title: Isolation and characterization of polycyclic aromatic hydrocarbon-degrading Mycobacterium isolates from soil.
abstract: Bioremediation of soils contaminated with wood preservatives containing polycyclic aromatic hydrocarbons (PAHs) is desired because of their toxic, mutagenic, and carcinogenic properties. Creosote wood preservative-contaminated soils at the Champion International Superfund Site in Libby, Montana currently undergo bioremediation in a prepared-bed land treatment unit (LTU) process. Microbes isolated from these LTU soils rapidly mineralized the (14)C-labeled PAH pyrene in the LTU soil. Gram staining, electron microscopy, and 16S rDNA-sequencing revealed that three of these bacteria, JLS, KMS, and MCS, were Mycobacterium strains. The phylogeny of the 16S rDNA showed that they were distinct from other Mycobacterium isolates with PAH-degrading activities. Catalase and superoxide dismutase (SOD) isozyme profiles confirmed that each isolate was distinct from each other and from the PAH-degrading mycobacterium, Mycobacterium vanbaalenii sp. nov, isolated from a petroleum-contaminated soil. We find that dioxygenase genes nidA and nidB are present in each of the Libby Mycobacterium isolates and are adjacent to each other in the sequence nidB-nidA, an order that is unique to the PAH-degrading mycobacteria.
authors.affiliation: Department of Biology, Utah State University, Logan, UT 84322, USA. cdmiller@biology.usu.edu
authors.forename: C D
authors.initials: CD
authors.lastname: Miller
authors.forename: K
authors.initials: K
authors.lastname: Hall
authors.forename: Y N
authors.initials: YN
authors.lastname: Liang
authors.forename: K
authors.initials: K
authors.lastname: Nieman
authors.forename: D
authors.initials: D
authors.lastname: Sorensen
authors.forename: B
authors.initials: B
authors.lastname: Issa
authors.forename: A J
authors.initials: AJ
authors.lastname: Anderson
authors.forename: R C
authors.initials: RC
authors.lastname: Sims
mesh_terms: D001483:Base Sequence; D001673:Biodegradation, Environmental; D002250:Carbon Radioisotopes; D002374:Catalase / Q000378:metabolism; D016000:Cluster Analysis; D017931:DNA Primers; D004275:DNA, Ribosomal / Q000235:genetics; D007527:Isoenzymes; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D009009:Montana; D009161:Mycobacterium / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D010802:Phylogeny; D011084:Polycyclic Aromatic Hydrocarbons / Q000378:metabolism*; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology; D013045:Species Specificity; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D002250:Carbon Radioisotopes; D017931:DNA Primers; D004275:DNA, Ribosomal; D007527:Isoenzymes; D011084:Polycyclic Aromatic Hydrocarbons; D002374:Catalase; D013482:Superoxide Dismutase