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Title: RNAi assisted genome evolution unveils yeast mutants with improved xylose utilization

Abstract

Xylose is a major component of lignocellulosic biomass, one of the most abundant feedstocks for biofuel production. Therefore, efficient and rapid conversion of xylose to ethanol is crucial in the viability of lignocellulosic biofuel plants. In this study, RNAi Assisted Genome Evolution (RAGE) was used to improve the xylose utilization rate in SR8, one of the most efficient publicly available xylose utilizing Saccharomyces cerevisiae strains. To identify gene targets for further improvement, we created a genome-scale library consisting of both genetic over-expression and down-regulation mutations in SR8. Followed by screening in media containing xylose as the sole carbon source, yeast mutants with 29% faster xylose utilization, and 45% higher ethanol productivity were obtained relative to the parent strain. Two known and two new effector genes were identified in these mutant strains. Notably, down-regulation of CDC11, an essential gene, resulted in faster xylose utilization, and this gene target cannot be identified in genetic knock-out screens.

Authors:
ORCiD logo [1]; ORCiD logo [2];  [3]; ORCiD logo [4]
  1. Univ. of Illinois, Urbana-Champaign, IL (United States). Dept. of Chemical and Biomolecular Engineering, Carl R. Woese Inst. for Genomic Biology
  2. Univ. of Illinois, Urbana-Champaign, IL (United States). Dept. of Chemical and Biomolecular Engineering, Carl R. Woese Inst. for Genomic Biology; Zhejiang Univ., Hangzhou (China). College of Chemical and Biological Engineering
  3. Univ. of Illinois, Urbana-Champaign, IL (United States). Dept. of Agricultural and Biological Engineering
  4. Department of Chemical and Biomolecular Engineering, Carl R. Woese Institute for Genomic Biology, Urbana Illinois; Departments of Chemistry Biochemistry and Bioengineering, University of Illinois at Urbana, Urbana Illinois
Publication Date:
Research Org.:
Univ. of Illinois at Urbana-Champaign, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23)
Contributing Org.:
Center for Advanced Bioenergy and Bioproducts Innovation(CABBI)
OSTI Identifier:
1487105
Alternate Identifier(s):
OSTI ID: 1426314
Grant/Contract Number:  
SC0018420
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Biotechnology and Bioengineering
Additional Journal Information:
Journal Volume: 115; Journal Issue: 6; Related Information: Supporting information may be downloaded using the following link: https://onlinelibrary.wiley.com/doi/full/10.1002/bit.26570; Journal ID: ISSN 0006-3592
Publisher:
Wiley
Country of Publication:
United States
Language:
English
Subject:
09 BIOMASS FUELS; biofuels; genome engineering; xylose utilization

Citation Formats

HamediRad, Mohammad, Lian, Jiazhang, Li, Hejun, and Zhao, Huimin. RNAi assisted genome evolution unveils yeast mutants with improved xylose utilization. United States: N. p., 2018. Web. doi:10.1002/bit.26570.
HamediRad, Mohammad, Lian, Jiazhang, Li, Hejun, & Zhao, Huimin. RNAi assisted genome evolution unveils yeast mutants with improved xylose utilization. United States. doi:10.1002/bit.26570.
HamediRad, Mohammad, Lian, Jiazhang, Li, Hejun, and Zhao, Huimin. Tue . "RNAi assisted genome evolution unveils yeast mutants with improved xylose utilization". United States. doi:10.1002/bit.26570.
@article{osti_1487105,
title = {RNAi assisted genome evolution unveils yeast mutants with improved xylose utilization},
author = {HamediRad, Mohammad and Lian, Jiazhang and Li, Hejun and Zhao, Huimin},
abstractNote = {Xylose is a major component of lignocellulosic biomass, one of the most abundant feedstocks for biofuel production. Therefore, efficient and rapid conversion of xylose to ethanol is crucial in the viability of lignocellulosic biofuel plants. In this study, RNAi Assisted Genome Evolution (RAGE) was used to improve the xylose utilization rate in SR8, one of the most efficient publicly available xylose utilizing Saccharomyces cerevisiae strains. To identify gene targets for further improvement, we created a genome-scale library consisting of both genetic over-expression and down-regulation mutations in SR8. Followed by screening in media containing xylose as the sole carbon source, yeast mutants with 29% faster xylose utilization, and 45% higher ethanol productivity were obtained relative to the parent strain. Two known and two new effector genes were identified in these mutant strains. Notably, down-regulation of CDC11, an essential gene, resulted in faster xylose utilization, and this gene target cannot be identified in genetic knock-out screens.},
doi = {10.1002/bit.26570},
journal = {Biotechnology and Bioengineering},
number = 6,
volume = 115,
place = {United States},
year = {Tue Mar 13 00:00:00 EDT 2018},
month = {Tue Mar 13 00:00:00 EDT 2018}
}

Journal Article:
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Works referenced in this record:

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