大肠埃希菌临床株QD24对黏菌素和碳青霉烯类耐药的机制  

Carbapenem and colistin resistance mechanisms of a elinical Escherichia coli QD24 strain recowered from China

作　　者：王晓慧[1,2,3] 贾楠 王笑[1,2] 姜美妍 朱元祺 WANG Xiaohui;JIA Nan;WANG Xiao(The Affiliated Hospital of Qingdao University,Qingdao 266003,China)

机构地区：[1]青岛大学附属医院,山东青岛266003 [2]青岛大学医学部,山东青岛266071 [3]淄博市张店区人民医院,山东淄博266034

出　　处：《中国实验诊断学》2023年第5期549-553,共5页Chinese Journal of Laboratory Diagnosis

基　　金：青大附院“临床医学+X”科研项目(2019-3399)。

摘　　要：目的探讨大肠埃希菌临床株QD24对黏菌素和碳青霉烯类耐药的机制。方法通过二代Illumina和三代Nanopore测序技术平台获得大肠埃希菌QD24株的染色体和质粒序列,然后对其进行在线软件分析。液相接合试验、S1核酸酶切脉冲场凝胶电泳(S1-PFGE)和脉冲场凝胶电泳(PFGE)检测菌株携带的质粒。结果测序分析显示大肠埃希菌QD24属于ST69型,携带了黏菌素耐药基因mcr-1.1和碳青霉烯类耐药基因blaNDM-13,且这两个基因分别位于IncHI2型质粒pQD24-1和IncB/O/K/Z型质粒pQD24-3上。液相接合显示大肠埃希菌QD24能将blaNDM-13基因传递到大肠埃希菌J53Azi^(R)。结论大肠埃希菌QD24对黏菌素和碳青霉烯类耐药是因为携带了mcr-1.1和blaNDM-13耐药基因。经检索,同时携带mcr-1.1和blaNDM-13耐药基因ST69型大肠埃希菌为国内外首次报道。Objective To investigate the mechanisms of a clinical Escherichia coli QD24 strain resistant to colistin and carbapenems.Methods The chromosome and plasmid sequences of the Escherichia coli QD24 strain were obtained by second-generation Illumina and third-generation Nanopore sequencing technology platforms,and then analyzed by online software.The plasmids carried by the strain were detected by liquid phase conjugation test,Sl nuclease digestion pulsed field gel electrophoresis(S1-PFGE)and pulsed field gel electrophoresis(PFGE).Results Sequencing analysis showed that Escherichia coli QD24 strain belonged to ST69 and carried colistin resistance gene mcr-1.1 on IncHI2 plasmid pQD24-1 and carbapenem resistance gene blaNDM-13 on IncB/O/K/Z plasmid pQD24-3,respectively.Liquid phase conjugations showed that the Escherichia coli QD24 strain could transfer blaNDM-13 gene on plasmid pQD24-3 to Escherichia coli J53Azi^(R).Conclusion This study indicated that the clinical Escherichia coli QD24 strain was resistant to colistin and carbapenems is because it carried mcr-1.1 and blaNDM-13 genes.To the best of our knowledge,coharboring mcr-1.1 and blaNDM-13 ST69 Escherichia coli strains is firstly reported in the world.

关 键 词：大肠埃希菌 碳青霉烯酶 mcr-1.1 blaNDM-13 黏菌素 

分 类 号：R446.5[医药卫生—诊断学]