FIG. 2.

Physical map of the sigB operon of S. epidermidis (accession no. AF274004) and construction of deletion mutants. Arrows depict open reading frames and indicate their orientations and sizes. All deleted genes were replaced with the erythromycin resistance gene (erm) as indicated. The erm gene and chromosomal regions flanking the respective deletions were amplified by PCR and cloned into plasmid pBT2, yielding the integration vectors pSJrsbU (A), pSJrsbV (B), pSJrsbW (C), pSJsigB (D), pSJrsbUVW (E), and pSJrsbUVWsigB (F). The crosses indicate the sites of homologous recombination.