine and Frisch (1933 a,b) demonstrated this inhibitory effect with extracts from certain Salmonella and Shigella cultures. Burnet (1934) confirmed these findings; and Gough and Burnet (1934) reported that the agent inactivating the bacteriophage was a complex polysaccharide. The phenomenon was observed among staphylococci by White (1936), Pandit et al. (1936), Rakieten et al. (1936), and Freeman (1937). The relationship between polysaccharide and bacteriophage has been considered to be analogous to that between antigen and antibody, the carbohydrate representing a heat-stable surface antigen. It follows that susceptibility to bacteriophagy may be associated with immunological specificity. Although the most potent extracts were usually obtained from the most susceptible bacteria, some preparations from resistant cultures were inhibitory to bacteriophage activity (Levine and Frisch, 1933a,b; Burnet, 1934; Rakieten et at. 1936). Furthermore, Slanetz and Jawetz (1941) reported that extracts from highly susceptible strains of staphylococci did not adsorb bacteriophage as completely as one would expect, assuming that adsorption preliminary to lysis is a function of a surface antigen. Recently Miller and Goebel (1949) observed that lysis of phase I Shigelkl sonnei by bacteriophages T3, T4, and T7 was specifically inhibited by the purified homologous lipocarbohydrate-protein somatic antigen. This finding supports the notion that some relationship exists between the bacteriophage sensitivity of smooth strains of gram-negative bacilli and their somatic antigens. On the other hand, lysis of phase I and phase II Shigella sonnei by bacteriophages T2 and T6 was not affected by the homologous typespecific antigens. A preliminary report of the nonspecific inhibition of bacteriophagy by starch, glycogen, and gum arabic was presented by Ashenburg et al. (1940). Ellis and Spizizen (1941) confirmed this observation employing starch, gum arabic, inulin, and acetylated gum arabic. Recently Maurer and Woolley (1948) found that