Insights into the amplification of bacterial resistance to erythromycin in activated sludge
Insights into the amplification of bacterial resistance to erythromycin in activated sludge
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DOI：
10.1016/j.chemosphere.2015.03.085
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发表时间：
2015-10-01
期刊：
影响因子：
8.8
通讯作者：
Yang, Jian
中科院分区：
文献类型：
--
作者：
Guo, Mei-Ting;Yuan, Qing-Bin;Yang, Jian
污水处理厂是抗菌剂耐药性的重要蓄水池。然而，污水处理对抗生素耐药性变化的影响却知之甚少。本研究从细菌水平、群落水平和基因水平考察了实验室规模的活性污泥系统中细菌对红霉素的耐药性变化。基于培养依赖法，研究了全异养细菌在生物处理过程中的抗性变化。采用高通量测序和定量聚合酶链式反应等分子手段，对红霉素耐药菌群和9种典型红霉素耐药基因的变化进行了研究，结果表明，活性污泥处理过程中，异养菌对红霉素浓度(大于32 mg/L)的耐受度显著提高，患病率从9.6%上升到21.8%。高通量测序结果显示，对红霉素耐药的异养菌总数多样性明显增加。在生物反应器的进水和出水中，变形杆菌和拟杆菌是两个主要的类群。然而，通过活性污泥处理，变形杆菌的流行率从76%下降到59%，而总门数从18个增加到29个。经生物处理后，erm(A)、mef(E)和erm(D)基因比例显著增加。结果表明，抗生素耐药基因通过活性污泥中不同混合菌种的转移可能是导致抗生素耐药扩增的原因。废水处理中抗生素耐药性的放大风险需要引起更多的关注。(C)2015爱思唯尔有限公司。保留所有权利。
Wastewater treatment plants are significant reservoirs for antimicrobial resistance. However, little is known about wastewater treatment effects on the variation of antibiotic resistance. The shifts of bacterial resistance to erythromycin, a macrolide widely used in human medicine, on a lab-scale activated sludge system fed with real wastewater was investigated from levels of bacteria, community and genes, in this study. The resistance variation of total heterotrophic bacteria was studied during the biological treatment process, based on culture dependent method. The alterations of bacterial community resistant to erythromycin and nine typical erythromycin resistance genes were explored with molecular approaches, including high-throughput sequencing and quantitative polymerase chain reaction.The results revealed that the total heterotrophs tolerance level to erythromycin concentrations (higher than 32 mg/L) was significantly amplified during the activated sludge treatment, with the prevalence increased from 9.6% to 21.8%. High-throughput sequencing results demonstrated an obvious increase of the total heterotrophic bacterial diversity resistant to erythromycin. Proteobacteria and Bacteroidetes were the two dominant phyla in the influent and effluent of the bioreactor. However, the prevalence of Proteobacteria decreased from 76% to 59% while the total phyla number increased greatly from 18 to 29 through activated sludge treatment. The gene proportions of erm(A), mef(E) and erm(D) were greatly amplified after biological treatment. It is proposed that the transfer of antibiotic resistance genes through the variable mixtures of bacteria in the activated sludge might be the reason for the antibiotic resistance amplification. The amplified risk of antibiotic resistance in wastewater treatment needs to be paid more attention. (C) 2015 Elsevier Ltd. All rights reserved.