Fluctuations in glucose availability prevent global proteome changes and physiological transition during prolonged chemostat cultivations of S. cerevisiae

Naia Risager Wright*, Tune Wulff, Eva Akke Palmqvist, Thomas Rubæk Jørgensen, Christopher T. Workman, Nikolaus Sonnenschein, Nanna Petersen Rønnest, Markus J. Herrgård

*Corresponding author for this work

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

Chemostat cultivation mode imposes selective pressure on cells, which may result in slow adaptation in the physiological state over time. We applied a two-compartment scale-down chemostat system imposing feast-famine conditions to characterize the long-term (100's of hours) response of S. cerevisiae to fluctuating glucose availability. A wild-type strain and a recombinant strain, expressing an insulin precursor, were cultured in the scale-down system, and analyzed at the physiological and proteomic level. Phenotypes of both strains were compared to those observed in a well-mixed chemostat. Our results show that S. cerevisiae subjected to long term chemostat conditions undergoes a global reproducible shift in its cellular state and that this transition occurs faster and is larger in magnitude for the recombinant strain including a significant decrease in the expression of the insulin product. We find that the transition can be completely avoided in the presence of fluctuations in glucose availability as the strains subjected to feast-famine conditions under otherwise constant culture conditions exhibited constant levels of the measured proteome for over 250 hours. We hypothesize possible mechanisms responsible for the observed phenotypes and suggest experiments that could be used to test these mechanisms. This article is protected by copyright. All rights reserved.
Original languageEnglish
JournalBiotechnology and Bioengineering
Volume117
Issue number7
Pages (from-to)2074-2088
Number of pages15
ISSN0006-3592
DOIs
Publication statusPublished - 2020

Keywords

  • S. cerevisiae
  • Scale-down
  • Proteome
  • Heterologous protein
  • Feast-famine conditions

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