title: Enzyme-catalysed carbon-carbon bond formation: large-scale production of Escherichia coli transketolase.
abstract: Escherichia coli strain JM107/pQR700 possesses the vector pBGS18, a high copy number plasmid carrying kanamycin resistance, into which a 4.4 kb fragment containing the transketolase gene had been cloned. The bacterium was grown at 20 and 1000 1 scale for the production of transketolase. The specific growth rate was maintained at 0.15 h-1 until the bacterial concentration reached 20 g dry wt per litre at which point the culture was harvested. The clarified cell extract obtained after disruption of the bacteria in a high-pressure homogeniser contained about 230 U ml-1 of the enzyme, which represented about 40% of the total protein released. No further purification was done at large scale as the clarified cell extract could be used satisfactorily for biotransformations.
authors.affiliation: The Advanced Centre for Biochemical Engineering, Department of Chemical and Biochemical Engineering, University College London, UK.
authors.forename: G R
authors.initials: GR
authors.lastname: Hobbs
authors.forename: R K
authors.initials: RK
authors.lastname: Mitra
authors.forename: R P
authors.initials: RP
authors.lastname: Chauhan
authors.forename: J M
authors.initials: JM
authors.lastname: Woodley
authors.forename: M D
authors.initials: MD
authors.lastname: Lilly
mesh_terms: D001709:Biotechnology; D001711:Biotransformation; D002244:Carbon / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D005798:Genes, Bacterial; D005822:Genetic Vectors; D010957:Plasmids / Q000235:genetics; D014174:Transketolase / Q000096:biosynthesis* / Q000235:genetics / Q000302:isolation & purification
chemical_list: D002244:Carbon; D014174:Transketolase