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Ultrafast structural changes within a photosynthetic reaction centre
Robert Dods1, Petra Båth1, Dmitry Morozov2
1Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden.
Nature
|December 3, 2020
Summary
Photosynthetic reaction centers use light energy by moving electrons across membranes. This study reveals how protein movements stabilize these crucial charge-separation steps.
Area of Science:
- Biochemistry
- Structural Biology
- Photosynthesis research
Background:
- Photosynthetic reaction centers are vital for converting light energy into chemical energy.
- Electron transport across biological membranes is a fundamental process in photosynthesis.
Purpose of the Study:
- To observe light-induced structural changes in the photosynthetic reaction center of Blastochloris viridis.
- To elucidate the role of protein dynamics in stabilizing charge-separation during electron transfer.
Main Methods:
- Time-resolved serial femtosecond crystallography using an X-ray free-electron laser.
- Observing structural changes on a picosecond timescale.
Main Results:
- Photo-oxidation of special pair chlorophyll molecules initiates structural perturbations.
- Electron transfer to the menaquinone acceptor causes cofactor movement and protein rearrangements.
- Conformational dynamics were observed to stabilize charge-separation.
Conclusions:
- Proteins utilize conformational dynamics to stabilize key steps in photosynthetic electron transfer.
- Structural insights were gained into the ultrafast processes within photosynthetic reaction centers.
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