Figure 3.

DNA unwinding kinetics under steady-state conditions. A total of 60 nM DNA substrate (16-bp duplex with a 15-nt 3′ tail), BLM of varying concentrations with 1 mM ATP, and 20 µM DNA trap were first preincubated, respectively, in three syringes and the reaction was initiated by rapid mixing of them. (A) Typical kinetic time-courses. The solid lines are double-exponential fits of the data. (B) Initial unwinding rate obtained from the fittings. Each data point represents the average value of three independent measurements.