Perfluoroalkyl Acids Inhibit Reductive Dechlorination of Trichloroethene by Repressing Dehalococcoides.
Perfluoroalkyl Acids Inhibit Reductive Dechlorination of Trichloroethene by Repressing Dehalococcoides.
复制标题
DOI：
10.1021/acs.est.5b04854
复制
发表时间：
2016-01
影响因子：
11.4
通讯作者：
T. Weathers;Katie C Harding-Marjanovic;C. Higgins;L. Alvarez-Cohen;J. Sharp
中科院分区：
文献类型：
--
作者：
T. Weathers;Katie C Harding-Marjanovic;C. Higgins;L. Alvarez-Cohen;J. Sharp
来自水性成膜泡沫的全氟烷基酸（PFAA）的表面下的可降解性可能会对用于混合氯化溶剂（如三氯乙烯（TCE））的生物修复的微生物过程产生不利影响。在这里，我们发现，当暴露于PFAA源区的代表性浓度（11种PFAA分析物，每种6 mg/L，总计>66 mg/L）时，产甲烷混合培养物的还原脱氯作用受到显著抑制。TCE脱氯，顺式二氯乙烯和氯乙烯的生产和脱氯，乙烯的产生都受到抑制，在这些PFAA浓度。系统发育分析表明，65%的操作分类单位（OTU）的丰度显着变化时，生长在PFAA的存在下，虽然抑制或增强PFAA曝光造成的不相关的推定功能或同源性。值得注意的是，存在对Dehalococcoides的显著抑制（丰度降低8倍），伴随着甲烷产生菌的相应增强（增加9倍）。生长和脱氯的无菌培养物的Dehalococcoides mccartyi菌株195同样在这些条件下抑制，证实了这个关键属PFAA存在的抑制反应。这些结果表明，氯化溶剂的生物衰减率可能会受到阻碍PFAA源区附近的地下环境。
The subsurface recalcitrance of perfluoroalkyl acids (PFAAs) derived from aqueous film-forming foams could have adverse impacts on the microbiological processes used for the bioremediation of co-mingled chlorinated solvents such as trichloroethene (TCE). Here, we show that reductive dechlorination by a methanogenic, mixed culture was significantly inhibited when exposed to concentrations representative of PFAA source zones (>66 mg/L total of 11 PFAA analytes, 6 mg/L each). TCE dechlorination, cis-dichloroethene and vinyl chloride production and dechlorination, and ethene generation were all inhibited at these PFAA concentrations. Phylogenetic analysis revealed that the abundances of 65% of the operational taxonomic units (OTUs) changed significantly when grown in the presence of PFAAs, although repression or enhancement resulting from PFAA exposure did not correlate with putative function or phylogeny. Notably, there was significant repression of Dehalococcoides (8-fold decrease in abundance) coupled with a corresponding enhancement of methane-generating Archaea (a 9-fold increase). Growth and dechlorination by axenic cultures of Dehalococcoides mccartyi strain 195 were similarly repressed under these conditions, confirming an inhibitory response of this pivotal genus to PFAA presence. These results suggest that chlorinated solvent bioattenuation rates could be impeded in subsurface environments near PFAA source zones.