Figure 2

SSG mutagenesis at four sites. The diagrams on the left represent the PCR fragment used in the second transformation (thick horizontal bar) and the targeted site on the chromosome (thin horizontal line). The triangle below each chromosome represents the site that URA3 is inserted in the first transformation. The numbers above each PCR fragment are the base pairs between the URA3 insertion site and the ends of the fragment The first data column shows the number of ura3Δ transformants, the second column shows the percentage of ura3Δ transformants that contained the mutation. In all cases, the mutations were 10–20 bp from the end of the fragment.