CHAPTER XXIII 



PATHOGENIC BACTERIA (Continued) 



Toxic Bacterial Proteins. It has been found that after 

 bacteria have been washed free of all soluble toxin and have 

 been freed of all endotoxin, that the remaining cell wall and cell 

 protoplasm possesses some toxic properties. When injected 

 into an experimental animal these products produce inflamma- 

 tion, necrosis, and pus formation. The effects are not in any 

 sense specific, and injection in different animals may produce 

 different results. The toxic substances of this nature are not 

 confined to pathogenic bacteria alone, but it is not infrequent 

 to find that non-pathogenic bacteria, which have been treated 

 as mentioned above, possess the same properties (B. prodigio- 

 sus, etc.). These toxic substances are separate and distinct 

 from endotoxins and soluble toxins, as is shown in the fact 

 that they resist a temperature of 110 C. for ten minutes when 

 in one per cent sulphuric acid solution. The bacterial pro- 

 teins can be isolated in this way. The substances are un- 

 4oubtedly protein in nature and in all probability some form 

 of nucleo-protein. Wells thinks that they may possibly be 

 derived from the endotoxins by some indirect chemical process. 



There are some diseases, notably tuberculosis and anthrax, 

 leaving out of consideration the mechanical effect of the 

 bacteria in the latter case, which do not seem to be due to any 



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