Improved production of ethanol by deleting FPS1 and over-expressing GLT1 in Saccharomyces cerevisiae.
To improve ethanol production in Saccharomyces cerevisiae, two yeast strains were constructed. In the mutant KAM-3, the FPS1 gene, which encodes a channel protein responsible for glycerol export, was deleted. The mutant KAM-11 had the GLT1 gene (encoding glutamate synthase) placed under the PGK1 promoter while having the FPS1 deletion. Growth rate and biomass concentration remained virtually unchanged with the mutant KAM-11, compared to that of the parent. Over-expression of GLT1 by the PGK1 promoter along with FPS1 deletion resulted in a 14% higher ethanol production and a 30% lower glycerol formation compared to the parental strain under anaerobic fermentation conditions. Furthermore, acetate and pyruvic acid formation was also reduced in order for cells to maintain redox balance.
Kong
Qing-Xue
QX
School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.
Gu
Ji-Guang
JG
Cao
Li-Min
LM
Zhang
Ai-Li
AL
Chen
Xun
X
Zhao
Xue-Ming
XM
D004526:Efficiency; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation / Q000235:genetics; D017353:Gene Deletion; D015966:Gene Expression Regulation, Fungal; D005970:Glutamate Synthase / Q000235:genetics*; D007218:Industrial Microbiology / Q000379:methods; D008565:Membrane Proteins / Q000235:genetics*; D008954:Models, Biological; D030781:Organisms, Genetically Modified; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics*; D015854:Up-Regulation
C093263:FPS1 protein, S cerevisiae; D008565:Membrane Proteins; D029701:Saccharomyces cerevisiae Proteins; D000431:Ethanol; D005970:Glutamate Synthase