Format

Send to

Choose Destination
Bioresour Technol. 2018 Apr;254:278-283. doi: 10.1016/j.biortech.2018.01.036. Epub 2018 Jan 9.

Mediator-free enzymatic electrosynthesis of formate by the Methanococcus maripaludis heterodisulfide reductase supercomplex.

Author information

1
VTT Technical Research Centre of Finland Ltd, Espoo 02150, Finland; Department of Civil and Environmental Engineering, Stanford University, Stanford, CA 94305, USA.
2
Department of Civil and Environmental Engineering, Stanford University, Stanford, CA 94305, USA.
3
Tri-Institutional Training Program in Computational Biology and Medicine, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
4
Department of Civil and Environmental Engineering, Stanford University, Stanford, CA 94305, USA; Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA. Electronic address: spormann@stanford.edu.

Abstract

Electrosynthesis of formate is a promising technology to convert CO2 and electricity from renewable sources into a biocompatible, soluble, non-flammable, and easily storable compound. In the model methanogen Methanococcus maripaludis, uptake of cathodic electrons was shown to proceed indirectly via formation of formate or H2 by undefined, cell-derived enzymes. Here, we identified that the multi-enzyme heterodisulfide reductase supercomplex (Hdr-SC) of M. maripaludis is capable of direct electron uptake and catalyzes rapid H2 and formate formation in electrochemical reactors (-800 mV vs Ag/AgCl) and in Fe(0) corrosion assays. In Fe(0) corrosion assays and electrochemical reactors, purified Hdr-SC primarily catalyzed CO2 reduction to formate with a coulombic efficiency of 90% in the electrochemical cells for 5 days. Thus, this report identified the first enzyme that stably catalyzes the mediator-free electrochemical reduction of CO2 to formate, which can serve as the basis of an enzyme electrode for sustained electrochemical production of formate.

KEYWORDS:

Direct electron transfer; Electrochemical synthesis of formate; Enzyme electrode; Heterodisulfide reductase; Microbial electrosynthesis

PMID:
29413934
DOI:
10.1016/j.biortech.2018.01.036
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center