[Immunochemical study of Clostridium botulinum type B toxin]

Fractionation of type B. Cl. botulinum toxin, a protein complex, was carried out; as a result, 3 fractions, alpha, beta, and gamma, were isolated in a pure form, alpha-fraction, or neurotoxin, is highly toxic (5-10.10(7) LDm per 1 mg of protein), beta-fraction showed hemagglutinating activity (64-128 HAU per 1 mg of protein), gamma-fraction was not biologically active. The molecular weight of alpha and gamma-fractions was 150,000. All these fractions had antigenic properties. alpha-fraction was serologically specific. beta- and gamma-fractions showed incomplete serologic identity.