Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6494755 | Metabolic Engineering | 2013 | 54 Pages |
Abstract
Engineering of metabolic pathways by genetic modification has been restricted largely to enzyme-encoding structural genes. The product yield of such pathways is a quantitative genetic trait. Out of 52 Saccharomyces cerevisiae strains phenotyped in small-scale fermentations, we identified strain CBS6412 as having unusually low glycerol production and higher ethanol yield as compared to an industrial reference strain. We mapped the QTLs underlying this quantitative trait with pooled-segregant whole-genome sequencing using 20 superior segregants selected from a total of 257. Plots of SNP variant frequency against SNP chromosomal position revealed one major and one minor locus. Downscaling of the major locus and reciprocal hemizygosity analysis identified an allele of SSK1, ssk1E330Nâ¦K356N, expressing a truncated and partially mistranslated protein, as causative gene. The diploid CBS6412 parent was homozygous for ssk1E330Nâ¦K356N. This allele affected growth and volumetric productivity less than the gene deletion. Introduction of the ssk1E330Nâ¦K356N allele in the industrial reference strain resulted in stronger reduction of the glycerol/ethanol ratio compared to SSK1 deletion and also compromised volumetric productivity and osmotolerance less. Our results show that polygenic analysis of yeast biodiversity can provide superior novel gene tools for metabolic engineering.
Keywords
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Bioengineering
Authors
Georg Hubmann, Maria R. Foulquié-Moreno, Elke Nevoigt, Jorge Duitama, Nicolas Meurens, Thiago M. Pais, Lotte Mathé, Sofie Saerens, Huyen Thi Thanh Nguyen, Steve Swinnen, Kevin J. Verstrepen, Luigi Concilio, Jean-Claude de Troostembergh,