Protocol for in vitro mutagenesis using double-stranded DNA templates. Two oligonucleotides are used to prime DNA synthesis catalyzed by a high-fidelity thermostable polymerase on a denatured plasmid template. The two oligonucleotides both contain the desired mutation and occupy the same starting and ending positions on opposite strands of the plasmid DNA. - [Read In Vitro Mutagenesis Using Double-stranded DNA Templates: Selection of Mutants with DpnI]
Protocol exploits the discovery that Rnase A can efficiently cleave at single rC or rU bases embedded in double-stranded DNA. Entire plasmid vectors are amplified using long, high-fidelity PCR with riboprimers, which carry a single rC residue at their 3' end. Target DNA is amplified using similar primers, which also end in a rC residue. - [Read Ribocloning: DNA Cloning and Gene Construction Using PCR Primers Terminated with a Ribonucleotide]