Files
Abstract
Megasphaera elsdenii has the native ability to condense acetyl-CoA groups to efficiently generate C4 to C8 compounds from lactate and plant carbohydrates, including butyric (C4), valeric (C5), hexanoic (C6), and in some cases octanoic (C8) acids. Though its metabolism is not well understood, its genome is annotated to have a chain elongation pathway using acetyl-CoAs. M. elsdenii’s major fermentation products, including butyric and hexanoic acids, are precursors to medium chain length alcohols butanol and hexanol in many related organisms. As the carbon chain length increases for the corresponding alcohols, fuel properties improve, making hexanol an appealing target as a next-generation drop-in biofuel, and M. elsdenii serves as a potential platform organism for engineering its production. In this work, a deletion of a putative propionyl Coenzyme A transferase was constructed in the M. elsdenii chromosome, which resulted in a loss of propionate production as well as an overall increase of longer chain-length products.