PCB (PoylChlorinated Bisphenyls) are among the longlasting environmental toxins. They are present in varying degrees all over. It has been very difficult to identify bacteria which can degradate this chemical highly inert products enzymatically.
This weeks PNAS (doi: 10.1073/pnas.1404845111 ) describes for the first time the cultivation of organisms which can be reliably kept in culture and which feed on PCB. The authors show three Dehalococcoides mccartyi strains with different dechlorination potential and slight differences in the genome. The enzyme involved is a Reductive Dehalogenase which sequences have been determined and which are active in a bioassay removing chlorine from both PCB and PCE.
This may be a novel step in the search for decontamination, however, given that the process so far in under anaerobis conditions, it is mere speculation that this enzyme will work under ambient conditions.