DONALD F. BENT, AND LEO LEVINE. Tetanus toxin production in the absence of protein. Appl. Microbiol. 10:146-152. 1962. A modification of the MIueller medium for tetanus toxin production is presented, on which an adapted strain produces high yields of toxin (70 to 90 flocculating units per ml) in the absence of animal protein extracts. The range of iron concentration in the medium was established within which the toxigenic activity of the culture can be made to vary, and the mathematical nature

A modification of the Mueller medium for tetanus toxin production is presented, on which an adapted strain produces high yields of toxin (70 to 90 flocculating units per ml) in the absence of animal protein extracts. The range of iron concentration in the medium was established within which the toxigenic activity of the culture can be made to vary, and the mathematical nature of the variation is presented. Darkening of cultures during incubation indicates departure from optimal conditions. Heat input to the medium during autoclaving, originally undertaken solely for purposes of sterilization, is an important physicochemical factor in the toxigenicity of the culture.

No abstract

Summary By the use of the continuous-flow hangingcurtain electrophoresis apparatus developed by Karler, it has been possible to purify the murine toxin of Pasteurella pestis to such an extent that the final preparation exhibited only 1 band in the very sensitive gel precipitation techniques of Oudin and Ouchterlony. The final product had an intraperitoneal LD50 of 0.7μg for 16 to 20-g mice, and an intravenous LD50 of 0.2μg. Experiments are described which suggest that even this relatively pure toxin molecule may still contain portions which are not necessary for toxicity.