Figure 6.

Effect of 3′-ssDNA tail on the single-turnover unwinding of DNA. A total of 2 nM DNA substrate (16-bp duplex of varying 3′ tails) with 30 nM BLM, 1 mM ATP with 2 µM DNA trap and 5 µM dT₅₆ were first preincubated, respectively, and the reaction was initiated by rapid mixing of the three solutions. (A) Kinetic time-courses. The solid lines are double-exponential fits of the data. (B) Fast-phase, slow-phase and total amplitudes. (C) Rates of the two phases.