Co-metabolic degradation of chlorinated hydrocarbons by Pseudomonas sp strain DCA1

Pseudomonas sp. strain DCA1, which is capable of utilizing 1,2-dichloroetha ne (DCA) as sole carbon and energy source, was used to oxidize chlorinated methanes, ethanes, propanes, and ethenes. Chloroacetic acid, an intermediat e in the DCA degradation pathway of strain DCA1, was used as a co-substrate since it was readily oxidized by DCA-grown cells of strain DCA1 and did no t compete for the monooxygenase. All of the tested compounds except tetrach loroethylene (PER) were oxidized by cells expressing DCA monooxygenase. Str ain DCA1 could not utilize any of these compounds as a growth substrate. Co -metabolic oxidation during growth on DCA was studied with 1,2-dichloroprop ane. Although growth on this mixture occurred, 1,2-dichloropropane strongly inhibited growth of strain DCA1. This inhibition was not caused by competi tion for the monooxygenase. It was shown that the oxidation of 1,2-dichloro propane resulted in the accumulation of 2,3-dichloro-1-propanol and 2-chlor oethanol.