DiverseEscherichia colilineages, from domestic animals and humans in a household, carry colistin resistance genemcr-1in Ecuador

Abstract

23The aim of this study was to investigate the presence of Escherichia coli carrying mcr-1 gene 24 in domestic animals close to a child who suffered a peritoneal infection by a mcr-1 positive 25 E. coli. Rectal or cloacal swabs and fecal samples from domestic animals were plated on 26 selective media to isolate colistin-resistant E. coli and isolates were submitted to detection of 27 mcr-1 gene, pulsed field gel electrophoresis (PFGE), multi-locus sequence typing (MLST), 28 replicon typing and S1-PFGE. Four mcr-1 positive E. coli isolates (from chicken, turkey and 29 dog) were recovered. No shared PFGE pattern or MLST sequence type were observed among 30 isolates. A 60Kb IncI1 mcr-1-carrying plasmid was detected in all isolates. Our results 31 suggest that mcr-1 gene was horizontally disseminated amongst different lineages of E. coli 32 from domestic animals in the child's household. 33 Importance 34Horizontally transferable colistin resistance (mcr-1 gene) is thought to have originated in 35 domestic animals and transferred to humans through meat and dairy products. In the present 36 report we show evidence that the mcr-1 gene could be transferred to different E. coli strains 37 colonizing different hosts (humans and pets) in the same household. 38 42 different bacterial genera colonizing different animal species (2, 3).43 3The first report of a colistin resistance (CR) gene carried by plasmids (mcr-1) came from China in 44 2015 (4). This gene codes for a phosphoethanolamine transferase (MCR-1), which modifies the 45 lipid A moiety in the outer membrane of Gram negative bacteria and confers resistance to 46 polymyxins (4, 5). Among Enterobacteriacea different mcr gen groups (1-5) could be transferred by 47 PCR was performed to detect mcr gene (4); amplicons were sequence and aligned using mcr-1 130 (NG_055582.1), mcr-2 (NG_051171.1), mcr-3 ( NG_056184.1), mcr-4( MG822665.1), mcr-5 131 (MG384740.1) accession numbers with Geneius software. Pulsed field gel electrophoresis (PFGE) 132 (25) and multilocus sequence typing (MLST) was performed on seven housekeeping genes to 133 define clonal relatedness (26). Replicon typing was performed using a commercial kit (PBRT KIT, 134 DIATHE, Fano, Italy) (20, 27, 28). -lactamase genes (blaCTX-M-1, blaTEM, blaSHV) were detected 135 using primers previously described (29). Briefly, 12,5mL of GoTaq ® Green Master Mix 136 (Promega, Madison, USA) were mixed with 1L of upstream primer, 10M, 1L of downstream 137 primer, 10 L of DNA template and 9,5 L of Nuclease-free water to complete a 25L of 138 reaction volume. The reaction mix were amplified using 2-minute of initial denaturation at 94°C 139 followed by 40 cycles of DNA denaturation at 94°C (40 sec), annealing at 60°C (40sec) and 140 extension at 72°C (1min). The final elongation step at 72°C for 5 min. Amplicons were detected by 141 electrophoresis in a 2% agarose gel. For complete amplification and sequencing of the detected 142resistance genes, primers and conditions previously described were used (30). 143 S1-PFG...

Whole-Genome Sequencing-Based Characteristics in Extended-Spectrum Beta-Lactamase-Producing Escherichia coli Isolated from Retail Meats in Korea

“…Of these STs, ST93 and ST602 were reported to be infrequent in humans but more frequent in animal samples (specifically chicken) [24,76,77], suggesting that the strains of groups ST93 and ST602 were present in chicken, since farming stages and chicken act as reservoirs for these clonal groups. ST2170 was previously reported in retail chicken meat and turkey in Japan and Ecuador, respectively [68,78].…”

mcr-1-carrying Enterobacteriaceae isolated from companion animals in Brazil

“…It was demonstrated that the bacterial isolate from one of the owners presented the same genetic group as 5 isolates from dogs and cats, highlighting the possible transmission of strains carrying this gene between animals and contacting humans. In another study, carried out in Ecuador by Loayza et al (2018), the presence of E. coli carrying the mcr-1 gene was demonstrated in companion animals sharing the same environment as a child with peritoneal infection by mcr-1positive E. coli, suggesting a clonal dissemination, since the detected mcr-1 gene belonged to the same plasmid in all isolates. In view of the aforementioned, it is observed that the presence of the gene in strains isolated from companion animals can be a natural reservoir, introducing another complex form of dissemination in the community (McEwen & Collignon 2018).…”

Reliable fluorescence technique to detect the antibiotic colistin, a possible environmental threat due to its overuse

“…Escherichia coli ( E. coli ) lineages having colistin-resistant gene mcr-1 were isolated from domestic animals and humans living in the same household in Ecuador . The results suggested that mcr-1 gene is horizontally transferred amongst E. coli lineages in humans from the domestic animal in the household 10 . Recently, colistin resistant mcr-4 and mcr-5 genes were isolated from the upper and lower alimentary tract of poultry chicken and pigs in China 11 .…”