Quantification of Aromatic Oxygenase Genes to Evaluate Enhanced Bioremediation by Oxygen Releasing Materials at a Gasoline-Contaminated Site
Quantification of Aromatic Oxygenase Genes to Evaluate Enhanced Bioremediation by Oxygen Releasing Materials at a Gasoline-Contaminated Site
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DOI：
10.1021/es900146f
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发表时间：
2009-03-15
影响因子：
11.4
通讯作者：
Nakatsu, Cindy H.
中科院分区：
文献类型：
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作者：
Nebe, Jennifer;Baldwin, Brett R.;Nakatsu, Cindy H.
地下注射释氧物质(ORM)通常是在石油污染的地方进行的，以刺激苯、甲苯、乙苯和二甲苯(BTEX)的好氧生物修复。在这项研究中，芳香族加氧酶基因的qPCR计数和细菌16S rRNA基因的PCR-DGGE图谱与地下水监测相结合，以确定注入ORM对汽油污染场地BTEX生物修复的影响。在注入前，苯系物浓度大于3 mg/L，DO水平通常小于2 mg/g，但在受影响井中检测到苯酚羟基酶(Phe)和环羟基甲苯单加氧酶(RMO)基因，表明苯系物具有好氧生物降解的潜力。注射后，BTEX浓度显著下降，Phe和RMO基因拷贝数增加1-3个数量级。此外，在DO增加期间，间歇性地检测到萘双加氧酶(NAH)和二甲苯单加氧酶(TOL)基因。随着ORM的耗尽，DO减少，BTEX浓度回升，加氧酶基因不再被检测到。PCRDGGE微生物群落剖面的时间变化反映了地下条件的动态变化。总体而言，化学和地化分析与芳香族加氧酶基因的定量相结合表明，注射刺激了BTEX的生物降解，直到ORM耗尽。
Subsurface injection of oxygen-releasing materials (ORMs) is frequently performed at petroleum-contaminated sites to stimulate aerobic bioremediation of benzene, toluene, ethylbenzene, and xylenes (BTEX). In this study, qPCR enumeration of aromatic oxygenase genes and PCR-DGGE profiles of bacterial 16S rRNA genes were combined with groundwater monitoring to determine the impact of ORM injection on BTEX bioremediation at a gasoline-contaminated site. Prior to injection, BTEX concentrations were greater than 3 mg/L and DO levels were typically less than 2 mg/but phenol hydroxylase (PHE) and ring-hydroxylating toluene monooxygenase (RMO) genes were detected in impacted wells indicating the potential for aerobic BTEX biodegradation. Following injection, 00 increased, BTEX concentrations decreased substantially, and PHE and RMO genes copies increased by 1-3 orders of magnitude. In addition, naphthalene dioxygenase (NAH) and xylene monooxygenase (TOL) genes were intermittently detected during periods of increased DO. Following depletion of the ORM, DO decreased, BTEX concentrations rebounded, and oxygenase genes were no longer detected. Temporal changes in PCR-DGGE microbial community profiles reflected the dynamic changes in subsurface conditions. Overall, the combination of chemical and geochemical analyses with quantification of aromatic oxygenase genes demonstrated that injection stimulated BTEX biodegradation until the ORM was depleted.