Biphenyl/Chlorobiphenyls catabolic pathway of Comamonas testosteroni B-356: Prospect for use in bioremediation

This review summarizes our present knowledge concerning bacterial PCB oxidative catabolic pathways. Using, as an example, some of the results that were obtained mainly with Comamonas testosteroni B-356, some of the major features of PCB catabolic pathways will be depicted. Based on our present knowledge, some of the factors that should be considered in priority when looking for strategies to obtain new strains with enhanced capabilities to degrade those persistent pollutants will be discussed. The major features that will be discussed include the bioavailability of PCB as substrate, the use of co-substrate, the significance of the substrate reactivity pattern of the biphenyl oxygenase (the first enzyme of the pathway) and the importance of the stringent control of metabolite production.