Xylose assimilation enhances the production of isobutanol in engineered Saccharomyces cerevisiae.

TitleXylose assimilation enhances the production of isobutanol in engineered Saccharomyces cerevisiae.
Publication TypeJournal Article
Year of Publication2020
AuthorsLane, S, Zhang, Y, Yun, EJu, Ziolkowski, L, Zhang, G, Jin, Y-S, Avalos, JL
JournalBiotechnol Bioeng
Volume117
Issue2
Pagination372-381
Date Published2020 02
ISSN1097-0290
Abstract

<p>Bioconversion of xylose-the second most abundant sugar in nature-into high-value fuels and chemicals by engineered Saccharomyces cerevisiae has been a long-term goal of the metabolic engineering community. Although most efforts have heavily focused on the production of ethanol by engineered S. cerevisiae, yields and productivities of ethanol produced from xylose have remained inferior as compared with ethanol produced from glucose. However, this entrenched focus on ethanol has concealed the fact that many aspects of xylose metabolism favor the production of nonethanol products. Through reduced overall metabolic flux, a more respiratory nature of consumption, and evading glucose signaling pathways, the bioconversion of xylose can be more amenable to redirecting flux away from ethanol towards the desired target product. In this report, we show that coupling xylose consumption via the oxidoreductive pathway with a mitochondrially-targeted isobutanol biosynthesis pathway leads to enhanced product yields and titers as compared to cultures utilizing glucose or galactose as a carbon source. Through the optimization of culture conditions, we achieve 2.6 g/L of isobutanol in the fed-batch flask and bioreactor fermentations. These results suggest that there may be synergistic benefits of coupling xylose assimilation with the production of nonethanol value-added products.</p>

DOI10.1002/bit.27202
Alternate JournalBiotechnol Bioeng
PubMed ID31631318
Grant ListDE-SC0018420 / / DOE Center for Advanced Bioenergy and Bioproducts Innovation / International
DE-SC0019363 / / DOE Center for Advanced Bioenergy and Bioproducts Innovation / International