Fig 2: PsbA plotted versus PsbD, both in fmoles µg protein-1 as determined by quantitative immunoblotting.MIT 9313 grown at 30 µmol photons m-2 s-1 (pale blue squares); MIT 9313 grown at 90 µmol photons m-2 s-1 (dark blue squares); MED 4 grown at 30 µmol photons m-2 s-1 (pale green triangles); MED 4 grown at 260 µmol photons m-2 s-1 (dark green triangles); WH 8102 grown at 30 µmol photons m-2 s-1 (light red circles); WH 8102 grown at 260 µmol photons m-2 s-1 (dark red circles).

Fig 3: Protein levels of GPX5 in WT-4A and GPX5-overexpressor (GPXHOX) mutants under LL and in response to HL, ß-cyclocitral and acrolein. (A) Three GPXHOX lines and WT-4A were analysed for GPX5 protein levels under LL. Shown above is the Ponceau-stained membrane for loading control. (B) The effect of LL, 4 h with HL, and 4 h with 600 ppm of ß-cyclocitral (ß-cc) or with 600 ppm of acrolein (4 h Acro.) under LL, on GPX5 levels. The D1 reaction centre of photosystem II (PsbA) was used for loading control.

Fig 4: Fe deficiency effect on Arabidopsis thaliana rosette leaves photosynthetic activity is less pronounced when S availability is scarce.(A-C) Western blot analyses using total protein extracts from whole rosette leaves of Arabidopsis plants grown for three weeks in presence of 25 µM Fe(III)-EDTA and then transferred for 10 days in four different media: control (+Fe +S), S deficiency (+Fe -S), Fe deficiency (-Fe +S) and Fe and S deficiencies (-Fe -S). Three proteins related to the photosynthetic light reactions were analysed: (A) PsbA (photosystem II), (B) b6f (cytochrome b6f complex) and (C) PsaD (photosystem I). (D-E) Chlorophyll fluorescence parameters: (D) Fv/Fm of dark-adapted plants and (E) quantum yield of photochemical energy conversion. (A-E) Means with the same letter are not significantly different according to one-way ANOVA followed by post-hoc Tukey test (P< 0.05). n = 3 biological repeats from one representative experiment. Each experiment was repeated three times.

Fig 5: Chlorophyll allocations in Synechococcus (A) and Synechocystis (B) over a 120 hour iron depletion timecourse.Data were compiled from 6 (Synechococcus) or 5 (Synechocystis) replicate time course experiments. (A, B) Solid bars: IsiA subunit contents per µg of total cellular protein (Figure 1) were multiplied by 12 chlorophyll bound per IsiA monomer; Horizontal cross-hatching: PsaC subunit contents per µg of total cellular protein (Figure 1) were multiplied by 100 chlorophyll bound per PSI monomer; Diagonal cross-hatching: PsbA subunit contents per µg of total cellular protein (Figure 1) were multiplied by 36 per PSII monomer. Data presented are mean +/- standard error, n = 5 or 6.