油烟污染对土壤假单胞菌种群多样性的影响

Effects of oil fume pollution on the diversity and community structure of Pseudomonas populations in soils

目的确定油烟污染土壤中假单胞菌种群结构的组成情况。方法采用未培养技术直接从长期受油烟污染的土壤样品中提取微生物基因组总DNA,构建基于假单胞菌特异性引物PCR扩增的16S rRNA基因克隆文库,通过HaeⅢ限制性内切酶对基因文库的克隆进行限制性片段多态性分析(ARDRA)。结果随着油烟污染的加剧,油烟污染区土壤中假单胞菌多样性指数显著升高,其优势种群主要是P.putida,P.stuzeri,P.fluorescens和P.aeruginosa。结论在长期污染胁迫下,4种假单胞菌分别得到了不同程度的富集,推测可能与油烟的自然降解有一定的相关性。

Aim The diversity and community structure of Pseudomonas populations was analysed.Methods Total microbial DNA was directly extracted from oil fume contaminated soils of Xi′an,Shaanxi province.The clone library of 16 S ribosomal RNA genes was amplified using PCR with specific Pseudomonas primer sets.The PCR products were then subcloned into pGM-T vector.Each unique restriction fragment polymorphism pattern,created by using restriction endonucleases HaeⅢ,was designated as an operational taxonomic unit（OTU）.Results The results showed that the Shannon diversity index of Pseudomonas was significantly higher with the aggravation of oil fume contamination.Conclusion Pseudomonas phylogenetic trees of 16SrRNA gene indicated that P.putida,P.stuzeri,P.fluorescens and P.aeruginosa were the dominant species in oil fume contaminated soils,demonstrating that these four species were enriched under the stress of oil fume pollution,which might correlate with the natural degradation of oil fume.