Total carbohydrates (Total CH) (A), capsular polysaccharides (CPS) (B), and released polysaccharides (RPS) (C) of Synechocystis sp. PCC 6803 wild-type (wt) and kpsM mutant strains, expressed as milligrams of carbohydrates per liter of culture. Cells were grown in BG11 medium at 30°C under a 12-h light (50 μE m−2 s−1)/12-h dark regimen, with orbital shaking at 150 rpm. Experiments were performed in triplicate, and statistical analysis is presented for the last time point (***, P value of ≤0.001).