Sequence similarities in the genes encoding polychlorinated biphenyl degradation by Pseudomonas strain LB400 and Alcaligenes eutrophus H850.

DNA-DNA hybridization was used to compare the Pseudomonas strain LB400 genes for polychlorinated biphenyl (PCB) degradation with those from seven other PCB-degrading strains. Significant hybridization was detected to the genome of Alcaligenes eutrophus H850, a strain similar to LB400 in PCB-degrading capability. These two organisms showed a strong conservation of restriction sites in the region of DNA encoding PCB metabolism. No other sequence similarities were detected in the two genomes. DNA from the other PCB-degrading strains showed no hybridization to the probe, which demonstrated the existence of at least two distinct classes of genes encoding PCB degradation.