8F4E

RT XFEL structure of Photosystem II 250 microseconds after the third illumination at 2.09 Angstrom resolution

Summary for 8F4E

• Entry DOI: 10.2210/pdb8f4e/pdb
• Descriptor: Photosystem II protein D1 1, Photosystem II reaction center protein K, Photosystem II reaction center protein L, ... (37 entities in total)
• Functional Keywords: water oxidation, oec, manganese cluster, photosynthesis
• Biological source: Thermosynechococcus vestitus BP-1; More
• Total number of polymer chains: 40
• Total formula weight: 758862.36

Authors

Bhowmick, A.,Hussein, R.,Bogacz, I.,Simon, P.S.,Ibrahim, M.,Chatterjee, R.,Doyle, M.D.,Cheah, M.H.,Fransson, T.,Chernev, P.,Kim, I.-S.,Makita, H.,Dasgupta, M.,Kaminsky, C.J.,Zhang, M.,Gatcke, J.,Haupt, S.,Nangca, I.I.,Keable, S.M.,Aydin, O.,Tono, K.,Owada, S.,Gee, L.B.,Fuller, F.D.,Batyuk, A.,Alonso-Mori, R.,Holton, J.M.,Paley, D.W.,Moriarty, N.W.,Mamedov, F.,Adams, P.D.,Brewster, A.S.,Dobbek, H.,Sauter, N.K.,Bergmann, U.,Zouni, A.,Messinger, J.,Kern, J.,Yano, J.,Yachandra, V.K. (deposition date: 2022-11-10, release date: 2023-03-22, Last modification date: 2024-10-16)

Primary citation

Bhowmick, A.,Hussein, R.,Bogacz, I.,Simon, P.S.,Ibrahim, M.,Chatterjee, R.,Doyle, M.D.,Cheah, M.H.,Fransson, T.,Chernev, P.,Kim, I.S.,Makita, H.,Dasgupta, M.,Kaminsky, C.J.,Zhang, M.,Gatcke, J.,Haupt, S.,Nangca, I.I.,Keable, S.M.,Aydin, A.O.,Tono, K.,Owada, S.,Gee, L.B.,Fuller, F.D.,Batyuk, A.,Alonso-Mori, R.,Holton, J.M.,Paley, D.W.,Moriarty, N.W.,Mamedov, F.,Adams, P.D.,Brewster, A.S.,Dobbek, H.,Sauter, N.K.,Bergmann, U.,Zouni, A.,Messinger, J.,Kern, J.,Yano, J.,Yachandra, V.K.
Structural evidence for intermediates during O 2 formation in photosystem II.
Nature, 617:629-636, 2023

PubMed Abstract: In natural photosynthesis, the light-driven splitting of water into electrons, protons and molecular oxygen forms the first step of the solar-to-chemical energy conversion process. The reaction takes place in photosystem II, where the MnCaO cluster first stores four oxidizing equivalents, the S to S intermediate states in the Kok cycle, sequentially generated by photochemical charge separations in the reaction center and then catalyzes the O-O bond formation chemistry. Here, we report room temperature snapshots by serial femtosecond X-ray crystallography to provide structural insights into the final reaction step of Kok's photosynthetic water oxidation cycle, the S→[S]→S transition where O is formed and Kok's water oxidation clock is reset. Our data reveal a complex sequence of events, which occur over micro- to milliseconds, comprising changes at the MnCaO cluster, its ligands and water pathways as well as controlled proton release through the hydrogen-bonding network of the Cl1 channel. Importantly, the extra O atom O, which was introduced as a bridging ligand between Ca and Mn1 during the S→S transition, disappears or relocates in parallel with Y reduction starting at approximately 700 μs after the third flash. The onset of O evolution, as indicated by the shortening of the Mn1-Mn4 distance, occurs at around 1,200 μs, signifying the presence of a reduced intermediate, possibly a bound peroxide.

PubMed: 37138085
DOI: 10.1038/s41586-023-06038-z

Experimental method

X-RAY DIFFRACTION (2.09 Å)