Figure 3.

(a) Cartoons showing four consecutive steps as [BP]G* passes through the active site region of BF. Color code: red rectangle, [BP]G*; green rectangle: the partner opposite [BP]G*; purple rectangle: the base to be replicated after [BP]G*; orange ellipse, the pre-insertion site; light blue ellipse, the insertion site; grey ellipse, the post-insertion site. Adapted from (35). (b) [BP]G* modified DNA structures used in the four steps. Minor groove hydrogen bonding interactions between BF and the +1 base pair are indicated. N = A/C/G/T. Base pair numbers given are independent of the position numbers in Figure 2.