De novo biosynthesis of 2-phenylethanol in engineered Pichia pastoris.

2-Phenylethanol (2-PE) is an important flavour and fragrance compound with a rose-like odor, which is widely used in cosmetics and food industries. Natural 2-PE is costly and cannot meet the market demand due to the relative low content of 2-PE in the plants. Thus, there is an increasing interest in the search for alternative routes for 2-PE production. Here we demonstrate the engineering of Pichia pastoris to produce 2-PE directly from simple sugars for the first time. We first demonstrated that improving downstream pathway from phenylpyruvate to 2-PE by overexpressing ARO10 and ADH6 could increase the biosynthesis of 2-PE. Then several genetic engineering strategies were developed to increase phenylpyruvate availability to improve 2-PE production. 1169 mg/L of 2-PE was accumulated in the final engineered strain. This study showed the potential of P. pastoris as a host strain to produce industrially interested 2-PE by metabolic engineering.