| characterization of a microcystin and detection of microcystin synthetase genes from a brazilian isolate of nostoc. | a nostocalean nitrogen-fixing cyanobacterium isolated from an eutrophic freshwater reservoir located in piracicaba, são paulo, brazil, was evaluated for the production of hepatotoxic cyclic heptapeptides, microcystins. morphologically this new cyanobacterium strain appears closest to nostoc, however, in the phylogenetic analysis of 16s rrna gene it falls into a highly stable cluster distantly only related to the typical nostoc cluster. extracts of nostoc sp. cena88 cultured cells, investigated u ... | 2010 | 20003912 |