胜利油藏不同时间细菌群落结构的比较

Comparison of bacterial community structures in Shengli oil reservoir of different time point

摘要:

利用聚合酶链式反应-变性梯度凝胶电泳(PCR-DGGE)和构建16S rRNA基因克隆文库2种方法, 对孤岛油田两口井(注水井G和采油井L)在相距9个月的2个时间点(A和B)所采集样品的细菌群落结构进行了比较。DGGE图谱聚类分析表明注水井在2个时间点的微生物群落结构相似性为48.1%, 而采油井的相似性只有28.7%。16S rRNA基因克隆文库结果表明, A时间点样品G中的优势菌群为Betaproteobacteria、Gammaproteobacteria, 还有Deferribacteres、Firmicutes、Bacteroidetes等; 而样品L中, Gammaproteobacteria中的Moraxellaceae含量达到97%。B时间点G中除了优势菌Betaproteobacteria之外, Deferribacteres的数量显著增加, 成为优势菌; 而L在B时间点优势菌除Gammaproteobacteria外, 还有Betaproteobacteria和Firmicutes。采油井中的微生物群落结构随时间发生了显著改变, 而注水井变化不显著。这一结果部分揭示了微生物采油过程中地层微生物群落的变化规律, 有助于进一步阐明微生物驱油的机理。

Abstract:

Denaturing gradient gel electrophoresis (PCR-DGGE) and 16S rRNA gene clone library methods were used to analyze the microbial communities of a water injection well (G) and an oil production well (L) at two sampling time points (A and B) in Gudao block of Shengli oilfield. DGGE profile showed that the microbial similarity of sample G at two sampling time was 48.1%, that of sample L was 28.7%, respectively. Sequence analysis of 16S rRNA gene clone libraries showed that bacteria in G library at time point A were mainly Betaproteobacteria and Gammaproteobacteria, and also with low percentage of Deferribacteres, Firmicutes and Bacteroidetes; But in L library, 97% bacteria belong to Moraxellaceae of Gammaproteobacteria. Whereas, the main type of bacteria in sample G at time point B were Betaproteobacteria and Deferribacteres. The bacterial composition of sample L was dominated by Gammaproteobacteria, Betaproteobacteria and Firmicutes. Both DGGE and clone library indicated the distinct temporary shift of microbial communities of production well, but much less change happened in injection water sample. Our results will benefit to the better understanding of mechanisms of microbial enhanced oil recovery.