VARIATION OF INTRACELLULAR INHIBITION WITH pH 



731 



made to explain these discrepancies. It is predicted that a further devia- 

 tion will be observed when studies are carried to lower pH^'s than pre- 

 viously, namely that curves in this region will fail to remain horizontal. 

 In very few of the published studies has the pH^ been reduced much 

 below the p^^ of the weak acid tested. 



Some of the factors that may modify the configuration of the theoretical 



-I 



- -3 



4 



- -6 



"I — I — r 



I r 



3,5-DINITRO-o-CRESOL 



J I L 



pH 



I 2 3 4 5 6 7 8 



-"I — I — I — I — I — I — I — r 



lODOACETATE 



- -3 



4 



5 



7 



12 3 4 5 6 7 8 



J I I 1 \ I L 



I 2 3 4 5 6 7 8 



pH 



pH 



Fig. 14-23. Simon-Beevers plots for the inhibition of yeast respiration by four 



inhibitors. The soUd lines represent the total inhibitor concentration and the 



dashed lines the concentration of the undissociated forms of the inhibitors. 



(From Simon and Beevers, 1952.) 



