Fig. 3

(a) α-TP dose-dependence of concentration changes in nucleosides and products when a solution of 100 μM each of dCyd, dGuo, dThd, and dAdo with 0–5 mM α-TP was irradiated with UV light through a 300-nm longpass filter for 10 min at pH 7.4 and 37°C. (b) Time-course of the concentration changes in nucleosides when a solution of 100 μM each of dCyd, dGuo, dThd, and dAdo with 5 mM α-TP in 100 mM potassium phosphate buffer at pH 7.4 was irradiated with UV light through a 300-nm longpass filter for 0–10 min at a temperature of 37°C. (c) Trolox dose-dependence of the concentration changes in nucleosides and products when a solution of 100 μM each of dCyd, dGuo, dThd, and dAdo with 0–5 mM Trolox was irradiated with UV light through a 300-nm longpass filter for 10 min at pH 7.4 and 37°C. (d) Time-course of the concentration changes in nucleosides when a solution of 100 μM each of dCyd, dGuo, dThd, and dAdo with 5 mM Trolox in 100 mM potassium phosphate buffer at pH 7.4 was irradiated with UV light through a 300-nm longpass filter for 0–10 min at a temperature of 37°C. dCyd (closed circles), dGuo (closed triangles), dThd (closed squares), dAdo (closed rhombi), 5S-DHdThd (Product 1) (open circles), and 5R-DHdThd (Product 2) (open triangles). All the reaction mixtures were analyzed by RP-HPLC. Means ± standard deviation (S.D.) (n = 3) are presented