Evaluation of Antibiotic Resistance of Salmonella Serotypes and Whole-Genome Sequencing of Multiresistant Strains Isolated from Food Products in Russia

Abstract

Food products may be a source of Salmonella, one of the main causal agents of food poisoning, especially after the emergence of strains resistant to antimicrobial preparations. The present work dealt with investigation of the occurrence of resistance to antimicrobial preparations among S. enterica strains isolated from food. The isolates belonged to 11 serovars, among which Infantis (28%), Enteritidis (19%), and Typhimurium (13.4%) predominated. The isolates were most commonly resistant to trimethoprim/sulfamethoxazole (n = 19, 59.38%), cefazolin (n = 15, 46.86%), tetracycline (n = 13, 40.63%), and amikacin (n = 9, 28.13%). Most of the strains (68.75%) exhibited multiple resistance to commonly used antibiotics. High-throughput sequencing was used to analyse three multidrug-resistant strains (resistant to six or more antibiotics). Two of them (SZL 30 and SZL 31) belonged to S. Infantis, while one strain belonged to S. Typhimurium (SZL 38). Analysis of the genomes of the sequenced strains revealed the genes responsible for antibiotic resistance. In the genomes of strains SZL 30 and SZL 31 the genes of antibiotic resistance were shown to be localized mostly in integrons within plasmids, while most of the antibiotic resistance genes of strain SZL 38 were localized in a chromosomal island (17,949 nt). Genomes of the Salmonella strains SZL 30, SZL 31, and SZL 38 were shown to contain full-size pathogenicity islands: SPI-1, SPI-2, SPI-4, SPI-5, SPI-9, SPI-11, SPI-13, SPI-14, and CS54. Moreover, the genome of strain SZL 38 was also found to contain the full-size pathogenicity islands SPI-3, SPI-6, SPI-12, and SPI-16. The emergence of multidrug-resistant strains of various Salmonella serovars indicates that further research on the transmission pathways for these genetic determinants and monitoring of the distribution of these microorganisms are necessary.

Comparison of Reference-Based Assembly and De Novo Assembly for Bacterial Plasmid Reconstruction and AMR Gene Localization in Salmonella enterica Serovar Schwarzengrund Isolates

“…Nevertheless, the presence of three IncFIB plasmids and one IncX1 plasmid found among the isolates that carried several AMR genes was particularly worrisome, as they increase the risk of spreading multiple resistance genes. Although the AMR genes (TEM-1, AAC(3)-IV, APH(4)-Ia, and floR) carried by the IncX1 plasmid in this study were completely different from those reported in previous work (repA, qnrS1, tet(A), cmlA1, sul3, and bla TEM-1B genes) [48][49][50], the current observations could be well-explained by prior research showing that isolates originating from different countries belonging to different lineages may be exposed to different environments and therefore carry different resistance genes [51]. On the other hand, all isolates carried an IncFIB plasmid that could increase colonization in the chicken cecum, which may help to explain its persistence in the food animal population [52].…”

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

“…Salmonellosis is the second most common gastrointestinal infection in humans after campylobacteriosis in the European Union [ 4 ] and is even a leading reported foodborne illness in some parts of the USA [ 5 ]. In the Russian Federation, salmonellosis remains an important cause of foodborne outbreaks, being third in the incidence among infections with a fecal–oral transmission mechanism [ 6 ].…”

Multiple Drug Resistance Salmonella and Antibiotic Residues in Egyptian Animal Products

“…It has been suggested that the increasing incidence of AR of Salmonellosis may result from misusing these antibiotics in veterinary fields (Economou and Gousia, 2015). Rakitin et al (2022) investigated the incidence of antimicrobial resistance among salmonella enterica strains obtained from food; their findings indicated that MDR against routinely used antibiotics as most of the strains (68.75%) exhibited multiple AR against the most commonly used antibiotics. The rise of MDR Salmonella strains is a worldwide public health concern.…”