Production of Vehicle Fuel Precursors from Co-cultures of Shewanella and Synechococcus
Long-chain Hydrocarbons from Synechococcus and Shewanella
A method to directly synthesize long-chain (C25-C31) hydrocarbons directly from sunlight, water, and CO2 using co-cultured microbes has been developed. These hydrocarbons may be further processed into vehicle fuels using traditional oil refining techniques. This process eliminates the costs and challenges associated with obtaining, transporting, and processing cellulosic feedstocks into vehicle fuels. One of the microbes is Synechococcus, a naturally occurring Cyanobacterium that takes sunlight, carbon dioxide, and water and creates carbon-based food molecules for the second culture. The second microbe is Shewanella, which converts the food into more complex hydrocarbons. The two organisms have evolved naturally as symbiotic co-cultures and do not require genetic engineering to be compatible.
Optimizing Vehicle Fuel Precursors
The Shewanella bacteria naturally produce hydrocarbons but the University of Minnesota clarified the key protein responsible for fuel production, OleA and recently obtained the proteins’s crystal structure. Based on this knowledge, experiments are currently in process to optimize fuel production through both metabolic engineering and optimization of OleA.
FEATURES AND BENEFITS OF USING SHEWANELLA AND SYNECHOCOCCUS TO PRODUCE VEHICLE FUEL PRECURSORS:
- Synthesizes long-chain hydrocarbons directly from sunlight, water, and CO2, without cellulosic feedstock, using co-cultured microbes
- Lower capital and operating expense.
- Higher energy content in resulting vehicle fuels compared to ethanol
- Minimal processing steps
- Funded through an ARPA-E grant
- Avoids reliance on large amounts of agricultural land and uses carbon dioxide as a feedstock
