Genome-wide identification of geographical segregated genetic markers in Salmonella enterica serovar Typhimurium variant 4, [5], 12:i:-. Issue 1 (December 2018)

• Record Type: Journal Article
• Authors: Palma, Federica; Manfreda, Gerardo; Silva, Mickael; Parisi, Antonio; Barker, Dillon; Taboada, Eduardo; Pasquali, Frédérique; Rossi, Mirko
• Is Part Of: Scientific reports. Volume 8:Issue 1(2018)
• Page Start: 1
• Page End: 12
• Publication Date: 2018-12
• Subjects: Natural history -- Research -- Periodicals; Biology -- Research -- Periodicals; Physical sciences -- Research -- Periodicals; Earth sciences -- Research -- Periodicals; Environmental sciences -- Research -- Periodicals; 502.85
• DOI: 10.1038/s41598-018-33266-5
• Languages: English
• ISSNs: 2045-2322

Abstract

Abstract Salmonella enterica ser. Typhimurium monophasic variant 4, [5], 12:i:- has been associated with food-borne epidemics worldwide and swine appeared to be the main reservoir in most of the countries of isolation. However, the monomorphic nature of this serovar has, so far, hindered identification of the source due to expansion of clonal lineages in multiple hosts and food producing systems. Since geographically structured genetic signals can shape bacterial populations, identification of biogeographical markers inS . 1, 4, [5], 12:i:- genomes can contribute to improving source attribution. In this study, the phylogeographical structure of 148 geographically and temporally related ItalianS . 1, 4, [5], 12:i:- has been investigated. The Italian isolates belong to a large population of clonalS . Typhimurium/1, 4, [5], 12:i:- isolates collected worldwide in two decades showing up to 2.5% of allele differences. Phylogenetic reconstruction revealed that isolates from the same geographical origin form highly supported monophyletic groups, suggesting discrete geographical segregation. These monophyletic groups are characterized by the gene content of a largesopE -containing prophage. Within this prophage, genome-wide comparison identified several genes overrepresented in strains of Italian origin. This suggests that certain lineages may be characterized by the acquisition of specific accessory genetic markers useful for improving identification of the source in ongoing epidemics.