FIG. 1.
Southern blot analysis and hybridization profile of the M. bovis BCG purC mutant. The hybridization profiles of the DNA of Kmr transformants obtained in two independent experiments are shown. Lane 1 corresponds to the M. bovis BCG purC mutant MYC1552; lanes 2 to 4 correspond to transformants which have undergone a single crossover event at the purC locus in another experiment; lane 5 is the wild-type (WT) strain M. bovis BCG 1173P2. Chromosomal DNA were digested with BamHI and probed for hybridization with the purC gene (1,090-bp EcoRV-HincII fragment from pMJ1).