Liver mass (hepatosomatic index, HSI) increased by approximately 18% and water content in the gut by approximately 13 ml kg(-1) in freshwater rainbow trout exposed for 24 h to intact cells of a microcystin-producing cyanobacterium (Microcystis PCC 7813) together with administration of heterotrophic bacterial LPS. Exposure to broken (ultrasonicated) cyanobacterial cells together with administrat...

Microcystis Kützing ex Lemmermann is among the genera of cyanobacteria often associated to toxic blooms with the release of microcystins. A gene cluster codes for microcystin synthetases, which are involved in the biosynthesis of this toxin. The aim of the present study was to investigate the genetic diversity of the mcyB gene, specifically the B1 module, in Brazilian strains of Microcystis spp...

Cyanobacteria (blue-green algae) (e.g., Microcystis and Nodularia spp.) capable of producing toxic peptides are found in fresh and brackish water worldwide. These toxins include the microcystin (MC) heptapeptides (>60 congeners) and the nodularin pentapeptides (ca. 5 congeners). Cyanobacterial cyclic peptide toxins are harmful to man, other mammals, birds, and fish. Acute exposure to high conce...

Toxic cyanobacterial blooms are an increasing problem in the lower Laurentian Great Lakes. To better understand their occurrence and distribution, samples for particulate toxin analysis were collected from more than 140 New York Lakes including Lakes Erie, Champlain and Ontario. Microcystins were of most importance and were detected in nearly 50% of the samples. Anatoxin-a, cylindrospermopsin a...

Cyanobacteria (blue-green algae), Microcystis aeruginosa sp., were isolated from a massive bloom in a eutrophic waterbody in Hungary. Their toxic effect, determined by a mouse test, was associated with the occurrence of microcystins YR and LR which were isolated, separated by means of HPLC procedures and identified by mass spectroscopy. The toxin content of the dry cell material is about 0.22 %...