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Engineering of Pentose Transport in Saccharomyces cerevisiae for Biotechnological Applications

Lignocellulosic biomass yields after hydrolysis, besides the hexose D-glucose, D-xylose, and L-arabinose as main pentose sugars. In second generation bioethanol production utilizing the yeast Saccharomyces cerevisiae, it is critical that all three sugars are co-consumed to obtain an economically fea...

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Autores principales: Nijland, Jeroen G., Driessen, Arnold J. M.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2020
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7000353/
https://www.ncbi.nlm.nih.gov/pubmed/32064252
http://dx.doi.org/10.3389/fbioe.2019.00464
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author Nijland, Jeroen G.
Driessen, Arnold J. M.
author_facet Nijland, Jeroen G.
Driessen, Arnold J. M.
author_sort Nijland, Jeroen G.
collection PubMed
description Lignocellulosic biomass yields after hydrolysis, besides the hexose D-glucose, D-xylose, and L-arabinose as main pentose sugars. In second generation bioethanol production utilizing the yeast Saccharomyces cerevisiae, it is critical that all three sugars are co-consumed to obtain an economically feasible and robust process. Since S. cerevisiae is unable to metabolize pentose sugars, metabolic pathway engineering has been employed to introduce the respective pathways for D-xylose and L-arabinose metabolism. However, S. cerevisiae lacks specific pentose transporters, and these sugars enter the cell with low affinity via glucose transporters of the Hxt family. Therefore, in the presence of D-glucose, utilization of D-xylose and L-arabinose is poor as the Hxt transporters prefer D-glucose. To solve this problem, heterologous expression of pentose transporters has been attempted but often with limited success due to poor expression and stability, and/or low turnover. A more successful approach is the engineering of the endogenous Hxt transporter family and evolutionary selection for D-glucose insensitive growth on pentose sugars. This has led to the identification of a critical and conserved asparagine residue in Hxt transporters that, when mutated, reduces the D-glucose affinity while leaving the D-xylose affinity mostly unaltered. Likewise, mutant Gal2 transporter have been selected supporting specific uptake of L-arabinose. In fermentation experiments, the transporter mutants support efficient uptake and consumption of pentose sugars, and even co-consumption of D-xylose and D-glucose when used at industrial concentrations. Further improvements are obtained by interfering with the post-translational inactivation of Hxt transporters at high or low D-glucose concentrations. Transporter engineering solved major limitations in pentose transport in yeast, now allowing for co-consumption of sugars that is limited only by the rates of primary metabolism. This paves the way for a more economical second-generation biofuels production process.
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spelling pubmed-70003532020-02-14 Engineering of Pentose Transport in Saccharomyces cerevisiae for Biotechnological Applications Nijland, Jeroen G. Driessen, Arnold J. M. Front Bioeng Biotechnol Bioengineering and Biotechnology Lignocellulosic biomass yields after hydrolysis, besides the hexose D-glucose, D-xylose, and L-arabinose as main pentose sugars. In second generation bioethanol production utilizing the yeast Saccharomyces cerevisiae, it is critical that all three sugars are co-consumed to obtain an economically feasible and robust process. Since S. cerevisiae is unable to metabolize pentose sugars, metabolic pathway engineering has been employed to introduce the respective pathways for D-xylose and L-arabinose metabolism. However, S. cerevisiae lacks specific pentose transporters, and these sugars enter the cell with low affinity via glucose transporters of the Hxt family. Therefore, in the presence of D-glucose, utilization of D-xylose and L-arabinose is poor as the Hxt transporters prefer D-glucose. To solve this problem, heterologous expression of pentose transporters has been attempted but often with limited success due to poor expression and stability, and/or low turnover. A more successful approach is the engineering of the endogenous Hxt transporter family and evolutionary selection for D-glucose insensitive growth on pentose sugars. This has led to the identification of a critical and conserved asparagine residue in Hxt transporters that, when mutated, reduces the D-glucose affinity while leaving the D-xylose affinity mostly unaltered. Likewise, mutant Gal2 transporter have been selected supporting specific uptake of L-arabinose. In fermentation experiments, the transporter mutants support efficient uptake and consumption of pentose sugars, and even co-consumption of D-xylose and D-glucose when used at industrial concentrations. Further improvements are obtained by interfering with the post-translational inactivation of Hxt transporters at high or low D-glucose concentrations. Transporter engineering solved major limitations in pentose transport in yeast, now allowing for co-consumption of sugars that is limited only by the rates of primary metabolism. This paves the way for a more economical second-generation biofuels production process. Frontiers Media S.A. 2020-01-29 /pmc/articles/PMC7000353/ /pubmed/32064252 http://dx.doi.org/10.3389/fbioe.2019.00464 Text en Copyright © 2020 Nijland and Driessen. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Bioengineering and Biotechnology
Nijland, Jeroen G.
Driessen, Arnold J. M.
Engineering of Pentose Transport in Saccharomyces cerevisiae for Biotechnological Applications
title Engineering of Pentose Transport in Saccharomyces cerevisiae for Biotechnological Applications
title_full Engineering of Pentose Transport in Saccharomyces cerevisiae for Biotechnological Applications
title_fullStr Engineering of Pentose Transport in Saccharomyces cerevisiae for Biotechnological Applications
title_full_unstemmed Engineering of Pentose Transport in Saccharomyces cerevisiae for Biotechnological Applications
title_short Engineering of Pentose Transport in Saccharomyces cerevisiae for Biotechnological Applications
title_sort engineering of pentose transport in saccharomyces cerevisiae for biotechnological applications
topic Bioengineering and Biotechnology
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7000353/
https://www.ncbi.nlm.nih.gov/pubmed/32064252
http://dx.doi.org/10.3389/fbioe.2019.00464
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