Site-directed insertion and deletion mutagenesis with cloned fragments in Escherichia coli

A mutation of a cloned gene that has been made by introducing a transposon or some other selectable genetic determinant can be crossed into the gene's original replicon by linearizing the cloned DNA and transforming a recB recC sbcB mutant. A number of applications of this method are described with genes of either chromosomal or plasmid origin.