摘要
6∶2氟调醇(6∶2 FTOH)是一种多氟烷基物质,近年被广泛用于工业和消费品中,对环境有潜在威胁,但目前关于6∶2FTOH及其降解产物对沉积物中微生物群落结构的影响还不清楚.本研究的目的是通过基因分析方法探索6∶2 FTOH生物降解对表层沉积物中细菌群落结构的影响.从天津海河采集表层沉积物和河水,在实验室进行微宇宙实验,通过LC-MS/MS测定6∶2 FTOH及其降解产物的浓度,通过变性梯度凝胶电泳和高通量测序分析细菌的群落结构.结果表明,6∶2 FTOH在微生物的作用下可发生降解(半衰期小于3 d),生成6∶2 FTCA、6∶2 FTUCA等中间产物和5∶2 FT Ketone、5∶2 s FTOH、PFHx A、PFPe A、PFBA、5∶3 Acid等稳定产物,该过程对沉积物细菌群落结构产生明显影响,引起细菌群落丰富度和多样性的变化.在6∶2 FTOH降解的不同阶段,细菌的变化和优势菌群略有不同.根据100 d的实验结果,从门的分类水平看,6∶2 FTOH生物降解引起绿弯菌门丰度大幅上升(+24.8%)、变形菌门和厚壁菌门丰度大幅下降(-17.8%和-15.9%).从纲的分类水平看,6∶2 FTOH生物降解引起丰度上升较大的有厌氧绳菌纲(+19.6%)和δ-变形菌纲(+4.3%),引起丰度下降较大的有ε-变形菌纲(-20.0%)、梭菌纲(-10.1%)、芽孢杆菌纲(-5.8%)和γ-变形菌纲(-4.2%).从属的分类水平看,6∶2 FTOH生物降解引起丰度上升较大的有Anaerolineaceae_uncultured(+19.1%)和硫碱球菌属(+13.3%),引起丰度下降较大的有弧菌属(-14.1%)、硫单胞菌属(-13.2%)、芽孢杆菌属(-5.1%)、Sulfurovum(-4.2%)和Fusibacter(-4.1%).这些结果有助于预测环境中细菌对多氟烷基物质污染的响应及筛选可降解多氟烷基物质的细菌.
Fluorotelomer alcohol（6 ∶ 2 FTOH） is a polyfluoalkyl substance that has been widely used in industry and consumer products in recent years,causing potential harm to the environment.However,currently the impact of 6∶ 2 FTOH and its degradation products on microbial communities in sediment is unclear.The purpose of this study is to explore the impact of the biodegradation of 6∶ 2 FTOH on bacterial community structures in surface sediment based on gene analysis.Surface sediment and river water were collected from Hai river,Tianjin,and a microcosm experiment was performed in the laboratory.The concentration of 6∶ 2 FTOH and its degradation products were analyzed by liquid chromatograph-mass spectrometry/mass spectrometry（LC-MS/MS）.The bacterial community structure was analyzed by denaturing gradient gel electrophoresis and high-throughput sequencing.The results showed that 6∶ 2 FTOH could be degraded by microorganisms（half-life was less than 3 d）,producing transient products such as 6∶ 2 fluorotelomer carboxylic acid（FTCA） and 6∶ 2 fluorotelomer unsaturated carboxylic acid（FTUCA） and stable products such as 5 ∶ 2 fluorotelomer（FT） ketone,5 ∶ 2 fluorotelomer alcohol（sFTOH）,perfluorohexanoic acid（PFHxA）,perfluoro-n-pentanoic acid（PFPe A）,perfluorobutanoic acid（PFBA） and 5∶ 3 polyfluorinated acid.At different stages of 6∶ 2 FTOH degradation,a change of bacteria and the predominant population became somewhat different.Based on the experimental results for 100 d,at the Phylum level,the biodegradation of 6∶ 2 FTOH greatly increases the abundance of Chloroflexi（＋ 24.8%） and decreases the abundance of Proteobacteria（-17.8%） and Firmicutes（-15.9%）.At the Class level,due to the biodegradation of 6∶ 2 FTOH,bacteria with notable increases included Anaerolineae（＋ 19.6%） and δ-Proteobacteria（＋ 4.3%）,while bacteria with notable decreases included ε-Proteobacteria（-20.0%）,Clostridia（-10.1%）,Bacilli（-5.8%） and γ-Proteobacteria�
作者
王丹
侯珍
张琪
周萤
卢晓霞
WANG Dan;HOU Zhen;ZHANG Qi;ZHOU Ying;LU Xiao-xia(Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing 100871, China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2017年第11期4747-4755,共9页
Environmental Science
基金
国家自然科学基金项目(41471391,41030529,40871214)
关键词
6∶2氟调醇
生物降解
细菌群落结构
多样性指数
沉积物
6：2 fluorotelomer alcohol
biodegradation
bacterial community structure
diversity index
sediment
