Site-directed mutagenesis with Escherichia coli DNA polymerase III holoenzyme

Escherichia coli DNA polymerase III holoenzyme was used to synthesize double-stranded DNA from M 13 single-stranded DNA hybridized to a phosphorylated synthetic oligodeoxynucleotide containing a nucleotide substitution. The resulting DNA was transfected into E. coli JM101 without further treatment. Sequence analysis of randomly chosen phage clones revealed that the efficiency of mutagenesis was nearly 50%, which is the theoretical maximum. Treatment with DNA ligase after DNA synthesis was not necessary to obtain high efficiency of mutagenesis. Thus, use of DNA polymerase III holoenzyme provides a simple and efficient procedure for site-directed mutagenesis.