Figure 2
Cell surface of Msmeg-PE11 is highly hydrophobic.
(a) Pellicle formation of Msmeg-pVV or Msmeg-PE11 was monitored by growing standing cultures of the strains without shaking in Middlebrook 7H9 medium in absence of Tween 80 at 37 °C for various time points. (b) Biofilm formation was quantified by crystal violet staining for which Msmeg-pVV or Msmeg-PE11 cells were washed, stained with 1% crystal violet and ethanol extract was spectrophotometrically measured at 570 nm. (c) Msmeg-pVV or Msmeg-PE11 were cultured in 7H9 medium with (upper panel) or without (lower panel) 0.05% Tween-80 at 37 °C with shaking for 24 h and 48 h. Cultures were then allowed to settle at room temperature for 30 min. (d) In another experiment, Msmeg-pVV or Msmeg-PE11 were cultured in 7H9 broth with congo red (100 μg/ml) and 0.05% Tween 80 for 24 h, 48 h and 72 h at 37 °C. Cells were next washed and re-suspended in acetone. Congo red in the supernatant was spectrophotometrically measured at 490 nm. Data are representative of mean ± SD of three different experiments.
