Structural insights into the light-driven auto-assembly process of the water-oxidizing Mn4CaO5-cluster in photosystem II.Zhang, M., Bommer, M., Chatterjee, R., Hussein, R., Yano, J., Dau, H., Kern, J., Dobbek, H., Zouni, A.
(2017) Elife 6: --
- PubMed: 28718766
- DOI: 10.7554/eLife.26933
- PubMed Abstract:
In plants, algae and cyanobacteria, Photosystem II (PSII) catalyzes the light-driven splitting of water at a protein-bound Mn <sub>4 </sub>CaO <sub>5 </sub>-cluster, the water-oxidizing complex (WOC). In the photosynthetic organisms, the light-driven ...
In plants, algae and cyanobacteria, Photosystem II (PSII) catalyzes the light-driven splitting of water at a protein-bound Mn 4 CaO 5 -cluster, the water-oxidizing complex (WOC). In the photosynthetic organisms, the light-driven formation of the WOC from dissolved metal ions is a key process because it is essential in both initial activation and continuous repair of PSII. Structural information is required for understanding of this chaperone-free metal-cluster assembly. For the first time, we obtained a structure of PSII from Thermosynechococcus elongatus without the Mn 4 CaO 5 -cluster. Surprisingly, cluster-removal leaves the positions of all coordinating amino acid residues and most nearby water molecules largely unaffected, resulting in a pre-organized ligand shell for kinetically competent and error-free photo-assembly of the Mn 4 CaO 5 -cluster. First experiments initiating (i) partial disassembly and (ii) partial re-assembly after complete depletion of the Mn 4 CaO 5 -cluster agree with a specific bi-manganese cluster, likely a di-µ-oxo bridged pair of Mn(III) ions, as an assembly intermediate.
Institut für Biologie, Humboldt-Universität zu Berlin, Berlin, Germany.,Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, United States.,Freie Universität Berlin, Berlin, Germany.