Ultrafast structural changes within a photosynthetic reaction centre

Photosynthetic reaction centres harvest the energy content of sunlight by transporting electrons across an energy-transducing biological membrane.

Here we use time-resolved serial femtosecond crystallography using an X-ray free-electron laser to observe light-induced structural changes in the photosynthetic reaction centre of Blastochloris viridis on a timescale of picoseconds.

Structural perturbations first occur at the special pair of chlorophyll molecules of the photosynthetic reaction centre that are photo-oxidized by light. Electron transfer to the menaquinone acceptor on the opposite side of the membrane induces a movement of this cofactor together with lower amplitude protein rearrangements.

These observations reveal how proteins use conformational dynamics to stabilize the charge-separation steps of electron-transfer reactions.

Preprint DOI

Citation

Robert Dods, Petra Båth, Dmitry Morozov, Viktor Ahlberg Gagnér, David Arnlund, Hoi Ling Luk, Joachim Kübel, Michał Maj, Adams Vallejos, Cecilia Wickstrand, Robert Bosman, Kenneth R. Beyerlein, Garrett Nelson, Mengning Liang, Despina Milathianaki, Joseph Robinson, Rajiv Harimoorthy, Peter Berntsen, Erik Malmerberg, Linda Johansson, Rebecka Andersson, Sergio Carbajo, Elin Claesson, Chelsie E. Conrad, Peter Dahl, Greger Hammarin, Mark S. Hunter, Chufeng Li, Stella Lisova, Antoine Royant, Cecilia Safari, Amit Sharma, Garth J. Williams, Oleksandr Yefanov, Sebastian Westenhoff, Jan Davidsson, Daniel P. DePonte, Sébastien Boutet, Anton Barty, Gergely Katona, Gerrit Groenhof, Gisela Brändén & Richard Neutze (2020):
Ultrafast structural changes within a photosynthetic reaction centre.
Nature 589
https://doi.org/10.1038/s41586-020-3000-7 [preprint]