PuC18 is a common bacterial plasmid for E. Coli. Genetic engineering allows multiple sites to be inserted into the dsDNA loop such as the gene and promoter for beta-galactosidase, lacZ. The lacZ gene contains a polylinker region that is 54 base pairs in length and contains 13 different restriction sites for restriction endonucleases involved in procedures such as DNA recombination.
<ref>tags exist, but no
<references/>tag was found