학술논문
Cyclic electron transfer around Photosystem I mediated by 2,3‐dichloro‐1,4‐naphtoquinone and ascorbate.
Document Type
Article
Author
Source
Subject
*CHARGE exchange
*PHOTOSYSTEMS
*QUINONE derivatives
*ASCORBATE oxidase
*ELECTROPHILES
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Language
ISSN
0014-5793
Abstract
In this work, we investigated electron transport around the photosynthetic pigment–protein complex of Photosystem I (PS I) mediated by external high‐potential electron carrier 2,3‐dichloro‐1,4‐naphtoquinone (Cl2NQ) and ascorbate. It has been demonstrated that the oxidized species of Cl2NQ and ascorbate serve as intermediates capable of accepting electrons from the iron–sulfur cluster FX of PS I. Reduced species of Cl2NQ and ascorbate are oxidized by photooxidized PS I primary donor P 700 + and/or by molecular oxygen. We have found the synergistic effect of Cl2NQ and ascorbate on the rate of P 700 + reduction. Accelerated electron flow to P 700 +, observed in the presence of both Cl2NQ and ascorbate, is explained by an increase in the reduced species of Cl2NQ due to electron transfer from ascorbate. [ABSTRACT FROM AUTHOR]