title: Recycling Carbon Dioxide during Xylose Fermentation by Engineered Saccharomyces cerevisiae.
abstract: Global climate change caused by the emission of anthropogenic greenhouse gases (GHGs) is a grand challenge to humanity. To alleviate the trend, the consumption of fossil fuels needs to be largely reduced and alternative energy technologies capable of controlling GHG emissions are anticipated. In this study, we introduced a synthetic reductive pentose phosphate pathway (rPPP) into a xylose-fermenting Saccharomyces cerevisiae strain SR8 to achieve simultaneous lignocellulosic bioethanol production and carbon dioxide recycling. Specifically, ribulose-1,5-bisphosphate carboxylase/oxygenase from Rhodospirillum rubrum and phosphoribulokinase from Spinacia oleracea were introduced into the SR8 strain. The resulting strain with the synthetic rPPP was able to exhibit a higher yield of ethanol and lower yields of byproducts (xylitol and glycerol) than a control strain. In addition, the reduced release of carbon dioxide by the engineered strain was observed during xylose fermentation, suggesting that the carbon dioxide generated by pyruvate decarboxylase was partially reassimilated through the synthetic rPPP. These results demonstrated that recycling of carbon dioxide from the ethanol fermentation pathway in yeast can be achieved during lignocellulosic bioethanol production through a synthetic carbon conservative metabolic pathway. This strategy has a great potential to alleviate GHG emissions during the production of second-generation ethanol.
authors.affiliation: School of Environmental Science and Engineering, Shandong University , 27 Shanda Nanlu, Jinan 250100, People's Republic of China.|Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign , 1206 West Gregory Drive, Urbana, Illinois 61801, United States.
authors.forename: Peng-Fei
authors.initials: PF
authors.lastname: Xia
authors.affiliation: Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign , 905 South Goodwin Avenue, Urbana, Illinois 61801, United States.
authors.forename: Guo-Chang
authors.initials: GC
authors.lastname: Zhang
authors.affiliation: Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign , 1206 West Gregory Drive, Urbana, Illinois 61801, United States.|Photosynthetic Research Unit, United States Department of Agriculture , Urbana Illinois 61801, United States.
authors.forename: Berkley
authors.initials: B
authors.lastname: Walker
authors.affiliation: Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign , 905 South Goodwin Avenue, Urbana, Illinois 61801, United States.
authors.forename: Seung-Oh
authors.initials: SO
authors.lastname: Seo
authors.affiliation: Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign , 1206 West Gregory Drive, Urbana, Illinois 61801, United States.|Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign , 905 South Goodwin Avenue, Urbana, Illinois 61801, United States.
authors.forename: Suryang
authors.initials: S
authors.lastname: Kwak
authors.affiliation: Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign , 1206 West Gregory Drive, Urbana, Illinois 61801, United States.
authors.forename: Jing-Jing
authors.initials: JJ
authors.lastname: Liu
authors.affiliation: Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign , 1206 West Gregory Drive, Urbana, Illinois 61801, United States.|Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign , 905 South Goodwin Avenue, Urbana, Illinois 61801, United States.
authors.forename: Heejin
authors.initials: H
authors.lastname: Kim
authors.affiliation: Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign , 1206 West Gregory Drive, Urbana, Illinois 61801, United States.|Photosynthetic Research Unit, United States Department of Agriculture , Urbana Illinois 61801, United States.|Department of Plant Biology, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801, United States.
authors.forename: Donald R
authors.initials: DR
authors.lastname: Ort
authors.affiliation: School of Environmental Science and Engineering, Shandong University , 27 Shanda Nanlu, Jinan 250100, People's Republic of China.
authors.forename: Shu-Guang
authors.initials: SG
authors.lastname: Wang
authors.affiliation: Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign , 1206 West Gregory Drive, Urbana, Illinois 61801, United States.|Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign , 905 South Goodwin Avenue, Urbana, Illinois 61801, United States.
authors.forename: Yong-Su
authors.initials: YS
authors.lastname: Jin
mesh_terms: D002245:Carbon Dioxide / Q000378:metabolism*; D057231:Climate Change; D000431:Ethanol / Q000378:metabolism; D005285:Fermentation / Q000502:physiology*; D005818:Genetic Engineering / Q000379:methods; D005947:Glucose / Q000378:metabolism; D005990:Glycerol / Q000378:metabolism; D053858:Metabolic Networks and Pathways / Q000502:physiology; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000378:metabolism; D011767:Pyruvate Decarboxylase / Q000378:metabolism; D012274:Ribulosephosphates / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism; D014993:Xylitol / Q000378:metabolism; D014994:Xylose / Q000378:metabolism*
chemical_list: D012274:Ribulosephosphates; D029701:Saccharomyces cerevisiae Proteins; D002245:Carbon Dioxide; C001933:ribulose-1,5 diphosphate; D000431:Ethanol; D014994:Xylose; D017853:Phosphotransferases (Alcohol Group Acceptor); C022390:phosphoribulokinase; D011767:Pyruvate Decarboxylase; D005947:Glucose; D005990:Glycerol; D014993:Xylitol
keywords: CO2 recycling; Saccharomyces cerevisiae; bioethanol; carbon conservation