Fig. 3.

Variation in the mutational profile for ofloxacin-resistance after fluctuation analyses using nine genetically distinct Mycobacterium tuberculosis strains. (A) Mutations in the quinolone-resistance-determining region (QRDR) of gyrA were analyzed in 680 ofloxacin (OFX)-resistant colonies from the fluctuation analysis performed in figure 2A (nm, no identified QRDR gyrA mutations). Strains are ordered left to right based on their frequency of OFX-resistance at 4 µg/ml OFX. Numbers of colonies analyzed per strain are reported directly above each column. (B) The number of unique QRDR gyrA mutations per Mtb strain for OFX-resistance. Bar colors denote the Mtb lineage the strain belongs to (L1, pink; L2, blue; L4, red).