Scientific Proceedings (114). 



by sharp convulsive seizures with contraction of the extensor 

 muscles throughout the body. Death occurs in 5 to 15 minutes 

 after the injection and during one of these convulsive seizures. 

 If less than a lethal dose is injected the animal may exhibit all 

 the symptoms described above but will recover completely in 2 

 to 4 hours. 



The toxic substances responsible for these acute symptoms 

 are quite distinct from the specific botulinus toxin and are not 

 neutralized by the specific antitoxin. Besides we obtained similar 

 products from the cultures of "atoxic" strains of B. botulinus, as 

 well as from those of B. sporogents, B. tetani and B. proteus when 

 these organisms were grown on medium composed of minced 

 meat broth. 1 Moreover, these toxic products are not of the nature 

 of bacterial toxins since they are dialyzable, they act only in very 

 large amounts (0.5 c.c. as compared with 0.002 c.c. of botulinus 

 toxin) and since they exert their action immediately upon injec- 

 tion and not after a period of incubation characteristic of all 

 bacterial toxins. In addition the toxic substances in question 

 are thermostable and are not destroyed even in the autoclave 

 when heated in a sealed tube. In the open container, however, 

 and especially in presence of strong alkali, their toxicity diminishes 

 with coincident volatilization of basic products. From the above 

 it is evident that the toxic substances in question are chemical 

 byproducts of the bacterial metabolism. 



We feel justified in reporting these observation for several 

 reasons: In the first place, the presence of toxic substances in 

 cultures of different proteolytic bacteria have been at different 

 times mistaken for specific toxin. 2 Secondly, in connection with 

 the analysis of partly decomposed food products in which the 

 presence of toxins is suspected, one usually injects into a test 

 animal a comparatively large amount of the food extract. Since 

 such extracts may contain poisonous salts, we wish to emphasize 

 the necessity of controlling such animal inoculation by antitoxin 

 neutralization experiments. When the latter is not available the 

 test of thermostability of the toxic substances in neutral as well as 

 in alkaline reaction may indicate the true nature of the substance. 



1 When grown on beef infusion broth or peptone water without minced meat, 

 neither of these organisms produce the toxic substances in question. 



2 Barger, C, and Dale, H. H., Brit. Med. Journ., 1915, 11, 808. 



