title: Enhanced production of 2,3-butanediol in pyruvate decarboxylase-deficient Saccharomyces cerevisiae through optimizing ratio of glucose/galactose.
abstract: Galactose and glucose are two of the most abundant monomeric sugars in hydrolysates of marine biomasses. While Saccharomyces cerevisiae can ferment galactose, its uptake is tightly controlled in the presence of glucose by catabolite repression. It is desirable to construct engineered strains capable of simultaneous utilization of glucose and galactose for producing biofuels and chemicals from marine biomass. The MTH1 gene coding for transcription factor in glucose signaling was mutated in a pyruvate decarboxylase (Pdc)-deficient S. cerevisiae expressing heterologous 2,3-butanediol (2,3-BD) biosynthetic genes. The engineered S. cerevisiae strain consumed glucose and galactose simultaneously and produced 2,3-BD as a major product. Total sugar consumption rates increased with a low ratio of glucose/galactose, though, occurrence of the glucose depletion in a fed-batch fermentation decreased 2,3-BD production substantially. Through optimizing the profiles of sugar concentrations in a fed-batch cultivation with the engineered strain, 99.1 ± 1.7 g/L 2,3-BD was produced in 143 hours with a yield of 0.353 ± 0.022 g 2,3-BD/g sugars. This result suggests that simultaneous and efficient utilization of glucose and galactose by the engineered yeast might be applicable to the economical production of not only 2,3-BD, but also other biofuels and chemicals from marine biomass.
authors.affiliation: Department of Agricultural Biotechnology and Center for Food and Bioconvergence, Seoul National University, Seoul, Republic of Korea.
authors.forename: Eun-Ji
authors.initials: EJ
authors.lastname: Choi
authors.affiliation: Department of Agricultural Biotechnology and Center for Food and Bioconvergence, Seoul National University, Seoul, Republic of Korea.
authors.forename: Jin-Woo
authors.initials: JW
authors.lastname: Kim
authors.affiliation: Department of Agricultural Biotechnology and Center for Food and Bioconvergence, Seoul National University, Seoul, Republic of Korea.
authors.forename: Soo-Jung
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: Department of Food Science and Human Nutrition, and Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.
authors.forename: Seung-Oh
authors.initials: SO
authors.lastname: Seo
authors.affiliation: Department of Food Science and Human Nutrition, and Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.
authors.forename: Stephan
authors.initials: S
authors.lastname: Lane
authors.affiliation: Department of Advanced Fermentation Fusion Science and Technology, Kookmin University, Seoul, Republic of Korea.
authors.forename: Yong-Cheol
authors.initials: YC
authors.lastname: Park
authors.affiliation: Department of Food Science and Human Nutrition, and Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.
authors.forename: Yong-Su
authors.initials: YS
authors.lastname: Jin
authors.affiliation: Department of Agricultural Biotechnology and Center for Food and Bioconvergence, Seoul National University, Seoul, Republic of Korea.
authors.forename: Jin-Ho
authors.initials: JH
authors.lastname: Seo
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics* / Q000378:metabolism; D056804:Biofuels; D002072:Butylene Glycols / Q000138:chemical synthesis / Q000378:metabolism*; D005285:Fermentation; D005690:Galactose / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D060847:Metabolic Engineering; D009154:Mutation; D011767:Pyruvate Decarboxylase / Q000172:deficiency / Q000235:genetics* / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D056804:Biofuels; D002072:Butylene Glycols; C118806:MTH1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; C026978:2,3-butylene glycol; D011767:Pyruvate Decarboxylase; D005947:Glucose; D005690:Galactose
keywords: 2,3-Butanediol; Catabolite repression; Galactose; Pyruvate decarboxylase; Saccharomyces cerevisiae