Planktothrix

Cyanobacteria -/Anafaaena spp. and Oscillatoria sp. (Planktothrix spp.) Cyanobacteria - Planktothrix spp. 

Anatoxin-a is a naturally occurring homotropane alkaloid produced by freshwater cyanobacteria of the genera Anabama (A. flos-ctquae and A. circinalis), Aphanizome-non, Cylindrospermum, Planktothrix, Microcystis aeruginosa [5-7], and Phormidium favosum [8]. Fatal intoxications have typically included cattle and birds [9], and, more recently, dogs [8] and flamingos [10]. 

Homoanatoxin-a, obtained from various freshwater cyanobacteria, is a relatively rare natural analog of anatoxin-a for which the C-11 side chain is extended by one methylene unit (Figure 6.4). It was originally isolated from Planktothrix sp. (formerly Oscillatoria) in 1992 [51]. It has recently been isolated from Raphidiopsis mediterranea Skuja from Japan [52] and Planktothrix (formerly Oscillatoria) formosa blooms in Ireland [53]. 

In 1992, a methylene analogue of AN, named homoanatoxin-a (HMAN), was isolated from Planktothrix (Oscillatoria) formosa in Norway (Skulberg et al. 1992). Interestingly, HMAN... 

Ireland Anabaena, Planktothrix AN Dogs James etal. 1997... 

In Scotland, during 1981-1982, cyanobacteria from several lakes were found to be toxic by mouse bioassay (i.p.) (Richard et al. 1983), but the first case of AN intoxication due to benthic cyanobacteria was reported 10 years later (Edwards et al. 1992). The neurotoxic bloom consisted mainly of Planktothrix species and was associated with three canine fatalities AN was identified in the stomach contents of one of the dogs (Gunn et al. 1992). In Finland, the first survey of cyanobacterial blooms during 1985-1987 revealed that 13 out of 30 bloom samples contained AN (Sivonen etal. 1989). Toxin content was in the range 12 360 pg AN/g lyophilized material. During this... 

In Japan, the first detection of AN and its degradation product, epoxy-AN, have been reported (Park et al. 1993). This was also the first study to show that Microcystis could produce both AN and microcystins. The predominant species were Anabanea and Planktothrix with toxin concentrations in the range 0.4-16 pg AN/g. In addition, AN, HMAN, and a new compound, hydroxy-HMAN, were isolated from Raphidiopsis mediterranea in Japan (Namikoshi et al. 2003 Watanabe et al. 2003). AN was also found in four of 26 samples from Korean lakes, collected during 1992-1995 (Park etal. 1998). 

Viaggiu, E., Melchiorre, S., Volpi, E, Di Corcia, A., Mancini, R., Garibaldi, L., Crichigno, G., and Bruno, M. 2004. Anatoxin-A toxin in the cyanobacterium Planktothrix rubescens from a fishing pond in northern Italy. Environ Toxicol 19, 191-197. 

Microcystins and Nodularins Mieroeystins (MC) are widely distributed eyanotoxins, and have often been implicated in aeeidental human and animal poisonings. They are produeed by several genera, including the planktonic Microcystis, Planktothrix, Anabaena species, and the benthic Oscillatoria. Nodularins are only produced by the species Nodularia spumigena, whieh occurs in brackish waters, essentially in the Baltie Sea, Australia, and New Zealand. 

Anatoxins are produced mainly by Anabaena species, but also by Aphanizomenon, Planktothrix, Cylindrospermum, Microcystis, and the benthic Oscillatoria and Phormidium (Sivonen and Jones, 1999). 

Briand, E., Gugger, M., Frangois, J.C., Bernard, C., Humbert, J.F., Quiblier, C. (2008). Temporal variations in the dynamics of potentially microcystin-producing strains in a bloom-forming Planktothrix agardhii (cyanobacteria) population. Appl. Environ. Microbiol. 74 3839 8. 

Pomati, F., Sacchi, S., Rossetti, C., Giovannardi, S., Onodera, H., Oshima, Y., Neilan, B.A. (2000). The freshwater cyanobacterium Planktothrix sp. FPl molecular identification and detection of paral 4ic shellfish poisoning toxins. J. Phycol. 36 553-62. 

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