PDF(Pubmed)
Abstract：
Microbes from oil reservoirs shape petroleum composition through processes such as biodegradation or souring. Such processes are considered economically detrimental and might pose health and safety hazards. It is therefore crucial to understand the composition of a reservoir\'s microbial community and its metabolic capabilities. However, such analyses are hindered by difficulties in extracting DNA from such complex fluids as crude oil. Here, we present a novel DNA extraction method from oils with a wide American Petroleum Institute (API) gravity (density) range. We investigated the ability to extract cells from oils with different solvents and surfactants, the latter both nonionic and ionic. Furthermore, we evaluated three DNA extraction methods. Overall, the best DNA yields and the highest number of 16S rRNA reads were achieved with isooctane as a solvent, followed by an ionic surfactant treatment using sodium dodecyl sulfate and DNA extraction using the PowerSoil Pro Kit (Qiagen). The final method was then applied to various oils from oil reservoirs collected in aseptic conditions. Despite the expected low cell density of 101-103 cells/ml, the new method yielded reliable results, with average 16S rRNA sequencing reads in the order of 41431 (±8860) per sample. Thermophilic, halophilic, and anaerobic taxa, which are most likely to be indigenous to the oil reservoir, were found in all samples. API gravity and DNA yield, despite the sufficient DNA obtained, did not show a correlation.
摘要：
来自油藏的微生物通过诸如生物降解或酸化的过程形成石油组合物。这种方法被认为在经济上是有害的,并且可能造成健康和安全危害。因此，了解水库微生物群落的组成及其代谢能力至关重要。然而,从原油等复杂流体中提取DNA的困难阻碍了这种分析。这里,我们提出了一种新颖的从石油中提取DNA的方法，具有广泛的美国石油学会（API）重力（密度）范围。我们研究了用不同的溶剂和表面活性剂从油中提取细胞的能力，后者是非离子和离子。此外，我们评估了三种DNA提取方法。总的来说,以异辛烷为溶剂可获得最佳的DNA产量和最高的16SrRNA读数，随后使用十二烷基硫酸钠进行离子表面活性剂处理,并使用PowerSodicPro试剂盒(Qiagen)进行DNA提取。然后将最终方法应用于来自在无菌条件下收集的储油器的各种油。尽管预期101-103细胞/ml的低细胞密度，新方法产生了可靠的结果，每个样品的平均16SrRNA测序读数为41431(±8860)。嗜热,嗜盐,和厌氧分类单元，最有可能是油藏的土著，在所有样本中都有发现。API重力和DNA产量，尽管获得了足够的DNA，没有显示出相关性。
