When considering the bioproduction of fuels, the researchers looked at the alternatives. Propane is cheaper and easier to condense into liquid than other available gaseous fuels, such as hydrogen. And it's arguably a better synthetic candidate than liquid fuels which can be detrimental to their living bacterial factories and require purification from the host once produced.

With the premise of producing a fuel that's more sustainable in a biological host and easier to bring to market, the research team engineered a pathway in E. coli that interrupts the conversion of fatty acids into cell membranes and instead couples naturally unlinked enzymatic processes to manufacture propane.