分子生态学方法对油藏细菌群落结构分析的比较

目前对油藏细菌群落结构分析方法繁多,为得到准确全面的群落分析结果,必须选取合适的方法。群落分析方法的优劣进行比较分析,选取从新疆陆梁油田注水井筛出的11株单菌,测定其16srDNA序列,制成包含7个菌属、9个菌种的混合菌液。应用基于PCR扩增的三种分子生态技术DGGE、T-RFLP、建立16SrDNA文库比较和分析了混合菌液细菌多样性。使用PCR-DGGE方法时发现,DGGE方法可灵敏地检测到序列1 bp的变化,能将不同菌株分开,但该方法经过切胶测序后的的目标序列较短,信息量不大且有时有一定误差,较适合用于定性对比;而用于菌群结构的分析时应结合其他方法。T-RFLP法可区分大部分菌属,但数据库不够完整,不能确定细菌群落组成;因此也不适合单独用在细菌群落检测中,可用作多个样品种群多样性的对比或结合其他方法对样品进行系统透彻解析。建立16srDNA克隆文库法成功鉴定到7个菌属8个菌种16SrDNA序列,更适用于油藏细菌群落结构的分析。

Comparison of molecular ecology methods in the analysis of bacterial community in reservoir

There are many methods for analysis of bacterial community structure in reservoir now. It must select a appropriate method for accurate and comprehensive analysis of bacterial community. The study was comparison of advantages and disadvantages of methods of community analysis. We selected and sequenced 11 strains from the bacteria obtained from water injection well in Xinjiang Luliang oil well. A mixture of bacterium suspension compounded by the 11 strains contains 7 different bacteria species and 9 different strains. Using three PCR-based molecular ecological techniques, i.e. DGGE, T-RFLP and construction of 16S rDNA clone library , the bacterial community diversity of the mixture was investigated and compared. In the DGGE profiles, 16S rDNA high variable region from the same specie or strain cannot reach the same stripe, while the high variable region from a variety bacteria of different species of which similarity had multiple differences can reach the same stripe. So the best use of DGGE in the examination is as an initial means of gene mutation detection but not the analysis of bacterial community. T-RFLP can separating a great mount of bacteria species. But the database for it is not complete , so that T-RFLP cannot determine the bacteria species that sample contains. So T-RFLP is not suitable for detection of the bacterial community alone, it can use for contrast of community structure diversity in multiple samples or analysis detailedly in combination with other methods. Through the construction of 16S rDNA clone library, we identified successful 16S rDNA sequences of 7 different bacteria species and 8 different stains. In summary, the method of 16S rDNA clone library construction is more appropriate for analysis of bacterial community in reservoir.