26 Living and Dead Matter and 



obtained not of lactose but of isolactose; the latter, 

 however, is not decomposed by the enzyme lactase. 



E. F. Armstrong has worked out a theory which 

 tries to account for this striking phenomenon by assum- 

 ing "that the enzyme has a specific influence in pro- 

 moting the formation of the biose which it cannot 

 hydrolyze."' The theory is very ingenious and seems 

 supported by fact. This then would lead to the result 

 that certain hydrolytic enzymes may have a synthetic 

 action but not in the manner suggested by van't Hoff. 



The principle enunciated by Armstrong, that in the 

 synthetic action of hydrolytic enzymes not the origi- 

 nal compound but an isomer is formed which can 

 not be hydrolyzed by the enzyme, may possibly be 

 of great importance in the understanding of life phe- 

 nomena. It shows us how the cell can grow in the 

 presence of hydrolytic enzymes and why in hunger the 

 disintegration of the cell material is so slow. It was 

 at first thought that the formation of isomers con- 

 tradicted the idea of the reversible action of enzymes, 

 but this is not the case ; on the contrary, it supports it 

 but makes an addition which may solve the riddle of 

 what Claude Bernard called the creative action of 

 living matter. We shall come back to this problem 

 in the last chapter. 



Kastle and Loevenhart demonstrated the synthesis 

 of a trace of ethylbutyrate by lipase if the latter enzyme 



* Armstrong, E. F., Proc. Royal Soc, 1905, B. Ixxvi., 592. 



