Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8654, Japan.
Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8904, Japan.
Photosynth Res. 2021 Jun;148(3):153-159. doi: 10.1007/s11120-021-00846-y. Epub 2021 May 28.
Photosystem II (PSII) contains Ca, which is essential to the oxygen-evolving activity of the catalytic MnCaO complex. Replacement of Ca with other redox-inactive metals results in a loss/decrease of oxygen-evolving activity. To investigate the role of Ca in this catalytic reaction, we investigate artificial Mn[M]O clusters redox-inactive metals [M] ([M] = Mg, Ca, Zn, Sr, and Y), which were synthesized by Tsui et al. (Nat Chem 5:293, 2013). The experimentally measured redox potentials (E) of these clusters are best described by the energy of their highest occupied molecular orbitals. Quantum chemical calculations showed that the valence of metals predominantly affects E(Mn), whereas the ionic radius of metals affects E(Mn) only slightly.
光系统 II（PSII）含有 Ca，这对于催化 MnCaO 配合物的释氧活性是必不可少的。用其他氧化还原惰性金属替代 Ca 会导致释氧活性丧失/降低。为了研究 Ca 在这个催化反应中的作用，我们研究了 Tsui 等人合成的人工 Mn[M]O 簇氧化还原惰性金属 [M]（[M] = Mg、Ca、Zn、Sr 和 Y）（Nat Chem 5:293, 2013）。这些簇的实验测量的氧化还原电位（E）最好由它们的最高占据分子轨道的能量来描述。量子化学计算表明，金属的化合价主要影响 E（Mn），而金属的离子半径仅对 E（Mn）有轻微影响。
