36 POISONOUS PROTEINS 



and Millon tests. None give the Molisch test, 

 thus showing the absence of carbohydrate. 

 Some give the Adamkiewicz and Liebermann 

 tests while others do not. This test is believed 

 to be due to the presence of tryptophane. The 

 fact that the poisons from certain proteins do 

 not respond to these tests indicates that 

 Doerr's assumption that the poisonous action is 

 due to the presence of this group is without 

 support. The poison gives the Millon test most 

 strikingly and in high dilution. This test is be- 

 lieved to indicate the presence of tyro sine and 

 it is interesting to note that gelatine which con- 

 tains no tyrosine does not yield the poison. 

 Aqueous solutions are distinctly acid to litmus 

 and this reaction is due to some organic body. 

 * Neutralization with alkalis and alkaline earths 

 weaken the action of the poisons. Poisons from 

 some proteins appear to form definite com- 

 pounds with calcium and magnesium and at 

 least some of the calcium bodies are inert. In 

 the dry state the protein poison forms a brown- 

 ish powder varying somewhat in shade with the 

 protein from which it is obtained. All prepara- 

 tions have the same marked odor. It is much 

 mbre freely soluble in absolute alcohol than in 

 water. Whether it should be called a protein or 

 not is a question. Proteins should not be solu- 



