Press release, October 20th, 2014

In between red light and blue light: Leipzig researchers discover new functionality of molecular light switches

Diatoms play an important role in water quality and in the global climate. They generate about one fourth of the oxygen in the 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 well-known online trade journal, PLOS ONE.

Microscopical picture of a diatom(<i>Phaeodactylum-tricornutum</i>), Source: Leipzig Univerity

Microscopical picture of a diatom (Phaeodactylum-tricornutum),
Source: Leipzig Univerity


“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.

“This work is further evidence of the added-value of intensive cooperations between non-university and university institutions, particularly with the Faculty of Biosciences, Pharmacy and Psychology”, Prof. Martin von Bergen, Spokesman of the Department of Metabolomics at the UFZ and one of the co-authors, is pleased to say.

The Leipzig-based algae experts in plant physiology at the Leipzig University already drew attention to itself two years ago with another publication: Together with scientists from Karlsruhe and Bremen, they 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.

The publication about the diatoms:

DOI: 10.1371/journal.pone.0099727
The Acclimation of Phaeodactylum tricornutum to Blue and Red Light Does Not Influence the Photosynthetic Light Reaction but Strongly Disturbs the Carbon Allocation Pattern

The publication about the green algae:

DOI: 10.1016/j.biortech.2012.06.120
Methane production from glycolate excreting algae as a new concept in the production of biofuels


Prof. Dr. Christian Wilhelm
Leipzig University, Institut for Biology, Plant Physiology
Tel.: ++49-341-97-36874

Prof. Dr. Martin von Bergen, Dr. Sven Baumann
Department of Metabolomics at the Helmholtz Centre for Environmental Research (UFZ)
Tel.: ++49-341-235-1211, -1099

or via

Susanne Hufe, Tilo Arnhold
(UFZ press office)
Tel.: ++49-341-235-1635, -1630

In the Helmholtz Centre for Environmental Research (UFZ), scientists conduct research into the causes and consequences of far-reaching environmental changes. Their areas of study cover water resources, biodiversity, the consequences of climate change and possible adaptation strategies, environmental technologies and biotech-nologies, bioenergy, the effects of chemicals in the environment and the way they influence health, modelling and social-scientific issues. Its guiding principle: Our research contributes to the sustainable use of natural resources and helps to provide long-term protection for these vital assets in the face of global change. The UFZ employs more than 1,100 staff at its sites in Leipzig, Halle and Magdeburg. It is funded by the federal government, Saxony and Saxony-Anhalt.

The Helmholtz Association contributes to solving major and urgent issues in society, science and industry through scientific excellence in six research areas: Energy, earth and environment, health, key technologies, structure of matter as well as aviation, aerospace and transportation. The Helmholtz Association is the largest scientific organisation in Germany, with 35,000 employees in 18 research centres and an annual budget of around €3.8 billion. Its work is carried out in the tradition of the great natural scientist Hermann von Helmholtz (1821-1894).