Regiospecificity of dioxygenation of di- to pentachlorobiphenyls and their degradation to chlorobenzoates by the bph-encoded catabolic pathway of Burkholderia sp. strain LB400

The biphenyl dioxygenase of Burkholderia sp. strain LB400 dioxygenates polychlorobiphenyls at different positions on the ring depending on the placement of substituents. The 2,4-disubstituted ring is dioxygenated at positions 2 and 3, whereas the 2,5-dichlorinated ring is dioxygenated at positions 3 and 4.