No abstract

A unialgal culture of Microcystis aeruginosa Kütz. emend. Elenkin, which is toxic when injected intraperitoneally into white mice, has been isolated. It produces a complex of symptoms similar to those which have been described for a number of toxic waterblooms. Two distinct factors seem to be present. One causes death in 4 to 48 hours preceded by symptoms of piloerection and dyspnea. It is detected only with freshly harvested cells. The other causes death within 2 to 3 hours preceded by pallor and convulsions. This second factor is an endotoxin which is detected only when cells become leaky or disintegrate. The presence of the slow-death factor tends to be obscured by the release of the fast-death factor. The concentration of the fast-death factor in the cells varies with the developmental stage of a culture and at maximum can be just as high as that of a very toxic waterbloom.

A toxic alkaloid, anatoxin-a, has been isolated from mass cultures of a unialgal clone, NRC-44h, of the freshwater blue-green algae Anabaena flos-aquae (Lyngb.) de Bréb., and its structure determined.

No abstract

Calves, rats, ducks, and goldfish given lethal oral doses of bacteria-free lyophilized cell suspensions of toxic Anabaena flos-aquae died as a result of respiratory arrest. Experiments with selected animals and pharmacological preparations showed that the main effect of the toxin was production of a sustained postsynaptic depolarizing neuromuscular blockade.