THE PROTEINS AND THEIR METABOLISM 113 



Ornithin gives rise to glucose to the extent of three of its carbon atoms. 

 (Dakin, Ringer, Frankel and Jonas, 1013 (&)). After deamination it 

 probably passes through succinic acid stage. 



COOH 



CH 2 CH 2 



| Deamination - * Glucose 



C1L> and oxidation CH 2 



o COOH 



I 



COOH 



PlienyWanin and lijrosin have the same fate in the animal body. The 

 former can be converted into the latter on perfusion through a surviving 

 liver. (Ernbden and Balder, 1913). 



OH 



CHNH 2 



COOH 



Phenylalanin 



They are burned in the body, giving rise to acetone bodies in the in- 

 termediary metabolism (Ringer and Lusk ; Dakin ; O. Neubauer and Gross, 

 1010: E/Schmitz, 1910), but not to glucose. 



Phenylalanin and tyrosin, as will be seen later, are indispensable 

 amino acids (see page 000) i. e., an animal cannot maintain itself on 

 proteins which do not contain these acids. When one views that fact in 

 conjunction with the relationship that exists between the structure of the 

 adrenalin molecule and tyrosin, one is justified in the conclusion that these 

 two amino acids form the building material for adrenalin, even though 

 we have no direct proof that such is the case. (Stolz, 1904; E* Fried- 

 man, 1905 (a) ; Abel and Crawford, 1897). 



OH 

 /\OH 



CHOH 



CH 2 NH CH 8 



Adrenalin or Epinephrin 



