FIG. 2.

Southern blot of IS903φkan insertions. Shown is the Southern blot of EcoRI-digested genomic DNA. Digoxigenin-labeled DNA containing the kan gene was used as a probe. The sizes of DNA markers are shown on the left in kilobases. The control lanes contain DNA from Y4Nal (lane 1), Y4Nal(pJAK17) (lane 2), Y4Nal(pVJT131) (lane 4), and Y4Nal(pVJT128) (lane 6). The bands observed in lanes 4 and 6 are due to hybridization with the pVJT parent plasmids. Kanamycin-resistant mutants were derived from Y4Nal(pJAK17) (lane 3), Y4Nal(pVJT131) (lane 5), and Y4Nal(pVJT128) (lanes 7 to 22). All mutants were cured of the parent plasmid.