title: Site-specific mutagenesis method which completely excludes wild-type DNA from the transformants.
abstract: A highly efficient site-specific mutagenesis method has been devised to exclude wild-type DNA from incorporation into the transformed cells. Two complementary oligonucleotides, corresponding to a target sequence of a DNA molecule and containing an insertion mutation which created an endonuclease restriction site, were synthesized. By using the wild-type DNA molecule flanked by two restriction sites on each side of the target region as a template, the two oligonucleotide primers were extended, enriched, and isolated. The extended products, in turn, were used as templates in a polymerase chain reaction to obtain a mutagenized double-stranded DNA fragment which was conveniently cloned into plasmids by using the flanking restriction sites. Escherichia coli cells transformed by these plasmids were subject to large-scale analysis. One hundred percent of the transformants examined by colony hybridization, restriction enzyme analysis, and DNA sequencing were found to contain the mutant DNA sequence.
authors.affiliation: Department of Genetics, Interferon Sciences, Inc., New Brunswick, New Jersey 08901.
authors.forename: N
authors.initials: N
authors.lastname: Lee
authors.forename: J
authors.initials: J
authors.lastname: Liu
authors.forename: C
authors.initials: C
authors.lastname: He
authors.forename: D
authors.initials: D
authors.lastname: Testa
mesh_terms: D001483:Base Sequence; D004269:DNA, Bacterial / Q000138:chemical synthesis / Q000302:isolation & purification*; D004926:Escherichia coli / Q000737:chemistry / Q000235:genetics; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010957:Plasmids; D016133:Polymerase Chain Reaction; D014169:Transformation, Bacterial
chemical_list: D004269:DNA, Bacterial