FIGURE 6.

Binding curves from Alexa Fluor-labeled DNA substrates titrated with Gp59. DNA binding assays were performed as described under “Experimental Procedures.” Buffer contained the following components: 20 mm Tris acetate, pH 7.4, 10 mm magnesium acetate, 90 mm potassium acetate, and 1 mm DTT. All DNA substrates were 25-mers either as single-stranded DNA (A) or annealed to form double-stranded DNA (B) or fork DNA structures (C) as depicted with the relative position of the Alexa Fluor 546 probe indicated by the star. In each experiment, the concentration of the labeled Oligo 2 was 2 μm nucleotides. When present, unlabeled Oligo 3 or Oligo 4 was added in the same concentration for annealing as described under “Experimental Procedures.” Error bars represent the S.D. of the results of a minimum of two experiments.