BACKGROUND The cyanobacterium Microcystis aeruginosa is one of the principal bloom-forming cyanobacteria present in a wide range of freshwater ecosystems. M. aeruginosa produces cyanotoxins, which can harm human and animal health. Many metabolic pathways in M. aeruginosa, including photosynthesis and microcystin synthesis, are controlled by its circadian rhythms. However, whether xenobiotics af...

Cyanobacteria are capable of thriving in almost all environments. Recent changes in climatic conditions due to increased human activities favor the occurrence and severity of harmful cyanobacterial bloom all over the world. Knowledge of the regulation of cyanotoxins by the various environmental factors is essential for effective management of toxic cyanobacterial bloom. In recent years, progres...

The diversity of microcystin-producing cyanobacteria in the western basin of Lake Erie was studied using sequence analysis of mcyA gene fragments. Distinct populations of potentially toxic Microcystis and Planktothrix were found in spatially isolated locations. This study highlights previously undocumented diversity of potentially toxic cyanobacteria.

BACKGROUND/AIM Cyanobacterial toxins befall a group of various compounds according to chemical structure and health effects on people and animals. The most significant in this large group of compounds are microcystins. Their presence in water used for human consumption causes serious health problems, liver beeing the target organ. Microcystins are spread all over the world. Waterblooms of cyano...

Due to the stratospheric ozone depletion, several organisms will become exposed to increased biologically active UVB (280-320 nm) radiation, not only at polar but also at temperate and tropical latitudes. Bloom forming cyanobacteria are exposed to UVB radiation on a mass scale, particularly during the surface bloom and scum formation that can persist for long periods of time. All buoyant specie...

Microcystis aeruginosa is a typical algal bloom-forming cyanobacterium. This report describes the whole-genome sequence of a non-microcystin-producing strain of Microcystis aeruginosa, NIES-44, which was isolated from a Japanese lake.

The hypothesis that negative effects of Microcystis on Daphnia growth and reproduction can be explained from the presence of microcystin in the Microcystis cells was tested by comparing the effects on Daphnia life history characteristics of a microcystin-free mutant strain and microcystin-containing strain of the cyanobacterium Microcystis aeruginosa PCC7806. To avoid nutritional deficiency, Mi...

This is the first report on microcystins, cyclic heptapeptide hepatotoxins, from Brazilian water supplies. A colony isolate (NPJB-l) of the colonial cyanobacterium Microcystis aeruginosa from Lagoa das Gan;as, Sao Paulo, was cultured under non-axenic conditions. Exponential phase cells were harvested, concentrated and lyophilized for mouse bioassays and toxin extraction. The LDlOO oflyophilized...

Cyanobacterial harmful algal blooms (cyanoHABs) have been observed across the USA and worldwide, even locally in Lake Fayetteville (Arkansas, USA) once we started monitoring for total microcystin. The goal of this research note was to present a framework that might help guide cyanoHAB toxin public health advisories at Fayetteville. We evaluated nonparametric change points (i.e., thresholds) hie...

In this work, the performances of two electrochemical cells, a conventional liquid-electrolyte electrolyzer (LEE) and solid-electrolyte (SEE) were compared for treatment real water matrixes polluted with microcystin-LR at trace concentrations. The first consists single-compartment flow cell, while second membrane-electrode assembly cell. Both cells can attain removal microcystin, although toxin...