Figure 8.
The effect of MgCl2 concentration on the PSII/PSI ratio in thylakoid membranes of C. reinhardtii and Clamydomonas sp. UWO241 is shown. Thylakoid membranes were isolated in buffer (0.3 m sorbitol and 50 mm tricine, pH 7.8), containing varying concentrations of MgCl2: 0, 1, 5, and 10 mm. Membranes were treated in the dark at 5°C and immediately frozen in liquid nitrogen. The PSII/PSI ratio is represented by the ratio between the areas of PSII related peaks (λ1, λ2, λ3) and the area of the PSI peak (λ4), as calculated from 77K chlorophyll fluorescence traces. All data represent the means of three individual experiments.