METHODS FOR THE STUDY OF FERMENTS 53 



0) 



d-alanyl-glycyl-glycin 



+ 2 / 



/ N 



d-alanyl-glycin glycocoll 



/~+**\ 



d-alanin glycocoll 

 , ^ v 



+ 2 



(2) + 3 I 



d-alanyl-glycyl-glycin 



d-alanin glycyl-glycin 



/ 



f ^ 



glycocoll glycocoll 



<? * ? 



Finally, we may, for the purpose of tracing pepto- 

 lytic ferments in tissues, inject into the tissues 

 peptones and polypeptides, which contain sparingly 

 soluble amino-acids, and observe directly whether 

 any amino-acids are set free. 



In all these experiments the co-operation of micro- 

 organisms was most carefully excluded, and there 

 can be no doubt that these ferments belong to the 

 tissues themselves. The same holds for ferments 



