State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
Chemosphere. 2020 Sep;255:127032. doi: 10.1016/j.chemosphere.2020.127032. Epub 2020 May 10.
Antibiotics can affect microbial community structure and promote antibiotic resistance. However, the course of microbial community recovery in wastewater treatment systems after antibiotic disturbance remains unclear. Herein, multiple molecular biology tools, including 16S amplicon sequencing, GeoChip 5.0, quantitative polymerase chain reaction (qPCR), and metagenomic sequencing, were used to investigate the year-long (352 d) recovery of the microbial community functional structure in an aerobic biofilm reactor. Nitrification was completely inhibited under 50 mg/L of streptomycin spiking (STM_50) due to the significant reduction of ammonia-oxidizing bacteria, but recovered to original pre-disturbance levels after streptomycin removal, indicating the high resilience of ammonia-oxidizing bacteria. Bacterial community richness and diversity decreased significantly under STM_50 (p < 0.05), but recovered to levels similar to those observed before disturbance after 352 d. In contrast, bacterial composition did not recover to the original structure. The carbon degradation and nitrogen cycling functional community significantly changed after recovery compared to that observed pre-disturbance (p < 0.05), thus indicating functional redundancy. Additionally, levels of aminoglycoside and total antibiotic resistance genes under STM_50 (relative abundance, 0.33 and 0.80, respectively) and after one year of recovery (0.12 and 0.29, respectively) were higher than the levels detected pre-disturbance (0.04 and 0.24, respectively). This study provides an overall depiction of the recovery of the microbial community functional structure after antibiotic exposure. Our findings give notice that recovery caused by antibiotic disturbance in the water environment should be taken more seriously, and that engineering control strategies should be implemented to prevent the antibiotic pollution of wastewater.
抗生素会影响微生物群落结构并促进抗生素耐药性的产生。然而，抗生素干扰后污水处理系统中微生物群落恢复的过程尚不清楚。在此，采用了包括 16S 扩增子测序、GeoChip 5.0、定量聚合酶链反应（qPCR）和宏基因组测序在内的多种分子生物学工具，来研究好氧生物膜反应器中微生物群落功能结构长达一年（352d）的恢复过程。由于氨氧化菌数量的显著减少，在 50mg/L 链霉素（STM_50）冲击下硝化作用完全受到抑制，但在链霉素去除后恢复到原始的未受干扰水平，表明氨氧化菌具有很强的恢复能力。在 STM_50 作用下，细菌群落丰富度和多样性显著降低（p<0.05），但在 352d 后恢复到干扰前的水平。相比之下，细菌组成并没有恢复到原始结构。与干扰前相比，恢复后碳降解和氮循环功能群落发生了显著变化（p<0.05），这表明存在功能冗余。此外，STM_50 下（相对丰度分别为 0.33 和 0.80）和一年恢复后（0.12 和 0.29）的氨基糖苷类和总抗生素抗性基因水平高于干扰前（分别为 0.04 和 0.24）。本研究全面描述了抗生素暴露后微生物群落功能结构的恢复。研究结果表明，应该更加重视水环境中抗生素干扰的恢复，应采取工程控制策略来防止废水的抗生素污染。
