Cooperation of Adhesin Alleles in Salmonella -Host Tropism

Abstract

Salmonella enterica remains a leading foodborne bacterial pathogen in the United States; infected livestock serve often as the source of contaminated food products. A study estimated that over a billion Salmonella gastroenteritis cases and up to 33 million typhoid cases occur annually worldwide, with 3.5 million deaths. Although many Salmonella strains with a broad host range present preferential associations with certain host species, it is not clear what determines the various levels of host adaptation. Here, causal properties of host associations were determined with allelic variants of three colonization factors of S. enterica serovar Newport, a most frequent zoonotic serovar. This is the first study that related not only individual but also a small group of host-associated gene variants with functional properties that cooperate to determine the level of host-adapted virulence. The detected associations should help to identify sources of Salmonella infections in both humans and animals.