Genetic and serological evidence for the recognition of four pentachlorophenol-degrading bacterial strains as a species of the genus Sphingomonas

Summary Four pentachlorophenol (PCP)-degrading bacterial strains: Arthrobacter sp. ATCC 33790, Pseudomonas sp. SR3, Flavobacterium sp. ATCC 39723 and Pseudomonas sp. RA2; were analyzed by 16S rRNA gene sequence comparisons, REP/ERIC PCR fingerprinting of genomic DNA and serological typing by reaction to antisera prepared against each strain. The results of the analyses suggest that a close phylogenetic relationship exists between these four PCP-degrading strains, all of which were determined to cluster within the existing genus Sphingomonas , and support the recognition of Arthrobacter sp. ATCC 33790 and Pseudomonas sp. SR3, Flavobacterium sp. ATCC 39723 and Pseudomonas sp. RA2 as a separate Sphingomonas species. A gene probe, prepared by PCR-amplification of the PCP-4-monooxygenase gene (pcpB) of Flavobacterium sp. ATCC 39723, was used to group PCP-degrading strains on the basis of hybridization to the gene probe: all strains of the Gram-negative, PCP-degrading Sphingomonas spp. hybridized to the gene probe, whereas Gram-positive PCP-degrading strains analyzed did not hybridize to the gene probe.