title: A novel Escherichia coli expression-export vector containing alkaline phosphatase as an insertional inactivation screening system.
abstract: An Escherichia coli expression-export vector was constructed (pCGV1, 6.3 kb) containing the alkaline phosphatase structural gene (phoA) located downstream from the phage lambda pR and pL promoters positioned in tandem and the cIts857 gene encoding lambda thermosensitive repressor. The phoA gene is fused to DNA encoding a hybrid signal sequence that contains the N-terminal portion of the beta-lactamase (Bla) signal sequence and the C-terminal region of the PhoA signal sequence. Within the DNA encoding hybrid signal sequence, a unique NheI restriction site is present where polymerase chain reaction (PCR)-amplified genes may be cloned. The 5' PCR primers reconstitute the C-terminal portion of either the PhoA or Bla signal sequences to restore an intact signal peptide. Recombinant phoA- clones are selected on indicator plates containing 5-bromo-4-chloro-3-indolyl phosphate.
authors.affiliation: Institute of Microbiology, University of Genova, Italy.
authors.forename: C A
authors.initials: CA
authors.lastname: Guzmán
authors.forename: G
authors.initials: G
authors.lastname: Piatti
authors.forename: M J
authors.initials: MJ
authors.lastname: Walker
authors.forename: M C
authors.initials: MC
authors.lastname: Guardati
authors.forename: C
authors.initials: C
authors.lastname: Pruzzo
mesh_terms: D000469:Alkaline Phosphatase / Q000235:genetics; D000595:Amino Acid Sequence; D001483:Base Sequence; D004926:Escherichia coli / Q000235:genetics*; D015964:Gene Expression Regulation, Bacterial; D005822:Genetic Vectors; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D021382:Protein Sorting Signals / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000378:metabolism*
chemical_list: D021382:Protein Sorting Signals; D011993:Recombinant Fusion Proteins; D000469:Alkaline Phosphatase