Construction of novel Saccharomyces cerevisiae strains for bioethanol active dry yeast (ADY) production

PLoS One. 2013 Dec 23;8(12):e85022. doi: 10.1371/journal.pone.0085022. eCollection 2013.

Abstract

The application of active dry yeast (ADY) in bioethanol production simplifies operation processes and reduces the risk of bacterial contamination. In the present study, we constructed a novel ADY strain with improved stress tolerance and ethanol fermentation performances under stressful conditions. The industrial Saccharomyces cerevisiae strain ZTW1 showed excellent properties and thus subjected to a modified whole-genome shuffling (WGS) process to improve its ethanol titer, proliferation capability, and multiple stress tolerance for ADY production. The best-performing mutant, Z3-86, was obtained after three rounds of WGS, producing 4.4% more ethanol and retaining 2.15-fold higher viability than ZTW1 after drying. Proteomics and physiological analyses indicated that the altered expression patterns of genes involved in protein metabolism, plasma membrane composition, trehalose metabolism, and oxidative responses contribute to the trait improvement of Z3-86. This work not only successfully developed a novel S. cerevisiae mutant for application in commercial bioethanol production, but also enriched the current understanding of how WGS improves the complex traits of microbes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biofuels*
  • Dehydration
  • Ethanol / metabolism*
  • Fermentation / physiology
  • Gene Expression Regulation, Fungal / genetics
  • Gene Expression Regulation, Fungal / physiology
  • Industrial Microbiology / methods*
  • Proteomics
  • Real-Time Polymerase Chain Reaction
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae / physiology
  • Species Specificity
  • Stress, Physiological / genetics*

Substances

  • Biofuels
  • Ethanol

Grants and funding

This work was financially supported by Postdoctoral Science Foundation of China (2013M531450; http://res.chinapostdoctor.org.cn/Program/Main.html), Zhejiang Province Postdoctoral Foundation (BSH1301026; http://www.zjhrss.gov.cn/), and State Key Laboratory of Motor Vehicle Biofuels Technology of China (2013013; http://www.tianguan.com.cn/jituan/index.asp). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.