title: Site-specific insertion of gene cassettes into integrons.
abstract: Site-specific insertion of gene cassettes into the insert region of integrons has been demonstrated. Insertion was only observed if the integron DNA integrase was expressed in the recipient cell and if the cassette DNA was ligated prior to transformation. The essential ligation products were resistant to treatment with exonuclease III, indicating that they were closed circular molecules. Insertion of cassettes into integron fragments containing either no insert (one recombination site), or one gene cassette (two recombination sites), was demonstrated. In the latter case, insertion occurred predominantly at the core site located 5' to the resident cassette, which corresponds to the only site available when no insert is present in the recipient. When DNA molecules including two gene cassettes were used, insertion of only one of the gene cassettes was generally observed, suggesting that resolution of the circular molecule to generate two independent circular cassettes occurred more rapidly than insertion into the recipient integron.
authors.affiliation: CSIRO Division of Biomolecular Engineering, Sydney Laboratory, North Ryde, New South Wales Australia.
authors.forename: C M
authors.initials: CM
authors.lastname: Collis
authors.forename: G
authors.initials: G
authors.lastname: Grammaticopoulos
authors.forename: J
authors.initials: J
authors.lastname: Briton
authors.forename: H W
authors.initials: HW
authors.lastname: Stokes
authors.forename: R M
authors.initials: RM
authors.lastname: Hall
mesh_terms: D001483:Base Sequence; D004254:DNA Nucleotidyltransferases / Q000235:genetics*; D004251:DNA Transposable Elements / Q000235:genetics*; D004269:DNA, Bacterial / Q000235:genetics; D004270:DNA, Circular / Q000235:genetics; D004274:DNA, Recombinant / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D019426:Integrases; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D016297:Mutagenesis, Site-Directed; D011995:Recombination, Genetic
chemical_list: D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D004270:DNA, Circular; D004274:DNA, Recombinant; D004254:DNA Nucleotidyltransferases; D019426:Integrases