Engineering of Saccharomyces cerevisiae for the efficient co-utilization of glucose and xylose

Abstract

The rapid co-fermentation of both glucose and xylose is important for the efficient conversion of lignocellulose biomass into fuels and chemicals. Saccharomyces cerevisiae is considered to be a potential cell factory and has been used to produce various fuels and chemicals, but it cannot metabolize xylose, which has greatly limited the utilization of lignocellulose materials. Therefore, numerous studies have attempted to develop xylose fermenting strains in past decades. The simple introduction of the xylose metabolic pathway does not enable yeast to rapidly utilize xylose, and several limitations still need to be addressed, including glucose repression and slow xylose transport, cofactor imbalance in the xylose reductase/xylitol dehydrogenase pathway, functional expression of a heterologous xylose isomerase, the low efficiency of downstream pathways and low ethanol production. In this review, we will discuss strategies to overcome these limitations and the recent progress in engineering xylose fermenting S. cerevisiae strains.

Keywords: Saccharomyces cerevisiae; lignocellulosic ethanol fermentation; xylose.