Biosynthesis of 2-phenylethanol from styrene using engineered Escherichia coli whole cells.

2-Phenylethanol, an aromatic alcohol with a rose scent, is widely used in the cosmetics, food, and pharmaceutical industries. We designed an efficient multi-enzyme cascade pathway for production of 2-phenylethanol from styrene as the substrate. Initially, 2-phenylethanol was produced by overexpression of styrene monooxygenase A (styA), styrene monooxygenase B (styB), styrene oxide isomerase (SOI), alcohol dehydrogenase (yahK), and glucose dehydrogenase (gdh) in Escherichia coli to give 6.28 mM 2-phenylethanol. Subsequently, plasmids with different copy numbers were employed to balance the expression of pathway enzymes to produce 10.28 mM 2-phenylethanol, resulting in a 63.7 % increase in the final yield. Furthermore, the pH and temperature of the whole-cell conversion reaction were optimized, the optimum pH and temperature are 7.5 and 35℃, respectively. Finally, whole-cell conversion experiment was conducted, and the production of 2-phenylethanol reached 48.17 mM within 10 h. This study provides a theoretical and practical foundation for production of 2-phenylethanol.