Enriching for microbial reductive dechlorination of polychlorinated dibenzo-p-dioxins and dibenzofurans.
Anaerobic enrichment cultures derived from contaminated Kymijoki River sediments dechlorinated 1,2,3,4-tetrachlorodibenzofuran (1,2,3,4-tetra-CDF), octachlorodibenzofuran (octa-CDF) and 1,2,3,4-tetrachlorodibenzo-p-dioxin (1,2,3,4-tetra-CDD). 1,2,3,4-tetra-CDF was dechlorinated via 1,2,3-, 2,3,4-, and 1,3,4/1,2,4-tri-CDFs to 1,3-, 2,3-, and 2,4-di-CDFs and finally to 4-mono-CDF. The dechlorination rate of 1,2,3,4-tetra-CDF was generally slower than that of 1,2,3,4-tetra-CDD. The rate and extent of 1,2,3,4-tetra-CDD dechlorination was enhanced by addition of pentachloronitrobenzene (PCNB) as a co-substrate. Dechlorination of spiked octa-CDF was observed with the production of hepta-, hexa-, penta- and tetra-CDFs over 6 months. Two major phylotypes of the Chloroflexi community showed an increase, one of which was identical to the Dehalococcoides mccartyi Pinellas subgroup. A set of twelve putative reductive dehalogenase (rdh) genes increased in abundance with addition of 1,2,3,4-tetra-CDF, 1,2,3,4-tetra-CDD and/or PCNB. This information will aid in understanding how indigenous microbial communities impact the fate of PCDFs and in developing strategies for bioremediation of PCDD/F contaminated sediments.
Department of Biochemistry and Microbiology, School of Environmental and Biological Sciences, Rutgers University, The State University of New Jersey, 76 Lipman Drive, New Brunswick, NJ 08901, USA.
Hui
H
Liu
Joong-Wook
JW
Park
Max M
MM
Häggblom
D001572:Benzofurans / Q000032:analysis / Q000378:metabolism*; D001673:Biodegradation, Environmental; D041862:Chloroflexi / Q000235:genetics / Q000502:physiology; D000072338:Dibenzofurans, Polychlorinated; D019015:Geologic Sediments / Q000737:chemistry / Q000382:microbiology; D000072317:Polychlorinated Dibenzodioxins / Q000031:analogs & derivatives* / Q000032:analysis / Q000378:metabolism; D045483:Rivers / Q000737:chemistry / Q000382:microbiology; D014871:Water Microbiology
D001572:Benzofurans; D000072338:Dibenzofurans, Polychlorinated; D000072317:Polychlorinated Dibenzodioxins
Anaerobic dechlorination; Chlorodibenzofurans; Dehalococcoides; Sediment