Abstract

Sustainable biofuel production from renewable biomass will require the efficient and complete use of all abundant sugars in the plant cell wall. Using the cellulolytic fungus Neurospora crassa as a model, we identified a xylodextrin transport and consumption pathway required for its growth on hemicellulose. Reconstitution of this xylodextrin utilization pathway in Saccharomyces cerevisiae revealed that fungal xylose reductases act as xylodextrin reductases, producing xylosyl-xylitol oligomers as metabolic intermediates. These xylosyl-xylitol intermediates are generated by diverse fungi and bacteria, indicating that xylodextrin reduction is widespread in nature. Xylodextrins and xylosyl-xylitol oligomers are then hydrolyzed by two hydrolases to generate intracellular xylose and xylitol. Xylodextrin consumption using a xylodextrin transporter, xylodextrin reductases and tandem intracellular hydrolases in cofermentations with sucrose and glucose greatly expands the capacity of yeast to use plant cell wall-derived sugars and has the potential to increase the efficiency of both first-generation and next-generation biofuel production.

Article and author information

Author details

  1. Xin Li

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    Xin Li, A patent application related to some of the work presented here has been filed on behalf of the Regents of the University of California..
  2. Vivian Yaci Yu

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
  3. Yuping Lin

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
  4. Kulika Chomvong

    Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
  5. Raíssa Estrela

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
  6. Annsea Park

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
  7. Julie M Liang

    Department of Chemistry, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
  8. Elizabeth A Znameroski

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
  9. Joanna Feehan

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
  10. Soo Rin Kim

    Institute for Genomic Biology, University of Illinois, Urbana, United States
    Competing interests
    No competing interests declared.
  11. Yong-Su Jin

    Institute for Genomic Biology, University of Illinois, Urbana, United States
    Competing interests
    No competing interests declared.
  12. N Louise Glass

    Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    No competing interests declared.
  13. Jamie H D Cate

    Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
    For correspondence
    jcate@lbl.gov
    Competing interests
    Jamie H D Cate, A patent application related to some of the work presented here has been filed on behalf of the Regents of the University of California..

Copyright

© 2015, Li et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Xin Li
  2. Vivian Yaci Yu
  3. Yuping Lin
  4. Kulika Chomvong
  5. Raíssa Estrela
  6. Annsea Park
  7. Julie M Liang
  8. Elizabeth A Znameroski
  9. Joanna Feehan
  10. Soo Rin Kim
  11. Yong-Su Jin
  12. N Louise Glass
  13. Jamie H D Cate
(2015)
Expanding xylose metabolism in yeast for plant cell wall conversion to biofuels
eLife 4:e05896.
https://doi.org/10.7554/eLife.05896

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https://doi.org/10.7554/eLife.05896

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