Phenotypic and genotypic characterization of mcr-1-positive multidrug-resistant Escherichia coli ST93, ST117, ST156, ST10, and ST744 isolated from poultry in Poland

Abstract

Background A plasmid-mediated mechanism of bacterial resistance to polymyxin is a serious threat to public health worldwide. The present study aimed to determine the occurrence of plasmid-mediated colistin resistance genes and to conduct the molecular characterization of mcr-positive Escherichia coli strains isolated from Polish poultry. Methods In this study, 318 E. coli strains were characterized by the prevalence of mcr1–mcr5 genes, antimicrobial susceptibility testing by minimal inhibitory concentration method, the presence of antimicrobial resistance genes was screened by PCR, and the biofilm formation ability was tested using the crystal violet staining method. Genetic relatedness of mcr-1-positive E. coli strains was evaluated by multilocus sequence typing method. Results Among the 318 E. coli isolates, 17 (5.35%) harbored the mcr-1 gene. High antimicrobial resistance rates were observed for ampicillin (100%), tetracycline (88.24%), and chloramphenicol (82.35%). All mcr-1-positive E. coli strains were multidrug-resistant, and as many as 88.24% of the isolates contained the blaTEM gene, tetracycline (tetA and tetB), and sulfonamide (sul1, sul2, and sul3) resistance genes. Additionally, 41.18% of multidrug-resistant, mcr-1-positive E. coli isolates were moderate biofilm producers, while the rest of the strains showed weak biofilm production. Nine different sequence types were identified, and the dominant ST was ST93 (29.41%), followed by ST117 (17.65%), ST156 (11.76%), ST 8979 (11.76%), ST744 (5.88%), and ST10 (5.88%). Moreover, the new ST was identified in this study. Conclusions Our results showed a low occurrence of mcr-1-positive E. coli strains isolated from Polish poultry; however, all the isolated strains were resistant to multiple antimicrobial agents and were able to form biofilms at low or medium level.

Potential sources and characteristic occurrence of mobile colistin resistance (mcr) gene-harbouring bacteria recovered from the poultry sector: a literature synthesis specific to high-income countries

“…A total of one of the mcr-1-positive isolates had a mutation in the chromosomal pmrB gene, further indicating that chromosomal and plasmid-mediated mechanisms simultaneously mediate COL resistance in E. coli strains of avian origin. There were 29 additional resistance genes (including ESBL, AmpC, and PMQR genes) in the mcr-1harbouring isolates, which were extensively diverse belonging to 50 STs (Zając et al, 2019;Cwiek et al, 2021) (Table 2), including HiR pandemic ExPEC clones ST167, ST38, ST117, ST58, ST69, ST88, ST10 and ST410 (Manges et al, 2019). This diversity proves that various plasmids resulted in a diverse range of clones carrying mcr-1 and genes coding against last-resort antimicrobials in Eastern Europe.…”

“…The poultry industry in Eastern Europe has been reported to be a reservoir for MGHB (Karpíšková et al, 2017;Zając et al, 2019;Gelbíčová et al, 2019;Gelbicova et al, 2020, Cwiek et al, 2021. In Poland, 97 isolates carrying mcr-1.1 on diverse plasmids (IncX4, IncFI, IncHI2, IncQ1, TrfA, IncB/O/K/Z, and many others) were detected among 128 faecal COL-resistant E. coli (62.5%) recovered from poultry birds during 2011-2020 (Zając et al, 2019;Cwiek et al, 2021), suggesting that diverse promiscuous plasmids evolved mcr-1 in Poland since at least in 2011. There was an increase in mcr-1-carrying strains from 1.1% in 2011 to 11.6% in 2016, suggesting possible increasing use of COL in breeder farms in countries where day-old chicks are imported into Poland (Zając et al, 2019).…”

Genome Assessment of Carbapenem- and Colistin-Resistant Escherichia coli from Patients in a Sentinel Hospital in China

“…The novel serotype O128: H4 E. coli harboring astA was identified in the mcr-1 -positive E. coli EC21Z-14 belonging to ST117. The E.coli ST117 was an emerging foodborne zoonotic pathogen that has been isolated from the poultry, meat, human, and sea ecosystem [ 42 , 43 , 44 , 45 ]. A recent study showed that the ST117 strains isolated from different hosts had higher genetic similarity, suggesting that ST117 could transfer among different hosts [ 46 ].…”

Clonal Complexes 23, 10, 131 and 38 as Genetic Markers of the Environmental Spread of Extended-Spectrum β-Lactamase (ESBL)-Producing E. coli

“…This is consistent with our results, since all the ST117 strains associated with the phylogroup F and carrying the bla CTX-M1 , bla CTX-M14 and bla SHV-12 genes have been isolated from chicken samples, in a similar way to that described by Ben Said et al [ 44 ]. ST117 is a potential zoonotic that poses a risk of extra-intestinal infections in humans [ 53 ], therefore surveillance of these strains raises concerns [ 54 ]. However, there is a lack of understanding of virulence traits, antimicrobial resistance patterns, and genomic evolution [ 55 ].…”