摘要
抗生素的滥用导致了耐药菌的大量出现,对环境安全和人体健康造成潜在威胁.为研究污水处理厂进出水中的大肠杆菌对典型抗生素——四环素的耐药性和耐药基因的分布状况,以中国深圳市N污水处理厂和F污水处理厂的进水(NJ和FJ)和二沉池出水(NC和FC)为研究对象,从水样中分别分离培养得到86、88、46和52株大肠杆菌,比较菌株在有无添加10 mg/L四环素盐酸盐溶液的培养基中12 h的生长曲线,得到不同菌株对四环素的表观耐药性.结果表明,从污水处理厂进水样品NJ和FJ分离到的大肠杆菌对四环素耐药性检出率分别为36%和23%,出水样品NC和FC中的检出率分别为4%和8%,说明污水处理工艺对降低四环素耐药菌丰度有显著效果.采用聚合酶链式反应(polymerase chain reaction,PCR)和宏基因组学测序方法对部分敏感菌和耐药菌的四环素耐药基因进行检测,结果显示,四环素耐药菌中普遍携带tet(A)、tet(B)、tet(C)、tet(D)、tet(L)和tet(M)等四环素耐药基因,卡方检验(χ2检验)结果表明,四环素耐药基因与其耐药性密切相关.然而,在四环素敏感菌中也检测到四环素耐药基因tet(A),表明抗生素耐药性的表观型和基因型也可能存在不一致现象.该研究为进一步探究耐药菌的耐药机制和挖掘新型的耐药基因提供了实验基础.
The abuse of antibiotics has led to the emergence of antibiotic resistant bacteria,causing potential threats to environmental safety and human health.In order to study the tetracycline resistance and resistance genes of E.coli in sewage treatment plants(STPs),influent samples(NJ,FJ)and effluent samples(NC,FC)from secondary sedimentation tanks from N and F STPs in Shenzhen were collected.86,88,46 and 52 strains of E.coli were isolated from NJ,FJ,NC and FC,respectively.By comparing the growth curves of strains in medium with or without 10 mg/L tetracycline hydrochloride for 12 hours,the apparent resistance of difference strains to tetracycline was obtained.The results showed that the detection rates of tetracycline resistance in E.coli isolated from influent samples NJ and FJ were 36%and 23%,and those from effluent samples NC and FC were 4%and 8%,respectively.It indicated the wastewater treatment process had a significant effect on reducing the abundance of tetracycline resistant bacteria.Polymerase chain reaction(PCR)and metagenomic sequencing analysis showed that tetracycline resistance genes of tet(A),tet(B),tet(C),tet(D),tet(L),and tet(M)were commonly present in tetracycline resistant strains,the Chi-square test(χ2 test)demonstrated that the tetracycline resistance had closely related to resistance genes.However,tet(A)was identified in some sensitive strains,indicating there may be inconsistencies in the phenotype and genotype of antibiotic resistance.The results provide experimental basis for further study of the resistance mechanism of antibiotic resistant bacteria and exploration of novel antibiotic resistance genes.
作者
毛艳萍
田里
陈胜
张雅怡
王越兴
MAO Yanping;TIAN Li;CHEN Sheng;ZHANG Yayi;WANG Yuexing(College of Chemistry and Environmental Engineering,Shenzhen University,Shenzhen 518060,Guangdong Province,P.R.China;Shenzhen Water(Group)Co.Ltd.,Shenzhen 518000,Guangdong Province,P.R.China)
出处
《深圳大学学报（理工版）》
EI
CAS
CSCD
北大核心
2019年第6期642-648,共7页
Journal of Shenzhen University(Science and Engineering)
基金
国家自然科学基金资助项目(51608329)
广东省自然科学基金资助项目(2017A030313315)
深圳市科技计划资助项目(JCYJ20160520165135743,JCYJ20170412171918012)
深圳城市污水处理与再生利用工程实验室资助项目
深圳市环保产业发展专项基金资助项目~~
关键词
应用与环境微生物学
污水处理厂
大肠杆菌
四环素抗性
耐药基因
宏基因组测序
applied and environmental microbiology
sewage treatment plant
E.coli
tetracycline resistance
antibiotic resistance genes
metagenomic sequencing
