FIG. 2.

Southern blot analysis (A) and mapping of the insertions into the ssa1 gene (B) of four representative transposon mutants. (A) Genomic DNA of N. meningitidis Z5463 (WT) and of four mutants (1 to 4) resulting from transposition into the ssa1 gene was digested with ClaI and probed with the 1.5-kbp PCR fragment corresponding to ssa1 that was used as a target for transposition. Molecular sizes are indicated in kilobase pairs. (B) Distribution of the insertions on the ClaI restriction map of the ssa1 genomic locus. The sequences of the insertion sites are highlighted, and the target dinucleotide that is duplicated upon transposition is underlined.