Microbial production of fatty acids has been proposed as a renewable means of biofuel production, and more recently has been explored as a source of commodity chemicals for the production of polymers, detergents, lubricants, and other industrial products. We have therefore investigated several enzymatic systems to modify the structures of fatty acids produced in E. coli, and tailor their functionalities for specific industrial applications.
First, we have engineered E. coli to produce branched fatty acids and demonstrated that the branching pattern is controlled by the availability of branched amino acids in the cell. We leveraged this observation to specifically produce anteiso-branched fatty acids that possess significantly lower melting points than straight-chain isomers. This reduced melting point will improve the quality of fuels derived from these compounds. Additionally, we have investigated the use of a bacterial cytochrome P450 enzyme to produce w-hydroxy fatty acids de novo from glucose. These compounds can be polymerized into a variety of bioplastics. Finally, we are currently establishing novel pathways towards long chain dicarboxylic acids and diols that are used in the production of plastics, polyesters and nylons. Taken together, the systems described above will expand the utility of microbes to renewably produce valuable chemicals that would otherwise come from petroleum.