title: Transformation of hydroxylated derivatives of 2,5-dichlorobiphenyl and 2,4,6-trichlorobiphenyl by Burkholderia xenovorans LB400.
abstract: The polychlorinated biphenyl (PCB)-degrading bacterium, Burkholderia xenovorans LB400, was capable of transforming three hydroxylated derivatives of 2,5-dichlorobiphenyl (2,5-DCB) (2'-hydroxy- (2'-OH-), 3'-OH-, and 4'-OH-2,5-DCB) when biphenyl was used as the carbon source (i.e., biphenyl pathway-inducing condition), although only 2'-OH-2,5-DCB was transformed when the bacterium was growing on succinate (i.e., condition non-inductive of the biphenyl pathway). On the contrary, hydroyxlated derivatives of 2,4,6-trichlorobiphenyl (2,4,6-TCB) (2'-OH-, 3'-OH-, and 4'-OH-2,4,6-TCB) were not significantly transformed by B. xenovorans LB400, regardless of the carbon source used. Gene expression analyses showed a clear correlation between the transformation of OH-2,5-DCBs and expression of genes of the biphenyl pathway. The PCB metabolite, 2,5-dichlorobenzoic acid (2,5-DCBA), was produced following the transformation of OH-2,5-DCBs. 2,5-DCBA was not further transformed by B. xenovorans LB400. The present study is significant because it provides evidence that PCB-degrading bacteria are capable of transforming hydroxylated derivatives of PCBs, which are increasingly considered as a new class of environmental contaminants.
authors.affiliation: Department of Civil and Environmental Engineering, Temple University, Philadelphia, PA, 19122, USA.
authors.forename: Rouzbeh
authors.initials: R
authors.lastname: Tehrani
authors.forename: Monica M
authors.initials: MM
authors.lastname: Lyv
authors.forename: Benoit
authors.initials: B
authors.lastname: Van Aken
mesh_terms: D001711:Biotransformation; D019117:Burkholderia / Q000378:metabolism*; D002723:Chlorobenzoates / Q000378:metabolism*; D004785:Environmental Pollutants / Q000378:metabolism*; D006900:Hydroxylation; D011078:Polychlorinated Biphenyls / Q000378:metabolism*
chemical_list: D002723:Chlorobenzoates; D004785:Environmental Pollutants; C102834:2,4,6-trichlorobiphenyl; C029905:2,5-dichlorobiphenyl; D011078:Polychlorinated Biphenyls; C073069:2,5-dichlorobenzoic acid