Genetic Characterization of mcr-1-Positive Multidrug-Resistant Salmonella enterica Serotype Typhimurium Isolated From Intestinal Infection in Children and Pork Offal in China.
Genetic Characterization of mcr-1-Positive Multidrug-Resistant Salmonella enterica Serotype Typhimurium Isolated From Intestinal Infection in Children and Pork Offal in China.
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中国儿童肠道感染和猪内脏分离的mcr-1阳性多重耐药肠沙门氏菌血清型鼠伤寒的遗传特征
DOI：
10.3389/fmicb.2021.774797
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发表时间：
2021
影响因子：
5.2
通讯作者：
Song H
中科院分区：
文献类型：
--
作者：
Zhang H;Xiang Y;Huang Y;Liang B;Xu X;Xie J;Du X;Yang C;Liu H;Liu H;Wang H;Yang M;Wang L;Hu X;Jin L;Li J;Jiang Y;Qiu S;Song H
随着质粒介导的粘菌素耐药基因mcr-1的迅速出现，沙门氏菌耐药性的增加引起了人们的广泛关注。本文报道了中国地区检出的11株携带mcr-1基因的多重耐药肠系沙门氏菌。它们都表现出对粘菌素的耐药性，此外，从儿童粪便样本中分离出的一株对头孢曲松和阿奇霉素也具有耐药性。我们通过聚合酶链式反应对1454株沙门氏菌进行了mcr-1基因检测，这些沙门氏菌均保存在本实验室。对筛选出的mcr-1阳性菌株进行药敏分析。采用脉冲场凝胶电泳法(PFGE)对鼠伤寒沙门氏菌进行遗传多态性分析。用S1-PFGE和Southern blotting对携带mcr-1基因的重组质粒进行鉴定。用质粒接合试验分析粘菌素耐药性的转移性。对携带mcr-1基因的重组质粒进行测序和生物信息学分析。从中国地区儿童和猪内脏中分离到11株mcr-1耐粘菌素鼠伤寒沙门氏菌(MICS4μg/ml)。均为多重耐药株。PFGE结果显示，从不同样品或地点分离的菌株具有相同的基因型别。S1-PFGE和Southern blotting实验表明，3个大小不同的质粒(33、60和250kb)均携带mcr-1基因。质粒接合实验表明，沙门氏菌是通过水平转移获得携带Mcr-1载体的重组质粒。测序和质粒型分析表明，这些质粒分别为IncX4、IncI2和IncHI2型。其中，IncX4和IncI2具有极其相似的骨架，含有一个抗性基因mcr-1。IncHI2表达载体含有blaCTX-M、oqxB、sul、aph、aadA、blaTm等多个抗性基因。我们从中国分离到11株携带鼠伤寒沙门氏菌的mcr-1菌株，并对其特性进行了描述。我们的研究结果表明，mcr-1基因可以通过三种载体的水平转移在肠道细菌中有效传播。此外，IncHI2还可以介导其他耐药基因的转移。这些结果表明，对携带S鼠伤寒杆菌的mcr-1进行持续监测是预防粘菌素耐药性传播的当务之急。
With the rapid emergence of plasmid-mediated colistin resistance gene mcr-1, the increased resistance of Salmonella has attracted extensive attention. This study reports on 11 multidrug-resistant Salmonella enterica serovar Typhimurium strains harboring mcr-1 in China. They all presented resistance to colistin, and additionally, one that was isolated from a child’s stool sample was also resistant to ceftriaxone and azithromycin. We screened 1454 strains of Salmonella for mcr-1 gene through PCR, and these strains are all preserved in our laboratory. Antimicrobial sensitivity analysis was carried out for the screened mcr-1 positive strains. Genetic polymorphism analysis of S. Typhimurium was performed by using the Pulsed-Field Gel Electrophoresis (PFGE). The plasmids harboring mcr-1 were identified by S1-PFGE and southern blotting. Plasmid conjugation assays were used to analyze the transferability of colistin resistance. The plasmids harboring mcr-1 were characterized by sequencing and bioinformatic analysis. Eleven S. Typhimurium strains harboring mcr-1 with colistin resistance (MICs 4μg/ml) were detected, which were isolated from children and pig offal in China. All of them were multidrug-resistant strains. PFGE results revealed that the strains isolated from different samples or locations have identical genotypes. S1-PFGE and southern blotting experiments showed that three plasmids of different sizes (33, 60, and 250 kb) all carried the mcr-1 gene. The plasmid conjugation assays revealed that Salmonella acquired mcr-1 harboring plasmids by horizontal transfer. Sequencing and plasmid type analysis revealed that these plasmids were types IncX4, IncI2, and IncHI2. Among them, IncX4 and IncI2 plasmids had extremely similar backbones and contained one resistant gene mcr-1. IncHI2 plasmid contained multiple resistant genes including blaCTX–M, oqxB, sul, aph, aadA, and blaTEM. We identified 11 mcr-1 harboring S. Typhimurium strains in China and described their characteristics. Our findings indicate that the mcr-1 gene can effectively spread among intestinal bacteria by horizontal transfer of three types of plasmids. Moreover, the IncHI2 plasmid can also mediate the transfer of other drug resistance genes. These results reveal that constant surveillance of mcr-1 harboring S Typhimurium is imperative to prevent the spread of colistin resistance.
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DOI：
10.1016/j.ijfoodmicro.2012.04.015
发表时间：
2012-06-15
影响因子：
5.4
作者：
Gomes-Neves, Eduarda;Antunes, Patricia;Peixe, Luisa
通讯作者：
Peixe, Luisa
影响因子：
2.2
作者：
Jain, Priyanka;Chowdhury, Goutam;Dutta, Shanta
通讯作者：
Dutta, Shanta
影响因子：
2.8
作者：
Ribot, Efrain M.;Fair, M. A.;Barrett, Timothy J.
通讯作者：
Barrett, Timothy J.
从多重耐药产肠毒素大肠杆菌中鉴定出 IncI2 型质粒携带的新型 mcr-1 变体
影响因子：
5.2
作者：
Liu H;Zhu B;Liang B;Xu X;Qiu S;Jia L;Li P;Yang L;Li Y;Xiang Y;Xie J;Wang L;Yang C;Sun Y;Song H
通讯作者：
Song H
影响因子：
3.9
作者：
Wang Z;Xu H;Tang Y;Li Q;Jiao X
通讯作者：
Jiao X