Shotgun cloning inStreptococcus lactis

Using plasmid vector pIL204 and a recently described high-efficiency transformation protocol, we performed a direct shotgun cloning experiment in Streptococcus lactis. The cloned DNA was a 22 kilobases fragment of the S. lactis chromosome previously labelled by insertion of transposon Tn916 encoding tetracycline resistance. An interesting feature of the present shotgun cloning system is its ability to clone large-size DNA fragments.