Fig 5.

Tetracycline and acriflavine accumulation by intact cells of M. bovis Tap-derivative strains. (A) [³H]tetracycline uptake by wild-type (squares) and KOTap mutant (circles) cells. (B) Acriflavine uptake by SUM36 (squares) and the tap_TB-overexpressing PAZ11 (triangles) cells. [³H]tetracycline and acriflavine were added to the cells at time zero. Acriflavine fluorescence emission is quenched upon binding to the DNA; thus, in contrast to [³H]tetracycline, a lower value reading indicates intracellular accumulation. The results are the average of three experiments, and error bars indicate standard deviations.