Genomic investigation of antimicrobial resistance determinants and virulence factors in Salmonella enterica serovars isolated from contaminated food and human stool samples in Brazil.
This study investigated the antimicrobial resistance determinants, virulence factors and identified serovars in 37 Salmonella enterica strains isolated from human stool and contaminated foods linked to outbreaks that occurred in Brazil over 7 years using whole genome sequencing (WGS). Phylogenetic analysis of selected serovars (S. Typhimurium, S. Infantis, S. London, and S. Johannesburg) was performed. Ten distinct serovars were identified and, 51% of the tested strains (n = 19) showed disagreement with the previous conventional serotyping. The antimicrobial resistance (AMR) determinants or plasmids varied among the strains. Resistome analysis revealed the presence of resistance genes to aminoglycosides [aac (6')-laa, aph (3″)-lb, aph (6)-ld, aadA1 and aadA2], sulfonamides (sul1), trimethoprin (dfrA8), fosfomycin (fosA7) and tetracyclines (tetA, tetB, tetC), as well as point mutations in parC (T57S) and gyrA (S83F). Plasmidome showed the presence of IncHI2, IncHI2A, IncFIB (S), IncFII (S), IncI1 and p0111 plasmids. Eight Salmonella pathogenicity islands and up to 102 stress and/or virulence genes were identified in the evaluated genomes. Virulence genes of K88 fimbrial adhesin were first reported in S. enterica (S. Pomona, S. Bredeney and S. Mbandaka strains). pilW gene was first identified in S. Pomona. Phylogenetic analysis showed that some serovars circulated in Brazil for decades, primarily within the poultry production chain. Findings highlighted the virulence and AMR determinants in strains that may lead to recurring food outbreaks.
['de Melo|Adma Nadja Ferreira|ANF|', 'Monte|Daniel F M|DFM|', 'de Souza Pedrosa|Geany Targino|GT|', 'Balkey|Maria|M|', 'Jin|Qing|Q|', 'Brown|Eric|E|', 'Allard|Marc|M|', 'de Oliveira|Tereza Cristina Rocha Moreira|TCRM|', 'Cao|Guojie|G|', 'Magnani|Marciane|M|', 'Macarisin|Dumitru|D|']
D018829:Adhesins, Bacterial D000818:Animals D000900:Anti-Bacterial Agents D001938:Brazil D024881:Drug Resistance, Bacterial D005243:Feces D005506:Food Contamination D005516:Food Microbiology D005517:Foodborne Diseases D016680:Genome, Bacterial D044404:Genomic Islands D006801:Humans D010802:Phylogeny D010957:Plasmids D011200:Poultry D011201:Poultry Diseases D019779:Salmonella enterica D012703:Serotyping D014774:Virulence D037521:Virulence Factors D000073336:Whole Genome Sequencing
Whole genome sequence Antibiotic resistance Poultry chain Salmonellosis