Fig. 8.

Disruption of the P1 promoter in the chromosome does not affect the production of Coa and Hla. (A) Nature of the P1 mutation in the chromosome. Two nucleotides in the SaeR binding site, which were previously shown to be essential for P1 function, were mutated with pKOR1. The SaeR binding sequences are boldface, while promoter sequences are underlined and indicated with a rectangle. (B) Effect of the P1 mutation on expression of Coa and Hla. Cells were grown to exponential growth phase; then, the proteins Coa, Hla, SaeS, and SaeR were detected by Western blot analysis. NM, wild-type strain; Δ(pCL-RS^P), NMΔsae(pCL-RS^P); NM-P1m, strain Newman with the chromosomal P1 mutation; USA, USA300-P23; Δ(pCL-RS^L), NMΔsae(pCL-RS^L); USA-P1m, USA300-P23 with the chromosomal P1 mutation. (C) Effect of the P1 mutation on Coa expression upon induction by human neutrophil peptide 1 (HNP-1). Cells were grown to exponential growth phase and then induced with HNP-1 for 2 h. Coa in culture supernatant was analyzed by Western blot analysis.