The team of Distinguished Professor Sang Yup Lee of the Department of Chemical and Biomolecular Engineering produced aromatic polyesters from Escherichia coli (E. coli) strains by employing direct microbial fermentation from renewable feedstock carbohydrates. Conventionally, aromatic polyesters boast solid strength and heat stability and accordingly there has been a great deal of interest in fermentative production of aromatic polyesters from renewable non-food biomass, but without success.
However, aromatic polyesters are only made by feeding the cells with corresponding aromatic monomers as substrates, and have not been produced by direct fermentation from renewable feedstock carbohydrates such as glucose.
To address this issue, the team developed a detailed procedure for aromatic polyester production through identifying CoA-transferase, which activates phenylalkanoates into their corresponding CoA derivatives. In this process, researchers employed metabolic engineering of E. coli to produce phenylalkanoates from glucose based on a genome-scale metabolic flux analysis. In particular, Professor Sang Yup Lee’s research team modulated gene expression to produce various aromatic polyesters having different monomer fractions.
The research team successfully produced aromatic polyesters, non-natural polymers, using a strategy that combines systems metabolic engineering and synthetic biology. They succeeded in biosynthesis of various kinds of aromatic polyesters through the system, thus proving the technical excellence of the environmentally friendly biosynthetic system developed in this research. Furthermore, his team also demonstrated the potential of expanding the range of aromatic polyesters from renewable resources, which are expected to play an important role in the bio-plastic industry.