High Prevalence of Plasmid-Mediated Quinolone Resistance among ESBL/AmpC-Producing Enterobacterales from Free-Living Birds in Poland
In this study, we investigated the occurrence of plasmid-mediated quinolone resistance (PMQR) in extended-spectrum β-lactamase- (ESBL) and/or AmpC-type β-lactamase-producing <i>Enterobacterales</i> isolates from free-living birds in Poland. The prevalence of the <i>qnrB19</i>...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-08-01
|
| Series: | International Journal of Molecular Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1422-0067/24/16/12804 |
| Summary: | In this study, we investigated the occurrence of plasmid-mediated quinolone resistance (PMQR) in extended-spectrum β-lactamase- (ESBL) and/or AmpC-type β-lactamase-producing <i>Enterobacterales</i> isolates from free-living birds in Poland. The prevalence of the <i>qnrB19</i> gene was 63%, and the distribution of isolates in terms of bacterial species was as follows: 67% (22/33) corresponded to <i>Escherichia coli</i>, 83% (5/6) to <i>Rahnella aquatilis</i>, 44% (4/9) to <i>Enterobacter cloacae</i> and 33% (1/3) to <i>Klebsiella pneumoniae</i>. The <i>qnrB19</i> gene was also found in a single isolate of <i>Citrobacter freundii</i>. The molecular characteristics of <i>qnrB19</i>-positive isolates pointed to extended-spectrum beta lactamase CTX-M as the most prevalent one (89%) followed by TEM (47%), AmpC (37%) and SHV (16%). This study demonstrates the widespread occurrence of PMQR-positive and ESBL/AmpC-producing <i>Enterobacterales</i> isolates in fecal samples from wild birds. In this work, plasmid pAM1 isolated from <i>Escherichia coli</i> strain SN25556 was completely sequenced. This plasmid is 3191 nucleotides long and carries the <i>qnrB19</i> gene, which mediates decreased susceptibility to quinolones. It shares extensive homology with other previously described small <i>qnrB19</i>-harboring plasmids. The nucleotide sequence of pAM1 showed a variable region flanked by an oriT locus and a Xer recombination site. The presence of a putative recombination site was detected, suggesting that interplasmid recombination events might have played a role in the development of pAM1. Our results highlight the broad geographical spread of ColE-type Qnr resistance plasmids in clinical and environmental isolates of <i>Enterobacterales</i>. As expected from the results of phenotypic susceptibility testing, no resistance genes other than <i>qnrB19</i> were identified. |
|---|---|
| ISSN: | 1661-6596 1422-0067 |