A bioinspired redox relay that mimics radical interactions of the Tyr-His pairs of photosystem II.

Jackson D. Megiatto, Dalvin D. Méndez-Hernández, Marely E. Tejeda-Ferrari, Anne Lucie Teillout, Manuel J. Llansola-Portolés, Gerdenis Kodis, Oleg G. Poluektov, Tijana Rajh, Vladimiro Mujica, Thomas L. Groy, Devens Gust, Thomas A. Moore, Ana L. Moore

Research output: Contribution to journalArticle


In water-oxidizing photosynthetic organisms, light absorption generates a powerfully oxidizing chlorophyll complex (P680(•+)) 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(•+), 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.

Original languageEnglish
Pages (from-to)423-428
Number of pages6
JournalNature Chemistry
Issue number5
Publication statusPublished - 2014


ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)

Cite this

Megiatto, J. D., Méndez-Hernández, D. D., Tejeda-Ferrari, M. E., Teillout, A. L., Llansola-Portolés, M. J., Kodis, G., Poluektov, O. G., Rajh, T., Mujica, V., Groy, T. L., Gust, D., Moore, T. A., & Moore, A. L. (2014). A bioinspired redox relay that mimics radical interactions of the Tyr-His pairs of photosystem II. Nature Chemistry, 6(5), 423-428. https://doi.org/10.1038/nchem.1862