Figure 5.

Effect of negative feedback. (A) Protein (P in Fig. 1) concentration at different ${\gamma }_2$ values as a function of the logarithm of $k_F$, the production rate constant of enzyme E that produces the metabolite M, relative to $k_{F0}=1$ s⁻¹. The parameters are given in Table 1 and Table 2 except $k_{t2}$. (B) The extent of regulation expressed in terms of protein level as a function of the logarithm of association rate constant k_b for metabolite binding. The parameters are listed in Table 1 and Table 2 except $k_b$ and $k_{-b}$. $K_D$ is fixed at 10 nM.