42 THE AMINO ACIDS 



there for it has been shown quite recently that it may 

 be ingested with certain food products. Thus tyramine 

 occurs in such varieties of cheeses as the Camembert, 

 Roquefort, Emmenthal and even the American cheddar 

 cheese is not free from it. 



In a manner similar to the formation of tyramine 

 we may have amines produced from other amino acids 

 by bacteria. From leucine may be formed isoamyla- 

 mine, thus : 



CH CH 



I I 



CH a CH a 



CH.NH, CH a 



COOH NH 3 



Leucine Isoamylamine 



From tryptophane a corresponding amine may be 

 produced, thus : 



C.CH 2 .CH.NH 2 .COOH /\ C.CH 2 .CH 2 .NH 2 

 H 



NH 

 Tryptophane Indole-ethylamine 



When histidine is subjected to the action of putre- 

 factive bacteria it is transformed to /2-iminazolylethyl- 



