Genomic characterization of Salmonella Cerro ST367, an emerging Salmonella subtype in cattle in the United States

摘要: Within the last decade, Salmonella enterica subsp. serovar Cerro (S. Cerro) has become one of most common serovars isolated from cattle and dairy farm environments in northeastern US. The fact that this is commonly subclinically infected rarely associated with human disease, despite its frequent isolation cattle, led to hypothesis emerging may be characterized by reduced virulence. We applied comparative population genomic approaches (i) characterize evolution recently emerged (ii) gain a better understanding features could explain some unique epidemiological serovar. In addition generating de novo draft genome for strain, we also generated whole sequence data 26 additional S. isolates, including 16 operations New York (NY) state, 2 clinical cases NY 2008, 8 diverse animal sources (7 Washington state 1 Florida). All isolates sequenced study represent type ST367. Population analysis showed form well-supported clade within ST367 (designated here “NY bovine clade”), distinct Florida cases. A molecular clock indicates recent ancestor dates back 1998, supporting emergence clone. Comparative analyses revealed several relevant ST367, responsible virulence Cerro, an insertion creating premature stop codon sopA. addition, patterns gene deletion further support adaptation clone ecological or host related niche. Our results indicate increase prevalence caused highly clonal subpopulation deletions specific niches possibly hosts.