FIGURE 8.

Multiple-turnover time course of FEN1 acting upon substrates with flaps of 30 and 45 nt in length. A, multiple-turnover time course comparing cleavage of 30M (filled squares) and 45M (filled diamonds). B, multiple-turnover time course comparing cleavage of 30R (open squares) and 45R (open diamonds). Experimental conditions were 50 nm DNA substrate, 2 nm FEN1, 30 mm HEPES-KOH, 40 mm KCl, 8 mm MgCl₂, 5% (v/v) glycerol, 0.1 mg/ml BSA, pH 7.4. Reactions were performed at 37 °C using an RQF instrument and quenched with EDTA.