Figure 6.

Role of $k_{t2}$ on negative feedback. (A) The fraction of fully transcribed RNA, $f_{tra}=1-f_{ter}$, as a function of $k_{t2}/k_{-f2}$. The numbers give values of $k_F/k_{F0}$ with $k_{F0}=1$ s⁻¹. The dependence of $f_{tra}$ on $k_{t2}/k_{-f2}$ shows three regimes: thermodynamic controlled regime for low $k_{t2}$ ($k_{t2}/k_{-f2}<0.025$, or $k_{t2}<0.1k_{-b}$), aptamer folding dominated regime for high $k_{t2}$$\left(k_{t2}>k_{-f2}\right)$, and intermediate regime with significant metabolite binding. (B) The P concentration as a function of $k_{t2}/k_{-f2}$ at different $k_F/k_{F0}$ values (as described in (A)).