title: Productivity of cyclohexanone oxidation of the recombinant Corynebacterium glutamicum expressing chnB of Acinetobacter calcoaceticus.
abstract: The biocatalytic efficiency of recombinant Corynebacterium glutamicum expressing the chnB gene encoding cyclohexanone monooxygenase (CHMO) of Acinetobacter calcoaceticus NCIMB 9871 was investigated. Optimization of an expression system and induction conditions enabled the recombinant biocatalyst to produce CHMO to a specific activity of ca. 0.5 U mg(-1) protein. Tight control of feeding of an energy source (i.e., glucose) and dissolved oxygen tension during fed-batch culture-based biotransformation allowed the cells to produce epsilon-caprolactone to a concentration of 16.0 g l(-1). The specific and volumetric productivity for cyclohexanone oxidation were 0.12 g g drycells(-1)h(-1) (17.5 U g(-1) of dry cells) and 2.3 g l(-1)h(-1) (330 U l(-1)), respectively. These values correspond to over 5.4- and 2.7-fold of recombinant Escherichia coli expressing the same gene under similar reaction conditions. It could be concluded that the recombinant C. glutamicum is a promising biocatalyst for Baeyer-Villiger oxidations.
authors.affiliation: Department of Food Science & Engineering, Ewha Womans University, Seoul 120-750, Republic of Korea.
authors.forename: Eun-Hee
authors.initials: EH
authors.lastname: Doo
authors.forename: Won-Heong
authors.initials: WH
authors.lastname: Lee
authors.forename: Hyo-Seel
authors.initials: HS
authors.lastname: Seo
authors.forename: Jin-Ho
authors.initials: JH
authors.lastname: Seo
authors.forename: Jin-Byung
authors.initials: JB
authors.lastname: Park
mesh_terms: D016954:Acinetobacter calcoaceticus / Q000201:enzymology* / Q000235:genetics; D055162:Biocatalysis; D002208:Caproates / Q000378:metabolism; D002452:Cell Count; D048230:Corynebacterium glutamicum / Q000235:genetics* / Q000378:metabolism; D003512:Cyclohexanones / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D007783:Lactones / Q000378:metabolism; D010084:Oxidation-Reduction; D010100:Oxygen / Q000378:metabolism; D010105:Oxygenases / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D002208:Caproates; D003512:Cyclohexanones; D007783:Lactones; D011994:Recombinant Proteins; C121056:caprolactone; C036468:cyclohexanone; D010105:Oxygenases; C019961:cyclohexanone oxygenase; D005947:Glucose; D010100:Oxygen