Li Shanshan, Li Danni, Yan Wei
Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049, China.
Environ Sci Pollut Res Int. 2015 Jul;22(13):10196-205. doi: 10.1007/s11356-015-4211-6. Epub 2015 Feb 21.
The release of methyl tert-butyl-ether (MTBE) into the environment has increased the worldwide concern about the pollution of MTBE. In this paper, a microbial consortium was isolated from the soil sample near an oil station, which can degrade MTBE directly with a low biomass yield and MTBE degrading efficiency. Further research has indicated that this consortium can degrade MTBE efficiently when grown on n-octane as the cometabolic substrate. The results of 16S rDNA based on phylogenetic analysis of the selected operating taxonomic units (OTUs) involved in the consortium revealed that one OTU was related to Pseudomonas putida GPo1, which could cometabolically degrade MTBE on the growth of n-octane. This may help explain why n-octane could be the optimal cometabolic substrate of the consortium for MTBE degradation. Furthermore, the degradation of MTBE was observed along with the consumption of n-octane. Different K s values for MTBE were observed for cells grown with or without n-octane, suggesting that different enzymes are responsible for the oxidation of MTBE in cells grown on n-octane or MTBE. The results are discussed in terms of their impacts on our understanding of MTBE biodegradation and cometabolism.
甲基叔丁基醚(MTBE)向环境中的释放增加了全球对MTBE污染的关注。本文从一个加油站附近的土壤样本中分离出一个微生物群落,该群落能够以低生物量产量直接降解MTBE且具有MTBE降解效率。进一步的研究表明,当以正辛烷作为共代谢底物生长时,这个群落能够高效降解MTBE。基于对该群落中选定的操作分类单元(OTUs)进行系统发育分析的16S rDNA结果显示,一个OTU与恶臭假单胞菌GPo1相关,其能够在正辛烷生长时共代谢降解MTBE。这可能有助于解释为什么正辛烷可能是该群落降解MTBE的最佳共代谢底物。此外,观察到MTBE的降解与正辛烷的消耗同时发生。对于在有或没有正辛烷的情况下生长的细胞,观察到MTBE有不同的Ks值,这表明在以正辛烷或MTBE生长的细胞中,不同的酶负责MTBE的氧化。从这些结果对我们理解MTBE生物降解和共代谢的影响方面进行了讨论。