FIG. 8.

Effect of overexpressed ς^B on the expression of hldP::luc+. S. aureus derivatives of strain MB95 (BB255 hldp::luc+), harboring plasmid pIK64 (P_xyl::sigB) (A) or control plasmid pTX15 (P_xyl) (B), were grown in LB medium at 37°C. Growth was measured as the OD₆₀₀ (closed symbols). Growing cultures were split into equal parts at the OD₆₀₀ of 1, and overexpression of ς^B was induced in one of the parts by supplementing 0.5% xylose (diamonds), while the control part was left without addition (squares). The arrow denotes the time point of supplementation. hldp::luc+ expression (open symbols) was determined by measuring the luciferase activity of the reporter gene luc+ as described in Materials and Methods.