Insertion sequence IS2 near the gene for prophage λ excision

Abstract
In this study we characterize a variant of the λcI857S7 prophage, designated λbi2cI857S7, which carries a DNA insertion. The insertion sequence is IS2, and it resides in the antipolar orientation II just upstream from the gene for prophage excision (xis) at 61.6%λ. This bi2 insertion mutant could prove valuable for studies on possible recombination functions of IS2 DNA and of its effect on the λ integration and excision functions.