DNA probes specific for Aeromonas hydrophila (HG1)

Aeromonas hydrophila (HG1)-specific RAPD-PCR fragments were investigated fo r their potential as DNA probes. From 20 RAPD-PCR fragment bands, it was fo und that two were specific to all isolates of Aeromonas hydrophila (HG1) te sted. Cloning and nucleotide sequence determination of one of these bands s howed that co-migration of similar sized amplicons had occurred and that th is band (designated '7e') contained at least four fragments of different se quences. Three of these individual amplicons had a sequence specific to Aer . hydrophila (HG1) isolates. The sequence of one of these amplicons ('7e5') was used to design primers for a specific polymerase chain reaction (PCR). The specificity of the PCR was achieved using a modified hot-start procedu re. The identity of the PCR amplicons was confirmed by high stringency hybr idization with a digoxygenin-labelled 7e5 probe.