Algae toxins

Blue-Green Algae Toxin Blue-Green Algae Toxin Bluetongue... 

MOORE Marine Blue-Green Algae Toxins... 

Puschner, B., Humbert, J.F. (2007). Cyanobacterial (blue-green algae) toxins. In Veterinary Toxicology Basic and Clinical Principles (R.C. Gupta, ed.), pp. 714-25. Academic/Elsevier Press, London. 

Tetrodotoxin (from puffer fish) and saxitoxin (algae toxin, "red tide")... 

Pietsch, I, et al. (2001) Analytical determination of algae toxins (hepato- and neurotoxins) by HPLC/MS/MS. Biologische Abwasserreinigung, 16,35-50. 

Solomon AE, Stoughton RB (1978) Dermatitis from purified sea algae toxin (Debromoaplysiatoxin). Arch Dermatol 114 1333... 

Natural Toxins from Cyanobacteria (Blue-Green Algae)... 

Algal blooms in fresh water ponds occasionally poison livestock and waterfowl. Axenic cultures of Anabaena flos-aquae NRC 44-1 were shown to produce the toxic principle (5) which can be present in the algae and in the water of mature cultures (6). The discovery of the toxin was fortuitous in the sense that AChR agonists do not have a (known) constructive function in the algae evolution of the synthetic pathway was likely a by-product of metabolic pathways in the algae. The compound became evident only through its toxic effects on other organisms. 

Hellio, G.B., Bremer A.M., Pons, G., Cottenceau, Y. and Le Gal, N. (2000). Antibacterial and antifungal activities of extracts of marine algae from Brittany France. Use as antifouling agents. Applied Microbiology Biotechnology 54 543-549. Hsu, S.B. and Waltman, P. (1998). Competition in the chemostat when one competitor produces a toxin. Japan Journal of Industrial and Applied Mathematics 15 471-490. 

The commercial availability of certain toxin standards has allowed researchers to examine the physiological mechanisms of allelopathy by cyanobacteria. The best known examples are from studies on microcystins, which affect plants and aquatic algae by interfering with protein phosphatases in a manner similar to their effect on vertebrate enzymes (Babica et al. 2006). However, there is evidence that microcystins can also promote the formation of reactive oxygen species (ROS) in photoautotrophs, which can cause extensive damage to cellular membranes and enzymes (Babica et al. 2006 Leflaive and Ten-Hage 2007). 

One role of cyanobacterial allelochemicals may be to alter the motility and distribution of competing photoautotrophs. In a recent study, Kearns and Hunter (2001) examined the effects of toxic metabolites from the filamentous cyanobacterium A. flos-aquae on a unicellular phytoplankton species, Chlamydomonas rein-hardtii. A. flos-aquae synthesizes both microcystins as well as anatoxins, providing the authors with an ecologically relevant opportunity to assess the individual and combinatorial effects of these toxins on an alga. 

Cells of C. reinhardtii were exposed to cell-free filtrates from A. flos-aquae, pure microcystin-LR or anatoxin-a, or combinations of the toxins. Both the position of the cells and the chlorophyll-a concentration of the cultures were observed for 12 days. Exposure to crude extracts as well as to combinations of the toxins significantly decreased chlorophyll levels in the cultures. Furthermore, these compounds were all capable of paralyzing the algae and thus promoted the settlement of C. reinhardtii cells. One intriguing aspect of this dynamic interaction is the separate finding that C. reinhardtii may actually induce toxin synthesis in A. flos-aquae (Kearns and Hunter 2000), essentially signaling its own demise. 

Temporal and spatial shifts in the abundance of chemically undefended algae and cyanobacteria may leave grazers with few dietary options except to consume low-quality, chemically defended food items. While some herbivores may be able to either tolerate or inactivate these toxins (Samelle and Wilson 2005), species that lack tolerance may be faced with the dilemma of either remaining on a low-quality patch or migrating to a different patch, thus increasing their risk of predation by visual predators (Krivan and Vrkoc 2000). In systems that experience seasonal... 

Sheath RG (2003) Red Algae. In Wehr JD, Sheath RG (eds) Freshwater algae of North America ecology and classification. Academic, San Diego, CA, pp 197-224 Sivonen K, Jones G (1999) Cyanobacterial toxins. In Chorus I, Bartram J (eds) Toxic cyanobacteria in water a guide to their public health consequences, monitoring and management. WHO, E FN Spon, London, pp 41-111... 

Disch A, Schwender J, Muller C, Lichtenthaler HK, Rohmer M (1998) Distribution of the meval-onate and glyceraldehyde phosphate/pyruvate pathways for isoprenoid biosynthesis in unicellular algae and the cyanobacterium Synechocystis PCC 6714. Biochem J 333 381-388 Dittmann E, Wiegand C (2006) Cyanobacterial toxins - occurrence, biosynthesis and impact on human affairs. Mol Nutr Food Res 50 7-17... 

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