Glycolic acid oxidase activity was detected in cell-free preparations of Anabaena flos-aquae and Oscillatoria sp. by the reduction of 2,6-dichlorophenolindophenol and by the formation of glyoxylate. Enzyme activity was localized in the 20,000 times gravity supernatant fraction, and optimal activity was obtained at pH 8.0. Activity was lost on storing the preparation at 4 C and could not be rest...

Anabaena is a filamentous, N(2)-fixing, and morphologically diverse genus of cyanobacteria found in freshwater and brackish water environments worldwide. It contributes to the formation of toxic blooms in freshwater bodies through the production of a range of hepatotoxins or neurotoxins. In the Baltic Sea, Anabaena spp. form late summer blooms, together with Nodularia spumigena and Aphanizomeno...

Neurotoxic paralytic shellfish poisoning (PSP) toxins, anatoxin-a (ATX), and hepatotoxic cylindrospermopsin (CYN) have been detected in several lakes in northeast Germany during the last 2 decades. They are produced worldwide by members of the nostocalean genera Anabaena, Cylindrospermopsis, and Aphanizomenon. Although no additional sources of PSP toxins and ATX have been identified in German w...

The buoyancy organelles of aquatic microorganisms have to meet stringent specifications: allowing gases to equilibrate freely across the proteinaceous shell, preventing the condensation of water vapor inside the hollow cavity, and resisting collapse under hydrostatic pressures that vary with column depth. These properties are provided by the 7–8 kDa gas vesicle protein A (GvpA), repeats of whic...

The buoyancy organelles of aquatic microorganisms have to meet stringent specifications: allowing gases to equilibrate freely across the proteinaceous shell, preventing the condensation of water vapor inside the hollow cavity and resisting collapse under hydrostatic pressures that vary with column depth. These properties are provided by the 7- to 8-kDa gas vesicle protein A (GvpA), repeats of w...

This study involves a phytoplankton summer/autumn survey in 46 Virginia lakes and reservoirs during 2010-2012. A total of 307 taxa were identified which included several filamentous and colonial cyanabacteria in bloom concentrations.With the exception of one natural lake, the other sites sampled represent impoundments created decades ago, with the majority presently classified as mesoor eutroph...

The toxic effects of herbicides (Machete, Saturn) and pesticides (Diazinon and Malathion) on green algae, Scenedesmus obtusiusculus, and cyanobacteria, Anabaena flos aquae, were studied. The results indicated that Machete and Saturn, in comparison to Diazinon and Malathion, were more toxic. On the other hand it was revealed that green algae was more sensitive to the pesticides than the cyanoba...

Anabaena variabilis ATCC 29413 is a filamentous, heterocyst-forming cyanobacterium that has served as a model organism, with an extensive literature extending over 40 years. The strain has three distinct nitrogenases that function under different environmental conditions and is capable of photoautotrophic growth in the light and true heterotrophic growth in the dark using fructose as both carbo...

Gas vesicles are gas-filled buoyancy organelles with walls that consist almost exclusively of gas vesicle protein A (GvpA). Intact, collapsed gas vesicles from the cyanobacterium Anabaena flos-aquae were studied by solid-state NMR spectroscopy, and most of the GvpA sequence was assigned. Chemical shift analysis indicates a coil-α-β-β-α-coil peptide backbone, consistent with secondary-structure-...

Rhizoma Atractylodes macrocephala, Radix Isatidis, Coptis chinensis and Flos Genkwa are common herbal remedies used by pregnant woman in China. In this study, their potential embryotoxicity was assessed using the embryonic stem cell test (EST) and a prediction model. The potential embryotoxicity of the herbs was based on three endpoints: the concentrations of the compounds that inhibited the pr...