Department of Biochemistry and Microbiology, Rutgers University , New Brunswick, New Jersey 08901, United States.
Department of Marine and Coastal Science, Rutgers University , New Brunswick, New Jersey 08901, United States.
Environ Sci Technol. 2016 Feb 2;50(3):1455-64. doi: 10.1021/acs.est.5b04731. Epub 2016 Jan 15.
The widespread use of methyl tert-butyl ether (MTBE) has caused major contamination of groundwater sources and is a concern due to its taste and odor problems, as well as its toxicity. MTBE can be degraded anaerobically which makes bioremediation of contaminated aquifers a potential solution. Nevertheless, the organisms and mechanisms that are responsible for anaerobic MTBE degradation are still unknown. The aim of our research was to identify the organisms actively degrading MTBE. For this purpose we characterized an anaerobic methanogenic culture enriched with MTBE as the sole carbon source from the New Jersey Arthur Kill intertidal strait sediment. The cultures were analyzed using stable isotope probing (SIP) combined with terminal restriction fragment length polymorphism (T-RFLP), high-throughput sequencing and clone library analysis of bacterial 16S rRNA genes. The sequence data indicated that phylotypes belonging to the Ruminococcaceae in the Firmicutes were predominant in the methanogenic cultures. SIP experiments also showed sequential incorporation of the (13)C labeled MTBE by the bacterial community with a bacterium most closely related to Saccharofermentans acetigenes identified as the bacterium active in O-demethylation of MTBE. Identification of the microorganisms responsible for the activity will help us better understand anaerobic MTBE degradation processes in the field and determine biomarkers for monitoring natural attenuation.
甲基叔丁基醚(MTBE)的广泛使用导致了地下水水源的严重污染,由于其味道和气味问题以及毒性而引起了关注。MTBE 可以在厌氧条件下降解,这使得受污染含水层的生物修复成为一种潜在的解决方案。然而,负责厌氧 MTBE 降解的生物体和机制仍不清楚。我们的研究目的是确定积极降解 MTBE 的生物体。为此,我们从新泽西州阿瑟基尔潮汐海峡沉积物中用 MTBE 作为唯一碳源富集的厌氧产甲烷培养物进行了表征。使用稳定同位素探测(SIP)与末端限制性片段长度多态性(T-RFLP)、高通量测序和细菌 16S rRNA 基因克隆文库分析相结合对培养物进行了分析。序列数据表明,厚壁菌门中的瘤胃球菌科的类群在产甲烷培养物中占优势。SIP 实验还表明,细菌群落依次掺入(13)C 标记的 MTBE,与 Saccharofermentans acetigenes 最密切相关的细菌被鉴定为 MTBE 的 O-去甲基化活性细菌。鉴定出负责该活性的微生物将有助于我们更好地了解现场的厌氧 MTBE 降解过程,并确定用于监测自然衰减的生物标志物。