Engineering a novel biosynthetic pathway in Escherichia coli for production of renewable ethylene glycol

ABSTRACT Ethylene glycol (EG) is an important commodity chemical with broad industrial applications. It is presently produced from petroleum or natural gas feedstocks in processes requiring consumption of significant quantities of non‐renewable resources. Here, we report a novel pathway for biosynthesis of EG from the renewable sugar glucose in metabolically engineered Escherichia coli. Serine‐to‐EG conversion was first achieved through a pathway comprising serine decarboxylase, ethanolamine oxidase, and glycolaldehyde reductase. Serine provision in E. coli was then enhanced by overexpression of the serine‐biosynthesis pathway. The integration of these two parts into the complete EG‐biosynthesis pathway in E. coli allowed for production of 4.1 g/L EG at a cumulative yield of 0.14 g‐EG/g‐glucose, establishing a foundation for a promising biotechnology. Biotechnol. Bioeng. 2016;113: 376–383. © 2015 Wiley Periodicals, Inc. A novel ethylene glycol (EG) biosynthetic pathway was engineered in bacterium in E. coli to achieve de novo production from renewable sugar glucose. The pathway includes the upstream part for serine biosynthesis and the downstream part for serine‐to‐EG conversion. Through metabolically engineering these two parts individually, we achieved production of 4.1 g/L EG at a yield of 0.14 g‐EG/g‐glucose.