FIG 6.

Detection of M. tuberculosis subsp. bovis bacillus Calmette-Guérin (BCG) in sputum using reporter enzyme fluorescence (REF) assays with the fluorogenic substrate CDG-3. CDG-3 at 10 μM (A), 5 μM (B), and 0.01 μM (C) was coincubated in sputum with transport stabilization solution (TSS) that contained 100 CFU of BCG. Every 20 min for 180 min at room temperature (25°C), the change in fluorescence (ΔF) was measured and calculated as the fluorescent signal (excitation, 490 nm; emission, 515 nm) at each time point minus the signal immediately after adding the substrate. P values shown on each line are derived from ANOVA comparison of data for sputum with 100 CFU BCG and sputum alone.