Degradation of Chlorinated Dibenzofurans and Dibenzo-p-Dioxins by Two Types of Bacteria Having Angular Dioxygenases with Different Features

Hiroshi Habe, Jin Sung Chung, Jong Hoon Lee, Kano Kasuga, Takako Yoshida, Hideaki Nojiri, Toshio Omori

Research output: Contribution to journalArticle

75 Scopus citations


Two kinds of bacteria having different-structured angular dioxygenases - a dibenzofuran (DF)-utilizing bacterium, Terrabacter sp. strain DBF63, and a carbazole (CAR)-utilizing bacterium, Pseudomonas sp. strain CA10 - were investigated for their ability to degrade some chlorinated dibenzofurans (CDFs) and chlorinated dibenzo-p-dioxins (CDDs) (or, together, CDF/Ds) using either wild-type strains or recombinant Escherichia coli strains. First, it was shown that CAR 1,9a-dioxygenase (CARDO) catalyzed angular dioxygenation of all monoto triCDF/Ds investigated in this study, but DF 4,4a-dioxygenase (DFDO) did not degrade 2,7-diCDD. Secondly, degradation of CDF/Ds by the sets of three enzymes (angular dioxygenase, extradiol dioxygenase, and meta-cleavage compound hydrolase) was examined, showing that these enzymes in both strains were able to convert 2-CDF to 5-chlorosalicylic acid but not other tested substrates to the corresponding chlorosalicylic acid (CSA) or chlorocatechol (CC). Finally, we tested the potential of both wild-type strains for cooxidation of CDF/Ds and demonstrated that both strains degraded 2-CDF, 2-CDD, and 2,3-diCDD to the corresponding CSA and CC. We investigated the sites for the attack of angular dioxygenases in each CDF/D congener, suggesting the possibility that the angular dioxygenation of 2-CDF, 2-CDD, 2,3-diCDD, and 1,2,3-triCDD (10 ppm each) by both DFDO and CARDO occurred mainly on the nonsubstituted aromatic nuclei.

Original languageEnglish (US)
Pages (from-to)3610-3617
Number of pages8
JournalApplied and environmental microbiology
Issue number8
StatePublished - Aug 1 2001


ASJC Scopus subject areas

  • Biotechnology
  • Food Science
  • Applied Microbiology and Biotechnology
  • Ecology

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