Engineering Yeast Transcription Machinery for Improved Ethanol Tolerance and Production

Department of Chemical Engineering, Massachusetts Institute of Technology, Room 56-469, Cambridge, MA 02139, USA.
Science (Impact Factor: 31.48). 01/2007; 314(5805):1565-8. DOI: 10.1126/science.1131969
Source: PubMed

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 (Phe177Ser) and, similarly, Tyr195His, and Lys218Arg]. Thus, gTME can provide a route to complex phenotypes that are not readily accessible by traditional methods.

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