title: Sphingomonas sp. strain KA1, carrying a carbazole dioxygenase gene homologue, degrades chlorinated dibenzo-p-dioxins in soil.
abstract: Hybridization analysis showed that a newly isolated carbazole (CAR)-degrading bacterium Sphingomonas sp. strain KA1 did not possess the gene encoding the terminal oxygenase component (carAa) of CAR 1,9a-dioxygenase at high homology (more than 90% identity) to that of another CAR-degrader, Pseudomonas resinovorans strain CA10. However, PCR experiments using the primers for amplifying the internal fragment of the carAa gene (810 bp for strain CA10) showed that a PCR product of unexpected size (1100 bp) was amplified. Sequence analysis revealed that this DNA region contained the portion of two possible ORFs, which showed moderate homology to CarAa and CarBa from strain CA10 (61% and 40% identities at the amino acid level, respectively). Inoculation of strain KA1 into dioxin-contaminated model soil resulted in 96% and 70% degradation of 2-mono- and 2,3-dichlorinated dibenzo-p-dioxin, respectively, after 7-day incubation.
authors.affiliation: Biotechnology Research Center, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, 113-8657, Tokyo, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Habe
authors.forename: Yuji
authors.initials: Y
authors.lastname: Ashikawa
authors.forename: Yuko
authors.initials: Y
authors.lastname: Saiki
authors.forename: Takako
authors.initials: T
authors.lastname: Yoshida
authors.forename: Hideaki
authors.initials: H
authors.lastname: Nojiri
authors.forename: Toshio
authors.initials: T
authors.lastname: Omori
mesh_terms: D001426:Bacterial Proteins; D015139:Blotting, Southern; D004147:Dioxins / Q000032:analysis / Q000378:metabolism*; D049308:Dioxygenases; D005798:Genes, Bacterial / Q000235:genetics; D016366:Open Reading Frames / Q000235:genetics; D010105:Oxygenases / Q000235:genetics* / Q000378:metabolism*; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012689:Sequence Homology, Nucleic Acid; D012987:Soil / Q000032:analysis*; D012988:Soil Microbiology; D020578:Sphingomonas / Q000145:classification / Q000201:enzymology* / Q000235:genetics* / Q000302:isolation & purification
chemical_list: D001426:Bacterial Proteins; D004147:Dioxins; D012336:RNA, Ribosomal, 16S; D012987:Soil; D010105:Oxygenases; D049308:Dioxygenases; C108434:carbazole 1,9a-dioxygenase