Detection of the mcr-1 gene in Enteropathogenic Escherichia coli (EPEC) and Shigatoxigenic E. coli (STEC) strains isolated from broilers

Abstract

Enteropathogenic Escherichia coli (EPEC) and Shigatoxigenic E. coli (STEC) strains are among the major pathotypes found in poultry and their products, which are capable of causing human enteric infections. Colistin has been claimed the drug of choice against diseases caused by multidrug-resistant Gram-negative bacteria (MDRGN) in humans. The mcr-1 gene was the first plasmidial gene that has been described to be responsible for colistin resistance and has also been detected in birds and poultry products. Our study aimed to detect the mcr-1 gene in enteropathogenic strains of E. coli in order to evaluate the resistance to colistin in broilers. The material was obtained from 240 cloacal samples and 60 broiler carcasses. The strains were isolated by the conventional bacteriological method and by the virulence genes, which characterize the enteropathogenic strains and resistance, and the samples were detected by polymerase chain reaction (PCR). Of the 213 isolated strains of E. coli, 57 (26.76%) were characterized as atypical EPEC and 35 (16.43%) as STEC. The mcr-1 gene was found in 3.5% (2/57) of the EPEC strains and 5.7% (2/35) of the STEC strains. In this study, it was possible to confirm that the mcr-1 resistance gene is already circulating in the broiler flocks studied and may be associated with the pathogenic strains.

Multidrug‐resistant Escherichia coli from free‐living pigeons (Columba livia): Insights into antibiotic environmental contamination and detection of resistance genes

“…The prevalence of the mcr‐1 gene in Enterobacteriaceae is unknown in several countries (Arcilla et al, 2016). In Brazil, recent studies have provided epidemiological data that contribute to understanding mcr‐1 mediated resistance in E. coli isolated from humans (Rossi et al, 2016), animals, food and environmental sources (Fernandes et al, 2016; Lopes, Costa, et al, 2020). In free‐living pigeons, this is the first Brazilian report of the occurrence of an mcr‐1 gene.…”

mcr-mediated colistin resistance in South America, a One Health approach: a review

“…Of the 213 isolated cloacal samples and broiler carcasses strains of E. coli, 57 (26.76%) were characterized as atypical Enteropathogenic E. coli (EPEC) and 35 (16.43%) as Shigatoxigenic E. coli (STEC). The mcr-1 gene was found in 9 of 213, and 3.5% (2/57) becomes of the EPEC strains, and 5.7% (2/35) becomes of the STEC strains [72].…”

Antimicrobial resistance profiles in Escherichia coli isolated from whole-chicken carcasses from conventional, antibiotic-free, and organic rearing systems

“…Although resistance to tigecycline has been reported in 29.3% of E. coli strains isolated from organic chicken farms (Musa et al, 2021), the authors did not rule out the possibility of an environmental origin for the resistant strains. In contrast, resistance to colistin has been detected in several investigations in the poultry production chain, including in Brazil (Lopes et al, 2020;Lentz et al, 2021), with frequencies ranging from 1.8% (Perrin-Guyomard et al, 2016;Pesciaroli et al, 2020) to as high as 57.94% (Barbieri et al, 2021) and 79.8% (Irrgang et al, 2016). In addition, food animals have been suggested as possible reservoirs and spreaders of genes that confer resistance to this class of antimicrobials (Irrgang et al, 2016;Perrin-Guyomard et al, 2016;Guenther et al, 2017;Monte et al, 2017;Yassin et al, 2017;Bitrus et al, 2018;Zhang et al, 2018).…”