摘要
研究了南京某城市污水处理厂MCR-1基因及其携带菌的污染特征,从MCR-1的分布特征、影响因素及MCR-1携带菌的耐药特征等方面综合评价.结果发现MCR-1随处理流程丰度下降,去除率达83.6%,但其相对丰度在出水中显著升高,剩余污泥中含有高浓度MCR-1,浓度达2.88×1012copies/L.粘菌素耐药菌同样沿处理流程逐渐降低,出水降至53CFU/mL,去除率达99.98%,但在剩余污泥中浓度高达2.04×105CFU/mL.相关性分析发现MCR-1丰度与氨氮含量呈正相关,而相对丰度与COD、总氮和硝酸盐含量呈负相关.耐药特征分析表明曝气池(CAST、MSBR)和曝气生物流化池(ABFT)中MCR-1携带菌可耐受较高浓度粘菌素,且污水处理使MCR-1携带菌对粘菌素的耐受能力提高.表明污水处理流程不但无法完全去除MCR-1及其携带菌,且导致耐药性风险提高.本研究可为评价污水中以MCR-1为代表的超级抗性基因的环境风险提供参考.
The study investigated the pollution characteristics of MCR-1and MCR-1hosting bacteria in a municipal wastewater treatment plant in Nanjing,China.Their distribution and influence factors,as well as antibiotic resistance characteristics,were comprehensively assessed.The results indicated that the MCR-1abundance decreased obviously along with the treatment process,with the reduction efficiency of 83.6%.However,its relative abundance increased significantly in the treated effluent.High amount of MCR-1was detected in biosolids,with concentration of up to 2.88×1012 copies/L.On the other hand,the concentration of colistin resistant bacteria also decreased gradually along with the treatment process.Their concentration decreased to 53 CFU/mL in the final effluent,with the reduction efficiency of 99.98%,but up to 2.04×105 CFU/mL were detected in biosolids.According to the correlation analysis,MCR-1abundance positively correlated with ammonia concentration,while the relative abundance of MCR-1showed negative correlation with COD,TN and NO3--N concentration.The antibiotic resistance characteristics analysis indicated that MCR-1hosting bacteria in the activated sludge system(CAST and MSBR)and aeration biological fluid tank(ABFT)were tolerant to significantly higher colistin concentration relative to other sites.Additionally,the level of MCR-1hosting bacteria tolerant to colistin was enhanced by the treatment process,which implied that the wastewater treatment process could not completely reduce MCR-1 and MCR-1hosting bacteria,and even lead to the increase of their potential risks.The study will provide implications for assessing the environmental risks of MCR-1represented super antibiotic resistant genes.
作者
马奔
黄雅梦
王若楠
王新宇
曹振华
张媛
张青云
徐炳乾
袁青彬
MA Ben;HUANG Ya-meng;WANG Ruo-nan;WANG Xin-yu;CAO Zhen-hua;ZHANG Yuan;ZHANG Qing-yun;XU Bing-qian;YUAN Qing-bin(College of Environmental Science and Engineering,Nanjing Tech University,Nanjing 211816,China)
出处
《中国环境科学》
EI
CAS
CSSCI
CSCD
北大核心
2018年第4期1433-1440,共8页
China Environmental Science
基金
国家自然科学基金(51608260)
污染控制与资源化研究国家重点实验室自主课题(PCRRF16029)
关键词
MCR-1
粘菌素
污染特征
分布
耐药特征
MCR-1
colistin
pollution
distribution
antimicrobial resistance characteristic
作者简介
马奔(1998-),男,山西吕梁人,本科生,研究方向为水环境下抗性细菌及抗性基因的检出、分布和去除技术.;责任作者,助理教授,yuanqb@njtech.edu.cn
