An Orthogonal and pH-Tunable Sensor-Selector for Muconic Acid Biosynthesis in Yeast

作者:Snoek Tim; Romero Suarez David; Zhang Jie; Ambri Francesca; Skjoedt Mette L; Sudarsan Suresh; Jensen Michael K*; Keasling Jay D
来源:ACS Synthetic Biology, 2018, 7(4): 995-1003.
DOI:10.1021/acssynbio.7b00439

摘要

Microbes offer enormous potential for production of industrially relevant chemicals and therapeutics, yet the rapid identification of high-producing microbes from large genetic libraries is a major bottleneck in modern cell factory development. Here, we develop and apply a synthetic selection system in Saccharomyces cerevisiae that couples the concentration of muconic acid, a plastic precursor, to cell fitness by using the prokaryotic transcriptional regulator BenM driving an antibiotic resistance gene. We show that the sensor-selector does not affect production nor fitness, and find that tuning pH of the cultivation medium limits the rise of nonproducing cheaters. We apply the sensor-selector to selectively enrich for best-producing variants out of a large library of muconic acid production strains, and identify an isolate that produces more than 2 g/L muconic acid in a bioreactor. We expect that this sensor-selector can aid the development of other synthetic selection systems based on allosteric transcription factors.

  • 出版日期2018-4