Fig 2.

Growth characteristics of M. smegmatis Δlgt. (A) M. smegmatis wild type, M. smegmatis Δlgt, and M. smegmatis Δlgt-lgt_Mtb were grown in rich medium (a) or in nutrient-poor medium (b). (B) Inactivation of lgt affects cell and colony morphology. (a) Microcolonies of M. smegmatis grown on 7H10 agar supplemented with OADC for 3 days (total magnification, ×10); (b) auramine-stained M. smegmatis grown in 7H9-Tween (total magnification × 2000); (c) Ziehl-Neelsen-stained M. smegmatis grown in 7H9-Tween (total magnification, ×1,000); (d) electron microscopic photographs of M. smegmatis (total magnification, ×200,000). Column 1, parental M. smegmatis; column 2, Δlgt mutant; column 3, Δlgt-lgt_Mtb complemented strain; arrow, cytoplasmic membrane; square, electron-translucent layer; circle, electron-dense outer layer.