Nucleic Acid Hybridization:DNA probe Plasmid Salmonella DNA fragment ③Unknown bacteria are collected ①A Salmonella DNA on a filter. fragment is cloned in E.coli. ④The cells are lysed, and the DNA is released. Cloned DNA fragments are marked with fluorescent dye and separated into single strands,forming The DNA is separated into DNA probes. single strands. L DNA probes are added to the DNA from the Fluorescent probe unknown bacteria. Salmonella DNA ⑦ DNA probes hybridize with Salmonella DNA from sample. Then excess probe is washed DNA from off-fluorescence indicates other bacteria presence of Salmonella. Figure 10.16Nucleic Acid Hybridization: DNA probe Figure 10.16