Plasmidome in mcr-1 harboring carbapenem-resistant enterobacterales isolates from human in Thailand

Abstract

The emergence of the mobile colistin-resistance genes mcr-1 has attracted significant attention worldwide. This study aimed to investigate the genetic features of mcr-1-carrying plasmid among carbapenem-resistant Enterobacterales (CRE) isolates and the potential genetic basis governing transmission. Seventeen mcr-harboring isolates were analyzed based on whole genome sequencing using short-read and long-read platforms. All the mcr-1-carrying isolates could be conjugatively transferred into a recipient Escherichia coli UB1637. Among these 17 isolates, mcr-1 was located on diverse plasmid Inc types, consisting of IncX4 (11/17; 64.7%), IncI2 (4/17; 23.53%), and IncHI/IncN (2/17; 11.76%). Each of these exhibited remarkable similarity in the backbone set that is responsible for plasmid replication, maintenance, and transfer, with differences being in the upstream and downstream regions containing mcr-1. The IncHI/IncN type also carried other resistance genes (blaTEM-1B or blaTEM-135). The mcr-1-harboring IncX4 plasmids were carried in E. coli ST410 (7/11; 63.6%) and ST10 (1/11; 9.1%) and Klebsiella pneumoniae ST15 (1/11; 9.1%), ST336 (1/11; 9.1%), and ST340 (1/11; 9.1%). The IncI2-type plasmid was harbored in E. coli ST3052 (1/4; 25%) and ST1287 (1/4; 25%) and in K. pneumoniae ST336 (2/4; 50%), whereas IncHI/IncN were carried in E. coli ST6721 (1/2; 50%) and new ST (1/2; 50%). The diverse promiscuous plasmids may facilitate the spread of mcr-1 among commensal E. coli or K. pneumoniae strains in patients. These results can provide information for a surveillance system and infection control for dynamic tracing.

Genetic characterization of multidrug-resistant Escherichia coli harboring colistin-resistant gene isolated from food animals in food supply chain

“…To analyze the genetic relationship of the mcr -carrying E . coli isolated in this study, we conducted a phylogenomic analysis using available genomes of mcr -carrying E. coli (n = 12) isolated from patients in Thailand in another study ( Boueroy et al., 2022 ). The phylogenetic tree had two main distinct clades.…”

“…Acquired resistance genes and chromosomal mutation-mediated antimicrobial resistance genes were identified using the ResFinder 4.1 program ( Zankari et al., 2012 ) from CGE and the resistance gene identifier from the Comprehensive Antibiotic Resistance Database ( Alcock et al., 2023 ). A SNP-based phylogenetic tree was constructed to compare twelve E. coli strains isolated from patients in Thailand ( Paveenkittiporn et al., 2021 ; Boueroy et al., 2022 ) ( Supplementary Table 1 ) with the sixteen mcr-1 harboring E. coli strains from food-animal products in this study. The construction of the tree was carried out using REALPHY online tool ( Bertels et al., 2014 ).…”

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

“…Given this evidence, we speculated that ECSJ33 may have originated via the food chain and integrated into wastewater ( 8 , 35 , 36 ). This highlights the importance of surveillance efforts to monitor the emergence and dissemination of mcr-1 among the elderly in LTCFs, as well as the co-existence of ESBL genes such as bla TEM-135 and mcr-1 gene carrying E. coli , which have been reported globally, particularly in animal source E. coli isolates from food-producing animal in Poland located on IncX4 plasmid ( 37 ), from human in Thailand located on IncHI/IncN plasmid ( 38 ), and from human in China located on IncI2 plasmid ( 24 ). Our study identified, for the first time, the co-existence of bla TEM-135 and mcr-1 from a wastewater source isolate in E. coli in Shanghai.…”

Virotyping and genetic antimicrobial susceptibility testing of porcine ETEC/STEC strains and associated plasmid types

“…Dissemination of mcr genes, conferring resistance to colistin, was first detected on IncHI2 plasmid which was also the case in our strains. In addition, the mcr-2.1 gene was identified on a IncX4 plasmid ( Falgenhauer et al, 2016 ; Boueroy et al, 2022 ). This plasmid was first identified in Denmark and is a global concern as elevated numbers of human plasmids were identified to carry colistin resistance genes ( Hasman et al, 2015 ; Elbediwi et al, 2019 ).…”