Zhang Huichuan, Zhao Dongdong, Shi Qiucheng, Quan Jingjing, Li Xi, Yu Yunsong
1 Department of Infectious Diseases, College of Medicine, Sir Run Run Shaw Hospital, Zhejiang University , Hangzhou, Zhejiang, China .
2 Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province , Hangzhou, Zhejiang, China .
Microb Drug Resist. 2018 Oct;24(8):1117-1120. doi: 10.1089/mdr.2017.0291. Epub 2018 May 16.
The inactivated mgrB gene and the mcr-1 gene are important mechanisms of colistin resistance in Klebsiella pneumoniae and they are threats to the clinical use of colistin. In this study, mcr-1 gene was cloned into K. pneumoniae strains (XH209 and KP10) and their derived strains (XH209 M and KP10 M), which showed high-level resistance to colistin. The acquisition of the mcr-1 gene led to colistin resistance in XH209 and KP10, but the addition of mcr-1 gene did not cause change of colistin minimum inhibitory concentrations in the XH209 M and KP10 M. In addition, the impact of mcr-1 gene on growth rate showed strain specific in K. pneumoniae. In conclusion, the mcr-1 gene does not cause the same level of colistin resistance as the inactivated mgrB gene in K. pneumoniae. The mcr-1 gene has no effect on colisitin resistance when it coexists with inactivated mgrB gene in K. pneumoniae.
失活的mgrB基因和mcr-1基因是肺炎克雷伯菌对黏菌素耐药的重要机制，它们对黏菌素的临床应用构成威胁。在本研究中，mcr-1基因被克隆到肺炎克雷伯菌菌株（XH209和KP10）及其衍生菌株（XH209 M和KP10 M）中，这些菌株对黏菌素表现出高水平耐药。mcr-1基因的获得导致XH209和KP10对黏菌素耐药，但mcr-1基因的添加并未导致XH209 M和KP10 M中黏菌素最低抑菌浓度的改变。此外，mcr-1基因对肺炎克雷伯菌生长速率的影响具有菌株特异性。总之，在肺炎克雷伯菌中，mcr-1基因不会导致与失活的mgrB基因相同水平的黏菌素耐药。当mcr-1基因与失活的mgrB基因在肺炎克雷伯菌中共存时，mcr-1基因对黏菌素耐药没有影响。
