868 16. SPECIFICITY OF INHIBITION 



The relationship between this ratio and the maximal specificity is illus- 

 trated in Fig. 16-1. The maximal specificity is a characteristic of the sys- 

 tem — that is, of the inhibitor and the enzymes involved — and is not 

 dependent on the inhibitor concentration. 



000 



Fig. 16-1. Variation of the maximal specificity possible with the ratio Xj jK^ 



(Eq. 16-7). 



The individual inhibition curves for a situation in which K; IK, = 100 

 are shown in Fig. 16-2 and the variation of the specificity with the inhi- 



FiG. 16-2. Noncompetitive inhibition curves for two enzymes showing the var- 

 iation of specificity with the inhibitor concentration. A', = 1 \\\M and A/ = 100 

 \\\M. The maximal specificity is 0.818 when (I) = 10 niM. 



