Insights into the anaerobic biodegradation pathway of n-Alkanes in oil reservoirs by detection of signature metabolites

TY - JOUR

T1 - Insights into the anaerobic biodegradation pathway of n-Alkanes in oil reservoirs by detection of signature metabolites

AU - Bian, Xin Yu

AU - Mbadinga, Serge Maurice

AU - Liu, Yi Fan

AU - Yang, Shi Zhong

AU - Liu, Jin Feng

AU - Ye, Ru Qiang

AU - Gu, Ji Dong

AU - Mu, Bo Zhong

N1 - Funding Information: This work was supported by the National Natural Science Foundation of China (No. 51174092, 41373070) and the NSFC/RGC Joint Research Fund (No. 41161160560).

PY - 2015/5/13

Y1 - 2015/5/13

N2 - 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.

AB - 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.

UR - http://www.scopus.com/inward/record.url?scp=84929353273&partnerID=8YFLogxK

U2 - 10.1038/srep09801

DO - 10.1038/srep09801

M3 - 文章

C2 - 25966798

AN - SCOPUS:84929353273

SN - 2045-2322

VL - 5

JO - Scientific Reports

JF - Scientific Reports

M1 - 9801

ER -