Fig. 3.
From enzyme content of E. coli populations to in vivo DNA looping free energies. (a) Measured repression levels, Rloop, as a function of the distance between operators from Muller et al. (7). (b) Inferred free energies of looping using Eq. 1 and Rloop as in a, with Rnoloop = 135 and [N] = 75 nM (7). (c) Fourier analysis of the operator distance dependence of the free energy. (d) Behavior of the two main periodic components of the free energy of looping: ΔGl(l) = 8.79 – 0.68sin(2π l/10.9 – 0.94) – 0.30sin(2π l/5.6 – 2.32), where l is the distance between operators.