CATALYSIS AND THE ENZYMES 



is otherwise effective. We call these remteikable 

 substances Anti-Enzymes. Only real enzymes 

 cause the formation of anti-enzymes in animal 

 blood, and this reaction is highly characteristic 

 of true enzymes. It is important to know that 

 each anti-enzyme acts quite specifically only upon 

 that enzyme which was injected into the vein, 

 and upon no other. 



Enzymes are as a rule easily soluble in water, in 

 salt solutions, or in glycerine, but yet some are 

 known which are scarcely soluble in water, such as 

 the fat-splitting enzymes and that which acts upon 

 malt sugar. They pass slowly through animal 

 membranes. Adsorption phenomena are very 

 marked in enzymes. All are greedily taken up by 

 coal or by flakes of blood-fibrin. We prepare 

 enzymes roughly from watery solutions by pre- 

 cipitating with alcohol. Sometimes they may 

 be extracted with glycerine. In a somewhat purer 

 state they are obtained by precipitation with a 

 strong salt-solution, particularly when repeatedly 

 precipitated. When they cannot be dissolved in 

 water, the cells are ground down carefully and 

 some toluol is added to the paste. Such toluol 

 preparations show most of the reactions of the 

 endo-enzymes. It is true that toluol autolysis is 

 not free from disadvantages. 



As a rule the cell-paste is effective on a great 

 number of substances. A paste prepared from 

 root-tips is able to split up starch and cane sugar, 

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