Análisis comparativo de secuencias de genoma completo de Salmonella entérica serovar Infantis de origen humano y animal

Abstract

Advances in the development of molecular and bioinformatics tools now allow for a faster and more efficient epidemiological investigation of infectious diseases. Whole genome sequencing represents one of the most revolutionary methodologies in the study of pathogens and is becoming a tool commonly used by several health control agencies (CDC, EFSA), as well as by academia. Salmonella enterica constitutes one of the main pathogens causing diseases around the world, thus, among its different non-typhoidal serovars, Infantis constitutes one of the most relevant from the epidemiological point of view, due to the evolution of virulence mechanisms, dissemination and antimicrobial resistance. Therefore, in the present study, a comparative analysis of whole genome sequences of S. infantis from different origins was performed. Five complete genome sequences of human origin belonging to the ST32 type, the detection of 3 pathogenicity islands, the presence of IncFIB type plasmids, genotypic profiles of antibiotic resistance and a phylogenetic analysis between isolates of Ecuadorian origin and representative isolates from different parts of the world were characterized. The phylogenetic distances evidenced close relationships between Ecuadorian isolates with countries of the South American Pacific profile and the United States, which could be a shared common ancestor. Finally, with respect to resistance genes, Ecuadorian isolates show resistance mechanisms for fosfomycins, aminoglycosides, tetracyclines and the presence of the clinically relevant beta-lactamase blaCTX-M-65.