In situ detection of rhodococci associated with activated sludge foams

Genus-specific 16S rRNA targeted oligonucleotide probes, Rco1 and Rco2, wer e designed and used to detect rhodococci in activated sludge foam samples b y confocal laser scanning microscopy. Pure cultures were used to find the o ptimal hybridisation conditions which were determined by comparing the mean fluorescent intensities of target and non-target cells from images capture d using a confocal laser scanning microscope (CLSM). The combination of flu orescent in situ hybridisation with rRNA-targeted oligonucleotide probes an d confocal laser scanning microscopy provides an effective way of detecting rhodococci in environmental samples.