If a gene is inserted in the pBR 322 plasmid by using the enzyme Bam H I, and the rDNA is incorporated into E.coli host. Identify the functions of the marker gene.

If a gene is inserted in pBR322 at BamHI, site, the tetRmarker is inactivated by insertion and this one helps in identifying recombinants from non-recombinants. The other marker ampRhelps in selecting transformants from non-transformants.