A xylose-utilizing Saccharomyces cerevisiae strain serves as a better
host for producing acetyl-CoA derived n-butanol
Abstract
Efficient xylose catabolism in engineered Saccharomyces cerevisiae
enables more economical lignocellulosic biorefinery with improved
production yields per unit of biomass. Yet, the product profile of
glucose/xylose co-fermenting S. cerevisiae is mainly limited to
bioethanol and a few other chemicals. Here, we introduced an
n-butanol-biosynthesis pathway into a glucose/xylose co-fermenting S.
cerevisiae strain (XUSEA) to evaluate its potential on the production of
acetyl-CoA derived products. Higher n-butanol production of
glucose/xylose co-fermenting strain was explained by the transcriptomic
landscape, which revealed strongly increased acetyl-CoA and NADPH pools
when compared to a glucose fermenting wild-type strain. The acetate
supplementation expected to support acetyl-CoA pool further increased
n-butanol production, which was also validated during the fermentation
of lignocellulosic hydrolysates containing acetate. Our findings imply
the feasibility of lignocellulosic biorefinery for producing fuels and
chemicals derived from a key intermediate of acetyl-CoA through
glucose/xylose co-fermentation.