FIG. 4.

Complementation of mutant strains with individual genes confirms that the Snm secretion pathway functions in M. smegmatis. (A and B) Various deletion strains were transformed with either an empty vector (pMJ13) or a multicopy episomal complementation plasmid constitutively expressing each individual gene C-terminally tagged with myc. In the case of Sm3882c and mycP1 complementation, the complementation plasmid expressed the individual genes tagged with 2× HA from the presumed endogenous promoter (505-bp fragment upstream of mycP1). (C) To test for M. tuberculosis (M.tb) ESAT-6 and CFP-10 secretion from M smegmatis, cells were transformed with pMH406, which complements the M. tuberculosis esxA/B deletion (10; data not shown). All cells were cultured in Sauton's medium with kanamycin, fractionated, and analyzed by Western blotting.