Infrared Spectroscopy During Electrocatalytic Turnover Reveals the Ni-L Active Site State During H2 Oxidation by a NiFe Hydrogenase.pdf (1.13 MB)
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Infrared Spectroscopy During Electrocatalytic Turnover Reveals the Ni-L Active Site State During H2 Oxidation by a NiFe Hydrogenase.

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journal contribution
posted on 03.06.2019, 13:40 by Ricardo Hidalgo, Philip A. Ash, Adam J. Healy, Kylie A. Vincent
A novel in situ IR spectroscopic approach is demonstrated for the characterization of hydrogenase during catalytic turnover. E. coli hydrogenase 1 (Hyd-1) is adsorbed on a high surface-area carbon electrode and subjected to the same electrochemical control and efficient supply of substrate as in protein film electrochemistry during spectral acquisition. The spectra reveal that the active site state known as Ni-L, observed in other NiFe hydrogenases only under illumination or at cryogenic temperatures, can be generated reversibly in the dark at ambient temperature under both turnover and non-turnover conditions. The observation that Ni-L is present at all potentials during turnover under H2 suggests that the final steps in the catalytic cycle of H2 oxidation by Hyd-1 involve sequential proton and electron transfer via Ni-L. A broadly applicable IR spectroscopic technique is presented for addressing electrode-adsorbed redox enzymes under fast catalytic turnover.

Funding

This work was supported by: European Research Council (EnergyBioCatalysis‐ERC‐2010‐StG‐258600); Biotechnology and Biological Sciences Research Council (BB/L009722/1); Engineering and Physical Sciences Research Council (EP/K031503/1). R.H. is supported by Ministerio de Ciencia y Tecnología, Universidad de Costa Rica, and Lincoln College, Oxford. We thank E. Nomerotskaia for preparing E. coli Hyd‐1.

History

Citation

Angewandte Chemie International Edition English, 2015, 54 (24), pp. 7110-7113

Author affiliation

/Organisation/COLLEGE OF SCIENCE AND ENGINEERING/Department of Chemistry

Version

VoR (Version of Record)

Published in

Angewandte Chemie International Edition English

Publisher

Wiley for Gesellschaft Deutscher Chemiker (GDCh)

eissn

1521-3773

Copyright date

2015

Available date

03/06/2019

Publisher version

https://onlinelibrary.wiley.com/doi/full/10.1002/anie.201502338

Notes

Supporting information for this article is available on the WWW under http://dx.doi.org/10.1002/anie.201502338.

Language

en