The team at the Max Planck Institute (MPI) was led by Alfred Holzwarth. His coworkers, Marc Mller and Chavdar Slavov, used lasers that sent out pulses of light lasting only 60 millionths of one billionth of a second to investigate the electron transfer processes in the two branches of PSI. This allowed them to look at extremely early events in the photosynthetic mechanism, events occurring in just a few picoseconds (a millionth of a millionth of a second), which is a time so short that a typical lattice atom could only execute a dozen oscillations on its lattice site.
This extremely sophisticated experiment and analysis required two years of laboratory effort from Rajiv Luthra, a graduate student in the Redding laboratory, to prepare a sample of sufficient purity to use. To interpret the observations, the researchers at the MPI had to develop a specific kinetic modeling approach that allowed them to estimate the individual electron transfer rates within the two branches. Comparison of mutants made in each branch with the non-mutant PSI was crucial to untangle these rates.
The current research is important for two separate reasons. Firstly, an understanding of how these complex processes work in Nature is crucial to future fundamental research in photosynthetic reaction centers, and this discovery may well be universal. Secondly, the use of two charge separation devices working cooperatively to maximize efficiency is a design theme that may well be applied in future efforts to create artificial photosynthetic devices.
Our society has urgent need of a renewable source of fuel that is widely distributed geographically, abundant, inexpensive, and environmentally clean. The use of solar energy to produce a clean fuel such as hydroge
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Arizona State University