Retuning the Catalytic Bias and Overpotential of a [NiFe]-Hydrogenase via a Single Amino Acid Exchange at the Electron Entry/Exit Site

Hope Adamson, Martin Robinson, John J. Wright, Lindsey Anne Flanagan, Julia Walton, Darrell M Elton, David J Gavaghan, Alan M Bond, Maxie M. Roessler, Alison Parkin

Research output: Contribution to journalArticlepeer-review


The redox chemistry of the electron entry/exit site in Escherichia coli hydrogenase-1 is shown to play a vital role in tuning biocatalysis. Inspired by nature, we generate a HyaA-R193L variant to disrupt a proposed Arg-His cation-π interaction in the secondary coordination sphere of the outermost, "distal", iron-sulfur cluster. This rewires the enzyme, enhancing the relative rate of H 2 production and the thermodynamic efficiency of H 2 oxidation catalysis. On the basis of Fourier transformed alternating current voltammetry measurements, we relate these changes in catalysis to a shift in the distal [Fe 4S 4] 2+/1+ redox potential, a previously experimentally inaccessible parameter. Thus, metalloenzyme chemistry is shown to be tuned by the second coordination sphere of an electron transfer site distant from the catalytic center.

Original languageEnglish
Pages (from-to)10677-10686
Number of pages10
JournalJournal of the American Chemical Society
Issue number31
Early online date26 Jul 2017
Publication statusPublished - 9 Aug 2017

Bibliographical note

© 2017 American Chemical Society.


  • Amino Acids/chemistry
  • Catalysis
  • Electrons
  • Hydrogen/chemistry
  • Hydrogenase/chemistry
  • Oxidation-Reduction

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