Figure 2.

Effects of light and lincomycin on the NaCl-induced inactivation of the oxygen-evolving machinery. Wild-type (A) and desA⁻/desD⁻ (B) cells were incubated with 1.0 M NaCl in darkness or in light at 50 μE⋅m⁻²⋅s⁻¹ in the absence or presence of 25 μg/ml lincomycin. At designated times, a portion of the cell suspension was withdrawn and the oxygen-evolving activity was measured at 35°C after addition of 1.0 mM BQ. The activities of wild-type and desA⁻/desD⁻ cells that corresponded to 100% were 590 ± 22 and 532 ± 16 μmol of O₂ per mg of Chl per h, respectively. ○, Light in the absence of lincomycin; ▵, light in the presence of lincomycin; ●, darkness in the absence of lincomycin; and ▴, darkness in the presence of lincomycin. Each point represents the average of results from four independent experiments.