Promoter engineering for microbial bio-alkane gas production.

Successful industrial biotechnological solutions to biofuels and other chemicals production rely on effective competition with existing lower-cost natural sources and synthetic chemistry approaches enabled by adopting low-cost bioreactors and processes. This is achievable by mobilizing as a next generation industrial chassis, which can be cultivated under non-sterile conditions. To increase the cost effectiveness of an existing sustainable low carbon bio-propane production strategy, we designed and screened a constitutive promoter library based on the known strong porin promoter from . Comparative studies were performed between and using the reporter gene red fluorescent protein (RFP). Later studies with a fatty acid photodecarboxylase-RFP fusion protein demonstrated tuneable propane production in and , with an ∼8-fold improvement in yield over comparable isopropyl-β-D-thiogalactoside-inducible systems. This novel set of promoters is a useful addition to the synthetic biology toolbox for future engineering of to make chemicals and fuels.