On the presence of peptide synthetase and polyketide synthase genes in thecyanobacterial genus Nodularia

Nodularin is a hepatotoxin produced by the bloom-forming cyanobacterial spe cies Nodularia spumigena. Putative peptide synthetase and polyketide syntha se genes were detected in toxic strains of Nodularia by degenerate PCR. Usi ng specific primer sets, peptide synthetase and polykelide synthase gene ho mologues were detected in nodularin-producing strains indicating a possible role of peptide synthetase and polyketide synthase enzyme complexes in the biosynthesis of nodularin. Strains of Nodularia isolated from around the w orld were also analyzed for the production of nodularin by the protein phos phatase 2A inhibition assay. The protein phosphatase inhibition assay and t he molecular detection of peptide synthetase and polykelide synthase genes in Nodularia may be useful techniques for the assessment of nodularin-produ cing cyanobacteria in the environment. (C) 2001 Federation of European Micr obiological Societies. Published by Elsevier Science B.V. All rights reserv ed.