FIG 5.

Requirement of ptvR for transcriptional induction of the ptv operon by vancomycin. The transcriptional luc reporter derivatives TH9753 (P_ptv_luc) and TH9754 (Δptv mutant strain; P_ptv_luc) of D39, constructed in the presence (A) or absence (B) of ptvR, were cultured until the OD₅₉₅ reached ∼0.4 and subsequently exposed to various concentrations of vancomycin. Cell density and luciferase activity of the cultures are presented as the optical density (OD₅₉₅) and the relative luminescence units per OD (RLU/OD), respectively.