Fig. 6.

Effects of aas deficiency and farB expression on the PSII activity (A) and the sensitivity of PSII to photoinhibition (B) in Synechocystis sp. PCC 6803. (A) PSII activity of the WT, dAS11 and dAS11_farB cells grown under LL conditions (50 µmol photons m⁻² s⁻¹) for 24 h. The letters denote significant differences (P < 0.01, Tukey’s test). (B) Susceptibility of the WT (filled circles), dAS11 (open circles) and dAS11_farB (open triangle) cells to photoinhibition. The LL-grown cells were incubated under 1500 µmol photons m⁻² s⁻¹ light conditions for 60 min in the absence or presence of 200 µg ml⁻¹ lincomycin and the PSII activity was measured at the indicated time points. One hundred percent activity for each of the strains was in the range shown in (A). Data shown are mean ± SE (bars) from three independent experiments. Asterisks indicate significant differences compared with WT (P < 0.01, t-test).