induction effect on ebpA expression level. Samples were collected every hour from 3 to 8 hr, then at 10 and 24 hr after starting the culture in TSBG. The left axis represents the β-gal units (OD420 nm/protein concentration in mg/ml). The right axis indicates the OD600 nm readings. All sets of cultures presented were analyzed concurrently. Each figure is a representative of at least three experiments. A. Growth curves of OG1RF are shown in gray (in air) and in orange (in the presence of 5% CO2/0.1 M NaHCO3). OG1RF containing P
::lacZ (triangle) or P
::lacZ (square) was grown in air (closed black symbol) or in the presence of 5% CO2/0.1 M NaHCO3 (open orange symbol). B. The ΔebpR mutant containing P
::lacZ is represented by closed green diamond when grown in air and with open brown diamond when grown in the presence of 5% CO2/0.1 M NaHCO3.