The nature of toxins produced by Bacillus cereus BIS-59

Eight strains of Bacillus spp. were examined for production of toxin(s). Three strains of Bacillus cereus produced toxins lethal to mice. The culture filtrate of Bacillus cereus BIS-59 contained two lethal toxins. One was a hemolysin and the other a nonhemolytic glycoprotein. The growth of cells in fresh beef infusion broth resulted in high toxin production, compared to growth in tryptone-glucose-yeast extract or nutrient broth. Separate identities for the two toxins from B. cereus BIS-59 were established on the basis of hemolytic activity, separation profiles on Sephadex gel filtration, responses to heat and radiation and kinetics of their production during the growth of the organism.