28 DYNAMICS OF LIVING MATTER 



of H 2 O 2 by silver, the catalytic action of thallium upon H 2 O 2 is not 

 diminished by HCN.* 



The same authors could show, in general, that the anions of those 

 salts which form insoluble compounds with the metal diminish also the 

 catalytic action of this metal, while the same salts have no inhibiting 

 effect if the catalyzer is a metal which forms soluble compounds with 

 the anion of the salt. 



Kastle and Loevenhart found that certain salts accelerate the action 

 of platinum on the decomposition of hydrogenperoxide. They are 

 inclined to assume that this class of salts acts directly upon the H 2 O 2 , 

 and not upon the catalyzer. 



Everything seems to indicate that the enzymes accelerate the reac- 

 tions in the body by forming intermediary, unstable combinations with 

 the bodies whose reactions they accelerate. These unstable compounds 

 are rapidly decomposed, and this makes the catalyzer free to repeat the 

 action. This makes it clear that a small quantity of the catalyzer can 

 decompose indefinite quantities of the substance. The fact that many 

 enzymes act specifically also harmonizes well with this view. The 

 enzymes, being themselves organic compounds of a complex character, 

 will not form unstable compounds equally well with any organic com- 

 pound. 



Inasmuch as the enzymes are necessary for the chemical processes 

 in living matter, the formation of enzymes is one of the essential 

 functions living matter has to perform. Spitzer and Friedenthal were 

 inclined to assume that the nucleo-proteids act as enzymes. This 

 view, while possible, is not yet proven. 



* Kastle and Loevenhart, Am. Chem, Journal, Vol. 29, p. 397, 1903. 



