Metabolic engineering of Escherichia coli for production of 2‐Phenylethylacetate from L‐phenylalanine

In order to meet the need of consumer preferences for natural flavor compounds, microbial synthesis method has become a very attractive alternative to the chemical production. The 2‐phenylethanol (2‐PE) and its ester 2‐phenylethylacetate (2‐PEAc) are two extremely important flavor compounds with a rose‐like odor. In recent years, Escherichia coli and yeast have been metabolically engineered to produce 2‐PE. However, a metabolic engineering approach for 2‐PEAc production is rare. Here, we designed and expressed a 2‐PEAc biosynthetic pathway in E. coli. This pathway comprised four steps: aminotransferase (ARO8) for transamination of L‐phenylalanine to phenylpyruvate, 2‐keto acid decarboxylase KDC for the decarboxylation of the phenylpyruvate to phenylacetaldehyde, aldehyde reductase YjgB for the reduction of phenylacetaldehyde to 2‐PE, alcohol acetyltransferase ATF1 for the esterification of 2‐PE to 2‐PEAc. Using the engineered E. coli strain for shake flasks cultivation with 1 g/L L‐phenylalanine, we achieved co‐production of 268 mg/L 2‐PEAc and 277 mg/L 2‐PE. Our results suggest that approximately 65% of L‐phenylalanine was utilized toward 2‐PEAc and 2‐PE biosynthesis and thus demonstrate potential industrial applicability of this microbial platform.