Hot oil reservoirs harbor diverse microbial communities, with many of them inhabiting thermophilic or hyperthermophilic fermentative Thermotogae species. A new Thermotoga sp. strain TFO was isolated from an Californian offshore oil reservoir which is phylogenetically related to thermophilic species T. petrophila RKU-1^T and T. naphthophila RKU-10^T, isolated from the Kubiki oil reservoir in Japan. The average nucleotide identity and DNA–DNA hybridization measures provide evidence that the novel strain TFO is closely related to T. naphthophila RKU-10^T, T. petrophila RKU-1^T and can not be differentiated at the species level. In the light of these results, the reclassification of T. naphthophila RKU-10 and strain TFO as heterotypic synonyms of T. petrophila is proposed. A pangenomic survey of closely related species revealed 55 TFO strain-specific proteins, many of which being linked to glycosyltransferases and mobile genetic elements such as recombinases, transposases and prophage, which can contribute to genome evolution and plasticity, promoting bacterial diversification and adaptation to environmental changes. The discovery of a TFO-specific transport system dctPQM, encoding a tripartite ATP-independent periplasmic transporter (TRAP), has to be highlighted. The presence of this TRAP system assumes that it could assist in anaerobic n-alkane degradation by addition of fumarate dicarboxylic acid, suggesting a niche-specific gene pool which correlates with the oil reservoir that T. petrophila TFO inhabits. Finally, T. naphthophila RKU-10, T. petrophila RKU-1^T, T. petrophila TFO form a distinct phylogenetic lineage with different geographic origins, share the same type of ecological niche including the burial history of fields. Theses findings might support the indigenous character of this species in oil reservoirs.

热油藏藏着各种各样的微生物群落，其中许多栖息于嗜热或超嗜热的发酵嗜热菌种。新的Thermotoga sp。TFO菌株是从加利福尼亚的离岸油库中分离出来的，该油库与嗜热菌T. petrophila RKU-1 ^T和T. naphthophila RKU-10 ^T的亲缘关系从日本Kubiki油库中分离出来。平均核苷酸同一性和DNA–DNA杂交方法提供了证据，表明新型菌株TFO与^嗜油杆菌RKU-10 ^T，^嗜油杆菌RKU-1 ^T密切相关并且无法在物种级别上进行区分。在这些结果的基础上，重新分类T. naphthophila RKU-10和应变TFO作为异型同义词T. petrophila被提议。对密切相关物种的一次全基因组调查显示，共有55种TFO菌株特异性蛋白，其中许多与糖基转移酶和可移动遗传元件（如重组酶，转座酶和前噬菌体）相关，可促进基因组进化和可塑性，促进细菌多样化和适应环境变化。TFO特定的运输系统dctPQM的发现非常重要，该系统编码不依赖于三方ATP的周质转运蛋白（TRAP）。该TRAP系统的存在假定它可以通过添加富马酸酯二羧酸来帮助厌氧正构烷烃降解，这表明了一个利基特异性基因库，该基因库与T. petrophila TFO所居住的油藏相关。最后，嗜油杆菌RKU-10，T。petrophila RKU-1 ^T，T。petrophila TFO形成了独特的系统发育谱系，具有不同的地理起源，共有相同类型的生态位，包括田地的埋葬历史。这些发现可能支持该物种在油藏中的土著特征。