REGENERATIVE SYSTEMS 357 



Since the total concentration of cofactor remains constant: 



(B), = (B) + (BX) 

 the following quadratic expression may be derived for (BX): 



(1 - R){BXr + [(B),(R - 1) + RK, + ^,,](BX) - (B),K,, = (7-43) 



where: 



R = 





1 + 



K„ 



(C) 



(AX) I (C) + K, 



(7-44) 



Fig. 7-23. Noncompetitive inhibition of Ej in the cyclic system shown 

 in Fig. 7-16. (M)^ = 1 mM. 



The concentration of BX thus depends on the concentrations of all the 

 components of the system, including the enzymes, and all the constants 

 of the individual reactions. In order to make the results more general, 

 the ratio (BX)/(B); will be used to express the state of the regenerated 

 substance, which will be called the "regenerant" for convenience. 



