Degradation of polychlorinated biphenyl metabolites by naphthalene-catabolizing enzymes.
The ability of the dehydrogenase and ring cleavage dioxygenase of the naphthalene degradation pathway to transform 3,4-dihydroxylated biphenyl metabolites was investigated. 1,2-Dihydro-1, 2-dihydroxynaphthalene dehydrogenase was expressed as a histidine-tagged protein. The purified enzyme transformed 2, 3-dihydro-2,3-dihydroxybiphenyl, 3,4-dihydro-3,4-dihydroxybiphenyl, and 3,4-dihydro-3,4-dihydroxy-2,2',5,5'-tetrachlorobiphenyl to 2, 3-dihydroxybiphenyl, 3,4-dihydroxybiphenyl (3,4-DHB), and 3, 4-dihydroxy-2,2',5,5'-tetrachlorobiphenyl (3,4-DH-2,2',5,5'-TCB), respectively. Our data also suggested that purified 1, 2-dihydroxynaphthalene dioxygenase catalyzed the meta cleavage of 3, 4-DHB in both the 2,3 and 4,5 positions. This enzyme cleaved 3, 4-DH-2,2',5,5'-TCB and 3,4-DHB at similar rates. These results demonstrate the utility of the naphthalene catabolic enzymes in expanding the ability of the bph pathway to degrade polychlorinated biphenyls.
Barriault
D
D
INRS-Santé, Université du Québec, Pointe-Claire, Québec, Canada H9R 1G6.
Durand
J
J
Maaroufi
H
H
Eltis
L D
LD
Sylvestre
M
M
D001673:Biodegradation, Environmental; D049308:Dioxygenases; D004926:Escherichia coli / Q000201:enzymology*; D009281:Naphthalenes / Q000378:metabolism*; D010088:Oxidoreductases / Q000378:metabolism; D044925:Oxidoreductases Acting on CH-CH Group Donors; D010105:Oxygenases / Q000378:metabolism; D011078:Polychlorinated Biphenyls / Q000378:metabolism*; D011549:Pseudomonas / Q000201:enzymology*; D016958:Pseudomonas putida / Q000201:enzymology; D011994:Recombinant Proteins / Q000378:metabolism
D009281:Naphthalenes; D011994:Recombinant Proteins; D011078:Polychlorinated Biphenyls; D010088:Oxidoreductases; D010105:Oxygenases; C023133:dihydroxynaphthalene oxygenase; D049308:Dioxygenases; D044925:Oxidoreductases Acting on CH-CH Group Donors; C116788:cis-1,2-dihydro-1,2-dihydroxynaphthalene dehydrogenase