Cosynthesis of l-homophenylalanine and 2-phenylethanol by recombinant Saccharomyces cerevisiae expressing aspartate aminotransferase from Escherichia coli BL21(DE3)

Abstract

The Escherichia coli aspartate aminotransferase gene was introduced into a high 2-phenylethanol (2-PEA) producing Saccharomyces cerevisiae YS58, and the recombinant strain of S. cerevisiae was utilized for the co-production of 2-PEA and l-homophenylalanine (L-HPA) via a fermentation process. The L-HPA productivity of the recombinant S. cerevisiae improved 78.9% in comparison to the wild-type S. cerevisiae. High yields of 43.7 mM L-HPA and 32.4 mM 2-PEA were achieved. As a result, the coupling of the biosynthesis process for these two products in the recombinant strain led to a more complete and efficient utilization of the substrate, l-phenylalanine.

Keywords: 2-Phenylethanol; Aspartate aminotransferase; Cosynthesis; Saccharomyces cerevisiae; l-Homophenylalanine.