A team of scientists from Münster and the USA have now been able to show for the first time how green algae protect themselves against such damage. The journal "Nature" carries a report on this in the issue published on 26 November 2009.
Plants are dependent on sunlight for growth. With the aid of light energy they produce sugar molecules which are converted into components of their cells and act as suppliers of energy. In this process plants extract carbon dioxide from the atmosphere and release oxygen. This process - called photosynthesis - is the basis of all life on earth.
"Photosynthesis provides the vegetable biomass - and thus the basis of food supply - for people and animals," says Prof. Michael Hippler from the Institute of Biochemistry and Plant Biotechnology at Münster University.
However, using light energy to produce biomass is a tricky business for plants. The absorption of light through cellular pigment molecules, e.g. through chlorophyll, can lead to the production of oxygen radicals in plants and thus damage them. "In order to protect themselves from such oxidative destruction - 'sunburn', so to speak," says Prof. Hippler, "plants have developed mechanisms for converting the surplus light energy into heat energy. Although algae produce a large share of the biomass generated worldwide, very little was known up to now about this protective mechanism in algae - in contrast to flowering plants." An international team of scientists led by Prof. Hippler and Prof. Kris Niyogi from the University of California in Berkeley, USA, have now thrown light on this sun protection mechanism in the unicellular green alga Chlamydomonas reinhardtii.
The sun protection factor is a certain light-harvesting protein (LHCSR3). "In general," explains Prof. Hippler, "such proteins harvest light - as their name suggests - and they make it available for photosynthesis. In this particular case, however, the protein permits the conversion of light energy to heat energy and in the process it renders the surplus light energy harmless." In comparison to traditional light-harvesting proteins, LHCSR3 has very old origins, probably stemming directly from the 'forebear' of all light-harvesting proteins. If there is any obstacle to the production of this protein, the algae are no longer able to dissipate harmful excess energy. They then get 'sunburn', which can in fact result in the alga cells dying.
"Interestingly, flowering plants have lost these protein molecules during their evolution and have developed another sun protection mechanism in which light is also converted into heat energy," says Prof. Hippler. "The discovery of the 'sun protection factor' in algae makes it possible for us to have deep insights into the regulation of aquatic photosynthesis, which is responsible for 50 percent of the primary production of biomass worldwide." Moreover, he says, the insights could be used to optimize the culture of micro-algae in bio-reactors. In this way the biotechnological production of biomass from algae could be improved, e.g. for the production of bio-fuels.
Dr. Christina Heimken | idw
More genes are active in high-performance maize
19.01.2018 | Rheinische Friedrich-Wilhelms-Universität Bonn
How plants see light
19.01.2018 | Albert-Ludwigs-Universität Freiburg im Breisgau
On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.
We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...
What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...
For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.
Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...
At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.
No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...
Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.
Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...
08.01.2018 | Event News
11.12.2017 | Event News
08.12.2017 | Event News
19.01.2018 | Materials Sciences
19.01.2018 | Health and Medicine
19.01.2018 | Physics and Astronomy