FURTHER FATE OF AMINO ACIDS 111 



into glucose, whereas three of the carbon atoms con- 

 tained in aspartic and glutamic acids were so changed. 

 The stages through which these amino acids are 

 carried have been outlined by Lusk. In the first place 

 it is assumed that the initial change is a hydrolytic 

 deamination whereby ammonia is formed and a 

 hydroxy group is added to the denitrogenized amino 

 acid. According to this view glycocoll would first be 

 changed to glycolic acid, which on reduction would 

 yield glycolic aldehyde, three molecules of which will 

 form one molecule of dextrose. The chemical rela- 

 tionships are shown below : 

 *y 



CH a .NH a CH a .OH 

 3 + H a O = 3 | - 3 O = 



COOH COOH 



Glycocoll Glycolic acid 



CH a OH 



3 | = C 6 HX) 6 



CHO 



Glycolic Dextrose 



aldehyde 



For alanine the changes undergone are a direct trans- 

 formation into lactic acid which is well known to give 

 rise to dextrose production. 



CH 8 CH, 



2 CHNH a + H a O = 2 CHOH = C 6 H,O, 



I I ^ 



COOH COOH 



Alanine Lactic acid Dextrose 



