Table 1 Description of M. smegmatis strains used in this study and corresponding MICs determined for EtBr and efflux inhibitors

mc ² 155

Wild-type [34]

6.25

25

12.5

200

SMR5

mc²155 derivative; resistant to streptomycin due to a mutation in ribosomal protein S12 (rpsL) [29]

6.25

25

12.5

400

MN01

SMR5 ΔmspA [5]

6.25

25

25

400

ML10

SMR5 ΔmspA ΔmspC [28]

12.5

25

25

250

XZL1675

mc²155 ΔlfrA [15]

0.4

25

6.25

125

XZL1720

mc²155 ΔlfrR [15]

6.25

25

12.5

200