Title Molecular Characterization of Polychlorinated Biphenyl-Dechlorinating Populations in Contaminated Sediments
Author Kyoung-Hee Oh1,2, Ellen B. Ostrofsky3, and Young-Cheol Cho4*
Address 1School of Biological Sciences, Seoul National University, Seoul 151-742, Republic of Korea, 2Institute of Construction Technology, Chungbuk National University, Cheongju 361-763, Republic of Korea, 3School of Public Health, State University of New York at Albany, Albany, NY 12201, USA, 4Department of Environmental Engineering, Chungbuk National University, Cheongju 361-763, Republic of Korea
Bibliography Journal of Microbiology, 46(2),165-173, 2008,
DOI
Key Words polychlorinated biphenyls, reductive dechlorination, dechlorinating bacteria, amplified ribosomal DNA restriction analysis, restriction fragment length polymorphism
Abstract Polychlorinated biphenyl (PCB)-dechlorinating microorganisms were characterized in PCB-contaminated sediments using amplified ribosomal DNA restriction analysis (ARDRA). The sediments were prepared by spiking Aroclor 1248 into PCB-free sediments, and were inoculated with microorganisms eluted from St. Lawrence River sediments. PCB-free sediments inoculated with the same inoculum served as the control. Four restriction fragment length polymorphism (RFLP) groups in the eubacterial and two in the archaeal domain were found exclusively in PCB-spiked sediment clone libraries. Sequence analysis of the four eubacterial clones showed homology to Escherichia coli, Lactosphaera pasteurii, Clostridium thermocellum, and Dehalobacter restrictus. The predominant archaeal sequence in the PCB-spiked sediment clone library was closely related to Methanosarcina barkeri, which appear to support earlier findings that methanogens are involved in PCB dechlorination. When the dot-blot hybridization was performed between the sediment DNA extract and the probes designed with eubacterial RFLP groups, the intensity of two of eubacterial RFLP groups, which showed high sequence homology to C. pascui and D. restrictus, was highly correlated with the number of dechlorinating microorganisms suggesting these two members intend to contribute to PCB dechlorination.