FIG. 4.

(A) TLC of M. tuberculosis H37Rv MPLA activity by cellular location using [¹⁴C]dipalmitoyl PC (DPPC) labeled on both palmitic acids. The presence of [¹⁴C]FA and [¹⁴C]LPC indicates hydrolysis of [¹⁴C]dipalmitoyl PC from PLA activity. WC, whole cells; CS, culture supernatant; CW, cell wall; CM, cell membrane; C, cytosol; A₂, snake venom PLA₂. Results were consistent with those in panel B. (B) MPLA activity of M. tuberculosis H37Rv by cellular location on cutinase substrate NPB in μmol per mg protein. Activity is predominantly in cell membrane and cell wall in both the PLA and the cutinase assays. CFP, culture filtrate protein.