FIG. 1.

Partial restriction maps of the H. ducreyi 35000 cdtABC gene cluster in pJL300 and related constructs. Plasmid pJL300 was constructed by inserting the PCR-derived 3-kb cdtABC gene cluster into the EcoRI site in pBR322. Plasmid pJL303 was constructed by inserting a cat cartridge into the BseRI site in the cdtC gene within pJL300. Plasmid pJL300-C was constructed by inserting the 813-bp PCR product containing the cdtC open reading frame into the EcoRI site within pLS88. Oligonucleotide primers P1 to P6 are indicated and are described in detail in Materials and Methods. The open arrow indicates the direction of transcription. Restriction sites in parentheses are vector-based sites and are not present in H. ducreyi chromosomal DNA. A 1-kb size marker is indicated on the lower left.