Microbial-Electrocatalytic Biofuel Production

Dr Singer and his lab are developing an integrated Microbial-ElectroCatalytic (MEC) system to produce advanced biofuels from H2/CO2. We have engineered Ralstonia eutropha, an aerobic chemolithoautotroph, to produce biofuel products by manipulating the polyhydroxybutyrate, fatty acid and isoprenoid biosynthesis pathways and we are testing novel reactor designs to generate these molecules from H2/CO2 at high titer.

We are also synthesizing defined inorganic electrocatalysts that generate H2 in neutral, aqueous conditions conducive to microbial growth. Strategies to tether these catalysts to electrode surfaces and to the surface of R. eutropha have been developed, and the targeted binding of inorganic complexes to the outer membrane of engineered R. eutropha strains has been demonstrated. Additionally, we have used heterogeneous catalysts to oligomerize 1-butanol to a mixtures of hydrocarbons that may be used as gasoline and jet fuel replacements. This work highlights the potential for combining synthetic biological and chemical approaches to produce biofuels.