336 IMMUNO-CATALYSIS 



cules/LD50. This figure makes botulinus toxin the most potent poison 

 known. Amino acid analysis of the crystalline toxin (Buehler, et ah, 

 1946) showed 14 amino acids of which 10 amino acids are necessary 

 in animal nutrition. It contained 14.9 per cent glutamic acid, the 

 highest value obtained for any amino acid. Qualitative tests for glycine, 

 alanine, proline and hydroxyproline were negative. 



Using a different technique of isolation Abrams, et al. (1946) ob- 

 tained the same toxin in crystalline form in 0.10 to 0.30 saturated 

 ammonium sulfate at 4°. An isoelectric point of pH 5.6 and a total 

 nitrogen of 14.1 per cent was reported. 



b. Biological Action of Botulinus Toxin. In contrast to other bac- 

 terial toxins, botulinus toxin is effective when administered by mouth. 

 This is probably due to the fact that it is relatively resistant to the action 

 of pepsin and trypsin. Bishop and Bronfenbrenner (1936) have re- 

 ported that this toxin acts specifically on the myoneural junctions. 

 Torda and Wolff (1946) using impure toxin reported that small 

 amounts of the toxin decrease the synthesis of acetylcholine in both 

 in vivo and in vitro experiments. They suggest that the toxin, in caus- 

 ing paralysis, acts mainly by decreasing acetylcholine synthesis, which 

 results in functional defects at the myoneural junction. According 

 to a personal communication from Dr. Carl Lamanna of The Johns 

 Hopkins University, Dr. F. Dickens of Middlesex Hospital Medical 

 School of London, England, using pure botulinus toxin failed to repeat 

 the results of Torda and Wolff. 



Lamanna (1948) observed that crystalline and amorphous prepara- 

 tions of toxin causes the agglutination of the red cells from all animal 

 species tested (chicken, guinea pig, rabbit, sheep, man). Unlike the 

 agglutination of the red cells by viruses, toxin does not appear to be 

 taken up by the clumped red cells under the conditions studied. The 

 agglutinating activity of the toxin appears to run parallel with its toxic- 

 ity. This property is specifically prevented by type A antitoxin. The 

 order of adding the reagents namely, toxin, antitoxin, and red cells 

 does not affect the inhibition by antitoxin. The nature of the hemagglu- 

 tinating property of the toxin is not as yet clearly understood. 



c. Crystalline Tetanal Toxin. Pillemer, et al. (1946) reported the 

 crystallization of a toxic protein from the filtrates of Clostridium tetani. 

 The crystalline toxin contained between 50,000,000 to 75,000,000 

 mouse minimal lethal doses (MLD)/mg. of toxin nitrogen. 



