Characterization of cultures enriched from acidic polycyclic aromatic hydrocarbon-contaminated soil for growth on pyrene at low pH.
Two polycyclic aromatic hydrocarbon (PAH)-contaminated soils of pH 2 were successfully used as inoculum to enrich cultures growing on phenanthrene and pyrene at different pHs, including pH 3. Selected pyrene-utilizing cultures obtained at pH 3, pH 5, and pH 7 were further characterized. All showed rapid [14C]pyrene mineralization at pH 3 and pH 5 and grew on pyrene at pH values ranging from 2 to 6. Eubacterial and mycobacterial 16S rRNA gene denaturing gradient gel electrophoresis fingerprinting and sequencing indicated that the cultures were dominated by a single bacterium closely related to Mycobacterium montefiorense, belonging to the slow-growing Mycobacterium sp. In contrast, a culture enriched on pyrene at pH 7 from a slightly alkaline soil sampled at the same site was dominated by Pseudomonas putida and a fast-growing Mycobacterium sp. The M. montefiorense-related species dominating the pyrene-utilizing cultures enriched from the acidic soils was also the dominant Mycobacterium species in the acidic soils. Our data indicate that a slow-growing Mycobacterium species is involved in PAH degradation in that culture and show that bacteria able to degrade high-molecular-weight PAHs at low pH are present in acidic PAH-contaminated soil.
Uyttebroek
Maarten
M
Division Soil and Water Management, Catholic University of Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium.
Vermeir
Steven
S
Wattiau
Pierre
P
Ryngaert
Annemie
A
Springael
Dirk
D
D001419:Bacteria / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification* / Q000378:metabolism*; D001483:Base Sequence; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D009161:Mycobacterium / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism; D009691:Nucleic Acid Denaturation; D010616:Phenanthrenes / Q000378:metabolism; D010802:Phylogeny; D011084:Polycyclic Aromatic Hydrocarbons / Q000378:metabolism; D016958:Pseudomonas putida / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism; D011721:Pyrenes / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000378:metabolism*
D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D010616:Phenanthrenes; D011084:Polycyclic Aromatic Hydrocarbons; D011721:Pyrenes; D012336:RNA, Ribosomal, 16S; D012989:Soil Pollutants; C031181:phenanthrene; C030984:pyrene