FIG 3.

NB95031 demonstrates increased toxin levels at subinhibitory concentrations of metronidazole and vancomycin. Strain NB95031 was grown for 72 h in the presence of the indicated antibiotics. Remaining viable cells (log₁₀ CFU/ml, lines) and toxin A and B production (A₄₅₀, bars) were measured. FDX, fidaxomicin; VAN, vancomycin; MET, metronidazole. Data are means and SEM of duplicate antibiotic treatments.