Microcystis aeruginosa

In the Slimmer of 1989, Rutland Water, the largest man-made lake in Western Europe and which supplies potable water to approximately 500 000 people in the East of England, contained a heavy bloom of Microcystis aeruginosa. By the end of the summer, a number of sheep and dogs had died after drinking from the bloom and concentrated scum. Analysis revealed that the cyanobacterial bloom material was toxic to laboratory mice, and that rumen contents from a poisoned sheep contained fivemicrocystin variants.Microcystins were detected in waters used for recreation in Australia at concentrations greater than 1 mg per... 

Lehman PW, Boyer G, Waller C, Gehrts K (2005) Distribution and toxicity of a colonial Microcystis aeruginosa bloom in the San Erancisco Bay Estuary. Hydrobiologia 541 87-99... 

Figure 8. Left The cyclic heptapeptide hepatotoxin microcystin-LA (cyanoginosin-LA) produced by the colonial cyanobacterium Microcystis aeruginosa strain WR-70 (UV-010). MW = 909. Right The cyclic heptapeptide hepatotoxin microcystin-LR (cyanoginosin-LR) produced by a waterbloom of the colonial cyanobacterium Microcystis aeruginosa collected in Lake Akersvatn, Norway, 1984-85 MW=994, 69J1).

HSCCC was successfully applied for the first time to the isolation and purification of zeaxanthin from cyanobacterium Microcystis aeruginosa. Adducts of flavonols and anthocyans were also isolated using this method. ... 

Chen, F. et al.. Isolation and purification of the bioactive carotenoid zeaxanthin from the microalga Microcystis aeruginosa by high-speed counter-current chromatography, J. Chromatogr, 1064, 183, 2005. 

Walsh, K., G. J. Jones et al. (1998). Effects of high irradiance and iron concentration on pigment and fatty acid composition in the cyanobacterium Microcystis aeruginosa. Mar. Freshwater Res. 49(5) 399 107. 

In our previous research, we found that the antialgal allelochemical Ethyl 2-Methylacetoacetate (EMA) caused loss of cell membrane integrity. It hinted that EMA may cause a change in the membrane. It is reported that environmental stress may increase the concentration of ROS in plant cell. The excessive ROS may cause a decrease of antioxidation enzymes activity and lipid peroxidation. The effect of EMA on the activity of SOD and POD and lipid fatty acids of Chlorella pyrenoidosa, Chlorella vulagaris and Microcystis aeruginosa were evaluated to elucidate the mode of action of EMA. 

Zheng XH, Xiao L, Ren J, Yang LY (2008) The effect of a Microcystis aeruginosa bloom on the bacterioplankton community composition of Lake Xuanwu. J Freshwater Ecol 23 297-304... 

Rapid-acting cytotoxin that disrupts cell membranes in the liver (hepatoxin) causing an accumulation of blood in the liver. It is the most toxic of the Microcystins. It is a solid obtained from freshwater blue-green cyanobacteria (Microcystis aeruginosa, Microcystis cyanea). It is heat stable and water soluble. Aqueous solutions are "probably stable" and resistant to chlorine at 100 ppm. It is also soluble in alcohol and acetone. 

Fulton III RS, Paerl HW (1987) Toxic and inhibitory effects of the blue-green alga Microcystis aeruginosa on herbivorous zooplankton. J. Plankton Res 9 837-855 Gilbert JJ (1990) Differential effects of Anabaena afflnis on cladocerans and rotifers mechanisms and implications. Ecology 71 1727-1740... 

APHA Selenastrum capricornutum, Species-dependent Microcystis aeruginosa, between 103 and Anabaena flos-aquae, 50 X 103 Cyclotella sp. Nitzschia sp. Synedra sp. APHAb Growth rate 24 2 32-65 pmol m 2 s 1... 

Cyanobacteria -Microcystis aeruginosa Micropeptins 478-A and -B -peptide-based plasmin inhibitors Cyanopeptolins A-D -protease inhibitors Cyanopeptolin 963A-chymotrypsin inhibitor 120 6, 262 263... 

Cyanobacteria -Microcystis aeruginosa Aeruginosins 298-A and -B -thrombin and trypsin inhibitors 266-269... 

HO3SO H Cyanobacteria -Microcystis aeruginosa Aeruginosins 98-A, 98-B, 98-C, and 101 - trypsin inhibitors 266, 269, 273... 

Kociba, R.J., Schwetz, B.A., Keyes, D.G., Jersey, G.C., Ballard, J.J., Dittenber, D.A., Quasi, J.F., Wade, C.E., and Humiston, C.G. Chronic toxicity and reproduction studies of hexachlroobutadieneinrats. Environ. Health Perspect., 21 49-53, 1977. Koelmans, A.A., van der Woude, H., Hattink, J., and Niesten, DJ.M. Long-term bioconcentration kinetics of hydrophobic chemicah in Selenastrum capricornutum and Microcystis aeruginosa. Environ. Toxicol. Chem., 18(6) 1164-1172, 1999. 

Newman JR, Barrett PRF, Control of Microcystis aeruginosa by decomposing barley straw, JAquat Plant Manage 31 203—206, 1993. 

Peptide toxins. Of all the toxins produced by freshwater cyanobacteria, the peptide toxins of Microcystis aeruginosa have received the most attention. All research on these peptide toxins indicates they are small, possibly cyclic, with molecular weights estimated at 1200 to 2600 (10,11). Recent work has become more definitive in the estimation of molecular weight and amino acid composition. In 1978 Elleman et al. (12) reported that they had isolated and characterized the peptide toxin of an Australian strain Microcystis which was a pentapeptide with a minimum molecular weight of 654. It consisted of equimolar amounts of alanine, tyrosine, methionine, glutamic and 3-methyl aspartic acid and methylamine. 

Three different toxins have been associated with Microcystis aeruginosa. The most common of these is a fast death factor (FDF,... 

Toxins oi Microcystis aeruginosa and Their Hematological and Histopathological Effects... 

The cosmopolitan cyanobacterium Microcystis aeruginosa is frequently the major component of freshwater cyanobacterial blooms. These blooms can cause serious water management problems and are occasionally associated with animal poisoning. The aeruginosa toxins are potent lethal peptides which contain three invariant D-amino acids (Ala, erythro-3-methyl Asp, and Glu), two variant L-amino acids, N-methyl dehydroalanine, and a 3 amino acid (1-3). Multiple toxins have been purified from clonal isolates (1,4). The toxic peptide described in this chapter is denoted toxin-LR using the standard one-letter abbreviations for its two variant amino acids, leucine and arginine. 

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