FIG. 5.

Integration of phoA into the chromosomes of M. smegmatis wild-type and porin mutants. (A) The phosphatase activity of M. smegmatis grown in liquid culture was determined by using pNPP. Black and gray bars indicate the phosphatase activity of whole and lysed cells, respectively. Error bars indicate standard deviations. (B) Phosphatase activity of M. smegmatis on Middlebrook 7H10 agar plates containing Tween 80 and BCIP. After 5 days of incubation, pictures of colonies were taken with a Zeiss stereomicroscope Stemi 2000-C using the same magnification for all strains. In both experiments, the strains were SMR5 (wild-type) and the porin mutants MN01 (ΔmspA) and ML10 (ΔmspA/mspC) and derivatives with an phoA expression cassette integrated at the attachment site of the phage L5 (attB::phoA). The blue color indicates the cleavage of BCIP by PhoA.