Fig. 3.

Growth of B. fragilis Δoxe strains in rich medium. ADB77 (■), ADB267 (▲), ADB267/pJST61 (●), and ADB267/pADB293 (◆) were grown anaerobically to late log-phase in BHIS with or without erythromycin. These cultures were diluted 1:1,000 into fresh medium and shaken in flasks at 200 rpm in an anaerobic chamber (A) or in a chamber containing 1% oxygen (B). Samples were diluted in PBS solution. Aliquots (10 μL) were spotted to prereduced BHIS plates (with or without erythromycin) and incubated in the anaerobic chamber. Counts (in cfu) were enumerated after 24 to 36 h incubation by using a stage microscope. Results shown are the means of three experiments ± SEM.