Researchers Develop Propane-Producing Escherichia coli

Propane is a major component of liquid petroleum gas (LPG) derived from fossil fuels commonly used in vehicles and cooking. With the concerns on fossil fuel depletion, searching for a renewable source of propane is imperative. Lei Zhang and researchers from the Chinese Academy of Sciences now report the construction of a novel propane biosynthetic pathway in Escherichia coli.

The team constructed a valine pathway into an E. coli strain BW25113 (DE3) Δ13 through genetic engineering, enabling them to produce isobutyraldehyde, a precursor of propane. These strains then achieved propane synthesis by connecting the engineered valine pathway and cyanobacterial aldehyde-deformylating oxygenase (ADO). After screening several mutants, the team identified two ADO mutants that exhibited high catalytic activity for isobutyraldehyde and had improved propane productivity.

The propane pathway constructed through the engineered valine pathway can produce enough isobutyraldehyde for propane production. These results reveal the potential for developing a microbial manufacturing platform for propane.