Fig 7. SufT is essential for in vitro growth and regulates survival under redox stress and inside macrophages.

(A) A gradual decrease in the growth of the SufT-KD strain with increasing concentration of ATc (0–200 ng/mL) in standard liquid 7H9 medium. (B) Image of the serially diluted (N = undiluted) culture spotting of control as well as SufT-KD on 7H11 plates with and without ATc (200 ng/mL). Log phase culture of control +ATc, SufT-KD+ATc and–ATc were diluted to 0.15 OD (~2x 10⁷ cells/mL) and treated with (C) H₂O₂ (0 mM, 5 mM and 10 mM) or (D) DETA NO (0 mM, 0.5 mM and 1 mM) for 12 h. Ex vivo survival of control +ATc, SufT-KD +ATc, and–ATc was performed in (E) THP-1 and (F) RAW264.7 cell line. Infection was performed at MOI: 2 for 4 h (0 h). CFU was measured at 0, 24, 48 and 72 h of infection. Experiments were performed in triplicate with two independent experiments. Two-way analysis of variance (ANOVA) as applicable with multiple comparisons test was employed to determine statistical significance. **p ≤ 0.01 and ***p ≤ 0.001.