Phage conversion to hemagglutinin production in Clostridium botulinum types C and D

Five toxigenic strains of Clostridium botulinum types C and D were incubated at 37 degrees C for 7 days in 15 ml of the following media: LYG medium, cooked-meat medium, egg meat medium, and N-Z-amine medium. The supernatants of these cultures were tested for hemagglutinin production with 1% erythrocytes obtained from mice, guinea pigs, chickens, sheep, monkeys, and humans. Four toxigenic strains produced hemagglutinin. The highest hemagglutinin titer was obtained with a combination of human erythrocytes and cultures incubated in LYG medium. When the same experiment was carried out with many nontoxigenic strains, hemagglutination was observed in only one strain, C-N71. Strains producing hemagglutinin also produced phages. The phages obtained from toxin- and hemagglutinin-producing strains converted nontoxigenic indicator strains to produce both toxin and hemagglutinin. The phage obtained from a toxin-positive hemagglutinin-negative strain could only induce cultures to produce toxin, and the phage from a toxin-negative hemagglutinin-positive strain could only induce production of hemagglutinin. These studies suggest that the production of hemagglutinin by C. botulinum types C and D is governed by bacteriophages and that hemagglutinin production can be transmitted separately or concomitantly with toxin production.