TY - JOUR
T1 - A bioinspired redox relay that mimics radical interactions of the Tyr-His pairs of photosystem II
AU - Megiatto, Jackson D.
AU - Méndez-Hernández, Dalvin D.
AU - Tejeda-Ferrari, Marely E.
AU - Teillout, Anne Lucie
AU - Llansola-Portolés, Manuel J.
AU - Kodis, Gerdenis
AU - Poluektov, Oleg G.
AU - Rajh, Tijana
AU - Mujica, Vladimiro
AU - Groy, Thomas L.
AU - Gust, Devens
AU - Moore, Thomas
AU - Moore, Ana
PY - 2014/5
Y1 - 2014/5
N2 - In water-oxidizing photosynthetic organisms, light absorption generates a powerfully oxidizing chlorophyll complex (P680 â €¢ +) in the photosystem II reaction centre. This is reduced via an electron transfer pathway from the manganese-containing water-oxidizing catalyst, which includes an electron transfer relay comprising a tyrosine (Tyr)-histidine (His) pair that features a hydrogen bond between a phenol group and an imidazole group. By rapidly reducing P680 â €¢ +, the relay is thought to mitigate recombination reactions, thereby ensuring a high quantum yield of water oxidation. Here, we show that an artificial reaction centre that features a benzimidazole-phenol model of the Tyr-His pair mimics both the short-internal hydrogen bond in photosystem II and, using electron paramagnetic resonance spectroscopy, the thermal relaxation that accompanies proton-coupled electron transfer. Although this artificial system is much less complex than the natural one, theory suggests that it captures the essential features that are important in the function of the relay.
AB - In water-oxidizing photosynthetic organisms, light absorption generates a powerfully oxidizing chlorophyll complex (P680 â €¢ +) in the photosystem II reaction centre. This is reduced via an electron transfer pathway from the manganese-containing water-oxidizing catalyst, which includes an electron transfer relay comprising a tyrosine (Tyr)-histidine (His) pair that features a hydrogen bond between a phenol group and an imidazole group. By rapidly reducing P680 â €¢ +, the relay is thought to mitigate recombination reactions, thereby ensuring a high quantum yield of water oxidation. Here, we show that an artificial reaction centre that features a benzimidazole-phenol model of the Tyr-His pair mimics both the short-internal hydrogen bond in photosystem II and, using electron paramagnetic resonance spectroscopy, the thermal relaxation that accompanies proton-coupled electron transfer. Although this artificial system is much less complex than the natural one, theory suggests that it captures the essential features that are important in the function of the relay.
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U2 - 10.1038/nchem1862
DO - 10.1038/nchem1862
M3 - Article
C2 - 24755594
AN - SCOPUS:84899082031
SN - 1755-4330
VL - 6
SP - 423
EP - 428
JO - Nature Chemistry
JF - Nature Chemistry
IS - 5
ER -