287850 Enhancement of H2 and CO2 Uptake for the Production of Biodiesel in Ralstonia Eutropha

Wednesday, October 31, 2012
Hall B (Convention Center )
Ryan Sullivan, Pin-Ching Maness, Carrie Eckert and Jianping Yu, Biosciences Center, National Renewable Energy Laboratory, Golden, CO

Ralstonia eutropha fixes CO2 through the Calvin-Benson-Bassham (CBB) cycle using electrons and energy obtained from the oxidation of H2.  Producing biodiesel-equivalent electrofuel from renewable CO2 and H2 has immense potential, especially if the fuel is compatible with the existing fuel infrastructure.  This research addressed enhanced H2 and CO2 substrate utilization by focusing on two strategies: (1) optimizing transcriptional regulations to afford over-expression of Ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO), the enzyme responsible for assimilation of CO2 into the CBB cycle; and (2) hydrogenase over-expression by introduction of additional copies of genes encoding a membrane-bound hydrogenase (MBH), a soluble hydrogenase (SH), and their maturation machinery to enhance oxidation of H2 to generate NAD(P)H and ATP, both are required for CO2 fixation.  Incorporation of these strategies into a single production R. eutropha strain had resulted in 6-fold improvement in CO2 fixation and 3-fold improvement in H2 uptake, in vitro, with the overarching goal of providing abundant reducing equivalents towards the economic production of biodiesel in R. eutropha.

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See more of this Session: Poster Session: Sustainability and Sustainable Biorefineries
See more of this Group/Topical: Sustainable Engineering Forum