[芘降解细菌群落培养过程中的种群迁移及降解特性]

[Population shift and degrading characteristics of a pyrene-degrading bacterial consortium during incubation process].

作者信息

Li Xiaoming, Zhang Mingjiang, Jin Jinghua, Liu Shuangjiang, Jiang Chengying

机构信息

Institute of Microbiology, State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.

出版信息

Wei Sheng Wu Xue Bao. 2012 Oct 4;52(10):1260-7.

PMID:23289325

Abstract

OBJECTIVE

The work aimed to obtain pyrene-degrading bacterial consortium and use it for bioremediation of polycyclic aromatic hydrocarbons-contaminated soil.

METHODS

We enriched and incubated a bacterial consortium utilizing pyrene as the sole carbon source from the contaminated soil of Beijing Coking Chemical Plant. We analyzed the degrading ability and growth of the consortium by high performance liquid chromatography (HPLC) and spectrophotometer. We investigated the degradation activities of the consortium after several times transfer and freeze-drying deposit. We also investigated the shift of bacterial consortium composition after several times transfer by combining of culture-dependent and culture-independent methods. We constructed and analyzed the 16S rRNA gene clone libraries at different transfer times (3 times PYR-3, 6 times PYR-6 and 9 times PYR-9) for monitoring the bacterial population changes.

RESULTS

The degradation rate of pyrene, phenanthrene and fluoranthene reached 89%, 86% and 49% respectively after incubation of the consortium for 12 days. The degradation activities of the consortium were stable after several times transfer and freeze-drying deposit. We isolated nine strains from the consortium, affiliated to genus of Achromobacter, Bacillus, Arthrobacter, Exiguobacterium and Parapedobacter. Phylogenetic analyses showed that Proteobacteria were the main group at contaminated soil sample (100%) and bacterial consortium incubated in pyrene (PYR-3, 83%). Bacterial community structure was shifted and biodiversity was increased during the transfer process, the proportions of gamma-Proteobacteria was decreased from 77% (PYR-3) to 33% (PYR-6) and 18% (PYR-9), while beta-Proteobacteria increased from 13% (PYR-3) to 36% (PYR-6) and 55% (PYR-9).

CONCLUSION

The bacterial consortium could utilize pyrene as sole carbon and energy source for growth and the degradation ability for pyrene was stable.

摘要

目的

本研究旨在获得芘降解细菌群落，并将其用于多环芳烃污染土壤的生物修复。

方法

从北京焦化厂污染土壤中富集培养以芘为唯一碳源的细菌群落。采用高效液相色谱（HPLC）和分光光度计分析该群落的降解能力和生长情况。研究该群落经过多次传代和冻干保存后的降解活性。还通过依赖培养和不依赖培养的方法相结合，研究多次传代后细菌群落组成的变化。构建并分析不同传代次数（3次传代的PYR-3、6次传代的PYR-6和9次传代的PYR-9）时的16S rRNA基因克隆文库，以监测细菌种群变化。

结果

该群落培养12天后，芘、菲和荧蒽的降解率分别达到89%、86%和49%。经过多次传代和冻干保存后，该群落的降解活性稳定。从该群落中分离出9株菌株，分别属于无色杆菌属、芽孢杆菌属、节杆菌属、微小杆菌属和副鞘氨醇杆菌属。系统发育分析表明，变形菌门是污染土壤样品中的主要菌群（100%），也是在芘中培养的细菌群落（PYR-3，83%）中的主要菌群。在传代过程中细菌群落结构发生变化，生物多样性增加，γ-变形菌门的比例从77%（PYR-3）降至33%（PYR-6）和18%（PYR-9），而β-变形菌门从13%（PYR-3）增至36%（PYR-6）和55%（PYR-9）。