We have extended the technique of PCR-directed recombination in Saccha
romyces cerevisiae to develop a simple method for plasmid or gene cons
truction in the absence of suitable restriction sites. The DNA to be c
loned is PCR-amplified with 30-40 bp of homology to a linearized yeast
plasmid. Co-transformation into yeast results in homologous recombina
tion ata position directed by the PCR oligonucleotides.