Photosynthetic properties of UWO 241 under various light intensities using ECS. A to C, The ECS_t (proportional to pmf; A), g_H+ (reflecting ATP synthase activity; B), and ν_H+ (reflecting proton flux through ATP synthase; C) of UWO 241 grown in LS (black squares) and HS (gray circles) conditions were measured from dark interval relaxation kinetics. D, The relationship between ν_H+ and LEF (measured by chlorophyll fluorescence; Supplemental Fig. S2) was assessed in UWO 241. Data are means ± sd (n = 3). Asterisks indicate statistical differences (Student's t test, unequal variance; *P< 0.05).