Fig 3.
Various modifications to the pyrFE locus in S. aureus. The broken horizontal line indicates the chromosomal region of strains SA564RD and RN4220 that was deleted to generate strains PR01 and PR02, respectively. FE652 is the region of the pyrFE locus that allows pRLBER9 to recombine into the chromosome and disrupt pyrE expression. Strains PR03 and PR04 were generated by substituting the pyrFE genes with the pT181ts-ORI cassette from Fig. 2 in strains RN4220 and SA564RD, respectively. The ORI181 region (ORI) is indicated.