Engineering Yeast Transcription Machinery for Improved Ethanol Tolerance and Production

Abstract

Global transcription machinery engineering (gTME) is an approach for reprogramming gene transcription to elicit cellular phenotypes important for technological applications. Here we show the application of gTME to Saccharomyces cerevisiae for improved glucose/ethanol tolerance, a key trait for many biofuels programs. Mutagenesis of the transcription factor Spt15p and selection led to dominant mutations that conferred increased tolerance and more efficient glucose conversion to ethanol. The desired phenotype results from the combined effect of three separate mutations in the SPT15 gene [serine substituted for phenylalanine (Phe(177)Ser) and, similarly, Tyr(195)His, and Lys(218)Arg]. Thus, gTME can provide a route to complex phenotypes that are not readily accessible by traditional methods.

Biofuel alternatives to ethanol: pumping the microbial well

“…This knowledge is poised for use in the systematic design of highly efficient biofuel production pathways. This global approach is nicely illustrated by recent publications showing the effect of various transcription factors on ethanol tolerance and production in E. coli and S. cerevisiae [68,69].…”

Genome‐wide identification of tolerance mechanisms toward p‐coumaric acid in Pseudomonas putida

“…However, it still faces some challenges, such as ameliorating the toxic effects of intermediates and products of interest (Keasling, 2010). Numerous studies have focused on increasing the tolerance of different production strains toward various biochemicals using different strategies (Alper, Moxley, Nevoigt, Fink, & Stephanopoulos, 2006; Atsumi et al, 2010; Dunlop et al, 2011; Goodarzi et al, 2010). An alternative to this approach is to identify alternative production hosts that are naturally tolerant to higher concentrations of the chemicals of interest.…”

Synthetic RNA devices to expedite the evolution of metabolite-producing microbes

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