Microbial production of short-chain-length-co-medium-chain-length polyhydroxyalkanoate (SCL-MCL PHA)

Abstract

The concerns toward plastic waste and fossil fuel usage have brought interest in production of biodegradable plastic. Due to the recent development of systems metabolic engineering tools, microbial hosts have been engineered for polymer production. First, we showed production of PHAs can be achieved by Aeromonas hydrophila from plant oil. In this study emulsification and hydrolysis of plant oil has been conducted. After various optimization of cultivation, the final optimization condition Aeromonas hydrophila produced SCL-MCL PHAs (14.08g/L), which is the first production of Aeromonas hydrophila SCL-MCL PHAs from waste oil. Next, the development of Escherichia coli was conducted for SCL-MCL PHAs from glucose. Glucose is a cheap and soluble carbon source allowing high cell density culture. Here, we constructed a reverse β-oxidation pathway for production of PHAs from glucose. As a result, we developed SCL-MCL PHAs producing strain with 3.1 mol% of MCL monomer compositions. The recombinant strains developed and physical and chemical treatment of carbon source will help one-step closer to bio-based production of polymers.