Microbial ElectroCatalytic (MEC) Biofuel Production

  • Steven W. Singer
  • Harry R. Beller
  • Swapnil Chhabra
  • Christopher J. Chang
  • Jerry Adler


We are developing an integrated Microbial-ElectroCatalytic (MEC) ­system consisting of Ralstonia eutropha as a chemolithoautotrophic host for metabolic engineering coupled to a small-molecule electrocatalyst for the production of biofuels from CO2 and H2. R. eutropha is an aerobic bacterium that grows with CO2 as the carbon source and H2 as electron donor while producing copious amounts of polyhydroxybutyrate. Metabolic flux from existing R. eutropha pathways is being diverted into engineered pathways that produce biofuels. Novel molybdenum electrocatalysts that can convert water to hydrogen in neutral aqueous media will act as chemical mediators to generate H2 from electrodes in the presence of engineered strains of R. eutropha. To increase the local concentration of H2, we are engineering R. eutropha’s outer-membrane proteins to tether the electrocatalysts to the bacterial surface. The integrated MEC system will provide a transformational new source of renewable liquid transportation fuels that extends beyond biomass-derived substrates.


Metabolic Engineering Synthetic Biology Biofuel Production Heterologous Pathway Liquid Transportation Fuel 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This work is funded by the ARPA-E Electrofuels program. We would also like to thank the Joint BioEnergy Institute (JBEI) for the use of its facilities and equipment; JBEI is supported by the Office of Science, Office of Biological and Environmental Research, of the U.S. Department of Energy. Work at Lawrence Berkeley National Laboratory is performed under the auspices of the U.S. Department of Energy through contract DE-AC02-05CH11231.


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • Steven W. Singer
    • 1
  • Harry R. Beller
    • 1
  • Swapnil Chhabra
    • 2
  • Christopher J. Chang
    • 3
  • Jerry Adler
    • 4
  1. 1.Earth Sciences DivisionLawrence Berkeley National LaboratoryBerkeleyUSA
  2. 2.Physical Biosciences DivisionLawrence Berkeley National LaboratoryBerkeleyUSA
  3. 3.Department of ChemistryUniversity of California-BerkeleyBerkeleyUSA
  4. 4.Logos TechnologiesArlingtonUSA

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