Observation on Poterioochromonas sp. (Chrysophyte)

Quantitative Proteomics Reveals Ecophysiological Effects of Light and Silver Stress on the Mixotrophic Protist Poterioochromonas malhamensis

Aquatic environments are heavily impacted by human activities including climate warming and the introduction of xenobiotics. Due to the application of silver nanoparticles as bactericidal agent the introduction of silver into the environment strongly has increased during the past years. Silver ions affect the primary metabolism of algae, in particular photosynthesis. Mixotrophic algae are an in...

Scent of danger: floc formation by a freshwater bacterium is induced by supernatants from a predator-prey coculture.

We investigated predator-prey interactions in a model system consisting of the bacterivorous flagellate Poterioochromonas sp. strain DS and the freshwater bacterium Sphingobium sp. strain Z007. This bacterial strain tends to form a subpopulation of grazing-resistant microscopic flocs, presumably by aggregation. Enhanced formation of such flocs could be demonstrated in static batch culture exper...

Association of Formation and Release of Cyclic AMP with Glucose Depletion and Onset of Chlorophyll Synthesis in Poterioochromonas malhamensis.

Depletion of glucose from the culture medium by Poterioochromonas malhamensis results in cessation of growth and accumulation of cyclic adenosine 3':5'-monophosphate (cAMP), followed by formation of chlorophyll and an increase in extracellular cAMP. Readdition of glucose to the culture medium causes P. malhamensis to release its intracellular cAMP into the medium. These results suggest that for...

A hypothesis linking chrysophyte microfossils to lake carbon dynamics on ecological and evolutionary time scales

Scaled chrysophytes in Middle Eocene lake sediments from Northwestern Canada, including descriptions of six new species

Although chrysophyte stomatocysts have a fossil record that likely extends to the lower Cretaceous, to date neither scales nor bristles of the scaled chrysophyte genera older than Holocene have been reported. This leaves the origin of this important group of freshwater algae a mystery. We discovered abundant and diverse scaled chrysophyte microfossils in ca. 47 Ma sediments (Middle Eocene, Lute...