Highly Virulent and Multidrug-Resistant Escherichia coli Sequence Type 58 from a Sausage in Germany

Abstract

Studies have previously described the occurrence of multidrug-resistant (MDR) Escherichia coli in human and veterinary medical settings, livestock, and, to a lesser extent, in the environment and food. While they mostly analyzed foodborne E. coli regarding phenotypic and sometimes genotypic antibiotic resistance and basic phylogenetic classification, we have limited understanding of the in vitro and in vivo virulence characteristics and global phylogenetic contexts of these bacteria. Here, we investigated in-depth an E. coli strain (PBIO3502) isolated from a pork sausage in Germany in 2021. Whole-genome sequence analysis revealed sequence type (ST)58, which has an internationally emerging high-risk clonal lineage. In addition to its MDR phenotype that mostly matched the genotype, PBIO3502 demonstrated pronounced virulence features, including in vitro biofilm formation, siderophore secretion, serum resilience, and in vivo mortality in Galleria mellonella larvae. Along with the genomic analysis indicating close phylogenetic relatedness of our strain with publicly available, clinically relevant representatives of the same ST, these results suggest the zoonotic and pathogenic character of PBIO3502 with the potential to cause infection in humans and animals. Additionally, our study highlights the necessity of the One Health approach while integrating human, animal, and environmental health, as well as the role of meat products and food chains in the putative transmission of MDR pathogens.

Multidrug-Resistant High-Risk Escherichia coli and Klebsiella pneumoniae Clonal Lineages Occur in Black-Headed Gulls from Two Conservation Islands in Germany

“…ST131 has not only been reported as the major E. coli clone in the clinical setting [ 32 ] but is often also found in veterinary, food, and environmental settings [ 52 , 53 ]. While previous studies have frequently found MDR ST58 strains in farm animals and, to a lesser extent, in wild birds [ 54 , 55 ] and as contaminants of retail meat [ 21 ], ST38 has been detected in several animal species, including broilers, rats, and black-headed gulls [ 12 , 56 ], with the latter matching our results. ST744 and ST617 have also been previously detected in German birds of prey and in rooks wintering in Europe, fitting into the pattern of the locally settled wild birds [ 16 , 57 ].…”

“…Previous studies suggested that a limited number of clonal lineages, such as E. coli sequence types (ST)131, ST38, ST617, ST648, ST744, and ST58 [ 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ] and K. pneumoniae ST11, ST258, ST290, and ST307 [ 23 , 24 ] drive the global distribution of MDR pathogens. Due to the successful combination of virulence and antibiotic resistance, and the apparent lack of host specificity [ 24 , 25 , 26 ], they have the potential to cause infections in humans and animals.…”

Longitudinal Study on Extended-Spectrum Beta-Lactamase-E. coli in Sentinel Mallard Ducks in an Important Baltic Stop-Over Site for Migratory Ducks in Germany

“…There are currently 32 entries for ST714, 19 of which originate from the environment or wildlife sector. A core single-nucleotide polymorphism analysis [ 77 ] of the available Illumina read data revealed that the next most similar isolate, however, originates from the human sector and, like our ST714 isolates, also carries a CTX-M-32 [ 78 ]. This finding underlines the zoonotic nature of these isolates.…”

Geno- and Phenotypic Characteristics of a Klebsiella pneumoniae ST20 Isolate with Unusual Colony Morphology

“…Other isolates were used as reference and control for the performed assays: a multidrug-resistant K. pneumoniae ST307 isolate from a clonal outbreak in the same university hospital (PBIO1953, [ 6 ]), a hypervirulent K. pneumoniae ST86 isolate (hvKP1, [ 23 , 24 ]), and an Escherichia coli K12 (ST10) (W3110, [ 25 ]), as well as an E. coli ST131 (IMT18399, [ 26 ]). All isolates were stored at −80 °C in lysogeny broth (LB; Carl Roth, Karlsruhe, Germany) containing 20% ( v / v ) glycerol (anhydrous; Merck, Darmstadt, Germany).…”

“…Biofilm formation was tested with a crystal-violet (CV) assay [ 26 ]. From overnight cultures in LB, a 1:100 dilution in M9 medium supplemented with 1 mM magnesium sulfate (Carl Roth, Karlsruhe, Germany) and 0.4% glucose (Carl Roth, Karlsruhe, Germany) was prepared and incubated on a rotary shaker at 130 rpm and 37 °C until 0.5 McFarland standard turbidity was reached.…”