Plasmid Composition, Antimicrobial Resistance and Virulence Genes Profiles of Ciprofloxacin- and Third-Generation Cephalosporin-Resistant Foodborne Salmonella enterica Isolates from Russia

Abstract

Salmonella enterica is an important foodborne pathogen worldwide. Ciprofloxacin and extended-spectrum cephalosporins are the common first-line antimicrobial drugs for the treatment of salmonellosis, antimicrobial resistance genes for which are mostly transferred via plasmids. The goal of this work was to perform genomic analysis of plasmids from foodborne S. enterica isolates obtained in Russia based on whole-genome sequencing. In the current study, 11 multidrug-resistant samples isolated in 2021 from 8 regions of Russia were selected based on their resistance to ciprofloxacin and third-generation cephalosporins (CIP-3rd). Whole-genome short-read sequencing (WGS) was performed for all isolates; the samples belonged to five different sequence types (ST32, ST469, ST11, ST142, and ST548) which had different profiles of antimicrobial resistance (AMR) and virulence genes. We have performed additional long-read sequencing of four representative S. enterica isolates, which showed that they carried pESI-like megaplasmids of 202–280 kb length harboring extended-spectrum β-lactamase genes, fluoroquinolone, tetracycline, and aminoglycosides resistance genes, as well as several virulence determinants. We believe that the WGS data obtained will greatly facilitate further studies of foodborne S. enterica isolates epidemiology in terms of their self-transmissible plasmid composition that mediated antimicrobial resistance and virulence determinants conferring selective advantages of this important bacterial pathogen.

The spread of pESI-mediated extended-spectrum cephalosporin resistance in Salmonella serovars—Infantis, Senftenberg, and Alachua isolated from food animal sources in the United States

“…In this study, we used the unique combination of AMR genes, including blaCTX, to search over a half million Salmonella in NCBI PD for the clusters of environmental strains potentially carrying pESI plasmids. In addition to the two well described Salmonella Infantis clusters ESI-CTX-M-65 [9,12,13,19,20] and ESI-CTX-M-1 [5,9], we found two previously unreported Salmonella Infantis clusters carrying pESI ESI-CTX-M-14-1 and ESI-CTX-M-14-2 and two clusters of other serovars, although the isolates in some clusters had been described previously [11,28]. Among them, Salmonella Alachua strain with pESI plasmid has never been reported before.…”

The spread of pESI-mediated extended-spectrum cephalosporin resistance inSalmonellaserovars - Infantis, Senftenberg, and Alachua isolated from food animal sources in the United States

“…In this study, we used the unique combination of AMR genes, including blaCTX, to search over a half million Salmonella in NCBI PD for the clusters of environmental strains potentially carrying pESI plasmids. In addition to the two well described Salmonella Infantis clusters ESI-CTX-M-65 (9,12,13,19,20) and ESI-CTX-M-1(5, 9), we found two previously unreported Salmonella Infantis clusters carrying pESI ESI-CTX-M-14-1 and ESI-CTX-M-14-2 and two clusters of other serovars, although the isolates in some clusters had been described previously (11,28). Among them, Salmonella Alachua strain with pESI plasmid has never been reported before.…”

Epidemiological, Genetic, and Phenotypic Characteristics of Non-Typhoidal Salmonella in Young Children, as Obtained from a Tertiary Hospital in Guangzhou, China

“…However, due to potential adverse effects, fluoroquinolones and aminoglycosides are not typically used in children [13]. Cephalosporins, especially the third-generation cephalosporins, are usually the drugs of choice for salmonellosis treatment in children [54]. The susceptibility tests showed that the rate of resistance to CRO was 10.4%, which was lower than that found in previous domestic studies conducted in children (24.5%, 37.4%, and 40.1% in Fujian, Zhejiang, and Guangdong Province, respectively) [33,38,45].…”