Subcellular localization of mycosin-1 in M. smegmatis -P1 and M. tuberculosis . Bacteria were isolated after three weeks (M. tuberculosis) or two days (M. smegmatis) of growth in culture. Bacterial cell lysates were subfractionated into cell wall (w), cell membrane (m), and intracellular (i) fractions. Fractions were resolved by SDS-PAGE and analyzed by Western blotting using anti-mycosin-1 antiserum. Molecular weights (in kDa) are indicated on the left.