Figure 5.

Effects of the addition of different solutes to a preestablished H⁺ gradient measured by the fluorescence quenching of the pH-sensitive probe ACMA in tonoplast vesicles isolated from C. roseus leaves and grape cell cultures. A, Addition of different solutes to energized C. roseus tonoplast vesicles: 0.03 mm AVLB (a), 1 mm vindoline (b), and 0.075 mm catharanthine (c) from C. roseus; 1 mm atropine (d) from Atropa belladonna; 0.05 mm ajmaline (e) from Rauwolfia serpentina; 0.1 mm papaverine (f) from Papaver somniferum; and 0.15 mm CaCl₂ (g). B, Addition of 1 mm vindoline to energized grape tonoplast vesicles.