The hydrophobicity of mutations targeting D1:Val219 modifies formate and diuron binding in the quinone‐Fe‐acceptor complex of Photosystem II

Abstract

The D1:Val219 residue of Photosystem II in the cyanobacterium Synechocystis sp. PCC 6803 was mutated to alanine or isoleucine, creating the V219A and V219I mutants, respectively. Oxygen evolution was slowed in these mutants, while chlorophyll a fluorescence induction assays indicated slowed electron transfer. As previously observed

Structural insights into the action mechanisms of artificial electron acceptors in photosystem II

“…Like AEAs, herbicides such as 3-(3, 4-dichlorophenyl)-1, 1-dimethylurea bind to the Q B site and inhibit photosynthesis ( 17 , 18 , 19 , 20 , 21 , 22 , 23 ). A previous study showed that herbicides bind to another site in addition to the Q B site ( 48 ).…”

“…The PQH 2 released into the membrane passes electrons to the cytochrome b 6 f complex ( 15 , 16 ), which are eventually used for the reduction of carbon dioxide into sugars. The majority of herbicides inhibiting photosynthetic electron transport bind to the Q B site ( 17 , 18 , 19 , 20 , 21 , 22 , 23 ).

Figure 1 Structures of the acceptor side of PSII and artificial electron acceptors used in this study.

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