[Isolation and immunochemical study of the toxic complex of Cl. botulinum type F]

The toxic comples of Cl. botulinum, type F, was separated into the toxic and nontoxic protein fractions by the methods of ion exchange chromatography and gel filtration in accordance with a specially devised purification scheme. Highly purified, electrophoretically and serologically homogeneous toxin with a molecular weight of 150,000 and potency equal to 10 X 10(6) DLM per 1 mg of protein was isolated from the toxic fraction. The nontoxic protein component had faintly pronounced hemagglutinating properties and was essentially different from type A and B hemagglutinins. The toxic complex of Cl. botulinum, type F, was shown to contain a proteolytically active fraction.