title: Bacteriophage lambda-E. coli K12 vector-host system for gene cloning and expression under lactose promoter control: I. DNA fragment insertion at the lacZ EcoRI restriction site.
abstract: Bacteriophage lambda vectors, derived from lambda plac5 were constructed. Their genomes have only one EcoRI restriction site, located near the end of the beta-galactosidase gene. Recombinants, constructed in vitro, having a DNA fragment inserted in the EcoRI site, are lac- and can be easily recognized. Expression of such foreign genes is then under the control of the lac promoter. Mutations Qam73 and Sam7 greatly increase the amount of beta-galactosidase synthesized by the vector bacteriophage. The lambda ZEQS vector has been certified B2 (EK2) by the French control commission "Recombinaisons génétiques in vitro".
mesh_terms: D003090:Coliphages / Q000235:genetics*; D004274:DNA, Recombinant; D004279:DNA, Viral / Q000235:genetics*; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000235:genetics; D005696:Galactosidases / Q000235:genetics*; D005814:Genes, Viral; D007763:Lac Operon; D001616:beta-Galactosidase / Q000235:genetics*
chemical_list: D004274:DNA, Recombinant; D004279:DNA, Viral; D005696:Galactosidases; D001616:beta-Galactosidase