Correction: Signatures of Adaptation in Human Invasive Salmonella Typhimurium ST313 Populations from Sub-Saharan Africa

Two lineages of Salmonella enterica serovar Typhimurium (S. Typhimurium) of multi-locus sequence type ST313 have been linked with the emergence of invasive Salmonella disease across sub-Saharan Africa. The expansion of these lineages has a temporal association with the HIV pandemic and antibiotic usage. We analysed the whole genome sequence of 129 ST313 isolates representative of the two lineages and found evidence of lineage-specific genome degradation, with some similarities to that observed in S. Typhi. Individual ST313 S. Typhimurium isolates exhibit a distinct metabolic signature and modified enteropathogenesis in both a murine and cattle model of colitis, compared to S. Typhimurium outside of the ST313 lineages. These data define phenotypes that distinguish ST313 isolates from other S. Typhimurium and may represent adaptation to a distinct pathogenesis and lifestyle linked to an-immuno-compromised human population.
Author Summary Salmonella enterica is a diverse species, isolates of which can colonise or infect many different animals, including humans and can cause different disease syndromes. S. enterica can be sub-typed using serology into serovars. Isolates from some serovars, known as generalists, can infect multiple hosts (e.g. S. Typhimurium) and usually cause gastroenteritis. However, other serovars exhibit host adaptation or even restriction. Host-adapted serovars such as S. Dublin show preference for a particular host but can also infect other hosts, while host-restricted serovars are capable of infecting only a single host (e.g. S. Typhi in humans) and frequently cause febrile systemic disease (typhoid). In this study, we use genotypic and phenotypic methods to investigate clinical isolates representative of populations of two recently emerged S. Typhimurium lineages of type ST313 associated with invasive disease in sub-Saharan Africa. Our results identify potential characteristics in these isolates that may be associated with adaptation to invasive disease in humans with a compromised immunity.