Light-Induced Electron Transfer in a [NiFe] Hydrogenase Opens a Photochemical Shortcut for Catalytic Dihydrogen Cleavage.

Autor: Karafoulidi-Retsou C; Institut für Chemie, Sekr. PC14, Technische Universität Berlin, Straße des 17. Juni 135, D-10623, Berlin, Germany., Lorent C; Institut für Chemie, Sekr. PC14, Technische Universität Berlin, Straße des 17. Juni 135, D-10623, Berlin, Germany., Katz S; Institut für Chemie, Sekr. PC14, Technische Universität Berlin, Straße des 17. Juni 135, D-10623, Berlin, Germany., Rippers Y; Fachbereich Physik, Freie Universität Berlin, Arnimallee 14, D-14195, Berlin, Germany., Matsuura H; Life Science Research Infrastructure Group, RIKEN/SPring-8 Center, 1.1.1 Kouto, Sayo-cho, Sayo-gun, Hyogo, 679-5148, Japan., Higuchi Y; Graduate School of Science, University of Hyogo, 3-2-1 Koto, Kamigori-cho, Ako-gun, Hyogo, 678-1297, Japan., Zebger I; Institut für Chemie, Sekr. PC14, Technische Universität Berlin, Straße des 17. Juni 135, D-10623, Berlin, Germany., Horch M; Fachbereich Physik, Freie Universität Berlin, Arnimallee 14, D-14195, Berlin, Germany.
Jazyk: angličtina
Zdroj: Angewandte Chemie (International ed. in English) [Angew Chem Int Ed Engl] 2024 Oct 21; Vol. 63 (43), pp. e202409065. Date of Electronic Publication: 2024 Sep 17.
DOI: 10.1002/anie.202409065
Abstrakt: [NiFe] hydrogenases catalyze the reversible cleavage of molecular hydrogen into protons and electrons. Here, we have studied the impact of temperature and illumination on an oxygen-tolerant and thermostable [NiFe] hydrogenase by IR and EPR spectroscopy. Equilibrium mixtures of two catalytic [NiFe] states, Ni a -C and Ni a -SR'', were found to drastically change with temperature, indicating a thermal exchange of electrons between the [NiFe] active site and iron-sulfur clusters of the enzyme. In addition, IR and EPR experiments performed under illumination revealed an unusual photochemical response of the enzyme. Ni a -SR'', a fully reduced hydride intermediate of the catalytic cycle, was found to be reversibly photoconverted into another catalytic state, Ni a -L. In contrast to the well-known photolysis of the more oxidized hydride intermediate Ni a -C, photoconversion of Ni a -SR'' into Ni a -L is an active-site redox reaction that involves light-driven electron transfer towards the enzyme's iron-sulfur clusters. Omitting the ground-state intermediate Ni a -C, this direct interconversion of these two states represents a potential photochemical shortcut of the catalytic cycle that integrates multiple redox sites of the enzyme. In total, our findings reveal the non-local redistribution of electrons via thermal and photochemical reaction channels and the potential of accelerating or controlling [NiFe] hydrogenases by light.
(© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)
Databáze: MEDLINE
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