The team includes HZB physicist Dr. Philippe Wernet, chemist Prof. Dr. Athina Zouni of Humboldt University of Berlin, Dr. Uwe Bergmann of the SLAC National Accelerator Laboratory and Dr. Junko Yano of the Lawrence Berkeley National Laboratory, who is in charge of the project.
In spite of the fact that all aerobic organisms consume oxygen, thankfully, we don't ever run out of it. Because as part of photosynthesis, green plants, algae, and cyanobacteria all assemble carbohydrates from CO2, water, and sunlight, and in the process once again give off oxygen. Here, splitting of oxygen from water, the central reaction in photosystem II, a membrane bound multi-subunit protein, only becomes possible through the presence of a catalyst, a complex molecule with an Mn4CaO5 core. A team of HZB researchers, their Berlin and US colleagues is exploring the reactions involving this natural catalyst. New insights would not just be fundamentally exciting but could potentially also contribute to the storage of solar energy in the form of solar fuels to help solve one of the major challenges in the transitioning energy economy.
At the same time, the team has recently come up with a new approach that goes far beyond conventional X-ray crystallography and spectroscopy at low temperatures. Because as long as the investigations are done at temperatures near absolute zero, they don't even come close to resembling real-life conditions. What is more, the X-rays also damage the catalyst molecules. The intense and ultrashort femtosecond X-ray pulses at the Linac Coherent Light Source, the SLAC National Accelerator Laboratory's free electron laser in Stanford, USA, are capable of collecting data at room temperature and, in the process, detecting signals before the sample is destroyed. "What we're doing here is taking sort of a snap shot of the reaction," explains Philippe Wernet.
The researchers want to study protein structure and reaction dynamics of the Mn4CaO5
|Contact: Dr. Antonia Rötger|
Helmholtz Association of German Research Centres