College of Environment and Ecology, Chongqing University, Chongqing 400045, China; Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China.
College of Environment and Ecology, Chongqing University, Chongqing 400045, China; Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China.
Ecotoxicol Environ Saf. 2021 Dec 1;225:112740. doi: 10.1016/j.ecoenv.2021.112740. Epub 2021 Sep 2.
The land-based oil extraction activity has led to serious pollution of the soil. While microbes may play an important role in the remediation of contaminated soils, ecological effects of oil pollution on soil microbial relationships remain poorly understood. Here, typical contaminated soils and undisturbed soils from seven oilfields of China were investigated in terms of their physicochemical characteristics, indigenous microbial assemblages, bacterial co-occurrence patterns, and metabolic enzymes. Network visualization based on k-core decomposition illustrated that oil pollution reduced correlations between co-existing bacteria. The core genera were altered to those related with oil metabolism (Pseudarthrobacter, Alcanivorax, Sphingomonas, Chromohalobacter and Nocardioides). Under oil pollution pressure, the indigenous bacteria Gammaproteobacteria was domesticated as biomarker and the enzyme expression associated with the metabolism of toxic benzene, toluene, ethylbenzene, xylene and polycyclic aromatic hydrocarbons was enhanced. Functional pathways of xenobiotics biodegradation were also stimulated under oil contamination. Finally, twelve culturable hydrocarbon-degrading microbes were isolated from these polluted soils and classified into Stenotrophomonas, Delftia, Pseudomonas and Bacillus. These results show that the soil microbial communities are transformed under oil pollution stress, and also provide useful information for future bioremediation processes.
陆地石油开采活动导致了严重的土壤污染。虽然微生物在污染土壤的修复中可能发挥着重要作用，但石油污染对土壤微生物关系的生态影响仍知之甚少。在这里，我们研究了来自中国七个油田的典型污染土壤和未受干扰的土壤，从其理化特性、土著微生物群落、细菌共生模式和代谢酶方面进行了研究。基于 k-核分解的网络可视化表明，石油污染降低了共存细菌之间的相关性。核心属被改变为与石油代谢有关的属（假单胞菌、Alcanivorax、鞘氨醇单胞菌、Chromohalobacter 和诺卡氏菌）。在石油污染压力下，土著细菌γ变形菌被驯化成为生物标志物，与有毒苯、甲苯、乙苯、二甲苯和多环芳烃代谢相关的酶表达增强。在石油污染下，异生物降解的功能途径也得到了刺激。最后，从这些污染土壤中分离出了 12 株可培养的烃类降解微生物，并将其分类为寡养单胞菌、德氏菌、假单胞菌和芽孢杆菌。这些结果表明，土壤微生物群落在石油污染胁迫下发生了转化，也为未来的生物修复过程提供了有用的信息。
