Phenotypic characterization of Synechocystis sp. PCC 6803 substrains reveals differences in sensitivity to abiotic stress - Fig 3

Photosynthesis performance of Synechocystis substrains GT-L (white circles), GT-B (red triangles) and PCC-B (blue squares) evaluated by measurement of oxygen evolution (A, B, C, D) and fast pigment fluorescence kinetics (O-J-I-P-S-M; E, F, G, H). The cultures were adapted to 25 μmol(photons) m^-2 s^-1 of red and blue light (A, E), 220 μmol_photons m^-2 s^-1 of red light complemented with 25 μmol(photons) m^-2 s^-1 of blue light (B, F), 660 μmol(photons) m^-2 s^-1 of red complemented with 25 μmol(photons) m^-2 s^-1 of blue light (C, G) and 72 μmol_photons m^-2 s^-1 of red light complemented with 526 μmol(photons) m^-2 s^-1 of white light (D, H). The cells were cultivated at 32°C under input CO₂ concentration of 5 000 ppm in a quasi-continuous regime as described in the main text. The cells were darkened for 15 minutes prior to fluorescence measurement. Each point represents average from at least four independent experiments, the error bars represent standard errors. The pigment fluorescence curves are visualized without error bars for better clarity. The dashed lines in panels A–D represent fitting of the data points by the function derived by Platt et al. (1980) [51].