Uptake hydrogenase mutant cells of the cyanobacterium Nostoc sp. PCC 7422 photobiologically produced H2 catalyzed by nitrogenase for several days in H2-barrier transparent plastic bags, and accumulated H2 in the presence of O2 evolved by photosynthesis. Their H2 production activity was higher in the sealed flexible bags than in stoppered serum bottles of fixed gas volume.
