Oil reservoirs contain microbial populations that are both autochthonously and allochthonously introduced by industrial development. These microbial populations are greatly influenced by external factors including, but not limited to, salinity and temperature. In this study, we used metagenomics to examine the microbial populations within five wells of the same hydrocarbon reservoir system in the Gulf of Mexico. These elevated salinity (149–181 ppt salinity, 4–5× salinity of seawater) reservoirs have limited taxonomic and functional microbial diversity dominated by methanogens, Halanaerobium and other Firmicutes lineages, and contained less abundant lineages such as Deltaproteobacteria. Metagenome assembled genomes (MAGs) were generated and analyzed from the various wells. Methanogen MAGs were closely related to Methanohalophilus euhalobius, a known methylotrophic methanogen from a high salinity oil environment. Based on metabolic reconstruction of genomes, the Halanaerobium perform glycine betaine fermentation, potentially produced by the methanogens. Industrial introduction of methanol to prevent methane hydrate formation to this environment is likely to be consumed by these methanogens. As such, this subsurface oil population may represent influences from industrial processes.

储油库中的微生物种群是通过工业发展而自发地和异源地引入的。这些微生物种群受到外部因素的极大影响，这些外部因素包括但不限于盐度和温度。在这项研究中，我们使用宏基因组学来检查墨西哥湾同一油气藏系统的5口井中的微生物种群。这些盐度较高（盐度为149-181 ppt，海水盐度为4-5倍）的储层，其分类学和功能微生物多样性有限，主要是产甲烷菌，ana以及其他Firmicutes世系，并且包含数量较少的世系，例如Deltaproteobacteria。从各个孔中生成并分析了元基因组组装的基因组（MAG）。产甲烷镁与嗜甲烷嗜盐菌是一种来自高盐油环境的已知甲基营养型产甲烷菌。基于基因组的代谢重建，ana进行可能由产甲烷菌产生的甘氨酸甜菜碱发酵。这些产甲烷物质可能会消耗工业上引入的甲醇来防止甲烷水合物形成到该环境中。因此，这种地下油藏可能代表了工业过程的影响。