title: Degradation of aroclor 1242 dechlorination products in sediments by Burkholderia xenovorans LB400(ohb) and Rhodococcus sp. strain RHA1(fcb).
abstract: Burkholderia xenovorans strain LB400, which possesses the biphenyl pathway, was engineered to contain the oxygenolytic ortho dehalogenation (ohb) operon, allowing it to grow on 2-chlorobenzoate and to completely mineralize 2-chlorobiphenyl. A two-stage anaerobic/aerobic biotreatment process for Aroclor 1242-contaminated sediment was simulated, and the degradation activities and genetic stabilities of LB400(ohb) and the previously constructed strain RHA1(fcb), capable of growth on 4-chlorobenzoate, were monitored during the aerobic phase. The population dynamics of both strains were also followed by selective plating and real-time PCR, with comparable results; populations of both recombinants increased in the contaminated sediment. Inoculation at different cell densities (10(4) or 10(6) cells g(-1) sediment) did not affect the extent of polychlorinated biphenyl (PCB) biodegradation. After 30 days, PCB removal rates for high and low inoculation densities were 57% and 54%, respectively, during the aerobic phase.
authors.affiliation: NSF Center for Microbial Ecology, 540 Plant and Soil Science Building, Michigan State University, East Lansing, MI 48824, USA.
authors.forename: Jorge L M
authors.initials: JL
authors.lastname: Rodrigues
authors.forename: C Alan
authors.initials: CA
authors.lastname: Kachel
authors.forename: Michael R
authors.initials: MR
authors.lastname: Aiello
authors.forename: John F
authors.initials: JF
authors.lastname: Quensen
authors.forename: Olga V
authors.initials: OV
authors.lastname: Maltseva
authors.forename: Tamara V
authors.initials: TV
authors.lastname: Tsoi
authors.forename: James M
authors.initials: JM
authors.lastname: Tiedje
mesh_terms: D001140:Aroclors / Q000378:metabolism*; D001673:Biodegradation, Environmental; D019117:Burkholderia / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D002713:Chlorine / Q000378:metabolism; D002723:Chlorobenzoates / Q000378:metabolism; D004785:Environmental Pollutants / Q000378:metabolism*; D005818:Genetic Engineering / Q000379:methods; D019015:Geologic Sediments / Q000382:microbiology*; D009876:Operon; D011078:Polychlorinated Biphenyls / Q000378:metabolism; D011995:Recombination, Genetic; D012240:Rhodococcus / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D012989:Soil Pollutants / Q000378:metabolism
chemical_list: D001140:Aroclors; D002723:Chlorobenzoates; D004785:Environmental Pollutants; D012989:Soil Pollutants; D002713:Chlorine; C027423:aroclor 1242; D011078:Polychlorinated Biphenyls