(A) The click-oligonucleotides used for site directed mutagenesis contained a silent C to A mutation (shown in blue), that introduces a BamHI restriction site not present in the native mCherry gene. The click-linked bases are shown in red. (B) Assembly of the click-linked pRSET-mCherry plasmid by site directed mutagenesis, introducing a BamHI watermark. (C) Gel electrophoresis (0.8% agarose gel) of SDM products (expected size 3577 bp); Lane 1, 2-log DNA ladder (New England Biolabs); lane 2, pRSET-mCherry SDM with normal primers; lane 3, pRSET-mCherry SDM with normal primers followed by DpnI digestion; lane 4, pRSET-mCherry SDM using click primers; lane 5, pRSET-mCherry SDM using click primers followed by DpnI digestion; lane 6, negative control (pRSET-mCherry SDM using water instead of primers); lane 7, negative control followed by DpnI digestion; lane 8, pRSET-mCherry template plasmid.