Abstract Background Microcystins are emerging marine biotoxins, produced by potentially toxic cyanobacteria. Their presence has been reported in aquatic animals Greek freshwater, while data few environments. Since the climate change induces eutrophication and harmful algal blooms coastal ecosystems affecting public health, further research on microcystins’ waters is required. The aim of this st...

The present study was aimed to investigate the effects of microcystin–LR (MCLR) on the blood electrolytes of Heteropneustes fossilis. The fish were injected microcystinLR (2.5 μg/25 g) intraperitoneally at the initiation of the experiment. Blood samples were collected and the serum calcium and phosphate levels were estimated at 1, 3, 5, 10, 15 days. There is no change in serum calcium level of ...

The evolution of the microcystin toxin gene cluster in phylogenetically distant cyanobacteria has been attributed to recombination, inactivation, and deletion events, although gene transfer may also be involved. Since the microcystin-producing Microcystis aeruginosa PCC 7806 is naturally transformable, we have initiated the characterization of its type IV pilus system, involved in DNA uptake in...

Oregon surface waters are experiencing increased occurrence of potentially toxic cyanobacterial blooms (Fig. 1). It is necessary to use the modifier “potentially” because there is no toxin monitoring in the state of Oregon. Advisories are currently based on cell counts of potentially harmful cyanobacteria. This summary is intended to briefly review the recent research on the effects of a cyanob...

The eutrophic process potentially caused by a high urine and faecal load resulting from an unusually high hippopotamus (Hippopotamus amphibious) density in the Nhlanganzwane Dam, Kruger National Park, South Africa, triggered a chain of events characterised by an increase in the growth of primary producers (Microcystis aeruginosa). This increase in M. aeruginosa biomass was followed by bio-intox...

In this study we investigated the presence of toxin-producing cyanobacterial contaminants in food supplements manufactured from blooms of the non-toxic freshwater cyanobacterium Aphanizomenon flos-aquae. Previous reports investigating the contamination of health food supplements with toxin-producing cyanobacteria have used chemical and or biochemical methods such as HPLC, ELISA and protein phos...

This study was carried out in order to investigate the spatial variation of algal toxin (microcystin) concentrations along the shoreline of Lake Victoria. A total of 16 nearshore stations differing in connectivity to the main lake basin were categorized as either closed bays (ratio of bay area to bay opening < 1) or open bays (ratio ≥ 1) and sampled during November and December 2009. Water samp...

Toxic cyanobacteria such as Microcystis aeruginosa are a worldwide concern in freshwater reservoirs. Problems associated with their mass occurrence are predicted to increase in the future due to global warming. The hepatotoxic secondary metabolite microcystin is of particular concern in this context. This study aimed to determine whether co-occurring microorganisms influence the expression of m...

Purified preparations of a distinct autophosphorylation-activated protein kinase from bovine kidney phosphorylated and inactivated purified preparations of protein phosphatase 2A2 (PP2A2) by about 80% with the autophosphorylation-activated protein kinase, protamine kinase, and 32P-labeled myelin basic protein as substrates. Analysis of incubations performed in the presence of 0.2 mM [gamma-32P]...

Cyanobacteria are the predominant phototrophs in freshwater ecosystems of the polar regions where they commonly form extensive benthic mats. Despite their major biological role in these ecosystems, little attention has been paid to their physiology and biochemistry. An important feature of cyanobacteria from the temperate and tropical regions is the production of a large variety of toxic second...