7NHO

Structure of PSII-M

Summary for 7NHO

• Entry DOI: 10.2210/pdb7nho/pdb
• EMDB information: 12335
• Descriptor: Photosystem II protein D1 1, Photosystem II reaction center protein L, Photosystem II reaction center protein M, ... (26 entities in total)
• Functional Keywords: membrane protein biogenesis assembly factors photosystem ii, photosynthesis
• Biological source: Thermosynechococcus elongatus BP-1; More
• Total number of polymer chains: 15
• Total formula weight: 292739.48

Authors

Zabret, J.,Bohn, S.,Schuller, S.K.,Arnolds, O.,Chan, A.,Tajkhorshid, E.,Stoll, R.,Engel, B.D.,Rudack, T.,Schuller, J.M.,Nowaczyk, M.M. (deposition date: 2021-02-11, release date: 2021-05-05, Last modification date: 2024-05-01)

Primary citation

Zabret, J.,Bohn, S.,Schuller, S.K.,Arnolds, O.,Moller, M.,Meier-Credo, J.,Liauw, P.,Chan, A.,Tajkhorshid, E.,Langer, J.D.,Stoll, R.,Krieger-Liszkay, A.,Engel, B.D.,Rudack, T.,Schuller, J.M.,Nowaczyk, M.M.
Structural insights into photosystem II assembly.
Nat.Plants, 7:524-538, 2021

PubMed Abstract: Biogenesis of photosystem II (PSII), nature's water-splitting catalyst, is assisted by auxiliary proteins that form transient complexes with PSII components to facilitate stepwise assembly events. Using cryo-electron microscopy, we solved the structure of such a PSII assembly intermediate from Thermosynechococcus elongatus at 2.94 Å resolution. It contains three assembly factors (Psb27, Psb28 and Psb34) and provides detailed insights into their molecular function. Binding of Psb28 induces large conformational changes at the PSII acceptor side, which distort the binding pocket of the mobile quinone (Q) and replace the bicarbonate ligand of non-haem iron with glutamate, a structural motif found in reaction centres of non-oxygenic photosynthetic bacteria. These results reveal mechanisms that protect PSII from damage during biogenesis until water splitting is activated. Our structure further demonstrates how the PSII active site is prepared for the incorporation of the MnCaO cluster, which performs the unique water-splitting reaction.

PubMed: 33846594
DOI: 10.1038/s41477-021-00895-0

Experimental method

ELECTRON MICROSCOPY (2.66 Å)