A cyanobacterium, Synechococcus sp. PCC 7942 was transformed with a re
combinant plasmid harboring poly-(hydroxybutyrate) (PHB)-synthesizing
genes from Alcaligenes eutrophus. The acquired transformant accumulate
d about 1% PHB of dry cell weight in nitrogen-starved conditions. The
PHB content of the transformant was kept stable during a series of bat
ch cultures.