Fig. 5. DNA unwinding catalyzed by Hel-1a, R393A, and F438A.

In all reactions, 1 nm of duplex [³²P]DNA substrate was preincubated with indicated amounts of HCV helicase. Reactions were initiated with ATP, incubated at 23 °C for various times, terminated, and analyzed using native polyacrylamide gels. A, reactions containing Hel-1a at 1 nm (□), 5 nm (Δ), 25 nm (◇), 50 nm (○), 100 nm (×), or 200 nm (+). B, reactions containing R393A at 5 nm (□), 25 nm (Δ), 50 nm (◇), 100 nm (○), 200 nm (×), or 300 nm (+). C, reactions containing F438A at 5 nm (□), 25 nm (Δ), 50 nm (◇), 100 nm (○), 200 nm (×), or 300 nm (+). D, initial rates of DNA unwinding for reactions containing various amounts of Hel-1a (□), F438A (◇), or R393A (Δ). Data were fit to Equation 2.