title: [Construction of an ethanologenic Escherichia coli strain expressing beta-glucosidase].
abstract: Constructing ethanologenic strains with cellulose activity is important to achieve consolidated bioprocessing of lignocellulose for ethanol production. In this study, we integrated the pyruvate decarboxylase gene pdc and alcohol dehydrogenase gene adhB from Zymomonas mobilis ZM4 into Escherichia coli JM109 by Red recombination method to generatea recombinant strain E. coli P81 that could produce ethanol from glucose. Abeta-glucosidase gene bglB from Bacillus polymyxa 1.794 was cloned into the recombinant E. coli P81 and beta-glucosidase was expressed to give a new recombinant strain E. coli P81 (pUC19-bglB) with dual functions of cellobiose degradation and ethanol production. The extracellular beta-glucosidaseactivity was 84.78 mU/mL broth and the extracellular cellobiase activity of E. coli P81 (pUC19-bglB) was 32.32 mU/mL broth. E. coli P81 (pUC19-bglB) fermented cellobiose to ethanol with a yield of 55.8% of the theoretical value, and when glucose and cellobiose were co-fermented, the ethanol yield reached 46.5% of thetheoretical value. The construction of consolidated bioprocessing strain opens the possibility to convert cellobiose to ethanol in a single bioprocess.
authors.affiliation: State Key Laboratory of Bioreactor Engineering, School of Bioengineering, East China University of Science and Technology, Shanghai 200237, China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Bioreactor Engineering, School of Bioengineering, East China University of Science and Technology, Shanghai 200237, China.
authors.forename: Zichen
authors.initials: Z
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Bioreactor Engineering, School of Bioengineering, East China University of Science and Technology, Shanghai 200237, China.
authors.forename: Qiuqiang
authors.initials: Q
authors.lastname: Gao
authors.affiliation: State Key Laboratory of Bioreactor Engineering, School of Bioengineering, East China University of Science and Technology, Shanghai 200237, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Bao
mesh_terms: D058947:Bacterial Secretion Systems; D002482:Cellulose / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics; D001617:beta-Glucosidase / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D058947:Bacterial Secretion Systems; D011994:Recombinant Proteins; D000431:Ethanol; D002482:Cellulose; D001617:beta-Glucosidase