8o 



PHYSIOLOGICAL CHEMISTRY 



NH 2 H H H NH 2 



I I I I 1 

 C C C C C COOH 



I I I I I 

 H H H H H 



FIG. 29. LYSINE PICRATE. 



It is dextro-rotatory and is found in relatively large amount in casein 

 and gelatin. Lysine is obtained from nearly all proteins, but is absent 

 from the vegetable proteins which are soluble in strong alcohol. It is 



FIG. 30. ASPARTIC ACID. 



the mother-substance of cadaverine and has never been obtained in 

 crystalline form. Lysine is usually obtained -as the picrate which is 

 sparingly soluble in water and crystallizes readily. These crystals; are 

 shown in Fig 29. 



