Vitamin K1 (phylloquinone) restores the turnover of FeS centers in the ether‐extracted spinach PS I particles

FEBS Letters

Itoh, Shigeru¹  Iwaki, Masayo¹ 

[1] National Institute for Basic Biology, 38 Nishigonaka, Myodaijicho, Okazaki 444, Japan

关键词: Iron sulfur center;    Quinone;    Phylloquinone;    Vitamin K1;    Photosystem I;    Charge recombination;    PS I photosystem I;    VK1;    vitamin K1 (phylloquinone);    A0 and A1;    photosystem I electron acceptor intermediate chlorophyll a and the primary electron acceptor;    respectively;    E m;    redox midpoint potential;   

DOI  :  10.1016/0014-5793(89)81215-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The effects of vitamin K₁ (phylloquinone) addition on the turnover of the FeS centers in photosysten, I photochemistry were studied in diethyl ether-extracted spinach photosystem I particles. Reconstitution of one Molecule of vitamin K₁/reaction center was sufficient to suppress the charge recombination between the oxidized reaction center chlorophyll P700⁺ and the reduced electron acceptor intermediate chlorophyll a and to restore the turnover of FeS centers in the ether-extracted particles. This strongly suggests that reconstituted vitamin K₁, functions the primary electron acceptor A₁ and exhibits a redox midpoint potential low enough to reduce the FeS centers. The quinone binding site in photosystem I, which enables vitamin K₁ to show such a low redox potential, seems to be more hydrophobic than those in reaction centers of photosystem II or purple bacteria.

【 授权许可】

Unknown