title: Lactic acid production from cellobiose and xylose by engineered Saccharomyces cerevisiae.
abstract: Efficient and rapid production of value-added chemicals from lignocellulosic biomass is an important step toward a sustainable society. Lactic acid, used for synthesizing the bioplastic polylactide, has been produced by microbial fermentation using primarily glucose. Lignocellulosic hydrolysates contain high concentrations of cellobiose and xylose. Here, we constructed a recombinant Saccharomyces cerevisiae strain capable of fermenting cellobiose and xylose into lactic acid. Specifically, genes (cdt-1, gh1-1, XYL1, XYL2, XYL3, and ldhA) coding for cellobiose transporter, β-glucosidase, xylose reductase, xylitol dehydrogenase, xylulokinase, and lactate dehydrogenase were integrated into the S. cerevisiae chromosomes. The resulting strain produced lactic acid from cellobiose or xylose with high yields. When fermenting a cellulosic sugar mixture containing 10 g/L glucose, 40 g/L xylose, and 80 g/L cellobiose, the engineered strain produced 83 g/L of lactic acid with a yield of 0.66 g lactic acid/g sugar (66% theoretical maximum). This study demonstrates initial steps toward the feasibility of sustainable production of lactic acid from lignocellulosic sugars by engineered yeast.
authors.affiliation: Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, Illinois.|Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana 61801, Illinois.
authors.forename: Timothy L
authors.initials: TL
authors.lastname: Turner
authors.affiliation: Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, Illinois.|Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana 61801, Illinois.
authors.forename: Guo-Chang
authors.initials: GC
authors.lastname: Zhang
authors.affiliation: Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, Illinois.|Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana 61801, Illinois.
authors.forename: Eun Joong
authors.initials: EJ
authors.lastname: Oh
authors.affiliation: Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana 61801, Illinois.
authors.forename: Vijay
authors.initials: V
authors.lastname: Subramaniam
authors.affiliation: Department of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois.
authors.forename: Andrew
authors.initials: A
authors.lastname: Adiputra
authors.affiliation: Department of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois.
authors.forename: Vimal
authors.initials: V
authors.lastname: Subramaniam
authors.affiliation: United States Department of Agriculture (USDA), Agricultural Research Service (ARS), National Center for Agricultural Utilization Research (NCAUR), Renewable Product Technology (RPT) Research Unit, Peoria, Illinois.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Skory
authors.affiliation: IT Convergence Materials R&D Group, Research Institute of Sustainable Manufacturing System, Korea Institute of Industrial Technology (KITECH), Cheonan, Korea.
authors.forename: Ji Yeon
authors.initials: JY
authors.lastname: Jang
authors.affiliation: IT Convergence Materials R&D Group, Research Institute of Sustainable Manufacturing System, Korea Institute of Industrial Technology (KITECH), Cheonan, Korea.
authors.forename: Byung Jo
authors.initials: BJ
authors.lastname: Yu
authors.affiliation: IT Convergence Materials R&D Group, Research Institute of Sustainable Manufacturing System, Korea Institute of Industrial Technology (KITECH), Cheonan, Korea.
authors.forename: In
authors.initials: I
authors.lastname: Park
authors.affiliation: Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, Illinois. ysjin@illinois.edu.|Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana 61801, Illinois. ysjin@illinois.edu.
authors.forename: Yong-Su
authors.initials: YS
authors.lastname: Jin
mesh_terms: D019149:Bioreactors / Q000382:microbiology; D002475:Cellobiose / Q000235:genetics / Q000378:metabolism*; D005285:Fermentation; D007770:L-Lactate Dehydrogenase / Q000235:genetics / Q000378:metabolism; D019344:Lactic Acid / Q000378:metabolism*; D060847:Metabolic Engineering / Q000379:methods*; D010957:Plasmids / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics* / Q000378:metabolism; D014994:Xylose / Q000235:genetics / Q000378:metabolism*
chemical_list: D002475:Cellobiose; D019344:Lactic Acid; D014994:Xylose; D007770:L-Lactate Dehydrogenase
keywords: Saccharomyces cerevisiae; cellobiose; lactate dehydrogenase; lactic acid; metabolic engineering