title: Recombinant gene expression in Escherichia coli cultivation using lactose as inducer.
abstract: The use of lactose as inducer of foreign gene expression under control of the lac UV5 promoter was investigated in recombinant Escherichia coli. Chicken muscle troponin C (TnC) gene was transcripted by T7 RNA polymerase and expressed in bioreactor cultivations after a feed-forward controlled fed-batch growth phase. Cell concentrations of 22 g l-1 dry cell weight (DCW)--before induction started--were used to achieve a TnC content of 19.5% of total cell protein through an induction strategy that combined the addition of a specific lactose amount of 4.7 g g-1 DCW divided into three pulses and the addition of yeast extract (1 g l-1) together with the second and the third lactose pulses. The results presented suggest that the residual lactose concentration plays an important role on the production of the heterologous protein.
authors.affiliation: Departamento de Engenharia Química, Escola Politécnica da Universidade de Sao Paulo, Brazil.
authors.forename: A K
authors.initials: AK
authors.lastname: Gombert
authors.forename: B V
authors.initials: BV
authors.lastname: Kilikian
mesh_terms: D000818:Animals; D002645:Chickens; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics* / Q000254:growth & development; D005285:Fermentation; D005690:Galactose / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects*; D007785:Lactose / Q000494:pharmacology*; D009132:Muscles / Q000737:chemistry; D011401:Promoter Regions, Genetic; D011994:Recombinant Proteins; D014336:Troponin / Q000235:genetics; D020107:Troponin T; D014764:Viral Proteins
chemical_list: D011994:Recombinant Proteins; D014336:Troponin; D020107:Troponin T; D014764:Viral Proteins; C062210:bacteriophage T7 RNA polymerase; D012321:DNA-Directed RNA Polymerases; D007785:Lactose; D005690:Galactose