College of Urban Environment, Lanzhou City University, Lanzhou 730070, China; Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Gansu Province, 730000, China.
State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy Sciences, Lanzhou 730000, China; Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Gansu Province, 730000, China.
Gene. 2022 May 20;823:146368. doi: 10.1016/j.gene.2022.146368. Epub 2022 Feb 28.
The Tibetan Plateau niche provides unprecedented opportunities to find microbes that are functional and commercial significance. The present study investigated the physiological and genomic characteristics of Planococcus halotolerans Y50 that was isolated from a petroleum-contaminated soil sample from the Qinghai-Tibet Plateau, and it displayed psychrotolerant, antiradiation, and oil-degraded characteristics. Whole genome sequencing indicated that strain Y50 has a 3.52 Mb genome and 44.7% G + C content, and it possesses 3377 CDSs. The presence of a wide range of UV damage repair genes uvrX and uvsE, DNA repair genes radA and recN, superoxide dismutase, peroxiredoxin and dioxygenase genes provided the genomic basis for the adaptation of the plateau environment polluted by petroleum. Related experiments also verified that the Y50 strain could degrade n-alkanes from C-C, and approximately 30% of the total petroleum at 25 °C within 7 days. Meanwhile, strain Y50 could withstand 5 × 10 J/m UVC and 10 KGy gamma ray radiation, and it had strong antioxidant and high radical scavengers for superoxide anion, hydroxyl radical and DPPH. In addition, pan-genome analysis and horizontal gene transfers revealed that strains with different niches have obtained various genes through horizontal gene transfer in the process of evolution, and the more similar their geographical locations, the more similar their members are genetically and ecologically. In conclusion, P. halotolerans Y50 possesses high potential of applications in the bioremediation of alpine hydrocarbons contaminated environment.
青藏高原小生境为寻找具有功能和商业意义的微生物提供了前所未有的机会。本研究从青藏高原受石油污染的土壤样本中分离到一株耐盐菌 Planococcus halotolerans Y50，该菌具有耐冷、抗辐射和降解石油的特性。全基因组测序表明，菌株 Y50 基因组大小为 3.52 Mb，GC 含量为 44.7%，包含 3377 个 CDS。存在广泛的 UV 损伤修复基因 uvrX 和 uvsE、DNA 修复基因 radA 和 recN、超氧化物歧化酶、过氧化物酶和双加氧酶基因，为适应青藏高原受石油污染的环境提供了基因组基础。相关实验还验证了 Y50 菌株可以在 25°C 下 7 天内降解 C-C 范围内的正烷烃，降解率约为 30%的总石油烃。同时，Y50 菌株可以耐受 5×10 J/m UVC 和 10 KGy 伽马射线辐射，具有较强的抗氧化能力和较高的超氧阴离子、羟基自由基和 DPPH 自由基清除能力。此外，泛基因组分析和水平基因转移表明，不同小生境的菌株在进化过程中通过水平基因转移获得了各种基因，地理位置越相似，其成员在遗传和生态上就越相似。总之，P. halotolerans Y50 具有在高山烃污染环境的生物修复中应用的巨大潜力。
