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Physiological stress drives the emergence of a Salmonella subpopulation through ribosomal RNA regulation

ABSTRACT: Bacteria undergo cycles of growth and starvation, to which they must adapt swiftly. One important strategy for adjusting growth rates relies on ribosomal levels. While high ribosomal levels are required for fast growth, their dynamics during starvation remain unclear. Here, we analyzed ribosomal RNA (rRNA) content of individual Salmonella cells using Fluorescence In-Situ Hybridization (rRNA-FISH), and measured during nutrient limitation a dramatic decrease in rRNA numbers only in a subpopulation, resulting in a bimodal distribution of cells with high and low rRNA content. During nutritional upshifts the two subpopulations were associated with distinct phenotypes. Using a transposon screen coupled with rRNA-FISH, we identified two mutants, DksA and RNase I, acting on rRNA transcription shutdown and degradation, that abolished the formation of the subpopulation with low rRNA content. Our work identifies a bacterial mechanism for regulation of ribosomal bimodality that may be beneficial for population survival during starvation.

ORGANISM(S): Salmonella enterica subsp. enterica serovar Typhimurium str. 14028S

PROVIDER: GSE243242 | GEO | 2025/02/01

REPOSITORIES: GEO

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