Figure 4.

Probability of a backwards step vs. DNA position for two sequences, one of the form 3′ …AAAGGGCC… 5′ (red) and one of the form 3′ …CCCGGGAAA… 5′ (blue). Changing the context around the ‘GGG’ motif causes the probability of a backwards step to change from 36% to 86% at the location of the central guanine suggesting additional sequence context also contributes to the observed backstepping behavior. Each of these plots are time ordered, so that 3′ is on the left and 5′ is on the right. Gaps are DNA positions where an ion-current state was similar to an adjacent state. All error bars are SEM.