A redox-dependent interaction between two electron-transfer partners involved in photosynthesis
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Updated: Oct 9, 2026

Evaluation of Photosynthetic Efficiency in Photorespiratory Mutants by Chlorophyll Fluorescence Analysis
Published on: December 9, 2022
R Morales1, M H Charon, G Kachalova
1LCCP, Institut de Biologie Structurale J.P. Ebel, CEA-CNRS, Grenoble, France.
Abstract:
Ferredoxin:NADP+:reductase (FNR) catalyzes one terminal step of the conversion of light energy into chemical energy during photosynthesis. FNR uses two high energy electrons photoproduced by photosystem I (PSI) and conveyed, one by one, by a ferredoxin (Fd), to reduce NADP+ to NADPH. The reducing power of NADPH is finally involved in carbon assimilation. The interaction between oxidized FNR and Fd was studied by crystallography at 2.4 A resolution leading to a three-dimensional picture of an Fd-FNR biologically relevant complex. This complex suggests that FNR and Fd specifically interact prior to each electron transfer and disassemble upon a redox-linked conformational change of the Fd.
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