Occurrence and molecular epidemiology of fosA3-bearing Escherichia coli from ducks in Shandong province of China

Abstract

The plasmid-borne fosfomycin resistance gene fosA3 has been identified in Escherichia coli ( E. coli ) from various animals but has rarely been reported in ducks. In this study, we investigated the fosA3 prevalence and molecular characteristics of fosA3 -harboring E. coli strains from ducks in Shandong province of China. In 416 E. coli isolates, 91 (21.88%) were identified as fosA3 -bearing strains, and the fosfomycin-resistant phenotype of 88 of the 91 fosA3 -harboring strains was successfully transferred to the recipient strains. Seven different genetic structures surrounding the fosA3 gene were detected and 2 new contexts were discovered among the fosA3 -carrying E. coli . Twenty fosA3 -harboring isolates and their trans-conjugants were randomly selected for pulsed-field gel electrophoresis ( PFGE ) typing and S1-nuclease PFGE, respectively. The PFGE patterns revealed that the 20 randomly selected fosA3 -bearing isolates were not a result of clonal dissemination. S1-PFGE showed that 15 of the 20 randomly selected trans-conjugants carried a single plasmid, and these 15 plasmids that harbored fosA3 (55–190 kb) were distributed into the following replicon types: IncF (n = 11), IncI1 (n = 1), IncN (n = 1), untypable (n = 1), and W-FIC (n = 1). Additionally, as vectors for fosA3 in E. coli , F-:A1:B6, N/ST1, IncI1/ST2, W-FIC, and one untypable plasmid had never been reported before. These observations highlighted the importance of ducks as a reservoir for multidrug-resistant fosA3 -carrying E. coli .

Spread and Molecular Characteristics of Enterobacteriaceae Carrying fosA -Like Genes from Farms in China

“…However, this study revealed that the fosA -like genes in animal-derived Enterobacteriaceae isolates have a general prevalence, with fosA3 (26%) having the highest detection rate. This rate was higher than the previously reported positivity rate for fosA3 in humans, ducks, and pets ( 7 , 10 , 19 ). In addition, all strains containing fosA -like genes in this study exhibited a high-level resistance to fosfomycin (MIC ≥ 512 μg/mL).…”

High rate of multidrug resistance and integrons in Escherichia coli isolates from diseased ducks in select regions of China

“…Then, ARGs identified in MDR bacterial isolates were tet A (77.1%), sul2 (53.2%), and bla CTX-M (47.3%), which might suggest the widespread usage of tetracycline, sulfonamides, and β-lactams in waterfowl breeding industry. Several studies have reported on the incidence of MDR and ARGs in bacteria, including those by Fashae et al (2021) , Talavera-González et al (2021) , Liu et al (2022a) , and Li et al (2023) . The prevalence of different ARGs in bacteria primarily depends on the frequency of antibiotic use and the level of exposure to various antibiotics.…”

Fosfomycin resistance mechanisms in Enterobacterales: an increasing threat

“…Based on the transposon composition, five major fosA3 environment can be classified in Enterobacterales (named type A-E): A) IS 26-fosA3-orf1-orf2- Δ orf3- IS 26 , B) IS 26-fosA3-orf1- Δ orf2- IS 26 , C) IS 26-fosA3- Δ orf1- IS 26 , D) IS 26 -IS Ecp1 - bla CTX-M-14 -ΔIS 903D-fosA3-orf1- Δ orf2- IS 26 , E) IS 26 -IS Ecp1 - bla CTX-M-65 -ΔIS 903D-fosA3-orf1-orf2- Δ orf3- IS 26 ( Figures 9A–E ). The type A is the predominant type, and it is associated to IncF, IncI1, IncN, IncB/O and several untypable plasmids ( Ho et al., 2013 ; Liu et al., 2022 ). FosA3 can be easily co-harbors on the same plasmid with other ESβLs, as bla CTX-M-3 , bla CTX-M-8 , -14 , -55 , -65 and -123 ( Ho et al., 2013 ; Mazé et al., 2014 ; Xie et al., 2016 ; Yang et al, 2016 ; Dantas Palmeira et al., 2018 ).…”

“…Additionally, the authors identified two novel genetic environments surrounding the fosA3 (IS Ecp1 - bla CTX-M-65 -ΔIS 903D -IS 26 - fosA3 - orf1 - orf2 - Δorf3 -IS 26 and IS 26 -IS Ecp1 - bla CTX-M-3 - orf477 - bla TEM-1 -IS 26 - fosA3 - orf1 - orf2 -Δ orf3 -IS 26 ) ( Jiang et al., 2017 ). In E. coli , genomic studies highlighted the occurrence of FosA3 in ST10 ( Seok et al., 2020 ), ST12 ( Hameed et al., 2022 ), ST38 ( Norizuki et al., 2018 ; Hameed et al., 2022 ), ST 46 ( Hameed et al., 2022 ), ST57 ( Hameed et al., 2022 ), ST69 ( Hameed et al., 2022 ; Liu et al., 2022 ), ST95 ( Hameed et al., 2022 ), ST106 ( Seok et al., 2020 ), ST117 ( Fernandes et al., 2018 ; Zhao et al., 2022 ), ST131 ( Galindo-Méndez et al., 2022 ; Hameed et al., 2022 ), ST1193 ( Hameed et al., 2022 ), ST1196 ( Hameed et al., 2022 ), ST2736 ( Wang et al., 2018 ), ST7584 ( Hameed et al., 2022 ), ST10184 ( Hameed et al., 2022 ), ST11350 ( Ewbank et al., 2022 ), ST648 ( Yang et al, 2016 ), ST156 ( Xie et al., 2016 ). The occurrence of plasmid-mediated fosA -like genes turns out to be worrying in ST131 clone due to its virulence and pathogenic features ( Forde et al., 2019 ; Galindo-Méndez et al., 2022 ; Hameed et al., 2022 ).…”

“…Indeed, ST131 is a globally dominant MDR clone associated with UTI, and it is involved in the global dissemination of ESβLs as CTX-M-15 type ( Forde et al., 2019 ; Jafari et al., 2020 ). However, from 2014 to 2018 Liu and colleagues evaluated the prevalence of mobile fosA3 gene in ducks from 23 Chinese farms and they highlighted the predominance of the ST69 as fosA3 -harboring clones among E. coli strains ( Liu et al., 2022 ). Similarly, Loras et al.…”