Restriction digests of the clone give the following sizes (kb): KpnI--6.5; KpnI/SstI--4.3, 2.2; ClaI--6.5. The two step selection process requires a ura3 transformation host (this host can be created using pJL164 (ATCC 87471)). After transformation with the SalI linearized vector, URA3 integrants are selected on ura- plates. The designer deletion strain is then recovered by selection on 5-FOA plates (loss of URA3 and LEU2 markers by a homologous recombination event). This deleter vector is used to create designer yeast strains with a non-revertable leu2 auxotrophic marker deletion. |