Figure 4.

Schematic of the model for Eq. 3. Unit vectors a and b specify orientation of the DNA segments between the C1′ atoms of the +1 to 0 and 0 to −1 residues, respectively, for the open conformation of the enzyme; vectors âand b̂denote the same for the closed conformation. Angles α and β or α̂ and β̂ specify the orientation of the corresponding vectors with respect to the direction of the local applied force vector. Angles between the segments are denoted by γ or γ̂.