Bian Xin-Yu, Mbadinga Serge Maurice, Liu Yi-Fan, Yang Shi-Zhong, Liu Jin-Feng, Ye Ru-Qiang, Gu Ji-Dong, Mu Bo-Zhong
1] State Key Laboratory of Bioreactor Engineering and Institute of Applied Chemistry, East China University of Science and Technology, Shanghai, P.R. China [2] Shanghai Collaborative Innovation Center for Biomanufacturing Technology, Shanghai 200237, P.R. China.
School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong, P.R. China.
Sci Rep. 2015 May 13;5:9801. doi: 10.1038/srep09801.
Anaerobic degradation of alkanes in hydrocarbon-rich environments has been documented and different degradation strategies proposed, of which the most encountered one is fumarate addition mechanism, generating alkylsuccinates as specific biomarkers. However, little is known about the mechanisms of anaerobic degradation of alkanes in oil reservoirs, due to low concentrations of signature metabolites and lack of mass spectral characteristics to allow identification. In this work, we used a multidisciplinary approach combining metabolite profiling and selective gene assays to establish the biodegradation mechanism of alkanes in oil reservoirs. A total of twelve production fluids from three different oil reservoirs were collected and treated with alkali; organic acids were extracted, derivatized with ethanol to form ethyl esters and determined using GC-MS analysis. Collectively, signature metabolite alkylsuccinates of parent compounds from C1 to C8 together with their (putative) downstream metabolites were detected from these samples. Additionally, metabolites indicative of the anaerobic degradation of mono- and poly-aromatic hydrocarbons (2-benzylsuccinate, naphthoate, 5,6,7,8-tetrahydro-naphthoate) were also observed. The detection of alkylsuccinates and genes encoding for alkylsuccinate synthase shows that anaerobic degradation of alkanes via fumarate addition occurs in oil reservoirs. This work provides strong evidence on the in situ anaerobic biodegradation mechanisms of hydrocarbons by fumarate addition.
在富含烃类的环境中，烷烃的厌氧降解已有文献记载，并且提出了不同的降解策略，其中最常见的是富马酸加成机制，生成烷基琥珀酸作为特定的生物标志物。然而，由于标志性代谢物浓度低且缺乏用于鉴定的质谱特征，人们对油藏中烷烃厌氧降解的机制知之甚少。在这项工作中，我们采用了一种多学科方法，结合代谢物谱分析和选择性基因检测来确定油藏中烷烃的生物降解机制。总共收集了来自三个不同油藏的十二份采出液并用碱处理；提取有机酸，用乙醇衍生化形成乙酯，并使用气相色谱 - 质谱分析进行测定。从这些样品中共同检测到了从C1到C8母体化合物的标志性代谢物烷基琥珀酸及其（假定的）下游代谢物。此外，还观察到了指示单环和多环芳烃厌氧降解的代谢物（2 - 苄基琥珀酸、萘酸盐、5,6,7,8 - 四氢萘酸盐）。烷基琥珀酸和编码烷基琥珀酸合酶的基因的检测表明，油藏中通过富马酸加成发生烷烃的厌氧降解。这项工作为通过富马酸加成进行原位厌氧生物降解烃类的机制提供了有力证据。
