38 PROTEIN POISONS 



that these animals died from infection, and the object in 

 inoculating them was to show that the culture contained 

 living, virulent bacteria, while its filtrate was without 

 effect on animals. However, it might be claimed that the 

 poison, although in solution in the beef-tea, will not pass 

 through porcelain. This suggestion is reasonable, and 

 calls for further experimentation ; consequently an unweighed 

 portion of the dead cellular substance of the colon bacillus 

 was suspended in water, heated in the autoclave at 154 

 under 2 kilos of pressure, and filtered through porcelain. 

 Four cubic centimeters of this clear, sterile filtrate injected 

 intra-abdominally into a guinea-pig caused death within 

 thirty-six hours, and section showed the same lesions that 

 are found after death from either the living bacillus or the 

 dead cellular substance. This demonstrates that when 

 the bacterial cells have been disrupted by superheated 

 steam, their poisonous constituent becomes to some extent 

 soluble in water, and may be passed through porcelain. 

 Furthermore, experiment showed that colon cultures when 

 boiled in open dishes and filtered through porcelain supplied 

 inert filtrates. This indicates that the disrupting effect 

 of a high temperature is necessary to the extraction of the 

 poison from the cell. 



Filtrates from living cultures of the diphtheria bacillus 

 contain a toxin which is a secretion of the living micro- 

 organism. The colon bacillus produces no such active 

 toxin. Old, dead cultures of the colon or typhoid bacillus 

 may contain soluble poisons, but these are not secretions 

 of the living cells. They come from the autolysis of the 

 dead cells, and, as we shall see later, they are not properly 

 toxins, capable of producing antibodies, but are chemical 

 poisons. Moreover, the toxin of the diphtheria bacillus is 

 specific, while the cellular poison is not. 



2. The poison is not extracted from the bacterial cell 

 by dilute saline solution, alcohol, or ether, either at ordi- 

 nary temperature or at the boiling-point of these fluids. 

 Extracts of the cellular substance of the colon bacillus with 

 these agents were repeatedly made, filtered, evaporated 



