FIG. 1.

Diagram of H. ducreyi hemolysin gene region from strain 35000, the hemolysin-negative derivative of strain 35000, constructs containing the hhdA and hhdB genes, and locations of primers and probes used in this study. Restriction sites used for cloning that were added as a result of PCR amplification or from multiple cloning sites are underlined. The cat cassette, used to replace the PstI fragment internal to the hhdA gene in 35000ΔAPC, is necessarily not drawn to scale. U32175 is the GenBank accession number for hhdB and hhdA (35); numbers on the diagram indicate base pairs.