skip to main content

DOE PAGESDOE PAGES

Title: Adaptation to low pH and lignocellulosic inhibitors resulting in ethanolic fermentation and growth of Saccharomyces cerevisiae

Here, lignocellulosic bioethanol from renewable feedstocks using Saccharomyces cerevisiae is a promising alternative to fossil fuels owing to environmental challenges. S. cerevisiae is frequently challenged by bacterial contamination and a combination of lignocellulosic inhibitors formed during the pre-treatment, in terms of growth, ethanol yield and productivity. We investigated the phenotypic robustness of a brewing yeast strain TMB3500 and its ability to adapt to low pH thereby preventing bacterial contamination along with lignocellulosic inhibitors by short-term adaptation and adaptive lab evolution (ALE). The short-term adaptation strategy was used to investigate the inherent ability of strain TMB3500 to activate a robust phenotype involving pre-culturing yeast cells in defined medium with lignocellulosic inhibitors at pH 5.0 until late exponential phase prior to inoculating them in defined media with the same inhibitor cocktail at pH 3.7. Adapted cells were able to grow aerobically, ferment anaerobically (glucose exhaustion by 19 +/- 5 h to yield 0.45 +/- 0.01 g ethanol g glucose -1) and portray significant detoxification of inhibitors at pH 3.7, when compared to non-adapted cells. ALE was performed to investigate whether a stable strain could be developed to grow and ferment at low pH with lignocellulosic inhibitors in a continuous suspension culture. Thoughmore » a robust population was obtained after 3600 h with an ability to grow and ferment at pH 3.7 with inhibitors, inhibitor robustness was not stable as indicated by the characterisation of the evolved culture possibly due to phenotypic plasticity. With further research, this short-term adaptation and low pH strategy could be successfully applied in lignocellulosic ethanol plants to prevent bacterial contamination.« less
Authors:
 [1] ;  [2] ;  [1] ;  [1]
  1. Lund Univ., Lund (Sweden)
  2. National Renewable Energy Lab. (NREL), Golden, CO (United States)
Publication Date:
Report Number(s):
NREL/JA-5100-67105
Journal ID: ISSN 2191-0855
Grant/Contract Number:
AC36-08GO28308
Type:
Accepted Manuscript
Journal Name:
AMB Express
Additional Journal Information:
Journal Volume: 6; Journal Issue: 1; Journal ID: ISSN 2191-0855
Publisher:
Springer
Research Org:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org:
Swedish National Energy Agency; USDOE
Country of Publication:
United States
Language:
English
Subject:
09 BIOMASS FUELS; Saccharomyces cerevisiae; low pH; lignocellulosic inhibitors; phenotypic robustness; adaptation; ethanol yield
OSTI Identifier:
1325063

Narayanan, Venkatachalam, Sànchez i Nogué, Violeta, van Niel, Ed W. J., and Gorwa-Grauslund, Marie F.. Adaptation to low pH and lignocellulosic inhibitors resulting in ethanolic fermentation and growth of Saccharomyces cerevisiae. United States: N. p., Web. doi:10.1186/s13568-016-0234-8.
Narayanan, Venkatachalam, Sànchez i Nogué, Violeta, van Niel, Ed W. J., & Gorwa-Grauslund, Marie F.. Adaptation to low pH and lignocellulosic inhibitors resulting in ethanolic fermentation and growth of Saccharomyces cerevisiae. United States. doi:10.1186/s13568-016-0234-8.
Narayanan, Venkatachalam, Sànchez i Nogué, Violeta, van Niel, Ed W. J., and Gorwa-Grauslund, Marie F.. 2016. "Adaptation to low pH and lignocellulosic inhibitors resulting in ethanolic fermentation and growth of Saccharomyces cerevisiae". United States. doi:10.1186/s13568-016-0234-8. https://www.osti.gov/servlets/purl/1325063.
@article{osti_1325063,
title = {Adaptation to low pH and lignocellulosic inhibitors resulting in ethanolic fermentation and growth of Saccharomyces cerevisiae},
author = {Narayanan, Venkatachalam and Sànchez i Nogué, Violeta and van Niel, Ed W. J. and Gorwa-Grauslund, Marie F.},
abstractNote = {Here, lignocellulosic bioethanol from renewable feedstocks using Saccharomyces cerevisiae is a promising alternative to fossil fuels owing to environmental challenges. S. cerevisiae is frequently challenged by bacterial contamination and a combination of lignocellulosic inhibitors formed during the pre-treatment, in terms of growth, ethanol yield and productivity. We investigated the phenotypic robustness of a brewing yeast strain TMB3500 and its ability to adapt to low pH thereby preventing bacterial contamination along with lignocellulosic inhibitors by short-term adaptation and adaptive lab evolution (ALE). The short-term adaptation strategy was used to investigate the inherent ability of strain TMB3500 to activate a robust phenotype involving pre-culturing yeast cells in defined medium with lignocellulosic inhibitors at pH 5.0 until late exponential phase prior to inoculating them in defined media with the same inhibitor cocktail at pH 3.7. Adapted cells were able to grow aerobically, ferment anaerobically (glucose exhaustion by 19 +/- 5 h to yield 0.45 +/- 0.01 g ethanol g glucose-1) and portray significant detoxification of inhibitors at pH 3.7, when compared to non-adapted cells. ALE was performed to investigate whether a stable strain could be developed to grow and ferment at low pH with lignocellulosic inhibitors in a continuous suspension culture. Though a robust population was obtained after 3600 h with an ability to grow and ferment at pH 3.7 with inhibitors, inhibitor robustness was not stable as indicated by the characterisation of the evolved culture possibly due to phenotypic plasticity. With further research, this short-term adaptation and low pH strategy could be successfully applied in lignocellulosic ethanol plants to prevent bacterial contamination.},
doi = {10.1186/s13568-016-0234-8},
journal = {AMB Express},
number = 1,
volume = 6,
place = {United States},
year = {2016},
month = {8}
}

Works referenced in this record:

Increased tolerance and conversion of inhibitors in lignocellulosic hydrolysates by Saccharomyces cerevisiae
journal, January 2007
  • Almeida, Joao; Modig, Tobias; Petersson, Anneli
  • Journal of Chemical Technology & Biotechnology, Vol. 82, Issue 4, p. 340-349
  • DOI: 10.1002/jctb.1676

Inhibition of ethanol-producing yeast and bacteria by degradation products produced during pre-treatment of biomass
journal, August 2004
  • Klinke, H. B.; Thomsen, A. B.; Ahring, B. K.
  • Applied Microbiology and Biotechnology, Vol. 66, Issue 1, p. 10-26
  • DOI: 10.1007/s00253-004-1642-2

Fermentation of lignocellulosic hydrolysates. II: inhibitors and mechanisms of inhibition
journal, August 2000

A 5-hydroxymethyl furfural reducing enzyme encoded by theSaccharomyces cerevisiae ADH6 gene conveys HMF tolerance
journal, January 2006
  • Petersson, Anneli; Almeida, João R. M.; Modig, Tobias
  • Yeast, Vol. 23, Issue 6, p. 455-464
  • DOI: 10.1002/yea.1370