Genetic epidemiology and plasmid-mediated transmission of mcr-1 by Escherichia coli ST155 from wastewater of long-term care facilities

作者：Jun Feng, Miao Pan, Yuan Zhuang, Jiayuan Luo, Yong Chen, Yitong Wu, Jiayi Fei, Yanqi Zhu, Zhen Xu, Zhengan Yuan, Chen Min · 发表于：Microbiology Spectrum · 年份：2024 · DOI：10.1128/spectrum.03707-23 · 被引用次数：8 · 研究领域：Antibiotic Resistance in Bacteria、Pharmaceutical and Antibiotic Environmental Impacts、Enterobacteriaceae and Cronobacter Research

ABSTRACT Long-term care facilities (LTCFs) for older people play an important and unique role in multidrug-resistant organism transmission. Herein, we investigated the genetic characteristics of mobile colistin resistance gene ( mcr-1 )-carrying Escherichia coli strains isolated from wastewater of LTCFs in Shanghai. Antimicrobial susceptibility test was carried out by agar dilution methods. Whole-genome sequencing and plasmid sequencing were conducted, and resistance genes and sequence types of colistin in E. coli isolates were analyzed. Core genome multilocus sequence typing (cgMLST) analysis was performed by the Ridom SeqSphere+ software. Phylogenetic tree through the maximum likelihood method was constructed by MEGA X. Out of 306 isolates, only 1 E. coli named ECSJ33 was found, and the plasmid pECSJ33 from ECSJ33 harbored the mcr-1 gene that was located with 59,080 bp belonging to IncI2 type. The plasmid pECSJ33 was capable of conjugation with an efficiency of 2.9 × 10 −2 . Bioinformatic analysis indicated pECSJ33 shared backbone with the previously reported mcr-1 -harboring pHNGDF93 isolated from fish source. Moreover, the cgMLST analysis revealed that ECSJ33 belongs to different lineages from those reported from previous E. coli strains but shared high similarity to NCTC11129 in cluster 11. The phylogenetic tree revealed MCR-1 of ECSJ33 in this study was mostly of animal food origin and that they were closely related. Our study firstly reports detection of genome sequenc...