title: Overexpressing GLT1 in gpd1Delta mutant to improve the production of ethanol of Saccharomyces cerevisiae.
abstract: To improve ethanol production in Saccharomyces cerevisiae, two yeast strains were constructed. In the mutant, KAM-4, the GPD1 gene, which encodes a glycerol 3-phosphate dehydrogenase of S. cerevisiae to synthesize glycerol, was deleted. The mutant KAM-12 had the GLT1 gene (encodes glutamate synthase) placed under the PGK1 promoter while harboring the GPD1 deletion. Notably, overexpression of GLT1 by the PGK1 promoter along with GPD1 deletion resulted in a 10.8% higher ethanol production and a 25.0% lower glycerol formation compared to the wild type in anaerobic fermentations. The growth rate of KAM-4 was slightly lower than that of the wild type under the exponential phase whereas KAM-12 and the wild type were indistinguishable in the biomass concentration at the end of growth period. Meanwhile, dramatic reduction of formation of acetate and pyruvic acid was observed in all the mutants compared to the wild type.
authors.affiliation: School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, People's Republic of China.
authors.forename: Qing-Xue
authors.initials: QX
authors.lastname: Kong
authors.forename: Li-Min
authors.initials: LM
authors.lastname: Cao
authors.forename: Ai-Li
authors.initials: AL
authors.lastname: Zhang
authors.forename: Xun
authors.initials: X
authors.lastname: Chen
mesh_terms: D018533:Biomass; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D017353:Gene Deletion; D015971:Gene Expression Regulation, Enzymologic; D015966:Gene Expression Regulation, Fungal; D005970:Glutamate Synthase / Q000235:genetics* / Q000378:metabolism; D005990:Glycerol / Q000378:metabolism; D005993:Glycerolphosphate Dehydrogenase / Q000235:genetics* / Q000378:metabolism; D007218:Industrial Microbiology / Q000379:methods; D009154:Mutation; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism
chemical_list: D000431:Ethanol; D005993:Glycerolphosphate Dehydrogenase; D005970:Glutamate Synthase; D005990:Glycerol