110 POISONOUS PROTEINS 



gives similar results to those obtained with the 

 Hopkins-Cole reagent, both with and without 

 furfural. 



11. The proteins and the residues give posi- 

 tive results with the benzaldehyde test (Beichl's 

 reaction). The poisons give negative reactions 

 and the addition of furfural has no effect. 



THE NINHYDEIN EEACTIONS. 



The same investigators have made a study of 

 the ninhydrin test as applied to the original 

 protein and the split products. This reaction 

 has become prominent on account of its delicacy 

 and because of its use in the Abderhalden test. 



The conclusions in this study show that the 

 poisonous split product gives this reaction in 

 the same dilution as the original protein, while 

 the nonpoisonous part fails to respond even in 

 highly concentrated solution. Emerson and 

 Chambers state their results as f olloWs : 



1. Vaughan's protein poisons in dilutions up 

 to 1-10,000 give the ninhydrin reaction. 



2. The proteins from which the poisons are 

 obtained will also give the ninhydrin reactions 

 in dilutions up to 1-10,000. 



3. The cell residue in dilutions of 1-100 does 

 not give the ninhydrin reaction. 



