88 CONCENTRATION OF ENZYME 



Armstrong), Rennin (Segelcke u. Storch, Soxhlet, Lorcher, Duclaux, 

 Fuld), Lipase (Kastle u. Loewenhart), Trypsin (Bayliss). 



In the case of other ferments, however, although the same 

 falling of? to a maximum value at an upper limit, at which the 

 percentage of ferment is still very low, is observed in all cases, 

 it is found that even well below this limit of maximum effect 

 the linear law is not obeyed of direct proportionality between 

 concentration of enzyme and intensity of action. 



In most such cases, the majority of experimenters have arrived 

 at the conclusion that the law, first empirically deduced from 

 experiments upon pepsin by E. Schiitz and known as " Schiitz's 

 law," is that which best expresses the effects of concentration 

 upon intensity of action within a certain range. The law is that 

 the intensity is directly proportional to the square root of the 

 concentration, or put conversely, that the relative concentrations 

 of enzyme are directly proportional to the squares of the inten- 

 sities (that is, the amounts changed in equal times). Expressed in 

 an equation, if 7^ and & 2 are the velocity constants (or quantities 

 converted in equal times) at two different concentrations of 

 enzyme c x and c 2 , then " Schiitz's law " is that 



The law has been most worked out in the case of pepsin by 

 E. Schiitz, J. Schiitz, Huppert and J. Schiitz, and Borissow ; but 

 according to Pawlow and his co-workers, using Mett's method, it 

 also holds for the tryptic and diastatic enzymes of the pancreas, 

 in addition to pepsin. 



The whole subject, however, deserves to be thoroughly worked 

 out anew, for there is a want of concordance in methods and 

 results amongst the different workers, who have not only em- 

 ployed different methods and different stages in the reaction for 

 different enzymes, but also for the same enzyme. Thus in, the 

 case of trypsin Bayliss finds, as stated above, that the law at any 

 rate for dilute solutions is approximately a linear one, while 

 Pawlow, using a different method (Mett's), finds the " Schiitz law " 

 followed. Again, while Huppert and J. Schiitz found the Schiitz 

 law followed for not too concentrated solutions on using dis- 

 solved proteid (egg albumin), they found with the Mett's tube 

 method on coagulated egg albumin, that this law was not obeyed, 



