An excellent study by Watanabe and coworkers used a combination of molecular biological and microbiological
methods to detect and characterize the dominant phenol-degrading bacteria in activated sludge. TGGE analysis of
PCR products of 16s rDNA and of the gene encoding phenol hydroxylase (LmPH) showed a few dominant bacterial
populations after a 20 day incubation with phenol. Comparison of sequences of different bacterial isolates and excised TGGE bands revealed two dominant bacterial strains responsible for the phenol degradation.