Structural insights into the light-driven auto-assembly process of the water-oxidizing Mn4CaO5-cluster in photosystem II
- Humboldt-Universität zu Berlin, Germany
- Max-Delbrück-Center for Molecular Medicine, Germany
- Lawrence Berkeley National Laboratory, United States
- Freie Universität Berlin, Germany
Abstract
In plants, algae and cyanobacteria, Photosystem II (PSII) catalyzes the light-driven splitting of water at a protein-bound Mn4CaO5-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 Mn4CaO5-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 Mn4CaO5-cluster. First experiments initiating (i) partial disassembly and (ii) partial re-assembly after complete depletion of the Mn4CaO5-cluster agree with a specific bi-manganese cluster, likely a di-µ-oxo bridged pair of Mn(III) ions, as an assembly intermediate.
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Author details
Funding
Human Frontier Science Program (Project Award No. RGP0063/2013 310)
- Rana Hussein
Human Frontier Science Program (Project Award No. RGP0063/2013 310)
- Junko Yano
Human Frontier Science Program (Project Award No. RGP0063/2013 310)
- Athina Zouni
National Institutes of Health (GM055302)
- Ruchira Chatterjee
- Jan Kern
Deutsche Forschungsgemeinschaft Unifying Concepts in Catalysis (Project E3)
- Miao Zhang
- Holger Dau
- Holger Dobbek
Deutsche Forschungsgemeinschaft Sonderforschungsbereich 1078 (Project A5)
- Holger Dau
- Holger Dobbek
- Athina Zouni
Deutsche Forschungsgemeinschaft Sonderforschungbereich 1078 (Project A4)
- Martin Bommer
Biosciences of the Department of Energy (Contact number: DE-AC02-05CH11231)
- Junko Yano
- Jan Kern
Only Human Frontier Science Program (HFSP) can be found in the funder list .The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Zhang et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Structural insights into the light-driven auto-assembly process of the water-oxidizing Mn4CaO5-cluster in photosystem II
eLife 6:e26933.
https://doi.org/10.7554/eLife.26933
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