Photosynthesis and inorganic carbon uptake by spheroplasts isolated from the cyanobacterium Anabaena variabilis

Spheroplasts were prepared from the filamentous cyanobacterium Anabaena variabilis by lysozyme treatment followed by mild sonication. The rate of photosynthesis and the initial rate of accumulation of inorganic carbon within the spheroplasts were very close to those observed in intact cells. The steady-state intracellular inorganic carbon pool, however, was smaller in spheroplasts than in intact cells. It is suggested that the cell wall does not play an essential role in the process of HCO₃^- transport (leading to accumulation of inorganic carbon internally) but may have a significant impact on the diffusional dissipation of the intracellular pool of inorganic carbon.