title: Efficient production of ethanol from crude glycerol by a Klebsiella pneumoniae mutant strain.
abstract: A mutant strain of Klebsiella pneumoniae, termed GEM167, was obtained by γ irradiation, in which glycerol metabolism was dramatically affected on exposure to γ rays. Levels of metabolites of the glycerol reductive pathway, 1,3-propanediol (1,3-PD) and 3-hydroxypropionic acid (3-HP), were decreased in the GEM167 strain compared to a control strain, whereas the levels of metabolites derived from the oxidative pathway, 2,3-butanediol (2,3-BD), ethanol, lactate, and succinate, were increased. Notably, ethanol production from glycerol was greatly enhanced upon fermentation by the mutant strain, to a maximum production level of 21.5 g/l, with a productivity of 0.93 g/l/h. Ethanol production level was further improved to 25.0 g/l upon overexpression of Zymomonas mobilis pdc and adhII genes encoding pyruvate decarboxylase (Pdc) and aldehyde dehydrogenase (Adh), respectively in the mutant strain GEM167.
authors.affiliation: Microbe-based Fusion Technology Research Center, Jeonbuk Branch Institute, KRIBB, Jeongeup, Jeonbuk 580-185, South Korea.
authors.forename: Baek-Rock
authors.initials: BR
authors.lastname: Oh
authors.forename: Jeong-Woo
authors.initials: JW
authors.lastname: Seo
authors.forename: Sun-Yeon
authors.initials: SY
authors.lastname: Heo
authors.forename: Won-Kyung
authors.initials: WK
authors.lastname: Hong
authors.forename: Lian Hua
authors.initials: LH
authors.lastname: Luo
authors.forename: Min-ho
authors.initials: MH
authors.lastname: Joe
authors.forename: Don-Hee
authors.initials: DH
authors.lastname: Park
authors.forename: Chul Ho
authors.initials: CH
authors.lastname: Kim
mesh_terms: D000444:Aldehyde Dehydrogenase / Q000737:chemistry; D001709:Biotechnology / Q000379:methods*; D002072:Butylene Glycols / Q000737:chemistry; D000431:Ethanol / Q000737:chemistry*; D005285:Fermentation; D005720:Gamma Rays; D005990:Glycerol / Q000737:chemistry*; D007711:Klebsiella pneumoniae / Q000235:genetics*; D007773:Lactates / Q000737:chemistry; D019344:Lactic Acid / Q000031:analogs & derivatives / Q000737:chemistry; D009154:Mutation; D011409:Propylene Glycols / Q000737:chemistry; D011767:Pyruvate Decarboxylase / Q000737:chemistry; D019802:Succinic Acid / Q000737:chemistry; D017355:Zymomonas / Q000201:enzymology
chemical_list: D002072:Butylene Glycols; D007773:Lactates; D011409:Propylene Glycols; D019344:Lactic Acid; D000431:Ethanol; C026978:2,3-butylene glycol; C041787:1,3-propanediol; D019802:Succinic Acid; C031601:hydracrylic acid; D000444:Aldehyde Dehydrogenase; D011767:Pyruvate Decarboxylase; D005990:Glycerol