WAYS OF EXPRESSING INHIBITION RATE 



537 



but type C is probably generally preferable, especially when the uninhibited 

 control rate varies during the experimental period. In studies that are 

 directed towards inhibition, it would seem to be best to show directly 

 the variation of the inhibition with time, and yet this method of plotting 

 is actually seldom used. Of course, there are no invariable rules and the 

 plotting technique must always be adapted to the nature of the inhibition 

 and the particular objectives in the investigation. 



TYPE A 



TIME- 



RATE 



TYPE B 



TIME- 



TYPE C 



TIME— ► 



Fig. 12-1. The usual ways of representing 

 the changes of inhibition with time. 



Inhibition of a pure enzyme can often be treated on the basis of an 

 assumed mechanism and equations derived by which the data can be in- 

 terpreted and from which physically significant constants can be calculated. 

 However, in complex systems, such a procedure is usually impossible and 

 more general methods of mathematically expressing the inhibition rate 

 must be used. The object in such cases is to find an equation that will ade- 

 quately represent the data and which contains a constant or constants 



