Abstract:
Perfluoroalkyl substances (PFASs) and antibiotic resistance genes (ARGs) in drinking water are environmental issues that require special attention. The objective of this study was to know the effects of PFASs on microbial communities and their functional genes from source water to tap water. PFASs were detected by mass-labeled internal standards method, and the microbial communities and functional genes were analyzed by metagenomics. Our results indicated that the concentration of total PFASs in the water ranged from 47.7 to 171.4 ng/L, with perfluorobutanoic acid (PFBA) and perfluorooctanoic acid (PFOA) being the dominant types. The PFASs concentration decreased slowly from source to tap water in some months. PFBA, PFOA, perfluorooctane sulfonic acid (PFOS) and perfluorohexanoic acid (PFHxA) influenced the functional genes related to two-component system, bacterial secretion system and flagellar assembly of Aquabacterium, Methylobacterium, and Curvibacter, which contributed significantly to macB and evgS. Therefore, the bacterial communities enhanced adaptation to fluctuating environments by upregulating some functional genes under the PFASs stress, with concomitant changes in the expression of ARGs. Moreover, PFASs also promoted the expression of functional genes associated with human diseases, such as shigellosis and tuberculosis, which increased the risk of human pathogenicity. The bench scale experiment results also suggested that PFOA and PFOS in drinking water can promote the ARGs proliferation and induce microbial risk. Therefore, it is necessary to take measures to prevent the risks caused by PFASs and ARGs in drinking water.
摘要:
饮用水中的全氟烷基物质(PFAS)和抗生素抗性基因(ARGs)是需要特别注意的环境问题。本研究的目的是了解PFASs对从水源水到自来水的微生物群落及其功能基因的影响。用质量标记内标法检测PFASs,并通过宏基因组学分析了微生物群落和功能基因。我们的结果表明,水中总PFASs的浓度范围为47.7至171.4ng/L,全氟丁酸(PFBA)和全氟辛酸(PFOA)是主要类型。PFASs浓度在几个月内从水源到自来水缓慢下降。PFBA,PFOA,全氟辛烷磺酸(PFOS)和全氟己酸(PFHxA)对双组分系统相关功能基因的影响,细菌分泌系统和细菌鞭毛组装,甲基杆菌,和Curvibacter,对macB和evgS有重要贡献。因此,在PFAS胁迫下,细菌群落通过上调一些功能基因来增强对波动环境的适应性,伴随ARGs表达的变化。此外,PFASs还促进了与人类疾病相关的功能基因的表达,如志贺氏菌病和肺结核,这增加了人类致病性的风险。实验结果还表明,饮用水中的PFOA和PFOS可以促进ARGs的增殖并引起微生物风险。因此,有必要采取措施防止饮用水中PFASs和ARGs引起的风险。