Metabolic Engineering of the Oleaginous Yeast Yarrowia Lipolytica for 2-Phenylethanol Overproduction

The rose fragrance molecule 2-phenylethanol (2-PE) has huge market demand in the cosmetics, food and pharmaceutical industries. However, current 2-PE synthesis methods do not meet the efficiency market requirement. In this study, CRISPR-Cas9-related metabolic engineering strategies were applied to Yarrowia lipolytica for the de novo biosynthesis of 2-PE. Initially, overexpressing exogenous feedback-resistant EcAROGfbr and EcPheAfbr increased 2-PE production to 276.3 mg/L. Subsequently, the ylARO10 and ylPAR4 from endogenous genes were enhanced with the multi-copies to increase the titer to 605 mg/L. Knockout of ylTYR1 and enhancement of shikimate pathway by removing the precursor metabolic bottleneck and overexpressing the genes ylTKT, ylARO1, and ylPHA2 resulted in a significant increase of the 2-PE titer to 2.4 g/L at 84 h, with the yield of 0.06 g/gglu, which is the highest yield for de novo synthesis in yeast. This study provides a valuable precedent for the efficient biosynthesis of shikimate pathway derivatives.