Figure 6.
Bell-shaped dose-response in the active phosphatase case (Figure2c). (a) Bell-shaped response in the zero-order regime when St ≫ Pt. Parameters used are: λ−1 = 10 s−1,λ1 = 1μM−1s−1, k1 = 1 s−1,λ−2 = 10 s−1,λ2 = 20μM−1s−1,k2 =1 s−1,λ−3 = 10 s−1,λ3 = 1μM−1s−1,k3 = 100cs−1,κ−1 = 50 s−1,κ1 = 1μM−1s−1,Pt = 1μM,St = 10μM. The Hill coefficient for the basic model is nH = 2.15. (b) Bell-shaped response outside the zero-order regime when St ≪ Pt: λ−1 =10 s−1,λ1 = 1μM−1s−1,k1 = 1 s−1,λ− 2= 10 s−1,λ2 = 20μM−1s−1,k2 = 1 s−1,λ−3 = 10 s−1,λ3 = 1μM−1s−1,k3 = 100 s−1,κ−1 = 50 s−1,κ1 = 1μM−1s−1,Pt = 1μM,St = 0.1μM. The Hill coefficient for the basic model is nH = 1. In (a)-(b), the full line corresponds to the basic model, the dashed line is numerical results for the extended model and the dotted line shows the tQSSA approximation.