Aerobic degradation of highly chlorinated PCBs by a marine bacterium, Pseudomonas CH07

Aerobic degradation of PCBs though have been reported to be limited to less chlorinated biphenyls (PCBs), we report here of a marine mercury-resistant bacterium, Pseudomonas CH07 (NRRL B30604) which was capable of degrading a variety of highly chlorinated congeners of PCBs from the technical mixture Clophen A-50. Of the two most toxic coplanar PCBs present in Clophen A-50, one coplanar pentachloro congener CB-126 and one toxic sterically hindered heptachloro congener CB-181 were found to be degraded completely and the other coplanar tetrachloro congener CB-77 was degraded by more than 40% within 40 hours by this microorganism. Apparently absence of bphC in this bacterium led to proposition of different mechanism of PCBs degradation.