Studies on immunity to toxins of Clostridium botulinum. III. Preparation, purification, and detoxification of type E toxin.

Although type E strains of Clostridium botulinum have been implicated in human botulism since 1936, no studies of the isolation or characterization of the toxin have been reported. Crude toxoids have been prepared by various workers for immunization of animals and preparation of antitoxin. Barron and Reed (1954) presented a systematic study of methods for preparation of crude alum precipitated type E toxoid, employing cultures grown in cellophane dialysis bags. Publications from our laboratory have described procedures for production and purification of C. botulinum types A, B, and C toxins suitable for preparations of purified toxoids (Duff et al., 1957a, 1957b; Cardella et al., 1956). Duff et al. (1956) reported that the intraperitoneal toxicity for mice of crude and partially purified type E toxin was increased strikingly when the culture was incubated with trypsin. The present paper describes an extension of these studies to the preparation of partially purified type E toxoid. The purification and detoxification of nonactivated and trypsin activated type E toxins were compared, and the immunization of mice by aluminum phosphate toxoids was investigated.2