Photosynthesis is the process used by plants to convert atmospheric carbon dioxide into the energy-rich chemicals upon which all life-forms depend. The energy trapped in these compounds comes from sunlight, and photosynthetic organisms plants, algae and certain types of bacteria capture this energy in a usable form with the help of protein complexes called photosystems. Photosystems include antenna proteins that collect incident light, and green plants have two sorts of photosystems, which respond best to light of different wavelengths. A team of researchers at LMU, led by Professor Dario Leister, has now identified a protein named PAM68 that is essential for the assembly of Photosystem II in green plants. The protein is also found in photosynthetic cyanobacteria, but there it serves a different function. "It turns out that PAM68 itself does not form part of the functional photosystem II at all", says Leister. In the longer term, the new finding may make it possible to improve the yields of important crops and might even form the basis for new types of solar cells. (Plant Cell online, 5 October 2010)
Photosynthesis can be thought of as the central pillar of the biosphere, because this set of biochemical reactions provides the oxygen and energy-rich foodstuffs upon which other organisms, including humans, subsist. The energy for the process comes from sunlight, and is captured by molecules that act as solar collectors in photosynthetic organisms, such as plants, algae and cyanobacteria. "All of these organisms possess two different photosystems, each of which responds most efficiently to light of a particular wavelength", says Professor Dario Leister of the Department of Biology I at LMU Munich.
The photosystems consist of light-absorbing chlorophyll pigments and a variety of proteins. "Assembly of these multiprotein complexes takes place in several steps and requires the participation of specific accessory proteins", explains Leister.
|Contact: Professor Dario Leister|