Fig. 3.

Sulfatase activity profiling of mycobacterial species. Lysates were resolved by native gel electrophoresis before exposure to 25 μM DDAO-sulfate in buffer [50 mM Tris (pH 7.5 at 37 °C); 100 mM NaCl; 250 μM MnCl₂, MgCl₂, and CaCl₂]. Fluorescence imaging (excitation = 633, emission = 670 bp 30) revealed bands of DDAO fluorescence that are associated with sulfatase activity. Two laboratory strains, M. smegmatis and M. marinum, are indicated by a line at the top of the image. Species that can cause human pulmonary disease are indicated by a dashed line at the top of the gel. Members of the MTBC, including M. bovis, M. africanum, and M. tuberculosis, are labeled, with three strains of M. tuberculosis occupying the last three lanes. MW, molecular weight.