Activation Thermodynamics and H/D Kinetic Isotope Effect of the H_ox to H_red H⁺ Transition in [FeFe] Hydrogenase [electronic resource]

• Ngôn ngữ: eng
• Ký hiệu phân loại: 541.3 Miscellaneous topics in physical chemistry
• Thông tin xuất bản: Washington, D.C. : Oak Ridge, Tenn. : United States. Dept. of Energy. Office of Science ; Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2017
• Mô tả vật lý: Size: p. 12879-12882 : , digital, PDF file.
• Bộ sưu tập: Metadata
• ID: 263164
• Chủ đề: 1. 09 biomass fuels; 2. H2 catalysis; 3. Hydrogenase; 4. Thermodynamics

Tóm tắt

 Molecular complexes between CdSe nanocrystals and Clostridium acetobutylicum [FeFe] hydrogenase I (CaI) enabled light-driven control of electron transfer for spectroscopic detection of redox intermediates during catalytic proton reduction. Here in this paper we address the route of electron transfer from CdSe?CaI and activation thermodynamics of the initial step of proton reduction in CaI. The electron paramagnetic spectroscopy of illuminated CdSe:CaI showed how the CaI accessory FeS cluster chain (F-clusters) functions in electron transfer with CdSe. The H<
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  reduction step measured by Fourier-transform infrared spectroscopy showed an enthalpy of activation of 19 kJ mol<
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  and a ~2.5-fold kinetic isotope effect. Overall these results support electron injection from CdSe into CaI involving F-clusters, and that the H<
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  step of catalytic proton reduction in CaI proceeds by a proton-dependent process.