Figure 1

Schematic presentations of mutagenesis PCR amplification processes. A) Using the primers designed as recommended in the QuickChange™ protocol. PCR extension fails when primers annealed to newly synthesised "nicked" DNA. B) Using the new primer design to generate single-site mutation, deletion or insertion. C) Using the new primer design to generate double mutations, deletions or insertions. The gray cycles represent the parental plasmid DNA, the cycles of dash lines represent the DNA amplified using the parental DNA as templates while the cycles of gapped dash line are the DNA amplified using the newly-synthesized DNA as templates. Arrows indicate the numbered primers; Triangles indicate the location of the mutations/deletions/insertions; Short bars indicate the "nicks" in the newly-synthesized DNA molecules.