Open AccessNADP(H) allosterically regulates the interaction between ferredoxin and ferredoxin‐NADP + reductase
Author(s) -
KimataAriga Yoko,
Chikuma Yutaro,
Saitoh Takashi,
Miyata Masayuki,
Yanagihara Yuetsu,
Yamane Kazukiyo,
Hase Toshiharu
Publication year - 2019
Publication title -
febs open bio
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.718
H-Index - 31
ISSN - 2211-5463
DOI - 10.1002/2211-5463.12752
Subject(s) - ferredoxin , ferredoxin—nadp(+) reductase , allosteric regulation , conformational change , reductase , oxidoreductase , biochemistry , chemistry , binding site , stereochemistry , enzyme , biophysics , biology
Ferredoxin‐NADP + reductase (FNR) in plants receives electrons from ferredoxin (Fd) at the end of the photosynthetic electron transfer chain and converts NADP + to NADPH. The interaction between Fd and FNR in plants was previously shown to be attenuated by NADP(H). Here, we investigated the molecular mechanism of this phenomenon using maize FNR and Fd, as the three‐dimensional structure of this complex is available. NADPH, NADP + , and 2′5′‐ADP differentially affected the interaction, as revealed through kinetic and physical binding analyses. Site‐directed mutations of FNR which change the affinity for NADPH altered the affinity for Fd in the opposite direction to that for NADPH. We propose that the binding of NADP(H) causes a conformational change of FNR which is transferred to the Fd‐binding region through different domains of FNR, resulting in allosteric changes in the affinity for Fd.