ENZYMES AND THEIR ACTION 9 



ph&tese the enzyme which builds up phosphoric acid esters of carbo- 

 hydrates in distinction from phosphates which causes their cleavage. 

 In the same way he would differentiate the lipolytic enzymes into Upases 

 and lipeses. 



In respect to many enzymes it has been found that the law govern- 

 ing the action of inorganic catalyzers is directly applicable, i.e., that 

 the intensity is almost directly proportional to the concentration of the 

 enzyme. In the case of enzymes, however, there is a difference in that a 

 maximum intensity is soon reached and that subsequent concentration 

 of the enzyme is productive of no further increase in intensity. The en- 

 zymes which have been shown to obey this linear law are lipase, sucrase, 

 rennin, and trypsin. In certain instances, where this law of direct 

 proportionality between the intensity of action and the concentration 

 of enzymes does not hold, it has been found that the Schutz-Borissow 

 law, first experimentally demonstrated by E. Schtitz, was applicable. 

 This is to the effect that the intensity is directly proportional to the 

 square root of the concentration, or conversely, that the relative con- 

 centrations of enzyme preparations are directly proportional to the squares 

 of the intensities. 1 



It has been shown that there are certain substances which possess 

 the property of directly inhibiting or preventing the action of a cata- 

 lyzer. These are called anti-catalyzers or paralyzers and have been com- 

 pared to the anti-toxins. Related to this class of anti-catalytic agents 

 stand the anti-enzymes. The first anti-enzyme to be reported was the 

 antirennin of Morgenroth. This was produced by injecting into an 

 animal increasing doses of rennet solution, whereupon an "anti" 

 substance was subsequently found both in the serum and in the milk, 

 which prevented the enzyme rennin from exerting its normal activity 

 in the presence of casein. In other words, anti-rennin had been 

 formed in the serum of the animal, 2 through the repeated injections of 

 rennet solution. Since the discovery of this anti-enzyme, anti-bodies 

 have been demonstrated for pepsin, trypsin, lipase, urease, amylase, 

 laccase, tyrosinase, emulsin, papain, and thrombin. According to 

 Weinland, the reason why the stomach does not digest itself is, that 

 during life there is present in the mucous membrane of the stomach an 

 anti-enzyme (anti-pepsin) which has the property of inhibiting the action 

 of pepsin. A similar substance (an ti- trypsin) is present in the intestinal 

 mucosa as well as in the tissues of various intestinal worms. Some in- 

 vestigators are not inclined to accept the enzyme nature of these 

 inhibitory agents as proven. 



1 This Schutz-Borissow law is not generally applicable. 



2 Serum is normally anti-try ptic. 



