Single-step assembly of a gene and entire plasmid from large numbers of oligodeoxyribonucleotides

Gene. 1995 Oct 16;164(1):49-53. doi: 10.1016/0378-1119(95)00511-4.

Abstract

Here, we describe assembly PCR as a method for the synthesis of long DNA sequences from large numbers of oligodeoxyribonucleotides (oligos). The method, which is derived from DNA shuffling [Stemmer, Nature 370 (1994a) 389-391], does not rely on DNA ligase but instead relies on DNA polymerase to build increasingly longer DNA fragments during the assembly process. A 1.1-kb fragment containing the TEM-1 beta-lactamase-encoding gene (bla) was assembled in a single reaction from a total of 56 oligos, each 40 nucleotides (nt) in length. The synthetic gene was PCR amplified and cloned in a vector containing the tetracycline-resistance gene (TcR) as the sole selectable marker. Without relying on ampicillin (Ap) selection, 76% of the TcR colonies were ApR, making this approach a general method for the rapid and cost-effective synthesis of any gene. We tested the range of assembly PCR by synthesizing, in a single reaction vessel containing 134 oligos, a high-molecular-mass multimeric form of a 2.7-kb plasmid containing the bla gene, the alpha-fragment of the lacZ gene and the pUC origin of replication. Digestion with a unique restriction enzyme, followed by ligation and transformation in Escherichia coli, yielded the correct plasmid. Assembly PCR is well suited for several in vitro mutagenesis strategies.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • DNA-Directed DNA Polymerase / metabolism
  • Genes, Synthetic*
  • Oligodeoxyribonucleotides / metabolism*
  • Plasmids / biosynthesis*
  • Polymerase Chain Reaction / methods*
  • beta-Lactamases / genetics*

Substances

  • Oligodeoxyribonucleotides
  • DNA-Directed DNA Polymerase
  • beta-Lactamases
  • beta-lactamase TEM-1