Heterotrophy in Diatoms

On the Origin of Heterotrophy.

The theory of autotrophic origins of life posits that the first cells on Earth satisfied their carbon needs from CO2. At hydrothermal vents, spontaneous synthesis of methane via serpentinization links an energy metabolic reaction with a geochemical homologue. If the first cells were autotrophs, how did the first heterotrophs arise, and what was their substrate? We propose that cell mass roughly...

[Diatoms in the diagnosis of drowning. I. Biology of diatoms].

Epipsammic diatoms of diatoms of Kelkit Creek (Tokat/Turkey)

In this study, diatoms in epipsammic samples, which were taken from two stations selected in Kelkit Creek (Tokat/Turkey) between March and December 2018, were analyzed. During the study, a total of 25 taxa belonging to diatoms were recorded. The diatom species represented by the highest number of taxa were Cymbela (4 taxa), Nitzschia (4 taxa), and Navicula (3 taxa). Sorensen similarity index be...

Carbon Fixation in Diatoms

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Silicon Metabolism in Diatoms

1. Cells of the fresh water diatom Navicula pelliculosa may be grown in a mineral medium containing a low concentration of silicon. When transferred to a fresh silicate solution and incubated under non-growing conditions such deficient cells rapidly take up silicon from the medium. 2. The utilization of silicon is an aerobic process. 3. When deficient cells are washed with distilled water or sa...