Diatoms play an important role in water quality and in the global climate. They generate about one fourth of the oxygen in Earth's atmosphere and perform around one-quarter of the global CO2 assimilation, i.e. they convert carbon dioxide into organic substances. Their light receptors are a crucial factor in this process. Researchers at the Leipzig University and the Helmholtz Centre for Environmental Research have now discovered that blue and red light sensing photoreceptors control the carbon flow in these algae. These results have been recently published by the scientists in the journal PLOS ONE.
"Diatoms display a special way of reacting to light and adapting their metabolism to the changing light conditions in the water," says Prof. Dr. Christian Wilhelm, Head of the Plant Physiology Department at the Leipzig University. "For the first time, we have been able to show that the light receptors, which measure the intensity of the blue or red light, not only change the genetic transcription, but also directly control the activity of enzymes in the metabolism."
A rapid light change from blue light to red light and vice versa does not influence the photosynthesis output, but the metabolism is drastically reversed within 15 minutes. "This way, cells that have grown in red light, which continue to be cultivated in a blue light environment can still perform photosynthesis, but can no longer grow."
These "light switches" can be used to control the carbon flow in cells. The evidence for this was provided using the MetaPro metabolomic platform established at the Helmholtz Centre for Environmental Research. "This opens up new ways for the biotechnological control of cells," explains Christian Wilhelm.
The Leipzig-based algae experts in plant physiology at the Leipzig University,together with scientists from Karlsruhe and Bremen, also recently provided evidence that sunlight can be converted into pure natural gas in a highly efficient manner with the aid of microorganisms. In doing so, the metabolism of green algae is reversed.
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