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A synthetic Mn4Ca-cluster mimicking the oxygen-evolving center of photosynthesis

投稿者: Yuma Morimoto

  • Jingquan Zhao1

    • +Author Affiliations
    1. 1Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
    2. 2College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001, China.
    3. 3Photosynthesis Research Center, Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan.
    4. 4Department of Physics, Free University Berlin, Arnimallee 14, 14195 Berlin, Germany.
    1. ↵*Corresponding author. E-mail: chunxizhang@iccas.ac.cn (C.Z.); dhongxing@hrbeu.edu.cn (H.D.); holger.dau@fu-berlin.de (H.D.)
    Photosynthetic splitting of water into oxygen by plants, algae, and cyanobacteria is catalyzed by the oxygen-evolving center (OEC). Synthetic mimics of the OEC, which is composed of an asymmetric manganese-calcium-oxygen cluster bound to protein groups, may promote insight into the structural and chemical determinants of biological water oxidation and lead to development of superior catalysts for artificial photosynthesis. We synthesized a Mn4Ca-cluster similar to the native OEC in both the metal-oxygen core and the binding protein groups. Like the native OEC, the synthetic cluster can undergo four redox transitions and shows two magnetic resonance signals assignable to redox and structural isomerism. Comparison with previously synthesized Mn3CaO4-cubane clusters suggests that the fourth Mn ion determines redox potentials and magnetic properties of the native OEC.
    • Received for publication 9 January 2015.
    • Accepted for publication 2 April 2015.


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    OECモデルとなる錯体の報告です。キュバン型クラスタの頂点の一つがMnからCaに置き換わった報告が2013年のAgapieらのサイエンスでしたが、さらにクラスタ外のMnまで再現したフループが現れました。Agapieらは良くデザインされた三回対称性の配位子を使い、精密にクラスタを合成しましたが、このグループの合成法は、ピバル酸とMn、Caをグツグツにるだけで作っている所も驚きです。いちおう４電子分のレドックス能ももつようです。


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