Exploiting xylose metabolism for the efficient production of biofuels
and chemicals by engineered Saccharomyces cerevisiae
Abstract
Microbial conversion of plant biomass into fuels and chemicals offers a
practical solution to global concerns on limited natural resources,
environmental pollution, and climate change. Pursuant to these goals,
researchers have put tremendous efforts and resources towards
engineering the yeast Saccharomyces cerevisiae to efficiently
convert xylose, the second most abundant sugar in lignocellulosic
biomass, into various fuels and chemicals. Although many challenges
remain, these research investments have facilitated efficient and rapid
fermentation of xylose, simultaneous co-consumption of xylose with
carbon sources in lignocellulosic hydrolysates, and enhanced production
of a wide range of valuable chemicals from xylose. In particular,
understanding of xylose-induced metabolic rewiring in engineered yeast
has stimulated the use of xylose as a preferred carbon source for the
production of various non-ethanol bioproducts. Here, we summarize recent
advances in metabolic engineering in yeast to address bottlenecks of
xylose assimilation, and to enable simultaneous co-utilization of xylose
and other cellulosic carbon sources. We also highlight distinct
characteristics of xylose metabolism which can be harnessed for the
production of advanced biofuels and chemicals.