LaCl3提高菠菜光系统Ⅱ活性的作用机制

The effect of LaCl3 on the K3Fe(CN)6 (FeCy) reduction rate and the oxygen-evolving rate of PSU particles of spinach, and the spectral characterization of the D1/D2/Cytb559 of a PSII reaction center complex consisting of three polypeptides from spinach were studied. The experimental results showed that LaCl3 could significantly accelerate the transformation from light energy to electric energy, the electron transport, water photolysis and oxygen evolution of PSII of spinach, which was related to the spectral characterization of the D1/D2/Cytb559 complex.Soret band and Q band of Chl-a of UV-vis spectrum of D1/D2/Cytb559 complex were blue shifted, and the fluorescence emission peak was blue shifted in LaCl3 treated spinach compared with that in the control. The EXAFS (extended X-ray absorption fine structure spectroscopy) revealed that La^3 was coordinated with 8 nitrogen or oxygen atoms in the first coordination shell with La-N or La-O bond length of 0.254 nm, and with 6 nitrogen or oxygen atoms in the second coordination shell with La-N or La-O bond length of 0.321 nm in the D1/D2/Cytb559 complex. The CD suggested that the secondary structure of D1/D2/Cytb559 complex have been litfie affected by the treatment of LaCl3.

Mechanism of LaCl3 on Increasing Photosystem II Activity of Spinach

The effect of LaCl₃ on the K₃Fe(CN)₆ (FeCy) reduction rate and the oxygen‐evolving rate of PSII particles of spinach, and the spectral characterization of the D1/D2/Cytb559 of a PSII reaction center complex consisting of three polypeptides from spinach were studied. The experimental results showed that LaCl₃ could significantly accelerate the transformation from light energy to electric energy, the electron transport, water photolysis and oxygen evolution of PSII of spinach, which was related to the spectral characterization of the D1/D2/Cytb559 complex. Soret band and Q band of Chl‐a of UV‐vis spectrum of D1/D2/Cytb559 complex were blue shifted, and the fluorescence emission peak was blue shifted in LaCl₃ treated spinach compared with that in the control. The EXAFS (extended X‐ray absorption fine structure spectroscopy) revealed that La³⁺ was coordinated with 8 nitrogen or oxygen atoms in the first coordination shell with La? N or La? O bond length of 0.254 nm, and with 6 nitrogen or oxygen atoms in the second coordination shell with La? N or La? O bond length of 0.321 nm in the D1/D2/Cytb559 complex. The CD suggested that the secondary structure of D1/D2/Cytb559 complex have been little affected by the treatment of LaCl₃.