Figure 3

Fluorescence In Situ Hybridization (FISH) with a specific whole genome probe on methanol:acetic acid fixed and spread cultures from E. coli treated with ampicillin. DAPI counterstaining (blue) evidences a faint background of aggregated material that encloses the bacteria that appear more strongly stained (a). The whole genome probe, revealed with Cy 3, red, labelled the nucleoids from bacteria and strongly hybridized with the aggregated background (b).