Isolation and identification of mycobacteria from soils at an illegal dumping site and landfills in Japan.
In order to study the diversity and community of genus Mycobacterium in polluted soils, we tried to isolate mycobacteria from 11 soil samples collected from an illegal dumping site and 3 landfills in Japan. Using culture methods with or without Acanthamoeba culbertsoni, a total of 19 isolates of mycobacteria were obtained from 5 soil samples and 3 of them were isolated only by the co-culture method with the amoeba. Conventional biochemical tests and sequencing of the hsp65, rpoB, and 16S rRNA genes were performed for species identification of 17 of the 19 isolates. Among the 17 isolates, there was one isolate each of Mycobacterium vanbaalenii, Mycobacterium mageritense, Mycobacterium frederiksbergense, M. vanbaalenii or Mycobacterium austroafricanum, and Mycobacterium chubuense or Mycobacterium chlorophenolicum. The remaining 12 isolates could not be precisely identified at the species level. A phylogenic tree based on the hsp65 sequences indicated that 2 of the 12 isolates were novel species. In addition, 4 isolates were phylogenically close to species that degrade polycyclic aromatic hydrocarbons, which induce some cancers in humans. These results demonstrated that there were many hitherto-unreported mycobacteria in the polluted soils, and suggested that some mycobacteria might play roles in the natural attenuation and engineered bioremediation of contaminated sites with other microorganisms.
Wang
Yan
Y
Department of Microbiology, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Fukuoka, Japan.
Ogawa
Midori
M
Fukuda
Kazumasa
K
Miyamoto
Hiroshi
H
Taniguchi
Hatsumi
H
D000048:Acanthamoeba / Q000382:microbiology; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics; D018834:Chaperonin 60; D018833:Chaperonins / Q000235:genetics; D012321:DNA-Directed RNA Polymerases; D007564:Japan; D009161:Mycobacterium / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D010641:Phenotype; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012037:Refuse Disposal; D012988:Soil Microbiology
D001426:Bacterial Proteins; D018834:Chaperonin 60; D012336:RNA, Ribosomal, 16S; C074119:heat-shock protein 65, Mycobacterium; C505805:rpoB protein, Mycobacterium tuberculosis; D012321:DNA-Directed RNA Polymerases; D018833:Chaperonins