44 THE AMINO ACIDS 



CH a .CH a .CH a .CH a .CH, 



NH a NH 3 



Cadaverine or Pentamethyldiamine 



Arginine, another amino acid, is the mother sub- 

 stance of putrescine. Arginine under suitable condi- 

 tions yields urea and ornithine, thus : 



CH a .CH a .CH 9 .CH.COOH 

 NH NH, = 



c< NH ' 



< NH i 



Arginine 



NH a CH a .CH a .CH a .CH.COOH 



C = O + NH a NH a 



NH, 

 Urea Ornithine 



Ornithine by cleavage of carbon dioxide yields 

 putrescine or tetramethyldiamine. 



CH a .CH a .CH a .CH.COOH CH a .CH a .CH a .CH a 



NH a NH a -CO, NH a NH, 



Ornithine Putrescine or 



Tetramethyldiamine 



