Reductive dechlorination of polychlorinated biphenyls as affected by natural halogenated aromatic compounds.
We investigated the effects of halogenated aromatic compounds (HACs) including naturally occurring ones (L-thyroxine, 3-chloro-L-tyrosine, 5-chloroindole, 2-chlorophenol, 4-chlorophenol and chlorobenzene) on polychlorinated biphenyl (PCB) dechlorination in sediment cultures. A PCB-dechlorinating enrichment culture of sediment microorganisms from the St. Lawrence River was used as an initial inoculum. When the culture was inoculated into Aroclor 1248 sediments amended with each of the six HACs, the extent of dechlorination was not enhanced by amendment with HACs. The dechlorination patterns in the HAC-amended sediments were nearly identical to that of the HAC-free sediments except the 3-chloro-L-tyrosine-amended ones where no dechlorination activity was observed. When these sediment cultures were transferred into fresh sediments with the same HACs, the dechlorination specificities remained the same as those of the initial inoculations. Thus, in the present study, the substrate range of the highly selected enrichment culture could not be broadened by the HACs. It appears that HACs affect PCB dechlorination mainly through population selection rather than enzyme induction of single population.
Division of Biological Sciences, University of Ulsan, Ulsan 680-749, Republic of Korea. jkim@mail.ulsan.ac.kr
Jongseol
J
Kim
Ahmi
A
Lee
Yong-Suk
YS
Moon
Jae-Seong
JS
So
Sung-Cheol
SC
Koh
D001140:Aroclors / Q000737:chemistry / Q000378:metabolism; D001673:Biodegradation, Environmental; D002713:Chlorine / Q000378:metabolism*; D019015:Geologic Sediments / Q000737:chemistry / Q000382:microbiology*; D006841:Hydrocarbons, Aromatic / Q000494:pharmacology*; D010084:Oxidation-Reduction; D011078:Polychlorinated Biphenyls / Q000737:chemistry / Q000378:metabolism*; D045483:Rivers / Q000737:chemistry / Q000382:microbiology*; D014874:Water Pollutants, Chemical / Q000378:metabolism
D001140:Aroclors; D006841:Hydrocarbons, Aromatic; D014874:Water Pollutants, Chemical; D002713:Chlorine; D011078:Polychlorinated Biphenyls