菲反硝化降解菌群的富集及其群落结构解析

发布时间：2018-05-13 13:48

  本文选题：菲 + 反硝化降解　； 参考：《环境科学学报》2017年11期

【摘要】：从潜在多环芳烃(Polycyclic Aromatic Hydrocarbons,PAHs)污染的油田区域采集土壤样品,以菲为唯一碳源且添加硝酸根的培养基来富集土壤中的菲反硝化降解菌群.随后,通过定量PCR(Polymerase Chain Reaction)测定了获取的富集菌群中反硝化相关功能基因(硝酸还原酶基因nar G、亚硝酸还原酶基因nir S)的丰度,并通过Illumina Mi Seq测序对其中的细菌群落结构进行解析.结果表明,获取到的3个菌群(PDN-1、PDN-2和PDN-3)12 d内对菲的降解率分别为45.18%、34.04%和25.92%.各富集培养菌群中nar G的丰度均高于nir S,且菲降解率最高的PDN-1中的反硝化相关基因丰度较低.Illumina Mi Seq测序结果表明,菲降解率最高的富集菌群PDN-1同时也具有较高的细菌多样性指数,变形菌门(Proteobacteria)、疣微菌门(Verrucomicrobia)和拟杆菌门(Bacteroidetes)是各富集菌群中的优势菌门,且Proteobacteria在3个富集菌群PDN-1(97.78%)、PDN-2(96.57%)、PDN-3(93.90%)中的比例均最高.变形菌门的Pseudomonas(γ-Proteobacteria)和Methylophilus(β-Proteobacteria)则是各富集菌群中最大的优势菌属,前者为公认的PAHs降解菌,而后者则为能够利用还原型"一碳化合物"的特殊菌属.细菌多样性与菲的降解率呈正相关,表明菲的反硝化降解可能是多种细菌参与的共同结果.上述结果可为揭示典型PAHs反硝化降解的微生物机制提供理论依据,同时为深入研究反硝化与菲代谢的偶联机理打下基础.
[Abstract]:Soil samples were collected from potential polycyclic Aromatic hydrocarbonates (PAHs) contaminated oil fields. Phenanthrene was used as the sole carbon source and nitrate was added to enrich the phenanthrene denitrification bacteria community in the soil. Then, the abundance of denitrification-related functional genes (nar G and nir S) were determined by quantitative PCR(Polymerase Chain reaction, and the community structure was analyzed by Illumina Mi Seq sequencing. The results showed that the degradation rates of phenanthrene in PDN-1PDN-2 and PDN-3)12 d were 45.18% and 25.92%, respectively. The abundance of nar G in all enriched cultures was higher than that of nir, and the denitrification-related gene abundance in PDN-1 with the highest phenanthrene degradation rate was lower. Illumina Mi Seq sequencing results showed that, The enriched PDN-1 with the highest phenanthrene degradation rate also had a high bacterial diversity index. Proteobacteria, Verrucomicrobia, Verrucomicrobia and Bacteroidetes) were the dominant bacteria in each enriched flora, and Proteobacteria had the highest proportion among the three enriched bacteria PDN-197.787.757. Pseudomonas (纬 -Proteobacteria) and Methylophilus (尾 -Proteobacteria) are the most dominant bacteria in each enriched flora. The former is recognized as PAHs degrading bacteria, while the latter is a special genus which can utilize reduced carbon compounds. The diversity of bacteria was positively correlated with the degradation rate of phenanthrene, indicating that denitrification of phenanthrene might be the common result of many bacteria involved. These results can provide a theoretical basis for revealing the microbial mechanism of typical denitrification degradation of PAHs and lay a foundation for further study on the coupling mechanism between denitrification and phenanthrene metabolism.
【作者单位】： 西南大学资源环境学院;
【基金】：国家自然科学基金(No.41371477) 中央高校基本科研业务费专项(No.XDJK2014B047) 西南大学光炯创新实验项目(No.2016012)~~
【分类号】：X172;X53
，

本文编号：1883397