Photosynthesis sustains most of the life on our planet. It harvests energy from sunlight, while generating oxygen and removing carbon dioxide from the atmosphere. The process takes place in the chloroplasts of plants and algae. Researchers in the team of Wolfgang Baumeister at the Max Planck Institute of Biochemistry in Martinsried near Munich were recently successful in revealing the native structure of the chloroplast in 3D.
“The results are the first of their kind and provide us with new insights into the mechanisms of photosynthesis”, says Benjamin Engel, first author of the study. The results were recently published in the journal eLife.
So far, researchers who wanted to observe tiny structures inside of cells had to use traditional electron microscopy. However, this method requires several preparation steps that damage cellular structures and limit the resolution and accuracy of the images. By using cryo-electron tomography, Wolfgang Baumeister and his team are able to avoid these steps by rapidly freezing the cells. Moreover, this allows them to visualize the internal architecture of cells in a close-to-living state. Using this technique, the scientists investigated the three dimensional structures of chloroplasts in the alga Chlamydomonas, shedding new light on their assembly and function.
Two spatially separated reactions take place during photosynthesis: while energy is harvested from sunlight in compartments called the thylakoids, carbon dioxide is fixed to form sugar molecules in a compartment called the pyrenoid. It was not understood how these processes could be coordinated. The new 3D images revealed the detailed structures of tubules that connect the pyrenoid with the thylakoids, providing conduits for the diffusion of energy molecules and sugars between these two separated parts of the chloroplast (see figure).
Besides the fact that there are connections between the two reaction compartments, the scientists were also able to show how the thylakoids receive new proteins and how the photosynthesis enzymes are organized: “In the pyrenoid, there are many units of the photosynthesis enzyme RuBisCO”, explains Benjamin Engel, scientist at the MPI of Biochemistry. “Our results show for the first time that these units are packed in a hexagonal arrangement.” In the future, the authors aim to elucidate how this RuBisCO organization is formed and whether more proteins are involved. [HS]
Engel B, Schaffer M, Kuhn Cuellar L, Villa E, Plitzko JM and Baumeister W: Native Architecture of the Chlamydomonas Chloroplast Revealed by In Situ Cryo-Electron Tomography. eLife, January 13, 2015.
Prof. Dr. Wolfgang Baumeister
Molecular Structural Biology
Max Planck Institute of Biochemistry
Am Klopferspitz 18
Max Planck Institute of Biochemistry
Am Klopferspitz 18
Phone: +49 89 8578-2824
http://www.biochem.mpg.de/baumeister - Website of the Research Department "Molecular Structural Biology" (Prof. Dr. Wolfgang Baumeister)
http://www.biochem.mpg.de/news - More press releases of the MPI of Biochemistry
Anja Konschak | Max-Planck-Institut für Biochemie
Transport of molecular motors into cilia
28.03.2017 | Aarhus University
Asian dust providing key nutrients for California's giant sequoias
28.03.2017 | University of California - Riverside
The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.
To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
28.03.2017 | Life Sciences
28.03.2017 | Information Technology
28.03.2017 | Physics and Astronomy