Dataset Information

Global phylogenomics of multidrug-resistant Salmonella enterica serotype Kentucky ST198.

ABSTRACT: Salmonella enterica serotype Kentucky can be a common causative agent of salmonellosis, usually associated with consumption of contaminated poultry. Antimicrobial resistance (AMR) to multiple drugs, including ciprofloxacin, is an emerging problem within this serotype. We used whole-genome sequencing (WGS) to investigate the phylogenetic structure and AMR content of 121 S.enterica serotype Kentucky sequence type 198 isolates from five continents. Population structure was inferred using phylogenomic analysis and whole genomes were compared to investigate changes in gene content, with a focus on acquired AMR genes. Our analysis showed that multidrug-resistant (MDR) S.enterica serotype Kentucky isolates belonged to a single lineage, which we estimate emerged circa 1989 following the acquisition of the AMR-associated Salmonella genomic island (SGI) 1 (variant SGI1-K) conferring resistance to ampicillin, streptomycin, gentamicin, sulfamethoxazole and tetracycline. Phylogeographical analysis indicates this clone emerged in Egypt before disseminating into Northern, Southern and Western Africa, then to the Middle East, Asia and the European Union. The MDR clone has since accumulated various substitution mutations in the quinolone-resistance-determining regions (QRDRs) of DNA gyrase (gyrA) and DNA topoisomerase IV (parC), such that most strains carry three QRDR mutations which together confer resistance to ciprofloxacin. The majority of AMR genes in the S. enterica serotype Kentucky genomes were carried either on plasmids or SGI structures. Remarkably, each genome of the MDR clone carried a different SGI1-K derivative structure; this variation could be attributed to IS26-mediated insertions and deletions, which appear to have hampered previous attempts to trace the clone's evolution using sub-WGS resolution approaches. Several different AMR plasmids were also identified, encoding resistance to chloramphenicol, third-generation cephalosporins, carbapenems and/or azithromycin. These results indicate that most MDR S. enterica serotype Kentucky circulating globally result from the clonal expansion of a single lineage that acquired chromosomal AMR genes 30 years ago, and has continued to diversify and accumulate additional resistances to last-line oral antimicrobials. This article contains data hosted by Microreact.

SUBMITTER: Hawkey J

PROVIDER: S-EPMC6700661 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Global phylogenomics of multidrug-resistant Salmonella enterica serotype Kentucky ST198.

Hawkey Jane J Le Hello Simon S Doublet Benoît B Granier Sophie A SA Hendriksen Rene S RS Fricke W Florian WF Ceyssens Pieter-Jan PJ Gomart Camille C Billman-Jacobe Helen H Holt Kathryn E KE Weill François-Xavier FX

Microbial genomics 20190520 7

Salmonella enterica serotype Kentucky can be a common causative agent of salmonellosis, usually associated with consumption of contaminated poultry. Antimicrobial resistance (AMR) to multiple drugs, including ciprofloxacin, is an emerging problem within this serotype. We used whole-genome sequencing (WGS) to investigate the phylogenetic structure and AMR content of 121 S.enterica serotype Kentucky sequence type 198 isolates from five continents. Population structure was inferred using phylogenom ...[more]

PMID: 31107206

Similar Datasets

Project description:Salmonella enterica serovar Kentucky ST198 is a major health threat due to its resistance to ciprofloxacin and several other drugs, including third-generation cephalosporins. Many drug-resistant genes have been identified in the Salmonella genomic island 1 variant K (SGI1-K). In this study, we investigated the antimicrobial resistance (AMR) profile and genotypic relatedness of two isolates of ciprofloxacin-resistant (CIPR) S. Kentucky ST198 from poultry in Northeastern Thailand. We successfully assembled the complete genomes of both isolates, namely SSSE-01 and SSSE-03, using hybrid de novo assembly of both short- and long-read sequence data. The complete genomes revealed their highly similar genomic structures and a novel variant of SGI1-K underlying multidrug-resistant (MDR) patterns, including the presence of blaTEM-1b, which confers resistance to beta-lactams, including cephalosporins and lnu(F) which confers resistance to lincomycin and other lincosamides. In addition, the chromosomal mutations in the quinolone resistance-determining region (QRDR) were found at positions 83 (Ser83Phe) and 87 (Asp87Asn) of GyrA and at positions 57 (Thr57Ser) and 80 (Ser80Ile) of ParC suggesting high resistance to ciprofloxacin. We also compared SSSE-01 and SSSE-03 with publicly available complete genome data and revealed significant variations in SGI1-K genetic structures and variable relationships to antibiotic resistance. In comparison to the other isolates, SGI1-K of SSSE-01 and SSSE-03 had a relatively large deletion in the backbone, spanning from S011 (traG∆) to S027 (resG), and the inversion of the IS26-S044∆-yidY segment. Their MDR region was characterized by the inversion of a large segment, including the mer operon and the relocation of IntI1 and several resistance genes downstream of the IS26-S044∆-yidY segment. These structural changes were likely mediated by the recombination of IS26. The findings broaden our understanding of the possible evolution pathway of SGI1-K in fostering drug resistance, which may provide opportunities to control these MDR strains.IMPORTANCEThe emergence of ciprofloxacin-resistant (CIPR) Salmonella Kentucky ST198 globally has raised significant concerns. This study focuses on two poultry isolates from Thailand, revealing a distinct Salmonella genomic island 1 variant K (SGI1-K) genetic structure. Remarkably, multiple antibiotic resistance genes (ARGs) were identified within the SGI1-K as well as other locations in the chromosome, but not in plasmids. Comparing the SGI1-K genetic structures among global and even within-country isolates unveiled substantial variations. Intriguingly, certain isolates lacked ARGs within the SGI1-K, while others had ARGs relocated outside. The presence of chromosomal extended-spectrum β-lactamase (ESBL) genes and lincosamide resistance, lnu(F), gene, could potentially inform the choices of the treatment of CIPRS. Kentucky ST198 infections in humans. This study highlights the importance of understanding the diverse genetic structures of SGI1-K and emphasizes the role of animals and humans in the emergence of antimicrobial resistance.

Project description:Salmonella enterica serotype Kentucky is frequently associated with high-level fluoroquinolone resistance and has gained epidemiological importance globally. A retrospective screening was performed to understand the national prevalence of ciprofloxacin-resistant S Kentucky in China. S. enterica strains (n = 15,405) were collected within the frame of two national surveillance networks between 2013 and 2017. Thirty-three S. Kentucky strains were detected in 5 of 10 provinces, and 27 were assigned to sequence type 198 (ST198). The 27 isolates were multidrug resistant, with high-level resistance to ciprofloxacin, and 21 isolates were further resistant to extended-spectrum cephalosporins (ESCs). Phylogenomic analysis classified ST198 isolates into two clades (198.1 and 198.2), and recent occurrences of inter-/intraregion and interhost transmission were identified. Phylogenetic reconstruction with a global collection showed that one subclade of clade 198.2 was clustered with historical strains from Egypt, and the other one was clustered with strains from Southeast Asia. Isolates of clade 198.1 were clustered with strains isolated from North America. The various patterns of mutations detected in quinolone resistance-determining regions of GyrA and ParC are accordant with the phylogenetic structure. These findings indicate that our isolates may have various origins. SGI1 was exclusively detected in isolates of clade 198.2 with a highly mosaic structure, which were mainly identified as SGI1-K derivatives. Plasmid-mediated quinolone resistance genes qnrS1 and aac(6')-Ib-cr were identified in three isolates, and bla CTX-M-9 and bla CTX-M-27 were detected in 20 of 21 ESC-resistant isolates. This is the first report of the genetic and epidemiological characterization for the S Kentucky epidemic clone ST198 in China, warranting the necessity of surveillance for the high-risk clone.IMPORTANCE Ciprofloxacin and extended-spectrum cephalosporins are the choice for treatment of severe nontyphoidal S. enterica infections in adults. S. enterica serotype Kentucky ST198 has gained epidemiological importance globally, because the clone is frequently resistant to both of these high-level-resistance drug groups. The genetic and epidemiological characterization of S. Kentucky has been well studied in Western countries; however, the information is unclear for China. To fill in the gap, we here did a retrospective screening on a large collection in China, and ST198 isolates were systematically analyzed by whole-genome sequencing. Our study revealed that multidrug-resistant ST198 has spread in five provinces, and the occurrences of interregion and cross-host clonal disseminations were detected. Of note, phylogenomic analysis suggests that the Chinese isolates may have emerged with diverse origins, including Egypt, Southeast Asia, and North America. This study warrants the necessity of surveillance for the high-risk clone to prevent its further dissemination in China.

Dataset Information

Global phylogenomics of multidrug-resistant Salmonella enterica serotype Kentucky ST198.

Publications

Global phylogenomics of multidrug-resistant Salmonella enterica serotype Kentucky ST198.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets