TY - JOUR
T1 - Mediator-free enzymatic electrosynthesis of formate by the Methanococcus maripaludis heterodisulfide reductase supercomplex
AU - Lienemann, Michael
AU - Deutzmann, Jörg Stefan
AU - Milton, Ross Dean
AU - Sahin, Merve
AU - Spormann, Alfred Michael
N1 - Funding Information:
We thank the Stanford University Mass Spectrometry Facility for proteomic analysis (peptide mass fingerprinting). Support of this research by grants by Office of Naval Research (USA; Contract. No. N000141612240) and GCEP to AMS, and Emil Aaltonen Foundation (Finland) travel grant (ML) and Academy of Finland (Finland) Postdoctoral research grant to ML (Decision No. 277121 to ML) are acknowledged.
Publisher Copyright:
© 2018
Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 2018/4/1
Y1 - 2018/4/1
N2 - 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.
AB - 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.
KW - Direct electron transfer
KW - Electrochemical synthesis of formate
KW - Enzyme electrode
KW - Heterodisulfide reductase
KW - Microbial electrosynthesis
UR - http://www.scopus.com/inward/record.url?scp=85043332945&partnerID=8YFLogxK
U2 - 10.1016/j.biortech.2018.01.036
DO - 10.1016/j.biortech.2018.01.036
M3 - Article
SN - 0960-8524
VL - 254
SP - 278
EP - 283
JO - Bioresource Technology
JF - Bioresource Technology
ER -