Concerted One-Electron Two-Proton Transfer Processes in Models Inspired by the Tyr-His Couple of Photosystem II

Mioy T. Huynh, S. Jimena Mora, Matias Villalba, Marely E. Tejeda-Ferrari, Paul A. Liddell, Brian R. Cherry, Anne Lucie Teillout, Charles W. MacHan, Clifford P. Kubiak, Devens Gust, Thomas A. Moore, Sharon Hammes-Schiffer, Ana L. Moore

Research output: Contribution to journalArticle

38 Citations (Scopus)

Abstract

Nature employs a TyrZ-His pair as a redox relay that couples proton transfer to the redox process between P680 and the water oxidizing catalyst in photosystem II. Artificial redox relays composed of different benzimidazole-phenol dyads (benzimidazole models His and phenol models Tyr) with substituents designed to simulate the hydrogen bond network surrounding the TyrZ-His pair have been prepared. When the benzimidazole substituents are strong proton acceptors such as primary or tertiary amines, theory predicts that a concerted two proton transfer process associated with the electrochemical oxidation of the phenol will take place. Also, theory predicts a decrease in the redox potential of the phenol by -300 mV and a small kinetic isotope effect (KIE). Indeed, electrochemical, spectroelectrochemical, and KIE experimental data are consistent with these predictions. Notably, these results were obtained by using theory to guide the rational design of artificial systems and have implications for managing proton activity to optimize efficiency at energy conversion sites involving water oxidation and reduction.

Original languageEnglish
Pages (from-to)372-380
Number of pages9
JournalACS Central Science
Volume3
Issue number5
DOIs
Publication statusPublished - May 24 2017

ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)

Fingerprint Dive into the research topics of 'Concerted One-Electron Two-Proton Transfer Processes in Models Inspired by the Tyr-His Couple of Photosystem II'. Together they form a unique fingerprint.

  • Cite this

    Huynh, M. T., Mora, S. J., Villalba, M., Tejeda-Ferrari, M. E., Liddell, P. A., Cherry, B. R., Teillout, A. L., MacHan, C. W., Kubiak, C. P., Gust, D., Moore, T. A., Hammes-Schiffer, S., & Moore, A. L. (2017). Concerted One-Electron Two-Proton Transfer Processes in Models Inspired by the Tyr-His Couple of Photosystem II. ACS Central Science, 3(5), 372-380. https://doi.org/10.1021/acscentsci.7b00125