The main goal of the present work is to test the hypothesis that small-scale turbulence affected physiological activities and the morphology of cyanobacteria in high turbulence environments. Using quantified turbulence in a stirring device, we conducted one set of experiments on cultures of two strains of cyanobacteria with different phenotypes; i.e., unicellular Microcystis flos-aquae and colo...

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...

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...

The effects of monosulfuron on growth and photosynthetic pigments of the nitrogen-fixing cyanobacterium Anabaena flos-aquae grown exposed to 2000-, 3000-, and 4000-lux light intensity were studied. Exposed to three light intensities, the seven concentrations of monosulfuron tested can significantly inhibit algal growth in a dose-dependent manner. The cell numbers and growth rate were decreased ...

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 cyanobac...

Aphanizomenon flos-aquae is a toxic filamentous cyanobacterium that causes water blooms in freshwaters across the globe. We present the draft genome sequence of the A. flos-aquae strain NIES-81, which was determined by 454 pyrosequencing technology. The draft genome is ~5.7 Mb, containing 5,802 predicted protein-coding genes and 58 RNA genes, with a G+C content of 38.5%.