The insertion of the inverted repeat of an insertion sequence (IS) element from <i>Lacticaseibacillus rhamnosus</i> changes the host range and stability of pGK12, a shuttle vector for lactic acid bacteria

This study highlights the significant impact of insertion sequence (IS) elements on plasmid replication in lactobacilli. The spontaneous integration of an IS element from the <i>Laticaseibacillus rhamnosus</i> genome into plasmid pGK12 not only expands its host range in previously incompatible strains but also changes plasmid stability and copy number. This expansion of the plasmid's host range is crucial for developing versatile genetic tools across diverse lactobacilli species. Additionally, the stable plasmid variant of pGK12 with the IS element insertion offers a valuable tool for cloning and gene expression in lactobacilli. These findings enhance our understanding of plasmid-IS element interactions and may provide insight into a new method to expand the host range of existing plasmids.