Johnsen Anders R, Winding Anne, Karlson Ulrich, Roslev Peter
National Environmental Research Institute, Department of Environmental Chemistry and Microbiology, DK-4000 Roskilde, Denmark.
Appl Environ Microbiol. 2002 Dec;68(12):6106-13. doi: 10.1128/AEM.68.12.6106-6113.2002.
Phenanthrene-metabolizing soil microbial communities were characterized by examining mineralization of [(14)C]phenanthrene, by most-probable-number (MPN) counting, by 16S-23S spacer DNA analysis of the numerically dominant, culturable phenanthrene-degrading isolates, and by examining incorporation of [(13)C]phenanthrene-derived carbon into sterols and polar lipid fatty acids (PLFAs). An unpolluted agricultural soil, a roadside soil diffusely polluted with polycyclic aromatic hydrocarbons (PAHs), and two highly PAH-polluted soils from industrial sites were analyzed. Microbial phenanthrene degraders were not detected by MPN counting in the agricultural soil and the roadside soil. In the industrial soils, phenanthrene degraders constituted 0.04 and 3.6% of the total number of CFU. 16S-23S spacer DNA analysis followed by partial 16S DNA sequencing of representative isolates from one of the industrial soils showed that one-half of the isolates belonged to the genus Sphingomonas and the other half were closely related to an unclassified beta-proteobacterium. The (13)C-PLFA profiles of the two industrial soils were relatively similar and resembled the profiles of phenanthrene-degrading Sphingomonas reference strains and unclassified beta-proteobacterium isolates but did not match the profiles of Pseudomonas, Mycobacterium, or Nocardia reference strains. The (13)C-PLFA profiles of phenanthrene degraders in the agricultural soil and the roadside soil were different from each other and different from the profiles of the highly polluted industrial soils. Only in the roadside soil were 10me/12me18:0 PLFAs enriched in (13)C, suggesting that actinomycetes metabolized phenanthrene in this soil. The (13)C-PLFA profiles of the unpolluted agricultural soil did not resemble the profiles of any of the reference strains. In all of the soils investigated, no excess (13)C was recovered in the 18:2omega6,9 PLFA, suggesting that fungi did not contribute significantly to assimilation of [(13)C]phenanthrene.
通过检测[¹⁴C]菲的矿化、采用最大可能数（MPN）计数法、对数量上占优势的可培养菲降解分离株进行16S - 23S间隔区DNA分析以及检测[¹³C]菲衍生碳掺入甾醇和极性脂质脂肪酸（PLFA）的情况，对菲代谢土壤微生物群落进行了表征。分析了一种未受污染的农业土壤、一种受多环芳烃（PAH）轻度污染的路边土壤以及两种来自工业场地的高PAH污染土壤。在农业土壤和路边土壤中，通过MPN计数未检测到微生物菲降解菌。在工业土壤中，菲降解菌分别占总菌落形成单位（CFU）数的0.04%和3.6%。对其中一种工业土壤的代表性分离株进行16S - 23S间隔区DNA分析，随后进行部分16S DNA测序，结果表明一半的分离株属于鞘氨醇单胞菌属，另一半与一种未分类的β - 变形杆菌密切相关。两种工业土壤的¹³C - PLFA图谱相对相似，类似于菲降解鞘氨醇单胞菌参考菌株和未分类β - 变形杆菌分离株的图谱，但与假单胞菌、分枝杆菌或诺卡氏菌参考菌株的图谱不匹配。农业土壤和路边土壤中菲降解菌的¹³C - PLFA图谱彼此不同，也与高污染工业土壤的图谱不同。仅在路边土壤中，10me/12me18:0 PLFA的¹³C含量有所富集，表明放线菌在该土壤中代谢菲。未受污染的农业土壤的¹³C - PLFA图谱与任何参考菌株的图谱均不相似。在所有调查的土壤中，18:2ω6,9 PLFA中均未检测到过量的¹³C，这表明真菌对[¹³C]菲的同化作用不显著。
