FIG. 8.

Effect of nucleotides on BER of uracil in DNA by A. fulgidus cell extract. (A) Results of a typical experiment comparing ATP, ADP, and NAD as stimulatory agents for conversion of a repair intermediate to a repair product following 60 min of incubation. (B) Average concentrations of repair intermediate and repair product as determined in three independent experiments, as shown in panel A. Substrate 3 (0.5 pmol) was incubated with A. fulgidus protein extract (17 μg) at 60°C in 45 mM HEPES-KOH (pH 7.8), 0.4 mM EDTA, 1 mM DTT, 70 mM KCl, 5 mM MgCl₂, 2% (vol/vol) glycerol, 1 μg/μl BSA, 13 μM dATP, 13 μM dTTP, 13 μM dGTP, [α-³²P]dCTP in a 15-μl (final volume) mixture.