Selection of orphan Rhs toxin expression in evolved Salmonella enterica serovar Typhimurium.

ABSTRACT: Clonally derived bacterial populations exhibit significant genotypic and phenotypic diversity that contribute to fitness in rapidly changing environments. Here, we show that serial passage of Salmonella enterica serovar Typhimurium LT2 (StLT2) in broth, or within a mouse host, results in selection of an evolved population that inhibits the growth of ancestral cells by direct contact. Cells within each evolved population gain the ability to express and deploy a cryptic "orphan" toxin encoded within the rearrangement hotspot (rhs) locus. The Rhs orphan toxin is encoded by a gene fragment located downstream of the "main" rhs gene in the ancestral strain StLT2. The Rhs orphan coding sequence is linked to an immunity gene, which encodes an immunity protein that specifically blocks Rhs orphan to

SUBMITTER: Koskiniemi S 

PROVIDER: S-EPMC3967940 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature