Toxic flagelates

Surprisingly, most of the definitive cell biology on toxic dino-flagellates has yet to be observed, understood and described. What was once thought to be the major causative genus, Gonyaulax, is now known to contain a wide variety of similar strains/ varieties/species ( ). ... 

Several papers dealt with toxic dinoflagellate taxonomy at the Second International Conference on Toxic Dino flagellate Blooms ( l)and this paper summarises developments since then. A paper by Steidinger ( 2), which appeared after the ACS symposium from which the present papers arise, also discusses this topic and this paper has been revised to reduce duplication. Her paper should be consulted for greater illus-... 

Norris, L. Chew, K. K. Proc. 1st Intnl. Conf. Toxic Dino-flagellates, Mass. Science Tech. Found., Wakefield, Massachusetts. 1975, p. 143-152. 

Table III. Results From Initial Screening of Nine Species of Dino-flagellates for Toxicity. Doses of 5 or 10 mg (when available) Were Injected (ip) Into Two or Four 20 g mice. Fractions Were Recorded as Toxic (T) if They Caused Death Within 48 Hours. Fractions Causing Characteristic Symptoms but Not Death Were Recorded...

Roseth, S., Edvardsson, T., Botten, T.M., Fuglestad, J., Fonnum, F. and Stenersen, J. (1996) Comparison of acute toxicity of process chemicals used in the oil refinery industry, tested with the diatom Chaetoceros gracilis, the flagellate Isochrysis galbana, and the zebra fish, Brachydanio rerio, Environmental Toxicology and Chemistry 15 (7), 1211-1217. 

A probable explanation of this is that the water was full of microscopic organisms known as dino flagellates (phytoplankton), which impart a red colour to the sea or river and are the cause of the so-called red tides . A more recent example was the red tide that occurred in the Gulf of Mexico in 1946 which resulted in the death of large numbers of fish. The dino-flagellates, which may be eaten by shellfish, produce highly toxic brevetox-ins. If the shellfish are then eaten by humans serious poisoning may result. 

Saxitoxin is a naturally occurring substance in dino-flagellates and taken up by shellfish. Consumption of the shellfish leads to toxicity. Aside from the knowledge that these organisms serve as a source of exposure, the environmental fate of the chemical... 

S. Wiegman, P.L.A. van Vlaardingen, E.A.J. Bleeker, P. de Voogt, M.H.S. Kraak (2001). Photoenhnaced toxicity of azaarene isomers to the marine flagellate Dunaliella tertiolecta. Environ. Toxicol. Chem., 20,1544-1550. 

Neurotoxin found in soft coral and believed to be produced by a flagellate and concentrated by the coral (Palythoa toxica). Most deadly non-protein toxin known LD50 (mice) 0.15 pg/kg. 20-50 times as toxic as tetrodotoxin. Intense vasoconstrictor 0.06 pg/kg IV in dogs produced a transient rise in blood pressure followed by rapid hypotension and death within 5 min. 

Most other non-silicified small flagellates -Euglenozoa, Heterokonts (Bicoesida, Am, H 40 - 1 + 12 1 phagotrophy, some parsitism (in fungal types), some toxicity... 

Nakahara, H., Sakami, T., Chinain, M. and Ishida, Y. The role of macro-algae in epiphytism of the toxic dino-flagellate Gambierdiscus toxicus (Dinophyceae), Phycol. Res., 44, 113-117, 1996. 

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